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Harvesting waste heat for useful purposes is an essential component of improving the efficiency of primary energy utilization. Today, approaches such as pyroelectric energy conversion are receiving renewed interest for their ability to turn wasted energy back into useful energy. From this perspective, the need for these approaches, the basic mechanisms and processes underlying their operation, and the material and device requirements behind pyroelectric energy conversion are reviewed, and the potential for advances in this area is also discussed.

The character of extrinsic contributions to the dielectric and pyroelectric properties of Pb0.99[(Zr0.52Ti0.48)0.98Nb0.02]O3 (PZT) films on Ni foil and Si wafers was explored using Rayleigh analysis, third harmonic phase angle, and Preisach analysis from 15 K to 296 K. The temperature dependence of the domain structure, domain wall mobility, and domain switching influenced the intrinsic, extrinsic, and secondary contributions to the pyroelectric coefficients. This, in turn, produced markedly different room temperature pyroelectric coefficients of ∼250 μC/m2 K and ∼100 μC/m2 K, respectively, for films on Ni and Si. At room temperature, the dielectric irreversible Rayleigh parameter αray was 15.5 ± 0.1 and 28.4 ± 1.6 cm/kV for PZT on Si and Ni, respectively. The higher αray value for the Ni sample suggests more domain wall motion at room temperature, which was attributed to the lower stiffness on the Ni foil compared to the ∼500 μm thick Si substrate. Below 200 K, αray for the PZT Si sample exceeds that of the Ni/PZT sample. This is believed to arise from differences in the energy landscape of pinning centers for the domain wall motion. It is proposed that the residual stresses not only set the preferred domain structures but also the barrier heights for domain wall motion and domain switching. [ABSTRACT FROM AUTHOR]

The dramatic increase in the pyroelectric coefficient around the ferroelectric–paraelectric phase transition suggests high potential energy conversion efficiencies, but the reality is more complicated when thermal and electrical losses are considered. The performance of prototype mono-domain lead titanate thin films is simulated around phase transition using a phenomenological modeling approach. Thermodynamic properties are calculated using a modified Landau–Devonshire potential that is a function of temperature, applied electric field, and uniaxial tensile stress for bulk films. Significant performance enhancement near the ferroelectric–paraelectric phase transition is observed. However, increases in both the specific heat and the dielectric constant reduced the anticipated improvement. Critically, electrical losses during charging and discharging processes within the energy conversion cycle are included and calculated using the dielectric dissipation factor. Cascaded pyroelectric conversion cycles are considered where heat for each subsequent stage is provided by the previous stage, allowing for the segmentation of large temperature changes into multiple cycles. The implementation of a multi-stage or cascade approach could greatly increase the cycle efficiency over a large temperature range while utilizing lower, more realistic, electric field strengths. We show how each stage could be optimized through a secondary multi-caloric effect where the ferroelectric–paraelectric transition temperature is shifted using an applied biaxial stress. Loss tangents as low as 5% are shown to negate the benefits of cascading for high number of stages (n > 10). Using a stress-tuned optimum phase transition temperature for cascade stages provides roughly a 100% increase in thermal efficiency vs the unoptimized material for low electric field cycles. [ABSTRACT FROM AUTHOR]

We report the dielectric response and resistive switching properties of bilayers of PbZr0.40Ti0.60O3 [PZT (40:60)] and HfO2 of varying thickness on platinized Si substrates. PZT (40:60) and HfO2 films were grown using chemical solution deposition and atomic layer deposition, respectively. We show here that the addition of an interposed linear dielectric layer with a high permittivity between the ferroelectric film and the top electrode modifies the polarization and resistive switching characteristics of the multilayer stack. We observe an increase in the coercive field by 45% for PZT films of 250 nm thickness with a 20 nm HfO2 layer compared to 250 nm thick PZT films grown under identical conditions. Simultaneously, the dielectric constant decreases by 43% from 409 to 175 for a 250 nm PZT film with 20 nm HfO2, accompanied by a significant improvement in the leakage current density from 5.6 × 10−4 A/cm2 to 8.7 × 10−8 A/cm2. Our resistance measurements show that there are two separate resistance states that are accessible with at least an order of magnitude in resistance difference from 5 × 108 to 5 × 109 Ω. We show that the dielectric response and the coercivity of the bilayer system can be explained by a capacitors-in-series model. This indicates that the PZT and the HfO2 layer could effectively be considered decoupled, presumably due to bound/trapped charges at the interlayer interface. This charged ferroelectric/dielectric interface could be the reason for the intermediate resistance states which could be used as multistate resistive memories in neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

An understanding of the pyroelectric coefficient and particularly its relationship with the applied electric field is critical to predicting the device performance for infrared imaging, energy harvesting, and solid-state cooling devices. In this work, we compare direct measurements of the pyroelectric effect under pulsed heating to the indirect extraction of the pyroelectric coefficient from adiabatic hysteresis loops and predictions from Landau-Devonshire theory for PbZr0.52Ti0.48O3 (PZT 52/48) on platinized silicon substrates. The differences between these measurements are explained through a series of careful measurements that quantify the magnitude and direction of the secondary and field-induced pyroelectric effects. The indirect measurement is shown to be up to 25% of the direct measurement at high fields, while the direct measurements and theoretical predictions converge at high fields as the film approaches a mono-domain state. These measurements highlight the importance of directly measuring the pyroelectric response in thin films, where non-intrinsic effects can be a significant proportion of the total observed pyroelectricity. Material and operating conditions are also discussed which could simultaneously maximize all contributions to pyroelectricity. [ABSTRACT FROM AUTHOR]

A multi-step plasma etching technique is developed to obtain deep-grooved micro-scale ball-bearing raceways and employed in the fabrication of multiple ball-bearing supported microturbines. Deep-groove geometry has been chosen for the microball-bearing systems because of the ability to handle mixed axial and radial loads, allowing for stable, high-speed operation compared to previous iterations of the microball-bearing raceways. The multi-step inductively coupled plasma-based process is optimized to obtain <2% deviation amongst intended raceway depth, width and curvature. Etching non-uniformity is measured to be 0.15% within the raceway of a single device. The bearing dynamics with the new deep-groove geometry have been simulated. The deep-groove raceway packed with off-the-shelf precision ball-bearings provided a stability improvement over previous demonstrations of high-performance rotary micromachines operating at high speeds. [ABSTRACT FROM AUTHOR]

Thin-film materials with large electromechanical responses are fundamental enablers of next-generation micro-/nano-electromechanical applications. Conventional electromechanical materials (for example, ferroelectrics and relaxors), however, exhibit severely degraded responses when scaled down to submicrometre-thick films due to substrate constraints (clamping). This limitation is overcome, and substantial electromechanical responses in antiferroelectric thin films are achieved through an unconventional coupling of the field-induced antiferroelectric-to-ferroelectric phase transition and the substrate constraints. A detilting of the oxygen octahedra and lattice-volume expansion in all dimensions are observed commensurate with the phase transition using operando electron microscopy, such that the in-plane clamping further enhances the out-of-plane expansion, as rationalized using first-principles calculations. In turn, a non-traditional thickness scaling is realized wherein an electromechanical strain (1.7%) is produced from a model antiferroelectric PbZrO 3 film that is just 100 nm thick. The high performance and understanding of the mechanism provide a promising pathway to develop high-performance micro-/nano-electromechanical systems., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Objective: 20-40% of individuals whose seizures are not controlled by anti-seizure medications exhibit manifestations comparable to epileptic seizures (ES), but there are no EEG correlates. These events are called functional or dissociative seizures (FDS). Due to limited access to EEG-monitoring and inconclusive results, we aimed to develop an alternative diagnostic tool that distinguishes ES vs. FDS. We evaluated the temporal evolution of ECG-based measures of autonomic function (heart rate variability, HRV) to determine whether they distinguish ES vs. FDS., Methods: The prospective study includes patients admitted to the University of Rochester Epilepsy Monitoring Unit. Participants are 18-65 years old, without therapies or co-morbidities associated with altered autonomics. A habitual ES or FDS is recorded during admission. HRV analysis is performed to evaluate the temporal changes in autonomic function during the peri‑ictal period (150-minutes each pre-/post-ictal). We determined if autonomic measures distinguish ES vs. FDS., Results: The study includes 53 ES and 46 FDS. Temporal evolution of HR and autonomics significantly differ surrounding ES vs. FDS. The pre-to-post-ictal change (delta) in HR differs surrounding ES vs. FDS, stratified for convulsive and non-convulsive events. Post-ictal HR, total autonomic (SDNN & Total Power), vagal (RMSSD & HF), and baroreflex (LF) function differ for convulsive ES vs. convulsive FDS. HR distinguishes non-convulsive ES vs. non-convulsive FDS with ROC>0.7, sensitivity>70%, but specificity<50%. HR-delta and post-ictal HR, SDNN, RMSSD, LF, HF, and Total Power each distinguish convulsive ES vs. convulsive FDS (ROC, 0.83-0.98). Models with HR-delta and post-ictal HR provide the highest diagnostic accuracy for convulsive ES vs. convulsive FDS: 92% sensitivity, 94% specificity, ROC 0.99)., Significance: HR and HRV measures accurately distinguish convulsive, but not non-convulsive, events (ES vs. FDS). Results establish the framework for future studies to apply this diagnostic tool to more heterogeneous populations, and on out-of-hospital recordings, particularly for populations without access to epilepsy monitoring units., Competing Interests: Declaration of Competing Interest Justin M. Ryan reports no disclosures. Kyle T. Wagner reports no disclosures. Sushma Yerram reports no disclosures. Cathleen Concannon reports no disclosures. Jennifer X. Lin reports no disclosures. Patrick Rooney reports no disclosures. Brian Hanrahan reports no disclosures. Victoria Titoff reports no disclosures. Noreen L. Connolly reports no disclosures. Ramona Cranmer reports no disclosures. Natalia DeMaria reports no disclosures. Xiaojuan Xia reports no disclosures. Betty Mykins reports no disclosures. Steven Erickson reports no disclosures. Jean-Philippe Couderc reports no disclosures. Giovanni Schifitto reports no disclosures. Inna Hughes reports no disclosures. Dongliang Wang reports no disclosures. Giuseppe Erba reports no disclosures. David S. Auerbach reports no disclosures., (Copyright © 2023 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Antiferroelectrics, which undergo a field-induced phase transition to ferroelectric order that manifests as double-hysteresis polarization switching, exhibit great potential for dielectric, electromechanical, and electrothermal applications. Compared to their ferroelectric cousins, however, considerably fewer efforts have been made to understand and control antiferroelectrics. Here, it is demonstrated that the polarization switching behavior of an antiferroelectric can be strongly influenced and effectively regulated by point defects. In films of the canonical antiferroelectric PbZrO 3 , decreasing oxygen pressure during deposition (and thus increasing adatom kinetic energy) causes unexpected "ferroelectric-like" polarization switching although the films remain in the expected antiferroelectric orthorhombic phase. This "ferroelectric-like" switching is correlated with the creation of bombardment-induced point-defect complexes which pin the antiferroelectric-ferroelectric phase boundaries, and thus effectively delay the phase transition under changing field. The effective pinning energy is extracted via temperature-dependent switching-kinetics studies. In turn, by controlling the concentration of defect complexes, the dielectric tunability of the PbZrO 3 can be adjusted, including being able to convert between "positive" and "negative" tunability near zero field. This work reveals the important role and strong capability of defects to engineer antiferroelectrics for new performance and functionalities., (© 2023 Wiley-VCH GmbH.)

Growing annual crops such as corn (Zea mays L.) can lead to considerable nutrient losses through subsurface drainage in agricultural fields, posing a serious threat to surface water quality in the midwestern United States. Perennial crops have the potential to reduce these nutrient losses. However, more comprehensive data are needed on the nutrient loss effect of perennial crops. We examined the effect of alfalfa (Medicago sativa L.) on nitrate-nitrogen (NO 3 -N), total nitrogen (TN), dissolved reactive phosphorus (DRP), and total phosphorus (TP) in subsurface drainage using a before-after-control-impact (BACI) experimental design with one control field (with annual crops) and one impact field (with alfalfa) each on two farms (Sites A and B) located in northwestern Ohio. The "Before" period (prior to planting alfalfa at the impact field) extended for 4 yr (2013-2017) at Site A and 6 yr (2011-2017) at Site B; the "After" period extended for an additional 2 yr at both sites. Reductions in the mean monthly discharge and loads of NO - -N, TN, DRP, and TP were significant at Site A, whereas the only significant change at site B was a reduction in the mean monthly TP load. Significant reductions in NO 3 - -N, TN, DRP, and TP were significant at Site A, whereas the only significant change at site B was a reduction in the mean monthly TP load. Significant reductions in NO 3 - -N loads were observed during spring and winter at Site A. In addition, alfalfa reduced the variability of discharge and nutrient loads through subsurface drainage at both sites. Our findings suggest that introducing alfalfa into annual crop rotations has the potential to reduce subsurface nutrient loads and increase the resiliency of agricultural systems., (© 2022 The Authors. Journal of Environmental Quality © 2022 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Currently, there is a lack of nonvolatile memory (NVM) technology that can operate continuously at temperatures > 200 °C. While ferroelectric NVM has previously demonstrated long polarization retention and >1013 read/write cycles at room temperature, the largest hurdle comes at higher temperatures for conventional perovskite ferroelectrics. Here, we demonstrate how AlScN can enable high-temperature (>200 °C) nonvolatile memory. The c-axis textured thin films were prepared via reactive radiofrequency magnetron sputtering onto a highly textured Pt (111) surface. Photolithographically defined Pt top electrodes completed the capacitor stack, which was tested in a high temperature vacuum probe station up to 400 °C. Polarization−electric field hysteresis loops between 23 and 400 °C reveal minimal changes in the remanent polarization values, while the coercive field decreased from 4.3 MV/cm to 2.6 MV/cm. Even at 400 °C, the polarization retention exhibited negligible loss for up to 1000 s, demonstrating promise for potential nonvolatile memory capable of high−temperature operation. Fatigue behavior also showed a moderate dependence on operating temperature, but the mechanisms of degradation require additional study.

This paper demonstrates laser forming, localized heating with a laser to induce plastic deformation, can self-fold 2D printed circuit boards (PCBs) into 3D structures with electronic function. There are many methods for self-folding but few are compatible with electronic materials. We use a low-cost commercial laser writer to both cut and fold a commercial flexible PCB. Laser settings are tuned to select between cutting and folding with higher power resulting in cutting and lower power resulting in localized heating for folding into 3D shapes. Since the thin copper traces used in commercial PCBs are highly reflective and difficult to directly fold, two approaches are explored for enabling folding: plating with a nickel/gold coating or using a single, high-power laser exposure to oxidize the surface and improve laser absorption. We characterized the physical effect of the exposure on the sample as well as the fold angle as a function of laser passes and demonstrate the ability to lift weights comparable with circuit packages and passive components. This technique can form complex, multifold structures with integrated electronics; as a demonstrator, we fold a commercial board with a common timing circuit. Laser forming to add a third dimension to printed circuit boards is an important technology to enable the rapid prototyping of complex 3D electronics.

The hafnate perovskites PbHfO 3 (antiferroelectric) and SrHfO 3 ("potential" ferroelectric) are studied as epitaxial thin films on SrTiO 3 (001) substrates with the added opportunity of observing a morphotropic phase boundary (MPB) in the Pb 1- x Sr x HfO 3 system. The resulting (240)-oriented PbHfO 3 (Pba2) films exhibited antiferroelectric switching with a saturation polarization ≈53 µC cm -2 at 1.6 MV cm -1 , weak-field dielectric constant ≈186 at 298 K, and an antiferroelectric-to-paraelectric phase transition at ≈518 K. (002)-oriented SrHfO 3 films exhibited neither ferroelectric behavior nor evidence of a polar P4mm phase . Instead, the SrHfO 3 films exhibited a weak-field dielectric constant ≈25 at 298 K and no signs of a structural transition to a polar phase as a function of temperature (77-623 K) and electric field (-3 to 3 MV cm -1 ). While the lack of ferroelectric order in SrHfO 3 removes the potential for MPB, structural and property evolution of the Pb 1- x Sr x HfO 3 (0 ≤ x < 1) system is explored. Strontium alloying increased the electric-breakdown strength (E B ) and decreased hysteresis loss, thus enhancing the capacitive energy storage density (U r ) and efficiency (η). The composition, Pb 0.5 Sr 0.5 HfO 3 produced the best combination of E B  = 5.12 ± 0.5 MV cm -1 , U r  = 77 ± 5 J cm -3 , and η = 97 ± 2%, well out-performing PbHfO 3 and other antiferroelectric oxides., (© 2021 Wiley-VCH GmbH.)

Objective: To determine whether the standardization and implementation of an ictal testing protocol in the Epilepsy Monitoring Unit (EMU) leads to improvements in ictal testing performance., Methods: Ictal assessments completed in the EMU from a single center were retrospectively reviewed over a two-month period. Each assessment was evaluated to determine whether 8 high-yield aspects of the ictal assessment were performed. Following observation of performance, a standardized ictal testing protocol was developed based on a root cause analysis and review of consensus guidelines. This protocol was disseminated to staff in conjunction with an annual epilepsy education seminar. Ictal assessment performance was re-assessed during the subsequent two months (short-term follow-up) and again during a five- to seven-month period (long-term follow-up) beyond the initial intervention. For sub-group analysis, event characteristics (event type, time of assessment) and patient characteristics (age, gender) were also evaluated and analyzed in relation to ictal testing performance., Results: All eight individual ictal testing elements were more likely to be assessed in short-term and long-term follow-up periods when compared to pre-intervention assessments. The cumulative difference in ictal testing was 20.4% (95% CI 3.7-37.2, p = 0.02) greater for the short-term period and 16.7% (95% CI -0.3% to 33.8%, p = 0.05) greater in the long-term period when compared to baseline testing., Conclusions: Utilization of a standardized ictal testing battery in conjunction with staff education leads to an objective improvement in ictal assessment performance. Further research is warranted to assess the replicability of our findings., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: To analyze the impact of interview date on the applicant rank for Neurology residencies in the United States., Methods: A multi-institutional retrospective review of interview dates and applicant rank list data for the National Resident Matching Program (NRMP) was conducted for five Neurology programs, totaling 1932 interviewed applicants over a combined total of 31 interview years. For each candidate, the interview date and applicant rank were abstracted along with the total number of interviews for that season. Statistical analyses were completed on the cumulative institution data set as well for each individual institution to assess for a possible relationship between interview date and applicant rank., Results: The cumulative institutional analysis showed that the mean applicant rank decreased as the interview season progressed. Applicants who interviewed on the first day of the interview season were ranked 11.4% higher than those who interviewed on the last interview day. Additionally, applicants interviewed on the first interview day more likely to be ranked higher when compared to all other interview dates. Independent analysis of each program's data identified comparable, statistically significant, differences in mean applicant rank and interview position at three out of the five institutions., Conclusions: This study evaluated the impact of interview order on the ranking of applicants by Neurology residency programs, noting a temporal relationship with applicant rank and interview date. The primacy bias appreciated in our data merits further evaluation in other medical specialties. Strategies to minimize the impact of this bias should be employed by residency programs who use medical matching services., (© 2021 John Wiley & Sons Ltd and The Association for the Study of Medical Education.)

The Pacinian corpuscle is a highly sensitive mammalian sensor cell that exhibits a unique band-pass sensitivity to vibrations. The cell achieves this band-pass response through the use of 20 to 70 elastic layers entrapping layers of viscous fluid. This paper develops and explores a scalable mechanical model of the Pacinian corpuscle and uses the model to predict the response of synthetic corpuscles, which could be the basis for future vibration sensors. The -3dB point of the biological cell is accurately mimicked using the geometries and materials available with off-the-shelf 3D printers. The artificial corpuscles here are constructed using uncured photoresist within structures printed in a commercial stereolithography (SLA) 3D printer, allowing the creation of trapped fluid layers analogous to the biological cell. Multi-layer artificial Pacinian corpuscles are vibration tested over the range of 20-3000 Hz and the response is in good agreement with the model.

A vibration sensor is presented mimicking the structure of the Pacinian corpuscle. A multi-step casting process is used to create a 5 mm diameter sensor with a liquid metal core, elastomer dielectric, and graphite counter electrode creating a spherical capacitive sensing element with sensitivities on the order of 10 Δ pF/mm -1 . A model for the capacitance change of the spherical capacitor as it is formed is developed and its findings support the sensitivities observed. Various elastomer dielectric compositions with integrated barium titanate nanoparticles are tested to increase the dielectric constant. The biological acoustic filter within the corpuscle is mimicked using alternating cast layers of oligomers and elastomers around the spherical sensor element. Vibration sensing is characterized over the low frequency range of 10-300 Hz and the minimum detectable sensitivity is found to be 1 µm with a low power requirement of 7 mW. The artificial Pacinian corpuscle has potential applications in tactile sensing and seismic monitoring devices.

Our goal was to evaluate how accurate neurologists are at differentiating between different paroxysmal events based on clinical history versus observation of the spell in question. Forty-seven neurologists reviewed 12 clinical histories and videos of recorded events of patients admitted in the Epilepsy Monitoring Unit (EMU). They were asked to diagnose events as epileptic seizures, non-epileptic behavioral spells (NEBS), or other physiologic events as well as rate their confidence in their diagnosis. The median diagnostic accuracy for all paroxysmal events was 67% for clinical history and 75% for observation (p=.001). This was largely due to the difference in accuracy within the subgroup of patients with NEBS (67% history vs. 83% observation, p<.001). There were trends for higher diagnostic accuracy and increased inter-rater agreement with higher levels of training. Physicians with higher levels of training were more confident with diagnosis based on observation. In summary, reviewing videos of paroxysmal spells may improve diagnostic accuracy and enhance the evaluation of patients. Neurologists at all levels of training should encourage the recording and review of videos of recurrent spells to aid in medical decision-making especially when there is high concern that the spells in question are NEBS., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objectives: Preoxygenation prior to intubation aims to increase the duration of safe apnea by causing denitrogenation of the functional residual capacity, replacing this volume with a reservoir of oxygen. In the operating room (OR) the criterion standard for preoxygenation is an anesthetic circuit and well-fitting face mask, which provide a high fractional inspired oxygen concentration (FiO2 ). Outside of the OR, various strategies exist to provide preoxygenation. The objective was to evaluate the effectiveness of commonly used preoxygenation strategies outside of the OR environment., Methods: This was a prospective randomized unblinded study of 30 healthy staff volunteers from a major trauma center emergency department (ED) in Sydney, Australia. The main outcome measure is fractional expired oxygen concentration (FeO2 ) measured after a 3-minute period of tidal volume breathing with seven different preoxygenation strategies., Results: The mean FeO2 achieved with the anesthetic circuit was 81.0% (95% confidence interval [CI] = 78.3% to 83.6%), bag-valve-mask (BVM) 80.1% (95% CI = 76.5% to 83.6%), BVM with nasal cannula (NC) 74.8% (95% CI = 72.0% to 77.6%), BVM with positive end-expiratory pressure valve (PEEP) 78.9% (95% CI = 75.4% to 82.3%), BVM + NC + PEEP 75.5% (95% CI = 72.2% to 78.9%), nonrebreather mask (NRM) 51.6% (95% CI = 48.8% to 54.4%), and NRM + NC 57.1% (95% CI = 52.9% to 61.2%). Preoxygenation efficacy with BVM strategies was significantly greater than NRM strategies (p < 0.01) and noninferior to the anesthetic circuit., Conclusions: In healthy volunteers, the effectiveness of BVM preoxygenation was comparable to the anesthetic circuit (criterion standard) and superior to preoxygenation with NRM. The addition of NC oxygen, PEEP, or both did not improve the efficacy of the BVM device., (© 2016 by the Society for Academic Emergency Medicine.)

Overcoming specific fears and subsequent anxiety can be greatly enhanced by the presence of familiar social partners, but the neural circuitry that controls this phenomenon remains unclear. To overcome this, the social interaction (SI) habituation test was developed in this lab to systematically investigate the effects of social familiarity on anxiety-like behavior in rats. Here, we show that social familiarity selectively reduced anxiety-like behaviors induced by an ethological anxiogenic stimulus. The anxiolytic effect of social familiarity could be elicited over multiple training sessions and was specific to both the presence of the anxiogenic stimulus and the familiar social partner. In addition, socially familiar conspecifics served as a safety signal, as anxiety-like responses returned in the absence of the familiar partner. The expression of the social familiarity-induced anxiolysis (SFiA) appears dependent on the prefrontal cortex (PFC), an area associated with cortical regulation of fear and anxiety behaviors. Inhibition of the PFC, with bilateral injections of the GABAA agonist muscimol, selectively blocked the expression of SFiA while having no effect on SI with a novel partner. Finally, the effect of D-cycloserine, a cognitive enhancer that clinically enhances behavioral treatments for anxiety, was investigated with SFiA. D-cycloserine, when paired with familiarity training sessions, selectively enhanced the rate at which SFiA was acquired. Collectively, these outcomes suggest that the PFC has a pivotal role in SFiA, a complex behavior involving the integration of social cues of familiarity with contextual and emotional information to regulate anxiety-like behavior.

The characteristics and capabilities of a light-scattering microemboli detector (LSMD) are delineated by detailing its state-of-the-art configuration, by discussing the theoretical and empirical aspects of instrument calibration, and by summarizing various experimental studies that have benefited from this instrument. In the past, thromboembolism, which often results when blood contacts medical devices, has eluded scientific scrutiny due to the absence of instruments that could detect and quantify thromboemboli in circulating blood. More recently, the ability of the LSMD to provide continuous, noninvasive detection of thromboemboli in whole blood (meaning that the LSMD probe does not contact the blood) was exploited in various in vitro and ex vivo models to explore thromboembolic phenomena. Through this work, the LSMD evolved as a sensitive and an economical research tool for the study of thromboembolic phenomena., (Copyright 2003 Society of Photo-Optical Instrumentation Engineers)

Multiple sclerosis (MS) is a fairly common condition that affects approximately 350,000 people in the United States. It is associated with various neuropsychiatric symptoms including cognitive and behavioral symptoms. However, visual hallucinations are rare in multiple sclerosis without the presence of cognitive deficits. We are describing the case of a 40-year-old married white female with isolated complex visual hallucinations compatible with the Charles Bonnet syndrome (CBS). The patient was successfully treated with the atypical antipsychotic olanzapine.