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An Investigation of the Natural and Anthropogenic Contributions of Arsenic to Urban Fill Soil
Arsenic in urban/historic fill soil, originating from both natural and anthropogenic sources, is a continuing concern from a human health risk point of view. This concern is heightened in urban gardens where the soil is to be used for growing vegetables for consumption.
The presentation explores the origin of arsenic present in New England urban/historic fill soil and will derive an understanding of the relative contribution of the natural and anthropogenic components using available data sets. These data sets include more than 5,000 urban soil samples from the Central Artery/Tunnel Project in Boston statistically analyzed using ProUCL 4.0. Data also includes more than 2,700 samples of a natural/rural background data set from a comprehensive study of rock and stream sediment arsenic in New England analyzed by the U.S. Geological Survey (USGS), supported by other available data sets resulting in a broad base of up to approximately 10,000 individual sample results. These multiple data sets will be reviewed and summarized such that there are a mean/median and upper values presented for natural soils and rocks and a mean/median and upper values presented for anthropogenic impacted soils, with and without outliers. From this compilation will be derived an understanding of the numerical differential between them. Finally, we will apply standard human health risk calculations, provided by the Massachusetts Department of Environmental Protection (MassDEP), to illustrate the magnitude of potential effects of the natural soil and the anthropogenic–containing soil. The derived mean, median, and upper percentage values will be considered in the context of the human health risk assessment calculations. In conclusion, the exercise will identify the risk significance of the anthropogenic contribution relative to the natural soil and provide an understanding of the overall affect associated with background in the urban environment
THEMATIC ANALYSIS FOR THE LOSS OF ENHANCED IMAGING CAPABILITIES ON COAST GUARD MH-65 SEARCH AND RESCUE ASSETS
This study answers the following research questions: what policies and procedures within United States Coast Guard Acquisitions, as well as external factors, may have contributed to the failed sustainment of the Electro-Optical Sensor System (ESS) and the critical capability it provides? And what process changes could be implemented to prevent similar capability loss? This thematic case analysis explores how the ESS was lost and what acquisition-related decisions and processes ultimately contributed to the removal of the ESS without a viable replacement in hand. It also provides a quantitative analysis of the impact the removal of the ESS had on Coast Guard search and rescue operations. Our findings suggest that the loss of the ESS on the MH-65 was a consequence of the segregation of responsibilities between the program’s acquisitions and its sustainment resulting in the system being overlooked and the Coast Guard being caught unprepared by the end-of-life notification from Teledyne/FLIR in 2019. This analysis results in initial insights, recommendations, and potential acquisition policy improvements that can be applied to enhance the Coast Guard’s ability to sustain key aviation capabilities long-term and prevent similar scenarios in the future.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Commander, United States Coast GuardLieutenant Commander, United States Coast GuardEnsign, United States Nav
vitamin C, aging and Alzheimer's disease
Accumulating evidence in mice models of accelerated senescence indicates a rescuing role of ascorbic acid in premature aging. Supplementation of ascorbic acid appeared to halt cell growth, oxidative stress, telomere attrition, disorganization of chromatin, and excessive secretion of inflammatory factors, and extend lifespan. Interestingly, ascorbic acid (AA) was also found to positively modulate inflamm-aging and immunosenescence, two hallmarks of biological aging. Moreover, ascorbic acid has been shown to epigenetically regulate genome integrity and stability, indicating a key role of targeted nutrition in healthy aging. Growing in vivo evidence supports the role of ascorbic acid in ameliorating factors linked to Alzheimer’s disease (AD) pathogenesis, although evidence in humans yielded equivocal results. The neuroprotective role of ascorbic acid not only relies on the general free radical trapping, but also on the suppression of pro-inflammatory genes, mitigating neuroinflammation, on the chelation of iron, copper, and zinc, and on the suppression of amyloid-beta peptide (Aβ) fibrillogenesis. Epidemiological evidence linking diet, one of the most important modifiable lifestyle factors, and risk of Alzheimer's disease is rapidly increasing. Thus, dietary interventions, as a way to epigenetically modulate the human genome, may play a role in the prevention of AD. The present review is aimed at providing an up to date overview of the main biological mechanisms that are associated with ascorbic acid supplementation/bioavailability in the process of aging and Alzheimer’s disease. In addition, we will address new fields of research and future directions.</jats:p
Resistin: A reappraisal
Abstract From a biological point of view, aging can be considered a progressive inability of an organism to react to stress, maintain homeostasis, and survive unfavourable changes during post-maturational life. The expression of several adipokines changes during aging and for some changes, a role in the onset of chronic disease and frailty has been proposed. Among adipokines, resistin was shown in recent studies to play a key role in aging. Resistin is a small secreted protein that regulates glucose metabolism in mammalians. High resistin levels induce insulin resistance and exert proinflammatory effects. Consistently, resistin has been shown to play a pivotal role in various metabolic, inflammatory, and autoimmune diseases. Herein, the role of resistin as a molecular link between aging and age-related conditions was reviewed and the clinical implications of this knowledge discussed
Follicular proliferation TIR3B. The role of total thyroidectomy vs lobectomy
Background: TIR3B thyroid nodules are considered to be at risk of malignancy (15-30%) but guidelines recommend conservative surgery with lobectomy with primary diagnostic porpoise. Risk stratification mainly based on ultrasound, elastography and genetic mutations usually may influences the surgical approach. Methods: We retrospectively analyzed 52 cases of TIR3B underwent between 2015 and 2017 total thyroidectomy (TT) and lobectomy (L), focusing mainly on the observed rate of malignancy. Chi-squared test and Fisher's exact probability test were used for analysis, considering a P values less than 0.05 as significant. Results: Out of 52 patients 49 underwent TT and 3 L. In TT group a multinodular goiter was associated in 67.3% of patients. Malignancy rate was 81.6 and 33.3% respectively after TT and L (P 0.003). Multicentric and contralateral tumors were detected respectively in 36.7% and in 32.6% of patients underwent TT. No main post-operative complications were registered. Conclusions: Ultrasound and elastography are useful to define within the TIR3B group those lesions at higher risk and therefore requiring a more radical approach. TT seems an appropriate approach to TIR3B lesions, especially in multinodular goiter, considering the incidence of malignancy with probably higher rate than previously reported
The OPERA magnetic spectrometer
The OPERA neutrino oscillation experiment foresees the construction of two
magnetized iron spectrometers located after the lead-nuclear emulsion targets.
The magnet is made up of two vertical walls of rectangular cross section
connected by return yokes. The particle trajectories are measured by high
precision drift tubes located before and after the arms of the magnet.
Moreover, the magnet steel is instrumented with Resistive Plate Chambers that
ease pattern recognition and allow a calorimetric measurement of the hadronic
showers. In this paper we review the construction of the spectrometers. In
particular, we describe the results obtained from the magnet and RPC prototypes
and the installation of the final apparatus at the Gran Sasso laboratories. We
discuss the mechanical and magnetic properties of the steel and the techniques
employed to calibrate the field in the bulk of the magnet. Moreover, results of
the tests and issues concerning the mass production of the Resistive Plate
Chambers are reported. Finally, the expected physics performance of the
detector is described; estimates rely on numerical simulations and the outcome
of the tests described above.Comment: 6 pages, 10 figures, presented at the 2003 IEEE-NSS conference,
Portland, OR, USA, October 20-24, 200
Male breast cancer, clinical presentation, diagnosis and treatment: Twenty years of experience in our Breast Unit
BACKGROUND: The male breast cancer (MBC) is a rare and represents less than 1% of all malignancies in men and only 1% of all breast cancers incident. We illustrate the experience of our team about the clinico-pathological characteristics, treatment and prognostic factors of patients treated over a period of twenty years . RESULTS: Forty-seven patients were collected 1995-2014 at the Breast Unit of the Hospital of Terni, Italy. The average age was 67 years and the median time to diagnosis from the onset of symptoms was 16 months. The main clinical complaint was sub areolar swelling in 36, 76% of cases. Most patients have come to our attention with advanced disease. The histology of about ninety percent of the tumors were invasive ductal carcinoma. Management consisted mainly of radical mastectomy; followed by adjuvant radiotherapy and hormonal therapy with or without chemotherapy. The median follow-up was 38 months. The evolution has been characterized by local recurrences; in eight cases (17% of all patients). Metastasis occurred in 15 cases (32% of all patients). The site of bone metastases was in eight cases; lung in four cases; liver in three cases; liver and skin in one case and pleura and skin in one case. CONCLUSION: The male breast cancer has many similarities to breast cancer in women, but there are distinct functions that need to be appreciated. Future research for a better understanding of the disease should provide a better account of genetic and epigenetic characteristics of these forms; but, above all, epidemiological and biological cohorts numerically more consistent
Characterization of digital-micromirror device-based infrared scene projector
A test procedure is developed for an infrared laser scene projector, and applied to a projection system that we develop based on digital micromirror technology. The intended use will be for simulation and target training. Resolution and noise are significant parameters for target perception models of infrared imaging systems. System resolution is normally measured as the modulation transfer function (MTF), and its noise modeled through an appropriate signal standard deviation metric. We compare MTF measurements for both mid-wave (MWIR) and longwave IR (LWIR) bands for an infrared laser scene projector based on the digital micromirror device (DMD). Moreover, we use two complimentary models to characterize imaging camera noise. This provides a quantitative image-quality criterion of system performance
Design, fabrication, and characterization of antenna-coupled metal-oxide-metal diodes for dual-band detection
Two designs for antenna-coupled Ni-NiO-Ni diodes are fabricated and tested for dual-band detection in the millimeter-wave (MMW), 94-GHz, and infrared (IR), 28.3-THz, frequencies. The detector noise, antenna receiving properties, and noise equivalent power (NEP) are measured. The simultaneous dual-band response is verified
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