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Development and Sensitivity Analysis of Steady-State and Transient Ogallala Aquifer Ground-Water Flow and Particle Tracking Models
Ground-water flow and transport models of the Ogallala aquifer were constructed and calibrated for the northeastern portion of the Southern High Plains to evaluate the spatial distribution and magnitude of recharge and ground-water flow and contaminant transport. The U.S. Department of Energy's Pantex Plant, near the center of the model area, was the primary focus of this study. Concerns about potential contamination of the Ogallala aquifer from activities at the Pantex Plant have necessitated this modeling effort to better understand the hydrogeologic processes controlling ground-water flow to and within the Ogallala aquifer.
An extensive literature review synthesized previous recharge hypotheses in an effort to develop an accurate conceptual model of recharge to the Ogallala aquifer. Most of these studies designated playas as either one of several possible areas of recharge or as the primary focal point of recharge to the Ogallala aquifer. The database of geologic, geomorphic, geophysical, hydrologic, hydrochemical, and pedologic information supporting this hypothesis is extensive and expanding. Historically, several published ground-water flow models, which were constructed primarily for water-resource evaluation, used spatially uniform recharge. However, contaminant transport velocities associated with focused recharge through playas were found to be significantly higher than those associated with spatially uniform recharge.Bureau of Economic Geolog
Post-Ablation Cavity Evaluation: A Prospective Multicenter Observational Clinical Study to Evaluate Hysteroscopic Access to the Uterine Cavity 4 Years after Water Vapor Endometrial Ablation for the Treatment of Heavy Menstrual Bleeding
Study Objective: Patients who have undergone endometrial ablation may present a diagnostic challenge when they subsequently
develop vaginal bleeding, pelvic pain, or postmenopausal bleeding. Extensive scarring of the uterine cavity often
precludes evaluation and/or conservative treatment. For further research on this topic, we performed hysteroscopic examination
in study subjects a mean duration of 4 years after they had undergone water vapor endometrial ablation.
Design: Prospective, multicenter, observational clinical study.
Setting: Eight private practice or outpatient sites in the United States and Mexico.
Patients: Seventy subjects who had completed their 36-month follow-up in the AEGEA Pivotal Trial.
Interventions: Diagnostic hysteroscopy.
Measurements and Main Results: The subjects were screened for general health and infection and underwent diagnostic
hysteroscopy. Menstrual bleeding status was recorded. The video of the hysteroscopic examination was analyzed by an
independent reviewer, who assessed uterine cavity access and visualization of the cornua and tubal ostia as well as characterized
adhesions on the basis of the criteria by March et al. An independent reviewer also subjectively assessed whether
Pipelle endometrial biopsy or intrauterine device placement would be feasible. Uterine cavity access was achieved in 90%
(63/70) of subjects. Among subjects with cavity access, the cornua and ostia were visualized in 79% (50/63) and adhesions
were absent in 75% (47/63), with only 2 women having severe adhesions (3%, 2/63). Biopsy was projected to be feasible in
86% (62/70) and intrauterine device placement in 60% (42/70) of all subjects. The subjects’ bleeding statuses were not correlated
with uterine cavity access. The results were consistent for subjects with large uterine cavities and International Federation
of Gynecologic and Obstetrics type II to VI myomas ≤4 cm.
Conclusion: Water vapor endometrial ablation preserved an accessible uterine cavity and visualization of the ostia in most
subjects, with minimal incidence of severe adhesions, a mean of 4 years after the ablation procedure
12-Month Outcomes of the US Patient Cohort in the SONATA Pivotal IDE Trial of Transcervical Ablation of Uterine Fibroids.
Objective: The prospective SONATA pivotal Investigational Device Exemption (IDE) trial was performed in the United States (US) and Mexico to examine the safety and effectiveness of transcervical fibroid ablation (TFA) in the treatment of symptomatic uterine fibroids. This is an analysis of 12-month clinical outcomes in the US cohort.
Methods: TFA with the Sonata System was performed on women with symptomatic uterine fibroids. The 12-month co-primary endpoints were reduction in menstrual blood loss and freedom from surgical reintervention. Symptom severity, quality of life, patient satisfaction, safety, and reductions in uterine and fibroid volumes were also evaluated.
Results: One hundred twenty-five patients were enrolled and treated in the US. Both co-primary endpoints were achieved in this US-based cohort, as 65.3% of patients reported ≥50% reduction in menstrual bleeding and 99.2% of patients were free from surgical reintervention. Symptom improvement was noted by 97.4% of patients and 98.3% were satisfied. Ninety-five percent of patients reported reduced menstrual bleeding at 12 months, and 86.8% noted \u3e20% reduction. Significant mean improvements at 12 months were realized in both symptom severity and health-related quality of life (33.8 points and 45.8 points, respectively; all P\u3c0.0001). Mean maximal fibroid volume reduction per patient was 63.8%. There was a 0% incidence of device related adverse events. Mean length of stay was 2.5 hrs and 50% of patients returned to normal activity within 1 day.
Conclusion: This analysis of US patients in the SONATA pivotal IDE trial demonstrates results consistent with those in the full cohort. TFA with Sonata significantly reduced fibroid symptoms with a low surgical reintervention rate through 12 months. These results support the efficacy and safety of the Sonata system as a first-line treatment for women affected by symptomatic uterine fibroids
The inpatient burden of abdominal and gynecological adhesiolysis in the US
<p>Abstract</p> <p>Background</p> <p>Adhesions are fibrous bands of scar tissue, often a result of surgery, that form between internal organs and tissues, joining them together abnormally. Postoperative adhesions frequently occur following abdominal surgery, and are associated with a large economic burden. This study examines the inpatient burden of adhesiolysis in the United States (i.e., number and rate of events, cost, length of stay [LOS]).</p> <p>Methods</p> <p>Hospital discharge data for patients with primary and secondary adhesiolysis were analyzed using the 2005 Healthcare Cost and Utilization Project's Nationwide Inpatient Sample. Procedures were aggregated by body system.</p> <p>Results</p> <p>We identified 351,777 adhesiolysis-related hospitalizations: 23.2% for primary and 76.8% for secondary adhesiolysis. The average LOS was 7.8 days for primary adhesiolysis. We found that 967,332 days of care were attributed to adhesiolysis-related procedures, with inpatient expenditures totaling 1.4 billion for primary adhesiolysis; 220 million in attributable costs.</p> <p>Conclusions</p> <p>Adhesiolysis remain an important surgical problem in the United States. Hospitalization for this condition leads to high direct surgical costs, which should be of interest to providers and payers.</p
Analysis of the adoption of security headers in HTTP.
With the increase in the number of threats within Web-based systems, a more integrated approach is required to ensure the enforcement of security policies from the server to the client. These policies aim to stop man-in-the-middle attacks, code injection, and so on. This paper analyses some of the newest security options used within HTTP responses, and scans the Alexa Top 1 Million sites for their implementation within HTTP responses. These options scanned for include: Content Security Policy (CSP); Public Key Pinning Extension for HTTP (HPKP); HTTP Strict Transport Security (HSTS) and HTTP Header Field X-Frame-Options (XFO), in order to understand the impact that these options have on the most popular Web sites.The results show that, while the implementation of the parameters are increasing, they are still not implemented on many of the top sites. Along with this the paper shows the profile of adoption of Let’s Encrypt digital certificates across the one million sites, along with a way of assessing the quality of the security headers
PEXO : a global modeling framework for nanosecond timing, microsecond astrometry, and μm/s radial velocities
54 pages, 2 tables, 19 figures, accepted for publication in ApJS, PEXO is available at https://github.com/phillippro/pexoThe ability to make independent detections of the signatures of exoplanets with complementary telescopes and instruments brings a new potential for robust identification of exoplanets and precision characterization. We introduce PEXO, a package for Precise EXOplanetology to facilitate the efficient modeling of timing, astrometry, and radial velocity data, which will benefit not only exoplanet science but also various astrophysical studies in general. PEXO is general enough to account for binary motion and stellar reflex motions induced by planetary companions and is precise enough to treat various relativistic effects both in the solar system and in the target system. We also model the post-Newtonian barycentric motion for future tests of general relativity in extrasolar systems. We benchmark PEXO with the pulsar timing package TEMPO2 and find that PEXO produces numerically similar results with timing precision of about 1 ns, space-based astrometry to a precision of 1{\mu}as, and radial velocity of 1 {\mu}m/s and improves on TEMPO2 for decade-long timing data of nearby targets, due to its consideration of third-order terms of Roemer delay. PEXO is able to avoid the bias introduced by decoupling the target system and the solar system and to account for the atmospheric effects which set a practical limit for ground-based radial velocities close to 1 cm/s. Considering the various caveats in barycentric correction and ancillary data required to realize cm/s modeling, we recommend the preservation of original observational data. The PEXO modeling package is available at GitHub (https://github.com/phillippro/pexo).Peer reviewe
Rationale, design and methods for a community-based study of clustering and cumulative effects on chronic disease process and their effects on ageing: the Busselton healthy ageing study
Background: The global trend of increased life expectancy and increased prevalence of chronic and degenerative diseases will impact on health systems. To identify effective intervention and prevention strategies, greater understanding of the risk factors for and cumulative effects of chronic disease processes and their effects on function and quality of life is needed. The Busselton Healthy Ageing Study aims to enhance understanding of ageing by relating the clustering and interactions of common chronic conditions in adults to function. Longitudinal (3–5 yearly) follow-up is planned. Methods/design: Phase I (recruitment) is a cross-sectional community-based prospective cohort study involving up to 4,000 ‘Baby Boomers’ (born from 1946 to 1964) living in the Busselton Shire, Western Australia. The study protocol involves a detailed, self-administered health and risk factor questionnaire and a range of physical assessments including body composition and bone density measurements, cardiovascular profiling (blood pressure, ECG and brachial pulse wave velocity), retinal photography, tonometry, auto-refraction, spirometry and bronchodilator responsiveness, skin allergy prick tests, sleep apnoea screening, tympanometry and audiometry, grip strength, mobility, balance and leg extensor strength. Cognitive function and reserve, semantic memory, and pre-morbid intelligence are assessed. Participants provide a fasting blood sample for assessment of lipids, blood glucose, C-reactive protein and renal and liver function, and RNA, DNA and serum are stored. Clinically relevant results are provided to all participants. The prevalence of risk factors, symptoms and diagnosed illness will be calculated and the burden of illness will be estimated based on the observed relationships and clustering of symptoms and illness within individuals. Risk factors for combinations of illness will be compared with those for single illnesses and the relation of combinations of illness and symptoms to cognitive and physical function will be estimated. Discussion: This study will enable a thorough characterization of multiple disease processes and their risk factors within a community-based sample of individuals to determine their singular, interactive and cumulative effects on ageing. The project will provide novel cross-sectional data and establish a cohort that will be used for longitudinal analyses of the genetic, lifestyle and environmental factors that determine whether an individual ages well or with impairment
Erythroid-Specific Transcriptional Changes in PBMCs from Pulmonary Hypertension Patients
Gene expression profiling of peripheral blood mononuclear cells (PBMCs) is a powerful tool for the identification of surrogate markers involved in disease processes. The hypothesis tested in this study was that chronic exposure of PBMCs to a hypertensive environment in remodeled pulmonary vessels would be reflected by specific transcriptional changes in these cells.The transcript profiles of PBMCs from 30 idiopathic pulmonary arterial hypertension patients (IPAH), 19 patients with systemic sclerosis without pulmonary hypertension (SSc), 42 scleroderma-associated pulmonary arterial hypertensio patients (SSc-PAH), and 8 patients with SSc complicated by interstitial lung disease and pulmonary hypertension (SSc-PH-ILD) were compared to the gene expression profiles of PBMCs from 41 healthy individuals. Multiple gene expression signatures were identified which could distinguish various disease groups from controls. One of these signatures, specific for erythrocyte maturation, is enriched specifically in patients with PH. This association was validated in multiple published datasets. The erythropoiesis signature was strongly correlated with hemodynamic measures of increasing disease severity in IPAH patients. No significant correlation of the same type was noted for SSc-PAH patients, this despite a clear signature enrichment within this group overall. These findings suggest an association of the erythropoiesis signature in PBMCs from patients with PH with a variable presentation among different subtypes of disease.In PH, the expansion of immature red blood cell precursors may constitute a response to the increasingly hypoxic conditions prevalent in this syndrome. A correlation of this erythrocyte signature with more severe hypertension cases may provide an important biomarker of disease progression
Measurement of associated Z plus charm production in proton-proton collisions at root s=8TeV
A study of the associated production of a Z boson and a charm quark jet (Z + c), and a comparison to production with a b quark jet (Z + b), in pp collisions at a centre-of-mass energy of 8 TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 fb(-1), collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with pT(l) > 20 GeV, vertical bar eta(l)vertical bar 25 GeV and vertical bar eta(jet)vertical bar Z + c + X) B(Z -> l(+)l(-)) = 8.8 +/- 0.5 (stat)+/- 0.6 (syst) pb. The ratio of the Z+c and Z+b production cross sections is measured to be sigma(pp -> Z+c+X)/sigma (pp -> Z+b+X) = 2.0 +/- 0.2 (stat)+/- 0.2 (syst). The Z+c production cross section and the cross section ratio are also measured as a function of the transverse momentum of theZ boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.Peer reviewe
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