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Non-Contact Wind Turbine Blade Crack Detection Using Laser Doppler Vibrometers
Get PDFIn response to the growing global demand for both energy and a clean environment, there has been an unprecedented rise in the utilization of renewable energy. Wind energy plays a crucial role in striving for carbon neutrality due to its eco-friendly characteristics. Despite its significance, wind energy infrastructure is susceptible to damage from various factors including wind or sea waves, rapidly changing environmental conditions, delamination, crack formation, and structural deterioration over time. This research focuses on investigating non-destructive testing (NDT) of wind turbine blades (WTBs) using approaches based on the vibration of the structures. To this end, WTBs are first made from glass fiber-reinforcement polymer (GFRP) using composite molding techniques, and then a short pulse is generated in the structure by a piezoelectric actuator made from lead zirconate titanate (PZT-5H) to generate guided waves. A numerical approach is presented based on solving the elastic time-harmonic wave equations, and a laser Doppler vibrometer (LDV) is utilized to collect the vibrational data in a remote manner, thereby facilitating the crack detection of WTBs. Subsequently, the wave propagation characteristics of intact and damaged structures are analyzed using the Hilbert–Huang transformation (HHT) and fast Fourier transformation (FFT). The results reveal noteworthy distinctions in damaged structures, where the frequency domain exhibits additional components beyond those identified by FFT, and the time domain displays irregularities in proximity to the crack region, as detected by HHT. The results suggest a feasible approach to detecting potential cracks of WTBs in a non-contact and reliable way
EXPLORING CULTURALLY RESPONSIVE INSTRUCTION IN ADVANCED PLACEMENT SCIENCE: PERSPECTIVES FROM TEACHERS OF UNDERREPRESENTED STUDENTS
No full textThe study investigated teacher perceptions on the influence of culturally responsive instruction in advanced placement (AP) science courses, focusing on teachers of underrepresented student populations. The study explored how teachers viewed these educational strategies to support diverse student groups and bridge opportunity gaps prevalent in AP science education. Through narrative analysis, the research considered teachers\u27 perceptions and implementations of culturally responsive practices and the engagement of underrepresented students in AP science. This exploration interpreted the potential of culturally responsive pedagogy to enhance student outcomes, participation, and interest in science, contributing to a more equitable and inclusive AP science experience while empowering a broader and more diverse generation of future scientists. The findings from this study revealed details about implementing Culturally Responsive Teaching (CRT) practices. Teacher reported that integrating culturally responsive instructional approaches was crucial for supporting students who may be considered non-traditional AP science students. The findings indicated that teachers believe integrating culturally responsive science instruction could inform their narratives as instructors to leverage student curiosity to explore complex scientific challenges
Repetitive Mild Traumatic Brain Injury Impairs Norepinephrine System Function and Psychostimulant Responsivity
No full textTraumatic brain injury (TBI) is a complex pathophysiological process that results in a variety of neurotransmitter, behavioral, and cognitive deficits. The locus coeruleus-norepinephrine (LC-NE) system is a critical regulator of arousal levels and higher executive processes affected by TBI including attention, working memory, and decision making. LC-NE axon injury and impaired signaling within the prefrontal cortex (PFC) is a potential contributor to the neuropsychiatric symptoms after single, moderate to severe TBI. The majority of TBIs are mild, yet long-term cognitive deficits and increased susceptibility for further injury can accumulate after each repetitive mild TBI. As a potential treatment for restoring cognitive function and daytime sleepiness after injury psychostimulants, including methylphenidate (MPH) that increase levels of NE within the PFC, are being prescribed off-label . The impact of mild and repetitive mild TBI on the LC-NE system remains limited. Therefore, we determined the extent of LC-NE and arousal dysfunction and response to therapeutic doses of MPH in rats following experimentally induced single and repetitive mild TBI. Microdialysis measures of basal NE efflux from the medial PFC and arousal measures were significantly lower after repetitive mild TBI. Females showed higher baseline PFC-NE efflux than males following single and repetitive mild TBI. In response to MPH challenge, males exhibited a blunted PFC-NE response and persistent arousal levels following repetitive mild TBI. These results provide critical insight into the role of catecholamine system dysfunction associated with cognitive deficits following repeated injury, outcome differences between sex/gender, and lack of success of MPH as an adjunctive therapy to improve cognitive function following injury
IMPLEMENTING 1.5 MILLIMETER INTERNAL DIAMETER COLUMNS AND A PORTABLE CAPILLARY COLUMN INSTRUMENT INTO MONOCLONAL ANTIBODY ANALYTICAL WORKFLOWS
Get PDFUsing 1.5 mm inner diameter (i.d.) columns to bridge the gap between routinely used 2.1 mm i.d. columns and capillary bore columns allows for a sequential but significant increase in performance without the need for specialized equipment associated with very low dispersion liquid chromatography (LC) systems. These 1.5 mm i.d. columns balance an increase in sensitivity compared to 2.1 mm i.d. columns (theoretically doubling the time-domain peak area in mass sensitive detectors for the same mass load), while mitigating the efficiency losses due to extra-column dispersion effects that are commonly observed with 1.0 mm i.d. columns. Here, the use of 1.5 mm i.d. columns was applied to LC/UV analysis of small molecules and LC/MS analysis of recombinant monoclonal antibodies. The 1.5 mm i.d. column exhibited a two-to-threefold improvement in analyte peak area signal for small molecules as well as for intact, subunit, and peptide levels of antibody analysis. Still, the utility of capillary columns for the analysis of recombinant monoclonal antibodies and other high molecular weight molecules has its benefits. Improvements in column performance and ruggedness along with instrumentation improvement would increase the use of capillary systems. One modern trend in capillary instrumentation is miniaturization of the equipment to such a small size that it is portable and can be used inside or outside of a laboratory. Examples of separations using such an instrument are shown
Chemotherapy Drug Release from Hollow Core Polyethyleneimine Nanoparticles
No full textNovel anticancer delivery vehicles are arising from engineered nanostructured materials. This work involved the synthesis, characterization, and release of novel hollow core polymeric nanoparticles (HCPNPs) for controlled drug delivery. Polyethyleneimine (PEI) was bound to AuNPs, forming polymer-shell nanoparticles with dissolution of the gold core via iodine forming HCPNPs with drug intercalated DNA bound to the surface. A high density (85 molecules/particle) of DNA intercalated with daunorubicin was conjugated. Particles were spherical with an average diameter of 105.7 ± 17.3 nm and zeta potential of 20.4 ± 3.54 mV. We hypothesize the DNA backbone electrostatically condensed to the primary amines on the surface of the particle toroidally, weaving itself within the polymer shell. Ionic concentration and charge ratio modifications were investigated for DNA binding to determine the optimal method of particle synthesis. An average of 874 ± 40.1 daunorubicin molecules were loaded per HCPNP. Release of drug from hollow core formulation was observed to be greater than of solid core counterparts by 225 ± 44.6 mg more of drug per cm3. HCPP-DNA-Daun also exhibited extended release of over 12 hours in comparison to a 1-hour release from solid core counterparts. Cell studies showed HCPP-DNA-Daun induced 46% cellular death in comparison to cellular death of 12% in free drug equivalent. Lipid raft-endocytosis and clathrin-mediated endocytosis was determined to be the primary internalization methods of particles through endocytotic inhibitor exposure. HCPP-DNA-Daun have presented themselves as a novel anticancer effort with greater potential efficacy than traditional treatment methods
POTENT AND SELECTIVE SMALL MOLECULE MCL-1 INHIBITOR DEMONSTRATES ANTI-MYELOMA ACTIVITY AND OVERCOMES CHEMOTHERAPY RESISTANCE
Get PDFDespite a record number of clinical studies investigating various anti-myeloma treatments, the 5-year survival rate for multiple myeloma (MM) patients in the US is only 55%, and nearly all patients relapse. Poor patient outcomes demonstrate that myeloma cells are born to survive” which means they can adapt and evolve following treatment. Thus, new therapeutic approaches to combat survival mechanisms and target treatment resistance are required. Importantly, Mcl-1, anti-apoptotic protein, is required for the development of MM and treatment resistance. This study looks at the possibility of KS18, a selective Mcl-1 inhibitor, to treat MM and overcome resistance. Our investigation demonstrates that KS18 effectively induces cell death in MM by dual regulatory mechanisms targeting Mcl-1 protein at both transcriptional and post-translational levels. KS18 triggered caspase-dependent apoptosis in MM patient samples and bortezomib-resistant cells, synergizing with venetoclax to boost apoptosis. Furthermore, the study shows the tremendous impact of KS18 in inhibiting colony formation in bortezomib-resistant cells and demonstrates tumor shrinkage in KS18-treated NSG mice without notable toxicity signs, indicating its powerful anti-neoplastic and anti-resistance characteristics. This study strongly implies that KS18 may treat MM and provide new hope to patients who are experiencing recurrence or resistance
Brain Connectivity Pattern Changes Associated With Psychedelic-Assisted Psychotherapy
Get PDFPsychedelic-assisted psychotherapy (PAP) has shown promising therapeutic benefits for various psychiatric disorders, but the underlying neural mechanisms remain unclear. This study aimed to investigate the effects of psychedelics on brain connectivity patterns using functional magnetic resonance imaging (fMRI). A comprehensive literature search was conducted in PubMed and Google Scholar databases using relevant keywords related to psychedelics, connectivity, therapy, and fMRI. Only studies involving major psychedelic compounds (LSD, psilocybin, ayahuasca) and measuring outcomes via fMRI were included.
The findings from the reviewed studies suggest that psychedelics induce acute disruptions in normal large-scale brain network patterns, leading to a compromised modular but enhanced global connectivity, referred to as network disintegration and desegregation. This internal brain state correlates with aspects of the psychedelic experience, such as ego dissolution. Post-acute effects, one day after psilocybin treatment, revealed changes in cerebral blood flow and resting-state functional connectivity compared to baseline, including increased default mode network (DMN) integrity and functional connectivity within the DMN.
The proposed therapeutic mechanisms of PAP involve the synergistic combination of the psychedelic substance and the accompanying psychotherapy. Further research is warranted to delineate the specific brain connectivity changes associated with different psychedelic compounds and their relationship to therapeutic outcomes in various psychiatric conditions
Can Nutritional Supplements Benefit Patients Receiving Treatment for Neurodegenerative Disorders?
Get PDFAs the prevalence of neurocognitive disorders rises globally, developing new methodologies of prevention and treatment is crucial. This literature review examines the efficacy of adding nutritional supplements, specifically nootropics, with traditional pharmacological regimens on various neurocognitive and neurodegenerative disorders. Primary, peer-reviewed research, including both human and animal studies, was assesed to determine if there was a benefifical, minimal, or detrimental effect on symptom progression. The inclusion criteria focused on studies that evaluated the reduction in disease markers or symptoms following supplement use. The findings reveal that natural supplements generally support disease management. Significant improvements were noted with specific combinations like valproate and resveratrol in amyotrophic lateral sclerosis models, and Interferon-β with sesame oil in multiple sclerosis, showing decreased disease markers and better patient outcomes. This research suggests that nootropics and nutritional supplements can be beneficial in managing neurocognitive disorders, potentially improving patient quality of life and disease progression. Further investigations should explore these effects in human trials and consider the benefits of multiple supplement regimens
Effect of Exercise Intervention on Facioscapulohumeral Muscular Dystrophy (FSHD)
Get PDFFacioscapulohumeral Muscular Dystrophy (FSHD) is a common muscular dystrophy. The facial muscles, shoulder girdles, and upper arms are notably affected.1 A common presenting symptom is asymmetrical scapular winging and further symptoms may include but are not limited to: loss of pectoral muscles, fatigue, severe pain, pathologic spinal curvatures, and foot drop.2 It is a particularly debilitating muscular dystrophy, with 20% of people \u3e50 y.o. requiring a wheelchair.3 With no approved therapeutics, patients are managed symptomatically.3 This review sought to determine the effect of different exercise interventions on patients with FSHD. It is hypothesized that exercise may prevent need for assistive devices and increase patient quality of life. A literature review was conducted with search across PubMed, Cochrane library, Web of Science and Embase, with 15 articles selected from the results. All three forms of training, aerobic, strength, and anaerobic, were found to have positive effects on patients with FSHD. Positive effects of aerobic and strength training interventions include reduced levels of fatigue, increased oxygen uptake, improved muscle strength, and functional improvements in fitness, walking speed, and other functional tasks.1-3,6-7 In addition, neither aerobic nor strength training resulted in any signs of further muscle damage.2-3,11 Notably less research has been conducted on the impacts of HIIT or other forms of anaerobic training on patients with FSHD. Further research should be performed to determine the specifically most optimal routine for these patients in addition to further evaluation of the effects of anaerobic exercise