Ergonomic Case Study of an Industrial Pipefitter

Industrial Nuclear Power Plant professionals risk life and limb every day to keep the lights on at night. The complex tasks these workers must complete day after day put increased strain on their bodies and overtime can result in Work-Related Musculoskeletal Disorders (WMSD). For this case study, a combination of interviews and surveys were used to gather information on our subject’s general body part discomfort. Common tasks performed by an Industrial Power Plant Pipefitter were then assessed using the Moore-Garg Strain Index and the Threshold Limit Value for Hand Activity (TLV) to determine potential risk of WMSDs. The results of both assessments showed that the tasks as hazardous or potentially hazardous. Based on the results of the ergonomic assessments as well as the interview and survey a list of future recommendations was compiled to reduce the ergonomic risks associated with pipefitting. These recommendations include vibration suppression equipment, external body mounts to distribute weight, and more efficient power tools to reduce strain on the worker

Fire Rebuild

The “Fire Rebuild” project involves the structural design of a single-family residence and garage. The original property was destroyed in the Tubb’s Fire, which swept through the city of Santa Rosa in 2017. The original structures were damaged beyond repair and allowed for the owner to customize the property. Following conventional residential building in the United States, the structures were designed as light framed construction, using a mixture of douglas-fir and engineered lumber. As the property is located in a WUI (Wildlife Urban Interface), and a historic California burn scar, special consideration was given to the materials and design of the residence and garage. The design was originally completed in 2019 and has been updated to meet the 2019 California Building Code (CBC)

Localization of a collagenous protein in the organic matrix of spicules from the octocoral Leptogorgia virgulata (Cnidaria: Gorgonacea)

Calcareous body inclusions are commonly found throughout the invertebrate taxa. Elaborately structured calcium carbonate spicules are the major mineralized body inclusions of the gorgonian, Leptogorgia virgulata. Spicule formation in this octocoral, as well as other calcium carbonate invertebrate structures, is apparently regulated by the intra-spicule organic matrix. Recent findings show that the insoluble fraction of the spicule organic matrix is collagenous. Collagen, although integral to calcium phosphate structures found in vertebrates is not usually associated with the formation of invertebrate calcium carbonate structures. Interestingly, collagen is present in the organic matrix during the summer but absent in winter. This suggests that there is a seasonal turnover of collagen. Antibodies (supplied by Dr. N. Watabe, University of South Carolina) were directed against the purified collagenous fractions from summer samples. Immunocytochemical techniques were subsequently employed at the electron microscope level and localization of this collagen fraction was determined in animals collected throughout the year. The location of the collagenous fraction of the organic matrix was determined from the time of the initial disappearance from spicules in winter to its reappearance during the following spring and summer. Several mechanisms addressing the fate of the collagen during the winter months are discussed. In addition this study also produced the first evidence for extracellular spicule growth in L. virgulata

Discovery of long-period variable stars in the very-metal-poor globular cluster M15

We present a search for long-period variable (LPV) stars among giant branch stars in M15 which, at [Fe/H] ~ -2.3, is one of the most metal-poor Galactic globular clusters. We use multi-colour optical photometry from the 0.6-m Keele Thornton and 2-m Liverpool Telescopes. Variability of delta-V ~ 0.15 mag is detected in K757 and K825 over unusually-long timescales of nearly a year, making them the most metal-poor LPVs found in a Galactic globular cluster. K825 is placed on the long secondary period sequence, identified for metal-rich LPVs, though no primary period is detectable. We discuss this variability in the context of dust production and stellar evolution at low metallicity, using additional spectra from the 6.5-m Magellan (Las Campanas) telescope. A lack of dust production, despite the presence of gaseous mass loss raises questions about the production of dust and the intra-cluster medium of this cluster.Comment: 13 pages, 9 figures, accepted by MNRA

Acute neuroinflammation induces AIS structural plasticity in a NOX2-dependent manner

Background Chronic microglia-mediated inflammation and oxidative stress are well-characterized underlying factors in neurodegenerative disease, whereby reactive inflammatory microglia enhance ROS production and impact neuronal integrity. Recently, it has been shown that during chronic inflammation, neuronal integrity is compromised through targeted disruption of the axon initial segment (AIS), the axonal domain critical for action potential initiation. AIS disruption was associated with contact by reactive inflammatory microglia which wrap around the AIS, increasing association with disease progression. While it is clear that chronic microglial inflammation and enhanced ROS production impact neuronal integrity, little is known about how acute microglial inflammation influences AIS stability. Here, we demonstrate that acute neuroinflammation induces AIS structural plasticity in a ROS-mediated and calpain-dependent manner. Methods C57BL/6J and NOX2−/− mice were given a single injection of lipopolysaccharide (LPS; 5 mg/kg) or vehicle (0.9% saline, 10 mL/kg) and analyzed at 6 h–2 weeks post-injection. Anti-inflammatory Didox (250 mg/kg) or vehicle (0.9% saline, 10 mL/kg) was administered beginning 24 h post-LPS injection and continued for 5 days; animals were analyzed 1 week post-injection. Microglial inflammation was assessed using immunohistochemistry (IHC) and RT-qPCR, and AIS integrity was quantitatively analyzed using ankyrinG immunolabeling. Data were statistically compared by one-way or two-way ANOVA where mean differences were significant as assessed using Tukey’s post hoc analysis. Results LPS-induced neuroinflammation, characterized by enhanced microglial inflammation and increased expression of ROS-producing enzymes, altered AIS protein clustering. Importantly, inflammation-induced AIS changes were reversed following resolution of microglial inflammation. Modulation of the inflammatory response using anti-inflammatory Didox, even after significant AIS disruption occurred, increased the rate of AIS recovery. qPCR and IHC analysis revealed that expression of microglial NOX2, a ROS-producing enzyme, was significantly increased correlating with AIS disruption. Furthermore, ablation of NOX2 prevented inflammation-induced AIS plasticity, suggesting that ROS drive AIS structural plasticity. Conclusions In the presence of acute microglial inflammation, the AIS undergoes an adaptive change that is capable of spontaneous recovery. Moreover, recovery can be therapeutically accelerated. Together, these findings underscore the dynamic capabilities of this domain in the presence of a pathological insult and provide evidence that the AIS is a viable therapeutic target

Myelin-associated glycoprotein and myelin galactolipids stabilize developing axo-glial interactions

We have analyzed mice that lack both the myelin-associated glycoprotein (MAG) and the myelin galactolipids, two glial components implicated in mediating axo-glial interactions during the myelination process. The single-mutant mice produce abnormal myelin containing similar ultrastructural abnormalities, suggesting that these molecules may play an overlapping role in myelin formation. Furthermore, the absence of the galactolipids results in a disruption in paranodal axo-glial interactions, and we show here that similar, albeit less severe, abnormalities exist in the developing MAG mutant. In the double-mutant mice, maintenance of axo-glial adhesion is significantly more affected than in the single mutants, supporting the overlapping function hypothesis. We also show that independently of MAG, galactolipids, and paranodal junctional components, immature nodes of Ranvier form normally, but rapidly destabilize in their absence. These data indicate that distinct molecular mechanisms are responsible for the formation and maintenance of axo-glial interactions