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JT Sutton,1 JL Raymond,1 MC Verleye,2 GJ Pyne-Geithman,3 CK Holland4 1University of Cincinnati, Biomedical Engineering Program, Cincinnati, OH, 2University of Notre Dame Department of Chemical Engineering, Notre Dame, IN, 3University of Cincinnati, College of Medicine, Department of Neurosurgery and the University of Cincinnati Neuroscience Institute, and Mayfield Clinic, Cincinnati, OH, 4University of Cincinnati, College of Medicine, Internal Medicine, Division of Cardiovascular Diseases, Cincinnati, OH, USA Abstract: Ultrasound-mediated drug delivery is a novel technique for enhancing the penetration of drugs into diseased tissue beds noninvasively. By encapsulating drugs into microsized and nanosized liposomes, the therapeutic can be shielded from degradation within the vasculature until delivery to a target site by ultrasound exposure. Traditional in vitro or ex vivo techniques to quantify this delivery profile include optical approaches, cell culture, and electrophysiology. Here, we demonstrate an approach to characterize the degree of nitric oxide (NO) delivery to porcine carotid tissue by direct measurement of ex vivo vascular tone. An ex vivo perfusion model was adapted to assess ultrasound-mediated delivery of NO. This potent vasodilator was coencapsulated with inert octafluoropropane gas to produce acoustically active bubble liposomes. Porcine carotid arteries were excised post mortem and mounted in a physiologic buffer solution. Vascular tone was assessed in real time by coupling the artery to an isometric force transducer. NO-loaded bubble liposomes were infused into the lumen of the artery, which was exposed to 1 MHz pulsed ultrasound at a peak-to-peak acoustic pressure amplitude of 0.34 MPa. Acoustic cavitation emissions were monitored passively. Changes in vascular tone were measured and compared with control and sham NO bubble liposome exposures. Our results demonstrate that ultrasound-triggered NO release from bubble liposomes induces potent vasorelaxation within porcine carotid arteries (maximal relaxation 31%±8%), which was significantly stronger than vasorelaxation due to NO release from bubble liposomes in the absence of ultrasound (maximal relaxation 7%±3%), and comparable with relaxation due to 12 µM sodium nitroprusside infusions (maximal relaxation 32%±3%). This approach is a valuable mechanistic tool for assessing the extent of drug release and delivery to the vasculature caused by ultrasound. Keywords: ultrasound-mediated drug delivery, bubble liposomes, nitric oxide

Systems consolidation is a common feature of learning and memory systems, in which a long-term memory initially stored in one brain region becomes persistently stored in another region. We studied the dynamics of systems consolidation in simple circuit architectures with two sites of plasticity, one in an early-learning and one in a late-learning brain area. We show that the synaptic dynamics of the circuit during consolidation of an analog memory can be understood as a temporal integration process, by which transient changes in activity driven by plasticity in the early-learning area are accumulated into persistent synaptic changes at the late-learning site. This simple principle naturally leads to a speed-accuracy tradeoff in systems consolidation and provides insight into how the circuit mitigates the stability-plasticity dilemma of storing new memories while preserving core features of older ones. Furthermore, it imposes two constraints on the circuit. First, the plasticity rule at the late-learning site must stably support a continuum of possible outputs for a given input. We show that this is readily achieved by heterosynaptic but not standard Hebbian rules. Second, to turn off the consolidation process and prevent erroneous changes at the late-learning site, neural activity in the early-learning area must be reset to its baseline activity. We provide two biologically plausible implementations for this reset that propose functional roles in stabilizing consolidation for core elements of the cerebellar circuit., Competing Interests: Competing interests statement:The authors declare no competing interest.

In 2022, mpox virus (MPXV) spread worldwide, causing 99,581 mpox cases in 121 countries. Modified vaccinia Ankara (MVA) vaccine use reduced disease in at-risk populations but failed to deliver complete protection. Lag in manufacturing and distribution of MVA resulted in additional MPXV spread, with 12,000 reported cases in 2023 and an additional outbreak in Central Africa of clade I virus. These outbreaks highlight the threat of zoonotic spillover by Orthopoxviruses. mRNA-1769, an mRNA-lipid nanoparticle (LNP) vaccine expressing MPXV surface proteins, was tested in a lethal MPXV primate model. Similar to MVA, mRNA-1769 conferred protection against challenge and further mitigated symptoms and disease duration. Antibody profiling revealed a collaborative role between neutralizing and Fc-functional extracellular virion (EV)-specific antibodies in viral restriction and ospinophagocytic and cytotoxic antibody functions in protection against lesions. mRNA-1769 enhanced viral control and disease attenuation compared with MVA, highlighting the potential for mRNA vaccines to mitigate future pandemic threats., Competing Interests: Declaration of interests Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the US Army. A.W.F., D.C., C.A., H.N., G.S., T.R.F., R.H.L., A.M., G.A.A., D.S., P.A.J., H.B., J.C.J., K.H., A.C., W.-H.Y., and G.A. are employees of Moderna. G.A. is an equity holder in Systems Seromyx and Leyden Labs and has received collaborative funding from Moderna, GSK, Sanofi, Medicago, BioNtech, Clover, and Pfizer in the past year. P.L.E., J.L.A., C.A.C., and B.M. were supported by the Division of Intramural Research, NIAID, NIH., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The relationship between economic growth and CO 2 emissions has been analyzed testing the environmental Kuznets curve hypothesis, but traditional econometric methods may be flawed. An alternative method is proposed using segmented-sample regressions and implemented in 164 countries (98.34% of world population) over different periods from 1822 to 2018. Results suggest that while the association between GDP per capita and CO 2 emissions per capita is weakening over time, it remains positive globally, with only some high-income countries showing a reversed association in recent years. While 49 countries have decoupled emissions from economic growth, 115 have not. Most African, American, and Asian countries have not decoupled, whereas most European and Oceanians have. These findings highlight the urgency for effective climate policies because decoupling remains unachieved on a global scale, and we are moving away from, rather than approaching, the Paris Agreement goal of limiting temperature increase to 1.5 °C above preindustrial levels., (© 2024. The Author(s).)

The enhancement of associative synaptic plasticity often results in impaired rather than enhanced learning. Previously, we proposed that such learning impairments can result from saturation of the plasticity mechanism (Nguyen-Vu et al., 2017), or, more generally, from a history-dependent change in the threshold for plasticity. This hypothesis was based on experimental results from mice lacking two class I major histocompatibility molecules, MHCI H2-K b and H2-D b (MHCI K b D b-/- ), which have enhanced associative long-term depression at the parallel fiber-Purkinje cell synapses in the cerebellum (PF-Purkinje cell LTD). Here, we extend this work by testing predictions of the threshold metaplasticity hypothesis in a second mouse line with enhanced PF-Purkinje cell LTD, the Fmr1 knockout mouse model of Fragile X syndrome (FXS). Mice lacking Fmr1 gene expression in cerebellar Purkinje cells (L7- Fmr1 KO) were selectively impaired on two oculomotor learning tasks in which PF-Purkinje cell LTD has been implicated, with no impairment on LTD-independent oculomotor learning tasks. Consistent with the threshold metaplasticity hypothesis, behavioral pre-training designed to reverse LTD at the PF-Purkinje cell synapses eliminated the oculomotor learning deficit in the L7- Fmr1 KO mice, as previously reported in MHCI K b D b-/- mice. In addition, diazepam treatment to suppress neural activity and thereby limit the induction of associative LTD during the pre-training period also eliminated the learning deficits in L7- Fmr1 KO mice. These results support the hypothesis that cerebellar LTD-dependent learning is governed by an experience-dependent sliding threshold for plasticity. An increased threshold for LTD in response to elevated neural activity would tend to oppose firing rate stability, but could serve to stabilize synaptic weights and recently acquired memories. The metaplasticity perspective could inform the development of new clinical approaches for addressing learning impairments in autism and other disorders of the nervous system., Competing Interests: AS, JF, AN, JB No competing interests declared, JR Reviewing editor, eLife, (© 2023, Shakhawat et al.)

Determining the sites and directions of plasticity underlying changes in neural activity and behavior is critical for understanding mechanisms of learning. Identifying such plasticity from neural recording data can be challenging due to feedback pathways that impede reasoning about cause and effect. We studied interactions between feedback, neural activity, and plasticity in the context of a closed-loop motor learning task for which there is disagreement about the loci and directions of plasticity: vestibulo-ocular reflex learning. We constructed a set of circuit models that differed in the strength of their recurrent feedback, from no feedback to very strong feedback. Despite these differences, each model successfully fit a large set of neural and behavioral data. However, the patterns of plasticity predicted by the models fundamentally differed, with the direction of plasticity at a key site changing from depression to potentiation as feedback strength increased. Guided by our analysis, we suggest how such models can be experimentally disambiguated. Our results address a long-standing debate regarding cerebellum-dependent motor learning, suggesting a reconciliation in which learning-related changes in the strength of synaptic inputs to Purkinje cells are compatible with seemingly oppositely directed changes in Purkinje cell spiking activity. More broadly, these results demonstrate how changes in neural activity over learning can appear to contradict the sign of the underlying plasticity when either internal feedback or feedback through the environment is present., Competing Interests: HP, MG No competing interests declared, JR Reviewing editor, eLife, (© 2024, Payne et al.)

Smallpox was the most rampant infectious disease killer of the 20th century, yet much remains unknown about the pathogenesis of the variola virus. Using archived tissue from a study conducted at the Centers for Disease Control and Prevention we characterized pathology in 18 cynomolgus macaques intravenously infected with the Harper strain of variola virus. Six macaques were placebo-treated controls, six were tecovirimat-treated beginning at 2 days post-infection, and six were tecovirimat-treated beginning at 4 days post-infection. All macaques were treated daily until day 17. Archived tissues were interrogated using immunohistochemistry, in situ hybridization, immunofluorescence, and electron microscopy. Gross lesions in three placebo-treated animals that succumbed to infection primarily consisted of cutaneous vesicles, pustules, or crusts with lymphadenopathy. The only gross lesions noted at the conclusion of the study in the three surviving placebo-treated and the Day 4 treated animals consisted of resolving cutaneous pox lesions. No gross lesions attributable to poxviral infection were present in the Day 2 treated macaques. Histologic lesions in three placebo-treated macaques that succumbed to infection consisted of proliferative and necrotizing dermatitis with intracytoplasmic inclusion bodies and lymphoid depletion. The only notable histologic lesion in the Day 4 treated macaques was resolving dermatitis; no notable lesions were seen in the Day 2 treated macaques. Variola virus was detected in all three placebo-treated animals that succumbed to infection prior to the study's conclusion by all utilized methods (IHC, ISH, IFA, EM). None of the three placebo-treated animals that survived to the end of the study nor the animals in the two tecovirimat treatment groups showed evidence of variola virus by these methods. Our findings further characterize variola lesions in the macaque model and describe new molecular methods for variola detection., Competing Interests: DWG and DEH are employed by SIGA Technologies. SIGA Technologies holds commercial interest in tecovirimat and provided tecovirimat for the study referenced. Other authors have no conflict of interest., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Background: Youth with traumatic injury experience elevated risk for behavioral health disorders, yet posthospital monitoring of patients' behavioral health is rare. The Telehealth Resilience and Recovery Program (TRRP), a technology-facilitated and stepped access-to-care program initiated in hospitals and designed to be integrated seamlessly into trauma center operations, is a program that can potentially address this treatment gap. However, the TRRP was originally developed to address this gap for mental health recovery but not substance use. Given the high rates of substance and opioid use disorders among youth with traumatic injury, there is a need to monitor substance use and related symptoms alongside other mental health concerns., Objective: This study aimed to use an iterative, user-guided approach to inform substance use adaptations to TRRP content and procedures., Methods: We conducted individual semistructured interviews with adolescents (aged 12-17 years) and young adults (aged 18-25 years) who were recently discharged from trauma centers (n=20) and health care providers from two level 1 trauma centers (n=15). Interviews inquired about reactions to and recommendations for expanding TRRP content, features, and functionality; factors related to TRRP implementation and acceptability; and current strategies for monitoring patients' postinjury physical and emotional recovery and opioid and substance use. Interview responses were transcribed and analyzed using thematic analysis to guide new TRRP substance use content and procedures., Results: Themes identified in interviews included gaps in care, task automation, user personalization, privacy concerns, and in-person preferences. Based on these results, a multimedia, web-based mobile education app was developed that included 8 discrete interactive education modules and 6 videos on opioid use disorder, and TRRP procedures were adapted to target opioid and other substance use disorder risk. Substance use adaptations included the development of a set of SMS text messaging-delivered questions that monitor both mental health symptoms and substance use and related symptoms (eg, pain and sleep) and the identification of validated mental health and substance use screening tools to monitor patients' behavioral health in the months after discharge., Conclusions: Patients and health care providers found the TRRP and its expansion to address substance use acceptable. This iterative, user-guided approach yielded novel content and procedures that will be evaluated in a future trial., (©Zachary W Adams, Brigid R Marriott, Swathi Karra, Elizabeth Linhart-Musikant, Jodi L Raymond, Lydia J Fischer, Kristina A Bixler, Teresa M Bell, Eric A Bryan, Leslie A Hulvershorn. Originally published in JMIR Formative Research (https://formative.jmir.org), 30.11.2023.)

Sonochemistry is the use of ultrasound to generate highly reactive radical species through the inertial collapse of a gas/vapour cavity and is a green alternative for hydrogen production, wastewater treatment, and chemical synthesis and modifications. Yet, current sonochemical reactors often are limited by their design, resulting in low efficacy and yields with slow reaction kinetics. Here, we constructed a novel sonochemical reactor design that creates cylindrically converging ultrasound waves to create an intense localised region of high acoustic pressure amplitudes (15 MPa PKPK ) capable of spontaneously nucleating cavitation. Using a novel dosimetry technique, we determined the effect of acoustic parameters on the yield of hydroxyl radicals (HO), HO production rate, and ultimately the sonochemical efficiency (SE) of our reactor. Our reactor design had a significantly higher HO production rate and SE compared to other conventional reactors and across literature., 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 © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Characterizations based on anatomically realistic phantoms are highly effective to perform accurate technical validation of imaging systems. Specifically for photoacoustic imaging (PAI), although a variety of phantom models with simplified geometries are reported, an unmet need still exists to establish morphologically realistic heterogeneous pre-clinical phantoms. So the development of a mouse-mimicking phantom can reduce the use of animals for the validation and standardization studies of pre-clinical PAI systems and thus eventually translate the PAI technology to clinical research., Purpose: Here we designed, developed, and fabricated a stable phantom that mimics the detailed morphology of a mouse, to be used as a realistic tool for PAI., Methods: The mouse phantom, has been designed by using a combination of image modeling and 3D-printing techniques. As a tissue-mimicking material, we have used copolymer-in-oil-based material that was recently proposed by the International Photoacoustic Standardization Consortium (IPASC). In particular, the anatomically realistic phantom has been modeled by using the real atlas of a mouse as a reference. The mouse phantom includes a 3D-printed skeleton and the main abdominal organs such as the liver, spleen, and kidneys obtained by using doped copolymer-in-oil material with 3D-printed molds. In addition, the acoustic and optical properties of the tissue-mimicking material and the long-term stability have been broadly characterized., Results: Furthermore, our studies showed that the phantom is durable and stable for more than 200 days, under normal storage and repeated use. Fabrication protocol is easy to reproduce. As a result, the proposed morphologically realistic mouse phantom offers durability, material compatibility, and an unprecedented realistic resemblance to the actual rodents' anatomy in PAI., Conclusion: This durable morphologically realistic mouse phantom would minimize the animal experiments in compliance with the 3R principle of Replacement, Reduction, and Refinement. To our knowledge, this is the first time an anatomically realistic heterogeneous mouse phantom has been proposed for PAI in pre-clinical animal imaging and tested its durability over 200 days., (© 2023 American Association of Physicists in Medicine.)

We report the synthesis of hydroxyl-radical (˙OH) responsive fluorescent probes that utilise the 3,5-dihydroxybenzyl (DHB) functionality. 4-Methylumbeliferone-DHB (Umb-DHB) and resorufin-DHB (Res-DHB) in the presence of ˙OH radicals resulted in significant increases in their respective fluorescent emission intensities at 460 nm and 585 nm. The incubation of Res-DHB in HeLa cells followed by therapeutic ultrasound (1 MHz) resulted in a significant increase in fluorescence emission intensity thus permitting the ability to monitor ultrasound-induced ˙OH production in live cells.

Objective: This study aims to determine if outpatient opioid prescriptions are associated with future SUD diagnoses and overdose in injured adolescents 5 years following hospital discharge., Summary of Background Data: Approximately, 1 in 8 adolescents are diagnosed with an SUD and 1 in 10 experience an overdose in the 5 years following injury. State laws have become more restrictive on opioid prescribing by acute care providers for treating pain, however, prescriptions from other outpatient providers are still often obtained., Methods: This was a retrospective cohort study of patients ages 12-18 admitted to 2 level I trauma centers. Demographic and clinical data contained in trauma registries were linked to a regional database containing 5 years of electronic health records and prescription data. Regression models assessed whether number of outpatient opioid prescription fills after discharge at different time points in recovery were associated with a new SUD diagnosis or overdose, while controlling for demographic and injury characteristics, and depression and posttraumatic stress disorder diagnoses., Results: We linked 669 patients (90.9%) from trauma registries to a regional health information exchange database. Each prescription opioid refill in the first 3 months after discharge increased the likelihood of new SUD diagnoses by 55% (odds ratio: 1.55, confidence interval: 1.04-2.32). Odds of overdose increased with ongoing opioid use over 2-4 years post-discharge ( P = 0.016-0.025)., Conclusions: Short-term outpatient opioid prescribing over the first few months of recovery had the largest effect on developing an SUD, while long-term prescription use over multiple years was associated with a future overdose., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

For over two decades, researchers have sought to improve smallpox vaccines and also develop therapies to ensure protection against smallpox or smallpox-like disease. The 2022 human monkeypox pandemic is a reminder that these efforts should persist. Advancing such therapies have involved animal models primarily using surrogate viruses such as monkeypox virus. The intravenous monkeypox model in macaques produces a disease that is clinically similar to the lesional phase of fulminant human monkeypox or smallpox. Two criticisms of the model have been the unnatural route of virus administration and the high dose required to induce severe disease. Here, we purified monkeypox virus with the goal of lowering the challenge dose by removing cellular and viral contaminants within the inoculum. We found that there are advantages to using unpurified material for intravenous exposures.

The COVID-19 pandemic has had a staggering impact on social, economic, and public health systems worldwide. Vaccine development and mobilization against SARS-CoV-2 (the etiologic agent of COVID-19) has been rapid. However, novel strategies are still necessary to slow the pandemic, and this includes new approaches to vaccine development and/or delivery that will improve vaccination compliance and demonstrate efficacy against emerging variants. Here, we report on the immunogenicity and efficacy of a SARS-CoV-2 vaccine comprising stabilized, pre-fusion spike protein trimers displayed on a ferritin nanoparticle (SpFN) adjuvanted with either conventional aluminum hydroxide or the Army Liposomal Formulation QS-21 (ALFQ) in a cynomolgus macaque COVID-19 model. Vaccination resulted in robust cell-mediated and humoral responses and a significant reduction in lung lesions following SARS-CoV-2 infection. The strength of the immune response suggests that dose sparing through reduced or single dosing in primates may be possible with this vaccine. Overall, the data support further evaluation of SpFN as a SARS-CoV-2 protein-based vaccine candidate with attention to fractional dosing and schedule optimization.

Introduction: Orthodontic diagnosis is generally centered on the morphological aspect, as is the treatment: it is most often a matter of modifying the shape of the arches and their relationships to adjust them to a morphological norm with the goal of a beautiful smile. However legitimate it may be, this diagnostic approach may seem reductive if we consider that teeth are also used to chew: it is even their main function. But how to take into account the masticatory function?, Materials and Methods: With the help of clinical examples, the author develops the modalities of the clinical exploration of the mandibular kinematics, reflection of the mastication, on which the systemic diagnosis is based. It highlights the proprioceptive resources of the masticatory system that systemic treatment targets during the correction of malocclusions., Conclusion: The systemic diagnosis highlights the functional role of the arches, inviting, during their correction, to rehabilitate mastication in order to improve their stability.

Background: Use of routine chest x-rays (CXR) following thoracostomy tube (TT) removal is highly variable and its utility is debated. We hypothesize that routine post-pull chest x-ray (PP-CXR) findings following TT removal in pediatric trauma would not guide the decision for TT reinsertion., Methods: Patients ≤ 18 y who were not mechanically ventilated and undergoing final TT removal for a traumatic hemothorax (HTX) and/or pneumothorax (PTX) at a level I pediatric trauma center from 2010 to 2020 were retrospectively reviewed. The outcomes of interest were rate of PP-CXR and TT reinsertion rate following PP-CXR. Clinical predictors for worsened findings on PP-CXR were also assessed., Results: Fifty-nine patients were included. A CXR after TT removal was performed in 57 patients (97%), with 28% demonstrating worsened CXR findings compared to the prior film. Except for higher ISS (p = 0.033), there were no demographic or clinical predictors for worsened CXR findings. However, they were more likely to have additional films following the TT removal (p = 0.008) than those with stable or improved PP-CXR findings. One (1.8%) asymptomatic child with worsened PP-CXR findings had TT reinsertion based purely on their worsened PP-CXR findings., Conclusions: The vast majority of PP-CXR did not guide TT reinsertion after pediatric thoracic trauma. Treatment algorithms may aid to reduce variability and potentially unnecessary routine films., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The climbing fiber input to the cerebellum conveys instructive signals that can induce synaptic plasticity and learning by triggering complex spikes accompanied by large calcium transients in Purkinje cells. In the cerebellar flocculus, which supports oculomotor learning, complex spikes are driven by image motion on the retina, which could indicate an oculomotor error. In the same neurons, complex spikes also can be driven by nonvisual signals. It has been shown that the calcium transients accompanying each complex spike can vary in amplitude, even within a given cell, therefore, we compared the calcium responses associated with the visual and nonvisual inputs to floccular Purkinje cells. The calcium indicator GCaMP6f was selectively expressed in Purkinje cells, and fiber photometry was used to record the calcium responses from a population of Purkinje cells in the flocculus of awake behaving mice. During visual (optokinetic) stimuli and pairing of vestibular and visual stimuli, the calcium level increased during contraversive retinal image motion. During performance of the vestibulo-ocular reflex in the dark, calcium increased during contraversive head rotation and the associated ipsiverse eye movements. The amplitude of this nonvisual calcium response was comparable to that during conditions with retinal image motion present that induce oculomotor learning. Thus, population calcium responses of Purkinje cells in the cerebellar flocculus to visual and nonvisual input are similar to what has been reported previously for complex spikes, suggesting that multimodal instructive signals control the synaptic plasticity supporting oculomotor learning. NEW & NOTEWORTHY It was long known that the climbing fiber input to Purkinje cells in the cerebellar flocculus conveys visual feedback about the accuracy of image-stabilizing oculomotor reflexes. More recently, the same climbing fibers were reported to carry nonvisual signals. Here, we report that both visual and nonvisual inputs can elicit robust calcium responses in the Purkinje cells, suggesting that the instructive signals guiding oculomotor plasticity are multimodal.

Objectives: Injuries associated with bicycles can generally be categorized into 2 types: injuries from falling from/off bicycles and injuries from striking the bicycle. In the second mechanism category, most occur as a result of children striking their body against the bicycle handlebar. The purpose of this study was to evaluate the presentation, body location, injury severity, and need for intervention for pediatric handlebar injuries at a single level one pediatric trauma center and contrast these against other bicycle-related injuries in children., Methods: This work is a retrospective review of the trauma registry over an 8-year period. Individual charts were then reviewed for patients' demographic factors, injury details, and other clinical/radiographic findings. Each patient was then categorized as either having a handlebar versus nonhandlebar injury. Additionally, each patient's injuries were classified according to affected body "zone(s)" and the need for intervention in relation to these injuries. During the course of chart review, several unique radiographic and history/physical findings were noted and are also reported., Results: During the study period, 385 patients were identified that met study criteria. Bicycle handlebars were involved in 27.8% (107/385) of injuries and 72.2% (278/385) were nonhandlebar injuries. There were differences in injury severity score, Head Abbreviated Injury Scale, length of stay between patients with handlebar versus nonhandlebar injuries, respectively. There were also differences in incidence of injuries across most body zones between patients with handlebar versus nonhandlebar injuries. There was statistically significant difference in need for intervention for abdominal solid organ injuries among handlebar versus nonhandlebar injuries mechanisms (21.6% vs 0%; P = 0.026), respectively. Sixteen patients with a handlebar injury underwent abdominal computed tomography (CT), which found only pericolic/pelvic free fluid or were negative for any disease and had normal/mildly elevated liver function test results at the time of arrival with otherwise normal laboratory workup results. Two patients required laparotomy for bowel injury and presented with peritonitis less than 12 hours after injury. The remaining patients did not have peritonitis on examination and were discharged without operative intervention 12 to 24 hours after injury without further event., Conclusions: The bicycle handlebar is a unique mechanism of injury. The location, need for intervention, and the nature of the injury can vary significantly compared to other bicycle injuries. Handlebar injuries are more likely to cause abdominal and soft tissue injuries, whereas nonhandlebar injuries are more likely to cause extremity and skull/neck/central nervous system injuries. Because more than 20% of the reported handlebar injuries did not involve the abdomen or thoracoabdominal/extremity soft tissue as well as the variable presentation of handlebar injuries, it is imperative for the physician to consider this mechanism in all bicycle injuries. In addition, even within the same area of the body, handlebar injuries can be very different compared to nonhandlebar (i.e., orthopedic vs vascular injuries in the extremities). Physical examination and observation remain paramount when laboratory and radiographic workups are equivocal., Competing Interests: Disclosure: The authors declare conflict of interest., (Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.)

The ability to directly modify native and established biofilms has enormous potential in understanding microbial ecology and application of biofilm in 'real-world' systems. However, efficient genetic transformation of established biofilms at any scale remains challenging. In this study, we applied an ultrasound-mediated DNA delivery (UDD) technique to introduce plasmid to established non-competent biofilms in situ. Two different plasmids containing genes coding for superfolder green fluorescent protein (sfGFP) and the flavin synthesis pathway were introduced into established bacterial biofilms in microfluidic flow (transformation efficiency of 3.9 ± 0.3 × 10 -7 cells in biofilm) and microbial fuel cells (MFCs), respectively, both employing UDD. Gene expression and functional effects of genetically modified bacterial biofilms were observed, where some cells in UDD-treated Pseudomonas putida UWC1 biofilms expressed sfGFP in flow cells and UDD-treated Shewanella oneidensis MR-1 biofilms generated significantly (P < 0.05) greater (61%) bioelectricity production (21.9 ± 1.2 µA cm -2 ) in MFC than a wild-type control group (~ 13.6 ± 1.6 µA cm -2 ). The effects of UDD were amplified in subsequent growth under selection pressure due to antibiotic resistance and metabolism enhancement. UDD-induced gene transfer on biofilms grown in both microbial flow cells and MFC systems was successfully demonstrated, with working volumes of 0.16 cm 3 and 300 cm 3 , respectively, demonstrating a significant scale-up in operating volume. This is the first study to report on a potentially scalable direct genetic engineering method for established non-competent biofilms, which can be exploited in enhancing their capability towards environmental, industrial and medical applications., (© 2021 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Purpose: Traumatic abdominal wall hernia (TAWH) is a rare consequence of blunt abdominal trauma (BAT). We examined a series of patients suffering TAWH to evaluate its frequency, rate of associated concurrent intraabdominal injuries (CAI) and correlation with CT, management and outcomes., Methods: A Level 1 pediatric trauma center trauma registry was queried for children less than 18 years old suffering TAWH from BAT between 2009 and 2019., Results: 9370 patients were admitted after BAT. TAWH was observed in 11 children, at incidence 0.1%. Eight children (73%) were male, at mean age 10 years, and mean ISS of 16. Six cases (55%) were because of MVC, three (27%) impaled by a handlebar or pole, and two (18%) dragged under large machinery. Seven (64%) had a CAI requiring operative or interventional management. Patients with CAI were similar to those without other injury, with 20% and 50% CT scan sensitivity and specificity for detection of associated injury, respectively. Five patients had immediate hernia repair with laparotomy for repair of intraabdominal injury, three had delayed repair, two have asymptomatic unrepaired TAWH, and one resolved spontaneously., Conclusions: Children with TAWH have high rates of CAI requiring operative repair. CT scans have low sensitivity and specificity for detecting associated injuries. A high suspicion of injury and low threshold for exploration must be maintained in TAWH cases., Level of Evidence: IV., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Airborne transmission is predicted to be a prevalent route of human exposure with SARS-CoV-2. Aside from African green monkeys, nonhuman primate models that replicate airborne transmission of SARS-CoV-2 have not been investigated. A comparative evaluation of COVID-19 in African green monkeys, rhesus macaques, and cynomolgus macaques following airborne exposure to SARS-CoV-2 was performed to determine critical disease parameters associated with disease progression, and establish correlations between primate and human COVID-19. Respiratory abnormalities and viral shedding were noted for all animals, indicating successful infection. Cynomolgus macaques developed fever, and thrombocytopenia was measured for African green monkeys and rhesus macaques. Type II pneumocyte hyperplasia and alveolar fibrosis were more frequently observed in lung tissue from cynomolgus macaques and African green monkeys. The data indicate that, in addition to African green monkeys, macaques can be successfully infected by airborne SARS-CoV-2, providing viable macaque natural transmission models for medical countermeasure evaluation., Competing Interests: The authors have declared that no competing interests exist.

The past several years have brought revelations and paradigm shifts in research on the cerebellum. Historically viewed as a simple sensorimotor controller with homogeneous architecture, the cerebellum is increasingly implicated in cognitive functions. It possesses an impressive diversity of molecular, cellular and circuit mechanisms, embedded in a dynamic, recurrent circuit architecture. Recent insights about the diversity and dynamism of the cerebellum provide a roadmap for the next decade of cerebellar research, challenging some old concepts, reinvigorating others and defining major new research directions.

Neural circuits generate representations of the external world from multiple information streams. The navigation system provides an exceptional lens through which we may gain insights about how such computations are implemented. Neural circuits in the medial temporal lobe construct a map-like representation of space that supports navigation. This computation integrates multiple sensory cues, and, in addition, is thought to require cues related to the individual's movement through the environment. Here, we identify multiple self-motion signals, related to the position and velocity of the head and eyes, encoded by neurons in a key node of the navigation circuitry of mice, the medial entorhinal cortex (MEC). The representation of these signals is highly integrated with other cues in individual neurons. Such information could be used to compute the allocentric location of landmarks from visual cues and to generate internal representations of space.

Acoustic droplet vaporization (ADV) is an important process that enables the theragnostic application of acoustically activated droplets, where the nucleation of inertial cavitation (IC) activity must be precisely controlled. This Letter describes threshold pressure measurements for ADV and acoustic emissions consistent with IC activity of lipid-shelled non-superheated perfluoropentane nanodroplets over a range of physiologically relevant concentrations at 1.1-MHz. Under the frequency investigated, results show that the thresholds were relatively independent of concentration for intermediate concentrations (10 5 , 10 6 , and 10 7 droplets/ml), thus indicating an optimal range of droplet concentrations for conducting threshold studies. For the highest concentration, the difference between the threshold for IC and the threshold for ADV was greatly reduced, suggesting that it might prove difficult to induce ADV without concomitant IC in applications that employ higher concentrations.

The measurement of cardiac and aortic pressures enables diagnostic insight into cardiac contractility and stiffness. However, these pressures are currently assessed invasively using pressure catheters. It may be possible to estimate these pressures less invasively by applying microbubble ultrasound contrast agents as pressure sensors. The aim of this study was to investigate the subharmonic response of the microbubble ultrasound contrast agent SonoVue (Bracco Spa, Milan, Italy) at physiological pressures using a static pressure phantom. A commercially available cell culture cassette with Luer connections was used as a static pressure chamber. SonoVue was added to the phantom, and radio frequency data were recorded on the ULtrasound Advanced Open Platform (ULA-OP). The mean subharmonic amplitude over a 40% bandwidth was extracted at 0-200-mmHg hydrostatic pressures, across 1.7-7.0-MHz transmit frequencies and 3.5%-100% maximum scanner acoustic output. The Rayleigh-Plesset equation for single-bubble oscillations and additional hysteresis experiments were used to provide insight into the mechanisms underlying the subharmonic pressure response of SonoVue. The subharmonic amplitude of SonoVue increased with hydrostatic pressure up to 50 mmHg across all transmit frequencies and decreased thereafter. A decreasing microbubble surface tension may drive the initial increase in the subharmonic amplitude of SonoVue with hydrostatic pressure, while shell buckling and microbubble destruction may contribute to the subsequent decrease above 125-mmHg pressure. In conclusion, a practical operating regime that may be applied to estimate cardiac and aortic blood pressures from the subharmonic signal of SonoVue has been identified.

Objectives: Bartonella infection has been associated with endocarditis in humans, dogs, cats and cattle. In order to evaluate the importance of this pathogen as a possible source of endocarditis in United States military working dogs (MWDs), we performed a retrospective case-control study on 26 dogs with histological diagnosis of culture negative endocarditis (n = 18), endomyocarditis (n = 5) or endocardiosis (n = 3) and 28 control dogs without any histological cardiac lesions., Methods: DNA was extracted from paraffin embedded cardiac valves and tissues from case and control dogs and submitted to PCR testing with primers targeting the Bartonella gltA gene. PCR-RFLP using four restriction endonucleases and partial sequencing was then performed to determine the Bartonella species involved., Results: Nineteen (73%) cases were PCR positive for Bartonella, including B. henselae (8 dogs), B. vinsonii subsp. berkhoffii (6 dogs), B. washoensis (2 dogs) and B. elizabethae (1 dog). Only one control dog was weakly PCR positive for Bartonella. Based on the type of histological diagnosis, 13 (72.2%) dogs with endocarditis, 3 (60%) dogs with endomyocarditis and all 3 dogs with endocardiosis were Bartonella PCR positive., Conclusions: Bartonella sp. Infections were correlated with cardiopathies in US military working dogs. Systemic use of insecticides against ectoparasites and regular testing of MWDs for Bartonella infection seem highly appropriate to prevent such life-threatening exposures., Competing Interests: Conflict of Interest Statement The authors do not have any conflicts of interest to disclose., (Crown Copyright © 2019. Published by Elsevier B.V. All rights reserved.)

Recent Ebola virus (EBOV) outbreaks in West Africa and the Democratic Republic of the Congo have highlighted the urgent need for approval of medical countermeasures for treatment and prevention of EBOV disease (EVD). Until recently, when successes were achieved in characterizing the efficacy of multiple experimental EVD therapeutics in humans, the only feasible way to obtain data regarding potential clinical benefits of candidate therapeutics was by conducting well-controlled animal studies. Nonclinical studies are likely to continue to be important tools for screening and development of new candidates with improved pharmacological properties. Here, we describe a natural history study to characterize the time course and order of progression of the disease manifestations of EVD in rhesus monkeys. In 12 rhesus monkeys exposed by the intramuscular route to 1000 plaque-forming units of EBOV, multiple endpoints were monitored for 28 days following exposure. The disease progressed rapidly with mortality events occurring 7-10 days after exposure. Key disease manifestations observed consistently across the infected animals included, but were not limited to, viremia, fever, systemic inflammation, coagulopathy, lymphocytolysis, renal tubular necrosis with mineralization, and hepatocellular degeneration and necrosis.

Serotonin neurons of the dorsal and median raphe nuclei (DR, MR) collectively innervate the entire forebrain and midbrain, modulating diverse physiology and behavior. To gain a fundamental understanding of their molecular heterogeneity, we used plate-based single-cell RNA-sequencing to generate a comprehensive dataset comprising eleven transcriptomically distinct serotonin neuron clusters. Systematic in situ hybridization mapped specific clusters to the principal DR, caudal DR, or MR. These transcriptomic clusters differentially express a rich repertoire of neuropeptides, receptors, ion channels, and transcription factors. We generated novel intersectional viral-genetic tools to access specific subpopulations. Whole-brain axonal projection mapping revealed that DR serotonin neurons co-expressing vesicular glutamate transporter-3 preferentially innervate the cortex, whereas those co-expressing thyrotropin-releasing hormone innervate subcortical regions in particular the hypothalamus. Reconstruction of 50 individual DR serotonin neurons revealed diverse and segregated axonal projection patterns at the single-cell level. Together, these results provide a molecular foundation of the heterogenous serotonin neuronal phenotypes., Competing Interests: JR, AI, DF, JZ, SG, AP, GZ, SK, RW, RL, PL, AL, QL, ML, SQ, LL No competing interests declared, JR Reviewing editor, eLife, (© 2019, Ren et al.)

Purpose: Trending the pediatric-adjusted shock index (SIPA) after admission has been described for children suffering severe blunt injuries (i.e., injury severity score (ISS) ≥ 15). We propose that following SIPA in children with moderate blunt injuries, as defined by ISS 10-14, has similar utility., Methods: The trauma registry at a single institution was queried over a 7 year period. Patients were included if they were between 4 and 16 years old at the time of admission, sustained a blunt injury with an ISS 10-14, and were admitted less than 12 h after their injury (n = 501). Each patient's SIPA was then calculated at 0, 12, 24, 36, and 48 h (h) after admission and then categorized as elevated or normal at each time frame based on previously reported values. Trends in outcome variables as a function of time from admission for patients with an abnormal SIPA to normalize as well as patients with a normal admission SIPA to abnormal were analyzed., Results: In patients with a normal SIPA at arrival, elevation within the first 24 h of admission correlated with increased length of stay (LOS). Increased transfusion requirement, incidence of infectious complications, and need for in-patient rehabilitation were also seen in analyzed sub-groups. An elevated SIPA at arrival with increased length of time to normalize SIPA correlated with increased length of stay LOS in the entire cohort and in those without head injury, but not in patients with a head injury. No deaths occurred within the study cohort., Conclusions: Patients with an ISS 10-14 and a normal SIPA at time of arrival who then have an elevated SIPA in the first 24 h of admission are at increased risk for morbidity including longer LOS and infectious complications. Similarly, time to normalize an elevated admission SIPA appears to directly correlate with LOS in patients without head injuries. No correlations with markers for morbidity could be identified in patients with a head injury and an elevated SIPA at arrival. This may be due to small sample size, as there were no relations to severity of head injury as measured by head abbreviated injury scale (head AIS) and the outcome variables reported. This is an area of ongoing analysis. This study extends the previously reported utility of following SIPA after admission into milder blunt injuries.

The rate and temporal pattern of neural spiking each have the potential to influence computation. In the cerebellum, it has been hypothesized that the irregularity of interspike intervals in Purkinje cells affects their ability to transmit information to downstream neurons. Accordingly, during oculomotor behavior in mice and rhesus monkeys, mean irregularity of Purkinje cell spiking varied with mean eye velocity. However, moment-to-moment variations revealed a tight correlation between eye velocity and spike rate, with no additional information conveyed by spike irregularity. Moreover, when spike rate and irregularity were independently controlled using optogenetic stimulation, the eye movements elicited were well-described by a linear population rate code with 3-5 ms temporal precision. Biophysical and random-walk models identified biologically realistic parameter ranges that determine whether spike irregularity influences responses downstream. The results demonstrate cerebellar control of movements through a remarkably rapid rate code, with no evidence for an additional contribution of spike irregularity., Competing Interests: HP, RF, CG, TN, TM No competing interests declared, JR Reviewing editor, eLife, (© 2019, Payne et al.)

Objective: The purpose of this investigation was to determine our limb-related contemporary pediatric revascularization perioperative and follow-up outcomes after major blunt and penetrating trauma., Methods: A retrospective review was performed of a prospectively maintained pediatric trauma database spanning January 2010 to December 2017 to capture all level I trauma activations that resulted in a peripheral arterial revascularization procedure. All preoperative, intraoperative, and postoperative continuous variables are reported as a mean ± standard deviation; categorical variables are reported as a percentage of the population of interest., Results: During the study period, 1399 level I trauma activations occurred at a large-volume, urban children's hospital. The vascular surgery service was consulted in 2.6% (n = 36) of these cases for suspected vascular injury based on imaging or physical examination. Our study population included only patients who received an arterial revascularization, which was performed in 23 of the 36 consultations (1.6% of total traumas; median age, 11 years). These injuries were localized to the upper extremity in 60.9% (n = 14), lower extremity in 30.4% (n = 7), and neck in 8.7% (n = 2). The mean Injury Severity Score in the revascularized cohort was 14.0 (±7.6). Bone fractures were associated with 39.1% of the vascular injuries (90% of blunt injuries). Restoration of in-line flow was achieved by an endovascular solution in one patient and open surgery in the remainder, consisting of arterial bypass in 59.1% and direct repair in 40.9%. Within 30 days of the operation, we observed no deaths, no infections of the arterial reconstruction, and no major amputations. One patient required perioperative reintervention by the vascular team secondary to the development of a superficial seroma without evidence of graft involvement. Mean follow-up in our cohort was 43.3 (±35.4) months. During this phase, no additional deaths, amputations, chronic wounds, or limb length discrepancies were observed. All vascular repairs were patent, and all but one patient reported normal function of the affected limb at the latest clinic visit., Conclusions: Traumatic peripheral vascular injury is rare in the pediatric population but is often observed secondary to a penetrating force or after long bone fracture. However, contemporary perioperative and long-term outcomes after surgical revascularization are excellent as demonstrated in this institutional case series., (Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

As irreplaceable energy sources of minimally invasive treatment, light and sound have, separately, laid solid foundations in their clinic applications. Constrained by the relatively shallow penetration depth of light, photodynamic therapy (PDT) typically involves involves superficial targets such as shallow seated skin conditions, head and neck cancers, eye disorders, early-stage cancer of esophagus, etc. For ultrasound-driven sonodynamic therapy (SDT), however, to various organs is facilitated by the superior... transmission and focusing ability of ultrasound in biological tissues, enabling multiple therapeutic applications including treating glioma, breast cancer, hematologic tumor and opening blood-brain-barrier (BBB). Considering the emergence of theranostics and precision therapy, these two classic energy sources and corresponding sensitizers are worth reevaluating. In this review, three typical therapies using light and sound as a trigger, PDT, SDT, and combined PDT and SDT are introduced. The therapeutic dynamics and current designs of pharmacological sensitizers involved in these therapies are presented. By introducing both the history of the field and the most up-to-date design strategies, this review provides a systemic summary on the development of PDT and SDT and fosters inspiration for researchers working on 'multi-modal' therapies involving light and sound., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The optical properties of tissue change during thermal ablation. Multi-modal methods such as acousto-optic (AO) and photo-acoustic (PA) imaging may provide a real-time, direct measure of lesion formation. Baseline changes in optical properties have been previously measured over limited ranges of thermal dose for tissues exposed to a temperature-controlled water bath, however, there is scant data for optical properties of lesions created by HIFU. In this work, the optical scattering and absorption coefficients from 400-1300 nm of excised chicken breast exposed to HIFU were measured using an integrating sphere spectrophotometric technique. HIFU-induced spatiotemporal temperature elevations were measured using an infrared camera and used to calculate the thermal dose delivered to a localized region of tissue. Results obtained over a range of thermal dose spanning 9 orders of magnitude show that the reduced scattering coefficient increases for HIFU exposures exceeding a threshold thermal dose of CEM 43   =  600  ±  81 cumulative equivalent minutes. HIFU-induced thermal damage results in changes in scattering over all optical wavelengths, with a 2.5-fold increase for thermal lesions exceeding 70 °C. The tissue absorption coefficient was also found to increase for thermally lesioned tissue, however, the magnitude was strongly dependent on the optical wavelength and there was substantial sample-to-sample variability, such that the existence of a threshold thermal dose could not be determined. Therapeutic windows, where the optical penetration depth is expected to be greatest, were identified in the near infrared regime centered near 900 nm and 1100 nm. These data motivate further research to improve the real-time AO and PA sensing of lesion formation during HIFU therapy as an alternative to thermometry.

Climbing fiber-driven long-term depression (LTD) of parallel fiber synapses onto cerebellar Purkinje cells has long been investigated as a putative mechanism of motor learning. We recently discovered that the rules governing the induction of LTD at these synapses vary across different regions of the cerebellum. Here, we discuss the design of LTD induction protocols in light of this heterogeneity in plasticity rules. The analytical advantages of the cerebellum provide an opportunity to develop a deeper understanding of how the specific plasticity rules at synapses support the implementation of learning.

Supervised learning plays a key role in the operation of many biological and artificial neural networks. Analysis of the computations underlying supervised learning is facilitated by the relatively simple and uniform architecture of the cerebellum, a brain area that supports numerous motor, sensory, and cognitive functions. We highlight recent discoveries indicating that the cerebellum implements supervised learning using the following organizational principles: ( a) extensive preprocessing of input representations (i.e., feature engineering), ( b) massively recurrent circuit architecture, ( c) linear input-output computations, ( d) sophisticated instructive signals that can be regulated and are predictive, ( e) adaptive mechanisms of plasticity with multiple timescales, and ( f) task-specific hardware specializations. The principles emerging from studies of the cerebellum have striking parallels with those in other brain areas and in artificial neural networks, as well as some notable differences, which can inform future research on supervised learning and inspire next-generation machine-based algorithms.

Purpose: The utility of measuring the pediatric adjusted shock index (SIPA) at admission for predicting severity of blunt injury in pediatric patients has been previously reported. However, the utility of following SIPA after admission is not well described., Methods: The trauma registry from a level-one pediatric trauma center was queried from January 1, 2010 to December 31, 2015. Patients were included if they were between 4 and 16years old at the time of admission, sustained a blunt injury with an Injury Severity Score≥15, and were admitted less than 12h after their injury (n=286). Each patient's SIPA was then calculated at 0, 12, 24, 36, and 48h after admission and then categorized as elevated or normal at each time frame based upon previously reported values. Trends in outcome variables as a function of time from admission for patients with an abnormal SIPA to normalize as well as patients with a normal admission SIPA to abnormal were analyzed., Results: In patients with a normal SIPA at arrival, 18.4% of patients who developed an elevated SIPA at 12h after admission died, whereas 2.4% of patients who maintained a normal SIPA throughout the first 48h of admission died (p<0.01). Among patients with an elevated SIPA at arrival, increased length of time to normalize SIPA correlated with increased length of stay (LOS) and intensive care unit (ICU) LOS. Similarly, elevation of SIPA after arrival in patients with a normal initial SIPA correlated to increased LOS and ICU LOS., Conclusions: Patients with a normal SIPA at time of arrival who then have an elevated SIPA in the first 24h of admission are at increased risk for morbidity and mortality compared to those whose SIPA remains normal throughout the first 48h of admission. Similarly, time to normalize an elevated admission SIPA appears to directly correlate with LOS, ICU LOS, and other markers of morbidity across a mixed blunt trauma population. Whether trending SIPA early in the hospital course serves only as a marker for injury severity or if it has utility as a resuscitation metric has not yet been determined., Type of Study: Prognostic., Level of Evidence: Level II., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Physical characterization of an ultrasound contrast agent (UCA) aids in its safe and effective use in diagnostic and therapeutic applications. The goal of this study was to investigate the impact of temperature on the size distribution, shell properties, and stability of Definity ® , a U.S. Food and Drug Administration-approved UCA used for left ventricular opacification. A Coulter counter was modified to enable particle size measurements at physiologic temperatures. The broadband acoustic attenuation spectrum and size distribution of Definity ® were measured at room temperature (25 °C) and physiologic temperature (37 °C) and were used to estimate the viscoelastic shell properties of the agent at both temperatures. Attenuation and size distribution was measured over time to assess the effect of temperature on the temporal stability of Definity ® . The attenuation coefficient of Definity ® at 37 °C was as much as 5 dB higher than the attenuation coefficient measured at 25 °C. However, the size distributions of Definity ® at 25 °C and 37 °C were similar. The estimated shell stiffness and viscosity decreased from 1.76 ± 0.18 N/m and 0.21 × 10 -6  ± 0.07 × 10 -6 kg/s at 25 °C to 1.01 ± 0.07 N/m and 0.04 × 10 -6  ± 0.04 × 10 -6 kg/s at 37 °C, respectively. Size-dependent differences in dissolution rates were observed within the UCA population at both 25 °C and 37 °C. Additionally, cooling the diluted UCA suspension from 37 °C to 25 °C accelerated the dissolution rate. These results indicate that although temperature affects the shell properties of Definity ® and can influence the stability of Definity ® , the size distribution of this agent is not affected by a temperature increase from 25 °C to 37 °C., (Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.)

Eye movements provide insights about a wide range of brain functions, from sensorimotor integration to cognition; hence, the measurement of eye movements is an important tool in neuroscience research. We describe a method, based on magnetic sensing, for measuring eye movements in head-fixed and freely moving mice. A small magnet was surgically implanted on the eye, and changes in the magnet angle as the eye rotated were detected by a magnetic field sensor. Systematic testing demonstrated high resolution measurements of eye position of <0.1°. Magnetic eye tracking offers several advantages over the well-established eye coil and video-oculography methods. Most notably, it provides the first method for reliable, high-resolution measurement of eye movements in freely moving mice, revealing increased eye movements and altered binocular coordination compared to head-fixed mice. Overall, magnetic eye tracking provides a lightweight, inexpensive, easily implemented, and high-resolution method suitable for a wide range of applications.