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Endogenous molecules, such as heat shock proteins (HSP), can function as danger signals when released into the extracellular environment in response to cell stress, where they elicit an immune response such as cytokine secretion. There has also been some suggestion that contamination of exogenous HSPs with lipopolysaccharide (LPS) may be responsible for these effects. This study investigates the effects of exogenous HSPA1A and HSPB1 on the activation of immune cells and the resulting secretion of cytokines, which are involved in inflammatory responses. To address whether exogenous HSPs can directly activate cytokine secretion, naïve U937 cells, differentiated U937 cells and peripheral blood mononuclear cells (PBMCs) were treated with either exogenously applied HSPA1A or HSPB1 and then secreted IL‐1β, TNF‐α and IL‐10 were measured by ELISA. Both HSPs were able to induce a dose‐dependent increase in IL‐10 secretion from naïve U937 cells and dose‐dependent IL‐1β, TNF‐α and IL‐10 secretion were also observed in differentiated U937 cells and PBMCs. We also observed that CD14 affects the secretion levels of IL‐1β, TNF‐α and IL‐10 from cells in response to exogenous HSP treatment. In addition, HSPA1A and HSPB1 were shown to interact with CD14, CD36 and CD11b extracellular receptor proteins. Several approaches used in this study indicate that HSP‐induced cytokine secretion is largely independent of any contaminating LPS in the samples. [ABSTRACT FROM AUTHOR]

A state‐space model (SSM) of infiltration estimates daily groundwater recharge using time‐series of groundwater‐level altitude and meteorological inputs (liquid precipitation, snowmelt, and evapotranspiration). The model includes diffuse and preferential flow through the unsaturated zone, where preferential flow is a function of liquid precipitation and snowmelt rates and a threshold rate, above which there is direct recharge to the water table. Model parameters are estimated over seasonal periods and the SSM is coupled with the Kalman Filter (KF) to assimilate recent observations (hydraulic head) and meteorological inputs into recharge estimates. The approach can take advantage of real‐time hydrologic and meteorological data to deliver real‐time recharge estimates. The model is demonstrated on daily observations from two bedrock wells in carbonate aquifers of northwestern New York (USA) between 2013 and 2018. Meteorological inputs for liquid precipitation and snowmelt are compiled from SNODAS (2021). Results for recharge during winter and spring seasons show preferential flow events to the water table from liquid precipitation, snowmelt, or a combination of the two. Recharge estimates summed annually are consistent with previous estimates of recharge reported from groundwater flow and surface‐process models. Results from the SSM and KF point to errors in meteorological inputs, such as the snowmelt rate, that are not compatible with hydraulic head observations. Whereas liquid and solid precipitation are measured at discrete stations and extrapolated to 1‐km2 grid cells, snowmelt is a meteorological modeled outcome that may not represent conditions in the vicinity of monitoring well locations. Article Impact Statement: A state‐space model interprets time‐series of water table altitude, precipitation, and snowmelt to estimate groundwater recharge. [ABSTRACT FROM AUTHOR]

Abstract: Field characterization of a trichloroethene (TCE) source area in fractured mudstones produced a detailed understanding of the geology, contaminant distribution in fractures and the rock matrix, and hydraulic and transport properties. Groundwater flow and chemical transport modeling that synthesized the field characterization information proved critical for designing bioremediation of the source area. The planned bioremediation involved injecting emulsified vegetable oil and bacteria to enhance the naturally occurring biodegradation of TCE. The flow and transport modeling showed that injection will spread amendments widely over a zone of lower‐permeability fractures, with long residence times expected because of small velocities after injection and sorption of emulsified vegetable oil onto solids. Amendments transported out of this zone will be diluted by groundwater flux from other areas, limiting bioremediation effectiveness downgradient. At nearby pumping wells, further dilution is expected to make bioremediation effects undetectable in the pumped water. The results emphasize that in fracture‐dominated flow regimes, the extent of injected amendments cannot be conceptualized using simple homogeneous models of groundwater flow commonly adopted to design injections in unconsolidated porous media (e.g., radial diverging or dipole flow regimes). Instead, it is important to synthesize site characterization information using a groundwater flow model that includes discrete features representing high‐ and low‐permeability fractures. This type of model accounts for the highly heterogeneous hydraulic conductivity and groundwater fluxes in fractured‐rock aquifers, and facilitates designing injection strategies that target specific volumes of the aquifer and maximize the distribution of amendments over these volumes. [ABSTRACT FROM AUTHOR]

Konjac glucomannan is a hydrocolloid that has been used in food applications. The European ban on the use of Konjac glucomannan means that the detection and analysis has potential applications in the food industry, particularly detection of food adulteration. The aim of this work was to develop an assay capable of detecting Konjac glucomannan as an isolated sample and within food matrices. An indirect competitive ELISA was developed utilising a polyclonal antibody raised against Konjac glucomannan. The ELISA was found to be specific for Konjac glucomannan and sensitive, with a detection limit of 0.1 ng mL−1. Increasing salt concentration and freeze/thaw cycles did not affect the performance of the assay. The ELISA was able to detect Konjac glucomannan in admixtures with other gums and also in confectionery that had been spiked with Konjac glucomannan. The ELISA has potential as a kit for the differentiation of Konjac glucomannan from other hydrocolloids and detection in food. [ABSTRACT FROM AUTHOR]

A number of enzyme-linked immunosorbent assays (ELISAs) have been developed for the detection of milk adulteration in dairy products. Target antigens have been caseins, lactoglobulins, immunoglobulins and other whey proteins. Polyclonal and monoclonal antibodies have been used in a variety of formats including direct, indirect, competitive and sandwich ELISAs. ELISAs have been successfully applied to the detection of cows' milk adulteration of sheep, goat and buffalo milk. Goat milk adulteration of sheep milk has also been detected. A number of ELISAs have also been applied to cheese. It is recommended that ELISA should be used in combination with PCR to ensure compliance with current legislation. [ABSTRACT FROM AUTHOR]

This paper describes the development and use of a competitive enzyme-linked immunosorbent assay (ELISA) to detect prawns which have been irradiated. The ELISA utilizes a monoclonal antibody against a modified DNA base, dihydrothymidine. A comparison of extraction procedures demonstrated that DNA purification was not required and that crude prawn homogenate could be used in the ELISA. The ELISA was applied successfully to two prawn species, North Atlantic prawn (Pandalus borealis) and Tiger prawn (Penaeus monodon). The ELISA has a working range of 0.5–2 kGy with CVs typically below 10%. Storage of irradiated prawns for up to 12 months at -20 °C had no effect on ELISA performance. As most food contains DNA the assay has potential to be applied in a wide range of foodstuffs. [ABSTRACT FROM AUTHOR]

Evidence from barley [Hordeum distichum (L.) Lam. cv. Maris Mink], and from many other species, suggests that respiration is controlled by either supply of carbohydrate or demand for ATP. The relationship between root respiration rate (measured as O2 consumption or CO2 production) and ethanol-soluble carbohydrate content altered with time following selective pruning, and the change could not be accounted for by buffering of the cytoplasmic carbohydrate concentration by sugars in the vacuole. Exogenous sucrose supplied to the roots prevented any decline of the respiration rate in shoot-pruned plants, and if supplied for 24 h stimulated the respiration rate after any treatment. Root extension responded to sucrose in a similar manner. We suggest that respiration is under fine control by adenylates, but the capacity of the respiratory system is fixed by the supply of sucrose, possibly via coarse control of the respiratory machinery, or of the processes requiring metabolic energy. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) logging provides an efficient method for high-resolution, vertical delineation of electrically conductive contamination in glacial sand-and-gravel aquifers. LM. gamma, and lithologic logs and specific conductance data from sand-and-gravel aquifers at five sites in the northeastern United States were analyzed to define the relation of KM conductivity to aquifer lithology and water quality. Municipal waste disposal, septic waste discharge, or highway deicing salt application at these sites has caused contaminant plumes in which the dissolved solids concentration and specific conductance of ground water exceed background levels by as much as 10 to 20 limes. The major hydrogeologic factors that affected KM log response at the five sites were the dissolved solids concentration of the ground water and the silt and clay content in the aquifer. KM conductivity of sand and gravel with uncontaminated water ranged from less than 5 to about 10 millisiemens per meter (mS/m); that of silt and clay zones ranged from about 15 to 45 mS/m: and that of the more highly contaminated zones in sand and gravel ranged from about 10 to more than 80 mS/m. Specific conductance of water samples from screened intervals in sand and gravel at selected monitoring well installations was significantly correlated with KM conductivity. CM logging can be used in glacial sand-and-gravel aquifer investigations to (1) determine optimum depths for the placement of monitoring well screens: (2) provide a nearly continuous vertical profile of specific conductance to complement depth-specific water quality samples; and (3) identify temporal changes in water quality through sequential logging. Detailed lithologic or gamma logs, preferably both, need to be collected along with the F.M logs to define zones in which elevated EM conductivity is caused by the presence of sill and clay beds rather than contamination. [ABSTRACT FROM AUTHOR]

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