Quadrupolar Resonance Spectroscopy of Individual Nuclei Using a Room-Temperature Quantum Sensor.

Nuclear quadrupolar resonance (NQR) spectroscopy reveals chemical bonding patterns in materials and molecules through the unique coupling between nuclear spins and local fields. However, traditional NQR techniques require macroscopic ensembles of nuclei to yield a detectable signal, which obscures molecule-to-molecule variations. Solid-state spin qubits, such as the nitrogen-vacancy (NV) center in diamond, facilitate the detection and control of individual nuclei through their local magnetic couplings.

Breaking reflection symmetry: evolving long dynamical cycles in Boolean systems.

In interacting dynamical systems, specific local interaction rules for system components give rise to diverse and complex global dynamics. Long dynamical cycles are a key feature of many natural interacting systems, especially in biology. Examples of dynamical cycles range from circadian rhythms regulating sleep to cell cycles regulating reproductive behavior.

Myelination and excitation-inhibition balance synergistically shape structure-function coupling across the human cortex.

Recent work has demonstrated that the relationship between structural and functional connectivity varies regionally across the human brain, with reduced coupling emerging along the sensory-association cortical hierarchy. The biological underpinnings driving this expression, however, remain largely unknown. Here, we postulate that intracortical myelination and excitation-inhibition (EI) balance mediate the heterogeneous expression of structure-function coupling (SFC) and its temporal variance across the cortical hierarchy.

Asymmetric signaling across the hierarchy of cytoarchitecture within the human connectome.

Cortical variations in cytoarchitecture form a sensory-fugal axis that shapes regional profiles of extrinsic connectivity and is thought to guide signal propagation and integration across the cortical hierarchy. While neuroimaging work has shown that this axis constrains local properties of the human connectome, it remains unclear whether it also shapes the asymmetric signaling that arises from higher-order topology. Here, we used network control theory to examine the amount of energy required to propagate dynamics across the sensory-fugal axis.

A new automated tool to quantify nucleoid distribution within mitochondrial networks.

Mitochondrial DNA (mtDNA) maintenance is essential to sustain a functionally healthy population of mitochondria within cells. Proper mtDNA replication and distribution within mitochondrial networks are essential to maintain mitochondrial homeostasis. However, the fundamental basis of mtDNA segregation and distribution within mitochondrial networks is still unclear.

Mitochondrial adaptation in human mesenchymal stem cells following ionizing radiation.

Mitochondria are highly dynamic organelles that respond rapidly to a number of stressors to regulate energy transduction, cell death signaling, and reactive oxygen species generation. We hypothesized that mitochondrial remodeling, comprising both structural and functional alterations, following ionizing radiation (IR) may underlie some of the tenets of radiobiology. Mesenchymal stem cells (MSCs) are precursors of bone marrow stroma and are altered in acute myeloid leukemia and by radiation and chemotherapy.

A novel algorithm identifies stress-induced alterations in mitochondrial connectivity and inner membrane structure from confocal images.

Mitochondria exist as a highly interconnected network that is exquisitely sensitive to variations in nutrient availability, as well as a large array of cellular stresses. Changes in length and connectivity of this network, as well as alterations in the mitochondrial inner membrane (cristae), regulate cell fate by controlling metabolism, proliferation, differentiation, and cell death. Given the key roles of mitochondrial dynamics, the process by which mitochondria constantly fuse and fragment, the measure of mitochondrial length and connectivity provides crucial information on the health and activity of various cell populations.

Noninvasive correction of a fractured endoluminal nitinol tracheal stent in a dog.

An 11-year-old, castrated male Pomeranian was presented for intractable cough and dyspnea secondary to severe tracheal collapse. An endoluminal nitinol tracheal stent was placed with good results. Five months following placement of the prosthesis, clinical signs acutely recurred and failure of the implant was noted.

Mucoadhesive properties of cross-linked high amylose starch derivatives.

Acetate (Ac-), aminoethyl (AE-) and carboxymethyl (CM-)derivatives of cross-linked high amylose starch (HASCL-6) were previously shown to control, over more than 20h, the release of drugs from highly loaded (up to 60% drug) monolithic tablets. It was now of interest to evaluate their mucoadhesive characteristics in view of further utilization in buccal or vaginal transmucosal delivery. The present study shows that ionic AE-HASCL-6 and CM-HASCL-6 derivatives exhibit higher mucoadhesive properties than neutral HASCL-6 and Ac-HASCL-6, suggesting that the ionic groups introduced on cross-linked starch chains play a role in the bioadhesion process.

Taurine-deficient dilated cardiomyopathy in a family of golden retrievers.

A reversible taurine-deficient dilated cardiomyopathy occurred in five related golden retrievers. An apical systolic heart murmur was the most common physical abnormality. According to fractional shortening and end-systolic diameter on echocardiography, significant improvements (P<0.