Divergent input patterns to the central lateral amygdala play a duet in fear memory formation.

Somatostatin (SOM)-expressing neurons in the central lateral amygdala (CeL) are responsible for fear memory learning, but the circuit and molecular mechanisms underlying this biology remain elusive. Here, we found that glutamatergic neurons in the lateral parabrachial nucleus (LPB) directly dominated the activity of CeL neurons, and that selectively inhibiting the LPB→CeL pathway suppressed fear memory acquisition. By contrast, inhibiting CeL-projecting glutamatergic neurons in the paraventricular thalamic nucleus (PVT) interfered with consolidation-related processes.

Effect of Nano-Sized Energetic Materials (nEMs) on the Performance of Solid Propellants: A Review.

As a hot research topic, nano-scale energetic materials have recently attracted much attention in the fields of propellants and explosives. The preparation of different types of nano-sized energetic materials were carried out, and the effects of nano-sized energetic materials (nEMs) on the properties of solid propellants and explosives were investigated and compared with those of micro-sized ones, placing emphasis on the investigation of the hazardous properties, which could be useable for solid rocket nozzle motor applications. It was found that the nano-sized energetic materials can decrease the impact sensitivity and friction sensitivity of solid propellants and explosives compared with the corresponding micro-sized ones, and the mechanical sensitivities are lower than that of micro-sized particles formulation.

Effect of Metal Nanopowders on the Performance of Solid Rocket Propellants: A Review.

The effects of different types of nano-sized metal particles, such as aluminum (nAl), zirconium (nZr), titanium (nTi), and nickel (nNi), on the properties of a variety of solid rocket propellants (composite, fuel-rich, and composite modified double base (CMDB)) were analyzed and compared with those of propellants loaded with micro-sized Al (mAl) powder. Emphasis was placed on the investigation of burning rate, pressure exponent (), and hazardous properties, which control whether a propellant can be adopted in solid rocket motors. It was found that nano-sized additives can affect the combustion behavior and increase the burning rate of propellants.

Investigation of a Low-Toxicity Energetic Binder for a Solid Propellant: Curing, Microstructures, and Performance.

In this work, a promising propellant binder using the energetic branched glycidyl azide polymer (B-GAP) as a matrix and the low-toxic dimer acid diisocyanate (DDI) as a curing agent was prepared, under the catalysis of dibutyl tin dilaurate. The curing kinetics considering the thermal diffusion effect and the reaction endpoint of B-GAP/DDI were investigated by the thermal analysis method and a newly proposed variance method, respectively. Moreover, the buildup of microstructures during curing and the tensile and dynamic mechanical performance of this binder were respectively explored.

Molecular dynamic simulation of performance of modified BAMO/AMMO copolymers and their effects on mechanical properties of energetic materials.

Based on molecular dynamic method, densities, mechanical behavior and mechanical performance of P(BAMO/ AMMO) (Polymer 1) and two novel modified P(BAMO/AMMO) (Polymer 2: containing amino group, Polymer 3: containing nitro group), and their effects on mechanical properties of four energetic materials are investigated, the main results are as follow: Polymer 2 (1.235 g/cm, 240 ± 5 K) and Polymer 3: 1.281 g/cm, 181 ± 3 K) possess higher densities and lower glass transition temperatures than Polymer 1 (1.

Al-Based Nano-Sized Composite Energetic Materials (Nano-CEMs): Preparation, Characterization, and Performance.

As one of the new types of functional materials, nano-sized composite energetic materials (nano-CEMs) possess many advantages and broad application prospects in the research field of explosives and propellants. The recent progress in the preparation and performance characterization of Al-based nano-CEMs has been reviewed. The preparation methods and properties of Al-based nano-CEMs are emphatically analyzed.

A pilot study in men to show the effects of postural fluid shifts on the severity of obstructive sleep apnea.

Purpose: Studies reveal that rostral fluid shifts due to body posture changes from standing to lying down may narrow the upper airway. However, without credible and direct experimental evidence, it remains unclear what the role of natural fluid redistribution in the neck is in affecting obstructive sleep apnea (OSA) severity. Our aim is using direct experimental evidence to determine whether or not postural fluid shifts affect OSA severity.