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Buried bedrock valleys are common erosional features in northern mid-latitude environments that form through glaciofluvial or paleoalluvial processes and are typically infilled by Quaternary-aged sediments. The erosional extent and geometry of the valley including a weathered interface, along with sediment infill that can contain complex sequences of unconsolidated aquifer and aquitard sediments, mean these features may act as preferential pathways to deeper bedrock aquifers. Noninvasive geophysical tools can provide rapid, high-resolution subsurface characterization of these features. This study evaluates the application of electrical resistivity and seismic refraction tomography along two transects centred over a buried bedrock valley in Elora, Ontario, Canada. Geophysical measurements were combined with existing continuous core records and an electrofacies model based on downhole geophysical logs to constrain the morphology and infilled lithostratigraphic architecture of the valley. Bedrock competency associated with lithology may act as a control on depth and width of valley incision during erosion, with resistivity measurements of the bedrock revealing a potential association between interpreted mechanical properties and variations in the resolved valley morphology. Seismic velocity corroborated these contrasting valley widths but could not assess bedrock competency variability below the bedrock interface. This study reveals the sequence of events depositing sediments in the valley, yielding a revised architectural mapping that improves on previous regional scale lithostratigraphic interpretations. Results will be of use to groundwater practitioners requiring detailed conceptualization of this buried bedrock valley and its role on preferential zones of groundwater flow. Similar approaches can be used for delineation of these common and hydrogeologically significant features.

Microscopy slides are routinely created as part of sexual assault workflows for screening purposes and retained indefinitely with instances, such as cold cases, where they are the only remaining source of evidence. To date, no method has been developed to harvest the cells from these slides for differential extraction using the i-sep® DL column or Intimate extraction using the PrepFiler™ Express chemistry supplemented with 60 mM DTT. This study used mock sexual assault slides from 2010 to develop a potential cell harvesting method, then tested both the extraction methods on historic casework slides collected in the 1980s and 1990s. Key findings included the necessity to re-screen slides microscopically to assess current cellular loading and the utility of using phase contrast to enhance visualisation of spermatozoa on historic slides. Both extraction methods successfully recovered DNA and generated partial profiles from the 1990s slides, but 1980s slides were too degraded to provide informative profiles. Differential extraction provided additional contextual information by separating contributors into sperm and non-sperm fractions, resulting in cleaner sperm profiles for interpretation. The study successfully established methods for historic microscope slides to be used as viable sources of evidence, potentially aiding in the progression and resolution of sexual assault investigations.

The Liard Basin, in northwestern Canada, contains one of Canada’s largest natural gas reserves. There are concerns about degradation of Dunvegan Formation groundwater quality, which is the basin's main shallow freshwater aquifer, as a consequence of oil and gas development. Previous lithostratigraphic studies interpreted the Dunvegan as conglomeratic alluvial fans. In this study, newly collected cores and surface resistivity surveys are integrated with legacy hydrocarbon well data and measured sections for improved sedimentary bedrock characterization. Rather than alluvial fans, we interpret the upper Dunvegan as a coarse-sand to gravel bed fluvial system that was likely tributive to incised valleys associated with linked Alberta Basin base-level falls. Correlation of well logs and measured sections suggest the lower Dunvegan comprises a prograding delta complex with off-lapping clinoforms fed by smaller sand-bed rivers that grade into the upper Dunvegan conglomeratic system, which built southeast towards the Cretaceous Western Interior Seaway. This sequence stratigraphic and facies architectural approach is employed to inform the aquifer–aquitard flow system and aid in understanding the 3D groundwater flow system, once hydrogeologic characterisation confirms position and thickness of important hydrogeologic units. Resistivity surveys suggest upper Dunvegan channel-belt facies may be well-connected and laterally extensive, potentially acting as interconnected aquifer units; whereas lower Dunvegan channel belts may be discontinuous, indicating smaller-scale flow units separated by floodplain and marine shale. This revised geologic understanding provides opportunities for determining impacts or resilience from shallow and deep sources of contamination associated with human activities, including oil and gas development, land-use, and (or) climate change.

The PrepFiler™ BTA Forensic DNA Extraction Kit (BTA) is designed to purify DNA from challenging forensic samples including tissue, bone, tooth and adhesive-containing substrates. Earlier versions of the manual state that lysates are stable at ambient temperature for 24 h when 300 µL of PrepFiler™ lysis buffer is added to the lysate. The effect of centrifuging additional PrepFiler™ lysis buffer over PrepFiler™ BTA-lysed remnants has not been evaluated previously. This study evaluated the DNA yield and STR profile quality of BTA lysates after 24 h with or without PrepFiler™ lysis buffer addition over sample remnants. Blood, semen and buccal cells on tape were processed with 300 µL of PrepFiler™ lysis buffer added directly to spun lysates (standard) or over sample remnants (top-up), and DNA extracted immediately or 24 h after lysis. The top-up method generated higher DNA yields for all tape samples tested, with diluted semen returning the greatest improvement. Comparison of standard and top-up methods for chewing gum, tissue and tooth samples showed that cigarette butt remnants must be removed prior to top-up to maintain resultant DNA quality. The top-up method maximizes DNA recovery using Prepfiler™ BTA, while enabling the combination of PrepFiler™ BTA and PrepFiler™ lysates DNA purification batches for high-throughput applications.

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Purpose: Chronic lymphocytic leukemia (CLL), a malignancy of mature B cells, is incurable with chemotherapy. Signals from the microenvironment support leukemic cell survival and proliferation and may confer chemotherapy resistance. ON 01910.Na (Rigosertib), a multikinase phosphoinositide 3-kinase (PI3K) inhibitor, is entering phase III trials for myelodysplastic syndrome. Our aim was to analyze the efficacy of ON 01910.Na against CLL cells in vitro and investigate the molecular effects of this drug on tumor biology.Experimental Design: Cytotoxicity of ON 01910.Na against CLL cells from 34 patients was determined in vitro with flow cytometry of cells stained with Annexin V and CD19. Global gene expression profiling on Affymetrix microarrays, flow cytometry, Western blotting, and cocultures with stroma cells were used to delineate ON 01910.Na mechanism of action.Results: ON 01910.Na induced apoptosis in CLL B cells without significant toxicity against T cells or normal B cells. ON 01910.Na was equally active against leukemic cells associated with a more aggressive disease course [immunoglobulin heavy-chain variable region unmutated, adverse cytogenetics] than against cells without these features. Gene expression profiling revealed two main mechanisms of action: PI3K/AKT inhibition and induction of ROS that resulted in an oxidative stress response through activating protein 1 (AP-1), c-jun-NH2-terminal kinase, and ATF3 culminating in the upregulation of NOXA. ROS scavengers and shRNA mediated knockdown of ATF3- and NOXA-protected cells from drug-induced apoptosis. ON 01910.Na also abrogated the prosurvival effect of follicular dendritic cells on CLL cells and reduced SDF-1–induced migration of leukemic cells.Conclusions: These data support the clinical development of ON 01910.Na in CLL. Clin Cancer Res; 18(7); 1979–91. ©2012 AACR.

Geophysical methods have the capacity to detect and characterize gas-phase dynamics in groundwater. Suitable methods can be deployed at surface or within boreholes depending on the required depth of investigation, spatial/temporal resolution, and geologic conditions. While the application of geophysical methods to monitor immiscible phase contaminants in the subsurface has been extensively documented, the effects of hydraulic properties and flow system conditions on the nature of the geophysical responses used to elucidate multi-phase fluid flow remains underdeveloped. A series of numerical 2-dimensional multi-phase flow and geophysical model simulations based on a controlled methane release experiment in the Borden unconfined sand aquifer was carried out to assess the influence of porous media hydraulic properties and flow system conditions on geophysical signatures associated with transient gas-phase saturation and gas migration behaviour. Specifically, the utility of electrical resistivity tomography (ERT) and ground-penetrating radar (GPR) to monitor gas-phase plume dynamics in shallow groundwater flow systems is examined. ERT and GPR responses to gas-phase distribution and migration during a 72-day methane gas injection and subsequent recovery period was calculated using a numerical multi-phase flow model (CFbio) simulating four distinct parameterizations of the sandy aquifer system. Geophysical models showed that ERT was effective at imaging the central position of the plume but was less effective at detecting thinner lateral migration pathways extending beyond the primary high gas saturation bulb. Conversely, GPR was able to detect thin gas pools emanating from the primary gas bulb and small-scale vertical preferential pathways arising from capillary boundaries with contrasting saturations; however, gradational boundaries proved to be more difficult to resolve using GPR. This study demonstrates that ERT and GPR can be very useful tools in combination for longer-term monitoring of stray gas leakage from decommissioned hydrocarbon wells in shallow granular media freshwater aquifers, especially given the likelihood of strong lateral migration.

Technology‐mediated simulation is often used in medical problem‐based learning (PBL) approaches to offer authentic contexts and immersive engagement for learning. However, critiques argue that these approaches are lacking in the structure necessary to support productive learning—that they often result in mindless doing without the thinking processes needed that lead to deeper understanding and expertise. This paper presents data from a technology‐mediated simulation, called HMS MEDscience, to demonstrate: (1) that it effectively leads to greater expert reasoning—evident through responses in content knowledge and problem‐solving ability that more closely aligned with a rubric of expert responses to the same questions; (2) through a series of case studies, the implicit pedagogical moves the teachers make to support students' thinking processes. Significant pre‐ to posttest gains indicate more expert reasoning. In addition, classroom videos indicate shifts from novice toward more expert medical science reasoning and illustrate the fine‐grained supporting moves that teachers use to guide students' thinking toward more expert understanding of the problem space. This study highlights the importance of the thinking processes that students engage in as they participate in technology‐mediated PBL and the accompanying teacher attention to student thinking through supporting pedagogical moves. Practitioner NotesWhat is already known about this topic Technology‐mediated problem‐based learning (PBL) can invite an immersive experience for learners to engage with authentic problems.Broad framing for effective PBL includes features such as structured group work, a tutorial process for structuring knowledge and action plans, constructive investigation, and cognitive mentorship.The results on PBL have been mixed depending upon how it is enacted. It typically takes very skilled teachers and additional inherent structure.What this paper adds It demonstrates that novice‐expert shifts are possible in high school students' reasoning about technology‐supported, medical‐based problem solving.It reveals six nuanced thinking scaffolds that teachers used to support students' shift toward the more expert conceptions.It identifies seven thinking moves that students engaged in during the problem‐solving context.Implications for practice and/or policy It alerts practitioners to the need to attend to the pedagogical moves that they employ to support student thinking.It demonstrates the importance of the thinking processes that students engage in as they participate in technology‐mediated PBL.It demonstrates that successful learning in technology‐mediated PBL contexts is accompanied by teacher attention to student thinking and supporting pedagogical maneuvers. [ABSTRACT FROM AUTHOR] uracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dinickel complexes promote stoichiometric Pauson–Khand reactions of enynes and CO (g). However, catalytic turnover is precluded by the strong binding of CO to the Ni2 active site. This article describes the use of M(CO)x reagents as stoichiometric CO precursors in Ni2-catalyzed carbonylation reactions. As part of these studies, well-defined heterotrinuclear Ni2Fe, Ni2Co, and Ni2Mn carbonyl clusters are synthesized using the [NDI]Ni2 platform as a template (NDI = naphthyridine–diimine).

Creating a geological framework for hydrogeological investigations in ice-marginal settings is challenging, as the dynamic nature of ice margins results in heterogeneous sediments and complex geometries that are difficult to characterize geologically and hydraulically. In this study, a multi-scale and multi-tool approach was used to develop a robust and hydraulically calibrated conceptual model of a site in Wisconsin (USA), which constrains the subsurface geologic and hydraulic heterogeneity onsite and can be utilized offsite and in similar settings. Facies analysis, including detailed logging of sediment cores integrated with geophysical surveys, was used to reconstruct the glacial history of the site and to identify key sedimentation styles. Depth-discrete multilevel monitoring wells were used to measure hydraulic head and to explore the relationship between hydraulic conditions and stratigraphy. Results indicate that hydraulic and geological heterogeneity do not necessarily coincide, as hydraulic head profiles of the heterogeneous sediments showed little head change with depth. The minimal observed hydraulic heterogeneity in this complex geologic system is likely due to relatively small and spatially limited differences in hydraulic conductivities, limited water-table relief, and minimal natural or induced transience to enhance local head differentials. Hydraulic data were also used to provide new insights on the style and scale of geologic heterogeneity known to influence permeability within ice-marginal sediments; this is especially relevant at the study site where fine-scale bedding (millimeters to tens of centimeters scale) and lateral continuity of units (meters to hundreds of meters scale) influence water recharge and dense nonaqueous phase liquids migration and distribution.

This study evaluates the utility of ambient temperature profiles collected in sealed bedrock boreholes to assess variability in groundwater flow in discretely fractured shallow bedrock environments. A conceptual model for groundwater flow and groundwater-surface water temperature conditions and their interaction in a temperate climate is developed through a statistical interpretation of time-lapse thermal deviation logs. Temperature profiles were collected in three angled and three vertical boreholes drilled to 24–32 mbgs (meters below ground surface) and temporarily sealed with an impermeable fabric liner in a fractured dolostone bedrock aquifer adjacent to and extending beneath a bedrock river to monitor seasonal hydrodynamics. Ambient borehole temperature profiles collected every 1–8 weeks over a 12 month period identified zones of hydraulic activity during periods of intra-seasonal stability without the interference of open borehole cross-connection. Signal cross-correlation and Fourier spectra analysis of thermal deviation logs provided a novel way to observe the shallow bedrock flow system’s temperature evolution due to advection along discrete fractures in response to seasonal transience, and to identify and isolate noise caused by free-convection cells within the sealed borehole. This approach represents a diagnostic tool that improves confidence in identifying depth discrete, hydraulically active fracture zones from thermal deviation data sets in a shallow, fractured sedimentary bedrock environment. Variably scaled free-convection cells were observed within the borehole water columns during the colder winter periods. Although these periods were accompanied by higher signal noise near the river/atmospheric interface, these cells led to a temporary thermal disequilibrium between the borehole water column and formation water deeper in the bedrock. These conditions increased the maximum depth of thermal detections associated with discrete groundwater flow features from 14 mbgs in the summer to 26 mbgs in the winter, thereby enhancing the understanding of shallow groundwater flow systems under the direct influence of surface water.

Transitional age youth (TAY) encounter many challenges as they navigate a developmental period marked by milestones that revolve around formation of identity, independence, and formation of relationships. The ability to successfully traverse this transition can be significantly affected by a mood disorder. Development of a mood disorder during this time period puts TAY at high risk for adverse adult outcomes as related to education, employment, health, and social functioning. TAY with early onset of bipolar disorder or major depressive disorder (MDD) have a more complex course of illness when compared to their adult onset counterparts. Using a case example, this chapter discusses specific challenges faced by transitional age youth with mood disorders, guidance on diagnostic clarification, and suggestions for treatment and management. Discussion of treatment planning incorporates the assessment of a TAY’s readiness to individuate, pharmacological and psychotherapy interventions, and the effective use of systems (i.e., school, family, occupational, health care) to support a youth in becoming an adult while managing a mood disorder.

OBJECTIVES: Hospitals accredited by The Joint Commission (TJC) are now required to use a validated screening tool and a standardized method for assessment of suicide risk in all behavioral health patients. Our aims for this study were (1) to implement a TJC-compliant process of suicide risk screening and assessment in the pediatric emergency department (ED) and outpatient behavioral health clinic in a large tertiary care children’s hospital, (2) to describe characteristics of this population related to suicide risk, and (3) to report the impact of this new process on ED length of stay (LOS). METHODS: A workflow using the Columbia Suicide Severity Rating Scale was developed and implemented. Monthly reviews of compliance with screening and assessment were conducted. Descriptive statistics were used to define the study population, and multivariable regression was used to model factors associated with high suicide risk and discharge from the ED. ED LOS of behavioral health patients was compared before and after implementation. RESULTS: Average compliance rates for screening was 83% in the ED and 65% in the outpatient clinics. Compliance with standardized assessments in the ED went from 0% before implementation to 88% after implementation. The analysis revealed that 72% of behavioral health patients in the ED and 18% of patients in behavioral health outpatient clinics had a positive suicide risk. ED LOS did not increase. The majority of patients screening at risk was discharged from the hospital after assessment. CONCLUSIONS: A TJC-compliant process for suicide risk screening and assessment was implemented in the ED and outpatient behavioral health clinic for behavioral health patients without increasing ED LOS.

A complex mixture of dissolved organic contaminants, emanating from a many decades-old, residual, dense non-aqueous phase liquid (DNAPL) source, migrates through unconfined, moderately heterogeneous, glacial-derived sediments and sedimentary rock in a residential area of Dane County, Wisconsin, USA. A portion of this contaminant plume intersects a large man-made pond, roughly 400 m downgradient of the source zone. Depth-discrete, multilevel groundwater sampling, detailed sedimentological logs, and hydraulic head profiles were used to delineate the spatial distribution of hydraulic, geologic, organic contaminant, and redox hydrochemical conditions within the established plume along two transects immediately upgradient of the pond. Twenty-one contaminants were detected and classified into four major contaminant groups: chlorinated ethenes, chlorinated ethanes, aromatics (BTEX: benzene, toluene, ethylbenzene, xylene), and aliphatic ketones. Within the glacial sediments and shallow bedrock, zones of reductive dechlorination of chlorinated ethenes and ethanes were juxtaposed with zones of BTEX and ketone degradation. Spatial heterogeneity in the concentration and distribution of contaminant groups and redox conditions was observed over lateral distances of tens of meters and vertical distances of tens of centimeters along the two transects. Although the site was situated in a complex glacial depositional environment, lithologic and hydraulic heterogeneity surprisingly only had a modest influence on the spatial distribution of plume contaminants. Depth-discrete sampling along paired, closely spaced transects (~20 m apart) was essential to assess internal plume composition/concentration evolution along flow paths with strong attenuation over short migration distances. This study shows how paired, highly resolved transects can enhance understanding of transverse and longitudinal variability in areas where contaminant-induced redox conditions control reaction zones and strong plume attenuation.

We provide detailed rearing methods and describe green sunfish (Lepomis cyanellus) gonadal development and histological differentiation for both sexes. Developing in-depth aquaculture protocols and describing the gonadal differentiation of green sunfish could facilitate strategies to control nuisance populations, enhance stocking programs, and provide information for this species' use in bioassay trials or toxicology studies. Our methods resulted in consistent year-round production of green sunfish and allowed us to identify the timing of their gonadal differentiation through histological assessment. Our spawning methods provided year-round volitional spawns from green sunfish broodstock. Our rearing methods involved weaning larval green sunfish off live nauplii and onto only artificial diets by 37 days post-hatch (dph). Most of the offspring generation reached sexual maturity by 213 dph. Green sunfish are gonochoristic, with testes and ovaries differentiating directly from undifferentiated gonads. Ovaries begin to differentiate by 39 dph and testes begin to differentiate by 69 dph. This information can provide biologists consistent means to produce this Centrachid and understand their gonadal development.

Fugitive methane (CH 4 ) leakage associated with conventional and unconventional petroleum development (e.g., shale gas) may pose significant risks to shallow groundwater. While the potential threat of stray (CH 4 ) gas in aquifers has been acknowledged, few studies have examined the nature of its migration and fate in a shallow groundwater flow system. This study examines the geophysical responses observed from surface during a 72 day field-scale simulated CH 4 leak in an unconfined sandy aquifer at Canadian Forces Base Borden, Canada, to better understand the transient behaviour of fugitive CH 4 gas in the subsurface. Time-lapse ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) were used to monitor the distribution and migration of the gas-phase and assess any impacts to groundwater hydrochemistry. Geophysical measurements captured the transient formation of a CH 4 gas plume emanating from the injector, which was accompanied by an increase in total dissolved gas pressure (P TDG ). Subsequent reductions in P TDG were accompanied by reduced bulk resistivity around the injector along with an increase in the GPR reflectivity along horizontal bedding reflectors farther downgradient. Repeat temporal GPR reflection profiling identified three events with major peaks in reflectivity, interpreted to represent episodic lateral CH 4 gas release events into the aquifer. Here, a gradual increase in P TDG near the injector caused a sudden lateral breakthrough of gas in the direction of groundwater flow, causing free-phase CH 4 to migrate much farther than anticipated based on groundwater advection. CH 4 accumulated along subtle permeability boundaries demarcated by grain-scale bedding within the aquifer characteristic of numerous Borden-aquifer multi-phase flow experiments. Diminishing reflectivity over a period of days to weeks suggests buoyancy-driven migration to the vadose zone and/or CH 4 dissolution into groundwater. Lateral and vertical CH 4 migration was primarily governed by subtle, yet measurable heterogeneity and anisotropy in the aquifer.

Organic solvent (i.e., dense nonaqueous phase liquid, DNAPL) migration in the subsurface is known to be extremely sensitive to geologic heterogeneity. There is often a focus on heterogeneity that results from changing depositional conditions over short spatial scales. Similar or even more extreme spatial heterogeneity can result postdeposition due to erosional processes. This study applies a synergistic approach based on a combination of high-resolution lithologic logs of continuous cores, borehole geophysical logs, surface electrical resistivity, and seismic refraction tomography models to assess spatial heterogeneity in a shallow bedrock sequence subject to multiple unconformities and contaminated with a mixture of organic chemicals. The persistence of DNAPL in the source zone and an associated dissolved-phase plume led to variable impacts on formation resistivity across the study site. Seismic refraction in combination with electrical resistivity tomography improved interpretation of highly irregular erosional boundaries by delineating sharp lateral transitions in lithologic composition near the source zone and across the dissolved-phase plume. Electrical resistivity was effective at differentiating between clean and mud-rich sandstones and their unconformable contact with an underlying dolostone. Geophysical measurements revealed eroded dolostone mounds encased by a network of younger mud-rich sandstones channelized by clean semi-lithified sand, all of which was buried beneath variable glacial drift. Our synergistic multidimensional approach resulted in the development of a detailed three-dimensional shallow bedrock geospatial model, which has led to an improved understanding of DNAPL migration and contaminant plume heterogeneity.

Expansion of shale gas extraction has fuelled global concern about the potential impact of fugitive methane on groundwater and climate. Although methane leakage from wells is well documented, the consequences on groundwater remain sparsely studied and are thought by some to be minor. Here we present the results of a 72-day methane gas injection experiment into a shallow, flat-lying sand aquifer. In our experiment, although a significant fraction of methane vented to the atmosphere, an equal portion remained in the groundwater. We find that methane migration in the aquifer was governed by subtle grain-scale bedding that impeded buoyant free-phase gas flow and led to episodic releases of free-phase gas. The result was lateral migration of gas beyond that expected by groundwater advection alone. Methane persisted in the groundwater zone despite active growth of methanotrophic bacteria, although much of the methane that vented into the vadose zone was oxidized. Our findings demonstrate that even small-volume releases of methane gas can cause extensive and persistent free phase and solute plumes emanating from leaks that are detectable only by contaminant hydrogeology monitoring at high resolution. Most monitoring of methane well leakage focuses on emissions of methane gas to the atmosphere. In a controlled-release field experiment, significant methane also persisted in aquifer groundwater due to lateral migration along bedding planes.

This study involves a regional-scale evaluation of a frequency-domain airborne electromagnetic survey within a bedrock-groundwater-dependent region currently undergoing a water budget and water stress assessment. Geophysical data is evaluated through a comparison of airborne magnetic and electrical resistivity response with a three-dimension regional lithostratigraphic model based on high-quality borehole records.

This study examines potential structural controls on a local Quaternary-bedrock groundwater flow system through an integrated analysis of frequency-domain airborne electromagnetic data together with ground-based seismic refraction, electrical resistivity and gravity data. Datasets are compared across two transect over a buried bedrock valley to better understand regional groundwater flow paths.

Major foodborne bacterial pathogens, such as Campylobacter jejuni, have devised complex strategies to establish and foster intestinal infections. For more than two decades, researchers have used immortalized cell lines derived from human intestinal tissue to dissect C. jejuni-host cell interactions. Known from these studies is that C. jejuni virulence is multifactorial, requiring a coordinated response to produce virulence factors that facilitate host cell interactions. This study was initiated to identify C. jejuni proteins that contribute to adaptation to the host cell environment and cellular invasion. We demonstrated that C. jejuni responds to INT 407 and Caco-2 cells in a similar fashion at the cellular and molecular levels. Active protein synthesis was found to be required for C. jejuni to maximally invade these host cells. Proteomic and transcriptomic approaches were then used to define the protein and gene expression profiles of C. jejuni co-cultured with cells. By focusing on those genes showing increased expression by C. jejuni when co-cultured with epithelial cells, we discovered that C. jejuni quickly adapts to co-culture with epithelial cells by synthesizing gene products that enable it to acquire specific amino acids for growth, scavenge for inorganic molecules including iron, resist reactive oxygen/nitrogen species, and promote host cell interactions. Based on these findings, we selected a subset of the genes involved in chemotaxis and the regulation of flagellar assembly and generated C. jejuni deletion mutants for phenotypic analysis. Binding and internalization assays revealed significant differences in the interaction of C. jejuni chemotaxis and flagellar regulatory mutants. The identification of genes involved in C. jejuni adaptation to culture with host cells provides new insights into the infection process.

Subsurface leakage of natural gas from petroleum wells can impact freshwater aquifers. Accurate prediction of gas migration in the subsurface will depend on knowledge of permeability, porosity, and flow system conditions. A series of two-dimensional numerical multi-phase flow simulations (CFbio) were conducted to investigate the role of multi-phase parameters (relative permeability and air entry pressure), flow system conditions (intrinsic permeability, anisotropy, and groundwater velocity), and geometric properties (layer thickness and layer lateral continuity) on the flow of gas-phase methane emanating from two variable-rate point sources in an unconfined sandy aquifer. Numerical simulations showed that for a homogeneous, weakly anisotropic aquifer, gas migrates almost exclusively vertically due to buoyancy, before venting to the vadose zone and atmosphere. As vertical migration became restricted through increased anisotropy, inclusion of lower-permeable layers, or increased horizontal groundwater velocity, an increase in the lateral component of gas migration was observed. This led to the formation of a broader lateral migration of the gas-phase plume and establishment of variably distributed vertical preferential flow paths, ultimately resulting in increased gas retention in the aquifer with relatively less methane reaching the vadose zone or atmosphere. The inclusion of a thin layer with moderately lower permeability (1-2 orders of magnitude) and increased air entry pressure was used to depict a fine-grained sand lens within a uniform aquifer. This subtle feature led to the formation of thin gas pools extending up- and down-gradient beneath the lens, allowing methane to travel much farther and faster than by groundwater advection alone, which is consistent with field observations during the experiment. In all scenarios investigated gas-phase methane was shown to migrate predominantly vertically due to buoyancy, until the aquitard permeability was

Fractured sedimentary bedrock rivers exhibit complicated flow patterns controlled by the geometry, extent and connectivity of fractures and dissolution-enhanced conduits. In a bedrock river environment these features variably connect surface water to groundwater. Given the nature of discrete fracture and conduit networks, these flow systems can be anisotropic and heterogeneous over a wide range of scales. Portable and non-invasive geophysical methods are ideal for the initial characterization of shallow hydrogeologic systems in ecologically sensitive environments. Here, we evaluate the utility of the electromagnetic (EM) azimuthal resistivity method for characterizing shallow vertical and subvertical fracture set orientations in the presence of localized dissolution-enhanced features near a sedimentary bedrock river located in Southern Ontario, Canada. Multiple EM coil spacings ranging from 1 to 10 m in vertical and horizontal dipole modes were applied at two locations within a 10 × 25 m study plot; azimuthal rotations were conducted using symmetric and asymmetric geometries. The observed anisotropic response was evaluated using 100 MHz ground-penetrating radar (GPR) measurements collected across the study plot area. A joint analysis of EM and GPR data revealed that fracture-based anisotropy can be identified in the presence of local heterogeneities (i.e., dissolution-enhanced features) at scales considerably smaller than those of previous studies. These non-invasive geophysical data sets can be used to optimize the design of multi-borehole groundwater monitoring stations along bedrock river channels, such that angled boreholes could be emplaced and orientated to intercept major fracture networks and local dissolution features. These data could also improve 3-D fracture network conceptualizations utilizing discrete information from angled and vertical boreholes.

Summary Bedrock rivers exhibit very different hydraulic and ecological regimes compared to alluvial rivers. Groundwater–surface water interaction in rivers that flow directly on sedimentary bedrock surfaces with exposed fracture and conduit networks is generally based on alluvial river conceptual models. However, the dual and triple porosity systems of sedimentary rock (e.g., matrix, fractures and vugs) leads to highly variable hydraulic pathways and groundwater velocities that, in turn, result in processes that are very different than those derived from alluvial concepts. Relative to alluvial rivers there has been very little direct examination of dynamic interactions, such as fluxes, groundwater velocities, and mechanisms affecting water quality across the channel interface; this is largely because bedrock rivers are difficult to instrument and monitor given their heterogeneous and anisotropic flow systems. In this study, we evaluate the capacity of non-invasive, low impact ground-penetrating radar and frequency-domain electromagnetic induction methods capable of detecting discrete fracture and conduit features, mapping complex distributions of lithostratigraphic interfaces, and providing information about formation properties along a partially exposed section of the Eramosa River located in Ontario, Canada. Geophysical data are supported by direct hydrogeologic and geologic information obtained from a nearby borehole piezometer cluster and a continuous 15 m rock core. Valuable insights were gained into the lateral extent and geometry of structurally-controlled whydrostratigraphic units (e.g., dissolution-enhanced fractures, epikarst and karst features), which are expected to strongly influence groundwater and surface water interaction along the channel. An integrated application of GPR and EMI methods was necessary to fully understand the complex geometry of geologic boundaries and karst features within the shallow bedrock aquifer. The identification of epikarst below fluvial sediment and its relationship to the formation of dissolution features, exposed fracture conduit networks and sinkholes represents the basis for understanding the dynamic hydraulic responses between the surface water and the shallow bedrock aquifer.

Heterogeneous semiconductors are underexploited as photoredox catalysts in organic synthesis relative to their homogeneous, molecular counterparts. Here, we report the use of metal/TiO2 particles as catalysts for light-induced dehydrogenative imine transformations. The highly oxophilic nature of the TiO2 surface promotes the selective binding and dehydrogenation of alcohols in the presence of other oxidizable and Lewis basic functional groups. This feature enables the clean photogeneration of aldehyde equivalents that can be utilized in multicomponent couplings.

Bedrock rivers occur where surface water flows along an exposed rock surface. Fractured sedimentary bedrock can exhibit variable groundwater residence times, anisotropic flow paths, heterogeneity, along with diffusive exchange between fractures and rock matrix. These properties of the rock will affect thermal transients in the riverbed and groundwater–surface water exchange. In this study, surface electrical methods were used as a non-invasive technique to assess the scale and temporal variability of riverbed temperature and groundwater–surface water exchange beneath a sedimentary bedrock riverbed. Conditions were monitored on a semi-daily to semi-weekly interval over a full annual period that included a seasonal freeze-thaw cycle. Surface electromagnetic induction and electrical resistivity imaging methods captured conditions beneath the riverbed along a pool-riffle sequence within the Eramosa River, Guelph, Ontario, Canada. Geophysical datasets were accompanied by continuous measurements of aqueous specific conductance, temperature and river stage. Vertical temperature profiling conducted in an inclined borehole underlying the river revealed active groundwater flow zones through fracture networks within the upper 10 m of rock. Resistivity measurements during cooler high-flow and warmer low-flow conditions identified a spatiotemporal riverbed response that was largely dependent upon riverbed morphology and groundwater temperature. Time-lapse resistivity profiles collected across the pool and riffle identified seasonal transients within the upper 2 m and 3 m of rock, respectively, with spatial variations controlled by riverbed morphology (pool verses riffle) and dominant surficial rock properties (competent verses weathered rock rubble surface). While the pool and riffle both exhibited a dynamic resistivity through seasonal cooling and warming cycles, conditions beneath the pool were more dynamic, largely due to the formation of river ice. Although seasonal resistivity trends beneath the riverbed suggest groundwater discharge may be influencing the spatiotemporal extent of a groundwater-surface water mixing zone, intraseasonal resistivity transience suggest potential groundwater–surface water exchange across the upper few meters of rock.

[1] A major challenge in vadose zone hydrology is to obtain accurate information on the temporal changes of the vertical soil water distribution and its feedback with the atmosphere and groundwater. A state of the art coupled hydrogeophysical inversion scheme is applied to evaluate soil hydraulic properties of a synthetic model and a field soil in southern Ontario based on time-lapse monitoring of soil dynamics with surface ground-penetrating radar (GPR). Film flow was included in the hydrological model to account for noncapillary water flow in a sandy medium during dry conditions. The synthetic study illustrated that GPR data contain sufficient information to accurately constrain soil hydraulic parameters within a coupled inversion framework and led to an accurate estimation of the soil hydraulic properties. When film flow was not accounted for within the inversion, an equally good fit could still be achieved. In this case, errors introduced by neglecting film flow were compensated by different hydraulic parameters. For the field data, the coupled inversion reduced the overall misfit compared to an uncalibrated model using hydraulic parameters obtained from laboratory data. Although the data fit improved significantly for water content in the deeper soil layers, accounting for film flow in the uppermost subsurface layer did not lead to a better fit of the GPR data. Further research is needed to describe the processes controlling water content in the dry range, in particular coupled heat and vapor transport. This study illustrates the suitability of surface GPR measurements combined with coupled inversion for near-surface characterization of soil hydraulic parameters.

In many hydrological applications, ground-wave velocity measurements are increasingly used to map and monitor shallow soil water content. In this study, we propose an automated spectral velocity analysis method to determine the direct ground-wave (DGW) velocity from common midpoint (CMP) or multi-offset ground-penetrating radar (GPR) data. The method introduced in this paper is a variation of the well-known spectral velocity analysis for seismic and GPR reflection events where velocity spectra are computed using different coherency measures along hyperbolas following the normal moveout model. Here, the unnormalized cross-correlation is computed between waveforms across data gathers that are corrected with a linear moveout equation using a predefined range of velocities. Peaks in the resulting velocity spectra identify linear events in the GPR data gathers like DGW events and allow for estimating the corresponding velocities. In addition to obtaining a DGW velocity measurement, we propose a robust method to estimate the associated velocity uncertainties based on the width of the peak in the calculated velocity spectrum. Our proposed method is tested on synthetic data examples to evaluate the influence of subsurface velocity, surveying geometry and signal frequency on the accuracy of estimated ground-wave velocities. In addition, we investigate the influence of such velocity uncertainties on subsequent soil water content estimates using an established petrophysical relationship. Furthermore, we apply our approach to analyse field data, which were collected across a test site in Canada to monitor a wide range of seasonal soil moisture variations. A comparison between our spectral velocity estimates and results derived from manually picked ground-wave arrivals shows good agreement, which illustrates that our spectral velocity analysis is a feasible tool to analyse DGW arrivals in multi-offset GPR data gathers in an objective and more automated manner.

Summary Soil moisture measurement techniques are of utmost importance to vadose zone hydrologists. Surface hydrogeophysical methods, such as ground-penetrating radar (GPR), have the capacity to provide field-scale soil moisture information across a range of depth scales. This paper presents an extensive field study using multi-frequency (i.e., 225 MHz, 450 MHz, 900 MHz) GPR common-midpoint (CMP) soundings to monitor a complete annual cycle of soil moisture conditions at three distinct sites. We examine the use of normal-moveout (NMO) velocity analysis applied to CMP data for monitoring highly dynamic vertical soil moisture conditions in a mid-latitude climate consisting of wetting/drying and freeze/thaw cycles with varying degrees of magnitude and vertical velocity gradient. NMO velocity analysis is used to construct interval-velocity-depth models at a fixed location collected every 1–4 weeks. These time-lapse models are combined to construct temporal interval-velocity fields, which are converted into soil moisture content using an appropriate petrophysical relationship. Using these moisture fields, we were able to characterize the vertical distribution and dynamics of soil moisture in the shallow vadose zone. Although the use of multiple antenna frequencies provided varying investigation depths and vertical resolving capabilities, optimal characterization of soil moisture conditions was obtained with high-frequency 900 MHz antennas. The integration of direct ground wave and NMO velocity data from a single CMP sounding allowed us to better refine the shallow soil moisture profile and underlying vadose zone conditions during seasonal wetting, drying and freezing cycles. This study demonstrates the capacity of GPR to characterize vertical moisture dynamics, and highlights the importance of collecting high-resolution data along the air–soil interface to resolve the water content profile from the surface down to the deeper vadose zone conditions.

Soil water content measurement using ground-penetrating radar (GPR) requires an appropriate petrophysical relationship between the dielectric permittivity and volumetric water content of the soil. The suitability of different relationships for GPR soil water content estimation has not been thoroughly investigated under natural field conditions for a complete range of seasonal soil conditions. In this study, we examined the ability of various empirical relationships, volumetric mixing formulae, and effective medium approximations to predict near-surface volumetric soil water content using high-frequency direct ground wave (DGW) velocity measurements for three soil textures. The estimated water contents were compared with values obtained from gravimetric sampling. The accuracy of soil water content predictions obtained from the various relationships ranged considerably. The best predictions for the overall data set in terms of RMSE were obtained with a differential effective medium approximation based on a coated sphere model (RMSE = 0.045 m3 m−3); however, an empirical relationship (RMSE = 0.052 m3 m−3) and a volumetric mixing formula (RMSE = 0.048 m3 m−3) also performed well. These best-fitting relationships do exhibit some degree of textural bias that should be considered in the choice of petrophysical relationship for a given data set. Further improvements in water content estimates were obtained using our best-fit third-order polynomial relationship (RMSE = 0.041 m3 m−3) and our three-phase volumetric mixing formula with geometric parameter α = 0.36 (RMSE = 0.042 m3 m−3); these optimized relationships were developed using the DGW permittivity and soil water content data collected in this study.

High frequency ground-penetrating radar direct ground waves were used to monitor the seasonal development of a thin, high velocity frozen soil layer over a wet low velocity unfrozen substratum. During the freezing process, the progressive attenuation of a low velocity direct ground wave and the subsequent development of a high velocity direct ground wave were observed. Numerical simulations showed that low velocity direct wave event occurring after freezing commences is due to energy leaking across the frozen layer from the spherical body wave in the unfrozen half space. This leaky phase progressively dissipates until the frozen layer reaches a thickness equivalent to one quarter of the dominant wavelength in the frozen ground. The appearance of the high velocity direct wave is governed by its destructive interference with the reflection events from the base of the frozen layer. This interference obscures the high velocity direct wave event until the frozen layer thickness reached one half of the dominant wavelength in the frozen ground. These changes in direct wave transmission permit frozen layer monitoring for thicknesses that are significantly less than those feasible using the reflection event from the frozen–unfrozen boundary.

[1] Surface ground-penetrating radar (GPR) techniques have been used by a number of previous researchers to characterize soil moisture content in the vadose zone. However, limited temporal sampling and low resolution near the surface in these studies greatly impedes the quantitative analysis of vertical soil moisture distribution and its associated dynamics within the shallow subsurface. To further examine the capacity of surface GPR, we have undertaken an extensive 26 month field study using concurrent high-frequency (i.e., 900 MHz) reflection profiling and common-midpoint (CMP) soundings to quantitatively monitor soil moisture distribution and dynamics within the shallow vadose zone. This unprecedented data set allowed us to assess the concurrent use of these techniques over two contrasting annual cycles of soil conditions. Reflection profiles provided high-resolution traveltime data between four stratigraphic reflection events while cumulative results of the CMP sounding data set produced precise depth estimates for those reflecting interfaces, which were used to convert interval-traveltime data into soil moisture. The downward propagation of major infiltration episodes associated with seasonal and transient events are well resolved by the GPR data. The use of CMP soundings permitted the determination of direct ground wave velocities, which provided high-resolution information along the air-soil interface. This improved resolution enabled better characterization of short-duration wetting/drying and freezing/thawing processes, and permitted better evaluation of the nature of the coupling between shallow and deep moisture conditions. The nature of transient infiltration pulses, evapotranspiration episodes, and deep drainage patterns observed in the GPR data series were further examined by comparing them with a vertical soil moisture flow simulation based on the variably saturated model, HYDRUS-1D. Using laboratory-derived soil hydraulic property information from soil samples and a number of simplifying assumptions about the upper and lower-boundary condition, we were able to achieve very good agreement between measured and simulated soil moisture profiles without model calibration; this is a strong indication of the overall quality of the GPR-derived soil moisture estimates. The only notable difference between simulated values and GPR water content estimates occurred during extended dry soil conditions near the surface.

In this study we present 3T and 3T1D DRAM cells designed using FinFET technology. Overall, the 3T DRAM cell has a 43.6% faster write speed than the 3T1D cell and uses less dynamic current (30.4% less write current and 14.6% less read current). The FinFET 3T1D DRAM cell offers a 16.7% faster read speed and 48.6% less read leakage current than the 3T1D cell. The 3T DRAM cell offers less variation in delays, up to 37% less than the 3T1D cell for write delay, due to parameter corner simulations. Overall for a system, the 3T FinFET DRAM cell is more promising due to its low dynamic current and significantly shorter write speed which leads to a smaller maximum delay.

Purpose: Chronic lymphocytic leukemia (CLL), a malignancy of mature B cells, is incurable with chemotherapy. Signals from the microenvironment support leukemic cell survival and proliferation and may confer chemotherapy resistance. ON 01910.Na (Rigosertib), a multikinase phosphoinositide 3-kinase (PI3K) inhibitor, is entering phase III trials for myelodysplastic syndrome. Our aim was to analyze the efficacy of ON 01910.Na against CLL cells in vitro and investigate the molecular effects of this drug on tumor biology. Experimental Design: Cytotoxicity of ON 01910.Na against CLL cells from 34 patients was determined in vitro with flow cytometry of cells stained with Annexin V and CD19. Global gene expression profiling on Affymetrix microarrays, flow cytometry, Western blotting, and cocultures with stroma cells were used to delineate ON 01910.Na mechanism of action. Results: ON 01910.Na induced apoptosis in CLL B cells without significant toxicity against T cells or normal B cells. ON 01910.Na was equally active against leukemic cells associated with a more aggressive disease course [immunoglobulin heavy-chain variable region unmutated, adverse cytogenetics] than against cells without these features. Gene expression profiling revealed two main mechanisms of action: PI3K/AKT inhibition and induction of ROS that resulted in an oxidative stress response through activating protein 1 (AP-1), c-jun-NH2-terminal kinase, and ATF3 culminating in the upregulation of NOXA. ROS scavengers and shRNA mediated knockdown of ATF3- and NOXA-protected cells from drug-induced apoptosis. ON 01910.Na also abrogated the prosurvival effect of follicular dendritic cells on CLL cells and reduced SDF-1–induced migration of leukemic cells. Conclusions: These data support the clinical development of ON 01910.Na in CLL. Clin Cancer Res; 18(7); 1979–91. ©2012 AACR.

This paper presents a multi-year field study in which high-frequency 900 MHz reflection traveltime measurements were used to monitor vertical soil moisture distribution in the upper 3.0 m of vadose zone. GPR reflection profiles and common-midpoint (CMP) soundings were collected over the complete annual cycle of soil conditions characterized by numerous wetting, drying and freezing cycles typical of mid-latitude climates. The presence of four distinct stratigraphic reflection events at well-defined depths permitted quantitative assessment of seasonal moisture processes and their temporal dynamics during the study period. The incorporation of direct ground wave measurements from coincidently collected CMP soundings yielded improved resolution at the air-soil interface which facilitated characterization of the hydraulic coupling between shallow and deeper moisture conditions.