Coastal Science for Resilience and Management at the Cape Hatteras National Seashore, NC, USA

National seashores are cherished public lands with rich environmental, cultural, and historic resources. The Cape Hatteras National Seashore is one such coastal asset that is both bountiful yet vulnerable, with historic lighthouses, critical habitats, and recreational amenities alike facing threats of sea-level rise and continual storm and climate change impacts. Over 3 million visitors to the Seashore in 2021 set an annual visitation record. Historic resources such as the Bodie Island Lighthouse and Ocracoke Lighthouse are among the most visited sites, yet these assets are also among those most vulnerable to flooding, compromised structural integrity, and reduced accessibility. Future challenges to the protection and management of such resources are already being felt in the form of storms, extreme rainfall, and recurrent compound flooding. Such threats are also coincident with increasing visitation and recreational demand. This paper examines the science-based data that are being collected and management efforts underway to inform future planning, intervention, or adaptation to sea-level rise and barrier island evolution. The paper identifies the opportunities for mitigation and adaptation as well as potential environmental tipping points and limits to resilience by assessing the frequency and magnitude of flooding events and shoreline change

Symmetries and Systematics of Doubly Heavy Hadrons

We discuss the extension of the superflavor symmetry of doubly heavy baryons to states which contain an excited heavy diquark, and we examine some of the consequences of this symmetry for the spectra of doubly heavy baryons and heavy mesons. We explore the ramifications of a proposed symmetry that relates heavy diquarks to doubly heavy mesons. We present a method for determining how the excitation energy of a system containing two heavy quarks will scale as one changes the strength of the interactions and the reduced mass of the system. We use this to derive consequences of the heavy diquark-doubly heavy meson symmetry. We compare these consequences to the results of a quark model as well as the experimental data for doubly and singly heavy mesons. We also discuss the possibility of treating the strange quark as a heavy quark and apply the ideas developed here to strange hadrons.Comment: 23 pages, 2 figures, and 17 tables include

Evaluation of “Dream Herb,” Calea zacatechichi

A recent surge in the use of dietary supplements, including herbal remedies, necessitates investigations into their safety profiles. “Dream herb,” Calea zacatechichi, has long been used in traditional folk medicine for a variety of purposes and is currently being marketed in the US for medicinal purposes, including diabetes treatment. Despite the inherent vulnerability of the renal system to xenobiotic toxicity, there is a lack of safety studies on the nephrotoxic potential of this herb. Additionally, the high frequency of diabetes-associated kidney disease makes safety screening of C. zacatechichi for safety especially important. We exposed human proximal tubule HK-2 cells to increasing doses of this herb alongside known toxicant and protectant control compounds to examine potential toxicity effects of C. zacatechichi relative to control compounds. We evaluated both cellular and mitochondrial functional changes related to toxicity of this dietary supplement and found that even at low doses evidence of cellular toxicity was significant. Moreover, these findings correlated with significantly elevated levels of nephrotoxicity biomarkers, lending further support for the need to further scrutinize the safety of this herbal dietary supplement

Ds0*(2317) and Ds1(2460) mesons in two-body B-meson decays

We analyze the branching ratios of B to D(*) + Ds0*(Ds1) decays using the factorization hypothesis. The B to D(*) transition form factors are taken from a model-independent analysis done by Caprini, Lellouch and Neubert based on heavy quark spin symmetry and dispersive constraints, including short-distance and power corrections. The leptonic decay constants fDs0* and fDs1 are calculated assuming a molecular structure for the Ds0* and Ds1 mesons. The calculated branching ratios of B-meson two-body decays are compared with experimental data and other theoretical results.Comment: 12 pages, 2 figure

Hypothyroidism and the risk of lower extremity arterial disease

Background: Although an independent association between hypothyroidism and coronary artery disease has been demonstrated, few studies have examined the association between hypo-thyroidism and peripheral arterial disease. In the current study, we test the hypothesis that there is an independent association between hypothyroidism and lower extremity arterial disease. Methods: We retrospectively compared the prevalence of hypothyroidism in patients who had infra-inguinal arterial bypass surgery over a 6-year period with that of a control group of surgical patients who had pure cardiac valve surgery during the same time period. Both unadjusted and adjusted odds ratios were calculated to estimate the association between hypothyroidism and lower extremity arterial disease. Results: A total of 614 cases and 529 control subjects had surgery during the study period. When comparing all subjects, there was no association between hypothyroidism and lower extremity arterial disease (unadjusted odds ratio 0.88; 95% confidence intervals [CI]: 0.61-1.28). However, gender was found to be a significant effect modifier (P \u3c 0.001), and gender-stratified analyses were subsequently performed. In men, there was a positive independent association between hypothyroidism and lower extremity arterial disease (adjusted odds ratio 2.65; 95% CI: 1.19-5.89), whereas in women there was a negative independent association (adjusted odds ratio 0.22; 95% CI: 0.11-0.46). Conclusions: Gender is a significant effect modifier for the association between hypothyroidism and lower extremity arterial disease. The association is positive in men and negative in women. Future prospective studies that evaluate hypothyroidism as a risk factor for peripheral arterial disease should consider gender stratification in order to corroborate this finding. © 2010 Mazzeffi et al, publisher and licensee Dove Medical Press Ltd

Weaning of immunosuppression in liver transplant recipients

Immunosuppression has been sporadically discontinued by noncompliant liver allograft recipients for whom an additional 4 1/2 years of follow-up is provided. These anecdotal observations prompted a previously reported prospective drug withdrawal program in 59 liver recipients. This prospective series has been increased to 95 patients whose weaning was begun between June 1992 and March 1996, 8.4±4.4 (SD) years after liver replacement. A further 4 1/2 years follow-up was obtained of the 5 self-weaned patients. The prospectively weaned recipients (93 livers; 2 liver/kidney) had undergone transplantation under immunosuppression based on azathioprine (AZA, through 1979), cyclosporine (CsA, 1980-1989), or tacrolimus (TAC, 1989-1994). In patients on CsA or TAC based cocktails, the adjunct drugs were weaned first in the early part of the trial. Since 1994, the T cell-directed drugs were weaned first. Three of the 5 original self-weaned recipients remain well after drug-free intervals of 14 to 17 years. A fourth patient died in a vehicular accident after 11 years off immunosuppression, and the fifth patient underwent retransplantation because of hepatitis C infection after 9 drug-free years; their allografts had no histopathologic evidence of rejection. Eighteen (19%) of the 95 patients in the prospective series have been drug free for from 10 months to 4.8 years. In the total group, 18 (19%) have had biopsy proved acute rejection; 7 (7%) had a presumed acute rejection without biopsy; 37 (39%) are still weaning; and 12 (13%, all well) were withdrawn from the protocol at reduced immunosuppression because of noncompliance (n=8), recurrent PBC (n=2), pregnancy (n=1), and renal failure necessitating kidney transplantation (n=1). No patients were formally diagnosed with chronic rejection, but 3 (3%) were placed back on preexisting immunosuppression or switched from cyclosporine (CsA) to tacrolimus (TAC) because of histopathologic evidence of duct injury. Two patients with normal liver function died during the trial, both from complications of prior chronic immunosuppression. No grafts suffered permanent functional impairment and only one patient developed temporary jaundice. Long surviving liver transplant recipients are systematically overimmunosuppressed. Consequently, drug weaning, whether incomplete or complete, is an important management strategy providing it is done slowly under careful physician surveillance. Complete weaning from CsA-based regimens has been difficult. Disease recurrence during drug withdrawal was documented in 2 of 13 patients with PBC and could be a risk with other autoimmune disorders

The Inner Halo of M87: A First Direct View of the Red-Giant Population

An unusually deep (V,I) imaging dataset for the Virgo supergiant M87 with the Hubble Space Telescope ACS successfully resolves its brightest red-giant stars, reaching M_I(lim) = -2.5. After assessing the photometric completeness and biasses, we use this material to estimate the metallicity distribution for the inner halo of M87, finding that the distribution is very broad and likely to peak near [m/H] ~ -0.4 and perhaps higher. The shape of the MDF strongly resembles that of the inner halo for the nearby giant E galaxy NGC 5128. As a byproduct of our study, we also obtain a preliminary measurement of the distance to M87 with the TRGB (red-giant branch tip) method; the result is (m-M)_0 = 31.12 +- 0.14 (d = 16.7 +- 0.9 Mpc). Averaging this result with three other recent techniques give a weighted mean d(M87) = (16.4 +- 0.5) Mpc.Comment: In press for Astronomy and Astrophysic

Perspectives on fatigue in short-haul flight operations from US pilots: A focus group study

There are few studies investigating the impact of fatigue in short-haul flight operations conducted under United States (US) 14 Code of Federal Regulations Part 117 flight and duty limitations and rest requirements. In order to understand the fatigue factors unique to short-haul operations, we conducted a series of focus groups across four major commercial passenger airlines in the US. Ninety short-haul pilots were recruited through emails distributed by airline safety teams and labor representatives. Fourteen focus groups were conducted via an online conferencing platform in which participants were asked to identify short-haul schedules and operations that they felt: a) elevated fatigue, b) were not fatiguing, and c) were important to study. Data were collected anonymously and coded using conventional qualitative content analysis, with axial coding and summative analysis used to identify main themes and over-arching categories. The six fatigue factor categories identified were: circadian disruption, high workload, inadequate rest opportunity, schedule changes, regulation implementation and policy issues, and long sits. It appears that additional mitigation strategies may be needed to manage fatigue in short-haul operations beyond the current regulations. Future field studies of short-haul operations in the US should investigate the prevalence and impact of these factors