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Relaxor ferroelectric polymers exhibiting a giant electrocaloric effect (ECE) can potentially be used to create next-generation solid-state coolers. Under an electric field, poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer goes through a large dipolar entropy change producing a high adiabatic temperature change (ΔTECE). This work resolves the molecular origins of the large entropy change behind the electric field-induced dipole switching. A Fourier transform infrared spectroscopy equipped with a high voltage source is used to operandoly observe the characteristic molecular vibrational modes. A short-range trans (T) conformation of the CF2-CH2 dyads interrupted by a gauche (G) conformation, e.g., TTTG in the terpolymer chain, undergoes a dynamic transformation that leads to a corresponding ΔTECE whenever an electric field is applied. The molecular dynamics simulation also proves that the energy barrier that the transformation from TTTGs into a long T sequence overcomes is smaller than that for all other conformations. A mixed solvent system is used to obtain T3G-enriched terpolymer films exhibiting a 4.02 K ΔTECE at 60 MVm−1 and these films are employed to manufacture a 2-layer-cascaded cooling device that achieves a 6.7 K temperature lift, the highest reported value for a 2-layer cascaded device made of fluoropolymers.

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'VII: family medicine across the lifespan', authors address the following themes: 'Family medicine maternity care', 'Seeing children as patients brings joy to work', 'Family medicine and the care of adolescents', 'Reproductive healthcare across the lifespan', 'Men's health', 'Care of older adults', and 'Being with dying'. May readers appreciate the range of family medicine in these essays. [ABSTRACT FROM AUTHOR]

The pedunculopontine nucleus (PPN) is a major component of the reticular activating system(RAS) that regulates waking and REM sleep, states of high-frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine PPN, intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis(SubCD). Cortical gamma band activity participates in sensory perception, problem solving,and memory. Rather than participating in the temporal binding of sensory events as in thecortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that (1) the manifestation of gamma band activity during waking may employ aseparate intracellular pathway compared to that during REM sleep, (2) neuronal calciumsens or (NCS-1) protein, which is over expressed in schizophrenia and bipolar disorder,modulates gamma band oscillations in the PPN in a concentration-dependent manner, (3)leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and (4)following our discovery of electrical coupling in the RAS, we hypothesize that there are cellclusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high-frequency activity related to waking and REM sleep by elements of the RAS. [ABSTRACT FROM AUTHOR]

Background: The overuse of antibiotics has rapidly made antimicrobial resistance a global public health challenge. There is an emerging trend where providers who perceive that their patients expect antibiotics are more likely to prescribe antibiotics unprompted or upon request. Particularly, health care providers have expressed concern that dissatisfied patients will provide disparaging online reviews, therefore threatening the reputation of the practice. To better deal with the negative reviews and inform patients, some health care staff directly respond to patients' online feedback. Engaging with patients' online reviews gives providers an opportunity to prevent reputational damage and improve patients' understanding of the antibiotic resistance problem., Objective: We aim to test the effectiveness of different response strategies to the negative patient online reviews on the readers' perceptions of the health care provider and their perceptions related to antibiotics resistance., Methods: Two experiments were conducted to examine the impact of message tactics (apologizing, inducing fear or guilt) that can be employed by health care providers when responding to patients' negative online feedback related to not receiving an antibiotic., Results: Overall, our results demonstrated positive impacts of responding to patients' online reviews. In study 1, we found apologetic messaging and use of emotional appeals in the response were effective in making readers feel more favorable toward the message. Readers also expressed a greater credibility perception toward the provider and willingness to visit the clinic when emotional appeals were used. Findings from study 2 largely supported the effectiveness of a fear-based response in improving the readers' credibility perceptions and willingness to visit the clinic. The fear-inducing information was particularly effective among parent readers., Conclusions: This paper demonstrated that a strategic response to online patient complaints could prevent reputational damage and minimize the potential negative impacts of the review. The results also glean insight into the step toward developing a novel intervention-crafting a persuasive response to patients' negative feedback that can help improve the understanding of antibiotic resistance problems., (©Monique Mitchell Turner, Hyesun Choung, Quoc-Ha Hannah Mai Bui, Paige Beck, Hera Ashraf. Originally published in JMIR Formative Research (https://formative.jmir.org), 22.03.2022.)

This review considers recent evidence showing that cells in three regions of the reticular activating system (RAS) exhibit gamma band activity, and describes the mechanisms behind such manifestation. Specifically, we discuss how cells in the mesopontine pedunculopontine nucleus (PPN), intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD) all fire in the beta/gamma band range when maximally activated, but no higher. The mechanisms behind this ceiling effect have been recently elucidated. We describe recent findings showing that every cell in the PPN have high-threshold, voltage-dependent P/Q-type calcium channels that are essential, while N-type calcium channels are permissive, to gamma band activity. Every cell in the Pf also showed that P/Q-type and N-type calcium channels are responsible for this activity. On the other hand, every SubCD cell exhibited sodium-dependent subthreshold oscillations. A novel mechanism for sleep-wake control based on well-known transmitter interactions, electrical coupling, and gamma band activity is described. The data presented here on inherent gamma band activity demonstrates the global nature of sleep-wake oscillation that is orchestrated by brainstem-thalamic mechanism, and questions the undue importance given to the hypothalamus for regulation of sleep-wakefulness. The discovery of gamma band activity in the RAS follows recent reports of such activity in other subcortical regions like the hippocampus and cerebellum. We hypothesize that, rather than participating in the temporal binding of sensory events as seen in the cortex, gamma band activity manifested in the RAS may help stabilize coherence related to arousal, providing a stable activation state during waking and paradoxical sleep. Most of our thoughts and actions are driven by pre-conscious processes. We speculate that continuous sensory input will induce gamma band activity in the RAS that could participate in the processes of pre-conscious awareness, and provide the essential stream of information for the formulation of many of our actions.

Study Objectives: We recorded the effects of administration of the stimulant modafinil on the amplitude of the sleep state-dependent auditory P13 evoked potential in freely moving rats, a measure of arousal thought to be generated by the cholinergic arm of the reticular activating system, specifically the pedunculopontine nucleus (PPN)., Design: Groups of rats were implanted for recording auditory evoked responses and the effects on P13 potential amplitude of intracranial injections into the PPN of neuroactive agents determined., Measurements and Results: The effects of intracranial injections into the PPN of modafinil showed that P13 potential amplitude increased in a dose-dependent manner at doses of 100, 200, and 300 microM. The effect was blocked by pretreatment with either of the gap junction antagonists carbenoxolone (300 microM) or mefloquine (25 microM), which by themselves slightly decreased P13 potential amplitude., Conclusions: These results suggest that modafinil increases arousal levels as determined by the amplitude of the P13 potential, an effect blocked by gap junction antagonists, suggesting that one mechanism by which modafinil increases arousal may be by increasing electrical coupling.