The peristaltic transport phenomenon is due to the alternative process of contraction and relaxation of the channel walls, and the pumping process is exhibited from the fluid with lower pressure ...region to higher within the wavy channel. A simulation is carried out for an electrically conducting micropolar nanofluid within a wavy channel for the interaction of radiative heat energy and the heat source/sink. The conducting fluid comprised of the Brownian and thermophoresis forms a Buongiorno model nanofluid. The crux of this investigation is to bring out the analysis of the irreversibility process due to heat transfer with entropy generation. The impact of Joule heating characterizes within the upper/lower zeta potentials is also affecting the flow phenomena. However, the exploration on these concerns will offer a profound perceptive of peristaltic rheology in more realistic circumstances. Approximate analytical technique, i.e., Differential Transformation Method (DTM) is used to get the desired solution of the set of transformed governing equations using the in-built MATLAB code bvp4c. Further, the analysis of characterizing parameters involved in the flow phenomena is obtained and deployed via graphs. The highlighted outcomes are: the non-Newtonian characteristics are dominated by the Newtonian fluid for irrespective of the appearance/non-appearance of the micropolar parameter however, Brinkman number enriches the entropy due to the irreversibility in the thermal processes.
Edwardsiella tarda is an important Gram-negative bacterium that causes systemic infections in a wide range of hosts including fish. The pathogenic mechanisms in this disease are still poorly ...understood in fish. Indian major carp,
Labeo rohita were intraperitoneally challenged with a pathogenic isolate of
E. tarda to measure sequential changes in immunity level. A significant decrease in the superoxide production, myeloperoxidase, alternative complement activity, total protein levels and antiprotease activity of serum was marked in the infected fish. However, the serum lysozyme activity and haemagglutination titre were raised in the infected fish. Similarly, a significant rise in specific antibody titre was noticed on and after 10 days post-challenge. This study also elucidates the changes in the relative expression of some immune-related genes viz., interleukin 1-beta (IL-1β), inducible nitric oxide synthase (iNOS), complement component C3, β
2-microglobulin, CXCa, tumor necrosis factor-alpha (TNFα), and C-type and G-type lysozymes during the infection. Significant up-regulation of IL-1β, iNOS, C3, CXCa and expression of both types of lysozyme genes was noticed at 6–12 h post-challenge (h.p.c.) whereas down-regulation of β
2-microglobulin and TNFα genes was observed after 48 h p.c. The results obtained here strengthen the understanding on molecular pathogenesis of edwardsiellosis in
L. rohita.
PurposeIn the paper, the authors study the simultaneous influence of incentive compatibility and individual rationality (IR) on a multi-echelon supply chain (SC) under uncertainty. The authors study ...the impact of contract sequence on coordination strategies of a serial three-echelon SC consisting of a supplier, a manufacturer and a retailer in an uncertain environment.Design/methodology/approachThe authors develop a game-theoretic framework of a serial decentralized three-echelon SC. Under a decentralized setting, the supplier and the manufacturer can choose from two contract types namely, wholesale price (WP) and linear two-part tariff (LTT) and it leads to four different cases of contract sequence.FindingsThe study show that SC coordination is possible when both the supplier and the manufacturer choose LTT contract. This study not only identifies the influence of contract sequence on profit distribution among SC agents, but also establishes cut-off policies for all SC agents for each contract sequence. This study also examine the influence of chosen contract sequence on optimal profit distribution among SC agents.Research limitations/implicationsThree-echelon SC coordination under uncertain environment depends upon the contract sequence chosen by SC agents.Practical implicationsThis study results will be helpful to managers of various SCs to take operational decisions under uncertain situations.Originality/valueThe main contribution of this study is that it explores the possibility of coordination by supply contracts for three-echelon SC in a fuzzy environment.
Understanding groundwater storage variations as a result of effects from both the vadose zone and the river is of critical importance in the hydraulically connected surface‐subsurface system. In this ...study, we present a novel Bidirectional Exchange Scheme in Surface and Subsurface (BE3S) that represents bidirectional exchanges between the vadose zone, phreatic aquifer, and river. The approach enables explicit representations of each flow regime while conserving mass, and successfully yields solutions of the coupled system for multiple temporal resolutions. We test the scheme by comparing the BE3S‐derived outputs against other models and corresponding observational data. We apply the scheme to simulate hydrologic states in a reach of the Brazos River in Southeast Texas, such as soil moisture content, groundwater level, and river stage as well as net subsurface discharge fluxes. Good agreements between the simulated and observed data for all the components show the suitability of the proposed scheme in modeling the bidirectional flows and exchanges. We also assess how the bidirectional hydrologic exchanges are affected by adjacent flow domains. We find that vertical percolation is significantly affected by unsaturated soil thickness, resulting in the spatial variability of vertical percolation across sloping topography. Hilltop‐to‐valley convergent groundwater flow is also found to impede vertical percolation in river valleys due to shallow water table while facilitating percolation in the hilltops. The capability of the presented scheme that accounts for the topographically driven lateral groundwater flow and drainage dynamics provides the potential to enhance the representation of the surface‐subsurface system in Earth System Models (ESMs).
Plain Language Summary
The hydrologic systems that comprise the Earth's surface and subsurface are linked and influence each other. Understanding how the systems interact is, therefore, essential to predict the hydrologic state of each flow system. The hydrologic interactions can be evaluated by quantifying exchange fluxes between adjacent flow domains. The characteristics of different flow systems can be modeled by the governing equation corresponding to each system, Besides, it is still necessary to clarify how could the time‐varying state of surface and subsurface waters due to the hydrologic/climatic forcing affect the direction and amount of exchange flux. We propose a novel numerical scheme to simulate the simultaneous interactions among vadose zone‐phreatic aquifer‐river on a sloping topography. The scheme is tested with a river reach of the Brazos River in southeast Texas as a case study and proved to have the successful capability to simulate hydrologic states such as soil moisture content, groundwater level, and streamflow as well as exchange fluxes. Our approach explicitly considers the mutual effects between a topographically‐driven drainage system and lateral groundwater flow. Overall, the presented modeling framework can be a viable tool to understand the interactive flows among different hydrologic systems in a linked fashion.
Key Points
Development and verification of a novel numerical scheme to represent bidirectional exchanges between the vadose zone, aquifer, and river
Topographically driven convergent groundwater flow and its effects on vertical percolation are explicitly represented on catchment scale
Combinational effects of the vadose zone and the river on groundwater vary by distance from the river, connectivity, and topography
Although hydraulic groundwater (GW) theory has been recognized as a promising tool for understanding the role of the aquifer(s) in the surface‐subsurface hydrologic cycle, the integrated modeling ...community still lacks a proper hydrologic structure to apply the well‐studied theory to large‐scale hydrologic predictions. This study aims to present a novel hydrologic structure that enables the Boussinesq equation‐based depiction of the bidirectional stream‐hillslope processes for applying hydraulic GW theory to large‐scale model configurations. We integrated the BE3S's (Hong et al., 2020, https://doi.org/10.1029/2020wr027571) representation scheme of the catchment‐scale stream‐hillslope continuum into the National Water Model (NWM) and applied the modified NWM (i.e., the NWM‐BE3S) to three major basins in Texas (i.e., the Trinity, Brazos, and Colorado River basins). Since the NWM currently relies on a single reservoir model for baseflow simulation, we used the Boussinesq aquifer as an alternative subsurface hydrology routine and evaluated its predictive skill and efficacy. We identified that the implemented Boussinesq aquifer(s) in the NWM‐BE3S yielded noticeable improvements in predicting streamflow for aquifers that exhibited higher nonlinearities in the observed recessions. The varying degree of improvements in streamflow predictions per the recession nonlinearities demonstrated not only (a) the algorithmic enhancement of subsurface hydrology (physics) but also (b) the applicability of the Boussinesq theory‐based depiction of the stream‐hillslope two‐way continuum. We diagnosed each stream's state based on the bidirectional stream‐hillslope exchanges and identified the dominant processes (i.e., river infiltration or baseflow) that were represented spatially in the NWM‐BE3S.
Plain Language Summary
Streamflow is a critical land hydrologic component to manage water resources and the health of the associated ecosystem. While the water cycle between the stream and hillslope is the key process to accurately simulating streamflow, most currently used hydrologic/land surface models lack a theoretical basis to characterize the catchment‐scale groundwater to depict the stream‐hillslope water cycle. In this paper, we presented a new structure NWM‐BE3S that enables the Boussinesq approximation‐based characterization of the catchment(s) for improving the predictability of streamflow. The NWM‐BE3S was developed by integrating a recent numerical scheme BE3S (Hong et al., 2020, https://doi.org/10.1029/2020wr027571) into the WRF‐Hydro National Water Model (NWM) configuration as an alternative subsurface routing routine. The NWM‐BE3S was tested against streamflow observations from three major basins in Texas (i.e., the Trinity, Brazos, and Colorado River basins) to ensure the applicability of the Boussinesq‐based stream‐hillslope continuum scheme. We identified theory‐consistent improvements in the streamflow predictions from the NWM‐BE3S framework compared to the original NWM. Based on the two‐way fluxes modeled from the hydraulically continuous catchment(s) in the NWM‐BE3S, moreover, about 10% of the river reaches in the three basins were identified as losing streams during the evaluation period.
Key Points
The Boussinesq theory‐based stream‐hillslope two‐way hydrologic interactions were newly introduced in the National Water Model (NWM)
The Boussinesq aquifer yielded improved streamflow predictions than the single bucket model as the nonlinearity of recession increases
Gaining or losing reaches in three Texas major basins showed improved predictions using the modified NWM
The postoperative period after craniopharyngioma surgery has a high likelihood of complications and its management can be challenging. We present the case of a 10-year-old boy who was operated for ...craniopharyngioma. In the postoperative period he developed lacunar infarct, endocrine disturbances, delayed vasospasm leading to cerebral infarction and status epilepticus. The likely cause of status epilepticus was likely delayed cerebral infarction compounded with dyselectrolytemia. We discuss the possible etiology of delayed cerebral infarction.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
To investigate the dynamic fracture mechanism related to blast-induced borehole breakdown and crack propagation, circular rock models containing a single centrally located source of explosive were ...numerically blasted using the AUTODYN 2D code. According to the material properties and loading conditions, four kinds of equations of state, linear, shock, compaction and ideal gas, are used. A modified principal stress failure criterion is applied to determining material status. The dynamic stresses at the selected target points in a rock sample are computed as a function of time following application of explosive load. It is shown that shear stress (resulting from intense compressive stress) causes a crushed zone near the borehole, the major tensile principal stress causes radial cracks, and the reflected stress wave from free boundary causes circumferential cracks some distance away from the free boundary. The influences of the factors of boundary condition, coupling medium, borehole diameter, decoupling and joint on rock dynamic fracture are discussed.
Edwardsiellosis is one of the most important bacterial diseases in fish. Scientific work on this disease started more than forty years ago and numerous workers around the world are continually adding ...to the knowledge of the disease. In spite of this, not a single article that reviews the enormous scientific data thus generated is available in the English language. This article briefly discusses some of the recent research on edwardsiellosis, describing the pathogen's interaction with the host and environment, its pathogenesis and pathology as well as diagnostic, preventive and control measures.
This paper presents the observations of the study on arsenic removal from a contaminated ground water (simulated) by adsorption onto Fe3+ impregnated granular activated carbon (GAC-Fe). Fe2+, Fe3+ ...and Mn2+ have also been considered along with arsenic species in the water sample. Similar study has also been done with untreated granular activated carbon (GAC) for comparison. The effects of adsorbent dose, particle size of adsorbent and initial arsenic concentration on the removal of As(T), As(III), As(V), Fe2+, Fe3+ and Mn2+ have been discussed. Under the experimental conditions, the optimum adsorbent doses for GAC-Fe and GAC have been found to be 8g/l and 24g/l, respectively with an agitation time of 15h. Particle size of the adsorbents (both GAC and GAC-Fe) has shown negligible effect on the removal of arsenic and Fe species. However, for Mn removal the effect of adsorbent particle size is comparatively more. Percentage removal of As(T), As(V) and As(III) increase with the decrease in initial arsenic concentration (As0). However, the increase in percentage removal of all the arsenic species with decrease in As0 are less for higher value of As0 (3000-500ppb) than those of the lower value of As0 (500-10ppb). The % removal of As(T), As(III), As(V), Fe, and Mn were 95%, 92.4%, 97.6%, 99% and 41.2%, respectively when 8g/l GAC-Fe was used at the As0 value of 200ppb. However, for GAC these values were 55.5%, 44%, 71%, 98% and 97%. The pH and temperature of the study were 7+/-0.1 and 30+/-1 deg C, respectively.
Abstract
Based on an empirical exercise carried out in five villages of Odisha in eastern India, the paper looks into ageing of the farm population and the experiences and responses of farmers of ...various age groups to farming. The findings of the study indicate that agriculture is greying, farmers are getting older and the youth, particularly of higher and cultivating castes, are averse to farming. The unwillingness of these youths to join farming is mainly attributed to loss of social status, declining profitability in agriculture and discouragement of immediate ‘mentors’, the middle‐aged farmers, caused by the perpetual decline of farm income and loss of social recognition. The hitherto nonfarming youths, belonging to scheduled castes, scheduled tribes and service‐rendering castes, especially the female youths, are joining farming to fill this gap, mostly as leased‐in cultivators.
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