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Vibrational overtone predissociation spectra of tetramethyldioxetane, obtained by monitoring the products of the vibrational overtone initiated unimolecular decomposition in both a room temperature sample and in a free jet, reveal the interactions that are likely to be responsible for the structure in the spectrum. The room temperature measurements provide spectra of the second, third, and fourth CH stretching overtone transitions (3νCH, 4νCH, and 5νCH ) and of combination bands in which a single quantum of methyl deformation is excited along with the stretching vibration. These spectra show the greatest complexity for the lowest energy transition (3νCH) and become simpler for higher levels of excitation. Two prominent maxima in the pure CH stretching overtone spectra come from hydrogen atoms in inequivalent environments in the molecule, but additional structure probably reflects a Fermi resonance between the stretching vibration and the methyl deformation. [ABSTRACT FROM AUTHOR]

Vibrational overtone excitation of tetramethyldioxetane in a free jet expansion creates a nearly monoenergetic ensemble of molecules for which the unimolecular reaction rate is directly measured by monitoring the temporal evolution of the electronically excited acetone formed in the reaction. The measurement for the 5νCH vibrational overtone transition determines the unimolecular reaction rate constant at one energy. It is possible to adjust the parameters in the RRKM calculation of the rate constant to obtain agreement with this nearly monoenergetic measurement and to average the calculated energy dependent rate constant over a thermal distribution of initial vibrational energies for comparison with data on room temperature samples. The calculation reproduces the growth of the chemiluminescence following excitation of two CH stretching transitions 4νCH and 5νCH and of a combination transition involving the methyl deformation 4νCH +νdef. [ABSTRACT FROM AUTHOR]

As conservation efforts regarding green sea turtles, Chelonia mydas, continue, it is imperative to document behaviors and foraging habits/habitats of understudied populations. We have conducted an 18-month study dedicated to photographing the local population feeding alongside floating docks within the Guana Tolomato Matanzas estuary to determine the capability of matching head scale patterns efficiently through a pattern matching program: HotSpotter. To date, 195 unique sea turtles have been identified between two different marinas located in St. Augustine, FL. Of these, 98 were spotted more than once, with 39 of them being "tracked" for longer than a year. Temperature trends were also monitored in conjunction, showing that more individuals appeared during the warmer months of the year. The evidence, overall, indicates that these locations host a resident population of green sea turtles, leading to the need for a discussion on potential threats originating from the usage of these marinas by humans.

Housing discrimination and racial segregation have a long history in the United States. The 1930's Home Owners' Loan Corporation (HOLC) "residential security maps," recently digitized, have become a popular visualization of Depression era mortgage lending risk patterns across American cities. Numerous housing policies have since been instituted, including the Home Mortgage Disclosure Act (HMDA), but mortgage lending bias persists. The degree to which detailed spatial patterns of bias have persisted or changed along with urban change is not well understood. We compare historic HOLC grades and contemporary levels of mortgage lending bias using spatially detailed HMDA data. We further examine the relationship between HOLC risk grades and contemporary racial and ethnic settlement patterns. Results suggest that historical mortgage lending risk categorizations and settlement patterns are associated with contemporary mortgage lending bias and racial and ethnic settlement patterns. Concerted and deliberate efforts will be needed to change these patterns., Competing Interests: Declaration of Interest Statement No potential conflict of interest was reported by the authors.

Purpose: Since 2012, about 80 specialty societies have released Choosing Wisely (CW) recommendations aimed at reducing the use of low-value, unproven, or ineffective medical services. The extent to which these recommendations have influenced the behavior of physicians and patients remains largely unknown., Methods: Using MarketScan Commercial Claims and Medicare Supplemental and Coordination of Benefits databases, we identified annual cohorts of women with incident, early-stage breast cancer and estimated the prevalence of four initial treatment and six surveillance metrics deemed as low-value breast cancer care by CW. Multivariable logistic regressions were subsequently used to estimate temporal trends and regional variation in the use of these metrics, with a special focus on the year of CW's publication., Results: There were 122,341 women identified as undergoing treatment for incident breast cancer between 2010 and 2014. Two of the four low-value initial treatment metrics and four of the six low-value surveillance metrics declined significantly over time. The temporal trend of declining use, however, preceded the release of CW's guidelines. Declines ranged from 11.0% for follow-up mammography to 40.6% for receipt of surgical biopsy without an attempted needle biopsy. There were marked regional differences in use of low-value breast cancer care for all metrics, much of which persisted after publication of CW., Conclusions: With two notable exceptions, use of low-value breast cancer care has declined steadily since 2010. The declines, however, were not accelerated by the publication of CW recommendations.

Background: Many people with type 1 diabetes (T1D) do not achieve levels of exercise recommended by the American Diabetes Association, often due to unique barriers, including fear of hypoglycemia. This study aimed to broaden the understanding of barriers and facilitators to exercise among adults with T1D by exploring social media-specifically T1D-themed blogs-in addition to more traditional interviews and journals., Methods: Data sources included exercise-focused T1D blog posts (n = 67) and associated comments (n = 717), as well as interviews of and journals kept by adults with T1D (n = 10). Data were analyzed using a qualitative inductive thematic approach. Shared and unique themes were identified among the three data sources. Content mapping illustrates these relationships and interplay., Results: Three metathemes were identified: (1) exercise with T1D requires significant planning, (2) hypoglycemia often interrupts or causes alteration to exercise, and (3) "ordinary" activities can cause greater insulin sensitivity and hypoglycemia, much like planned exercise, but are often unrecognized as exercise. Unique themes found only in the blogs, only in interviews, or only in journals are also reported., Conclusions: Social media such as blogs can be a valuable addition to qualitative research, especially when combined with other sources of data. This study suggests a need for providing adults with T1D with more instruction on preventing hypoglycemia during exercise, as well as links to organized or online activities that can provide support and education. Health care providers may wish to consider strategies to help adults with T1D recognize glycemic impact from daily activities not typically recognized as exercise.

Purpose: To examine the relationship between patient and tumor characteristics, patterns of breast cancer care, and 5-year survival among a population-based cohort of elderly women with incident breast cancer, with a special focus on identifying sources of socioeconomic (SES) disparities in outcomes., Methods: We identified women with newly diagnosed breast cancer in 2006-2009 from the Surveillance and Epidemiology End Result study linked with Medicare claims. A Classification and Regression Tree (CART) model was applied to 13 individual indicators of neoadjuvant and adjuvant breast cancer treatment, tumor characteristics, and patient sociodemographic variables to identify patterns with the greatest discriminant value in predicting 5-year survival. We subsequently examined the extent to which these patterns varied by the patient's SES., Results: Survival probabilities associated with the 18 unique CART-identified patterns ranged from 22 to 87%. The number of positive axillary nodes was the best single discriminator between high and lower survival outcomes. The most common discriminant factor among patterns with poor (< 25%) survival was the absence of radiation treatment, followed by the presence of comorbidities, tumor size > 2 cm, and no breast surgery. Relative to high SES women, poor women were nearly four times (12.3% vs. 3.2%, p < 0.001) as likely to be classified in the pattern associated with worse survival, and less likely (31.7% vs. 52.9%, p = 0.04) to receive the pattern associated with the greatest survival., Conclusions: Greater adoption of effective patterns of care could improve survival of elderly women with incident breast cancer overall, and reduce SES disparities therein.

Introduction: Sleep loss can result in cognitive, motor, and neurobehavioral impairments. In an aviation context, this can cause a serious threat to flight safety. Therefore, the study aimed to investigate the effects of 24-h sleep deprivation on mood, fatigue, and airline pilot competencies., Methods: Seven subjects attended two 24-h testing periods, one with an 8-h sleep opportunity, and the other with no sleep opportunity (i.e., sleep deprivation). Subjects were required to complete a battery of mood, fatigue, and analogue measures of pilot competency tasks every 8 h (0 h, 8 h, 16 h, 24 h) throughout each testing period., Results: While total mood disturbance was found to significantly increase (83.42, SD = 25.7), both objective (352.71, SD = 42.00) and subjective (34.85, SD = 8.82) fatigue were found to significantly decrease following 24-h sleep deprivation. Cognitive flexibility (757.45, SD = 58.48) and hand-eye coordination (dominant hand only) (60.28, SD = 3.86) were also negatively impacted following 24-h sleep deprivation. However, working memory and situation awareness were not significantly negatively impacted by the bout of sleep deprivation., Discussion: Some pilot-specific task-related factors such as subjective fatigue, cognitive flexibility, and working memory were found to be particularly susceptible to sleep loss, with significant declines in performance observed following 16-h continuous wakefulness, suggesting reductions in optimal functioning following this period of wakefulness. Further investigation using more regular testing time points, employing additional pilot competencies, and using more aviation-specific tasks is warranted.O'Hagan AD, Issartel J, McGinley E, Warrington G. A pilot study exploring the effects of sleep deprivation on analogue measures of pilot competencies. Aerosp Med Hum Perform. 2018; 89(7):609-615.

We have highlighted that exposure of base-metal dental casting alloys to the acidogenic bacterium Streptococcus mutans significantly increases cellular toxicity following exposure to immortalized human TR146 oral keratinocytes. With Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), S. mutans-treated nickel-based (Ni-based) and cobalt-chromium-based (Co-Cr-based) dental casting alloys were shown to leach elevated levels of metal ions compared with untreated dental casting alloys. We targeted several biological parameters: cell morphology, viable cell counts, cell metabolic activity, cell toxicity, and inflammatory cytokine expression. S. mutans-treated dental casting alloys disrupted cell morphology, elicited significantly decreased viable cell counts (p < 0.0001) and cell metabolic activity (p < 0.0001), and significantly increased cell toxicity (p < 0.0001) and inflammatory cytokine expression (p < 0.0001). S. mutans-treated Ni-based dental casting alloys induced elevated levels of cellular toxicity compared with S. mutans-treated Co-Cr-based dental casting alloys. While our findings indicated that the exacerbated release of metal ions from S. mutans-treated base-metal dental casting alloys was the likely result of the pH reduction during S. mutans growth, the exact nature of mechanisms leading to accelerated dissolution of alloy-discs is not yet fully understood. Given the predominance of S. mutans oral carriage and the exacerbated cytotoxicity observed in TR146 cells following exposure to S. mutans-treated base-metal dental casting alloys, the implications for the long-term stability of base-metal dental restorations in the oral cavity are a cause for concern.

Background: Research shows that community-based membership organizations are effective partners in health promotion activities; however, most community organizations do not participate in such partnerships. There is little research regarding the geographical and organizational characteristics associated with participation., Objective: We examined the factors associated with community-based veterans service organization (VSO) units' decision to participate in a health promotion project., Methods: We collected location and organizational characteristics regarding 218 VSO units asked to participate in POWER, a partnership to improve hypertension self-management skills between the Medical College of Wisconsin, the Milwaukee Veterans Affairs Medical Center (VAMC) and Wisconsin branches of the American Legion, Veterans of Foreign Wars (VFW), Vietnam Veterans of America, and National Association of Black Veterans. We tested the association of these characteristics with participation using chi-square and Fisher's exact tests for categorical variables, and analysis of variance and the Kruskal-Wallis test for continuous variables. We used multivariable logistic regression to identify factors independently associated with participation., Results: In bivariable analyses, likelihood of participation was positively associated with increasing membership (p < .001), meeting attendance (p < .001), publication of an organizational newsletter (p < .001), presence of a women's auxiliary (p = .02), and location within 44 miles of the VAMC (p = .047). On multivariable analysis, only meeting attendance and census tract-level educational attainment predicted participation., Conclusions: Greater membership sizes, meeting attendance, and more group resources might be important factors for researchers to consider when initiating community-based health and wellness programs.

Nickel-chromium (Ni-Cr) alloys used in fixed prosthodontics have been associated with type IV Ni-induced hypersensitivity. We hypothesised that the full-thickness human-derived oral mucosa model employed for biocompatibility testing of base-metal dental alloys would provide insights into the mechanisms of Ni-induced toxicity. Primary oral keratinocytes and gingival fibroblasts were seeded onto Alloderm™ and maintained until full thickness was achieved prior to Ni-Cr and cobalt-chromium (Co-Cr) alloy disc exposure (2-72 h). Biocompatibility assessment involved histological analyses with cell viability measurements, oxidative stress responses, inflammatory cytokine expression and cellular toxicity analyses. Inductively coupled plasma mass spectrometry analysis determined elemental ion release levels. We detected adverse morphology with significant reductions in cell viability, significant increases in oxidative stress, inflammatory cytokine expression and cellular toxicity for the Ni-Cr alloy-treated oral mucosal models compared with untreated oral mucosal models, and adverse effects were increased for the Ni-Cr alloy that leached the most Ni. Co-Cr demonstrated significantly enhanced biocompatibility compared with Ni-Cr alloy-treated oral mucosal models. The human-derived full-thickness oral mucosal model discriminated between dental alloys and provided insights into the mechanisms of Ni-induced toxicity, highlighting potential clinical relevance., (Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Severe sepsis is common and often fatal. The expanding armamentarium of evidence-based therapies has improved the outcomes of persons with this disease. However, the existing national estimates of the frequency and outcomes of severe sepsis were made before many of the recent therapeutic advances. Therefore, it is important to study the outcomes of this disease in an aging US population with rising comorbidities., Methods: We used the Healthcare Costs and Utilization Project's Nationwide Inpatient Sample (NIS) to estimate the frequency and outcomes of severe sepsis hospitalizations between 2000 and 2007. We identified hospitalizations for severe sepsis using International Classification of Diseases, Ninth Revision, Clinical Modification codes indicating the presence of sepsis and organ system failure. Using weights from NIS, we estimated the number of hospitalizations for severe sepsis in each year. We combined these with census data to determine the number of severe sepsis hospitalizations per 100,000 persons. We used discharge status to identify in-hospital mortality and compared mortality rates in 2000 with those in 2007 after adjusting for demographics, number of organ systems failing, and presence of comorbid conditions., Results: The number of severe sepsis hospitalizations per 100,000 persons increased from 143 in 2000 to 343 in 2007. The mean number of organ system failures during admission increased from 1.6 to 1.9 (P < .001). The mean length of hospital stay decreased from 17.3 to 14.9 days. The mortality rate decreased from 39% to 27%. However, more admissions ended with discharge to a long-term care facility in 2007 than in 2000 (35% vs 27%, P < .001)., Conclusions: An increasing number of admissions for severe sepsis combined with declining mortality rates contribute to more individuals surviving to hospital discharge. Importantly, this leads to more survivors being discharged to skilled nursing facilities and home with in-home care. Increased attention to this phenomenon is warranted.

Blood clearance, urinary excretion, and spinal uptake of 99mTc-HEDP have been measured in ten normal control subjects. Blood clearance from 15 min is biexponential. Approximately 70% of the administered activity was excreted in the urine within 6 hr of injection. Spine-to-background ratios rise sequentially with time. Net normal bone uptake rises little after 2 hr and improved visualization of the normal skeleton therafter is due to reduction of blood background activity. In 13 patients with bone tumors, direct measurement of diphosphonate uptake by the tumor-involved and corresponding normal bone showed a continued rise in diphosphonate levels in the tumor-involved bone due to increased metabolic activity.

We studied splenic macrophage reticuloendothelial function in 18 patients with idiopathic membranous nephropathy and eight patients with mesangio-capillary glomerulonephritis by measuring the clearance from the circulation of technetium labelled, autologous, antibody coated erythrocytes (IgG cells) or heat damaged erythrocytes (HDE). Nine of 15 rhesus-D positive patients with membranous nephropathy had delayed clearance of the IgG cells and the defect did not correlate with disease activity. Circulating immune complexes were not detected in any of the patients with membranous nephropathy. The defect in clearance of the IgG cells in the membranous patients was associated with the presence of HLA-B8 and DR3. In the mesangio-capillary glomerulonephritis patients, the clearance rates of the IgG cells were fast-normal in six and enhanced in two, and correlated with the clearance of HDE. The clearance rates of the cells in this group correlated with the degree of hypocomplementaemia but not with the disease activity nor HLA haplotype.

In a series of 271 transplantations of renal allografts, performed over 10 years, the rates of graft survival, patient survival, and morbidity in the recipients of allografts from living related donors (47 allografts) have been compared with those in the recipients of cadaveric allografts (224 allografts). The one-year graft survival rates were 88% for allografts from living related donors (100%, if these were HLA-identical) and 55% for cadaveric allografts, while the patient survival rates were 97% and 87%, respectively, in the same period. Morbidity rates (expressed as the number of days spent in hospital) for recipients of allografts from living related donors were approximately 50% of those for recipients of cadaveric grafts. Complications in the living related donors were minimal, and acceptable. It is concluded that transplantation of allografts from living related donors has many advantages over transplantation of cadaveric kidneys, and is a valuable adjunct to a cadaveric renal transplantation programme. Greater use of living related kidney donors should be encouraged in Australia.