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Abstract Understanding the mechanisms that maintain protective antibody levels after immunisation is important for vaccine design. In this study, we have determined the kinetics of plasma and memory B cells detectable in the blood of cattle immunised with model T-dependent or T-independent antigens. Immunisation with the T-D antigen resulted in an expansion of TNP-specific plasma cells post-TNP primary and booster immunisations, which was associated with increased titres of TNP-specific IgG antibodies. Although no TNP-specific memory B cells were detected in the T-D group following the primary immunisation, we detected an increase in the number of TNP-specific memory B cells post-TNP boost. In contrast, no TNP-specific plasma or memory B cells were detected after primary or secondary immunisation with the T-I antigen. We then investigated if immunisation with a third party antigen (tetanus toxin fragment C, TTC) would result in a bystander stimulation and increase the number of TNP-specific plasma and memory B cells in the T-D and/or T-I group. TTC immunisation in the T-D group resulted in a small increase in the number of TNP-specific plasma cells post-TTC primary immunisation and boost, and in an increase in the number of TNP-specific memory B cells post-TTC boost. This bystander effect was not observed in the animals previously immunised with the T-I antigen. In conclusion, the present study characterised for the first time the B cell response in cattle to immunisation with T-D and T-I antigens and showed that bystander stimulation of an established T-D B cell memory response may occur in cattle.

Abstract Infection of cattle with foot-and-mouth disease virus (FMDV) results in the development of long-term protective antibody responses. In contrast, inactivated antigen vaccines fail to induce long-term protective immunity. Differences between susceptible species have also been observed during infection with FMDV, with cattle often developing persistent infections whilst pigs develop more severe symptoms and excrete higher levels of virus. This study examined the early immune response to FMDV in naïve cattle after in-contact challenge. Cattle exposed to FMDV were found to be viraemic and produced neutralising antibody, consistent with previous reports. In contrast to previous studies in pigs these cattle did not develop leucopenia, and the proliferative responses of peripheral blood mononuclear cells to either mitogen or third party antigen were not suppressed. Low levels of type 1 interferon and IL-10 were detected in the circulation. Taken together, these results suggest that there was no generalised immunosuppression during the acute phase of FMDV infection in cattle.

Basin aquifers are important groundwater sources in the Western United States that are increasingly stressed due to growing populations, increased resource use, and the impacts of climate change. These aquifers are mainly recharged through melting snowpack in the surrounding mountains that infiltrates to the water table and flows directly into the basin (Mountain Front Recharge), or through deeper groundwater pathways that flow from the mountains directly into the basin aquifer (Mountain Block Recharge). However, the dominant system of recharge remains uncharacterized in many mountain basin aquifers. To address this challenge, near‐surface geophysical methods are being implemented to efficiently measure properties that govern groundwater storage and movement. This study infers groundwater storage and recharge to the Casper Aquifer around Laramie, WY, building off past studies that relied solely on sparse monitoring well data and observation of rainfall events. In this study, we use a clustering analysis on airborne electromagnetic data to define hydrogeophysical layers within the Casper Aquifer. These layers, which represent significant changes in bulk subsurface electrical resistivity, are integrated with existing hydrologic, lithologic, and smaller scale geophysical datasets to build a more representative hydrogeophysical model. Through this analysis, we define two sub‐aquifers within the larger Casper Aquifer system that are connected through structurally induced fractures and faults. This research highlights the importance of integrating geophysical data at multiple scales for defining hydrogeophysical layers that provide both a more complete understanding of basin aquifer recharge dynamics and constrain more detailed hydrologic models. Plain Language Summary: Growing populations, increased resource use, and climate change all lead to rising stress on groundwater resources in the Western United States. Groundwater in the western mountain region is generally stored in sedimentary basin aquifers that are understood to be recharged through precipitation that either: (1) infiltrates the water table and then flows directly into the basin, or (2) through deeper groundwater paths that flow from the crystalline cores of the mountains into the basin aquifers. However, relevant recharge systems are uncharacterized in many mountainous aquifers of the Western US. To address this challenge, near‐surface geophysical methods are being used to efficiently measure properties that govern groundwater storage and movement into these basin aquifers. This study uses hydrologic and multiple scale near surface geophysical data (airborne, surface and borehole) as inputs to constrain the storage and recharge dynamics on the Casper Aquifer near Laramie, WY. Integrating lithologic, hydrologic, and geophysical data at fine to large scale, highlights that the Casper Aquifer recharges primarily through snowmelt infiltration atop the nearby Laramie Range, where it flows downslope into the basin until it intersects fracture zone permeability pathways that facilitate movement of groundwater to shallower levels from a deeper primary subsurface aquifer layer. Key Points: Hydrogeophysical layers, distinct by their geophysical properties, are defined through the integration of multi‐scale geophysical dataNew mountain basin, front slope flow recharge regime defined for basin aquifers that outcrop from valley basin to summit of front slopeIntegrating multiscale geophysical data generates more complete understanding of groundwater storage and movement than traditional hydrologic studies [ABSTRACT FROM AUTHOR]

Predicting the hydrological response of watersheds to climate disturbances requires a detailed understanding of the processes connecting hillslopes and streams. Using a network of soil moisture and temperature sensors, electrical resistivity tomography monitoring, and a weather station we assess the above and below‐ground processes driving the hydrological response of a hillslope during snowmelt and summer monsoon. The transect covers bedrock and vegetation gradients, with a steep upper part characterized by shallow bedrock, and gentle lower part underlain by colluvium. The main vegetation cover is conifers on the upper, and grass and veratrum on the lower part. Combined with a simplified hydrological model, we show that the thin soil layer of the steep slope acts as a preferential flow path, leading to mostly shallow lateral flow, interrupted by vertical flow, mostly at tree locations, and likely facilitated by flow along fractures and roots. Vertical flow and upstream‐driven groundwater dynamics are prevailing at the colluvium, presenting a very different hydrological behavior compared to the upper part. These results show that subsurface structure and features have a strong control on the hydrological response of a hillslope and that those can create considerably varying hydrological dynamics across small spatial scales. Key Points: Vegetation, bedrock, and topographic characteristics define hydrological dynamicsShallow lateral flow characterizes steep, shallow bedrockVertical up and downward flow prevails at gentle slope underlain by colluvium [ABSTRACT FROM AUTHOR]

Poisson's ratio for earth materials is usually assumed to be positive (Vp/Vs > 1.4). However, this assumption may not be valid in the critical zone because near Earth's surface effective pressures are low (<1 MPa), porosity has a wide range (0%–60%), there are significant texture changes (e.g., unconsolidated vs. fractured media), and saturation ranges from 0% to 100%. We present P‐wave (Vp) and S‐wave (Vs) velocities from seismic refraction profiles collected in weathered crystalline environments in South Carolina and Wyoming. Our data show that ∼20% of the subsurface has negative Poisson's ratios (Vp/Vs values < 1.4), a conclusion supported by borehole sonic logs. The low Vp/Vs values are confined to the fractured bedrock and saprolite. Our data support the hypothesis that weathering‐generated microcracks can produce a negative Poisson's ratio and that Vp/Vs values can thus provide insight into important critical zone weathering processes. Plain Language Summary: When a material is squeezed, the ratio between the change in height and width is described by an elastic parameter called Poisson's ratio. Most earth materials have a positive Poisson ratio, meaning the material will expand when squeezed (e.g., Playdough or wet sand). Materials with a negative Poisson's ratio rarely occurs naturally and will shrink in all directions when squeezed. Cork is a common material with a Poisson's ratio of approximately zero. Cork is ideal for bottling wine because its width does not change when pushing it into the bottle's narrow neck. Here we use surface‐based measurements to quantify Poisson's ratio from P‐wave (Vp) and S‐wave (vs.) velocities in the top 50 m of Earth's surface. Our results show an unexpected result—material in the CZ has a negative Poisson's ratio. We believe this unexpected behavior is caused by the combination of low effective pressures and small and irregular cracks created during rocks' transformation into soil. The cracks have a greater impact on the material's ability to resist compression. At the same time, most of the rock is still coherent and thus only experiences a minimal loss of shear strength. Key Points: Vp/Vs values in the critical zone can be less than 1.4, suggesting a negative Poisson's ratioIn near‐surface environments, the assumption that materials have a positive Poisson ratio is not always justifiedLow Vp/Vs ratios may identify the onset of physical weathering in crystalline rock [ABSTRACT FROM AUTHOR]

Using replications in discrimination tests is becoming more common in times of strict budgetary and time constraints. For the proof of differences, it is well‐known that the standard binomial test can be used. However, it is no longer applicable if the objective is to show equivalence or non‐inferiority, as potential differences among assessors (assessor heterogeneity/overdispersion) might invalidate the binomial test. We reapply ideas described earlier for the development of a confidence interval to derive a direct asymptotic test for equivalence or non‐inferiority using replicated discrimination and preference data, both for the cases of equal and unequal numbers of replications among assessors. The suggested test is largely model‐free, that is, does not require any assumptions that cannot be easily warranted by the test design and execution. At the same time, implementation is surprisingly easy by using the R code provided or any simple spreadsheet editor, or even manually. Practical Applications: Showing equivalence in perception between stimuli becomes increasingly important in applications, for example, in cost‐savings or product‐matching. The suggested approach is statistically valid without potentially doubtful model assumptions, yet at the same time simple and easy to use. Tables with critical values and R code for the evaluations further ease adoption, as illustrated by three small examples. The power assessments indicate that the loss in power is only moderate as long as the number of replications is not excessive, making replicate evaluations in discrimination tests a viable option for showing equivalence. The common approach of concluding for equivalence when a test for differences does not turn out to be statistically significant is heavily flawed; given that a valid yet simple approach to establish equivalence from replicated discrimination and preference data is provided here, such practice should be abandoned. [ABSTRACT FROM AUTHOR]

The principal focus of this study is an investigation of whether students' grade point average (GPA) is a viable criterion for forming student work groups in the undergraduate Legal Environment of Business course. More specifically, the research focuses on the impact of: (1) GPA-homogeneous (HO) and GPA-heterogeneous (HE) groups upon student satisfaction with group processes and (2) the impact on individual student performance in both group and nongroup assignments. Data obtained from fourteen HE and fourteen HO student groups, in four separate Legal Environment of Business classes consisting of a mix of Management, Marketing, Computer Information Systems, International Business, Financial Services, and Accounting majors, generated a number of significant results. The most surprising observations dealt with the behavior of low achievers whose individual grades showed substantial improvement after working in HO groups. Researchers who are assessing pedagogical methods which serve to engage a student's active learning and motivation should find these results to be of interest. In addition, the beneficial impact on task and relationship behaviors observed in this study should provide solace or a sense of reward to the larger set of academicians, across disciplines, who attempt to impart realistic organizational skills to their classes.

Yellowstone National Park (YNP) is home to roughly 500 geysers, making it the most concentrated geyser field in the world. Recent studies exploring the mechanics of geyser eruptions utilizing laboratory models were limited by a lack of knowledge of the subsurface geometry of the geyser features. This study presents results from active hydrogeophysical surveys, including ground penetrating radar, nuclear magnetic resonance (NMR), seismic refraction, electrical resistivity tomography, and transient electromagnetics to image subsurface geyser structure and constrain the geophysical response of the reservoir structure of Spouter Geyser, Yellowstone National Park. Previous geophysical studies on similar geyser systems in Yellowstone characterize the hydrothermal reservoir that supplies the geyser with hydrothermal fluids and vapors as high porosity, low density structures. Whereas our imaging highlights the hydrothermal conduits and reservoir as high resistivity and high velocity structures, interpreted as silica precipitate decreasing the porosity and increasing the bulk modulus (i.e., from unconsolidated media to semi/fully consolidated). Ground penetrating radar identifies sinter thickness around the geyser, NMR provides porosity measurements of the geyser reservoir, and transient electromagnetics maps the depth to the Biscuit Basin Rhyolite bedrock throughout the field site. Electrical resistivity tomography and seismic refraction image the shallow geyser conduit structures to ∼15 m depth and establish the extent of the geyser hydrothermal reservoir structure. Furthermore, a spatial correlation of the electrical resistivity and seismic velocity results establishes the interpreted hydrothermal geyser reservoir as a high resistivity, high velocity structure located to the northeast of Spouter Geyser at depths greater than 15 m. Plain Language Summary: The dynamics of geyser eruptions are uncertain. Much of this uncertainty stems from a lack of knowledge of their subsurface structure. Therefore, to better understand geyser eruption dynamics, we must first establish the subsurface structure of geysers and their associated hydrothermal geyser reservoirs that supply the erupted hydrothermal fluids and vapors. Geophysical imaging provides an opportunity to image these structures, but active geophysical methods have not been extensively explored for this application. In this study, we use various active geophysical methods to (a) constrain the characteristics of the structure and (b) better understand the subsurface geometry of Spouter Geyser (YNP) and its hydrothermal reservoir. We find that Spouter Geyser's structure and its reservoir have high electrical resistivity and seismic velocity responses, indicative of low porosity and highly cohesive characteristics due to silica precipitate from hydrothermal fluids. We also find that Spouter Geyser's subsurface geometry consists of silica‐lined conduits that extend 15 m to a broad, laterally offset geyser hydrothermal reservoir structure. With the knowledge of the characteristics and geometry of Spouter Geyser and its hydrothermal reservoir, an additional study (Geyser Dynamics II) is better positioned to explore the dynamics of geyser eruptions with active geophysical methods. Key Points: Geophysical results reveal a laterally offset, low porosity and highly consolidated geyser reservoir structure at Spouter GeyserDistinct vertical conduit structures extending to the hydrothermal geyser reservoir at 15 m depth are interpreted at Spouter GeyserVelocity and resistivity distribution characterize Spouter Geyser's reservoir structure as high velocity‐high resistivity [ABSTRACT FROM AUTHOR]

Geysers are unique hydrothermal features, requiring specific geometry, fluid, and vapor input, and heat to produce eruptions. In a geyser eruption, the decompression of superheated hydrothermal fluids results in a conversion of thermal to kinetic energy. Recent studies conclude that a laterally offset cavity structure (bubble trap) plays an integral role in the geyser eruption process. In this second study of Spouter Geyser, Yellowstone National Park (YNP), we build on the geyser structure developed in the first publication and explore how structural components, such as the bubble trap, control eruption dynamics. We utilize time‐lapse electrical resistivity tomography (ERT) and transient electromagnetics (TEM) geophysical methods to track changes in the saturation of conductive hydrothermal fluid and resistive vapor through the eruption cycle. Additionally, we use pressure‐temperature transducer data to measure eruption and recharge durations over the past 23 years at Spouter Geyser, identifying long‐period trends in geyser behavior. The geophysics results support the bubble trap model, capturing an increase in resistivity in the bubble trap structure during the recharge phase interpreted as a vapor saturation increase. The TEM also captures a resistivity increase in the 20–30 m depth interval during the eruption phase, interpreted as a vapor‐dominated "flash eruption zone" where the superheated hydrothermal fluids flash into steam and drive fluid out of this zone during the eruption. From the temperature time‐series detailing 23 years of eruption and recharge durations, we find that eruption durations have remained constant at ∼2 hr while recharge durations have decreased linearly at 6.6 min/year. Plain Language Summary: Current geyser eruption models include a bubble trap structure, a laterally offset, subsurface cavity that pressurizes with hydrothermal fluid and vapor before an eruption. Hydrothermal fluid conducts electrical current more efficiently than hydrothermal vapors, and thus the two phases have different electrical resistivity properties, a measurable geophysical parameter. Here, we pioneer the application of active, time‐lapse electrical and electromagnetic geophysical methods, sensitive to the subsurface electrical resistivity properties, to track hydrothermal fluid and vapor through a geyser system at Spouter Geyser, Yellowstone National Park. Through this, we expand on conclusions of Spouter Geyser's structure (Geyser Dynamics I) by investigating the movement of hydrothermal fluids and vapors to contribute to the understanding of geyser eruption dynamics. We find that electrical resistivity at the top of the geyser hydrothermal reservoir increases while the geyser is not erupting, indicative of vapor buildup in a bubble trap structure. We also find that electrical resistivity increases in a section of the geyser hydrothermal reservoir during the eruption, interpreted as hydrothermal vapors flashing to steam and driving fluids to the surface. Finally, we investigate eruption durations over the past two decades at Spouter Geyser, revealing constant average eruption durations but an increase in eruption frequency. Key Points: Time‐lapse electrical and electromagnetic methods track changes in hydrothermal fluid and vapor saturations in Spouter Geyser's structureTime‐lapse geophysics informs a conceptual model of eruption dynamics at Spouter Geyser that supports the bubble trap geyser modelA 6.6 min/year decrease in Spouter Geyser's average recharge duration over the last 23 years offers insight into long‐duration behavior [ABSTRACT FROM AUTHOR]