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Damped Oscillating Phosphoryl Transfer Reaction in the Cyanobacterial Circadian Clock
Get PDFMost organisms have circadian clocks to ensure the metabolic cycle to resonate with the rhythmic environmental changes without “damping,” or losing robustness. Cyanobacteria is the oldest and simplest form of life that is known to harbor this biological intricacy. Its KaiABC-based central oscillator proteins can be reconstituted inside a test tube, and the post-translational modification cycle occurs with 24 h periodicity. KaiC’s two major phosphorylation sites, Ser-431 and Thr-432, become phosphorylated and dephosphorylated by interacting with KaiA and KaiB, respectively. Here, we mutate Thr-432 into Ser to find the oscillatory phosphoryl transfer reaction damps. Previously, this mutant KaiC was reported to be arrhythmic in vivo. However, we found that the mutant KaiC gradually loses the ability to run in an autonomous manner and stays constitutively phosphorylated after 3 cycles in vitro
Characterizing the vegetation and effects of climate change on Parris Island, a sea island ecosystem
Get PDFCoastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps Recruit Depot Parris Island (MCRDPI), a barrier island in South Carolina, USA, and to investigate potential evidence of SLR in these types. Our chapter 2 objectives then focused on describing habitat conversion driven by SLR and storm surge over the last 14 years on MCRDPI. First, we established 57 permanent vegetation plots for long-term monitoring of the coastal vegetation types present on the island and characterized the main environmental variables associated with the distributions of these types. Using data from the vegetation surveys, we identified the USNVC Associations that were present on the island and employed supervised deep learning classification to map their distributions. Additionally, we characterized habitat conversion from 2008 to 2022, relating those changes to relative SLR and storm surge activity that occurred during this time. We identified four salt marsh Associations and eight forest or woodland Associations. The distributions of these vegetation types were primarily driven by salinity and elevation gradients. The marsh types dominated the landscape, covering ~57% of the classified area, while forest types covered ~13%. Over the last 14 years, 6.9% (227 ha) of the classified extent of MCRDPI experienced habitat conversion. Most of this conversion occurred between 2015 and 2018, when two intense storm surge events impacted the island. Conversion of wetland to open water was the largest change class, representing approximately 22% of the total habitat conversion that took place over the 14-year period, resulting in a net loss of salt marsh on MCRDPI. While the timeframe in which most of the habitat conversion took place indicates storm surges as the direct source of conversion, the extreme rate of relative SLR that occurred within this period may have degraded upland vegetation prior to these intense disturbances, leaving them vulnerable to and thus exacerbating the storm damage. The vegetation survey framework established here will enhance continued monitoring efforts, which will provide further insight into the effects of climate change on coastal habitat conversion processes and allow the natural resources department on MCRDPI to make informed management decisions. Our change detection efforts indicate that marsh loss is occurring, even over relatively short time frames. Reducing upland infrastructure directly bordering the marsh edge may facilitate marsh migration and prolong the stability of these habitats and thus the ecosystem services that they afford
Undated Photo of Chuck Yeager at a Formal event
Get PDFPhotograph of Chuck Yeager at a formal event. Other participants are unnamed, and the photo has no date.https://mds.marshall.edu/yeager/1231/thumbnail.jp
Chuck Yeager Press Release Sabre Jet Fighter
No full textChuck Yeager standing next to Ralph Rund in front of an F-86E Sabre Jet Fighter. Date is unlisted but is likely during the Korean War, based on the text description.https://mds.marshall.edu/yeager/1241/thumbnail.jp
Eccentric pairs: Analytic gravitational waves from binary black holes in elliptic orbits
Get PDFGravitational waves (GW) from eccentric binaries have intricate signals encoding important features about the location, creation and evolution of the sources. Eccentricity shortens the merger time, making the emitted GW statistically predominant in the observed data once detectors will reach the required sensitivity. We present a novel implementation of fully analytical GW templates from eccentric binary black hole (BBH) mergers within the Wolfram Mathematica software. We increase the accuracy by identifying and minimizing the possible source of errors. We start with an overview of the physics involved in eccentric mergers, then assemble the strain for the inspiral by employing up to six post-Newtonian (PN) corrections. We complete the eccentric inspiral with the quasi-circular Backwards one Body (BOB) merger model in frequency, amplitude and phase, then we build the hybrid GW strain for the whole evolution of the binary. For low eccentricity, we reach coincidence in the overlap, with no ambiguity in the time interval, a remarkable improvement from the usual matching techniques. For high-eccentricity, we compensate for the implicit quasi-circular assumption of the BOB approach, by introducing a small rescaling in amplitude. Our streamlined implementation is relevant for the new field of GW astronomy and is straightforward to understand, use and extend, offering researchers in the field a valuable open resource tool
A commonly misdiagnosed rare pulmonary disease: Idiopathic pleuroparenchymal fibroelastosis
Get PDFAwareness among clinicians about Idiopathic pleuroparenchymal fibroelastosis (PPFE) is lacking and by the time patients are diagnosed with it, they were seen by multiple physicians and misdiagnosed multiple times. It is a rare condition that is characterized by fibrosis of the pleura and subpleural lung parenchyma, predominantly affecting the upper lobes. Most common cause of fibrosis in other processes is collagen predominant but in PPFE fibrosis is usually caused by elastic fibers. Verhoeff-Van Gieson stain from lung biopsies in patients who presented with fibrosis in the upper pleural and parenchymal areas will help in establishing the diagnosis by demonstrating the elastic fibers. We also need to rule out the possibility of other lung parenchymal conditions like usual interstitial pneumonia, nonspecific interstitial pneumonitis, pulmonary apical cap etc. We have presented a case report on PPFE to bring attention to clinicians so that patients are diagnosed early
Utilization of the Social Determinants of Mental Health Framework with Older Adults for Assessment, Case Conceptualization, and Treatment Planning
Get PDFThis conceptual paper will aid counselors and mental health professionals in obtaining insight to utilizing a Social Determinants of Mental Health Framework with older adult clients. Further, the article incorporates the Multicultural and Social Justice Counseling Competencies to further contextualize the therapeutic alliance. The authors utilize the Social Determinants of Mental Health Framework to frame counseling assessment, case conceptualization, and treatment planning to improve the mental health outcomes of older adults. The article utilizes a specific case example to assess, conceptualize, and plan treatment for an older adult client contextualized in their environment