Development of FPGA-based multi-sensor excitation low voltage (MSELV) chassis at Jefferson Lab.

The design and development of the sensor excitation and read back chassis was driven by the requirements for the monitoring and control of two conduction-cooled superconducting magnets in Hall B for the 12 GeV accelerator upgrade. The torus and solenoid superconducting magnets require extensive instrumentation. Sensor selection was accomplished by applying Jefferson Lab's (JLab) risk mitigation process, which employed a failure modes and effects analysis approach. The goal was to accommodate all sensor types for monitoring and control and to develop a generic multisensor excitation low voltage chassis that would be used across both magnet systems with a reduced set of functions. The chassis has been deployed in experimental Hall B at JLab and has been performing successfully since July 2016.

Altered attention and prefrontal cortex gene expression in rats after binge-like exposure to cocaine during adolescence.

Illicit use of drugs frequently begins and escalates during adolescence, with long-term adverse consequences. Because it is increasingly accepted that neural development continues through adolescence, addiction research has become more invested in understanding the behavioral and molecular consequences of early exposure to drugs of abuse. In a novel binge administration paradigm designed to model the pattern of human adolescent drug use, we administered ascending doses of cocaine or saline during a 12-d developmental period [postnatal day 35 (P35) to P46] corresponding to human adolescence. During adulthood (P70), rats treated with this regimen displayed increased responsiveness to the stimulant effects of cocaine. Adult rats also displayed abnormally rapid shifts in attention when performing an attentional set-shifting task, which measures the ability to shift attention between stimuli and whose performance requires an intact prefrontal cortex (PFC). Treatment with cocaine during adolescence also caused acute alterations in the expression of genes encoding cell adhesion molecules and transcription factors within the PFC. Furthermore, we observed decreases in histone methylation, which may indicate a role for chromatin remodeling in the observed changes in gene expression patterns. These findings suggest that exposure to cocaine during adolescence has far-reaching molecular and behavioral consequences in the rat PFC that develop over time and endure long after drug administration has ceased.

Successful decolonization of methicillin-resistant Staphylococcus aureus in paediatric patients with cystic fibrosis (CF) using a three-step protocol.

Methicillin-resistant Staphylococcus aureus (MRSA) is recognized as a bacterial pathogen in patients with cystic fibrosis (CF) although its clinical effects can be variable. The aim of this study was to evaluate the efficacy of a three-step decolonization protocol for MRSA (Belfast CF MRSA decolonization protocol). Of the 17 paediatric patients treated during the five years of the study, eight (47%) were successfully decolonized following one five-day course of oral rifampicin and fusidic acid. The success rate increased to 12 (71%) patients after a second five-day oral treatment course in the 11 patients who remained culture positive at the end of the first treatment cycle. In a further four patients, clearance was achieved with a course of intravenous teicoplanin, increasing the decolonization rate to 16 of 17 patients (94%). These results compare favourably with other published studies and show that MRSA decolonization can be successful in a high proportion of paediatric CF patients.

Automated electrotransformation of Escherichia coli on a digital microfluidic platform using bioactivated magnetic beads.

This paper reports on the use of a digital microfluidic platform to perform multiplex automated genetic engineering (MAGE) cycles on droplets containing Escherichia coli cells. Bioactivated magnetic beads were employed for cell binding, washing, and media exchange in the preparation of electrocompetent cells in the electrowetting-on-dieletric (EWoD) platform. On-cartridge electroporation was used to deliver oligonucleotides into the cells. In addition to the optimization of a magnetic bead-based benchtop protocol for generating and transforming electrocompetent E. coli cells, we report on the implementation of this protocol in a fully automated digital microfluidic platform. Bead-based media exchange and electroporation pulse conditions were optimized on benchtop for transformation frequency to provide initial parameters for microfluidic device trials. Benchtop experiments comparing electrotransformation of free and bead-bound cells are presented. Our results suggest that dielectric shielding intrinsic to bead-bound cells significantly reduces electroporation field exposure efficiency. However, high transformation frequency can be maintained in the presence of magnetic beads through the application of more intense electroporation pulses. As a proof of concept, MAGE cycles were successfully performed on a commercial EWoD cartridge using variations of the optimal magnetic bead-based preparation procedure and pulse conditions determined by the benchtop results. Transformation frequencies up to 22% were achieved on benchtop; this frequency was matched within 1% (21%) by MAGE cycles on the microfluidic device. However, typical frequencies on the device remain lower, averaging 9% with a standard deviation of 9%. The presented results demonstrate the potential of digital microfluidics to perform complex and automated genetic engineering protocols.

Electrowetting-based actuation of droplets for integrated microfluidics.

The serviceability of microfluidics-based instrumentation including 'lab-on-a-chip' systems critically depends on control of fluid motion. We are reporting here an alternative approach to microfluidics based upon the micromanipulation of discrete droplets of aqueous electrolyte by electrowetting. Using a simple open structure, consisting of two sets of opposing planar electrodes fabricated on glass substrates, positional and formational control of microdroplets ranging in size from several nanoliters to several microliters has been demonstrated at voltages between 15-100 V. Since there are no permanent channels or structures between the plates, the system is highly flexible and reconfigurable. Droplet transport is rapid and efficient with average velocities exceeding 10 cm s(-1) having been observed. The dependence of the velocity on voltage is roughly independent of the droplet size within certain limits, thus the smallest droplets studied (approximately 3 nl) could be transported over 1000 times their length per second. Formation, mixing, and splitting of microdroplets was also demonstrated using the same microactuator structures. Thus, electrowetting provides a means to achieve high levels of functional integration and flexibility for microfluidic systems.

Liquid chromatographic determination including simultaneous "on-cartridge" separation of ranitidine cisapride drug combinations from paediatric plasma samples using an automated solid-phase extraction procedure.

HPLC methodology was investigated for the simultaneous determination of cisapride and ranitidine in small volume paediatric plasma samples. Such a simultaneous determination proved difficult due to the small sample volumes, the low concentrations of the drugs and the different log P values of the two compounds. The two drugs and their respective internal standards were separated "on-cartridge" using HLB Solid Phase Extraction cartridges and the samples quantified by individual HPLC methodologies. The technique has been applied successfully to 60 paediatric plasma samples containing both cisapride and ranitidine.

Binge cocaine administration in adolescent rats affects amygdalar gene expression patterns and alters anxiety-related behavior in adulthood.

BACKGROUND: Administration of cocaine during adolescence alters neurotransmission and behavioral sensitization in adulthood, but the effect on the acquisition of fear memories and the development of emotion-based neuronal circuits is unknown. METHODS: We examined fear learning and anxiety-related behaviors in adult male rats that were subjected to binge cocaine treatment during adolescence. We furthermore conducted gene expression analyses of the amygdala 22 hours after the last cocaine injection to identify molecular patterns that might lead to altered emotional processing. RESULTS: Rats injected with cocaine during adolescence displayed less anxiety in adulthood than their vehicle-injected counterparts. In addition, cocaine-exposed animals were deficient in their ability to develop contextual fear responses. Cocaine administration caused transient gene expression changes in the Wnt signaling pathway, of axon guidance molecules, and of synaptic proteins, suggesting that cocaine perturbs dendritic structures and synapses in the amygdala. Phosphorylation of glycogen synthase kinase 3 beta, a kinase in the Wnt signaling pathway, was altered immediately following the binge cocaine paradigm and returned to normal levels 22 hours after the last cocaine injection. CONCLUSIONS: Cocaine exposure during adolescence leads to molecular changes in the amygdala and decreases fear learning and anxiety in adulthood.

Digital microfluidic chips for chemical and biological applications.

The advent of digital microfluidic lab-on-a-chip (LoC) technology offers an excellent platform for developing diagnostic applications. In diagnostics raw physiological samples must be introduced onto the chip and then further processed by lysing blood cells and extracting DNA. However, types of applications that can be implemented on a digital microfluidic platform are largely determined by detection or sensor technology as well as the compatibility of the liquids with electrowetting. In this paper we will focus on analyte detection technologies and discuss suitable applications, both potential and demonstrated, based on digital microfluidics.

Determinants of primary care optometry.

The frequency with which visual problems, ocular disease, and ocular manifestations of systemic disease are experienced in private optometric practice are the determinants of optometry as a primary care profession. This paper describes the basic optometric services provided and shows that these services identify optometry as a primary care profession. A problem-oriented clinical record indicates by color coding the presence of the conditions diagnosed. A computer number assigned to each coded condition and programmed into the system facilitates data retrieval. The color-coded charts provide ready access for review of specific conditions, whereas the computer permits analysis of data concerning the frequency of each of the identified condition.

Reduction of asthenopia after accommodative facility training.

Five patients reporting asthenopia secondary to accommodative deficiencies underwent automated accommodative facility training. A matched-subjects, crossover design was used to control for placebo effects. All patients receiving automated accommodative training showed a marked increase in accommodative amplitude along with a concurrent reduction of asthenopia. Decreases of blur and increases of reading time were the most frequently reported changes by patients. This experiment shows the effectiveness of automated accommodative training in reducing asthenopia and improving accommodative facility.

Ras oncogene point mutations in bladder cancer resistant to cisplatin.

Bladder tumors respond to cisplatin-based chemotherapy in 68% of cases, but only 30% will have a durable response. Recent studies have suggested that ras point mutations may produce cisplatin drug resistance in cell lines. To determine the role of ras point mutations in human tumors resistant to cisplatin, we evaluated ten tumors exposed to cisplatin and eight untreated bladder tumors for ras point mutations. Using polymerase chain reaction DNA amplification and allele-specific oligo-hybridization, we found that only one of the ten treated tumors and none of the untreated tumors harbored a ras point mutation. We conclude that ras point mutations occur infrequently in untreated bladder tumors and do not appear to correlate with cisplatin drug resistance in vivo.