Water state, thermal transition behavior and structure of hydrated gelatin films.

The state of water, thermal transition behaviors, molecular interactions, crystalline structure, and mechanical performance of hydrated gelatin films were studied by differential scanning calorimetry (DSC), infrared spectroscopy (FTIR), X-ray diffraction, and universal testing instruments. The DSC results showed that with increase of the water content, two types of water, including unfreezable bound water and freezable water, appeared in turn. Below a critical water content of 30%, the glass transition temperature (Tg) of the hydrated gelatin films decreased notably with an increase in water content, which leveled off at water content higher than this threshold. This observation suggests that only the unfreezable water exhibits a plasticizing effect. In addition, the melting temperature (Tm) of hydrated gelatin films decreased continuously with an increase in water content, whereas the melting enthalpy showed a non-monotonic dependence on hydration level. Structural analysis showed that at medium hydration levels up to 13.4% water content, the unfreezable water facilitated the formation of additional triple helices, confirmed by DSC results. Spectral data revealed that the -OH groups of unfreezable water molecules interacted with the -NH groups of the protein via hydrogen bonds. Moreover, the mechanical properties of the hydrated gelatin films were sensitive to their hydration level, and the tensile strength was dominated by the helix content of the protein films. These results show the feasibility of using hydration to regulate the microstructure and properties of biopolymers.

Structure and properties of citric acid cross-linked chitosan/poly(vinyl alcohol) composite films for food packaging applications.

In this study, the composite films of poly(vinyl alcohol) and citric acid cross-linked chitosan were prepared, and the effect of mass ratio on their structure and properties was investigated in detail. Chitosan was cross-linked by citric acid via an amidation reaction at an elevated temperature, which was confirmed by infrared spectra and X-ray photoelectron spectra. Chitosan is miscible with PVA due to the formation of strong hydrogen bonds between them. Among these composite films, 1:1 CS/PVA film showed excellent mechanical properties, good creep resistance, and shape recovery ability, attributing to its high crosslinking degree. In addition, this film possessed hydrophobicity, excellent self-adhesion property, and the lowest WVP, and it was successfully used as a packaging material for cherry. These observations indicate that the cooperative effects of crosslinking and hydrogen bonds control the structure and properties of chitosan/PVA composite film, which is a very potential material for food packaging and preservation.

Dysfunction of cortical GABAergic neurons leads to sensory hyper-reactivity in a Shank3 mouse model of ASD.

Hyper-reactivity to sensory input is a common and debilitating symptom in individuals with autism spectrum disorders (ASD), but the neural basis underlying sensory abnormality is not completely understood. Here we examined the neural representations of sensory perception in the neocortex of a Shank3B-/- mouse model of ASD. Male and female Shank3B-/- mice were more sensitive to relatively weak tactile stimulation in a vibrissa motion detection task. In vivo population calcium imaging in vibrissa primary somatosensory cortex (vS1) revealed increased spontaneous and stimulus-evoked firing in pyramidal neurons but reduced activity in interneurons. Preferential deletion of Shank3 in vS1 inhibitory interneurons led to pyramidal neuron hyperactivity and increased stimulus sensitivity in the vibrissa motion detection task. These findings provide evidence that cortical GABAergic interneuron dysfunction plays a key role in sensory hyper-reactivity in a Shank3 mouse model of ASD and identify a potential cellular target for exploring therapeutic interventions.

Improved Socio-Emotional and Behavioral Functioning in Students with Autism Following School-Based Smartglasses Intervention: Multi-Stage Feasibility and Controlled Efficacy Study.

Background: Students with Autism Spectrum Disorder (ASD) commonly demonstrate prominent social communication deficits, symptoms of attention-deficit/hyperactivity disorder, and chronic irritability. These challenges hinder academic progress and frequently persist despite educational, behavioral, and medical interventions. An assistive smartglasses technology may aid these individuals, especially if the technology is efficacious in ecologically-valid school settings. This study explored the feasibility and efficacy of Empowered Brain, a computerized smartglasses intervention designed as a socio-emotional behavioral aid for students with ASD. Methods: This two-part six-week study involved four school children with ASD from a public elementary school. The study incorporated an initial three-week feasibility stage followed by a three-week controlled longitudinal efficacy stage. Both stages involved the use of a twice-daily socio-emotional intervention with the smartglasses. Educators completed pre-intervention and post-intervention Aberrant Behavioral Checklist (ABC) ratings at the start of the feasibility stage, and weekly during the efficacy stage. Primary outcome measures were improvements in the ABC subscales of irritability, hyperactivity, and social withdrawal. Results: Students in both feasibility and efficacy stages demonstrated improvements (decreases) in irritability, hyperactivity, and social withdrawal compared to a baseline period and control periods, respectively. Participants in the controlled efficacy stage demonstrated decreased ABC subscale scores of 90% for irritability, 41.6% for hyperactivity, and 45.6% for social withdrawal. An intervention exposure-response improvement in irritability and hyperactivity was found during the efficacy stage. Educators rated the technology as superior or vastly superior compared to other assistive technologies. Conclusion: A substantial number of school children with ASD demonstrate chronic and impairing cognitive and behavioral challenges. This study provides evidence that Empowered Brain, a smartglasses-based socio-emotional aid for autism, is both feasible and efficacious in improving symptoms of social withdrawal, irritability, and hyperactivity in students with autism. The improvement is demonstrated as part of a longitudinal school-based intervention. Further studies involving larger samples and incorporation of randomized controlled trial methodology are underway to further elucidate the impact of this technology.

Feasibility of an Autism-Focused Augmented Reality Smartglasses System for Social Communication and Behavioral Coaching.

BACKGROUND: Autism spectrum disorder (ASD) is a childhood-onset neurodevelopmental disorder with a rapidly rising prevalence, currently affecting 1 in 68 children, and over 3.5 million people in the United States. Current ASD interventions are primarily based on in-person behavioral therapies that are both costly and difficult to access. These interventions aim to address some of the fundamental deficits that clinically characterize ASD, including deficits in social communication, and the presence of stereotypies, and other autism-related behaviors. Current diagnostic and therapeutic approaches seldom rely on quantitative data measures of symptomatology, severity, or condition trajectory. METHODS: Given the current situation, we report on the Brain Power System (BPS), a digital behavioral aid with quantitative data gathering and reporting features. The BPS includes customized smartglasses, providing targeted personalized coaching experiences through a family of gamified augmented-reality applications utilizing artificial intelligence. These applications provide children and adults with coaching for emotion recognition, face directed gaze, eye contact, and behavioral self-regulation. This preliminary case report, part of a larger set of upcoming research reports, explores the feasibility of the BPS to provide coaching in two boys with clinically diagnosed ASD, aged 8 and 9 years. RESULTS: The coaching intervention was found to be well tolerated and rated as being both engaging and fun. Both males could easily use the system, and no technical problems were noted. During the intervention, caregivers reported improved non-verbal communication, eye contact, and social engagement during the intervention. Both boys demonstrated decreased symptoms of ASD, as measured by the aberrant behavior checklist at 24-h post-intervention. Specifically, both cases demonstrated improvements in irritability, lethargy, stereotypy, hyperactivity/non-compliance, and inappropriate speech. CONCLUSION: Smartglasses using augmented reality may have an important future role in helping address the therapeutic needs of children with ASD. Quantitative data gathering from such sensor-rich systems may allow for digital phenotyping and the refinement of social communication constructs of the research domain criteria. This report provides evidence for the feasibility, usability, and tolerability of one such specialized smartglasses system.

A viral strategy for targeting and manipulating interneurons across vertebrate species.

A fundamental impediment to understanding the brain is the availability of inexpensive and robust methods for targeting and manipulating specific neuronal populations. The need to overcome this barrier is pressing because there are considerable anatomical, physiological, cognitive and behavioral differences between mice and higher mammalian species in which it is difficult to specifically target and manipulate genetically defined functional cell types. In particular, it is unclear the degree to which insights from mouse models can shed light on the neural mechanisms that mediate cognitive functions in higher species, including humans. Here we describe a novel recombinant adeno-associated virus that restricts gene expression to GABAergic interneurons within the telencephalon. We demonstrate that the viral expression is specific and robust, allowing for morphological visualization, activity monitoring and functional manipulation of interneurons in both mice and non-genetically tractable species, thus opening the possibility to study GABAergic function in virtually any vertebrate species.