Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-25
... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-74,327] Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division of Wellpoint, Inc., Green Bay, WI; Notice... former workers of Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-07
.../B/A/Anthem Blue Cross & Blue Shield, et al.; Amended Certification Regarding Eligibility To Apply for Worker Adjustment Assistance TA-W-74,895 Wellpoint, Inc. D/B/A/Anthem Blue Cross & Blue Shield... Enterprise Provider Data Management Team North Haven, Connecticut TA-W-74,895F Wellpoint, Inc. D/B/A/Blue...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-25
.../B/A/Anthem Blue Cross & Blue Shield Enterprise Provider Data Management Team Including On-Site... & Blue Shield, Enterprise Provider Data Management Team, Including On-Site Leased Workers From Kelly... Of Kentucky, Enterprise Provider Data Management Team, Louisville, Kentucky TA-W-74,895B Wellpoint...
Goldberg, L G; Greenberg, W
1979-10-01
The health maintenance organization (HMO) can provide an alternative to the predominant form of health care delivery in the United States, fee-for-service. Although market penetration of the HMO is relatively low in most parts of the country, the HMO has achieved a significant market share in a number of states. This paper examines the competitive response of Blue Cross and Blue Shield to the introduction of the HMO in two geographic regions with significant HMO activity, northern California and Hawaii. The evidence obtained from extensive interviews indicates that Blue Cross and Blue Shield plans have responded to HMO competitive pressure by establishing their own HMOs and by altering traditional procedures. HMO competition has stimulated Blue Cross and Blue Shield to make greater cost control efforts and to offer larger benefit packages. These results can have important policy implications for the role that HMOs are to play in cost containment.
ERIC Educational Resources Information Center
Saint Louis Community Coll., MO.
The 18-month Skills Today for Advancement Tomorrow (STAT) program, a partnership among St. Louis Community College, the St. Louis Public Schools' Adult Basic Education Program, and Blue Cross and Blue Shield of Missouri, had the following objectives: (1) provide counseling and training for 370 current Blue Cross and Blue Shield workers; (2)…
Use of big data by Blue Cross and Blue Shield of North Carolina.
Helm-Murtagh, Susan C
2014-01-01
The health care industry is grappling with the challenges of working with and analyzing large, complex, diverse data sets. Blue Cross and Blue Shield of North Carolina provides several promising examples of how big data can be used to reduce the cost of care, to predict and manage health risks, and to improve clinical outcomes.
Code of Federal Regulations, 2014 CFR
2014-10-01
... “intermediary” also means a Blue Cross plan that has entered into a subcontract approved by CMS with the Blue Cross and Blue Shield Association to perform intermediary functions. [71 FR 68228, Nov. 24, 2006] ...
Code of Federal Regulations, 2012 CFR
2012-10-01
... “intermediary” also means a Blue Cross plan that has entered into a subcontract approved by CMS with the Blue Cross and Blue Shield Association to perform intermediary functions. [71 FR 68228, Nov. 24, 2006] ...
Code of Federal Regulations, 2013 CFR
2013-10-01
... “intermediary” also means a Blue Cross plan that has entered into a subcontract approved by CMS with the Blue Cross and Blue Shield Association to perform intermediary functions. [71 FR 68228, Nov. 24, 2006] ...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-16
........ May 30, 2011. Shield of Maine, WellPoint, Inc., Enterprise Business Services, Aerotek, etc. 81,664A Anthem Blue Cross Blue Manchester, NH......... May 30, 2011. Shield of New Hampshire, WellPoint, Inc..., 2011. Shield of Connecticut, WellPoint, Inc., Enterprise Business Services, Aerotek, etc. 81,710 Sun...
Edlich, Richard F
2005-01-01
The Commonwealth of Virginia has a disorganized approach to enrolling their retired faculty in Medicare Supplement Insurance Programs. An organized approach to establishing Medicare Supplemental Insurance for retired University faculty should include the following administrative changes to correct this potential health-care crisis for retired state faculty members. First, the ombudsman for human resources for the state universities must receive educational programs that prepare the retired faculty members over the age of 65 to select the corporate insurance policy from Anthem Blue Cross/Blue Shield Insurance Company. Included in this educational program should be a review of the Advantage 65 Member Handbook. Second, they must point out to the faculty member that they are receiving a CORPORATE insurance policy rather than an individual insurance policy from Anthem Blue Cross/Blue Shield Insurance Company. They must provide the telephone numbers of the Anthem Blue Cross/Blue Shield offices in Roanoke, Virginia. Concomitantly, they must send the name and address of the faculty member to the Commonwealth of Virginia Department of Human Resource Management. They should inform the faculty member that the Commonwealth of Virginia Department of Human Resource Management will be sending them newsletters that outline any changes in the corporate insurance policy that they coordinate with the Anthem Blue Cross/Blue Shield Insurance Company. The Commonwealth of Virginia Department of Human Resource Management must take on some new responsibilities in their efforts to coordinate health-care coverage of the retired faculty over the age of 65. First, they must have a computer registry of all corporate health-care policies of the individual faculty members to ensure that newsletters are being sent to them. Ideally, this agency should have a computerized system that allows it to send out its newsletter update by email to those retired faculty members who have computers. They should urge the faculty members to initiate an automatic check payment withdrawal from their bank so that the premiums from their corporate insurance policy can be paid promptly to Anthem Blue Cross/Blue Shield Insurance Company. Whereas the universities and the Commonwealth of Virginia Department of Human Resource Management are making these responsible changes, Anthem Blue Cross/Blue Shield Insurance Company must undertake innovative changes in their corporate health-care policy to assist the retired faculty member. For instance, they must list on the insurance card that the faculty member has a corporate policy. Like the United Health Insurance Company, it would be advisable to offer a 2-5% reduction in the cost of the corporate insurance policy if the faculty member begins an automatic premium payment agreement through their bank. This insurance discount would be an added incentive for the faculty member to do automatic payments through their bank.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-17
... Montana residents a high-quality option for their health insurance, routinely pressuring Blue Cross to... reputation for high-quality customer service. 36. Since the Agreement was announced in August 2011, many... offered Montana residents a high-quality option for their health insurance, routinely pressuring Blue...
Share, David A; Mason, Margaret H
2012-09-01
Blue Cross Blue Shield of Michigan partnered with providers across the state to create an innovative, "fee for value" physician incentive program that would deliver high-quality, efficient care. The Physician Group Incentive Program rewards physician organizations-formal groups of physicians and practices that can accept incentive payments on behalf of their members-based on the number of quality and utilization measures they adopt, such as generic drug dispensing rates, and on their performance on these measures across their patient populations. Physicians also receive payments for implementing a range of patient-centered medical home capabilities, such as patient registries, and they receive higher fees for office visits for incorporating these capabilities into routine practice while also improving performance. Taken together, the incentive dollars, fee increases, and care management payments amount to a potential increase in reimbursement of 40 percent or more from Blue Cross Blue Shield of Michigan for practices designated as high-performing patient-centered medical homes. At the same time, we estimate that implementing the patient-centered medical home capabilities was associated with $155 million in lower medical costs in program year 2011 for Blue Cross Blue Shield of Michigan members. We intend to devote a higher percentage of reimbursement over time to communities of caregivers that offer high-value, system-based care, and a lower percentage of reimbursement to individual physicians on a service-specific basis.
Blues plans trying to extract better deals from hospitals.
Kenkel, P J
1992-08-17
Stung by recent reports indicating that several health insurance plans sponsored by the Blue Cross and Blue Shield Association may be on the brink of insolvency, some Blues plans are putting the squeeze on hospitals by demanding better prices. The Blues are getting tougher with hospitals because they want to slow the increases in their customers' medical bills.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-23
...Point, Inc., Empire Middletown, NY........ June 5, 2011. Blue Cross and Blue Shield Division, Kelly... the petitioning groups of workers are covered by active certifications. Consequently, further...
Healthcore (Wellpoint/Blue Cross/Blue Shield)
Healthcore uses data from health plan providers, patient-reported outcomes, and clinical investigators to assist with studies on safety, efficacy, effectiveness, compliance and the economic impact of pharmaceuticals, biotechnologies, and devices on real-world health outcomes.
42 CFR 440.330 - Benchmark health benefits coverage.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Benchmark-Equivalent Coverage § 440.330 Benchmark health benefits coverage. Benchmark coverage is health...) Federal Employees Health Benefit Plan Equivalent Coverage (FEHBP—Equivalent Health Insurance Coverage). A benefit plan equivalent to the standard Blue Cross/Blue Shield preferred provider option service benefit...
42 CFR 440.330 - Benchmark health benefits coverage.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Benchmark-Equivalent Coverage § 440.330 Benchmark health benefits coverage. Benchmark coverage is health...) Federal Employees Health Benefit Plan Equivalent Coverage (FEHBP—Equivalent Health Insurance Coverage). A benefit plan equivalent to the standard Blue Cross/Blue Shield preferred provider option service benefit...
42 CFR 440.330 - Benchmark health benefits coverage.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Benchmark-Equivalent Coverage § 440.330 Benchmark health benefits coverage. Benchmark coverage is health...) Federal Employees Health Benefit Plan Equivalent Coverage (FEHBP—Equivalent Health Insurance Coverage). A benefit plan equivalent to the standard Blue Cross/Blue Shield preferred provider option service benefit...
42 CFR 440.330 - Benchmark health benefits coverage.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Benchmark-Equivalent Coverage § 440.330 Benchmark health benefits coverage. Benchmark coverage is health...) Federal Employees Health Benefit Plan Equivalent Coverage (FEHBP—Equivalent Health Insurance Coverage). A benefit plan equivalent to the standard Blue Cross/Blue Shield preferred provider option service benefit...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-24
... Blue Cross Blue Salt Lake City, UT.... 02/09/11 02/08/11 Shield (State/One-Stop). 75198 ACS Outsourcing........... 02/11/11 02/10/11 (State/One-Stop). 75218 International Automotive Lebanon, VA 02/11/11 02/09/11...
ERIC Educational Resources Information Center
Eppolito, Antonio; And Others
1995-01-01
BEL, a partnership involving Blue Cross/Blue Shield of Central New York, a Syracuse elementary school, and Le Moyne College, provides an effective, low-cost, individually tailored supplemental reading program allowing poor readers to catch up with their classmates. Le Moyne supplies undergraduate tutors and a van; the insurance company provides…
Capture and culture: organizational identity in New York Blue Cross.
Brown, L D
1991-01-01
This article explores the changing corporate culture of New York's Blue Cross and Blue Shield plan in its first fifty years. As the plan grew, corporate culture evolved over four sequential phases: the plan first had the character of an experiment, then that of a movement, a business, and, most recently, a corporate agglomerate. Accompanying this evolution has been an identity crisis, as the need to adapt to a turbulent environment has challenged the plan's settled understanding of its core values, namely, voluntarism, community, and cooperation.
Benko, Laura B
2004-05-17
It's been a strained few months at Blue Cross and Blue Shield of Rhode Island. Outrage over corporate excess led to a flurry of reforms at the insurer, headed by Chairman Frank Montanaro, left, including banning loans to employees and dropping lavish perks. Other Blues have been catching flak for their burgeoning bottom lines, but executives say they need ample reserves since that's their only capital.
Benko, Laura B
2006-08-07
The Blue Cross and Blue Shield Association was touting its plans' devotion to transparency last week, unveiling a database offering insight into a variety of healthcare trends. But some are doubting the Blues' sincerity, given the association's decision to withhold aggregate plan financial results. "It seems very inconsistent with their new emphasis on transparency and empowering people with information," says Bruce McPherson, left.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-01
... AMA is the largest association of physicians and medical students in the United States. The AMA's...-29656] Dear Mr. Soven: On behalf of the physician and medical student members of the American Medical... robust competition within the market than existed before the Agreement. Given the weak state of health...
Choe, Hae Mi; Lin, Alexandra Tungol; Kobernik, Kathleen; Cohen, Marc; Wesolowicz, Laurie; Qureshi, Nabeel; Leyden, Tom; Share, David A; Darland, Rozanne; Spahlinger, David A
2018-04-01
Inappropriate drug use, increasing complexity of drug regimens, continued pressure to control costs, and focus on shared accountability for clinical measures drive the need to leverage the medication expertise of pharmacists in direct patient care. A statewide strategy based on the collaboration of pharmacists and physicians regarding patient care was developed to improve disease state management and medication-related outcomes. Blue Cross Blue Shield of Michigan (BCBSM) partnered with Michigan Medicine to develop and implement a statewide provider-payer program called Michigan Pharmacists Transforming Care and Quality (MPTCQ), which integrates pharmacists within physician practices throughout the state of Michigan. As the MPTCQ Coordinating Center, Michigan Medicine established an infrastructure integrating clinical pharmacists into direct patient care within patient-centered medical home (PCMH) practices and provides direction and guidance for quality and process improvement across physician organizations (POs) and their affiliated physician practices. The primary goal of MPTCQ is to improve patient care and outcomes related to Medicare star ratings and HEDIS measures through integration of clinical pharmacists into direct patient care. The short-term goal is to adopt and modify Michigan Medicine's integrated pharmacist practice model at participating POs, with the long-term goal of developing a sustainable model of pharmacist integration at each PO to improve patient care and outcomes. Initially, pharmacists are delivering disease management (diabetes, hypertension, and hyperlipidemia) and comprehensive medication review services with future plans to expand clinical services. In 2015, 10 POs participated in year 1 of the program. In collaboration with the MPTCQ Coordinating Center, each PO identified 1 "pharmacist transformation champion" (PTC). The PTC implemented the integrated pharmacist model at 2 or 3 practice sites with at least 2 practicing physicians per site. MPTCQ is a unique collaboration between a large academic institution, physician organizations, a payer, and a statewide coordinating center to improve patient care and address medication-related challenges by integrating pharmacists into a PCMH network. Pharmacists can actively provide their medication expertise to physicians and patients and optimize quality measure performance. This project was funded by Blue Cross Blue Shield of Michigan. Choe and Spahlinger are employees of Michigan Medicine. Tungol Lin, Kobernik, Cohen, Qureshi, Leyden, and Darland are employees of Blue Cross Blue Shield of Michigan. At the time of manuscript preparation, Share and Wesolowicz were employees of Blue Cross Blue Shield of Michigan. Study concept and design were primarily contributed by Choe, along with the other authors. Choe, Tungol Lin, and Kobernik collected data, and data interpretation was performed by Choe, Tungol Lin, Cohen, and Wesolowicz. The manuscript was written primarily by Choe, along with Tungol Lin and assisted by Kobernik, Cohen, Leyden, and Qureshi. The manuscript was revised by Leyden, Spahlinger, Share, and Darland. Material from this manuscript was previously presented as an education session at the 2016 AMCP Managed Care & Specialty Pharmacy Annual Meeting; April 19-22, 2016; San Francisco, California.
The Many Elements of Cost Control
McNerney, Walter J.
1980-01-01
For Blue Cross and Blue Shield Plans, cost containment is not a new concern but an activity that has been carried on for years. It has now been given new emphasis by the urgencies of inflation and the new focus of national attention on health care costs as one of its more conspicuous phenomena—chiefly a result of the inflation but often mistaken for, and mislabeled as, a cause. PMID:7385848
Ayaki, Masahiko; Hattori, Atsuhiko; Maruyama, Yusuke; Nakano, Masaki; Yoshimura, Michitaka; Kitazawa, Momoko; Negishi, Kazuno; Tsubota, Kazuo
2016-01-01
We investigated sleep quality and melatonin in 12 adults who wore blue-light shield or control eyewear 2 hours before sleep while using a self-luminous portable device, and assessed visual quality for the two eyewear types. Overnight melatonin secretion was significantly higher after using the blue-light shield (P < 0.05) than with the control eyewear. Sleep efficacy and sleep latency were significantly superior for wearers of the blue-light shield (P < 0.05 for both), and this group reported greater sleepiness during portable device use compared to those using the control eyewear. Participants rated the blue-light shield as providing acceptable visual quality.
Lauridsen, Clara Bratt; Sanyova, Jana; Simonsen, Kim Pilkjær
2015-11-05
The pigment composition of six painted metal knight shields of the Order of the Elephant dating from the second half of the 20th century belonging to the Danish royal collection were studied using Raman microscopy. By focusing a 785 nm laser with a 50× objective on particles in paint cross sections, it was possible to identify the following 20 compounds: hematite, goethite, chrome red/orange, chrome yellow, zinc chrome yellow, carbon black, toluidine red PR3, chlorinated para red PR4, dinitroaniline orange PO5, phthalocyanine blue PB15, indanthrone blue PB60, ultramarine, Prussian blue, lead white, anatase, rutile, calcium carbonate, barium sulphate, gypsum and dolomite. The components were frequently present in complex pigment mixtures. Additional information was obtained by elemental analysis with scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) to identify cobalt blue, zinc white and cadmium red, as well as to indicate the presence of zinc white in some pigment mixtures. The study allowed a comparison between the industrially applied preparation layers and the artistic paint layers applied by the heraldic painter. Differences in the choice of paint and pigment types were observed on the earliest knight shields, demonstrating a general delay of industrial materials into artist paints. Copyright © 2015 Elsevier B.V. All rights reserved.
Moscucci, Mauro; Share, David; Kline-Rogers, Eva; O'Donnell, Michael; Maxwell-Eward, Ann; Meengs, William L; Clark, Vivian L; Kraft, Phillip; De Franco, Anthony C; Chambers, James L; Patel, Kirit; McGinnity, John G; Eagle, Kim A
2002-10-01
The past decade has been characterized by increased scrutiny of outcomes of surgical and percutaneous coronary interventions (PCIs). This increased scrutiny has led to the development of regional, state, and national databases for outcome assessment and for public reporting. This report describes the initial development of a regional, collaborative, cardiovascular consortium and the progress made so far by this collaborative group. In 1997, a group of hospitals in the state Michigan agreed to create a regional collaborative consortium for the development of a quality improvement program in interventional cardiology. The project included the creation of a comprehensive database of PCIs to be used for risk assessment, feedback on absolute and risk-adjusted outcomes, and sharing of information. To date, information from nearly 20,000 PCIs have been collected. A risk prediction tool for death in the hospital and additional risk prediction tools for other outcomes have been developed from the data collected, and are currently used by the participating centers for risk assessment and for quality improvement. As the project enters into year 5, the participating centers are deeply engaged in the quality improvement phase, and expansion to a total of 17 hospitals with active PCI programs is in process. In conclusion, the Blue Cross Blue Shield of Michigan Cardiovascular Consortium is an example of a regional collaborative effort to assess and improve quality of care and outcomes that overcome the barriers of traditional market and academic competition.
Muthappan, Palaniappan; Smith, Dean; Aronow, Herbert D.; Eagle, Kim; Wohns, David; Fox, James; Share, David; Gurm, Hitinder S.
2014-01-01
Background Percutaneous coronary intervention (PCI) is sometimes performed with the intent to lower cardiovascular risk before high‐risk noncardiac surgery (HRNCS). There are limited data on the frequency and outcome of PCIs performed in this setting. Methods and Results We assessed the frequency, characteristics, and in‐hospital outcomes of patients undergoing PCI as part of the preoperative workup for HRNCS among all 61 145 elective PCIs performed between 2002 and 2009 at 14 hospitals in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium. Propensity matching was performed to compare outcomes of patients undergoing PCI before HRNCS with all other elective PCI patients. The frequency of PCI before HRNCS was low (4.2%). Patients undergoing PCI before HRNCS were older (67.3 versus 64.9 years, P<0.0001) and had a greater burden of comorbidity. Patients undergoing PCI before HRNCS had an increase in unadjusted major adverse cardiovascular events, postprocedure transfusion, contrast‐induced nephropathy, nephropathy requiring dialysis, and same‐admission coronary artery bypass graft surgery, but there was no difference in mortality (0.27% versus 0.14%, P=0.11). However, in propensity score–matched samples, there was a significant difference only in nephropathy requiring dialysis. Conclusions The incidence of PCI performed in preparation for high‐risk noncardiac surgery is low, and these procedures are currently being performed on a highly selected high‐risk patient population. PMID:24820654
Sandstrom, Robert W; Lehman, Jedd; Hahn, Lee; Ballard, Andrew
2013-10-01
The Affordable Care Act of 2010 establishes American Health Benefit Exchanges. The benefit design of insurance plans in state health insurance exchanges will be based on the structure of existing small-employer-sponsored plans. The purpose of this study was to describe the structure of the physical therapy benefit in a typical Blue Cross Blue Shield (BCBS) preferred provider organization (PPO) health insurance plan available in the individual insurance market in 2011. A cross-sectional survey design was used. The physical therapy benefit within 39 BCBS PPO plans in 2011 was studied for a standard consumer with a standard budget. First, whether physical therapy was a benefit in the plan was determined. If so, then the structure of the benefit was described in terms of whether the physical therapy benefit was a stand-alone benefit or part of a combined-discipline benefit and whether a visit or financial limit was placed on the physical therapy benefit. Physical therapy was included in all BCBS plans that were studied. Ninety-three percent of plans combined physical therapy with other disciplines. Two thirds of plans placed a limit on the number of visits covered. The results of the study are limited to 1 standard consumer, 1 association of insurance companies, 1 form of insurance (a PPO), and 1 PPO plan in each of the 39 states that were studied. Physical therapy is a covered benefit in a typical BCBS PPO health insurance plan. Physical therapy most often is combined with other therapy disciplines, and the number of covered visits is limited in two thirds of plans.
1987-05-01
18.79 Other plastic repair of external ear Otoplasty; Postauricular skin graft ; Repair of lop ear 19.4 Myringoplasty Epitympanic, type I; Myringoplasty...of lip 27.53 Closure of fistula of mouth * 27.54 Repair of cleft lip * 27.55 Bill-thickness skin graft to lip and mouth * 27.56 Other skin graft to...structure 86.60 Free skin graft , not otherwise specified *d :935 Empire Blue Cross and Blue Shield- New York Dvisior 56 INTEGUMENTARY SYSTIA continued
The Impact of Global Budgets on Pharmaceutical Spending and Utilization
Fendrick, A. Mark; Song, Zirui; Landon, Bruce E.; Safran, Dana Gelb; Mechanic, Robert E.; Chernew, Michael E.
2014-01-01
In 2009, Blue Cross Blue Shield of Massachusetts implemented a global budget-based payment system, the Alternative Quality Contract (AQC), in which provider groups assumed accountability for spending. We investigate the impact of global budgets on the utilization of prescription drugs and related expenditures. Our analyses indicate no statistically significant evidence that the AQC reduced the use of drugs. Although the impact may change over time, early evidence suggests that it is premature to conclude that global budget systems may reduce access to medications. PMID:25500751
1981-09-01
Rizzuto, my babysitter , whose long hours everyday allowed me to attend classes without worrying about my son, Andy; and my new bride, Roz, whose love...4 - , . ~ DTIO.,=I= EIECTE~l rl 1 FEB 1-7-1982 I III O UNITED STATES AIR FORCE AIR UNI VERSITY AIR FORCE INSTITUTE OF TECHNOLOGY ...WORK UNIT NUMBERS School of Systems and Logistics Air Force Institute of Technology , WPAFB OH II. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE
The effect of provider control of Blue Shield plans on health care markets.
Arnould, R J; DeBrock, L M
1985-07-01
Blue Shield plans often are granted regulatory advantages by the states in which they operate. Run efficiently, such not-for-profit firms should use these lower costs to eliminate their less advantaged rivals, the commercial insurers. However, these higher-cost commercial providers have been able to offer insurance coverage at prices competitive with the Blues, as evidenced by the fact that Blue plans have, on average, less than 50 percent market share. Similar prices with lower overall costs implies that economic rents are being earned, rents which a not-for-profit firm cannot distribute to owners. In this paper we argue that when there are competing goals among the groups controlling the Blue Shield plans, the different possible "uses" of the regulatory advantage become endogenously determined, necessitating the use of simultaneous equation estimation. Testing this model we find the major effect of doctor-control of Blue Shield plans is to raise doctors' fees while lowering the amount of rents captured by both consumers and administrators.
Afendulis, Christopher C; Fendrick, A Mark; Song, Zirui; Landon, Bruce E; Safran, Dana Gelb; Mechanic, Robert E; Chernew, Michael E
2014-01-01
In 2009, Blue Cross Blue Shield of Massachusetts implemented a global budget-based payment system, the Alternative Quality Contract (AQC), in which provider groups assumed accountability for spending. We investigate the impact of global budgets on the utilization of prescription drugs and related expenditures. Our analyses indicate no statistically significant evidence that the AQC reduced the use of drugs. Although the impact may change over time, early evidence suggests that it is premature to conclude that global budget systems may reduce access to medications. © The Author(s) 2014.
McDonnell, Patricia; Guttenberg, Abbie; Greenberg, Leonard; Arnett, Ross H.
1986-01-01
Nationwide, 8 percent of all employment-related health plans were self-insured in 1984, which translates into more than 175,000 self-insured plans according to our latest study of independent health plans. The propensity of an organization to self-insure differs primarily by its size, with large establishments more likely to self-insure. In the overwhelming majority of cases, the self-insured benefit was hospital and/or medical. Among employers who self-insure, 23 percent self-administer, and the remaining 77 percent hire a commercial insurance company, Blue Cross/Blue Shield plan, or an independent third-party administrator to administer the health plan. PMID:10312008
Thomas, Michael P; Moscucci, Mauro; Smith, Dean E; Aronow, Herb; Share, David; Kraft, Phillip; Gurm, Hitinder S
2011-09-01
There is a paucity of data on the outcome of contemporary percutaneous coronary intervention (PCI) in the elderly. Accordingly, we assessed the impact of age on outcome of a large cohort of patients undergoing PCI in a regional collaborative registry. Increasing age is associated with a higher incidence of procedural-related complications. We evaluated the outcome of 152,373 patients who underwent PCI from 2003 to 2008 in the 31 hospitals participating in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium. The procedural outcomes of the cohort were compared by dividing patients into < 70 years of age, 70 to 79 years, 80 to 84 years, 85 to 89 years, and ≥ 90 years. Of the cohort, 64.64% were <70 years of age, 23.83% were 70 to 79 years, 7.85% were 80 to 84 years, 3.09% were 85 to 89 years, and 0.58% were 90 years or older. Increasing age was associated with an increase in all-cause in-hospital mortality, contrast-induced nephropathy, transfusion, stroke/transient ischemic attack, and vascular complications. The overall in-hospital mortality rate was 1.09% and increased from 0.67% in those younger than 70 years up to 5.44% in those 90 years old or greater. The mortality rate in patients over 80 years approached 12% to 15% for those with ST-segment myocardial infarction and 39% in cardiogenic shock patients. The proportion of elderly patients referred for PCI is increasing. Procedural complications increase with age, and patients presenting with unstable symptoms are at the highest risk. © 2011 Wiley Periodicals, Inc.
Hurricane preparedness: Current procedures at Blue Cross Blue Shield of Florida.
Devaney, Everett
2008-01-01
This paper discusses experience, methodology and recommendations for successful business continuity and disaster recovery planning for health care organisations. Hurricanes, tornadoes and other natural disasters are a regular occurrence in Florida. Low-lying coastal areas are at increased risk, with populations in inland areas as far as 200-300 miles with potential to suffer heavy damage. This case study shows how one institution, Blue Cross Blue Shield of Florida, provides and maintains emergency response plans for critical functions, services or processes before, during and after a disaster, in support of its 8.3 million customers, its stakeholders and colleagues such as providers and vendors. Even though modern tracking gives fair warning regarding hurricanes, the use of specific and tested emergency response planning is critical to allow business continuity decision-making well before disaster strikes. This study examines how functional units within a health care organisation can plan and prepare to protect the public who depend on their services and resources, as well as minimise the risk to employees and business stakeholders. Coordination of a Contingency Response Team (within the functional units) and an Enterprise Operations Centre must be well managed to minimise adverse customer service disruptions and at the same time minimise impact to the company. Decision making and communications are strictly organised to protect stakeholders, make temporary business rule changes, allow for alternative business processes and handle benefit decisions, following methodology known, tested and used in past scenarios. In summary, the paper explores key points to achieve active and engaged business continuity in the face of natural disasters - (1) planning & coordination, (2) monitoring, (3) response/activation and (4) recovery.
Duvernoy, Claire S; Smith, Dean E; Manohar, Prerana; Schaefer, Ann; Kline-Rogers, Eva; Share, David; McNamara, Richard; Gurm, Hitinder S; Moscucci, Mauro
2010-04-01
Prior studies have shown a relationship between female gender and adverse outcomes after percutaneous coronary interventions (PCIs). Whether this relationship still exists with contemporary PCI remains to be determined. We evaluated gender differences in clinical outcomes in a large registry of contemporary PCI. Data were prospectively collected from 22,725 consecutive PCIs in a multicenter regional consortium (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) between January 2002 and December 2003. The primary end point was in-hospital all-cause mortality; other clinical outcomes evaluated included in-hospital death, vascular complications, transfusion, postprocedure myocardial infarction, stroke, and a combined major cardiovascular adverse event (MACE) end point including myocardial infarction, death, stroke, emergency coronary artery bypass grafting, and repeated PCI at the same site. Independent predictors of adverse outcomes were identified using multivariate logistic regression analysis. Compared with men, women were older, had a higher prevalence of comorbidities, and had a significantly higher frequency of adverse outcomes after PCI. After adjustment for baseline demographics, comorbidities, clinical presentation, and lesion characteristics, female gender was associated with an increased risk of in-hospital death, vascular complication, blood transfusion, stroke, and MACE. The relationship between female gender and increased risk of death and MACE was no longer present after further adjustment for kidney function and low body surface area. Differences in mortality rates between men and women no longer exist after PCI. However, our data suggest that technological advancements have not completely offset the relationship between gender and adverse outcomes after PCI. Copyright 2010 Mosby, Inc. All rights reserved.
Jackson, Elizabeth A; Munir, Khan; Schreiber, Theodore; Rubin, Jeffrey R; Cuff, Robert; Gallagher, Katherine A; Henke, Peter K; Gurm, Hitinder S; Grossman, P Michael
2014-06-17
This study sought to examine sex-related differences in outcomes related to peripheral vascular intervention (PVI) procedures. Percutaneous PVI is frequently performed for the treatment of peripheral arterial disease (PAD). However, little is known about sex-related differences related to PVI procedures. We assessed the impact of sex among 12,379 patients (41% female) who underwent lower extremity (LE)-PVI from 2004 to 2009 at 16 hospitals participating in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium PVI registry. Multivariate propensity-matched analyses were performed to adjust for differences in baseline characteristics, procedural indications, and comorbidities on the basis of sex. Compared with men, women were older and have multilevel disease and critical limb ischemia. In a propensity-matched analysis, female sex was associated with a higher rate of vascular complications, transfusions, and embolism. No differences were observed for in-hospital death, myocardial infarction, or stroke or transient ischemic attack. Technical success was more commonly achieved in women (91.2% vs. 89.1%, p = 0.014), but because of a higher complication rate, the overall procedural success rates were similar in men and women (79.7% vs. 81.6%, p = 0.08). Women represent a significant proportion of patients undergoing LE-PVI, have a more severe and complex disease process, and are at increased risk for adverse outcomes. Despite higher complications rates, women had similar procedural success compared with men, making PVI an effective treatment strategy among women with LE-PAD. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
The case for reassessment of health care technology. Once is not enough.
Banta, H D; Thacker, S B
1990-07-11
Assessment of health care technologies should be an iterative process, not a single event. In the United States there are an increasing number of organized attempts at reassessment of technologies by the health industry, professional societies, and national government agencies, such as the Medical Necessity Project of Blue Cross/Blue Shield, the Clinical Efficacy Assessment Project of the American College of Physicians, and the work of the US Preventive Services Task Force. We examine four clinical practices--electronic fetal monitoring, episiotomy, electroencephalography, and hysterectomy--to illustrate the need to continuously reassess existing technologies and to challenge our current inertia in this critical arena of health practice.
33 CFR 23.10 - Coast Guard emblem.
Code of Federal Regulations, 2010 CFR
2010-07-01
... ring all outlined in medium blue (Coast Guard blue), letters and numerals medium blue (Coast Guard blue), white area within ring, shield with medium blue (Coast Guard blue) chief and 13 alternating white and red (Coast Guard red) stripes (7 white and 6 red) with narrow medium blue (Coast Guard blue) outline...
33 CFR 23.10 - Coast Guard emblem.
Code of Federal Regulations, 2011 CFR
2011-07-01
... ring all outlined in medium blue (Coast Guard blue), letters and numerals medium blue (Coast Guard blue), white area within ring, shield with medium blue (Coast Guard blue) chief and 13 alternating white and red (Coast Guard red) stripes (7 white and 6 red) with narrow medium blue (Coast Guard blue) outline...
33 CFR 23.10 - Coast Guard emblem.
Code of Federal Regulations, 2013 CFR
2013-07-01
... ring all outlined in medium blue (Coast Guard blue), letters and numerals medium blue (Coast Guard blue), white area within ring, shield with medium blue (Coast Guard blue) chief and 13 alternating white and red (Coast Guard red) stripes (7 white and 6 red) with narrow medium blue (Coast Guard blue) outline...
33 CFR 23.10 - Coast Guard emblem.
Code of Federal Regulations, 2012 CFR
2012-07-01
... ring all outlined in medium blue (Coast Guard blue), letters and numerals medium blue (Coast Guard blue), white area within ring, shield with medium blue (Coast Guard blue) chief and 13 alternating white and red (Coast Guard red) stripes (7 white and 6 red) with narrow medium blue (Coast Guard blue) outline...
33 CFR 23.10 - Coast Guard emblem.
Code of Federal Regulations, 2014 CFR
2014-07-01
... ring all outlined in medium blue (Coast Guard blue), letters and numerals medium blue (Coast Guard blue), white area within ring, shield with medium blue (Coast Guard blue) chief and 13 alternating white and red (Coast Guard red) stripes (7 white and 6 red) with narrow medium blue (Coast Guard blue) outline...
Ho, Vivian; Metcalfe, Leanne; Dark, Cedric; Vu, Lan; Weber, Ellerie; Shelton, George; Underwood, Howard R
2017-12-01
We compare utilization, price per visit, and the types of care delivered across freestanding emergency departments (EDs), hospital-based EDs, and urgent care centers in Texas. We analyzed insurance claims processed by Blue Cross Blue Shield of Texas from 2012 to 2015 for patient visits to freestanding EDs, hospital-based EDs, or urgent care centers in 16 Texas metropolitan statistical areas containing 84.1% of the state's population. We calculated the aggregate number of visits, average price per visit, proportion of price attributable to facility and physician services, and proportion of price billed to Blue Cross Blue Shield of Texas versus out of pocket, by facility type. Prices for the top 20 diagnoses and procedures by facility type are compared. Texans use hospital-based EDs and urgent care centers much more than freestanding EDs, but freestanding ED utilization increased 236% between 2012 and 2015. The average price per visit was lower for freestanding EDs versus hospital-based EDs in 2012 ($1,431 versus $1,842), but prices in 2015 were comparable ($2,199 versus $2,259). Prices for urgent care centers were only $164 and $168 in 2012 and 2015. Out-of-pocket liability for consumers for all these facilities increased slightly from 2012 to 2015. There was 75% overlap in the 20 most common diagnoses at freestanding EDs versus urgent care centers and 60% overlap for hospital-based EDs and urgent care centers. However, prices for patients with the same diagnosis were on average almost 10 times higher at freestanding and hospital-based EDs relative to urgent care centers. Utilization of freestanding EDs is rapidly expanding in Texas. Higher prices at freestanding and hospital-based EDs relative to urgent care centers, despite substantial overlap in services delivered, imply potential inefficient use of emergency facilities. Copyright © 2017 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
From clinical integration to accountable care.
Shields, Mark
2011-01-01
Four key challenges to reforming health care organizations can be addressed by a clinical integration model patterned after Advocate Physician Partners (APP). These challenges are: predominance of small group practices, dominant fee-for-service reimbursement methods, weaknesses of the traditional hospital medical staff structure and a need to partner with commercial insurance companies. APP has demonstrated teamwork between 3800 physicians and hospitals to improve quality, patient safety and cost-effectiveness. Building on this model, an innovative contract with Blue Cross Blue Shield of Illinois serves as a prototype for a commercial Accountable Care Organization. For this contract to succeed, APP must outperform the market competition. To accomplish this, APP has implemented strategies to reduce readmissions, avoid unnecessary admissions and emergency room visits, expand primary care access, and enhance quality and patient safety.
The Common Law Power of the Legislature: Insurer Conversions and Charitable Funds
Horwitz, Jill R; Fremont-Smith, Marion R
2005-01-01
New York's Empire Blue Cross and Blue Shield conversion from nonprofit to for-profit form has considerable legal significance. Three aspects of the conversion make the case unique: the role of the state legislature in directing the disposition of the conversion assets, the fact that it made itself the primary beneficiary of those assets, and the actions of the state attorney general defending the state rather than the public interest in the charitable assets. Drawing on several centuries of common law rejecting the legislative power to direct the disposition of charitable funds, this article argues that the legislature lacked power to control the conversion and direct the disposition of its proceeds and that its actions not only undermined the nonprofit form but also raised constitutional concerns. PMID:15960770
NASA Astrophysics Data System (ADS)
Wainscoat, Richard
2015-08-01
Across the planet, conventional light sources such as high pressure sodium, are rapidly being replaced by light emitting diodes (LEDs). As light fixtures are being replaced, there is a tremendous opportunity for restoration of dark night skies through replacement of poorly shielded fixtures by fully shielded fixtures. However, it is critically important to limit the amount of blue light from the LEDs.Sales people are strongly promoting LEDs with high correlated color temperature (CCT), such as 5000K. They are promoting them on energy efficiency grounds - higher energy efficiency is easier to sell. These LEDs have tremendous amounts of blue light near 450 nm. The photopic human eye is relatively insensitive to this blue light, but the dark adapted scotopic eye is much more sensitive, and CCDs are also very sensitive to this wavelength of light. As a consequence, both professional and amateur astronomers are very seriously impacted by high CCT LED lighting. The sodium lighting that the LEDs are replacing has relatively little blue light. Blue light is strongly scattered by air molecules in the atmosphere.Use of high CCT LED lighting will cause further deterioration of night sky quality.In contrast, use of LED lighting with low CCT (e.g., 2400K or 2700K), or use of filters to remove the blue light, can restore the dark night sky. LED lighting is much easier to direct, meaning that an area such as a roadway can be lit with many less lumens with LEDs compared to conventional lights such as high pressure sodium. And use of fully shielded fixtures will eliminate direct uplighting.It is therefore critically important at this time to require that all new LED lighting be fully shielded, and for strong limits to be placed the amount of blue light from LEDs. This is crucial near observatories, but is important everywhere.
Airborne Data Link Operational Evaluation Test Plan
1993-08-01
be provided by a combination of glare shield mounted, blue lens , aviation-type lamps and lighted distinctive message indicators on the CDUs or CDU...consist of either SELCAL sound only or SELCAL tone combined with forward primary field of view visual alerting (a blue light mounted on the glare shield in...INCORPORATED DOT/FAA/CT-TN93/30 9. Pe’form,"g Orgaoniatio Name end Address 10. Work Unit No. (TRAIS) CTA, INCORPORATED Suite 1000 11 Contac of Great me. 2500
Winning against big tobacco. Let's take the time to get it right.
Humphrey, H H
1997-01-01
Three years ago, the state of Minnesota became the second state to sue the tobacco industry for wrongdoing and the first to charge consumer fraud and conspiracy. Together with our co-plaintiff, Blue Cross/Blue Shield of Minnesota, we filed a lawsuit against the six major U.S. cigarette manufacturers, two tobacco trade organizations, and British American Tobacco Industries (BAT), the parent company of Brown and Williamson. Specifically, the lawsuit alleges that the industry defrauded consumers and engaged in false advertising, deceptive practices, and anti-trust violations, including conspiracy to stifle development of safer cigarettes and to conceal information on smoking and health. Many later-filing states patterned complaints after Minnesota's, and virtually all have incorporated some or all of the claims first pled in the Minnesota complaint. Images p379-a p384-a PMID:9323388
Ridgely, M Susan; Burnam, M Audrey; Barry, Colleen L; Goldman, Howard H; Hennessy, Kevin D
2006-01-01
The government often uses the Federal Employees Health Benefits (FEHB) Program as a model for both public and private health policy choices. In 2001, the U.S. Office of Personnel Management (OPM) implemented full parity, requiring that FEHB carriers offer mental health and substance abuse benefits equal to general medical benefits. OPM instructed carriers to alter their benefit design but permitted them to determine whether they would manage care and what structures or processes they would use. This article reports on the experience of 156 carriers and the government-wide BlueCross and BlueShield Service Benefit Plan. Carriers dropped cost-restraining benefit limits. A smaller percentage also changed the management of the benefit, but these changes affected the care of many enrollees, making the overall parity effect noteworthy. PMID:16529573
Ridgely, M Susan; Burnam, M Audrey; Barry, Colleen L; Goldman, Howard H; Hennessy, Kevin D
2006-01-01
The government often uses the Federal Employees Health Benefits (FEHB) Program as a model for both public and private health policy choices. In 2001, the U.S. Office of Personnel Management (OPM) implemented full parity, requiring that FEHB carriers offer mental health and substance abuse benefits equal to general medical benefits. OPM instructed carriers to alter their benefit design but permitted them to determine whether they would manage care and what structures or processes they would use. This article reports on the experience of 156 carriers and the government-wide BlueCross and BlueShield Service Benefit Plan. Carriers dropped cost-restraining benefit limits. A smaller percentage also changed the management of the benefit, but these changes affected the care of many enrollees, making the overall parity effect noteworthy.
Code of Federal Regulations, 2011 CFR
2011-10-01
... blue, all within an encircling inscription “National Transportation Safety Board.” When illustrated in... the eagle's beak. The arrows and the olive branch are a lighter shade of gold. The red and blue of the shield are national flag red and blue. The official seal of the Board, in black and white, appears below...
Code of Federal Regulations, 2013 CFR
2013-10-01
... blue, all within an encircling inscription “National Transportation Safety Board.” When illustrated in... the eagle's beak. The arrows and the olive branch are a lighter shade of gold. The red and blue of the shield are national flag red and blue. The official seal of the Board, in black and white, appears below...
Code of Federal Regulations, 2014 CFR
2014-10-01
... blue, all within an encircling inscription “National Transportation Safety Board.” When illustrated in... the eagle's beak. The arrows and the olive branch are a lighter shade of gold. The red and blue of the shield are national flag red and blue. The official seal of the Board, in black and white, appears below...
Code of Federal Regulations, 2012 CFR
2012-10-01
... blue, all within an encircling inscription “National Transportation Safety Board.” When illustrated in... the eagle's beak. The arrows and the olive branch are a lighter shade of gold. The red and blue of the shield are national flag red and blue. The official seal of the Board, in black and white, appears below...
Code of Federal Regulations, 2010 CFR
2010-10-01
... blue, all within an encircling inscription “National Transportation Safety Board.” When illustrated in... the eagle's beak. The arrows and the olive branch are a lighter shade of gold. The red and blue of the shield are national flag red and blue. The official seal of the Board, in black and white, appears below...
The Alternative Quality Contract: Impact on Service Use and Spending for Children With ADHD.
Joyce, Nina R; Huskamp, Haiden A; Hadland, Scott E; Donohue, Julie M; Greenfield, Shelly F; Stuart, Elizabeth A; Barry, Colleen L
2017-12-01
In 2009, Blue Cross-Blue Shield of Massachusetts (BCBSMA) implemented the alternative quality contract (AQC), which pays provider organizations a global payment for all services used by enrollees. BCBSMA claims for 2006-2011 were used to compare youths enrolled in provider organizations participating in the AQC (7,407 person-years [PYs]) with those not participating (45,398 PYs). Difference-in-differences models estimated changes in mental health and substance abuse treatment service utilization and spending attributable to the AQC. The AQC was associated with small increases in the probability of any outpatient visits and in the probability and number of medication management visits among children with attention-deficit hyperactivity disorder (ADHD). Spending did not change, and there was no evidence of reductions in service utilization or spending for children with ADHD in the first three years of AQC implementation.
Marshfield Clinic, physician networks, and the exercise of monopoly power.
Greenberg, W
1998-01-01
OBJECTIVE: Antitrust enforcement can improve the performance of large, vertically integrated physician-hospital organizations (PHOs). Objective: To examine the recent court decisions in the Blue Cross and Blue Shield United of Wisconsin v. Marshfield Clinic antitrust case to understand better the benefits and costs of vertical integration in healthcare. SUMMARY AND CONCLUSIONS: Vertical integration in the Marshfield Clinic may have had the benefits of reducing transactions and uncertainty costs while improving the coordination between ambulatory and inpatient visits, but at the cost of Marshfield Clinic's monopolizing of physician services and foreclosing of HMO entry in northwest Wisconsin. The denial of hospital staff privileges to non-Marshfield Clinic physicians combined with certificate-of-need regulations impeded physician entry and solidified Marshfield Clinic's monopoly position. Enforcement efforts of recent antitrust guidelines by the U.S. Department of Justice and the Federal Trade Commission will need to address carefully the benefits and costs of vertically integrated systems. PMID:9865229
10 CFR 1.51 - Description and custody of NRC seal.
Code of Federal Regulations, 2014 CFR
2014-01-01
...) of brown and tan with claws and beak of yellow, behind a shield of red, white, and blue, clutching a... field of white, with the words “United States Nuclear Regulatory Commission” in dark blue encircling the...
10 CFR 1.51 - Description and custody of NRC seal.
Code of Federal Regulations, 2012 CFR
2012-01-01
...) of brown and tan with claws and beak of yellow, behind a shield of red, white, and blue, clutching a... field of white, with the words “United States Nuclear Regulatory Commission” in dark blue encircling the...
Opportunities and Challenges for Payment Reform: Observations from Massachusetts.
Mechanic, Robert E
2016-08-01
Policy makers and private health plans are expanding their efforts to implement new payment models that will encourage providers to improve quality and deliver health care more efficiently. Over the past five years, payment reforms have progressed faster in Massachusetts than in any other state. The reasons include a major effort by Blue Cross Blue Shield of Massachusetts to implement global payment, the presence of large integrated systems willing to take on financial risk, and a supportive state policy environment. By 2014, thirty-seven percent of Massachusetts's residents enrolled in health plans were covered under risk-based payment models tied to global budgets. But the expansion of payment reform in Massachusetts slowed between 2012 and 2015 because some commercial enrollment shifted from risk-based health maintenance organization products to fee-for-service preferred provider organization (PPO) plans, and the state Medicaid program fell short of its payment reform goals. Provider groups will not fully commit to population-based clinical models if they believe it will result in large reductions in fee-for-service revenue. The use of alternative payment models will accelerate in 2016 when Blue Cross begins implementing PPO payment reforms, but it is unknown how quickly other payers will follow. Massachusetts's experience illustrates the complexity of payment reform in pluralistic health care markets and the need for complementary efforts by public and private stakeholders. Copyright © 2016 by Duke University Press.
Forgione, D A
1999-01-01
With the ever-increasing market penetration of capitated payment systems throughout health care markets, average payment rates for health services have dropped correspondingly. At the same time, the added competitive pressures from managed care organizations have served to increase the demand for new capital investment in information systems, lower cost facilities, and innovative modes for delivering all types of health care services. As a result, many nonprofit health care organizations have converted, or have attempted to convert, to for-profit status in an effort to gain access to the public equity capital markets. As hospitals, Blue Cross and Blue Shield organizations, and other nonprofit health care organizations across the U.S. seek to convert to for-profit status, they are finding the path is not easy. Access to capital, operating efficiencies, and the need to accelerate movement into new markets are offset by public benefit obligations, potential private inurement, and significant political cost issues. The bottom line is whether the conversion will be structured to both protect the public interest and allow the health care organization the flexibility and access to capital it needs in order to continue as a viable, competitive organization into the next millennium.
New Hampshire Nurse Practitioners Take the Lead in Forming an Accountable Care Organization.
Wright, Wendy L
In 2012, New Hampshire nurse practitioners (NPs), along with Anthem Blue Cross/Blue Shield, formed the first Patient Centered Shared Savings Program in the nation, composed of patients managed by nurse practitioners employed within NP-owned and operated clinics. In this accountable care organization (ACO), NP-attributed patients were grouped into one risk pool. Data from the ACO and the NP risk pool, now in its third year, have produced compelling statistics. Nurse practitioners participating in this program have met or exceeded the minimum scores for 29 quality metrics along with a demonstrated cost-savings in the first 2 years of the program. Hospitalization rates for NP-managed patients are among the lowest in the state. Cost of care for NP-managed patients is $66.85 less per member per month than the participating physician-managed patients. Data from this ACO provide evidence that NPs provide cost-effective, quality health care and are integral to the formation and sustainability of any ACO.
Frey, Allison; Mika, Stephanie; Nuzum, Rachel; Schoen, Cathy
2009-06-01
Many proposed health insurance reforms would establish a federal minimum benefit standard--a baseline set of benefits to ensure that people have adequate coverage and financial protection when they purchase insurance. Currently, benefit mandates are set at the state level; these vary greatly across states and generally target specific areas rather than set an overall standard for what qualifies as health insurance. This issue brief considers what a broad federal minimum standard might look like by comparing existing state benefit mandates with the services and providers covered under the Federal Employees Health Benefits Program (FEHBP) Blue Cross and Blue Shield standard benefit package, an example of minimum creditable coverage that reflects current standard practice among employer-sponsored health plans. With few exceptions, benefits in the FEHBP standard option either meet or exceed those that state mandates require-indicating that a broad-based national benefit standard would include most existing state benefit mandates.
Use of Diagnosis-Related Groups by Non-Medicare Payers
Carter, Grace M.; Jacobson, Peter D.; Kominski, Gerald F.; Perry, Mark J.
1994-01-01
Medicare's prospective payment system (PPS) for hospital cases is based on diagnosis-related groups (DRGs). A wide variety of other third-party payers for hospital care have adapted elements of this system for their own use. The extent of DRG use varies considerably both by type of payer and by geographical area. Users include: 21 State Medicaid programs, 3 workers' compensation systems, the Civilian Health and Medical Program of the Uniformed Services (CHAMPUS), more than one-half of the Blue Cross and Blue Shield Association (BCBSA) member plans, several self-insured employers, and a few employer coalitions. We describe how each of these payers use DRGs. No single approach is dominant. Some payers negotiate specific prices for so many combinations of DRG and hospital that the paradigm that payment equals rate times weight does not apply. What has emerged appears to be a very flexible payment system in which the only constant is the use of DRGs as a measure of output. PMID:10142368
Utilization of medical care following the Three Mile Island crisis.
Houts, P S; Hu, T W; Henderson, R A; Cleary, P D; Tokuhata, G
1984-02-01
Four studies are reported on how utilization of primary health care was affected by the Three Mile Island (TMI) crisis and subsequent distress experienced by persons living in the vicinity of the plant. The studies concerned: 1) Blue Cross-Blue Shield records of claims by primary care physicians in the vicinity of TMI; 2) utilization rates in a family practice located near the facility; 3) interviews with persons living within five miles of TMI following the crisis; and 4) responses to a questionnaire by primary care physicians practicing within 25 miles of TMI. All four studies indicated only slight increases in utilization rates during the year following the crisis. One study found that persons who were upset during the crisis tended to be high practice utilizers both before and after the crisis. These results suggest that, while patterns of physician utilization prior to the TMI crisis predicted emotional response during the crisis, the impact of the TMI crisis on subsequent physician utilization was small.
Utilization of medical care following the Three Mile Island crisis.
Houts, P S; Hu, T W; Henderson, R A; Cleary, P D; Tokuhata, G
1984-01-01
Four studies are reported on how utilization of primary health care was affected by the Three Mile Island (TMI) crisis and subsequent distress experienced by persons living in the vicinity of the plant. The studies concerned: 1) Blue Cross-Blue Shield records of claims by primary care physicians in the vicinity of TMI; 2) utilization rates in a family practice located near the facility; 3) interviews with persons living within five miles of TMI following the crisis; and 4) responses to a questionnaire by primary care physicians practicing within 25 miles of TMI. All four studies indicated only slight increases in utilization rates during the year following the crisis. One study found that persons who were upset during the crisis tended to be high practice utilizers both before and after the crisis. These results suggest that, while patterns of physician utilization prior to the TMI crisis predicted emotional response during the crisis, the impact of the TMI crisis on subsequent physician utilization was small. PMID:6691524
Cross Section Sensitivity and Propagated Errors in HZE Exposures
NASA Technical Reports Server (NTRS)
Heinbockel, John H.; Wilson, John W.; Blatnig, Steve R.; Qualls, Garry D.; Badavi, Francis F.; Cucinotta, Francis A.
2005-01-01
It has long been recognized that galactic cosmic rays are of such high energy that they tend to pass through available shielding materials resulting in exposure of astronauts and equipment within space vehicles and habitats. Any protection provided by shielding materials result not so much from stopping such particles but by changing their physical character in interaction with shielding material nuclei forming, hopefully, less dangerous species. Clearly, the fidelity of the nuclear cross-sections is essential to correct specification of shield design and sensitivity to cross-section error is important in guiding experimental validation of cross-section models and database. We examine the Boltzmann transport equation which is used to calculate dose equivalent during solar minimum, with units (cSv/yr), associated with various depths of shielding materials. The dose equivalent is a weighted sum of contributions from neutrons, protons, light ions, medium ions and heavy ions. We investigate the sensitivity of dose equivalent calculations due to errors in nuclear fragmentation cross-sections. We do this error analysis for all possible projectile-fragment combinations (14,365 such combinations) to estimate the sensitivity of the shielding calculations to errors in the nuclear fragmentation cross-sections. Numerical differentiation with respect to the cross-sections will be evaluated in a broad class of materials including polyethylene, aluminum and copper. We will identify the most important cross-sections for further experimental study and evaluate their impact on propagated errors in shielding estimates.
NASA Astrophysics Data System (ADS)
Vigneron, Jean Pol; Ouedraogo, Moussa; Colomer, Jean-François; Rassart, Marie
2009-02-01
The African shield-backed bug Calidea panaethiopica is a very colorful insect which produces a range of iridescent yellow, green, and blue reflections. The cuticle of the dorsal side of the insect, on the shield, the prothorax and part of the head, is pricked of uniformly distributed hemispherical hollow cavities a few tens micrometers deep. Under normal illumination and viewing the insect’s muffin-tin shaped surface gives rise to two distinct colors: a yellow spot arising from the bottom of the well and a blue annular cloud that appears to float around the yellow spot. This effect is explained by multiple reflections on a hemispherical Bragg mirror with a mesoscopic curvature. A multiscale computing methodology was found to be needed to evaluate the reflection spectrum for such a curved multilayer. This multiscale approach is very general and should be useful for dealing with visual effects in many natural and artificial systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hong, Woo-Pyo; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 426-791
2015-01-15
The influence of quantum diffraction and shielding on the electron-ion collision process is investigated in two-component semiclassical plasmas. The eikonal method and micropotential taking into account the quantum diffraction and shielding are used to obtain the eikonal scattering phase shift and the eikonal collision cross section as functions of the collision energy, density parameter, Debye length, electron de Broglie wavelength, and the impact parameter. The result shows that the quantum diffraction and shielding effects suppress the eikonal scattering phase shift as well as the differential eikonal collision cross section, especially, in small-impact parameter regions. It is also shown that themore » quantum shielding effect on the eikonal collision cross section is more important in low-collision energies. In addition, it is found that the eikonal collision cross section increases with an increase in the density parameter. The variations of the eikonal cross section due to the quantum diffraction and shielding effects are also discussed.« less
The impact of an online disease management program on medical costs among health plan members.
Schwartz, Steven M; Day, Brian; Wildenhaus, Kevin; Silberman, Anna; Wang, Chun; Silberman, Jordan
2010-01-01
This study evaluated the economic impact of an online disease management program within a broader population health management strategy. A retrospective, quasi-experimental, cohort design evaluated program participants and a matched cohort of nonparticipants on 2003-2007 claims data in a mixed model. The study was conducted through Highmark Inc, Blue Cross Blue Shield, covering 4.8 million members in five regions of Pennsylvania. Overall, 413 online self-management program participants were compared with a matched cohort of 360 nonparticipants. The costs and claims data were measured per person per calendar year. Total payments were aggregated from inpatient, outpatient, professional services, and pharmacy payments. The costs of the online program were estimated on a per-participant basis. All dollars were adjusted to 2008 values. The online intervention, implemented in 2006, was a commercially available, tailored program for chronic condition self management, nested within the Blues on Call(SM) condition management strategy. General linear modeling (with covariate adjustment) was used. Data trends were also explored using second-order polynomial regressions. Health care costs per person per year were $757 less than predicted for participants relative to matched nonparticipants, yielding a return on investment of $9.89 for every dollar spent on the program. This online intervention showed a favorable and cost-effective impact on health care cost.
Ross, Kaile M; Klein, Betsy; Ferro, Katherine; McQueeney, Debra A; Gernon, Rebecca; Miller, Benjamin F
2018-04-30
This project evaluated the cost effectiveness of integrating behavioral health services into a primary care practice using a prospective, case-control design. New Directions Behavioral Health collaborated with a large Kansas City primary care practice to integrate a licensed psychologist (i.e., behavioral health clinician) into the practice. Patient claims data were examined 21 months prior to and 14 months after the psychologist began providing full-time behavioral health services within the practice. Claims data from patients with Blue Cross Blue Shield of Kansas City insurance (BCBSKC) who had at least one encounter with the psychologist (N = 239) were compared to control patients (BCBSKC fully insured patients at large) to calculate cost savings. The results demonstrated that integrating behavioral health services into the practice was associated with $860.16 per member per year savings or 10.8% savings in costs for BCBSKC patients. Integrating behavioral health services into primary care may lead to reductions in health care costs.
The Economic Impact of Exposure to Secondhand Smoke in Minnesota
Foldes, Steven S.; Alesci, Nina L.; Samet, Jonathan
2009-01-01
Objectives. Using the risk categories established by the 2006 US surgeon general's report, we estimated medical treatment costs related to exposure to secondhand tobacco smoke (SHS) in the state of Minnesota. Methods. We estimated the prevalence and costs of treated medical conditions related to SHS exposure in 2003 with data from Blue Cross and Blue Shield (Minnesota's largest insurer), the Current Population Survey, and population attributable risk estimates for these conditions reported in the scientific literature. We adjusted treatment costs to the state level by health insurance category by using the Medical Expenditure Panel Survey. Results. The total annual cost of treatment in Minnesota for conditions for which the 2006 surgeon general's report found sufficient evidence to conclude a causal link with exposure to SHS was $228.7 million in 2008 dollars—equivalent to $44.58 per Minnesota resident. Sensitivity analyses showed a range from $152.1 million to $330.0 million. Conclusions. The results present a strong rationale for regulating smoking in public places and were used to support the passage of Minnesota's Freedom to Breathe Act of 2007. PMID:19197082
Markovitz, Amanda R; Alexander, Jeffrey A; Lantz, Paula M; Paustian, Michael L
2015-04-01
The patient-centered medical home (PCMH) model of primary care is being implemented in a wide variety of socioeconomic contexts, yet there has been little research on whether its effects differ by context. Clinical preventive service use, including cancer screening, is an important outcome to assess the effectiveness of the PCMH within and across socioeconomic contexts. To determine whether the relationship between the PCMH and cancer screening is conditional on the socioeconomic context in which a primary care physician practice operates. A longitudinal study spanning July 1, 2009, through June 30, 2012, using data from the Blue Cross Blue Shield of Michigan Physician Group Incentive Program was conducted. Michigan nonpediatric primary care physician practices that participated in the Physician Group Incentive Program (5452 practice-years) were included. Sample size and outlier exclusion criteria were applied to each outcome. We examined the interaction between practices' PCMH implementation scores and their socioeconomic context. The implementation of a PCMH was self-reported by the practice's affiliated physician organizations and was measured as a continuous score ranging from 0 to 1. Socioeconomic context was calculated using a market-based approach based on zip code characteristics of the practice's patients and by combining multiple measures using principal components analysis. Breast, cervical, and colorectal cancer screening rates for practices' Blue Cross Blue Shield of Michigan patients. The implementation of a PCMH was associated with higher breast, cervical, and colorectal cancer screening rates across most market socioeconomic contexts. In multivariable models, the PCMH was associated with a higher rate of screening for breast cancer (5.4%; 95% CI, 1.5% to 9.3%), cervical cancer (4.2%; 95% CI, 1.4% to 6.9%), and colorectal cancer (7.0%; 95% CI, 3.6% to 10.5%) in the lowest socioeconomic group but nonsignificant differences in screening for breast cancer (2.6%; 95% CI, -0.1% to 5.3%) and cervical cancer (-0.5%; 95% CI, -2.7% to 1.7%) and a higher rate of colorectal cancer (4.5%; 95% CI, 1.8% to 7.3%) screening in the highest socioeconomic group. Because PCMH implementation was associated with larger increases in screening in lower socioeconomic practice settings, models suggest reduced disparities in screening rates across these contexts. For example, the model-predicted disparity in breast cancer screening rates between the highest and lowest socioeconomic contexts was 6% (77.9% vs 72.2%) among practices with no PCMH implementation and 3% (80.3% vs. 77.0%) among practices with full PCMH implementation. In our study, the PCMH model was associated with improved cancer screening rates across contexts but may be especially relevant for practices in lower socioeconomic areas.
NASA-Lewis experiences with multigroup cross sections and shielding calculations
NASA Technical Reports Server (NTRS)
Lahti, G. P.
1972-01-01
The nuclear reactor shield analysis procedures employed at NASA-Lewis are described. Emphasis is placed on the generation, use, and testing of multigroup cross section data. Although coupled neutron and gamma ray cross section sets are useful in two dimensional Sn transport calculations, much insight has been gained from examination of uncoupled calculations. These have led to experimental and analytic studies of areas deemed to be of first order importance to reactor shield calculations. A discussion is given of problems encountered in using multigroup cross sections in the resolved resonance energy range. The addition to ENDF files of calculated and/or measured neutron-energy-dependent capture gamma ray spectra for shielding calculations is questioned for the resonance region. Anomalies inherent in two dimensional Sn transport calculations which may overwhelm any cross section discrepancies are illustrated.
Assessment of the MPACT Resonance Data Generation Procedure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Kang Seog; Williams, Mark L.
Currently, heterogeneous models are being used to generate resonance self-shielded cross-section tables as a function of background cross sections for important nuclides such as 235U and 238U by performing the CENTRM (Continuous Energy Transport Model) slowing down calculation with the MOC (Method of Characteristics) spatial discretization and ESSM (Embedded Self-Shielding Method) calculations to obtain background cross sections. And then the resonance self-shielded cross section tables are converted into subgroup data which are to be used in estimating problem-dependent self-shielded cross sections in MPACT (Michigan Parallel Characteristics Transport Code). Although this procedure has been developed and thus resonance data have beenmore » generated and validated by benchmark calculations, assessment has never been performed to review if the resonance data are properly generated by the procedure and utilized in MPACT. This study focuses on assessing the procedure and a proper use in MPACT.« less
NASA Astrophysics Data System (ADS)
Lee, Myoung-Jae; Jung, Young-Dae
2017-10-01
The influence of quantum shielding on the Ramsauer-Townsend phenomena for the total electron-atom polarisation collision cross-section is investigated in partially ionised strongly coupled semiclassic plasmas. The result shows that the quantum shielding effect changes the position of the Ramsauer energy in partially ionised strongly coupled plasmas. It is also found that the quantum shielding effect enhances the total electron-atom collision cross-section when the collision energy is greater than the Ramsauer energy; however, it suppresses the collision cross-section when the collision energy is smaller than the Ramsauer energy. In addition, it is shown that the plasma screening effect significantly changes the position of the Ramsauer energy and the influence of plasma screening on the magnitude of the collision cross-section is more significant near the Ramsauer energy domain. The variations of the Ramsauer energy and the collision cross-section due to the quantum shielding effect are also discussed.
Performance study of galactic cosmic ray shield materials
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Wilson, John W.; Thibeault, Sheila A.; Nealy, John E.; Badavi, Francis F.; Kiefer, Richard L.
1994-01-01
The space program is faced with two difficult radiation protection issues for future long-term operations. First, retrofit of shield material or conservatism in shield design is prohibitively expensive and often impossible. Second, shielding from the cosmic heavy ions is faced with limited knowledge on the physical properties and biological responses of these radiations. The current status of space shielding technology and its impact on radiation health is discussed herein in terms of conventional protection practice and a test biological response model. The impact of biological response on the selection of optimum materials for cosmic ray shielding is presented in terms of the transmission characteristics of the shield material. Although the systematics of nuclear cross sections are able to demonstrate the relation of exposure risk to shield-material composition, the current uncertainty in-nuclear cross sections will not allow an accurate evaluation of risk reduction. This paper presents a theoretical study of risk-related factors and a pilot experiment to study the effectiveness of choice of shield materials to reduce the risk in space operations.
39 CFR 3002.3 - Official seal.
Code of Federal Regulations, 2012 CFR
2012-07-01
... inscribed at top POSTAL RATE COMMISSION and in base, between two small five-pointed stars, 1970, all in gold, the shield of the coat of arms in full color blazoned as follows: Five blue stars on a white stripe...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-14
........ November 23, 2009. Blue Shield, Senior Medicare, Claims Rep Unit, Kelly Services. 74,934 Ilpea Industries... terminating investigations were issued because the petitioning groups of workers are covered by active...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, Mi-Young; Yoon, Jung-Sik; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr
2015-04-15
The renormalization shielding effects on the electron-impact ionization of hydrogen atom are investigated in dense partially ionized plasmas. The effective projectile-target interaction Hamiltonian and the semiclassical trajectory method are employed to obtain the transition amplitude as well as the ionization probability as functions of the impact parameter, the collision energy, and the renormalization parameter. It is found that the renormalization shielding effect suppresses the transition amplitude for the electron-impact ionization process in dense partially ionized plasmas. It is also found that the renormalization effect suppresses the differential ionization cross section in the peak impact parameter region. In addition, it ismore » found that the influence of renormalization shielding on the ionization cross section decreases with an increase of the relative collision energy. The variations of the renormalization shielding effects on the electron-impact ionization cross section are also discussed.« less
Estes, Chris; Lee, Christopher
2009-01-01
Objectives. We quantified the economic cost of selected environmental factors among North Carolina children living in substandard housing. Methods. We gathered data on direct medical care costs for specific childhood medical conditions associated with environmental factors commonly found in substandard housing. Medical claims data for 2006 and 2007 were obtained from BlueCross BlueShield of North Carolina and the North Carolina Department of Health and Human Services. Indirect costs were based in part on nonmedical data obtained from several previous studies. Results. Total (direct and indirect) costs for the conditions assessed exceeded $92 million in 2006 and $108 million in 2007. Neurobehavioral conditions contributed to more than 52% of all costs, followed by lead poisoning (20%) and respiratory conditions (12%). Neurobehavioral conditions were the largest contributor to direct medical costs (44%), followed by respiratory conditions (38%) and accidental burns and falls (10%). Conclusions. Direct and indirect costs associated with environmental factors appear to be increasing at about twice the rate of medical inflation. More aggressive policies and funding are needed to reduce the substantial financial impact of childhood illnesses associated with substandard housing in North Carolina. PMID:19890173
Early Impact Of CareFirst's Patient-Centered Medical Home With Strong Financial Incentives.
Afendulis, Christopher C; Hatfield, Laura A; Landon, Bruce E; Gruber, Jonathan; Landrum, Mary Beth; Mechanic, Robert E; Zinner, Darren E; Chernew, Michael E
2017-03-01
In 2011 CareFirst BlueCross BlueShield, a large mid-Atlantic health insurance plan, implemented a payment and delivery system reform program. The model, called the Total Care and Cost Improvement Program, includes enhanced payments for primary care, significant financial incentives for primary care physicians to control spending, and care coordination tools to support progress toward the goal of higher-quality and lower-cost patient care. We conducted a mixed-methods evaluation of the initiative's first three years. Our quantitative analyses used spending and utilization data for 2010-13 to compare enrollees who received care from participating physician groups to similar enrollees cared for by nonparticipating groups. Savings were small and fully shared with providers, which suggests no significant effect on total spending (including bonuses). Our qualitative analysis suggested that early in the program, many physicians were not fully engaged with the initiative and did not make full use of its tools. These findings imply that this and similar payment reforms may require greater time to realize significant savings than many stakeholders had expected. Patience may be necessary if payer-led reform is going to lead to system transformation. Project HOPE—The People-to-People Health Foundation, Inc.
McBride, Timothy D; Barker, Abigail R; Pollack, Lisa M; Kemper, Leah M; Mueller, Keith J
2012-06-01
The Affordable Care Act calls for creation of health insurance exchanges designed to provide private health insurance plan choices. The Federal Employees Health Benefits Program is a national model that to some extent resembles the planned exchanges. Both offer plans at the state level but are also overseen by the federal government. We examined the availability of plans and enrollment levels in the Federal Employees Health Benefits Program throughout the United States in 2010. We found that although plans were widely available, enrollment was concentrated in plans owned by just a few organizations, typically Blue Cross/Blue Shield plans. Enrollment was more concentrated in rural areas, which may reflect historical patterns of enrollment or lack of provider networks. Average biweekly premiums for an individual were lowest ($58.48) in counties where competition was extremely high, rising to $65.13 where competition was extremely low. To make certain that coverage sold through exchanges is affordable, policy makers may need to pay attention to areas where there is little plan competition and take steps through risk-adjustment policies or other measures to narrow differences in premiums and out-of-pocket expenses for consumers.
Lemak, Christy Harris; Nahra, Tammie A; Cohen, Genna R; Erb, Natalie D; Paustian, Michael L; Share, David; Hirth, Richard A
2015-04-01
As policy makers and others seek to reduce health care cost growth while improving health care quality, one approach gaining momentum is fee-for-value reimbursement. This payment strategy maintains the traditional fee-for-service arrangement but includes quality and spending incentives. We examined Blue Cross Blue Shield of Michigan's Physician Group Incentive Program, which uses a fee-for-value approach focused on primary care physicians. We analyzed the program's impact on quality and spending from 2008 to 2011 for over three million beneficiaries in over 11,000 physician practices. Participation in the incentive program was associated with approximately 1.1 percent lower total spending for adults (5.1 percent lower for children) and the same or improved performance on eleven of fourteen quality measures over time. Our findings contribute to the growing body of evidence about the potential effectiveness of models that align payment with cost and quality performance, and they demonstrate that it is possible to transform reimbursement within a fee-for-service framework to encourage and incentivize physicians to provide high-quality care, while also reducing costs. Project HOPE—The People-to-People Health Foundation, Inc.
Barry, Colleen L.; Stuart, Elizabeth A.; Donohue, Julie M.; Greenfield, Shelly F.; Kouri, Elena; Duckworth, Kenneth; Song, Zirui; Mechanic, Robert E.; Chernew, Michael E.; Huskamp, Haiden A.
2016-01-01
Accountable care using global payment with performance bonuses has shown promise in controlling spending growth and improving care. This study examined how an early model, the Alternative Quality Contract (AQC) established in 2009 by Blue Cross Blue Shield of Massachusetts (BCBSMA), has affected care for mental illness. We compared spending and use for enrollees in AQC organizations that did and did not accept financial risk for mental health with enrollees not participating in the contract. Compared with BCBSMA enrollees in organizations not participating in the AQC, we found that enrollees in organizations participating in the AQC were slightly less likely to use mental health services and had small declines in total health care spending, but no change was found in mental health spending among all users. The declines in probability of use of mental health services and in total health spending attributable to the AQC were concentrated among enrollees in AQC organizations that accepted financial risk for behavioral health. Interviews with AQC organization leaders suggested that the contractual arrangements did not meaningfully affect mental health care delivery in the program’s initial years, but organizations are now at varying stages of efforts to improve integration. PMID:26643628
Predicting complications of percutaneous coronary intervention using a novel support vector method.
Lee, Gyemin; Gurm, Hitinder S; Syed, Zeeshan
2013-01-01
To explore the feasibility of a novel approach using an augmented one-class learning algorithm to model in-laboratory complications of percutaneous coronary intervention (PCI). Data from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) multicenter registry for the years 2007 and 2008 (n=41 016) were used to train models to predict 13 different in-laboratory PCI complications using a novel one-plus-class support vector machine (OP-SVM) algorithm. The performance of these models in terms of discrimination and calibration was compared to the performance of models trained using the following classification algorithms on BMC2 data from 2009 (n=20 289): logistic regression (LR), one-class support vector machine classification (OC-SVM), and two-class support vector machine classification (TC-SVM). For the OP-SVM and TC-SVM approaches, variants of the algorithms with cost-sensitive weighting were also considered. The OP-SVM algorithm and its cost-sensitive variant achieved the highest area under the receiver operating characteristic curve for the majority of the PCI complications studied (eight cases). Similar improvements were observed for the Hosmer-Lemeshow χ(2) value (seven cases) and the mean cross-entropy error (eight cases). The OP-SVM algorithm based on an augmented one-class learning problem improved discrimination and calibration across different PCI complications relative to LR and traditional support vector machine classification. Such an approach may have value in a broader range of clinical domains.
Predicting complications of percutaneous coronary intervention using a novel support vector method
Lee, Gyemin; Gurm, Hitinder S; Syed, Zeeshan
2013-01-01
Objective To explore the feasibility of a novel approach using an augmented one-class learning algorithm to model in-laboratory complications of percutaneous coronary intervention (PCI). Materials and methods Data from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) multicenter registry for the years 2007 and 2008 (n=41 016) were used to train models to predict 13 different in-laboratory PCI complications using a novel one-plus-class support vector machine (OP-SVM) algorithm. The performance of these models in terms of discrimination and calibration was compared to the performance of models trained using the following classification algorithms on BMC2 data from 2009 (n=20 289): logistic regression (LR), one-class support vector machine classification (OC-SVM), and two-class support vector machine classification (TC-SVM). For the OP-SVM and TC-SVM approaches, variants of the algorithms with cost-sensitive weighting were also considered. Results The OP-SVM algorithm and its cost-sensitive variant achieved the highest area under the receiver operating characteristic curve for the majority of the PCI complications studied (eight cases). Similar improvements were observed for the Hosmer–Lemeshow χ2 value (seven cases) and the mean cross-entropy error (eight cases). Conclusions The OP-SVM algorithm based on an augmented one-class learning problem improved discrimination and calibration across different PCI complications relative to LR and traditional support vector machine classification. Such an approach may have value in a broader range of clinical domains. PMID:23599229
NASA Astrophysics Data System (ADS)
Zhou, Yijie; Huang, Aibin; Zhou, Huaijuan; Ji, Shidong; Jin, Ping
2018-03-01
Research on functional flexible films has recently been attracting widespread attention especially with regards to foils, which can be designed artificially on the basis of the practical requirements. In this work, a foil with high visible reflection and a strong near infrared shielding efficiency was prepared by a simple wet chemical method. In the process of making this kind of optical foil, emulsion polymerization was first introduced to synthesize polymer opals, which were further compressed between two pieces of polyethylene terephthalate (PET) foil under polymer melting temperature to obtain a photonic crystal film with a strong reflection in the visible region to block blue rays. The following step was to coat a layer of the inorganic nano paint, which was synthesized by dispersing Cs-doped WO3 (CWO) nanoparticles homogenously into organic resin on the surface of the PET to achieve a high near infrared shielding ability. The final composite foil exhibited unique optical properties such as high visible reflectance (23.9%) to block blue rays, and excellent near infrared shielding efficiency (98.0%), meanwhile it still maintained a high transparency meaning that this foil could potentially be applied in energy-saving window films. To sum up, this study provides new insight into devising flexible hybrid films with novel optical properties, which could be further extended to prepare other optical films for potential use in automobile, architectural and other decorative fields.
NASA Astrophysics Data System (ADS)
Pescarini, M.; Sinitsa, V.; Orsi, R.; Frisoni, M.
2013-03-01
This paper presents a synthesis of the ENEA-Bologna Nuclear Data Group programme dedicated to generate and validate group-wise cross section libraries for shielding and radiation damage deterministic calculations in nuclear fission reactors, following the data processing methodology recommended in the ANSI/ANS-6.1.2-1999 (R2009) American Standard. The VITJEFF311.BOLIB and VITENDF70.BOLIB finegroup coupled n-γ (199 n + 42 γ - VITAMIN-B6 structure) multi-purpose cross section libraries, based on the Bondarenko method for neutron resonance self-shielding and respectively on JEFF-3.1.1 and ENDF/B-VII.0 evaluated nuclear data, were produced in AMPX format using the NJOY-99.259 and the ENEA-Bologna 2007 Revision of the SCAMPI nuclear data processing systems. Two derived broad-group coupled n-γ (47 n + 20 γ - BUGLE-96 structure) working cross section libraries in FIDO-ANISN format for LWR shielding and pressure vessel dosimetry calculations, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, were generated by the revised version of SCAMPI, through problem-dependent cross section collapsing and self-shielding from the cited fine-group libraries. The validation results on the criticality safety benchmark experiments for the fine-group libraries and the preliminary validation results for the broad-group working libraries on the PCA-Replica and VENUS-3 engineering neutron shielding benchmark experiments are reported in synthesis.
Evaluation of IdaShield sign safety benefits at highway-rail crossing in Idaho.
DOT National Transportation Integrated Search
2014-11-01
This report describes findings from a study aimed at assessing the safety impact of IdaShield signs installed at 1,341 highway : railroad crossings in Idaho. Specifically, our research assessed the markers effectiveness using three measures: : ...
The dominant firm in health insurance.
Goldberg, L G; Greenberg, W
1985-01-01
Blue Cross, the largest insurer of hospital costs in most parts of the U.S., has a varying market share by area. This paper examines the factors affecting the market share of Blue Cross by state. The regression analysis finds that the Blue Cross discount has an important impact upon market structure and that certain regulatory factors have had an impact while others, such as the premium tax, have not. Hypotheses related to the effects of consumer demand and the structure of the industry on Blue Cross market share are also tested and largely rejected.
Austin, S Bryn; Spadano-Gasbarro, Jennifer L; Greaney, Mary L; Blood, Emily A; Hunt, Anne T; Richmond, Tracy K; Wang, Monica L; Mezgebu, Solomon; Osganian, Stavroula K; Peterson, Karen E
2012-01-01
The Planet Health obesity prevention curriculum has prevented purging and abuse of diet pills (disordered weight control behavior [DWCB]) in middle-school girls in randomized trials, but the effects of Planet Health on DWCB when implemented by schools under dissemination conditions are not known. Massachusetts Department of Public Health and Blue Cross Blue Shield of Massachusetts disseminated Planet Health as part of the 3-year, Healthy Choices obesity prevention program in middle schools. We conducted an evaluation in 45 schools from fall 2005 to spring 2008. We gathered data from school staff to quantify intervention activities, and we gathered anonymous cross-sectional survey data from students on DWCB at baseline and Year 3 follow-up (n = 16,369). Multivariate logistic analyses with generalized estimating equations examined the effect of intervention activities on odds of students reporting DWCB at follow-up. Students in schools reaching a high number of youth with Planet Health lessons on reducing television viewing had lower odds of DWCB at follow-up (odds ratio [OR], 0.80 per 100 lesson-exposures; 95% confidence interval [CI], 0.74-0.85). In addition, reduced odds of DWCB at follow-up were found in schools with active staff teamwork (OR, 0.76; 95% CI, 0.66-0.86) and the presence of programs addressing television viewing goals with staff (OR, 0.38; 95% CI, 0.28-0.53). Combined evidence from efficacy and effectiveness trials and now from dissemination research indicates that appropriately designed obesity prevention programs can achieve DWCB prevention on a large scale.
Development of a claims-based risk score to identify obese individuals.
Clark, Jeanne M; Chang, Hsien-Yen; Bolen, Shari D; Shore, Andrew D; Goodwin, Suzanne M; Weiner, Jonathan P
2010-08-01
Obesity is underdiagnosed, hampering system-based health promotion and research. Our objective was to develop and validate a claims-based risk model to identify obese persons using medical diagnosis and prescription records. We conducted a cross-sectional analysis of de-identified claims data from enrollees of 3 Blue Cross Blue Shield plans who completed a health risk assessment capturing height and weight. The final sample of 71,057 enrollees was randomly split into 2 subsamples for development and validation of the obesity risk model. Using the Johns Hopkins Adjusted Clinical Groups case-mix/predictive risk methodology, we categorized study members' diagnosis (ICD) codes. Logistic regression was used to determine which claims-based risk markers were associated with a body mass index (BMI) > or = 35 kg/m(2). The sensitivities of the scores > or =90(th) percentile to detect obesity were 26% to 33%, while the specificities were >90%. The areas under the receiver operator curve ranged from 0.67 to 0.73. In contrast, a diagnosis of obesity or an obesity medication alone had very poor sensitivity (10% and 1%, respectively); the obesity risk model identified an additional 22% of obese members. Varying the percentile cut-point from the 70(th) to the 99(th) percentile resulted in positive predictive values ranging from 15.5 to 59.2. An obesity risk score was highly specific for detecting a BMI > or = 35 kg/m(2) and substantially increased the detection of obese members beyond a provider-coded obesity diagnosis or medication claim. This model could be used for obesity care management and health promotion or for obesity-related research.
Franzini, Luisa; White, Chapin; Taychakhoonavudh, Suthira; Parikh, Rohan; Zezza, Mark; Mikhail, Osama
2014-12-01
To measure the contribution of market-level prices, utilization, and health risk to medical spending variation among the Blue Cross Blue Shield of Texas (BCBSTX) privately insured population and the Texas Medicare population. Claims data for all BCBSTX members and publicly available CMS data for Texas in 2011. We used observational data and decomposed overall and service-specific spending into health status and health status adjusted utilization and input prices and input prices adjusted for the BCBSTX and Medicare populations. Variation in overall BCBSTX spending across HRRs appeared driven by price variation, whereas utilization variation factored more prominently in Medicare. The contribution of price to spending variation differed by service category. Price drove inpatient spending variation, while utilization drove outpatient and professional spending variation in BCBSTX. The context in which negotiations occur may help explain the patterns across services. The conventional wisdom that Medicare does a better job of controlling prices and private plans do a better job of controlling volume is an oversimplification. BCBSTX does a good job of controlling outpatient and professional prices, but not at controlling inpatient prices. Strategies to manage the variation in spending may need to differ substantially depending on the service and payer. © Health Research and Educational Trust.
Health insurers promoting employee wellness: strategies, program components and results.
Murphy, Brigid M; Schoenman, Julie A; Pirani, Hafiza
2010-01-01
To examine health insurance companies' role in employee wellness. Case studies of eight insurers. Wellness activities in work, clinical, online, and telephonic settings. Senior executives and wellness program leaders from Blue Cross Blue Shield health insurers and from one wellness organization. Telephone interviews with 20 informants. Health insurers were engaged in wellness as part of their mission to promote health and reduce health care costs. Program components included the following: education, health risk assessments, incentives, coaching, environmental consultation, targeted programming, onsite biometric screening, professional support, and full-time wellness staff. Programs relied almost exclusively on positive incentives to encourage participation. Results included participation rates as high as 90%, return on investment ranging from $1.09 to $1.65, and improved health outcomes. Health insurers have expertise in developing, implementing, and marketing health programs and have wide access to employers and their employees' health data. These capabilities make health insurers particularly well equipped to expand the reach of wellness programming to improve the health of many Americans. By coupling members' medical data with wellness-program data, health insurers can better understand an individual's health status to develop and deliver targeted interventions. Through program evaluation, health insurers can also contribute to the limited but growing evidence base on employee wellness programs.
Daylight savings time and myocardial infarction.
Sandhu, Amneet; Seth, Milan; Gurm, Hitinder S
2014-01-01
Prior research has shown a transient increase in the incidence of acute myocardial infarction (AMI) after daylight savings time (DST) in the spring as well as a decrease in AMI after returning to standard time in the fall. These findings have not been verified in a broader population and if extant, may have significant public health and policy implications. We assessed changes in admissions for AMI undergoing percutaneous coronary intervention (PCI) in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) database for the weeks following the four spring and three fall DST changes between March 2010 and September 2013. A negative binomial regression model was used to adjust for trend and seasonal variation. There was no difference in the total weekly number of PCIs performed for AMI for either the fall or spring time changes in the time period analysed. After adjustment for trend and seasonal effects, the Monday following spring time changes was associated with a 24% increase in daily AMI counts (p=0.011), and the Tuesday following fall changes was conversely associated with a 21% reduction (p=0.044). No other weekdays in the weeks following DST changes demonstrated significant associations. In the week following the seasonal time change, DST impacts the timing of presentations for AMI but does not influence the overall incidence of this disease.
An innovative approach to reducing medical care utilization and expenditures.
Orme-Johnson, D W; Herron, R E
1997-01-01
In a retrospective study, we assessed the impact on medical utilization and expenditures of a multicomponent prevention program, the Maharishi Vedic Approach to Health (MVAH). We compared archival data from Blue Cross/Blue Shield Iowa for MVAH (n = 693) with statewide norms for 1985 through 1995 (n = 600,000) and with a demographically matched control group (n = 4,148) for 1990, 1991, 1994, and 1995. We found that the 4-year total medical expenditures per person in the MVAH group were 59% and 57% lower than those in the norm and control groups, respectively; the 11-year mean was 63% lower than the norm. The MVAH group had lower utilization and expenditures across all age groups and for all disease categories. Hospital admission rates in the control group were 11.4 times higher than those in the MVAH group for cardiovascular disease, 3.3 times higher for cancer, and 6.7 times higher for mental health and substance abuse. The greatest savings were seen among MVAH patients older than age 45, who had 88% fewer total patients days compared with control patients. Our results confirm previous research supporting the effectiveness of MVAH for preventing disease. Our evaluation suggests that MVAH can be safely used as a cost-effective treatment regimen in the managed care setting.
Cama, Shireen; Malowney, Monica; Smith, Anna Jo Bodurtha; Spottswood, Margaret; Cheng, Elisa; Ostrowsky, Louis; Rengifo, Jose; Boyd, J Wesley
2017-10-01
The authors sought to assess the availability of outpatient mental health care through pediatrician and child psychiatrist offices in the United States and to characterize differences in appointment availability by location, provider type, and insurance across five cities. To do so, the authors posed as parents of a 12-year-old child with depression, gave a predetermined insurance type, and asked to make the first available appointment with the specified provider. They called the offices of 601 individual pediatricians and 312 child psychiatrists located in five U.S. cities and listed as in-network by Blue Cross Blue Shield, one of the largest private insurers in the United States. Appointments were obtained with 40% of the pediatricians and 17% of the child psychiatrists. The mean wait time for psychiatry appointments was 30 days longer than for pediatric appointments. Providers were less likely to have available appointments for children on Medicaid, which is public insurance for low-income people. The most common reason for being unable to make an appointment was that the listed phone number was incorrect. Pediatricians were twice as likely to see new patients and to see them sooner than child psychiatrists. Increasing the number of both types of providers may be necessary to increase access to mental health care for children.
Physicians, payers, and power. The United States is witnessing a struggle for control of healthcare.
Friedman, E
1995-01-01
From its earliest days, healthcare in the United States has been controlled by providers, that is, by physicians and by hospitals (which, in turn, were also usually controlled by physicians). But this situation is changing. In the 1920s and 1930s, providers created health insurance companies like Blue Cross and Blue Shield to help patients pay for healthcare--to pay, in other words, for those services offered by providers. After World War II, the Hill-Burton program covered the nation with new hospitals. In the 1960s, Medicare and Medicaid eased the healthcare burden of older Americans--and also recapitalized hospitals. Thus providers called the shots in the creation of both the delivery and the payment systems. But in the 1970s, payers began to become more powerful. Now, in the 1990s, they have joined employers in acting to contain rapidly escalating healthcare costs. But even those long disturbed by the arrogance of some healthcare providers are now asking themselves: Is this really what we wanted? Payers are governed by the market; they may well seek, not the best, but the cheapest healthcare available. This is not in the interest of either patients or physicians. A middle ground--a new power alignment--will have to be worked out by patients, physicians, payers, and government.
Assessment and measurement of patient-centered medical home implementation: the BCBSM experience.
Alexander, Jeffrey A; Paustian, Michael; Wise, Christopher G; Green, Lee A; Fetters, Michael D; Mason, Margaret; El Reda, Darline K
2013-01-01
Our goal was to describe an approach to patient-centered medical home (PCMH) measurement based on delineating the desired properties of the measurement relative to assumptions about the PCMH and the uses of the measure by Blue Cross Blue Shield of Michigan (BCBSM) and health services researchers. We developed and validated an approach to assess 13 functional domains of PCMHs and 128 capabilities within those domains. A measure of PCMH implementation was constructed using data from the validated self-assessment and then tested on a large sample of primary care practices in Michigan. Our results suggest that the measure adequately addresses the specific requirements and assumptions underlying the BCBSM PCMH program-ability to assess change in level of implementation; ability to compare across practices regardless of size, affiliation, or payer mix; and ability to assess implementation of the PCMH through different sequencing of capabilities and domains. Our experience illustrates that approaches to measuring PCMH should be driven by the measures' intended use(s) and users, and that a one-size-fits-all approach may not be appropriate. Rather than promoting the BCBSM PCMH measure as the gold standard, our study highlights the challenges, strengths, and limitations of developing a standardized approach to PCMH measurement.
Song, Zirui; Safran, Dana Gelb; Landon, Bruce E; Landrum, Mary Beth; He, Yulei; Mechanic, Robert E; Day, Matthew P; Chernew, Michael E
2012-08-01
Seven provider organizations in Massachusetts entered the Blue Cross Blue Shield Alternative Quality Contract in 2009, followed by four more organizations in 2010. This contract, based on a global budget and pay-for-performance for achieving certain quality benchmarks, places providers at risk for excessive spending and rewards them for quality, similar to the new Pioneer Accountable Care Organizations in Medicare. We analyzed changes in spending and quality associated with the Alternative Quality Contract and found that the rate of increase in spending slowed compared to control groups, more so in the second year than in the first. Overall, participation in the contract over two years led to savings of 2.8 percent (1.9 percent in year 1 and 3.3 percent in year 2) compared to spending in nonparticipating groups. Savings were accounted for by lower prices achieved through shifting procedures, imaging, and tests to facilities with lower fees, as well as reduced utilization among some groups. Quality of care also improved compared to control organizations, with chronic care management, adult preventive care, and pediatric care within the contracting groups improving more in year 2 than in year 1. These results suggest that global budgets with pay-for-performance can begin to slow underlying growth in medical spending while improving quality of care.
Maurana, Cheryl A; Lucey, Paula A; Ahmed, Syed M; Kerschner, Joseph E; Bolton, G Allen; Raymond, John R
2016-01-01
Health care conversion foundations, such as the Advancing a Healthier Wisconsin Endowment (the endowment) at the Medical College of Wisconsin (MCW), result from the conversion of nonprofit health organizations to for-profit corporations. Over the past several decades, nearly 200 of these foundations have been created, and they have had a substantial impact on the field of health philanthropy. The MCW was a recipient of funds resulting from Blue Cross & Blue Shield United of Wisconsin's conversion from a nonprofit to a for-profit status in 1999. Established in 2004, the endowment has invested approximately $185 million in 337 research, education, and public and community health initiatives that benefit Wisconsin residents. However, the transformative potential of the health care conversion foundation has extended well beyond the opportunities provided through the endowment's financial resources. As the endowment celebrates its 10th anniversary, the authors describe the transformative nature of the endowment, as well as significant accomplishments and lessons learned, in the following areas: shared power, community partnerships, translational research, and integration of medicine and public health. It is the authors' hope that these lessons will be valuable to other medical schools and the communities they serve, as they invest in improving the health of their communities, irrespective of the funding source.
Franzini, Luisa; White, Chapin; Taychakhoonavudh, Suthira; Parikh, Rohan; Zezza, Mark; Mikhail, Osama
2014-01-01
Objective To measure the contribution of market-level prices, utilization, and health risk to medical spending variation among the Blue Cross Blue Shield of Texas (BCBSTX) privately insured population and the Texas Medicare population. Data Sources Claims data for all BCBSTX members and publicly available CMS data for Texas in 2011. Study Design We used observational data and decomposed overall and service-specific spending into health status and health status adjusted utilization and input prices and input prices adjusted for the BCBSTX and Medicare populations. Principal Findings Variation in overall BCBSTX spending across HRRs appeared driven by price variation, whereas utilization variation factored more prominently in Medicare. The contribution of price to spending variation differed by service category. Price drove inpatient spending variation, while utilization drove outpatient and professional spending variation in BCBSTX. The context in which negotiations occur may help explain the patterns across services. Conclusions The conventional wisdom that Medicare does a better job of controlling prices and private plans do a better job of controlling volume is an oversimplification. BCBSTX does a good job of controlling outpatient and professional prices, but not at controlling inpatient prices. Strategies to manage the variation in spending may need to differ substantially depending on the service and payer. PMID:24919408
Wende, Charles W. J.
1976-08-17
A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.
Validity of Hansen-Roach cross sections in low-enriched uranium systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Busch, R.D.; O'Dell, R.D.
Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in crossmore » sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.« less
Aerothermodynamic optimization of Earth entry blunt body heat shields for Lunar and Mars return
NASA Astrophysics Data System (ADS)
Johnson, Joshua E.
A differential evolutionary algorithm has been executed to optimize the hypersonic aerodynamic and stagnation-point heat transfer performance of Earth entry heat shields for Lunar and Mars return manned missions with entry velocities of 11 and 12.5 km/s respectively. The aerothermodynamic performance of heat shield geometries with lift-to-drag ratios up to 1.0 is studied. Each considered heat shield geometry is composed of an axial profile tailored to fit a base cross section. Axial profiles consist of spherical segments, spherically blunted cones, and power laws. Heat shield cross sections include oblate and prolate ellipses, rounded-edge parallelograms, and blendings of the two. Aerothermodynamic models are based on modified Newtonian impact theory with semi-empirical correlations for convection and radiation. Multi-objective function optimization is performed to determine optimal trade-offs between performance parameters. Objective functions consist of minimizing heat load and heat flux and maximizing down range and cross range. Results indicate that skipping trajectories allow for vehicles with L/D = 0.3, 0.5, and 1.0 at lunar return flight conditions to produce maximum cross ranges of 950, 1500, and 3000 km respectively before Qs,tot increases dramatically. Maximum cross range increases by ˜20% with an increase in entry velocity from 11 to 12.5 km/s. Optimal configurations for all three lift-to-drag ratios produce down ranges up to approximately 26,000 km for both lunar and Mars return. Assuming a 10,000 kg mass and L/D = 0.27, the current Orion configuration is projected to experience a heat load of approximately 68 kJ/cm2 for Mars return flight conditions. For both L/D = 0.3 and 0.5, a 30% increase in entry vehicle mass from 10,000 kg produces a 20-30% increase in Qs,tot. For a given L/D, highly-eccentric heat shields do not produce greater cross range or down range. With a 5 g deceleration limit and L/D = 0.3, a highly oblate cross section with an eccentricity of 0.968 produces a 35% reduction in heat load over designs with zero eccentricity due to the eccentric heat shield's greater drag area that allows the vehicle to decelerate higher in the atmosphere. In this case, the heat shield's drag area is traded off with volumetric efficiency while fulfilling the given set of mission requirements. Additionally, the high radius-of-curvature of the spherical segment axial profile provides the best combination of heat transfer and aerodynamic performance for both entry velocities and a 5 g deceleration limit.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Myoung-Jae; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180-3590
2015-10-15
The quantum diffraction and shielding effects on the low-energy bremsstrahlung process are investigated in two-component semiclassical plasmas. The impact-parameter analysis with the micropotential taking into account the quantum diffraction and shielding effects is employed to obtain the electron-ion bremsstrahlung radiation cross section as a function of the de Broglie wavelength, density parameter, impact parameter, photon energy, and projectile energy. The result shows that the influence of quantum diffraction and shielding strongly suppresses the bremsstrahlung radiation spectrum in semiclassical plasmas. It is found that the quantum diffraction and shielding effects have broaden the photon emission domain. It is also found thatmore » the photon emission domain is almost independent of the radiation photon energy. In addition, it is found that the influence of quantum diffraction and shielding on the bremsstrahlung spectrum decreases with an increase of the projectile energy. The density effect on the electron-ion bremsstrahlung cross section is also discussed.« less
Code of Federal Regulations, 2013 CFR
2013-04-01
... the use of, or assistance from, a brace, cane, crutch, another person, prosthetic device, wheelchair..., centered on the placard, and is white on a blue shield; (2) An identification number; (3) A date of... Symbol of Access, which is at least three inches in height, centered on the placard, and is white on a...
Code of Federal Regulations, 2011 CFR
2011-04-01
... the use of, or assistance from, a brace, cane, crutch, another person, prosthetic device, wheelchair..., centered on the placard, and is white on a blue shield; (2) An identification number; (3) A date of... Symbol of Access, which is at least three inches in height, centered on the placard, and is white on a...
Code of Federal Regulations, 2014 CFR
2014-04-01
... the use of, or assistance from, a brace, cane, crutch, another person, prosthetic device, wheelchair..., centered on the placard, and is white on a blue shield; (2) An identification number; (3) A date of... Symbol of Access, which is at least three inches in height, centered on the placard, and is white on a...
Code of Federal Regulations, 2012 CFR
2012-04-01
... the use of, or assistance from, a brace, cane, crutch, another person, prosthetic device, wheelchair..., centered on the placard, and is white on a blue shield; (2) An identification number; (3) A date of... Symbol of Access, which is at least three inches in height, centered on the placard, and is white on a...
Code of Federal Regulations, 2010 CFR
2010-04-01
... the use of, or assistance from, a brace, cane, crutch, another person, prosthetic device, wheelchair..., centered on the placard, and is white on a blue shield; (2) An identification number; (3) A date of... Symbol of Access, which is at least three inches in height, centered on the placard, and is white on a...
DCCA cross-correlation in blue-chips companies: A view of the 2008 financial crisis in the Eurozone
NASA Astrophysics Data System (ADS)
Guedes, E.; Dionísio, A.; Ferreira, P. J.; Zebende, G. F.
2017-08-01
In this paper we analyze the blue-chips (up to 50% of the total index) companies in the Eurozone. Our motivation being analysis of the effect of the 2008 financial crisis. For this purpose, we apply the DCCA cross-correlation coefficient (ρDCCA) between the country stock market index and their respective blue-chips. Then, with the cross-correlation coefficient, we qualify and quantify how each blue-chip is adherent to its country index, evaluating the type of cross-correlation among them. Subsequently, for each blue-chip, we propose to study the 2008 financial crisis by measuring the adherence between post and pre-crisis. From this analysis, we can construct an adhesion map of each company with respect to the global index. Our database is formed of 12 Eurozone countries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saygin, H.; Hebert, A.
The calculation of a dilution cross section {bar {sigma}}{sub e} is the most important step in the self-shielding formalism based on the equivalence principle. If a dilution cross section that accurately characterizes the physical situation can be calculated, it can then be used for calculating the effective resonance integrals and obtaining accurate self-shielded cross sections. A new technique for the calculation of equivalent cross sections based on the formalism of Riemann integration in the resolved energy domain is proposed. This new method is compared to the generalized Stamm`ler method, which is also based on an equivalence principle, for a two-regionmore » cylindrical cell and for a small pressurized water reactor assembly in two dimensions. The accuracy of each computing approach is obtained using reference results obtained from a fine-group slowing-down code named CESCOL. It is shown that the proposed method leads to slightly better performance than the generalized Stamm`ler approach.« less
Polarization momentum transfer collision: Faxen-Holtzmark theory and quantum dynamic shielding.
Ki, Dae-Han; Jung, Young-Dae
2013-04-21
The influence of the quantum dynamic shielding on the polarization momentum transport collision is investigated by using the Faxen-Holtzmark theory in strongly coupled Coulomb systems. The electron-atom polarization momentum transport cross section is derived as a function of the collision energy, de Broglie wavelength, Debye length, thermal energy, and atomic quantum states. It is found that the dynamic shielding enhances the scattering phase shift as well as the polarization momentum transport cross section. The variation of quantum effect on the momentum transport collision due to the change of thermal energy and de Broglie wavelength is also discussed.
Pennsylvania Blue Shield Job Linked Skills Program. Teacher's Manual [and] Technical Manual.
ERIC Educational Resources Information Center
Pennsylvania State Univ., University Park. Inst. for the Study of Adult Literacy.
Two closely related publications from the same project, a Teacher's Manual" and a "Technical Manual", are combined here. These manuals are intended to accompany a work force literacy course designed to meet the basic skills needs of midliterate adults employed or preparing for employment in the health insurance industry.…
NASA Astrophysics Data System (ADS)
Lee, Myoung-Jae; Jung, Young-Dae
2017-05-01
The influence of nonisothermal and quantum shielding on the electron-ion collision process is investigated in strongly coupled two-temperature plasmas. The eikonal method is employed to obtain the eikonal scattering phase shift and eikonal cross section as functions of the impact parameter, collision energy, electron temperature, ion temperature, Debye length, and de Broglie wavelength. The results show that the quantum effect suppresses the eikonal scattering phase shift for the electron-ion collision in two-temperature dense plasmas. It is also found that the differential eikonal cross section decreases for small impact parameters. However, it increases for large impact parameters with increasing de Broglie wavelength. It is also found that the maximum position of the differential eikonal cross section is receded from the collision center with an increase in the nonisothermal character of the plasma. In addition, it is found that the total eikonal cross sections in isothermal plasmas are always greater than those in two-temperature plasmas. The variations of the eikonal cross section due to the two-temperature and quantum shielding effects are also discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Yuxuan; Martin, William; Williams, Mark
In this paper, a correction-based resonance self-shielding method is developed that allows annular subdivision of the fuel rod. The method performs the conventional iteration of the embedded self-shielding method (ESSM) without subdivision of the fuel to capture the interpin shielding effect. The resultant self-shielded cross sections are modified by correction factors incorporating the intrapin effects of radial variation of the shielded cross section, radial temperature distribution, and resonance interference. A quasi–one-dimensional slowing-down equation is developed to calculate such correction factors. The method is implemented in the DeCART code and compared with the conventional ESSM and subgroup method with benchmark MCNPmore » results. The new method yields substantially improved results for both spatially dependent reaction rates and eigenvalues for typical pressurized water reactor pin cell cases with uniform and nonuniform fuel temperature profiles. Finally, the new method is also proved effective in treating assembly heterogeneity and complex material composition such as mixed oxide fuel, where resonance interference is much more intense.« less
NASA Astrophysics Data System (ADS)
Endo, Y.; Ogawa, M.; Danielache, S. O.; Ueno, Y.
2017-12-01
Archean sulfur mass-independent fractionation (S-MIF) is a unique proxy within the geological and geochemical records for studying the composition of the Archean atmosphere. S-MIF signatures are defined as Δ33S = δ33S - 0.515×δ34S and Δ36S = δ36S - 1.90×δ34S. Archean S-MIF is characterized as Δ36S/Δ33S = -1. Recent SO2 photochemical experiments under specific reducing conditions reproduced the Archean trend for the first time [1]. Self-shielding of SO2 photolysis and intersystem crossing in excited SO2 are probably key mechanisms for explaining Archean S-MIF. Self-shielding is originated from UV spectra changed by upper SO2 own absorption. Because 32S accounts for about 95% of all sulfur isotopes, the photolysis rate constant of only 32SO2 is lower than other isotopologue. Thus, SO2 photolysis in the bottom of the atmosphere undergoes mass-independent fractionation. Fractionation factors by SO2 photolysis reaction can be calculated by absorption cross-sections of 32SO2, 33SO2, 34SO2 and 36SO2 and respective quantum yields. Quantitative estimations self-shielding fractionation factors requires high-spectral resolution cross-sections, but they have not been reported yet. Here we report measurements of high-resolution cross-sections (1cm-1) and fractionation factors by SO2 photolysis including self-shielding. Moreover, because the absorption wavelength varies with each isotopologue, photolysis rate constants of all isotopologues (32S16O2, 32S16O18O, etc) should be different. Then self-shielding may affect the ratio of isotopologues such as clumped-isotopes. We calculated preliminary calculation clumped isotope enrichment in residual species by self-shielding. Reference: [1] Endo, Y., Ueno, Y., Aoyama, S., & Danielache, S. O. (2016). Sulfur isotope fractionation by broadband UV radiation to optically thin SO2 under reducing atmosphere. EPSL, 453, 9-22.
The effects of premium changes on ALL Kids, Alabama's CHIP program.
Morrisey, Michael A; Blackburn, Justin; Sen, Bisakha; Becker, David; Kilgore, Meredith L; Caldwell, Cathy; Menachemi, Nir
2012-01-01
Describe the trends in enrollment and renewal in the Alabama Children's Health Insurance Plan (CHIP), ALL Kids, since its creation in 1998, and to estimate the effect that an annual premium increase, along with coincident increases in service copays, had on the decision to renew participation. Unlike many other CHIP programs, ALL Kids is a standalone program that provides year long enrollment and contracts with the state's Blue Cross and Blue Shield program for its network of providers and its provider fee structure. In October 2003 premiums for individual coverage were increased by $50 per year and copays by $1 to $3 per visit. This study is based upon a sample of 569,650 person-year observations of 230,255 children enrolled in the ALL Kids program between 1999 and 2009. The study models enrollment as a time series of cross section renewal decisions and specifies a series of linear probability regression models to estimate the effect of changes in the premium shift on the decision to renew. A second analysis includes interaction effects of the premiums shift with demographics, health status, income and previous enrollment to estimate differential response across subgroups. The increases in premiums and copays are estimated to have reduced program renewals by 6.1 to 8.3 percent depending upon how much time one allows for families to renew. Families with a child who has a chronic condition were more likely to renew coverage. However, those with chronic conditions, African-Americans and those with lower family incomes were more price-sensitive. An increase in annual premiums and visit copays had a modest impact on program reenrollment with effects comparable to those found in Florida, New Hampshire, Kansas and Arizona, but smaller than those in Kentucky and Georgia.
Spadano-Gasbarro, Jennifer L.; Greaney, Mary L.; Blood, Emily A.; Hunt, Anne T.; Richmond, Tracy K.; Wang, Monica L.; Mezgebu, Solomon; Osganian, Stavroula K.; Peterson, Karen E.
2012-01-01
Introduction The Planet Health obesity prevention curriculum has prevented purging and abuse of diet pills (disordered weight control behavior [DWCB]) in middle-school girls in randomized trials, but the effects of Planet Health on DWCB when implemented by schools under dissemination conditions are not known. Methods Massachusetts Department of Public Health and Blue Cross Blue Shield of Massachusetts disseminated Planet Health as part of the 3-year, Healthy Choices obesity prevention program in middle schools. We conducted an evaluation in 45 schools from fall 2005 to spring 2008. We gathered data from school staff to quantify intervention activities, and we gathered anonymous cross-sectional survey data from students on DWCB at baseline and Year 3 follow-up (n = 16,369). Multivariate logistic analyses with generalized estimating equations examined the effect of intervention activities on odds of students reporting DWCB at follow-up. Results Students in schools reaching a high number of youth with Planet Health lessons on reducing television viewing had lower odds of DWCB at follow-up (odds ratio [OR], 0.80 per 100 lesson-exposures; 95% confidence interval [CI], 0.74–0.85). In addition, reduced odds of DWCB at follow-up were found in schools with active staff teamwork (OR, 0.76; 95% CI, 0.66–0.86) and the presence of programs addressing television viewing goals with staff (OR, 0.38; 95% CI, 0.28–0.53). Conclusion Combined evidence from efficacy and effectiveness trials and now from dissemination research indicates that appropriately designed obesity prevention programs can achieve DWCB prevention on a large scale. PMID:23194779
An intrinsically shielded hydrogel for the adsorptive recovery of lysozyme.
Wang, Lu; Zhang, Rongsheng; Eisenthal, Robert; Hubble, John
2006-07-01
The present paper addresses the selective recovery of lysozyme from egg white using CM-dextran (carboxymethyldextran)-based hydrogels containing Cibacron Blue as an affinity ligand and co-immobilized BSA intended to act as a shielding agent to reduce non-specific adsorption. Initial studies using pure lysozyme were conducted that indicated that the adsorption capacity increased with ligand density and that adsorption was well described by a Langmuir-type isotherm. The inclusion of BSA as a putative shielding agent did not decrease the adsorption capacity for lysozyme in single-adsorbate experiments. To assess the effectiveness of the shielding strategy, subsequent experiments were conducted with both defined lysozyme/ovalbumin mixtures and hen's-egg white. From these studies, the optimal operating conditions for lysozyme recovery have been determined. These include: optimal initial egg-white concentration [a 10% (v/v) solution of native egg white in the chosen buffer], affinity-ligand density (1.86 mM) and ligand-to-shielding-agent ratio (4:1). The purity of lysozyme obtained from egg white was improved from 69% with a non-shielded hydrogel to 94% with an intrinsically shielded hydrogel. Finally, the possibility of using a protein, rather than dextran-backbone-based, hydrogel was investigated. It was found that BSA could take the place of CM-dextran as the gel backbone in a simplified synthesis, producing a gel which also proved effective for lysozyme recovery with a 30% lysozyme in egg-white solution purified to approx. 92% in a single adsorption-desorption cycle.
Prato, Frank S; Desjardins-Holmes, Dawn; Keenliside, Lynn D; McKay, Julia C; Robertson, John A; Thomas, Alex W
2008-01-01
Previous experiments with mice have shown that repeated 1 hour daily exposure to an ambient magnetic field-shielded environment induces analgesia (antinociception). The exposures were carried out in the dark (less than 2.0×1016 photons s−1 m−2) during the mid-light phase of the diurnal cycle. However, if the mice were exposed in the presence of visible light (2.0×1018 photons s−1 m−2, 400–750 nm), then the analgesic effects of shielding were eliminated. Here, we show that this effect of light is intensity and wavelength dependent. Introduction of red light (peak at 635 nm) had little or no effect, presumably because mice do not have photoreceptors sensitive to red light above 600 nm in their eyes. By contrast, introduction of ultraviolet light (peak at 405 nm) abolished the effect, presumably because mice do have ultraviolet A receptors. Blue light exposures (peak at 465 nm) of different intensities demonstrate that the effect has an intensity threshold of approximately 12% of the blue light in the housing facility, corresponding to 5×1016 photons s−1 m−2 (integral). This intensity is similar to that associated with photoreceptor-based magnetoreception in birds and in mice stimulates photopic/cone vision. Could the detection mechanism that senses ambient magnetic fields in mice be similar to that in bird navigation? PMID:18583276
Gamma heating in reflector heat shield of gas core reactor
NASA Technical Reports Server (NTRS)
Lofthouse, J. H.; Kunze, J. F.; Young, T. E.; Young, R. C.
1972-01-01
Heating rate measurements made in a mock-up of a BeO heat shield for a gas core nuclear rocket engine yields results nominally a factor of two greater than calculated by two different methods. The disparity is thought to be caused by errors in neutron capture cross sections and gamma spectra from the low cross-section elements, D, O, and Be.
Gabel, Jon R; Whitmore, Heidi; Green, Matthew; Stromberg, Sam T; Weinstein, Daniel S; Oran, Rebecca
2015-12-01
Premiums for health insurance plans offered through the federally facilitated and state-based Marketplaces remained steady or increased only modestly from 2014 to 2015. We used data from the Marketplaces, state insurance departments, and insurer websites to examine patterns of premium pricing and the factors behind these patterns. Our data came from 2,964 unique plans offered in 2014 and 4,153 unique plans offered in 2015 in forty-nine states and the District of Columbia. Using descriptive and multivariate analysis, we found that the addition of a carrier in a rating area lowered average premiums for the two lowest-cost silver plans and the lowest-cost bronze plan by 2.2 percent. When all plans in a rating area were included, an additional carrier was associated with an average decline in premiums of 1.4 percent. Plans in the Consumer Operated and Oriented Plan Program and Medicaid managed care plans had lower premiums and average premium increases than national commercial and Blue Cross and Blue Shield plans. On average, premiums fell by an appreciably larger amount for catastrophic and bronze plans than for gold plans, and premiums for platinum plans increased. This trend of low premium increases overall is unlikely to continue, however, as insurers are faced with mounting medical claims. Project HOPE—The People-to-People Health Foundation, Inc.
Daylight savings time and myocardial infarction
Sandhu, Amneet; Seth, Milan; Gurm, Hitinder S
2014-01-01
Background Prior research has shown a transient increase in the incidence of acute myocardial infarction (AMI) after daylight savings time (DST) in the spring as well as a decrease in AMI after returning to standard time in the fall. These findings have not been verified in a broader population and if extant, may have significant public health and policy implications. Methods We assessed changes in admissions for AMI undergoing percutaneous coronary intervention (PCI) in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) database for the weeks following the four spring and three fall DST changes between March 2010 and September 2013. A negative binomial regression model was used to adjust for trend and seasonal variation. Results There was no difference in the total weekly number of PCIs performed for AMI for either the fall or spring time changes in the time period analysed. After adjustment for trend and seasonal effects, the Monday following spring time changes was associated with a 24% increase in daily AMI counts (p=0.011), and the Tuesday following fall changes was conversely associated with a 21% reduction (p=0.044). No other weekdays in the weeks following DST changes demonstrated significant associations. Conclusions In the week following the seasonal time change, DST impacts the timing of presentations for AMI but does not influence the overall incidence of this disease. PMID:25332784
Rogowski, Wolf H; Hartz, Susanne C; John, Jürgen H
2008-09-24
New products evolving from research and development can only be translated to medical practice on a large scale if they are reimbursed by third-party payers. Yet the decision processes regarding reimbursement are highly complex and internationally heterogeneous. This study develops a process-oriented framework for monitoring these so-called fourth hurdle procedures in the context of product development from bench to bedside. The framework is suitable both for new drugs and other medical technologies. The study is based on expert interviews and literature searches, as well as an analysis of 47 websites of coverage decision-makers in England, Germany and the USA. Eight key steps for monitoring fourth hurdle procedures from a company perspective were determined: entering the scope of a healthcare payer; trigger of decision process; assessment; appraisal; setting level of reimbursement; establishing rules for service provision; formal and informal participation; and publication of the decision and supplementary information. Details are given for the English National Institute for Health and Clinical Excellence, the German Federal Joint Committee, Medicare's National and Local Coverage Determinations, and for Blue Cross Blue Shield companies. Coverage determination decisions for new procedures tend to be less formalized than for novel drugs. The analysis of coverage procedures and requirements shows that the proof of patient benefit is essential. Cost-effectiveness is likely to gain importance in future.
Physical inactivity: direct cost to a health plan.
Garrett, Nancy A; Brasure, Michelle; Schmitz, Kathryn H; Schultz, Monica M; Huber, Michael R
2004-11-01
The purpose of this study was to estimate the total medical expenditures attributable to physical inactivity patterns among members of a large health plan, Blue Cross Blue Shield of Minnesota. The study used a cost-of-illness approach to attribute medical and pharmacy costs for specific diseases to physical inactivity in 2000. Relative risks come from the scientific literature, demonstrating that heart disease, stroke, hypertension, type 2 diabetes, colon cancer, breast cancer, osteoporosis, depression, and anxiety are directly related to individual physical activity patterns in adults. Data sources were the 2000 Behavioral Risk Factor Surveillance System and medical claims incurred in 2000 among 1.5 million health plan members aged > or =18 years. Primary analysis was completed in 2002. Nearly 12% of depression and anxiety and 31% of colon cancer, heart disease, osteoporosis, and stroke cases were attributable to physical inactivity. Heart disease was the most expensive outcome of physical inactivity within the health plan population, costing US dollar 35.3 million in 2000. Total health plan expenditures attributable to physical inactivity were US dollar 83.6 million, or US dollar 56 per member. This study confirms the growing body of research quantifying physical inactivity as a serious and expensive public health problem. The costs associated with physical inactivity are borne by taxpayers, employers, and individuals in the form of higher taxes to subsidize public insurance programs and increased health insurance premiums.
Song, Zirui; Safran, Dana Gelb; Landon, Bruce E.; Landrum, Mary Beth; He, Yulei; Mechanic, Robert E.; Day, Matthew P.; Chernew, Michael E.
2012-01-01
Seven provider organizations in Massachusetts entered the Blue Cross Blue Shield Alternative Quality Contract in 2009, followed by four more organizations in 2010. This contract, based on a global budget and pay-for-performance for achieving certain quality benchmarks, places providers at risk for excessive spending and rewards them for quality, similar to the new Pioneer Accountable Care Organizations in Medicare. We analyzed changes in spending and quality associated with the Alternative Quality Contract and found that the rate of increase in spending slowed compared to control groups. Overall, participation in the contract over two years led to a savings of 3.3% (1.9% in year-1, 3.3% in year-2) compared to spending in groups not participating in the contract. The savings were even higher for groups whose previous experience had been only in fee-for-service contracting. Such groups’ quarterly savings over two years averaged 8.2% (6.3% in year-1, 9.9% in year-2). Quality of care also improved within organizations participating in the Alternative Quality Contract compared to control organizations in both years. Chronic care management, adult preventive care, and pediatric care improved from year 1 to year 2 within the contracting groups. These results suggest that global budgets coupled with pay-for-performance can begin to slow the underlying growth in medical spending while improving quality. PMID:22786651
Green, Lee A; Chang, Hsiu-Ching; Markovitz, Amanda R; Paustian, Michael L
2018-04-01
To determine whether the Patient-Centered Medical Home (PCMH) transformation reduces hospital and ED utilization, and whether the effect is specific to chronic conditions targeted for management by the PCMH in our setting. All patients aged 18 years and older in 2,218 primary care practices participating in a statewide PCMH incentive program sponsored by Blue Cross Blue Shield of Michigan (BCBSM) in 2009-2012. Quantitative observational study, jointly modeling PCMH-targeted versus other hospital admissions and ED visits on PCMH score, patient, and practice characteristics in a hierarchical multivariate model using the generalized gamma distribution. Claims data and PCMH scores held by BCBSM. Both hospital and ED utilization were reduced proportionately to PCMH score. Hospital utilization was reduced by 13.9 percent for PCMH-targeted conditions versus only 3.8 percent for other conditions (p = .003), and ED utilization by 11.2 percent versus 3.7 percent (p = .010). Hospital PMPM cost was reduced by 17.2 percent for PCMH-targeted conditions versus only 3.1 percent for other conditions (p < .001), and ED PMPM cost by 9.4 percent versus 3.6 percent (p < .001). PCMH transformation reduces hospital and ED use, and the majority of the effect is specific to PCMH-targeted conditions. © Health Research and Educational Trust.
NASA Technical Reports Server (NTRS)
Li, Zi-Wei; Adams, James H., Jr.
2007-01-01
Space radiation from galactic cosmic rays (GCR) is a major hazard to space crews, especially in long duration human space explorations. For this reason, they will be protected by radiation shielding that fragments the GCR heavy ions. Here we investigate how sensitive the crew's radiation exposure is to nuclear fragmentation cross sections at different energies. We find that in deep space cross sections between about 0.2 and 1.2 GeV/u have the strongest effect on dose equivalent behind shielding in solar minimum GCR environments, and cross sections between about 0.6 and 1.7 GeV/u are the most important at solar maximum'. On the other hand, at the location of the International Space Station, cross sections at_higher -energies, between about 0.6 and 1.7 GeV /u at solar minimum and between about 1.7 and 3.4 GeV/u'at,solar maximum, are the most important This is. due-to the average geomagnetic cutoff for the ISS orbit. We also show the effect of uncertainties in the fragmentation cross sections on the elemental energy spectra behind shielding. These results help to focus the studies of fragmentation cross sections on the proper energy range in order to improve our predictions of crew exposures.
NASA Technical Reports Server (NTRS)
Lin, Zi-wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most effect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space exploration.
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Jr., Charles G.; Cooper, Amy; Moore, Alastair S.
In order to prevent electromagnetic interference (EMI) from affecting the DISC diagnostic, an EMI shield was added. Figure 1 is a cross section from a CAD model of DISC and shows the EMI shield in situ. The shield is orange and at the top of the figure. Figure 2 is a drawing of just the EMI shield. The slit in the center of the EMI shield is covered by a metal mesh, which is not shown in this drawing. The small holes toward the base of the conical portion of the EMI shield are the pump-out holes, and the electromagneticmore » leakage through these holes is the subject of this report1. An alternate design for the EMI shield is considered in order to determine how to increase the EMI effectiveness of the pump-out holes in the shield without compromising the flow rate through the shield. Both the original and alternate designs are simulated and compared.« less
ERIC Educational Resources Information Center
Pennsylvania Blue Shield, Camp Hill.
A project developed a model curriculum to be delivered by computer-based instruction to teach the required literacy skills for entry workers in the health insurance industry. Literacy task analyses were performed for the targeted jobs and then validated with focus groups. The job tasks and related basic skills were divided into modules. The job…
Depositional environments and tectonic significance of the Wajid Sandstone of southern Saudi Arabia
NASA Astrophysics Data System (ADS)
Dabbagh, Mohamed E.; Rogers, John J. W.
The Wajid Sandstone, of probable Early Paleozoic age, rests disconformably on crystalline rocks of the southern part of the Arabian shield. Scattered outcrops extend over an area about 450 km north-south and 300 km east-west. The southern part of the formation, near the Yemen border, consists of fluvial sandstones and very minor siltstones and silty shales. The fluvial origin is demonstrated by the presence of fining-upward cycles, channels, trough cross bedding, and absence of all organic traces. The northern part of the outcrop area consists of internally homogeneous, tabular cross-bedded, horizontally bedded sandstones apparently formed in a shallow marine environment. These marine rocks contain trace fossils broadly similar to Skolithos. Abundant cross bedding in both facies of the Wajid indicates a northward transport direction, toward what is now the center of the Arabian shield. The southern part of the Arabian shield, which was cratonized about 500 to 600 Ma ago (Pan-African age), was apparently still a depositional area receiving sediments from a southern source in Early Paleozoic time. Other, older, shields also show a tendency to be areas of deposition shortly after their apparent age of stabilization, becoming sources of clastic sediments only after several hundreds of millions of years. The conversion from basin to uplifted source may indicate a prolonged process of shield maturation after initial stabilization.
For-profit conversion of Blue Cross plans: public benefit or public harm?
Hall, Mark A; Conover, Christopher J
2006-01-01
Conversions of Blue Cross plans to for-profit status have the potential to remake the corporate landscape of health care finance. Absent regulatory intervention, current trends could easily result in more than half of Blue Cross subscribers being in for-profit plans, a phenomenon far more significant than the conversion of nonprofit hospitals. Therefore, regulators' deliberations over conversion proposals are beginning to focus on the health policy impacts. This chapter surveys the full range of health policy implications by analyzing all existing studies of Blue Cross conversions and reporting on the authors' own case studies of conversion impacts. These studies conclude that conversions have not caused major negative impacts on the availability or accessibility of health care in the states in which conversions have occurred so far. However, a great deal of uncertainty exists about the actual effects of previous conversions, and each state is unique; therefore, even if the historical record were clear, it is difficult to predict with great certainty what the actual effects will be in another state undergoing a Blue conversion.
Neutron shielding behavior of thermoplastic natural rubber/boron carbide composites
NASA Astrophysics Data System (ADS)
Mat Zali, Nurazila; Yazid, Hafizal; Megat Ahmad, Megat Harun Al Rashid
2018-01-01
Many shielding materials have been designed against the harm of different types of radiation to the human body. Today, polymer-based lightweight composites have been chosen by the radiation protection industry. In the present study, thermoplastic natural rubber (TPNR) composites with different weight percent of boron carbide (B4C) fillers (0% to 30%) were fabricated as neutron shielding through melt blending method. Neutron attenuation properties of TPNR/B4C composites have been investigated. The macroscopic cross section (Σ), half value layer (HVL) and mean free path length (λ) of the composites have been calculated and the transmission curves have been plotted. The obtained results show that Σ, HVL and λ greatly depend on the B4C content. Addition of B4C fillers into TPNR matrix were found to enhance the macroscopic cross section values thus decrease the mean free path length (λ) and half value layer (HVL) of the composites. The transmission curves exhibited that the neutron transmission of the composites decreased with increasing shielding thickness. These results showed that TPNR/B4C composites have high potential for neutron shielding applications.
Study on the measures of tunnels side-crossing bridge based on sheltering effects of isolation piles
NASA Astrophysics Data System (ADS)
Tang, Jian; Liu, Jun yan; Liu, Yan
2017-08-01
Based on the transit line 3, we studied the effect of the bridge piles crossed closely from the side by the shield tunnel. Using the three-dimensional finite element numerical analysis software Midas GTS/NX, we analyzed the effect of shield tunnel on pile deformation, statistics are obtained that under the condition of pile, subgrade reinforcement and ground changes. The calculation results show that in the condition of reinforcement, the new tunnel shield crossing through the pile caused longitudinal disturbance of the tunnel surrounding strata along the tunnel, where the soil over the area is within a certain range of pile and settlement deformation of surface subsidence occurs, changing the surface roughly to the shape of “V”. The maximum value appears above the shield tunnel and the value is high. In combination with engineering geology, hydrogeology and environment factors, this paper adopted isolation pile reinforcement to the pile, and the simulated results show that, pile settlement was significantly reduced under the condition of pile reinforcement. The calculation results show the rationality of the reinforcement scheme to a certain extent, which provides a theoretical basis for the similar tunnel.
NASA Astrophysics Data System (ADS)
Wang, Qingjuan; Li, Can; Xu, Wenai; Zhao, Xiaolin; Zhu, Jingxin; Jiang, Haiwei; Kang, Litao; Zhao, Zhe
2017-03-01
Both Mo and W belong to VIB-sub-group, and possess similar ionic radii, electronegativity and oxide lattice configuration. Herein, Mo-doped (0-80 at.%) tungsten bronzes, MxWO3, were hydrothermally prepared to systematically explore the influence of Mo-doping on their micro-structure and optical performance. The products adopted a hexagonal structure within 6 at.% Mo-doping, and transformed into a monoclinic phase with higher Mo-doping content. Further tests suggested that 1.5 at.% Mo-doping is beneficial for the formation of pure hexagonal phase and uniform nano-rod morphology. Optical measures showed that all samples exhibited high and comparable visible transmittance (70-80%), but a very different near infrared (NIR) shielding ability. The sample doped with 1.5 at.% Mo demonstrated the best NIR shielding ability with a transmittance minimum of 20% at 1300 nm. Further increase of Mo-doping dosage remarkably deteriorated NIR shielding ability by depressing the absorption of localized surface plasmon resonance (LSPR). However, the optical absorption from small-polaron was less influenced by the introduction of Mo. As a result, Mo-doping caused an evident blue shift of the infrared absorption peaks from 1350 to 750 nm.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramasamy, Mohankandhasamy; Kim, Yu Jun; Gao, Haiyan
Graphical abstract: - Highlights: • Well layer thickness controlled silica shell was made on ZnO nanoparticles. • PEAA, an interfacial agent is used to make nanocomposite–polymer matrix by twin-screw extruder. • Si-ZnO/PEAA matrix is highly stable and UV protective as compared to ZnO/PEAA matrix. • Nanoparticle embedded polymer matrix is suggested to make UV shielding fabrics with Nylon4. - Abstract: Silica coated zinc oxide nanoparticles (Si-ZnO NPs) (7 nm thick) were synthesized successfully and melt blended with poly(ethylene-co-acrylic acid) (PEAA resin) to improving ultraviolet (UV) shielding of zinc oxide nanoparticles (ZnO NPs). The photostability of both the ZnO NPs andmore » Si-ZnO NPs were analyzed by the difference in photoluminescence (PL) and by methylene blue (MB) degradation. Photo-degradation studies confirmed that Si-ZnO NPs are highly photostable compared to ZnO NPs. The melt blended matrices were characterized by field emission scanning electron microscopy interfaced with energy dispersive X-ray spectroscopy (FE-SEM-EDX). The UV shielding property was analyzed from the transmittance spectra of UV–visible (UV–vis) spectroscopy. The results confirmed fine dispersion of thick Si-ZnO NPs in the entire resin matrix. Moreover, the Si-ZnO/PEAA showed about 97% UV shielding properties than the ZnO/PEAA.« less
Portable imaging system method and apparatus
Freifeld, Barry M.; Kneafsley, Timothy J.; Pruess, Jacob; Tomutsa, Liviu; Reiter, Paul A.; deCastro, Ted M.
2006-07-25
An operator shielded X-ray imaging system has sufficiently low mass (less than 300 kg) and is compact enough to enable portability by reducing operator shielding requirements to a minimum shielded volume. The resultant shielded volume may require a relatively small mass of shielding in addition to the already integrally shielded X-ray source, intensifier, and detector. The system is suitable for portable imaging of well cores at remotely located well drilling sites. The system accommodates either small samples, or small cross-sectioned objects of unlimited length. By rotating samples relative to the imaging device, the information required for computer aided tomographic reconstruction may be obtained. By further translating the samples relative to the imaging system, fully three dimensional (3D) tomographic reconstructions may be obtained of samples having arbitrary length.
NASA Astrophysics Data System (ADS)
Shang, Yanliang; Shi, Wenjun; Han, Tongyin; Qin, Zhichao; Du, Shouji
2017-10-01
The shield method has many advantages in the construction of urban subway, and has become the preferred method for the construction of urban subway tunnel. Taking Shijiazhuang metro line 3 (administrative center station - garden park station interval) Passing alongside bridge as the engineering background, double shield crossing the bridge pile foundation model was set up. The deformation and internal force of the pile foundation during the construction of the shield were analyzed. Pile stress caused by shield construction increases, but the maximum stress is less than the design strength; the maximum surface settlement caused by the construction of 10.2 mm, the results meet the requirements of construction.
Griffin, M; Panak, W F
1998-07-01
To examine the costs and outcomes of infertility-related services in Massachusetts during a time of expanded use of assisted reproductive technology (ART). Cost data were obtained from the Massachusetts Department of Insurance Rate-Setting Commission and 9 large group insurance plans for the period 1986-1993. Utilization and success rates of ART were examined, and the cost per live delivery with the use of ART in 1993 was estimated. The state of Massachusetts, in which access to infertility-related services has been mandated by law since 1989. The study population consisted of 8 large health maintenance organization plans and the Blue Cross/Blue Shield indemnity plan. None. Per capita infertility-related expenditures, infertility-related expenditures as a percentage of total expenditures, live deliveries per initiated ART cycle, and cost per live delivery. Expenditures for infertility services increased at a rate similar to or slower than inflation during the years 1988-1992. Increases were slowest in health maintenance organizations, probably as a result of provider arrangements. Infertility services accounted for 0.41% of total expenditures within the indemnity plan in 1993 (approximately $1.71 per contract-month). Examination of ART utilization showed no evidence of overutilization by patients with a low chance of success. The cost per live delivery with the use of ART in 1993 was $59,484. Mandated infertility coverage was associated with increased use of ART but not with excessive increases in consumer cost for infertility insurance coverage.
Reducing medical service utilization by encouraging vaccines: randomized controlled trial.
Berg, Gregory D; Thomas, Eileen; Silverstein, Steven; Neel, Cheryl L; Mireles, Matthew
2004-11-01
Vaccination against influenza is associated with reductions in hospitalizations for heart disease, cerebrovascular disease, pneumonia, or influenza, and the risk of death from all causes during the influenza season. Randomized controlled trial. All members enrolled in the Blue Cross Blue Shield Association's Government Wide Service Benefit Program in the states of Oklahoma, Rhode Island, Kentucky, California, Arizona, Utah, and Colorado in October 2002. The sample size was 339,220 members. Two identical influenza/pneumonia direct mail marketing pieces that encouraged members to receive influenza and pneumococcal vaccinations. The study period was October 15, 2002 through March 15, 2003 when most influenza cases occur. Data were collected in July 2003 and analyzed during August 2003. Administrative claims based on influenza/pneumonia inpatient admissions and emergency department (ED) visits. The intervention group experienced a 2.62% (p=0.010) higher rate of influenza vaccinations; 4.61% (p=0.080) higher rate of pneumonia vaccinations; 9.67% (p=0.136) lower rate of influenza/pneumonia inpatient admissions; and 22.64% (p=0.002) lower rate of influenza/pneumonia ED visits compared to the control group. The benefit-cost ratio (return on investment) from this intervention was estimated to be US dollar 2.21 per dollar spent. Administrative claims data suggest that members respond to health plan mailings with an increase in influenza vaccination rates. Health plans can cost-effectively impact medical service utilization and vaccination rates by mailing information to their members.
vanVonno, Catherine J; Ozminkowski, Ronald J; Smith, Mark W; Thomas, Eileen G; Kelley, Doniece; Goetzel, Ron; Berg, Gregory D; Jain, Susheel K; Walker, David R
2005-12-01
In 1999, the Blue Cross and Blue Shield Federal Employee Program (FEP) implemented a pilot disease management program to manage congestive heart failure (CHF) among members. The purpose of this project was to estimate the financial return on investment in the pilot CHF program, prior to a full program rollout. A cohort of 457 participants from the state of Maryland was matched to a cohort of 803 nonparticipants from a neighboring state where the CHF program was not offered. Each cohort was followed for 12 months before the program began and 12 months afterward. The outcome measures of primary interest were the differences over time in medical care expenditures paid by FEP and by all payers. Independent variables included indicators of program participation, type of heart disease, comorbidity measures, and demographics. From the perspective of the funding organization (FEP), the estimated return on investment for the pilot CHF disease management program was a savings of $1.08 in medical expenditure for every dollar spent on the program. Adding savings to other payers as well, the return on investment was a savings of $1.15 in medical expenditures per dollar spent on the program. The amount of savings depended upon CHF risk levels. The value of a pilot initiative and evaluation is that lessons for larger-scale efforts can be learned prior to full-scale rollout.
Evaluation of Shielding Performance for Newly Developed Composite Materials
NASA Astrophysics Data System (ADS)
Evans, Beren Richard
This work details an investigation into the contributing factors behind the success of newly developed composite neutron shield materials. Monte Carlo simulation methods were utilized to assess the neutron shielding capabilities and secondary radiation production characteristics of aluminum boron carbide, tungsten boron carbide, bismuth borosilicate glass, and Metathene within various neutron energy spectra. Shielding performance and secondary radiation data suggested that tungsten boron carbide was the most effective composite material. An analysis of the macroscopic cross-section contributions from constituent materials and interaction mechanisms was then performed in an attempt to determine the reasons for tungsten boron carbide's success over the other investigated materials. This analysis determined that there was a positive correlation between a non-elastic interaction contribution towards a material's total cross-section and shielding performance within the thermal and epi-thermal energy regimes. This finding was assumed to be a result of the boron-10 absorption reaction. The analysis also determined that within the faster energy regions, materials featuring higher non-elastic interaction contributions were comparable to those exhibiting primarily elastic scattering via low Z elements. This allowed for the conclusion that composite shield success within higher energy neutron spectra does not necessitate the use elastic scattering via low Z elements. These findings suggest that the inclusion of materials featuring high thermal absorption properties is more critical to composite neutron shield performance than the presence of constituent materials more inclined to maximize elastic scattering energy loss.
Özyürek, Taha; Gündoğar, Mustafa; Yılmaz, Koray; Uslu, Gülşah
2017-01-01
Background. This study compared the cyclic fatigue resistance, bending resistance and cross-sectional areas of Reciproc Blue (RPC Blue), WaveOne Gold (WOG), and Genius File (GF) NiTi rotary systems. Methods. Forty RPC Blue R25 (25/.08), 40 WOG Primary (25/.07) and 40 GF (25/.04) files were used in the present study. Flexibility of the files was determined by 45° bending test. The instruments were also subjected to cyclic fatigue resistance, calculating the number of cycles to fracture (NCF) in an S-shaped artificial stainless steel canal. Also the cross-sectional areas of the files were measured at D5 level. The length of the fractured file tips was measured. The fracture surface of all the fragments was examined with a scanning electron microscope. Data was statistically analyzed using one-way ANOVA and post hoc Tukey tests. Results. In both the apical and coronal curvatures, the NCF of the GF was significantly higher than that of the RPC Blue and WOG files. There was no significant difference between the GF, WOG and Reciproc Blue files with respect to the lengths of the fractured file fragments in either the apical or coronal curvature. The bending resistance of the GF was signif-icantly higher than that of the RPC Blue and WOG files. The RPC Blue had the largest cross-sectional area, and the GF had the smallest cross-sectional area. Conclusion. Within the limitations of the present study, the GF NiTi system exhibited the highest cyclic and bending re-sistance among the experimental groups.
NASA Astrophysics Data System (ADS)
DiJulio, D. D.; Cooper-Jensen, C. P.; Llamas-Jansa, I.; Kazi, S.; Bentley, P. M.
2018-06-01
A combined measurement and Monte-Carlo simulation study was carried out in order to characterize the particle self-shielding effect of B4C grains in neutron shielding concrete. Several batches of a specialized neutron shielding concrete, with varying B4C grain sizes, were exposed to a 2 Å neutron beam at the R2D2 test beamline at the Institute for Energy Technology located in Kjeller, Norway. The direct and scattered neutrons were detected with a neutron detector placed behind the concrete blocks and the results were compared to Geant4 simulations. The particle self-shielding effect was included in the Geant4 simulations by calculating effective neutron cross-sections during the Monte-Carlo simulation process. It is shown that this method well reproduces the measured results. Our results show that shielding calculations for low-energy neutrons using such materials would lead to an underestimate of the shielding required for a certain design scenario if the particle self-shielding effect is not included in the calculations.
Hull, D.E.
1982-07-02
An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.
Hull, Donald E.
1984-01-01
An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.
McSKY: A hybrid Monte-Carlo lime-beam code for shielded gamma skyshine calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shultis, J.K.; Faw, R.E.; Stedry, M.H.
1994-07-01
McSKY evaluates skyshine dose from an isotropic, monoenergetic, point photon source collimated into either a vertical cone or a vertical structure with an N-sided polygon cross section. The code assumes an overhead shield of two materials, through the user can specify zero shield thickness for an unshielded calculation. The code uses a Monte-Carlo algorithm to evaluate transport through source shields and the integral line source to describe photon transport through the atmosphere. The source energy must be between 0.02 and 100 MeV. For heavily shielded sources with energies above 20 MeV, McSKY results must be used cautiously, especially at detectormore » locations near the source.« less
Impact of cross-field motion on ablation of high-Z dust in fusion edge plasmas
Smirnov, R. D.; Krasheninnikov, S. I.
2017-07-05
The impact of cross-field motion of high-Z dust grains on their shielding by ablation cloud in edge plasmas of tokamaks is analyzed. The modification of the existing high-Z dust shielding theory is developed, which takes the dust motion effects into account. We show that the cross-field motion can lead to a large factor increase of the dust ablation rate, as compared to the previous model. It is also shown that the motion effects take place when the dust cross-field velocity exceeds a threshold value. We also obtain the dependencies of the dust ablation flux on the dust velocity and ofmore » the threshold velocity on the dust size and the ambient plasma temperature.« less
Impact of cross-field motion on ablation of high-Z dust in fusion edge plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smirnov, R. D.; Krasheninnikov, S. I.
The impact of cross-field motion of high-Z dust grains on their shielding by ablation cloud in edge plasmas of tokamaks is analyzed. The modification of the existing high-Z dust shielding theory is developed, which takes the dust motion effects into account. We show that the cross-field motion can lead to a large factor increase of the dust ablation rate, as compared to the previous model. It is also shown that the motion effects take place when the dust cross-field velocity exceeds a threshold value. We also obtain the dependencies of the dust ablation flux on the dust velocity and ofmore » the threshold velocity on the dust size and the ambient plasma temperature.« less
The Effects of Premium Changes on ALL Kids, Alabama's CHIP Program
Morrisey, Michael A.; Blackburn, Justin; Sen, Bisakha; Becker, David; Kilgore, Meredith L.; Caldwell, Cathy; Menachemi, Nir
2012-01-01
Objective Describe the trends in enrollment and renewal in the Alabama Children's Health Insurance Plan (CHIP), ALL Kids, since its creation in 1998, and to estimate the effect that an annual premium increase, along with coincident increases in service copays, had on the decision to renew participation. Background: Unlike many other CHIP programs, ALL Kids is a standalone program that provides year long enrollment and contracts with the state's Blue Cross and Blue Shield program for its network of providers and its provider fee structure. In October 2003 premiums for individual coverage were increased by $50 per year and copays by $1 to $3 per visit. Population Studied This study is based upon a sample of 569,650 person-year observations of 230,255 children enrolled in the ALL Kids program between 1999 and 2009. Study Design The study models enrollment as a time series of cross section renewal decisions and specifies a series of linear probability regression models to estimate the effect of changes in the premium shift on the decision to renew. A second analysis includes interaction effects of the premiums shift with demographics, health status, income and previous enrollment to estimate differential response across subgroups. Principal Findings The increases in premiums and copays are estimated to have reduced program renewals by 6.1 to 8.3 percent depending upon how much time one allows for families to renew. Families with a child who has a chronic condition were more likely to renew coverage. However, those with chronic conditions, African-Americans and those with lower family incomes were more price-sensitive. Conclusions An increase in annual premiums and visit copays had a modest impact on program reenrollment with effects comparable to those found in Florida, New Hampshire, Kansas and Arizona, but smaller than those in Kentucky and Georgia. PMID:24800149
Active Proton Interrogation for Homeland Security
NASA Astrophysics Data System (ADS)
Greene, Steven; Morris, Christopher; Canavan, Gregory; Chung, Kiwhan; Elson, Jay; Hogan, Gary; Makela, Mark; Mariam, Fesseha; Murray, Matthew; Saunders, Alexander; Spaulding, Randy; Wang, Zhehui; Waters, Laurie; Wysocki, Frederick
2010-02-01
Energetic proton beams may provide an attractive technology for active interrogation of nuclear threats because: they have large fission cross sections, long mean free paths and high penetration, and proton beams can be manipulated with magnetic optics. We have measured time-dependent cross sections for delayed neutrons and gamma rays using 800 MeV protons from the Los Alamos Neutron Science Center and 4 GeV protons from the Brookhaven Alternating Gradient Synchrotron for a set of bare and shielded targets. The results show significant signals from both unshielded and shielded nuclear materials. Results will be presented. )
NASA Astrophysics Data System (ADS)
Pescarini, Massimo; Sinitsa, Valentin; Orsi, Roberto; Frisoni, Manuela
2016-02-01
Two broad-group coupled neutron/photon working cross section libraries in FIDO-ANISN format, dedicated to LWR shielding and pressure vessel dosimetry applications, were generated following the methodology recommended by the US ANSI/ANS-6.1.2-1999 (R2009) standard. These libraries, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, are respectively based on JEFF-3.1.1 and ENDF/B-VII.0 nuclear data and adopt the same broad-group energy structure (47 n + 20 γ) of the ORNL BUGLE-96 similar library. They were respectively obtained from the ENEA-Bologna VITJEFF311.BOLIB and VITENDF70.BOLIB libraries in AMPX format for nuclear fission applications through problem-dependent cross section collapsing with the ENEA-Bologna 2007 revision of the ORNL SCAMPI nuclear data processing system. Both previous libraries are based on the Bondarenko self-shielding factor method and have the same AMPX format and fine-group energy structure (199 n + 42 γ) as the ORNL VITAMIN-B6 similar library from which BUGLE-96 was obtained at ORNL. A synthesis of a preliminary validation of the cited BUGLE-type libraries, performed through 3D fixed source transport calculations with the ORNL TORT-3.2 SN code, is included. The calculations were dedicated to the PCA-Replica 12/13 and VENUS-3 engineering neutron shielding benchmark experiments, specifically conceived to test the accuracy of nuclear data and transport codes in LWR shielding and radiation damage analyses.
Calculation of self–shielding factor for neutron activation experiments using GEANT4 and MCNP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Romero–Barrientos, Jaime, E-mail: jaromero@ing.uchile.cl; Universidad de Chile, DFI, Facultad de Ciencias Físicas Y Matemáticas, Avenida Blanco Encalada 2008, Santiago; Molina, F.
2016-07-07
The neutron self–shielding factor G as a function of the neutron energy was obtained for 14 pure metallic samples in 1000 isolethargic energy bins from 1·10{sup −5}eV to 2·10{sup 7}eV using Monte Carlo simulations in GEANT4 and MCNP6. The comparison of these two Monte Carlo codes shows small differences in the final self–shielding factor mostly due to the different cross section databases that each program uses.
Blue Pattern Flower in Common Bean Expressed by Interaction of Prpi-2 with a New Gene tbp
USDA-ARS?s Scientific Manuscript database
The inheritance of blue pattern flower (BPF) expression was investigated in common bean (Phaseolus vulgaris L.). The BPF trait was derived from accession line G07262, and the flowers express blue banner petal and white wings with blue veins. Crosses between a BPF stock and three other parents - t ...
Structural Monitoring of Metro Infrastructure during Shield Tunneling Construction
Ran, L.; Ye, X. W.; Ming, G.; Dong, X. B.
2014-01-01
Shield tunneling construction of metro infrastructure will continuously disturb the soils. The ground surface will be subjected to uplift or subsidence due to the deep excavation and the extrusion and consolidation of the soils. Implementation of the simultaneous monitoring with the shield tunnel construction will provide an effective reference in controlling the shield driving, while how to design and implement a safe, economic, and effective structural monitoring system for metro infrastructure is of great importance and necessity. This paper presents the general architecture of the shield construction of metro tunnels as well as the procedure of the artificial ground freezing construction of the metro-tunnel cross-passages. The design principles for metro infrastructure monitoring of the shield tunnel intervals in the Hangzhou Metro Line 1 are introduced. The detailed monitoring items and the specified alarming indices for construction monitoring of the shield tunneling are addressed, and the measured settlement variations at different monitoring locations are also presented. PMID:25032238
Preliminary analyses of space radiation protection for lunar base surface systems
NASA Technical Reports Server (NTRS)
Nealy, John E.; Wilson, John W.; Townsend, Lawrence W.
1989-01-01
Radiation shielding analyses are performed for candidate lunar base habitation modules. The study primarily addresses potential hazards due to contributions from the galactic cosmic rays. The NASA Langley Research Center's high energy nucleon and heavy ion transport codes are used to compute propagation of radiation through conventional and regolith shield materials. Computed values of linear energy transfer are converted to biological dose-equivalent using quality factors established by the International Commision of Radiological Protection. Special fluxes of heavy charged particles and corresponding dosimetric quantities are computed for a series of thicknesses in various shield media and are used as an input data base for algorithms pertaining to specific shielded geometries. Dosimetric results are presented as isodose contour maps of shielded configuration interiors. The dose predictions indicate that shielding requirements are substantial, and an abbreviated uncertainty analysis shows that better definition of the space radiation environment as well as improvement in nuclear interaction cross-section data can greatly increase the accuracy of shield requirement predictions.
NASA Technical Reports Server (NTRS)
Lahti, G. P.; Mueller, R. A.
1973-01-01
Measurements of MeV neutron were made at the surface of a lithium hydride and depleted uranium shielded reactor. Four shield configurations were considered: these were assembled progressively with cylindrical shells of 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, and 3-centimeter-thick depleted uranium. Measurements were made with a NE-218 scintillation spectrometer; proton pulse height distributions were differentiated to obtain neutron spectra. Calculations were made using the two-dimensional discrete ordinates code DOT and ENDF/B (version 3) cross sections. Good agreement between measured and calculated spectral shape was observed. Absolute measured and calculated fluxes were within 50 percent of one another; observed discrepancies in absolute flux may be due to cross section errors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Richard Dean; Thom, Robert Anthony
A light shielding apparatus for blocking light from reaching an electronic device, the light shielding apparatus including left and right support assemblies, a cross member, and an opaque shroud. The support assemblies each include primary support structure, a mounting element for removably connecting the apparatus to the electronic device, and a support member depending from the primary support structure for retaining the apparatus in an upright orientation. The cross member couples the left and right support assemblies together and spaces them apart according to the size and shape of the electronic device. The shroud may be removably and adjustably connectablemore » to the left and right support assemblies and configured to take a cylindrical dome shape so as to form a central space covered from above. The opaque shroud prevents light from entering the central space and contacting sensitive elements of the electronic device.« less
Importance of resonance interference effects in multigroup self-shielding calculation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stachowski, R.E.; Protsik, R.
1995-12-31
The impact of the resonance interference method (RIF) on multigroup neutron cross sections is significant for major isotopes in the fuel, indicating the importance of resonance interference in the computation of gadolinia burnout and plutonium buildup. The self-shielding factor method with the RIF method effectively eliminates shortcomings in multigroup resonance calculations.
Mertins, Omar; Mathews, Patrick D; Gomide, Andreza B; Baptista, Mauricio S; Itri, Rosangela
2015-10-01
We have prepared a chitosan polymer modified with gallic acid in order to develop an efficient protection strategy biological membranes against photodamage. Lipid bilayers were challenged with photoinduced damage by photosensitization with methylene blue, which usually causes formation of hydroperoxides, increasing area per lipid, and afterwards allowing leakage of internal materials. The damage was delayed by a solution of gallic acid in a concentration dependent manner, but further suppressed by the polymer at very low concentrations. The membrane of giant unilamellar vesicles was covered with this modified macromolecule leading to a powerful shield against singlet oxygen and thus effectively protecting the lipid membrane from oxidative stress. The results have proven the discovery of a promising strategy for photo protection of biological membranes. Copyright © 2015 Elsevier B.V. All rights reserved.
Gurm, Hitinder S; Smith, Dean E; Berwanger, Otavio; Share, David; Schreiber, Theodore; Moscucci, Mauro; Nallamothu, Brahmajee K
2012-01-01
The aim of this study was to examine the use of and outcomes associated with use of N-acetylcysteine (NAC) in real-world practice. The role of NAC in the prevention of contrast-induced nephropathy (CIN) is controversial, leading to widely varying recommendations for its use. Use of NAC was assessed in consecutive patients undergoing nonemergent percutaneous coronary intervention from 2006 to 2009 in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium, a large multicenter quality improvement collaborative. We examined the overall prevalence of NAC use in these patients and then used propensity matching to link its use with clinical outcomes, including CIN, nephropathy-requiring dialysis, and death. Of the 90,578 percutaneous coronary interventions performed during the study period, NAC was used in 10,574 (11.6%) procedures, with its use steadily increasing over the study period. Patients treated with NAC were slightly older and more likely to have baseline renal insufficiency and other comorbidities. In propensity-matched, risk-adjusted models, we found no differences in outcomes between patients treated with NAC and those not receiving NAC for CIN (5.5% vs. 5.5%, p = 0.99), nephropathy-requiring dialysis (0.6% vs. 0.6%, p = 0.69), or death (0.6% vs. 0.8%, p = 0.15). These findings were consistent across many prespecified subgroups. Use of NAC is common and has steadily increased over the study period but does not seem to be associated with improved clinical outcomes in real-world practice. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Global Budgets and Technology-Intensive Medical Services.
Song, Zirui; Fendrick, A Mark; Safran, Dana Gelb; Landon, Bruce; Chernew, Michael E
2013-06-01
In 2009-2010, Blue Cross Blue Shield of Massachusetts entered into global payment contracts (the Alternative Quality contract, AQC) with 11 provider organizations. We evaluated the impact of the AQC on spending and utilization of several categories of medical technologies, including one considered high value (colonoscopies) and three that include services that may be overused in some situations (cardiovascular, imaging, and orthopedic services). Approximately 420,000 unique enrollees in 2009 and 180,000 in 2010 were linked to primary care physicians whose organizations joined the AQC. Using three years of pre-intervention data and a large control group, we analyzed changes in utilization and spending associated with the AQC with a propensity-weighted difference-in-differences approach adjusting for enrollee demographics, health status, secular trends, and cost-sharing. In the 2009 AQC cohort, total volume of colonoscopies increased 5.2 percent (p=0.04) in the first two years of the contract relative to control. The contract was associated with varied changes in volume for cardiovascular and imaging services, but total spending on cardiovascular services in the first two years decreased by 7.4% (p=0.02) while total spending on imaging services decreased by 6.1% (p<0.001) relative to control. In addition to lower utilization of higher-priced services, these decreases were also attributable to shifting care to lower-priced providers. No effect was found in orthopedics. As one example of a large-scale global payment initiative, the AQC was associated with higher use of colonoscopies. Among several categories of services whose value may be controversial, the contract generally shifted volume to lower-priced facilities or services.
Roles of prices, poverty, and health in Medicare and private spending in Texas.
White, Chapin; Taychakhoonavudh, Suthira; Parikh, Rohan; Franzini, Luisa
2015-05-01
To investigate the roles of prices, poverty, and health in divergences between Medicare and private spending in Texas. Retrospective observational design using 2011 Blue Cross Blue Shield of Texas claims data and publicly available Medicare data. We measured market-level spending per enrollee among the privately insured. Variation in Medicare and private spending per person are decomposed into prices and quantities, and their associations with poverty are measured. Markets are divided into 4 groups and are compared based on the ratio of Medicare to private spending: "high-private," "proportional," "high-Medicare," and "extremely high-Medicare." Among the privately insured, poverty appears to have large spillover effects; it is strongly associated with lower prices, quantities, and spending. Among Medicare beneficiaries, health status is a key driver of spending variation. The 2 markets with extremely high Medicare-to-private spending ratios (Harlingen and McAllen) are predominantly Hispanic communities with markedly higher rates of poverty and lack of insurance and also extremely low physician supply. The markets with relatively high private spending stand out for having good health-system performance and health outcomes, and higher than average hospital prices. Variation in private spending appears to reflect the ability of the local population to pay for healthcare, whereas variation in Medicare is more heavily driven by health status, and presumably, by clinical need. These findings highlight the inadvisability of using Medicare spending as a proxy for systemwide spending, and the need for comprehensive market-level spending data that allow comparisons among populations with different sources of insurance coverage.
Mathis, Michael R; Naughton, Norah N; Shanks, Amy M; Freundlich, Robert E; Pannucci, Christopher J; Chu, Yijia; Haus, Jason; Morris, Michelle; Kheterpal, Sachin
2013-12-01
Due to economic pressures and improvements in perioperative care, outpatient surgical procedures have become commonplace. However, risk factors for outpatient surgical morbidity and mortality remain unclear. There are no multicenter clinical data guiding patient selection for outpatient surgery. The authors hypothesize that specific risk factors increase the likelihood of day case-eligible surgical morbidity or mortality. The authors analyzed adults undergoing common day case-eligible surgical procedures by using the American College of Surgeons' National Surgical Quality Improvement Program database from 2005 to 2010. Common day case-eligible surgical procedures were identified as the most common outpatient surgical Current Procedural Terminology codes provided by Blue Cross Blue Shield of Michigan and Medicare publications. Study variables included anthropometric data and relevant medical comorbidities. The primary outcome was morbidity or mortality within 72 h. Intraoperative complications included adverse cardiovascular events; postoperative complications included surgical, anesthetic, and medical adverse events. Of 244,397 surgeries studied, 232 (0.1%) experienced early perioperative morbidity or mortality. Seven independent risk factors were identified while controlling for surgical complexity: overweight body mass index, obese body mass index, chronic obstructive pulmonary disease, history of transient ischemic attack/stroke, hypertension, previous cardiac surgical intervention, and prolonged operative time. The demonstrated low rate of perioperative morbidity and mortality confirms the safety of current day case-eligible surgeries. The authors obtained the first prospectively collected data identifying risk factors for morbidity and mortality with day case-eligible surgery. The results of the study provide new data to advance patient-selection processes for outpatient surgery.
SHIELD and HZETRN comparisons of pion production cross sections
NASA Astrophysics Data System (ADS)
Norbury, John W.; Sobolevsky, Nikolai; Werneth, Charles M.
2018-03-01
A program of comparing American (NASA) and Russian (ROSCOSMOS) space radiation transport codes has recently begun, and the first paper directly comparing the NASA and ROSCOSMOS space radiation transport codes, HZETRN and SHIELD respectively has recently appeared. The present work represents the second time that NASA and ROSCOSMOS calculations have been directly compared, and the focus here is on models of pion production cross sections used in the two transport codes mentioned above. It was found that these models are in overall moderate agreement with each other and with experimental data. Disagreements that were found are discussed.
Resonance treatment using pin-based pointwise energy slowing-down method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Sooyoung, E-mail: csy0321@unist.ac.kr; Lee, Changho, E-mail: clee@anl.gov; Lee, Deokjung, E-mail: deokjung@unist.ac.kr
A new resonance self-shielding method using a pointwise energy solution has been developed to overcome the drawbacks of the equivalence theory. The equivalence theory uses a crude resonance scattering source approximation, and assumes a spatially constant scattering source distribution inside a fuel pellet. These two assumptions cause a significant error, in that they overestimate the multi-group effective cross sections, especially for {sup 238}U. The new resonance self-shielding method solves pointwise energy slowing-down equations with a sub-divided fuel rod. The method adopts a shadowing effect correction factor and fictitious moderator material to model a realistic pointwise energy solution. The slowing-down solutionmore » is used to generate the multi-group cross section. With various light water reactor problems, it was demonstrated that the new resonance self-shielding method significantly improved accuracy in the reactor parameter calculation with no compromise in computation time, compared to the equivalence theory.« less
NASA Astrophysics Data System (ADS)
Sayyed, M. I.; Lakshminarayana, G.; Kityk, I. V.; Mahdi, M. A.
2017-10-01
In this work, we have evaluated the γ-ray shielding parameters such as mass attenuation coefficient (μ/ρ), effective atomic number (Zeff), half value layer (HVL), mean free path (MFP) and exposure buildup factors (EBF) for heavy metal fluoride (PbF2) based tellurite-rich glasses. In addition, neutron total macroscopic cross sections (∑R) for these glasses were also calculated. The maximum value for μ/ρ, Zeff and ∑R was found for heavy metal (Bi2O3) oxide introduced glass. The results of the selected glasses have been compared, in terms of MFP with different glass systems. The shielding effectiveness of the selected glasses is found comparable or better than of common ones, which indicates that these glasses with suitable oxides could be developed for gamma ray shielding applications.
Is sadness blue? The problem of using figurative language for emotions on psychological tests.
Barchard, Kimberly A; Grob, Kelly E; Roe, Matthew J
2017-04-01
Psychological tests sometimes include figurative language like I feel blue. However, figurative language may not mean the same thing cross-culturally. Previous research found cross-cultural evidence for 14 conceptual metaphors and metonymies for emotions (e.g., sadness is blue). Our two studies asked participants (total n = 795) in the USA and India whether happiness, sadness, anger, and fear are associated with certain descriptors (blue, down, bright, etc.). Most participants in both countries endorsed ten of the 14 hypothesized associations; however, the percentage of participants endorsing an association was often far from 100 %. For example, in the USA, only 71.7 % associated hot with anger and only 65.9 % associated blue with sadness. Moreover, descriptors were often associated with more than one emotion. Furthermore, only two associations (happiness is up and bright) were endorsed by more than 90 % of participants in both countries and had descriptors that were not associated with additional emotions. We conclude that figurative language is often ambiguous and should be used with caution on psychological tests unless there is evidence the language is understood cross-culturally. Advice to this effect is currently lacking from psychometrics textbooks and should be added.
Strategic Sealift for Desert Shield not a Blue Print for the Future
1991-06-21
the requirements of the Department of Operations. The contents of this paper reflect our own personal views and are not necessarily endorsed by the...answers without breaching operational security most telephone and personal interviews were held on a non- attributable basis. However, we feel that there...MV is LT Jack Lu:uus. MV !st LT Baldomero Lopez and MV PFC Dwayne T. Williams) commanded by Capt. Charles E. Aaker , USN. also got underway on August
NASA Astrophysics Data System (ADS)
Crabtree, Stephen M.; Huber, Abigail; Beck, Karl
2017-05-01
Blue Rock is a basaltic shield volcano in the southern Oregon Cascades, north of Mt. McLoughlin, showing bulk phenocryst abundances ranging from 5 to 28 vol%, and a variety of groundmass textures. Compositional analyses of olivine and plagioclase phenocrysts and glomerocrysts allowed for the sequential application of a new {D}_{Ni}^{olivine-melt} thermometer, a plagioclase-melt hygrometer, and a viscosity model to define olivine-in conditions for a suite of lavas erupted from this edifice. Calculated olivine-in temperatures were compared to results from the anhydrous MELTS model, and the D (Mg) model of Beattie (1993). Model results were consistent with experimental data for hydrous arc basalts with respect to temperature (1053-1146 °C), dissolved-H2O contents (0.9-2.4 wt% H2O), and viscosity (1.9-2.2 log10 Pa s), confirming the utility of these models in assessing the thermodynamic properties of mafic, hydrous arc lavas over a broad range in crystallinity, requiring only the completion of bulk geochemical and microprobe analyses. These studies also reinforced the significant and predictable role of water, affecting the compositions of crystals grown during magmatic ascent, and allowed the definition of a reasonable multi-stage eruptive sequence consistent with the degassing of magmas on ascent in the formation of this small-scale basaltic edifice.
Formation of negative hydrogen ion: polarization electron capture and nonthermal shielding.
Ki, Dae-Han; Jung, Young-Dae
2012-09-07
The influence of the nonthermal shielding on the formation of the negative hydrogen ion (H(-)) by the polarization electron capture are investigated in partially ionized generalized Lorentzian plasmas. The Bohr-Lindhard method has been applied to obtain the negative hydrogen formation radius and cross section as functions of the collision energy, de Broglie wave length, Debye length, impact parameter, and spectral index of the plasma. The result shows that the nonthermal character of the plasma enhances the formation radius of the negative hydrogen, especially, for small Debye radii. It is found that the nonthermal effect increases the formation cross section of the negative hydrogen. It is also found that the maximum position of the formation cross section approaches to the collision center with an increase of the spectral index. In addition, it is found that the formation cross section significantly decreases with an increase of the Debye length, especially, for small spectral indices.
Shielded helix traveling wave cathode ray tube deflection structure
Norris, Neil J.; Hudson, Charles L.
1992-01-01
Various embodiments of a helical coil deflection structure of a CRT are described and illustrated which provide shielding between adjacent turns of the coil on either three or four sides of each turn in the coil. Threaded members formed with either male or female threads and having the same pitch as the deflection coil are utilized for shielding the deflection coil with each turn of the helical coil placed between adjacent threads which act to shield each coil turn from adjacent turns and to confine the field generated by the coil to prevent or inhibit cross-coupling between adjacent turns of the coil to thereby prevent generation of fast fields which might otherwise deflect the beam out of time synchronization with the electron beam pulse.
Shielding analyses: the rabbit vs the turtle?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broadhead, B.L.
1996-12-31
This paper compares solutions using Monte Carlo and discrete- ordinates methods applied to two actual shielding situations in order to make some general observations concerning the efficiency and advantages/disadvantages of the two approaches. The discrete- ordinates solutions are performed using two-dimensional geometries, while the Monte Carlo approaches utilize three-dimensional geometries with both multigroup and point cross-section data.
Schuldt, Carsten; Karl, Anett; Körber, Nicole; Koch, Christian; Liu, Qing; Fritsch, Anatol W; Reichenbach, Andreas; Wiedemann, Peter; Käs, Josef A; Francke, Mike; Iseli, Hans Peter
2015-08-01
To determine the visco-elastic properties of isolated rabbit scleral tissue and dose-dependent biomechanical and morphological changes after collagen cross-linking by riboflavin/blue light treatment. Scleral patches from 87 adult albino rabbit eyes were examined by dynamic shear rheology. Scleral patches were treated by riboflavin and different intensities of blue light (450 nm), and the impact on the visco-elastic properties was determined by various rheological test regimes. The relative elastic modulus was calculated from non-treated and corresponding treated scleral patches, and treatments with different blue light intensities were compared. Shear rheology enables us to study the material properties of scleral tissue within physiological relevant parameters. Cross-linking treatment increased the viscous as well as the elastic modulus and changed the ratio of the elastic versus viscous proportion in scleral tissue. Constant riboflavin application combined with different blue light intensities from 12 mW/cm(2) up to 100 mW/cm(2) increased the relative elastic modulus of scleral tissue by factors up to 1.8. Further enhancement of the applied light intensity caused a decline of the relative elastic modulus. This might be due to destructive changes of the collagen bundle structure at larger light intensities, as observed by histological examination. Collagen cross-linking by riboflavin/blue light application increases the biomechanical stiffness of the sclera in a dose-dependent manner up to certain light intensities. Therefore, this treatment might be a suitable therapeutic approach to stabilize the biomechanical properties of scleral tissue in cases of pathological eye expansion. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
A New Equivalence Theory Method for Treating Doubly Heterogeneous Fuel - I. Theory
Williams, Mark L.; Lee, Deokjung; Choi, Sooyoung
2015-03-04
A new methodology has been developed to treat resonance self-shielding in doubly heterogeneous very high temperature gas-cooled reactor systems in which the fuel compact region of a reactor lattice consists of small fuel grains dispersed in a graphite matrix. This new method first homogenizes the fuel grain and matrix materials using an analytically derived disadvantage factor from a two-region problem with equivalence theory and intermediate resonance method. This disadvantage factor accounts for spatial self-shielding effects inside each grain within the framework of an infinite array of grains. Then the homogenized fuel compact is self-shielded using a Bondarenko method to accountmore » for interactions between the fuel compact regions in the fuel lattice. In the final form of the equations for actual implementations, the double-heterogeneity effects are accounted for by simply using a modified definition of a background cross section, which includes geometry parameters and cross sections for both the grain and fuel compact regions. With the new method, the doubly heterogeneous resonance self-shielding effect can be treated easily even with legacy codes programmed only for a singly heterogeneous system by simple modifications in the background cross section for resonance integral interpolations. This paper presents a detailed derivation of the new method and a sensitivity study of double-heterogeneity parameters introduced during the derivation. The implementation of the method and verification results for various test cases are presented in the companion paper.« less
Cosmogenic rare gases and 10-Be in a cross section of Knyahinya
NASA Technical Reports Server (NTRS)
Wieler, R.; Signer, P.; Herpers, U.; Sarafin, R.; Bonani, G.; Hofmann, H. J.; Morenzoni, E.; Nessi, M.; Suter, M.; Woelfli, W.
1986-01-01
The concentrations of cosmogenic nuclides were studied as a function of shielding on samples from a cross section of the 293 kg main fragment of the L5 chondrite Knyahinya. The stone broke into two nearly symmetrical parts upon its fall in 1866. The planar cross section has diameters between 40 and 55 cm. He, Ne, and Ar were measured on about 20 samples by mass spectrometry and the 10-Be activities on aliquots of 10 selected samples were determined by AMS. The 10-Be data are presented and the abundances of spallogenic nuclides are compared with the model calculations reported by Reedy for spherical L chondrites. The 10-Be production rates in Knyahinya are shown versus the shielding parameter 22-Ne/21-Ne.
Iseli, Hans Peter; Körber, Nicole; Karl, Anett; Koch, Christian; Schuldt, Carsten; Penk, Anja; Liu, Qing; Huster, Daniel; Käs, Josef; Reichenbach, Andreas; Wiedemann, Peter; Francke, Mike
2015-10-01
Several scleral cross-linking (SXL) methods were suggested to increase the biomechanical stiffness of scleral tissue and therefore, to inhibit axial eye elongation in progressive myopia. In addition to scleral cross-linking and biomechanical effects caused by riboflavin and light irradiation such a treatment might induce tissue damage, dependent on the light intensity used. Therefore, we characterized the damage threshold and mechanical stiffening effect in rabbit eyes after application of riboflavin combined with various blue light intensities. Adult pigmented and albino rabbits were treated with riboflavin (0.5 %) and varying blue light (450 ± 50 nm) dosages from 18 to 780 J/cm(2) (15 to 650 mW/cm(2) for 20 min). Scleral, choroidal and retinal tissue alterations were detected by means of light microscopy, electron microscopy and immunohistochemistry. Biomechanical changes were measured by shear rheology. Blue light dosages of 480 J/cm(2) (400 mW/cm(2)) and beyond induced pathological changes in ocular tissues; the damage threshold was defined by the light intensities which induced cellular degeneration and/or massive collagen structure changes. At such high dosages, we observed alterations of the collagen structure in scleral tissue, as well as pigment aggregation, internal hemorrhages, and collapsed blood vessels. Additionally, photoreceptor degenerations associated with microglia activation and macroglia cell reactivity in the retina were detected. These pathological alterations were locally restricted to the treated areas. Pigmentation of rabbit eyes did not change the damage threshold after a treatment with riboflavin and blue light but seems to influence the vulnerability for blue light irradiations. Increased biomechanical stiffness of scleral tissue could be achieved with blue light intensities below the characterized damage threshold. We conclude that riboflavin and blue light application increased the biomechanical stiffness of scleral tissue at blue light energy levels below the damage threshold. Therefore, applied blue light intensities below the characterized damage threshold might define a therapeutic blue light tolerance range. Copyright © 2015 Elsevier Ltd. All rights reserved.
E-Beam Processing of Polymer Matrix Composites for Multifunctional Radiation Shielding
NASA Technical Reports Server (NTRS)
Hou, Tan-Hung; Wilson, John W.; Jensen, Brian J.; Thibeault, Sheila A.; Chang, Chie K.; Kiefer, Richard L.
2005-01-01
Aliphatic polymers were identified as optimum radiation shielding polymeric materials for building multifunctional structural elements for in-space habitats. Conceptual damage tolerant configurations of polyolefins have been proposed, but many manufacturing issues relied on methods and materials which have sub-optimal radiation shielding characteristics (for example, epoxy matrix and adhesives). In the present approach, we shall investigate e-beam processing technologies for inclusion of high-strength aliphatic polymer reinforcement structures into a highly cross-linked polyolefin matrix. This paper reports the baseline thermo-mechanical properties of low density polyethylene and highly crystallized polyethylene.
THE NON-GROUP SUBSCRIBER—A BLUE SHIELD PROBLEM
Heyd, Charles Gordon
1951-01-01
The basis of prepaid voluntary medical insurance is to provide adequate medical service with the most inexpensive premium rate that is actuarially sound. This has been accomplished up to date by group enrollment. However, this does not provide for enrollment of a large number of insurable persons who are not members of groups. Experience with nongroup subscribers to United Medical Service, New York, is discussed and suggestions are made for simple, inexpensive means of enrollment and premium payments. PMID:14848725
MC 2 -3: Multigroup Cross Section Generation Code for Fast Reactor Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Changho; Yang, Won Sik
This paper presents the methods and performance of the MC2 -3 code, which is a multigroup cross-section generation code for fast reactor analysis, developed to improve the resonance self-shielding and spectrum calculation methods of MC2 -2 and to simplify the current multistep schemes generating region-dependent broad-group cross sections. Using the basic neutron data from ENDF/B data files, MC2 -3 solves the consistent P1 multigroup transport equation to determine the fundamental mode spectra for use in generating multigroup neutron cross sections. A homogeneous medium or a heterogeneous slab or cylindrical unit cell problem is solved in ultrafine (2082) or hyperfine (~400more » 000) group levels. In the resolved resonance range, pointwise cross sections are reconstructed with Doppler broadening at specified temperatures. The pointwise cross sections are directly used in the hyperfine group calculation, whereas for the ultrafine group calculation, self-shielded cross sections are prepared by numerical integration of the pointwise cross sections based upon the narrow resonance approximation. For both the hyperfine and ultrafine group calculations, unresolved resonances are self-shielded using the analytic resonance integral method. The ultrafine group calculation can also be performed for a two-dimensional whole-core problem to generate region-dependent broad-group cross sections. Verification tests have been performed using the benchmark problems for various fast critical experiments including Los Alamos National Laboratory critical assemblies; Zero-Power Reactor, Zero-Power Physics Reactor, and Bundesamt für Strahlenschutz experiments; Monju start-up core; and Advanced Burner Test Reactor. Verification and validation results with ENDF/B-VII.0 data indicated that eigenvalues from MC2 -3/DIF3D agreed well with Monte Carlo N-Particle5 MCNP5 or VIM Monte Carlo solutions within 200 pcm and regionwise one-group fluxes were in good agreement with Monte Carlo solutions.« less
Method for reducing measurement errors of a Langmuir probe with a protective RF shield
NASA Astrophysics Data System (ADS)
Riaby, V.; Masherov, P.; Savinov, V.; Yakunin, V.
2018-04-01
Probe measurements were conducted in the middle cross-section of an inductive, low-pressure xenon plasma using a straight cylindrical Langmuir probe with a bare metal shield that protected the probe from radio frequency interference. As a result, reliable radial distributions of the plasma parameters were obtained. Subsequent analyses of these measurements revealed that the electron energy distribution function (EEDF) deviated substantially from the Maxwellian functions and that this deviation depended on the length of the probe shield. To evaluate the shield's influence on the measurement results, in addition to the probe (which was moved radially as its shield length varied in the range of lsh1 = lmax-0), an additional L-shaped probe was inserted at a different location. This probe was moved differently from the first probe and provided confirmational measurements in the common special position where lsh1 = 0 and lsh2 ≠ 0. In this position, the second shield decreased all the plasma parameters. A comparison of the probe datasets identified the principles of the relationships between measurement errors and EEDF distortions caused by the bare probe shields. This dependence was used to correct the measurements performed using the first probe by eliminating the influence of its shield. Physical analyses based on earlier studies showed that these peculiarities are caused by a short-circuited double-probe effect that occurs in bare metal probe protective shields.
Shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses using WinXCom and MCNP5 code
NASA Astrophysics Data System (ADS)
Dong, M. G.; El-Mallawany, R.; Sayyed, M. I.; Tekin, H. O.
2017-12-01
Gamma ray shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses, where AnOm is Nb2O5 = 0.01, 5, Nd2O3 = 3, 5 and Er2O3 = 5 mol% have been achieved. Shielding parameters; mass attenuation coefficients, half value layers, and macroscopic effective removal cross section for fast neutrons have been computed by using WinXCom program and MCNP5 Monte Carlo code. In addition, by using Geometric Progression method (G-P), exposure buildup factor values were also calculated. Variations of shielding parameters are discussed for the effect of REO addition into the glasses and photon energy.
Shielded helix traveling wave cathode ray tube deflection structure
Norris, N.J.; Hudson, C.L.
1992-12-15
Various embodiments of a helical coil deflection structure of a CRT are described and illustrated which provide shielding between adjacent turns of the coil on either three or four sides of each turn in the coil. Threaded members formed with either male or female threads and having the same pitch as the deflection coil are utilized for shielding the deflection coil with each turn of the helical coil placed between adjacent threads which act to shield each coil turn from adjacent turns and to confine the field generated by the coil to prevent or inhibit cross-coupling between adjacent turns of the coil to thereby prevent generation of fast fields which might otherwise deflect the beam out of time synchronization with the electron beam pulse. 13 figs.
NASA Astrophysics Data System (ADS)
Lee, Myoung-Jae; Jung, Young-Dae
2017-01-01
The quantum shielding effects on the nuclear fusion reaction process are investigated in quantum plasmas. The closed expression of the classical turning point for the Gamow penetration factor in quantum plasmas is obtained by the Lambert W-function. The closed expressions of the Gamow penetration factor and the cross section for the nuclear fusion reaction in quantum plasmas are obtained as functions of the plasmon energy and the relative kinetic energy by using the effective interaction potential with the WKB analysis. It is shown that the influence of quantum screening suppresses the Sommerfeld reaction factor. It is also shown that the Gamow penetration factor increases with an increase of the plasmon energy. It is also shown that the quantum shielding effect enhances the deuterium formation by the proton-proton reaction in quantum plasmas. In addition, it is found that the energy dependences on the reaction cross section and the Gamow penetration factor are more significant in high plasmon-energy domains.
Weiner, Jonathan P; Goodwin, Suzanne M; Chang, Hsien-Yen; Bolen, Shari D; Richards, Thomas M; Johns, Roger A; Momin, Soyal R; Clark, Jeanne M
2013-06-01
Bariatric surgery is a well-documented treatment for obesity, but there are uncertainties about the degree to which such surgery is associated with health care cost reductions that are sustained over time. To provide a comprehensive, multiyear analysis of health care costs by type of procedure within a large cohort of privately insured persons who underwent bariatric surgery compared with a matched nonsurgical cohort. Longitudinal analysis of 2002-2008 claims data comparing a bariatric surgery cohort with a matched nonsurgical cohort. Seven BlueCross BlueShield health insurance plans with a total enrollment of more than 18 million persons. A total of 29 820 plan members who underwent bariatric surgery between January 1, 2002, and December 31, 2008, and a 1:1 matched comparison group of persons not undergoing surgery but with diagnoses closely associated with obesity. Standardized costs (overall and by type of care) and adjusted ratios of the surgical group's costs relative to those of the comparison group. Total costs were greater in the bariatric surgery group during the second and third years following surgery but were similar in the later years. However, the bariatric group's prescription and office visit costs were lower and their inpatient costs were higher. Those undergoing laparoscopic surgery had lower costs in the first few years after surgery, but these differences did not persist. Bariatric surgery does not reduce overall health care costs in the long term. Also, there is no evidence that any one type of surgery is more likely to reduce long-term health care costs. To assess the value of bariatric surgery, future studies should focus on the potential benefit of improved health and well-being of persons undergoing the procedure rather than on cost savings.
Liability claims and costs before and after implementation of a medical error disclosure program.
Kachalia, Allen; Kaufman, Samuel R; Boothman, Richard; Anderson, Susan; Welch, Kathleen; Saint, Sanjay; Rogers, Mary A M
2010-08-17
Since 2001, the University of Michigan Health System (UMHS) has fully disclosed and offered compensation to patients for medical errors. To compare liability claims and costs before and after implementation of the UMHS disclosure-with-offer program. Retrospective before-after analysis from 1995 to 2007. Public academic medical center and health system. Inpatients and outpatients involved in claims made to UMHS. Number of new claims for compensation, number of claims compensated, time to claim resolution, and claims-related costs. After full implementation of a disclosure-with-offer program, the average monthly rate of new claims decreased from 7.03 to 4.52 per 100,000 patient encounters (rate ratio [RR], 0.64 [95% CI, 0.44 to 0.95]). The average monthly rate of lawsuits decreased from 2.13 to 0.75 per 100,000 patient encounters (RR, 0.35 [CI, 0.22 to 0.58]). Median time from claim reporting to resolution decreased from 1.36 to 0.95 years. Average monthly cost rates decreased for total liability (RR, 0.41 [CI, 0.26 to 0.66]), patient compensation (RR, 0.41 [CI, 0.26 to 0.67]), and non-compensation-related legal costs (RR, 0.39 [CI, 0.22 to 0.67]). The study design cannot establish causality. Malpractice claims generally declined in Michigan during the latter part of the study period. The findings might not apply to other health systems, given that UMHS has a closed staff model covered by a captive insurance company and often assumes legal responsibility. The UMHS implemented a program of full disclosure of medical errors with offers of compensation without increasing its total claims and liability costs. Blue Cross Blue Shield of Michigan Foundation.
Hurwitz, Eric L; Li, Dongmei; Guillen, Jenni; Schneider, Michael J; Stevans, Joel M; Phillips, Reed B; Phelan, Shawn P; Lewis, Eugene A; Armstrong, Richard C; Vassilaki, Maria
2016-05-01
The purpose of the study was to compare utilization and charges generated by medical doctors (MD), doctors of chiropractic (DC) and physical therapists (PT) by provider patterns of care for the treatment of neck pain in North Carolina. This was an analysis of neck-pain-related closed claim data from the North Carolina State Health Plan for Teachers and State Employees (NCSHP) from 2000 to 2009. Data were extracted from Blue Cross Blue Shield of North Carolina for the NCSHP using ICD-9 diagnostic codes for uncomplicated neck pain (UNP) and complicated neck pain (CNP). Care patterns with single-provider types and no referrals incurred the least average charges for both UNP and CNP. When care did not include referral providers or services, for either UNP or CNP, MD care with PT was generally less expensive than MD care with DC care. However, when care involved referral providers or services, MD and PT care was on average more expensive than MD and DC care for either UNP or CNP. Risk-adjusted charges for patients in the middle quintile of risk (available 2006-2009) were lower for chiropractic patients with or without medical care or referral care to other providers. Chiropractic care alone or DC with MD care incurred appreciably fewer charges for UNP or CNP compared to MD care with or without PT care, when care included referral providers or services. This finding was reversed when care did not include referral providers or services. Risk-adjusted charges for UNP and CNP patients were lower for DC care patterns. Copyright © 2016 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.
Hurwitz, Eric L; Vassilaki, Maria; Li, Dongmei; Schneider, Michael J; Stevans, Joel M; Phillips, Reed B; Phelan, Shawn P; Lewis, Eugene A; Armstrong, Richard C
2016-05-01
The purpose of the study was to compare patterns of utilization and charges generated by medical doctors (MDs), doctors of chiropractic (DCs), and physical therapists (PTs) for the treatment of headache in North Carolina. Retrospective analysis of claims data from the North Carolina State Health Plan for Teachers and State Employees from 2000 to 2009. Data were extracted from Blue Cross Blue Shield of North Carolina for the North Carolina State Health Plan using International Classification of Diseases, Ninth Revision, diagnostic codes for headache. The claims were separated by individual provider type, combination of provider types, and referral patterns. The majority of patients and claims were in the MD-only or MD plus referral patterns. Chiropractic patterns represented less than 10% of patients. Care patterns with single-provider types and no referrals incurred the least charges on average for headache. When care did not include referral providers or services, MD with DC care was generally less expensive than MD care with PT. However, when combined with referral care, MD care with PT was generally less expensive. Compared with MD-only care, risk-adjusted charges (available 2006-2009) for patients in the middle risk quintile were significantly less for DC-only care. Utilization and expenditures for headache treatment increased from 2000 to 2009 across all provider groups. MD care represented the majority of total allowed charges in this study. MD care and DC care, alone or in combination, were overall the least expensive patterns of headache care. Risk-adjusted charges were significantly less for DC-only care. Copyright © 2016 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.
Hurwitz, Eric L; Li, Dongmei; Guillen, Jenni; Schneider, Michael J; Stevans, Joel M; Phillips, Reed B; Phelan, Shawn P; Lewis, Eugene A; Armstrong, Richard C; Vassilaki, Maria
2016-05-01
The purpose of the study was to compare utilization and charges generated by medical doctors (MD), doctors of chiropractic (DC) and physical therapists (PT) by patterns of care for the treatment of low back pain in North Carolina. This was an analysis of low-back-pain-related closed claim data from the North Carolina State Health Plan for Teachers and State Employees from 2000 to 2009. Data were extracted from Blue Cross Blue Shield of North Carolina for the North Carolina State Health Plan using International Classification of Diseases, 9th Revision diagnostic codes for uncomplicated low back pain (ULBP) and complicated low back pain (CLBP). Care patterns with single-provider types and no referrals incurred the least charges on average for both ULBP and CLBP. When care did not include referral providers or services, for ULBP, MD and DC care was on average $465 less than MD and PT care. For CLBP, MD and DC care averaged $965 more than MD and PT care. However, when care involved referral providers or services, MD and DC care was on average $1600 less when compared to MD and PT care for ULBP and $1885 less for CLBP. Risk-adjusted charges (available 2006-2009) for patients in the middle quintile of risk were significantly less for DC care patterns. Chiropractic care alone or DC with MD care incurred appreciably fewer charges for ULBP than MD care with or without PT care. This finding was reversed for CLBP. Adjusted charges for both ULBP and CLBP patients were significantly lower for DC patients. Copyright © 2016 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.
Frey, Catherine A; Farrell, Philip M; Cotton, Quinton D; Lathen, Lorraine S; Marks, Katherine
2014-02-01
National experts are calling for more integrated approaches such as the life course perspective to reduce health disparities and achieve greater health equity. The translation and application of the life course perspective is therefore of great interest to public health planners, policy makers and funders to promote community-wide improvements in maternal and child health. However, few organizations have applied the life course perspective in designing strategic funding initiatives. For over three decades, Wisconsin has observed persistent racial disparities in birth outcomes. This complex public health issue led to the development of the Lifecourse Initiative for Health Families, a regional multi-million dollar funding initiative created and supported by the Wisconsin Partnership Program of the University of Wisconsin School of Medicine and Public Health (Created by the UW SMPH from an endowment following the conversion of Blue Cross Blue Shield United of Wisconsin, the Partnership Program makes investments in research, education, and public health and prevention initiatives that improve health and reduce health disparities in the state.). Over a 2-year period, the program funded four collaboratives to adopt a life course perspective and develop strategic plans for improving African American birth outcomes. The Twelve-point plan to close the black-white gap in birth outcomes provided the framework for the planning process. Despite the conceptual challenges, the life course perspective was embraced by the collaboratives, challenged community assumptions on the root causes of poor birth outcomes and provided a unifying funding construct for organizing and planning complementary individual-level interventions with social and physical environmental change strategies. These integrated and complimentary approaches provide a long-term opportunity to address the persistent racial birth outcome disparity in Wisconsin.
Lewey, Jennifer; Wei, Wenhui; Makanji, Sagar; Chant, Alan; DiGeronimo, Jeff; Nanchanatt, Gina; Jan, Saira; Choudhry, Niteesh K
2017-01-01
Introduction Adherence to and persistence of medications for chronic diseases remains poor and many interventions to improve medication use have only been modestly effective. Targeting interventions to patients who are most likely to benefit should improve their efficiency and clinical impact. This study aims to test the impact of three cost-equivalent pharmacist-led interventions on insulin persistence and glycaemic control among patients with diabetes. Methods and analysis TARGIT-Diabetes (Targeted Adherence Intervention to Reach Glycemic Control with Insulin Therapy for patients with Diabetes) is a randomised controlled trial that will evaluate three different multifaceted pharmacist-outreach strategies for improving long-term insulin use among individuals with diabetes. We will randomise 6000 patients in a large insurer to one of three arms. The arms are designed to deliver an increasingly intensive intervention to a progressively targeted population, identified using predictive analytics. The central component of the intervention in all arms is a tailored telephone consultation with a pharmacist which varies across arms based on the: (A) proportion of patients offered the intervention and (B) intervention intensity, including follow-up frequency and cointerventions such as text reminders and interactions with patients’ providers. The primary outcome is insulin persistence, assessed using pharmacy claims data, and the secondary outcomes are glycaemic control as measured by glycosylated haemoglobin values, healthcare utilisation and healthcare spending. Ethics and dissemination This protocol has been approved by the Institutional Review Board of Brigham and Women’s Hospital and the Privacy Board of Horizon Blue Cross Blue Shield of New Jersey. We plan to present the results of this trial at national meetings and in manuscripts submitted to peer-reviewed journals. Trial registration number NCT 02846779. PMID:29084790
Edlin, Mari; Johns, Stephanie
2006-01-01
When congress passed the Health Insurance Portability and Accountability act in 1996, the goal was to create a simpler, more standardized system that would eventually lower health care costs; reduce errors through safe, universally accepted electronic communication of health care transactions; and eliminate paper claims. Ten years later, the jury is still out on whether HIPAA has been worth the time, energy, and financial investment for insurers. That's not to say, however, that HIPAA hasn't generated benefits while also creating new challenges. "Standards made sense," says Tom Fitzpatrick, Horizon Blue Cross Blue Shield of New Jersey's director of enterprise strategic planning, "but no one ever said it would be fast, cheap, or easy. It was challenging to integrate proprietary claims systems and legacy software with the new standards that took effect in October 2003. But that wasn't the end of the story. HIPAA's privacy and security rules and the standard identifiers have meant even more upgrades and improvements and have required payers to spend millions of additional dollars over the past three years on HIPAA compliance." According to a set of quarterly surveys conducted by HIMSS/Phoenix Health Systems, progress has actually been fairly rapid. On the other hand, some things have remained much the same. In 2003, payers cited "understanding/interpreting the legal requirements" as the most difficult aspect of the HIPAA remediation process, followed by "achieving successful integration of new policies and procedures" and "resolving issues with third parties". In 2006, the barriers are similar, with users citing the same top two struggles.
Two-Year Impact of the Alternative Quality Contract on Pediatric Health Care Quality and Spending
Song, Zirui; Chernew, Michael E.; Landon, Bruce E.; McNeil, Barbara J.; Safran, Dana G.; Schuster, Mark A.
2014-01-01
OBJECTIVE: To examine the 2-year effect of Blue Cross Blue Shield of Massachusetts’ global budget arrangement, the Alternative Quality Contract (AQC), on pediatric quality and spending for children with special health care needs (CSHCN) and non-CSHCN. METHODS: Using a difference-in-differences approach, we compared quality and spending trends for 126 975 unique 0- to 21-year-olds receiving care from AQC groups with 415 331 propensity-matched patients receiving care from non-AQC groups; 23% of enrollees were CSHCN. We compared quality and spending pre (2006–2008) and post (2009–2010) AQC implementation, adjusting analyses for age, gender, health risk score, and secular trends. Pediatric outcome measures included 4 preventive and 2 acute care measures tied to pay-for-performance (P4P), 3 asthma and 2 attention-deficit/hyperactivity disorder quality measures not tied to P4P, and average total annual medical spending. RESULTS: During the first 2 years of the AQC, pediatric care quality tied to P4P increased by +1.8% for CSHCN (P < .001) and +1.2% for non-CSHCN (P < .001) for AQC versus non-AQC groups; quality measures not tied to P4P showed no significant changes. Average total annual medical spending was ∼5 times greater for CSHCN than non-CSHCN; there was no significant impact of the AQC on spending trends for children. CONCLUSIONS: During the first 2 years of the contract, the AQC had a small but significant positive effect on pediatric preventive care quality tied to P4P; this effect was greater for CSHCN than non-CSHCN. However, it did not significantly influence (positively or negatively) CSHCN measures not tied to P4P or affect per capita spending for either group. PMID:24366988
Syed, Zeeshan; Moscucci, Mauro; Share, David; Gurm, Hitinder S
2015-01-01
Background Clinical tools to stratify patients for emergency coronary artery bypass graft (ECABG) after percutaneous coronary intervention (PCI) create the opportunity to selectively assign patients undergoing procedures to hospitals with and without onsite surgical facilities for dealing with potential complications while balancing load across providers. The goal of our study was to investigate the feasibility of a computational model directly optimised for cohort-level performance to predict ECABG in PCI patients for this application. Methods Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry data with 69 pre-procedural and angiographic risk variables from 68 022 PCI procedures in 2004–2007 were used to develop a support vector machine (SVM) model for ECABG. The SVM model was optimised for the area under the receiver operating characteristic curve (AUROC) at the level of the training cohort and validated on 42 310 PCI procedures performed in 2008–2009. Results There were 87 cases of ECABG (0.21%) in the validation cohort. The SVM model achieved an AUROC of 0.81 (95% CI 0.76 to 0.86). Patients in the predicted top decile were at a significantly increased risk relative to the remaining patients (OR 9.74, 95% CI 6.39 to 14.85, p<0.001) for ECABG. The SVM model optimised for the AUROC on the training cohort significantly improved discrimination, net reclassification and calibration over logistic regression and traditional SVM classification optimised for univariate performance. Conclusions Computational risk stratification directly optimising cohort-level performance holds the potential of high levels of discrimination for ECABG following PCI. This approach has value in selectively referring PCI patients to hospitals with and without onsite surgery. PMID:26688738
Liu, Yifei; Yang, Mei; Chao, Jingdong; Mulani, Parvez M
2010-08-01
Retail pharmacies provide regular prescription drugs and some specialty prescription drugs, whereas specialty pharmacies focus on distributing specialty prescription drugs, including tumor necrosis factor (TNF) antagonists. It is unknown whether pharmacy type impacts patients' adherence to anti-TNF therapy. The relationship between pharmacy type (specialty vs. retail) and refill adherence to therapy with the TNF antagonist adalimumab was examined. This was a retrospective analysis of dispensing records of patients in the United States who were prescribed a TNF antagonist (adalimumab 40 mg per 0.8-mL injection) during a dispensation period from January 2003 to August 2009. Patients treated with adalimumab were included in the analysis regardless of diagnosis. For each patient, medication refill adherence (MRA) was calculated as total days of supply divided by total number of days evaluated, multiplied by 100. A regression analysis was conducted in which the dependent variable was MRA and the independent variables included pharmacy type (specialty vs. retail pharmacy), reimbursement/payment type, copayment/payment amount per prescription, age, sex, ethnicity, and annual income. Of the 86,079 patients included, 70% obtained the medication from a specialty pharmacy, 92% were members of Blue Cross and Blue Shield plans, 67% were women, and 81% were white. The average MRA was 84, and the average age was 52 years. Significant predictors (P<0.05) of MRA included pharmacy type, reimbursement/payment type, copayment/payment amount per prescription, age, sex, and ethnicity; and pharmacy type was the strongest predictor. When other independent variables were controlled for, MRA was 16% less for patients who used a retail pharmacy vs. patients who used a specialty pharmacy. Patients who used a specialty pharmacy to fulfill prescriptions for a TNF antagonist had a greater refill adherence than did patients who used a retail pharmacy.
Impact of alternative interventions on changes in generic dispensing rates.
O'Malley, A James; Frank, Richard G; Kaddis, Atheer; Rothenberg, Barbara M; McNeil, Barbara J
2006-10-01
To evaluate the effectiveness of four alternative interventions (member mailings, advertising campaigns, free generic drug samples to physicians, and physician financial incentives) used by a major health insurer to encourage its members to switch to generic drugs. Using claim-level data from Blue Cross Blue Shield of Michigan, we evaluated the success of four interventions implemented during 2000-2003 designed to increase the use of generic drugs among its members. Around 13 million claims involving seven important classes of drugs were used to assess the effectiveness of the interventions. For each intervention a control group was developed that most closely resembled the corresponding intervention group. Logistic regression models with interaction effects between the treatment group (intervention versus control) and the status of the intervention (active versus not active) were used to evaluate if the interventions had an effect on the generic dispensing rate (GDR). Because the mail order pharmacy was considered more aggressive at converting prescriptions to generics, separate generic purchasing models were fitted to retail and mail order claims. In secondary analyses separate models were also fitted to claims involving a new condition and claims refilled for preexisting conditions. The interventions did not appear to increase the market penetration of generic drugs for either retail or mail order claims, or for claims involving new or preexisting conditions. In addition, we found that the ratio of copayments for brand name to generic drugs had a large positive effect on the GDR. The interventions did not appear to directly influence the GDR. Financial incentives expressed to consumers through benefit designs have a large influence on their switching to generic drugs and on the less-costly mail-order mode of purchase.
Gualano, Sarah K; Gurm, Hitinder S; Share, David; Smith, Dean; Aronow, Herbert D; LaLonde, Thomas; Bates, Eric R; Changezi, Hameem; McNamara, Richard; Moscucci, Mauro
2010-02-01
We sought to examine the temporal variations in the rate of both bare-metal stent (BMS) and drug-eluting stent (DES) use for off-label indications after the reports of an increased risk of very late stent thrombosis in patients with DES at the 2006 meeting of the European Society of Cardiology (ESC). To determine whether the decrease in use of DES has affected both on and off-label indications. The study cohort included patients undergoing coronary intervention in a large regional registry, the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2). Patient demographic and clinical characteristics for patients with DES in the third quarter of 2006 (pre-ESC) were compared to those from the fourth quarter of 2008 (post-guideline changes). Use of DES for off-label indications, such as ST-segment elevation myocardial infarction (STEMI), in-stent restenosis (ISR), and saphenous vein graft (SVG) interventions, were evaluated. The overall deployment of DES fell sharply from 83% pre-ESC to a plateau of 58% in the first quarter of 2008. This corresponded to a rise in BMS use, while angioplasty procedures stayed the same. The STEMI subgroup showed the most dramatic change, from 78% to only 36%. Off-label use in SVGs showed a similar trend, from 74% to 43%. Drug-eluting stent deployment for ISR was less affected, though it also fell 25% (from 79%-56%). The use of DES has fallen dramatically from June 2006 to December 2008, particularly for nonapproved indications. Our study provides a real-world assessment of contemporary change in DES use in response to the presentation of negative observational studies. Copyright 2010 Wiley Periodicals, Inc.
Improving medication adherence with a targeted, technology-driven disease management intervention.
Lawrence, David B; Allison, Wanda; Chen, Joyce C; Demand, Michael
2008-06-01
Treatment adherence is critical in managing chronic disease, but achieving it remains an elusive goal across many prevalent conditions. As part of its care management strategy, BlueCross BlueShield of South Carolina (BCBSSC) implemented the Longitudinal Adherence Treatment Evaluation program, a behavioral intervention to improve medication adherence among members with cardiovascular disease and/or diabetes. The objectives of this study were to 1) assess the effectiveness of telephonic intervention in influencing reinitiation of medication therapy, and 2) evaluate the rate and timing of medication reinitiation. BCBSSC applied algorithms against pharmacy claims data to identify patients prescribed targeted medications who were 60 or more days overdue for refills. This information was provided to care managers to address during their next patient contact. Care managers received focused training on techniques for medication behavior change, readiness to change, motivational interviewing, and active listening. Training also addressed common barriers to adherence and available resources, including side effect management, mail order benefits, drug assistance programs, medication organizers, and reminder systems. Overdue refills were tracked for 12 months, with medication reinitiation followed for an additional 3 months. In the intervention group, 94 patients were identified with 123 instances of late medication refills. In the age- and gender-matched comparison group, 61 patients were identified with 76 late refills. The intervention group had a significantly higher rate of medication reinitiation (59.3%) than the control group (42.1%; P < 0.05). Time to reinitiation was significantly shorter in the intervention group, 59.5 (+/- 69.0) days vs. 107.4 (+/- 109) days for the control group (P < 0.05). This initiative demonstrated that a targeted disease management intervention promoting patient behavior change increased the number of patients who reinitiated therapy after a period of nonadherence and decreased the time from nonadherence to adherence.
Looking beyond historical patient outcomes to improve clinical models.
Chia, Chih-Chun; Rubinfeld, Ilan; Scirica, Benjamin M; McMillan, Sean; Gurm, Hitinder S; Syed, Zeeshan
2012-04-25
Conventional algorithms for modeling clinical events focus on characterizing the differences between patients with varying outcomes in historical data sets used for the model derivation. For many clinical conditions with low prevalence and where small data sets are available, this approach to developing models is challenging due to the limited number of positive (that is, event) examples available for model training. Here, we investigate how the approach of developing clinical models might be improved across three distinct patient populations (patients with acute coronary syndrome enrolled in the DISPERSE2-TIMI33 and MERLIN-TIMI36 trials, patients undergoing inpatient surgery in the National Surgical Quality Improvement Program registry, and patients undergoing percutaneous coronary intervention in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry). For each of these cases, we supplement an incomplete characterization of patient outcomes in the derivation data set (uncensored view of the data) with an additional characterization of the extent to which patients differ from the statistical support of their clinical characteristics (censored view of the data). Our approach exploits the same training data within the derivation cohort in multiple ways to improve the accuracy of prediction. We position this approach within the context of traditional supervised (2-class) and unsupervised (1-class) learning methods and present a 1.5-class approach for clinical decision-making. We describe a 1.5-class support vector machine (SVM) classification algorithm that implements this approach, and report on its performance relative to logistic regression and 2-class SVM classification with cost-sensitive weighting and oversampling. The 1.5-class SVM algorithm improved prediction accuracy relative to other approaches and may have value in predicting clinical events both at the bedside and for risk-adjusted quality of care assessment.
Two-year impact of the alternative quality contract on pediatric health care quality and spending.
Chien, Alyna T; Song, Zirui; Chernew, Michael E; Landon, Bruce E; McNeil, Barbara J; Safran, Dana G; Schuster, Mark A
2014-01-01
To examine the 2-year effect of Blue Cross Blue Shield of Massachusetts' global budget arrangement, the Alternative Quality Contract (AQC), on pediatric quality and spending for children with special health care needs (CSHCN) and non-CSHCN. Using a difference-in-differences approach, we compared quality and spending trends for 126,975 unique 0- to 21-year-olds receiving care from AQC groups with 415,331 propensity-matched patients receiving care from non-AQC groups; 23% of enrollees were CSHCN. We compared quality and spending pre (2006-2008) and post (2009-2010) AQC implementation, adjusting analyses for age, gender, health risk score, and secular trends. Pediatric outcome measures included 4 preventive and 2 acute care measures tied to pay-for-performance (P4P), 3 asthma and 2 attention-deficit/hyperactivity disorder quality measures not tied to P4P, and average total annual medical spending. During the first 2 years of the AQC, pediatric care quality tied to P4P increased by +1.8% for CSHCN (P < .001) and +1.2% for non-CSHCN (P < .001) for AQC versus non-AQC groups; quality measures not tied to P4P showed no significant changes. Average total annual medical spending was ~5 times greater for CSHCN than non-CSHCN; there was no significant impact of the AQC on spending trends for children. During the first 2 years of the contract, the AQC had a small but significant positive effect on pediatric preventive care quality tied to P4P; this effect was greater for CSHCN than non-CSHCN. However, it did not significantly influence (positively or negatively) CSHCN measures not tied to P4P or affect per capita spending for either group.
Background Studies in CZT Detectors at Balloon Altitudes
NASA Astrophysics Data System (ADS)
Slavis, K. R.; Dowkontt, P. F.; Epstein, J. W.; Hink, P. L.; Matteson, J. L.; Duttweiler, F.; Huszar, G. L.; Leblanc, P. C.; Skelton, R. T.; Stephan, E. A.
1998-12-01
Cadmium Zinc Telluride (CZT) is a room temperature semiconductor detector well suited for high energy X-ray astronomy. We have developed a CZT detector with crossed strip readout, 500 micron resolution, and an advanced electrode design that greatly improves energy resolution. The latter varies from 3 keV to 6 keV FWHM over the range from 14-184 keV. We have conducted two balloon flights using this cross-strip detector and a standard planar detector sensitive in the energy range of 20-350 keV. These flights utilized a total of seven shielding schemes: 3 passive (7, 2, and 0 mm thick Pb/Sn/Cu), 2 active (NaI-CsI with 2 opening angles) and 2 hybrid passive-active. In the active shielding modes, the shield pulse heights were telemetered for each CZT event, allowing us to study the effect of shield energy-loss threshold on the background. The flights were launched from Fort Sumner, NM in October 1997 and May 1998, and had float altitudes of 109,000 and 105,000 feet respectively. Periodic energy calibrations showed the detector performance to be identical to that in the laboratory. The long duration of the May flight, 22 hours, enables us to study activation effects in the background. We present results on the effectiveness of each of the shielding schemes, activation effects and two new background reduction techniques for the strip detector. These reduction techniques employ the depth of interaction, as indicated by the ratio of cathode to anode pulse height, and multiple-site signatures to reject events that are unlikely to be X-rays incident on the detector's face. The depth of interaction technique reduces the background by a factor of 4 in the 20-40 keV energy range with passive shielding. Our preliminary results indicate a background level of 8.6x10(-3) cts/cm(2) -s-keV using passive shielding and 6x10(-4) cts/cm(2) -s-keV using active shielding in the 20-40 keV range.
77 FR 35741 - Petition for Waiver of Compliance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-14
... service. The end-to-end running time on the light rail Blue Line between Meadowview and Watt/Interstate 80... from 49 CFR Sections 229.125 and 234.105(c)(3) on SRTD's Blue and Gold Lines. In a letter dated July 28... shared highway-rail grade crossings on SRTD's Blue and Gold Lines. SRTD confirmed that 49 CFR part 222...
Absorption Cross-Sections of Sodium Diatomic Molecules
NASA Technical Reports Server (NTRS)
Fong, Zeng-Shevan
1985-01-01
The absorption cross sections of sodium dimers were studied using a heat pipe over operating in the non-heat-pipe mode. Three wavelength regions were observed. They are in the red, the green-blue, and the near ultraviolet regions. The absorption cross section depends on the wavelength of the incident light. Representative peak values for the v"=0 progression in the red and green-blue regions are 2.59 A sup 2 (average value) and 11.77 A sup 2 (T sub ave=624 K). The value for the C greater than X transitions is several tenths A sup 2. The cross sections were measured from absorption spectra taken as a function of temperature.
Copper transport mediated by nanocarrier systems in a blood-brain barrier in vitro model.
Fehse, Susanne; Nowag, Sabrina; Quadir, Mohiuddin; Kim, Kwang Sik; Haag, Rainer; Multhaup, Gerd
2014-05-12
Copper (Cu) is a cofactor of various metalloenzymes and has a role in neurodegenerative diseases with disturbed Cu homeostasis, for example, in Alzheimer's disease (AD) and Menkes disease. To address Cu imbalances, we synthesized two different dendritic nanoparticles (NP) for the transport of Cu(II) ions across the blood-brain barrier (BBB). The synthesized NPs show low toxicity and high water solubility and can stabilize high amounts of Cu(II). The Cu(II)-laden NPs crossed cellular membranes and increased the cellular Cu level. A human brain microvascular endothelial cell (HBMEC) model was established to investigate the permeability of the NPs through the BBB. By comparing the permeability × surface area product (PSe) of reference substances with those of NPs, we observed that NPs crossed the BBB model two times more effectively than (14)C-sucrose and sodium fluorescein (NaFl) and up to 60× better than Evans Blue labeled albumin (EBA). Our results clearly indicate that NPs cross the BBB model effectively. Furthermore, Cu was shielded by the NPs, which decreased the Cu toxicity. The novel design of the core-shell NP enabled the complexation of Cu(II) in the outer shell and therefore facilitated the pH-dependent release of Cu in contrast to core-multishell NPs, where the Cu(II) ions are encapsulated in the core. This allows a release of Cu into the cytoplasm. In addition, by using a cellular detection system based on a metal response element with green fluorescent protein (MRE-GFP), we demonstrated that Cu could also be released intracellularly from NPs and is accessible for biological processes. Our results indicate that NPs are potential candidates to rebalance metal-ion homeostasis in disease conditions affecting brain and neuronal systems.
High Dynamic Range Nonlinear Measurement using Analog Cancellation
2012-10-01
shield around sensitive areas. The target may also be sensitive to radiated coupling from the system and will benefit from a shield box or Faraday ... cage , if it is not already enclosed. On the shared measurement path and through the target, cross-channel coupling cannot be prevented, so low-PIM...testing is desired, traditional filtering is recommended, as the primary benefits of the analog canceller are effectively nullified. 2.4 Wideband
SUBGR: A Program to Generate Subgroup Data for the Subgroup Resonance Self-Shielding Calculation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Kang Seog
2016-06-06
The Subgroup Data Generation (SUBGR) program generates subgroup data, including levels and weights from the resonance self-shielded cross section table as a function of background cross section. Depending on the nuclide and the energy range, these subgroup data can be generated by (a) narrow resonance approximation, (b) pointwise flux calculations for homogeneous media; and (c) pointwise flux calculations for heterogeneous lattice cells. The latter two options are performed by the AMPX module IRFFACTOR. These subgroup data are to be used in the Consortium for Advanced Simulation of Light Water Reactors (CASL) neutronic simulator MPACT, for which the primary resonance self-shieldingmore » method is the subgroup method.« less
Chavez, III, Ramiro; Cai, Min; Tlach, Brian; ...
2016-01-20
Four new cross-conjugated small molecules based on a central benzo[1,2-d:4,5-d']bisoxazole moiety possessing semi-independently tunable HOMO and LUMO levels were synthesized and the properties of these materials were evaluated experimentally and theoretically. The molecules were thermally stable with 5% weight loss occurring well above 350 °C. The cruciforms all exhibited blue emission in solution ranging from 433–450 nm. Host–guest OLEDs fabricated from various concentrations of these materials using the small molecule host 4,4'-bis(9-carbazolyl)-biphenyl (CBP) exhibited deep blue-emission with Commission Internationale de L'Eclairage (CIE) coordinates of (0.15 ≤ x ≤ 0.17, 0.05 ≤ y ≤ 0.11), and maximum luminance efficiencies as highmore » as ~2 cd A–1. Lastly, these results demonstrate the potential of benzobisoxazole cruciforms as emitters for developing high-performance deep blue OLEDs.« less
Khanday, W A; Asif, M; Hameed, B H
2017-02-01
Cross-linked beads of activated oil palm ash zeolite/chitosan (Z-AC/C) composite were prepared through the hydrothermal treatment of NaOH activated oil palm ash followed by beading with chitosan. The effects of initial dye concentration (50-400mg/L), temperature (30°C-50°C) and pH (3-13) on batch adsorption of methylene blue (MB) and acid blue 29 (AB29) were studied. Adsorption of both dyes was better described by Pseudo-second-order kinetics and Freundlich isotherm model. The maximum adsorption capacities of Z-AC/C were 151.51, 169.49, and 199.20mg/g for MB and 212.76, 238.09, and 270.27mg/g for AB29 at 30°C, 40°C, and 50°C, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Singh, Vishwanath P.; Badiger, N. M.; El-Khayatt, A. M.
2014-06-01
We have computed γ-ray exposure buildup factors (EBF) of some building materials; glass, marble, flyash, cement, limestone, brick, plaster of paris (POP) and gypsum for energy 0.015-15 MeV up to 40 mfp (mfp, mean free path) penetration depth. Also, the macroscopic effective removal cross-sections (ΣR) for fast neutron were calculated. We discussed the dependency of EBF values on photon energy, penetration depth and chemical elements. The half-value layer and kinetic energy per unit mass relative to air of building materials were calculated for assessment of shielding effectiveness. Shielding thicknesses for glass, marble, flyash, cement, limestone and gypsum plaster (or Plaster of Paris, POP) were found comparable with ordinary concrete. Among the studied materials limestone and POP showed superior shielding properties for γ-ray and neutron, respectively. Radiation safety inside houses, schools and primary health centers for sheltering and annual dose can be assessed by the determination of shielding parameters of common building materials.
Contoured inner after-heater shield for reducing stress in growing crystalline bodies
Kalejs, Juris P.
1996-09-24
An apparatus for growing hollow crystalline bodies by the EFG process, comprising an EFG die having a top surface shaped for growing a hollow crystalline body having a cross-sectional configuration in the shape of a polygon having n faces, and a radiation shield adjacent to and surrounded by the top end surface of the die, characterized in that the shield has an inner edge defining a similar polygon with n sides, and the inner edge of the shield is notched so that the spacing between the n faces and the n sides is greatest between the central portions of the n faces and the n sides, whereby the greater spacing at the central portions helps to reduce lateral temperature gradients in the crystalline body that is grown by use of the die.
ERIC Educational Resources Information Center
Morizot, Olivier; Audureau, Eric; Briend, Jean-Yves; Hagel, Gaetan; Boulc'h, Florence
2015-01-01
In this article, we present two concrete applications of the concept of the human element to chemistry education; starting with a course and experimental project on blue pigment synthesis and concluding with cross-disciplinary lessons and experiments on blue photography. In addition to the description of the content of these courses, we explore…
Probing Sub-GeV Mass Strongly Interacting Dark Matter with a Low-Threshold Surface Experiment.
Davis, Jonathan H
2017-11-24
Using data from the ν-cleus detector, based on the surface of Earth, we place constraints on dark matter in the form of strongly interacting massive particles (SIMPs) which interact with nucleons via nuclear-scale cross sections. For large SIMP-nucleon cross sections, the sensitivity of traditional direct dark matter searches using underground experiments is limited by the energy loss experienced by SIMPs, due to scattering with the rock overburden and experimental shielding on their way to the detector apparatus. Hence, a surface-based experiment is ideal for a SIMP search, despite the much larger background resulting from the lack of shielding. We show using data from a recent surface run of a low-threshold cryogenic detector that values of the SIMP-nucleon cross section up to approximately 10^{-27} cm^{2} can be excluded for SIMPs with masses above 100 MeV.
Investigation of low-cost fabrication of ablative heat shields
NASA Technical Reports Server (NTRS)
Massions, V. P.; Mach, R. W.
1973-01-01
The fabrication, testing, and evaluation of materials and techniques employed in the fabrication of ablative heat shield panels are described. Results of this effort show projected reductions in labor man-hours for dielectric curing of panels when compared to panels molded in a steam-heated press. In addition, panels were fabricated with more than one density within the cross-section. These dual-density panels show significant weight and cost reduction potentials.
Spherical Harmonic Solutions to the 3D Kobayashi Benchmark Suite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, P.N.; Chang, B.; Hanebutte, U.R.
1999-12-29
Spherical harmonic solutions of order 5, 9 and 21 on spatial grids containing up to 3.3 million cells are presented for the Kobayashi benchmark suite. This suite of three problems with simple geometry of pure absorber with large void region was proposed by Professor Kobayashi at an OECD/NEA meeting in 1996. Each of the three problems contains a source, a void and a shield region. Problem 1 can best be described as a box in a box problem, where a source region is surrounded by a square void region which itself is embedded in a square shield region. Problems 2more » and 3 represent a shield with a void duct. Problem 2 having a straight and problem 3 a dog leg shaped duct. A pure absorber and a 50% scattering case are considered for each of the three problems. The solutions have been obtained with Ardra, a scalable, parallel neutron transport code developed at Lawrence Livermore National Laboratory (LLNL). The Ardra code takes advantage of a two-level parallelization strategy, which combines message passing between processing nodes and thread based parallelism amongst processors on each node. All calculations were performed on the IBM ASCI Blue-Pacific computer at LLNL.« less
Nuclear Fragmentation Processes Relevant for Human Space Radiation Protection
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2007-01-01
Space radiation from cosmic ray particles is one of the main challenges for human space explorations such-as a moon base or a trip to Mars. Models have been developed in order to predict the radiation exposure to astronauts and to evaluate the effectiveness of different shielding materials, and a key ingredient in these models is the physics of nuclear fragmentations. We have developed a semi-analytical method to determine which partial cross sections of nuclear fragmentations most affect the radiation dose behind shielding materials due to exposure to galactic cosmic rays. The cross sections thus determined will require more theoretical and/or experimental studies in order for us to better predict, reduce and mitigate the radiation exposure in human space explorations.
Stylish or safe blue-block eyewear
NASA Astrophysics Data System (ADS)
Ciosek, Jerzy
1998-10-01
The subject of modern, save and stylish eyewear is entertaining not only to people with unwell eyesight. Many people use glasses with anti-UV or blue-block coatings, glasses for driving or working with a computer. There were investigated the blue-block eyewear. There were analyzed reflected radiation at 300 - 400 nm wavelengths with cross- incidence. The traditional eyewear with classical or stylish frame may not protect sight against the UV radiation.
HZE reactions and data-base development
NASA Technical Reports Server (NTRS)
Townsend, Lawrence W.; Cucinotta, Francis A.; Wilson, John W.
1993-01-01
The primary cosmic rays are dispersed over a large range of linear energy transfer (LET) values and their distribution over LET is a determinant of biological response. This LET distribution is modified by radiation shielding thickness and shield material composition. The current uncertainties in nuclear cross sections will not allow the composition of the shield material to be distinguished in order to minimize biological risk. An overview of the development of quantum mechanical models of heavy ion reactions will be given and computational results compared with experiments. A second approach is the development of phenomenological models from semi-classical considerations. These models provide the current data base in high charge and energy (HZE) shielding studies. They will be compared with available experimental data. The background material for this lecture will be available as a review document of over 30 years of research at Langley but will include new results obtained over the last year.
Shielding techniques tackle EMI excesses. V - EMI shielding
NASA Astrophysics Data System (ADS)
Grant, P.
1982-10-01
The utilization of shielding gaskets in EMI design is presented in terms of seam design, gasket design, groove design, and fastener spacing. The main function of seam design is to minimize the coupling efficiency of a seam, and for effective shielding, seam design should include mating surfaces which are as flat as possible, and a flange width at least five times the maximum anticipated separation between mating surfaces. Seam surface contact with a gasket should be firm, continuous, and uniform. Gasket height, closure pressure, and compression set as a function of the applied pressure parameters are determined using compression/deflection curves. Environmental seal requirements are given and the most common materials used are neoprene, silicone, butadiene-acrylonitrile, and natural rubber. Groove design is also discussed, considering gasket heights and cross-sectional areas. Finally, fastener spacing is considered, by examining deflection as a percentage of gasket height.
Electronics Shielding and Reliability Design Tools
NASA Technical Reports Server (NTRS)
Wilson, John W.; ONeill, P. M.; Zang, Thomas A., Jr.; Pandolf, John E.; Koontz, Steven L.; Boeder, P.; Reddell, B.; Pankop, C.
2006-01-01
It is well known that electronics placement in large-scale human-rated systems provides opportunity to optimize electronics shielding through materials choice and geometric arrangement. For example, several hundred single event upsets (SEUs) occur within the Shuttle avionic computers during a typical mission. An order of magnitude larger SEU rate would occur without careful placement in the Shuttle design. These results used basic physics models (linear energy transfer (LET), track structure, Auger recombination) combined with limited SEU cross section measurements allowing accurate evaluation of target fragment contributions to Shuttle avionics memory upsets. Electronics shielding design on human-rated systems provides opportunity to minimize radiation impact on critical and non-critical electronic systems. Implementation of shielding design tools requires adequate methods for evaluation of design layouts, guiding qualification testing, and an adequate follow-up on final design evaluation including results from a systems/device testing program tailored to meet design requirements.
Neutron Physics Division progress report for period ending February 28, 1977
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maienschein, F.C.
1977-05-01
Summaries are given of research progress in the following areas: (1) measurements of cross sections and related quantities, (2) cross section evaluations and theory, (3) cross section processing, testing, and sensitivity analysis, (4) integral experiments and their analyses, (5) development of methods for shield and reactor analyses, (6) analyses for specific systems or applications, and (7) information analysis and distribution. (SDF)
Chung, Joonho; Matsuda, Yoshikazu; Nelson, Jessica; Keigher, Kiffon; Lopes, Demetrius K
2018-01-01
Objectives The Low-profile Visualized Intraluminal Support (LVIS) device is a flexible intracranial stent. The first generation of this system had significant challenges in consistently providing good wall apposition and aneurysm neck coverage. A new modified LVIS, LVIS Blue (Blue), has been developed to address these issues. The purpose of this study is to report a laboratory comparison of wall apposition and aneurysm neck coverage between the original LVIS and Blue. Methods In bench-top experiments, we noted the visual appearance of the devices and evaluated changes in stent cell angles, neck coverage surface area (%), and stent cell crossing profile for microcatheters using a fusiform aneurysm model. Our in vitro experiments included evaluation of wall apposition and aneurysm neck coverage of the devices under direct radiographic visualization. Results Blue showed three definite different zones (a mid-zone, a high-density zone, and a transitional zone) and higher metal coverage in the straight fusiform aneurysm model compared to LVIS. Two commercially available microcatheters easily crossed the stent cell at the greater curvature for both devices. In in vitro experiments, Blue showed better wall apposition in tortuous arteries and achieved higher neck coverage in the bifurcation aneurysm compared to LVIS. Discussion Blue achieved better wall apposition in tortuous arteries and higher aneurysm neck coverage (higher metal-to-artery ratio) in bifurcation aneurysms than LVIS. Our results may provide informative physical properties of LVIS and Blue to be expected when those are used for stent-assisted coil embolization of a large-giant fusiform aneurysm or a bifurcation saccular aneurysm clinically.
Small domes on Venus: Probable analogs of Icelandic lava shields
Garvin, James B.; Williams, Richard S.
1990-01-01
On the basis of observed shapes and volumetric estimates, we interpret small, dome-like features on radar images of Venus to be analogs of Icelandic lava-shield volcanoes. Using morphometric data for venusian domes in Aubele and Slyuta (in press), as well as our own measurements of representative dome volumes and areas from Tethus Regio, we demonstrate that the characteristic aspect ratios and flank slopes of these features are consistent with a subclass of low Icelandic lava-shield volcanoes (LILS ). LILS are slightly convex in cross-section with typical flank slopes of ∼3°. Plausible lava-shield-production rates for the venusian plains suggest formation of ∼53 million shields over the past 0.25 Ga. The cumulative global volume of lava that would be associated with this predicted number of lava shields is only a factor of 3–4 times that of a single oceanic composite shield volcano such as Mauna Loa. The global volume of all venusian lava shields in the 0.5–20-km size range would only contribute a meter of resurfacing over geologically significant time scales. Thus, venusian analogs to LILS may represent the most abundant landform on the globally dominant plains of Venus, but would be insignificant with regard to the global volume of lava extruded. As in Iceland, associated lavas from fissure eruptions probably dominate plains volcanism and should be evident on the higher resolution Magellan radar images.
NASA Astrophysics Data System (ADS)
Lee, Myoung-Jae; Jung, Young-Dae
2017-04-01
The collective nonideal effects on the nuclear fusion reaction process are investigated in partially ionized classical nonideal hydrogen plasmas. The effective pseudopotential model taking into account the collective and plasma shielding effects is applied to describe the interaction potential in nonideal plasmas. The analytic expressions of the Sommerfeld parameter, the fusion penetration factor, and the cross section for the nuclear fusion reaction in nonideal plasmas are obtained as functions of the nonideality parameter, Debye length, and relative kinetic energy. It is found that the Sommerfeld parameter is suppressed due to the influence of collective nonideal shielding. However, the collective nonideal shielding is found to enhance the fusion penetration factor in partially ionized classical nonideal plasmas. It is also found that the fusion penetration factors in nonideal plasmas represented by the pseudopotential model are always greater than those in ideal plasmas represented by the Debye-Hückel model. In addition, it is shown that the collective nonideal shielding effect on the fusion penetration factor decreases with an increase of the kinetic energy.
A Comparison of Monte Carlo and Deterministic Solvers for keff and Sensitivity Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haeck, Wim; Parsons, Donald Kent; White, Morgan Curtis
Verification and validation of our solutions for calculating the neutron reactivity for nuclear materials is a key issue to address for many applications, including criticality safety, research reactors, power reactors, and nuclear security. Neutronics codes solve variations of the Boltzmann transport equation. The two main variants are Monte Carlo versus deterministic solutions, e.g. the MCNP [1] versus PARTISN [2] codes, respectively. There have been many studies over the decades that examined the accuracy of such solvers and the general conclusion is that when the problems are well-posed, either solver can produce accurate results. However, the devil is always in themore » details. The current study examines the issue of self-shielding and the stress it puts on deterministic solvers. Most Monte Carlo neutronics codes use continuous-energy descriptions of the neutron interaction data that are not subject to this effect. The issue of self-shielding occurs because of the discretisation of data used by the deterministic solutions. Multigroup data used in these solvers are the average cross section and scattering parameters over an energy range. Resonances in cross sections can occur that change the likelihood of interaction by one to three orders of magnitude over a small energy range. Self-shielding is the numerical effect that the average cross section in groups with strong resonances can be strongly affected as neutrons within that material are preferentially absorbed or scattered out of the resonance energies. This affects both the average cross section and the scattering matrix.« less
Design of Composite Hip Prostheses Considering the Long-Term Behavior of the Femur
NASA Astrophysics Data System (ADS)
Lim, Jong Wan; Jeong, Jae Youn; Ha, Sung Kyu
A design method for the hip prosthesis is proposed which can alleviate problems associated with stress shielding, proximal loosening and the high stress of bone-implant interfaces after total hip replacement. The stress shielding which may lead to bone resorption, can cause a loosening of the stem and a fracture of femoral bone. Generally the composites were more suitable for hip prosthesis material in the long-term stability than metallic alloy because design cases of composite materials produced less stress shielding than titanium alloy. A bone remodeling algorithm was implemented in a nonlinear finite element program to predict the long-term performance of the hip prosthesis. The three neck shapes and three cross sections of composite hip were examined. It was found that the stress concentration in the distal region of the titanium stem which may cause the patient's thigh pains was reduced using composite material. The head neck shape was closely related with the cortical bone resorption and the cancellous bone apposition at proximal region whereas the cross-section was closely related with the relative micromotion between interfaces. The convex head neck type with the quadrangle cross-section produced less subsidence at proximal region on the medial side than the others. For all composite material cases, the cancellous bone apposition occurred at partial interfaces, which may result in a stable bio-fixation. The design performances of the convex neck head type with the hexagonal cross-section designed to insure the long-term stability were found to be more suitable than the others.
E-beam-Cure Fabrication of Polymer Fiber/Matrix Composites for Multifunctional Radiation Shielding
NASA Technical Reports Server (NTRS)
Wilson, John W.; Jensen, Brian J.; Thibeault, Sheila A.; Hou, Tan-Hung; Saether, Erik; Glaessgen, Edward H.; Humes, Donald H.; Chang, Chie K.; Badavi, Francis F.; Kiefer, Rrichard L.;
2004-01-01
Aliphatic polymers were identified as optimum radiation polymeric shielding materials for building multifunctional structural elements. Conceptual damage-tolerant configurations of polyolefins have been proposed but many issues on the manufacture remain. In the present paper, we will investigate fabrication technologies with e-beam curing for inclusion of high-strength aliphatic polymer fibers into a highly cross-linked polyolefin matrix. A second stage of development is the fabrication methods for applying face sheets to aliphatic polymer closed-cell foams.
Genetic separation of phototropism from blue light inhibition of hypocotyl elongation on Arabidopsis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liscum, E.; Young, J.C.; Hangarter, R.P.
1991-05-01
Phototropism and inhibition of stem elongation occur in response to blue light-induced inhibition of cell elongation. However, phototropism is a low fluence response and inhibition of hypocotyl elongation is a high irradiance response. The authors have isolated several mutant lines of Arabidopsis which lack blue light-induced inhibition of hypocotyl elongation but retain normal phototropic functions. In addition, a mutant line which completely lacks the phototropic response retains normal blue light-induced inhibition of hypocotyl elongation. F1 progeny of crosses between these two mutant classes exhibited wild-type phototropism and inhibition of hypocotyl elongation in response to blue light stimuli. In the F2more » generation, one in sixteen seedlings were double mutants lacking both phototropism and blue light-induced hypocotyl growth inhibition. These studies conclusively show that blue light-induced phototropism and hypocotyl growth inhibition function through genetically distinct signal transduction or response systems.« less
Neutron detection with a NaI spectrometer using high-energy photons
NASA Astrophysics Data System (ADS)
Holm, Philip; Peräjärvi, Kari; Sihvonen, Ari-Pekka; Siiskonen, Teemu; Toivonen, Harri
2013-01-01
Neutrons can be indirectly detected by high-energy photons. The performance of a 4″×4″×16″ NaI portal monitor was compared to a 3He-based portal monitor with a comparable cross-section of the active volume. Measurements were performed with bare and shielded 252Cf and AmBe sources. With an optimum converter and moderator structure for the NaI detector, the detection efficiencies and minimum detectable activities of the portal monitors were similar. The NaI portal monitor preserved its detection efficiency much better with shielded sources, making the method very interesting for security applications. For heavily shielded sources, the NaI detector was 2-3 times more sensitive than the 3He-based detector.
Description of alpha-nucleus interaction cross sections for cosmic ray shielding studies
NASA Technical Reports Server (NTRS)
Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.
1993-01-01
Nuclear interactions of high-energy alpha particles with target nuclei important for cosmic ray studies are discussed. Models for elastic, quasi-elastic, and breakup reactions are presented and compared with experimental data. Energy-dependent interaction cross sections and secondary spectra are presented based on theoretical models and the limited experimental data base.
NASA Astrophysics Data System (ADS)
Obaid, Shamsan S.; Sayyed, M. I.; Gaikwad, D. K.; Pawar, Pravina. P.
2018-07-01
In the present work, the mass attenuation coefficient μ/ρ is investigated experimentally and theoretically for seven rocks (olivine basalt, green marble, jet black granite, telphone black granite, cuddapah limestone, white marble and pink marble). The rock samples were collected from different places of India. The mass attenuation coefficients of the samples were measured experimentally at photon energies of radioisotopes Co57 (122 keV), Ba133 (356 keV), 22Na (511 and 1275 keV), Cs137 (662 keV), Mn54 (840 keV), and Co60 (1330 keV). Theoretically, the simulation results of μ/ρ using both XCOM and MCNP5 codes were compared with experimental results and a satisfactory agreement was observed. Total atomic cross sections (σt,a) electronic cross sections (σt,e), effective atomic number (Zeff), electron density (Ne) and half value layer (HVL) were evaluated using the obtained μ/ρ values for investigated rocks. The HVL values for the selected rocks were compared with some common shielding concretes. Moreover, by Geometric Progression method (G-P) exposure buildup factor (EBF) and energy absorption buildup factor (EABF) values were calculated for incident photon energy 0.015-15 MeV up to penetration depths of 40 mean free paths. The results show that among the studied rocks pink marble possesses superior shielding properties for γ-ray. This work was carried out to explore the advantage of utilizing the selected rocks in engineering structures and building construction to shield gamma-rays.
Total Ambient Dose Equivalent Buildup Factor Determination for Nbs04 Concrete.
Duckic, Paulina; Hayes, Robert B
2018-06-01
Buildup factors are dimensionless multiplicative factors required by the point kernel method to account for scattered radiation through a shielding material. The accuracy of the point kernel method is strongly affected by the correspondence of analyzed parameters to experimental configurations, which is attempted to be simplified here. The point kernel method has not been found to have widespread practical use for neutron shielding calculations due to the complex neutron transport behavior through shielding materials (i.e. the variety of interaction mechanisms that neutrons may undergo while traversing the shield) as well as non-linear neutron total cross section energy dependence. In this work, total ambient dose buildup factors for NBS04 concrete are calculated in terms of neutron and secondary gamma ray transmission factors. The neutron and secondary gamma ray transmission factors are calculated using MCNP6™ code with updated cross sections. Both transmission factors and buildup factors are given in a tabulated form. Practical use of neutron transmission and buildup factors warrants rigorously calculated results with all associated uncertainties. In this work, sensitivity analysis of neutron transmission factors and total buildup factors with varying water content has been conducted. The analysis showed significant impact of varying water content in concrete on both neutron transmission factors and total buildup factors. Finally, support vector regression, a machine learning technique, has been engaged to make a model based on the calculated data for calculation of the buildup factors. The developed model can predict most of the data with 20% relative error.
Scoping studies of shielding to reduce the shutdown dose rates in the ITER ports
NASA Astrophysics Data System (ADS)
Juárez, R.; Guirao, J.; Pampin, R.; Loughlin, M.; Polunovskiy, E.; Le Tonqueze, Y.; Bertalot, L.; Kolsek, A.; Ogando, F.; Udintsev, V.; Walsh, M.
2018-07-01
The planned in situ maintenance tasks in the ITER port interspace are fundamental to ensure the operation of equipment to control, evaluate and optimize the plasma performance during the entire facility lifetime. They are subject to a limit of shutdown dose rates (SDDR) of 100 µSv h‑1 after 106 s of cooling time, which is nowadays a design driver for the port plugs as well as the application of ALARA. Three conceptual shielding proposals outside the ITER ports are studied in this work to support the achievement of this objective. Considered one by one, they offer reductions ranging from 25% to 50%, which are rather significant. This paper shows that, by combining these shields, the SDDR as low as 57Δ µSv h‑1 can be achieved with a local approach considering only radiation from one port (no cross-talk form neighboring ports). The locally evaluated SDDR are well below the limit which is an essential pre-requisite for achieving 100µSv h‑1 in a global analysis including all contributions. Further studies will have to deal with a realistic port plug design and the cross-talks from neighbour ports.
Mate choice and imprinting in birds studied by cross-fostering in the wild.
Slagsvold, Tore; Hansen, Bo T; Johannessen, Lars E; Lifjeld, Jan T
2002-01-01
Sexual-selection theories generally assume that mating preferences are heritable traits. However, there is substantial evidence that the rearing environment may be important for the development of mating preferences, indicating that they may be learnt, or modified by experience. The relative importance of such sexual imprinting across species remains largely unexplored. Here, we report results of a large-scale cross-fostering experiment in the wild in which nestling birds were raised by parents of a different species. We show that resulting sexual imprinting may have a negative effect on pairing success in one species (the great tit, Parus major), but not in two other species (the blue tit, P. caeruleus and the pied flycatcher, Ficedula hypoleuca). A remarkable variation thus seems to exist, even between species that are congeneric and have similar breeding ecologies. The cross-fostering resulted in heterospecific pairings between the two tit species (female blue tit breeding with male great tit), which has never, to our knowledge, been previously documented. However, the chicks fledging from these nests were all blue tit. PMID:12137574
Two-dimensional wide-band-gap nitride semiconductors: Single-layer 1 T -X N2 (X =S ,Se , and Te )
NASA Astrophysics Data System (ADS)
Lin, Jia-He; Zhang, Hong; Cheng, Xin-Lu; Miyamoto, Yoshiyuki
2016-11-01
Recently, the two-dimensional (2D) semiconductors arsenene and antimonene, with band gaps larger than 2.0 eV, have attracted tremendous interest, especially for potential applications in optoelectronic devices with a photoresponse in the blue and UV range. Motivated by this exciting discovery, types of highly stable wide-band-gap 2D nitride semiconductors were theoretically designed. We propose single-layer 1 T -X N2 (X =S , Se, and Te) via first-principles simulations. We compute 1 T -X N2 (X =S , Se, and Te) with indirect band gaps of 2.825, 2.351, and 2.336 eV, respectively. By applying biaxial strain, they are able to induce the transition from a wide-band-gap semiconductor to a metal, and the range of absorption spectra of 1 T -X N2 (X =S , Se, and Te) obviously extend from the ultraviolet region to the blue-purple light region. With an underlying graphene, we find that 1 T -X N2 can completely shield the light absorption of graphene in the range of 1-1.6 eV. Our research paves the way for optoelectronic devices working under blue or UV light, and mechanical sensors based on these 2D crystals.
1981-10-01
S82-31408 (May 1983) --- The Spacelab 2 emblem is a symbolic representation of the scientific objectives of the mission. The emblem is in the shape of a triangular shield with convexly curved edges. Across the top of a black out border are the words ?SPACELAB 2?. Within the black border is a sky blue border carryhing the words: ?ASTRONOMY?, ON TOP? ?PHYSICS?, on the left; and ?BIOLOGY?, on the right. Within the blue border is a schematic view of the sun, the earth, and the orbiter with Spacelab 2. The sun appears in the upper right background as a white disc surrounded by six concentric rings ranging grom bright yellow near the disc through yellow-red to a dark red out ring. A sector of the earth with blue ocean and a black portion of North America is in the upper left corner. The black and white Orbiter is seen from directly overhead in the foreground, the right side illuminated by the sun, the left side in shadow. Although the payload bay doors are not open, the Spacelab 2 payload is seen as if the doors were open. In black on white are seen the three pallets, and the separately mounted cosmic ray experiment at the aft end of the bay.
Herr, Raphael M; Bosch, Jos A; van Vianen, Annelies E M; Jarczok, Marc N; Thayer, Julian F; Li, Jian; Schmidt, Burkhard; Fischer, Joachim E; Loerbroks, Adrian
2015-06-01
Perceived injustice at work predicts coronary heart disease. Vagal dysregulation represents a potential psychobiological pathway. We examined associations between organizational justice and heart rate variability (HRV) indicators. Grounded in social exchange and psychological contract theory, we tested predictions that these associations are more pronounced among white-collar than among blue-collar workers. Cross-sectional data from 222 blue-collar and 179 white-collar men were used. Interactional and procedural justice were measured by questionnaire. Ambulatory HRV was assessed across 24 h. Standardized regression coefficients (β) were calculated. Among white-collar workers, interactional justice showed positive relationships with 24-h HRV, which were strongest during sleeping time (adjusted βs≥0.26; p values≤0.01). No associations were found for blue-collar workers. A comparable but attenuated pattern was observed for procedural justice. Both dimensions of organizational injustice were associated with lowered HRV among white-collar workers. The impact of justice and possibly its association with health seems to differ by occupational groups.
Homer, Michael D.; Peterson, James T.; Jennings, Cecil A.
2015-01-01
Back-calculation of length-at-age from otoliths and spines is a common technique employed in fisheries biology, but few studies have compared the precision of data collected with this method for catfish populations. We compared precision of back-calculated lengths-at-age for an introducedIctalurus furcatus (Blue Catfish) population among 3 commonly used cross-sectioning techniques. We used gillnets to collect Blue Catfish (n = 153) from Lake Oconee, GA. We estimated ages from a basal recess, articulating process, and otolith cross-section from each fish. We employed the Frasier-Lee method to back-calculate length-at-age for each fish, and compared the precision of back-calculated lengths among techniques using hierarchical linear models. Precision in age assignments was highest for otoliths (83.5%) and lowest for basal recesses (71.4%). Back-calculated lengths were variable among fish ages 1–3 for the techniques compared; otoliths and basal recesses yielded variable lengths at age 8. We concluded that otoliths and articulating processes are adequate for age estimation of Blue Catfish.
THE SURVEY OF H I IN EXTREMELY LOW-MASS DWARFS (SHIELD)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cannon, John M.; Engstrom, Eric; Allan, John
We present first results from the Survey of H I in Extremely Low-mass Dwarfs (SHIELD), a multi-configuration Expanded Very Large Array (EVLA) study of the neutral gas contents and dynamics of galaxies with H I masses in the 10{sup 6}-10{sup 7} M{sub sun} range detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. We describe the survey motivation and concept demonstration using Very Large Array imaging of six low-mass galaxies detected in early ALFALFA data products. We then describe the primary scientific goals of SHIELD and present preliminary EVLA and WIYN 3.5 m imaging of the 12 SHIELD galaxies. Withmore » only a few exceptions, the neutral gas distributions of these extremely low-mass galaxies are centrally concentrated. In only one system have we detected H I column densities higher than 10{sup 21} cm{sup -2}. Despite this, the stellar populations of all of these systems are dominated by blue stars. Further, we find ongoing star formation as traced by H{alpha} emission in 10 of the 11 galaxies with H{alpha} imaging obtained to date. Taken together these results suggest that extremely low-mass galaxies are forming stars in conditions different from those found in more massive systems. While detailed dynamical analysis requires the completion of data acquisition, the most well-resolved system is amenable to meaningful position-velocity analysis. For AGC 749237, we find well-ordered rotation of 30 km s{sup -1} at {approx}40'' distance from the dynamical center. At the adopted distance of 3.2 Mpc, this implies the presence of a {approx}>1 x 10{sup 8} M{sub sun} dark matter halo and a baryon fraction {approx}<0.1.« less
NASA Technical Reports Server (NTRS)
Ko, William L.
2004-01-01
Heat-transfer, thermal bending, and mechanical buckling analyses have been performed on a superalloy "honeycomb" thermal protection system (TPS) for future hypersonic flight vehicles. The studies focus on the effect of honeycomb cell geometry on the TPS heat-shielding performance, honeycomb cell wall buckling characteristics, and the effect of boundary conditions on the TPS thermal bending behavior. The results of the study show that the heat-shielding performance of a TPS panel is very sensitive to change in honeycomb core depth, but insensitive to change in honeycomb cell cross-sectional shape. The thermal deformations and thermal stresses in the TPS panel are found to be very sensitive to the edge support conditions. Slight corrugation of the honeycomb cell walls can greatly increase their buckling strength.
Determination of Important Nuclear Fragmentation Processes for Human Space Radiation Protection
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2007-01-01
We present a semi-analytical method to determine which partial cross sections of nuclear fragmentations most affect the shielded dose equivalent due to exposure to galactic cosmic rays. The cross sections thus determined will require more theoretical and/or experimental studies in order for us to better predict, reduce and mitigate the radiation exposure in human space explorations.
Electromagnetic dissociation effects in galactic heavy-ion fragmentation
NASA Technical Reports Server (NTRS)
Norbury, J. W.; Townsend, L. W.
1986-01-01
Methods for calculating cross sections for the breakup of galactic heavy ions by the Coulomb fields of the interacting nuclei are presented. By using the Weizsacker-Williams method of virtual quanta, estimates of electromagnetic dissociation cross sections for a variety of reactions applicable to galactic cosmic ray shielding studies are presented and compared with other predictions and with available experimental data.
Scalable Loading of a Two-Dimensional Trapped-Ion Array
2015-11-25
ion -trap array based on two crossed photo-ionization laser beams . With the use of a continuous flux of pre-cooled neutral...push laser Atomic beam Dierential pumping tube Push laser 2D-MOT 50 K Shield 4 K Shield 4 K stage Trap chip MOT laser Ion To ion pump 5s2 1S0 461...conducted a series of Ramsey experiments on a single trapped ion in the presence and absence of neu- tral atom flux as well as each of the PI laser
NASA Astrophysics Data System (ADS)
Cramer, S. N.; Roussin, R. W.
1981-11-01
A Monte Carlo analysis of a time-dependent neutron and secondary gamma-ray integral experiment on a thick concrete and steel shield is presented. The energy range covered in the analysis is 15-2 MeV for neutron source energies. The multigroup MORSE code was used with the VITAMIN C 171-36 neutron-gamma-ray cross-section data set. Both neutron and gamma-ray count rates and unfolded energy spectra are presented and compared, with good general agreement, with experimental results.
Lavie, N
1997-05-01
Predictions from Treisman's feature integration theory of attention were tested in a variant of the response-competition paradigm. Subjects made choice responses to particular color-shape conjunctions (e.g., a purple cross vs. a green circle) while withholding their responses to the opposite conjunctions (i.e., a purple circle vs. a green cross). The results showed that compatibility effects were based on both distractor color and shape. For unattended distractors in preknown irrelevant positions, compatibility effects were equivalent for conjunctive distractors (e.g., a purple cross and a blue triangle) and for disjunctive distractors (e.g., a purple triangle and a blue cross). Manipulation of attention to the distractors positions resulted in larger compatibility effects from conjoined features. These results accord with Treisman's claim that correct conjunction information is unavailable under conditions of inattention, and they provide new information on response-competition effects from multiple features.
Genetic separation of phototropism and blue light inhibition of stem elongation
NASA Technical Reports Server (NTRS)
Liscum, E.; Young, J. C.; Poff, K. L.; Hangarter, R. P.
1992-01-01
Blue light-induced regulation of cell elongation is a component of the signal response pathway for both phototropic curvature and inhibition of stem elongation in higher plants. To determine if blue light regulates cell elongation in these responses through shared or discrete pathways, phototropism and hypocotyl elongation were investigated in several blue light response mutants in Arabidopsis thaliana. Specifically, the blu mutants that lack blue light-dependent inhibition of hypocotyl elongation were found to exhibit a normal phototropic response. In contrast, a phototropic null mutant (JK218) and a mutant that has a 20- to 30-fold shift in the fluence dependence for first positive phototropism (JK224) showed normal inhibition of hypocotyl elongation in blue light. F1 progeny of crosses between the blu mutants and JK218 showed normal phototropism and inhibition of hypocotyl elongation, and approximately 1 in 16 F2 progeny were double mutants lacking both responses. Thus, blue light-dependent inhibition of hypocotyl elongation and phototropism operate through at least some genetically distinct components.
NASA Astrophysics Data System (ADS)
Miyahara, Tomoko; Koda, Ai; Sekiguchi, Rikuko; Amemiya, Toshihiko
In this study, we investigated the nature of cross-modal associations between colors and vowels. In Experiment 1, we examined the patterns of synesthetic correspondence between colors and vowels in a perceptual similarity experiment. The results were as follows: red was chosen for /a/, yellow was chosen for /i/, and blue was chosen for /o/ significantly more than any other vowels. Interestingly this pattern of correspondence is similar to the pattern of colored hearing reported by synesthetes. In Experiment 2, we investigated the robustness of these cross-modal associations using an implicit association test (IAT). A clear congruence effect was found. Participants responded faster in congruent conditions (/i/ and yellow, /o/ and blue) than in incongruent conditions (/i/ and blue, /o/ and yellow). This result suggests that the weak synesthesia between vowels and colors in non-synesthtes is not the fact of mere conscious choice, but reflects some underlying implicit associations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stimpson, Shane G.; Liu, Yuxuan; Collins, Benjamin S.
An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilitiesmore » have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Furthermore given these performance benefits, these approaches have been adopted as the default in MPACT.« less
Stimpson, Shane G.; Liu, Yuxuan; Collins, Benjamin S.; ...
2017-07-17
An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilitiesmore » have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Furthermore given these performance benefits, these approaches have been adopted as the default in MPACT.« less
Suppression of vagal cardiac modulation by blue light in healthy subjects.
Yuda, Emi; Ogasawara, Hiroki; Yoshida, Yutaka; Hayano, Junichiro
2016-10-05
In the contemporary life environments, our body is increasingly exposed to various sources of colored light, which may affect our physiological functions as non-image-forming effects. We examined the impacts of colored lights on the autonomic functions by the analysis of heart rate variability (HRV). A lighting device consisting of four organic light-emitting diode (OLED) modules (55 × 55 mm 2 ) with adjustable red-green-blue color was secured 24 cm above the eyes of subject lying supine in a light-shielded laboratory. Following a 15-min supine rest, electrocardiogram and respiration were measured continuously during 3-min darkness, 6-min colored OLED illumination, and 3-min darkness under paced breathing (15 breath/min). The measurements were repeated at a 45-min interval for red, green, and blue lights with melanopsin-stimulating photon flux density (MSPFD) of 0.00, 0.10, and 0.20 μmol/m 2 /s, respectively, in 12 healthy subjects (23 ± 2 years, two females). Additionally, the effects of blue lights with 0.20, 0.10, and 0.04 μmol/m 2 /s MSPFD were examined in four healthy subjects (25-39 years, two females). HRV was analyzed for low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.20-0.30 Hz) power and LF-to-HF ratio (LF/HF). Compared to darkness before lighting, HF power decreased (P < 0.001) and LF/HF increased (P = 0.024) during lighting on average of all color lights, whereas HF power showed a greater decrease with blue light than with red and green lights (P < 0.05 for both). The decrease in HF power lasted even during darkness after lighting (P < 0.001). HF power decreased with blue light with 0.20 μmol/m 2 /s MSPFD (P < 0.001) but not with that with 0.10 or 0.04 μmol/m 2 /s (P = 0.1 and 0.9, respectively). Vagal cardiac modulation is suppressed by OLED blue light in healthy subjects most likely through melanopsin-dependent non-image-forming effect.
Song, Chris; Sukul, Devraj; Seth, Milan; Wohns, David; Dixon, Simon R; Slocum, Nicklaus K; Gurm, Hitinder S
2018-06-01
Because of shared risk factors between coronary artery disease and cerebrovascular disease, patients with a history of transient ischemic attack (TIA) or stroke are at greater risk of developing coronary artery disease, which may require percutaneous coronary intervention (PCI). However, there remains a paucity of research examining outcomes after PCI in these patients. We analyzed consecutive patients who underwent PCI between January 1, 2013, and March 31, 2016, at 47 Michigan hospitals and identified those with a history of TIA/stroke. We used propensity score matching to adjust for differences in baseline characteristics and compared in-hospital outcomes between patients with and without a history of TIA/stroke. We compared rates of 90-day readmission and long-term mortality in a subset of patients. Among 98 730 patients who underwent PCI, 10 915 had a history of TIA/stroke. After matching (n=10 618 per group), a history of TIA/stroke was associated with an increased risk of in-hospital stroke (adjusted odds ratio, 2.04; 95% confidence interval, 1.41-2.96; P <0.001). There were no differences in the risks of other in-hospital outcomes. In a subset of patients with postdischarge data, a history of TIA/stroke was associated with increased risks of 90-day readmission (adjusted odds ratio, 1.22; 95% confidence interval, 1.09-1.38; P <0.001) and long-term mortality (hazard ratio, 1.23; 95% confidence interval, 1.07-1.43; P =0.005). A history of TIA/stroke was common in patients who underwent PCI and was associated with increased risks of in-hospital stroke, 90-day readmission, and long-term mortality. Given the devastating consequences of post-PCI stroke, patients with a history of TIA/stroke should be counseled on this increased risk before undergoing PCI. © 2018 American Heart Association, Inc.
Plaisance, Benjamin R; Munir, Khan; Share, David A; Mansour, M Ashraf; Fox, James M; Bove, Paul G; Riba, Arthur L; Chetcuti, Stanley J; Gurm, Hitinder S; Grossman, P Michael
2011-06-01
This study sought to evaluate the effect of age on procedure type, periprocedural management, and in-hospital outcomes of patients undergoing lower-extremity (LE) peripheral vascular intervention (PVI). Surgical therapy of peripheral arterial disease is associated with significant morbidity and mortality in the elderly. There are limited data related to the influence of advanced age on the outcome of patients undergoing percutaneous LE PVI. Clinical presentation, comorbidities, and in-hospital outcomes of patients undergoing LE PVI in a multicenter, multidisciplinary registry were compared between 3 age groups: < 70 years, between 70 and 80 years, and ≥ 80 years (elderly group). In our cohort, 7,769 patients underwent LE PVI. The elderly patients were more likely to be female and to have a greater burden of comorbidities. Procedural success was lower in the elderly group (74.2% for age ≥ 80 years vs. 78% for age 70 to < 80 years and 81.4% in patients age < 70 years, respectively; p < 0.0001). Unadjusted rates of procedure-related vascular access complications, post-procedure transfusion, contrast-induced nephropathy, amputation, and major adverse cardiac events were higher in elderly patients. After adjustment for baseline covariates, the elderly patients were more likely to experience vascular access complications; however, advanced age was not found to be associated with major adverse cardiac events, transfusion, contrast-induced nephropathy, or amputation. Contemporary PVI can be performed in elderly patients with high procedural and technical success with low rates of periprocedural complications including mortality. These findings may support the notion of using PVI as a preferred revascularization strategy in the treatment of severe peripheral arterial disease in the elderly population. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Stuart, Elizabeth A.; Huskamp, Haiden A.; Duckworth, Kenneth; Simmons, Jeffrey; Song, Zirui; Chernew, Michael; Barry, Colleen L.
2014-01-01
Difference-in-difference (DD) methods are a common strategy for evaluating the effects of policies or programs that are instituted at a particular point in time, such as the implementation of a new law. The DD method compares changes over time in a group unaffected by the policy intervention to the changes over time in a group affected by the policy intervention, and attributes the “difference-in-differences” to the effect of the policy. DD methods provide unbiased effect estimates if the trend over time would have been the same between the intervention and comparison groups in the absence of the intervention. However, a concern with DD models is that the program and intervention groups may differ in ways that would affect their trends over time, or their compositions may change over time. Propensity score methods are commonly used to handle this type of confounding in other non-experimental studies, but the particular considerations when using them in the context of a DD model have not been well investigated. In this paper, we describe the use of propensity scores in conjunction with DD models, in particular investigating a propensity score weighting strategy that weights the four groups (defined by time and intervention status) to be balanced on a set of characteristics. We discuss the conceptual issues associated with this approach, including the need for caution when selecting variables to include in the propensity score model, particularly given the multiple time point nature of the analysis. We illustrate the ideas and method with an application estimating the effects of a new payment and delivery system innovation (an accountable care organization model called the “Alternative Quality Contract” (AQC) implemented by Blue Cross Blue Shield of Massachusetts) on health plan enrollee out-of-pocket mental health service expenditures. We find no evidence that the AQC affected out-of-pocket mental health service expenditures of enrollees. PMID:25530705
NASA Astrophysics Data System (ADS)
Liu, Suyang; Ganduglia, Cecilia M.; Li, Xiao; Delclos, George L.; Franzini, Luisa; Zhang, Kai
2016-12-01
A number of time-series studies have associated PM2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) mass and components with various health outcomes. No studies have yet examined the associations between PM2.5 components and hospital admissions among a privately insured population. We estimated the short-term associations between exposure to PM2.5 mass and components and emergency hospital admissions for all-cause and cause-specific diseases in Greater Houston, Texas, during 2008-2013 using Blue Cross Blue Shield Texas claims data. A total of 90,085 emergency hospital admissions were included in this study, with an average of 34 ± 10 admissions per day. We selected 20 PM2.5 components from the U.S. Environmental Protection Agency's Chemical Speciation Network site located in Houston, and then applied Poisson regression models to assess the short-term effects of PM2.5 mass and species on emergency hospital admissions. Effects were estimated without adjustment for other airborne pollutants. PM2.5 mass was not statistically significantly associated with increased all-cause emergency hospital admissions and selected cause-specific admissions. For selected PM2.5 species, we found interquartile range increases in arsenic (0.001 μg/m3) and copper (0.017 μg/m3) were significantly (P < 0.05) associated with increased admissions for stroke, (5.98% [95% confidence interval (CI): 0.73, 11.50%]) and pneumonia (4.07% [95% CI: 0.37, 7.90%]), respectively. Seasonal analysis showed weak variation among PM2.5 mass and components, except that nickel significantly increased all-cause emergency hospital admissions (2.16% [95% CI: 0.21, 4.14%]) during the warm season. Our findings suggest that hospital admissions in the privately insured population are slightly affected by ambient fine particulate matter air pollution.
Hoy, Tracey; Singhal, Puneet K; Willey, Vincent J; Insinga, Ralph P
2009-10-01
This study examined the incidence of and healthcare costs attributable to genital warts within a large US commercially insured, geographically dispersed population. Using a retrospective cohort study design, this longitudinal analysis assessed administrative claims of integrated medical and pharmacy encounters from five Blue Cross Blue Shield health plans. Genital warts cases were identified using a methodology previously described by Insinga et al. Age- and gender-specific incidence of genital warts per 1000 person-years in 2004, and duration-of-episode attributable direct medical costs (2004 US dollars) and healthcare resource utilization of cases diagnosed in 2002. Overall outcome measures were age- and gender-adjusted to the 2004 US civilian population. Genital warts incidence in 2004 was 1.2/1000 females and 1.1/1000 males. Incidence was highest among females aged 20-24 (4.6/1000) and males aged 25-29 (2.7/1000). Projected overall incidence was over 340,000 cases in 2004. Mean duration-of-episode per incident case in 2002 was 95.4 days (males 116.3 days; females 69.7 days). Mean ambulatory visits per episode were 1.5 for females and 1.9 for males, with <1 drug prescription/episode. Mean costs were $647/episode ($745 males; $528 females). The 2004 estimated economic burden was $760 per 1000 individuals in the general population with the total exceeding $220 million. Only those genital warts cases that sought evaluation or for which the treating provider was covered by the health plan were captured in the study. Genital warts represent a significant health and cost burden in the US. Adoption of novel healthcare technologies such as vaccines along with traditional interventions such as physician education of signs and symptoms, condom use and abstinence or limiting number of sexual partners may significantly help reduce the burden of genital warts.
Changes in Health Care Spending and Quality 4 Years into Global Payment
Song, Zirui; Rose, Sherri; Safran, Dana G.; Landon, Bruce E.; Day, Matthew P.; Chernew, Michael E.
2014-01-01
BACKGROUND Spending and quality under global budgets remain unknown beyond 2 years. We evaluated spending and quality measures during the first 4 years of the Blue Cross Blue Shield of Massachusetts Alternative Quality Contract (AQC). METHODS We compared spending and quality among enrollees whose physician organizations entered the AQC from 2009 through 2012 with those among persons in control states. We studied spending changes according to year, category of service, site of care, experience managing risk contracts, and price versus utilization. We evaluated process and outcome quality. RESULTS In the 2009 AQC cohort, medical spending on claims grew an average of $62.21 per enrollee per quarter less than it did in the control cohort over the 4-year period (P<0.001). This amount is equivalent to a 6.8% savings when calculated as a proportion of the average post-AQC spending level in the 2009 AQC cohort. Analogously, the 2010, 2011, and 2012 cohorts had average savings of 8.8% (P<0.001), 9.1% (P<0.001), and 5.8% (P = 0.04), respectively, by the end of 2012. Claims savings were concentrated in the outpatient-facility setting and in procedures, imaging, and tests, explained by both reduced prices and reduced utilization. Claims savings were exceeded by incentive payments to providers during the period from 2009 through 2011 but exceeded incentive payments in 2012, generating net savings. Improvements in quality among AQC cohorts generally exceeded those seen elsewhere in New England and nationally. CONCLUSIONS As compared with similar populations in other states, Massachusetts AQC enrollees had lower spending growth and generally greater quality improvements after 4 years. Although other factors in Massachusetts may have contributed, particularly in the later part of the study period, global budget contracts with quality incentives may encourage changes in practice patterns that help reduce spending and improve quality. (Funded by the Commonwealth Fund and others.) PMID:25354104
Nucleon and deuteron scattering cross sections from 25 MV/Nucleon to 22.5 GeV/Nucleon
NASA Technical Reports Server (NTRS)
Townsend, L. W.; Wilson, J. W.; Bidasaria, H. B.
1983-01-01
Within the context of a double-folding optical potential approximation to the exact nucleus-nucleus multiple-scattering series, eikonal scattering theory is used to generate tables of nucleon and deuteron total and absorption cross sections at kinetic energies between 25 MeV/nucleon and 22.5 GeV/nucleon for use in cosmic-ray transport and shielding studies. Comparisons of predictions for nucleon-nucleus and deuteron-nucleus absorption and total cross sections with experimental data are also made.
Differential Cross Sections for Proton-Proton Elastic Scattering
NASA Technical Reports Server (NTRS)
Norman, Ryan B.; Dick, Frank; Norbury, John W.; Blattnig, Steve R.
2009-01-01
Proton-proton elastic scattering is investigated within the framework of the one pion exchange model in an attempt to model nucleon-nucleon interactions spanning the large range of energies important to cosmic ray shielding. A quantum field theoretic calculation is used to compute both differential and total cross sections. A scalar theory is then presented and compared to the one pion exchange model. The theoretical cross sections are compared to proton-proton scattering data to determine the validity of the models.
NASA Technical Reports Server (NTRS)
Townsend, Lawrence W.; Tripathi, Ram K.; Khan, Ferdous
1993-01-01
Cross-section predictions with semi-empirical nuclear fragmentation models from the Langley Research Center and the Naval Research Laboratory are compared with experimental data for the breakup of relativistic iron and argon projectile nuclei in various targets. Both these models are commonly used to provide fragmentation cross-section inputs into galactic cosmic ray transport codes for shielding and exposure analyses. Overall, the Langley model appears to yield better agreement with the experimental data.
2002-03-06
STS109-322-028 (6 March 2002) --- Astronaut Richard M. Linnehan, STS-109 mission specialist, participates in the third of five space walks to perform work on the Hubble Space Telescope (HST). Linnehan's sun shield reflects astronaut John M. Grunsfeld and the blue and white Earth's hemisphere as well as one of the telescope's new solar arrays. The third overall STS-109 extravehicular activity (EVA) marked the second of three for Linnehan and Grunsfeld, payload commander. On this particular walk, the two turned off the telescope in order to replace the power control unit or PCU--the heart of its power system. Grunsfeld took this photo with a 35mm camera.
Su, Jing; Sun, Yuan-Qiang; Huo, Fang-Jun; Yang, Yu-Tao; Yin, Cai-Xia
2010-11-01
A novel strategy for the determination of oxalate anions was successfully established using a copper ion and pyrocatechol violet (PV) ensemble. The sensor ensemble can discriminate oxalate over other common anions including F(-), Cl(-), I(-), Br(-), HPO(4)(2-), PO(4)(3-), AcO(-), CO(3)(2-), SO(4)(2-), ClO(4)(-), P(2)O(7)(4-), S(2-) (deposited by Ag(+)), CN(-) (shielded by Fe(3+)) and can detect oxalate at low microgram levels in quasi-physiological aqueous solutions. The detection of the oxalate anion gives rise to a rapid observable visual color change from blue to yellow.
A New Equivalence Theory Method for Treating Doubly Heterogeneous Fuel - II. Verifications
Choi, Sooyoung; Kong, Chidong; Lee, Deokjung; ...
2015-03-09
A new methodology has been developed recently to treat resonance self-shielding in systems for which the fuel compact region of a reactor lattice consists of small fuel grains dispersed in a graphite matrix. The theoretical development adopts equivalence theory in both micro- and macro-level heterogeneities to provide approximate analytical expressions for the shielded cross sections, which may be interpolated from a table of resonance integrals or Bondarenko factors using a modified background cross section as the interpolation parameter. This paper describes the first implementation of the theoretical equations in a reactor analysis code. In order to reduce discrepancies caused bymore » use of the rational approximation for collision probabilities in the original derivation, a new formulation for a doubly heterogeneous Bell factor is developed in this paper to improve the accuracy of doubly heterogeneous expressions. This methodology is applied to a wide range of pin cell and assembly test problems with varying geometry parameters, material compositions, and temperatures, and the results are compared with continuous-energy Monte Carlo simulations to establish the accuracy and range of applicability of the new approach. It is shown that the new doubly heterogeneous self-shielding method including the Bell factor correction gives good agreement with reference Monte Carlo results.« less
Radiation health for a Mars mission
NASA Technical Reports Server (NTRS)
Robbins, Donald E.
1992-01-01
Uncertainties in risk assessments for exposure of a Mars mission crew to space radiation place limitations on mission design and operation. Large shielding penalties are imposed in order to obtain acceptable safety margins. Galactic cosmic rays (GCR) and solar particle events (SPE) are the major concern. A warning system and 'safe-haven' are needed to protect the crew from large SPE which produce lethal doses. A model developed at NASA Johnson Space Center (JSC) to describe solar modulation of GCR intensities reduces that uncertainty to less than 10 percent. Radiation transport models used to design spacecraft shielding have large uncertainties in nuclear fragmentation cross sections for GCR which interact with spacecraft materials. Planned space measurements of linear energy transfer (LET) spectra behind various shielding thicknesses will reduce uncertainties in dose-versus-shielding thickness relationships to 5-10 percent. The largest remaining uncertainty is in biological effects of space radiation. Data on effects of energetic ions in human are nonexistent. Experimental research on effects in animals and cell is needed to allow extrapolation to the risk of carcinogenesis in humans.
NASA Technical Reports Server (NTRS)
Harvey, W. D.
1975-01-01
Results are presented of a coordinated experimental and theoretical study of a sound shield concept which aims to provide a means of noise reduction in the test section of supersonic wind tunnels at high Reynolds numbers. The model used consists of a planar array of circular rods aligned with the flow, with adjustable gaps between them for boundary layer removal by suction, i.e., laminar flow control. One of the basic requirements of the present sound shield concept is to achieve sonic cross flow through the gaps in order to prevent lee-side flow disturbances from penetrating back into the shielded region. Tests were conducted at Mach 6 over a local unit Reynolds number range from about 1.2 x 10 to the 6th power to 13.5 x 10 to the 6th power per foot. Measurements of heat transfer, static pressure, and sound levels were made to establish the transition characteristics of the boundary layer on the rod array and the sound shielding effectiveness.
Gamma rays shielding parameters for white metal alloys
NASA Astrophysics Data System (ADS)
Kaur, Taranjot; Sharma, Jeewan; Singh, Tejbir
2018-05-01
In the present study, an attempt has been made to check the feasibility of white metal alloys as gamma rays shielding materials. Different combinations of cadmium, lead, tin and zinc were used to prepare quaternary alloys Pb60Sn20ZnxCd20-x (where x = 5, 10, 15) using melt quench technique. These alloys were also known as white metal alloys because of its shining appearance. The density of prepared alloys has been measured using Archimedes Principle. Gamma rays shielding parameters viz. mass attenuation coefficient (µm), effective atomic number (Zeff), electron density (Nel), Mean free path (mfp), Half value layer (HVL) and Tenth value layer (TVL) has been evaluated for these alloys in the wide energy range from 1 keV to 100 GeV. The WinXCom software has been used for obtaining mass attenuation coefficient values for the prepared alloys in the given energy range. The effective atomic number (Zeff) has been assigned to prepared alloys using atomic to electronic cross section ratio method. Further, the variation of various shielding parameters with photon energy has been investigated for the prepared white metal alloys.
A Deterministic Transport Code for Space Environment Electrons
NASA Technical Reports Server (NTRS)
Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamczyk, Anne M.
2010-01-01
A deterministic computational procedure has been developed to describe transport of space environment electrons in various shield media. This code is an upgrade and extension of an earlier electron code. Whereas the former code was formulated on the basis of parametric functions derived from limited laboratory data, the present code utilizes well established theoretical representations to describe the relevant interactions and transport processes. The shield material specification has been made more general, as have the pertinent cross sections. A combined mean free path and average trajectory approach has been used in the transport formalism. Comparisons with Monte Carlo calculations are presented.
Calculations of cosmic-ray helium transport in shielding materials
NASA Technical Reports Server (NTRS)
Cucinotta, Francis A.
1993-01-01
The transport of galactic cosmic-ray helium nuclei and their secondaries through bulk shielding is considered using the straight-ahead approximation to the Boltzmann equation. A data base for nuclear interaction cross sections and secondary particle energy spectra for high-energy light-ion breakup is presented. The importance of the light ions H-2, H-3, and He-3 for cosmic-ray risk estimation is discussed, and the estimates of the fractional contribution to the neutron flux from helium interactions compared with other particle interactions are presented using a 1977 solar minimum cosmic-ray spectrum.
New Methodologies for Generation of Multigroup Cross Sections for Shielding Applications
NASA Astrophysics Data System (ADS)
Arzu Alpan, F.; Haghighat, Alireza
2003-06-01
Coupled neutron and gamma multigroup (broad-group) libraries used for Light Water Reactor shielding and dosimetry commonly include 47-neutron and 20-gamma groups. These libraries are derived from the 199-neutron, 42-gamma fine-group VITAMIN-B6 library. In this paper, we introduce modifications to the generation procedure of the broad-group libraries. Among these modifications, we show that the fine-group structure and collapsing technique have the largest impact. We demonstrate that a more refined fine-group library and the bi-linear adjoint weighting collapsing technique can improve the accuracy of transport calculation results.
Divertor for use in fusion reactors
Christensen, Uffe R.
1979-01-01
A poloidal divertor for a toroidal plasma column ring having a set of poloidal coils co-axial with the plasma ring for providing a space for a thick shielding blanket close to the plasma along the entire length of the plasma ring cross section and all the way around the axis of rotation of the plasma ring. The poloidal coils of this invention also provide a stagnation point on the inside of the toroidal plasma column ring, gently curving field lines for vertical stability, an initial plasma current, and the shaping of the field lines of a separatrix up and around the shielding blanket.
Workshop on a Cross Section of Archean Crust
NASA Technical Reports Server (NTRS)
Ashwal, L. D. (Editor); Card, K. D. (Editor)
1983-01-01
Various topics relevant to crustal genesis, especially the relationship between Archean low - and high-grade terrains, were discussed. The central Superior Province of the Canadian Shield was studied. Here a 120 km-wide transition from subgreenschist facies rocks of the Michipicoten greenstone belt to granulite facies rocks of the Kapuskasing structural zone represents an oblique cross section through some 20 km of crust, uplifted along a northwest-dipping thrust fault.
Influence of magnetite, ilmenite and boron carbide on radiation attenuation of polyester composites
NASA Astrophysics Data System (ADS)
El-Sarraf, M. A.; El-Sayed Abdo, A.
2013-07-01
This work is concerned with studying polyester/ magnetite CUP/Mag (ρ=2.75 g cm-3) and polyester/ ilmenite CUP/Ilm (ρ=2.7 g cm-3) composites for shielding of medical facilities, laboratory hot cells and for various purposes. Mechanical and physical properties such as compressive, flexural and impact strengths, as well as, a.c. electrical conductivity, specific heat, water absorption and porosity have been performed to evaluate the composite capabilities for radiation shielding. A collimated beam from fission 252Cf (100 µg) neutron source and neutron-gamma spectrometer with stilbene scintillator based on the zero cross over method and pulse shape discrimination (P.S.D.) technique have been used to measure neutron and gamma ray spectra. Fluxes of thermal neutrons have been measured using the BF3 detector and thermal neutron detection system. The attenuation parameters, namely macroscopic effective removal cross-section ΣR, total attenuation coefficient µ and macroscopic cross-section Σ of fast neutrons, gamma rays and thermal neutrons respectively have been evaluated. Theoretical calculations using MCNP-4C2 code was used to calculate ΣR,μ and Σ. Also, MERCSF-N program was used to calculate macroscopic effective removal cross-section ΣR. Measured and calculated results were compared and reasonable agreement was found.
A cargo inspection system based on pulsed fast neutron analysis (PFNA).
Ipe, N E; Olsher, R; Ryge, P; Mrozack, J; Thieu, J
2005-01-01
A cargo inspection system based on pulsed fast neutron analysis (PFNA) is to be used at a border crossing to detect explosives and contraband hidden in trucks and cargo containers. Neutrons are produced by the interaction of deuterons in a deuterium target mounted on a moveable scan arm. The collimated pulsed fast neutron beam is used to determine the location and composition of objects in a cargo container. The neutrons produce secondary gamma rays that are characteristic of the object's elemental composition. The cargo inspection system building consists of an accelerator room and an inspection tunnel. The accelerator room is shielded and houses the injector, accelerator and the neutron production gas target. The inspection tunnel is partially shielded. The truck or container to be inspected will be moved through the inspection tunnel by a conveyor system. The facility and radiation source terms considered in the shielding design are described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hong, Woo-Pyo; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr
2014-08-01
The influence of nonthermal shielding on the optically allowed and forbidden anti-screening channels for ion-ion collisional excitations is investigated in astrophysical Lorentzian plasmas. The semiclassical trajectory method and effective interaction Hamiltonian are employed to obtain the transition amplitudes, differential cross-sections, and momentum transfer-dependent effective projectile charges for the optically allowed and forbidden excitation channels as functions of the impact parameter, collision energy, Debye radius, and spectral index of nonthermal astrophysical plasmas. It is found that the nonthermal effect suppresses the ion-ion collisional excitation probability in astrophysical Lorentzian plasmas. Additionally, the influence of nonthermal shielding on the optically allowed transition ismore » found to be more significant than that on the optically forbidden transition. The variations of the nonthermal shielding effects on the optically allowed and forbidden anti-screening channels in astrophysical nonthermal plasmas are also discussed.« less
Investigation of Natural and Man-Made Radiation Effects on Crews on Long Duration Space Missions
NASA Technical Reports Server (NTRS)
Bolch, Wesley E.; Parlos, Alexander
1996-01-01
Over the past several years, NASA has studied a variety of mission scenarios designed to establish a permanent human presence on the surface of Mars. Nuclear electric propulsion (NEP) is one of the possible elements in this program. During the initial stages of vehicle design work, careful consideration must be given to not only the shielding requirements of natural space radiation, but to the shielding and configuration requirements of the on-board reactors. In this work, the radiation transport code MCNP has been used to make initial estimates of crew exposures to reactor radiation fields for a specific manned NEP vehicle design. In this design, three 25 MW(sub th), scaled SP-100-class reactors are shielded by three identical shields. Each shield has layers of beryllium, tungsten, and lithium hydride between the reactor and the crew compartment. Separate calculations are made of both the exiting neutron and gamma fluxes from the reactors during beginning-of-life, full-power operation. This data is then used as the source terms for particle transport in MCNP. The total gamma and neutron fluxes exiting the reactor shields are recorded and separate transport calculations are then performed for a 10 g/sq cm crew compartment aluminum thickness. Estimates of crew exposures have been assessed for various thicknesses of the shield tungsten and lithium hydride layers. A minimal tungsten thickness of 20 cm is required to shield the reactor photons below the 0.05 Sv/y man-made radiation limit. In addition to a 20-cm thick tungsten layer, a 40-cm thick lithium hydride layer is required to shield the reactor neutrons below the annual limit. If the tungsten layer is 30-cm thick, the lithium hydride layer should be at least 30-cm thick. These estimates do not take into account the photons generated by neutron interactions inside the shield because the MCNP neutron cross sections did not allow reliable estimates of photon production in these materials. These results, along with natural space radiation shielding estimates calculated by NASA Langley Research Center, have been used to provide preliminary input data into a new Macintosh-based software tool. A skeletal version of this tool being developed will allow rapid radiation exposure and risk analyses to be performed on a variety of Lunar and Mars missions utilizing nuclear-powered vehicles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, Y; Nyblade, A; Rodgers, A
2007-11-09
The shear velocity structure of the shallow upper mantle beneath the Arabian Shield has been modeled by inverting new Rayleigh wave phase velocity measurements between 45 and 140 s together with previously published Rayleigh wave group velocity measurement between 10 and 45 s. For measuring phase velocities, we applied a modified array method that minimizes the distortion of raypaths by lateral heterogeneity. The new shear velocity model shows a broad low velocity region in the lithospheric mantle across the Shield and a low velocity region at depths {ge} 150 km localized along the Red Sea coast and Makkah-Madinah-Nafud (MMN) volcanicmore » line. The velocity reduction in the upper mantle corresponds to a temperature anomaly of {approx}250-330 K. These finding, in particular the region of continuous low velocities along the Red Sea and MMN volcanic line, do not support interpretations for the origin of the Cenozoic plateau uplift and volcanism on the Shield invoking two separate plumes. When combined with images of the 410 and 660 km discontinuities beneath the southern part of the Arabian Shield, body wave tomographic models, a S-wave polarization analysis, and SKS splitting results, our new model supports an interpretation invoking a thermal upwelling of warm mantle rock originating in the lower mantle under Africa that crosses through the transition zone beneath Ethiopia and moves to the north and northwest under the eastern margin of the Red Sea and the Arabian Shield. In this interpretation, the difference in mean elevation between the Platform and Shield can be attributed to isostatic uplift caused by heating of the lithospheric mantle under the Shield, with significantly higher region along the Red Sea possibly resulting from a combination of lithosphere thinning and dynamic uplift.« less
Photodissociation and photoionisation of atoms and molecules of astrophysical interest
NASA Astrophysics Data System (ADS)
Heays, A. N.; Bosman, A. D.; van Dishoeck, E. F.
2017-06-01
A new collection of photodissociation and photoionisation cross sections for 102 atoms and molecules of astrochemical interest has been assembled, along with a brief review of the basic physical processes involved. These have been used to calculate dissociation and ionisation rates, with uncertainties, in a standard ultraviolet interstellar radiation field (ISRF) and for other wavelength-dependent radiation fields, including cool stellar and solar radiation, Lyman-α dominated radiation, and a cosmic-ray induced ultraviolet flux. The new ISRF rates generally agree within 30% with our previous compilations, with a few notable exceptions. Comparison with other databases such as PHIDRATES is made. The reduction of rates in shielded regions was calculated as a function of dust, molecular and atomic hydrogen, atomic C, and self-shielding column densities. The relative importance of these shielding types depends on the atom or molecule in question and the assumed dust optical properties. All of the new data are publicly available from the Leiden photodissociation and ionisation database. Sensitivity of the calculated rates to variation of temperature and isotope, and uncertainties in measured or calculated cross sections, are tested and discussed. Tests were conducted on the new rates with an interstellar-cloud chemical model, and find general agreement (within a factor of two) in abundances obtained with the previous iteration of the Leiden database assuming an ISRF, and order-of-magnitude variations assuming various kinds of stellar radiation. The newly parameterised dust-shielding factors makes a factor-of-two difference to many atomic and molecular abundances relative to parameters currently in the UDfA and KIDA astrochemical reaction databases. The newly-calculated cosmic-ray induced photodissociation and ionisation rates differ from current standard values up to a factor of 5. Under high temperature and cosmic-ray-flux conditions the new rates alter the equilibrium abundances of abundant dark cloud abundances by up to a factor of two. The partial cross sections for H2O and NH3 photodissociation forming OH, O, NH2 and NH are also evaluated and lead to radiation-field-dependent branching ratios.
Visual light effects on mitochondria: The potential implications in relation to glaucoma.
Osborne, Neville N; Núñez-Álvarez, Claudia; Del Olmo-Aguado, Susana; Merrayo-Lloves, Jesús
2017-09-01
Light of different wave-lengths have the potential to interact with four major mitochondrial protein complexes that are involved in the generation of ATP. Neurones of the central nervous system have an absolute dependence on mitochondrial generated ATP. Laboratory studies show that short-wave or blue light (400-480nm) that impinges on the retina affect flavin and cytochrome constituents associated with mitochondria to decrease the rate of ATP formation, stimulate ROS and results in cell death. This suggests that blue light could potentially have a negative influence on retinal ganglion cell (RGC) mitochondria that are abundant and not shielded by macular pigments as occurs for photoreceptor mitochondria. This might be of significance in glaucoma where it is likely that RGC mitochondria are already affected and therefore be more susceptible to blue light. Thus simply filtering out some natural blue light from entering the eye might be beneficial for the treatment of glaucoma. Long-wave or red light (650-800nm) affects mitochondrial complex IV or cytochrome oxidase to increase the rate of formation of ATP and ROS causing the generation of a number of beneficial factors. Significantly, laboratory studies show that increasing the normal amount of natural red light reaching rat RGC mitochondria in situ, subjected to ischemia, proved to be beneficial. A challenge now is to test whether extra red light delivered to the human retina can slow-down RGC loss in glaucoma. Such a methodology has also the advantage of being non-invasive. One very exciting possibility might be in the production of a lens where solar UV light is convertes to add to the amount of natural red light entering the eye. Copyright © 2016 Elsevier B.V. and Mitochondria Research Society. All rights reserved.
Tables of nuclear cross sections for galactic cosmic rays: Absorption cross sections
NASA Technical Reports Server (NTRS)
Townsend, L. W.; Wilson, J. W.
1985-01-01
A simple but comprehensive theory of nuclear reactions is presented. Extensive tables of nucleon, deuteron, and heavy-ion absorption cross sections over a broad range of energies are generated for use in cosmic ray shielding studies. Numerous comparisons of the calculated values with available experimental data show agreement to within 3 percent for energies above 80 MeV/nucleon and within approximately 10 percent for energies as low as 30 MeV/nucleon. These tables represent the culmination of the development of the absorption cross section formalism and supersede the preliminary absorption cross sections published previously in NASA TN D-8107, NASA TP-2138, and NASA TM-84636.
Heo, Jung-Yoon; Kim, Kiwon; Fava, Maurizio; Mischoulon, David; Papakostas, George I; Kim, Min-Ji; Kim, Dong Jun; Chang, Kyung-Ah Judy; Oh, Yunhye; Yu, Bum-Hee; Jeon, Hong Jin
2017-04-01
Smartphones deliver light to users through Light Emitting Diode (LED) displays. Blue light is the most potent wavelength for sleep and mood. This study investigated the immediate effects of smartphone blue light LED on humans at night. We investigated changes in serum melatonin levels, cortisol levels, body temperature, and psychiatric measures with a randomized, double-blind, cross-over, placebo-controlled design of two 3-day admissions. Each subject played smartphone games with either conventional LED or suppressed blue light from 7:30 to 10:00PM (150 min). Then, they were readmitted and conducted the same procedure with the other type of smartphone. Serum melatonin levels were measured in 60-min intervals before, during and after use of the smartphones. Serum cortisol levels and body temperature were monitored every 120 min. The Profile of Mood States (POMS), Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), and auditory and visual Continuous Performance Tests (CPTs) were administered. Among the 22 participants who were each admitted twice, use of blue light smartphones was associated with significantly decreased sleepiness (Cohen's d = 0.49, Z = 43.50, p = 0.04) and confusion-bewilderment (Cohen's d = 0.53, Z = 39.00, p = 0.02), and increased commission error (Cohen's d = -0.59, t = -2.64, p = 0.02). Also, users of blue light smartphones experienced a longer time to reach dim light melatonin onset 50% (2.94 vs. 2.70 h) and had increases in body temperature, serum melatonin levels, and cortisol levels, although these changes were not statistically significant. Use of blue light LED smartphones at night may negatively influence sleep and commission errors, while it may not be enough to lead to significant changes in serum melatonin and cortisol levels. Copyright © 2016 Elsevier Ltd. All rights reserved.
Electrodynamic Dust Shield for Space Applications
NASA Technical Reports Server (NTRS)
Mackey, P. J.; Johansen, M. R.; Olsen, R. C.; Raines, M. G.; Phillips, J. R., III; Pollard, J. R. S.; Calle, C. I.
2016-01-01
The International Space Exploration Coordination Group (ISECG) has chosen dust mitigation technology as a Global Exploration Roadmap (GER) critical technology need in order to reduce life cycle cost and risk, and increase the probability of mission success. NASA has also included Particulate Contamination Prevention and Mitigation as a cross-cutting technology to be developed for contamination prevention, cleaning and protection. This technology has been highlighted due to the detrimental effect of dust on both human and robotic missions. During manned Apollo missions, dust caused issues with both equipment and crew. Contamination of equipment caused many issues including incorrect instrument readings and increased temperatures due to masking of thermal radiators. The astronauts were directly affected by dust that covered space suits, obscured face shields and later propagated to the cabin and into the crew's eyes and lungs. Robotic missions on Mars were affected when solar panels were obscured by dust thereby reducing the effectiveness of the solar panels. The Electrostatics and Surface Physics Lab in Swamp Works at the Kennedy Space Center has been developing an Electrodynamic Dust Shield (EDS) to remove dust from multiple surfaces, including glass shields and thermal radiators. This technology has been tested in lab environments and has evolved over several years. Tests of the technology include reduced gravity flights (one-sixth g) in which Apollo Lunar dust samples were successfully removed from glass shields while under vacuum (10(exp -6) kPa).
Gamma-ray shielding effect of Gd3+ doped lead barium borate glasses
NASA Astrophysics Data System (ADS)
Kummathi, Harshitha; Naveen Kumar, P.; Vedavathi T., C.; Abhiram, J.; Rajaramakrishna, R.
2018-05-01
The glasses of the batch xPbO: 10BaO: (90-x)B2O3: 0.2Gd2O3 (x = 40,45,50 mol %) were prepared by melt-quench technique. The work emphasizes on gamma ray shielding effect on doped lead glasses. The role of Boron is significant as it acts as better neutron attenuator as compared with any other materials, as the thermal neutron cross-sections are high for Gadolinium, 0.2 mol% is chosen as the optimum concentration for this matrix, as higher the concentration may lead to further increase as it produces secondary γ rays due to inelastic neutron scattering. Shielding effects were studied using Sodium Iodide (NaI) - Scintillation Gamma ray spectrometer. It was found that at higher concentration of lead oxide (PbO) in the matrix, higher the attenuation which can be co-related with density. Infra-red (I.R.) spectra reveals that the conversion of Lose triangles to tight tetrahedral structure results in enhancement of shielding properties. The Differential Scanning Calorimeter (D.S.C.) study also reveals that the increase in glass forming range increases the stability which in-turn results in inter-conversion of BO3 to BO4 units such that the density of glass increases with increase in PbO content, resulting in much stable and efficient gamma ray shielding glasses.
HZETRN: Description of a free-space ion and nucleon transport and shielding computer program
NASA Technical Reports Server (NTRS)
Wilson, John W.; Badavi, Francis F.; Cucinotta, Francis A.; Shinn, Judy L.; Badhwar, Gautam D.; Silberberg, R.; Tsao, C. H.; Townsend, Lawrence W.; Tripathi, Ram K.
1995-01-01
The high-charge-and energy (HZE) transport computer program HZETRN is developed to address the problems of free-space radiation transport and shielding. The HZETRN program is intended specifically for the design engineer who is interested in obtaining fast and accurate dosimetric information for the design and construction of space modules and devices. The program is based on a one-dimensional space-marching formulation of the Boltzmann transport equation with a straight-ahead approximation. The effect of the long-range Coulomb force and electron interaction is treated as a continuous slowing-down process. Atomic (electronic) stopping power coefficients with energies above a few A MeV are calculated by using Bethe's theory including Bragg's rule, Ziegler's shell corrections, and effective charge. Nuclear absorption cross sections are obtained from fits to quantum calculations and total cross sections are obtained with a Ramsauer formalism. Nuclear fragmentation cross sections are calculated with a semiempirical abrasion-ablation fragmentation model. The relation of the final computer code to the Boltzmann equation is discussed in the context of simplifying assumptions. A detailed description of the flow of the computer code, input requirements, sample output, and compatibility requirements for non-VAX platforms are provided.
NASA Astrophysics Data System (ADS)
Horvath, Ildiko; Lovell, Brian C.
2018-02-01
This study investigates two recently reported subauroral phenomena: the abnormal subauroral ion drift (ASAID) appearing as an inverted SAID and the shielding-E—SAID structure depicting a SAID feature on the poleward side of a small eastward or antisunward flow channel that is the shielding electric (E) field's signature. We have analyzed polar cross sections, constructed with multi-instrument Defense Meteorological Satellite Program data, for the development of these subauroral phenomena. New results show the features of abnormal subauroral polarization stream (ASAPS) and ASAID-ASAPS comprised by a narrow ASAID embedded in a wider ASAPS. We have identified undershielding, perfect shielding, and overshielding events. Our observational results demonstrate SAPS development during undershielding, the absence of subauroral flow channel during perfect shielding, and ASAID/ASAPS and shielding-E—SAID/SAPS development during overshielding. The appearance of an ASAID-ASAPS structure together with a pair of dayside-nightside eastward auroral flow channels implies the intensification of region 2 field-aligned currents via the westward traveling surge and thus the strengthening of overshielding conditions. From the observational results presented we conclude for the magnetically active time period studied that (i) the shielding E field drove the wider ASAPS flow channel, (ii) the ASAID-ASAPS structure's narrow antisunward flow channel developed due to the injections of hot ring current ions in a short-circuited system wherein the hot ring current plasma was closer to the Earth than the cold plasmaspheric plasma, and (iii) overshielding created this hot-cold plasma configuration via the development of a plasmaspheric shoulder.
Root-shoot interaction in the greening of wheat seedlings grown under red light
NASA Technical Reports Server (NTRS)
Tripathy, B. C.; Brown, C. S.
1995-01-01
Wheat seedlings grown with roots exposed to constant red light (300-500 micromoles m-2 s-1) did not accumulate chlorophyll in the leaves. In contrast, seedlings grown with their roots shielded from light accumulated chlorophylls. Chlorophyll biosynthesis could be induced in red-light-grown chlorophyll-deficient yellow plants by either reducing the red-light intensity at the root surface to 100 micromoles m-1 s-1 or supplementing with 6% blue light. The inhibition of chlorophyll biosynthesis was due to impairment of the Mg-chelatase enzyme working at the origin of the Mg-tetrapyrrole pathway. The root-perceived photomorphogenic inhibition of shoot greening demonstrates root-shoot interaction in the greening process.
NASA Technical Reports Server (NTRS)
1986-01-01
The tectonic evaluation of the Nubian Shield using the Thematic Mapper (TM) imagery is progressing well and shows great promise. The TM tapes for the six LANDSAT 5 scenes covering the northern portion of the Red Sea hills were received, and preliminary maps and interpretations were made for most of the area. It is apparent that faulting and shearing associated with the major suture zones such as the Sol Hamed are clearly visible and that considerable detail can be seen. An entire quadrant of scene 173,45 was examined in detail using all seven bands, and every band combination was evaluated to best display the geology. A comparison was done with color ratio combinations and color combinations of the eigen vector bands to verify if band combinations of 7-red, 4-green, and 2-blue were indeed superior. There is no single optimum enhancement which provides the greatest detail for every image and no single combination of spectral bands for all cases, although bands 7, 4, and 2 do provide the best overall display. The color combination of the eigen vector bands proved useful in distinguishing fine detailed features.
Chen, Xiaoqiang; Song, Wei; Zhao, Jin; Zhang, Zhifa; Zhang, Yuntian
2017-05-31
Polysaccharide conjugates were alkali-extracted from green tea (TPC-A). Although it contained 11.80% covalently binding proteins, TPC-A could not bind to the Coomassie Brilliant Blue dyes G250 and R250. TPC-A had no expected characteristic absorption peak of protein in the UV-vis spectrum scanning in the range of 200-700 nm. The UV-vis wavelength of 280 nm was not suitable to detect the presence of the protein portion of TPC-A. The zeta potential of TPC-A merely presented the negative charge properties of polysaccharides instead of the acid-base property of its protein section across the entire pH range. Furthermore, TPC-A was more stable when the pH of solution exceeded 4.0. In addition, no precipitation or haze was generated in the TPC-A/(-)-epigallocatechin gallate (EGCG) mixtures during 12 h storage. TPC-A has emulsifying activity, which indicated that its protein moiety formed hydrophobic groups. Thus, it was proposed that some physical properties of TPC-A protein were shielded by its olysaccharide, since the protein moiety was wrapped by its polysaccharide chains.
NASA Astrophysics Data System (ADS)
Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela
2017-09-01
The ENEA-Bologna Nuclear Data Group produced the VITJEFF32.BOLIB multi-group coupled neutron/photon (199 n + 42 γ) cross section library in AMPX format, based on the OECD-NEA Data Bank JEFF-3.2 evaluated nuclear data library. VITJEFF32.BOLIB was conceived for nuclear fission applications as European counterpart of the ORNL VITAMIN-B7 similar library (ENDF/B-VII.0 data). VITJEFF32.BOLIB has the same neutron and photon energy group structure as the former ORNL VITAMIN-B6 reference library (ENDF/B-VI.3 data) and was produced using similar data processing methodologies, based on the LANL NJOY-2012.53 nuclear data processing system for the generation of the nuclide cross section data files in GENDF format. Then the ENEA-Bologna 2007 Revision of the ORNL SCAMPI nuclear data processing system was used for the conversion into the AMPX format. VITJEFF32.BOLIB contains processed cross section data files for 190 nuclides, obtained through the Bondarenko (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the ORNL DOORS system, can be generated from VITJEFF32.BOLIB through the cited SCAMPI version. This paper describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF32.BOLIB validation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wright, R.Q.; Renier, J.P.; Bucholz, J.A.
1995-08-01
The original ANSL-V cross-section libraries (ORNL-6618) were developed over a period of several years for the physics analysis of the ANS reactor, with little thought toward including the materials commonly needed for shielding applications. Materials commonly used for shielding applications include calcium barium, sulfur, phosphorous, and bismuth. These materials, as well as {sup 6}Li, {sup 7}Li, and the naturally occurring isotopes of hafnium, have been added to the ANSL-V libraries. The gamma-ray production and gamma-ray interaction cross sections were completely regenerated for the ANSL-V 99n/44g library which did not exist previously. The MALOCS module was used to collapse the 99n/44gmore » coupled library to the 39n/44g broad- group library. COMET was used to renormalize the two-dimensional (2- D) neutron matrix sums to agree with the one-dimensional (1-D) averaged values. The FRESH module was used to adjust the thermal scattering matrices on the 99n/44g and 39n/44g ANSL-V libraries. PERFUME was used to correct the original XLACS Legendre polynomial fits to produce acceptable distributions. The final ANSL-V 99n/44g and 39n/44g cross-section libraries were both checked by running RADE. The AIM module was used to convert the master cross-section libraries from binary coded decimal to binary format (or vice versa).« less
Nuclear fragmentation of GCR-like ions: comparisons between data and PHITS
NASA Astrophysics Data System (ADS)
Zeitlin, Cary; Guetersloh, Stephen; Heilbronn, Lawrence; Miller, Jack; Sihver, Lembit; Mancusi, Davide; Fukumura, Aki; Iwata, Yoshi; Murakami, Takeshi
We present a summary of results from recent work in which we have compared nuclear fragmentation cross section data to predictions of the PHITS Monte Carlo simulation. The studies used beams of 12 C, 35 Cl, 40 Ar, 48 Ti, and 56 Fe at energies ranging from 290 MeV/nucleon to 1000 MeV/nucleon. Some of the data were obtained at the Brookhaven National Laboratory, others at the National Institute of Radiological Sciences in Japan. These energies and ion species are representative of the heavy ion component of the Galactic Cosmic Rays (GCR), which contribute significantly to the dose and dose equivalent that will be received by astronauts on deep-space missions. A critical need for NASA is the ability to accurately model the transport of GCR heavy ions through matter, including spacecraft walls, equipment racks, and other shielding materials, as well as through tissue. Nuclear interaction cross sections are of primary importance in the GCR transport problem. These interactions generally cause the incoming ion to break up (fragment) into one or more lighter ions, which continue approximately along the initial trajectory and with approximately the same velocity the incoming ion had prior to the interaction. Since the radiation dose delivered by a particle is proportional to the square of the quantity (charge/velocity), i.e., to (Z/β)2 , fragmentation reduces the dose (and, typically, dose equivalent) delivered by incident ions. The other mechanism by which dose can be reduced is ionization energy loss, which can lead to some particles stopping in the shielding. This is the conventional notion of shielding, but it is not applicable to human spaceflight, since the particles in the GCR tend to be highly energetic and because shielding must be relatively thin in order to keep overall mass as low as possible, keeping launch costs within reason. To support these goals, our group has systematically measured a large number of nuclear cross sections, intended to be used as either input to, or validation of, NASA transport models. A database containing over 200 charge-changing cross sections, and over 2000 fragment production cross sections, is nearing completion, with most results available online. In the past year, we have been investigating the PHITS (Particle and Heavy Ion Transport System) model of Niita et al. For purposes of modeling nuclear interactions, PHITS combines the Jet AA Microscopic Transport Model (JAM) hadron cascade model, the Jaeri Quantum Molecular Dynamics (JQMD) model, and the Generalized Evaporation Model (GEM). We will present detailed comparisons of our data to the cross sections and fragment angular distributions that arise from this model. The model contains some significant deficiencies, but, as we will show, also represents a significant advance over older, simpler models of fragmentation. 504b030414000600080000002100828abc13fa0000001c020000130000005b436f6e74656e745f54797065735d2e78
Development of deterministic transport methods for low energy neutrons for shielding in space
NASA Technical Reports Server (NTRS)
Ganapol, Barry
1993-01-01
Transport of low energy neutrons associated with the galactic cosmic ray cascade is analyzed in this dissertation. A benchmark quality analytical algorithm is demonstrated for use with BRYNTRN, a computer program written by the High Energy Physics Division of NASA Langley Research Center, which is used to design and analyze shielding against the radiation created by the cascade. BRYNTRN uses numerical methods to solve the integral transport equations for baryons with the straight-ahead approximation, and numerical and empirical methods to generate the interaction probabilities. The straight-ahead approximation is adequate for charged particles, but not for neutrons. As NASA Langley improves BRYNTRN to include low energy neutrons, a benchmark quality solution is needed for comparison. The neutron transport algorithm demonstrated in this dissertation uses the closed-form Green's function solution to the galactic cosmic ray cascade transport equations to generate a source of neutrons. A basis function expansion for finite heterogeneous and semi-infinite homogeneous slabs with multiple energy groups and isotropic scattering is used to generate neutron fluxes resulting from the cascade. This method, called the FN method, is used to solve the neutral particle linear Boltzmann transport equation. As a demonstration of the algorithm coded in the programs MGSLAB and MGSEMI, neutron and ion fluxes are shown for a beam of fluorine ions at 1000 MeV per nucleon incident on semi-infinite and finite aluminum slabs. Also, to demonstrate that the shielding effectiveness against the radiation from the galactic cosmic ray cascade is not directly proportional to shield thickness, a graph of transmitted total neutron scalar flux versus slab thickness is shown. A simple model based on the nuclear liquid drop assumption is used to generate cross sections for the galactic cosmic ray cascade. The ENDF/B V database is used to generate the total and scattering cross sections for neutrons in aluminum. As an external verification, the results from MGSLAB and MGSEMI were compared to ANISN/PC, a routinely used neutron transport code, showing excellent agreement. In an application to an aluminum shield, the FN method seems to generate reasonable results.
NASA Astrophysics Data System (ADS)
Ross, Ashley J.; Samushia, Lado; Burden, Angela; Percival, Will J.; Tojeiro, Rita; Manera, Marc; Beutler, Florian; Brinkmann, J.; Brownstein, Joel R.; Carnero, Aurelio; da Costa, Luiz A. N.; Eisenstein, Daniel J.; Guo, Hong; Ho, Shirley; Maia, Marcio A. G.; Montesano, Francesco; Muna, Demitri; Nichol, Robert C.; Nuza, Sebastián E.; Sánchez, Ariel G.; Schneider, Donald P.; Skibba, Ramin A.; Sobreira, Flávia; Streblyanska, Alina; Swanson, Molly E. C.; Thomas, Daniel; Tinker, Jeremy L.; Wake, David A.; Zehavi, Idit; Zhao, Gong-bo
2014-01-01
We study the clustering of galaxies, as a function of their colour, from Data Release Ten (DR10) of the Sloan Digital Sky Survey III (SDSS-III) Baryon Oscillation Spectroscopic Survey. DR10 contains 540 505 galaxies with 0.43 < z < 0.7; from these we select 122 967 for a `Blue' sample and 131 969 for a `Red' sample based on k + e corrected (to z = 0.55) r - i colours and i-band magnitudes. The samples are chosen such that both contain more than 100 000 galaxies, have similar redshift distributions and maximize the difference in clustering amplitude. The Red sample has a 40 per cent larger bias than the Blue (bRed/bBlue = 1.39 ± 0.04), implying that the Red galaxies occupy dark matter haloes with an average mass that is 0.5 log10 M⊙ greater. Spherically averaged measurements of the correlation function, ξ0, and the power spectrum are used to locate the position of the baryon acoustic oscillation (BAO) feature of both samples. Using ξ0, we obtain distance scales, relative to the distance of our reference Λ cold dark matter cosmology, of 1.010 ± 0.027 for the Red sample and 1.005 ± 0.031 for the Blue. After applying reconstruction, these measurements improve to 1.013 ± 0.020 for the Red sample and 1.008 ± 0.026 for the Blue. For each sample, measurements of ξ0 and the second multipole moment, ξ2, of the anisotropic correlation function are used to determine the rate of structure growth, parametrized by fσ8. We find fσ8, Red = 0.511 ± 0.083, fσ8, Blue = 0.509 ± 0.085 and fσ8, Cross = 0.423 ± 0.061 (from the cross-correlation between the Red and Blue samples). We use the covariance between the bias and growth measurements obtained from each sample and their cross-correlation to produce an optimally combined measurement of fσ8, comb = 0.443 ± 0.055. This result compares favourably to that of the full 0.43 < z < 0.7 sample (fσ8, full = 0.422 ± 0.051) despite the fact that, in total, we use less than half of the number of galaxies analysed in the full sample measurement. In no instance do we detect significant differences in distance scale or structure growth measurements obtained from the Blue and Red samples. Our results are consistent with theoretical predictions and our tests on mock samples, which predict that any colour-dependent systematic uncertainty on the measured BAO position is less than 0.5 per cent.
McDowell, Jeffrey J; Maier-Flaig, Florian; Wolf, Thomas J A; Unterreiner, Andreas-Neil; Lemmer, Uli; Ozin, Geoffrey
2014-01-08
Poly(silafluorene)s (PSFs) are promising light-emitting materials with brilliant solid-state blue luminescence, high quantum efficiency, excellent solubility, and improved thermal and chemical stability. PSFs are reported to have high electron affinity and conductivity originating from σ*-π* conjugation between the σ*-antibonding orbital of the exocyclic Si-C bond and the π* antibonding orbital of the butadiene fragment, a promising characteristic for improved charge carrier balance in OLEDs. In this paper, we present a protocol for photopatterning derivatives of poly(3,6-dimethoxy-9,9-dialkylsilafluorenes) with resolutions exceeding 10 μm. The procedure begins by converting polymers (Mn = 50-55 kg/mol, PDI = 1.8) with cyclohexenyl and norbornenyl containing side chains to their respective epoxides using the Prilezhaev reaction and m-chloroperoxybenzoic acid (m-CPBA). Using the I-line (365 nm) of a Karl Suss MA6 mask aligner, a 1 s UV light exposure of the photoacid generator (PAG) bis(4-tert-butylphenyl)iodonium hexafluoro-phosphate (DtBPI-PF6) generates sufficient protons to catalyze epoxide ring-opening and form a bridging network of covalent C-O bonds which renders the material insoluble in developing solvents such as toluene or THF. The resultant cross-linked material possess characteristic blue photoluminescence with solid state quantum yields >80%. Polymer films have excellent transparency (with a measured Eg ≈ 3.0 eV). Energy levels determined using cyclic voltammetry were -5.7 and -2.7 eV for HOMO and LUMO, respectively. Additionally, several device applications are demonstrated which incorporate cross-linked films. These include examples of solid state lasing in the region of 420-450 nm from cross-linked films on second order corrugated silica substrates (Λ = 200 nm). OLEDs were also prepared with a cross-linked emitting layer as part of a trilayer device which we report to have a maximum external quantum efficiency of 3.2% at 33 mA/cm(2) and a stable blue-violet emission with an electroluminescence maximum at 410 nm. Photopatternable PSF epoxides are also shown to be efficient hosts for Förster energy transfer and we provide examples of pattern layers incorporating small molecule emitters which emit in both the red and green while blue emission of the host is effectively suppressed.
Direct Evidence of Intrinsic Blue Fluorescence from Oligomeric Interfaces of Human Serum Albumin.
Bhattacharya, Arpan; Bhowmik, Soumitra; Singh, Amit K; Kodgire, Prashant; Das, Apurba K; Mukherjee, Tushar Kanti
2017-10-10
The molecular origin behind the concentration-dependent intrinsic blue fluorescence of human serum albumin (HSA) is not known yet. This unusual blue fluorescence is believed to be a characteristic feature of amyloid-like fibrils of protein/peptide and originates due to the delocalization of peptide bond electrons through the extended hydrogen bond networks of cross-β-sheet structure. Herein, by combining the results of spectroscopy, size exclusion chromatography, native gel electrophoresis, and confocal microscopy, we have shown that the intrinsic blue fluorescence of HSA exclusively originates from oligomeric interfaces devoid of any amyloid-like fibrillar structure. Our study suggests that this low energy fluorescence band is not due to any particular residue/sequence, but rather it is a common feature of self-assembled peptide bonds. The present findings of intrinsic blue fluorescence from oligomeric interfaces pave the way for future applications of this unique visual phenomenon for early stage detection of various protein aggregation related human diseases.
Veladiano, Irene A; Banzato, Tommaso; Bellini, Luca; Montani, Alessandro; Catania, Salvatore; Zotti, Alessandro
2016-12-01
OBJECTIVE To create an atlas of the normal CT anatomy of the head of blue-and-gold macaws (Ara ararauna), African grey parrots (Psittacus erithacus), and monk parakeets (Myiopsitta monachus). ANIMALS 3 blue-and-gold macaws, 5 African grey parrots, and 6 monk parakeets and cadavers of 4 adult blue-and-gold macaws, 4 adult African grey parrots, and 7 monk parakeets. PROCEDURES Contrast-enhanced CT imaging of the head of the live birds was performed with a 4-multidetector-row CT scanner. Cadaveric specimens were stored at -20°C until completely frozen, and each head was then sliced at 5-mm intervals to create reference cross sections. Frozen cross sections were cleaned with water and photographed on both sides. Anatomic structures within each head were identified with the aid of the available literature, labeled first on anatomic photographs, and then matched to and labeled on corresponding CT images. The best CT reconstruction filter, window width, and window level for obtaining diagnostic images of each structure were also identified. RESULTS Most of the clinically relevant structures of the head were identified in both the cross-sectional photographs and corresponding CT images. Optimal visibility of the bony structures was achieved via CT with a standard soft tissue filter and pulmonary window. The use of contrast medium allowed a thorough evaluation of the soft tissues. CONCLUSIONS AND CLINICAL RELEVANCE The labeled CT images and photographs of anatomic structures of the heads of common pet parrot species created in this study may be useful as an atlas to aid interpretation of images obtained with any imaging modality.
NASA Astrophysics Data System (ADS)
Lawless, Mary K.; Mathies, Richard A.
1992-06-01
Absolute resonance Raman cross sections are measured for Nile blue 690 perchlorate dissolved in ethylene glycol with excitation at 514, 531, and 568 nm. These values and the absorption spectrum are modeled using a time-dependent wave packet formalism. The excited-state equilibrium geometry changes are quantitated for 40 resonance Raman active modes, seven of which (590, 1141, 1351, 1429, 1492, 1544, and 1640 cm-1 ) carry 70% of the total resonance Raman intensity. This demonstrates that in addition to the prominent 590 and 1640 cm-1 modes, a large number of vibrational degrees of freedom are Franck-Condon coupled to the electronic transition. After exposure of the explicit vibrational progressions, the residual absorption linewidth is separated into its homogeneous [350 cm-1 half-width at half-maximum (HWHM)] and inhomogeneous (313 cm-1 HWHM) components through an analysis of the absolute Raman cross sections. The value of the electronic dephasing time derived from this study (25 fs) compares well to previously published results. These data should be valuable in multimode modeling of femtosecond experiments on Nile blue.
NASA Astrophysics Data System (ADS)
Bernard, Ethan; LZ Collaboration
2013-10-01
Astrophysical and cosmological observations show that dark matter is concentrated in halos around galaxies and is approximately five times more abundant than baryonic matter. Dark matter has evaded direct detection despite a series of increasingly sensitive experiments. The LZ (LUX-ZEPLIN) experiment will use a two-phase liquid-xenon time projection chamber to search for elastic scattering of xenon nuclei by WIMP (weakly interactive massive particle) dark matter. The detector will contain seven tons of liquid xenon shielded by an active organic scintillator veto and a water tank within the Sanford Underground Research Facility (SURF) in Lead, South Dakota. The LZ detector scales up the demonstrated light-sensing, cryogenic, radiopurity and shielding technologies of the LUX experiment. Active shielding, position fiducialization, radiopurity control and signal discrimination will reduce backgrounds to levels subdominant to solar neutrino scattering. This experiment will reach a sensitivity to the WIMP-nucleon spin-independent cross section approaching ~ 2 .10-48 cm2 for a 50 GeV WIMP mass, which is about three orders of magnitude smaller than current limits.
ARV Re-Entry Module Aerodynmics And Aerothermodynamics
NASA Astrophysics Data System (ADS)
Scheer, Heloise; Tran, Philippe; Berthe, Philippe
2011-05-01
Astrium-ST is the prime contractor of ARV phase A and is especially in charge of designing the Reentry Module (RM). The RM aeroshape has been defined following a trade-off. High level system requirements were derived with particular attention paid on minimum lift-over-drag ratio, trim incidence, centre-of-gravity lateral off-set and box size, volumetric efficiency, attitude at parachute deployment, flight heritage and aeroheating. Since moderate cross-range and thus L/D ratio were required, the aeroshape trade-off has been performed among blunt capsule candidates. Two front- shield families were considered: spherical (Apollo/ARD/Soyuz type) and sphero-conical (CTV type) segment front-shield. The rear-cone angle was set to 20° for internal pressurized volume and accommodation purposes. Figures of merit were assessed and a spherical front- shield of ARD type with a 20° rear-cone section was selected and proposed for further investigations. Maximum benefits will be taken from ARD flight heritage. CFD and WTT campaigns plans will be presented including preliminary results.
High Density Shielded MEA / Optrode Arrays
NASA Astrophysics Data System (ADS)
Naughton, Jeff; Varela, Juan M.; Christianson, John P.; Chiles, Thomas C.; Burns, Michael J.; Naughton, Michael J.
We report on the development of a novel, high density, locally-shielded neuroelectronic / optoelectronic array architecture, useful for bioelectronics and neurophysiology. The device has been used in real time to noninvasively couple to leech neurons, allowing for extracellular recording of synaptic activity in the form of spontaneous synapse firing in pre- and post-synaptic somata. In addition, we show by subtly altering the architecture the ability for optical integration with the device - that is, it can function as both a local light delivery conduit and a recording electrode. We utilized this novel device to optically elicit and electrically record membrane currents in HEK293 cells transfected with plasmids encoding ChR2-YFP (i.e. optogenetics). Finally, we show that the local (Faraday) shield is effective in isolating the sensing area, so as to record only from cells in immediate proximity. This effective isolation or cross-talk suppression is important for moving closer to ``ground truth'' measurements of neurons, critical to the development of valid spike sorting algorithms.
A Potent and Broad Neutralizing Antibody Recognizes and Penetrates the HIV Glycan Shield
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pejchal, Robert; Doores, Katie J.; Walker, Laura M.
The HIV envelope (Env) protein gp120 is protected from antibody recognition by a dense glycan shield. However, several of the recently identified PGT broadly neutralizing antibodies appear to interact directly with the HIV glycan coat. Crystal structures of antigen-binding fragments (Fabs) PGT 127 and 128 with Man{sub 9} at 1.65 and 1.29 angstrom resolution, respectively, and glycan binding data delineate a specific high mannose-binding site. Fab PGT 128 complexed with a fully glycosylated gp120 outer domain at 3.25 angstroms reveals that the antibody penetrates the glycan shield and recognizes two conserved glycans as well as a short {beta}-strand segment ofmore » the gp120 V3 loop, accounting for its high binding affinity and broad specificify. Furthermore, our data suggest that the high neutralization potency of PGT 127 and 128 immunoglobulin Gs may be mediated by cross-linking Env trimers on the viral surface.« less
NASA Astrophysics Data System (ADS)
Julia, Jordi; Al-Amri, Abdullah; Pasyanos, Michael; Rodgers, Arthur; Matzel, Eric; Nyblade, Andrew
2013-04-01
Seismic imaging of the lithosphere under the Arabian shield and platform is critical to help answer important geologic questions of regional and global interest. The Arabian Shield can be regarded as an amalgamation of several arcs and microplates of Proterozoic age that culminated in the accretion of the Arabian portion of Gondwana during the Pan-African event at ~550 Ma and the role of important geologic features observed on the surface - such as the lineaments and shear zones separating the Proterozoic terrains in the shield - is not completely understood. Also, current models of Precambrian crustal evolution predict that Proterozoic terranes are underlain by fertile (FeO-rich) cratonic roots that should promote the production of mafic magmas and underplating of the Arabian shield terranes, and the shield contains Tertiary and Quaternary volcanic rocks related to the early stages of the Red Sea formation that might also be related to plume-related lithospheric "erosion". In order to better understand these relationships, we are developing new velocity models of litospheric structure for the Arabian shield and platform from the joint inversion of up to four seismic data sets: P-wave receiver functions, S-wave receiver functions, dispersion velocities from surface-waves, and dispersion velocities from ambient-noise cross-correlations. The joint inversion combines constraints on crustal thickness from P-wave receiver functions, constraints on lithospheric thickness from S-wave receiver functions and constraints on S-velocity and S-velocity gradients from dispersion velocities to produce detailed S-velocity profiles under single recording stations. We will present S-velocity profiles for a number of permanent stations operated by the Saudi Geological Survey and the King ing Abdulaziz Center for Science and Technology as well as stations from past temporary deployments and discuss the implications of the velocity models regarding composition and tectonics of the Arabian shield and platform.
Physical basis of radiation protection in space travel
NASA Astrophysics Data System (ADS)
Durante, Marco; Cucinotta, Francis A.
2011-10-01
The health risks of space radiation are arguably the most serious challenge to space exploration, possibly preventing these missions due to safety concerns or increasing their costs to amounts beyond what would be acceptable. Radiation in space is substantially different from Earth: high-energy (E) and charge (Z) particles (HZE) provide the main contribution to the equivalent dose in deep space, whereas γ rays and low-energy α particles are major contributors on Earth. This difference causes a high uncertainty on the estimated radiation health risk (including cancer and noncancer effects), and makes protection extremely difficult. In fact, shielding is very difficult in space: the very high energy of the cosmic rays and the severe mass constraints in spaceflight represent a serious hindrance to effective shielding. Here the physical basis of space radiation protection is described, including the most recent achievements in space radiation transport codes and shielding approaches. Although deterministic and Monte Carlo transport codes can now describe well the interaction of cosmic rays with matter, more accurate double-differential nuclear cross sections are needed to improve the codes. Energy deposition in biological molecules and related effects should also be developed to achieve accurate risk models for long-term exploratory missions. Passive shielding can be effective for solar particle events; however, it is limited for galactic cosmic rays (GCR). Active shielding would have to overcome challenging technical hurdles to protect against GCR. Thus, improved risk assessment and genetic and biomedical approaches are a more likely solution to GCR radiation protection issues.
Context-Sensitive Adjustment of Cognitive Control in Dual-Task Performance
ERIC Educational Resources Information Center
Fischer, Rico; Gottschalk, Caroline; Dreisbach, Gesine
2014-01-01
Performing 2 highly similar tasks at the same time requires an adaptive regulation of cognitive control to shield prioritized primary task processing from between-task (cross-talk) interference caused by secondary task processing. In the present study, the authors investigated how implicitly and explicitly delivered information promotes the…
Implementation of radiation shielding calculation methods. Volume 2: Seminar/Workshop notes
NASA Technical Reports Server (NTRS)
Capo, M. A.; Disney, R. K.
1971-01-01
Detailed descriptions are presented of the input data for each of the MSFC computer codes applied to the analysis of a realistic nuclear propelled vehicle. The analytical techniques employed include cross section data, preparation, one and two dimensional discrete ordinates transport, point kernel, and single scatter methods.
Internet Attack Traceback: Cross-Validation and Pebble-Trace
2013-02-28
stolen-cyber-attack. [3] Hacked: Data breach costly for Ohio State, victims of compromised info http://www.thelantern.com/campus/hacked- data ... breach -costly-for-ohio-state-victims-of-compromised-info-1.1831311. [4] S. C. Lee and C. Shields, “Tracing the Source of Network Attack: A Technical
NEUTRON PHYSICS DIVISION ANNUAL PROGRESS REPORT. Period Ending September 1, 1962
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1963-01-11
A total of 74 subsections are included in the report. The information in 4 subsections was previously abstracted in NSA. Separate abstracts were prepared for 38 of the subsections. Those sections for which no abstracts were prepared contain information on prompt neutron lifetime, Rover critical experiments, Pu/sup 239/ fission, neutron decay, the O5R code, alpha scattering, 8 and P wavelengths, proton scattering, deuteron scattering, local optical potentials, N. S. Savamah radiation leakage, reactor shielding, cross section data analysis, gamma transport, gamma energy deposition, gaussian integration, data interpolation, neutron scattering, neutron energy deposition, space vehicles, computer analyses, shielding, positron sources, andmore » secondary particles. (J.R.D.)« less
Gas Contamination In Plasma-Arc-Welded Aluminum
NASA Technical Reports Server (NTRS)
Mcclure, John C.; Torres, Martin R.; Gurevitch, Alan C.; Newman, Robert A.
1992-01-01
Document describes experimental investigation on visible and tactile effects of gaseous contaminants in variable-polarity plasma arc (VPPA) welding of 2219 T-87 aluminum alloy. Contaminant gases (nitrogen, methane, oxygen, and hydrogen) introduced in argon arc and in helium shield gas in various controlled concentrations. Report represents results of experiments in form of photographs of fronts, backs, polished cross sections, and etched cross sections of welds made with various contaminants at various concentrations. Provides detailed discussion of conditions under which welds made.
Investigating the use of Egyptian blue in Roman Egyptian portraits and panels from Tebtunis, Egypt
NASA Astrophysics Data System (ADS)
Ganio, Monica; Salvant, Johanna; Williams, Jane; Lee, Lynn; Cossairt, Oliver; Walton, Marc
2015-11-01
The use of the pigment Egyptian blue is investigated on a corpus of fifteen mummy portraits and Roman-period paintings from Tebtunis, Egypt, housed in the Phoebe A. Hearst Museum of Anthropology at the University of California, Berkeley. Egyptian blue has a strong luminescence response in the near infrared that can be exploited to created wide-field images noninvasively showing the distribution of the pigment on a work of art. A growing body of publications in the last decade highlights the increasing use of this tool and its sensitive detection limits. However, the technique is not wavelength specific. Both excitation and emission occur in a broad range. Although Egyptian blue has a strong emission in the NIR, a myriad of other compounds may emit light in this spectral region when excited in the visible. The limited number of studies including complementary analysis to verify the presence of Egyptian blue does not allow its identification on the basis of NIR luminescence alone. Through the use of in situ X-ray fluorescence and X-ray diffraction, and scanning electron microscopy/energy-dispersive spectroscopy of cross sections, this paper confirms the identification of Egyptian blue by NIR luminescence in unexpected areas, i.e., those not blue in appearance.
Green, K Kappmeier; Venter, G J
2007-12-01
The attractiveness of various colours, colour combinations and sizes of sticky traps of the 3-dimensional trap (3DT), cross-shaped target (XT), rectangular screen (RT) and monopanels were evaluated for their efficacy to capture Glossina austeni Newstead and G. brevipalpis Newstead in north-eastern KwaZulu-Natal, South Africa. The 3-dimensional shapes of the XT and 3DT in light blue (l.blue) and white were significantly (ca. 3.1-6.9 times) better than the RT for G. austeni. On bicoloured XTs, G. austeni landed preferentially on electric blue (e.blue) (58%) and black (63%) surfaces when used with white; while for G. brevipalpis, significantly more landed on e.blue (60-66%) surfaces when used with l.blue, black or white surfaces. Increased trap size increased the catches of G. brevipalpis females and both sexes of G. austeni significantly. Temoocid and polybutene sticky materials were equally effective and remained durable for 2-3 weeks. The glossy shine of trap surfaces did not have any significant effect on the attraction and landing responses of the two species. The overall trap efficiency of the e.blue/l.blue XT was 23% for G. brevipalpis and 28% for G. austeni, and that of the e.blue/black XT was 16% for G. brevipalpis and 51% for G. austeni. Larger monopanels, painted e.blue/black on both sides, increased the catches of G. austeni females significantly by up to four times compared to the standard e.blue/black XT. This monopanel would be recommended for use as a simple and cost effective survey tool for both species in South Africa.
NASA Technical Reports Server (NTRS)
Jeong, Myeong-Jae; Hsu, N. Christina; Kwiatkowska, Ewa J.; Franz, Bryan A.; Meister, Gerhard; Salustro, Clare E.
2012-01-01
The retrieval of aerosol properties from spaceborne sensors requires highly accurate and precise radiometric measurements, thus placing stringent requirements on sensor calibration and characterization. For the Terra/Moderate Resolution Imaging Spedroradiometer (MODIS), the characteristics of the detectors of certain bands, particularly band 8 [(B8); 412 nm], have changed significantly over time, leading to increased calibration uncertainty. In this paper, we explore a possibility of utilizing a cross-calibration method developed for characterizing the Terral MODIS detectors in the ocean bands by the National Aeronautics and Space Administration Ocean Biology Processing Group to improve aerosol retrieval over bright land surfaces. We found that the Terra/MODIS B8 reflectance corrected using the cross calibration method resulted in significant improvements for the retrieved aerosol optical thickness when compared with that from the Multi-angle Imaging Spectroradiometer, Aqua/MODIS, and the Aerosol Robotic Network. The method reported in this paper is implemented for the operational processing of the Terra/MODIS Deep Blue aerosol products.
Glaciation and regional ground-water flow in the Fennoscandian Shield: Site 94
Provost, Alden M.; Voss, Clifford I.; Neuzil, C.E.
1998-01-01
Results from a regional-scale ground-water flow model of the Fennoscandian shield suggest that ground-water flow is strongly affected by surface conditions associated with climatic change and glaciation. The model was used to run a series of numerical simulations of variable-density ground-water flow in a 1500-km-long and approximately 10-km-deep cross-section that passes through southern Sweden. Ground-water flow and shield brine transport in the cross-sectional model are controlled by an assumed time evolution of surface conditions over the next 140 ka. Simulations show that, under periglacial conditions, permafrost may locally or extensively impede the free recharge or discharge of ground water. Below cold-based glacial ice, no recharge or discharge of ground water occurs. Both of these conditions result in the settling of shield brine and consequent freshening of near-surface water in areas of natural discharge blocked by permafrost. The presence of warm-based ice with basal melting creates a potential for ground-water recharge rates much larger than under present, ice-free conditions. Recharging basal meltwater can reach depths of a few kilometers in a few thousand years. The vast majority of recharged water is accommodated through storage in the volume of bedrock below the local area of recharge; regional (lateral) redistribution of recharged water by subsurface flow is minor over the duration of a glacial advance (~10 ka). During glacial retreat, the weight of the ice overlying a given surface location decreases, and significant upward flow of ground water may occur below the ice sheet due to pressure release, despite the continued potential for recharge of basal meltwater. Excess meltwater must exit from below the glacier through subglacial cavities and channels. Subsurface penetration of meltwater during glacial advance and up-flow during glacial retreat are greatest if the loading efficiency of the shield rock is low. The maximum rate of ground-water discharge occurs at the receding ice margin, and some discharge occurs below incursive post-glacial seas. The simulation results suggest that vertical movement of deep shield brines induced by the next few glacial cycles should not increase the concentration of dissolved solids significantly above present-day levels. However, the concentration of dissolved solids should decrease significantly at depths of up to several kilometers during periods of glacial meltwater recharge. The meltwater may reside in the subsurface for periods exceeding 10 ka and may bring oxygenated conditions to an otherwise reducing chemical environment.
NASA Technical Reports Server (NTRS)
Hilmer, Robert V.; Voigt, Gerd-Hannes
1995-01-01
A tilt-dependent magnetic field model of the Earth's magnetosphere with variable magnetopause standoff distance is presented. Flexible analytic representations for the ring and cross-tail currents, each composed of the elements derived from the Tsyganenko and Usmanov (1982) model, are combined with the fully shielded vacuum dipole configurations of Voigt (1981). Although the current sheet does not warp in the y-z plane, changes in the shape and position of the neutral sheet with dipole tilt are consistent with both MHD equilibrium theory and observations. In addition, there is good agreement with observed Delta B profiles and the average equatorial contours of magnetic field magnitude. While the dipole field is rigorously shielded within the defined magnetopause, the ring and cross-tails currents are not similarly confined, consequently, the model's region of validity is limited to the inner magnetosphere. The model depends on four independent external parameters. We present a simple but limited method of simulating several substorm related magnetic field changes associated with the disrupion of the near-Earth cross-tail current sheet and collapse of the midnight magnetotail field region. This feature further facilitates the generation of magnetic field configuration time sequences useful in plasma convection simulations of real magnetospheric events.
Kambali, I; Suryanto, H; Parwanto
2016-06-01
Routine production of F-18 radionuclide using proton beams accelerated in a cyclotron could potentially generate residual radioisotopes in the cyclotron vicinity which eventually become major safety concerns over radiation exposure to the workers. In this investigation, a typical 11-MeV proton, self-shielded cyclotron has been assessed for its residual radiation sources in the cyclotron's shielding, tank/chamber, cave wall as well as target system. Using a portable gamma ray spectroscopy system, the radiation measurement in the cyclotron environment has been carried out. Experimental results indicate that relatively long-lived radioisotopes such as Mn-54, Zn-65 and Eu-152 are detected in the inner and outer surface of the cyclotron shielding respectively while Mn-54 spectrum is observed around the cyclotron chamber. Weak intensity of Eu-152 radioisotope is again spotted in the inner and outer surface of the cyclotron cave wall. Angular distribution measurement of the Eu-152 shows that the intensity slightly drops with increasing observation angle relative to the proton beam incoming angle. In the target system, gamma rays from Co-56, Mn-52, Co-60, Mn-54, Ag-110 m are identified. TALYS-calculated nuclear cross-section data are used to study the origins of the radioactive by-products.
Fragmentation studies of relativistic iron ions using plastic nuclear track detectors.
Scampoli, P; Durante, M; Grossi, G; Manti, L; Pugliese, M; Gialanella, G
2005-01-01
We measured fluence and fragmentation of high-energy (1 or 5 A GeV) 56Fe ions accelerated at the Alternating Gradient Synchrotron or at the NASA Space Radiation Laboratory (Brookhaven National Laboratory, NY, USA) using solid-state CR-39 nuclear track detectors. Different targets (polyethylene, PMMA, C, Al, Pb) were used to produce a large spectrum of charged fragments. CR-39 plastics were exposed both in front and behind the shielding block (thickness ranging from 5 to 30 g/cm2) at a normal incidence and low fluence. The radiation dose deposited by surviving Fe ions and charged fragments was measured behind the shield using an ionization chamber. The distribution of the measured track size was exploited to distinguish the primary 56Fe ions tracks from the lighter fragments. Measurements of projectile's fluence in front of the shield were used to determine the dose per incident particle behind the block. Simultaneous measurements of primary 56Fe ion tracks in front and behind the shield were used to evaluate the fraction of surviving iron projectiles and the total charge-changing fragmentation cross-section. These physical measurements will be used to characterize the beam used in parallel biological experiments. c2005 COSPAR. Published by Elsevier Ltd. All rights reserved.
Background studies in gas ionizing x ray detectors
NASA Technical Reports Server (NTRS)
Eldridge, Hudson B.
1989-01-01
The background response of a gas ionizing proportional x ray detector is estimated by solving the one dimensional photon transport equation for two regions using Monte Carlo techniques. The solution was effected using the SSL VAX 780 and the CRAY XMP computers at Marshall Space Flight Center. The isotropic photon energy spectrum encompassing the range from 1 to 1000 KeV incident onto the first region, the shield, is taken so as to represent the measured spectrum at an altitude of 3 mb over Palastine, Texas. The differential energy spectrum deposited in the gas region, xenon, over the range of 0 to 100 KeV is written to an output file. In addition, the photon flux emerging from the shield region, tin, over the range of 1 to 1000 KeV is also tabulated and written to a separate file. Published tabular cross sections for photoelectric, elastic and inelastic Compton scattering as well as the total absorption coefficient are used. Histories of each incident photon as well as secondary photons from Compton and photoelectric interactions are followed until the photon either is absorbed or exits from the regions under consideration. The effect of shielding thickness upon the energy spectrum deposited in the xenon region for this background spectrum incident upon the tin shield was studied.
Sander, Birgit; Markvart, Jakob; Kessel, Line; Argyraki, Aikaterini; Johnsen, Kjeld
2015-01-01
The study investigated the effect of bright blue-enriched versus blue-suppressed indoor light on sleep and wellbeing of healthy participants over 65 years. Twenty-nine participants in 20 private houses in a uniform settlement in Copenhagen were exposed to two light epochs of 3 weeks with blue-enriched (280 lux) and 3 weeks blue-suppressed (240 lux) indoor light or vice versa from 8 to 13 pm in a randomized cross-over design. The first light epoch was in October, the second in November and the two light epochs were separated by one week. Participants were examined at baseline and at the end of each light epoch. The experimental indoor light was well tolerated by the majority of the participants. Sleep duration was 7.44 (95% CI 7.14–7.74) hours during blue-enriched conditions and 7.31 (95% CI 7.01–7.62) hours during blue-suppressed conditions (p = 0.289). Neither rest hours, chromatic pupillometry, nor saliva melatonin profile showed significant changes between blue-enriched and blue-suppressed epochs. Baseline Pittsburgh Sleep Quality Index (PSQI) was significantly worse in females; 7.62 (95% CI 5.13–10.0) versus 4.06 (95% CI 2.64–5.49) in males, p = 0.009. For females, PSQI improved significantly during blue-enriched light exposure (p = 0.007); no significant changes were found for males. The subjective grading of indoor light quality doubled from participants habitual indoor light to the bright experimental light, while it was stable between light epochs, although there were clear differences between blue-enriched and blue-suppressed electrical light conditions imposed. Even though the study was carried out in the late autumn at northern latitude, the only significant difference in Actiwatch-measured total blue light exposure was from 8 to 9 am, because contributions from blue-enriched, bright indoor light were superseded by contributions from daylight. PMID:26181467
An economic analysis of health plan conversions: are they in the public interest?
Beaulieu, Nancy Dean
2004-01-01
Over the last decade, managed-care companies have been consolidating on both a regional and national scale. More recently, nonprofit health plans have been converting to for-profit status, and this conversion has frequently occurred as a step to facilitate merger or acquisition with a for-profit company. Some industry observers attribute these managed-care marketplace trends to an industry shakeout resulting from increased competition in the sector. At the same time, these perceived competitive pressures have led to questions about the long-run viability of nonprofit health plans. Furthermore, some industry and government leaders believe that some nonprofits are already conducting themselves like for-profit health plans and question the state premium tax exemption ordinarily accorded to such plans. This paper examines related health policy issues through the lens of a case study of the proposed conversion of the CareFirst Blue Cross Blue Shield company to a for-profit public-stock company and its merger with the Wellpoint Corporation. Company executives and board members argued that CareFirst lacked access to sufficient capital and faced serious threats to its viability as a financially healthy nonprofit health care company. They also argued that CareFirst and its beneficiaries would benefit from merger through enhanced economies of scale and product-line extensions. Critics of the proposed conversion and merger raised concerns about the adverse impacts on access to care, coverage availability, quality of care, safety-net providers, and the cost of health insurance. Analyses demonstrate that CareFirst wields substantial market power in its local market, that it is unlikely to realize cost savings through expanded economies of scale, and that access to capital concerns are largely driven by the perceived need for further expansion through merger and acquisition. Although it is impossible to predict future changes in quality of care for CareFirst, analyses suggest that quality appears to be somewhat lower in for-profit national managed-care companies. Additional research is needed to assess the viability of true nonprofits, the potential effects of nonprofits and for-profit national managed-care plans on the evolution of local insurance and provider markets, and methods for effective oversight of nonprofit health plans.
Health Care Spending and Quality in Year 1 of the Alternative Quality Contract
Song, Zirui; Safran, Dana Gelb; Landon, Bruce E.; He, Yulei; Ellis, Randall P.; Mechanic, Robert E.; Day, Matthew P.; Chernew, Michael E.
2012-01-01
Background In 2009, Blue Cross Blue Shield of Massachusetts (BCBS) implemented a global payment system called the Alternative Quality Contract (AQC). Provider groups in the AQC system assume accountability for spending, similar to accountable care organizations that bear financial risk. Moreover, groups are eligible to receive bonuses for quality. Methods Seven provider organizations began 5-year contracts as part of the AQC system in 2009. We analyzed 2006–2009 claims for 380,142 enrollees whose primary care physicians (PCPs) were in the AQC system (intervention group) and for 1,351,446 enrollees whose PCPs were not in the system (control group). We used a propensity-weighted difference-in-differences approach, adjusting for age, sex, health status, and secular trends to isolate the treatment effect of the AQC in comparisons of spending and quality between the intervention group and the control group. Results Average spending increased for enrollees in both the intervention and control groups in 2009, but the increase was smaller for enrollees in the intervention group — $15.51 (1.9%) less per quarter (P = 0.007). Savings derived largely from shifts in outpatient care toward facilities with lower fees; from lower expenditures for procedures, imaging, and testing; and from a reduction in spending for enrollees with the highest expected spending. The AQC system was associated with an improvement in performance on measures of the quality of the management of chronic conditions in adults (P<0.001) and of pediatric care (P = 0.001), but not of adult preventive care. All AQC groups met 2009 budget targets and earned surpluses. Total BCBS payments to AQC groups, including bonuses for quality, are likely to have exceeded the estimated savings in year 1. Conclusions The AQC system was associated with a modest slowing of spending growth and improved quality of care in 2009. Savings were achieved through changes in referral patterns rather than through changes in utilization. The long-term effect of the AQC system on spending growth depends on future budget targets and providers’ ability to further improve efficiencies in practice. (Funded by the Commonwealth Fund and others.) PMID:21751900
WE-G-BRA-02: SafetyNet: Automating Radiotherapy QA with An Event Driven Framework
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hadley, S; Kessler, M; Litzenberg, D
2015-06-15
Purpose: Quality assurance is an essential task in radiotherapy that often requires many manual tasks. We investigate the use of an event driven framework in conjunction with software agents to automate QA and eliminate wait times. Methods: An in house developed subscription-publication service, EventNet, was added to the Aria OIS to be a message broker for critical events occurring in the OIS and software agents. Software agents operate without user intervention and perform critical QA steps. The results of the QA are documented and the resulting event is generated and passed back to EventNet. Users can subscribe to those eventsmore » and receive messages based on custom filters designed to send passing or failing results to physicists or dosimetrists. Agents were developed to expedite the following QA tasks: Plan Revision, Plan 2nd Check, SRS Winston-Lutz isocenter, Treatment History Audit, Treatment Machine Configuration. Results: Plan approval in the Aria OIS was used as the event trigger for plan revision QA and Plan 2nd check agents. The agents pulled the plan data, executed the prescribed QA, stored the results and updated EventNet for publication. The Winston Lutz agent reduced QA time from 20 minutes to 4 minutes and provided a more accurate quantitative estimate of radiation isocenter. The Treatment Machine Configuration agent automatically reports any changes to the Treatment machine or HDR unit configuration. The agents are reliable, act immediately, and execute each task identically every time. Conclusion: An event driven framework has inverted the data chase in our radiotherapy QA process. Rather than have dosimetrists and physicists push data to QA software and pull results back into the OIS, the software agents perform these steps immediately upon receiving the sentinel events from EventNet. Mr Keranen is an employee of Varian Medical Systems. Dr. Moran’s institution receives research support for her effort for a linear accelerator QA project from Varian Medical Systems. Other quality projects involving her effort are funded by Blue Cross Blue Shield of Michigan, Breast Cancer Research Foundation, and the NIH.« less
Health care spending and quality in year 1 of the alternative quality contract.
Song, Zirui; Safran, Dana Gelb; Landon, Bruce E; He, Yulei; Ellis, Randall P; Mechanic, Robert E; Day, Matthew P; Chernew, Michael E
2011-09-08
In 2009, Blue Cross Blue Shield of Massachusetts (BCBS) implemented a global payment system called the Alternative Quality Contract (AQC). Provider groups in the AQC system assume accountability for spending, similar to accountable care organizations that bear financial risk. Moreover, groups are eligible to receive bonuses for quality. Seven provider organizations began 5-year contracts as part of the AQC system in 2009. We analyzed 2006-2009 claims for 380,142 enrollees whose primary care physicians (PCPs) were in the AQC system (intervention group) and for 1,351,446 enrollees whose PCPs were not in the system (control group). We used a propensity-weighted difference-in-differences approach, adjusting for age, sex, health status, and secular trends to isolate the treatment effect of the AQC in comparisons of spending and quality between the intervention group and the control group. Average spending increased for enrollees in both the intervention and control groups in 2009, but the increase was smaller for enrollees in the intervention group--$15.51 (1.9%) less per quarter (P=0.007). Savings derived largely from shifts in outpatient care toward facilities with lower fees; from lower expenditures for procedures, imaging, and testing; and from a reduction in spending for enrollees with the highest expected spending. The AQC system was associated with an improvement in performance on measures of the quality of the management of chronic conditions in adults (P<0.001) and of pediatric care (P=0.001), but not of adult preventive care. All AQC groups met 2009 budget targets and earned surpluses. Total BCBS payments to AQC groups, including bonuses for quality, are likely to have exceeded the estimated savings in year 1. The AQC system was associated with a modest slowing of spending growth and improved quality of care in 2009. Savings were achieved through changes in referral patterns rather than through changes in utilization. The long-term effect of the AQC system on spending growth depends on future budget targets and providers' ability to further improve efficiencies in practice. (Funded by the Commonwealth Fund and others.).
Metamorphosis of dentistry. Update on alternative delivery systems.
Tekavec, M M
1988-01-01
In 1985, Americans spent $27.8 billion for dental care. Patients paid $18 billion out-of-pocket, while private health insurance paid about $9.2 billion. Public programs paid approximately $600 million primarily through Medicaid. Commercial insurance carriers have increased their market share to more than 80 million subscribers, or more than 70 per cent of the total market. Dental service corporations and Blue Cross/Blue Shield plans cover more than 30 million subscribers, while independent plans have policies with more than 6 million customers. Dentistry today is a big business, and Big Business wants to make it their business. What makes health care vastly different from the manufacture and sale of microwaves, furniture and clothing, or the production and serving of fast foods is that the provider is in a unique relationship with the consumer/patient and will always have a large measure of control for this reason. Receiving dental care is not the same as purchasing a new pair of tennis shoes, but good business practices from other business arenas can make it possible for greater numbers of people to have greater access to it. Over the past 25 years a metamorphosis of dentistry has been generated by a rather constant interplay between the various involved parties to obtain a position of least financial risk. Insurance carriers and/or administrative intermediaries want the risk placed on the dentist, employers want the administrators to take it, and dentists want employers, administrators, or patients to assume it. The future will see the gradual evolvement of equitable plans dividing the risk among the four principle parties. Plans are being put in place today that already reflect this. A viable alternative delivery system means: Dental care providers who have the knowledge and incentive to perform quality care; administrators willing to share some of the risk; and employers and consumers who are sophisticated and realistic in their demands in today's marketplace. All these factions are currently interacting to create the new dental picture we see today--and will see in the future.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shaughnessy, D A; Gostic, J M; Moody, K J
2011-11-21
The ability to collect solid debris from the target chamber following a NIF shot has application for both capsule diagnostics, particularly for fuel-ablator mix, and measuring cross sections relevant to the Stockpile Stewardship program and nuclear astrophysics. Simulations have shown that doping the capsule with up to 10{sup 15} atoms of an impurity not otherwise found in the capsule does not affect its performance. The dopant is an element that will undergo nuclear activations during the NIF implosion, forming radioactive species that can be collected and measured after extraction from the target chamber. For diagnostics, deuteron or alpha induced reactionsmore » can be used to probe the fuel-ablator mix. For measuring neutron cross sections, the dopant should be something that is sensitive to the 14 MeV neutrons produced through the fusion of deuterium and tritium. Developing the collector is a challenge due to the extreme environment of the NIF chamber. The collector surface is exposed to a large photon flux from x-rays and unconverted laser light before it is exposed to a debris wind that is formed from vaporized material from the target chamber center. The photons will ablate the collector surface to some extent, possibly impeding the debris from reaching the collector and sticking. In addition, the collector itself must be mechanically strong enough to withstand the large amount of energy it will be exposed to, and it should be something that will be easy to count and chemically process. In order to select the best material for the collector, a variety of different metals have been tested in the NIF chamber. They were exposed to high-energy laser shots in order to evaluate their postshot surface characterization, morphology, degree of melt, and their ability to retain debris from the chamber center. The first set of samples consisted of 1 mm thick pieces of aluminum that had been fielded in the chamber as blast shields protecting the neutron activation diagnostic. Ten of these pieces were fielded at the equator and one was fielded on the pole. The shields were analyzed using a combination of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), x-ray fluorescence (XRF), neutron activation analysis (NAA) and chemical leaching followed by mass spectrometry. On each shield, gold debris originating from the gold hohlraum was observed, as well as large quantities of debris that were present in the center of the target chamber at the time of the shot (i.e., stainless steel, indium, copper, etc.) Debris was visible in the SEM as large blobs or splats of material that had encountered the surface of the aluminum and stuck. The aluminum itself had obviously melted and condensed, and some of the large debris splats arrived after the surface had already hardened. Melt depth was determined by cross sectioning the pieces and measuring the melted surface layers via SEM. After the SEM analysis was completed, the pieces were sent for NAA at the USGS reactor and were analyzed by U. Greife at the Colorado School of Mines. The NAA showed that the majority of gold mass present on the shields was not in the form of large blobs and splats, but was present as small particulates that had most likely formed as condensed vapor. Further analysis showed that the gold was entrained in the melted aluminum surface layers and did not extend down into the bulk of the aluminum. Once the gold mass was accounted for from the NAA, it was determined that the aluminum fielded at the equator was collecting a fraction of the total gold hohlraum mass equivalent to 120% {+-} 10% of the solid angle subtended by the shield. The attached presentation has more information on the results of the aluminum blast shield analysis. In addition to the information given in the presentation, the surfaces of the shields have been chemically leached and submitted for mass spectrometric analysis. The results from that analysis are expected to arrive after the due date of this report and will be written up at a later time. Based on the results of the aluminum blast shield analysis, it was determined that additional materials needed to be tested as potential collectors in the NIF chamber. 1-2 mm thick pieces of tantalum, niobium, vanadium, silver, titanium, molybdenum, and graphite foil were fielded in the Wedge Range Filter (WRF) mount at a distance of 50 cm from target chamber center during the shock timing campaign. The pieces were subsequently removed and analyzed in a similar fashion to the aluminum shields. As of this writing, the pieces are still under analysis, but initial results indicate that gold debris was collected on the various materials. Currently, the pieces are being cross-sectioned so that the melt depths of each material can be compared. In addition, NAA and/or mass spectrometry will be performed in order to determine the total gold mass that was collected on each surface.« less
Measurement of Charged Particle Interactions in Spacecraft and Planetary Habitat Shielding Materials
NASA Technical Reports Server (NTRS)
Zeitlin, Cary J.; Heilbronn, Lawrence H.; Miller, Jack; Wilson, John W.; Singleterry, Robert C., Jr.
2003-01-01
Accurate models of health risks to astronauts on long-duration missions outside the geomagnetosphere will require a full understanding of the radiation environment inside a spacecraft or planetary habitat. This in turn requires detailed knowledge of the flux of incident particles and their propagation through matter, including the nuclear interactions of heavy ions that are a part of the Galactic Cosmic Radiation (GCR). The most important ions are likely to be iron, silicon, oxygen, and carbon. Transport of heavy ions through complex shielding materials including self-shielding of tissue modifies the radiation field at points of interest (e.g., at the blood-forming organs). The incident flux is changed by two types of interactions: (1) ionization energy loss, which results in reduced particle velocity and higher LET (Linear Energy Transfer); and (2) nuclear interactions that fragment the incident nuclei into less massive ions. Ionization energy loss is well understood, nuclear interactions less so. Thus studies of nuclear fragmentation at GCR-like energies are needed to fill the large gaps that currently exist in the database. These can be done at only a few accelerator facilities where appropriate beams are available. Here we report results from experiments performed at the Brookhaven National Laboratory s Alternating Gradient Synchrotron (AGS) and the Heavy Ion Medical Accelerator in Chiba, Japan (HIMAC). Recent efforts have focused on extracting charge-changing and fragment production cross sections from silicon beams at 400, 600, and 1200 MeV/nucleon. Some energy dependence is observed in the fragment production cross sections, and as in other data sets the production of fragments with even charge numbers is enhanced relative to those with odd charge numbers. These data are compared to the NASA-LaRC model NUCFRG2. The charge-changing cross section data are compared to recent calculations using an improved model due to Tripathi, which accurately predicts the observed (slight) energy dependence. An additional set of data will be presented from an analysis of shielding material performance in the 1 GeV/nucleon iron beam at the AGS. A wide variety of candidate materials for spacecraft construction, as well as elemental targets, have been placed in this beam and their effects on transmitted dose and dose equivalent measured. The results support a prediction by J. Wilson et al. that hydrogen-loaded materials give the greatest dose reduction per unit mass.
Hanni, Matti; Lantto, Perttu; Ilias, Miroslav; Jensen, Hans Jorgen Aagaard; Vaara, Juha
2007-10-28
Relativistic effects on the (129)Xe nuclear magnetic resonance shielding and (131)Xe nuclear quadrupole coupling (NQC) tensors are examined in the weakly bound Xe(2) system at different levels of theory including the relativistic four-component Dirac-Hartree-Fock (DHF) method. The intermolecular interaction-induced binary chemical shift delta, the anisotropy of the shielding tensor Deltasigma, and the NQC constant along the internuclear axis chi( parallel) are calculated as a function of the internuclear distance. DHF shielding calculations are carried out using gauge-including atomic orbitals. For comparison, the full leading-order one-electron Breit-Pauli perturbation theory (BPPT) is applied using a common gauge origin. Electron correlation effects are studied at the nonrelativistic (NR) coupled-cluster singles and doubles with perturbational triples [CCSD(T)] level of theory. The fully relativistic second-order Moller-Plesset many-body perturbation (DMP2) theory is used to examine the cross coupling between correlation and relativity on NQC. The same is investigated for delta and Deltasigma by BPPT with a density functional theory model. A semiquantitative agreement between the BPPT and DHF binary property curves is obtained for delta and Deltasigma in Xe(2). For these properties, the currently most complete theoretical description is obtained by a piecewise approximation where the uncorrelated relativistic DHF results obtained close to the basis-set limit are corrected, on the one hand, for NR correlation effects and, on the other hand, for the BPPT-based cross coupling of relativity and correlation. For chi( parallel), the fully relativistic DMP2 results obtain a correction for NR correlation effects beyond MP2. The computed temperature dependence of the second virial coefficient of the (129)Xe nuclear shielding is compared to experiment in Xe gas. Our best results, obtained with the piecewise approximation for the binary chemical shift combined with the previously published state of the art theoretical potential energy curve for Xe(2), are in excellent agreement with the experiment for the first time.
Böhmdorfer, Stefan; Oberlerchner, Josua Timotheus; Fuchs, Christina; Rosenau, Thomas; Grausgruber, Heinrich
2018-01-01
Anthocyanins are abundant secondary metabolites responsible for most blue to blue-black, and red to purple colors of various plant organs. In wheat grains, anthocyanins are accumulated in the pericarp and/or aleurone layer. Anthocyanin pigmented wheat grains can be processed into functional foods with potential health benefits due to the antioxidant properties of the anthocyanins. The grain anthocyanin content can be increased by pyramidizing the different genes responsible for the accumulation of anthocyanins in the different grain layers. Our objective was to develop a high-performance thin-layer chromatography (HPTLC) method that allows the determination of both the anthocyanin profile and the total pigment concentration. Thereby, selection of breeding lines with significantly higher grain anthocyanin content from purple pericarp × blue aleurone wheat crosses should become more efficient than selection based on only visual scoring of grain color and the unspecific determination of anthocyanin concentration by UV/Vis spectroscopy. A wide variability in the grain anthocyanin content was observed in breeding lines and check varieties. The highest concentration of anthocyanins was observed in deep purple (i.e. combination of the purple pericarp and blue aleurone genetics) grained breeding lines, followed by blue aleurone and purple pericarp genotypes. Determination of the total anthocyanin content was included into the chromatographic analysis, rendering an additional photometric analysis unnecessary. Ten target zones were identified in anthocyanin pigmented wheat grains; four of these zones were typically for blue aleurone types, five for purple pericarp types, and one (i.e. kuromanin glucoside) was characteristic for both. Chemometrics applied to the anthocyanin profile recorded by scanning densitometry revealed that peak heights and peak areas are highly correlated and that seven out of the ten target zones were responsible for about 90% of the total variation in the germplasm. Multivariate analysis of these seven target zones allowed not only a separation of the genetic material into purple, blue and deep purple grained genotypes, but also the identification of genotypes with a specific anthocyanin pattern. Thereby, the original classification by visual scoring was overruled in about one-third of the breeding lines. The presented HPTLC method with à côté calibration allowed the profiling of the pigments and quantification of wheat grain anthocyanin content in a single analysis, replacing UV/Vis spectroscopy with subsequent HPLC analysis. Moreover, no sample preparation apart from extraction and filtration is required, and more than 15 samples can be evaluated in one analysis run, corresponding to several dozens of samples per day. Hence, the method fulfills the requirements for screening methods in early generations of a plant breeding program such as high-throughput, small sample size, high repeatability, fast determination, and reasonable costs per sample. Combined with multivariate statistical analysis, the anthocyanin pattern allowed the validation of the genetic background in the offspring of purple × blue wheat crosses and, therefore, the efficient selection of genotypes exhibiting both the cyanidin and delphinidin aglycon.
Total Electron-Impact Ionization Cross-Sections of CFx and NFx (x = 1 - 3)
NASA Technical Reports Server (NTRS)
Huo, Winifred M.; Tarnovsky, Vladimir; Becker, Kurt H.; Kwak, Dochan (Technical Monitor)
2001-01-01
The discrepancy between experimental and theoretical total electron-impact ionization cross sections for a group of fluorides, CFx, and NFx, (x = 1 - 3), is attributed to the inadequacies in previous theoretical models. Cross-sections calculated using a recently developed siBED (simulation Binary-Encounter-Dipole) model that takes into account the shielding of the long-range dipole potential between the scattering electron and target are in agreement with experimentation. The present study also carefully reanalyzed the previously reported experimental data to account for the possibility of incomplete collection of fragment ions and the presence of ion-pair formation channels. For NF3, our experimental and theoretical cross-sections compare well with the total ionization cross-sections recently reported by Haaland et al. in the region below dication formation.
Quantum tunneling resonant electron transfer process in Lorentzian plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hong, Woo-Pyo; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 426-791
The quantum tunneling resonant electron transfer process between a positive ion and a neutral atom collision is investigated in nonthermal generalized Lorentzian plasmas. The result shows that the nonthermal effect enhances the resonant electron transfer cross section in Lorentzian plasmas. It is found that the nonthermal effect on the classical resonant electron transfer cross section is more significant than that on the quantum tunneling resonant charge transfer cross section. It is shown that the nonthermal effect on the resonant electron transfer cross section decreases with an increase of the Debye length. In addition, the nonthermal effect on the quantum tunnelingmore » resonant electron transfer cross section decreases with increasing collision energy. The variation of nonthermal and plasma shielding effects on the quantum tunneling resonant electron transfer process is also discussed.« less
Rauch, Philippe; Merlin, Jean-Louis; Leufflen, Lea; Salleron, Julia; Harlé, Alexandre; Olivier, Pierre; Marchal, Frédéric
2016-09-01
Although morbidity is reduced when sentinel lymph node (SLN) biopsy is performed with dual isotopic and blue dye identification, the effectiveness of adding blue dye to radioisotope remains debated because side effects including anaphylactic reactions. Using data from a prospectively maintained database, 1884 lymph node-negative breast cancer patients who underwent partial mastectomy with SLN mapping by a dual-tracer using patent blue dye (PBD) and radioisotope were retrospectively studied between January 2000 and July 2013. Patients with tumors <3 cm and with >1 node detected by one of the two techniques (N = 1024) were included in this real-life cross-sectional study. Among the 1024 patients, 274 had positive SLN detected by isotopic and/or PBD staining. Only 4 patients having no detectable radioactivity in the axilla had SLN identified only by PBD staining (blue-only) while 26 patients had SLN only identified by isotopic detection (hot-only) illustrating failure rates of 9.5% (26/274) and 1.5% (4/274), respectively. Among these four patients, two had negative lymphoscintigraphy. Therefore, the contribution of PBD to metastatic nodes identification was relevant for only 2/274 patients (0.8%). Three patients (0.3%) had an allergic reaction with PBD, and anaphylactic shock occurred in two cases (0.2%). The added-value of PBD to reduce the false-negative rate of SLN mapping is only limited to the rare cases in which no radioactivity is detectable in the axilla (<1%). When a radioisotope mapping agent is available, the use of PBD should be avoided, because it can induce anaphylaxis. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Nucleon and heavy-ion total and absorption cross section for selected nuclei
NASA Technical Reports Server (NTRS)
Wilson, J. W.; Costner, C. M.
1975-01-01
Approximate solutions of the coupled-channel equations for high-energy composite particle scattering are obtained and are applied to the nuclear scattering problem. Relationships between several approximation procedures are established and discussed. The eikonal formalism is used with a small-angle approximation to calculate the coherent elastic scattered amplitude from which total and absorption cross sections are derived. Detailed comparisons with nucleon-nucleus experiments show agreement within 5 percent except at lower energies where the eikonal approximation is of questionable accuracy. Even at these lower energies, agreement is within 15 percent. Tables of cross sections required for cosmic heavy-ion transport and shielding studies are presented.
NASA Astrophysics Data System (ADS)
Anderson, C. J.; Luciw, N. J.; Li, Y.-C.; Kuo, C. Y.; Yadav, J.; Masui, K. W.; Chang, T.-C.; Chen, X.; Oppermann, N.; Liao, Y.-W.; Pen, U.-L.; Price, D. C.; Staveley-Smith, L.; Switzer, E. R.; Timbie, P. T.; Wolz, L.
2018-05-01
We report results from 21-cm intensity maps acquired from the Parkes radio telescope and cross-correlated with galaxy maps from the 2dF galaxy survey. The data span the redshift range 0.057 < z < 0.098 and cover approximately 1300 deg2 over two long fields. Cross-correlation is detected at a significance of 5.7 σ. The amplitude of the cross-power spectrum is low relative to the expected dark matter power spectrum, assuming a neutral hydrogen (H I) bias and mass density equal to measurements from the ALFALFA survey. The decrement is pronounced and statistically significant at small scales. At k ˜ 1.5 h Mpc-1, the cross-power spectrum is more than a factor of 6 lower than expected, with a significance of 15.3 σ. This decrement indicates a lack of clustering of neutral hydrogen (H I), a small correlation coefficient between optical galaxies and H I, or some combination of the two. Separating 2dF into red and blue galaxies, we find that red galaxies are much more weakly correlated with H I on k ˜ 1.5 h Mpc-1 scales, suggesting that H I is more associated with blue star-forming galaxies and tends to avoid red galaxies.
Astronomical Data Center Bulletin, volume 1, number 3
NASA Technical Reports Server (NTRS)
Mead, J. M.; Warren, W. H., Jr.; Nagy, T. A.
1983-01-01
A catalog of galactic O-type stars, a machine-readable version of the bright star catalog, a two-micron sky survey, sky survey sources with problematical Durchmusterung identifications, data retrieval for visual binary stars, faint blue objects, the sixth catalog of galactic Wolf-Rayet stars, declination versus magnitude distribution, the SAO-HD-GC-DM cross index catalog, star cross-identification tables, astronomical sources, bibliographical star index search updates, DO-HD and HD-DO cross indices, and catalogs, are reviewed.
Accelerator-Based Studies of Heavy Ion Interactions Relevant to Space Biomedicine
NASA Technical Reports Server (NTRS)
Miller, J.; Heilbronn, L.; Zeitlin, C.
1999-01-01
Evaluation of the effects of space radiation on the crews of long duration space missions must take into account the interactions of high energy atomic nuclei in spacecraft and planetary habitat shielding and in the bodies of the astronauts. These heavy ions (i.e. heavier than hydrogen), while relatively small in number compared to the total galactic cosmic ray (GCR) charged particle flux, can produce disproportionately large effects by virtue of their high local energy deposition: a single traversal by a heavy charged particle can kill or, what may be worse, severely damage a cell. Research into the pertinent physics and biology of heavy ion interactions has consequently been assigned a high priority in a recent report by a task group of the National Research Council. Fragmentation of the incident heavy ions in shielding or in the human body will modify an initially well known radiation field and thereby complicate both spacecraft shielding design and the evaluation of potential radiation hazards. Since it is impractical to empirically test the radiation transport properties of each possible shielding material and configuration, a great deal of effort is going into the development of models of charged particle fragmentation and transport. Accurate nuclear fragmentation cross sections (probabilities), either in the form of measurements with thin targets or theoretical calculations, are needed for input to the transport models, and fluence measurements (numbers of fragments produced by interactions in thick targets) are needed both to validate the models and to test specific shielding materials and designs. Fluence data are also needed to characterize the incident radiation field in accelerator radiobiology experiments. For a number of years, nuclear fragmentation measurements at GCR-like energies have been carried out at heavy ion accelerators including the LBL Bevalac, Saturne (France), the Synchrophasotron and Nuklotron (Dubna, Russia), SIS-18 (GSI, Germany), the Alternating Gradient Synchrotron at Brookhaven National Laboratory (BNL AGS) and the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan. Until fairly recently most of these experiments were done to investigate fundamental problems in nuclear physics, but with the increasing interest in heavy charged particles on the part of the space flight, radiobiology and radiotherapy communities, an increasing number of experiments are being directed at these areas. Some of these measurements are discussed in references therein. Over the past several years, our group has taken cross section and fluence data at the AGS and HIMAC for several incident beams with nuclear charge, Z, between 6 and 26 at energies between 290 and 1050 MeV/nucleon. Iron (Z = 26) has been studied most extensively, since it is the heaviest ion present in significant numbers in the GCR. Targets have included tissue-equivalent and proposed shielding materials, as well as a variety of elemental targets for cross section measurements. Most of the data were taken along the beam axis, but measurements have been made off-axis, as well. Here we present selected data and briefly discuss some implications for spacecraft and planetary habitat design.
High chemical abundances in stripped Virgo spiral galaxies
NASA Technical Reports Server (NTRS)
Skillman, E. D.; Kennicutt, R. C.; Shields, G. A.
1993-01-01
Based on a comparison of the oxygen abundances in H 2 regions in field and Virgo cluster late type spiral galaxies, Shields, Skillman, & Kennicutt (1991) suggested that the highly stripped spiral galaxies in the Virgo cluster have systematically higher abundances than comparable field galaxies. In April 1991 and May 1992 we used the blue channel spectrograph on the MMT to obtain new observations of 30 H 2 regions in Virgo spiral galaxies. These spectra cover the wavelength range from (O II) lambda 3727 to (S II) lambda 6731. We now have observed at least 4 H II regions in 9 spiral galaxies in the Virgo cluster. Combining (O II) and (O III) line strengths, we calculate the H II region oxygen abundances based on the empirical calibration of Edmunds & Pagel (1984). These observations show: (1) The stripped, low luminosity Virgo spirals (N4689, N4571) truly have abundances characteristic of much more luminous field spirals; (2) Virgo spirals which show no evidence of stripping (N4651, N4713) have abundances comparable to field galaxies; and (3) Evidence for transition galaxies (e.g., N4254, N4321), with marginally stripped disks and marginal abundance enhancements. The new observations presented here confirm the validity of the oxygen over-abundances in the stripped Virgo spirals. Shields et al. (1991) discussed two different mechanisms for producing the higher abundances in the disks of stripped galaxies in Virgo. The first is the supression of infall of near-primordial material, the second is the suppression of radial inflow of metal-poor gas. Distinguishing between the two cases will require more observations of the Virgo cluster spirals and a better understanding of which parameters determine the variation of abundance with radius in field spirals (cf., Garnett & Shields 1987).
Kohli, Nupur; Wright, Karina T.; Sammons, Rachel L.; Jeys, Lee; Snow, Martyn
2015-01-01
Aim To compare the incorporation, growth, and chondrogenic potential of bone marrow (BM) and adipose tissue (AT) mesenchymal stem cells (MSCs) in scaffolds used for cartilage repair. Methods Human BM and AT MSCs were isolated, culture expanded, and characterised using standard protocols, then seeded into 2 different scaffolds, Chondro-Gide or Alpha Chondro Shield. Cell adhesion, incorporation, and viable cell growth were assessed microscopically and following calcein AM/ethidium homodimer (Live/Dead) staining. Cell-seeded scaffolds were treated with chondrogenic inducers for 28 days. Extracellular matrix deposition and soluble glycosaminoglycan (GAG) release into the culture medium was measured at day 28 by histology/immunohistochemistry and dimethylmethylene blue assay, respectively. Results A greater number of viable MSCs from either source adhered and incorporated into Chondro-Gide than into Alpha Chondro Shield. In both cell scaffolds, this incorporation represented less than 2% of the cells that were seeded. There was a marked proliferation of BM MSCs, but not AT MSCs, in Chondro-Gide. MSCs from both sources underwent chondrogenic differentiation following induction. However, cartilaginous extracellular matrix deposition was most marked in Chondro-Gide seeded with BM MSCs. Soluble GAG secretion increased in chondrogenic versus control conditions. There was no marked difference in GAG secretion by MSCs from either cell source. Conclusion Chondro-Gide and Alpha Chondro Shield were permissive to the incorporation and chondrogenic differentiation of human BM and AT MSCs. Chondro-Gide seeded with BM MSCs demonstrated the greatest increase in MSC number and deposition of a cartilaginous tissue. PMID:26425263
Alterations in enamel remineralization in vitro induced by blue light
NASA Astrophysics Data System (ADS)
Kato, I. T.; Zezell, D. M.; Mendes, F. M.; Wetter, N. U.
2010-06-01
Blue light, especially from LED devices, is a very frequently used tool in dental procedures. However, the investigations of its effects on dental enamel are focused primarily on enamel demineralization and fluoride retention. Despite the fact that this spectral region can inhibit enamel demineralization, the effects of the irradiation on demineralized enamel are not known. For this reason, we evaluated the effects of blue LED on remineralization of dental enamel. Artificial lesions were formed in bovine dental enamel blocks by immersing the samples in undersaturated acetate buffer. The lesions were irradiated with blue LED (455 nm, 1.38 W/cm2, 13.75 J/cm2, and 10 s) and remineralization was induced by pH-cycling process. Cross-sectional hardness was used to asses mineral changes after remineralization. Non-irradiated enamel lesions presented higher mineral content than irradiated ones. Furthermore, the mineral content of irradiated group was not significantly different from the lesion samples that were not submitted to the remineralization process. Results obtained in the present study show that the blue light is not innocuous for the dental enamel and inhibition of its remineralization can occur.
Momonoi, Kazumi; Yoshida, Kumi; Mano, Shoji; Takahashi, Hideyuki; Nakamori, Chihiro; Shoji, Kazuaki; Nitta, Akira; Nishimura, Mikio
2009-08-01
Blue color in flowers is due mainly to anthocyanins, and a considerable part of blue coloration can be attributed to metal-complexed anthocyanins. However, the mechanism of metal ion transport into vacuoles and subsequent flower color development has yet to be fully explored. Previously, we studied the mechanism of blue color development specifically at the bottom of the inner perianth in purple tulip petals of Tulipa gesneriana cv. Murasakizuisho. We found that differences in iron content were associated with the development of blue- and purple-colored cells. Here, we identify a vacuolar iron transporter in T. gesneriana (TgVit1), and characterize the localization and function of this transporter protein in tulip petals. The amino acid sequence of TgVit1 is 85% similar that of the Arabidopsis thaliana vacuolar iron transporter AtVIT1, and also showed similarity to the AtVIT1 homolog in yeast, Ca(2+)-sensitive cross-complementer 1 (CCC1). The gene TgVit1 was expressed exclusively in blue-colored epidermal cells, and protein levels increased with increasing mRNA expression and blue coloration. Transient expression experiments revealed that TgVit1 localizes to the vacuolar membrane, and is responsible for the development of the blue color in purple cells. Expression of TgVit1 in yeast rescued the growth defect of ccc1 mutant cells in the presence of high concentrations of FeSO(4). Our results indicate that TgVit1 plays an essential role in blue coloration as a vacuolar iron transporter in tulip petals. These results suggest a new role for involvement of a vacuolar iron transporter in blue flower color development.
30 CFR 75.804 - Underground high-voltage cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... grounded systems shall be equipped with metallic shields around each power conductor with one or more ground conductors having a total cross sectional area of not less than one-half the power conductor, and with an insulated external conductor not smaller than No. 8 (A.W.G.) or an insulated internal ground...
30 CFR 75.804 - Underground high-voltage cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... grounded systems shall be equipped with metallic shields around each power conductor with one or more ground conductors having a total cross sectional area of not less than one-half the power conductor, and with an insulated external conductor not smaller than No. 8 (A.W.G.) or an insulated internal ground...
30 CFR 77.804 - High-voltage trailing cables; minimum design requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... equipped with metallic shields around each power conductor with one or more ground conductors having a total cross-sectional area of not less than one-half the power conductor, and with an insulated conductor for the ground continuity check circuit. External ground check conductors may be used if they are...
A study of heavy-heavy nuclear reactions. [nuclear research/nuclear particles
NASA Technical Reports Server (NTRS)
Khandelwal, G. S.
1975-01-01
Calculations are presented for the reaction products in high energy collisions and of the atmospheric transport of particles such as protons, neutrons and other nucleons. The magnetic moments of charmed baryons are examined. Total cross sections which are required for cosmic heavy ion transport and shielding studies are also examined.
NASA Astrophysics Data System (ADS)
Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela
2016-03-01
The PCA-Replica 12/13 (H2O/Fe) neutron shielding benchmark experiment was analysed using the TORT-3.2 3D SN code. PCA-Replica reproduces a PWR ex-core radial geometry with alternate layers of water and steel including a pressure vessel simulator. Three broad-group coupled neutron/photon working cross section libraries in FIDO-ANISN format with the same energy group structure (47 n + 20 γ) and based on different nuclear data were alternatively used: the ENEA BUGJEFF311.BOLIB (JEFF-3.1.1) and UGENDF70.BOLIB (ENDF/B-VII.0) libraries and the ORNL BUGLE-B7 (ENDF/B-VII.0) library. Dosimeter cross sections derived from the IAEA IRDF-2002 dosimetry file were employed. The calculated reaction rates for the Rh-103(n,n')Rh-103m, In-115(n,n')In-115m and S-32(n,p)P-32 threshold activation dosimeters and the calculated neutron spectra are compared with the corresponding experimental results.
Space radiation shielding studies for astronaut and electronic component risk assessment
NASA Astrophysics Data System (ADS)
Fuchs, Jordan; Gersey, Brad; Wilkins, Richard
The space radiation environment is comprised of a complex and variable mix of high energy charged particles, gamma rays and other exotic species. Elements of this radiation field may also interact with intervening matter (such as a spaceship wall) and create secondary radiation particles such as neutrons. Some of the components of the space radiation environment are highly penetrating and can cause adverse effects in humans and electronic components aboard spacecraft. Developing and testing materials capable of providing effective shielding against the space radiation environment presents special challenges to researchers. Researchers at the Cen-ter for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View AM University (PVAMU) perform accelerator based experiments testing the effectiveness of various materials for use as space radiation shields. These experiments take place at the NASA Space Radiation Laboratory at Brookhaven National Laboratory, the proton synchrotron at Loma Linda University Medical Center, and the Los Alamos Neutron Science Center at Los Alamos National Laboratory where charged particles and neutrons are produced at energies similar to those found in the space radiation environment. The work presented in this paper constitutes the beginning phase of an undergraduate research project created to contribute to this ongoing space radiation shielding project. Specifically, this student project entails devel-oping and maintaining a database of information concerning the historical data from shielding experiments along with a systematic categorization and storage system for the actual shielding materials. The shielding materials referred to here range in composition from standard materi-als such as high density polyethylene and aluminum to exotic multifunctional materials such as spectra-fiber infused composites. The categorization process for each material includes deter-mination of the density thickness of individual samples and a clear labeling and filing method that allows immediate cross referencing with other material samples during the experimental design process. Density thickness measurements will be performed using a precision scale that will allow for the fabrication of sets of standard density thicknesses of selected materials for ready use in shielding experiments. The historical data from previous shielding experiments consists primarily of measurements of absorbed dose, dose equivalent and dose distributions from a Tissue Equivalent Proportional Counter (TEPC) as measured downstream of various thicknesses of the materials while being irradiated in one of the aforementioned particle beams. This data has been digitally stored and linked to the composition of each material and may be easily accessed for shielding effectiveness inter-comparisons. This work was designed to facili-tate and increase the efficiency of ongoing space radiation shielding research performed at the CRESSE as well as serve as a way to educate new generations of space radiation researchers.
NASA Astrophysics Data System (ADS)
Hu, Xiao-Sai; Shen, Yong; Xu, Li-Hui; Wang, Li-Ming; Lu, Li-sha; Zhang, Ya-ting
2016-11-01
The flower-like CuS hierarchical structures were synthesized by solvothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, UV-vis optical absorption spectroscopy and thermogravimetric analysis (TGA). The results demonstrated that the as-prepared flower-like CuS with the diameter of 1-5 um was pure hexagonal phase CuS and had well-defined flower-like structures. (1) The as-prepared CuS was proved to possess high photocatalytic performance with band gap of 1.45 eV. The degradation rate of Methylene blue (MB) was up to, 98.26%, 100% after 30 min under UV and visible irradiation. (2)The UPF of cotton fabric treated with CuS reached up to 174 compared with the original untreated fabric with the UPF 20.62. (3) The electromagnetic interference shielding effectiveness (EMI SE) of CuS coating was up to 27-31 dB when the content of CuS increased to 28.6%wt in the frequency of 300 KHz-3 GHz. Furthermore, the influence of reaction conditions on the morphology of the as-prepared CuS was investigated systematically and the possible formation mechanism of the CuS hierarchical structure was also proposed.
Job demands and health complaints in white and blue collar workers.
Schreuder, K J; Roelen, C A M; Koopmans, P C; Groothoff, J W
2008-01-01
General health in the working population is thought to depend on working conditions. This survey studied job demands and health complaints in working white and blue collar employees. We expect physical and psychological job demands to be differentially distributed among white and blue collar workers. Do they report health complaints consistent with their working conditions? Cross-sectional study of 323 white and 383 blue collar workers. They completed the Basic Occupational Health Questionnaire, a valid and reliable self-report questionnaire about health, work and working conditions. The results were analysed using Chi-square and logistic regression analysis, controlling for educational level as a proxy of socioeconomic status. The questionnaires of 280 white and 251 blue collar workers were suitable for analysis. White collar workers reported higher psychological job demands, and blue collar workers reported higher physical demands. In both occupational groups, low back pain, fatigue and upper respiratory complaints were most common. The rates of low back pain and pain in the lower extremity were higher in blue collar workers, as were regular headaches, pain in the cardiac region and feeling sleepy. However, these relationships substantially weakened when the educational level was adjusted for. Despite the differential distribution of job demands, white and blue collar workers reported similar health complaints. Health in the working population depended predominantly on socioeconomic status. Interventions to improve general health of employees should be directed at their socioeconomic position instead of working conditions.
Clustering of galaxies around AGNs in the HSC Wide survey
NASA Astrophysics Data System (ADS)
Shirasaki, Yuji; Akiyama, Masayuki; Nagao, Tohru; Toba, Yoshiki; He, Wanqiu; Ohishi, Masatoshi; Mizumoto, Yoshihiko; Miyazaki, Satoshi; Nishizawa, Atsushi J.; Usuda, Tomonori
2018-01-01
We have measured the clustering of galaxies around active galactic nuclei (AGNs) for which single-epoch virial masses of the super-massive black hole (SMBH) are available to investigate the relation between the large-scale environment of AGNs and the evolution of SMBHs. The AGN samples used in this work were derived from the Sloan Digital Sky Survey (SDSS) observations and the galaxy samples were from the 240 deg2 S15b data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). The investigated redshift range is 0.6-3.0, and the masses of the SMBHs lie in the range 107.5-1010 M⊙. The absolute magnitude of the galaxy samples reaches to Mλ310 ˜ -18 at rest-frame wavelength 310 nm for the low-redshift end of the samples. More than 70% of the galaxies in the analysis are blue. We found a significant dependence of the cross-correlation length on redshift, which primarily reflects the brightness-dependence of the galaxy clustering. At the lowest redshifts the cross-correlation length increases from 7 h-1 Mpc around Mλ310 = -19 mag to >10 h-1 Mpc beyond Mλ310 = -20 mag. No significant dependence of the cross-correlation length on BH mass was found for whole galaxy samples dominated by blue galaxies, while there was an indication of BH mass dependence in the cross-correlation with red galaxies. These results provides a picture of the environment of AGNs studied in this paper being enriched with blue star-forming galaxies, and a fraction of the galaxies are evolving into red galaxies along with the evolution of SMBHs in that system.
Misnan, Rosmilah; Murad, Shahnaz; Yadzir, Zailatul Hani Mohd; Abdullah, Noormalin
2012-12-01
Tropomyosin and arginine kinase have been identified as the major allergens in multiple species of crab. Charybdis feriatus is an important commercial crab in this country. To characterize the major allergens of C. feriatus using a proteomics approach and subsequently to identify the allergens involved in cross-reactivity with Portunus pelagicus. Raw and boiled extracts of the crabs were prepared from crab meat. The protein profile of the extracts was determined by SDS-PAGE and two-dimensional electrophoresis (2-DE). Major allergens were identified by the immunoblotting test using sera from 50 patients with crab allergy. The major allergens were further identified by 2-DE immunoblotting. The major allergenic spots were then excised, digested by trypsin and identified by mass spectrometry analysis. The immunoblotting inhibition test was performed to study the crossreactivity between red crab and blue crab allergens using sera from 20 patients with allergy to both red and blue crabs. At least 20 protein bands between 13 to 250 kDa were detected in the SDS-PAGE gel of raw extract, while boiled extract procuced fewer protein bands. Proteins of 36 kDa and 41 kDa were recognized as the major allergens of the crab. The major allergenic spot sequences of the 36 and 41 kDa proteins were identified as crab tropomyosin and arginine kinase, respectively. All IgE-binding proteins, including both major allergens, were found to be cross-creative with P. pelagicus allergens. In addition to tropomyosin, arginine kinase was also identified as the major allergen of C. feriatus among our local crab-allergic patients. Cross-reactivity of this crab with P. pelagicus was demonstrated in this study.
A study of lens opacification for a Mars mission
NASA Technical Reports Server (NTRS)
Shinn, J. L.; Wilson, J. W.; Cox, A. B.; Lett, J. T.
1991-01-01
A method based on risk-related cross sections is used to estimate risks of 'stationary' cataracts caused by radiation exposures during extended missions in deep space. Estimates of the even more important risk of late degenerative cataractogenesis are made on the basis of the limited data available. Data on lenticular opacification in the New Zealand white rabbit, an animal model from which such results can be extrapolated to humans, are analyzed by the Langley cosmic ray shielding code (HZETRN) to generate estimates of stationary cataract formation resulting from a Mars mission. The effects of the composition of shielding material and the relationship between risk and LET are given, and the effects of target fragmentation on the risk coefficients are evaluated explicitly.
Studies of HZE particle interactions and transport for space radiation protection purposes
NASA Technical Reports Server (NTRS)
Townsend, Lawrence W.; Wilson, John W.; Schimmerling, Walter; Wong, Mervyn
1987-01-01
The main emphasis is on developing general methods for accurately predicting high-energy heavy ion (HZE) particle interactions and transport for use by researchers in mission planning studies, in evaluating astronaut self-shielding factors, and in spacecraft shield design and optimization studies. The two research tasks are: (1) to develop computationally fast and accurate solutions to the Boltzmann (transport) equation; and (2) to develop accurate HZE interaction models, from fundamental physical considerations, for use as inputs into these transport codes. Accurate solutions to the HZE transport problem have been formulated through a combination of analytical and numerical techniques. In addition, theoretical models for the input interaction parameters are under development: stopping powers, nuclear absorption cross sections, and fragmentation parameters.
Aging reduces the stimulating effect of blue light on cognitive brain functions.
Daneault, Véronique; Hébert, Marc; Albouy, Geneviève; Doyon, Julien; Dumont, Marie; Carrier, Julie; Vandewalle, Gilles
2014-01-01
Light exposure, particularly blue light, is being recognized as a potent mean to stimulate alertness and cognition in young individuals. Aging is associated with changes in alertness regulation and cognition. Whether the effect of light on cognitive brain function changes with aging is unknown, however. Cross-sectional study. Functional Neuroimaging Unit, University of Montreal Geriatric Institute. Sixteen younger (23 ± 4.1 y) and 14 older (61 ± 4.5 y) healthy participants were recruited in the current study. Blue light administration. We used functional magnetic resonance imaging to record brain responses to an auditory working memory task in young and older healthy individuals, alternatively maintained in darkness or exposed to blue light. Results show that the older brain remains capable of showing sustained responses to light in several brain areas. However, compared to young individuals, the effect of blue light is decreased in the pulvinar, amygdala, and tegmentum as well as in the insular, prefrontal, and occipital cortices in elderly individuals. The effect of blue light on brain responses diminishes with aging in areas typically involved in visual functions and in key regions for alertness regulation and higher executive processes. Our findings provide the first indications that the effect of light on cognition may be reduced in healthy aging.
Progress on China nuclear data processing code system
NASA Astrophysics Data System (ADS)
Liu, Ping; Wu, Xiaofei; Ge, Zhigang; Li, Songyang; Wu, Haicheng; Wen, Lili; Wang, Wenming; Zhang, Huanyu
2017-09-01
China is developing the nuclear data processing code Ruler, which can be used for producing multi-group cross sections and related quantities from evaluated nuclear data in the ENDF format [1]. The Ruler includes modules for reconstructing cross sections in all energy range, generating Doppler-broadened cross sections for given temperature, producing effective self-shielded cross sections in unresolved energy range, calculating scattering cross sections in thermal energy range, generating group cross sections and matrices, preparing WIMS-D format data files for the reactor physics code WIMS-D [2]. Programming language of the Ruler is Fortran-90. The Ruler is tested for 32-bit computers with Windows-XP and Linux operating systems. The verification of Ruler has been performed by comparison with calculation results obtained by the NJOY99 [3] processing code. The validation of Ruler has been performed by using WIMSD5B code.
An Improved Elastic and Nonelastic Neutron Transport Algorithm for Space Radiation
NASA Technical Reports Server (NTRS)
Clowdsley, Martha S.; Wilson, John W.; Heinbockel, John H.; Tripathi, R. K.; Singleterry, Robert C., Jr.; Shinn, Judy L.
2000-01-01
A neutron transport algorithm including both elastic and nonelastic particle interaction processes for use in space radiation protection for arbitrary shield material is developed. The algorithm is based upon a multiple energy grouping and analysis of the straight-ahead Boltzmann equation by using a mean value theorem for integrals. The algorithm is then coupled to the Langley HZETRN code through a bidirectional neutron evaporation source term. Evaluation of the neutron fluence generated by the solar particle event of February 23, 1956, for an aluminum water shield-target configuration is then compared with MCNPX and LAHET Monte Carlo calculations for the same shield-target configuration. With the Monte Carlo calculation as a benchmark, the algorithm developed in this paper showed a great improvement in results over the unmodified HZETRN solution. In addition, a high-energy bidirectional neutron source based on a formula by Ranft showed even further improvement of the fluence results over previous results near the front of the water target where diffusion out the front surface is important. Effects of improved interaction cross sections are modest compared with the addition of the high-energy bidirectional source terms.
NASA Technical Reports Server (NTRS)
Lin, Z. W.; Adams, J. H., Jr.
2006-01-01
The radiation hazard for astronauts from galactic cosmic rays is a major obstacle in long duration human space explorations. Space radiation transport codes have been developed to calculate radiation environment on missions to the Moon, Mars or beyond. We have studied how uncertainties in fragmentation cross sections at different energies affect the accuracy of predictions from such radiation transport. We find that, in deep space, cross sections between 0.3 and 0.85 GeV/u usually have the largest effect on dose-equivalent behind shielding in solar minimum GCR environments, and cross sections between 0.85 and 1.2 GeV/u have the largest effect in solar maximum GCR environments. At the International Space Station, cross sections at higher energies have the largest effect due to the geomagnetic cutoff.
The Development and Application of Novel Methods for the Solution of EMP Shielding Problems.
1981-02-01
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The Blue Arc Entoptic Phenomenon in Glaucoma (An American Ophthalmological Thesis)
Pasquale, Louis R.; Brusie, Steven
2013-01-01
Purpose: To determine whether the blue arc entoptic phenomenon, a positive visual response originating from the retina with a shape that conforms to the topology of the nerve fiber layer, is depressed in glaucoma. Methods: We recruited a cross-sectional, nonconsecutive sample of 202 patients from a single institution in a prospective manner. Subjects underwent full ophthalmic examination, including standard automated perimetry (Humphrey Visual Field 24–2) or frequency doubling technology (Screening C 20–5) perimetry. Eligible patients viewed computer-generated stimuli under conditions chosen to optimize perception of the blue arcs. Unmasked testers instructed patients to report whether they were able to perceive blue arcs but did not reveal what response was expected. We created multivariable logistic regression models to ascertain the demographic and clinical parameters associated with perceiving the blue arcs. Results: In multivariable analyses, each 0.1 unit increase in cup-disc ratio was associated with 36% reduced likelihood of perceiving the blue arcs (odds ratio [OR] = 0.66 [95% confidence interval (CI): 0.53–0.83], P<.001). A smaller mean defect was associated with an increased likelihood of perceiving the blue arcs (OR=1.79 [95% CI: 1.40–2.28]); P<.001), while larger pattern standard deviation (OR=0.72 [95% CI: 0.57–0.91]; P=.005) and abnormal glaucoma hemifield test (OR=0.25 [0.10–0.65]; P=.006) were associated with a reduced likelihood of perceiving them. Older age and media opacity were also associated with an inability to perceive the blue arcs. Conclusion: In this study, the inability to perceive the blue arcs correlated with structural and functional features associated with glaucoma, although older age and media opacity were also predictors of this entoptic response. PMID:24167324
The blue arc entoptic phenomenon in glaucoma (an American ophthalmological thesis).
Pasquale, Louis R; Brusie, Steven
2013-09-01
To determine whether the blue arc entoptic phenomenon, a positive visual response originating from the retina with a shape that conforms to the topology of the nerve fiber layer, is depressed in glaucoma. We recruited a cross-sectional, nonconsecutive sample of 202 patients from a single institution in a prospective manner. Subjects underwent full ophthalmic examination, including standard automated perimetry (Humphrey Visual Field 24-2) or frequency doubling technology (Screening C 20-5) perimetry. Eligible patients viewed computer-generated stimuli under conditions chosen to optimize perception of the blue arcs. Unmasked testers instructed patients to report whether they were able to perceive blue arcs but did not reveal what response was expected. We created multivariable logistic regression models to ascertain the demographic and clinical parameters associated with perceiving the blue arcs. In multivariable analyses, each 0.1 unit increase in cup-disc ratio was associated with 36% reduced likelihood of perceiving the blue arcs (odds ratio [OR] = 0.66 [95% confidence interval (CI): 0.53-0.83], P<.001). A smaller mean defect was associated with an increased likelihood of perceiving the blue arcs (OR=1.79 [95% CI: 1.40-2.28]); P<.001), while larger pattern standard deviation (OR=0.72 [95% CI: 0.57-0.91]; P=.005) and abnormal glaucoma hemifield test (OR=0.25 [0.10-0.65]; P=.006) were associated with a reduced likelihood of perceiving them. Older age and media opacity were also associated with an inability to perceive the blue arcs. In this study, the inability to perceive the blue arcs correlated with structural and functional features associated with glaucoma, although older age and media opacity were also predictors of this entoptic response.
Gerothanassis, I. P.; Momenteau, M.; Barrie, P. J.; Kalodimos, C. G.; Hawkes, G. E.
1996-04-24
13C cross-polarization magic-angle-spinning (CP/MAS) NMR spectra of several carbonmonoxide (93-99% (13)C enriched) hemoprotein models with 1,2-dimethylimidazole (1,2-diMeIm) and 1-methylimidazole (1-MeIm) as axial ligands are reported. This enables the (13)CO spinning sideband manifold to be measured and hence the principal components of the (13)CO chemical shift tensor to be obtained. Negative polar interactions in the binding pocket of the cap porphyrin model and inhibition of Fe-->CO back-donation result in a reduction in shielding anisotropy; on the contrary, positive distal polar interactions result in an increase in the shielding anisotropy and asymmetry parameter in some models. It appears that the axial hindered base 1,2-dimethylimidazole has little direct effect on the local geometry at the CO site, despite higher rates of CO desorption being observed for such complexes. This suggests that the mechanism by which steric interactions are released for the 1,2-diMeIm complexes compared to 1-MeIm complexes does not involve a significant increase in bending of the Fe-C-O unit. The asymmetry of the shielding tensor of all the heme model compounds studied is smaller than that found for horse myoglobin and rabbit hemoglobin.
The Effects of Plasma Shield on the Radar Cross Section of a Generic Missile in UHF Band
NASA Astrophysics Data System (ADS)
Chung, Shen
2011-10-01
RF Stealth is the dominant technology in today's military aircraft, and most is achieved by shape design with a few reductions achieved by RAM, but most of these effects are only valid in X band. With the popularity of UHF radar again rising, the possibility of detecting a stealth object has increased due to resonance effect, and this is difficult to decrease with previous means due to the long wavelength. A plasma shield generated in front of an object may be suitable to alter the RCS in specific band without physically changing its shape. We examine the RCS of a generic missile in UHF band, and compared it with one with a cone-shape plasma generated in front of the missile. We find the plasma effectively changes the RCS of the missile, though not necessarily smaller. The RCS of the missile with the plasma shield is now dominated by the plasma instead of the missile. The RCS is a function of the size, shape, and density of the plasma shield. For higher frequency signals like the X band radar, it can still penetrate the plasma, and sees the original RCS of the missile. Due to the relatively lower UHF frequency, the plasma density needed is lower than one in X band and thus more practical to achieve.
Terrestrial Background Reduction in RPM Systems by Direct Internal Shielding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, Sean M.; Ashbaker, Eric D.; Schweppe, John E.
2008-11-19
Gamma-ray detection systems that are close to the earth or other sources of background radiation often require shielding, especially when trying to detect a relatively weak source. One particular case of interest that we address in this paper is that encountered by the Radiation Portal Monitors (RPMs) systems placed at border-crossing Ports of Entry (POE). These RPM systems are used to screen for illicit radiological materials, and they are often placed in situations where terrestrial background is large. In such environments, it is desirable to consider simple physical modifications that could be implemented to reduce the effects from background radiationmore » without affecting the flow of traffic and the normal operation of the portal. Simple modifications include adding additional shielding to the environment, either inside or outside the apparatus. Previous work [2] has shown the utility of some of these shielding configurations for increasing the Signal to Noise Ratio (SNR) of gross-counting RPMs. Because the total cost for purchasing and installing RPM systems can be quite expensive, in the range of hundreds of thousands of dollars for each cargo-screening installation, these shielding variations may offer increases in detection capability for relatively small cost. Several modifications are considered here in regard to their real-world applicability, and are meant to give a general idea of the effectiveness of the schemes used to reduce background for both gross-counting and spectroscopic detectors. These scenarios are modeled via the Monte-Carlo N-Particle (MCNP) code package [1] for ease of altering shielding configurations, as well as enacting unusual scenarios prior to prototyping in the field. The objective of this paper is to provide results representative of real modifications that could enhance the sensitivity of this, as well as the next generation of radiation detectors. The models used in this work were designed to provide the most general results for an RPM. These results are therefore presented as general guidance on what shielding configurations will be the most valuable for a generalized RPM, considered in light of their economic and geometric possibility in the real world.« less
Radiation Transport and Shielding for Space Exploration and High Speed Flight Transportation
NASA Technical Reports Server (NTRS)
Maung, Khin Maung; Trapathi, R. K.
1997-01-01
Transportation of ions and neutrons in matter is of direct interest in several technologically important and scientific areas, including space radiation, cosmic ray propagation studies in galactic medium, nuclear power plants and radiological effects that impact industrial and public health. For the proper assessment of radiation exposure, both reliable transport codes and accurate data are needed. Nuclear cross section data is one of the essential inputs into the transport codes. In order to obtain an accurate parametrization of cross section data, theoretical input is indispensable especially for processes where there is little or no experimental data available. In this grant period work has been done on the studies of the use of relativistic equations and their one-body limits. The results will be useful in choosing appropriate effective one-body equation for reaction calculations. Work has also been done to improve upon the data base needed for the transport codes used in the studies of radiation transport and shielding for space exploration and high speed flight transportation. A phenomenological model was developed for the total absorption cross sections valid for any system of charged and/or uncharged collision pairs for the entire energy range. The success of the model is gratifying. It is being used by other federal agencies, national labs and universities. A list of publications based on the work during the grant period is given below and copies are enclosed with this report.
Development of Naphthalene PLIF for Visualizing Ablation Products From a Space Capsule Heat Shield
NASA Technical Reports Server (NTRS)
Combs, C. S.; Clemens, N. T.; Danehy, P. M.
2014-01-01
The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield. To better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process would be beneficial. Here, a technique developed at The University of Texas at Austin that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to enable visualization of the ablation products in a hypersonic flow is applied. Although high-temperature ablation is difficult and expensive to recreate in a laboratory environment, low-temperature sublimation creates a limited physics problem that can be used to explore ablation-product transport in a hypersonic flow-field. In the current work, a subscale capsule reentry vehicle model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel. The PLIF technique provides images of the spatial distribution of sublimated naphthalene in the heat-shield boundary layer, separated shear layer, and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. PLIF images have shown high concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure. It was shown that, in general, the capsule shear layer appears to be more unsteady at lower angels of attack. The PLIF images demonstrated that during a wind tunnel run, as the model heated up, the rate of naphthalene ablation increased, since the PLIF signal increased steadily over the course of a run. Additionally, the shear layer became increasingly unsteady over the course of a wind tunnel run, likely because of increased surface roughness but also possibly because of the increased blowing. Regions with a relatively low concentration of naphthalene were also identified in the capsule backshell recirculation region and are most likely the result of cross-flow-induced vortices on the capsule afterbody.
Rolland, Jennifer M; Varese, Nirupama P; Abramovitch, Jodie B; Anania, Jessica; Nugraha, Roni; Kamath, Sandip; Hazard, Anita; Lopata, Andreas L; O'Hehir, Robyn E
2018-05-14
Shellfish allergy is an increasing global health priority, frequently affecting adults. Molluscs are an important shellfish group causing food allergy but knowledge of their allergens and cross-reactivity is limited. Optimal diagnosis of mollusc allergy enabling accurate advice on food avoidance is difficult. We characterized allergens of four frequently ingested Asia-Pacific molluscs: Sydney Rock Oyster (Saccostrea glomerata), Blue Mussel (Mytilus edulis), Saucer Scallop (Amusium balloti) and Southern Calamari (Sepioteuthis australis), examining cross-reactivity between species and with Blue Swimmer Crab tropomyosin, Por p 1. IgE ELISA showed that cooking increased IgE reactivity of mollusc extracts and basophil activation confirmed biologically relevant IgE reactivity. Immunoblotting demonstrated strong IgE reactivity of several proteins including one corresponding to heat-stable tropomyosin in all species (37-40 kDa). IgE-reactive Sydney Rock Oyster proteins were identified by mass spectrometry, and the novel major oyster tropomyosin allergen was cloned, sequenced and designated Sac g 1 by the IUIS. Oyster extracts showed highest IgE cross-reactivity with other molluscs, while mussel cross-reactivity was weakest. Inhibition immunoblotting demonstrated high cross-reactivity between tropomyosins of mollusc and crustacean species. These findings inform novel approaches for reliable diagnosis and improved management of mollusc allergy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Erren, T C; Erren, M; Lerchl, A; Meyer-Rochow, V B
2008-04-01
This paper presents a hypothesis that could explain why blue light appears to dominate non-image-forming (NIF) ocular photoreception in marine as well as terrestrial vertebrates. Indeed, there is more and more evidence suggesting that 'novel' retinal photoreceptors, which are sensitive to blue light and were only discovered in the 1990s, could be a feature shared by all vertebrates. In our view, blue light photoreception evolved and persisted as NIF photoreception because it has been useful in the colonisation of extensive photo-dependent oceanic habitats and facilitated the move of vertebrates from an aquatic to a terrestrial environment. Because the available scattered evidence is compatible with the validity of our hypothesis, we hope that our rationale will be followed up. Indeed, it (1) involves testable predictions, (2) provides plausible explanations for previous observations, (3) unites phenomena not previously considered related to one another and (4) suggests tests that have not been carried out before. Overall, our approach not only embraces cross-disciplinary links; it, moreover, serves as a reminder of an all-embracing evolutionary history, especially with regard to a ubiquitous photoreceptive 'clockwork-blue' in marine and terrestrial vertebrates.
Two-step excitation and blue fluorescence under continuous-wave pumping in Nd:YLF
NASA Technical Reports Server (NTRS)
Fan, T. Y.; Byer, Robert L.
1986-01-01
Near-UV and blue fluorescence from the 4D3/2 and 4D5/2 manifolds in Nd:YLF has been observed at room temperature under CW pumping by a rhodamine 590 dye laser. Excitation to these manifolds is attributed to two-step excitation involving excited-state absorption from the 4F3/2 metastable level. A similar phenomenon has also been observed in Nd:YAG and Nd:glass. The effective excited-state absorption cross section is measured to be (2 + or - 1) x 10 to the -20th sq cm at 587.4 nm in the pi polarization, and the peak effective stimulated emission cross section is measured to be 5 x 10 to the -20th sq cm at 411.7 nm, also in the pi polarization. Estimated laser threshold at 411.7 nm for two-step pumping at 587.4 nm is 70 mW.
On the luminosity function, lifetimes, and origin of blue stragglers in globular clusters
NASA Technical Reports Server (NTRS)
Bailyn, Charles D.; Pinsonneault, Marc H.
1995-01-01
We compute theoretical evolutionary tracks of blue stragglers created by mergers. Two formation scenarios are considered: mergers of primordial binaries, and stellar collisions. These two scenarios predict strikingly different luminosity functions, which are potentially distinguishable observationally. Tabulated theoretical luminosity functions and lifetimes are presented for blue stragglers formed under a variety of input conditions. We compare our results with observations of the blue straggler sequences in 47 Tucanae and M3. In the case of 47 Tuc, the luminosity function and the formation rate are compatible with the hypothesis that the blue stragglers formed through the collision of single stars. Mergers of primordial binaries are only marginally cosistent with the data, and a significant enhancement of the collision cross section by binary-single-star encounters appears to be ruled out. In the case of M3, we find that the innermost blue stragglers have a luminosity function significantly different from that of the outer stragglers, thus confirming earlier suggestions that there are two distinct populations of blue stragglers in this cluster. The inner stragglers are preferentially brighter and bluer, as would be expected if they were made by collisions, but there are so many of them that the collision rate would need to be enhanced by interactions involving wide binaries. The luminosity function of the outer stragglers is almost identical to the predictions of mergers from primordial binaries and is inconsistent with the collision hypothesis.
Multifocal blue-on-yellow visual evoked potentials in early glaucoma.
Klistorner, Alexander; Graham, Stuart L; Martins, Alessandra; Grigg, John R; Arvind, Hemamalini; Kumar, Rajesh S; James, Andrew C; Billson, Francis A
2007-09-01
To determine the sensitivity and specificity of blue-on-yellow multifocal visual evoked potentials (mfVEPs) in early glaucoma. Cross-sectional study. Fifty patients with a confirmed diagnosis of early glaucoma and 60 normal participants. Black-and-white mfVEPs and blue-on-yellow mfVEPs were recorded using the Accumap version 2.0 (ObjectiVision Pty. Ltd., Sydney, Australia). All patients also underwent achromatic standard automated perimetry (SAP). Multifocal VEP amplitude and latency values in glaucoma patients were analyzed and compared with those of the normal controls. Based on the definition of visual field defect, in the group of glaucomatous eyes with SAP defects, amplitude of blue-on-yellow mfVEP was abnormal in all 64 cases (100% sensitivity), whereas black-and-white mfVEP missed 5 cases (92.2% sensitivity). Generally, larger scotomata were noted on blue-on-yellow mfVEP compared with black-and-white mfVEP for the same eyes. There was high topographic correspondence between SAP and amplitude of blue-on-yellow mfVEP and significant (P<0.0001) correlation between them (correlation coefficient, 0.73). Abnormal amplitude was detected in 3 of 60 eyes of control subjects (95% specificity). There was, however, no correlation between visual field defect and latency delay in glaucoma patients. Although there was a significant difference between averaged latency of control and glaucoma eyes, values considerably overlapped. The blue-on-yellow mfVEP is a sensitive and specific tool for detecting early glaucoma based on amplitude analysis.
The Najd Fault System of Saudi Arabia
NASA Astrophysics Data System (ADS)
Stüwe, Kurt; Kadi, Khalid; Abu-Alam, Tamer; Hassan, Mahmoud
2014-05-01
The Najd Fault System of the Arabian-Nubian Shield is considered to be the largest Proterozoic Shear zone system on Earth. The shear zone was active during the late stages of the Pan African evolution and is known to be responsible for the exhumation of fragments of juvenile Proterozoic continental crust that form a series of basement domes across the shield areas of Egypt and Saudi Arabia. A three year research project funded by the Austrian Science Fund (FWF) and supported by the Saudi Geological Survey (SGS) has focused on structural mapping, petrology and geochronology of the shear zone system in order to constrain age and mechanisms of exhumation of the domes - with focus on the Saudi Arabian side of the Red Sea. We recognise important differences in comparison with the basement domes in the Eastern desert of Egypt. In particular, high grade metamorphic rocks are not exclusively confined to basement domes surrounded by shear zones, but also occur within shear zones themselves. Moreover, we recognise both exhumation in extensional and in transpressive regimes to be responsible for exhumation of high grade metamorphic rocks in different parts of the shield. We suggest that these apparent structural differences between different sub-regions of the shield largely reflect different timing of activity of various branches of the Najd Fault System. In order to tackle the ill-resolved timing of the Najd Fault System, zircon geochronology is performed on intrusive rocks with different cross cutting relationships to the shear zone. We are able to constrain an age between 580 Ma and 605 Ma for one of the major branches of the shear zone, namely the Ajjaj shear zone. In our contribution we present a strain map for the shield as well as early geochronological data for selected shear zone branches.
Bachtel, Andrew D; Gray, Richard A; Stohlman, Jayna M; Bourgeois, Elliot B; Pollard, Andrew E; Rogers, Jack M
2011-07-01
We developed a new method for ratiometric optical mapping of transmembrane potential (V(m)) in cardiac preparations stained with di-4-ANEPPS. V(m)-dependent shifts of excitation and emission spectra establish two excitation bands (<481 and >481 nm) that produce fluorescence changes of opposite polarity within a single emission band (575-620 nm). The ratio of these positive and negative fluorescence signals (excitation ratiometry) increases V(m) sensitivity and removes artifacts common to both signals. We pulsed blue (450 ± 10 nm) and cyan (505 ± 15 nm) light emitting diodes (LEDs) at 375 Hz in alternating phase synchronized to a camera (750 frames-per-second). Fluorescence was bandpass filtered (585 ± 20 nm). This produced signals with upright (blue) and inverted (cyan) action potentials (APs) interleaved in sequential frames. In four whole swine hearts with motion chemically arrested, fractional fluorescence for blue, cyan, and ratio signals was 1.2 ± 0.3%, 1.2 ± 0.3%, and 2.4 ± 0.6%, respectively. Signal-to-noise ratios were 4.3 ± 1.4, 4.0 ± 1.2, and 5.8 ± 1.9, respectively. After washing out the electromechanical uncoupling agent, we characterized motion artifact by cross-correlating blue, cyan, and ratio signals with a signal with normal AP morphology. Ratiometry improved cross-correlation coefficients from 0.50 ± 0.48 to 0.81 ± 0.25, but did not cancel all motion artifacts. These findings demonstrate the feasibility of pulsed LED excitation ratiometry in myocardium. © 2011 IEEE
Bachtel, Andrew D.; Gray, Richard A.; Stohlman, Jayna M.; Bourgeois, Elliot B.; Pollard, Andrew E.
2011-01-01
We developed a new method for ratiometric optical mapping of transmembrane potential (Vm) in cardiac preparations stained with di-4-ANEPPS. Vm-dependent shifts of excitation and emission spectra establish two excitation bands (<481 and >481 nm) that produce fluorescence changes of opposite polarity within a single emission band (575–620 nm). The ratio of these positive and negative fluorescence signals (excitation ratiometry) increases Vm sensitivity and removes artifacts common to both signals. We pulsed blue (450±10 nm) and cyan (505±15 nm) light emitting diodes (LEDs) at 375 Hz in alternating phase synchronized to a camera (750 frames-per-second). Fluorescence was bandpass filtered (585±20 nm). This produced signals with upright (blue) and inverted (cyan) action potentials (APs) interleaved in sequential frames. In 4 whole swine hearts with motion chemically arrested, fractional fluorescence for blue, cyan, and ratio signals was 1.2±0.3%, 1.2±0.3%, and 2.4±0.6%, respectively. Signal-to-noise ratios were 4.3±1.4, 4.0±1.2, and 5.8±1.9, respectively. After washing out the electromechanical uncoupling agent, we characterized motion artifact by cross-correlating blue, cyan, and ratio signals with a signal with normal AP morphology. Ratiometry improved cross-correlation coefficients from 0.50±0.48 to 0.81±0.25, but did not cancel all motion artifacts. These findings demonstrate the feasibility of pulsed LED excitation ratiometry in myocardium. PMID:21536528
Tooth whitening evaluation of blue covarine containing toothpastes.
Tao, Danying; Smith, Richard N; Zhang, Qiong; Sun, Jianing N; Philpotts, Carole J; Ricketts, Stephen R; Naeeni, Mojgan; Joiner, Andrew
2017-12-01
To measure the tooth whitening effects delivered immediately after brushing with silica-based toothpastes containing blue covarine in vitro and in vivo. Salivary pellicle coated human extracted teeth were brushed with either a slurry of a toothpaste containing blue covarine (BC), a formulation containing an increased level of blue covarine (BC+) or a negative control toothpaste containing no blue covarine. The colour of the specimens were measured in vitro using either a Minolta chromameter or a VITA Easyshade spectrophotometer, before and after brushing and changes in CIELAB values and tooth Whiteness Index (WIO) values calculated. In a double-blind cross-over clinical study, subjects brushed with either BC or BC+ toothpaste and tooth colour changes were measured with a digital image analysis system. The in vitro studies demonstrated that toothpastes containing blue covarine gave a significantly (p<0.05) greater change in b* and WIO values than the negative control toothpaste; the BC+ toothpaste gave a significantly greater increase in b* and WIO values than the BC toothpaste, and BC+ gave a significant increase in shade change versus the negative control. Clinical results showed that BC and BC+ gave a significant reduction in b* (p<0.0001) and increase in WIO (p<0.0001) from baseline indicating significant tooth whitening had occurred. The parameter changes were significantly greater when brushing with the BC+ toothpaste than with the BC toothpaste (WIO p=0.006; b* p=0.013). Toothpastes containing blue covarine gave a statistically significant reduction in tooth yellowness and improvement in tooth whiteness immediately after brushing in both in vitro and clinical studies. In addition, the higher concentration blue covarine toothpaste gave statistically significant greater tooth whitening benefits than the lower concentration blue covarine toothpaste. The silica-based toothpastes containing blue covarine evaluated in the current study gave tooth whitening benefits immediately after one brush. Copyright © 2017 Elsevier Ltd. All rights reserved.
NUCFRG2: An evaluation of the semiempirical nuclear fragmentation database
NASA Technical Reports Server (NTRS)
Wilson, J. W.; Tripathi, R. K.; Cucinotta, F. A.; Shinn, J. L.; Badavi, F. F.; Chun, S. Y.; Norbury, J. W.; Zeitlin, C. J.; Heilbronn, L.; Miller, J.
1995-01-01
A semiempirical abrasion-ablation model has been successful in generating a large nuclear database for the study of high charge and energy (HZE) ion beams, radiation physics, and galactic cosmic ray shielding. The cross sections that are generated are compared with measured HZE fragmentation data from various experimental groups. A research program for improvement of the database generator is also discussed.
Benchmarked analyses of gamma skyshine using MORSE-CGA-PC and the DABL69 cross-section set
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reichert, P.T.; Golshani, M.
1991-01-01
Design for gamma-ray skyshine is a common consideration for a variety of nuclear and accelerator facilities. Many of these designs can benefit from a more accurate and complete treatment than can be provided by simple skyshine analysis tools. Those methods typically require a number of conservative, simplifying assumptions in modeling the radiation source and shielding geometry. This paper considers the benchmarking of one analytical option. The MORSE-CGA Monte Carlo radiation transport code system provides the capability for detailed treatment of virtually any source and shielding geometry. Unfortunately, the mainframe computer costs of MORSE-CGA analyses can prevent cost-effective application to smallmore » projects. For this reason, the MORSE-CGA system was converted to run on IBM personal computer (PC)-compatible computers using the Intel 80386 or 80486 microprocessors. The DLC-130/DABL69 cross-section set (46n,23g) was chosen as the most suitable, readily available, broad-group library. The most important reason is the relatively high (P{sub 5}) Legendre order of expansion for angular distribution. This is likely to be beneficial in the deep-penetration conditions modeled in some skyshine problems.« less
CENSUS OF BLUE STARS IN SDSS DR8
Scibelli, Samantha; Newberg, Heidi Jo; Carlin, Jeffrey L.; ...
2014-12-02
In this work, we present a census of the 12,060 spectra of blue objects (more » $$(g-r)_0<-0.25$$) in the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). As part of the data release, all of the spectra were cross-correlated with 48 template spectra of stars, galaxies and QSOs to determine the best match. We compared the blue spectra by eye to the templates assigned in SDSS DR8. 10,856 of the objects matched their assigned template, 170 could not be classified due to low signal-to-noise (S/N), and 1034 were given new classifications. We identify 7458 DA white dwarfs, 1145 DB white dwarfs, 273 rarer white dwarfs (including carbon, DZ, DQ, and magnetic), 294 subdwarf O stars, 648 subdwarf B stars, 679 blue horizontal branch stars, 1026 blue stragglers, 13 cataclysmic variables, 129 white dwarf - M dwarf binaries, 36 objects with spectra similar to DO white dwarfs, 179 QSOs, and 10 galaxies. We provide two tables of these objects, sample spectra that match the templates, figures showing all of the spectra that were grouped by eye, and diagnostic plots that show the positions, colors, apparent magnitudes, proper motions, etc. for each classification. In conclusion, future surveys will be able to use templates similar to stars in each of the classes we identify to classify blue stars, including rare types, automatically.« less
Geologic mapping of Northern Atla Regio on Venus: Preliminary data
NASA Technical Reports Server (NTRS)
Nikishin, A. M.; Burba, G. A.
1993-01-01
The Northern part of Atla Regio within the frame of C1-formate Magellan photo map 15N197 was mapped geologically at scale 1:8,000,000. This is a part of Russia's contribution into C1 geologic mapping efforts. The map is reproduced here being reduced about twice. The map shows that the Northern Atla area is predominantly a volcanic plain with numerous volcanic features: shield volcanoes, domes and hills with various morphology, corona-like constructions, radar bright and dark spots often with flow-like outlines. Relatively small areas of tessera occurred in the area are mainly semi-flooded with the plain material. Tesserae are considered to be the oldest terrains within the map sheet. There are many lineated terrains in the region. They are interpreted as the old, almost-buried tesserae (those with crossed lineaments) or partly buried ridge belts (those with parallel lineaments). These lineated terrains have an intermediate age between the young volcanic plains and the old tessera areas. Two prominent high volcanic shields are located within the region - Ozza Mons and Sapas Mona. The most prominent structure in Northern Atla is Ganis Chasma rift. The rift cuts volcanic plain and is considered to be under formation during approximately the same time with Ozza Mons shield. Ganis Chasma rift valley is highly fractured and bounded with fault scarps. Rift shoulder uplifts are typical for Ganis Chasma. There are few relatively young volcanic features inside the rift valley. The analysis of fracturing and rift valley geometry shows the rift originated due to 5-10 percent crustal extention followed by the crustal subsidence. The age sequence summary for the main terrain types in the region is (from older to younger ones): tesserae; lineated terrains with crossed lineaments; lineated terrains with parallel lineaments; volcanic plains; and prominent volcanic shields and Ganis Chasma rift valley. The geologic structure of Atla Regio as it appeared now with the Magellan high resolution images is very close to that of Beta Regio. Such conclusion coincide with the earlier ones based on the coarser data.
Volcano morphometry and volume scaling on Venus
NASA Technical Reports Server (NTRS)
Garvin, J. B.; Williams, R. S., Jr.
1994-01-01
A broad variety of volcanic edifices have been observed on Venus. They ranged in size from the limits of resolution of the Magellan SAR (i.e., hundreds of meters) to landforms over 500 km in basal diameter. One of the key questions pertaining to volcanism on Venus concerns the volume eruption rate or VER, which is linked to crustal productivity over time. While less than 3 percent of the surface area of Venus is manifested as discrete edifices larger than 50 km in diameter, a substantial component of the total crustal volume of the planet over the past 0.5 Ga is related to isolated volcanoes, which are certainly more easily studied than the relatively diffusely defined plains volcanic flow units. Thus, we have focused our efforts on constraining the volume productivity of major volcanic edifices larger than 100 km in basal diameter. Our approach takes advantage of the topographic data returned by Magellan, as well as our database of morphometric statistics for the 20 best known lava shields of Iceland, plus Mauna Loa of Hawaii. As part of this investigation, we have quantified the detailed morphometry of nearly 50 intermediate to large scale edifices, with particular attention to their shape systematics. We found that a set of venusian edifices which include Maat, Sapas, Tepev, Sif, Gula, a feature at 46 deg S, 215 deg E, as well as the shield-like structure at 10 deg N, 275 deg E are broadly representative of the approx. 400 volcanic landforms larger than 50 km. The cross-sectional shapes of these 7 representative edifices range from flattened cones (i.e., Sif) similar to classic terrestrial lava shields such as Mauna Loa and Skjaldbreidur, to rather dome-like structures which include Maat and Sapas. The majority of these larger volcanoes surveyed as part of our study displayed cross-sectional topographies with paraboloidal shaped, in sharp contrast with the cone-like appearance of most simple terrestrial lava shields. In order to more fully explore the differences between large venusian edifices and volcanoes on the Earth and Mars, we developed a volume scaling algorithm which relies on conservation of volcano morphometry as basal diameter is varied.
NASA Astrophysics Data System (ADS)
Gaskell, C. Martin
2017-05-01
Low-redshift active galactic nuclei (AGNs) with extremely blue optical spectral indices are shown to have a mean, velocity-averaged, broad-line Hα/Hβ ratio of ≈2.72 ± 0.04, consistent with a Baker-Menzel Case B value. Comparison of a wide range of properties of the very bluest AGNs with those of a luminosity-matched subset of the Dong et al. blue AGN sample indicates that the only difference is the internal reddening. Ultraviolet fluxes are brighter for the bluest AGNs by an amount consistent with the flat AGN reddening curve of Gaskell et al. The lack of a significant difference in the GALEX (far-ultraviolet-near-ultraviolet) colour index strongly rules out a steep Small Magellanic Cloud-like reddening curve and also argues against an intrinsically harder spectrum for the bluest AGNs. For very blue AGNs, the Ly α/Hβ ratio is also consistent with being the Case B value. The Case B ratios provide strong support for the self-shielded broad-line model of Gaskell, Klimek & Nazarova. It is proposed that the greatly enhanced Ly α/Hβ ratio at very high velocities is a consequence of continuum fluorescence in the Lyman lines (Case C). Reddenings of AGNs mean that the far-UV luminosity is often underestimated by up to an order of magnitude. This is a major factor causing the discrepancies between measured accretion disc sizes and the predictions of simple accretion disc theory. Dust covering fractions for most AGNs are lower than has been estimated. The total mass in lower mass supermassive black holes must be greater than hitherto estimated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Risner, J. M.; Wiarda, D.; Dunn, M. E.
2011-09-30
New coupled neutron-gamma cross-section libraries have been developed for use in light water reactor (LWR) shielding applications, including pressure vessel dosimetry calculations. The libraries, which were generated using Evaluated Nuclear Data File/B Version VII Release 0 (ENDF/B-VII.0), use the same fine-group and broad-group energy structures as the VITAMIN-B6 and BUGLE-96 libraries. The processing methodology used to generate both libraries is based on the methods used to develop VITAMIN-B6 and BUGLE-96 and is consistent with ANSI/ANS 6.1.2. The ENDF data were first processed into the fine-group pseudo-problem-independent VITAMIN-B7 library and then collapsed into the broad-group BUGLE-B7 library. The VITAMIN-B7 library containsmore » data for 391 nuclides. This represents a significant increase compared to the VITAMIN-B6 library, which contained data for 120 nuclides. The BUGLE-B7 library contains data for the same nuclides as BUGLE-96, and maintains the same numeric IDs for those nuclides. The broad-group data includes nuclides which are infinitely dilute and group collapsed using a concrete weighting spectrum, as well as nuclides which are self-shielded and group collapsed using weighting spectra representative of important regions of LWRs. The verification and validation of the new libraries includes a set of critical benchmark experiments, a set of regression tests that are used to evaluate multigroup crosssection libraries in the SCALE code system, and three pressure vessel dosimetry benchmarks. Results of these tests confirm that the new libraries are appropriate for use in LWR shielding analyses and meet the requirements of Regulatory Guide 1.190.« less
NASA Astrophysics Data System (ADS)
Zhou, Wenjuan; Cao, Yuqing; Sui, Dandan; Guan, Weijiang; Lu, Chao; Xie, Jianping
2016-05-01
The prevalence of reactive oxygen species (ROS) production and the enzyme-containing intracellular environment could lead to the fluorescence quenching of bovine serum albumin (BSA)-capped gold nanoclusters (AuNCs). Here we report an efficient strategy to address this issue, where a polymer-like shielding layer is designed to wrap around the Au core to significantly improve the stability of AuNCs against ROS and protease degradation. The key of our design is to covalently incorporate a thiolated AuNC into the BSA-AuNC via carbodiimide-activated coupling, leading to the formation of a AuNC pair inside the cross-linked BSA molecule. The as-designed paired AuNCs in BSA (or BSA-p-AuNCs for short) show improved performances in living cells.The prevalence of reactive oxygen species (ROS) production and the enzyme-containing intracellular environment could lead to the fluorescence quenching of bovine serum albumin (BSA)-capped gold nanoclusters (AuNCs). Here we report an efficient strategy to address this issue, where a polymer-like shielding layer is designed to wrap around the Au core to significantly improve the stability of AuNCs against ROS and protease degradation. The key of our design is to covalently incorporate a thiolated AuNC into the BSA-AuNC via carbodiimide-activated coupling, leading to the formation of a AuNC pair inside the cross-linked BSA molecule. The as-designed paired AuNCs in BSA (or BSA-p-AuNCs for short) show improved performances in living cells. Electronic supplementary information (ESI) available: Detailed experimental materials, apparatus, experimental procedures and characterization data. See DOI: 10.1039/c6nr02178f
Glaciation and regional groundwater flow in the Fennoscandian shield
Provost, A.M.; Voss, C.I.; Neuzil, C.E.
2012-01-01
Regional-scale groundwater flow modeling of the Fennoscandian shield suggests that groundwater flow can be strongly affected by future climate change and glaciation. We considered variable-density groundwater flow in a 1500-km-long and approximately 10-km-deep cross-section through southern Sweden. Groundwater flow and shield brine transport in the cross-sectional model were analyzed under projected surface conditions for the next 140 ka. Simulations suggest that blockage of recharge and discharge by low-permeability permafrost or cold-based ice causes sinking of brine and consequent freshening of near-surface water in areas of natural discharge. Although recharge of basal meltwater is limited by the requirement that water pressure at the base of the ice sheet not exceed the pressure exerted by the weight of the ice, warm-based ice with basal melting creates a potential for groundwater recharge rates much larger than those of present, ice-free conditions. In the simulations, regional-scale redistribution of recharged water by subsurface flow is minor over the duration of a glacial advance (approximately 10 ka). During glacial retreat, significant upward flow of groundwater may occur below the ice sheet owing to pressure release. If the mechanical loading efficiency of the rocks is high, both subsurface penetration of meltwater during glacial advance and up-flow during glacial retreat are reduced because of loading-induced pressure changes. The maximum rate of groundwater discharge in the simulations occurs at the receding ice margin, and some discharge occurs below incursive postglacial seas. Recharge of basal meltwater could decrease the concentration of dissolved solids significantly below present-day levels at depths of up to several kilometers and may bring oxygenated conditions to an otherwise reducing chemical environment for periods exceeding 10 ka.
NASA Technical Reports Server (NTRS)
Mashnik, S. G.; Gudima, K. K.; Sierk, A. J.; Moskalenko, I. V.
2002-01-01
Space radiation shield applications and studies of cosmic ray propagation in the Galaxy require reliable cross sections to calculate spectra of secondary particles and yields of the isotopes produced in nuclear reactions induced both by particles and nuclei at energies from threshold to hundreds of GeV per nucleon. Since the data often exist in a very limited energy range or sometimes not at all, the only way to obtain an estimate of the production cross sections is to use theoretical models and codes. Recently, we have developed improved versions of the Cascade-Exciton Model (CEM) of nuclear reactions: the codes CEM97 and CEM2k for description of particle-nucleus reactions at energies up to about 5 GeV. In addition, we have developed a LANL version of the Quark-Gluon String Model (LAQGSM) to describe reactions induced both by particles and nuclei at energies up to hundreds of GeVhucleon. We have tested and benchmarked the CEM and LAQGSM codes against a large variety of experimental data and have compared their results with predictions by other currently available models and codes. Our benchmarks show that CEM and LAQGSM codes have predictive powers no worse than other currently used codes and describe many reactions better than other codes; therefore both our codes can be used as reliable event-generators for space radiation shield and cosmic ray propagation applications. The CEM2k code is being incorporated into the transport code MCNPX (and several other transport codes), and we plan to incorporate LAQGSM into MCNPX in the near future. Here, we present the current status of the CEM2k and LAQGSM codes, and show results and applications to studies of cosmic ray propagation in the Galaxy.
Geology along the Blue Ridge Parkway in Virginia
Carter, Mark W.; Southworth, C. Scott; Tollo, Richard P.; Merschat, Arthur J.; Wagner, Sara; Lazor, Ava; Aleinikoff, John N.
2017-01-01
Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the boundary of the central and southern Appalachians, rocks along the parkway showcase the transition from the para-autochthonous Blue Ridge anticlinorium of northern and central Virginia to the allochthonous eastern Blue Ridge in southern Virginia. From mile post (MP) 0 near Waynesboro, Virginia, to ~MP 124 at Roanoke, the parkway crosses the unconformable to faulted boundary between Mesoproterozoic basement in the core of the Blue Ridge anticlinorium and Neoproterozoic to Cambrian metasedimentary and metavolcanic cover rocks on the western limb of the structure. Mesoproterozoic basement rocks comprise two groups based on SHRIMP U-Pb zircon geochronology: Group I rocks (1.2-1.14 Ga) are strongly foliated orthogneisses, and Group II rocks (1.08-1.00 Ga) are granitoids that mostly lack obvious Mesoproterozoic deformational features.Neoproterozoic to Cambrian cover rocks on the west limb of the anticlinorium include the Swift Run and Catoctin Formations, and constituent formations of the Chilhowee Group. These rocks unconformably overlie basement, or abut basement along steep reverse faults. Rocks of the Chilhowee Group are juxtaposed against Cambrian rocks of the Valley and Ridge province along southeast- and northwest-dipping, high-angle reverse faults. South of the James River (MP 64), Chilhowee Group and basement rocks occupy the hanging wall of the nearly flat-lying Blue Ridge thrust fault and associated splays.South of the Red Valley high-strain zone (MP 144.5), the parkway crosses into the wholly allochthonous eastern Blue Ridge, comprising metasedimentary and meta-igneous rocks assigned to the Wills Ridge, Ashe, and Alligator Back Formations. These rocks are bound by numerous faults, including the Rock Castle Creek fault that separates Ashe Formation rocks from Alligator Back Formation rocks in the core of the Ararat River synclinorium. The lack of unequivocal paleontologic or geochronologic ages for any of these rock sequences, combined with fundamental and conflicting differences in tectonogenetic models, compound the problem of regional correlation with Blue Ridge cover rocks to the north.The geologic transition from the central to southern Appalachians is also marked by a profound change in landscape and surficial deposits. In central Virginia, the Blue Ridge consists of narrow ridges that are held up by resistant but contrasting basement and cover lithologies. These ridges have shed eroded material from their crests to the base of the mountain fronts in the form of talus slopes, debris flows, and alluvial-colluvial fans for perhaps 10 m.y. South of Roanoke, however, ridges transition into a broad hilly plateau, flanked on the east by the Blue Ridge escarpment and the eastern Continental Divide. Here, deposits of rounded pebbles, cobbles, and boulders preserve remnants of ancestral west-flowing drainage systems.Both bedrock and surficial geologic processes provide an array of economic deposits along the length of the Blue Ridge Parkway corridor in Virginia, including base and precious metals and industrial minerals. However, common stone was the most important commodity for creating the Blue Ridge Parkway, which yielded building stone for overlooks and tunnels, or crushed stone for road base and pavement.
Measurements of the 40Ar(n, γ)41Ar radiative-capture cross section between 0.4 and 14.8 MeV
NASA Astrophysics Data System (ADS)
Bhike, Megha; Fallin, B.; Tornow, W.
2014-09-01
The 40Ar(n, γ)41Ar neutron capture cross section has been measured between 0.4 and 14.8 MeV neutron energy using the activation technique. The data are important for estimating backgrounds in argon-based neutrino and dark-matter detectors and in the neutrino-less double-beta decay search GERDA, which uses liquid argon as cooling and shielding medium. For the first time the 40Ar(n, γ)41Ar cross section has been measured for neutron energies above 1 MeV. Our results are compared to the evaluation ENDF/B-VII.1 and the calculated prediction TENDL-2013. The latter agrees very well with the present results.
NASA Astrophysics Data System (ADS)
Depalo, Rosanna;
2018-01-01
A precise knowledge of the cross section of nuclear fusion reactions is a crucial ingredient in understanding stellar evolution and nucleosynthesis. At stellar temperatures, fusion cross sections are extremely small and difficult to measure. Measuring nuclear cross sections at astrophysical energies is a challenge that triggered a huge amount of experimental work. A breakthrough in this direction was the first operation of an underground accelerator at the Laboratory for Underground Nuclear Astrophysics (LUNA) in Gran Sasso, Italy. The 1400 meters of rocks above the laboratory act as a natural shield against cosmic radiation, suppressing the background by orders of magnitude. The latest results achieved at LUNA are discussed, with special emphasis on the 22Ne(p,γ)23Na reaction. Future perspectives of the LUNA experiment are also illustrated.
Reentrant behaviour in polyvinyl alcohol-borax hydrogels
NASA Astrophysics Data System (ADS)
Lawrence, Mathias B.; Desa, J. A. E.; Aswal, V. K.
2018-01-01
Polyvinyl alcohol (PVA) hydrogels, cross-linked with varying concentrations of borax, were studied with small angle neutron scattering (SANS), x-ray diffraction (XRD) and differential thermal analysis (DTA). The SANS data satisfy the Ornstein-Zernike approximation. The hydrogels are modelled as PVA chains bound by borate cross-links. Water occupies the spaces within the three-dimensional hydrogel network. The mesh size ξ indicates reentrant behaviour i.e. at first, ξ increases and later decreases as a function of borax concentration. The behaviour is explained on the basis of the balance between the charged di-diol cross-links and the shielding by free ions in the solvent. XRD and DTA show the molecular size of water in the solvent and the glass transition temperature commensurate with reentrant behaviour.
Fusion materials high energy-neutron studies. A status report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doran, D.G.; Guinan, M.W.
1980-01-01
The objectives of this paper are (1) to provide background information on the US Magnetic Fusion Reactor Materials Program, (2) to provide a framework for evaluating nuclear data needs associated with high energy neutron irradiations, and (3) to show the current status of relevant high energy neutron studies. Since the last symposium, the greatest strides in cross section development have been taken in those areas providing FMIT design data, e.g., source description, shielding, and activation. In addition, many dosimetry cross sections have been tentatively extrapolated to 40 MeV and integral testing begun. Extensive total helium measurements have been made inmore » a variety of neutron spectra. Additional calculations are needed to assist in determining energy dependent cross sections.« less
Perspective view over the Grand Canyon, Arizona
2001-10-22
This simulated true color perspective view over the Grand Canyon was created from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data acquired on May 12, 2000. The Grand Canyon Village is in the lower foreground; the Bright Angel Trail crosses the Tonto Platform, before dropping down to the Colorado Village and then to the Phantom Ranch (green area across the river). Bright Angel Canyon and the North Rim dominate the view. At the top center of the image the dark blue area with light blue haze is an active forest fire. http://photojournal.jpl.nasa.gov/catalog/PIA01908
Trace element abundances of high-MgO glasses from Kilauea, Mauna Loa and Haleakala volcanoes, Hawaii
Wagner, T.P.; Clague, D.A.; Hauri, E.H.; Grove, T.L.
1998-01-01
We performed an ion-microprobe study of eleven high-MgO (6.7-14.8 wt%) tholeiite glasses from the Hawaiian volcanoes Kilauea, Mauna Loa and Haleakala. We determined the rare earth (RE), high field strength, and other selected trace element abundances of these glasses, and used the data to establish their relationship to typical Hawaiian shield tholeiite and to infer characteristics of their source. The glasses have trace element abundance characteristics generally similar to those of typical shield tholeiites, e.g. L(light)REE/H(heavy)REE(C1) > 1. The Kilauea and Mauna Loa glasses, however, display trace and major element characteristics that cross geochemical discriminants observed between Kilauea and Mauna Loa shield lavas. The glasses contain a blend of these discriminating chemical characteristics, and are not exactly like the typical shield lavas from either volcano. The production of these hybrid magmas likely requires a complexly zoned source, rather than two unique sources. When corrected for olivine fractionation, the glass data show correlations between CaO concentration and incompatible trace element abundances, indicating that CaO may behave incompatibly during melting of the tholeiite source. Furthermore, the tholeiite source must contain residual garnet and clinopyroxene to account for the variation in trace element abundances of the Kilauea glasses. Inversion modeling indicates that the Kilauea source is flat relative to C1 chondrites, and has a higher bulk distribution coefficient for the HREE than the LREE.
Onset of ice VII phase during ps laser pulse propagation through liquid water
NASA Astrophysics Data System (ADS)
Paturi, Prem Kiran; Vaddapally, Rakesh Kumar; Acrhem Team
2015-06-01
Water dominantly present in liquid state on earth gets transformed to crystalline polymorphs under different dynamic loading conditions. Out of 15 different crystalline phases discovered till date, ice VII is observed to be stable over wide pressure (2-63 GPa) and temperature (>273 K) ranges. We present the onset of ice VII phase at low threshold of 2 mJ/pulse during 30 ps (532 nm, 10 Hz) laser pulse induced shock propagating through liquid water. Role of input pulse energy on the evolution of Stoke's and anti-Stoke's Raman shift of the dominant A1g mode of ice VII, filamentation, free-electrons, plasma shielding is presented. The H-bond network rearrangement, electron ion energy transfer time coinciding with the excitation pulse duration supported by the filamentation and plasma shielding of the ps laser pulses reduced the threshold of ice VII structure formation. Filamentation and the plasma shielding have shown the localized creation and sustenance of ice VII structure in liquid water over 3 mm length and 50 μm area of cross-section. The work is supported by Defence Research and Developement Organization, India through Grants-in-Aid Program.
Computation of a Canadian SCWR unit cell with deterministic and Monte Carlo codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harrisson, G.; Marleau, G.
2012-07-01
The Canadian SCWR has the potential to achieve the goals that the generation IV nuclear reactors must meet. As part of the optimization process for this design concept, lattice cell calculations are routinely performed using deterministic codes. In this study, the first step (self-shielding treatment) of the computation scheme developed with the deterministic code DRAGON for the Canadian SCWR has been validated. Some options available in the module responsible for the resonance self-shielding calculation in DRAGON 3.06 and different microscopic cross section libraries based on the ENDF/B-VII.0 evaluated nuclear data file have been tested and compared to a reference calculationmore » performed with the Monte Carlo code SERPENT under the same conditions. Compared to SERPENT, DRAGON underestimates the infinite multiplication factor in all cases. In general, the original Stammler model with the Livolant-Jeanpierre approximations are the most appropriate self-shielding options to use in this case of study. In addition, the 89 groups WIMS-AECL library for slight enriched uranium and the 172 groups WLUP library for a mixture of plutonium and thorium give the most consistent results with those of SERPENT. (authors)« less
Instrumental background in balloon-borne gamma-ray spectrometers and techniques for its reduction
NASA Technical Reports Server (NTRS)
Gehrels, N.
1985-01-01
Instrumental background in balloon-borne gamma-ray spectrometers is presented. The calculations are based on newly available interaction cross sections and new analytic techniques, and are the most detailed and accurate published to date. Results compare well with measurements made in the 20 keV to 10 MeV energy range by the Goddard Low Energy Gamma-ray Spectrometer (LEGS). The principal components of the continuum background in spectrometers with GE detectors and thick active shields are: (1) elastic neutron scattering of atmospheric neutrons on the Ge nuclei; (2) aperture flux of atmospheric and cosmic gamma rays; (3) beta decays of unstable nuclides produced by nuclear interactions of atmospheric protons and neutrons with Ge nuclei; and (4) shield leakage of atmospheric gamma rays. The improved understanding of these components leads to several recommended techniques for reducing the background.
De Boisblanc, D.R.; Thomas, M.E.; Jones, R.M.; Hanson, G.H.
1958-10-21
Heterogeneous reactors of the type which is both cooled and moderated by the same fluid, preferably water, and employs highly enriched fuel are reported. In this design, an inner pressure vessel is located within a main outer pressure vessel. The reactor core and its surrounding reflector are disposed in the inner pressure vessel which in turn is surrounded by a thermal shield, Coolant fluid enters the main pressure vessel, fiows downward into the inner vessel where it passes through the core containing tbe fissionable fuel assemblies and control rods, through the reflector, thence out through the bottom of the inner vessel and up past the thermal shield to the discharge port in the main vessel. The fuel assemblles are arranged in the core in the form of a cross having an opening extending therethrough to serve as a high fast flux test facility.
Photoinduced collagen cross-linking: a new approach to venous insufficiency.
Frullini, Alessandro; Manetti, Leonardo; Di Cicco, Emiliano; Fortuna, Damiano
2011-08-01
What little research has been done on methods of venous valve function recovery with radiofrequency has had disappointing results. Valvuloplasty has some supporters, but the majority of physicians do not consider it a valid therapeutic option. To test a new method of treating varicose veins based on their collagen structure. This procedure it is not a thermal treatment, but it is fast, with significant shrinking and preservation of the endothelium. In the laboratory, we subjected greater saphenous vein specimens to irradiation with a blue light-emitting diode generated (wavelength 450-480 nm) while a riboflavin solution (vitamin B2) was administered. The riboflavin acts as a cross-linking agent, and the blue light as the activator. In this photo-induced reaction, oxygen singlet is produced with oxidative deamination, forming new covalent bonds between collagen fibrils and water. In venous specimens, we demonstrated fast and significant shrinkaged without histologic evidence of endothelial damage and with evident change in mechanical properties of varicose veins. Photochemically induced collagen cross-linking to restructure varicose veins is only a research field but may become an important tool for recovery of vein diameter and valve function. © 2011 by the American Society for Dermatologic Surgery, Inc.
VizieR Online Data Catalog: Census of blue stars in SDSS DR8 (Scibelli+, 2014)
NASA Astrophysics Data System (ADS)
Scibelli, S.; Newberg, H. J.; Carlin, J. L.; Yanny, B.
2015-02-01
We present a census of the 12060 spectra of blue objects ((g-r)0<-0.25) in the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). As part of the data release, all of the spectra were cross-correlated with 48 template spectra of stars, galaxies, and QSOs to determine the best match. We compared the blue spectra by eye to the templates assigned in SDSS DR8. 10856 of the objects matched their assigned template, 170 could not be classified due to low signal-to-noise ratio, and 1034 were given new classifications. We identify 7458 DA white dwarfs, 1145 DB white dwarfs, 273 rarer white dwarfs (including carbon, DZ, DQ, and magnetic), 294 subdwarf O stars, 648 subdwarf B stars, 679 blue horizontal branch stars, 1026 blue stragglers, 13 cataclysmic variables, 129 white dwarf-M dwarf binaries, 36 objects with spectra similar to DO white dwarfs, 179, quasi-stellar objects (QSOs), and 10 galaxies. We provide two tables of these objects, sample spectra that match the templates, figures showing all of the spectra that were grouped by eye, and diagnostic plots that show the positions, colors, apparent magnitudes, proper motions, etc., for each classification. (3 data files).
Suebsing, R; Pradeep, P J; Jitrakorn, S; Sirithammajak, S; Kampeera, J; Turner, W A; Saksmerprome, V; Withyachumnarnkul, B; Kiatpathomchai, W
2016-07-01
Infectious spleen and kidney necrosis virus (ISKNV) has recently been recognized as a causative agent of serious systemic disease in tilapia. Our objective was to establish a new colorimetric loop-mediated isothermal amplification (LAMP) assay with pre-addition of hydroxynapthol blue (blue-LAMP) to investigate ISKNV transmission in tilapia. The blue-LAMP, targeting a major capsid protein gene of ISKNV, was conducted at 65°C for 45 min, allowing unaided visual detection of the pathogen based on colour change without cross-amplification of other known fish pathogens tested. Comparison of blue-LAMP and PCR assays revealed a higher detection level for blue-LAMP assay (41·33%) in a population of farmed tilapia infected with ISKNV. The investigation of ISKNV transmission pattern in farmed red tilapia using the blue-LAMP revealed a possible matroclinical form. The presence of ISKNV in the gonad samples was confirmed by in situ LAMP assay. Positive signals only appeared in ovarian follicles, and not in oocytes. Moreover, tissue tropism assay revealed that the brain was the main target organ in both farmed red tilapia (40%) and Nile tilapia (20%). The developed blue-LAMP assay has the potential to be used as a viable tool for screening covert and natural infections of ISKNV in tilapia. The evidence of vertical transmission of ISKNV infection in tilapia indicates the seriousness of this disease and will require a close attention and collaboration between tilapia hatcheries and disease experts in order to find a solution. The new blue-LAMP assay is a time-saving and economically viable detection tool, which allows unaided visual detection for ISKNV in tilapia, and it could be applicable for field applications. Evidence on the vertical transmission of ISKNV in farmed tilapia suggests a need for developing farm management practices to control the spread of virus in aquaculture industries. © 2016 The Society for Applied Microbiology.
Wei, Shufang; Zhang, Cuiying; Zhang, Shaoru; Xu, Yanyun; Mu, Guoying
2017-10-01
To study the treatment effect of corneal collagen cross-linking (CXL) combined with 440 nm blue light and riboflavin on bacterial corneal ulcer using animal experiments. A total of 21 New Zealand white rabbits that developed Staphylococcus aureus corneal ulcer were randomly divided into three groups. Seven rabbits were used as blank control groups; seven rabbits were treated with CXL combined with riboflavin and 440 nm blue light; and seven rabbits were treated with CXL combined with riboflavin and 370 nm ultraviolet A light. Necrotic tissues or secretions from the ulcer surface, eye secretions, conjunctival hyperemia, hypopyon, corneal infiltration, and pathological changes of the cornea were all observed. The 1st, 3th, and 7th day after CXL treatment, a statistically significant difference was found among the inflammation scores of the three groups. The scores of 440 and 370 groups decreased gradually, significantly lower than that of the control group. Bacterial cultures of 440 and 370 groups turned to be negative while that of the control group remained positive. After 1 day of CXL treatment, pathology pictures of the three groups all showed loss of corneal epithelia with many inflammatory cells in deep stroma. After 7 days of CXL treatment, abscess formed in almost all corneal area in the control group, while in 440 and 370 groups, multilayer healing of corneal epithelia, neovascularization, and many inflammatory cells within ulcers and proliferation of a small amount of fibroblast were seen. CXL combined with riboflavin and 440 nm blue light is effective in treating S. aureus corneal ulcer.
GALAXY GROWTH BY MERGING IN THE NEARBY UNIVERSE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang Tao; Hogg, David W.; Blanton, Michael R., E-mail: david.hogg@nyu.edu
2012-11-10
We measure the mass growth rate by merging for a wide range of galaxy types. We present the small-scale (0.014 h {sup -1} {sub 70} Mpc < r < 11 h {sub 70} {sup -1} Mpc) projected cross-correlation functions w(r {sub p}) of galaxy subsamples from the spectroscopic sample of the NYU Value-Added Galaxy Catalog (5 Multiplication-Sign 10{sup 5} galaxies of redshifts 0.03 < z < 0.15) with galaxy subsamples from the Sloan Digital Sky Survey imaging (4 Multiplication-Sign 10{sup 7} galaxies). We use smooth fits to de-project the two-dimensional functions w(r {sub p}) to obtain smooth three-dimensional real-space cross-correlationmore » functions {xi}(r) for each of several spectroscopic subsamples with each of several imaging subsamples. Because close pairs are expected to merge, the three-space functions and dynamical evolution time estimates provide galaxy accretion rates. We find that the accretion onto massive blue galaxies and onto red galaxies is dominated by red companions, and that onto small-mass blue galaxies, red and blue galaxies make comparable contributions. We integrate over all types of companions and find that at fixed stellar mass, the total fractional accretion rates onto red galaxies ({approx}3 h {sub 70} percent per Gyr) are greater than that onto blue galaxies ({approx}1 h {sub 70} percent per Gyr). These rates are almost certainly overestimates because we have assumed that all close pairs merge as quickly as the merger time that we used. One conclusion of this work is that if the total growth of red galaxies from z = 1 to z = 0 is mainly due to merging, the merger rates must have been higher in the past.« less
Comparison of red autofluorescing plaque and disclosed plaque-a cross-sectional study.
Volgenant, Catherine M C; Fernandez Y Mostajo, Mercedes; Rosema, Nanning A M; van der Weijden, Fridus A; Ten Cate, Jacob M; van der Veen, Monique H
2016-12-01
The aim of this cross-sectional study was to assess the correlation between dental plaque scores determined by the measurement of red autofluorescence or by visualization with a two-tone solution. Clinical photographs were used for this study. Overnight plaque from the anterior teeth of 48 participants was assessed for red fluorescence on photographs (taken with a QLF-camera) using a modified Quigley & Hein (mQH) index. A two-tone disclosing solution was applied. Total disclosed plaque was clinically assessed using the mQH index. In addition, total and blue disclosed plaque was scored on clinical photographs using the mQH index. A strong correlation was observed between the total disclosed plaque scored on photographs and the clinical scores (r = 0.70 at site level; r = 0.88 at subject level). The correlation between red fluorescent plaque and total plaque, as assessed on the photographs, was moderate to strong and significant (r = 0.50 at the site level; r = 0.70 at the subject level), with the total plaque scores consistently higher than the red fluorescent plaque scores. The correlation between red fluorescent plaque and blue disclosed plaque was weak to moderate and significant (r = 0.30 at the site level; r = 0.50 at the subject level). Plaque, as scored on white-light photographs, corresponds well with clinically assessed plaque. A weak to moderate correlation between red fluorescing plaque and total disclosed plaque or blue disclosed plaque was found. What at present is considered to be matured dental plaque, which appears blue following the application of a two-tone disclosing solution, is not in agreement with red fluorescent dental plaque assessment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chavez, III, Ramiro; Cai, Min; Tlach, Brian
Four new cross-conjugated small molecules based on a central benzo[1,2-d:4,5-d']bisoxazole moiety possessing semi-independently tunable HOMO and LUMO levels were synthesized and the properties of these materials were evaluated experimentally and theoretically. The molecules were thermally stable with 5% weight loss occurring well above 350 °C. The cruciforms all exhibited blue emission in solution ranging from 433–450 nm. Host–guest OLEDs fabricated from various concentrations of these materials using the small molecule host 4,4'-bis(9-carbazolyl)-biphenyl (CBP) exhibited deep blue-emission with Commission Internationale de L'Eclairage (CIE) coordinates of (0.15 ≤ x ≤ 0.17, 0.05 ≤ y ≤ 0.11), and maximum luminance efficiencies as highmore » as ~2 cd A–1. Lastly, these results demonstrate the potential of benzobisoxazole cruciforms as emitters for developing high-performance deep blue OLEDs.« less
Cement line staining in undecalcified thin sections of cortical bone
NASA Technical Reports Server (NTRS)
Bain, S. D.; Impeduglia, T. M.; Rubin, C. T.
1990-01-01
A technique for demonstrating cement lines in thin, undecalcified, transverse sections of cortical bone has been developed. Cortical bone samples are processed and embedded undecalcified in methyl methacrylate plastic. After sectioning at 3-5 microns, cross-sections are transferred to a glass slide and flattened for 10 min. Sections of cortical bone are stained for 20 sec free-floating in a fresh solution of 1% toluidine blue dissolved in 0.1% formic acid. The section is dehydrated in t-butyl alcohol, cleared in xylene, and mounted with Eukitt's medium. Reversal lines appear as thin, scalloped, dark blue lines against a light blue matrix, whereas bone formation arrest lines are thicker with a smooth contour. With this technique cellular detail, osteoid differentiation, and fluorochrome labels are retained. Results demonstrate the applicability of a one-step staining method for cement lines which will facilitate the assessment of bone remodeling activity in thin sections of undecalcified cortical bone.
CloudSat First Image of a Warm Front Storm Over the Norwegian Sea
NASA Technical Reports Server (NTRS)
2006-01-01
[figure removed for brevity, see original site] Figure 1 CloudSat's first image, of a warm front storm over the Norwegian Sea, was obtained on May 20, 2006. In this horizontal cross-section of clouds, warm air is seen rising over colder air as the satellite travels from right to left. The red colors are indicative of highly reflective particles such as water droplets (or rain) or larger ice crystals (or snow), while the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudSat Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The blue line below the Cloud Profiling Radar image indicates that the data were taken over water. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) infrared image taken at nearly the same time.CloudSat Image of a Polar Night Storm Near Antarctica
NASA Technical Reports Server (NTRS)
2006-01-01
[figure removed for brevity, see original site] Figure 1 CloudSat image of a horizontal cross-section of a polar night storm near Antarctica. Until now, clouds have been hard to observe in polar regions using remote sensing, particularly during the polar winter or night season. The red colors are indicative of highly reflective particles such as water (rain) or ice crystals, while the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudSat Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The blue line below the Cloud Profiling Radar image indicates that the data were taken over water; the brown line below the image indicates the relative elevation of the land surface. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) infrared image taken at nearly the same time.Stuart, Elizabeth A.; Barry, Colleen L.; Donohue, Julie M.; Greenfield, Shelly F.; Duckworth, Kenneth; Song, Zirui; Kouri, Elena M.; Ebnesajjad, Cyrus; Mechanic, Robert; Chernew, Michael E.; Huskamp, Haiden A.
2016-01-01
Background and Aims Global payment and accountable care reform efforts in the US may connect more individuals with substance use disorders (SUD) to treatment. We tested whether such changes instituted under an ‘Alternative Quality Contract’ (AQC) model within the Blue Cross Blue Shield of Massachusetts’ (BCBSMA) insurer increased care for individuals with SUD. Design Difference-in-differences design comparing enrollees in AQC organizations with a comparison group of enrollees in organizations not participating in the AQC. Setting Massachusetts, USA. Participants BCBSMA enrollees aged 13–64 from 2006–2011 (three years prior to and after implementation) representing 1,333,534 enrollees and 42,801 SUD service users. Measurements Outcomes were SUD service use and spending and SUD performance metrics. Primary exposures were enrollment in an AQC provider organization and whether the AQC organization did or did not face risk for behavioral health costs. Findings Enrollees in AQC organizations facing behavioral health risk experienced no change in the probability of using SUD services (1.64% vs. 1.66%; p=0.63), SUD spending ($2,807 vs. $2,700; p=0.34) or total spending ($12,631 vs. $12,849; p=0.53), or SUD performance metrics (identification: 1.73% vs. 1.76%, p=0.57; initiation: 27.86% vs. 27.02%, p=0.50; engagement: 11.19% vs. 10.97%, p=0.79). Enrollees in AQC organizations not at risk for behavioral health spending experienced a small increase in the probability of using SUD services (1.83% vs. 1.66%; p=0.003) and the identification performance metric (1.92% vs. 1.76%; p=0.007), and a reduction in SUD medication use (11.84% vs. 14.03%; p=0.03) and the initiation performance metric (23.76% vs. 27.02%; p=0.005). Conclusions A global payment and accountable care model introduced in Massachusetts USA (in which a health insurer provided care providers with fixed prepayments to cover most or all of their patients’ care during a specified time period, incentivizing providers to keep their patients’ healthy and reduce costs) did not lead to sizable changes in substance use disorder service use during the first three years following its implementation. PMID:27517740
Stuart, Elizabeth A; Barry, Colleen L; Donohue, Julie M; Greenfield, Shelly F; Duckworth, Kenneth; Song, Zirui; Mechanic, Robert; Kouri, Elena M; Ebnesajjad, Cyrus; Chernew, Michael E; Huskamp, Haiden A
2017-01-01
Global payment and accountable care reform efforts in the United States may connect more individuals with substance use disorders (SUD) to treatment. We tested whether such changes instituted under an Alternative Quality Contract (AQC) model within the Blue Cross Blue Shield of Massachusetts' (BCBSMA) insurer increased care for individuals with SUD. Difference-in-differences design comparing enrollees in AQC organizations with a comparison group of enrollees in organizations not participating in the AQC. Massachusetts, USA. BCBSMA enrollees aged 13-64 years from 2006 to 2011 (3 years prior to and after implementation) representing 1 333 534 enrollees and 42 801 SUD service users. Outcomes were SUD service use and spending and SUD performance metrics. Primary exposures were enrollment into an AQC provider organization and whether the AQC organization did or did not face risk for behavioral health costs. Enrollees in AQC organizations facing behavioral health risk experienced no change in the probability of using SUD services (1.64 versus 1.66%; P = 0.63), SUD spending ($2807 versus $2700; P = 0.34) or total spending ($12 631 versus $12 849; P = 0.53), or SUD performance metrics (identification: 1.73 versus 1.76%, P = 0.57; initiation: 27.86 versus 27.02%, P = 0.50; engagement: 11.19 versus 10.97%, P = 0.79). Enrollees in AQC organizations not at risk for behavioral health spending experienced a small increase in the probability of using SUD services (1.83 versus 1.66%; P = 0.003) and the identification performance metric (1.92 versus 1.76%; P = 0.007) and a reduction in SUD medication use (11.84 versus 14.03%; P = 0.03) and the initiation performance metric (23.76 versus 27.02%; P = 0.005). A global payment and accountable care model introduced in Massachusetts, USA (in which a health insurer provided care providers with fixed prepayments to cover most or all of their patients' care during a specified time-period, incentivizing providers to keep their patients healthy and reduce costs) did not lead to sizable changes in substance use disorder service use during the first 3 years following its implementation. © 2016 Society for the Study of Addiction.
Payment of hospital cardiac services.
Unger, W J
1991-01-01
This report describes how acute-care community hospitals in the United States get paid for services when their patients either are entitled to Medicare or Medicaid benefits or subscribe to a Blue Cross or Blue Shield plan, a commercial insurance plan, a health maintenance organization, a preferred provider organization, or some other third-party payment mechanism. The focus of this report is on cardiac services, which are the most common type of inpatient services provided by acute-care community hospitals. Over the past three decades, extraordinary advances in medical and surgical technologies as well as healthier life-styles have cut the annual death rate for coronary heart disease in half. Despite this progress, cardiovascular disease remains the number one cause of hospitalization. On average nationwide, diseases and disorders of the circulatory system are the primary reason for 17 percent of all patient admissions, and among the nation's 35 million Medicare beneficiaries they are the primary reason for 25 percent of all admissions. In the United States heart disease is the leading cause of death and a major cause of morbidity. Its diagnosis and treatment are often complex and costly, often requiring multiple hospitalizations and years of medical management. To focus management attention and resources on the immense cardiology marketplace, many hospitals have hired individuals with strong clinical backgrounds to manage their cardiology programs. These "front-line" managers play a key role in coordinating a hospital's services for patients with cardiovascular disease. Increasingly, these managers are being asked to become active participants in the reimbursement process. This report was designed to meet their needs. Because this report describes common reimbursement principles and practices applicable to all areas of hospital management and because it provides a "tool kit" of analytical, planning, and forecasting techniques, it could also be useful to hospital marketing, planning, finance, and accounting personnel. In addition, the rich reservoir of data contained in the appendixes to this report may be of interest to hospital chief executive officers, cardiologists, and cardiovascular surgeons. In addition to the introduction and summary sections, this report contains five main sections. Sequentially, these deal with: the ways hospitals get paid for what they do; ICD-9 coding DRGs, PPS, and Medicare claims administration; ways to analyze how well your hospital is doing; planning and forecasting; the new Resource-Based Relative Value Scale.(ABSTRACT TRUNCATED AT 400 WORDS)
Development of an ion-pair to improve the colon permeability of a low permeability drug: Atenolol.
Lozoya-Agullo, Isabel; González-Álvarez, Isabel; González-Álvarez, Marta; Merino-Sanjuán, Matilde; Bermejo, Marival
2016-10-10
To ensure the optimal performance of oral controlled release formulations, drug colon permeability is one of the critical parameters. Consequently developing this kind of formulations for low permeability molecules requires strategies to increase their ability to cross the colonic membrane. The objective of this work is to show if an ion-pair formation can improve the colon permeability of atenolol as a low permeability drug model. Two counter ions have been tested: brilliant blue and bromophenol blue. The Distribution coefficients at pH7.00 (DpH7) of atenolol, atenolol + brilliant blue and atenolol + bromophenol blue were experimentally determined in n-octanol. Moreover, the colonic permeability was determined in rat colon using in situ closed loop perfusion method based in Doluisio's Technique. To check the potential effects of the counter ions on the membrane integrity, a histological assessment of colonic tissue was done. The results of the partitioning studies were inconclusive about ion-pair formation; nevertheless colon permeability was significantly increased by both counter ions (from 0.232±0.021cm/s to 0.508±0.038cm/s in the presence of brilliant blue and to 0.405±0.044cm/s in the presence of bromophenol blue). Neither damage on the membrane was observed on the histological studies, nor any change on paracellular permeability suggesting that the permeability enhancement could be attributed to the ion-pair formation. Copyright © 2016 Elsevier B.V. All rights reserved.
Sun, Huaiyan; Jin, Xinyu; Long, Nengbing; Zhang, Ruifeng
2017-02-01
A ZnO nanowires/macroporous SiO 2 composite was used as support to immobilize horseradish peroxidase (HRP) by in-situ cross-linking method. Using diethylene glycol diglycidyl ether (DDE) as a long-chained cross-linker, it was adsorbed on the surface of ZnO nanowires before reaction with HRPs, the resulted composite was quite different from the traditional cross-linking enzyme aggregates (CLEAs) on both structure and catalytic performance. The immobilized HRP showed high activity in the decolorization of azo dyes. The effect of various conditions such as the loading amount of HRP, solution pH, temperature, contact time and concentration of dye were optimized on the decolorization. The decolorization percentage of Acid Blue 113 and Acid black 10 BX reached as high as 95.4% and 90.3%, respectively. The immobilized HRP gave the highest decolorization rate under dye concentration as 50mg/L and reaction time of 35min. The immobilized HRP exhibited much better resistance to temperature and pH inactivation than free HRP. The storage stability and reusability were greatly improved through the immobilization, from the decolorization of Acid blue 113 it was found that 80.4% of initial efficiency retained after incubation at 4°C for 60 days, and that 79.4% of decolorization efficiency retained after 12 cycles reuse. Copyright © 2016 Elsevier B.V. All rights reserved.
Visualization of Capsule Reentry Vehicle Heat Shield Ablation Using Naphthalene PLIF
NASA Technical Reports Server (NTRS)
Combs, Christopher S.; Clemens, Noel T.; Danehy, Paul M.
2014-01-01
The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield and improved understanding of the ablation process would be beneficial for design purposes. Given that ablation is a multi-physics process involving heat and mass transfer, codes aiming to predict heat shield ablation are in need of experimental data pertaining to the turbulent transport of ablation products for validation. At The University of Texas at Austin, a technique is being developed that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to visualize the transport of ablation products in a supersonic flow. Since ablation at reentry temperatures can be difficult to recreate in a laboratory setting it is desirable to create a limited physics problem and simulate the ablation process at relatively low temperature conditions using naphthalene. A scaled Orion MPCV model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel at various angles of attack in the current work. PLIF imaging reveals the distribution of the ablation products as they are transported into the heat-shield boundary layer and over the capsule shoulders into the separated shear layer and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. High concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure were observed using the naphthalene PLIF technique. The capsule shear layer was also shown to generally appear to be more turbulent at lower angles of attack. Furthermore, the PLIF signal increased steadily over the course of a run indicating that during a wind tunnel run the model heated up and the rate of naphthalene ablation increased. The shear layer showed increasing signs of turbulence over the course of a wind tunnel run as well, likely because of the combination of increased surface roughness and surface blowing rate. PLIF imaging also detected regions with a relatively low concentration of naphthalene in the capsule backshell recirculation region that are most likely the result of cross-flow-induced vortices on the capsule afterbody.
Jupiter: Cosmic Jekyll and Hyde.
Grazier, Kevin R
2016-01-01
It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to shield or intercept Earth-bound comets originating in the outer Solar System is poor, and that the importance of jovian planets on the formation of life is not that they act as shields, but rather that they deliver life-enabling volatiles to the terrestrial planets.
NASA Astrophysics Data System (ADS)
Neuhäuser, D. L.; Neuhäuser, R.
2015-12-01
The interpretation of the strong 14C variation around AD 775 as one (or several) solar super-flare(s) by, e.g., Usoskin et al. (2013) is based on alleged aurora sightings in the mid AD 770s in Europe: A red cross/crucifix in AD 773/4/6 from the Anglo-Saxon Chronicle, inflamed shields in AD 776 (both listed in the aurora catalogue of Link 1962), and riders on white horses in AD 773 (newly proposed as aurora in Usoskin et al. 2013), the two latter from the Royal Frankish Annals. We discuss the reports about these three sightings in detail here. We can show that all three can be interpreted convincingly as halo displays: The red cross or crucifix is formed by the horizontal arc and a vertical pillar of light (either with the Sun during sunset or with the moon after sunset); the inflamed shields and the riders on white horses were both two mock suns, especially the latter narrated in form of a Christian adaptation of the antique dioscuri motive. While the latter event took place early in AD 774 (dated AD 773 in Usoskin et al. 2013), the two other sightings have to be dated AD 776, i.e. anyway too late for being in connection with a 14C rise that started before AD 775. We also sketch the ideological background of those sightings and there were many similar reports throughout that time. In addition, we present a small drawing of a lunar halo display with horizontal arc and vertical pillar forming a cross for shortly later, namely AD 806 June 4, the night of full moon, also from the Anglo-Saxon Chronicle; we also show historic observations of halo phenomena (mock suns and crosses) from G. Kirch and Hevelius - and a modern photograph.
New Neutron Cross-Section Measurements at ORELA for Improved Nuclear Data Calculations
NASA Astrophysics Data System (ADS)
Guber, K. H.; Leal, L. C.; Sayer, R. O.; Koehler, P. E.; Valentine, T. E.; Derrien, H.; Harvey, J. A.
2005-05-01
Many older neutron cross-section evaluations from libraries such as ENDF/B-VI or JENDL-3.2 exhibit deficiencies or do not cover energy ranges that are important for criticality safety applications. These deficiencies may occur in the resolved and unresolved-resonance regions. Consequently, these evaluated data may not be adequate for nuclear criticality calculations where effects such as self-shielding, multiple scattering, or Doppler broadening are important. To support the Nuclear Criticality Predictability Program, neutron cross-section measurements have been initiated at the Oak Ridge Electron Linear Accelerator (ORELA). ORELA is the only high-power white neutron source with excellent time resolution still operating in the United States. It is ideally suited to measure fission, neutron total, and capture cross sections in the energy range from 1 eV to ˜600 keV, which is important for many nuclear criticality safety applications.
Imai, Shinsuke; Akita, Kaori; Tomotake, Muneaki; Sawada, Hiroshi
2006-02-08
By using a model reaction system representing blue-green discoloration that occurs when purees of onion (Allium cepa L.) and garlic (Allium sativum L.) are mixed, we isolated two pigment precursors (PPs) and a reddish-purple pigment (PUR-1) and determined their chemical structures. PPs were isolated from a heat-treated solution containing color developer (CD) and either l-valine or l-alanine, and their structures were determined as 2-(3,4-dimethylpyrrolyl)-3-methylbutanoic acid (PP-Val), and 2-(3,4-dimethyl-1H-pyrrolyl) propanoic acid (PP-Ala), respectively. Next, PUR-1 was isolated from a heat-treated solution containing PP-Val and allicin, and its structure was determined as (1E)-1-(1-((1S)-1-carboxy-2-methylpropyl)-3,4-dimethyl-1H-pyrrol-2-yl)-prop-1-enylene-3-(1-((1S)-1-carboxy-2-methylpropyl)-3,4-dimethyl-1H-pyrrol-2-ylidenium). The structure of PUR-1 suggested that PP molecules containing a 3,4-dimethyl pyrrole ring had been cross-linked by an allyl group of allicin to form conjugated pigments. While PUR-1 is a dipyrrole compound exhibiting a reddish-purple color, a color shift toward blue to green can be expected as the cross-linking reaction continues to form, for example, tri- or tetrapyrrole compounds.
NASA Technical Reports Server (NTRS)
2006-01-01
Six hundred and fifty light-years away in the constellation Aquarius, a dead star about the size of Earth, is refusing to fade away peacefully. In death, it is spewing out massive amounts of hot gas and intense ultraviolet radiation, creating a spectacular object called a 'planetary nebula.' In this false-color image, NASA's Hubble and Spitzer Space Telescopes have teamed up to capture the complex structure of the object, called the Helix nebula, in unprecedented detail. The composite picture is made up of visible data from Hubble and infrared data from Spitzer. The dead star, called a white dwarf, can be seen at the center of the image as a white dot. All of the colorful gaseous material seen in the image was once part of the central star, but was lost in the death throes of the star on its way to becoming a white dwarf. The intense ultraviolet radiation being released by the white dwarf is heating and destabilizing the molecules in its surrounding environment, starting from the inside out. Like an electric stovetop slowly heating up from the center first, the hottest and most unstable gas molecules can be seen at the center of the nebula as wisps of blue. The transition to more stable and cooler molecules is clearly depicted as the color of the gas changes from very hot (blue) to hot (yellow) and warm (red). A striking feature of the Helix, first revealed by ground-based images, is its collection of thousands of filamentary structures, or strands of gas. In this image the filaments can be seen under the transparent blue gas as red lines radiating out from the center. Astronomers believe that the molecules in these filaments are able to stay cooler and more stable because dense clumps of materials are shielding them from ultraviolet radiation. This image is a composite showing ionized H-alpha (green) and O III (blue) gases from the Hubble Space Telescope, and molecular hydrogen (red) from Spitzer observations at 4.5 and 8.0 microns.Mallakpour, Shadpour; Shamsaddinimotlagh, Sima
2018-03-01
In the present project in order to prevent agglomeration and better dispersion of TiO 2 nanoparticles (NPs) in the poly(vinyl chloride) (PVC) matrix, initially, the surface of TiO 2 NPs was covered by bovine serum albumin protein (BSA) via sonication method. Then, the TiO 2 -BSA powders were embedded into the PVC matrix using ultrasonic irradiations. With mechanical and magnetic stirring homogenous mixture was not obtained. So sonication process was very essential and vital. Physical, chemical and structural properties of the samples were investigated with various tools. Morphology studies showed the well distribution of spherical TiO 2 NPs in the PVC matrix. TGA analysis showed that nanocomposites (NCs) have higher thermal stability than the pristine polymer. The photocatalytic activity tests by destroying the methylene blue dye on the pristine TiO 2 NPs, TiO 2 -BSA NPs and PVC/TiO 2 -BSA NC 6 wt% were examined. The results showed that the photocatalytic activity of TiO 2 NPs was reduced in the presence of BSA and PVC. It can be concluded that the TiO 2 -BSA NPs and PVC/TiO 2 -BSA NC 6 wt% have UV shielding properties and can protect film from degradation by UV. Copyright © 2017 Elsevier B.V. All rights reserved.
Spatial Distribution and Kinematics of the Molecular Material Associated with eta Carinae
NASA Astrophysics Data System (ADS)
Loinard, Laurent; Kamiński, Tomasz; Serra, Paolo; Menten, Karl M.; Zapata, Luis A.; Rodríguez, Luis F.
2016-12-01
Single-dish submillimeter observations have recently revealed the existence of a substantial, chemically peculiar molecular gas component located in the innermost circumstellar environment of the very massive luminous blue variable star, η Carinae. Here, we present 5″-resolution interferometric observations of the 1\\to 0 rotational transition of hydrogen cyanide (HCN) toward this star obtained with the Australia Telescope Compact Array. The emission is concentrated in the central few arcseconds around η Carinae and shows a clear 150 km s-1 velocity gradient running from west-north-west (blue) to east-south-east (red). Given the extent, location, and kinematics of this molecular material, we associate it with the complex of dusty arcs and knots seen in mid-infrared emission near the center of the Homunculus nebula. Indeed, the shielding provided by this dust could help explain how molecules survive in the presence of the intense UV radiation field produced by η Carinae. The dust located in the central few arcseconds around η Carinae and the molecular component described here most likely formed in situ and out of material expelled by the massive interacting binary system. Thus, η Carinae offers us a rare glimpse of the processes that lead to the formation of dust and molecules around massive stars, which are relevant to the interpretation of dust and molecule detections at high redshifts.
Demonstration of Hybrid Multilayer Insulation for Fixed Thickness Applications
NASA Technical Reports Server (NTRS)
Johnson, Wesley; Fesmire, James; Heckle, Wayne
2015-01-01
Once on orbit, high performing insulation systems for cryogenic systems need just as good radiation (optical) properties as conduction properties. This requires the use of radiation shields with low conductivity spacers in between. By varying the height and cross-sectional area of the spacers between the radiation shields, the relative radiation and conduction heat transfers can be manipulated. However, in most systems, there is a fixed thickness or volume allocated to the insulation. In order to understand how various combinations of different multilayer insulation (MLI) systems work together and further validate thermal models of such a hybrid MLI set up, test data is needed. The MLI systems include combinations of Load Bearing MLI (LB-MLI) and traditional MLI. To further simulate the space launch vehicle case wherein both ambient pressure and vacuum environments are addressed, different cold-side thermal insulation substrates were included for select tests.
Finite temperature static charge screening in quantum plasmas
NASA Astrophysics Data System (ADS)
Eliasson, B.; Akbari-Moghanjoughi, M.
2016-07-01
The shielding potential around a test charge is calculated, using the linearized quantum hydrodynamic formulation with the statistical pressure and Bohm potential derived from finite temperature kinetic theory, and the temperature effects on the force between ions is assessed. The derived screening potential covers the full range of electron degeneracy in the equation of state of the plasma electrons. An attractive force between shielded ions in an arbitrary degenerate plasma exists below a critical temperature and density. The effect of the temperature on the screening potential profile qualitatively describes the ion-ion bound interaction strength and length variations. This may be used to investigate physical properties of plasmas and in molecular-dynamics simulations of fermion plasma. It is further shown that the Bohm potential including the kinetic corrections has a profound effect on the Thomson scattering cross section in quantum plasmas with arbitrary degeneracy.
An Improved Neutron Transport Algorithm for HZETRN
NASA Technical Reports Server (NTRS)
Slaba, Tony C.; Blattnig, Steve R.; Clowdsley, Martha S.; Walker, Steven A.; Badavi, Francis F.
2010-01-01
Long term human presence in space requires the inclusion of radiation constraints in mission planning and the design of shielding materials, structures, and vehicles. In this paper, the numerical error associated with energy discretization in HZETRN is addressed. An inadequate numerical integration scheme in the transport algorithm is shown to produce large errors in the low energy portion of the neutron and light ion fluence spectra. It is further shown that the errors result from the narrow energy domain of the neutron elastic cross section spectral distributions, and that an extremely fine energy grid is required to resolve the problem under the current formulation. Two numerical methods are developed to provide adequate resolution in the energy domain and more accurately resolve the neutron elastic interactions. Convergence testing is completed by running the code for various environments and shielding materials with various energy grids to ensure stability of the newly implemented method.
JENDL-4.0/HE Benchmark Test with Concrete and Iron Shielding Experiments at JAEA/TIARA
NASA Astrophysics Data System (ADS)
Konno, Chikara; Matsuda, Norihiro; Kwon, Saerom; Ohta, Masayuki; Sato, Satoshi
2017-09-01
As a benchmark test of JENDL-4.0/HE released in 2015, we have analyzed the concrete and iron shielding experiments with the quasi mono-energetic 40 and 65 MeV neutron sources at TIARA in JAEA by using MCNP5 and ACE files processed from JENDL-4.0/HE with NJOY2012. As a result, it was found out that the calculation results with JENDL-4.0/HE agreed with the measured ones in the concrete experiment well, while they underestimated the measured ones in the iron experiment with 65 MeV neutrons more for the thicker assemblies. We examined the 56Fe data of JENDL-4.0/HE in detail and it was considered that the larger non-elastic scattering cross sections of 56Fe caused the underestimation in the calculation with JENDL-4.0/HE for the iron experiment with 65 MeV neutrons.
ERIC Educational Resources Information Center
Horenstein, Mary Ann
This booklet describes 12 Blue Ribbon secondary schools chosen during the 1991 federal recognition program. Representing a cross-section of America, these schools are characterized by a clear vision; empowered, hard-working teachers; a school environment that supports learning; use of local resources; and programs other than classroom learning.…
1958-07-01
down to Cote de ,’Ole (Map Neo 2) The attack was to be made by the 66th Brig- ado , with two battalions each of the 131st and 3.2nrd Infantry in line...Pannevoux had been heavily shelled with HE, yellow cross, and blue cross every nighto He Arko 95 order for 7 porno 3 Oct to 7 aomo 4 Oct (7th Rles Div
Lake Michigan Bluff Dewatering and Stabilization Study - Allegan County, Michigan
2012-09-01
laminated to cross- bedded sand interbedded with reddish brown, often laminated clay; and reddish-brown to gray to blue-gray diamicton (till) containing...Till also is extremely variable in thickness and may be a thin gravel lens, or up to 44 ft of graded sand beds , planar and trough cross- beds , thin...lies lacustrine clay to below lake level. The in-place layers are nominally flat , behind the slumped bluff face. ERDC TR-12-11 12 Figure 8
NASA Astrophysics Data System (ADS)
Ojha, Abhijeet; Thareja, Prachi
2018-03-01
In this study, we report the microstructure, rheology and adsorption characteristics of aqueous suspensions of Graphene Oxide (GO) at a volume fraction (ϕGO) = 0.018, which can be transformed into gels by cation induced charge shielding and cross-linking between GO nanosheets. GO nanosheets of average thickness ∼1.5 nm and a lateral dimension of ∼750 nm are synthesized by Hummer's process. At ϕGO= 0.018, cations of varying size and valence are systematically introduced with electrolytes NH4Cl, LiCl, NaCl, KCl, MgCl2 and FeCl3 at concentrations ranging from 10-5-10-1 M to investigate their effect on the rheology of GO suspensions. Our results suggest that depending on the electrolyte concentration, size and the valence of the cation: low viscosity suspensions, fragile gels and solid-like GO-electrolyte gels are formed. The storage modulus (G') of all GO-electrolyte gels increases with the increase in electrolyte concentration and G' follows the order GO-FeCl3 > GO-MgCl2> GO-KCl > GO-NaCl > GO-LiCl > GO-NH4Cl. FESEM analysis shows that lyophilized GO-electrolyte gels with 10-1 M electrolytes have a porous morphology resulting from the aggregation of GO nanosheets. The GO-electrolyte gels are shown to adsorb high quantities of oils, with GO-FeCl3 gels showing a higher adsorption capacity. The GO-NaCl and GO-FeCl3 lyophilized gels are also shown to adsorb methylene blue dye and follow the pseudo-second-order kinetics of adsorption. Along with higher oil and dye adsorption efficiency, GO-electrolyte gels are easy to recollect after the adsorption, thus avoiding the potential toxicity for bio-organisms in water caused by GO nanosheets.
Lazidou, Dimitra; Lampakis, Dimitrios; Karapanagiotis, Ioannis; Panayiotou, Costas
2018-01-01
The cross-section stratifications of samples, which were removed from six icons, are studied using optical microscopy, micro-Raman spectroscopy, and micro-Fourier transform infrared (FT-IR) spectroscopy. The icons, dated from the 14th to 19th centuries, are prominent examples of Byzantine painting art and are attributed to different artistic workshops of northern Greece. The following materials are identified in the cross-sections of the icon samples using micro-Raman spectroscopy: anhydrite; calcite; carbon black; chrome yellow; cinnabar; gypsum; lead white; minium; orpiment; Prussian blue; red ochre; yellow ochre; and a paint of organic origin which can be either indigo ( Indigofera tinctoria L. and others) or woad ( Isatis tinctoria L.). The same samples are investigated using micro-FT-IR which leads to the following identifications: calcite; calcium oxalates; chrome yellow; gypsum; kaolinite; lead carboxylates; lead sulfate (or quartz); lead white; oil; protein; Prussian blue; saponified oil; shellac; silica; and tree resin. The study of the cross-sections of the icon samples reveals the combinations of the aforementioned inorganic and organic materials. Although the icons span over a long period of six centuries, the same stratification comprising gypsum ground layer, paint layers prepared by modified "egg tempera" techniques (proteinaceous materials mixed with oil and resins), and varnish layer is revealed in the investigated samples. Moreover, the presence of three layers of varnishes, one at the top and other two as intermediate layers, in the cross-section analysis of a sample from Virgin and Child provide evidence of later interventions.
Inhibition of enamel remineralization with blue LED: an in vitro study
NASA Astrophysics Data System (ADS)
Kato, Ilka Tiemy; Mendes, Fausto Medeiros; Zezell, Denise Maria; Zanardi de Freitas, Anderson; Raele, Marcus Paulo; Wetter, Niklaus Ursus
2009-02-01
Blue light, especially from LED devices, is a tool very frequently used in dental procedures. However, the investigations of its effects on dental enamel are focused primarily on enamel demineralization and fluoride retention. Despite the fact that this spectral region can inhibit enamel demineralization, the consequences of the irradiation on demineralized enamel are not known. For this reason, we evaluated the effects of blue LED on enamel remineralization. Artificial lesions formed in bovine dental enamel samples by immersion in undersaturated acetate buffer were divided into three groups. In the first group (DE), the lesions were not submitted to any treatment. In the second (RE), the lesions were submitted to remineralization. The lesions from the third group (LED+RE) were irradiated with blue LED (455nm, 1.38W/cm2, 13.75J/cm2 and 10s) before the remineralization. Cross-sectional microhardness was used to assess mineral changes induced by remineralization under pH-cycling. The mineral deposition occurred preferably in the middle portion of the lesions. Specimens from group RE showed higher hardness value than the DE ones. On the other hand, the mean hardness value of the LED+RE samples was not statistically different from the DE samples. Results obtained in the present study show that the blue light is not innocuous for the dental enamel and inhibition of its remineralization can occur.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scibelli, Samantha; Newberg, Heidi Jo; Carlin, Jeffrey L.
We present a census of the 12,060 spectra of blue objects ((g – r){sub 0} < –0.25) in the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). As part of the data release, all of the spectra were cross-correlated with 48 template spectra of stars, galaxies, and QSOs to determine the best match. We compared the blue spectra by eye to the templates assigned in SDSS DR8. 10,856 of the objects matched their assigned template, 170 could not be classified due to low signal-to-noise ratio, and 1034 were given new classifications. We identify 7458 DA white dwarfs, 1145 DBmore » white dwarfs, 273 rarer white dwarfs (including carbon, DZ, DQ, and magnetic), 294 subdwarf O stars, 648 subdwarf B stars, 679 blue horizontal branch stars, 1026 blue stragglers, 13 cataclysmic variables, 129 white dwarf-M dwarf binaries, 36 objects with spectra similar to DO white dwarfs, 179, quasi-stellar objects (QSOs), and 10 galaxies. We provide two tables of these objects, sample spectra that match the templates, figures showing all of the spectra that were grouped by eye, and diagnostic plots that show the positions, colors, apparent magnitudes, proper motions, etc., for each classification. Future surveys will be able to use templates similar to stars in each of the classes we identify to automatically classify blue stars, including rare types.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scibelli, Samantha; Newberg, Heidi Jo; Carlin, Jeffrey L.
In this work, we present a census of the 12,060 spectra of blue objects (more » $$(g-r)_0<-0.25$$) in the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). As part of the data release, all of the spectra were cross-correlated with 48 template spectra of stars, galaxies and QSOs to determine the best match. We compared the blue spectra by eye to the templates assigned in SDSS DR8. 10,856 of the objects matched their assigned template, 170 could not be classified due to low signal-to-noise (S/N), and 1034 were given new classifications. We identify 7458 DA white dwarfs, 1145 DB white dwarfs, 273 rarer white dwarfs (including carbon, DZ, DQ, and magnetic), 294 subdwarf O stars, 648 subdwarf B stars, 679 blue horizontal branch stars, 1026 blue stragglers, 13 cataclysmic variables, 129 white dwarf - M dwarf binaries, 36 objects with spectra similar to DO white dwarfs, 179 QSOs, and 10 galaxies. We provide two tables of these objects, sample spectra that match the templates, figures showing all of the spectra that were grouped by eye, and diagnostic plots that show the positions, colors, apparent magnitudes, proper motions, etc. for each classification. In conclusion, future surveys will be able to use templates similar to stars in each of the classes we identify to classify blue stars, including rare types, automatically.« less
26Al Production in the Early Solar Nebula by Neutral High-Energy Plasma Winds
NASA Astrophysics Data System (ADS)
Spergel, M. S.
1995-09-01
In the light of recent observations, I believe that the sources for the presence of ^26Al within the solar nebula must be reconsidered [2,3]. Recent low observational estimates of the probability of encounters between mass-losing evolved stars and molecular clouds [4] for the production of ^26Al and the observed low production [5] of 26 Al from AGB (Asymptotic Giant Branch stars) along with the predicted low abundance of cosmic ray induced local production [6] in the early solar nebula all support continued investigation for additional sources of the solar nebula ^26Al presence. It is suggested based on the presences of new cross section data [7], that an important source of this ^26Al presence might be from enhanced interactions from the collisions of the local "T. Tauri" like plasma winds with the atomic and molecular Early Solar Nebula (ESN). Interactions like ^26Mg (p,n) ^26Al in this "neutral" electrical setting may provide the needed selective production. The ESN provides an environment where plasma winds can lead to such nucleosynthesis. Stellar winds of 300-700 km/s (about 3x10^7 K) are seen to T. Tauri like stars, presumed precursor to solar like stars, and also within the Solar heliosphere [8.9]. These winds provide the source of Solar High Energy Particles which can interact with such in situ targets such as ^26Mg to produce the ^26Al. The presence of the atomic and molecular environments, will enhance [10] nucleosynthesis over that seen in scattering of protons off bare nuclei. Such enhancement has been recently observed in low energy scattering on electrically shield targets [7]. There it was also suggested that in stellar convective zones, electron clouds of the plasma shield may also shield bare target nuclei. Measured values of low energy proton scattered on atomic and molecular targets indicated [7] that fusion cross sections are enlarged and elastic cross sections are reduced, therefore simple extrapolation of accelerator data can lead to an underestimate in the relevant excitation cross sections in lower energy proton induced production. Enhanced production in the ESN will be from the shielded atomic or molecular nuclei with the production increased by the product of this enhanced proton nucleosynthesis and the presence of the higher proton intensities for the lower energy particles available in the solar wind. References: [1] Supported under NIH-MARC grant #443789. [2] Clayton D. D. et al. (1977) Astrophys. J., 214, 300-315. [3] Clayton D. D. (1994) Nature, 368, 222-224. [4] Kastner J. H. and Myers P. C. (1994) Astrophys. J., 421, 605-614. [5] Prantzos N. (1993) Astrophys. J. Lett., 405, L55-L58. [6] Spergel M. S. (1995) Astrophys. Space Sci., 223, 187. [7] Castellani V. et al., The fate of Li and Be in stars and in the Laboratory, INFNFE-04-95 (preprint). [8] Simpson J. A. et al. (1995) Science, 268, 1019-1023. [9] Keppler E. et al. (1995) Science, 268, 1013-1016. [10] Rolfs C. E. and Rodney W. S. (1988) Cauldrons in the Cosmos (Nuclear Astrophysics), 165-168, Univ. of California.
Onset of ice VII phase during ps laser pulse propagation through liquid water
NASA Astrophysics Data System (ADS)
Kumar, V. Rakesh; Kiran, P. Prem
2017-01-01
Water dominantly present in liquid state on earth gets transformed to crystalline polymorphs under different dynamic loading conditions. Out of different crystalline phases discovered till date, ice VII is observed to be stable over wide pressure (2-63 GPa) and temperature (>273 K) ranges. The formation of ice VII crystalline structure has been vastly reported during high pressure static compression using diamond anvil cell and propagation of high energy (>50 mJ/pulse) nanosecond laser pulse induced dynamic high pressures through liquid water. We present the onset of ice VII phase at low threshold of 2 mJ/pulse during 30 ps (532 nm, 10 Hz) laser pulse induced shock propagating through liquid water. Role of input pulse energy on the evolution of Stoke's and anti-Stoke's Raman shift of the dominant A1g mode of ice VII, filamentation, free-electrons, plasma shielding is presented. The H-bond network rearrangement, electron ion energy transfer time coinciding with the excitation pulse duration supported by the filamentation and plasma shielding of the ps laser pulses reduced the threshold of ice VII structure formation. Filamentation and the plasma shielding have shown the localized creation and sustenance of ice VII structure in liquid water over 3 mm length and 50 μm area of cross-section.
Chen, Zhi; Kang, Shiliang; Zhang, Hang; Wang, Ting; Lv, Shichao; Chen, Qiuqun; Dong, Guoping; Qiu, Jianrong
2017-01-01
Optical modulation is a crucial operation in photonics for network data processing with the aim to overcome information bottleneck in terms of speed, energy consumption, dispersion and cross-talking from conventional electronic interconnection approach. However, due to the weak interactions between photons, a facile physical approach is required to efficiently manipulate photon-photon interactions. Herein, we demonstrate that transparent glass ceramics containing LaF3: Tm3+ (Er3+) nanocrystals can enable fast-slow optical modulation of blue/green up-conversion fluorescence upon two-step excitation of two-wavelengths at telecom windows (0.8–1.8 μm). We show an optical modulation of more than 1500% (800%) of the green (blue) up-conversion fluorescence intensity, and fast response of 280 μs (367 μs) as well as slow response of 5.82 ms (618 μs) in the green (blue) up-conversion fluorescence signal, respectively. The success of manipulating laser at telecom windows for fast-slow optical modulation from rear-earth single-doped glass ceramics may find application in all-optical fiber telecommunication areas. PMID:28368041
Do Red and Blue Uniforms Matter in Football and Handball Penalties?
Krenn, Bjoern; Pernhaupt, Niklas; Handsteiner, Markus
2017-12-01
Past research has revealed ambiguous results on the impact of red uniforms in sports competition. The current study was aimed at analyzing the role of red and blue uniforms in football and handball penalties. Two experiments were conducted using a within subjects design, where participants rated uniform color-manipulated video clips. In the first study, participants (n = 39) watched footage of football players kicking a penalty, whereas in the second study (n = 118) videos of handball penalty takers, handball goalkeepers and football goalkeepers preparing themselves to score/save a penalty were shown. Participants rated player's/goalkeeper's level of confidence and the expected position of the ball crossing the goal line in the first experiment and additionally the probability of scoring the penalty against the goalkeepers in the second experiment. The videos stopped at the point where the ball was leaving the foot and hand respectively. Results did not show any beneficial impact of red uniforms. Rather, football players wearing blue were rated to kick the ball higher. The study contradicts any positive effect of red versus blue uniforms in the context of football and handball penalties, which emphasizes the need of searching for potential moderators of color's impact on human behavior.
Macular lutein and zeaxanthin are related to brain lutein and zeaxanthin in primates
USDA-ARS?s Scientific Manuscript database
The xanthophyll pigments lutein and zeaxanthin cross the blood-retina barrier to preferentially accumulate in the macular region of the neural retina. There they form macular pigment, protecting the retina from blue light damage and oxidative stress. Lutein and zeaxanthin also accumulate in brain t...
133. View of rock cut at base of rough ridge ...
133. View of rock cut at base of rough ridge and roadway crossing unnamed viaduct on Grandfather Mountain with the Great Wall of China supporting the curve in the distance. Looking southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC
26 CFR 1.6662-4 - Substantial understatement of income tax.
Code of Federal Regulations, 2010 CFR
2010-04-01
...; General Explanations of tax legislation prepared by the Joint Committee on Taxation (the Blue Book... properly substantiated, or the taxpayer failed to keep adequate books and records with respect to the item... an understatement. (iv) Cross-reference. See § 1.6664-4(f) for certain rules regarding the...
Study of the Wall Paintings of the Cenador Del Leon in the Real Alcazar of Seville
NASA Astrophysics Data System (ADS)
Robador, Maria Dolores; Mancera, Inmaculada; Perez-Maqueda, Rafael; Albardonedo, Antonio
2017-10-01
The paintings on the walls of the Cenador del Leon located in the gardens of the Real Alcazar in Seville next to the Pabellon de Carlos V in the Jardin Ingles area have been studied. The components of the wall paintings cross-sections, which were prepared using small samples taken from the walls of Cenador del Leon, were characterized using infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis. The cross-sections of the collected samples indicated that the paint layer is well adhered to the preparation layer without any discontinuity, and only one carbonation layer exists at the top of the sequence of layers. These data suggest that the paint was applied on a fresco surface, and therefore, the adopted technique was fresco. Based on the different elements detected by EDX analysis of the cross-sections, the detected pigments included iron oxides accompanied by clay minerals (or earths) in the red pink, golden yellow and yellow colours, blue smelt for the blue colour and basic copper chloride (atacamite) for the green colour. In one sample, the particles were composed of Ba and S from barium sulphate and Ti and O from rutile titanium oxide due to a modern pigment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Watanabe, T.; Kunieda, S.; Shigyo, N.
The experimental technique for measurement of (n, xn) double differential cross sections for incident neutron energy above 100 MeV has been attempted to be developed with continuous-energy neutrons up to 400 MeV. Neutrons were produced in the spallation reaction by the 800 MeV proton beam, which was incident on a thick, heavily shielded tungsten target at the WNR facility at Los Alamos National Laboratory. The energies of incident neutrons were determined by the time-of-flight method. Emitted neutrons were detected by the recoil proton method. A phoswich detector consisting of NaI(Tl) and NE102A plastic scintillators was used for detecting recoil protons.more » We compared the preliminary experimental cross section data with the calculations by PHITS and QMD codes.« less
NASA Astrophysics Data System (ADS)
Hooper, Dan; McDermott, Samuel D.
2018-06-01
Due to shielding, direct detection experiments are in some cases insensitive to dark matter candidates with very large scattering cross sections with nucleons. In this paper, we revisit this class of models and derive a simple analytic criterion for conservative but robust direct detection limits. While large spin-independent cross sections seem to be ruled out, we identify potentially viable parameter space for dark matter with a spin-dependent cross section with nucleons in the range of 10-27 cm2≲σDM -p≲10-24 cm2 . With these parameters, cosmic-ray scattering with dark matter in the extended halo of the Milky Way could generate a novel and distinctive gamma-ray signal at high galactic latitudes. Such a signal could be observable by Fermi or future space-based gamma-ray telescopes.
The Michigan Spine Surgery Improvement Collaborative: a statewide Collaborative Quality Initiative.
Chang, Victor; Schwalb, Jason M; Nerenz, David R; Pietrantoni, Lisa; Jones, Sharon; Jankowski, Michelle; Oja-Tebbe, Nancy; Bartol, Stephen; Abdulhak, Muwaffak
2015-12-01
OBJECT Given the scrutiny of spine surgery by policy makers, spine surgeons are motivated to demonstrate and improve outcomes, by determining which patients will and will not benefit from surgery, and to reduce costs, often by reducing complications. Insurers are similarly motivated. In 2013, Blue Cross Blue Shield of Michigan (BCBSM) and Blue Care Network (BCN) established the Michigan Spine Surgery Improvement Collaborative (MSSIC) as a Collaborative Quality Initiative (CQI). MSSIC is one of the newest of 21 other CQIs that have significantly improved-and continue to improve-the quality of patient care throughout the state of Michigan. METHODS MSSIC focuses on lumbar and cervical spine surgery, specifically indications such as stenosis, disk herniation, and degenerative disease. Surgery for tumors, traumatic fractures, deformity, scoliosis, and acute spinal cord injury are currently not within the scope of MSSIC. Starting in 2014, MSSIC consisted of 7 hospitals and in 2015 included another 15 hospitals, for a total of 22 hospitals statewide. A standardized data set is obtained by data abstractors, who are funded by BCBSM/BCN. Variables of interest include indications for surgery, baseline patient-reported outcome measures, and medical history. These are obtained within 30 days of surgery. Outcome instruments used include the EQ-5D general health state score (0 being worst and 100 being the best health one can imagine) and EQ-5D-3 L. For patients undergoing lumbar surgery, a 0 to 10 numeric rating scale for leg and back pain and the Oswestry Disability Index for back pain are collected. For patients undergoing cervical surgery, a 0 to 10 numeric rating scale for arm and neck pain, Neck Disability Index, and the modified Japanese Orthopaedic Association score are collected. Surgical details, postoperative hospital course, and patient-reported outcome measures are collected at 90-day, 1-year, and 2-year intervals. RESULTS As of July 1, 2015, a total of 6397 cases have been entered into the registry. This number reflects 4824 eligible cases with confirmed surgery dates. Of these 4824 eligible cases, 3338 cases went beyond the 120-day window and were considered eligible for the extraction of surgical details, 90-day outcomes, and adverse events. Among these 3338 patients, there are a total of 2469 lumbar cases, 862 cervical cases, and 7 combined procedures that were entered into the registry. CONCLUSIONS In addition to functioning as a registry, MSSIC is also meant to be a platform for quality improvement with the potential for future initiatives and best practices to be implemented statewide in order to improve quality and lower costs. With its current rate of recruitment and expansion, MSSIC will provide a robust platform as a regional prospective registry. Its unique funding model, which is supported by BCBSM/BCN, will help ensure its longevity and viability, as has been observed in other CQIs that have been active for several years.
Rogers, Mary A M; Blumberg, Neil; Bernstein, Steven J; Flanders, Scott A; Chopra, Vineet
2016-12-01
Mechanisms of red blood cell delivery and their contribution to the incidence of venous thromboembolism are not well understood in the clinical setting. We assessed whether red blood cell transfusion through peripherally inserted central catheters (PICCs) affects the risk of venous thromboembolism compared with transfusion through non-PICC devices. We implemented a prospective study between Jan 1, 2013, and Sept 12, 2015, in patients (age ≥18 years) admitted to a general medicine ward or intensive care unit who received a PICC for any reason during clinical care in 47 hospitals in Michigan, USA, with a maximum follow-up of 70 days. The exposure of interest was route of red blood cell transfusion. The primary outcome was symptomatic, radiographically confirmed, deep-vein thrombosis in the arm or leg or pulmonary embolism. We used Cox proportional hazards regression for analyses. Venous thromboembolism developed in 482 (5%) of 10 604 patients with PICCs. Of 788 patients who received a red blood cell transfusion through a multi-lumen PICC, 61 had venous thromboembolism. The adjusted hazard ratio (HR) for venous thromboembolism in all patients whose transfusions were administered through a multi-lumen PICC was 1·96 (95% CI 1·47-2·61; p<0·0001) compared with patients not receiving a transfusion, and was 1·79 (1·09-2·95; p=0·022) compared with patients transfused through a peripheral intravenous line. Compared with delivery through a peripheral intravenous line, venous thromboembolism risk was not elevated if transfusions were delivered through a single-lumen PICC (HR 0·98, 95% CI 0·44-2·14; p=0·95) or central venous catheter (1·50, 0·77-2·91; p=0·23). For every red blood cell unit transfused through a PICC, there was a significantly increased risk of venous thromboembolism (adjusted HR 1·24, 95% CI 1·01-1·52; p=0·037). Patients who received a transfusion through a PICC in the left arm were significantly more likely to develop a deep-vein thrombosis in the ipsilateral arm compared with the contralateral side (HR 23·44, 95% CI 2·96-185·83; p=0·0028). Similarly, patients transfused through a right-sided PICC were more likely to develop deep-vein thrombosis in the ipsilateral arm (HR 3·37, 95% CI 1·02-11·14; p=0·047). Red blood cell delivery through a multi-lumen PICC is associated with a greater risk of thrombosis than transfusion through a peripheral intravenous catheter. Careful monitoring for venous thromboembolism when transfusing red blood cells through multi-lumen PICCs seems necessary. Blue Cross Blue Shield of Michigan and Blue Care Network, as part of the BCBSM Value Partnerships program. Copyright © 2016 Elsevier Ltd. All rights reserved.
Radiation detector based on a matrix of crossed wavelength-shifting fibers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kross, Brian J.; Weisenberger, Andrew; Zorn, Carl
A radiation detection system comprising a detection grid of wavelength shifting fibers with a volume of scintillating material at the intersecting points of the fibers. Light detectors, preferably Silicon Photomultipliers, are positioned at the ends of the fibers. The position of radiation is determined from data obtained from the detection grid. The system is easily scalable, customizable, and also suitable for use in soil and underground applications. An alternate embodiment employs a fiber grid sheet or layer which is comprised of multiple fibers secured to one another within the same plane. This embodiment further includes shielding in order to preventmore » radiation cross-talk within the grid layer.« less
NASA Astrophysics Data System (ADS)
dos Santos, J. F. M.; Terra, I. A. A.; Astrath, N. G. C.; Guimarães, F. B.; Baesso, M. L.; Nunes, L. A. O.; Catunda, T.
2015-02-01
Trivalent Tb-doped materials exhibit strong emission in the green and weak emission in the UV-blue levels. Usually, this behavior is attributed to the cross relaxation (CR) process. In this paper, the luminescence properties of Tb3+-doped low silica calcium aluminosilicate glasses are analyzed for UV (λexc = 325 nm) and visible (488 nm) excitations. Under 325 nm excitation, the intensity of green luminescence increases proportionally to Tb3+ concentration. However, the blue luminescence intensity is strongly reduced with the increase of concentration from 0.5-15.0 wt. %. In the case of 488 nm excitation, a saturation behavior of the green emission is observed at intensities two orders of magnitude smaller than expected for bleaching of the ground state population. Using a rate equation model, we showed that this behavior can be explained by an excited state absorption cross section two orders of magnitude larger than the ground state absorption. The blue emission is much weaker than expected from our rate equations (325 nm and 488 nm excitation). We concluded that only the CR process cannot explain the overall feature of measured luminescence quenching in the wide range of Tb3+ concentrations. Cooperative upconversion from a pair of excited ions (5D3:5D3 or 5D3:5D4) and other mechanisms involving upper lying states (4f5d, charge transfer, host matrix, defects, etc.) may play a significant role.
Fujishiro, Kaori; Stukovsky, Karen D Hinckley; Roux, Ana Diez; Landsbergis, Paul; Burchfiel, Cecil
2012-01-01
Objectives This study examines associations of occupation with smoking status, amount smoked among current- and former-smokers (number of cigarettes/day and lifetime cigarette consumption (pack-years)), and workplace exposure to environmental tobacco smoke (ETS) independent from income and education. Methods This is a cross-sectional analysis of data from a community sample (n=6355, age range: 45–84) using logistic and multinomial regression. All analyses were stratified by sex and adjusted for socio-demographic variables. Results Male blue-collar and sales/office workers had higher odds of having consumed >20 pack-years of cigarettes than managers/professionals. For both male and female current- or former-smokers, exposure to workplace ETS was consistently and strongly associated with heavy smoking and greater pack-years. Conclusions Blue-collar workplaces are associated with intense smoking and ETS exposure. Smoking must be addressed at both the individual- and workplace-levels especially in blue-collar workplaces. PMID:22261926
Blue phase-change recording at high data densities and data rates
NASA Astrophysics Data System (ADS)
Dekker, Martijn K.; Pfeffer, Nicola; Kuijper, Maarten; Ubbens, Igolt P.; Coene, Wim M. J.; Meinders, E. R.; Borg, Herman J.
2000-09-01
For the DVR system with the use of a blue laser diode (wavelength 405 nm) we developed (12 cm) discs with a total capacity of 22.4 GB. The land/groove track pitch is 0.30 micrometers and the channel bit length is 87 nm. The DVR system uses a d equals 1 code. These phase change discs can be recorded at continuous angular velocity at a maximum of 50 Mbps user data rate (including all format and ECC overhead) and meet the system specifications. Fast growth determined phase change materials (FGM) are used for the active layer. In order to apply these FGM discs at small track pitch special attention has been paid to the issue of thermal cross-write. Finally routes towards higher capacities such as advanced bit detection schemes and the use of a smaller track pitch are considered. These show the feasibility in the near future of at least 26.0 GB on a disc for the DVR system with a blue laser diode.
Fujishiro, Kaori; Stukovsky, Karen D Hinckley; Roux, Ana Diez; Landsbergis, Paul; Burchfiel, Cecil
2012-02-01
This study examines associations of occupation with smoking status, amount smoked among current and former smokers (number of cigarettes per day and lifetime cigarette consumption (pack-years)), and workplace exposure to environmental tobacco smoke (ETS) independent from income and education. This is a cross-sectional analysis of data from a community sample (n = 6355, age range: 45-84) using logistic and multinomial regression. All analyses were stratified by sex and adjusted for socio-demographic variables. Male blue-collar and sales/office workers had higher odds of having consumed more than 20 pack-years of cigarettes than managers/professionals. For both male and female current or former smokers, exposure to workplace ETS was consistently and strongly associated with heavy smoking and greater pack-years. Blue-collar workplaces are associated with intense smoking and ETS exposure. Smoking must be addressed at both the individual and workplace levels especially in blue-collar workplaces.
An Update of Recent Phits Code
NASA Astrophysics Data System (ADS)
Sihver, Lembit; Sato, Tatsuhiko; Niita, Koji; Iwase, Hiroshi; Iwamoto, Yosuke; Matsuda, Norihiro; Nakashima, Hiroshi; Sakamoto, Yukio; Gustafsson, Katarina; Mancusi, Davide
We will first present the current status of the General-Purpose Particle and Heavy-Ion Transport code System (PHITS). In particular, we will describe benchmarking of calculated cross sections against measurements; we will introduce a relativistically covariant version of JQMD, called R- JQMD, that features an improved ground-state initialization algorithm, and we will show heavyion charge-changing cross sections simulated with R-JQMD and compare them to experimental data and to results predicted by the JQMD model. We will also show calculations of dose received by aircrews and personnel in space from cosmic radiation. In recent years, many countries have issued regulations or recommendations to set annual dose limitations for aircrews. Since estimation of cosmic-ray spectra in the atmosphere is an essential issue for the evaluation of aviation doses we have calculated these spectra using PHITS. The accuracy of the simulation, which has well been verified by experimental data taken under various conditions, will be presented together with a software called EXPACS-V, that can visualize the cosmic-ray dose rates at ground level or at a certain altitude on the map of Google Earth, using the PHITS based Analytical Radiation Model in the Atmosphere (PARMA). PARMA can instantaneously calculate the cosmic-ray spectra anywhere in the world by specifying the atmospheric depth, the vertical cut-off rigidity and the force-field potential. For the purpose of examining the applicability of PHITS to the shielding design in space, the absorbed doses in a tissue equivalent water phantom inside an imaginary space vessel has been estimated for different shielding materials of different thicknesses. The results confirm previous results which indicate that PHITS is a suitable tool when performing shielding design studies of spacecrafts. Finally we have used PHITS for the calculations of depth-dose distributions in MATROSHKA, which is an ESA project dedicated to determining the radiation load on astronauts within and outside the International Space Station (ISS).
Double-layer neutron shield design as neutron shielding application
NASA Astrophysics Data System (ADS)
Sariyer, Demet; Küçer, Rahmi
2018-02-01
The shield design in particle accelerators and other high energy facilities are mainly connected to the high-energy neutrons. The deep penetration of neutrons through massive shield has become a very serious problem. For shielding to be efficient, most of these neutrons should be confined to the shielding volume. If the interior space will become limited, the sufficient thickness of multilayer shield must be used. Concrete and iron are widely used as a multilayer shield material. Two layers shield material was selected to guarantee radiation safety outside of the shield against neutrons generated in the interaction of the different proton energies. One of them was one meter of concrete, the other was iron-contained material (FeB, Fe2B and stainless-steel) to be determined shield thicknesses. FLUKA Monte Carlo code was used for shield design geometry and required neutron dose distributions. The resulting two layered shields are shown better performance than single used concrete, thus the shield design could leave more space in the interior shielded areas.
Physics of the Isotopic Dependence of Galactic Cosmic Ray Fluence Behind Shielding
NASA Technical Reports Server (NTRS)
Cucinotta, Francis A.; Saganti, Premkumar B.; Hu, Xiao-Dong; Kim, Myung-Hee Y.; Cleghorn, Timothy F.; Wilson, John W.; Tripathi, Ram K.; Zeitlin, Cary J.
2003-01-01
For over 25 years, NASA has supported the development of space radiation transport models for shielding applications. The NASA space radiation transport model now predicts dose and dose equivalent in Earth and Mars orbit to an accuracy of plus or minus 20%. However, because larger errors may occur in particle fluence predictions, there is interest in further assessments and improvements in NASA's space radiation transport model. In this paper, we consider the effects of the isotopic composition of the primary galactic cosmic rays (GCR) and the isotopic dependence of nuclear fragmentation cross-sections on the solution to transport models used for shielding studies. Satellite measurements are used to describe the isotopic composition of the GCR. Using NASA's quantum multiple-scattering theory of nuclear fragmentation (QMSFRG) and high-charge and energy (HZETRN) transport code, we study the effect of the isotopic dependence of the primary GCR composition and secondary nuclei on shielding calculations. The QMSFRG is shown to accurately describe the iso-spin dependence of nuclear fragmentation. The principal finding of this study is that large errors (plus or minus 100%) will occur in the mass-fluence spectra when comparing transport models that use a complete isotope grid (approximately 170 ions) to ones that use a reduced isotope grid, for example the 59 ion-grid used in the HZETRN code in the past, however less significant errors (less than 20%) occur in the elemental-fluence spectra. Because a complete isotope grid is readily handled on small computer workstations and is needed for several applications studying GCR propagation and scattering, it is recommended that they be used for future GCR studies.
An Algorithm for the Transport of Anisotropic Neutrons
NASA Technical Reports Server (NTRS)
Tweed, J.
2005-01-01
One major obstacle to human space exploration is the possible limitations imposed by the adverse effect of long-term exposure to the space environment. Even before human spaceflight began, the potentially brief exposure of astronauts to the very intense random solar particle events (SPE) were of great concern. A new challenge appears in deep space exploration from exposure to the low-intensity heavy-ion flux of the galactic cosmic rays (GCR) since the missions are of long duration and the accumulated GCR exposures can be high. Because cancer induction rates increase behind low to rather large thicknesses of aluminum shielding, according to available biological data on mammalian exposures to GCR like ions, the shield requirements for a Mars mission are prohibitively expensive in terms of mission launch costs. Therefore, a critical issue in the Human Exploration and Development of Space enterprise is cost effective mitigation of risk associated with ionizing radiation exposure. In order to estimate astronaut risk to GCR exposure and associated cancer risks and health hazards, it is necessary to do shield material studies. To determine an optimum radiation shield material it is necessary to understand nuclear interaction processes such as fragmentation and secondary particle production which is a function of energy dependent cross sections. This requires knowledge of material transmission characteristics either through laboratory testing or improved theoretical modeling. Here ion beam transport theory is of importance in that testing of materials in the laboratory environment generated by particle accelerators is a necessary step in materials development and evaluation for space use. The approximations used in solving the Boltzmann transport equation for the space setting are often not sufficient for laboratory work and those issues are a major emphasis of the present work.
NASA Technical Reports Server (NTRS)
Wincheski, Buzz; Fulton, Jim; Nath, Shridhar; Namkung, Min; Simpson, John
1993-01-01
Electromagnetic NDE techniques have in the past steered away from the use of ferromagnetic materials. Although their high permeabilities lead to increased field levels, the properties of ferrous elements in the presence of alternating magnetic fields are difficult to determine. In addition, their use leads to losses which can be minimized through the use of low conductivity ferrites. In fact, the eddy current probes which do incorporate ferromagnetic materials have focused on these losses and the shielding which can be obtained by surrounding a probe with a high permeability, conducting material. Eddy current probes enclosed in conducting and magnetic shields have been used to prevent the generated fields from interacting with materials in the vicinity of the probe, such as when testing near material boundaries. A recent invention has used ferromagnetic shielding to magnetically separate individual concentric eddy current probes in order to eliminate cross-talk between the probes so that simultaneous detection of different types of flaws at different depths can be achieved. In contrast to the previous uses of ferromagnetic materials purely as magnetic shields, an electromagnetic flaw detector recently developed at NASA Langley Research Center takes advantage of the flux focusing properties of a ferromagnetic mild steel in order to produce a simple, effective device for the non-destructive evaluation of conducting materials. The Flux Focusing Eddy Current Probe has been shown to accurately measure material thickness and fatigue damage. The straight forward flaw response of the probe makes the device ideal for rapid inspection of large structures, and has lead to its incorporation in a computer controlled search routine to locate fatigue crack tips and monitor experimental fatigue crack growth experiments.
NASA Astrophysics Data System (ADS)
Tyas, Luke Martin Graham
2012-05-01
SALT HRS (Southern African Large Telescope High Resolution Échelle Spectrograph) is a high-resolution, high-efficiency spectrograph for the 11m SALT telescope in Sutherland, South Africa. The initial optical design work was performed at the University of Canterbury, New Zealand. Revisions to the concept, the mechanical design, manufacture, assembly and testing have been handled by the Centre for Advanced Instrumentation, at Durham University in the United Kingdom. SALT HRS is a fibre-fed échelle grating spectrograph with four operational modes: low-, medium- and high-resolution and high-stability modes, having spectral resolutions of R≈16000, 37000, 67000 and 67000 respectively over a wavelength range of 370-890nm. The instrument is of a dual channel, 'white pupil' design, in which the primary mirror acts to collimate light onto a single R4 échelle grating, and also to focus dispersed light to an intermediate focus. A dichroic beam-splitter separates the dispersed light into two separate spectral channels. Spherical pupil mirrors transfer the separated beams via a fold mirror to two wavelength-specific volume-phase holographic gratings (VPHGs) used as cross-dispersers. Cross-dispersed spectra are then imaged by two fully dioptric camera systems onto optimized CCD detectors. This thesis presents the results of the laboratory testing and specification of several critical sub-systems of SALT HRS, as well as the development of key software tools for the design verification and operation at the telescope. In Chapter 1 we first review the technical development of high-resolution spectroscopy and its specific implementation in SALT HRS. In Chapter 2 we develop a comprehensive throughput model of the entire system based on a combination of as-built performance and specific throughput measurements in the laboratory. This is used to make some specific predictions for the on-sky performance of SALT HRS and the magnitude limits for science targets. We also present a graphical exposure time calculator based on these measurements which can be used by an astronomer to plan their observations with SALT HRS. Chapter 3 contains a detailed treatise on the optical fibre system of SALT HRS. Considerations for the use of optical fibres in astronomy are provided, as are details of an optional double scrambler, and the various instrument fibre modes. Extensive measurements of focal ratio degradation (FRD) are also presented, with testing of input beam speed; wavelength; fibre bending; variable pupil mirror illumination; and vacuum tank pressure dependency. The systems for fibre management are reviewed, as is the fibre bundle assembly process. Testing of two further sub-systems is described in Chapter 4. Firstly the long-term stability of the mirror mounting mechanisms is determined. The advantages of cross-dispersion of échelle spectra using volume-phase holographic gratings are then discussed, and the results of diffraction efficiency measurements are given for both red and blue channel gratings. Modern CCD technologies are examined in Chapter 5, and the blue detector is experimentally characterized using photon transfer and quantum efficiency curves. It is also used for an investigation into cosmic ray events in CCDs. Results from shielding the detector using lead are described, as is an attempt to distinguish the source of the events based on their morphology. Finally, Chapter 6 deals with the handling of data produced by SALT HRS. Methods of wavelength calibration of the spectra are discussed, including the use of Thorium-Argon lamps and an iodine absorption cell. The implementation of a Python based quick-look data reduction pipeline is reviewed, with a description of the processes performed. A summary of the thesis is given in Chapter 7.
Gazdik, Gertrude C.; Ross, Robert B.
1982-01-01
The area, on the crest of the Blue Ridge Mountains, is drained by small tributaries of the James River. Altitudes range from 600 ft where U.S. Route 501 crosses the James River to 3,073 ft on Highcock Knob.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-22
... * * * on the coverage options provided under [Medicare Advantage] in order to promote an active, informed..., National Hispanic Council on Aging; Stephen L. Fera, Vice President, Social Mission Programs, Independence Blue Cross; Clayton Fong, President and Chief Executive Officer, National Asian Pacific Center on Aging...
Red Crosses, Blue Water: Hospital Ships and China’s Expanding Naval Presence
2011-09-01
hospital ship sailed into Zhoushan harbor in the Yangtze River delta, officially joining the East Sea Fleet.66 The most prominent forerunners of the...the Yangtze Delta to some of the most remote outposts of the Chinese military in the Paracel (Xisha) and Spratly (Nansha) islands. In the course of
Graduate Student Blues: The Situation in Japan
ERIC Educational Resources Information Center
Pallos, Henrik; Yamada, Naoto; Okawa, Masako
2005-01-01
The aim of this study was to investigate the presence of emotional disturbance among Japanese graduate students and the underlying factors of their emotional disturbance. We conducted a cross sectional survey using the Japanese version of the 30-item General Health Questionnaire at 31 graduate schools from 12 university campuses in and around…
Teachers Make the Best Authors (Could You Be Next?)
ERIC Educational Resources Information Center
Bradbury, Judy
2006-01-01
This article features five classroom teachers who realized their publishing dreams. These teachers include Blue Balliet, author of "Chasing Vermeer" and ""The Wright Three," Patricia Reilly Giff, author of "Today Was a Terrible Day," Lily's Crossing," and "Pictures of Hollis Woods," Vicki Cobb, author of "I Face the Wind," and Science Experiments…
Thermally Cross-Linkable Hole Transport Materials for Solution Processed Phosphorescent OLEDs
NASA Astrophysics Data System (ADS)
Kim, Beom Seok; Kim, Ohyoung; Chin, Byung Doo; Lee, Chil Won
2018-04-01
Materials for unique fabrication of a solution-processed, multi-layered organic light-emitting diode (OLED) were developed. Preparation of a hole transport layer with a thermally cross-linkable chemical structure, which can be processed to form a thin film and then transformed into an insoluble film by using an amine-alcohol condensation reaction with heat treatment, was investigated. Functional groups, such as triplenylamine linked with phenylcarbazole or biphenyl, were employed in the chemical structure of the hole transport layer in order to maintain high triplet energy properties. When phenylcarbazole or biphenyl compounds continuously react with triphenylamine under acid catalysis, a chemically stable thin film material with desirable energy-level properties for a blue OLED could be obtained. The prepared hole transport materials showed excellent surface roughness and thermal stability in comparison with the commercial reference material. On the solution-processed model hole transport layer, we fabricated a device with a blue phosphorescent OLED by using sequential vacuum deposition. The maximum external quantum, 19.3%, was improved by more than 40% over devices with the commercial reference material (11.4%).
[Trial manufacture of a plunger shield for a disposable plastic syringe].
Murakami, Shigeki; Emoto, Takashi; Mori, Hiroshige; Fujita, Katsuhisa; Kubo, Naoki
2008-08-20
A syringe-type radiopharmaceutical being supplied by a manufacturer has a syringe shield and a plunger shield, whereas an in-hospital labeling radiopharmaceutical is administered by a disposable plastic syringe without the plunger shield. In cooperation with Nihon Medi-Physics Co. Ltd., we have produced a new experimental plunger shield for the disposable plastic syringe. In order to evaluate this shielding effect, we compared the leaked radiation doses of our plunger shield with those of the syringe-type radiopharmaceutical (Medi shield type). Our plunger shield has a lead plate of 21 mm in diameter and 3 mm thick. This shield is equipped with the plunger-end of a disposal plastic syringe. We sealed 99mTc solution into a plastic syringe (Terumo Co.) of 5 ml with our plunger shield and Medi shield type of 2 ml. We measured leaked radiation doses around syringes using fluorescent glass dosimeters (Dose Ace). The number of measure points was 18. The measured doses were converted to 70 microm dose equivalent at 740 MBq of radioactivity. The results of our plunger shield and the Medi shield type were as follows: 4-13 microSv/h and 3-14 microSv/h at shielding areas, 3-545 microSv/h and 6-97 microSv/h at non-shielding areas, 42-116 microSv/h and 88-165 microSv/h in the vicinity of the syringe shield, and 1071 microSv/h and 1243 microSv/h at the front of the needle. For dose rates of shielding areas around the syringe, the shielding effects were approximately the same as those of the Medi shield type. In conclusion, our plunger shield may be useful for reducing finger exposure during the injection of an in-hospital labeled radiopharmaceutical.
The discharge characteristics in nitrogen helicon plasma
NASA Astrophysics Data System (ADS)
Zhao, Gao; Wang, Huihui; Si, Xinlu; Ouyang, Jiting; Chen, Qiang; Tan, Chang
2017-12-01
Discharge characteristics of helicon plasma in nitrogen and argon-nitrogen mixtures were investigated experimentally by using a Langmuir probe, a B-dot probe, and an optical emission spectrum. Helicon wave discharge is confirmed by the changes of electron density and electromagnetic signal amplitude with the increasing RF power, which shows three discharge stages in nitrogen, corresponding to E-mode, H-mode, and W-mode discharges in helicon plasma, respectively. Discharge images in the radial cross section at different discharge modes through an intensified charge coupled device (ICCD) show a rapid increase in luminous intensity along with the RF power. When the nitrogen discharge is in the W-mode, the images show that the strongest luminance locates near the plasma boundary and no blue core appears in the axial center of tube, which is always observed in argon W-mode discharge. The "big blue" or blue core is a special character in helicon plasma, but it has not been observed in nitrogen helicon plasma. In nitrogen-argon mixtures, a weak blue core is observed in ICCD images since the nitrogen content is increased. The electric field turns to the periphery in the distribution of the radial field and the electron temperature decreases with the increasing nitrogen content, especially when the blue core disappears. The different behaviors of the electron impact and the energy consumption in nitrogen helicon plasma are suggested to be responsible for the decrease in electron energy and the change in the electric field distribution.
NASA Astrophysics Data System (ADS)
Guo, Rui; Hao, Cai-Na; Xia, X. Y.; Mao, Shude; Shi, Yong
2016-07-01
With the aim of exploring the fast evolutionary path from the blue cloud of star-forming galaxies to the red sequence of quiescent galaxies in the local universe, we select a local advanced merging infrared luminous and ultraluminous galaxy (adv-merger (U)LIRGs) sample and perform careful dust extinction corrections to investigate their positions in the star formation rate-M *, u - r, and NUV - r color-mass diagrams. The sample consists of 89 (U)LIRGs at the late merger stage, obtained from cross-correlating the Infrared Astronomical Satellite Point Source Catalog Redshift Survey and 1 Jy ULIRGs samples with the Sloan Digital Sky Survey DR7 database. Our results show that 74 % +/- 5 % of adv-merger (U)LIRGs are localized above the 1σ line of the local star-forming galaxy main sequence. We also find that all adv-merger (U)LIRGs are more massive than and as blue as the blue cloud galaxies after corrections for Galactic and internal dust extinctions, with 95 % +/- 2 % and 81 % +/- 4 % of them outside the blue cloud on the u - r and NUV - r color-mass diagrams, respectively. These results, combined with the short timescale for exhausting the molecular gas reservoir in adv-merger (U)LIRGs (3× {10}7 to 3× {10}8 years), imply that the adv-merger (U)LIRGs are likely at the starting point of the fast evolutionary track previously proposed by several groups. While the number density of adv-merger (U)LIRGs is only ˜ 0.1 % of the blue cloud star-forming galaxies in the local universe, this evolutionary track may play a more important role at high redshift.
Herr, Raphael M; Bosch, Jos A; Loerbroks, Adrian; van Vianen, Annelies E M; Jarczok, Marc N; Fischer, Joachim E; Schmidt, Burkhard
2015-11-01
Musculoskeletal pain has been found to co-occur with psychosocial job stress. However, different conceptualizations of job stress exist, each emphasizing different aspects of the work environment, and it is unknown which of these aspects show the strongest associations with musculoskeletal pain. Further, these associations may differ for white-collar vs. blue-collar job types, but this has not been tested. The present study examined the independent and combined contributions of Effort-RewardImbalance (ERI), Job-Demand-Control (JDC) and Organizational Justice (OJ) to musculoskeletal pain symptoms among white- and blue-collar workers. Participants of a cross-sectional study (n=1634) completed validated questionnaires measuring ERI, JDC, and OJ, and reported the frequency of pain during the previous year at four anatomical locations (lower back, neck or shoulder, arms and hands, and knees/feet). Pain reports were summarized into a single musculoskeletal symptom score (MSS). Analyses were stratified for white- and blue-collar workers. Among white-collar workers, ERI and OJ were independently associated with MSS. In addition to these additive effects, significant 2-way and 3-way interactions indicated a synergistic effect of job stressors in relation to reported pain. In blue-collar workers, ERI and JDC independently associated with MSS, and a significant 3-way interaction was observed showing that the combination of job stressors exceeded an additive effect. ERI influences pain symptoms in both occupational groups. OJ was independent significant predictor only among white-collar workers, whereas JDC had additive predictive utility exclusively among blue-collar workers. Simultaneous exposure to multiple job stress factors appeared to synergize pain symptom reporting. Copyright © 2015. Published by Elsevier Inc.
Wigner, E.P.
1958-04-22
A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.
Vince, D J; Culham, J A
1989-03-01
A prosthesis constructed with a fatigued steel helix encased in a silicone rubber shield was used to band the main pulmonary artery in 10 dogs. After a mean duration of 138 days the banded site was dilated with a 20 mm diameter angioplasty catheter. This dilatation produced a mean increase of 44.3% in the cross-sectional area. A further mean increase of 2.2% in the cross-sectional area was measured 137 days after the dilatation. In five uncomplicated experiments a second dilatation was performed with a 23 mm diameter angioplasty catheter after a mean interval of 140 days. The second dilatation produced a further 21% increase in the cross-sectional area. In the five experiments in which two dilatations were performed, there was a total increase in the mean cross-sectional area of 94% produced 273 days after banding. This prosthesis maintains banding of the main pulmonary artery and can be serially dilated by balloon angioplasty.
What color should glacier algae be? An ecological role for red carbon in the cryosphere.
Dial, Roman J; Ganey, Gerard Q; Skiles, S McKenzie
2018-03-01
Red-colored secondary pigments in glacier algae play an adaptive role in melting snow and ice. We advance this hypothesis using a model of color-based absorption of irradiance, an experiment with colored particles in snow, and the natural history of glacier algae. Carotenoids and phenols-astaxanthin in snow-algae and purpurogallin in ice-algae-shield photosynthetic apparatus by absorbing overabundant visible wavelengths, then dissipating the excess radiant energy as heat. This heat melts proximal ice crystals, providing liquid-water in a 0°C environment and freeing up nutrients bound in frozen water. We show that purple-colored particles transfer 87%-89% of solar energy absorbed by black particles. However, red-colored particles transfer nearly as much (85%-87%) by absorbing peak solar wavelengths and reflecting the visible wavelengths most absorbed by nearby ice and snow crystals; this latter process may reduce potential cellular overheating when snow insulates cells. Blue and green particles transfer only 80%-82% of black particle absorption. In the experiment, red-colored particles melted 87% as much snow as black particles, while blue particles melted 77%. Green-colored snow-algae naturally occupy saturated snow where water is non-limiting; red-colored snow-algae occupy drier, water-limited snow. In addition to increasing melt, we suggest that esterified astaxanthin in snow-alga cells increases hydrophobicity to remain surficial. © FEMS 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Measurement of the neutron-capture cross section on 63,65Cu between 0.4 and 7.5 MeV
NASA Astrophysics Data System (ADS)
Bray, Isabel; Bhike, Megha; Krishichayan, (None); Tornow, W.
2015-10-01
Copper is currently being used as a cooling and shielding material in most experimental searches for 0 ν β β decay. In order to accurately interpret background events in these experiments, the cross section of neutron-induced reactions on copper must be known. The purpose of this work was to measure the cross section of the 63,65Cu(n, γ)64,66Cu reactions. Data were collected through the activation method at a range of energies from approximately 0.4 MeV to 7.5 MeV, employing the neutron production reactions 3H(p,n)3Heand2H(d,n)3He. Previous data were limited to energies below approximately 3 MeV. The results are compared to predictions from the nuclear data libraries ENDF/B-VII.1 and TENDL-2014.
Thermal neutron radiative capture cross-section of 186W(n, γ)187W reaction
NASA Astrophysics Data System (ADS)
Tan, V. H.; Son, P. N.
2016-06-01
The thermal neutron radiative capture cross section for 186W(n, γ)187W reaction was measured by the activation method using the filtered neutron beam at the Dalat research reactor. An optimal composition of Si and Bi, in single crystal form, has been used as neutron filters to create the high-purity filtered neutron beam with Cadmium ratio of Rcd = 420 and peak energy En = 0.025 eV. The induced activities in the irradiated samples were measured by a high resolution HPGe digital gamma-ray spectrometer. The present result of cross section has been determined relatively to the reference value of the standard reaction 197Au(n, γ)198Au. The necessary correction factors for gamma-ray true coincidence summing, and thermal neutron self-shielding effects were taken into account in this experiment by Monte Carlo simulations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hooper, Dan; McDermott, Samuel D.
Due to shielding, direct detection experiments are in some cases insensitive to dark matter candidates with very large scattering cross sections with nucleons. In this paper, we revisit this class of models, and derive a simple analytic criterion for conservative but robust direct detection limits. While large spin-independent cross sections seem to be ruled out, we identify potentially viable parameter space for dark matter with a spin-dependent cross section with nucleons in the range ofmore » $$10^{-27} {\\rm cm}^2 < \\sigma_{{\\rm DM}-p} < 10^{-24} \\, {\\rm cm}^{2}$$. With these parameters, cosmic-ray scattering with dark matter in the extended halo of the Milky Way could generate a novel and distinctive gamma-ray signal at high galactic latitudes. Such a signal could be observable by Fermi or future space-based gamma-ray telescopes.« less
NASA Astrophysics Data System (ADS)
Iwamoto, Hiroki; Meigo, Shin-ichiro
2017-09-01
The impact of different spallation models implemented in the particle transport code PHITS on the shielding design of Transmutation Experimental Facility is investigated. For 400-MeV proton incident on a lead-bismuth eutectic target, an effective dose rate at the end of a thick radiation shield (3-m-thick iron and 3-m-thick concrete) calculated by the Liège intranuclear cascade (INC) model version 4.6 (INCL4.6) coupled with the GEMcode (INCL4.6/GEM) yields about twice as high as the Bertini INC model (Bertini/GEM). A comparison with experimental data for 500-MeV proton incident on a thick lead target suggest that the prediction accuracy of INCL4.6/GEM would be better than that of Bertini/GEM. In contrast, it is found that the dose rates in beam ducts in front of targets calculated by the INCL4.6/GEMare lower than those by the Bertini/GEM. Since both models underestimate the experimental results for neutron-production doubledifferential cross sections at 180° for 140-MeV proton incident on carbon, iron, and gold targets, it is concluded that it is necessary to allow a margin for uncertainty caused by the spallation models, which is a factor of two, in estimating the dose rate induced by neutron streaming through a beam duct.
Boron filled siloxane polymers for radiation shielding
NASA Astrophysics Data System (ADS)
Labouriau, Andrea; Robison, Tom; Shonrock, Clinton; Simmonds, Steve; Cox, Brad; Pacheco, Adam; Cady, Carl
2018-03-01
The purpose of the present work was to evaluate changes to structure-property relationships of 10B filled siloxane-based polymers when exposed to nuclear reactor radiation. Highly filled polysiloxanes were synthesized with the intent of fabricating materials that could shield high neutron fluences. The newly formulated materials consisted of cross-linked poly-diphenyl-methylsiloxane filled with natural boron and carbon nanofibers. This polymer was chosen because of its good thermal and chemical stabilities, as well as resistance to ionizing radiation thanks to the presence of aromatic groups in the siloxane backbone. Highly isotopically enriched 10B filler was used to provide an efficient neutron radiation shield, and carbon nanofibers were added to improve mechanical strength. This novel polymeric material was exposed in the Annular Core Research Reactor (ACRR) at Sandia National Labs to five different neutron/gamma fluxes consisting of very high neutron fluences within very short time periods. Thermocouples placed on the specimens recorded in-situ temperature changes during radiation exposure, which agreed well with those obtained from our MCNP simulations. Changes in the microstructural, thermal, chemical, and mechanical properties were evaluated by SEM, DSC, TGA, FT-IR NMR, solvent swelling, and uniaxial compressive load measurements. Our results demonstrate that these newly formulated materials are well-suitable to be used in applications that require exposure to different types of ionizing conditions that take place simultaneously.
Production of medical radioactive isotopes using KIPT electron driven subcritical facility.
Talamo, Alberto; Gohar, Yousry
2008-05-01
Kharkov Institute of Physics and Technology (KIPT) of Ukraine in collaboration with Argonne National Laboratory (ANL) has a plan to construct an electron accelerator driven subcritical assembly. One of the facility objectives is the production of medical radioactive isotopes. This paper presents the ANL collaborative work performed for characterizing the facility performance for producing medical radioactive isotopes. First, a preliminary assessment was performed without including the self-shielding effect of the irradiated samples. Then, more detailed investigation was carried out including the self-shielding effect, which defined the sample size and location for producing each medical isotope. In the first part, the reaction rates were calculated as the multiplication of the cross section with the unperturbed neutron flux of the facility. Over fifty isotopes have been considered and all transmutation channels are used including (n, gamma), (n, 2n), (n, p), and (gamma, n). In the second part, the parent isotopes with high reaction rate were explicitly modeled in the calculations. Four irradiation locations were considered in the analyses to study the medical isotope production rate. The results show the self-shielding effect not only reduces the specific activity but it also changes the irradiation location that maximizes the specific activity. The axial and radial distributions of the parent capture rates have been examined to define the irradiation sample size of each parent isotope.
Boron Filled Siloxane Polymers for Radiation Shielding
Labouriau, Andrea; Robison, Tom; Shonrock, Clinton Otto; ...
2017-09-01
The purpose of the present work was to evaluate changes to structure-property relationships of 10B filled siloxane-based polymers when exposed to nuclear reactor radiation. Highly filled polysiloxanes were synthesized with the intent of fabricating materials that could shield high neutron fluences. The newly formulated materials consisted of cross-linked poly-diphenyl-methylsiloxane filled with natural boron and carbon nanofibers. This polymer was chosen because of its good thermal and chemical stabilities, as well as resistance to ionizing radiation thanks to the presence of aromatic groups in the siloxane backbone. Highly isotopically enriched 10B filler was used to provide an efficient neutron radiation shield,more » and carbon nanofibers were added to improve mechanical strength. This novel polymeric material was exposed in the Annular Core Research Reactor (ACRR) at Sandia National Labs to five different neutron/gamma fluxes consisting of very high neutron fluences within very short time periods. Thermocouples placed on the specimens recorded in-situ temperature changes during radiation exposure, which agreed well with those obtained from our MCNP simulations. Changes in the microstructural, thermal, chemical, and mechanical properties were evaluated by SEM, DSC, TGA, FT-IR NMR, solvent swelling, and uniaxial compressive load measurements. In conclusion, our results demonstrate that these newly formulated materials are well-suitable to be used in applications that require exposure to different types of ionizing conditions that take place simultaneously.« less
Boron Filled Siloxane Polymers for Radiation Shielding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Labouriau, Andrea; Robison, Tom; Shonrock, Clinton Otto
The purpose of the present work was to evaluate changes to structure-property relationships of 10B filled siloxane-based polymers when exposed to nuclear reactor radiation. Highly filled polysiloxanes were synthesized with the intent of fabricating materials that could shield high neutron fluences. The newly formulated materials consisted of cross-linked poly-diphenyl-methylsiloxane filled with natural boron and carbon nanofibers. This polymer was chosen because of its good thermal and chemical stabilities, as well as resistance to ionizing radiation thanks to the presence of aromatic groups in the siloxane backbone. Highly isotopically enriched 10B filler was used to provide an efficient neutron radiation shield,more » and carbon nanofibers were added to improve mechanical strength. This novel polymeric material was exposed in the Annular Core Research Reactor (ACRR) at Sandia National Labs to five different neutron/gamma fluxes consisting of very high neutron fluences within very short time periods. Thermocouples placed on the specimens recorded in-situ temperature changes during radiation exposure, which agreed well with those obtained from our MCNP simulations. Changes in the microstructural, thermal, chemical, and mechanical properties were evaluated by SEM, DSC, TGA, FT-IR NMR, solvent swelling, and uniaxial compressive load measurements. In conclusion, our results demonstrate that these newly formulated materials are well-suitable to be used in applications that require exposure to different types of ionizing conditions that take place simultaneously.« less
Mishima, Hajime; Sugaya, Hisashi; Nishino, Tomofumi; Yamazaki, Masashi
2016-01-01
The cementless stem Excia (B. Braun, Melsungen, Germany) implant has a rectangular cross-sectional shape with back-and-forth flanges and a plasma-sprayed, dicalcium phosphate dihydrate coating from the middle to proximal portion to increase initial fixation and early bone formation. Here, the conformity of the Excia stem to the femoral canal morphology was three-dimensionally assessed using computed tomography. Forty-three patients (45 hips) were examined after primary total hip arthroplasty with a mean follow-up of 27 ± 3 months (range: 24–36 months). Spot welds occurred at zone 2 in 16 hips and at zone 6 in 24 hips, with 83% (20/24 hips) of those occurring within 3 months after surgery. First- (n = 12 hips), second- (n = 32), and third- (n = 1) degree stress shielding were observed. The stem was typically in contact with the cortical bone in the anterolateral mid-portion (100%) and posteromedial distal portions (85%). Stress shielding did not progress, even in cases where the stems were in contact with the distal portions. The anterior flange was in contact with the bone in all cases. The stability of the mid-lateral portion with the dicalcium phosphate dihydrate coating and the anterior flange may have inhibited the progression of stress shielding beyond the second degree. PMID:26881087
Passive magnetic shielding in MRI-Linac systems.
Whelan, Brendan; Kolling, Stefan; Oborn, Brad M; Keall, Paul
2018-03-26
Passive magnetic shielding refers to the use of ferromagnetic materials to redirect magnetic field lines away from vulnerable regions. An application of particular interest to the medical physics community is shielding in MRI systems, especially integrated MRI-linear accelerator (MRI-Linac) systems. In these systems, the goal is not only to minimize the magnetic field in some volume, but also to minimize the impact of the shield on the magnetic fields within the imaging volume of the MRI scanner. In this work, finite element modelling was used to assess the shielding of a side coupled 6 MV linac and resultant heterogeneity induced within the 30 cm diameter of spherical volume (DSV) of a novel 1 Tesla split bore MRI magnet. A number of different shield parameters were investigated; distance between shield and magnet, shield shape, shield thickness, shield length, openings in the shield, number of concentric layers, spacing between each layer, and shield material. Both the in-line and perpendicular MRI-Linac configurations were studied. By modifying the shield shape around the linac from the starting design of an open ended cylinder, the shielding effect was boosted by approximately 70% whilst the impact on the magnet was simultaneously reduced by approximately 10%. Openings in the shield for the RF port and beam exit were substantial sources of field leakage; however it was demonstrated that shielding could be added around these openings to compensate for this leakage. Layering multiple concentric shield shells was highly effective in the perpendicular configuration, but less so for the in-line configuration. Cautious use of high permeability materials such as Mu-metal can greatly increase the shielding performance in some scenarios. In the perpendicular configuration, magnetic shielding was more effective and the impact on the magnet lower compared with the in-line configuration.
Passive magnetic shielding in MRI-Linac systems
NASA Astrophysics Data System (ADS)
Whelan, Brendan; Kolling, Stefan; Oborn, Brad M.; Keall, Paul
2018-04-01
Passive magnetic shielding refers to the use of ferromagnetic materials to redirect magnetic field lines away from vulnerable regions. An application of particular interest to the medical physics community is shielding in MRI systems, especially integrated MRI-linear accelerator (MRI-Linac) systems. In these systems, the goal is not only to minimize the magnetic field in some volume, but also to minimize the impact of the shield on the magnetic fields within the imaging volume of the MRI scanner. In this work, finite element modelling was used to assess the shielding of a side coupled 6 MV linac and resultant heterogeneity induced within the 30 cm diameter of spherical volume (DSV) of a novel 1 Tesla split bore MRI magnet. A number of different shield parameters were investigated; distance between shield and magnet, shield shape, shield thickness, shield length, openings in the shield, number of concentric layers, spacing between each layer, and shield material. Both the in-line and perpendicular MRI-Linac configurations were studied. By modifying the shield shape around the linac from the starting design of an open ended cylinder, the shielding effect was boosted by approximately 70% whilst the impact on the magnet was simultaneously reduced by approximately 10%. Openings in the shield for the RF port and beam exit were substantial sources of field leakage; however it was demonstrated that shielding could be added around these openings to compensate for this leakage. Layering multiple concentric shield shells was highly effective in the perpendicular configuration, but less so for the in-line configuration. Cautious use of high permeability materials such as Mu-metal can greatly increase the shielding performance in some scenarios. In the perpendicular configuration, magnetic shielding was more effective and the impact on the magnet lower compared with the in-line configuration.
Mesbahi, Asghar; Ghiasi, Hosein
2018-06-01
The shielding properties of ordinary concrete doped with some micro and nano scaled materials were studied in the current study. Narrow beam geometry was simulated using MCNPX Monte Carlo code and the mass attenuation coefficient of ordinary concrete doped with PbO 2 , Fe 2 O 3 , WO 3 and H 4 B (Boronium) in both nano and micro scales was calculated for photon and neutron beams. Mono-energetic beams of neutrons (100-3000 keV) and photons (142-1250 keV) were used for calculations. The concrete doped with nano-sized particles showed higher neutron removal cross section (7%) and photon attenuation coefficient (8%) relative to micro-particles. Application of nano-sized material in the composition of new concretes for dual protection against neutrons and photons are recommended. For further studies, the calculation of attenuation coefficients of these nano-concretes against higher energies of neutrons and photons and different particles are suggested. Copyright © 2018 Elsevier Ltd. All rights reserved.
Kerns, J.A.; Stone, R.R.; Fabyan, J.
1985-02-12
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.
Kerns, J.A.; Stone, R.R.; Fabyan, J.
1987-10-06
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines. 3 figs.
Kerns, John A.; Stone, Roger R.; Fabyan, Joseph
1987-01-01
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.
Estimation of neutron spectrum in the low-level gamma spectroscopy system using unfolding procedure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Knežević, D., E-mail: david.knezevic@df.uns.ac.rs; Jovančević, N.; Krmar, M.
2016-03-25
The radiation resulting from neutron interactions with Ge nuclei in active volume of HPGe detectors is one of the main concerns in low-level gamma spectroscopy measurements [1,2]. It is usually not possible to measure directly spectrum of neutrons which strike detector. This paper explore the possibility of estimation of neutron spectrum using measured activities of certain Ge(n,γ) and Ge(n,n’) reactions (obtained from low-level gamma measurements), available ENDF cross section data and unfolding procedures. In this work HPGe detector with passive shield made from commercial low background lead was used for the measurement. The most important objective of this study wasmore » to reconstruct muon induced neutron spectrum created in the shield of the HPGe detector. MAXED [3] and GRAVEL [4] algorithms for neutron spectra unfolding were used. The results of those two algorithms were compared and we analyzed the sensitivity of the unfolding procedure to the various input parameters.« less
Metal/dielectric/metal sandwich film for broadband reflection reduction
Jen, Yi-Jun; Lakhtakia, Akhlesh; Lin, Meng-Jie; Wang, Wei-Hao; Wu, Huang-Ming; Liao, Hung-Sheng
2013-01-01
A film comprising randomly distributed metal/dielectric/metal sandwich nanopillars with a distribution of cross-sectional diameters, displayed extremely low reflectance over the blue-to-red regime, when coated on glass and illuminated normally. When it is illuminated by normally incident light, this sandwich film (SWF) has a low extinction coefficient, its phase thickness is close to a negative wavelength in the blue-to-red spectral regime, and it provides weakly dispersive forward and backward impedances, so that reflected waves from the two faces of the SWF interfere destructively. Broadband reflection-reduction, over a wide range of incidence angles and regardless of the polarization state of the incident light, was observed when the SWF was deposited on polished silicon. PMID:23591704
CloudSat Image of Tropical Thunderstorms Over Africa
NASA Technical Reports Server (NTRS)
2006-01-01
[figure removed for brevity, see original site] Figure 1 CloudSat image of a horizontal cross-section of tropical clouds and thunderstorms over east Africa. The red colors are indicative of highly reflective particles such as water (rain) or ice crystals, which the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudS at Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The brown line below the image indicates the relative elevation of the land surface. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) visible image taken at nearly the same time.Ultrafast intersystem crossings in Fe-Co Prussian blue analogues
DOE Office of Scientific and Technical Information (OSTI.GOV)
van Veenendaal, Michel
Ultrafast spincrossover is studied in Fe-Co Prussian blue analogues using a dissipative quantum-mechanical model of a cobalt ion coupled to a breathing mode. All electronic interactions are treated on an equal footing. It is theoretically demonstrated that the divalent cobalt ion reaches 90% of the S = 3/2 value within 20 fs after photoexciting a low-spin Co 3+ ion by an iron-to-cobalt charge transfer. The doublet-to-quartet spin crossover is significantly faster than the oscillation period of the breathing mode. The system relaxes to the lowest manifold of divalent cobalt ( 4T 1) in 150-200 fs. In conclusion, strong oscillations inmore » spin-orbit coupling and the involvement of higher-lying quartets are found.« less
Ultrafast intersystem crossings in Fe-Co Prussian blue analogues
van Veenendaal, Michel
2017-07-27
Ultrafast spincrossover is studied in Fe-Co Prussian blue analogues using a dissipative quantum-mechanical model of a cobalt ion coupled to a breathing mode. All electronic interactions are treated on an equal footing. It is theoretically demonstrated that the divalent cobalt ion reaches 90% of the S = 3/2 value within 20 fs after photoexciting a low-spin Co 3+ ion by an iron-to-cobalt charge transfer. The doublet-to-quartet spin crossover is significantly faster than the oscillation period of the breathing mode. The system relaxes to the lowest manifold of divalent cobalt ( 4T 1) in 150-200 fs. In conclusion, strong oscillations inmore » spin-orbit coupling and the involvement of higher-lying quartets are found.« less
Secondary neutron-production cross sections from heavy-ioninteractions in composite targets.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heilbronn, L.; Iwata, Y.; Iwase,H.
Secondary neutron-production cross-sections have been measured from interactions of 290 MeV/nucleon C and 600 MeV/nucleon Ne in a target composed of simulated Martian regolith and polyethylene, and from 400 MeV/nucleon Ne interactions in wall material from the International Space Station. The data were measured between 5 and 80 deg in the laboratory. We report the double-differential cross sections, angular distributions, and total neutron-production cross sections from all three systems. The spectra from all three systems exhibit behavior previously reported in other heavy-ion, neutron production experiments; namely, a peak at forward angles near the energy corresponding to the beam velocity, withmore » the remaining spectra generated by pre-equilibrium and equilibrium processes. The double differential cross sections are fitted with a moving-source parameterization. Also reported are the data without corrections for neutron flux attenuation in the target and other intervening materials, and for neutron production in non-target materials near the target position. These uncorrected spectra are compared with SHIELD-HIT and PHITS transport model calculations. The transport model calculations reproduce the spectral shapes well, but, on average, underestimate the magnitudes of the cross sections.« less
Secondary neutron-production cross sections from heavy-ion interactions in composite targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heilbronn, L.; Iwata, Y.; Murakami, T.
Secondary neutron-production cross sections have been measured from interactions of 290 MeV/nucleon C and 600 MeV/nucleon Ne in a target composed of simulated Martian regolith and polyethylene, and from 400 MeV/nucleon Ne interactions in wall material from the International Space Station. The data were measured between 5 deg. and 80 deg. in the laboratory. We report the double-differential cross sections, angular distributions, and total neutron-production cross sections from all three systems. The spectra from all three systems exhibit behavior previously reported in other heavy-ion neutron-production experiments, namely, a peak at forward angles near the energy corresponding to the beam velocity,more » with the remaining spectra generated by pre-equilibrium and equilibrium processes. The double-differential cross sections are fitted with a moving-source parametrization. Also reported are the data without corrections for neutron flux attenuation in the target and other intervening materials and for neutron production in nontarget materials near the target position. These uncorrected spectra are compared with SHIELD-HIT and PHITS transport model calculations. The transport model calculations reproduce the spectral shapes well but, on average, underestimate the magnitudes of the cross sections.« less
Earliest Phanerozoic or latest Proterozoic fossils from the Arabian Shield
Cloud, P.; Awramik, S.M.; Morrison, K.; Hadley, D.G.
1979-01-01
We report here the first biologically definable fossils from pre-Saq (pre-Middle Cambrian) rocks of the Arabian Shield. They include the distinctive helically coiled tubular filaments of the oscillatorialean blue-green alga Obruchevella parva as well as two size classes of spheroidal unicells of uncertain affinity. Also present is the conical stromatolite Conophyton and unidentified stromatolites. All occur in cherty limestones of the Jubaylah Group, northern Saudi Arabia, a nonmarine to locally marine taphrogeosynclinal sequence that fills depressions along the northwest-trending Najd faults. Conophyton has heretofore been found only in strata older than about 680 Ma (except for puzzling records in modern hot springs) while Obruchevella is so far known only from rocks between about 680 and 470 Ma old. Thus it appears that the Jubaylah Group is close to the Proterozoic-Phanerozoic transition. The simple spheroidal nanno-fossils are not diagnostic as to age. Their relationships within what appears to be early diagenetic chert suggest a classical algal-mat association. The brecciated and microchanneled appearance of much of the fossiliferous rock, its locally dolomitic nature, and the prevalence of cryptalgalaminate favors a very shallow, locally turbulent, and perhaps episodically exposed marine or marginal marine setting. The Jubaylah Group lies unconformably beneath the Siq Sandstone (basal member of the Saq Sandstone) of medial Cambrian age, rests nonconformably on crystalline basement, and has yielded a K-Ar whole-rock age (on andesitic basalt) of ???540 Ma. To judge from the fossils, however, that age may be as much as 100 Ma or more too young. ?? 1979.
Protection of Hawaii's Observatories from Light Pollution
NASA Astrophysics Data System (ADS)
Wainscoat, Richard J.
2018-01-01
Maunakea Observatory, located on the island of Hawaii, is among the world darkest sites for astronomy. Strong efforts to preserve the dark night sky over the last forty years have proven successful. Artificial light presently adds only approximately 2% to the natural night sky brightness. The techniques being used to protect Maunakea from light pollution will be described, along with the challenges that are now being faced.Haleakala Observatory, located on the island of Maui, is also an excellent observing site, and is among the best sites in the United States. Lighting restrictions in Maui County are much weaker, and consequently, the night sky above Haleakala is less well protected. Haleakala is closer to Honolulu and the island of Oahu (population approximately 1 million), and the glow from Oahu makes the northwestern sky brighter.Much of the lighting across most of the United States, including Hawaii, is presently being converted to LED lighting. This provides an opportunity to replace existing poorly shielded lights with properly shielded LED fixtures, but careful spectral management is essential. It is critically important to only use LED lighting that is deficient in blue and green light. LED lighting also is easy to dim. Dimming of lights later at night, when there is no need for brighter lighting, is an important tool for reducing light pollution.Techniques used to protect astronomical observatories from light pollution are similar to the techniques that must be used to protect animals that are affected by light at night, such as endangered birds and turtles. These same techniques are compatible with recent human health related lighting recommendations from the American Medical Association.
Li, Xinggao; Yuan, Dajun
2016-01-01
China's largest cities like Beijing and Shanghai have seen a sharp increase in subway network development as a result of the rapid urbanization in the last decade. The cities are still expanding their subway networks now, and many shield tunnels are being or will be constructed in close proximity to the existing operational subway tunnels. The execution plans for the new nearby shield tunnel construction calls for the development of a safety control framework-a set of control standards and best practices to help organizations manage the risks involved. Typical case studies and relevant key technical parameters are presented with a view to presenting the resulting safety control framework. The framework, created through collaboration among the relevant parties, addresses and manages the risks in a systematic way based on actual conditions of each tunnel crossing construction. The framework consists of six parts: (1) inspecting the operational subway tunnels; (2) deciding allowed movements of the existing tunnels and tracks; (3) simulating effects of the shield tunneling on the existing tunnels; (4) doing preparation work; (5) monitoring design and information management; and (6) measures and activation mechanism of the countermeasures. The six components are explained and demonstrated in detail. In the end, discussions made involve construction and post-construction settlement of the operational tunnel, application of the remedial grouting to rectify excessive settlements of the operational tunnel, and use of the innovative tool of the optical fiber measurement for tunnel movement monitoring. It is concluded that the construction movement of the tunnel can be controlled within 15 mm when the shield machine is <7 m in excavation diameter. The post-construction settlement of the tunnel buried in the very soft ground is much greater than its construction settlement, and last several years until reaching a final stable state. Two cases are outlined to demonstrate the feasibility of using the remedial grouting to reduce the long-term settlement of the operational tunnels. The more and more segmental tunnels being constructed, there is an increasing need of the optical fiber measurement for tunnel movement monitoring in the near future.
USDA-ARS?s Scientific Manuscript database
Channel catfish (Ictalurus punctatus) represent the greatest market share in U.S. aquaculture production, both in terms of total economic value and numbers produced. The blue catfish (I. furcatus) is also of great interest to U.S. aquaculture, because interspecific crosses (I. punctatus x I. furcatu...
Ragunath, K; Krasner, N; Raman, V S; Haqqani, M T; Cheung, W Y
2003-12-01
The value of methylene blue-directed biopsies (MBDB) in detecting specialized intestinal metaplasia and dysplasia in Barrett's esophagus remains unclear. The aim of this study was to compare the accuracy of MBDB with random biopsy in detecting intestinal metaplasia and dysplasia in patients with Barrett's esophagus. A prospective, randomized, cross-over trial was undertaken to compare MBDB with random biopsy in patients with Barrett's esophagus segments 3 cm or more in length without macroscopic evidence of dysplasia or cancer. Dysplasia was graded as: indefinite for dysplasia, low-grade dysplasia, high-grade dysplasia, or carcinoma, and was reported in a blinded fashion. Fifty-seven patients were recruited, 44 of whom were male. A total of 1,269 biopsies were taken (MBDB-651, random biopsie-618). Analysis of the results by per-biopsy protocol showed that the MBDB technique diagnosed significantly more specialized intestinal metaplasia (75 %) compared to the random biopsy technique (68 %; P = 0.032). The sensitivity and specificity rates of MBDB for diagnosing specialized intestinal metaplasia were 91 % (95 % CI, 88 - 93 %) and 43 % (95 % CI, 36 - 51 %), respectively. The sensitivity and specificity rates of MBDB for diagnosing dysplasia or carcinoma were 49 % (95 % CI, 38 - 61 %) and 85 % (95 % CI, 82 - 88 %), respectively. There were no significant differences in the diagnosis of dysplasia and carcinoma - MBDB 12 %, random biopsy 10 %. The methylene blue staining pattern appeared to have an influence on the detection of specialized intestinal metaplasia and dysplasia/carcinoma. Dark blue staining was associated with increased detection of specialized intestinal metaplasia (P < 0.0001), and heterogeneous staining (P = 0.137) or no staining (P = 0.005) were associated with dysplasia and/or carcinoma detection. The MBDB technique prolonged the endoscopy examination by an average of 6 min. The diagnostic accuracy of the MBDB technique was superior to that of the random biopsy technique for identifying specialized intestinal metaplasia, but not dysplasia or carcinoma. The intensity of methylene blue staining has an influence on the detection of specialized intestinal metaplasia and dysplasia or carcinoma, which may help in targeting the biopsies. Although MBDB prolongs the endoscopy procedure slightly, it is a safe and well-tolerated procedure. Further clinical studies on the MBDB technique exclusively in endoscopically normal dysplastic Barrett's esophagus are needed.
Intercalated graphite fiber composites as EMI shields in aerospace structures
NASA Technical Reports Server (NTRS)
Gaier, James R.
1990-01-01
The requirements for electromagnetic interference (EMI) shielding in aerospace structures are complicated over that of ground structures by their weight limitations. As a result, the best EMI shielding materials must blend low density, high strength, and high elastic modulus with high shielding ability. In addition, fabrication considerations including penetrations and joints play a major role. The EMI shielding properties are calculated for shields formed from pristine and intercalated graphite fiber/epoxy composites and compared to preliminary experimental results and to shields made from aluminum. Calculations indicate that EMI shields could be fabricated from intercalated graphite composites which would have less than 12 percent of the mass of conventional aluminum shields, based on mechanical properties and shielding properties alone.