Publications by authors named "William Brewer"

A small wearable camera, SenseCam, passively captured pictures from everyday experience that were later used to evaluate the accuracy and completeness of autobiographical memory. Nine undergraduates wore SenseCams that took pictures every 10 s for two days. After one week and one month, participants first recalled their experiences from specific time periods (timeslices), then reviewed the corresponding pictures to make corrections and report information omitted from initial recall.

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Unlabelled: Bacteria shape interactions between hosts and fungal pathogens. In some cases, bacteria associated with fungi are essential for pathogen virulence. In other systems, host-associated microbiomes confer resistance against fungal pathogens.

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Background: Insects are an important reservoir of viral biodiversity, but the vast majority of viruses associated with insects have not been discovered. Recent studies have employed high-throughput RNA sequencing, which has led to rapid advances in our understanding of insect viral diversity. However, insect genomes frequently contain transcribed endogenous viral elements (EVEs) with significant homology to exogenous viruses, complicating the use of RNAseq for viral discovery.

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The bacterial lipid membrane, consisting both of fatty acid (acyl) tails and polar head groups, responds to changing conditions through alteration of either the acyl tails and/or head groups. This plasticity is critical for cell survival as it allows maintenance of both the protective nature of the membrane as well as functioning membrane protein complexes. Bacteria that live in fatty-acid rich environments, such as those found in the human host, can exploit host fatty acids to synthesize their own membranes, in turn, altering their physiology.

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is a Gram-positive bacterium that normally exists as an intestinal commensal in humans but is also a leading cause of nosocomial infections. Previous work noted that growth supplementation with serum induced tolerance to membrane-damaging agents, including the antibiotic daptomycin. Specific fatty acids found within serum could independently provide tolerance to daptomycin (protective fatty acids), yet some fatty acids found in serum did not and had negative effects on enterococcal physiology (nonprotective fatty acids).

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Bacterial membranes are complex mixtures with dispersity that is dynamic over scales of both space and time. To capture adsorption onto and transport within these mixtures, we conduct simultaneous second harmonic generation (SHG) and two-photon fluorescence measurements on two different gram-positive bacterial species as the cells uptake membrane-specific probe molecules. Our results show that SHG not only can monitor the movement of small molecules across membrane leaflets but also is sensitive to higher-level ordering of the molecules within the membrane.

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Context: Innovative strategies are needed to improve the prevalence of working smoke alarms in homes. To our knowledge, this is the first study to report on the effectiveness of Facebook advertising and automated telephone calls as population-level strategies to encourage an injury prevention behavior.

Objective: We examine the effectiveness of Facebook advertising and automated telephone calls as strategies to enroll individuals in Baltimore City's Fire Department's free smoke alarm installation program.

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is an opportunistic human fungal pathogen that causes life-threatening systemic infections, as well as oral mucosal infections. Phospholipids are crucial for pathogenesis in , as disruption of phosphatidylserine (PS) and phosphatidylethanolamine (PE) biosynthesis within the cytidine diphosphate diacylglycerol (CDP-DAG) pathway causes avirulence in a mouse model of systemic infection. The synthesis of PE by this pathway plays a crucial role in virulence, but it was unknown if downstream conversion of PE to phosphatidylcholine (PC) is required for pathogenicity.

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An analytical procedure for the analysis of 10 β-adrenergic agonists (cimaterol, terbutaline, salbutamol, isoxsuprine, ractopamine, cimbuterol, clenbuterol, brombuterol, mabuterol and mapenterol) in pork meat was developed and validated using LC-MS/MS. An automated dispersive pipette extraction (DPX) was employed on a Hamilton Microlab® NIMBUS96® platform to extract the analytes of interest prior to LC-MS/MS analysis. The extraction time was <20 min with a total LC-MS/MS run time of 9.

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This Letter reports on the unusual diffusion behavior of Ge during oxidation of a multilayer Si/SiGe fin. It is observed that oxidation surprisingly results in the formation of vertically stacked Si nanowires encapsulated in defect free epitaxial strained SiGe. High angle annular dark field scanning transmission electron microscopy (HAADF-STEM) shows that extremely enhanced diffusion of Ge occurs along the vertical Si/SiO oxidizing interface and is responsible for the encapsulation process.

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A collaborative study was conducted to investigate discrepancies in recoveries of two commonly prescribed compounds, amitriptyline and cyclobenzaprine, in patient urine samples when hydrolyzed with different enzymes from different sources. A 2- to 10-fold increase in analyte recoveries was seen for patient samples hydrolyzed using a recombinant β-glucuronidase (IMCSzyme™) over samples hydrolyzed with β-glucuronidase from Haliotis rufescens We report outcomes from four commercially available β-glucuronidase enzymes (IMCSzyme™, Patella vulgata, Helix pomatia and H. rufescens) on patient samples that tested positive for amitriptyline and cyclobenzaprine.

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This paper reports the development of an automated method of QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) using pipet tips fitted with filtration screens and containing primary-secondary amine, magnesium sulfate, and graphitized carbon black. These tips are referred to as "QuEChERS Tips". Using loosely contained sorbent, dispersive solid phase extraction (dSPE) cleanup was performed with the QuEChERS Tips and automation.

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Emerging "life-logging" technologies have tremendous potential to augment human autobiographical memory by recording and processing vast amounts of information from an individual's experiences. In this experiment undergraduate participants wore a SenseCam, a small, sensor-equipped digital camera, as they went about their normal daily activities for five consecutive days. Pictures were captured either at fixed intervals or as triggered by SenseCam's sensors.

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Simple and rapid methods for the analysis of pesticides in produce samples have been developed. The current study involves analysis of nonpolar and polar pesticides using GC-ECD and GC-NPD, respectively. The nonpolar pesticides were extracted using disposable pipette extraction (DPX) following a preliminary acetone extraction based on the Luke method.

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Organochlorine, organophosphate pesticides and fungicides in fruits and vegetables were analyzed using disposable pipette extraction (DPX) followed by gas chromatography-mass spectrometry-selective ion monitoring (GC/MS-SIM). The intrinsic rapid mixing capabilities of DPX result in fast and efficient extractions, and eluates are concentrated by using minimal elution solvent volumes rather than solvent evaporation methods. Matrix-matched calibrations were performed with reversed phase mechanisms (DPX-RP), and the limits of detection (LOD) were determined to be lower than 0.

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Organochlorine and organophosphate pesticides in corn muffin mix and cocoa beans were analyzed using disposable pipette extraction (DPX) for rapid cleanup followed by gas chromatography-mass spectrometry (GC-MS). The DPX method in this study used weak anion exchange (WAX) mechanisms to remove the major sample matrix interferences, fatty acids, from the chromatographic analyses. The limits of detection (LOD) were determined to be <10 ppb for all studied pesticides in corn muffin.

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The extraction of basic, acidic, and neutral drugs of abuse from a low volume of urine (0.2 mL) using disposable pipette extraction (DPX) is described. DPX is a solid-phase extraction device that uses loosely contained sorbent inside a pipette tip fitted with a screen.

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The present experiment tested the hypothesis that unconscious reconstructive memory processing can lead to the breakdown of the relationship between memory confidence and memory accuracy. Participants heard deceptive schema-inference sentences and nondeceptive sentences and were tested with either simple or forced-choice recognition. The nondeceptive items showed a positive relation between confidence and accuracy in both simple and forced-choice recognition.

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The Ozone Profiling Atmospheric Lidar is a scanning four-wavelength ultraviolet differential absorption lidar that measures tropospheric ozone and aerosols. Derived profiles from the lidar data include ozone concentration, aerosol extinction, and calibrated aerosol backscatter. Aerosol calibrations assume a clear air region aloft.

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Essential to forensic laboratories is the desire to find a more sensitive, rapid method of analyzing Delta9-tetrahydrocannabinol (THC) and metabolite in biological specimens. Disposable pipette extraction (DPX) is a valuable method in extracting THC and 11-nor-Delta9-tetrahydrocannabinol-9-carboxylic acid (THCc) in blood and THCc in urine. Less waste and solvent usage; smaller specimen volume; clean chromatograms; and utilization of lowcost equipment and consumables were achieved using this method.

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We propose that memory confidence is based on the processes and products of the just-completed memory task, along with the participants' metamemory beliefs about the relation of these processes and products to memory accuracy. We tested this metamemory approach to confidence by having participants carry out a simple recognition memory task with deceptive and nondeceptive items. The deceptive items were sentences that contained a possible synonym substitution, thus allowing errors based on gist memory.

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We compared clinical characteristics and outcomes for dogs with various digital tumors. Medical records and histology specimens of affected dogs from 9 veterinary institutions were reviewed. Risk factors examined included age, weight, sex, tumor site (hindlimb or forelimb), local tumor (T) stage, metastases, tumor type, and treatment modality.

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Purpose: The immunotoxin BR96 sFv-PE40 is an effective antitumor agent against human breast and lung carcinoma xenografts in rodents. This study was designed to (a) determine the frequency with which canine carcinoma cells express Lewis(y) (Le(y)) antigen, thereby identifying canine carcinoma types suitable for the clinical evaluation of BR96 sFv-PE40, and (b) determine the safety and efficacy of BR96 sFv-PE40 in a canine model of spontaneously occurring cancers for investigation of targeted therapy.

Experimental Design: Carcinoma tissue samples were obtained from client-owned dogs presented for medical care.

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