The study evaluated effects of dietary administration of Bacillus spp., either single or in combination, on growth performance, immune response and disease resistance in rohu, Labeo rohita (Hamilton) ...fingerlings. The fish were fed for 60 days with control diet (without probiotics) or diets supplemented with 1 × 107 cells g−1 of B. methylotrophicus (E1), B. amyloliquefaciens (E2), B. licheniformis (E3), B. methylotrophicus + B. amyloliquefaciens (E4), B. methylotrophicus + B. licheniformis (E5) and B. amyloliquefaciens + B. licheniformis (E6). Results indicated that combination of B. methylotrophicus and B. licheniformis (E5) produced significant (P < 0.05) improvement in specific growth rate (% d−1), feed conversion ratio and condition factor, when compared to the control and other experimental groups. Immune and blood parameters were examined after 30 and 60 days of feeding. Overall, probiotics supplemented groups (E1-E6) were noticed with improved immune and hematological parameters in comparison to the control group. Serum lysozyme, alternative complements pathway, antiprotease and peroxidase activities were significantly higher in L. rohita reared on conjoint application of probiotics (E4-E6) than other experimental groups (E1-E3, fed single probiotics) and the control group. Further, conjoint application of probiotics significantly increased phagocytic and respiratory burst activities in fish. A significant enhancement in serum IgM level was noticed in the experimental groups after 30 days of feeding, while decreased thereafter. Data on stress enzymes (glutamic oxaloacetic transaminase and glutamic pyruvic transaminase) revealed that probiotics application did not create physiological stress on the fish. Further, after exposure to Aeromonas hydrophila, the highest post-challenge survival (87.33 ± 0.67%) was recorded in fish fed diet E5, which was followed by E6 (78.67 ± 0.88%). Consequently, supplementation of B. methylotrophicus and B. licheniformis in equal proportions might be recommended to improve growth, immunity and disease resistance in L. rohita.
•Efficacy of the gut associated bacilli as probiotics was detected in rohu, Labeo rohita (Hamilton)•Conjoint application B. methylotrophicus and B. licheniformis improved growth, immunity and disease resistance in rohu•Dietary administration of probiotics improved hematological and blood biochemical parameters in fish•Survivability of rohu improved, when challenged with pathogenic Aeromonas hydrophila after feeding probiotics
A complex and dynamic community of microorganisms, play important roles within the fish gastrointestinal (GI) tract. Of the bacteria colonizing the GI tract, are lactic acid bacteria (LAB) generally ...considered as favorable microorganism due to their abilities to stimulating host GI development, digestive function, mucosal tolerance, stimulating immune response, and improved disease resistance. In early finfish studies, were culture-dependent methods used to enumerate bacterial population levels within the GI tract. However, due to limitations by using culture methods, culture-independent techniques have been used during the last decade. These investigations have revealed the presence of
, and
as indigenous species. Numerous strains of LAB isolated from finfish are able to produce antibacterial substances toward different potential fish pathogenic bacteria as well as human pathogens. LAB are revealed be the most promising bacterial genera as probiotic in aquaculture. During the decade numerous investigations are performed on evaluation of probiotic properties of different genus and species of LAB. Except limited contradictory reports, most of administered strains displayed beneficial effects on both, growth-and reproductive performance, immune responses and disease resistance of finfish. This eventually led to industrial scale up and introduction LAB-based commercial probiotics. Pathogenic LAB belonging to the genera
, and
have been detected from ascites, kidney, liver, heart, and spleen of several finfish species. These pathogenic bacteria will be addressed in present review which includes their impacts on finfish aquaculture, possible routes for treatment. Finfish share many common structures and functions of the immune system with warm-blooded animals, although apparent differences exist. This similarity in the immune system may result in many shared LAB effects between finfish and land animals. LAB-fed fish show an increase in innate immune activities leading to disease resistances: neutrophil activity, lysozyme secretion, phagocytosis, and production of pro-inflammatory cytokines (
β
, and
α). However, some LAB strains preferentially induces
instead, a potent anti-inflammatory cytokine. These results indicate that LAB may vary in their immunological effects depending on the species and hosts. So far, the immunological studies using LAB have been focused on their effects on innate immunity. However, these studies need to be further extended by investigating their involvement in the modulation of adaptive immunity. The present review paper focuses on recent findings in the field of isolation and detection of LAB, their administration as probiotic in aquaculture and their interaction with fish immune responses. Furthermore, the mode of action of probiotics on finfish are discussed.
A methyl phenyl sulfoximine (MPS) is used as a directing group in the ruthenium‐catalyzed intramolecular hydroarylation of alkene‐tethered benzoic acid derivatives to afford dihydrobenzofurans and ...indolines in good to excellent yields. A one‐pot, unsymmetrical, twofold C−H functionalization involving intramolecular C−C and intermolecular C−C/C−N bond formations is successfully demonstrated by using a single set of catalytic reaction conditions, which is unprecedented thus far. A novel isoquinolone‐bearing dihydrobenzofuran is constructed through an unsymmetrical twofold C−H functionalization.
In a single shot: A methyl phenyl sulfoximine (MPS) is used as a directing group in the ruthenium‐catalyzed intramolecular hydroarylation of alkene‐tethered benzoic acid derivatives to afford dihydrobenzofurans and indolines in excellent yields. A one‐pot, unsymmetrical, twofold C−H functionalization involving intramolecular C−C and intermolecular C−C/C−N bond formations is successfully demonstrated.
The heating or cooling performance of convective thermal systems is critically dependent upon their geometrical shapes/configurations apart from other controlling aspects. Here, an effort is made to ...address the shape impact on thermal performance, using square and circular systems under the classical differentially heating configuration. The comparison of systems’ performance is made by applying the constraints of identical fluid volume, heating and cooling surfaces, and cavity inclinations for both systems. The study covers mostly used practical working fluids namely air, water, and a water-based nanofluid. For such a type of thermal system analysis, the numerical approach is chosen appropriately to generate a huge volume of the solved results. The Prandtl number, Rayleigh number, the nanofluid concentration, and cavity orientation are used as the system parameters, and the study reveals a strong impact of the cavities’ shapes. In general, the thermal performance and evolved circulation (due to the differential heating) are found superior with the circular cavity over its equivalent square cavity configuration. The analysis confirms that the geometric modification is a better choice for achieving superior heat transfer; the heat transfer enhancement could be up to
∼
22.21
%
(when the cavity is horizontal), 24.11% (with inclined cavity) with air as a working medium. There is a further enhancement on heat transfer with the modified circular cavity up to 2.76% (with horizontal cavity), 15.19% (with inclined cavity) using nanofluid. The heat flow dynamics from the heating side to the cooling side are also explored using the Bejan’s heatlines. The outcome of this study will help the designer to model the thermal device considering various controlling aspects from an appropriate thermal management point of view.
In the present work, a study has been made over the prime stock indices of some fiscally prominent countries impacted by COVID-19. The countries are separated in two ways: (1) considering gross total ...number of infected cases—here seven mostly impacted countries with certain global economic influence are selected; (2) considering the concentration of the infected cases—here six major impacted countries with considerable influence are selected. This sort of categorization is itself a novel strategy which is capable of including some less populated, but severely impacted countries of economic importance. The objective of the present analysis is to comprehend the impact of COVID-19 on these markets and to recognize the effect of COVID-19 on mutual association and dependence between these markets. To add more flavour of reliability, we have taken a new and fresh strategy of fixing the time frames under consideration before and during COVID-19 pandemic as uniform. We have used both linear and nonlinear Granger causality analysis and employed generalized forecast error variance decomposition analysis to review the exogeneity and endogeneity of the individual markets. The present study shows that this pandemic has changed the underlying relationship: some exogenous stock markets have become endogenous and vice versa in the pandemic. Linear relationship has been reduced radically, whereas nonlinear relationship has been improved during the COVID-affected period. TASE, the highest returned and significantly uncorrelated index, emerged as the most exogenous market in the pre-COVID period, though it is nonlinearly endogenous in the long term, in the COVD-affected period. CAC 40 is the most endogenous market for the short term in both pre-COVID and COVID-affected period. B3 and NYSE, exogenous in the pre-COVID period, turned out to be linearly endogenous in the COVID-affected duration, whereas BIST 100 and BSE SENSEX are found to be exogenous markets in the COVID-affected period according to both linear and nonlinear causal analysis. They were also exogenous in the pre-COVID era for the short-term period, with BSE SENSEX exhibiting exogeneity anti-persistently for the COVID-affected period too. Association among the markets is more in long term rather than short term. A possible conclusion is also that the markets may regain long-term association once the effect of COVID would fade away.
The present paper presents an overview of the effects of gut microbiota and probiotics on lipid-, carbohydrate-, protein- and amino acid metabolism in fish and shrimp. In probiotic fish studies, the ...zebrafish (Danio rerio) model is the most frequently used, and probiotic administration reveals the effect on glucose homeostasis, anti-lipidemic effects and increasing short-chain fatty acids, and increased expressions of genes related to carbohydrate metabolism and innate immunity, along with down-regulation of oxidative stress-related genes. Further, improved length of the intestinal villi and expression of nutrient transporters in fish owing to probiotics exposure have been documented. The present review will present an appraisal of the effect of intestinal microbiota and probiotic administration on the metabolism of nutrients and metabolites related to stress and immunity in diverse fish- and shrimp species. Furthermore, to give the reader satisfactory information on the topics discussed, some information from endothermic animals is also presented.
Effective removal of heat from the heat-generating porous bed, particularly in a confined space, is essential due to its implications on thermal management and system safety. The safety aspect ...becomes particularly important during post-accident heat removal from decay heat-generating debris in nuclear reactors, as well as thermal management of self-igniting coal stockpiles. In spite of detailed research on thermal convection through porous media, only a handful of studies have considered mixed convective heat transport involving heat-generating porous bed along with external fluid injection. The situation, however, demands an in-depth analysis due to the associated practical implications. The present work addresses one cooling method providing side injection of cold fluid and assuming a typical conical heat-generating porous bed located centrally within a fluid-filled cylindrical enclosure. The study is carried out in a general way to suit other applications. The dimensionless governing equations, along with the boundary conditions in a two-dimensional coordinate system, are solved numerically assuming laminar and incompressible flow along with the Boussinesq approximation. The analysis is carried utilizing the local thermal non-equilibrium model within the porous bed. Injection of cold fluid can markedly affect the convective heat transport rate. Porous media permeability considerably influences the flow mechanism. The major findings of this study can be very useful in improving the management of thermal energy removal from self-igniting coal stockpiles, grain storages, porous debris, etc. Heat transport intensification from heat-generating porous bed is analyzed by injecting coolant through the sidewall and considering liquid water as the working medium. The impacts of pertinent parameters on the thermal convection characteristics are illustrated using the average Nusselt number and energy flux vectors.
Discussed herein is an unprecedented Ru-catalyzed one-pot unsymmetrical C–H difunctionalization of arenes comprising intramolecular hydroarylation of olefins and intermolecular annulation of alkynes. ...This unprecedented 2-fold C–H functionalization is validated on the basis of experimental and density functional theory (DFT) study. The transformation readily occurs with the assistance of methylphenyl sulfoximine (MPS) directing group in the presence of Ru catalyst forming two C–C and one C–N bonds in a single operation. The overall process is atom economical and step-efficient and provides unusual dihydrofuran-fused isoquinolone heterocycles. Further annulation of NH and the proximal o-C–H-arene of isoquinolone with alkynes build highly conjugated novel polycyclic compounds. Overall, three independent annulations in arene motifs are visualized and thoughtfully executed; finally, 5 ring-fused structural entities are constructed forming three C–C and two C–N bonds.
A novel approach toward the construction of multicomponent two-dimensional (2-D) and three-dimensional (3-D) metallosupramolecules is reported. Simply by mixing carboxylate and pyridyl ligands with ...cis-Pt(PEt3)2(OTf)2 in a proper ratio, coordination-driven self-assembly occurs, allowing for the selective generation of discrete multicomponent structures via charge separation on the metal centers. Using this method, a variety of 2-D rectangles and 3-D prisms were prepared under mild conditions. Moreover, multicomponent self-assembly can also be achieved by supramolecule-to-supramolecule transformations. The products were characterized by 31P and 1H multinuclear NMR spectroscopy, electrospray ionization mass spectrometry, and pulsed-field-gradient spin echo NMR techniques together with computational simulations.
The objective of the present work is to evaluate the performance of the evaporator tubes of a natural circulation boiler under different operating pressure and heat flux. A significant concern of the ...present work is assessing the dry-out/critical heat flux limit and the critical circulation ratio (CR) of an existing evaporator downcomer system of a natural circulation boiler. The analysis of these parameters is crucial from a safe operation perspective. To carry out the study, three two-phase flow models, namely homogeneous flow model (HFM), separated flow model (SFM), and drift-flux model (DFM), are developed. The sensitivity of the models on various thermo-hydraulic parameters, change of flow regime, and circulation ratio is assessed. A rigorous validation exercise is carried out for a host of experimental, numerical, and plant design data pertaining to two-phase flow thermosyphon. The results indicate that the safe circulation ratio at low (< 40 bar) and intermediate (40–80 bar) pressure predicted by HFM is relatively high and differs substantially from the two other models. However, beyond 80 bar pressure (high operating pressure), the CR predicted by different models is considerably less and in closer agreement with each other. The practical boiler performance studies with different capacities indicate that the maximum difference of critical heat flux predicted by different models for boilers of different capacities lies within a 15% margin. These data will help the engineers associated with boiler operation and the associated persons with the boiler design sector.
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