Search

Knowing tractor drawbar pull is crucial to ensure the tractor can handle the required workload efficiently and safely, preventing soil damage and optimising field productivity. The present study proposes a novel approach for tractor drawbar pull prediction by utilising the tractor's geometric parameters and forward speed to develop a cloud-infused, server-less, machine learning-based real-time generalised tractor drawbar pull prediction model for any tractor between the 6-58 kW power range. The drawbar pull prediction models from ANN and six ML algorithms were developed, and the data analysis with hyperparameter tuning concluded that the Extreme Gradient Boosting (XGB) ML model outperformed the other ML models. A reasonable accuracy with R2 = 0.93 and MAPE = 6.77% was achieved using the XGB ML model for a separate validation dataset, which was not used for training. Furthermore, a cloud-based serverless Android App integrated with the XGB ML-based drawbar pull prediction model was developed for real-time tractor drawbar pull prediction and monitoring during tillage operations. The field validation demonstrated the XGB ML model's generalisation ability and effectiveness, with R2 = 0.90 and maximum MAPE of 9.86%. It can be used to simulate and optimize tractor performance, guiding manufacturers in selecting geometric parameters for tractor design.

Abstract To date, degraded mangrove ecosystem restoration accomplished worldwide primarily aligns towards rehabilitation with monotypic plantations, while ecological restoration principles are rarely followed in these interventions. However, researchers admit that most of these initiatives' success rate is not appreciable often. An integrative framework of ecological restoration for degraded mangroves where site-specific observations could be scientifically rationalized, with co-located reference pristine mangroves as the target ecosystem to achieve is currently distinctively lacking. Through this experimental scale study, we studied the suitability of site-specific strategies to ecologically restore degraded mangrove patches vis-à-vis the conventional mono-species plantations in a highly vulnerable mangrove ecosystem in Indian Sundarbans. This comprehensive restoration framework was trialed in small discrete degraded mangrove patches spanning ~ 65 ha. Site-specific key restoration components applied are statistically validated through RDA analyses and Bayesian t-tests. 25 quantifiable metrics evaluate the restoration success of a ~ 3 ha degraded mangrove patch with Ridgeline distribution, Kolmogorov–Smirnov (K-S) tests, and Mahalanobis Distance (D2) measure to prove the site’s near-equivalence to pristine reference in multiple ecosystem attributes. This restoration intervention irrevocably establishes the greater potential of this framework in the recovery of ecosystem functions and self-sustenance compared to that of predominant monoculture practices for vulnerable mangroves.

IntroductionBiological nitrogen fixation (BNF), an unparalleled metabolic novelty among living microorganisms on earth, globally contributes ~88-101 Tg N year−1 to natural ecosystems, ~56% sourced from symbiotic BNF while ~22-45% derived from free-living nitrogen fixers (FLNF). The success of symbiotic BNF is largely dependent on its interaction with host-plant, however ubiquitous environmental heterotrophic FLNFs face many limitations in their immediate ecological niches to sustain unhindered BNF. The autotrophic FLNFs like cyanobacteria and oceanic heterotrophic diazotrophs have been well studied about their contrivances acclimated/adapted by these organisms to outwit the environmental constraints for functional diazotrophy. However, FLNF heterotrophs face more adversity in executing BNF under stressful estuarine/marine/aquatic habitats.MethodsIn this study a large-scale cultivation-dependent investigation was accomplished with 190 NCBI accessioned and 45 non-accessioned heterotrophic FLNF cultivable bacterial isolates (total 235) from halophilic estuarine intertidal mangrove niches of Indian Sundarbans, a Ramsar site and UNESCO proclaimed World Heritage Site. Assuming ~1% culturability of the microbial community, the respective niches were also studied for representing actual bacterial diversity via cultivation-independent next-generation sequencing of V3-V4 rRNA regions.ResultsBoth the studies revealed a higher abundance of culturable Gammaproteobacteria followed by Firmicutes, the majority of 235 FLNFs studied belonging to these two classes. The FLNFs displayed comparable selection potential in media for free nitrogen fixers and iron-oxidizing bacteria, linking diazotrophy with iron oxidation, siderophore production, phosphorus solubilization, phosphorus uptake and accumulation as well as denitrification.DiscussionThis observation validated the hypothesis that under extreme estuarine mangrove niches, diazotrophs are naturally selected as a specialized multidimensional entity, to expedite BNF and survive. Earlier metagenome data from mangrove niches demonstrated a microbial metabolic coupling among C, N, P, S, and Fe cycling in mangrove sediments, as an adaptive trait, evident with the co-abundant respective functional genes, which corroborates our findings in cultivation mode for multiple interrelated metabolic potential facilitating BNF in a challenging intertidal mangrove environment.

The global environment is experiencing increasingly rapid pollution due to the presence of harmful products generated by human activities, the emissions from vehicular traffic, and the release of carbon dioxide from industrial sources. To save this beautiful earth as well as human beings, it is necessary to reduce pollution by producing eco-friendly products and reducing reckless carbon emissions from industry. Furthermore, advertising serves as a very efficacious strategy for promoting sustainable green products and encouraging customer engagement. In response to the current circumstances, a supply chain model including a manufacturer, a retailer, and customers is devised, incorporating investments in green practices and advertising. This study examines the relationship between client demand and three key factors: marketing effort, the product's green level, and the selling price. In addition, a sharing contract policy between the manufacturer and the retailer on green investment costs is applied in this model. The main focus of this study is to find the optimal values of advertisement effort, the product's green level, the manufacturer's wholesale price, the retailer's selling price and the sharing percentage of green investment that maximize the profits of the retailer and manufacturer, as well as the integrated supply chain system of the proposed model. In order to demonstrate the practical significance of the concept, a numerical example is solved and then a comparative analysis is conducted. Moreover, sensitivity studies are performed to assess the impact of different model parameters on decision factors and profitability. In conclusion, this study provides management insights and offers some closing observations, along with suggestions for future research directions. The findings indicate that the implementation of a sharing contract policy yields more earnings to the participants in the supply chain compared to a decentralized situation. The centralized strategy in supply chain management (SCM) results in higher joint earnings for the manufacturer and the retailer compared to the decentralized and sharing contract policies.

Bibenzyl derivatives comprising two benzene rings are secondary plant metabolites with significant therapeutic value. To date, bibenzyl derivatives in the Plant kingdom have been primarily identified in bryophytes, orchids, and Cannabis sativa. The metabolic cost investment by plant species for the synthesis of these bioactive secondary metabolites is rationalized as a mechanism of plant defense in response to oxidative stress induced by biotic/abiotic factors. Bibenzyl derivatives are synthesized from core phenylpropanoid biosynthetic pathway offshoots in plant species. Mangrove and mangrove associate species thrive under extreme ecological niches such as a hypersaline intertidal environment through unique adaptive and acclimative characteristics, primarily involving osmotic adjustments followed by oxidative stress abatement. Several primary/secondary bioactive metabolites in mangrove species have been identified as components of salinity stress adaptation/acclimation/mitigation; however, the existence of a bibenzyl scaffold in mangrove species functioning in this context remains unknown. We here report the confirmed detection of a core bibenzyl scaffold from extensive gas chromatography-mass spectrometry and gas chromatography-flame ionization detection analyses of 28 mangrove and mangrove associate species from the Indian Sundarbans. We speculate that the common presence of this bibenzyl core molecule in 28 mangrove and associate species may be related to its synthesis via branches of the phenylpropanoid biosynthetic pathway induced under high salinity, which functions to detoxify reactive oxygen species as a protection for the maintenance of plant metabolic processes. This finding reveals a new eco-physiological functional role of bibenzyls in unique mangrove ecosystem.

Abstract In this work, we have extended the analysis on the generalized Chaplygin gas (GCG) model as the unification of dark energy and dark matter. Specifically, we have shown that the model of our consideration known as the new generalized Chaplygin gas (NGCG) model, admits a scalar field description, which means that there exist a minimally coupled scalar field for a given scalar field potential where the equation of state is that of the NGCG. With the use of the later property we can construct the slow-roll parameters and derive the corresponding values for the spectral indices for the tensor to scalar perturbation and for the density perturbations. We have also studied the growth rate of matter perturbations in the NGCG scenario. Finally, we have studied the viability of the generalized second law of thermodynamics by assuming that the dynamical apparent horizon in a NGCG universe is endowed with Hawking temperature and Bekenstein entropy.

Temperature difference induced H2O2 generation by thermoelectric materials is an attractive strategy for environmental remediation purposes. Here the authors demonstrate Bi2Te3 nanoplates based antibacterial filter as an effective candidate for indoor disinfection applications.

Abstract The paper deals with collapse dynamics of a spherically symmetric massive star in the framework of non-equilibrium thermodynamic prescription through particle creation mechanism. The matter content in the star is in the form of perfect fluid with barotropic equation of state, and the dissipative phenomena due to non-equilibrium thermodynamics is in the form of bulk viscosity. For simplicity, the thermodynamic system is chosen to be adiabatic so that the effective bulk viscous pressure is linearly related to the particle creation rate. As a result, the evolution of the collapsing star also depends on the particle creation rate. By proper choice of creation rate as a function of the Hubble parameter, it is found that the end state of the collapse may be either a black hole (BH) or a naked singularity (NS).

Abstract A rigorous thermodynamic analysis has been done as regards the apparent horizon of a spatially flat Friedmann–Lemaitre–Robertson–Walker universe for the gravitationally induced particle creation scenario with constant specific entropy and an arbitrary particle creation rate $$\Gamma $$ Γ . Assuming a perfect fluid equation of state $$p=(\gamma -1)\rho $$ p=(γ-1)ρ with $$\frac{2}{3} \le \gamma \le 2$$ 23≤γ≤2 , the first law, the generalized second law (GSL), and thermodynamic equilibrium have been studied, and an expression for the total entropy (i.e., horizon entropy plus fluid entropy) has been obtained which does not contain $$\Gamma $$ Γ explicitly. Moreover, a lower bound for the fluid temperature $$T_f$$ Tf has also been found which is given by $$T_f \ge 8\left( \frac{\frac{3\gamma }{2}-1}{\frac{2}{\gamma }-1}\right) H^2$$ Tf≥83γ2-12γ-1H2 . It has been shown that the GSL is satisfied for $$\frac{\Gamma }{3H} \le 1$$ Γ3H≤1 . Further, when $$\Gamma $$ Γ is constant, thermodynamic equilibrium is always possible for $$\frac{1}{2}

The tunnelling mechanism is today considered a popular and widely used method in describing Hawking radiation. However, in relation to black hole (BH) emission, this mechanism is mostly used to obtain the Hawking temperature by comparing the probability of emission of an outgoing particle with the Boltzmann factor. On the other hand, Banerjee and Majhi reformulated the tunnelling framework deriving a black body spectrum through the density matrix for the outgoing modes for both the Bose-Einstein distribution and the Fermi-Dirac distribution. In contrast, Parikh and Wilczek introduced a correction term performing an exact calculation of the action for a tunnelling spherically symmetric particle and, as a result, the probability of emission of an outgoing particle corresponds to a non-strictly thermal radiation spectrum. Recently, one of us (C. Corda) introduced a BH effective state and was able to obtain a non-strictly black body spectrum from the tunnelling mechanism corresponding to the probability of emission of an outgoing particle found by Parikh and Wilczek. The present work introduces the quantum corrected effective temperature and the corresponding quantum corrected effective metric is written using Hawking’s periodicity arguments. Thus, we obtain further corrections to the non-strictly thermal BH radiation spectrum as the final distributions take into account both the BH dynamical geometry during the emission of the particle and the quantum corrections to the semiclassical Hawking temperature.

In the present work we discuss a third alternative to explain the latest observational data concerning the accelerating Universe and its different stages. The particle creation mechanism in the framework of non-equilibrium thermodynamics is considered as a basic cosmic mechanism acting on the flat FRW geometry. By assuming that the gravitationally induced particle production occurs under “adiabatic” conditions, the deceleration parameter is expressed in terms of the particle creation rate which is chosen as a truncated power series of the Hubble parameter. The model shows the evolution of the Universe starting from inflation to the present late time acceleration and it also predicts future decelerating stage. Keywords: Particle creation, Isentropic process, Future deceleration

We would like to rectify an error regarding the validity of the first law of thermodynamics (FLT) on the apparent horizon of a spatially flat Friedmann–Lemaitre–Robertson–Walker (FLRW) universe for the gravitationally induced particle creation scenario with constant specific entropy and an arbitrary particle creation rate (see Sect. 3.1 of original article)

A study of Universal thermodynamics is done in the framework of RSII brane model and DGP brane scenario. The Universe is chosen as FRW model bounded by apparent or event horizon. Assuming extended Hawking temperature on the horizon, the unified first law is examined for perfect fluid (with constant equation of state) and Modified Chaplygin Gas model. As a result there is a modification of Bekenstein entropy on the horizons. Further the validity of the generalized second law of thermodynamics and thermodynamical equilibrium are also investigated.

The present work deals with irreversible universal thermodynamics. The homogenous and isotropic flat model of the universe is chosen as open thermodynamical system and nonequilibrium thermodynamics comes into picture. For simplicity, entropy flow is considered only due to heat conduction. Further, due to Maxwell-Cattaneo modified Fourier law for nonequilibrium phenomenon, the temperature satisfies damped wave equation instead of heat conduction equation. Validity of generalized second law of thermodynamics (GSLT) has been investigated for universe bounded by apparent or event horizon with cosmic substratum as perfect fluid with constant or variable equation of state or interacting dark species. Finally, we have used three Planck data sets to constrain the thermal conductivity λ and the coupling parameter b2. These constraints must be satisfied in order for GSLT to hold for universe bounded by apparent or event horizons.

The paper deals with Hawking radiation from both a general static black hole and a nonstatic spherically symmetric black hole. In case of static black hole, tunnelling of nonzero mass particles is considered and due to complicated calculations, quantum corrections are calculated only up to the first order. The results are compared with those for massless particles near the horizon. On the other hand, for dynamical black hole, quantum corrections are incorporated using the Hamilton-Jacobi method beyond semiclassical approximation. It is found that different order correction terms satisfy identical differential equation and are solved by a typical technique. Finally, using the law of black hole mechanics, a general modified form of the black hole entropy is obtained considering modified Hawking temperature.

The present work deals with the semi-classical tunnelling approach and the Hamilton–Jacobi method to study Hawking radiation from the dynamical horizon of both the homogeneous Friedmann–Robertson–Walker (FRW) model and the inhomogeneous Lemaitre–Tolman–Bondi (LTB) model of the Universe. In the tunnelling prescription, radial null geodesics are used to visualize particles from behind the trapping horizon and the Hawking-like temperature has been calculated. On the other hand, in the Hamilton–Jacobi formulation, quantum corrections have been incorporated by solving the Klein–Gordon wave equation. In both the approaches, the temperature agrees at the semiclassical level.