Delamination Detection and Localization in Vibrating Composite Plates and Shells Using the Inverse Finite Element Method.

Delamination damage is one of the most critical damage modes of composite materials. It takes place through the thickness of the laminated composites and does not show subtle surface effects. In the present study, a delamination detection approach based on equivalent von Mises strains is demonstrated for vibrating laminated (i.

NAD metabolism drives astrocyte proinflammatory reprogramming in central nervous system autoimmunity.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). Astrocytes are the most abundant glial cells in the CNS, and their dysfunction contributes to the pathogenesis of MS and its animal model, experimental autoimmune encephalomyelitis (EAE). Recent advances highlight the pivotal role of cellular metabolism in programming immune responses.

Astrocyte immunometabolic regulation of the tumour microenvironment drives glioblastoma pathogenicity.

Malignant brain tumours are the cause of a disproportionate level of morbidity and mortality among cancer patients, an unfortunate statistic that has remained constant for decades. Despite considerable advances in the molecular characterization of these tumours, targeting the cancer cells has yet to produce significant advances in treatment. An alternative strategy is to target cells in the glioblastoma microenvironment, such as tumour-associated astrocytes.

Shape Sensing of Plate Structures Using the Inverse Finite Element Method: Investigation of Efficient Strain-Sensor Patterns.

Methods for real-time reconstruction of structural displacements using measured strain data is an area of active research due to its potential application for Structural Health Monitoring (SHM) and morphing structure control. The inverse Finite Element Method (iFEM) has been shown to be well suited for the full-field reconstruction of displacements, strains, and stresses of structures instrumented with discrete or continuous strain sensors. In practical applications, where the available number of sensors may be limited, the number and sensor positions constitute the key parameters.

Application of Inverse Finite Element Method to Shape Sensing of Curved Beams.

Curved beam, plate, and shell finite elements are commonly used in the finite element modeling of a wide range of civil and mechanical engineering structures. In civil engineering, curved elements are used to model tunnels, arch bridges, pipelines, and domes. Such structures provide a more efficient load transfer than their straight/flat counterparts due to the additional strength provided by their curved geometry.

An exploratory study of illegal gamblers in Hong Kong.

This study investigates the nature and behaviour of illegal gamblers in Hong Kong. A face-to-face street survey of 512 gamblers was conducted in Hong Kong between September and December 2015 with supplementary convenience sampling allowing for analysis of a total sample of 103 illegal gamblers. 56% of illegal gamblers recorded results consistent with this study's definition of 'excessive gambling' [i.

Computationally efficient beam elements for accurate stresses in sandwich laminates and laminated composites with delaminations.

Laminated composites are prone to delamination failure due to the lack of reinforcement through the thickness. Therefore, during the design process the initiation and propagation of delaminations should be accounted for as early as possible. This paper presents computationally efficient nine degree-of-freedom (dof) and eight-dof shear locking-free beam elements using the mixed form of the refined zigzag theory (RZT).

Sensory Axon Regeneration: A Review from an in vivo Imaging Perspective.

Injured primary sensory axons fail to regenerate into the spinal cord, leading to chronic pain and permanent sensory loss. Re-entry is prevented at the dorsal root entry zone (DREZ), the CNS-PNS interface. Why axons stop or turn around at the DREZ has generally been attributed to growth-repellent molecules associated with astrocytes and oligodendrocytes/myelin.

The suffering is similar--is the treatment equal? An intervention with Arab Terror injured.

In the course of the last Intifada and during the Second Lebanon War, all citizens of Israel were exposed to waves of terrorism that claimed many people wounded and killed, unrelated to religious differences, age, gender, or nationality: Jews and Arabs suffered alike. The acts of terror exposed all inhabitants equally to injury, suffering, and the need to adjust. The professional literature attests that minority groups are at a higher risk of experiencing post-traumatic symptoms as a result of exposure to acts of terror.

Morphometric analysis of craniofacial features in mono- and dizygotic twins discordant for unilateral cleft lip and palate.

Objective: To compare craniofacial differences between twins discordant for surgically repaired unilateral cleft lip and palate (CLP) during the developmental ages and to test the effect of zygosity on the shape and size of the craniofacial skeleton of the same twins by means of thin plate spline (TPS) analysis.

Materials And Methods: Lateral and posteroanterior (PA) cephalometric films from 19 sets of monozygotic (MZ) twins (15 male and 4 female) and 10 dizygotic (DZ) twins (7 male and 3 female) were analyzed. TPS analysis evaluated statistically significant differences in the craniofacial shape and size between affected and unaffected twins within MZ and DZ twin couples.

In vivo imaging of dorsal root regeneration: rapid immobilization and presynaptic differentiation at the CNS/PNS border.

Dorsal root (DR) axons regenerate in the PNS but turn around or stop at the dorsal root entry zone (DREZ), the entrance into the CNS. Earlier studies that relied on conventional tracing techniques or postmortem analyses attributed the regeneration failure to growth inhibitors and lack of intrinsic growth potential. Here, we report the first in vivo imaging study of DR regeneration.

Concussive brain trauma in the mouse results in acute cognitive deficits and sustained impairment of axonal function.

Concussive brain injury (CBI) accounts for approximately 75% of all brain-injured people in the United States each year and is particularly prevalent in contact sports. Concussion is the mildest form of diffuse traumatic brain injury (TBI) and results in transient cognitive dysfunction, the neuropathologic basis for which is traumatic axonal injury (TAI). To evaluate the structural and functional changes associated with concussion-induced cognitive deficits, adult mice were subjected to an impact on the intact skull over the midline suture that resulted in a brief apneic period and loss of the righting reflex.

Pathology of blast-related brain injury.

Blasts are responsible for about two-thirds of the combat injuries in Operation Iraqi Freedom and Operation Enduring Freedom, which include at least 1,200 traumatic brain injuries. Blasts inflict damage to the brain directly and by causing injuries to other organs, resulting in air emboli, hypoxia, and shock. Direct injuries to the brain result from rapid shifts in air pressure (primary blast injury), from impacts with munitions fragments and other objects propelled by the explosion (secondary blast injury), and from collisions with objects and rapid acceleration of individuals propelled by the explosion (tertiary blast injury).

Distinct muscarinic acetylcholine receptor subtypes contribute to stability and growth, but not compensatory plasticity, of neuromuscular synapses.

Muscarinic acetylcholine receptors (mAChRs) modulate synaptic function, but whether they influence synaptic structure remains unknown. At neuromuscular junctions (NMJs), mAChRs have been implicated in compensatory sprouting of axon terminals in paralyzed or denervated muscles. Here we used pharmacological and genetic inhibition and localization studies of mAChR subtypes at mouse NMJs to demonstrate their roles in synaptic stability and growth but not in compensatory sprouting.

Neuromuscular transmission failure and muscle fatigue in ankle muscles of the adult rat after spinal cord injury.

Current evidence suggests that significant morphological changes occur in nerve-muscle connections caudal to spinal cord injury (SCI). To determine whether neuromuscular junction (NMJ) function is compromised after SCI, we investigated the contribution of NMJ failure to hindlimb muscle fatigue in control and spinalized adult rats. Repetitive supramaximal nerve stimulation was applied to two muscle-nerve preparations: medial gastrocnemius (MG)-tibial and tibialis anterior (TA)-peroneal.

An ongoing, multi-faceted program for victims of terror attacks and their families.

Victims of terror attacks, whether or not physically injured, sometimes suffer long-term posttraumatic symptoms, although the intensity of symptoms differs among individuals. Often, after discharge from the hospital, additional posttraumatic symptoms and emotional distress are evident, together with difficulty in readjusting to a normal life. This paper describes an ongoing multi-faceted program to empower victims and their families and assist them on the journey to recovery.

Fibrillation potentials following spinal cord injury: improvement with neurotrophins and exercise.

Fibrillation potentials and positive sharp waves (spontaneous potentials) are the electrophysiological hallmark of denervated skeletal muscle, and their detection by intramuscular electromyography (EMG) is the clinical gold standard for diagnosing denervated skeletal muscle. Surprisingly, spontaneous potentials have been described following human and experimental spinal cord injury (SCI) in muscles innervated by spinal cord segments distal to the level of direct spinal injury. To determine whether electrophysiological abnormalities are improved by two therapeutic interventions for experimental SCI, neurotrophic factors and exercise training, we studied four representative hindlimb muscles in adult domestic short-hair cats following complete transection of the spinal cord at T11-T12.

Paralysis elicited by spinal cord injury evokes selective disassembly of neuromuscular synapses with and without terminal sprouting in ankle flexors of the adult rat.

Neuromuscular junctions (NMJs) innervated by motor neurons below spinal cord injury (SCI) have been reported to remain intact despite the interruption of supraspinal pathways and the resultant loss of activity. Here we report notably heterogeneous NMJ responses to SCI that include overt synapse disassembly. Complete transection of the thoracic spinal cord of adult rats evoked massive sprouting of nerve terminals in a subset of NMJs in ankle flexors, extensor digitorum longus, and tibialis anterior.

Neural stem cells may be uniquely suited for combined gene therapy and cell replacement: Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury.

Previously, we reported that, when clonal neural stem cells (NSCs) were transplanted into brains of postnatal mice subjected to unilateral hypoxic-ischemic (HI) injury (optimally 3-7 days following infarction), donor-derived cells homed preferentially (from even distant locations) to and integrated extensively within the large ischemic areas that spanned the hemisphere. A subpopulation of NSCs and host cells, particularly in the penumbra, "shifted" their differentiation towards neurons and oligodendrocytes, the cell types typically damaged following asphyxia and least likely to regenerate spontaneously and in sufficient quantity in the "post-developmental" CNS. That no neurons and few oligodendrocytes were generated from the NSCs in intact postnatal cortex suggested that novel signals are transiently elaborated following HI to which NSCs might respond.

Immunosuppression with either cyclosporine a or FK506 supports survival of transplanted fibroblasts and promotes growth of host axons into the transplant after spinal cord injury.

Fibroblasts that have been genetically modified to secrete neurotrophins can stimulate axonal regeneration, rescue injured neurons, and improve function when grafted into a spinal cord injury site. These grafts are usually allografts that require immunosuppression to prevent rejection. In this study, we compared the effects of two immunophilin-ligands (cyclosporine A [CsA] and FK506) that are used clinically to prevent transplant rejection on protection of grafted fibroblasts.

Fate of immortalized human neuronal progenitor cells transplanted in rat spinal cord.

Background: Replacement of neurons and glia by transplantation has been proposed as a therapy for neurodegenerative diseases, including amyotrophic lateral sclerosis. This strategy requires using human motor neuronal progenitor cells or xenografts of animal cells, but there is little evidence that xenografted neuronal cells can survive in spinal cord despite immunosuppression.

Objective: To clarify the mechanisms responsible for the death of xenografted neurons in spinal cord.

Ex vivo evaluation of ADC values within spinal cord white matter tracts.

Background And Purpose: Our purpose was to evaluate the effect of fixative on apparent diffusion coefficient (ADC) values and anisotropy within spinal cord white matter. As glutaraldehyde (GL) better preserves axonal ultrastructure as compared with paraformaldehyde (PF), we hypothesize that spinal cord white matter fixed with GL will have increased anisotropic water diffusion as compared with specimens fixed with PF.

Methods: Eleven rats were perfusion-fixed with either 4% PF or a combination of 2.

Alginate encapsulated BDNF-producing fibroblast grafts permit recovery of function after spinal cord injury in the absence of immune suppression.

Encapsulation of cells has the potential to provide a protective barrier against host immune cell interactions after grafting. Previously we have shown that alginate encapsulated BDNF-producing fibroblasts (Fb/BDNF) survived for one month in culture, made bioactive neurotrophins, survived transplantation into the injured spinal cord in the absence of immune suppression, and provided a permissive environment for host axon growth. We extend these studies by examining the effects of grafting encapsulated Fb/BDNF into a subtotal cervical hemisection on recovery of forelimb and hindlimb function and axonal growth in the absence of immune suppression.

Apparent diffusion coefficients in spinal cord transplants and surrounding white matter correlate with degree of axonal dieback after injury in rats.

Background And Purpose: Abnormal apparent diffusion coefficient (ADC) values in injured spinal cord white matter and fibroblast transplants have been shown to correspond with qualitative histologic findings of axonal loss or regeneration. We proposed that ADC values would correlate with quantitative axonal tracing in the transected rubrospinal tract (RST).

Methods: Eleven rats received right-sided lateral funiculus lesions at C3-4 (disrupting the RST) and transplantation of fibroblasts that were unmodified or modified to secrete brain-derived neurotrophic factor (BDNF).

Abnormal spontaneous potentials in distal muscles in animal models of spinal cord injury.

Spontaneous potentials in skeletal muscle distal to human spinal cord injury (SCI) have been reported in the literature. Two animal models of SCI were studied for the presence of similar potentials. Six rats and two cats with surgical transections of the thoracic spinal cord were followed for 4-6 weeks with serial electromyography.