Planetary and Primitive Object Strength Measurement and Sampling Apparatus

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.

1995-01-01

Support is requested for continuation of a program of dynamic impact (harpoon) coring of planetary, comet, or asteroid surface materials. We have previously demonstrated that good quality cores are obtainable for planetary materials with compressive strengths less than 200 MPa. Since the dynamics of penetration are observable on a Discovery class spacecraft, which images the sampling operation, these data can be used with a model developed under this project, to measure in-situ strength and frictional strength of the crust of the object. During the last year we have developed a detailed analytic model of penetrator mechanics. Progress is reported for the solid penetrators experiments, the CIT penetrator model, and the impact spall sampling apparatus.

Penetration of nutrition information on food labels across the EU-27 plus Turkey

PubMed Central

Storcksdieck genannt Bonsmann, S; Celemín, L Fernández; Larrañaga, A; Egger, S; Wills, J M; Hodgkins, C; Raats, M M

2010-01-01

Objectives: The European Union (EU)-funded project Food Labelling to Advance Better Education for Life (FLABEL) aims to understand how nutrition information on food labels affects consumers' dietary choices and shopping behaviour. The first phase of this study consisted of assessing the penetration of nutrition labelling and related information on various food products in all 27 EU Member States and Turkey. Methods: In each country, food products were audited in three different types of retailers to cover as many different products as possible within five food and beverage categories: sweet biscuits, breakfast cereals, pre-packed chilled ready meals, carbonated soft drinks and yoghurts. Results: More than 37 000 products were audited in a total of 84 retail stores. On average, 85% of the products contained back-of-pack (BOP) nutrition labelling or related information (from 70% in Slovenia to 97% in Ireland), versus 48% for front-of-pack (FOP) information (from 24% in Turkey to 82% in the UK). The most widespread format was the BOP tabular or linear listing of nutrition content. Guideline daily amounts labelling was the most prevalent form of FOP information, showing an average penetration of 25% across all products audited. Among categories, breakfast cereals showed the highest penetration of nutrition-related information, with 94% BOP penetration and 70% FOP penetration. Conclusions: Nutrition labelling and related information was found on a large majority of products audited. These findings provide the basis for subsequent phases of FLABEL involving attention, reading, liking, understanding and use by consumers of different nutrition labelling formats. PMID:20808336

Correlation between the reason for referral, clinical, and objective assessment of the risk for dysphagia.

PubMed

Mancopes, Renata; Gonçalves, Bruna Franciele da Trindade; Costa, Cintia Conceição; Favero, Talita Cristina; Drozdz, Daniela Rejane Constantino; Bilheri, Diego Fernando Dorneles; Schumacher, Stéfani Fernanda

2014-01-01

To correlate the reason for referral to speech therapy service at a university hospital with the results of clinical and objective assessment of risk for dysphagia. This is a cross-sectional, observational, retrospective analytical and quantitative study. The data were gathered from the database, and the information used was the reason for referral to speech therapy service, results of clinical assessment of the risk for dysphagia, and also from swallowing videofluoroscopy. There was a mean difference between the variables of the reason for the referral, results of the clinical and objective swallowing assessments, and scale of penetration/aspiration, although the values were not statistically significant. Statistically significant correlation was observed between clinical and objective assessments and the penetration scale, with the largest occurring between the results of objective assessment and penetration scale. There was a correlation between clinical and objective assessments of swallowing and mean difference between the variables of the reason for the referral with their respective assessment. This shows the importance of the association between the data of patient's history and results of clinical evaluation and complementary tests, such as videofluoroscopy, for correct identification of the swallowing disorders, being important to combine the use of severity scales of penetration/aspiration for diagnosis.

Optimization of Deep Drilling Performance - Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alan Black; Arnis Judzis

2005-09-30

This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2004 through September 2005. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for amore » next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all Phase 1 testing and is planning Phase 2 development.« less

A Flexure-Guided Piezo Drill for Penetrating the Zona Pellucida of Mammalian Oocytes.

PubMed

Johnson, Wesley; Dai, Changsheng; Liu, Jun; Wang, Xian; Luu, Devin K; Zhang, Zhuoran; Ru, Changhai; Zhou, Chao; Tan, Min; Pu, Huayan; Xie, Shaorong; Peng, Yan; Luo, Jun; Sun, Yu

2018-03-01

Mammalian oocytes such as mouse oocytes have a highly elastic outer membrane, zona pellucida (ZP) that cannot be penetrated without significantly deforming the oocyte, even with a sharp micropipette. Piezo drill devices leverage lateral and axial vibration of the micropipette to accomplish ZP penetration with greatly reduced oocyte deformation. However, existing piezo drills all rely on a large lateral micropipette vibration amplitude ( 20 ) and a small axial vibration amplitude (0.1 ). The very large lateral vibration amplitude has been deemed to be necessary for ZP penetration although it also induces larger oocyte deformation and more oocyte damage. This paper reports on a new piezo drill device that uses a flexure guidance mechanism and a systematically designed pulse train with an appropriate base frequency. Both simulation and experimental results demonstrate that a small lateral vibration amplitude (e.g., 2 ) and an axial vibration amplitude as large as 1.2 were achieved. Besides achieving 100% effectiveness in the penetration of mouse oocytes (n = 45), the new piezo device during ZP penetration induced a small oocyte deformation of 3.4 versus larger than 10 using existing piezo drill devices.

Normal Anal Examination After Penetration: A Case Report.

PubMed

Slingsby, Brett; Goldberg, Amy

2018-03-01

Physical findings are rare after anal penetration. Furthermore, children delay in disclosing or are reticent to discuss penetration. A 12-year-old boy presented to medical care multiple times over a several-week period complaining of abdominal pain, bloody diarrhea, and poor appetite. On colonoscopy, he was found to have a cylindrical foreign body (measuring 7 cm tall and 7 cm in diameter) in his rectum, which had been present for at least 2 weeks. He initially denied knowing how the object got into his rectum and later stated that he inserted it himself out of curiosity. One week after the object was removed, follow-up examination using video colposcopy revealed a completely normal anal examination; the patient had a normal anal examination despite known anal penetration and removal of the object. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Children can have a normal anal examination despite anal penetration, and do not always disclose anal penetration. The aforementioned concepts can be applied to situations related to child sexual abuse in the emergency department, where physical examinations are frequently normal and children delay in disclosing the abuse. When there is concern for sexual abuse, even in the absence of a disclosure or examination findings, patients should be referred for a child abuse pediatrics evaluation if available. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigations on the sensitivity of a stepped-frequency radar utilizing a vector network analyzer for Ground Penetrating Radar

NASA Astrophysics Data System (ADS)

Seyfried, Daniel; Schubert, Karsten; Schoebel, Joerg

2014-12-01

Employing a continuous-wave radar system, with the stepped-frequency radar being one type of this class, all reflections from the environment are present continuously and simultaneously at the receiver. Utilizing such a radar system for Ground Penetrating Radar purposes, antenna cross-talk and ground bounce reflection form an overall dominant signal contribution while reflections from objects buried in the ground are of quite weak amplitude due to attenuation in the ground. This requires a large dynamic range of the receiver which in turn requires high sensitivity of the radar system. In this paper we analyze the sensitivity of our vector network analyzer utilized as stepped-frequency radar system for GPR pipe detection. We furthermore investigate the performance of increasing the sensitivity of the radar by means of appropriate averaging and low-noise pre-amplification of the received signal. It turns out that the improvement in sensitivity actually achievable may differ significantly from theoretical expectations. In addition, we give a descriptive explanation why our appropriate experiments demonstrate that the sensitivity of the receiver is independent of the distance between the target object and the source of dominant signal contribution. Finally, our investigations presented in this paper lead to a preferred setting of operation for our vector network analyzer in order to achieve best detection capability for weak reflection amplitudes, hence making the radar system applicable for Ground Penetrating Radar purposes.

Transtympanic Facial Nerve Paralysis: A Review of the Literature

PubMed Central

Schaefer, Nathan; O’Donohue, Peter; French, Heath; Griffin, Aaron; Gochee, Peter

2015-01-01

Summary: Facial nerve paralysis because of penetrating trauma through the external auditory canal is extremely rare, with a paucity of published literature. The objective of this study is to review the literature on transtympanic facial nerve paralysis and increase physician awareness of this uncommon injury through discussion of its clinical presentation, management and prognosis. We also aim to improve patient outcomes in those that have sustained this type of injury by suggesting an optimal management plan. In this case report, we present the case of a 46-year-old white woman who sustained a unilateral facial nerve paresis because of a garfish penetrating her tympanic membrane and causing direct damage to the tympanic portion of her facial nerve. On follow-up after 12 months, her facial nerve function has largely returned to normal. Transtympanic facial nerve paralysis is a rare injury but can have a favorable prognosis if managed effectively. PMID:26090278

Meteoroid, and debris special investigation group preliminary results: Size-frequency distribution and spatial density of large impact features on LDEF

NASA Technical Reports Server (NTRS)

See, Thomas H.; Hoerz, Friedrich; Zolensky, Michael E.; Allbrooks, Martha K.; Atkinson, Dale R.; Simon, Charles G.

1992-01-01

All craters greater than or equal to 500 microns and penetration holes greater than or equal to 300 microns in diameter on the entire Long Duration Exposure Facility (LDEF) were documented. Summarized here are the observations on the LDEF frame, which exposed aluminum 6061-T6 in 26 specific directions relative to LDEF's velocity vector. In addition, the opportunity arose to characterize the penetration holes in the A0178 thermal blankets, which pointed in nine directions. For each of the 26 directions, LDEF provided time-area products that approach those afforded by all previous space-retrieved materials combined. The objective here is to provide a factual database pertaining to the largest collisional events on the entire LDEF spacecraft with a minimum of interpretation. This database may serve to encourage and guide more interpretative efforts and modeling attempts.

Is Managed Care Leading to Consolidation in Health-care Markets?

PubMed Central

David, Dranove; Simon, Carol J; White, William D

2002-01-01

Objective To determine the extent to which managed care has led to consolidation among hospitals and physicians. Data Sources We use data from the American Hospital Association, American Medical Association, and government censuses. Study Design Two stage least squares regression analysis examines how cross-section variation in managed care penetration affects provider consolidation, while controlling for the endogeneity of managed-care penetration. Specifically, we examine inpatient hospital markets and physician practice size in large metropolitan areas. Data Collection Methods All data are from secondary sources, merged at the level of the Primary Metropolitan Statistical Area. Principal Findings We find that higher levels of local managed-care penetration are associated with substantial increases in consolidation in hospital and physician markets. In the average market (managed-care penetration equaled 34 percent in 1994), managed care was associated with an increase in the Herfindahl of .054 between 1981 and 1994, moving from .096 in 1981 to .154. This is equivalent to moving from 10.4 equal-size hospitals to 6.5 equal-sized hospitals. In the physician market place, we estimate that at the mean, managed care resulted in a 14 percentage point decrease of physicians in solo practice between 1986 and 1995. This implies a decrease in the percentage of doctors in solo practice from 38 percent in 1986 to 24 percent by 1995. PMID:12132596

The Development of a Beta-Gamma Personnel Dosimeter

NASA Astrophysics Data System (ADS)

Tsakeres, Frank Steven

The assessment of absorbed dose in mixed beta and gamma radiation fields is an extremely complex task. For many years, the assessment of the absorbed dose to tissue from the weakly penetrating components of a radiation field (i.e., beta particles, electrons) has been largely ignored. Beta radiation fields are encountered routinely in a nuclear facility and may represent the major radiation component under certain accident or emergency conditions. Many attempts have been made to develop an accurate mixed field personnel dosimeter. However, all of these dosimeters have exhibited numerous response problems which have limited their usefulness for personnel dose assessment. Consequently, the determination of the absorbed dose at the epidermal depth (i.e., 7 mg/cm('2)) has been difficult to measure accurately. The objective of this research project was to design, build, and test a sensitive and accurate personnel dosimeter for mixed field applications. The selection of the various dosimeter elements were determined by evaluating several types of phosphors, filters, and backscatter materials. After evaluating the various response characteristics of the badge components, a prototype dosimeter, the CHEMM (CaF(,2):Dy Highly Efficient Multiple Element Multiple Filter) personnel dosimeter, was developed and tested at Georgia Tech, Emory University and the National Bureau of Standards. This dosimeter was comprised of four large CaF(,2):Dy (TLD-200) TLD's and a standard LiF (TLD-100) chip. The weakly penetrating and penetrating components of a radiation field were separated using a series of TLD/filter combinations and a new dose assessment algorithm. The large TLD-200 chips, along with a series of tissue-equivalent filters, were used to determine the absorbed dose due to the weakly penetrating radiation while a LiF/filter combination was used to measure the penetrating component. In addition, a new backscatter material was included in the badge design to better simulate a tissue-equivalent response. The CHEMM personnel dosimeter performance tests were conducted to simulate actual mixed radiation field environments. This dosimeter provided a high degree of sensitivity with accuracies well within the ANSI recommended performance standards for personnel dosimeters. In addition, it was concluded that the CHEMM dosimetry system provided a practical dosimeter alternative with a higher dose assessment accuracy and measurement sensitivity than the personnel dosimetry systems presently used in the nuclear power industry.

Evaluation of a pneumatic Martian soil sampler concept

NASA Technical Reports Server (NTRS)

Schaefer, John L.; Neathery, James K.; Stencel, John M.

1994-01-01

The pneumatic soil sampler concept was successfully demonstrated by penetrating a Martian simulant soil to a depth of 2 meters. Working gas pressure, composition, and pulsing were evaluated with the objective of minimizing gas usage. Also, the probe penetration force was investigated with the objective of minimizing probe weight. Gas and probe penetration force, while not yet optimized, are within the range which make the soil sampler concept feasible. While the tests described in this report did not answer all the questions and address all the variables associated with pneumatic soil sampling, valuable data experience and knowledge were gained which can be used to further develop the concept.

Detection of shallow buried objects using an autoregressive model on the ground penetrating radar signal

NASA Astrophysics Data System (ADS)

Nabelek, Daniel P.; Ho, K. C.

2013-06-01

The detection of shallow buried low-metal content objects using ground penetrating radar (GPR) is a challenging task. This is because these targets are right underneath the ground and the ground bounce reflection interferes with their detections. They do not create distinctive hyperbolic signatures as required by most existing GPR detection algorithms due to their special geometric shapes and low metal content. This paper proposes the use of the Autoregressive (AR) modeling method for the detection of these targets. We fit an A-scan of the GPR data to an AR model. It is found that the fitting error will be small when such a target is present and large when it is absent. The ratio of the energy in an Ascan before and after AR model fitting is used as the confidence value for detection. We also apply AR model fitting over scans and utilize the fitting residual energies over several scans to form a feature vector for improving the detections. Using the data collected from a government test site, the proposed method can improve the detection of this kind of targets by 30% compared to the pre-screener, at a false alarm rate of 0.002/m2.

Obstacle penetrating dynamic radar imaging system

DOEpatents

Romero, Carlos E [Livermore, CA; Zumstein, James E [Livermore, CA; Chang, John T [Danville, CA; Leach, Jr Richard R. [Castro Valley, CA

2006-12-12

An obstacle penetrating dynamic radar imaging system for the detection, tracking, and imaging of an individual, animal, or object comprising a multiplicity of low power ultra wideband radar units that produce a set of return radar signals from the individual, animal, or object, and a processing system for said set of return radar signals for detection, tracking, and imaging of the individual, animal, or object. The system provides a radar video system for detecting and tracking an individual, animal, or object by producing a set of return radar signals from the individual, animal, or object with a multiplicity of low power ultra wideband radar units, and processing said set of return radar signals for detecting and tracking of the individual, animal, or object.

High penetrance of pheochromocytoma associated with the novel C634Y/Y791F double germline mutation in the RET protooncogene.

PubMed

Toledo, Rodrigo A; Wagner, Simona M; Coutinho, Flavia L; Lourenço, Delmar M; Azevedo, Juliana A; Longuini, Viviane C; Reis, Mariana T A; Siqueira, Sheila A C; Lucon, Antonio M; Tavares, Marcos R; Fragoso, Maria C B V; Pereira, Adelaide A; Dahia, Patricia L M; Mulligan, Lois M; Toledo, Sergio P A

2010-03-01

Previous studies have shown that double RET mutations may be associated with unusual multiple endocrine neoplasia type 2 (MEN 2) phenotypes. Our objective was to report the clinical features of patients harboring a previously unreported double mutation of the RET gene and to characterize this mutation in vitro. Sixteen patients from four unrelated families and harboring the C634Y/Y791F double RET germline mutation were included in the study. Large pheochromocytomas measuring 6.0-14 cm and weighing up to 640 g were identified in the four index cases. Three of the four tumors were bilateral. High penetrance of pheochromocytoma was also seen in the C634Y/Y791F-mutation-positive relatives (seven of nine, 77.7%). Of these, two cases had bilateral tumors, one presented with multifocal tumors, two cases had large tumors (>5 cm), and one case, which was diagnosed with a large (5.5 x 4.5 x 4.0 cm) pheochromocytoma, reported early onset of symptoms of the disease (14 yr old). The overall penetrance of pheochromocytoma was 84.6% (11 of 13). Development of medullary thyroid carcinoma in our patients seemed similar to that observed in patients with codon 634 mutations. Haplotype analysis demonstrated that the mutation did not arise from a common ancestor. In vitro studies showed the double C634Y/Y791F RET receptor was significantly more phosphorylated than either activated wild-type receptor or single C634Y and Y791F RET mutants. Our data suggest that the natural history of the novel C634Y/Y791F double mutation carries a codon 634-like pattern of medullary thyroid carcinoma development, is associated with increased susceptibility to unusually large bilateral pheochromocytomas, and is likely more biologically active than each individual mutation.

Ground penetrating radar (GPR) analysis : Phase I.

DOT National Transportation Integrated Search

2009-11-01

"The objective of this work is to evaluate the feasibility of expanding the MDT's Ground Penetrating : Radar (GPR) program to a broader range of pavement evaluation activities. Currently, MDT uses GPR in : conjunction with its Falling Weight Deflecto...

Ground penetrating radar evaluation of new pavement density.

DOT National Transportation Integrated Search

2015-02-01

The objective of this project was to map pavement surface density variations using dielectric : measurements from ground penetrating radar (GPR). The work was carried out as part of an : Asphalt Intelligent Compaction demonstration project on SR 539 ...

Penetrating skull fracture by a wooden object: Management dilemmas and literature review

PubMed Central

Arifin, Muhammad Zafrullah; Gill, Arwinder Singh; Faried, Ahmad

2012-01-01

Most penetrating skull injuries are caused by gun shot wounds or missiles. The compound depressed skull fracture represents an acute neurosurgical emergency. Management and diagnosis of such cases have been described, but its occurence following a fall onto a piece of wood is quite unusual. A 75-year-old female fell onto a piece of wood that penetrated her skull on the left frontal region and was treated in our department. The patient had no neurological deficits during presentation. She was managed surgically and removal of the wooden object was performed to prevent early or late infection complications. Wooden foreign bodies often pose a different set of challenges as far as penetrating injuries to the brain are concerned. Radiological difficulties and increased rates of infection due to its porous nature make these types of injuries particularly interesting. Their early diagnosis and appropriate treatment can minimize the risk of complications. PMID:23293668

Pulsed x-ray imaging of high-density objects using a ten picosecond high-intensity laser driver

NASA Astrophysics Data System (ADS)

Rusby, D. R.; Brenner, C. M.; Armstrong, C.; Wilson, L. A.; Clarke, R.; Alejo, A.; Ahmed, H.; Butler, N. M. H.; Haddock, D.; Higginson, A.; McClymont, A.; Mirfayzi, S. R.; Murphy, C.; Notley, M.; Oliver, P.; Allott, R.; Hernandez-Gomez, C.; Kar, S.; McKenna, P.; Neely, D.

2016-10-01

Point-like sources of X-rays that are pulsed (sub nanosecond), high energy (up to several MeV) and bright are very promising for industrial and security applications where imaging through large and dense objects is required. Highly penetrating X-rays can be produced by electrons that have been accelerated by a high intensity laser pulse incident onto a thin solid target. We have used a pulse length of 10ps to accelerate electrons to create a bright x-ray source. The bremsstrahlung temperature was measured for a laser intensity from 8.5-12×1018 W/cm2. These x-rays have sequentially been used to image high density materials using image plate and a pixelated scintillator system.

Estimating Consequences of MMOD Penetrations on ISS

NASA Technical Reports Server (NTRS)

Evans, H.; Hyde, James; Christiansen, E.; Lear, D.

2017-01-01

The threat from micrometeoroid and orbital debris (MMOD) impacts on space vehicles is often quantified in terms of the probability of no penetration (PNP). However, for large spacecraft, especially those with multiple compartments, a penetration may have a number of possible outcomes. The extent of the damage (diameter of hole, crack length or penetration depth), the location of the damage relative to critical equipment or crew, crew response, and even the time of day of the penetration are among the many factors that can affect the outcome. For the International Space Station (ISS), a Monte-Carlo style software code called Manned Spacecraft Crew Survivability (MSCSurv) is used to predict the probability of several outcomes of an MMOD penetration-broadly classified as loss of crew (LOC), crew evacuation (Evac), loss of escape vehicle (LEV), and nominal end of mission (NEOM). By generating large numbers of MMOD impacts (typically in the billions) and tracking the consequences, MSCSurv allows for the inclusion of a large number of parameters and models as well as enabling the consideration of uncertainties in the models and parameters. MSCSurv builds upon the results from NASA's Bumper software (which provides the probability of penetration and critical input data to MSCSurv) to allow analysts to estimate the probability of LOC, Evac, LEV, and NEOM. This paper briefly describes the overall methodology used by NASA to quantify LOC, Evac, LEV, and NEOM with particular emphasis on describing in broad terms how MSCSurv works and its capabilities and most significant models.

Predicting the Consequences of MMOD Penetrations on the International Space Station

NASA Technical Reports Server (NTRS)

Hyde, James; Christiansen, E.; Lear, D.; Evans

2018-01-01

The threat from micrometeoroid and orbital debris (MMOD) impacts on space vehicles is often quantified in terms of the probability of no penetration (PNP). However, for large spacecraft, especially those with multiple compartments, a penetration may have a number of possible outcomes. The extent of the damage (diameter of hole, crack length or penetration depth), the location of the damage relative to critical equipment or crew, crew response, and even the time of day of the penetration are among the many factors that can affect the outcome. For the International Space Station (ISS), a Monte-Carlo style software code called Manned Spacecraft Crew Survivability (MSCSurv) is used to predict the probability of several outcomes of an MMOD penetration-broadly classified as loss of crew (LOC), crew evacuation (Evac), loss of escape vehicle (LEV), and nominal end of mission (NEOM). By generating large numbers of MMOD impacts (typically in the billions) and tracking the consequences, MSCSurv allows for the inclusion of a large number of parameters and models as well as enabling the consideration of uncertainties in the models and parameters. MSCSurv builds upon the results from NASA's Bumper software (which provides the probability of penetration and critical input data to MSCSurv) to allow analysts to estimate the probability of LOC, Evac, LEV, and NEOM. This paper briefly describes the overall methodology used by NASA to quantify LOC, Evac, LEV, and NEOM with particular emphasis on describing in broad terms how MSCSurv works and its capabilities and most significant models.

Extreme value statistics for two-dimensional convective penetration in a pre-main sequence star

NASA Astrophysics Data System (ADS)

Pratt, J.; Baraffe, I.; Goffrey, T.; Constantino, T.; Viallet, M.; Popov, M. V.; Walder, R.; Folini, D.

2017-08-01

Context. In the interior of stars, a convectively unstable zone typically borders a zone that is stable to convection. Convective motions can penetrate the boundary between these zones, creating a layer characterized by intermittent convective mixing, and gradual erosion of the density and temperature stratification. Aims: We examine a penetration layer formed between a central radiative zone and a large convection zone in the deep interior of a young low-mass star. Using the Multidimensional Stellar Implicit Code (MUSIC) to simulate two-dimensional compressible stellar convection in a spherical geometry over long times, we produce statistics that characterize the extent and impact of convective penetration in this layer. Methods: We apply extreme value theory to the maximal extent of convective penetration at any time. We compare statistical results from simulations which treat non-local convection, throughout a large portion of the stellar radius, with simulations designed to treat local convection in a small region surrounding the penetration layer. For each of these situations, we compare simulations of different resolution, which have different velocity magnitudes. We also compare statistical results between simulations that radiate energy at a constant rate to those that allow energy to radiate from the stellar surface according to the local surface temperature. Results: Based on the frequency and depth of penetrating convective structures, we observe two distinct layers that form between the convection zone and the stable radiative zone. We show that the probability density function of the maximal depth of convective penetration at any time corresponds closely in space with the radial position where internal waves are excited. We find that the maximal penetration depth can be modeled by a Weibull distribution with a small shape parameter. Using these results, and building on established scalings for diffusion enhanced by large-scale convective motions, we propose a new form for the diffusion coefficient that may be used for one-dimensional stellar evolution calculations in the large Péclet number regime. These results should contribute to the 321D link.

Ground penetrating radar (GPR) analysis : Phase II field evaluation.

DOT National Transportation Integrated Search

2011-10-01

"The objective of this work was to evaluate the feasibility and value of expanding the MDT's Ground : Penetrating Radar (GPR) program to pavement design and rehabilitation, and to network level : evaluation. Phase I of this project concluded that in ...

Prediction of electric vehicle penetration.

DOT National Transportation Integrated Search

2017-05-01

The object of this report is to present the current market status of plug-in-electric : vehicles (PEVs) and to predict their future penetration within the world and U.S. : markets. The sales values for 2016 show a strong year of PEV sales both in the...

Is the Sky Really Falling? An Overview of Orbital Debris

NASA Technical Reports Server (NTRS)

Hull, Scott M.

2015-01-01

Orbital debris has been a prominent topic for a while, even before the movie Gravity came out. An anti-satellite test and a collision with an operational satellite both produced large highly-publicized debris clouds within recent years. While large objects like abandoned satellites and rocket bodies may be the most recognizable and identifiable concerns, a majority of the daily threat comes from the much more numerous smaller particles. In fact, small particle penetration continues to rank among the leading risks for manned space missions to the International Space Station and beyond. How much 'stuff' is up there, where did it come from, what harm can it do, and what is being done about it? These questions and more will be discussed.

Energy Storage Requirements for Achieving 50% Penetration of Solar Photovoltaic Energy in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denholm, Paul; Margolis, Robert

2016-09-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generatorsmore » under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.« less

Energy Storage Requirements for Achieving 50% Solar Photovoltaic Energy Penetration in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denholm, Paul; Margolis, Robert

2016-08-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generatorsmore » under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.« less

Time-of-Flight Microwave Camera.

PubMed

Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

2015-10-05

Microwaves can penetrate many obstructions that are opaque at visible wavelengths, however microwave imaging is challenging due to resolution limits associated with relatively small apertures and unrecoverable "stealth" regions due to the specularity of most objects at microwave frequencies. We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points with a data fusion method to reduce stealth regions, and a frequency modulated continuous wave (FMCW) receiver to achieve depth resolution. The camera captures images with a resolution of 1.5 degrees, multispectral images across the X frequency band (8 GHz-12 GHz), and a time resolution of 200 ps (6 cm optical path in free space). Images are taken of objects in free space as well as behind drywall and plywood. This architecture allows "camera-like" behavior from a microwave imaging system and is practical for imaging everyday objects in the microwave spectrum.

Long range surface plasmon resonance with ultra-high penetration depth for self-referenced sensing and ultra-low detection limit using diverging beam approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isaacs, Sivan, E-mail: sivan.isaacs@gmail.com; Abdulhalim, Ibrahim; NEW CREATE Programme, School of Materials Science and Engineering, 1 CREATE Way, Research Wing, #02-06/08, Singapore 138602

2015-05-11

Using an insulator-metal-insulator structure with dielectric having refractive index (RI) larger than the analyte, long range surface plasmon (SP) resonance exhibiting ultra-high penetration depth is demonstrated for sensing applications of large bioentities at wavelengths in the visible range. Based on the diverging beam approach in Kretschmann-Raether configuration, one of the SP resonances is shown to shift in response to changes in the analyte RI while the other is fixed; thus, it can be used as a built in reference. The combination of the high sensitivity, high penetration depth and self-reference using the diverging beam approach in which a dark linemore » is detected of the high sensitivity, high penetration depth, self-reference, and the diverging beam approach in which a dark line is detected using large number of camera pixels with a smart algorithm for sub-pixel resolution, a sensor with ultra-low detection limit is demonstrated suitable for large bioentities.« less

Update of correlations between cone penetration and boring log data : technical summary report.

DOT National Transportation Integrated Search

2009-12-01

The main objective of this project is to update the correlations that are currently used to interpret : Cone Penetration Test (CPT) data for engineering design purposes and to assess the reliability of : using CPT data to predict soil shear strength....

An Experimental Model for Market Penetration.

ERIC Educational Resources Information Center

Caren, William L.

1987-01-01

A plan for college market penetration that has been successful in increasing the applicant pool for one institution is outlined and discussed. It includes development of performance objectives, a schedule, a promotional plan, market survey, and promotional activities including alumni, media, and other community resources. (MSE)

Penetration of the consolidant Paraloid® B-72 in Macuxi indigenous ceramic vessels investigated by neutron tomography

NASA Astrophysics Data System (ADS)

Stanojev Pereira, Marco A.; Pugliesi, Reynaldo

2018-05-01

The neutron tomography technique was applied in studying the penetration of the consolidant Paraloid® B-72 in contemporary indigenous ceramic vessels. The study was carried out for two distinct and controlled air humidity conditions, 40% and 90%, in which the vessels were exposed, before the consolidant application. The obtained images have proved that the penetration of Paraloid® B-72 in the ceramic does not depend on the humidity condition in which it was applied, moreover allowed a macro-visualization of the consolidant penetration in the ceramic vessel. As the vessels used in the present work were manufactured by an indigenous artisan, Macuxi, according to the same procedures and raw materials used by the ancient artisans, the results obtained can be used as a guide to assist experts, both in the study of archeological objects of Macuxi origin, as well as other objects that had been made by other tribes that lived in the same Amazon region, in Brazil.

Safety, tolerability, and cerebrospinal fluid penetration of ursodeoxycholic Acid in patients with amyotrophic lateral sclerosis.

PubMed

Parry, Gareth J; Rodrigues, Cecilia M P; Aranha, Marcia M; Hilbert, Sarah J; Davey, Cynthia; Kelkar, Praful; Low, Walter C; Steer, Clifford J

2010-01-01

Amyotrophic lateral sclerosis is a progressive degenerative disease, which typically leads to death in 3 to 5 years. Neuronal cell death offers a potential target for therapeutic intervention. Ursodeoxycholic acid is a cytoprotective, endogenous bile acid that has been shown to be neuroprotective in experimental Huntington and Alzheimer diseases, retinal degeneration, and ischemic and hemorrhagic stroke. The objective of this research was to study the safety and the tolerability of ursodeoxycholic acid in amyotrophic lateral sclerosis and document effective and dose-dependent cerebrospinal fluid penetration. Eighteen patients were randomly assigned to receive ursodeoxycholic acid at doses of 15, 30, and 50 mg/kg of body weight per day. Serum and cerebrospinal fluid were obtained for analysis after 4 weeks of treatment. Treatment-emergent clinical and laboratory events were monitored weekly. Our data indicated that ursodeoxycholic acid is well tolerated by all subjects at all doses. We also showed that ursodeoxycholic acid is well absorbed after oral administration and crosses the blood-brain barrier in a dose-dependent manner. These results show excellent safety and tolerability of ursodeoxycholic acid. The drug penetrates the cerebrospinal fluid in a dose-dependent manner. A large, placebo-controlled clinical trial is needed to assess the efficacy of ursodeoxycholic acid in treating amyotrophic lateral sclerosis.

OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS & HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alan Black; Arnis Judzis

2004-10-01

The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit-fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all major preparations for themore » high pressure drilling campaign. Baker Hughes encountered difficulties in providing additional pumping capacity before TerraTek's scheduled relocation to another facility, thus the program was delayed further to accommodate the full testing program.« less

Age-associated impact on presentation and outcome for penetrating thoracic trauma in the adult and pediatric patient populations.

PubMed

Mollberg, Nathan M; Tabachnick, Deborah; Lin, Fang-Ju; Merlotti, Gary J; Varghese, Thomas K; Arensman, Robert M; Massad, Malek G

2014-02-01

Studies reporting on penetrating thoracic trauma in the pediatric population have been limited by small numbers and implied differences with the adult population. Our objectives were to report on a large cohort of pediatric patients presenting with penetrating thoracic trauma and to determine age-related impacts on management and outcome through comparison with an adult cohort. A Level I trauma center registry was queried between 2006 and 2012. All patients presenting with penetrating thoracic trauma were identified. Patient demographics, injury mechanism, injury severity, admission physiology, and outcome were recorded. Patients were compared, and outcomes were analyzed based on age at presentation, with patients 17 years or younger defining our pediatric cohort. A total of 1,423 patients with penetrating thoracic trauma were admitted during the study period. Two hundred twenty patients (15.5%) were pediatric, with 205 being adolescents (13-17 years) and 15 being children (≤ 12 years). In terms of management for the pediatric population, tube thoracostomy alone was needed in 32.7% (72 of 220), whereas operative thoracic exploration was performed in 20.0% (44 of 220). Overall mortality was 13.6% (30 of 220). There was no significant difference between the pediatric and adult population with regard to injury mechanism or severity, need for therapeutic intervention, operative approach, use of emergency department thoracotomy, or outcome. Stepwise logistic regression failed to identify age as a predictor for the need for either therapeutic intervention or mortality between the two age groups as a whole. However, subgroup analysis revealed that being 12 years or younger (odds ratio, 3.84; 95% confidence interval, 1.29-11.4) was an independent predictor of mortality. Management of traumatic penetrating thoracic injuries in terms of the need for therapeutic intervention and operative approach was similar between the adult and pediatric populations. Mortality from penetrating thoracic trauma can be predicted based on injury severity, the use of emergency department thoracotomy, and admission physiology for adolescents and adults. Children may be at increased risk for poor outcome independent of injury severity. Epidemiologic study, level III.

USDC based rapid penetrator of packed soil

NASA Technical Reports Server (NTRS)

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Badescu, Mircea

2006-01-01

Environment protection requires more testing and analysis tools. To detect buried chemical containers or other objects embedded in soil and avoid possible damages of them, a penetrator of packed soil operated using low pushing force was developed. The design was based on a novel driving mechanism of the ultrasonic/sonic driller/corer (USDC) device developed in the NDEAA lab at JPL [Bar-Cohen et al 2001, Bao et al 2003]. In the penetrator, a small free-flying mass is energized by a piezoelectric transducer and impacts a rod probe on its shoulder at frequencies of hundreds times per second. The impacts help the probe to penetrate the packed soil rapidly. A great reduction of the needed pushing force for penetration was achieved. The details of the design of the prototype penetrator and the results of performance tests are presented.

Confocal Raman microspectrometry: a vectorial electromagnetic treatment of the light focused and collected through a planar interface and its application to the study of a thin coating.

PubMed

Sourisseau, C; Maraval, P

2003-11-01

In-depth confocal Raman microspectrometry (CRM) studies through a planar interface between materials of mismatched refraction indices are known to be affected by a decrease of both the collected Raman intensity and the axial resolution as a function of the penetration depth. Following a previous model, which takes the refraction, diffraction, and spherical aberration effects into account when focusing a Gaussian incident laser beam with a high numerical aperture objective lens, a complete vectorial treatment of these phenomena is considered. It is demonstrated that off-axis refraction effects cannot be neglected and that the dimension of the confocal pinhole aperture plays a crucial role on the effective focal plane position and on the collection efficiency. We thus propose a more rigorous and complete approach to the problem, and we find a very good agreement between experimental and theoretical Raman intensity variations for a thick polyethylene sample as a function of the penetration depth. As compared with calculations where only refraction was considered, we confirm that the lengthening of the focus even for a large penetration depth is significantly reduced upon diffraction effects. As an illustrative example, the theoretical Raman responses for a thin coating of approximately 20 microns on a polymer substrate were investigated and compared to experimental results already published. Even though the interfacial region is spread over approximately 5-6 microns when using a 100x objective and a confocal pinhole of 200 microns diameter, it is definitively concluded that the apparent axial resolution is not drastically deteriorated with increasing depth and that the coating thickness may be directly estimated with a precision of approximately 1.0 micron (5%).

Oligoalanine helical callipers for cell penetration.

PubMed

Pazo, Marta; Juanes, Marisa; Lostalé-Seijo, Irene; Montenegro, Javier

2018-06-04

Even for short peptides that are enriched in basic amino acids, the large chemical space that can be spanned by combinations of natural amino acids hinders the rational design of cell penetrating peptides. We here report on short oligoalanine scaffolds for the fine-tuning of peptide helicity in different media and the study of cell penetrating properties. This strategy allowed the extraction of the structure/activity features required for maximal membrane interaction and cellular penetration at minimal toxicity. These results confirmed oligoalanine helical callipers as optimal scaffolds for the rational design and the identification of cell penetrating peptides.

Magnetic field penetration in niobium- and vanadium-based Josephson junctions

NASA Astrophysics Data System (ADS)

Cucolo, A. M.; Pace, S.; Vaglio, R.; di Chiara, A.; Peluso, G.; Russo, M.

1983-02-01

Measurements on the temperature dependence of the magnetic field penetration in Nb-NbxOy-Pb and V-VxOy-Pb Josephson junctions have been performed. Results on the zero-temperature penetration depth in niobium films are far above the bulk values although consistent with other measurements on junctions reported in the literature. For vanadium junctions anomalously large penetration depth values are obtained at low temperatures. Nevertheless, the temperature dependence is in reasonable agreement with the local dirty limit model.

Field evaluation of viscosity and penetration-graded asphalt cements : asphalt cement consistency study : final report.

DOT National Transportation Integrated Search

1977-04-01

The major objectives of this study were three-fold and can be listed as follows in their order of importance: : (1) To seek data relative to the changes that occur with time in the physical characteristics of penetration and viscosity graded-asphalt ...

Effect of moisture content and dry unit weight on the resilient modulus of subgrade soils predicted by cone penetration test.

DOT National Transportation Integrated Search

2002-06-01

The objective of this study was to investigate the effect of moisture content and dry unit weight on the resilient characteristics of subgrade soil predicted by the cone penetration test. An experimental program was conducted in which cone penetratio...

Dynamic cone penetration tests in granular media: Determination of the tip's dynamic load-penetration curve

NASA Astrophysics Data System (ADS)

Escobar, E.; Benz, M.; Gourvès, R.; Breul, P.

2013-06-01

In this article a two-dimensional discrete numerical model, realized in PFC2D, is presented. This model is used in the dynamic penetration tests in a granular medium. Its objective being the validation of the measurement technique offered by Panda 3® (Benz et al. 2011) which is designed to calculate the tip's load-penetration curve for each impact in the soil where different parameters are used. To do so, we have compared the results obtained by calculation during the impacts to those measured directly in the model of a penetrometer through the installation of the gauges at the cone.

A Cost-effective Satellite-aircraft-drogue Approach for Studying Estuarine Circulation and Shelf Waste Dispersion. [Delaware Bay

NASA Technical Reports Server (NTRS)

Klemas, V. (Principal Investigator); Davis, G.; Wang, H.; Whelan, W.; Tornatore, G.

1975-01-01

The author has identified the following significant results. Satellites, such as ERTS-1, can be used to obtain a synoptic view of current circulation over large coastal areas. Since in turbid coastal regions suspended sediment acts as a natural tracer, cost is minimized by eliminating the need for expensive injections of large volumes of dye such as Rhodamine-B. One of the principal shortcomings of satellite imaging of coastal currents was its inability to determine current magnitude and to penetrate beyond the upper few meters of the water column. These objections were overcome by complementing satellite observations with drogues tracking currents at various selected depths. By combining the satellite's wide coverage with aircraft or shore stations capable of tracking expendable drogues, a cost effective, integrated system was devised for monitoring currents over large areas, various depths, and under severe environmental conditions.

NDE of PWA 1480 single crystal turbine blade material

NASA Technical Reports Server (NTRS)

Klima, Stanley J.; Orange, Thomas W.; Dreshfield, Robert L.

1993-01-01

Cantilever bending fatigue specimens were examined by fluorescent liquid penetrant and radioactive gas penetrant (Krypton) non-destructive evaluation (NDE) methods and tested. Specimens with cast, ground, or polished surface were evaluated to study the effect of surface condition on NDE and fatigue crack initiation. Fractographic and metallurgical analyses were performed to determine the nature of crack precursors. Preliminary results show that fatigue strength was lower for specimens with cast surfaces than for specimens with machined surfaces. The liquid penetrant and gas penetrant techniques both provided indications of a large population of defects on the cast surfaces. On ground or polished specimen surfaces, the gas penetrant appeared to estimate the actual number of voids more accurately than the liquid penetrant.

A Close Cut: A Technical Report of Endovascular Removal of a Penetrating Intravascular Foreign Body after a Lawn Mowing Injury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tapping, C. R.; Gallo, A.; Silva, R. J. De

2012-12-15

We present a case of endovascular retrieval of a penetrating foreign body that was originally lodged in the mediastinum and then migrated to the hepatic vein. The steel nail entered the thorax and traversed the left lung causing a pneumothorax. The patient underwent a thoracotomy, but the foreign body had migrated from its original mediastinal position. A postsurgical CT showed that the object was below the right hemidiaphragm. Diagnostic venogram demonstrated that the object was in the main hepatic vein. Using a double-snare technique, the object was safely and successfully removed from the hepatic vein via the right common femoralmore » vein.« less

Impact of simulated climate and building features on the penetration of toxic gases from the ambient into the indoor environment

EPA Science Inventory

This research is a combination of experimental results and analysis of formaldehyde penetration across a residential building envelope with the objective of developing an understanding of the factors that govern indoor air concentrations of air toxics and to provide linkages betw...

Drilled Shaft Foundations for Noise Barrier Walls and Slope Stabilization

DOT National Transportation Integrated Search

2002-12-01

This research project is focused on two primary objectives. The first objective relates to the development of a methodology for using the SPT (Standard Penetration Test) results to design the laterally loaded drilled shafts. The second objective aims...

The merger of small and large black holes

NASA Astrophysics Data System (ADS)

Mösta, P.; Andersson, L.; Metzger, J.; Szilágyi, B.; Winicour, J.

2015-12-01

We present simulations of binary black-hole mergers in which, after the common outer horizon has formed, the marginally outer trapped surfaces (MOTSs) corresponding to the individual black holes continue to approach and eventually penetrate each other. This has very interesting consequences according to recent results in the theory of MOTSs. Uniqueness and stability theorems imply that two MOTSs which touch with a common outer normal must be identical. This suggests a possible dramatic consequence of the collision between a small and large black hole. If the penetration were to continue to completion, then the two MOTSs would have to coalesce, by some combination of the small one growing and the big one shrinking. Here we explore the relationship between theory and numerical simulations, in which a small black hole has halfway penetrated a large one.

Measured responses of internal enclosures and cables due to burnthrough penetration of weapon cases by lightning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schnetzer, G.H.; Fisher, R.J.; Dinallo, M.A.

1994-08-01

The electrical effects of lightning penetration of the outer case of a weapon on internal structures, such as a firing set housing, and on samples of a flat, flexline detonator cable have been investigated experimentally. Maximum open-circuit voltages measured on either simulated structures (126 V) or the cable (46 V) located directly behind the point of penetration were well below any level that is foreseen to create a threat to nuclear safety. On the other hand, it was found that once full burnthrough of the barrier occurred, significant fractions of the incident continuing currents coupled to both the simulated internalmore » structure (up to 300 A) or to the cable sample (69 A) when each was electrically connected internally to case ground. No occurrence was observed of the injection of large amplitude currents from return strokes occurring after barrier penetration. Under circumstances in which small volumes of trapped gases exist behind penetration sites, rapid heating of the gas by return strokes occurring after burnthrough has been shown to produced large mechanical impulses to the adjacent surfaces.« less

[Comments on the paper by D. Tausch et al. Experiments on the penetration power of various bullets into skin and muscle tissue (author's transl)].

PubMed

Dammermann, W

1979-07-17

The objections in the following comments on a recent paper by Tausch et al. (1978) are raised principally to the points that the mass of the projectile is given an importance for the penetration which is not justified, and that the inherent uncertainty of the measurement data and the scope of validity of the empirical formulas are not sufficiently taken into account. The discussion on the process of penetration and a discontinuity of the depth of penetration as a function of the velocity of the bullet is of fundamental significance, with consequences for the definition of the critical velocity.

Multispectral THz-VIS passive imaging system for hidden threats visualization

NASA Astrophysics Data System (ADS)

Kowalski, Marcin; Palka, Norbert; Szustakowski, Mieczyslaw

2013-10-01

Terahertz imaging, is the latest entry into the crowded field of imaging technologies. Many applications are emerging for the relatively new technology. THz radiation penetrates deep into nonpolar and nonmetallic materials such as paper, plastic, clothes, wood, and ceramics that are usually opaque at optical wavelengths. The T-rays have large potential in the field of hidden objects detection because it is not harmful to humans. The main difficulty in the THz imaging systems is low image quality thus it is justified to combine THz images with the high-resolution images from a visible camera. An imaging system is usually composed of various subsystems. Many of the imaging systems use imaging devices working in various spectral ranges. Our goal is to build a system harmless to humans for screening and detection of hidden objects using a THz and VIS cameras.

Drilled Shaft Foundations for Noise Barrier Walls and Slope Stabilization : Executive Summary

DOT National Transportation Integrated Search

2002-12-01

This research project is focused on two primary objectives. The first objective relates to the development of a methodology for using the SPT (Standard Penetration Test) results to design the laterally loaded drilled shafts. The second objective aims...

A Large and Intact Viral Particle Penetrates the Endoplasmic Reticulum Membrane to Reach the Cytosol

PubMed Central

Inoue, Takamasa; Tsai, Billy

2011-01-01

Non-enveloped viruses penetrate host membranes to infect cells. A cell-based assay was used to probe the endoplasmic reticulum (ER)-to-cytosol membrane transport of the non-enveloped SV40. We found that, upon ER arrival, SV40 is released into the lumen and undergoes sequential disulfide bond disruptions to reach the cytosol. However, despite these ER-dependent conformational changes, SV40 crosses the ER membrane as a large and intact particle consisting of the VP1 coat, the internal components VP2, VP3, and the genome. This large particle subsequently disassembles in the cytosol. Mutant virus and inhibitor studies demonstrate VP3 and likely the viral genome, as well as cellular proteasome, control ER-to-cytosol transport. Our results identify the sequence of events, as well as virus and host components, that regulate ER membrane penetration. They also suggest that the ER membrane supports passage of a large particle, potentially through either a sizeable protein-conducting channel or the lipid bilayer. PMID:21589906

Chronic Disease Prevalence and Medicare Advantage Market Penetration: Findings From the Medical Expenditure Panel Survey.

PubMed

Howard, Steven W; Bernell, Stephanie Lazarus; Casim, Faizan M; Wilmott, Jennifer; Pearson, Lindsey; Byler, Caitlin M; Zhang, Zidong

2015-01-01

By March 2015, 30% of all Medicare beneficiaries were enrolled in Medicare Advantage (MA) plans. Research to date has not explored the impacts of MA market penetration on individual or population health outcomes. The primary objective of this study is to examine the relationships between MA market penetration and the beneficiary's portfolio of cardiometabolic diagnoses. This study uses 2004 to 2008 Medical Expenditure Panel Survey (MEPS) Household Component data to construct an aggregate index that captures multiple diagnoses in one outcome measure (Chronic Disease Severity Index [CDSI]). The MEPS data for 8089 Medicare beneficiaries are merged with MA market penetration data from Centers for Medicare and Medicaid Services (CMS). Ordinary least squares regressions are run with SAS 9.3 to model the effects of MA market penetration on CDSI. The results suggest that each percentage increase in MA market penetration is associated with a greater than 2-point decline in CDSI (lower burden of cardiometabolic chronic disease). Spill-over effects may be driving improvements in the cardiometabolic health of beneficiary populations in counties with elevated levels of MA market penetration.

Chronic Disease Prevalence and Medicare Advantage Market Penetration

PubMed Central

Bernell, Stephanie Lazarus; Casim, Faizan M.; Wilmott, Jennifer; Pearson, Lindsey; Byler, Caitlin M.; Zhang, Zidong

2015-01-01

By March 2015, 30% of all Medicare beneficiaries were enrolled in Medicare Advantage (MA) plans. Research to date has not explored the impacts of MA market penetration on individual or population health outcomes. The primary objective of this study is to examine the relationships between MA market penetration and the beneficiary’s portfolio of cardiometabolic diagnoses. This study uses 2004 to 2008 Medical Expenditure Panel Survey (MEPS) Household Component data to construct an aggregate index that captures multiple diagnoses in one outcome measure (Chronic Disease Severity Index [CDSI]). The MEPS data for 8089 Medicare beneficiaries are merged with MA market penetration data from Centers for Medicare and Medicaid Services (CMS). Ordinary least squares regressions are run with SAS 9.3 to model the effects of MA market penetration on CDSI. The results suggest that each percentage increase in MA market penetration is associated with a greater than 2-point decline in CDSI (lower burden of cardiometabolic chronic disease). Spill-over effects may be driving improvements in the cardiometabolic health of beneficiary populations in counties with elevated levels of MA market penetration. PMID:28462266

Ground penetrating radar (GPR) detects fine roots of agricultural crops in the field

Treesearch

Xiuwei Liu; Xuejun Dong; Qingwu Xue; Daniel I. Leskovar; John Jifon; John R. Butnor; Thomas Marek

2018-01-01

Aim Ground penetrating radar (GPR) as a non-invasive technique is widely used in coarse root detection. However, the applicability of the technique to detect fine roots of agricultural crops is unknown. The objective of this study was to assess the feasibility of utilizing GPR to detect fine roots in the field.

Is skin penetration a determining factor in skin sensitization potential and potency? Refuting the notion of a LogKow threshold for Skin Sensitization

EPA Science Inventory

Summary:Background. It is widely accepted that substances that cannot penetrate through the skin will not be sensitisers. Thresholds based on relevant physicochemical parameters such as a LogKow > 1 and a MW < 500, are assumed and widely accepted as self-evident truths. Objective...

Time-of-Flight Microwave Camera

PubMed Central

Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

2015-01-01

Microwaves can penetrate many obstructions that are opaque at visible wavelengths, however microwave imaging is challenging due to resolution limits associated with relatively small apertures and unrecoverable “stealth” regions due to the specularity of most objects at microwave frequencies. We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points with a data fusion method to reduce stealth regions, and a frequency modulated continuous wave (FMCW) receiver to achieve depth resolution. The camera captures images with a resolution of 1.5 degrees, multispectral images across the X frequency band (8 GHz–12 GHz), and a time resolution of 200 ps (6 cm optical path in free space). Images are taken of objects in free space as well as behind drywall and plywood. This architecture allows “camera-like” behavior from a microwave imaging system and is practical for imaging everyday objects in the microwave spectrum. PMID:26434598

Some topics in the magnetohydrodynamics of accreting magnetic compact objects

NASA Technical Reports Server (NTRS)

Aly, J. J.

1986-01-01

Magnetic compact objects (neutron stars or white dwarfs) are currently thought to be present in many accreting systems that are releasing large amounts of energy. The magnetic field of the compact star may interact strongly with the accretion flow and play an essential role in the physics of these systems. Some magnetohydrodynamic (MHD) problems that are likely to be relevant in building up self-consistent models of the interaction between the accreting plasma and the star's magnetosphere are addressed in this series of lectures. The basic principles of MHD are first introduced and some important MHD mechanisms (Rayleigh-Taylor and Kelvin-Helmholtz instabilities; reconnection) are discussed, with particular reference to their role in allowing the infalling matter to penetrate the magnetosphere and mix with the field. The structure of a force-free magnetosphere and the possibility of quasistatic momentum and energy transfer between regions linked by field-aligned currents are then studied in some detail. Finally, the structure of axisymmetric accretion flows onto magnetic compact objects is considered.

Feasibility study for near-earth-object tracking by a piggybacked micro-satellite with penetrators

NASA Astrophysics Data System (ADS)

Weiss, P.; Leung, W.; Yung, K. L.

2010-05-01

As of August 2007, over 5000 near-earth-objects (NEO) have been discovered. Some already represent a potential danger to the Earth while others might become hazards in the future. The Planetary Society organised in 2007 the "Apophis Mission Design Competition" in response to this potential threat with the objective to identify promising concepts to track NEOs; the asteroid 99942 Apophis was taken as the study case. This paper describes the "Houyi" proposal which was evaluated by the competition jury as an innovative approach to this problem. Instead of launching a large satellite for NEO tracking, this novel concept proposes a miniaturized satellite that is piggybacked onto a larger (scientific) mission. Such mission design would drastically reduce the costs for NEO surveillance. The presented scenario uses the ESA's SOLO mission as a design baseline for the piggyback option. This paper summarizes the architecture of this CubeSat towards Apophis and extends the previous study by focusing on the feasibility of a piggybacked mission in terms of propulsion requirements.

Time-of-Flight Microwave Camera

NASA Astrophysics Data System (ADS)

Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

2015-10-01

Microwaves can penetrate many obstructions that are opaque at visible wavelengths, however microwave imaging is challenging due to resolution limits associated with relatively small apertures and unrecoverable “stealth” regions due to the specularity of most objects at microwave frequencies. We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points with a data fusion method to reduce stealth regions, and a frequency modulated continuous wave (FMCW) receiver to achieve depth resolution. The camera captures images with a resolution of 1.5 degrees, multispectral images across the X frequency band (8 GHz-12 GHz), and a time resolution of 200 ps (6 cm optical path in free space). Images are taken of objects in free space as well as behind drywall and plywood. This architecture allows “camera-like” behavior from a microwave imaging system and is practical for imaging everyday objects in the microwave spectrum.

Measurement of in-situ strength using projectile penetration: Tests of a new launching system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hearst, J.R.; Newmark, R.L.; Charest, J.A.

1987-10-01

The Lawrence Livermore National Laboratory has a continuing need to measure rock strength in situ, both for simple prediction of cavity size, and as input to computational models. In a previous report we compared two methods for measuring formation strength in situ: projectile penetration and a cone penetrometer. We determined that the projectile method was more promising for application to our large-diameter (2-4-m) hole environment. A major practical problem has been the development of a launcher and an apparatus for measuring depth of penetration that would be suitable for use in large-diameter holes. We are developing a gas-gun launcher systemmore » that will be capable of measuring both depth of penetration and deceleration of a reusable projectile. The current version of the launcher is trailer-mounted for testing at our Nevada Test Site (NTS) in tunnels and outcrops, but its design is such that it can be readily adapted for emplacement hole use. We test the current launcher on 60-cm cubes of gypsum cement, mixed to provie a range of densities (1.64 to 2.0 g/cc) and strengths (3 to 17 MPa). We compared depth of penetration of a 84-g projectile from a ''Betsy'' seismic gun - traveling on the order of 500 m/s - with the depth of penetration of a 13-kg projectile from the gas gun - traveling on the order of 30 m/s. For projectiles with the same nose size and shape, impacting targets of approximately constant strength, penetration depth was proportional to projectile kinetic energy. The ratio of kinetic energy to penetration depth was approximately proportional to target strength. Tests in tuffs with a wide range of strengths at NTS gave a similar linear relationship between the ratio of kinetic energy to penetration and target strength, and also a linear relationship between deceleration and strength. It appears that penetration can indeed be used as a semiquantitative measure of strength.« less

Hole 504B reclaimed for future drilling

NASA Astrophysics Data System (ADS)

Leg 137 Scientific Drilling Party

Hole 504B, perhaps the most important in situ reference section for the structure and composition of the oceanic crust, has been reopened for future drilling and downhole measurements after remedial operations during Leg 137 of the Ocean Drilling Program. By far the deepest penetration into oceanic crust, Hole 504B had been feared lost when a large diamond bit and assorted hardware (“junk”) broke off in the bottom of the hole at the end of ODP Leg 111 in 1986. Since then ODP's drill ship, JOIDES Resolution, has circumnavigated the globe, with no opportunity to redress this situation. But the objective of deep penetration into the oceanic crust and the hole itself are considered so important by marine Earth scientists that remedial measures in Hole 504B were undertaken as soon as the drill ship returned to the eastern Pacific. These measures succeeded better than had been hoped. Hole 504B was reopened after less than a week of cleaning operations, which included grappling for the lost junk with tools to pull it from the hole (called “fishing”) and grinding or milling the junk away.

Compound antimalarial ethosomal cataplasm: preparation, evaluation, and mechanism of penetration enhancement

PubMed Central

Shen, Shuo; Liu, Shu-Zhi; Zhang, Yu-Shi; Du, Mao-Bo; Liang, Ai-Hua; Song, Li-Hua; Ye, Zu-Guang

2015-01-01

Malaria is still a serious public health problem in some parts of the world. The problems of recurrence and drug resistance are increasingly more serious. Thus, it is necessary to develop a novel antimalarial agent. The objectives of this study were to construct a novel compound antimalarial transdermal nanosystem–ethosomal cataplasm, to investigate its characteristics and efficiency, and to systematically explore the penetration-enhancing mechanisms of ethosomal cataplasm. Artesunate-loaded ethosomes and febrifugine-loaded ethosomes were prepared, and their characteristics were evaluated. Drug-loaded ethosomes were incorporated in the matrix of cataplasm to form the compound antimalarial ethosomal cataplasm. With the help of ethosomal technology, the accumulated permeation quantity of artesunate significantly increased at 8 hours after administration, which was 1.57 times as much as that of conventional cataplasm. Soon after administration, the ethosomal cataplasm could make a large quantity of antimalarial drug quickly penetrate through skin, then the remaining drug in the ethosomal cataplasm could be steadily released. These characteristics of ethosomal cataplasm are favorable for antimalarial drugs to kill Plasmodium spp. quickly and prevent the resurgence of Plasmodium spp. As expected, the ethosomal cataplasm showed good antimalarial efficiency in this experiment. The negative conversion rates were 100% and the recurrence rates were 0% at all dosages. The mechanism of penetration enhancement of the ethosomal cataplasm was systematically explored using an optics microscope, polarization microscope, and transmission electron microscopy. The microstructure, ultrastructure, and birefringent structure in skin were observed. Data obtained in this study showed that the application of ethosomal technology to antimalarial cataplasm could improve the transdermal delivery of drug, enhance the efficacy, and facilitate practical application in clinic. PMID:26170661

Aerosol sampling system for collection of Capstone depleted uranium particles in a high-energy environment.

PubMed

Holmes, Thomas D; Guilmette, Raymond A; Cheng, Yung Sung; Parkhurst, Mary Ann; Hoover, Mark D

2009-03-01

The Capstone Depleted Uranium (DU) Aerosol Study was undertaken to obtain aerosol samples resulting from a large-caliber DU penetrator striking an Abrams or Bradley test vehicle. The sampling strategy was designed to (1) optimize the performance of the samplers and maintain their integrity in the extreme environment created during perforation of an armored vehicle by a DU penetrator, (2) collect aerosols as a function of time post perforation, and (3) obtain size-classified samples for analysis of chemical composition, particle morphology, and solubility in lung fluid. This paper describes the experimental setup and sampling methodologies used to achieve these objectives. Custom-designed arrays of sampling heads were secured to the inside of the target in locations approximating the breathing zones of the crew locations in the test vehicles. Each array was designed to support nine filter cassettes and nine cascade impactors mounted with quick-disconnect fittings. Shielding and sampler placement strategies were used to minimize sampler loss caused by the penetrator impact and the resulting fragments of eroded penetrator and perforated armor. A cyclone train was used to collect larger quantities of DU aerosol for measurement of chemical composition and solubility. A moving filter sample was used to obtain semicontinuous samples for DU concentration determination. Control for the air samplers was provided by five remotely located valve control and pressure monitoring units located inside and around the test vehicle. These units were connected to a computer interface chassis and controlled using a customized LabVIEW engineering computer control program. The aerosol sampling arrays and control systems for the Capstone study provided the needed aerosol samples for physicochemical analysis, and the resultant data were used for risk assessment of exposure to DU aerosol.

Aerosol Sampling System for Collection of Capstone Depleted Uranium Particles in a High-Energy Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holmes, Thomas D.; Guilmette, Raymond A.; Cheng, Yung-Sung

2009-03-01

The Capstone Depleted Uranium Aerosol Study was undertaken to obtain aerosol samples resulting from a kinetic-energy cartridge with a large-caliber depleted uranium (DU) penetrator striking an Abrams or Bradley test vehicle. The sampling strategy was designed to (1) optimize the performance of the samplers and maintain their integrity in the extreme environment created during perforation of an armored vehicle by a DU penetrator, (2) collect aerosols as a function of time post-impact, and (3) obtain size-classified samples for analysis of chemical composition, particle morphology, and solubility in lung fluid. This paper describes the experimental setup and sampling methodologies used tomore » achieve these objectives. Custom-designed arrays of sampling heads were secured to the inside of the target in locations approximating the breathing zones of the vehicle commander, loader, gunner, and driver. Each array was designed to support nine filter cassettes and nine cascade impactors mounted with quick-disconnect fittings. Shielding and sampler placement strategies were used to minimize sampler loss caused by the penetrator impact and the resulting fragments of eroded penetrator and perforated armor. A cyclone train was used to collect larger quantities of DU aerosol for chemical composition and solubility. A moving filter sample was used to obtain semicontinuous samples for depleted uranium concentration determination. Control for the air samplers was provided by five remotely located valve control and pressure monitoring units located inside and around the test vehicle. These units were connected to a computer interface chassis and controlled using a customized LabVIEW engineering computer control program. The aerosol sampling arrays and control systems for the Capstone study provided the needed aerosol samples for physicochemical analysis, and the resultant data were used for risk assessment of exposure to DU aerosol.« less

Compound antimalarial ethosomal cataplasm: preparation, evaluation, and mechanism of penetration enhancement.

PubMed

Shen, Shuo; Liu, Shu-Zhi; Zhang, Yu-Shi; Du, Mao-Bo; Liang, Ai-Hua; Song, Li-Hua; Ye, Zu-Guang

2015-01-01

Malaria is still a serious public health problem in some parts of the world. The problems of recurrence and drug resistance are increasingly more serious. Thus, it is necessary to develop a novel antimalarial agent. The objectives of this study were to construct a novel compound antimalarial transdermal nanosystem-ethosomal cataplasm, to investigate its characteristics and efficiency, and to systematically explore the penetration-enhancing mechanisms of ethosomal cataplasm. Artesunate-loaded ethosomes and febrifugine-loaded ethosomes were prepared, and their characteristics were evaluated. Drug-loaded ethosomes were incorporated in the matrix of cataplasm to form the compound antimalarial ethosomal cataplasm. With the help of ethosomal technology, the accumulated permeation quantity of artesunate significantly increased at 8 hours after administration, which was 1.57 times as much as that of conventional cataplasm. Soon after administration, the ethosomal cataplasm could make a large quantity of antimalarial drug quickly penetrate through skin, then the remaining drug in the ethosomal cataplasm could be steadily released. These characteristics of ethosomal cataplasm are favorable for antimalarial drugs to kill Plasmodium spp. quickly and prevent the resurgence of Plasmodium spp. As expected, the ethosomal cataplasm showed good antimalarial efficiency in this experiment. The negative conversion rates were 100% and the recurrence rates were 0% at all dosages. The mechanism of penetration enhancement of the ethosomal cataplasm was systematically explored using an optics microscope, polarization microscope, and transmission electron microscopy. The microstructure, ultrastructure, and birefringent structure in skin were observed. Data obtained in this study showed that the application of ethosomal technology to antimalarial cataplasm could improve the transdermal delivery of drug, enhance the efficacy, and facilitate practical application in clinic.

Regional associations between Medicare Advantage penetration and administrative claims-based measures of hospital outcome

PubMed Central

Kulkarni, Vivek T.; Shah, Sachin J.; Bernheim, Susannah M.; Wang, Yongfei; Normand, Sharon-Lise T.; Han, Lein F.; Rapp, Michael T.; Drye, Elizabeth E.; Krumholz, Harlan M.

2017-01-01

Structured Abstract Background Risk-standardized measures of hospital outcomes reported by the Centers for Medicare and Medicaid Services (CMS) include Medicare fee-for-service (FFS) patients and exclude Medicare Advantage (MA) patients due to data availability. MA penetration varies greatly nationwide and appears associated with increased FFS population risk. Whether variation in MA penetration affects the performance on the CMS measures is unknown. Objective To determine whether the MA penetration rate is associated with outcomes measures based on fee-for-service patients. Research Design In this retrospective study, 2008 MA penetration was estimated at the Hospital Referral Region (HRR) level. Risk-standardized mortality rates (RSMRs), and risk-standardized readmission rates (RSRRs) for heart failure, acute myocardial infarction, and pneumonia from 2006–2008 were estimated among HRRs, along with several markers of FFS population risk. Weighted linear regression was used to test the association between each of these variables and MA penetration among HRRs. Results Among 304 HRRs, MA penetration varied greatly (median: 17.0%, range: 2.1% – 56.6%). Although MA penetration was significantly (p<0.05) associated with 5 of the 6 markers of FFS population risk, MA penetration was insignificantly (p≥0.05) associated with 5 of 6 hospital outcome measures. Conclusion RSMRs and RSRRs for heart failure, acute myocardial infarction, and pneumonia do not seem to differ systematically with MA penetration, lending support to the widespread use of these measures even in areas of high MA penetration. PMID:22456113

Planetary and Primitive Object Strength Measurements and Sampling Apparatus

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.

1997-01-01

We present experimental data and a model for the low-velocity (subsonic, 0 - 1000 m/s) penetration of brittle materials by both solid and hollow (i.e., coring) penetrators. The experiments show that penetration is proportional to momentum/frontal area of the penetrator. Because of the buildup of a cap in front of blunt penetrators, the presence or absence of a streamlined or sharp front end usually has a negligible effect for impact into targets with strength. The model accurately predicts the dependence of penetration depth on the various parameters of the target-penetrator system, as well as the qualitative condition of the target material ingested by a corer. In particular, penetration depth is approximately inversely proportional to the static bearing strength of the target. The bulk density of the target material has only a small effect on penetration, whereas friction can be significant, especially at higher impact velocities, for consolidated materials. This trend is reversed for impacts into unconsolidated materials. The present results suggest that the depth of penetration is a good measure of the strength, but not the density, of a consolidated target. Both experiments and model results show that, if passage through the mouth of a coring penetrator requires initially porous target material to be compressed to less than 26% porosity, the sample collected by the corer will be highly fragmented. If the final porosity remains above 26%, then most materials, except cohesionless materials, such as dry sand, will be collected as a compressed slug of material.

The effects of HMO ownership on hospital costs and revenues: is there a difference between for-profit and nonprofit plans?

PubMed

Shen, Yu-Chu; Melnick, Glenn

2004-01-01

We conducted multivariate analyses to examine whether high health maintenance organization (HMO) penetration and large share of for-profit health plans in a market reduced hospital cost and revenue growth rates between 1989 and 1998. We found that hospitals in high HMO areas experienced revenue and cost growth rates that were 21 and 18 percentage points, respectively, below hospitals in low HMO areas. We also found that, conditional on overall HMO penetration level, hospitals in areas with high for-profit HMO penetration experienced revenue and cost growth rates that were 10 percentage points below hospitals in areas with low for-profit penetration areas; the difference was especially evident within high HMO penetration areas.

Design of polarized infrared athermal telephoto objective for penetrating the fog

NASA Astrophysics Data System (ADS)

Gao, Duorui; Fu, Qiang; Zhao, Zhao; Zhao, Bin; Zhong, Lijun; Zhan, Juntong

2014-11-01

Polarized infrared imaging technology is a new detection technique which own the ability of spying through the fog, highlighting the target and recognizing the forgeries, these characters make it a good advantage of increasing the work distance in the fog. Compared to the traditional infrared imaging method, polarized infrared imaging can identify the background and target easily, that is the most distinguishing feature of polarized infrared imaging technology. Owning to the large refractive index of the infrared material, temperature change will bring defocus seriously, athermal infrared objective is necessarily. On the other hand, athermal objective has large total length, and hard to be integrated for their huge volume. However telephoto objective has the character of small volume and short total length. The paper introduce a method of polarized and athermal infrared telephoto objective which can spy the fog. First assign the optical power of the fore group and the rear group on the basis of the principle of telephoto objective, the power of the fore group is positive and the rear group is negative; then distribute the optical power within each group to realize the ability of athermalization, finally computer-aided software is used to correct aberration. In order to prove the feasibility of the scheme, an athermal optical system was designed by virtue of ZEMAX software which works at 8~12 µm, the focal length of 150mm, F number is 2, and total length of the telephoto objective is 120mm. The environment temperature analysis shows that the optical system have stable imaging quality, MTF is close to diffraction limit. This telephoto objective is available for infrared polarized imaging.

Detecting defects in conifers with ground penetrating radar: applications and challenges

Treesearch

J.R. Butnor; M.L. Pruyn; D.C. Shaw; M.E. Harmon; A.N. Mucciardi; M.G. Ryan

2009-01-01

Our objective was to test ground penetrating radar (GPR) to non-destructively estimate decay volumes in living coniferous trees. GPR is geophysical tool which uses an antenna to propagate short bursts of electromagnetic energy in solid materials and measure the two-way travel time and amplitude of reflected signals. We compared estimates hof bole decay from data...

Long-term Pavement Performance Program (LTPP) data analysis support : National Pooled Fund Study TPF-5(013). Effects of multiple freeze cycles and deep frost penetration on pavement performance and cost

DOT National Transportation Integrated Search

2006-11-01

The objectives of this study are to: (1) quantify the effects of frost penetration on pavement performance in climates with deep sustained frost as compared to environments with multiple freeze-thaw cycles, (2) investigate the effect that local adapt...

Use of ground-penetrating radar to study tree roots in the southeastern United States

Treesearch

John R. Butnor; J.A. Doolittle; L. Kress; Susan Cohen; Kurt H. Johnsen

2001-01-01

Summary: The objectives of our study were to assess the feasibility of using ground-penetrating radar (GPR) to study roots over a broad range of soil conditions in the southeastern United States. Study sites were located in the Southern Piedmont, Carolina Sandhills and Atlantic Coast Flatwoods. At each site, we tested for selection of the appropriate...

Development of a Plastic Embedding Method for Large-Volume and Fluorescent-Protein-Expressing Tissues

PubMed Central

Yang, Zhongqin; Hu, Bihe; Zhang, Yuhui; Luo, Qingming; Gong, Hui

2013-01-01

Fluorescent proteins serve as important biomarkers for visualizing both subcellular organelles in living cells and structural and functional details in large-volume tissues or organs. However, current techniques for plastic embedding are limited in their ability to preserve fluorescence while remaining suitable for micro-optical sectioning tomography of large-volume samples. In this study, we quantitatively evaluated the fluorescence preservation and penetration time of several commonly used resins in a Thy1-eYFP-H transgenic whole mouse brain, including glycol methacrylate (GMA), LR White, hydroxypropyl methacrylate (HPMA) and Unicryl. We found that HMPA embedding doubled the eYFP fluorescence intensity but required long durations of incubation for whole brain penetration. GMA, Unicryl and LR White each penetrated the brain rapidly but also led to variable quenching of eYFP fluorescence. Among the fast-penetrating resins, GMA preserved fluorescence better than LR White and Unicryl. We found that we could optimize the GMA formulation by reducing the polymerization temperature, removing 4-methoxyphenol and adjusting the pH of the resin solution to be alkaline. By optimizing the GMA formulation, we increased percentage of eYFP fluorescence preservation in GMA-embedded brains nearly two-fold. These results suggest that modified GMA is suitable for embedding large-volume tissues such as whole mouse brain and provide a novel approach for visualizing brain-wide networks. PMID:23577174

Water Penetration through a Superhydrophobic Mesh During a Drop Impact.

PubMed

Ryu, Seunggeol; Sen, Prosenjit; Nam, Youngsuk; Lee, Choongyeop

2017-01-06

When a water drop impacts a mesh having submillimeter pores, a part of the drop penetrates through the mesh if the impact velocity is sufficiently large. Here we show that different surface wettability, i.e., hydrophobicity and superhydrophobicity, leads to different water penetration dynamics on a mesh during drop impact. We show, despite the water repellence of a superhydrophobic surface, that water can penetrate a superhydrophobic mesh more easily (i.e., at a lower impact velocity) over a hydrophobic mesh via a penetration mechanism unique to a superhydrophobic mesh. On a superhydrophobic mesh, the water penetration can occur during the drop recoil stage, which appears at a lower impact velocity than the critical impact velocity for water penetration right upon impact. We propose that this unique water penetration on a superhydrophobic mesh can be attributed to the combination of the hydrodynamic focusing and the momentum transfer from the water drop when it is about to bounce off the surface, at which point the water drop retrieves most of its kinetic energy due to the negligible friction on superhydrophobic surfaces.

Water Penetration through a Superhydrophobic Mesh During a Drop Impact

NASA Astrophysics Data System (ADS)

Ryu, Seunggeol; Sen, Prosenjit; Nam, Youngsuk; Lee, Choongyeop

2017-01-01

When a water drop impacts a mesh having submillimeter pores, a part of the drop penetrates through the mesh if the impact velocity is sufficiently large. Here we show that different surface wettability, i.e., hydrophobicity and superhydrophobicity, leads to different water penetration dynamics on a mesh during drop impact. We show, despite the water repellence of a superhydrophobic surface, that water can penetrate a superhydrophobic mesh more easily (i.e., at a lower impact velocity) over a hydrophobic mesh via a penetration mechanism unique to a superhydrophobic mesh. On a superhydrophobic mesh, the water penetration can occur during the drop recoil stage, which appears at a lower impact velocity than the critical impact velocity for water penetration right upon impact. We propose that this unique water penetration on a superhydrophobic mesh can be attributed to the combination of the hydrodynamic focusing and the momentum transfer from the water drop when it is about to bounce off the surface, at which point the water drop retrieves most of its kinetic energy due to the negligible friction on superhydrophobic surfaces.

Multi-Mounted X-Ray Computed Tomography.

PubMed

Fu, Jian; Liu, Zhenzhong; Wang, Jingzheng

2016-01-01

Most existing X-ray computed tomography (CT) techniques work in single-mounted mode and need to scan the inspected objects one by one. It is time-consuming and not acceptable for the inspection in a large scale. In this paper, we report a multi-mounted CT method and its first engineering implementation. It consists of a multi-mounted scanning geometry and the corresponding algebraic iterative reconstruction algorithm. This approach permits the CT rotation scanning of multiple objects simultaneously without the increase of penetration thickness and the signal crosstalk. Compared with the conventional single-mounted methods, it has the potential to improve the imaging efficiency and suppress the artifacts from the beam hardening and the scatter. This work comprises a numerical study of the method and its experimental verification using a dataset measured with a developed multi-mounted X-ray CT prototype system. We believe that this technique is of particular interest for pushing the engineering applications of X-ray CT.

Industrial radiography with cosmic-ray muons: A progress report

NASA Astrophysics Data System (ADS)

Gilboy, W. B.; Jenneson, P. M.; Simons, S. J. R.; Stanley, S. J.; Rhodes, D.

2007-09-01

Cosmic-ray produced muons arrive at the surface of the earth with enormous energies ranging up to 1012 GeV. There have been sporadic attempts to exploit their extreme penetration through matter to probe the internal structures of very large objects, including an Egyptian pyramid and a volcano but their very low intensity per unit area ( ≈1 cm-2 per min) generally restricts the practicably attainable spatial resolution to large dimensions. Nevertheless the more intense low energy region of the muon spectrum has recently been shown to be capable of detecting high-Z objects with dimensions of the order of 10 cm hidden inside large transport containers in measurement times of minutes. These various developments have encouraged further studies of potential industrial uses of cosmic-ray muons in industrial applications. In order to gain maximum benefit from the low muon flux large area detectors are required and plastic scintillators offer useful advantages in size, cost and simplicity. Scintillator slabs up to 1 m2 square and 76.2 mm thick are undergoing testing for applications in the nuclear industry. The most direct approach employs photomultiplier tubes at each corner to measure the relative sizes of muon induced pulses to determine the location of each muon track passing through the scintillator. The performance of this technique is reported and its imaging potential is assessed.

Method and apparatus for shadow aperture backscatter radiography (SABR) system and protocol

NASA Technical Reports Server (NTRS)

Shedlock, Daniel (Inventor); Jacobs, Alan M. (Inventor); Jacobs, Sharon Auerback (Inventor); Dugan, Edward (Inventor)

2010-01-01

A shadow aperture backscatter radiography (SABR) system includes at least one penetrating radiation source for providing a penetrating radiation field, and at least one partially transmissive radiation detector, wherein the partially transmissive radiation detector is interposed between an object region to be interrogated and the radiation source. The partially transmissive radiation detector transmits a portion of the illumination radiation field. A shadow aperture having a plurality of radiation attenuating regions having apertures therebetween is disposed between the radiation source and the detector. The apertures provide illumination regions for the illumination radiation field to reach the object region, wherein backscattered radiation from the object is detected and generates an image by the detector in regions of the detector that are shadowed by the radiation attenuation regions.

Mathematical modeling of intraperitoneal drug delivery: simulation of drug distribution in a single tumor nodule.

PubMed

Steuperaert, Margo; Falvo D'Urso Labate, Giuseppe; Debbaut, Charlotte; De Wever, Olivier; Vanhove, Christian; Ceelen, Wim; Segers, Patrick

2017-11-01

The intraperitoneal (IP) administration of chemotherapy is an alternative treatment for peritoneal carcinomatosis, allowing for higher intratumor concentrations of the cytotoxic agent compared to intravenous administration. Nevertheless, drug penetration depths are still limited to a few millimeters. It is thus necessary to better understand the limiting factors behind this poor penetration in order to improve IP chemotherapy delivery. By developing a three-dimensional computational fluid dynamics (CFD) model for drug penetration in a tumor nodule, we investigated the impact of a number of key parameters on the drug transport and penetration depth during IP chemotherapy. Overall, smaller tumors showed better penetration than larger ones, which could be attributed to the lower IFP in smaller tumors. Furthermore, the model demonstrated large improvements in penetration depth by subjecting the tumor nodules to vascular normalization therapy, and illustrated the importance of the drug that is used for therapy. Explicitly modeling the necrotic core had a limited effect on the simulated penetration. Similarly, the penetration depth remained virtually constant when the Darcy permeability of the tissue changed. Our findings illustrate that the developed parametrical CFD model is a powerful tool providing more insight in the drug transport and penetration during IP chemotherapy.

HMO penetration and the geographic mobility of practicing physicians.

PubMed

Polsky, D; Kletke, P R; Wozniak, G D; Escarce, J J

2000-09-01

In this study, we assessed the influence of changes in health maintenance organization (HMO) penetration on the probability that established patient care physicians relocated their practices or left patient care altogether. For physicians who relocated their practices, we also assessed the impact of HMO penetration on their destination choices. We found that larger increases in HMO penetration decreased the probability that medical/surgical specialists in early career stayed in patient care in the same market, but had no impact on generalists, hospital-based specialists, or mid career medical/surgical specialists. We also found that physicians who relocated their practices were much more likely to choose destination markets with the same level of HMO penetration or lower HMO penetration compared with their origin markets than they were to choose destination markets with higher HMO penetration. The largely negligible impact of changes in HMO penetration on established physicians' decisions to relocate their practices or leave patient care is consistent with high relocation and switching costs. Relocating physicians' attraction to destination markets with the same level of HMO penetration as their origin markets suggests that, while physicians' styles of medical practice may adapt to changes in market conditions, learning new practice styles is costly.

Effect of Liquid Penetrant Sensitivity on Probability of Detection

NASA Technical Reports Server (NTRS)

Parker, Bradford H.

2011-01-01

The objective of the task is to investigate the effect of liquid penetrant sensitivity level on probability of detection (POD) of cracks in various metals. NASA-STD-5009 currently requires the use of only sensitivity level 4 liquid penetrants for NASA Standard Level inspections. This requirement is based on the fact that the data used to establish the reliably detectable flaw sizes penetrant inspection was from studies performed in the 1970s using penetrant deemed to be equivalent only to modern day sensitivity level 4 penetrants. However, many NDE contractors supporting NASA Centers routinely use sensitivity level 3 penetrants. Because of the new NASA-STD-5009 requirement, these contractors will have to either shift to sensitivity level 4 penetrants or perform formal POD demonstration tests to qualify their existing process. We propose a study to compare the POD generated for two penetrant manufactures, Sherwin and Magnaflux, and for the two most common penetrant inspection methods, water washable and post emulsifiable, hydrophilic. NDE vendors local to GSFC will be employed. A total of six inspectors will inspect a set of crack panels with a broad range of fatigue crack sizes. Each inspector will perform eight inspections of the panel set using the combination of methods and sensitivity levels described above. At least one inspector will also perform multiple inspections using a fixed technique to investigate repeatability. The hit/miss data sets will be evaluated using both the NASA generated DOEPOD software and the MIL-STD-1823 software.

Prediction of percutaneous absorption in human using three-dimensional human cultured epidermis LabCyte EPI-MODEL.

PubMed

Hikima, Tomohiro; Kaneda, Noriaki; Matsuo, Kyouhei; Tojo, Kakuji

2012-01-01

The objective of this study is to establish a relationship of the skin penetration parameters between the three-dimensional cultured human epidermis LabCyte EPI-MODEL (LabCyte) and hairless mouse (HLM) skin penetration in vitro and to predict the skin penetration and plasma concentration profile in human. The skin penetration experiments through LabCyte and HLM skin were investigated using 19 drugs that have a different molecular weight and lipophilicity. The penetration flux for LabCyte reached 30 times larger at maximum than that for HLM skin. The human data can be estimated from the in silico approach with the diffusion coefficient (D), the partition coefficient (K) and the skin surface concentration (C) of drugs by assuming the bi-layer skin model for both LabCyte and HLM skin. The human skin penetration of β-estradiol, prednisolone, testosterone and ethynylestradiol was well agreed between the simulated profiles and in vitro experimental data. Plasma concentration profiles of β-estradiol in human were also simulated and well agreed with the clinical data. The present alternative method may decrease human or animal skin experiment for in vitro skin penetration.

Glass transition temperatures of liquid prepolymers obtained by thermal penetrometry

NASA Technical Reports Server (NTRS)

Potts, J. E., Jr.; Ashcraft, A. C.

1973-01-01

Thermal penetrometry is experimental technique for detecting temperature at which frozen prepolymer becomes soft enough to be pierced by weighted penetrometer needle; temperature at which this occurs is called penetration temperature. Apparatus used to obtain penetration temperatures can be set up largely from standard parts.

Diagnosis and Treatment of Hardware Disease.

PubMed

Miesner, Matt D; Reppert, Emily J

2017-11-01

Eating habits in cattle are less discriminant than other ruminants, and they more often accidentally ingest strange objects while feeding. Penetrating foreign bodies may cause mild to severe peritonitis, penetrate the diaphragm to cause pleuritis or pericarditis, or cause localized abscesses in the thorax or abdomen. Because these objects are most often metal, a common term for this problem is hardware disease. An accurate history and thorough physical examination often yields a diagnosis; however, ancillary diagnostics can enhance accuracy and disease magnitude before exploratory surgery. Treatment encompasses controlling infection and inflammation and foreign body removal; preventive measures are emphasized. Copyright © 2017 Elsevier Inc. All rights reserved.

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems.

PubMed

Glover, Jack L; Hudson, Lawrence T

2016-06-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in a US national aviation security standard.

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems

PubMed Central

Glover, Jack L.; Hudson, Lawrence T.

2016-01-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in a US national aviation security standard. PMID:27499586

An objectively-analyzed method for measuring the useful penetration of x-ray imaging systems

NASA Astrophysics Data System (ADS)

Glover, Jack L.; Hudson, Lawrence T.

2016-06-01

The ability to detect wires is an important capability of the cabinet x-ray imaging systems that are used in aviation security as well as the portable x-ray systems that are used by domestic law enforcement and military bomb squads. A number of national and international standards describe methods for testing this capability using the so called useful penetration test metric, where wires are imaged behind different thicknesses of blocking material. Presently, these tests are scored based on human judgments of wire visibility, which are inherently subjective. We propose a new method in which the useful penetration capabilities of an x-ray system are objectively evaluated by an image processing algorithm operating on digital images of a standard test object. The algorithm advantageously applies the Radon transform for curve parameter detection that reduces the problem of wire detection from two dimensions to one. The sensitivity of the wire detection method is adjustable and we demonstrate how the threshold parameter can be set to give agreement with human-judged results. The method was developed to be used in technical performance standards and is currently under ballot for inclusion in an international aviation security standard.

The Lightning Electromagnetic Pulse Coupling Effect Inside the Shielding Enclosure With Penetrating Wire

NASA Astrophysics Data System (ADS)

Jiao, Xue; Yang, Bo

2017-10-01

To study the lightning electromagnetic pulse (LEMP) coupling and protection problems of shielding enclosure with penetrating wire, we adopt the model with proper size which is close to the practical engineering and the two-step finite-difference time-domain (FDTD) method is used for calculation in this paper. It is shown that the coupling voltage on the circuit lead inside the enclosure increases about 34 dB, when add 1.0 m long penetrating wire at the aperture, comparing with the case without penetrating wire. Meanwhile, the waveform, has the same wave outline as the lightning current source, shows that the penetrating wire brings a large number of low frequency component into the enclosure. The coupling effect in the enclosure will reduce greatly when penetrating wire has electrical connection with the enclosure at the aperture and the coupling voltage increase only about 12 dB than the case without penetrating wire. Moreover, the results show that though the waveguide pipe can reduce the coupling effect brought by the penetrating wire, the exposing part of penetrating wire can increase the coupling when the penetrating wire outside the enclosure is longer than the waveguide pipe and the longer the exposing part is, the stronger the coupling is.

An Unusual Transorbital Penetrating Injury and Principles of Management

PubMed Central

Dekker, Andrew Peter; El-Sawy, Abdel Hamid; Rejali, Darius Stephen

2014-01-01

The objective of this study was to present an unusual low velocity transorbital penetrating injury. The study design was a clinical record (case report). A 38-year-old gentleman tripped and fell face first onto the wing of an ornamental brass eagle. This penetrated the inferomedial aspect of the right orbit, breaching the lamina papyracea to extend into the ethmoid sinuses and reaching the dura of the anterior cranial fossa. The foreign body was removed in theater under a joint ophthalmology and ENT procedure. The patient was left with reduced visual acuity in the right eye but no other long-term sequelae. Transorbital penetrating injury presents unusual challenges to investigation and management requiring a multidisciplinary approach to prevent significant morbidity and mortality. If managed well the prognosis is good. PMID:25383154

An unusual transorbital penetrating injury and principles of management.

PubMed

Dekker, Andrew Peter; El-Sawy, Abdel Hamid; Rejali, Darius Stephen

2014-12-01

The objective of this study was to present an unusual low velocity transorbital penetrating injury. The study design was a clinical record (case report). A 38-year-old gentleman tripped and fell face first onto the wing of an ornamental brass eagle. This penetrated the inferomedial aspect of the right orbit, breaching the lamina papyracea to extend into the ethmoid sinuses and reaching the dura of the anterior cranial fossa. The foreign body was removed in theater under a joint ophthalmology and ENT procedure. The patient was left with reduced visual acuity in the right eye but no other long-term sequelae. Transorbital penetrating injury presents unusual challenges to investigation and management requiring a multidisciplinary approach to prevent significant morbidity and mortality. If managed well the prognosis is good.

Design and Evaluation of Candidate Pressure Distribution and Air Data System Tile Penetration for the Aeroassist Flight Experiment

NASA Technical Reports Server (NTRS)

Vontheumer, Alfred E.

1990-01-01

This program objectives were to produce a pressure measurements system that penetrates the thermal protection system of a spacecraft and is able to obtain accurate pressure data. The design was tested vibro-acoustically, aerothermally, and structurally and found to be adequate. This design is a possible replacement of the current pressure system on the orbiter.

The Association between Medicare Advantage Market Penetration and Diabetes in the United States

PubMed Central

Howard, Steven W.; Bernell, Stephanie Lazarus; Wilmott, Jennifer; Casim, M. Faizan; Wang, Jing; Pearson, Lindsey; Byler, Caitlin M.; Zhang, Zidong

2015-01-01

The objective of this study is to explore the extent to which managed care market penetration in the United States is associated with the presence of chronic disease. Diabetes was selected as the chronic disease of interest due to its increasing prevalence as well as the disease management protocols that can lessen disease complications. We hypothesized that greater managed care market penetration would be associated with (1) lower prevalence of diabetes and (2) lower prevalence of diabetes-related comorbidities (DRCs) among diabetics. Data for this analysis came from two sources. We merged Medicare Advantage (MA) market penetration data from the Centers for Medicare and Medicaid Services (CMS) with data from the Medical Expenditure Panel Survey (MEPS) (2004–2008). Results suggest that county-level MA market penetration is not significantly associated with prevalence of diabetes or DRCs. That finding is quite interesting in that managed care market penetration has been shown to have an effect on utilization of inpatient services. It may be that managed care protocols do not offer the same benefits beyond the inpatient setting. PMID:26501052

The Association between Medicare Advantage Market Penetration and Diabetes in the United States.

PubMed

Howard, Steven W; Bernell, Stephanie Lazarus; Wilmott, Jennifer; Casim, M Faizan; Wang, Jing; Pearson, Lindsey; Byler, Caitlin M; Zhang, Zidong

2015-01-01

The objective of this study is to explore the extent to which managed care market penetration in the United States is associated with the presence of chronic disease. Diabetes was selected as the chronic disease of interest due to its increasing prevalence as well as the disease management protocols that can lessen disease complications. We hypothesized that greater managed care market penetration would be associated with (1) lower prevalence of diabetes and (2) lower prevalence of diabetes-related comorbidities (DRCs) among diabetics. Data for this analysis came from two sources. We merged Medicare Advantage (MA) market penetration data from the Centers for Medicare and Medicaid Services (CMS) with data from the Medical Expenditure Panel Survey (MEPS) (2004-2008). Results suggest that county-level MA market penetration is not significantly associated with prevalence of diabetes or DRCs. That finding is quite interesting in that managed care market penetration has been shown to have an effect on utilization of inpatient services. It may be that managed care protocols do not offer the same benefits beyond the inpatient setting.

Characterizing Discourse Deficits Following Penetrating Head Injury: A Preliminary Model

ERIC Educational Resources Information Center

Coelho, Carl; Le, Karen; Mozeiko, Jennifer; Hamilton, Mark; Tyler, Elizabeth; Krueger, Frank; Grafman, Jordan

2013-01-01

Purpose: Discourse analyses have demonstrated utility for delineating subtle communication deficits following closed head injuries (CHIs). The present investigation examined the discourse performance of a large group of individuals with penetrating head injury (PHI). Performance was also compared across 6 subgroups of PHI based on lesion locale. A…

Bioactive glass fillers reduce bacterial penetration into marginal gaps for composite restorations

PubMed Central

Khvostenko, D.; Hilton, T. J.; Ferracane, J. L.; Mitchell, J. C.; Kruzic, J. J.

2015-01-01

Objectives Bioactive glass (BAG) is known to possess antimicrobial and remineralizing properties; however, the use of BAG as a filler for resin based composite restorations to slow recurrent caries has not been studied. Accordingly, the objective of this study was to investigate the effect of 15 wt% BAG additions to a resin composite on bacterial biofilms penetrating into marginal gaps of simulated tooth fillings in vitro during cyclic mechanical loading. Methods Human molars were machined into approximately 3 mm thick disks of dentin and 1.5–2 mm deep composite restorations were placed. A narrow 15–20 micrometer wide dentin-composite gap was allowed to form along half of the margin by not applying dental adhesive to that region. Two different 72 wt% filled composites were used, one with 15 wt% BAG filler (15BAG) and the balance silanated strontium glass and one filled with OX-50 and silanated strontium glass without BAG (0BAG – control). Samples of both groups had Streptococcus mutans biofilms grown on the surface and were tested inside a bioreactor for two weeks while subjected to periods of cyclic mechanical loading. After post-test biofilm viability was confirmed, each specimen was fixed in glutaraldehyde, gram positive stained, mounted in resin and cross-sectioned to reveal the gap profile. Depth of biofilm penetration for 0BAG and 15BAG was quantified as the fraction of gap depth. The data were compared using a Student’s t-test. Results The average depth of bacterial penetration into the marginal gap for the 15BAG samples was significantly smaller (~61%) in comparison to 0BAG, where 100% penetration was observed for all samples with the biofilm penetrating underneath of the restoration in some cases. Significance BAG containing resin dental composites reduce biofilm penetration into marginal gaps of simulated tooth restorations. This suggests BAG containing composites may have the potential to slow the development and propagation of secondary tooth decay at restoration margins. PMID:26621028

HMO penetration, competition, and risk-adjusted hospital mortality.

PubMed Central

Mukamel, D B; Zwanziger, J; Tomaszewski, K J

2001-01-01

OBJECTIVE: HMOs have been shown to have an effect on the care provided directly to their enrollees. They may also influence the care provided to individuals in fee-for-service plans through a spill-over effect. The objective of this study was to investigate the associations among HMO market penetration, HMO and hospital competition, and the quality of care received by Medicare fee-for-service patients measured by risk-adjusted hospital mortality rates. DATA SOURCES: The 1990 data for 1,927 hospitals in 134 metropolitan statistical areas (with five or more hospitals) included Medicare fee-for-service risk-adjusted mortality rates from the Medicare Hospital Information Reports, hospital characteristics from the American Hospital Association annual survey, and HMO market penetration and competition calculated from InterStudy and Group Health Association of America data. STUDY DESIGN: Statistical regression techniques were used to identify the associations between HMO market penetration, competition, and risk-adjusted mortality, controlling for other hospital characteristics and region. PRINCIPAL FINDINGS: Higher HMO market penetration and to a lesser degree increased HMO competition were associated with better mortality outcomes for fee-for-service Medicare enrollees. Competition between hospitals did not exhibit a significant association. CONCLUSIONS: HMOs may have a spill-over effect on quality of care received by individuals enrolled in fee-for-service plans. These findings may be explained by a positive effect on local practice styles or a preferential selection by HMOs for areas with better hospital care. PMID:11775665

Evaluating the safety impact of adaptive cruise control in traffic oscillations on freeways.

PubMed

Li, Ye; Li, Zhibin; Wang, Hao; Wang, Wei; Xing, Lu

2017-07-01

Adaptive cruise control (ACC) has been considered one of the critical components of automated driving. ACC adjusts vehicle speeds automatically by measuring the status of the ego-vehicle and leading vehicle. Current commercial ACCs are designed to be comfortable and convenient driving systems. Little attention is paid to the safety impacts of ACC, especially in traffic oscillations when crash risks are the highest. The primary objective of this study was to evaluate the impacts of ACC parameter settings on rear-end collisions on freeways. First, the occurrence of a rear-end collision in a stop-and-go wave was analyzed. A car-following model in an integrated ACC was developed for a simulation analysis. The time-to-collision based factors were calculated as surrogate safety measures of the collision risk. We also evaluated different market penetration rates considering that the application of ACC will be a gradual process. The results showed that the safety impacts of ACC were largely affected by the parameters. Smaller time delays and larger time gaps improved safety performance, but inappropriate parameter settings increased the collision risks and caused traffic disturbances. A higher reduction of the collision risk was achieved as the ACC vehicle penetration rate increased, especially in the initial stage with penetration rates of less than 30%. This study also showed that in the initial stage, the combination of ACC and a variable speed limit achieved better safety improvements on congested freeways than each single technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

Western Wind and Solar Integration Study Phase 3A: Low Levels of Synchronous Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Nicholas W.; Leonardi, Bruno; D'Aquila, Robert

The stability of the North American electric power grids under conditions of high penetrations of wind and solar is a significant concern and possible impediment to reaching renewable energy goals. The 33% wind and solar annual energy penetration considered in this study results in substantial changes to the characteristics of the bulk power system. This includes different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior from wind and solar generation. The Western Wind and Solar Integration Study (WWSIS), sponsored by the U.S. Department of Energy, is one of the largest regional solar andmore » wind integration studies to date. In multiple phases, it has explored different aspects of the question: Can we integrate large amounts of wind and solar energy into the electric power system of the West? The work reported here focused on the impact of low levels of synchronous generation on the transient stability performance in one part of the region in which wind generation has displaced synchronous thermal generation under highly stressed, weak system conditions. It is essentially an extension of WWSIS-3. Transient stability, the ability of the power system to maintain synchronism among all elements following disturbances, is a major constraint on operations in many grids, including the western U.S. and Texas systems. These constraints primarily concern the performance of the large-scale bulk power system. But grid-wide stability concerns with high penetrations of wind and solar are still not thoroughly understood. This work focuses on 'traditional' fundamental frequency stability issues, such as maintaining synchronism, frequency, and voltage. The objectives of this study are to better understand the implications of low levels of synchronous generation and a weak grid on overall system performance by: 1) Investigating the Western Interconnection under conditions of both high renewable generation (e.g., wind and solar) and low synchronous generation (e.g., significant coal power plant decommitment or retirement); and 2) Analyzing both the large-scale stability of the Western Interconnection and regional stability issues driven by more geographically dispersed renewable generation interacting with a transmission grid that evolved with large, central station plants at key nodes. As noted above, the work reported here is an extension of the research performed in WWSIS-3.« less

Galileo to Jupiter: Probing the Planet and Mapping Its Moons

NASA Technical Reports Server (NTRS)

1979-01-01

The first project to use the space shuttle as an interplanetary launch vehicle, the Galileo mission is designed to obtain information about the origin and evolution of the solar system by studying large-scale phenomena on Jupiter and its satellites. Aimed towards Mars to obtain gravity assist, the orbiting spacecraft will deploy a probe, which penetrating the Jovian atmosphere, will transmit data for approximately an hour. The spacecraft itself will inspect the atmospheres, ionospheres, and surfaces of Ganymede, Io, Europa, and Callisto, as well as determine their magnetic and gravitational properties. The experiments to be conducted and their scientific objectives are described. Known facts about the Jovian system are reviewed.

Visibility through the gaseous smoke in airborne remote sensing using a DSLR camera

NASA Astrophysics Data System (ADS)

Chabok, Mirahmad; Millington, Andrew; Hacker, Jorg M.; McGrath, Andrew J.

2016-08-01

Visibility and clarity of remotely sensed images acquired by consumer grade DSLR cameras, mounted on an unmanned aerial vehicle or a manned aircraft, are critical factors in obtaining accurate and detailed information from any area of interest. The presence of substantial haze, fog or gaseous smoke particles; caused, for example, by an active bushfire at the time of data capture, will dramatically reduce image visibility and quality. Although most modern hyperspectral imaging sensors are capable of capturing a large number of narrow range bands of the shortwave and thermal infrared spectral range, which have the potential to penetrate smoke and haze, the resulting images do not contain sufficient spatial detail to enable locating important objects or assist search and rescue or similar applications which require high resolution information. We introduce a new method for penetrating gaseous smoke without compromising spatial resolution using a single modified DSLR camera in conjunction with image processing techniques which effectively improves the visibility of objects in the captured images. This is achieved by modifying a DSLR camera and adding a custom optical filter to enable it to capture wavelengths from 480-1200nm (R, G and Near Infrared) instead of the standard RGB bands (400-700nm). With this modified camera mounted on an aircraft, images were acquired over an area polluted by gaseous smoke from an active bushfire. Processed data using our proposed method shows significant visibility improvements compared with other existing solutions.

Traumatic injuries of the diaphragm: overview of imaging findings and diagnosis.

PubMed

Hammer, Mark M; Raptis, Demetrios A; Mellnick, Vincent M; Bhalla, Sanjeev; Raptis, Constantine A

2017-04-01

Injuries to the diaphragm muscle occur in penetrating and severe blunt trauma and can lead to delayed hernia formation. Computed tomography is the mainstay in the diagnosis of these injuries, which may be subtle at presentation. Imaging findings differ between blunt and penetrating trauma. Key features in blunt trauma include diaphragm fragment distraction and organ herniation because of increased intra-abdominal pressure. In penetrating trauma, herniation is uncommon, and the trajectory of the object is critical in making the diagnosis of diaphragm injury in these patients. Radiologists must keep a high index of suspicion for injury to the diaphragm in cases of trauma to the chest or abdomen.

Superconducting Effects in Optimization of Magnetic Penetration Thermometers for X-ray Microcalorimeters

NASA Technical Reports Server (NTRS)

Stevenson, Thomas R.; Balvin, M. A.; Denis, K. L.; Hsieh, W.-T.; Sadleir, J. E.; Bandler, Simon E.; Busch, Sarah E.; Merrell, W.; Kelly, Daniel P.; Nagler, Peter C.;

The effect of simulated air conditions on N95 filtering facepiece respirators performance.

PubMed

Ramirez, Joel A; O'Shaughnessy, Patrick T

2016-07-01

The objective of this study was to determine the effect of several simulated air environmental conditions on the particle penetration and the breathing resistance of two N95 filtering facepiece respirator (FFR) models. The particle penetration and breathing resistance of the respirators were evaluated in a test system developed to mimic inhalation and exhalation breathing while relative humidity and temperature were modified. Breathing resistance was measured over 120 min using a calibrated pressure transducer under four different temperature and relative humidity conditions without aerosol loading. Particle penetration was evaluated before and after the breathing resistance test at room conditions using a sodium chloride aerosol measured with a scanning mobility particle sizer. Results demonstrated that increasing relative humidity and lowering external temperature caused significant increases in breathing resistance (p < 0.001). However, these same conditions did not influence the penetration or most penetrating particle size of the tested FFRs. The increase in breathing resistance varied by FFR model suggesting that some FFR media are less influenced by high relative humidity.

Factors affecting flood insurance penetration in residential properties in Johor Malaysia

NASA Astrophysics Data System (ADS)

Godwin Aliagha, U.; Ewe Jin, T.; Weng Choong, W.; Nadzri Jaafar, M.

2014-04-01

High impact flood has virtually become an annual experience in Malaysia, yet flood insurance has remained a grossly neglected part of comprehensive integrated flood risk management. Using discriminant analysis, this study seeks to indentify the demand-side variables that best predict flood insurance penetration and risk aversion between two groups of residential homeowners in three districts of Johor State, Malaysia: those who purchased flood insurance and the group that did not. Our result revealed 34% penetration rate with Kota Tinggi district having the highest penetration (44%) and thus, the highest degree of flood risk aversion. The Wilks' Lambda F test for equality of group means, SCDFC, structure correlation and canonical correlation have clearly shown that there are strong significant attribute differences between the two groups of homeowners based on measures of objective flood risk exposure, subjective risk perception, and socio-economic cum demographic variables. However, measures of subjective risk perception were found more predictive of flood insurance penetration and flood risk aversion.

Skin penetration assessment of less lethal kinetic energy munitions.

PubMed

Bir, Cynthia A; Stewart, Shelby J; Wilhelm, Marianne

2005-11-01

The development of less-lethal technologies has provided law enforcement personnel with an alternative to lethal force. Although the less lethal projectile was produced to engender non-penetrating wounds, case studies show that there have been a number of reported penetrating injuries ranging from minor to significant in morbidity. The objective of this study was to determine the energy per unit area required to penetrate various regions of the body. Eight unembalmed postmortem human specimens were procured for this testing. Each specimen sustained a maximum of 25 impacts consisting of shots to the anterior and posterior thorax, abdomen, and legs. A 12-gauge, fin-stabilized, rubber rocket round was used as the impactor for all of the conducted tests. The energy density required for 50% risk of penetration varied from 23.99 J/cm2 for the location on the anterior rib (p = 0.000) to 52.74 J/cm2 for the location on the posterior rib (p = 0.001).

Biomechanics of penetrating trauma.

PubMed

Yoganandan, N; Pintar, F A

1997-01-01

It is well known that injuries and deaths due to penetrating projectiles have become a national and an international epidemic in Western society. The application of biomedical engineering to solve day-to-day problems has produced considerable advances in safety and mitigation/prevention of trauma. The study of penetrating trauma has been largely in the military domain where war-time specific applications were advanced with the use of high-velocity weapons. With the velocity and weapon caliber in the civilian population at half or less compared with the military counterpart, wound ballistics is a largely different problem in today's trauma centers. The principal goal of the study of penetrating injuries in the civilian population is secondary prevention and optimized emergency care after occurrence. A thorough understanding of the dynamic biomechanics of penetrating injuries quantifies missile type, caliber, and velocity to hard and soft tissue damage. Such information leads to a comprehensive assessment of the acute and long-term treatment of patients with penetrating injuries. A review of the relevant military research applied to the civilian domain and presentation of new technology in the biomechanical study of these injuries offer foundation to this field. Relevant issues addressed in this review article include introduction of the military literature, the need for secondary prevention, environmental factors including projectile velocity and design, experimental studies with biological tissues and physical models, and mathematical simulations and analyses. Areas of advancement are identified that enables the pursuit of biomechanics research in order to arrive at better secondary prevention strategies.

Health insurance reform and HMO penetration in the small group market.

PubMed

Buchmueller, Thomas C; Liu, Su

This study uses data from several national employer surveys conducted between the late 1980s and the mid-1990s to investigate the effect of state-level underwriting reforms on HMO penetration in the small group health insurance market. We identify reform effects by exploiting cross-state variation in the timing and content of reform legislation and by using mid-sized and large employers, which were not affected by the legislation, as within-state control groups. While it is difficult to disentangle the effect of state reforms from other factors affecting HMO penetration in the small group markets, the results suggest a positive relationship between insurance market regulations and HMO penetration.

COST Action TU1208 - Working Group 3 - Electromagnetic modelling, inversion, imaging and data-processing techniques for Ground Penetrating Radar

NASA Astrophysics Data System (ADS)

Pajewski, Lara; Giannopoulos, Antonios; Sesnic, Silvestar; Randazzo, Andrea; Lambot, Sébastien; Benedetto, Francesco; Economou, Nikos

2017-04-01

This work aims at presenting the main results achieved by Working Group (WG) 3 "Electromagnetic methods for near-field scattering problems by buried structures; data processing techniques" of the COST (European COoperation in Science and Technology) Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar" (www.GPRadar.eu, www.cost.eu). The main objective of the Action, started in April 2013 and ending in October 2017, is to exchange and increase scientific-technical knowledge and experience of Ground Penetrating Radar (GPR) techniques in civil engineering, whilst promoting in Europe the effective use of this safe non-destructive technique. The Action involves more than 150 Institutions from 28 COST Countries, a Cooperating State, 6 Near Neighbour Countries and 6 International Partner Countries. Among the most interesting achievements of WG3, we wish to mention the following ones: (i) A new open-source version of the finite-difference time-domain simulator gprMax was developed and released. The new gprMax is written in Python and includes many advanced features such as anisotropic and dispersive-material modelling, building of realistic heterogeneous objects with rough surfaces, built-in libraries of antenna models, optimisation of parameters based on Taguchi's method - and more. (ii) A new freeware CAD was developed and released, for the construction of two-dimensional gprMax models. This tool also includes scripts easing the execution of gprMax on multi-core machines or network of computers and scripts for a basic plotting of gprMax results. (iii) A series of interesting freeware codes were developed will be released by the end of the Action, implementing differential and integral forward-scattering methods, for the solution of simple electromagnetic problems by buried objects. (iv) An open database of synthetic and experimental GPR radargrams was created, in cooperation with WG2. The idea behind this initiative is to give researchers the opportunity of testing and validating, against reliable data, their electromagnetic-modelling, inversion, imaging and processing algorithms. One of the most interesting dataset comes from the IFSTTAR Geophysical Test Site, in Nantes (France): this is an open-air laboratory including a large and deep area, filled with various materials arranged in horizontal compacted slices, separated by vertical interfaces and water-tighted in surface; several objects as pipes, polystyrene hollows, boulders and masonry are embedded in the field. Data were collected by using nine different GPR systems and at different frequencies ranging from 200 MHz to 1 GHz. Moreover, some sections of this test site were modelled by using gprMax and the commercial software CST Microwave Studio. Hence, both experimental and synthetic data are available. Further interesting datasets were collected on roads, bridges, concrete cells, columns - and more. (v) WG3 contributed to the TU1208 Education Pack, an open educational package conceived to teach GPR in University courses. (vi) WG3 was very active in offering training activities. The following courses were successfully organised: Training School (TS) "Microwave Imaging and Diagnostics" (in cooperation with the European School of Antennas; 1st edition: Madonna di Campiglio, Italy, March 2014, 2nd edition: Taormina, Italy, October 2016); TS "Numerical modelling of Ground Penetrating Radar using gprMax" (Thessaloniki, Greece, November 2015); TS "Electromagnetic Modelling Techniques for Ground Penetrating Radar" (Split, Croatia, November 2016). Moreover, WG3 organized a workshop on "Electromagnetic modelling with the Finite-Difference Time-Domain technique" (Nantes, France, February 2014) and a workshop on "Electromagnetic modelling and inversion techniques for GPR" (Davos, Switzerland, April 2016) within the 2016 European Conference on Antennas and Propagation (EuCAP). Acknowledgement: The Authors are deeply grateful to COST (European COoperation in Science and Technology, www.cost.eu), for funding and supporting the COST Action TU1208 "Civil engineering applications of Ground Penetrating Radar" (www.GPRadar.eu).

Prediction of soil frost penetration depth in northwest of Iran using air freezing indices

NASA Astrophysics Data System (ADS)

Mohammadi, H.; Moghbel, M.; Ranjbar, F.

2016-11-01

Information about soil frost penetration depth can be effective in finding appropriate solutions to reduce the agricultural crop damage, transportations, and building facilities. Amongst proper methods to achieve this information are the statistical and empirical models capable of estimating soil frost penetration depth. Therefore, the main objective of this research is to calculate soil frost penetration depth in northwest of Iran during the year 2007-2008 to validate two different models accuracy. To do so, the relationship between air and soil temperature in different depths (5-10-20-30-50-100 cm) at three times of the day (3, 9, and 15 GMT) for 14 weather stations over 7 provinces was analyzed using linear regression. Then, two different air freezing indices (AFIs) including Norwegian and Finn AFI was implemented. Finally, the frost penetration depth was calculated by McKeown method and the accuracy of models determined by actual soil frost penetration depth. The results demonstrated that there is a significant correlation between air and soil depth temperature in all studied stations up to the 30 cm under the surface. Also, according to the results, Norwegian index can be effectively used for determination of soil frost depth penetration and the correlation coefficient between actual and estimated soil frost penetration depth is r = 0.92 while the Finn index overestimates the frost depth in all stations with correlation coefficient r = 0.70.

Imaging assessment of penetrating injury of the neck and face.

PubMed

Offiah, Curtis; Hall, Edward

2012-10-01

Penetrating trauma of the neck and face is a frequent presentation to acute emergency, trauma and critical care units. There remains a steady incidence of both gunshot penetrating injury to the neck and face as well as non-missile penetrating injury-largely, but not solely, knife-related. Optimal imaging assessment of such injuries therefore remains an on-going requirement of the general and specialised radiologist. The anatomy of the neck and face-in particular, vascular, pharyngo-oesophageal, laryngo-tracheal and neural anatomy-demands a more specialised and selective management plan which incorporates specific imaging techniques. The current treatment protocol of injuries of the neck and face has seen a radical shift away from expectant surgical exploration in the management of such injuries, largely as a result of advances in the diagnostic capabilities of multi-detector computed tomography angiography (MDCTA), which is now the first-line imaging modality of choice in such cases. This review aims to highlight ballistic considerations, differing imaging modalities, including MDCTA, that might be utilised to assist in the accurate assessment of these injuries as well as the specific radiological features and patterns of specific organ-system injuries that should be considered and communicated to surgical and critical care teams. TEACHING POINTS : • MDCTA is the first-line imaging modality in penetrating trauma of the neck and, often, of the face • The inherent deformability of a bullet is a significant factor in its tissue-damaging capabilities • MDCTA can provide accurate assessment of visceral injury of the neck as well as vascular injury • Penetrating facial trauma warrants radiological assessment of key adjacent anatomical structures • In-driven fragments of native bone potentiate tissue damage in projectile penetrating facial trauma.

NuSTAR Observations of X-Ray Flares from Young Stellar Objects

NASA Astrophysics Data System (ADS)

Vievering, Juliana; Glesener, Lindsay; Grefenstette, Brian; Smith, David

2018-01-01

Young stellar objects (YSOs), which tend to flare more frequently and at higher temperatures than what is typically observed on Sun-like stars, are excellent targets for studying the physical processes behind large flaring events. In the hard x-ray regime, radiation can penetrate through dense circumstellar material, and it is possible to measure thermal emission from hot plasma and to search for nonthermal emission from accelerated particles, which are key components for understanding the nature of energy release in these flares. Additionally, high-energy x-ray emission can ionize material in the disk, which may have implications for planet formation. To investigate hard x-ray emission from YSOs, three 50ks observations of a star-forming region called rho Ophiuchi have been taken with the Nuclear Spectroscopic Telescope Array (NuSTAR). Through use of direct focusing optics, NuSTAR provides unprecedented sensitivity in the hard x-ray regime, making these YSO observations the first of their kind. Multiple stellar flares have been identified in the data set; here we present the current spectral and timing analyses of the brightest of the these events, exploring the way energy is released as well as the effects of these large flares on the surrounding environment.

Optical microangiography reveals collateral blood perfusion dynamics in mouse cerebral cortex after focal stroke

NASA Astrophysics Data System (ADS)

Baran, Utku; Li, Yuandong; Wang, Ruikang K.

2015-03-01

Arteriolo-arteriolar anastomosis's role in regulating blood perfusion through penetrating arterioles during stroke is yet to be discovered. We apply ultra-high sensitive optical microangiography (UHS-OMAG) and Doppler optical microangiography (DOMAG) techniques to evaluate vessel diameter and red blood cell velocity changes in large number of pial and penetrating arterioles in relation with arteriolo-arteriolar anastomosis (AAA) during and after focal stroke. Thanks to the high sensitivity of UHS-OMAG, we were able to image pial microvasculature up to capillary level through a cranial window (9 mm2), and DOMAG provided clear image of penetrating arterioles up to 500μm depth. Results showed that penetrating arterioles close to a strong AAA connection dilate whereas penetrating arterioles constrict significantly in weaker AAA regions. These results suggest that AAA plays a major role in active regulation of the pial arterioles, and weaker AAA connections lead to poor blood perfusion to penumbra through penetrating arterioles.

Unraveling the mysteries of the Leo Ring: An absorption line study of an unusual gas cloud

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenberg, J. L.; Haislmaier, Karl; Giroux, M. L.

2014-07-20

Since the discovery of the large (2 × 10{sup 9} M{sub ☉}) intergalactic cloud known as the Leo Ring in the 1980s, the origin of this object has been the center of a lively debate. Determining the origin of this object is still important as we develop a deeper understanding of the accretion and feedback processes that shape galaxy evolution. We present Hubble Space Telescope/Cosmic Origins Spectrograph observations of three sightlines near the ring, two of which penetrate the high column density neutral hydrogen gas visible in 21 cm observations of the object. These observations provide the first direct measurementmore » of the metallicity of the gas in the ring, an important clue to its origin. Our best estimate of the metallicity of the ring is ∼10% Z{sub ☉}, higher than expected for primordial gas but lower than expected from an interaction. We discuss possible modifications to the interaction and primordial gas scenarios that would be consistent with this metallicity measurement.« less

Determination of vessel cross-sectional area by thresholding in Radon space

PubMed Central

Gao, Yu-Rong; Drew, Patrick J

2014-01-01

The cross-sectional area of a blood vessel determines its resistance, and thus is a regulator of local blood flow. However, the cross-sections of penetrating vessels in the cortex can be non-circular, and dilation and constriction can change the shape of the vessels. We show that observed vessel shape changes can introduce large errors in flux calculations when using a single diameter measurement. Because of these shape changes, typical diameter measurement approaches, such as the full-width at half-maximum (FWHM) that depend on a single diameter axis will generate erroneous results, especially when calculating flux. Here, we present an automated method—thresholding in Radon space (TiRS)—for determining the cross-sectional area of a convex object, such as a penetrating vessel observed with two-photon laser scanning microscopy (2PLSM). The thresholded image is transformed back to image space and contiguous pixels are segmented. The TiRS method is analogous to taking the FWHM across multiple axes and is more robust to noise and shape changes than FWHM and thresholding methods. We demonstrate the superior precision of the TiRS method with in vivo 2PLSM measurements of vessel diameter. PMID:24736890

Evaluation of different captive bolt lengths and breed influence upon post-stun hind limb and forelimb activity in fed cattle at a commercial slaughter facility.

PubMed

Martin, Miriam S; Kline, Helen C; Wagner, Dana R; Alexander, Lacey R; Edwards-Callaway, Lily N; Grandin, Temple

2018-05-03

The objective of this study was to assess the effects of captive bolt length and breed type on post-stun leg activity in cattle. A total of 2850 Holstein (HOL) and non-Holstein British/Continental bred (NHOL) steers and heifers were observed post-stunning at a large commercial slaughter facility. A pneumatically powered penetrating captive bolt stunner was used with three different bolt lengths: CON, 15.24 cm; MED, 16.51 cm; and LON, 17.78 cm. Hind limb kicking, forelimb activity, take away belt stops, carcass swing and number of knife sticks during exsanguination were recorded for each animal from video recording. Hind limb and forelimb kicks observed ranged from 0 to 25 and 0 to 8, respectively. Analysis of post-stun hind limb and forelimb activity indicated that increasing pneumatically powered penetrating captive bolt length does not decrease post-stun leg activity. There was a higher percentage of cattle experiencing take away belt stops and carcass swing in HOL as compared with NHOL. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Confocal laser scanning microscopy to estimate nanoparticles’ human skin penetration in vitro

PubMed Central

Elmahdy, Akram; Cao, Yachao; Hui, Xiaoying; Maibach, Howard

2017-01-01

Objective With rapid development of nanotechnology, there is increasing interest in nanoparticle (NP) application and its safety and efficacy on human skin. In this study, we utilized confocal laser scanning microscopy to estimate NP skin penetration. Methods Three different-sized polystyrene NPs marked with red fluorescence were applied to human skin, and Calcium Green 5N was used as a counterstain. Dimethyl sulfoxide (DMSO) and ethanol were used as alternative vehicles for NPs. Tape stripping was utilized as a barrier-damaged skin model. Skin biopsies dosed with NPs were incubated at 4°C or 37°C for 24 hours and imaged using confocal laser scanning microscopy. Results NPs were localized in the stratum corneum (SC) and hair follicles without penetrating the epidermis/dermis. Barrier alteration with tape stripping and change in incubation temperature did not induce deeper penetration. DMSO enhanced NP SC penetration but ethanol did not. Conclusion Except with DMSO vehicle, these hydrolyzed polystyrene NPs did not penetrate intact or barrier-damaged human “viable” epidermis. For further clinical relevance, in vivo human skin studies and more sensitive analytic chemical methodology are suggested. PMID:29184403

The Role of Intraoperative Cerebral Angiography in Transorbital Intracranial Penetrating Trauma: A Case Report and Literature Review.

PubMed

Riley, Jonathan P; Boucher, Andrew B; Kim, Denise S; Barrow, Daniel L; Reynolds, Matthew R

2017-01-01

Transorbital intracranial penetrating trauma with a retained intracranial foreign body is a rare event lacking a widely accepted diagnostic and therapeutic algorithm. Intraoperative catheter angiography (IOA) has been advocated by some authorities to rule out cerebrovascular injury before and/or after removal of the object, but no standard of care currently exists. A 19-year-old man was involved in a construction site accident whereby a framing nail penetrated the left globe, traversed the lateral bony orbit, and terminated in the midtemporal lobe. No hematoma or injury to the middle cerebral arteries (MCAs) was apparent on noncontrast head computed tomography (CT) or CT angiography, respectively. The foreign body was removed in the operating room under direct visualization after a frontotemporal craniotomy without incident. No significant venous or arterial bleeding was encountered. All visualized MCA branches appeared intact. Indocyanine green videoangiography performed immediately after object removal showed adequate filling of the MCA branches. Given these uneventful clinical and radiographic findings, IOA was not performed. Postoperative head CT and CT angiography showed no obvious neurovascular injury. On postoperative day 2, the patient was noted to have an expressive aphasia. Cerebral angiography showed absent antegrade filling of the angular artery with some retrograde perfusion. Magnetic resonance imaging confirmed an ischemic infarction in the midtemporal lobe. The patient's expressive aphasia improved to near baseline during his hospitalization and he made an excellent clinical recovery. In transorbital intracranial penetrating trauma with a retained intracranial object, we advocate microsurgical removal of the object under direct visualization followed immediately by IOA. IOA should be strongly considered even in the setting of minimal intraoperative bleeding and normal findings on videoangiography (a course of action that was not followed in the present case). Given that CT angiography and intraoperative videoangiography may miss a potentially treatable traumatic arterial injury, IOA can help determine whether cerebral revascularization may be necessary. Copyright © 2016 Elsevier Inc. All rights reserved.

The impact of a large penetration of intermittent sources on the power system operation and planning

NASA Astrophysics Data System (ADS)

Ausin, Juan Carlos

This research investigated the impact on the power system of a large penetration of intermittent renewable sources, mainly wind and photovoltaic generation. Currently, electrical utilities deal with wind and PV plants as if they were sources of negative demand, that is to say, they have no control over the power output produced. In this way, the grid absorbs all the power fluctuation as if it were coming from a common load. With the level of wind penetration growing so quickly, there is growing concern amongst the utilities and the grid operators, as they will have to deal with a much higher level of fluctuation. In the same way, the potential cost reduction of PV technologies suggests that a similar development may be expected for solar production in the mid term. The first part of the research was focused on the issues that affect utility planning and reinforcement decision making. Although DG is located mainly on the distribution network, a large penetration may alter the flows, not only on the distribution lines, but also on the transmission system and through the transmission - distribution interfaces. The optimal capacity and production costs for the UK transmission network have been calculated for several combinations of load profiles and typical wind/PV output scenarios. A full economic analysis is developed, showing the benefits and disadvantages that a large penetration of these distributed generators may have on transmission system operator reinforcement strategies. Closely related to planning factors are institutional, revelatory, and economic considerations, such as transmission pricing, which may hamper the integration of renewable energy technologies into the electric utility industry. The second part of the research related to the impact of intermittent renewable energy technologies on the second by second, minute by minute, and half-hour by half-hour operations of power systems. If a large integration of these new generators partially replaces the conventional rotating machines the aggregate fluctuation starts to become an important factor, and should be taken into account for the calculation of the balancing requirements. Additional balancing requirements would increase the total balancing cost and this could stop the future development of the intermittent sources.

Radial flow to a partially penetrating well with storage in an anisotropic confined aquifer

NASA Astrophysics Data System (ADS)

Mishra, Phoolendra Kumar; Vesselinov, Velimir V.; Neuman, Shlomo P.

2012-07-01

SummaryDrawdowns generated by extracting water from large diameter (e.g. water supply) well are affected by wellbore storage. We present an analytical solution in Laplace transformed space for drawdown in a uniform anisotropic aquifer caused by withdrawing water at a constant rate from partially penetrating well with storage. The solution is back transformed into the time domain numerically. When the pumping well is fully penetrating our solution reduces to that of Papadopulos and Cooper (1967); Hantush (1964) when the pumping well has no wellbore storage; Theis (1935) when both conditions are fulfilled and Yang (2006) when the pumping well is partially penetrating, has finite radius but lacks storage. Newly developed solution is then used to explore graphically the effects of partial penetration, wellbore storage and anisotropy on time evolutions of drawdown in the pumping well and in observation wells. We concluded after validating the developed analytical solution using synthetic pumping test.

Nanoparticles Penetrate into the Multicellular Spheroid-on-Chip: Effect of Surface Charge, Protein Corona, and Exterior Flow.

PubMed

Huang, Ke; Boerhan, Rena; Liu, Changming; Jiang, Guoqiang

2017-12-04

Nanoparticles (NPs) are widely studied as tumor targeted vehicles. The penetration of NPs into the tumor is considered as a major barrier for delivery of NPs into tumor cell and a big challenge to translate NPs from lab to the clinic. The objective of this study is to know how the surface charge of NPs, the protein corona surrounding the NPs, and the fluid flow around the tumor surface affect the penetration and accumulation of NPs into the tumor, through in vitro penetration study based on a spheroid-on-chip system. Surface decorated polystyrene (PS) NPs (100 nm) carrying positive and negative surface charge were loaded to the multicellular spheroids under static and flow conditions, in the presence or absence of serum proteins. NP penetration was investigated by confocal laser microscopy scanning followed with quantitative image analysis. The results reveal that negatively charged NPs are attached more on the spheroid surface and easier to penetrate into the spheroids. Protein corona, which is formed surrounding the NPs in the presence of serum protein, changes the surface properties of the NPs, weakens the NP-cell affinity, and, therefore, results in lower NP concentration on the spheroid surface but might facilitate deeper penetration. The exterior fluid flow enhances the interstitial flow into the spheroid, which benefits the penetration but also strips the NPs (especially the NPs with protein corona) on the spheroid surface, which decreases the penetration flux significantly. The maximal penetration was obtained by applying negatively charged NPs without protein corona under the flow condition. We hope the present study will help to understand the spatiotemporal performance of drug delivery NPs and inform the rational design of NPs with highly defined drug accumulation localized at a target site.

[The aspiratory resistance and filtration penetration of N95 filtering-facepiece respirators used widely in China].

PubMed

Wang, Xinyan; Shi, Tingming; Lu, Wei; Qin, Shaoxian; Liu, Yuewei; Tao, Ying; Zhang, Hongge; Chen, Weihong

2015-01-01

The objective of this study was to investigate the aspiratory resistance, filtration penetration and their influence factors of N95 filtering-facepiece respirators used widely in China. The total of 6 brands and 21 models of N95 filtering-facepiece respirators which are certified and big sales on the market. The aspiratory resistance and filtration efficiency filter penetration were measured while air pump ran from 10 L/min to 100 L/min using differential pressure gauge and the PortaCount, respectively. The filtration penetrations for 2 of the 21 models were lower than 95%, and the qualified rate for all models was 90.47%. The filtration penetrations gradually decreased when ventilation flow of air pump increased. The negative correlation was observed between filtration penetration and ventilation flow (r(2) = 0.711, P < 0.05). The resistances of all 21 models of N95 respirators met the requirements of the national standard. The aspiratory resistance started to elevate with the increasing of ventilation flow, and a positive correlation between both (r(2) = 0.878, P < 0.05). Significant differences of filtration penetration and aspiratory resistance were observed among between different brands (P < 0.05) although no differences of filtration penetration existed among different models of one brand (P > 0.05). But the differences of the aspiratory resistance among different models of one brand were statistically significant (P < 0.05). The aspiratory resistances of all N95 filtering-facepiece respirators used in this study met the requirements of the national standard. And the qualified ratio of filtration penetration of all models was higher than 90%. The influencing factors of aspiratory resistance included materials, size and ventilation flow. And influencing factors for filtration penetration were materials and ventilation flow.

Sex Differences in Childhood Sexual Abuse Characteristics and Victims' Emotional and Behavioral Problems: Findings from a National Sample of Youth

ERIC Educational Resources Information Center

Maikovich-Fong, Andrea Kohn; Jaffee, Sara R.

2010-01-01

Objective: The first objective of this study was to test for sex differences in four childhood sexual abuse characteristics--penetration, substantiation, perpetrator familial status, and multi-maltreatment--in a national sample of youth. The second objective was to test for sex differences in how these abuse characteristics were associated with…

The Inland Penetration of Atmospheric Rivers over Western North America: A Lagrangian Analysis

NASA Astrophysics Data System (ADS)

Rutz, J. J.; Steenburgh, W. J.; Ralph, F. M.

2014-12-01

Although atmospheric rivers (ARs) typically weaken following landfall, those that penetrate inland can contribute to heavy precipitation and high-impact weather within the interior of western North America. In this paper, we examine the evolution of ARs over western North America using trajectories released at 950 and 700 hPa within cool-season ARs along the Pacific coast. These trajectories are classified as coastal decaying, inland penetrating, or interior penetrating based on whether they remain within an AR upon reaching selected transects over western North America. Interior-penetrating AR trajectories most frequently make landfall along the Oregon coast, but the greatest fraction of landfalling AR trajectories that eventually penetrate into the interior is found along the Baja Peninsula. In contrast, interior-penetrating trajectories rarely traverse the southern "high" Sierra. At landfall, interior-penetrating trajectories are associated with a more amplified flow pattern, more southwesterly (vs. westerly) flow along the Pacific coast, and larger water vapor transport (qu). The larger initial qu of interior-penetrating trajectories is due primarily to larger initial water vapor (q) and wind speed (u) for those initiated at 950 and 700 hPa, respectively. Inland- and interior-penetrating AR trajectories maintain large qu over the interior due partially to increases in u that offset decreases in q, particularly in the vicinity of topographical barriers. Therefore, synoptic conditions and trajectory pathways favoring larger initial qu at the coast, limited water vapor depletion by orographic precipitation, and increases in u over the interior are keys to differentiating interior-penetrating from coastal-decaying AR trajectories.

Modification of Salmonella Lipopolysaccharides Prevents the Outer Membrane Penetration of Novobiocin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nobre, Thatyane M.; Martynowycz, Michael W.; Andreev, Konstantin

Small hydrophilic antibiotics traverse the outer membrane of Gram-negative bacteria through porin channels. Large lipophilic agents traverse the outer membrane through its bilayer, containing a majority of lipopolysaccharides in its outer leaflet. Genes controlled by the two-component regulatory system PhoPQ modify lipopolysaccharides. We isolate lipopolysaccharides from isogenic mutants of Salmonella sp., one lacking the modification, the other fully modified. These lipopolysaccharides were reconstituted asmonolayers at the air-water interface, and their properties, aswell as their interaction with a large lipophilic drug, novobiocin, was studied. X-ray reflectivity showed that the drug penetrated the monolayer of the unmodified lipopolysaccharides reaching the hydrophobic region,butwasmore » prevented fromthis penetration intothemodified lipopolysaccharides.Results correlatewith behavior of bacterial cells, which become resistant to antibiotics after PhoPQ-regulated modifications. Grazing incidence x-ray diffraction showed that novobiocin produced a striking increase in crystalline coherence length, and the size of the near-crystalline domains.« less

A new measure of the impact of managed care on healthcare markets.

PubMed

Pawlson, L G; Moy, E M; Kim, J I; Griner, P F

2001-11-01

Most studies of managed care impact have used health maintenance organization (HMO) penetration or index of competition as the marker of managed care impact. However, little empirical evidence has been found to support the validity of these or other measures in current use. In addition, as managed care evolves to forms other than HMOs and managed care penetration in large metropolitan areas approaches 100% of commercially insured patients, the utility of the most commonly used measure, HMO penetration, will decrease still further. To provide a preliminary analysis of the use of premiums as a measure of market impact of managed care. Retrospective analysis (quartile, correlation, multiple-variable linear regression) of publicly available datasets. Labor market-adjusted HMO premiums from 3 publicly available sources, for the 56 largest metropolitan areas in the United States, were compared with penetration and index of competition as predictors of the dependent market variable, hospital bed-days per 1000 population. Health maintenance organization premiums in the Federal Employees Health Benefits Program emerged as the best predictor of HMO market impact. Average HMO premiums reported in the Interstudy database and for the Medicare+Choice program also outperformed penetration or index of competition in relating to several commonly available markers of competition such as bed-days per 1000. Premiums charged by HMOs are a useful measure of the impact of managed care on healthcare markets in large metropolitan areas.

Plasma response to m/n  =  3/1 resonant magnetic perturbation at J-TEXT Tokamak

NASA Astrophysics Data System (ADS)

Hu, Qiming; Li, Jianchao; Wang, Nengchao; Yu, Q.; Chen, Jie; Cheng, Zhifeng; Chen, Zhipeng; Ding, Yonghua; Jin, Hai; Li, Da; Li, Mao; Liu, Yang; Rao, Bo; Zhu, Lizhi; Zhuang, Ge; the J-TEXT Team

2016-09-01

The influence of resonant magnetic perturbations (RMPs) with a large m/n  =  3/1 component on electron density has been studied at J-TEXT tokamak by using externally applied static and rotating RMPs, where m and n are the poloidal and toroidal mode number, respectively. The detailed time evolution of electron density profile, measured by the polarimeter-interferometer, shows that the electron density n e first increases (decreases) inside (around/outside) of the 3/1 rational surface (RS), and it is increased globally later together with enhanced edge recycling. Associated with field penetration, the toroidal rotation around the 3/1 RS is accelerated in the co-I p direction and the poloidal rotation is changed from the electron to ion diamagnetic drift direction. Spontaneous unlocking-penetration circles occur after field penetration if the RMPs amplitude is not strong enough. For sufficiently strong RMPs, the 2/1 locked mode is also triggered due to mode coupling, and the global density is increased. The field penetration threshold is found to be linearly proportional to n eL (line-integrated density) at the 3/1 RS but to (n eL)0.73 for n e at the plasma core. In addition, for rotating RMPs with a large 3/1 component, field penetration causes a global increase in electron density.

Microorganism penetration in dentinal tubules of instrumented and retreated root canal walls. In vitro SEM study

PubMed Central

Al-Sulaiman, Alaa; Al-Rasheed, Fellwa; Alnajjar, Fatimah; Al-Abdulwahab, Bander; Al-Badah, Abdulhakeem

2014-01-01

Objectives This in vitro study aimed to investigate the ability of Candida albicans (C. albicans) and Enterococcus faecalis (E. faecalis) to penetrate dentinal tubules of instrumented and retreated root canal surface of split human teeth. Materials and Methods Sixty intact extracted human single-rooted teeth were divided into 4 groups, negative control, positive control without canal instrumentation, instrumented, and retreated. Root canals in the instrumented group were enlarged with endodontic instruments, while root canals in the retreated group were enlarged, filled, and then removed the canal filling materials. The teeth were split longitudinally after canal preparation in 3 groups except the negative control group. The teeth were inoculated with both microorganisms separately and in combination. Teeth specimens were examined by scanning electron microscopy (SEM), and the depth of penetration into the dentinal tubules was assessed using the SMILE view software (JEOL Ltd). Results Penetration of C. albicans and E. faecalis into the dentinal tubules was observed in all 3 groups, although penetration was partially restricted by dentin debris of tubules in the instrumented group and remnants of canal filling materials in the retreated group. In all 3 groups, E. faecalis penetrated deeper into the dentinal tubules by way of cell division than C. albicans which built colonies and penetrated by means of hyphae. Conclusions Microorganisms can easily penetrate dentinal tubules of root canals with different appearance based on the microorganism size and status of dentinal tubules. PMID:25383343

Costs and Clinical Quality Among Medicare Beneficiaries: Associations with Health Center Penetration of Low-Income Residents

PubMed Central

Sharma, Ravi; Lebrun-Harris, Lydie A.; Ngo-Metzger, Quyen

2014-01-01

Objective Determine the association between access to primary care by the underserved and Medicare spending and clinical quality across hospital referral regions (HRRs). Data Sources Data on elderly fee-for-service beneficiaries across 306 HRRs came from CMS’ Geographic Variation in Medicare Spending and Utilization database (2010). We merged data on number of health center patients (HRSA’s Uniform Data System) and number of low-income residents (American Community Survey). Study Design We estimated access to primary care in each HRR by “health center penetration” (health center patients as a proportion of low-income residents). We calculated total Medicare spending (adjusted for population size, local input prices, and health risk). We assessed clinical quality by preventable hospital admissions, hospital readmissions, and emergency department visits. We sorted HRRs by health center penetration rate and compared spending and quality measures between the high- and low-penetration deciles. We also employed linear regressions to estimate spending and quality measures as a function of health center penetration. Principal Findings The high-penetration decile had 9.7% lower Medicare spending ($926 per capita, p=0.01) than the low-penetration decile, and no different clinical quality outcomes. Conclusions Compared with elderly fee-for-service beneficiaries residing in areas with low-penetration of health center patients among low-income residents, those residing in high-penetration areas may accrue Medicare cost savings. Limited evidence suggests that these savings do not compromise clinical quality. PMID:25243096

Radiofrequency penetration and absorption in the human body: limitations to high-field whole-body nuclear magnetic resonance imaging.

PubMed

Röschmann, P

1987-01-01

This study presents experimental results about the effective depth of penetration and about the radiofrequency (rf) power absorption in humans as a function of frequency. The frequency range investigated covers 10 up to 220 MHz. For the main part, the results were derived from bench measurements of the quality factor Q, and of the resonance frequency shift due to the loading of the coil. Different types of head-, body-, and surface coils were investigated loaded with volunteers or metallic phantoms. For spin-echo imaging at 2 T (85 MHz), the local specific absorption rate (SAR) was found to be approximately equal to 0.05 W/kg using a pi pulse of 1-ms duration and pulse repetition time TR = 1 s. Measurements of the quality factor Q as a function of frequency show that the SAR depends upon the frequency f according to approximately f2.15. The effective depth of rf penetration as derived drops from 17 cm at 85 MHz to 7 cm at 220 MHz. Head imaging with B1 penetrating from practically all sides into the object should be possible up to 220 MHz (5 T) with SAR values staying within the local limit of 2 W/kg as set by the FDA. Whole-body imaging of large subjects as well as surface coil imaging is depth limited above 100-MHz frequency. Perturbation methods are applied in order to separate the total rf power deposition in the patient into dielectric and magnetic contributions. The observed effects due to interactions of rf magnetic fields with biological tissue contradict predictions based on homogeneous tissue models. A refined tissue model with regions of high electrical conductivity, subdivided by quasi-insulating adipose layers, provides a rationale for a better understanding of the underlying processes. At frequencies below 100 MHz, the rf power deposition in patients is apparently more evenly distributed over the exposed body volume than currently assumed.

Reconciling Consumer and Utility Objectives in the Residential Solar PV Market

NASA Astrophysics Data System (ADS)

Arnold, Michael R.

Today's energy market is facing large-scale changes that will affect all market players. Near the top of that list is the rapid deployment of residential solar photovoltaic (PV) systems. Yet that growing trend will be influenced multiple competing interests between various stakeholders, namely the utility, consumers and technology provides. This study provides a series of analyses---utility-side, consumer-side, and combined analyses---to understand and evaluate the effect of increases in residential solar PV market penetration. Three urban regions have been selected as study locations---Chicago, Phoenix, Seattle---with simulated load data and solar insolation data at each locality. Various time-of-use pricing schedules are investigated, and the effect of net metering is evaluated to determine the optimal capacity of solar PV and battery storage in a typical residential home. The net residential load profile is scaled to assess system-wide technical and economic figures of merit for the utility with an emphasis on intraday load profiles, ramp rates and electricity sales with increasing solar PV penetration. The combined analysis evaluates the least-cost solar PV system for the consumer and models the associated system-wide effects on the electric grid. Utility revenue was found to drop by 1.2% for every percent PV penetration increase, net metering on a monthly or annual basis improved the cost-effectiveness of solar PV but not battery storage, the removal of net metering policy and usage of an improved the cost-effectiveness of battery storage and increases in solar PV penetration reduced the system load factor. As expected, Phoenix had the most favorable economic scenario for residential solar PV, primarily due to high solar insolation. The study location---solar insolation and load profile---was also found to affect the time of year at which the largest net negative system load was realized.

The application of an MPM-MFM method for simulating weapon-target interaction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, X.; Zou, Q.; Zhang, D. Z.

2005-01-01

During the past two decades, Los Alamos National Laboratory (LANL) has developed computational algorithms and software for analysis of multiphase flow suitable for high-speed projectile penetration of metallic and nonmetallic materials, using a material point method (MPM)-multiphase flow method (MFM). Recently, ACTA has teamed with LANL to advance a computational algorithm for simulating complex weapon-target interaction for penetrating and exploding munitions, such as tank rounds and artillery shells, as well as non-exploding kinetic energy penetrators. This paper will outline the mathematical basis for the MPM-MFM method as implemented in LANL's CartaBlanca code. CartaBlanca, written entirely in Java using object-oriented design,more » is used to solve complex problems involving (a) failure and penetration of solids, (b) heat transfer, (c) phase change, (d) chemical reactions, and (e) multiphase flow. We will present its application to the penetration of a steel target by a tungsten cylinder and compare results with time-resolved experimental data published by Anderson, et. al., Int. J. Impact Engng., Vol. 16, No. 1, pp. 1-18, 1995.« less

Health maintenance organization penetration and the practice location choices of new physicians: a study of large metropolitan areas in the United States.

PubMed

Escarce, J J; Polsky, D; Wozniak, G D; Pauly, M V; Kletke, P R

1998-11-01

The rapid growth of health maintenance organizations is reshaping the practice opportunities available to physicians. The practice location decisions of new physicians provide a sensitive bellwether of these changes. This study assessed the effect of health maintenance organization penetration on practice location for physicians completing graduate medical education (GME). Conditional logit regression analysis was used to determine the effect of health maintenance organization penetration on practice location, controlling for other market characteristics. Subjects were physicians who finished GME between 1989 and 1994 and who located in one of the 98 US metropolitan areas with more than 500,000 population. The outcome measure was the particular metropolitan area chosen by each new physician. Early in the study period, new generalists were significantly more likely to locate in metropolitan areas with high health maintenance organization penetration than in low penetration areas, whereas new specialists' practice location choices were not associated with health maintenance organization penetration. The likelihood of choosing a high penetration relative to a low penetration area declined with time, however, for both generalists and specialists. Consequently, by the end of the study period, health maintenance organization penetration had a weak but significant negative effect on practice location for generalists and a strong negative influence on practice location for specialists. New generalists who completed graduate medical education between 1989 and 1994 were more likely than new specialists to locate in market areas with high health maintenance organization penetration; however, the proportions of both generalists and specialists who chose high penetration areas decreased during the study period. This finding may reflect reduced practice opportunities in high penetration areas relative to low penetration areas as health maintenance organizations' systems for controlling utilization began to yield results. Alternatively, new physicians may have become more hesitant to accept available positions in high penetration areas.

Pneumocranium secondary to halo vest pin penetration through an enlarged frontal sinus.

PubMed

Cheong, Min Lee; Chan, Chris Yin Wei; Saw, Lim Beng; Kwan, Mun Keong

2009-07-01

We present a case report of a patient with pneumocranium secondary to halo vest pin penetration and a review of literature. The objectives of this study are to report a rare complication of halo vest pin insertion and to discuss methods of prevention of this complication. Halo vest orthosis is a commonly used and well-tolerated upper cervical spinal stabilizing device. Reports of complications related to pin penetration is rare and from our review, there has been no reports of pneumocranium occurring from insertion of pins following standard anatomical landmarks. A 57-year-old male sustained a type 1 traumatic spondylolisthesis of C2/C3 following a motor vehicle accident. During application of the halo vest, penetration of the left anterior pin through the abnormally enlarged frontal sinus occurred. The patient developed headache, vomiting and CSF rhinorrhoea over his left nostril. He was treated with intravenous Ceftriaxone for 1 week. This resulted in resolution of his symptoms as well as the pneumocranium. In conclusion, complications of halo vest pin penetration are rare and need immediate recognition. Despite the use of anatomical landmarks, pin penetration is still possible due to aberrant anatomy. All patients should have a skull X-ray with a radio-opaque marker done prior to placement of the halo vest pins and halo vest pins have to be inserted by experienced personnel to enable early detection of pin penetration.

The Impact Hazard

NASA Technical Reports Server (NTRS)

Morrison, David

1994-01-01

The Earth has been subject to hypervelocity impacts from comets and asteroids since its formation, and such impacts have played an important role in the evolution of life on our planet. We now recognize not only the historical role of impacts, but the contemporary hazard posed by such events. In the absence of a complete census of potentially threatening Earth-crossing asteroids or comets (called collectively Near Earth Objects, or NEOs), or even of a comprehensive cur-rent search program to identify NEOs, we can consider the hazard only from a probabilistic perspective. We know the steep power-law relationship between NEO numbers and size, with many more small bodies than large ones. We also know that few objects less than about 50 m in diameter (with kinetic energy near 10 megatons) penetrate the atmosphere and are capable of doing surface damage. But there is a spectrum of possible impact hazards associated with objects from this 10-megaton threshold all the way up to NEOs 5 km or larger in diameter, which are capable of inflicting severe damage on the environment, leading to mass extinction's of species. Detailed analysis has shown that, in general, the larger the object the greater the hazard, even when allowance is made for the infrequency of large impacts. Most of the danger to human life is associated with impacts by objects roughly 2 km or larger (energy greater than 1 million megatons), which can inject sufficient submicrometer dust into the atmosphere to produce a severe short-term global cooling with subsequent loss of crops, leading to starvation. Hazard estimates suggest that the chance of such an event occurring during a human lifetime is about 1:5000, and the global probability of death from such impacts is of the order of 1:20000, values that can be compared with risks associated with other natural hazards such as earthquakes, volcanic eruptions, and severe storms. However, the impact hazard differs from the others in that it can be largely prevented by a comprehensive survey for threatening objects and the application of technological solutions to deflect or destroy objects that are found to have orbits that will lead to collision with the Earth.

Exploration for fossil and nuclear fuels from orbital altitudes

NASA Technical Reports Server (NTRS)

Short, N. M.

1975-01-01

A review of satellite-based photographic (optical and infrared) and microwave exploration and large-area mapping of the earth's surface in the ERTS program. Synoptic cloud-free coverage of large areas has been achieved with planimetric vertical views of the earth's surface useful in compiling close-to-orthographic mosaics. Radar penetration of cloud cover and infrared penetration of forest cover have been successful to some extent. Geological applications include map editing (with corrections in scale and computer processing of images), landforms analysis, structural geology studies, lithological identification, and exploration for minerals and fuels. Limitations of the method are noted.

Role of Concentrating Solar Power in Integrating Solar and Wind Energy: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denholm, P.; Mehos, M.

2015-06-03

As wind and solar photovoltaics (PV) increase in penetration it is increasingly important to examine enabling technologies that can help integrate these resources at large scale. Concentrating solar power (CSP) when deployed with thermal energy storage (TES) can provide multiple services that can help integrate variable generation (VG) resources such as wind and PV. CSP with TES can provide firm, highly flexible capacity, reducing minimum generation constraints which limit penetration and results in curtailment. By acting as an enabling technology, CSP can complement PV and wind, substantially increasing their penetration in locations with adequate solar resource.

How soft is that pillow? The perceptual localization of the hand and the haptic assessment of contact rigidity.

PubMed

Pressman, Assaf; Karniel, Amir; Mussa-Ivaldi, Ferdinando A

2011-04-27

A new haptic illusion is described, in which the location of the mobile object affects the perception of its rigidity. There is theoretical and experimental support for the notion that limb position sense results from the brain combining ongoing sensory information with expectations arising from prior experience. How does this probabilistic state information affect one's tactile perception of the environment mechanics? In a simple estimation process, human subjects were asked to report the relative rigidity of two simulated virtual objects. One of the objects remained fixed in space and had various coefficients of stiffness. The other virtual object had constant stiffness but moved with respect to the subjects. Earlier work suggested that the perception of an object's rigidity is consistent with a process of regression between the contact force and the perceived amount of penetration inside the object's boundary. The amount of penetration perceived by the subject was affected by varying the position of the object. This, in turn, had a predictable effect on the perceived rigidity of the contact. Subjects' reports on the relative rigidity of the object are best accounted for by a probabilistic model in which the perceived boundary of the object is estimated based on its current location and on past observations. Therefore, the perception of contact rigidity is accounted for by a stochastic process of state estimation underlying proprioceptive localization of the hand.

A Study of TRMM Static Earth Sensor Performance Using On-Orbit Sensor Data

NASA Technical Reports Server (NTRS)

Natanson, Gregory; Glickman, Jonathan

2000-01-01

This paper presents the results of a study of the Barnes static Earth sensor assembly (ESA) using on-orbit data collected from the Tropical Rainfall Measuring Mission (TRMM) spacecraft. It is shown that there exist strong correlations between the large penetration angle residuals and the voltages produced by the Offset Radiation Source (ORS). It is conjectured that at certain times in the TRMM orbit the ORS is operating out of its calibrated range, and consequently corrupts the penetration angle information observed and processed by the ESA. The observed yaw drift between Digital Sun Sensor (DSS) observations is shown to be consistent with predictions by a simple roll-yaw coupling computation. This would explain the large drifts seen on TRMM, where the propagation of the yaw angle between DSS updates does not take into account the possibility of a non-zero roll angle error. Finally, the accuracy of the onboard algorithm used when only three of the four quadrants supply valid penetration angles is assessed. In terms of procedures used to perform this study, the analysis of ESA penetration angle residuals is discovered to be a very useful and insightful tool for assessing, the health and functionality of the ESA.

Multi-Mounted X-Ray Computed Tomography

PubMed Central

Fu, Jian; Liu, Zhenzhong; Wang, Jingzheng

2016-01-01

Most existing X-ray computed tomography (CT) techniques work in single-mounted mode and need to scan the inspected objects one by one. It is time-consuming and not acceptable for the inspection in a large scale. In this paper, we report a multi-mounted CT method and its first engineering implementation. It consists of a multi-mounted scanning geometry and the corresponding algebraic iterative reconstruction algorithm. This approach permits the CT rotation scanning of multiple objects simultaneously without the increase of penetration thickness and the signal crosstalk. Compared with the conventional single-mounted methods, it has the potential to improve the imaging efficiency and suppress the artifacts from the beam hardening and the scatter. This work comprises a numerical study of the method and its experimental verification using a dataset measured with a developed multi-mounted X-ray CT prototype system. We believe that this technique is of particular interest for pushing the engineering applications of X-ray CT. PMID:27073911

Investigation of molecular penetration depth variation with SMBI fluxes

NASA Astrophysics Data System (ADS)

Zhou, Yu-Lin; Wang, Zhan-Hui; Xu, Min; Wang, Qi; Nie, Lin; Feng, Hao; Sun, Wei-Guo

2016-09-01

We study the molecular penetration depth variation with the SMBI fluxes. The molecular transport process and the penetration depth during SMBI with various injection velocities and densities are simulated and compared. It is found that the penetration depth of molecules strongly depends on the radial convective transport of SMBI and it increases with the increase of the injection velocity. The penetration depth does not vary much once the SMBI injection density is larger than a critical value due to the dramatic increase of the dissociation rate on the fueling path. An effective way to improve the SMBI penetration depth has been predicted, which is SMBI with a large radial injection velocity and a lower molecule injection density than the critical density. Project supported by the National Natural Science Foundation of China (Grant Nos. 11375053, 11575055, 11405022, and 11405112), the Chinese National Fusion Project for ITER (Grant Nos. 2013GB107001 and 2013GB112005), the International S&T Cooperation Program of China (Grant No. 2015DFA61760), and the Funds of the Youth Innovation Team of Science and Technology in Sichuan Province of China (Grant No. 2014TD0023).

Convection Cells in the Atmospheric Boundary Layer

NASA Astrophysics Data System (ADS)

Fodor, Katherine; Mellado, Juan-Pedro

2017-04-01

In dry, shear-free convective boundary layers (CBLs), the turbulent flow of air is known to organise itself on large scales into coherent, cellular patterns, or superstructures, consisting of fast, narrow updraughts and slow, wide downdraughts which together form circulations. Superstructures act as transport mechanisms from the surface to the top of the boundary layer and vice-versa, as opposed to small-scale turbulence, which only modifies conditions locally. This suggests that a thorough investigation into superstructure properties may help us better understand transport across the atmospheric boundary layer as a whole. Whilst their existence has been noted, detailed studies into superstructures in the CBL have been scarce. By applying methods which are known to successfully isolate similar large-scale patterns in turbulent Rayleigh-Bénard convection, we can assess the efficacy of those detection techniques in the CBL. In addition, through non-dimensional analysis, we can systematically compare superstructures in various convective regimes. We use direct numerical simulation of four different cases for intercomparison: Rayleigh-Bénard convection (steady), Rayleigh-Bénard convection with an adiabatic top lid (quasi-steady), a stably-stratified CBL (quasi-steady) and a neutrally-stratified CBL (unsteady). The first two are non-penetrative and the latter two penetrative. We find that although superstructures clearly emerge from the time-mean flow in the non-penetrative cases, they become obscured by temporal averaging in the CBL. This is because a rigid lid acts to direct the flow into counter-rotating circulation cells whose axis of rotation remains stationary, whereas a boundary layer that grows in time and is able to entrain fluid from above causes the circulations to not only grow in vertical extent, but also to move horizontally and merge with neighbouring circulations. Spatial filtering is a useful comparative technique as it can be performed on boundary layers of the same depth, defined from the surface to the height at which the turbulent kinetic energy (TKE) is zero (in non-penetrative cases) or less than 10% of its maximum value (in penetrative cases). We find that with increasing filter width, the contribution of the filtered flow to the total TKE in the middle of the boundary layer decreases much more rapidly in the penetrative cases than in the non-penetrative cases. In particular, around 20-25% of the TKE at this height comes from small-scale turbulence with a length scale less than or equal to 15% of the boundary layer depth in the CBL, whereas in Rayleigh-Bénard convection, it is just 6-7%. This is consistent with visualisations, which show that entrainment creates additional small-scale mixing within the large-scale circulations in the CBL. Without entrainment, large-scale organisation predominates. Neither spatial nor temporal filtering are as successful at extracting superstructures in the penetrative cases as in the non-penetrative cases. Hence, these techniques depend not on the steadiness of the system, but rather on the presence of entrainment. We therefore intend to try other detection techniques, such as proper orthogonal decomposition, in order to make a rigorous assessment of which is most effective for isolating superstructures in all four cases.

Impact of High PV Penetration on the Inter-Area Oscillations in the U.S. Eastern Interconnection

DOE PAGES

You, Shutang; Kou, Gefei; Liu, Yong; ...

2017-03-31

Our study explores the impact of high-photovoltaic (PV) penetration on the inter-area oscillation modes of large-scale power grids. A series of dynamic models with various PV penetration levels are developed based on a detailed model representing the U.S. Eastern Interconnection (EI). Transient simulations are performed to investigate the change of inter-area oscillation modes with PV penetration. The impact of PV control strategies and parameter settings on inter-area oscillations is studied. This paper finds that as PV increases, the damping of the dominant oscillation mode decreases monotonically. We also observed that the mode shape varies with the PV control strategy andmore » new oscillation modes may emerge under inappropriate parameter settings in PV plant controls.« less

An Experimental Study of Dependence of Optimum TBM Cutter Spacing on Pre-set Penetration Depth in Sandstone Fragmentation

NASA Astrophysics Data System (ADS)

Han, D. Y.; Cao, P.; Liu, J.; Zhu, J. B.

2017-12-01

Cutter spacing is an essential parameter in the TBM design. However, few efforts have been made to study the optimum cutter spacing incorporating penetration depth. To investigate the influence of pre-set penetration depth and cutter spacing on sandstone breakage and TBM performance, a series of sequential laboratory indentation tests were performed in a biaxial compression state. Effects of parameters including penetration force, penetration depth, chip mass, chip size distribution, groove volume, specific energy and maximum angle of lateral crack were investigated. Results show that the total mass of chips, the groove volume and the observed optimum cutter spacing increase with increasing pre-set penetration depth. It is also found that the total mass of chips could be an alternative means to determine optimum cutter spacing. In addition, analysis of chip size distribution suggests that the mass of large chips is dominated by both cutter spacing and pre-set penetration depth. After fractal dimension analysis, we found that cutter spacing and pre-set penetration depth have negligible influence on the formation of small chips and that small chips are formed due to squeezing of cutters and surface abrasion caused by shear failure. Analysis on specific energy indicates that the observed optimum spacing/penetration ratio is 10 for the sandstone, at which, the specific energy and the maximum angle of lateral cracks are smallest. The findings in this paper contribute to better understanding of the coupled effect of cutter spacing and pre-set penetration depth on TBM performance and rock breakage, and provide some guidelines for cutter arrangement.

Validation of a measuring technique with computed tomography for cement penetration into trabecular bone underneath the tibial tray in total knee arthroplasty on a cadaver model

PubMed Central

2014-01-01

Background In total knee arthroplasty (TKA), cement penetration between 3 and 5 mm beneath the tibial tray is required to prevent loosening of the tibia component. The objective of this study was to develop and validate a reliable in vivo measuring technique using CT imaging to assess cement distribution and penetration depth in the total area underneath a tibia prosthesis. Methods We defined the radiodensity ranges for trabecular tibia bone, polymethylmethacrylate (PMMA) cement and cement-penetrated trabecular bone and measured the percentages of cement penetration at various depths after cementing two tibia prostheses onto redundant femoral heads. One prosthesis was subsequently removed to examine the influence of the metal tibia prostheses on the quality of the CT images. The percentages of cement penetration in the CT slices were compared with percentages measured with photographs of the corresponding transversal slices. Results Trabecular bone and cement-penetrated trabecular bone had no overlap in quantitative scale of radio-density. There was no significant difference in mean HU values when measuring with or without the tibia prosthesis. The percentages of measured cement-penetrated trabecular bone in the CT slices of the specimen were within the range of percentages that could be expected based on the measurements with the photographs (p = 0.04). Conclusions CT scan images provide valid results in measuring the penetration and distribution of cement into trabecular bone underneath the tibia component of a TKA. Since the proposed method does not turn metal elements into artefacts, it enables clinicians to assess the width and density of the cement mantle in vivo and to compare the results of different cementing methods in TKA. PMID:25158996

Effect of photodynamic therapy and non-thermal plasma on root canal filling: analysis of adhesion and sealer penetration

PubMed Central

MENEZES, Marilia; PRADO, Maíra; GOMES, Brenda; GUSMAN, Heloisa; SIMÃO, Renata

2017-01-01

Abstract Objective The aim of this study was to evaluate the effect of photodynamic therapy (PDT) and non-thermal plasma (NTP) on adhesion and sealer penetration in root canals. Material and Methods Sixty single-rooted premolars were used. The teeth were prepared using a crown-down technique. NaOCl and EDTA were used for irrigation and smear layer removal, respectively. The root canals were divided into three groups: control, PDT, and NTP. After treatments, the roots were filled using gutta-percha and either AH Plus (AHP) or MTA Fillapex (MTAF) sealers. Samples were sectioned at 4, 8, and 12 mm from the apex (1-mm slices)and analyzed by the push-out bond strength test (adhesion) and confocal laser scanning microscopy (sealer penetration). Data were statistically evaluated using Kruskal-Wallis, Dunn’s, and Spearman’s tests. Results Regarding AHP, bond strength was similar in the NTP group and in the control group, but significantly lower in the PDT group. As to MTAF, both therapies showed lower values than the control group. In the confocal analysis of AHP, maximum and mean penetration, and penetrated area were statistically higher in the control group than in the PDT and NTP groups. Penetrated perimeter was similar among groups. Regarding MTAF, all parameters yielded better results in the NTP than in the control group. The PDT and control groups showed similar results except for penetrated area. Conclusion PDT and plasma therapy affected the adhesion and sealer penetration of root canals filled with AH Plus and MTA Fillapex and there is no positive correlation between adhesion and sealer penetration. PMID:28877278

Search algorithm complexity modeling with application to image alignment and matching

NASA Astrophysics Data System (ADS)

DelMarco, Stephen

2014-05-01

Search algorithm complexity modeling, in the form of penetration rate estimation, provides a useful way to estimate search efficiency in application domains which involve searching over a hypothesis space of reference templates or models, as in model-based object recognition, automatic target recognition, and biometric recognition. The penetration rate quantifies the expected portion of the database that must be searched, and is useful for estimating search algorithm computational requirements. In this paper we perform mathematical modeling to derive general equations for penetration rate estimates that are applicable to a wide range of recognition problems. We extend previous penetration rate analyses to use more general probabilistic modeling assumptions. In particular we provide penetration rate equations within the framework of a model-based image alignment application domain in which a prioritized hierarchical grid search is used to rank subspace bins based on matching probability. We derive general equations, and provide special cases based on simplifying assumptions. We show how previously-derived penetration rate equations are special cases of the general formulation. We apply the analysis to model-based logo image alignment in which a hierarchical grid search is used over a geometric misalignment transform hypothesis space. We present numerical results validating the modeling assumptions and derived formulation.

Skin penetration surrogate for the evaluation of less lethal kinetic energy munitions.

PubMed

Bir, Cynthia A; Resslar, Marianne; Stewart, Shelby

2012-07-10

Although the benefits of the use of less lethal kinetic energy munitions are numerous, there is a need to evaluate the munitions prior to deployment to ensure their intended effect. The objective of the current research was to validate a surrogate that could be used to predict the risk of penetration of these devices. Existing data from biomechanical testing with post-mortem human specimens (PMHS) served as the foundation for this research. Development of the surrogate involved simulating the various layers of the skin and underlying soft tissues using a combination of materials. A standardized 12-gauge impactor was used to assess each combination. The energy density that resulted in a 50% risk of penetration for the anterior thorax region (23.99 J/cm(2)) from the previous research was matched using a specific combination of layers. Twelve various combinations of materials were tested with the 50% risk of penetration determined. The final validated surrogate consisted of a Laceration Assessment Layer (LAL) of natural chamois and .6 cm of closed-cell foam over a Penetration Assessment Layer (PAL) of 20% ordnance gelatin. This surrogate predicted a 50% risk of penetration at 23.88 J/cm(2). Injury risk curves for the PMHS and surrogate development work are presented. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Amperometric monitoring of quercetin permeation through skin membranes.

PubMed

Rembiesa, Jadwiga; Gari, Hala; Engblom, Johan; Ruzgas, Tautgirdas

2015-12-30

Transdermal delivery of quercetin (QR, 3,3',4',5,7-pentahydroxyflavone), a natural flavonoid with a considerable antioxidant capacity, is important for medical treatment of, e.g., skin disorders. QR permeability through skin is low, which, at the same time, makes the monitoring of percutaneous QR penetration difficult. The objective of this study was to assess an electrochemical method for monitoring QR penetration through skin membranes. An electrode was covered with the membrane, exposed to QR solution, and electrode current was measured. The registered current was due to electro-oxidation of QR penetrating the membrane. Exploiting strict current-QR flux relationships diffusion coefficient, D, of QR in skin and dialysis membranes was calculated. The D values were strongly dependent on the theoretical model and parameters assumed in the processing of the amperometric data. The highest values of D were in the range of 1.6-6.1×10(-7)cm(2)/s. This was reached only for skin membranes pretreated with buffer-ethanol mixture for more than 24h. QR solutions containing penetration enhancers, ethanol and l-menthol, definitely increased D values. The results demonstrate that electrochemical setup gives a possibility to assess penetration characteristics as well as enables monitoring of penetration dynamics, which is more difficult by traditional methods using Franz cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Unsteady penetration of a target by a liquid jet

PubMed Central

Uth, Tobias; Deshpande, Vikram S.

2013-01-01

It is widely acknowledged that ceramic armor experiences an unsteady penetration response: an impacting projectile may erode on the surface of a ceramic target without substantial penetration for a significant amount of time and then suddenly start to penetrate the target. Although known for more than four decades, this phenomenon, commonly referred to as dwell, remains largely unexplained. Here, we use scaled analog experiments with a low-speed water jet and a soft, translucent target material to investigate dwell. The transient target response, in terms of depth of penetration and impact force, is captured using a high-speed camera in combination with a piezoelectric force sensor. We observe the phenomenon of dwell using a soft (noncracking) target material. The results show that the penetration rate increases when the flow of the impacting water jet is reversed due to the deformation of the jet–target interface––this reversal is also associated with an increase in the force exerted by the jet on the target. Creep penetration experiments with a constant indentation force did not show an increase in the penetration rate, confirming that flow reversal is the cause of the unsteady penetration rate. Our results suggest that dwell can occur in a ductile noncracking target due to flow reversal. This phenomenon of flow reversal is rather widespread and present in a wide range of impact situations, including water-jet cutting, needleless injection, and deposit removal via a fluid jet. PMID:24277818

Cognitive Penetration and Attention

PubMed Central

Gross, Steven

2017-01-01

Zenon Pylyshyn argues that cognitively driven attentional effects do not amount to cognitive penetration of early vision because such effects occur either before or after early vision. Critics object that in fact such effects occur at all levels of perceptual processing. We argue that Pylyshyn’s claim is correct—but not for the reason he emphasizes. Even if his critics are correct that attentional effects are not external to early vision, these effects do not satisfy Pylyshyn’s requirements that the effects be direct and exhibit semantic coherence. In addition, we distinguish our defense from those found in recent work by Raftopoulos and by Firestone and Scholl, argue that attention should not be assimilated to expectation, and discuss alternative characterizations of cognitive penetrability, advocating a kind of pluralism. PMID:28275358

Penetrating radiation: applications at Los Alamos National Laboratory

NASA Astrophysics Data System (ADS)

Watson, Scott; Hunter, James; Morris, Christopher

2013-09-01

Los Alamos has used penetrating radiography extensively throughout its history dating back to the Manhattan Project where imaging dense, imploding objects was the subject of intense interest. This interest continues today as major facilities like DARHT1 have become the mainstay of the US Stockpile Stewardship Program2 and the cornerstone of nuclear weapons certification. Meanwhile, emerging threats to national security from cargo containers and improvised explosive devices (IEDs) have invigorated inspection efforts using muon tomography, and compact x-ray radiography. Additionally, unusual environmental threats, like those from underwater oil spills and nuclear power plant accidents, have caused renewed interest in fielding radiography in severe operating conditions. We review the history of penetrating radiography at Los Alamos and survey technologies as presently applied to these important problems.

Linkage to D3S47 (C17) in one large autosomal dominant retinitis pigmentosa family and exclusion in another: confirmation of genetic heterogeneity.

PubMed Central

Lester, D H; Inglehearn, C F; Bashir, R; Ackford, H; Esakowitz, L; Jay, M; Bird, A C; Wright, A F; Papiha, S S; Bhattacharya, S S

1990-01-01

Recently Dryja and his co-workers observed a mutation in the 23d codon of the rhodopsin gene in a proportion of autosomal dominant retinitis pigmentosa (ADRP) patients. Linkage analysis with a rhodopsin-linked probe C17 (D3S47) was carried out in two large British ADRP families, one with diffuse-type (D-type) RP and the other with regional-type (R-type) RP. Significantly positive lod scores (lod score maximum [Zmax] = +5.58 at recombination fraction [theta] = .0) were obtained between C17 and our D-type ADRP family showing complete penetrance. Sequence and oligonucleotide analysis has, however, shown that no point mutation at the 23d codon exists in affected individuals in our complete-penetrance pedigree, indicating that another rhodopsin mutation is probably responsible for ADRP in this family. Significantly negative lod scores (Z less than -2 at theta = .045) were, however, obtained between C17 and our R-type family which showed incomplete penetrance. Previous results presented by this laboratory also showed no linkage between C17 and another large British R-type ADRP family with incomplete penetrance. This confirms genetic heterogeneity. Some types of ADRP are being caused by different mutations in the rhodopsin locus (3q21-24) or another tightly linked gene in this region, while other types of ADRP are the result of mutations elsewhere in the genome. Images Figure 2 Figure 3 Figure 4 PMID:2393026

Acoustic Emission Signals in Thin Plates Produced by Impact Damage

NASA Technical Reports Server (NTRS)

Prosser, William H.; Gorman, Michael R.; Humes, Donald H.

1999-01-01

Acoustic emission (AE) signals created by impact sources in thin aluminum and graphite/epoxy composite plates were analyzed. Two different impact velocity regimes were studied. Low-velocity (less than 0.21 km/s) impacts were created with an airgun firing spherical steel projectiles (4.5 mm diameter). High-velocity (1.8 to 7 km/s) impacts were generated with a two-stage light-gas gun firing small cylindrical nylon projectiles (1.5 mm diameter). Both the impact velocity and impact angle were varied. The impacts did not penetrate the aluminum plates at either low or high velocities. For high-velocity impacts in composites, there were both impacts that fully penetrated the plate as well as impacts that did not. All impacts generated very large amplitude AE signals (1-5 V at the sensor), which propagated as plate (extensional and/or flexural) modes. In the low-velocity impact studies, the signal was dominated by a large flexural mode with only a small extensional mode component detected. As the impact velocity was increased within the low velocity regime, the overall amplitudes of both the extensional and flexural modes increased. In addition, a relative increase in the amplitude of high-frequency components of the flexural mode was also observed. Signals caused by high-velocity impacts that did not penetrate the plate contained both a large extensional and flexural mode component of comparable amplitudes. The signals also contained components of much higher frequency and were easily differentiated from those caused by low-velocity impacts. An interesting phenomenon was observed in that the large flexural mode component, seen in every other case, was absent from the signal when the impact particle fully penetrated through the composite plates.

Huntington disease reduced penetrance alleles occur at high frequency in the general population

PubMed Central

Kay, Chris; Collins, Jennifer A.; Miedzybrodzka, Zosia; Madore, Steven J.; Gordon, Erynn S.; Gerry, Norman; Davidson, Mark; Slama, Ramy A.

2016-01-01

Objective: To directly estimate the frequency and penetrance of CAG repeat alleles associated with Huntington disease (HD) in the general population. Methods: CAG repeat length was evaluated in 7,315 individuals from 3 population-based cohorts from British Columbia, the United States, and Scotland. The frequency of ≥36 CAG alleles was assessed out of a total of 14,630 alleles. The general population frequency of reduced penetrance alleles (36–39 CAG) was compared to the prevalence of patients with HD with genetically confirmed 36–39 CAG from a multisource clinical ascertainment in British Columbia, Canada. The penetrance of 36–38 CAG repeat alleles for HD was estimated for individuals ≥65 years of age and compared against previously reported clinical penetrance estimates. Results: A total of 18 of 7,315 individuals had ≥36 CAG, revealing that approximately 1 in 400 individuals from the general population have an expanded CAG repeat associated with HD (0.246%). Individuals with CAG 36–37 genotypes are the most common (36, 0.096%; 37, 0.082%; 38, 0.027%; 39, 0.000%; ≥40, 0.041%). General population CAG 36–38 penetrance rates are lower than penetrance rates extrapolated from clinical cohorts. Conclusion: HD alleles with a CAG repeat length of 36–38 occur at high frequency in the general population. The infrequent diagnosis of HD at this CAG length is likely due to low penetrance. Another important contributing factor may be reduced ascertainment of HD in those of older age. PMID:27335115

Influence of the mole penetrator on measurements of heat flow in lunar subsurface layers

NASA Astrophysics Data System (ADS)

Wawrzaszek, Roman; Drogosz, Michal; Seweryn, Karol; Banaszkiewicz, Marek; Grygorczuk, Jerzy

Measuring the thermal gradient in subsurface layers is a basic method of determination the heat flux from the interior of a planetary body to its surface. In case of the Moon, such measurements complemented with the results of theoretical analysis and modeling can significantly improve our understanding of the thermal and geological evolution of the Moon. In practice, temperature gradient measurements are performed by at least two sensors located at different depths under the surface. These sensors will be attached to a penetrator [1] or to a cable pulled behind the penetrator. In both cases the object that carries the sensors, e.g. penetrator, perturb temperature measurements. In our study we analyze a case of two thermal sensors attached to the ends of 350mm long penetrator made of a composite material. In agreement with the studies of other authors we have found that the penetrator should be placed at the depth of 2-3 meters, where periodic changes of the temperature due to variation of solar flux at the surface are significantly smaller than the error of temperature measurement. The most important result of our analysis is to show how to deconvolve the real gradient of the temperature from the measurements perturbed by the penetrator body. In this way it will be possible to more accurately determine heat flux in the lunar regolith. [1] Grygorczuk J., Seweryn K., Wawrzaszek R., Banaszkiewicz M., Insertion of a Mole Pene-trator -Experimental Results, /39th Lunar and Planetary Science Conference /League City, Texas 2008

Validation of the CNS Penetration-Effectiveness Rank for Quantifying Antiretroviral Penetration Into the Central Nervous System

PubMed Central

Letendre, Scott; Marquie-Beck, Jennifer; Capparelli, Edmund; Best, Brookie; Clifford, David; Collier, Ann C.; Gelman, Benjamin B.; McArthur, Justin C.; McCutchan, J. Allen; Morgello, Susan; Simpson, David; Grant, Igor; Ellis, Ronald J.

2009-01-01

Objective To evaluate whether penetration of a combination regimen into the central nervous system (CNS), as estimated by the CNS Penetration-Effectiveness (CPE) rank, is associated with lower cerebrospinal fluid (CSF) viral load. Design Data were analyzed from 467 participants who were human immunodeficiency virus (HIV) seropositive and who reported antiretroviral (ARV) drug use. Individual ARV drugs were assigned a penetration rank of 0 (low), 0.5 (intermediate), or 1 (high) based on their chemical properties, concentrations in CSF, and/or effectiveness in the CNS in clinical studies. The CPE rank was calculated by summing the individual penetration ranks for each ARV in the regimen. Results The median CPE rank was 1.5 (interquartile range, 1–2). Lower CPE ranks correlated with higher CSF viral loads. Ranks less than 2 were associated with an 88% increase in the odds of detectable CSF viral load. In multivariate regression, lower CPE ranks were associated with detectable CSF viral loads even after adjusting for total number of ARV drugs, ARV drug adherence, plasma viral load, duration and type of the current regimen, and CD4 count. Conclusions Poorer penetration of ARV drugs into the CNS appears to allow continued HIV replication in the CNS as indicated by higher CSF HIV viral loads. Because inhibition of HIV replication in the CNS is probably critical in treating patients who have HIV-associated neurocognitive disorders, ARV treatment strategies that account for CNS penetration should be considered in consensus treatment guidelines and validated in clinical studies. PMID:18195140

Ultrasonic/Sonic Impacting Penetrators

NASA Technical Reports Server (NTRS)

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

2008-01-01

Ultrasonic/sonic impacting penetrators (USIPs) are recent additions to the series of apparatuses based on ultrasonic/sonic drill corers (USDCs). A USIP enables a rod probe to penetrate packed soil or another substance of similar consistency, without need to apply a large axial force that could result in buckling of the probe or in damage to some buried objects. USIPs were conceived for use in probing and analyzing soil to depths of tens of centimeters in the vicinity of buried barrels containing toxic waste, without causing rupture of the barrels. USIPs could also be used for other purposes, including, for example, searching for pipes, barrels, or other hard objects buried in soil; and detecting land mines. USDCs and other apparatuses based on USDCs have been described in numerous previous NASA Tech Briefs articles. The ones reported previously were designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. To recapitulate: A USDC can be characterized as a lightweight, low-power, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. As shown in the figure, a basic USDC includes a piezoelectric stack, a backing and a horn connected to the stack, a free mass (free in the sense that it can slide axially a short distance between the horn and the shoulder of tool bit), and a tool bit, i.e., probe for USIP. The piezoelectric stack is driven at the resonance frequency of the stack/horn/backing assembly to create ultrasonic vibrations that are mechanically amplified by the horn. To prevent fracture during operation, the piezoelectric stack is held in compression by a bolt. The bouncing of the free mass between the horn and the tool bit at sonic frequencies generates hammering actions to the bit that are more effective for drilling than is the microhammering action of ultrasonic vibrations in ordinary ultrasonic drills. The hammering actions are so effective that the axial force needed to make the tool bit advance into the material of interest is much smaller than in ordinary twist drilling, ultrasonic drilling, or ordinary steady pushing.

Effect of elevated CO2 on coarse-root biomass in Florida scrub detected by ground-penetrating radar

Treesearch

Daniel B. Stover; Frank P. Day; John R Butnor; Bert G. Drake

2007-01-01

Growth and distribution of coarse roots in time and space represent a gap in our understanding of belowground ecology. Large roots may play a critical role in carbon sequestration belowground. Using ground-penetrating radar (GPR), we quantified coarseroot biomass from an open-top chamber experiment in a scrub-oak ecosystem at Kennedy Space Center, Florida, USA. GPR...

Antibody tumor penetration

PubMed Central

Thurber, Greg M.; Schmidt, Michael M.; Wittrup, K. Dane

2009-01-01

Antibodies have proven to be effective agents in cancer imaging and therapy. One of the major challenges still facing the field is the heterogeneous distribution of these agents in tumors when administered systemically. Large regions of untargeted cells can therefore escape therapy and potentially select for more resistant cells. We present here a summary of theoretical and experimental approaches to analyze and improve antibody penetration in tumor tissue. PMID:18541331

Optimal Operation and Management for Smart Grid Subsumed High Penetration of Renewable Energy, Electric Vehicle, and Battery Energy Storage System

NASA Astrophysics Data System (ADS)

Shigenobu, Ryuto; Noorzad, Ahmad Samim; Muarapaz, Cirio; Yona, Atsushi; Senjyu, Tomonobu

2016-04-01

Distributed generators (DG) and renewable energy sources have been attracting special attention in distribution systems in all over the world. Renewable energies, such as photovoltaic (PV) and wind turbine generators are considered as green energy. However, a large amount of DG penetration causes voltage deviation beyond the statutory range and reverse power flow at interconnection points in the distribution system. If excessive voltage deviation occurs, consumer's electric devices might break and reverse power flow will also has a negative impact on the transmission system. Thus, mass interconnections of DGs has an adverse effect on both of the utility and the customer. Therefore, reactive power control method is proposed previous research by using inverters attached DGs for prevent voltage deviations. Moreover, battery energy storage system (BESS) is also proposed for resolve reverse power flow. In addition, it is possible to supply high quality power for managing DGs and BESSs. Therefore, this paper proposes a method to maintain voltage, active power, and reactive power flow at interconnection points by using cooperative controlled of PVs, house BESSs, EVs, large BESSs, and existing voltage control devices. This paper not only protect distribution system, but also attain distribution loss reduction and effectivity management of control devices. Therefore mentioned control objectives are formulated as an optimization problem that is solved by using the Particle Swarm Optimization (PSO) algorithm. Modified scheduling method is proposed in order to improve convergence probability of scheduling scheme. The effectiveness of the proposed method is verified by case studies results and by using numerical simulations in MATLAB®.

Large area full-field optical coherence tomography using white light source

NASA Astrophysics Data System (ADS)

Chang, Shoude; Mao, Youxin; Sherif, Sherif; Flueraru, Costel

2007-06-01

Optical coherence tomography (OCT) is an emerging technology for high-resolution cross-sectional imaging of 3D structures. Not only could OCT extract the internal features of an object, but it could acquire the 3D profile of an object as well. Hence it has huge potentials for industrial applications. Owing to non-scanning along the X-Y axis, full-field OCT could be the simplest and most economic imaging system, especially for applications where the speed is critical. For an OCT system, the performance and cost basically depends on the light source being used. The broader the source bandwidth, the finer of the depth resolution that could be reached; the more power of the source, the better signal-to-noise ratio and the deeper of penetration the system achieves. A typical SLD (Superluminescent Diode) light source has a bandwidth of 15 nm and 10 mW optical power at a price around 6,000. However, a Halogen bulb having 50W power and 200nm bandwidth only costs less than 10. The design and implementation of a large-area, full-field OCT system using Halogen white-light source is described in the paper. The experimental results obtained from 3D shaping and multiple-layer tomographies are also presented.

A comparison of robust principal component analysis techniques for buried object detection in downward looking GPR sensor data

NASA Astrophysics Data System (ADS)

Pinar, Anthony; Havens, Timothy C.; Rice, Joseph; Masarik, Matthew; Burns, Joseph; Thelen, Brian

2016-05-01

Explosive hazards are a deadly threat in modern conflicts; hence, detecting them before they cause injury or death is of paramount importance. One method of buried explosive hazard discovery relies on data collected from ground penetrating radar (GPR) sensors. Threat detection with downward looking GPR is challenging due to large returns from non-target objects and clutter. This leads to a large number of false alarms (FAs), and since the responses of clutter and targets can form very similar signatures, classifier design is not trivial. One approach to combat these issues uses robust principal component analysis (RPCA) to enhance target signatures while suppressing clutter and background responses, though there are many versions of RPCA. This work applies some of these RPCA techniques to GPR sensor data and evaluates their merit using the peak signal-to-clutter ratio (SCR) of the RPCA-processed B-scans. Experimental results on government furnished data show that while some of the RPCA methods yield similar results, there are indeed some methods that outperform others. Furthermore, we show that the computation time required by the different RPCA methods varies widely, and the selection of tuning parameters in the RPCA algorithms has a major effect on the peak SCR.

Process for the detection of micro-cracks

DOEpatents

Lapinski, Norman; Sather, Allen

1979-01-01

A process for the nondestructive testing of ceramic objects to detect the presence of defects and micro-cracks in the surface in which a solution of silver nitrate is applied to the surface of the object which penetrates into the surface defects, drying the object so that the silver nitrate remains in the defects, and preparing an X-ray radiograph whereby any defects and micro-cracks will appear in the radiograph.

Penetration of Large Scale Electric Field to Inner Magnetosphere

NASA Astrophysics Data System (ADS)

Chen, S. H.; Fok, M. C. H.; Sibeck, D. G.; Wygant, J. R.; Spence, H. E.; Larsen, B.; Reeves, G. D.; Funsten, H. O.

2015-12-01

The direct penetration of large scale global electric field to the inner magnetosphere is a critical element in controlling how the background thermal plasma populates within the radiation belts. These plasma populations provide the source of particles and free energy needed for the generation and growth of various plasma waves that, at critical points of resonances in time and phase space, can scatter or energize radiation belt particles to regulate the flux level of the relativistic electrons in the system. At high geomagnetic activity levels, the distribution of large scale electric fields serves as an important indicator of how prevalence of strong wave-particle interactions extend over local times and radial distances. To understand the complex relationship between the global electric fields and thermal plasmas, particularly due to the ionospheric dynamo and the magnetospheric convection effects, and their relations to the geomagnetic activities, we analyze the electric field and cold plasma measurements from Van Allen Probes over more than two years period and simulate a geomagnetic storm event using Coupled Inner Magnetosphere-Ionosphere Model (CIMI). Our statistical analysis of the measurements from Van Allan Probes and CIMI simulations of the March 17, 2013 storm event indicate that: (1) Global dawn-dusk electric field can penetrate the inner magnetosphere inside the inner belt below L~2. (2) Stronger convections occurred in the dusk and midnight sectors than those in the noon and dawn sectors. (3) Strong convections at multiple locations exist at all activity levels but more complex at higher activity levels. (4) At the high activity levels, strongest convections occur in the midnight sectors at larger distances from the Earth and in the dusk sector at closer distances. (5) Two plasma populations of distinct ion temperature isotropies divided at L-Shell ~2, indicating distinct heating mechanisms between inner and outer radiation belts. (6) CIMI simulations reveal alternating penetration and shielding electric fields during the main phase of the geomagnetic storm, indicating an impulsive nature of the large scale penetrating electric field in regulating the gain and loss of radiation belt particles. We will present the statistical analysis and simulations results.

Penetrating head injury from angle grinder: A cautionary tale.

PubMed

Senthilkumaran, S; Balamurgan, N; Arthanari, K; Thirumalaikolundusubramanian, P

2010-01-01

Penetrating cranial injury is a potentially life-threatening condition. Injuries resulting from the use of angle grinders are numerous and cause high-velocity penetrating cranial injuries. We present a series of two penetrating head injuries associated with improper use of angle grinder, which resulted in shattering of disc into high velocity missiles with reference to management and prevention. One of those hit on the forehead of the operator and the other on the occipital region of the co-worker at a distance of five meters. The pathophysiological consequence of penetrating head injuries depends on the kinetic energy and trajectory of the object. In the nearby healthcare center the impacted broken disc was removed without realising the consequences and the wound was packed. As the conscious level declined in both, they were referred. CT brain revealed fracture in skull and changes in the brain in both. Expeditious removal of the penetrating foreign body and focal debridement of the scalp, skull, dura, and involved parenchyma and Watertight dural closure were carried out. The most important thing is not to remove the impacted foreign body at the site of accident. Craniectomy around the foreign body, debridement and removal of foreign body without zigzag motion are needed. Removal should be done following original direction of projectile injury. The neurological sequelae following the non missile penetrating head injuries are determined by the severity and location of initial injury as well as the rapidity of the exploration and fastidious debridement.

An evidence based review of the assessment and management of penetrating neck trauma.

PubMed

Burgess, C A; Dale, O T; Almeyda, R; Corbridge, R J

2012-02-01

Although relatively uncommon, penetrating neck trauma has the potential for serious morbidity and an estimated mortality of up to 6%. The assessment and management of patients who have sustained a penetrating neck injury has historically been an issue surrounded by significant controversy. OBJECTIVES OF REVIEW: To assess recent evidence relating to the assessment and management of penetrating neck trauma, highlighting areas of controversy with an overall aim of formulating clinical guidelines according to a care pathway format. Structured, non-systematic review of recent medical literature. An electronic literature search was performed in May 2011. The Medline database was searched using the Medical Subject Headings terms 'neck injuries' and 'wounds, penetrating' in conjunction with the terms 'assessment' or 'management'. Embase was searched with the terms 'penetrating trauma' and 'neck injury', also in conjunction with the terms 'assessment' and 'management'. Results were limited to articles published in English from 1990 to the present day. Abstracts were reviewed by the first three authors to select full-text articles for further critical appraisal. The references and citation links of these articles were hand-searched to identify further articles of relevance. 147 relevant articles were identified by the electronic literature search, comprising case series, case reports and reviews. 33 were initially selected for further evaluation. Although controversy continues to surround the management of penetrating neck trauma, the role of selective non-operative management and the utility of CT angiography to investigate potential vascular injuries appears to be increasingly accepted. © 2011 Blackwell Publishing Ltd.

Review and status of sonic boom penetration into the ocean.

PubMed

Sparrow, Victor W

2002-01-01

Since the 1970 Sonic Boom Symposium, held at the ASA's 80th meeting in Houston, TX, substantial progress has been made in understanding the penetration of sonic booms into the ocean. The state of the art at that time was documented by J. C. Cook, T. Goforth, and R. K. Cook [J. Acoust. Soc. Am. 51, 729-741 (1972)]. Since then, additional experiments have been performed which corroborate Cook's and Sawyers' theory for sonic boom penetration into a flat ocean surface. In addition, computational simulations have validated that theory and extended the work to include arbitrarily shaped waveforms penetrating flat ocean surfaces. Further numerical studies have investigated realistic ocean surfaces including large-scale ocean swell. Research has also been performed on the effects of ocean inhomogeneities due to bubble plumes. This paper provides a brief overview of these developments.

The Effect of Arrow Mass and Shape on Penetration into a Target

NASA Astrophysics Data System (ADS)

Shyam, S.; Gurram, A.; Madireddy, S.

2016-12-01

We conducted an archery experiment in order to quantify how aerodynamic design impacted the depth of arrow impact. Research shows that the smaller the surface area of an object, the more easily it travels through the air and the deeper it penetrates a target (Benson 2014). Momentum also affects how far and fast the arrow will go and therefore, how deep it will penetrate into the target. Therefore, a combination of an arrow with greater momentum and better aerodynamics will help the arrow fly faster and penetrate the target deeper. Mass, velocity, momentum, acceleration, force, and drag are the factors that acted on our experiment and produced its results. We hypothesized that the arrow with a thin shaft and pointed arrowhead would penetrate deepest, as opposed to both arrows with no arrowheads or arrows with thick shafts and blunt arrowheads. We tested our hypothesis by having a well-trained archer shoot different types of arrows into a target. We used arrows with shaft lengths of 7 cm and 5.3 cm, coupled with either pointed, blunt, or no arrowhead. We measured the time to target and arrow penetration (in cm) to see which style reached the target the fastest and penetrated the deepest. The results demonstrated that arrows with thin shafts and pointed arrowheads penetrated our target the deepest, followed by arrows with thick shafts and blunt arrowheads. Arrows with thin shafts and blunt arrowheads came after, and arrows with thick shafts and pointed arrowheads came last in depth of penetration. The arrows with no arrowheads either barely penetrated the target, or bounced back. We were able to conclude that the thinner the shaft and the more pointed the arrowhead, the better the arrow cuts the air. This is because, according to the principles of aerodynamics, it creates less drag since the surface area is smaller. However, mass also plays an important role in force through momentum, which also significantly affected our results.

Status of VESAS: a fully-electronic microwave imaging radiometer system

NASA Astrophysics Data System (ADS)

Schreiber, Eric; Peichl, Markus; Suess, Helmut

2010-04-01

Present applications of microwave remote sensing systems cover a large variety. One utilisation of the frequency range from 1 - 300 GHz is the domain of security and reconnaissance. Examples are the observation of critical infrastructures or the performance of security checks on people in order to detect concealed weapons or explosives, both being frequent threats in our world of growing international terrorism. The imaging capability of concealed objects is one of the main advantages of microwave remote sensing, because of the penetration performance of electromagnetic waves through dielectric materials in this frequency domain. The main physical effects used in passive microwave sensing rely on the naturally generated thermal radiation and the physical properties of matter, the latter being surface characteristics, chemical and physical composition, and the temperature of the material. As a consequence it is possible to discriminate objects having different material characteristics like ceramic weapons or plastic explosives with respect to the human body. Considering the use of microwave imaging with respect to people scanning systems in airports, railway stations, or stadiums, it is advantageous that passively operating devices generate no exposure on the scanned objects like actively operating devices do. For frequently used security gateways it is additionally important to have a high through-put rate in order to minimize the queue time. Consequently fast imaging systems are necessary. In this regard the conceptual idea of a fully-electronic microwave imaging radiometer system is introduced. The two-dimensional scanning mechanism is divided into a frequency scan in one direction and the method of aperture synthesis in the other. The overall goal here is to design a low-cost, fully-electronic imaging system with a frame rate of around one second at Ka band. This frequency domain around a center frequency of 37 GHz offers a well-balanced compromise between the achievable spatial resolution for a given size, and the penetration depth of the electromagnetic wave, which are conflictive requirements.

Development and evaluation of transdermal organogels containing nicorandil.

PubMed

Madan, J R; Sagar, Banode; Chellappan, Dinesh K; Dua, Kamal

2013-01-01

The objective of the study was to formulate a transdermal product containing Nicorandil as a model drug, because it has been first drug of choice to treat angina and hypertension. A further objective was to reduce its side effects. The transdermal product was prepared using various synthetic and natural gelling agents such as Carbopol 934p, Carbopol 974p, HPMC K15M and HPMC K100M. Various penetration enhancers were incorporated to enhance the diffusion across the rat skin. A further objective was to formulate organogels and minimize the concentration of penetration enhancer to 50% of the concentration used in gels and yet to achieve the maximum drug release. The prepared formulations were evaluated for their physical appearance, viscosity, spreadability, drug content and freeze thaw cycle. Based on in vitro studies across rat skin and human cadaver skin it was concluded that Nicrorandil transdermal organogel formulation using HPMC K100M with 2% w/w Transcutol-P shows increase in cumulative diffusion of Nicorandil amongst all other formulations.

Jet Penetration into a Scaled Microfabricated Stirling Cycle Regenerator

NASA Technical Reports Server (NTRS)

Sun, Liyong; Simon, Terrence W.; Mantell, Susan; Ibrahim, Mournir; Gedeon, David; Tew, Roy

2008-01-01

The cooler and heater adjacent to the regenerator of a Stirling cycle engine have tubes or channels which form jets that pass into the regenerator while diffusing within the matrix. An inactive part of the matrix, beyond the cores of these jets, does not participate fully in the heat transfer between the flow of working fluid and the regenerator matrix material, weakening the regenerator s ability to exchange heat with the working fluid. The objective of the present program is to document this effect on the performance of the regenerator and to develop a model for generalizing the results. However, the small scales of actual Stirling regenerator matrices (on the order of tens of microns) make direct measurements of this effect very difficult. As a result, jet spreading within a regenerator matrix has not been characterized well and is poorly understood. Also, modeling is lacking experimental verification. To address this, a large-scale mockup of thirty times actual scale was constructed and operated under conditions that are dynamically similar to the engine operation. Jet penetration with round jets and slot jets into the microfabricated regenerator geometry are then measured by conventional means. The results are compared with those from a study of spreading of round jets within woven screen regenerator for further documentation of the comparative performance of the microfabricated regenerator geometry.

The Effects of HMO Penetration on Preventable Hospitalizations

PubMed Central

Zhan, Chunliu; Miller, Marlene R; Wong, Herbert; Meyer, Gregg S

2004-01-01

Objective To examine the effects of health maintenance organization (HMO) penetration on preventable hospitalizations. Data Source Hospital inpatient discharge abstracts for 932 urban counties in 22 states from the Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases (SID), hospital data from American Hospital Association (AHA) annual survey, and population characteristics and health care capacity data from Health Resources and Services Administration (HRSA) Area Resource File (ARF) for 1998. Methods Preventable hospitalizations due to 14 ambulatory care sensitive conditions were identified using the Agency for Healthcare Research and Quality (AHRQ) Prevention Quality Indicators. Multiple regressions were used to determine the association between preventable hospitalizations and HMO penetration while controlling for demographic and socioeconomic characteristics and health care capacity of the counties. Principal Findings A 10 percent increase in HMO penetration was associated with a 3.8 percent decrease in preventable hospitalizations (95 percent confidence interval, 2.0 percent–5.6 percent). Advanced age, female gender, poor health, poverty, more hospital beds, and fewer primary care physicians per capita were significantly associated with more preventable hospitalizations. Conclusions Our study suggests that HMO penetration has significant effects in reducing preventable hospitalizations due to some ambulatory care sensitive conditions. PMID:15032958

Vena Cava Filter Retrieval with Aorto-Iliac Arterial Strut Penetration.

PubMed

Holly, Brian P; Gaba, Ron C; Lessne, Mark L; Lewandowski, Robert J; Ryu, Robert K; Desai, Kush R; Sing, Ronald F

2018-05-03

To evaluate the safety and technical success of inferior vena cava (IVC) filter retrieval in the setting of aorto-iliac arterial strut penetration. IVC filter registries from six large United States IVC filter retrieval practices were retrospectively reviewed to identify patients who underwent IVC filter retrieval in the setting of filter strut penetration into the adjacent aorta or iliac artery. Patient demographics, implant duration, indication for placement, IVC filter type, retrieval technique and technical success, adverse events, and post procedural clinical outcomes were identified. Arterial penetration was determined based on pre-procedure CT imaging in all cases. The IVC filter retrieval technique used was at the discretion of the operating physician. Seventeen patients from six US centers who underwent retrieval of an IVC filter with at least one strut penetrating either the aorta or iliac artery were identified. Retrieval technical success rate was 100% (17/17), without any major adverse events. Post-retrieval follow-up ranging from 10 days to 2 years (mean 4.6 months) was available in 12/17 (71%) patients; no delayed adverse events were encountered. Findings from this series suggest that chronically indwelling IVC filters with aorto-iliac arterial strut penetration may be safely retrieved.

Porcelain-coated antenna for radio-frequency driven plasma source

DOEpatents

Leung, Ka-Ngo; Wells, Russell P.; Craven, Glen E.

1996-01-01

A new porcelain-enamel coated antenna creates a clean plasma for volume or surface-conversion ion sources. The porcelain-enamel coating is hard, electrically insulating, long lasting, non fragile, and resistant to puncture by high energy ions in the plasma. Plasma and ion production using the porcelain enamel coated antenna is uncontaminated with filament or extraneous metal ion because the porcelain does not evaporate and is not sputtered into the plasma during operation. Ion beams produced using the new porcelain-enamel coated antenna are useful in ion implantation, high energy accelerators, negative, positive, or neutral beam applications, fusion, and treatment of chemical or radioactive waste for disposal. For ion implantation, the appropriate species ion beam generated with the inventive antenna will penetrate large or small, irregularly shaped conducting objects with a narrow implantation profile.

A simulation study of detection of weapon of mass destruction based on radar

NASA Astrophysics Data System (ADS)

Sharifahmadian, E.; Choi, Y.; Latifi, S.

2013-05-01

Typical systems used for detection of Weapon of Mass Destruction (WMD) are based on sensing objects using gamma rays or neutrons. Nonetheless, depending on environmental conditions, current methods for detecting fissile materials have limited distance of effectiveness. Moreover, radiation related to gamma- rays can be easily shielded. Here, detecting concealed WMD from a distance is simulated and studied based on radar, especially WideBand (WB) technology. The WB-based method capitalizes on the fact that electromagnetic waves penetrate through different materials at different rates. While low-frequency waves can pass through objects more easily, high-frequency waves have a higher rate of absorption by objects, making the object recognition easier. Measuring the penetration depth allows one to identify the sensed material. During simulation, radar waves and propagation area including free space, and objects in the scene are modeled. In fact, each material is modeled as a layer with a certain thickness. At start of simulation, a modeled radar wave is radiated toward the layers. At the receiver side, based on the received signals from every layer, each layer can be identified. When an electromagnetic wave passes through an object, the wave's power will be subject to a certain level of attenuation depending of the object's characteristics. Simulation is performed using radar signals with different frequencies (ranges MHz-GHz) and powers to identify different layers.

Antibody tumor penetration: transport opposed by systemic and antigen-mediated clearance.

PubMed

Thurber, Greg M; Schmidt, Michael M; Wittrup, K Dane

2008-09-01

Antibodies have proven to be effective agents in cancer imaging and therapy. One of the major challenges still facing the field is the heterogeneous distribution of these agents in tumors when administered systemically. Large regions of untargeted cells can therefore escape therapy and potentially select for more resistant cells. We present here a summary of theoretical and experimental approaches to analyze and improve antibody penetration in tumor tissue.

The Value of Homemade Phantoms for Training Veterinary Students in the Ultrasonographic Detection of Radiolucent Foreign Bodies

ERIC Educational Resources Information Center

Mariano Beraldo, Carolina; Rondon Lopes, Érika; Hage, Raduan; Hage, Maria Cristina F. N. S.

2017-01-01

Ingested or penetrating foreign bodies are common in veterinary medicine. When they are radiolucent, these objects become a diagnostic challenge, but they can be investigated sonographically. However, successful object identification depends on the skill of the sonographer. Considering that these cases appear randomly during hospital routines, it…

Containment penetration elastomer seal leak rate tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bridges, T.L.

1987-07-01

Tests were performed on three elastomer seal designs commonly used for nuclear plant containment mechanical penetrations. The objective of this research project is to obtain an understanding of the integrity and leakage behavior of these seal designs under severe accident temperature and pressure conditions. The three designs tested and the seal materials used in the tests were: (1) double tongue-and-groove design with silicone rubber seals, (2) double-O-ring design with neoprene and ethylene-propylene (EPDM) seals, and (3) double gumdrop design with neoprene and EPDM seals. The effects of thermal aging and angular rotations of flange mating surfaces were determined. The testmore » results provide information required to characterize the leakage behavior of penetrations under severe accident conditions. 3 refs., 10 figs., 12 tabs.« less

High-Performance Modeling and Simulation of Anchoring in Granular Media for NEO Applications

NASA Technical Reports Server (NTRS)

Quadrelli, Marco B.; Jain, Abhinandan; Negrut, Dan; Mazhar, Hammad

2012-01-01

NASA is interested in designing a spacecraft capable of visiting a near-Earth object (NEO), performing experiments, and then returning safely. Certain periods of this mission would require the spacecraft to remain stationary relative to the NEO, in an environment characterized by very low gravity levels; such situations require an anchoring mechanism that is compact, easy to deploy, and upon mission completion, easy to remove. The design philosophy used in this task relies on the simulation capability of a high-performance multibody dynamics physics engine. On Earth, it is difficult to create low-gravity conditions, and testing in low-gravity environments, whether artificial or in space, can be costly and very difficult to achieve. Through simulation, the effect of gravity can be controlled with great accuracy, making it ideally suited to analyze the problem at hand. Using Chrono::Engine, a simulation pack age capable of utilizing massively parallel Graphic Processing Unit (GPU) hardware, several validation experiments were performed. Modeling of the regolith interaction has been carried out, after which the anchor penetration tests were performed and analyzed. The regolith was modeled by a granular medium composed of very large numbers of convex three-dimensional rigid bodies, subject to microgravity levels and interacting with each other with contact, friction, and cohesional forces. The multibody dynamics simulation approach used for simulating anchors penetrating a soil uses a differential variational inequality (DVI) methodology to solve the contact problem posed as a linear complementarity method (LCP). Implemented within a GPU processing environment, collision detection is greatly accelerated compared to traditional CPU (central processing unit)- based collision detection. Hence, systems of millions of particles interacting with complex dynamic systems can be efficiently analyzed, and design recommendations can be made in a much shorter time. The figure shows an example of this capability where the Brazil Nut problem is simulated: as the container full of granular material is vibrated, the large ball slowly moves upwards. This capability was expanded to account for anchors of different shapes and penetration velocities, interacting with granular soils.

Single-Beam Acoustic Trapping of Red Blood Cells and Polystyrene Microspheres in Flowing Red Blood Cell Saline and Plasma Suspensions.

PubMed

Liu, Hsiao-Chuan; Li, Ying; Chen, Ruimin; Jung, Hayong; Shung, K Kirk

2017-04-01

Single-beam acoustic tweezers (SBATs) represent a new technology for particle and cell trapping. The advantages of SBATs are their deep penetration into tissues, reduction of tissue damage and ease of application to in vivo studies. The use of these tools for applications in drug delivery in vivo must meet the following conditions: large penetration depth, strong trapping force and tissue safety. A reasonable penetration depth for SBATs in the development of in vivo applications was established in a previous study conducted in water with zero velocity. However, capturing objects in flowing fluid can provide more meaningful results. In this study, we investigated the capability of SBATs to trap red blood cells (RBCs) and polystyrene microspheres in flowing RBC suspensions. Two different types of RBC suspension were prepared in this work: an RBC phosphate-buffered saline (PBS) suspension and an RBC plasma suspension. The results indicated that SBATs successfully trapped RBCs and polystyrene microspheres in a flowing RBC PBS suspension with an average steady velocity of 1.6 cm/s in a 2-mm-diameter polyimide. Furthermore, SBATs were found able to trap RBCs in a flowing RBC PBS suspension at speeds as high as 7.9 cm/s in a polyimide tube, which is higher than the velocity in capillaries (0.03 cm/s) and approaches the velocity in arterioles and venules. Moreover, the results also indicated that polystyrene microspheres can be trapped in an RBC plasma suspension, where aggregation is observed. This work represents a step forward in using this tool in actual in vivo experimentation. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Severity-Adjusted Mortality in Trauma Patients Transported by Police

PubMed Central

Band, Roger A.; Salhi, Rama A.; Holena, Daniel N.; Powell, Elizabeth; Branas, Charles C.; Carr, Brendan G.

2018-01-01

Study objective Two decades ago, Philadelphia began allowing police transport of patients with penetrating trauma. We conduct a large, multiyear, citywide analysis of this policy. We examine the association between mode of out-of-hospital transport (police department versus emergency medical services [EMS]) and mortality among patients with penetrating trauma in Philadelphia. Methods This is a retrospective cohort study of trauma registry data. Patients who sustained any proximal penetrating trauma and presented to any Level I or II trauma center in Philadelphia between January 1, 2003, and December 31, 2007, were included. Analyses were conducted with logistic regression models and were adjusted for injury severity with the Trauma and Injury Severity Score and for case mix with a modified Charlson index. Results Four thousand one hundred twenty-two subjects were identified. Overall mortality was 27.4%. In unadjusted analyses, patients transported by police were more likely to die than patients transported by ambulance (29.8% versus 26.5%; OR 1.18; 95% confidence interval [CI] 1.00 to 1.39). In adjusted models, no significant difference was observed in overall mortality between the police department and EMS groups (odds ratio [OR] 0.78; 95% CI 0.61 to 1.01). In subgroup analysis, patients with severe injury (Injury Severity Score >15) (OR 0.73; 95% CI 0.59 to 0.90), patients with gunshot wounds (OR 0.70; 95% CI 0.53 to 0.94), and patients with stab wounds (OR 0.19; 95% CI 0.08 to 0.45) were more likely to survive if transported by police. Conclusion We found no significant overall difference in adjusted mortality between patients transported by the police department compared with EMS but found increased adjusted survival among 3 key subgroups of patients transported by police. This practice may augment traditional care. PMID:24387925

Improving the treatment of non-aqueous phase TCE in low permeability zones with permanganate.

PubMed

Chokejaroenrat, Chanat; Comfort, Steve; Sakulthaew, Chainarong; Dvorak, Bruce

2014-03-15

Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is a particularly challenging issue for injection-based remedial treatments. Our objective was to improve the sweeping efficiency of permanganate (MnO4(-)) into LPZs to treat high concentrations of TCE. This was accomplished by conducting transport experiments that quantified the penetration of various permanganate flooding solutions into a LPZ that was spiked with non-aqueous phase (14)C-TCE. The treatments we evaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilization aids that minimized MnO2 rind formation and (iii) a phase-transfer catalyst. In addition, we quantified the ability of these flooding solutions to improve TCE destruction under batch conditions by developing miniature LPZ cylinders that were spiked with (14)C-TCE. Transport experiments showed that MnO4(-) alone was inefficient in penetrating the LPZ and reacting with non-aqueous phase TCE, due to a distinct and large MnO2 rind that inhibited the TCE from further oxidant contact. By including xanthan with MnO4(-), the sweeping efficiency increased (90%) but rind formation was still evident. By including the stabilization aid, sodium hexametaphosphate (SHMP) with xanthan, permanganate penetrated 100% of the LPZ, no rind was observed, and the percentage of TCE oxidized increased. Batch experiments using LPZ cylinders allowed longer contact times between the flooding solutions and the DNAPL and results showed that SHMP+MnO4(-) improved TCE destruction by ∼16% over MnO4(-) alone (56.5% vs. 40.1%). These results support combining permanganate with SHMP or SHMP and xanthan as a means of treating high concentrations of TCE in low permeable zones. Copyright © 2014 Elsevier B.V. All rights reserved.

Performance of N95 FFRs Against Combustion and NaCl Aerosols in Dry and Moderately Humid Air: Manikin-based Study.

PubMed

Gao, Shuang; Kim, Jinyong; Yermakov, Michael; Elmashae, Yousef; He, Xinjian; Reponen, Tiina; Zhuang, Ziqing; Rengasamy, Samy; Grinshpun, Sergey A

2016-07-01

The first objective of this study was to evaluate the penetration of particles generated from combustion of plastic through National Institute for Occupational Safety and Health (NIOSH)-certified N95 filtering facepiece respirators (FFRs) using a manikin-based protocol and compare the data to the penetration of NaCl particles. The second objective was to investigate the effect of relative humidity (RH) on the filtration performance of N95 FFRs. Two NIOSH-certified N95 FFRs (A and B) were fully sealed on a manikin headform and challenged with particles generated by combustion of plastic and NaCl particles. The tests were performed using two cyclic flows [with mean inspiratory flow (MIF) rates = 30 and 85 l min(-1), representing human breathing under low and moderate workload conditions] and two RH levels (≈20 and ≈80%, representing dry and moderately humid air). The total and size-specific particle concentrations inside (C in) and outside (C out) of the respirators were measured with a condensation particle counter and an aerosol size spectrometer. The penetration values (C in/C out) were calculated after each test. The challenge aerosol, RH, MIF rate, and respirator type had significant (P < 0.05) effects on the performance of the manikin-sealed FFR. Its efficiency significantly decreased when the FFR was tested with plastic combustion particles compared to NaCl aerosols. For example, at RH ≈80% and MIF = 85 l min(-1), as much as 7.03 and 8.61% of combustion particles penetrated N95 respirators A and B, respectively. The plastic combustion particles and gaseous compounds generated by combustion likely degraded the electric charges on fibers, which increased the particle penetration. Increasing breathing flow rate or humidity increased the penetration (reduced the respirator efficiency) for all tested aerosols. The effect of particle size on the penetration varied depending on the challenge aerosol and respirator type. It was observed that the peak of the size distribution of combustion particles almost coincided with their most penetrating particle size, which was not the case for NaCl particles. This finding was utilized for the data interpretation. N95 FFRs have lower filter efficiency when challenged with contaminant particles generated by combustion, particularly when used under high humidity conditions compared to NaCl particles. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

A statistical experimental design approach to evaluate the influence of various penetration enhancers on transdermal drug delivery of buprenorphine.

PubMed

Taghizadeh, S Mojtaba; Moghimi-Ardakani, Ali; Mohamadnia, Fatemeh

2015-03-01

A series of drug-in-adhesive transdermal drug delivery systems (patch) with different chemical penetration enhancers were designed to deliver drug through the skin as a site of application. The objective of our effort was to study the influence of various chemical penetration enhancers on skin permeation rate and adhesion properties of a transdermal drug delivery system using Box-Behnken experimental design. The response surface methodology based on a three-level, three-variable Box-Behnken design was used to evaluate the interactive effects on dependent variables including, the rate of skin permeation and adhesion properties, namely peel strength and tack value. Levulinic acid, lauryl alcohol, and Tween 80 were used as penetration enhancers (patch formulations, containing 0-8% of each chemical penetration enhancer). Buprenorphine was used as a model penetrant drug. The results showed that incorporation of 20% chemical penetration enhancer into the mixture led to maximum skin permeation flux of buprenorphine from abdominal rat skin while the adhesion properties decreased. Also that skin flux in presence of levulinic acid (1.594 μg/cm(2) h) was higher than Tween 80 (1.473 μg/cm(2) h) and lauryl alcohol (0.843 μg/cm(2) h), and in mixing these enhancers together, an additional effect was observed. Moreover, it was found that each enhancer increased the tack value, while levulinic acid and lauryl alcohol improved the peel strength but Tween 80 reduced it. These findings indicated that the best chemical skin penetration enhancer for buprenorphine patch was levulinic acid. Among the designed formulations, the one which contained 12% (wt/wt) enhancers exhibited the highest efficiency.

Penetrator role in Mars sample strategy

NASA Technical Reports Server (NTRS)

Boynton, William; Dwornik, Steve; Eckstrom, William; Roalstad, David A.

1988-01-01

The application of the penetrator to a Mars Return Sample Mission (MRSM) has direct advantages to meet science objectives and mission safety. Based on engineering data and work currently conducted at Ball Aerospace Systems Division, the concept of penetrators as scientific instruments is entirely practical. The primary utilization of a penetrator for MRSM would be to optimize the selection of the sample site location and to help in selection of the actual sample to be returned to Earth. It is recognized that the amount of sample to be returned is very limited, therefore the selection of the sample site is critical to the success of the mission. The following mission scenario is proposed. The site selection of a sample to be acquired will be performed by science working groups. A decision will be reached and a set of target priorities established based on data to give geochemical, geophysical and geological information. The first task of a penetrator will be to collect data at up to 4 to 6 possible landing sites. The penetrator can include geophysical, geochemical, geological and engineering instruments to confirm that scientific data requirements at that site will be met. This in situ near real-time data, collected prior to final targeting of the lander, will insure that the sample site is both scientifically valuable and also that it is reachable within limits of the capability of the lander.

Description of the meteoroid detection experiment flown on the Pioneer 10 and 11 Jupiter flyby missions

NASA Technical Reports Server (NTRS)

Oneal, R. L. (Compiler)

1974-01-01

The meteoroid detection experiment has the objective of measuring the population of 10 to the minus 9th power and 10 to the minus 8th power grams mass particles in interplanetary space with emphasis on making these measurements in the Asteroid Belt. The instrument design, which uses the pressurized-cell-penetration detection technique, and the tests involved in obtaining a flight-qualified instrument are described. The successful demonstration of flight-quality penetration detectors to function properly under long-term simulated space environments is also described.

American Association for Pediatric Ophthalmology and Strabismus

MedlinePlus

... to the emergency room or ophthalmologist. If a sharp object has penetrated the eye (like a fish ... room as soon as possible. Other blunt or sharp injuries should be examined by an ophthalmologist, since ...

Work related injuries in small scale commercial fishing

PubMed Central

Marshall, S; Kucera, K; Loomis, D; McDonald, M; Lipscomb, H

2004-01-01

Objective: To describe the epidemiology of work related injury in a group of small scale, independent commercial fishers. Design: Cross sectional survey (baseline instrument of a prospective cohort study). Setting and subjects: Commercial fishers in eastern North Carolina. Results: A cohort of 219 commercial fishers was established and 215 subjects completed an injury questionnaire. The main types of fishing conducted by the cohort were finfishing (159/215) and crabbing (154/215). Of the 215 fishers, 83 reported that they had suffered an injury event in the previous 12 months, a retrospective recall incidence proportion of 38.6 per 100 workers (95% confidence interval 32.1 to 45.1). The 83 injury events resulted in 94 injuries; 47% were penetrating wounds and 24% were strains/sprains. Half of injuries were to the hand/wrist/digits and 13% were to the back. Of the penetrating wounds, 87% were to the hand/wrist/digits, 32% became infected, and 80% were caused by contact with finfish, shellfish, or other marine animal. Of the strains/sprains, 48% were to the back and 26% were to the shoulder. Seventy percent of strains/sprains were caused by moving heavy objects, mainly either while hauling in nets, pots, or lines or loading/unloading the boat. Conclusion: In this group of small scale, independent fishers, the most common reported injuries were penetrating wounds to the hand/wrist/digits from marine animals and strains/sprains to the back while moving heavy objects. PMID:15314048

Transdermal delivery of biomacromolecules using lipid-like nanoparticles

NASA Astrophysics Data System (ADS)

Bello, Evelyn A.

The transdermal delivery of biomacromolecules, including proteins and nucleic acids, is challenging, owing to their large size and the penetration-resistant nature of the stratum corneum. Thus, an urgent need exists for the development of transdermal delivery methodologies. This research focuses on the use of cationic lipid-like nanoparticles (lipidoids) for the transdermal delivery of proteins, and establishes an in vitro model for the study. The lipidoids used were first combinatorially designed and synthesized; afterwards, they were employed for protein encapsulation in a vesicular system. A skin penetration study demonstrated that lipidoids enhance penetration depth in a pig skin model, overcoming the barrier that the stratum corneum presents. This research has successfully identified active lipidoids capable of efficiently penetrating the skin; therefore, loading proteins into lipidoid nanoparticles will facilitate the transdermal delivery of proteins. Membrane diffusion experiments were used to confirm the results. This research has confirmed that lipidoids are a suitable material for transdermal protein delivery enhancement.

Colon Trauma: Evidence-Based Practices.

PubMed

Yamamoto, Ryo; Logue, Alicia J; Muir, Mark T

2018-01-01

Colon injury is not uncommon and occurs in about a half of patients with penetrating hollow viscus injuries. Despite major advances in the operative management of penetrating colon wounds, there remains discussion regarding the appropriate treatment of destructive colon injuries, with a significant amount of scientific evidence supporting segmental resection with primary anastomosis in most patients without comorbidities or large transfusion requirement. Although literature is sparse concerning the management of blunt colon injuries, some studies have shown operative decision based on an algorithm originally defined for penetrating wounds should be considered in blunt colon injuries. The optimal management of colonic injuries in patients requiring damage control surgery (DCS) also remains controversial. Studies have recently reported that there is no increased risk compared with patients treated without DCS if fascial closure is completed on the first reoperation, or that a management algorithm for penetrating colon wounds is probably efficacious for colon injuries in the setting of DCS as well.

Penetration of sunlight into a canopy - Explicit models based on vertical and horizontal leaf projections

NASA Technical Reports Server (NTRS)

Otterman, J.; Brakke, T.

1986-01-01

The projections of leaf areas onto a horizontal plane and onto a vertical plane are examined for their utility in characterizing canopies for sunlight penetration (direct beam only) models. These projections exactly specify the penetration if the projections on the principal plane of the normals to the top surfaces of the leaves are in the same quadrant as the sun. Inferring the total leaf area from these projections (and therefore the penetration as a function of the total leaf area) is possible only with a large uncertainty (up to + or - 32 percent) because the projections are a specific measure of the total leaf area only if the leaf angle distribution is known. It is expected that this uncertainty could be reduced to more acceptable levels by making an approximate assessment of whether the zenith angle distribution is that of an extremophile canopy.

Analysis and measurements of low frequency lightning component penetration through aerospace vehicle metal and graphite skins

NASA Technical Reports Server (NTRS)

Robb, J. D.; Chen, T.

1980-01-01

An analysis of the shielding properties of mixed metal and graphite composite structures has illustrated some important aspects of electromagnetic field penetration into the interior. These include: (1) that graphite access doors on metallic structures will attenuate lightning magnetic fields very little; conversely, metal doors on a graphite structure will also attenuate fields from lightning strike currents very little, i.e., homogeneity of the shield is a critical factor in shielding and (2) that continuous conductors between two points inside a graphite skin such as an air data probe metallic tubing connection to an air data computer can allow large current penetrations into a vehicle interior. The true weight savings resulting from the use of composite materials can only be evaluated after the resulting electromagnetic problems such as current penetrations have been solved, and this generally requires weight addition in the form of cable shields, conductor bonding or external metallization.

Voluntary Cough Airflow Differentiates Safe versus Unsafe Swallowing in Amyotrophic Lateral Sclerosis

PubMed Central

Plowman, Emily K.; Watts, Stephanie A.; Robison, Raele; Tabor, Lauren; Dion, Charles; Gaziano, Joy; Vu, Tuan; Gooch, Clifton

2016-01-01

Dysphagia and aspiration are prevalent in amyotrophic lateral sclerosis (ALS) and contribute to malnutrition, aspiration pneumonia and death. Early detection of at risk individuals is critical to ensure maintenance of safe oral intake and optimal pulmonary function. We therefore aimed to determine the discriminant ability of voluntary cough airflow measures in detecting penetration/aspiration status in ALS patients. Seventy individuals with ALS (El-Escorial criteria) completed voluntary cough spirometry testing and underwent a standardized videofluoroscopic swallowing evaluation (VFSE). A rater blinded to aspiration status derived six objective measures of voluntary cough airflow and evaluated airway safety using the Penetration Aspiration Scale (PAS). A between groups ANOVA (safe vs. unsafe swallowers) was conducted and sensitivity, specificity, area under the curve (AUC) and likelihood ratios were calculated. VFSE analysis revealed 24 penetrator/aspirators (PAS ≥3) and 46 non-penetrator/aspirators (PAS ≤2). Cough volume acceleration (CVA), peak expiratory flow rise time (PEFRT), and peak expiratory flow rate (PEFR) were significantly different between airway safety groups (p <0.05) and demonstrated significant discriminant ability to detect the presence of penetration/aspiration with AUC values of: 0.85, 0.81, and 0.78 respectively. CVA < 45.28L/s/s, PEFR <3.97L/s, and PEFRT > 76ms had sensitivities of 91.3%, 82.6% and 73.9% respectively and specificities of 82.2%, 73.9%, and 78.3% for identifying ALS penetrator/aspirators. Voluntary cough airflow measures identified ALS patients at risk for penetration/aspiration and may be a valuable screening tool with high clinical utility. PMID:26803772

Penetration experiments in aluminum 1100 targets using soda-lime glass projectiles

NASA Technical Reports Server (NTRS)

Horz, Friedrich; Cintala, Mark J.; Bernhard, Ronald P.; Cardenas, Frank; Davidson, William E.; Haynes, Gerald; See, Thomas H.; Winkler, Jerry L.

1995-01-01

The cratering and penetration behavior of annealed aluminum 1100 targets, with thickness varied from several centimeters to ultra-thin foils less than 1 micrometer thick, were experimentally investigated using 3.2 mm diameter spherical soda-lime glass projectiles at velocities from 1 to 7 km/s. The objective was to establish quantitative, dimensional relationships between initial impact conditions (impact velocity, projectile diameter, and target thickness) and the diameter of the resulting crater or penetration hole. Such dimensional relationships and calibration experiments are needed to extract the diameters and fluxes of hypervelocity particles from space-exposed surfaces and to predict the performance of certain collisional shields. The cratering behavior of aluminum 1100 is fairly well predicted. However, crater depth is modestly deeper for our silicate impactors than the canonical value based on aluminum projectiles and aluminum 6061-T6 targets. The ballistic-limit thickness was also different. These differences attest to the great sensitivity of detailed crater geometry and penetration behavior on the physical properties of both the target and impactor. Each penetration experiment was equipped with a witness plate to monitor the nature of the debris plume emanating from the rear of the target. This plume consists of both projectile fragments and target debris. Both penetration hole and witness-plate spray patterns systematically evolve in response to projectile diameter/target thickness. The relative dimensions of the projectile and target totally dominate the experimental products documented in this report; impact velocity is an important contributor as well to the evolution of penetration holes, but is of subordinate significance for the witness-plate spray patterns.

Tracking ocean heat uptake during the surface warming hiatus

DOE PAGES

Liu, Wei; Xie, Shang -Ping; Lu, Jian

2016-03-30

Ocean heat uptake is observed to penetrate deep during the recent hiatus1,2,3 of global warming in the Atlantic and Southern Ocean. This has been suggested to indicate that the two regions are the driver of the surface warming hiatus4. We show that the deep heat penetration in the Atlantic and Southern Ocean is not unique to the hiatus but common to the past four decades including the 1970s-90s epoch of accelerated surface warming. Our analyses of a large ensemble simulation5 confirm the deep heat penetration in the Atlantic and Southern Ocean in ensemble members with or without surface warming hiatusmore » in the early 21th century. During the past four decades, the global ocean heat content (OHC) of upper 1500m is dominated by a warming trend, and the depth of anthropogenic heat penetration merely reflects the depth of the mean meridional overturning circulation in the basin. Furthermore, the heat penetration depth is not a valid basis to infer the hiatus mechanism.« less

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Veda, Santosh

2017-04-11

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interestmore » to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.« less

Tracking ocean heat uptake during the surface warming hiatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Wei; Xie, Shang -Ping; Lu, Jian

Ocean heat uptake is observed to penetrate deep during the recent hiatus1,2,3 of global warming in the Atlantic and Southern Ocean. This has been suggested to indicate that the two regions are the driver of the surface warming hiatus4. We show that the deep heat penetration in the Atlantic and Southern Ocean is not unique to the hiatus but common to the past four decades including the 1970s-90s epoch of accelerated surface warming. Our analyses of a large ensemble simulation5 confirm the deep heat penetration in the Atlantic and Southern Ocean in ensemble members with or without surface warming hiatusmore » in the early 21th century. During the past four decades, the global ocean heat content (OHC) of upper 1500m is dominated by a warming trend, and the depth of anthropogenic heat penetration merely reflects the depth of the mean meridional overturning circulation in the basin. Furthermore, the heat penetration depth is not a valid basis to infer the hiatus mechanism.« less

Dual-drug nanomedicine with hydrophilic F127-modified magnetic nanocarriers assembled in amphiphilic gelatin for enhanced penetration and drug delivery in deep tumor tissue.

PubMed

Lai, Yen-Ho; Chiang, Chih-Sheng; Kao, Tzu-Hsun; Chen, San-Yuan

2018-01-01

Deep penetration of large-sized drug nanocarriers into tumors is important to improve the efficacy of tumor therapy. In this study, we developed a size-changeable "Trojan Horse" nanocarrier (THNC) composed of paclitaxel (PTX)-loaded Greek soldiers (GSs; ~20 nm) assembled in an amphiphilic gelatin matrix with hydrophilic losartan (LST) added. With amphiphilic gelatin matrix cleavage by matrix metalloproteinase-2, LST showed fast release of up to 60% accumulated drug at 6 h, but a slow release kinetic (~20%) was detected in the PTX from the GSs, indicating that THNCs enable controllable release of LST and PTX drugs for penetration into the tumor tissue. The in vitro cell viability in a 3D tumor spheroid model indicated that the PTX-loaded GSs liberated from THNCs showed deeper penetration as well as higher cytotoxicity, reducing a tumor spheroid to half its original size and collapsing the structure of the tumor microenvironment. The results demonstrate that the THNCs with controlled drug release and deep penetration of magnetic GSs show great potential for cancer therapy.

Newton on Objects Moving in a Fluid--The Penetration Length

ERIC Educational Resources Information Center

Saslow, Wayne M.; Lu, Hong

2008-01-01

We solve for the motion of an object with initial velocity v[subscript 0] and subject only to the combined drag of forces linear and quadratic in the velocity. This problem was treated briefly by Newton, after he developed a theoretical argument for the quadratic term, which we now know is characteristic of turbulent flow. Linear drag introduces a…

PNNL Expert Doug McMakin Discusses Millimeter Wave Technology

ScienceCinema

McMakin, Doug

2018-02-13

Electrical Engineer Doug McMakin discusses Millimeter Wave Holographic technology, which uses non-harmful, ultrahigh-frequency radio waves to penetrate clothing to detect and identify concealed objects, as well as obtain accurate body measurements.

Mechanism of nanosecond laser drilling process of 4H-SiC for through substrate vias

NASA Astrophysics Data System (ADS)

Kim, Byunggi; Iida, Ryoichi; Doan, Duc Hong; Fushinobu, Kazuyoshi

2017-06-01

Role of optical parameters on nanosecond laser drilling of 4H-SiC was experimentally studied. Using ns pulsed Nd:YAG laser, parametric studies on effects of wavelength (1064 nm or 532 nm), beam profile (Gaussian or Bessel), and ambient condition (air or water) were conducted. The wavelengths which have large optical penetration depth were selected as wavefront has to propagate through materials to generate Bessel beam. The experimental results showed that carbonization of SiC surface accelerates thermal ablation of the materials with fluence under the lattice melting threshold. Especially, pattern of side lobes with small fluence was formed by irradiation of Bessel beam. The pattern disturbed penetration of wavefronts through materials. Implementation of water environment was not effective to suppress carbonization and had slight effect on improvement of drilling quality. For this reason, deep drilling with small entrance was not achieved using Bessel beam. Irradiation of 1064 nm Gaussian beam with large fluence led to formation of critical amount of re-solidified silicon due to the large optical penetration depth. Carbonization and silicon formation had a significant effect on unique fluence dependence of drilling depth. Absorption mechanism was studied as well to discuss effect of wavelength on processing characteristics.

Penetrators for delivering Scientific equipment to minor bodies by flying-pass missions.

NASA Astrophysics Data System (ADS)

Bagrov, Alexander; Martynov, Maxim; Pichkhadze, Konstantin M.; Dolgopolov, Vladimir; Sysoev, Valentin

Many space missions are planned to have close encounters with Solar system minor bodies as a pass-fly. Short time of such close encounters were effectively used for photographing of these bodies, i.e. for distant investigations only because of large velocities of the encounter. We propose to use high-velocity penetrators to provide contact investigations of the minor bodies in situ. These devices were designed by Lavochkin Association for lunar missions. They were designed for long lived scientific equipment to be placed under surface up to depth 2...3 m. Penetrators could survive under 500 g shock, so the contact velocity was from 90 to 250 m/s, so each of them had booster engine to decelerate orbital velocity. As flying-pass velocity near minor body can be more then 10 km/s, penetrators would hit target at speed above 1 km/s and successfully bear 1500 g. To do so we propose to fulfill whole internal space inside penetrator with distilled water and froze it to temperature - 80°C or lower. At this temperature water ice is as hard as steel, so penetrator will plunge into target like armour-piercing shell. After landing protective ice will be evaporated (particularly due to heating from collision) and all sensitive mechanics will be set free.

Feedbacks between soil penetration resistance, root architecture and water uptake limit water accessibility and crop growth - A vicious circle.

PubMed

Colombi, Tino; Torres, Lorena Chagas; Walter, Achim; Keller, Thomas

2018-06-01

Water is the most limiting resource for global crop production. The projected increase of dry spells due to climate change will further increase the problem of water limited crop yields. Besides low water abundance and availability, water limitations also occur due to restricted water accessibility. Soil penetration resistance, which is largely influenced by soil moisture, is the major soil property regulating root elongation and water accessibility. Until now the interactions between soil penetration resistance, root system properties, water uptake and crop productivity are rarely investigated. In the current study we quantified how interactive effects between soil penetration resistance, root architecture and water uptake affect water accessibility and crop productivity in the field. Maize was grown on compacted and uncompacted soil that was either tilled or remained untilled after compaction, which resulted in four treatments with different topsoil penetration resistance. Higher topsoil penetration resistance caused root systems to be shallower. This resulted in increased water uptake from the topsoil and hence topsoil drying, which further increased the penetration resistance in the uppermost soil layer. As a consequence of this feedback, root growth into deeper soil layers, where water would have been available, was reduced and plant growth decreased. Our results demonstrate that soil penetration resistance, root architecture and water uptake are closely interrelated and thereby determine the potential of plants to access soil water pools. Hence, these interactions and their feedbacks on water accessibility and crop productivity have to be accounted for when developing strategies to alleviate water limitations in cropping systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Injuries to law enforcement officers: the backface signature injury.

PubMed

Wilhelm, Marianne; Bir, Cynthia

2008-01-15

In today's law enforcement community, one of the most vital tools an officer can possess is personal body armor. However, a recent Department of Justice investigation has raised important questions regarding the protection actually afforded officers through the use of personal body armor, and the current test methods used to assess the armor. Test results show that most Zylon-containing vests showed deformations in excess of the 0101.04 Standard's 44 mm backface signature limit. Such increased deformation can lead to serious injuries, including backface signature injuries, which have occurred in the field. Although the vest is successful in containing the round, it is not effectively dissipating the energy enough to prevent large amounts of vest deformation at the area of impact. Therefore, open, penetrating wounds occur even though the bullet did not penetrate the vest. The objective of the current study was to further define the backface signature injury through the use of case studies and laboratory experiments. Following the case study investigation, backface signature testing was conducted using a clay medium based on the NIJ 0101.04 Standard. The final component of this research involved the use of post-mortem human specimens (PMHS) for further investigation of the backface signature injury. Although the underlying cause of backface signature injuries is unknown, energy density is likely to play a role in the mechanism. Energy density (E/a) is defined as the energy per unit area and has been previously used in less lethal skin penetration research. Further research into the underlying causes of backface signature injuries is necessary. In addition to armor testing, the study of law enforcement personnel who have been shot while wearing soft body armor is also a valuable tool for determining the effectiveness of certification standards. Finally, it is important for medical personnel to recognize the backface signature injury and document this as a type of injury separate from blunt trauma or penetrating trauma behind armor injuries. Detailed knowledge of the injury, including the depth of the wound, would be beneficial to the scientific community.

Regional difference of the vertical structure of seasonal thermocline and its impact on sea surface temperature in the North Pacific

NASA Astrophysics Data System (ADS)

Yamaguchi, R.; Suga, T.

2016-12-01

Recent observational studies show that, during the warming season, a large amount of heat flux is penetrated through the base of thin mixed layer by vertical eddy diffusion, in addition to penetration of solar radiation [1]. In order to understand this heat penetration process due to vertical eddy diffusivity and its contribution to seasonal variation of sea surface temperature, we investigated the evolution of thermal stratification below the summertime thin mixed layer (i.e. evolution of seasonal thermocline) and its vertical structure in the North Pacific using high vertical resolution temperature profile observed by Argo floats. We quantified the vertical structure of seasonal thermocline as deviations from the linear structure where the vertical gradient of temperature is constant, that is, "shape anomaly". The shape anomaly is variable representing the extent of the bend of temperature profiles. We found that there are larger values of shape anomaly in the region where the seasonal sea surface temperature warming is relatively faster. To understand the regional difference of shape anomalies, we investigated the relationship between time changes in shape anomalies and net surface heat flux and surface kinetic energy flux. From May to July, the analysis indicated that, in a large part of North Pacific, there's a tendency for shape anomalies to develop strongly (weakly) under the conditions of large (small) downward net surface heat flux and small (large) downward surface kinetic energy flux. Since weak (strong) development of shape anomalies means efficient (inefficient) downward heat transport from the surface, these results suggest that the regional difference of the downward heat penetration below mixed layer is explained reasonably well by differences in surface heat forcing and surface wind forcing in a vertical one dimensional framework. [1] Hosoda et al. (2015), J. Oceanogr., 71, 541-556.

High resolution imaging of objects located within a wall

NASA Astrophysics Data System (ADS)

Greneker, Eugene F.; Showman, Gregory A.; Trostel, John M.; Sylvester, Vincent

2006-05-01

Researchers at Georgia Tech Research Institute have developed a high resolution imaging radar technique that allows large sections of a test wall to be scanned in X and Y dimensions. The resulting images that can be obtained provide information on what is inside the wall, if anything. The scanning homodyne radar operates at a frequency of 24.1 GHz at with an output power level of approximately 10 milliwatts. An imaging technique that has been developed is currently being used to study the detection of toxic mold on the back surface of wallboard using radar as a sensor. The moisture that is associated with the mold can easily be detected. In addition to mold, the technique will image objects as small as a 4 millimeter sphere on the front or rear of the wallboard and will penetrate both sides of a wall made of studs and wallboard. Signal processing is performed on the resulting data to further sharpen the image. Photos of the scanner and images produced by the scanner are presented. A discussion of the signal processing and technical challenges are also discussed.

Skin penetration and photoprotection of topical formulations containing benzophenone-3 solid lipid microparticles prepared by the solvent-free spray-congealing technique.

PubMed

Martins, Rodrigo Molina; Siqueira, Silvia; Fonseca, Maria José Vieira; Freitas, Luis Alexandre Pedro

2014-01-01

Solid-lipid microparticles loaded with high amounts of the sunscreen UV filter benzophenone-3 were prepared by spray congealing with the objective of decreasing its skin penetration and evaluate whether the sunscreen's photoprotection were impaired by the microencapsulation process. The microparticles were produced using the natural lipids carnauba wax or bees wax and three different concentrations of benzophenone-3 (30, 50 and 70%) using spray congealing technique. The microparticles presented properties suitable for topical application, such as spherical morphology, high encapsulation efficiency (95.53-102.2%), average particle sizes between 28.5 and 60.0 µm with polydispersivities from 1.2 to 2.5. In studies of in vitro skin penetration and preliminary stability, formulations of gel cream containing carnauba wax solid lipid microparticles and 70% benzophenone-3 when compared to the formulation added of bees wax solid-lipid microparticles containing 70% benzophenone-3, was stable considering the several parameters evaluated and were able to decrease the penetration of the UV filter into pig skin. Moreover, the formulations containing solid lipid microparticles with 70% benzophenone-3 increased the photoprotective capacity of benzophenone-3 under UV irradiation. The results show that spray-congealed microparticles are interesting solid forms to decrease the penetration solar filters in the skin without compromising their photoprotection.

Cost Implications of Organizing Nursing Home Workforce in Teams

PubMed Central

Mukamel, Dana B; Cai, Shubing; Temkin-Greener, Helena

2009-01-01

Objective To estimate the costs associated with formal and self-managed daily practice teams in nursing homes. Data Sources/Study Setting Medicaid cost reports for 135 nursing homes in New York State in 2006 and survey data for 6,137 direct care workers. Study Design A retrospective statistical analysis: We estimated hybrid cost functions that include team penetration variables. Inference was based on robust standard errors. Data Collection Formal and self-managed team penetration (i.e., percent of staff working in a team) were calculated from survey responses. Annual variable costs, beds, case mix-adjusted days, admissions, home care visits, outpatient clinic visits, day care days, wages, and ownership were calculated from the cost reports. Principal Findings Formal team penetration was significantly associated with costs, while self-managed teams penetration was not. Costs declined with increasing penetration up to 13 percent of formal teams, and increased above this level. Formal teams in nursing homes in the upward sloping range of the curve were more diverse, with a larger number of participating disciplines and more likely to include physicians. Conclusions Organization of workforce in formal teams may offer nursing homes a cost-saving strategy. More research is required to understand the relationship between team composition and costs. PMID:19486181

How soft is that pillow? The perceptual localization of the hand and the haptic assessment of contact rigidity

PubMed Central

Pressman, Assaf; Karniel, Amir; Mussa-Ivaldi, Ferdinando A.

2011-01-01

A new haptic illusion is described, in which the location of the mobile object affects the perception of its rigidity. There is theoretical and experimental support to the notion that limb position sense results from the brain combining ongoing sensory information with expectations arising from prior experience. How does this probabilistic state information affect one’s tactile perception of the environment mechanics? In a simple estimation process human subjects were asked to report the relative rigidity of two simulated virtual objects. One of the objects remained fixed in space and had various coefficients of stiffness. The other virtual object had constant stiffness but moved with respect to the subjects. Earlier work suggested that the perception of an object’s rigidity is consistent with a process of regression between the contact force and the perceived amount of penetration inside the object’s boundary. The amount of penetration perceived by the subject was affected by varying the position of the object. This, in turn, had a predictable effect on the perceived rigidity of the contact. Subjects’ reports on the relative rigidity of the object are best accounted for by a probabilistic model in which the perceived boundary of the object is estimated based on its current location and on its past observations. Therefore, the perception of contact rigidity is accounted for by a stochastic process of state estimation underlying proprioceptive localization of the hand. PMID:21525300

Deep Space 2: The Mars Microprobe Mission

NASA Astrophysics Data System (ADS)

Smrekar, Suzanne; Catling, David; Lorenz, Ralph; Magalhães, Julio; Moersch, Jeffrey; Morgan, Paul; Murray, Bruce; Presley-Holloway, Marsha; Yen, Albert; Zent, Aaron; Blaney, Diana

The Mars Microprobe Mission will be the second of the New Millennium Program's technology development missions to planetary bodies. The mission consists of two penetrators that weigh 2.4 kg each and are being carried as a piggyback payload on the Mars Polar Lander cruise ring. The spacecraft arrive at Mars on December 3, 1999. The two identical penetrators will impact the surface at ~190 m/s and penetrate up to 0.6 m. They will land within 1 to 10 km of each other and ~50 km from the Polar Lander on the south polar layered terrain. The primary objective of the mission is to demonstrate technologies that will enable future science missions and, in particular, network science missions. A secondary goal is to acquire science data. A subsurface evolved water experiment and a thermal conductivity experiment will estimate the water content and thermal properties of the regolith. The atmospheric density, pressure, and temperature will be derived using descent deceleration data. Impact accelerometer data will be used to determine the depth of penetration, the hardness of the regolith, and the presence or absence of 10 cm scale layers.

Preliminary Estimate for Injury Criterion to Immediate Incapacitation by Projectile Penetration

DTIC Science & Technology

2012-01-01

tissues with different mechanical properties. The questions then arise: How representative of the real target is ballistic gelatine and how does the...of penetration of a typical fragment at varying velocity was computed. The characteristics of different tissues composing the human torso and their...based on the observation that to hit critical organs (the CNS as well as the heart and large arteries), 30 to 45 cm of tissues (human or animal) has

Subsurface valleys and geoarcheology of the Eastern Sahara revealed by shuttle radar

USGS Publications Warehouse

McCauley, J.F.; Schaber, G.G.; Breed, C.S.; Grolier, M.J.; Haynes, C.V.; Issawi, B.; Elachi, C.; Blom, R.

1982-01-01

The shuttle imaging radar (SIR-A) carried on the space shuttle Columbia in November 1981 penetrated the extremely dry Selima Sand Sheet, dunes, and drift sand of the eastern Sahara, revealing previously unknown buried valleys, geologic structures, and possible Stone Age occupation sites. Radar responses from bedrock and gravel surfaces beneath windblown sand several centimeters to possibly meters thick delineate sand- and alluvium-filled valleys, some nearly as wide as the Nile Valley and perhaps as old as middle Tertiary. The nov-vanished maijor river systems that carved these large valleys probably accomplished most of the erosional stripping of this extraordinarily flat, hyperarid region. Underfit and incised dry wadis, many superimposed on the large valleys, represent erosion by intermittent running water, probably during Quaternary pluvials. Stone Age artifacts associated with soils in the alluvium suggest that areas near the wadis may have been sites of early human occupation. The presence of old drainage networks beneath the sand sheet provides a geologic explanation for the locations of many playas and present-day oases which have been centers of episodic human habitation. Radar penetration of dry sand and soils varies with the wavelength of the incident signals (24 centimeters for the SIR-A system), incidence angle, and the electrical properties of the materials, which are largely determined by moisture content. The calculated depth of radar penetration of dry sand and granules, based on laboratory measurements of the electrical properties of samples from the Selima Sand Sheet, is at least 5 meters. Recent (September 1982) field studies in Egypt verified SIR-A signal penetration depths of at least 1 meter in the Selima Sand Sheet and in drift sand and 2 or more meters in sand dunes. Copyright ?? 1982 AAAS.

Calcified lesion modeling for excimer laser ablation

NASA Astrophysics Data System (ADS)

Scott, Holly A.; Archuleta, Andrew; Splinter, Robert

2009-06-01

Objective: Develop a representative calcium target model to evaluate penetration of calcified plaque lesions during atherectomy procedures using 308 nm Excimer laser ablation. Materials and Methods: An in-vitro model representing human calcified plaque was analyzed using Plaster-of-Paris and cement based composite materials as well as a fibrinogen model. The materials were tested for mechanical consistency. The most likely candidate(s) resulting from initial mechanical and chemical screening was submitted for ablation testing. The penetration rate of specific multi-fiber catheter designs and a single fiber probe was obtained and compared to that in human cadaver calcified plaque. The effects of lasing parameters and catheter tip design on penetration speed in a representative calcified model were verified against the results in human cadaver specimens. Results: In Plaster of Paris, the best penetration was obtained using the single fiber tip configuration operating at 100 Fluence, 120 Hz. Calcified human lesions are twice as hard, twice as elastic as and much more complex than Plaster of Paris. Penetration of human calcified specimens was highly inconsistent and varied significantly from specimen to specimen and within individual specimens. Conclusions: Although Plaster of Paris demonstrated predictable increases in penetration with higher energy density and repetition rate, it can not be considered a totally representative laser ablation model for calcified lesions. This is in part due to the more heterogeneous nature and higher density composition of cadaver intravascular human calcified occlusions. Further testing will require a more representative model of human calcified lesions.

Treatment of Penetrating Nonmissile Traumatic Brain Injury. Case Series and Review of the Literature.

PubMed

Zyck, Stephanie; Toshkezi, Gentian; Krishnamurthy, Satish; Carter, David A; Siddiqui, Adnan; Hazama, Ali; Jayarao, Mayur; Chin, Lawrence

2016-07-01

Penetrating traumatic brain injuries (TBIs), with the exception of gunshot wounds, are relatively rare occurrences and affect all ages. Clinical presentation varies depending on the mechanism of the injury. Prompt surgical treatment is often indicated and is influenced by patient clinical examination, anatomic trajectory, and the penetrating object's size, shape, and velocity. We present 3 cases of penetrating TBI. Their similarities and differences affecting operative and medical management are compared. We relate our experience with management of penetrating intracranial foreign bodies in general and discuss the relevant literature. Our first case was a 12-year-old male who presented with a self-inflicted transfacial transcranial injury by a crossbow. The arrow passed through the left sphenoid and cavernous sinus and exited through the parietal calvarium. Our second case was a 37-year-old man with a transoral intracranial stab wound by a knife. In our third case, we present a 46-year-old male who accidentally fired a nail gun into his right ear. The nail traversed the posterior wall of the external auditory canal into the posterior fossa, ending in the cerebellar vermis. Each case was treated with craniotomy and foreign body removal. All resulted in good outcomes after surgical treatment. Surgery in penetrating TBI is the treatment of choice. Our cases demonstrate how certain principles applied to individual patient scenarios may optimize clinical results. Severity of the injury and operative approach are among the most important considerations to achieve the best patient outcomes. Published by Elsevier Inc.

Explosive hazard detection using MIMO forward-looking ground penetrating radar

NASA Astrophysics Data System (ADS)

Shaw, Darren; Ho, K. C.; Stone, Kevin; Keller, James M.; Popescu, Mihail; Anderson, Derek T.; Luke, Robert H.; Burns, Brian

2015-05-01

This paper proposes a machine learning algorithm for subsurface object detection on multiple-input-multiple-output (MIMO) forward-looking ground-penetrating radar (FLGPR). By detecting hazards using FLGPR, standoff distances of up to tens of meters can be acquired, but this is at the degradation of performance due to high false alarm rates. The proposed system utilizes an anomaly detection prescreener to identify potential object locations. Alarm locations have multiple one-dimensional (ML) spectral features, two-dimensional (2D) spectral features, and log-Gabor statistic features extracted. The ability of these features to reduce the number of false alarms and increase the probability of detection is evaluated for both co-polarizations present in the Akela MIMO array. Classification is performed by a Support Vector Machine (SVM) with lane-based cross-validation for training and testing. Class imbalance and optimized SVM kernel parameters are considered during classifier training.

A case of nodal malignant lymphoma presenting with arterial bleeding related to its duodenal penetration.

PubMed

Miyake, Takakazu; Iida, Tomoya; Masaki, Yoshiharu; Onodera, Kei; Kubo, Toshiyuki; Yamashita, Kentaro; Yamano, Hiroo; Nakase, Hiroshi

2018-06-01

A 62-year-old man with a chief complaint of dysphagia visited our hospital. Enhanced computed tomography showed the tumor near the duodenal wall and lymphadenopathy in the left supraclavicular fossa and para-aortic lymph node. Upper gastrointestinal endoscopy showed an ulcer accompanied with a fistula in the anterior wall of duodenal bulb, suggesting that the tumor penetrated into duodenal wall. Biopsy from the lymph node in the left supraclavicular fossa indicated diffuse large B-cell lymphoma. Although chemotherapy was planned, massive arterial bleeding occurred from the part of duodenal penetration. Endoscopic hemostasis was unsuccessfully performed. Therefore, we performed transcathether arterial embolization for hemostasis. After the procedure, the patient received six cycles of chemotherapy, and he achieved complete response. He has been alive 5 years without recurrence. There were many cases of gastrointestinal bleeding from primary gastrointestinal lymphomas, while there were few cases with nodal involvement by malignant lymphoma resulting in bleeding from gastrointestinal tract. We herein report a case of duodenal bleeding by nodal involvement of diffuse large B-cell lymphoma with review of literature.

Vertical drag force acting on intruders of different shapes in granular media

NASA Astrophysics Data System (ADS)

Zaidi, Ali Abbas; Müller, Christoph

2017-06-01

The penetration of large objects into granular media is encountered commonly both in nature (e.g. impacts of meteors and projectiles) and engineering applications (e.g. insertion of tractor blades into sand). The motion of the impacting intruder in granular media is resisted by a granular drag force. In this work, we assess the effect of intruder shape on the granular drag force using discrete element modelling (DEM). The following intruder shapes were modelled: spherical, conical, cylindrical and cubical. We observed that the drag force can be described well by a power-law relationship with intrusion depth, independent of the intruder shape. However, the exponent of the power-law expression increases with increasing "flatness" of the intruder's impacting surface due to an increasing fraction of the granular media affected by the impact of the intruder.

Porcelain-coated antenna for radio-frequency driven plasma source

DOEpatents

Leung, K.N.; Wells, R.P.; Craven, G.E.

1996-12-24

A new porcelain-enamel coated antenna creates a clean plasma for volume or surface-conversion ion sources. The porcelain-enamel coating is hard, electrically insulating, long lasting, non fragile, and resistant to puncture by high energy ions in the plasma. Plasma and ion production using the porcelain enamel coated antenna is uncontaminated with filament or extraneous metal ions because the porcelain does not evaporate and is not sputtered into the plasma during operation. Ion beams produced using the new porcelain-enamel coated antenna are useful in ion implantation, high energy accelerators, negative, positive, or neutral beam applications, fusion, and treatment of chemical or radioactive waste for disposal. For ion implantation, the appropriate species ion beam generated with the inventive antenna will penetrate large or small, irregularly shaped conducting objects with a narrow implantation profile. 8 figs.

Non Destructive Test Dye Penetrant and Ultrasonic on Welding SMAW Butt Joint with Acceptance Criteria ASME Standard

NASA Astrophysics Data System (ADS)

Endramawan, T.; Sifa, A.

2018-02-01

The purpose of this research is to know the type of discontinuity of SMAW welding result and to determine acceptance criteria based on American Society of Mechanical Engineer (ASME) standard. Material used is mild steel 98,71% Fe and 0,212% C with hardness 230 VHN with specimen diameter 20 cm and thickness 1.2 cm which is welded use SMAW butt joint with electrode for rooting LB 52U diameter 2.6 mm, current 70 Ampere and voltage 380 volt, filler used LB 5218 electrode diameter 3.2 mm with current 80 Ampere and 380 volt. The method used to analyze the welded with non destructive test dye penetrant (PT) method to see indication on the surface of the object and Ultrasonic (UT) to see indication on the sub and inner the surface of the object, the result is discontinuity recorded and analyzed and then the discontinuity is determine acceptance criteria based on the American Society of Mechanical Engineer (ASME) standards. The result show the discontinuity of porosity on the surface of the welded and inclusion on sub material used ultrasonic test, all indication on dye penetrant or ultrasonic test if there were rejected of result of welded that there must be gouging on part which rejected and then re-welding.

The Auto-Gopher: A Wireline Rotary-Percussive Deep Sampler

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Zacny, Kris; Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Paulsen, Gale L.; Beegle, Luther

2016-01-01

Accessing regions on planetary bodies that potentially preserved biosignatures or are presently habitable is vital to meeting NASA solar system "Search for Life" exploration objectives. To address these objectives, a wireline deep rotary-percussive corer called Auto-Gopher was developed. The percussive action provides effective material fracturing and the rotation provides effective cuttings removal. To increase the drill's penetration rate, the percussive and rotary motions are operated simultaneously. Initially, the corer was designed as a percussive mechanism for sampling ice and was demonstrated in 2005 in Antarctica reaching about 2 m deep. The lessons learned suggested the need to use a combination of rotation and hammering to maximize the penetration rate. This lesson was implemented into the Auto-Gopher-I deep drill which was demonstrated to reach 3-meter deep in gypsum. The average drilling power that was used has been in the range of 100-150 Watt, while the penetration rate was approximately 2.4 m/hr. Recently, a task has started with the goal to develop Auto-Gopher-II that is equipped to execute all the necessary functions in a single drilling unit. These functions also include core breaking, retention and ejection in addition drilling. In this manuscript, the Auto-Gopher-II, its predecessors and their capability are described and discussed.

MO-FG-CAMPUS-IeP2-05: Feasibility Demonstration of High-Voltage Clinical CT and Impact On X-Ray Penetration Through Metal Objects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Y; De Man, B; Robinson, V

Purpose: To demonstrate the possibility and quantify the impact of operating a clinical CT scanner at exceptionally high x-ray tube voltage for better penetration through metal objects and facilitating metal artifact reduction. Methods: We categorize metal objects according to the data corruption severeness (level of distortion and complete photon starvation fraction). To demonstrate feasibility and investigate the impact of high voltage scanning we modified a commercial GE LightSpeed VCT scanner (generator and software) to enable CT scans with x-ray tube voltages as high as 175 kVp. A 20 cm diameter water phantom with two metal rods (10 mm stainless andmore » 25 mm titanium) and a water phantom with realistic metal object (spine cage) were used to evaluate the data corruption and image artifacts in the absence of any algorithm correction. We also performed simulations to confirm our understanding of the transmitted photon levels through metal objects with different size and composition. Results: The reconstructed images at 175 kVp still have significant dark shading artifacts, as expected since no special scatter correction or beam hardening was performed but show substantially lower noise and photon starvation than at lower kVp due to better beam penetration. Analysis of the raw data shows that the photon starved data is reduced from over 4% at 140 kVp to below 0.2% at 175 kVp. The simulations indicate that for clinically relevant titanium and stainless objects a 175 kVp tube voltage effectively avoids photon starvation. Conclusion: The use of exceptionally high tube voltage on a clinical CT system is a practical and effective solution to avoid photon starvation caused by certain metal implants. Sparse and hybrid high-voltage protocols are being considered to maintain low patient dose. This opens the door to algorithmic physics-based corrections rather than treating the data as missing and relying on missing data algorithms. Some of the authors are employees of General Electric.« less

Comet deflection by directed energy: a finite element analysis

NASA Astrophysics Data System (ADS)

Madajian, Jonathan; Griswold, Janelle; Gandra, Anush; Hughes, Gary B.; Zhang, Qicheng; Rupert, Nic; Lubin, Philip

2016-09-01

Comets and Asteroids are viable threats to our planet; if these space rocks are smaller than 25 meters, they burn up in the atmosphere, but if they are wider than 25 meters they can cause damage to the impact area. Anything more than one to two kilometers can have worldwide effects, furthermore a mile-wide asteroid travelling at 30,000 miles per hour has the energy equal to a megaton bomb and is very likely to wipe out most of the life on Earth. Residents near Chelyabinsk, Russia experienced the detrimental effects of a collision with a Near-Earth Asteroid (NEA) on 15 February 2013 as a 20 m object penetrated the atmosphere above that city. The effective yield from this object was approximately 1/2 Megaton TNT equivalent (Mt), or that of a large strategic warhead. The 1908 Tunguska event, also over Russia, is estimated to have had a yield of approximately 15 Mt and had the potential to kill millions of people had it come down over a large city1. In the face of such danger a planetary defense system is necessary and this paper proposes a design for such a system. DE-STAR (Directed Energy System for Targeting of Asteroids and exploRation) is a phased array laser system that can be used to oblate, deflect and de-spin asteroids and comets.

Changes in the Economic Value of Variable Generation at High Penetration Levels: A Pilot Case Study of California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, Andrew; Wiser, Ryan

2012-05-18

We estimate the long-run economic value of variable renewable generation with increasing penetration using a unique investment and dispatch model that captures long-run investment decisions while also incorporating detailed operational constraints and hourly time resolution over a full year. High time resolution and the incorporation of operational constraints are important for estimating the economic value of variable generation, as is the use of a modeling framework that accommodates new investment decisions. The model is herein applied with a case study that is loosely based on California in 2030. Increasing amounts of wind, photovoltaics (PV), and concentrating solar power (CSP) with and without thermal energy storage (TES) are added one at a time. The marginal economic value of these renewable energy sources is estimated and then decomposed into capacity value, energy value, day-ahead forecast error cost, and ancillary services. The marginal economic value, as defined here, is primarily based on the combination of avoided capital investment cost and avoided variable fuel and operations and maintenance costs from other power plants in the power system. Though the model only captures a subset of the benefits and costs of renewable energy, it nonetheless provides unique insights into how the value of that subset changes with technology and penetration level. Specifically, in this case study implementation of the model, the marginal economic value of all three solar options is found to exceed the value of a flat-block of power (as well as wind energy) by \\more » $$20--30/MWh at low penetration levels, largely due to the high capacity value of solar at low penetration. Because the value of CSP per unit of energy is found to be high with or without thermal energy storage at low penetration, we find little apparent incremental value to thermal storage at low solar penetration in the present case study analysis. The marginal economic value of PV and CSP without thermal storage is found to drop considerably (by more than \\$$70/MWh) as the penetration of solar increases toward 30\\percent on an energy basis. This is due primarily to a steep drop in capacity value followed by a decrease in energy value. In contrast, the value of CSP with thermal storage drops much less dramatically as penetration increases. As a result, at solar penetration levels above 10\\percent, CSP with thermal storage is found to be considerably more valuable relative to PV and CSP without thermal storage. The marginal economic value of wind is found to be largely driven by energy value, and is lower than solar at low penetration. The marginal economic value of wind drops at a relatively slower rate with penetration, however. As a result, at high penetration, the value of wind can exceed the value of PV and CSP without thermal storage. Though some of these findings may be somewhat unique to the specific case study presented here, the results: (1) highlight the importance of an analysis framework that addresses long-term investment decisions as well as short-term dispatch and operational constraints, (2) can help inform long-term decisions about renewable energy procurement and supporting infrastructure, and (3) point to areas where further research is warranted.« less

The impact of the Balanced Budget Act on the utilization and financial condition of children's services in California hospitals.

PubMed

McCue, Michael J

2002-01-01

The objective of this study was to evaluate the utilization and financial performance of children's services after the Balanced Budget Act of 1997. The author analyzed these performance factors by hospital ownership, HMO penetration, and disproportionate share hospitals. Using data from California hospitals and conducting an analysis from 1997 to 1999, the author found that public hospitals were able to increase their profits from pediatric and neonatal intensive care services. The study also revealed that DSH hospitals located in high HMO penetration markets reduced their operating losses in nursery and pediatric services.

Cranial injury caused by penetrating non-missile foreign body: an autopsy case.

PubMed

Eren, B; Türkmen, N; Toprak Ergönen, A; Gündogmus, U N

2012-10-01

Presented case was 32-year-old male marble worker, who underwent industrial accident at workplace. On gross physical examination; on forehead region round skin wound in 0.9 cm diameter was detected, radiological examination showed the image of metallic object. in the skull cavity. Brain dissection showed obvious brain injury, haemorrahge explaining the pattern of injury caused by the metallic bodys path, from left frontal lobe to the left cerebellar hemisphere was identified. We presented rare case of penetrating injury of the cranial region caused by non-missile foreign body. cranial injury - non-missile foreign body - autopsy.

Three dimensional live-cell STED microscopy at increased depth using a water immersion objective

NASA Astrophysics Data System (ADS)

Heine, Jörn; Wurm, Christian A.; Keller-Findeisen, Jan; Schönle, Andreas; Harke, Benjamin; Reuss, Matthias; Winter, Franziska R.; Donnert, Gerald

2018-05-01

Modern fluorescence superresolution microscopes are capable of imaging living cells on the nanometer scale. One of those techniques is stimulated emission depletion (STED) which increases the microscope's resolution many times in the lateral and the axial directions. To achieve these high resolutions not only close to the coverslip but also at greater depths, the choice of objective becomes crucial. Oil immersion objectives have frequently been used for STED imaging since their high numerical aperture (NA) leads to high spatial resolutions. But during live-cell imaging, especially at great penetration depths, these objectives have a distinct disadvantage. The refractive index mismatch between the immersion oil and the usually aqueous embedding media of living specimens results in unwanted spherical aberrations. These aberrations distort the point spread functions (PSFs). Notably, during z- and 3D-STED imaging, the resolution increase along the optical axis is majorly hampered if at all possible. To overcome this limitation, we here use a water immersion objective in combination with a spatial light modulator for z-STED measurements of living samples at great depths. This compact design allows for switching between objectives without having to adapt the STED beam path and enables on the fly alterations of the STED PSF to correct for aberrations. Furthermore, we derive the influence of the NA on the axial STED resolution theoretically and experimentally. We show under live-cell imaging conditions that a water immersion objective leads to far superior results than an oil immersion objective at penetration depths of 5-180 μm.

Laser radiography forming bremsstrahlung radiation to image an object

DOEpatents

Perry, Michael D.; Sefcik, Joseph A.

2004-01-13

A method of imaging an object by generating laser pulses with a short-pulse, high-power laser. When the laser pulse strikes a conductive target, bremsstrahlung radiation is generated such that hard ballistic high-energy electrons are formed to penetrate an object. A detector on the opposite side of the object detects these electrons. Since laser pulses are used to form the hard x-rays, multiple pulses can be used to image an object in motion, such as an exploding or compressing object, by using time gated detectors. Furthermore, the laser pulses can be directed down different tubes using mirrors and filters so that each laser pulse will image a different portion of the object.

Optimizing skin protection with semipermeable gloves.

PubMed

Wulfhorst, Britta; Schwanitz, Hans Joachim; Bock, Meike

2004-12-01

Occlusion due to gloves is one important cause of glove irritation. Macerated softened skin gives poor protection against microbes and chemical injuries. The introduction of a breathable protective glove material would represent a significant step toward improved prevention of occupational skin disease. Performance levels of semipermeable and occlusive gloves were examined under conditions typical of the hairdressing profession. In two studies, tests comparing breathable semipermeable gloves to single-use gloves made of occlusive materials were conducted. In an initial study, a user survey was carried out in conjunction with bioengineering examinations. Values at baseline and values after gloves were worn were recorded by measuring transepidermal water loss (TEWL), skin humidity (SH), and skin surface hydrogen ion concentration (pH) in 20 healthy volunteers. In a second study, the gloves were tested for penetrability and permeability with three chemical compounds typically used in the hairdressing profession. Bioengineering examination objectively confirmed users' reports of reduced hand perspiration when semipermeable gloves were worn. The TEWL, SH, and skin surface pH values remained largely stable after 20 minutes of wearing semipermeable gloves, in contrast to the reactions observed with gloves of occlusive materials. Permeability tests indicated that the semipermeable material is effective, with some restrictions. Air leakage testing revealed that all 50 gloves tested were not airtight. Following the optimization of manufacturing methods, additional tests of the penetrability of semipermeable gloves will be necessary.

Ground Penetrating Radar for Measuring Pavement Layer Thickness

DOT National Transportation Integrated Search

2013-01-01

The Utah Department of Transportation (UDOT) implemented and evaluated an advanced traffic signal timing strategy just outside Salt Lake City on the Riverdale Road corridor in Ogden, UT. The objective of the project was to make UDOTs traffic signa...

Static pile load tests on driven piles in Intermediate-Geo Materials : research brief.

DOT National Transportation Integrated Search

2017-02-01

Research Objectives: : Investigate the use of modified standard penetration tests (MSPT) : Compare field results with predictions made by the WisDOT driving formula, PDA and CAPWAP : Improve prediction of pile lengths and pile capacities ...

Digital Mapping of Buried Pipelines with a Dual Array System

DOT National Transportation Integrated Search

2003-06-06

The objective of this research is to develop a non-invasive system for detecting, mapping, and inspecting ferrous and plastic pipelines in place using technology that combines and interprets measurements from ground penetrating radar and electromagne...

Investigation of rf power absorption in the plasma of helicon ion source.

PubMed

Mordyk, S; Alexenko, O; Miroshnichenko, V; Storizhko, V; Stepanov, K; Olshansky, V

2008-02-01

The simulations of the spatial distribution of rf power absorbed in a helicon ion source reveal a correlation between the depth of penetration of rf power into the plasma and the tilt angle of lines of force of the outer magnetic field. The deeper field penetration and greater power absorption were observed at large tilt angles of the field line to the plasma surface. The evaluations as to the possibility of excitation of helicon waves in compact rf ion sources were performed.

Deployable pressurized cell structure for a micrometeoroid detector

NASA Technical Reports Server (NTRS)

Kinard, W. H. (Inventor)

1974-01-01

This disclosure comprises a plurality of individual pressurized cells which are caused to leak in response to a micrometeoroid penetration, the leak being sensed by appropriate instrumentation. The plurality of cells may be rolled into a compact arrangement such that the volume of the micrometeoroid detector is small and therefore readily packed in a payload of a launch vehicle. Once the payload is placed in orbit, the rolled up cells can be released, pressurized and provide a relatively rigid, large surface area for detecting micrometeoroid penetration.

Nonlinear penetration of whistler pulses into collisional plasmas via conductivity modifications

NASA Technical Reports Server (NTRS)

Urrutia, J. M.; Stenzel, R. L.

1991-01-01

A strong electromagnetic impulse (about 0.2 microsec) with central frequency in the whistler-wave regime is applied to a large laboratory plasma dominated by Coulomb collisions. Local electron heating at the antenna and transport along B0 create a channel of high conductivity along which the whistler pulse penetrates with little damping. Because of its rapid temporal evolution, this new form of modulational instability does not involve ducting by density gradients which require ion time scales to develop.

Characterization and Application of a Large Animal Model of Penetrating Ballistic Brain Injury (PBBI)

DTIC Science & Technology

2012-03-01

Jump, South American Track and Field Grand Prix. Cuenca, Ecuador , 2004. - Goodwill Ambassador, Ministry of Tourism of Ecuador . Quito, Ecuador , 2000...they only comprise 11.5% of all-cause injury deaths and have a case fatality rate (CFR) of less than 1% [33]. In contrast, penetrating TBIs due to...because many cases of mild closed TBI are not detected post-injury and because the bodily distribution of wounds for all combat casualties (e.g. Wounded In

Coordinative Voltage Control Strategy with Multiple Resources for Distribution Systems of High PV Penetration: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Xiangqi; Zhang, Yingchen

This paper presents an optimal voltage control methodology with coordination among different voltage-regulating resources, including controllable loads, distributed energy resources such as energy storage and photovoltaics (PV), and utility voltage-regulating devices such as voltage regulators and capacitors. The proposed methodology could effectively tackle the overvoltage and voltage regulation device distortion problems brought by high penetrations of PV to improve grid operation reliability. A voltage-load sensitivity matrix and voltage-regulator sensitivity matrix are used to deploy the resources along the feeder to achieve the control objectives. Mixed-integer nonlinear programming is used to solve the formulated optimization control problem. The methodology has beenmore » tested on the IEEE 123-feeder test system, and the results demonstrate that the proposed approach could actively tackle the voltage problem brought about by high penetrations of PV and improve the reliability of distribution system operation.« less

Experimental and theoretical characterization of deep penetration welding threshold induced by 1-μm laser

NASA Astrophysics Data System (ADS)

Zou, J. L.; He, Y.; Wu, S. K.; Huang, T.; Xiao, R. S.

2015-12-01

The deep penetration-welding threshold (DPWT) is the critical value that describes the welding mode transition from the thermal conduction to the deep penetration. The objective of this research is to clarify the DPWT induced by the lasers with wavelength of 1 μm (1-μm laser), based on experimental observation and theoretical analysis. The experimental results indicated that the DPWT was the ratio between laser power and laser spot diameter (P/d) rather than laser power density (P/S). The evaporation threshold was smaller than the DPWT, while the jump threshold of the evaporated mass flux in the molten pool surface was consistent with the DPWT. Based on the force balance between the evaporation recoil pressure and the surface tension pressure at the gas-liquid interface of the molten pool as well as the temperature field, we developed a self-focusing model, which further confirmed the experimental results.

Predictions penetrate perception: Converging insights from brain, behaviour and disorder

PubMed Central

O’Callaghan, Claire; Kveraga, Kestutis; Shine, James M; Adams, Reginald B.; Bar, Moshe

2018-01-01

It is argued that during ongoing visual perception, the brain is generating top-down predictions to facilitate, guide and constrain the processing of incoming sensory input. Here we demonstrate that these predictions are drawn from a diverse range of cognitive processes, in order to generate the richest and most informative prediction signals. This is consistent with a central role for cognitive penetrability in visual perception. We review behavioural and mechanistic evidence that indicate a wide spectrum of domains—including object recognition, contextual associations, cognitive biases and affective state—that can directly influence visual perception. We combine these insights from the healthy brain with novel observations from neuropsychiatric disorders involving visual hallucinations, which highlight the consequences of imbalance between top-down signals and incoming sensory information. Together, these lines of evidence converge to indicate that predictive penetration, be it cognitive, social or emotional, should be considered a fundamental framework that supports visual perception. PMID:27222169

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution.

PubMed

Oji, Tatsuo; Dornbos, Stephen Q; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the 'agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum . These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

PubMed Central

Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-01-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the ‘agronomic revolution’. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered. PMID:29515908

Recent Advances in Skin Penetration Enhancers for Transdermal Gene and Drug Delivery.

PubMed

Amjadi, Morteza; Mostaghaci, Babak; Sitti, Metin

2017-01-01

There is a growing interest in transdermal delivery systems because of their noninvasive, targeted, and on-demand delivery of gene and drugs. However, efficient penetration of therapeutic compounds into the skin is still challenging largely due to the impermeability of the outermost layer of the skin, known as stratum corneum. Recently, there have been major research activities to enhance the skin penetration depth of pharmacological agents. This article reviews recent advances in the development of various strategies for skin penetration enhancement. We show that approaches such as ultrasound waves, laser, and microneedle patches have successfully been employed to physically disrupt the stratum corneum structure for enhanced transdermal delivery. Rather than physical approaches, several non-physical route have also been utilized for efficient transdermal delivery across the skin barrier. Finally, we discuss some clinical applications of transdermal delivery systems for gene and drug delivery. This paper shows that transdermal delivery devices can potentially function for diverse healthcare and medical applications while further investigations are still necessary for more efficient skin penetration of gene and drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

NASA Astrophysics Data System (ADS)

Oji, Tatsuo; Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the `agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

Microvascular basis for growth of small infarcts following occlusion of single penetrating arterioles in mouse cortex

PubMed Central

Taylor, Zachary J; Hui, Edward S; Watson, Ashley N; Nie, Xingju; Deardorff, Rachael L; Jensen, Jens H; Helpern, Joseph A

2015-01-01

Small cerebral infarcts, i.e. microinfarcts, are common in the aging brain and linked to vascular cognitive impairment. However, little is known about the acute growth of these minute lesions and their effect on blood flow in surrounding tissues. We modeled microinfarcts in the mouse cortex by inducing photothrombotic clots in single penetrating arterioles. The resultant hemodynamic changes in tissues surrounding the occluded vessel were then studied using in vivo two-photon microscopy. We were able to generate a spectrum of infarct volumes by occluding arterioles that carried a range of blood fluxes. Those resulting from occlusion of high-flux penetrating arterioles (flux of 2 nL/s or higher) exhibited a radial outgrowth that encompassed unusually large tissue volumes. The gradual expansion of these infarcts was propagated by an evolving insufficiency in capillary flow that encroached on territories of neighboring penetrating arterioles, leading to the stagnation and recruitment of their perfusion domains into the final infarct volume. Our results suggest that local collapse of microvascular function contributes to tissue damage incurred by single penetrating arteriole occlusions in mice, and that a similar mechanism may add to pathophysiology induced by microinfarcts of the human brain. PMID:26661182

The effect of longitudinal conductance variations on the ionospheric prompt penetration electric fields

NASA Astrophysics Data System (ADS)

Sazykin, S.; Wolf, R.; Spiro, R.; Fejer, B.

Ionospheric prompt penetration electric fields of magnetospheric origin, together with the atmospheric disturbance dynamo, represent the most important parameters controlling the storm-time dynamics of the low and mid-latitude ionosphere. These prompt penetration fields result from the disruption of region-2 field-aligned shielding currents during geomagnetically disturbed conditions. Penetration electric fields con- trol, to a large extent, the generation and development of equatorial spread-F plasma instabilities as well as other dynamic space weather phenomena in the ionosphere equatorward of the auroral zone. While modeling studies typically agree with average patterns of prompt penetration fields, experimental results suggest that longitudinal variations of the ionospheric con- ductivities play a non-negligible role in controlling spread-F phenomena, an effect that has not previously been modeled. We present first results of modeling prompt pene- tration electric fields using a version of the Rice Convection Model (RCM) that allows for longitudinal variations in the ionospheric conductance tensor. The RCM is a first- principles numerical ionosphere-magnetosphere coupling model that solves for the electric fields, field-aligned currents, and particle distributions in the ionosphere and inner/middle magnetosphere. We compare these new theoretical results with electric field observations.

Synergistic Skin Penetration Enhancer and Nanoemulsion Formulations Promote the Human Epidermal Permeation of Caffeine and Naproxen.

PubMed

Abd, Eman; Namjoshi, Sarika; Mohammed, Yousuf H; Roberts, Michael S; Grice, Jeffrey E

2016-01-01

We examined the extent of skin permeation enhancement of the hydrophilic drug caffeine and lipophilic drug naproxen applied in nanoemulsions incorporating skin penetration enhancers. Infinite doses of fully characterized oil-in-water nanoemulsions containing the skin penetration enhancers oleic acid or eucalyptol as oil phases and caffeine (3%) or naproxen (2%) were applied to human epidermal membranes in Franz diffusion cells, along with aqueous control solutions. Caffeine and naproxen fluxes were determined over 8 h. Solute solubility in the formulations and in the stratum corneum (SC), as well as the uptake of product components into the SC were measured. The nanoemulsions significantly enhanced the skin penetration of caffeine and naproxen, compared to aqueous control solutions. Caffeine maximum flux enhancement was associated with a synergistic increase in both caffeine SC solubility and skin diffusivity, whereas a formulation-increased solubility in the SC was the dominant determinant for increased naproxen fluxes. Enhancements in SC solubility were related to the uptake of the formulation excipients containing the active compounds into the SC. Enhanced skin penetration in these systems is largely driven by uptake of formulation excipients containing the active compounds into the SC with impacts on SC solubility and diffusivity.

HMO growth and the geographical redistribution of generalist and specialist physicians, 1987-1997.

PubMed Central

Escarce, J J; Polsky, D; Wozniak, G D; Kletke, P R

2000-01-01

OBJECTIVE: To assess the impact of the growth in HMO penetration in different metropolitan areas on the change in the number of generalists, specialists, and total physicians, and on the change in the proportion of physicians who are generalists. DATA SOURCES/STUDY SETTING: The American Medical Association Physician Masterfile, to obtain the number of patient care generalists and specialists in 1987 and in 1997 who were practicing in each of 316 metropolitan areas in the United States. Additional data for each metropolitan area were obtained from a variety of sources, and included HMO penetration in 1986 and 1996. STUDY DESIGN: We estimated multivariate regression models in which the change in the number of physicians between 1987 and 1997 was a function of HMO penetration in 1986, the change in HMO penetration between 1986 and 1996, population characteristics and physician fees in 1986, and the change in population characteristics and fees between 1986 and 1996. Each model was estimated using ordinary least squares (OLS) and two-stage least squares (TSLS). PRINCIPAL FINDINGS: HMO penetration did not affect the number of generalist physicians or hospital-based specialists, but faster HMO growth led to smaller increases in the numbers of medical/surgical specialists and total physicians. Faster HMO growth also led to larger increases in the proportion of physicians who were generalists. Our best estimate is that an increase in HMO penetration of .10 between 1986 and 1996 reduced the rate of increase in medical/surgical specialists by 10.3 percent and reduced the rate of increase in total physicians by 7.2 percent. CONCLUSIONS: The findings of this study support the notion that HMOs reduce the demand for physician services, particularly for specialists' services. The findings also imply that, during the past decade, there has been a redistribution of physicians-especially medical/surgical specialists-from metropolitan areas with high HMO penetration to low-penetration areas. PMID:11055451

Diffusion of beta-lactam antibiotics through the porin channels of Escherichia coli K-12.

PubMed Central

Yoshimura, F; Nikaido, H

1985-01-01

Diffusion rates of various beta-lactam antibiotics through the OmpF and OmpC porin channels of Escherichia coli K-12 were measured by the use of reconstituted proteoliposomes. The results can be interpreted on the basis of the gross physicochemical properties of the antibiotics along the following lines. (i) As noted previously (Nikaido et al., J. Bacteriol., 153:232-240, 1983), there was a monotonous dependence of the penetration rate on the hydrophobicity of the molecule among the classical monoanionic beta-lactams, and a 10-fold increase in the octanol-water partition coefficient of the uncharged molecule decreased the penetration rate by a factor of 5 to 6. (ii) Compounds with exceptionally bulky side chains, such as mezlocillin, piperacillin, and cefoperazone, showed much slower penetration rates than expected from their hydrophobicity. (iii) The substituted oxime side chain on the alpha-carbon of the substituent group at position 7 of the cephem nucleus decreased the penetration rate almost by an order of magnitude; this appears to be largely due to the steric effect. (iv) The presence of a methoxy group at position 7 of the cephalosporins also reduced the penetration rate by 20%, probably also due to the steric hindrance. (v) Zwitterionic compounds penetrated very rapidly, and the correlation between the rate and hydrophobicity appeared to be much weaker than with the monoanionic compounds. Imipenem showed the highest permeability among the compounds tested, presumably due, at least in part, to its compact molecular structure. (vi) Compounds with two negative charges penetrated more slowly than did analogs with only one negatively charged group. Among them, only moxalactam, ceftriaxone, and azthreonam showed penetration rates corresponding to, or higher than, 10% of that of imipenem. PMID:2580479

Subsurface polarimetric migration imaging for full polarimetric ground-penetrating radar

NASA Astrophysics Data System (ADS)

Feng, Xuan; Yu, Yue; Liu, Cai; Fehler, Michael

2015-08-01

Polarization is a property of electromagnetic wave that generally refers to the locus of the electric field vector, which can be used to characterize surface properties by polarimetric radar. However, its use has been less common in the ground-penetrating radar (GPR) community. Full polarimetric GPR data include scattering matrices, by which the polarization properties can be extracted, at each survey point. Different components of the measured scattering matrix are sensitive to different types of subsurface objects, which offers a potential improvement in the detection ability of GPR. This paper develops a polarimetric migration imaging method. By merging the Pauli polarimetric decomposition technique with the Krichhoff migration equation, we develop a polarimetric migration algorithm, which can extract three migrated coefficients that are sensitive to different types of objects. Then fusing the three migrated coefficients, we can obtain subsurface colour-coded reconstructed object images, which can be employed to interpret both the geometrical information and the scattering mechanism of the subsurface objects. A 3-D full polarimetric GPR data set was acquired in a laboratory experiment and was used to test the method. In the laboratory experiment, four objects-a scatterer, a ball, a plate and a dihedral target-were buried in homogeneous dry sand under a flat ground surface. By merging the reconstructed image with polarization properties, we enhanced the subsurface image and improved the classification ability of GPR.

Modelling the effects of penetrance and family size on rates of sporadic and familial disease.

PubMed

Al-Chalabi, Ammar; Lewis, Cathryn M

2011-01-01

Many complex diseases show a diversity of inheritance patterns ranging from familial disease, manifesting with autosomal dominant inheritance, through to simplex families in which only one person is affected, manifesting as apparently sporadic disease. The role of ascertainment bias in generating apparent patterns of inheritance is often overlooked. We therefore explored the role of two key parameters that influence ascertainment, penetrance and family size, in rates of observed familiality. We develop a mathematical model of familiality of disease, with parameters for penetrance, mutation frequency and family size, and test this in a complex disease: amyotrophic lateral sclerosis. Monogenic, high-penetrance variants can explain patterns of inheritance in complex diseases and account for a large proportion of those with no apparent family history. With current demographic trends, rates of familiality will drop further. For example, a variant with penetrance 0.5 will cause apparently sporadic disease in 12% of families of size 10, but 80% of families of size 1. A variant with penetrance 0.9 has only an 11% chance of appearing sporadic in families of a size similar to those of Ireland in the past, compared with 57% in one-child families like many in China. These findings have implications for genetic counselling, disease classification and the design of gene-hunting studies. The distinction between familial and apparently sporadic disease should be considered artificial. Copyright © 2011 S. Karger AG, Basel.

Mechanical Energy Propagation and Backscattering in Nominally Dry Soil: Imaging Buried Land Mines

NASA Astrophysics Data System (ADS)

Sen, Surajit

2003-04-01

The imaging of shallow buried objects in a complex medium, e.g., nominally dry sand, is an outstanding challenge. Such imaging is of relevance in connection with the detection and subsequent imaging of buried non-metallic anti-personnel land mines and in other applications. It has been shown that gentle mechanical impulses and low frequency sound waves with frequencies roughly between 150-350 Hz or so can penetrate distances of up to a foot in sand. Hence, such signals can potentially be useful in the detection and perhaps in the imaging of shallow buried objects. It is presently unclear whether high frequency signals can be effectively used to image shallow buried objects. Impulses can typically penetrate larger distances into sand and soil. Both impulses and continuous sound waves can be used for imaging shallow buried objects. The talk shall briefly review the state-of-the-art in low frequency sound propagation in soil and shall discuss the current understanding of impulse propagation and backscattering in nominally dry sand beds. It will be argued that impulse based imaging may have the potential to be a simple and fast way to detect and image small non-metallic mines. Research supported by the National Science Foundation Grant No. NSF-CMS 0070055.

Confocal Imaging of the Embryonic Heart: How Deep?

NASA Astrophysics Data System (ADS)

Miller, Christine E.; Thompson, Robert P.; Bigelow, Michael R.; Gittinger, George; Trusk, Thomas C.; Sedmera, David

2005-06-01

Confocal microscopy allows for optical sectioning of tissues, thus obviating the need for physical sectioning and subsequent registration to obtain a three-dimensional representation of tissue architecture. However, practicalities such as tissue opacity, light penetration, and detector sensitivity have usually limited the available depth of imaging to 200 [mu]m. With the emergence of newer, more powerful systems, we attempted to push these limits to those dictated by the working distance of the objective. We used whole-mount immunohistochemical staining followed by clearing with benzyl alcohol-benzyl benzoate (BABB) to visualize three-dimensional myocardial architecture. Confocal imaging of entire chick embryonic hearts up to a depth of 1.5 mm with voxel dimensions of 3 [mu]m was achieved with a 10× dry objective. For the purpose of screening for congenital heart defects, we used endocardial painting with fluorescently labeled poly-L-lysine and imaged BABB-cleared hearts with a 5× objective up to a depth of 2 mm. Two-photon imaging of whole-mount specimens stained with Hoechst nuclear dye produced clear images all the way through stage 29 hearts without significant signal attenuation. Thus, currently available systems allow confocal imaging of fixed samples to previously unattainable depths, the current limiting factors being objective working distance, antibody penetration, specimen autofluorescence, and incomplete clearing.

31P Solid-state NMR based monitoring of permeation of cell penetrating peptides into skin

PubMed Central

Desai, Pinaki R.; Cormier, Ashley R.; Shah, Punit P.; Patlolla, Ram R.; Paravastu, Anant K.; Singh, Mandip

2013-01-01

The main objective of the current study was to investigate penetration of cell penetrating peptides (CPPs: TAT, R8, R11 and YKA) through skin intercellular lipids using 31P magic angle spinning (MAS) solid-state NMR. In vitro skin permeation studies were performed on rat skin, sections (0–60, 61–120 and 121–180 µm) were collected and analyzed for 31P NMR signal. The concentration dependent shift of 0, 25, 50, 100 and 200 mg/ml of TAT on skin layers, diffusion of TAT, R8, R11 and YKA in the skin and time dependent permeation of R11 was measured on various skin sections using 31P solid-state NMR. Further, CPPs and CPP-tagged fluorescent dye encapsulate liposomes (FLip) in skin layers were tagged using confocal microscopy. The change in 31P NMR chemical shift was found to depend monotonically on the amount of CPP applied on skin, with saturation behavior above 100 mg/ml CPP concentration. R11 and TAT caused more shift in solid-state NMR peaks compared to other peptides. Furthermore, NMR spectra showed R11 penetration up to 180 µm within 30 min. The results of the solid-state NMR study were in agreement with confocal microscopy studies. Thus, 31P solid-state NMR can be used to track CPP penetration into different skin layers. PMID:23702274

HMO penetration, competition, and risk-adjusted hospital mortality.

PubMed

Mukamel, D B; Zwanziger, J; Tomaszewski, K J

2001-12-01

HMOs have been shown to have an effect on the care provided directly to their enrollees. They may also influence the care provided to individuals in fee-for-service plans through a spill-over effect. The objective of this study was to investigate the associations among HMO market penetration, HMO and hospital competition, and the quality of care received by Medicare fee-for-service patients measured by risk-adjusted hospital mortality rates. The 1990 data for 1,927 hospitals in 134 metropolitan statistical areas (with five or more hospitals) included Medicare fee-for-service risk-adjusted mortality rates from the Medicare Hospital Information Reports, hospital characteristics from the American Hospital Association annual survey, and HMO market penetration and competition calculated from InterStudy and Group Health Association of America data. Statistical regression techniques were used to identify the associations between HMO market penetration, competition, and risk-adjusted mortality, controlling for other hospital characteristics and region. Higher HMO market penetration and to a lesser degree increased HMO competition were associated with better mortality outcomes for fee-for-service Medicare enrollees. Competition between hospitals did not exhibit a significant association. HMOs may have a spill-over effect on quality of care received by individuals enrolled in fee-for-service plans. These findings may be explained by a positive effect on local practice styles or a preferential selection by HMOs for areas with better hospital care.

Analysis of the convective evaporation of nondilute clusters of drops

NASA Technical Reports Server (NTRS)

Bellan, J.; Harstad, K.

1987-01-01

The penetration distance of an outer flow into a drop cluster volume is the critical, evaporation mode-controlling parameter in the present model for nondilute drop clusters' convective evaporation. The model is found to perform well for such low penetration distances as those obtained for dense clusters in hot environments and low relative velocities between the outer gases and the cluster. For large penetration distances, however, the predictive power of the model deteriorates; in addition, the evaporation time is found to be a weak function of the initial relative velocity and a strong function of the initial drop temperature. The results generally show that the interior drop temperature was transient throughout the drop lifetime, although temperature nonuniformities persisted up to the first third of the total evaporation time at most.

Heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.

PubMed

Patel, Kashyap A; Kettunen, Jarno; Laakso, Markku; Stančáková, Alena; Laver, Thomas W; Colclough, Kevin; Johnson, Matthew B; Abramowicz, Marc; Groop, Leif; Miettinen, Päivi J; Shepherd, Maggie H; Flanagan, Sarah E; Ellard, Sian; Inagaki, Nobuya; Hattersley, Andrew T; Tuomi, Tiinamaija; Cnop, Miriam; Weedon, Michael N

2017-10-12

Finding new causes of monogenic diabetes helps understand glycaemic regulation in humans. To find novel genetic causes of maturity-onset diabetes of the young (MODY), we sequenced MODY cases with unknown aetiology and compared variant frequencies to large public databases. From 36 European patients, we identify two probands with novel RFX6 heterozygous nonsense variants. RFX6 protein truncating variants are enriched in the MODY discovery cohort compared to the European control population within ExAC (odds ratio = 131, P = 1 × 10 -4 ). We find similar results in non-Finnish European (n = 348, odds ratio = 43, P = 5 × 10 -5 ) and Finnish (n = 80, odds ratio = 22, P = 1 × 10 -6 ) replication cohorts. RFX6 heterozygotes have reduced penetrance of diabetes compared to common HNF1A and HNF4A-MODY mutations (27, 70 and 55% at 25 years of age, respectively). The hyperglycaemia results from beta-cell dysfunction and is associated with lower fasting and stimulated gastric inhibitory polypeptide (GIP) levels. Our study demonstrates that heterozygous RFX6 protein truncating variants are associated with MODY with reduced penetrance.Maturity-onset diabetes of the young (MODY) is the most common subtype of familial diabetes. Here, Patel et al. use targeted DNA sequencing of MODY patients and large-scale publically available data to show that RFX6 heterozygous protein truncating variants cause reduced penetrance MODY.

Relationship between cloud-to-ground discharge and penetrative clouds: A multi-channel satellite application

NASA Astrophysics Data System (ADS)

Machado, Luiz A. T.; Lima, Wagner F. A.; Pinto, Osmar; Morales, Carlos A.

This work presents a relationship between atmospheric cloud-to-ground discharges and penetrative convective clouds. It combines Infrared and Water Vapor channels from the GOES-12 geostationary satellite with cloud-to-ground discharge data from the Brazilian Integrated Lightning Detection Network (RINDAT) during the period from January to February 2005. The difference between water vapor and infrared brightness temperature is a tracer penetrating clouds. Due to the water vapor channel's strong absorption, this difference is positive only during overshooting cases, when convective clouds penetrate the stratosphere. From this difference and the cloud-to-ground, discharge measured on the ground by RINDAT, it was possible to adjust exponential curves that relate the brightness temperature difference from these two channels to the probability of occurrence of cloud-to-ground discharges, with a very large coefficient of determination. If WV-IR brightness temperature difference is greater than - 15 K there is a large potential for cloud-to-ground discharge activity. As this difference increases the cloud-to-ground discharge probably increases, for example: if this difference is equal to zero, the probability of having at least one cloud-to-ground discharge is 10.9%, 7.0% for two, 4.4% for four, 2.7% for eight and 1.5% for sixteen cloud-to-ground discharges. Through this process, was developed a scheme that estimates the probability of occurrence of cloud-to-ground discharge over all the continental region of South America.

Drug carrier nanoparticles that penetrate human chronic rhinosinusitis mucus

PubMed Central

Lai, Samuel K.; Suk, Jung Soo; Pace, Amanda; Wang, Ying-Ying; Yang, Ming; Mert, Olcay; Chen, Jeane; Kim, Jean; Hanes, Justin

2011-01-01

No effective therapies currently exist for chronic rhinosinusitis (CRS), a persistent inflammatory condition characterized by the accumulation of highly viscoelastic mucus (CRSM) in the sinuses. Nanoparticle therapeutics offer promise for localized therapies for CRS, but must penetrate CRSM in order to avoid washout during sinus cleansing and to reach underlying epithelial cells. Prior research has not established whether nanoparticles can penetrate the tenacious CRSM barrier, or instead become trapped. Here, we first measured the diffusion rates of polystyrene nanoparticles and the same nanoparticles modified with muco-inert polyethylene glycol (PEG) coatings in fresh, minimally perturbed CRSM collected during endoscopic sinus surgery from CRS patients with and without nasal polyp. We found that uncoated polystyrene particles, previously shown to be mucoadhesive, were immobilized in all CRSM samples tested. In contrast, densely PEGylated particles as large as 200 nm were able to readily penetrate all CRSM samples from patients with CRS alone, and nearly half of CRSM samples from patients with nasal polyp. Based on the mobility of different sized PEGylated particles, we estimate the average pore size of fresh CRSM to be at least 150 ± 50 nm. Guided by these studies, we formulated mucus-penetrating particles (MPP) composed of PLGA and Pluronics, two materials with a long history of safety and use in humans. We showed that biodegradable MPP are capable of rapidly penetrating CRSM at average speeds up to only 20-fold slower than their theoretical speeds in water. Our findings strongly support the development of mucus-penetrating nanomedicines for the treatment of CRS. PMID:21665271

Use of the SAR (Synthetic Aperture Radar) P band for detection of the Moche and Lambayeque canal networks in the Apurlec region, Perù

NASA Astrophysics Data System (ADS)

Ilaria Pannaccione Apa, Maria; Santovito, Maria Rosaria; Pica, Giulia; Catapano, Ilaria; Fornaro, Gianfranco; Lanari, Riccardo; Soldovieri, Francesco; Wester La Torre, Carlos; Fernandez Manayalle, Marco Antonio; Longo, Francesco; Facchinetti, Claudia; Formaro, Roberto

2016-04-01

In recent years, research attention has been devoted to the development of a new class of airborne radar systems using low frequency bands ranging from VHF/UHF to P and L ones. In this frame, the Italian Space Agency (ASI) has promoted the development of a new multi-mode and multi-band airborne radar system, which can be considered even a "proof-of-concept" for the next space-borne missions. In particular, in agreement with the ASI, the research consortium CO.RI.S.T.A. has in charge the design, development and flight validation of such a kind of system, which is the first airborne radar entirely built in Italy. The aim was to design and realize a radar system able to work in different modalities as: nadir-looking sounder at VHF band (163 MHz); side-looking imager (SAR) at P band with two channels at 450 MHz and 900 MHz. The P-band is a penetration radar. Exploiting penetration features of low frequency electromagnetic waves, dielectric discontinuities of observed scene due to inhomogeneous materials rise up and can be detected on the resulting image. Therefore buried objects or targets placed under vegetation may be detected. Penetration capabilities essentially depend on microwave frequency. Typically, penetration distance is inversely proportional to microwave frequency. The higher the frequency, the lower the penetration depth. Terrain characteristics affect penetration capabilities. Humidity acts as a shield to microwave penetration. Hence terrain with high water content are not good targets for P-band applicability. Science community, governments and space agencies have increased their interest about low frequency radar for their useful applicability in climatology, ecosystem monitoring, glaciology, archaeology. The combination of low frequency and high relative bandwidth of such a systems has a large applicability in both military and civilian applications, ranging from forestry applications, biomass measuring, archaeological and geological exploration, glaciers investigation, biomass monitoring, detection of buried targets. Its extension to non-civil application concerns sub-surface target detection and foliage penetration (FOPEN). In order to achieve the flexibility to face all the above mentioned fields of application, the CORISTA system has been designed as a multi-mode and multi-frequency radar. Multimode stands for the functionality of the system both as Sounder and Imager. In addition, P-band radar is a multi-frequency instrument, since it is designed to work in three different frequency bands, as mentioned above: lower frequency band is used in sounder operative mode, higher frequency in imager operative mode. In the Imager operative mode, low resolution and high resolution capabilities are implemented. The data collected by the radar system have been processed using a model-based microwave tomographic approach, recently developed by IREA-CNR, with the aim to enhance the interpretability of the raw-data radar images. Currently, the non-invasive SAR P band application is under evaluation for testing in the Northern Coast of Perù, in collaboration with the Museo Arqueológico Nacional Brüning. The project will aim to recognize the subsurface ancient Moche (100-700 d.C.) and Lambayeque (700-1375 d.C.) canal networks, whose water supply comes from the Canal Taymi, started to be dug by the Mochicas, still in use by local communities.

The Current Status of the Japanese Penetrator Mission: LUNAR-A

NASA Astrophysics Data System (ADS)

Tanaka, S.; Shiraishi, H.; Fujimura, A.; Hayakawa, H.

The scientific objective of the LUNAR-A, Japanese Penetrator Mission, is to explore the lunar interior by seismic and heat-flow experiments. Two penetrators containing two seismometers (horizontal and vertical components) and heat-flow probes will be deployed from a spacecraft onto the lunar surface, one on the nearside and the other on the farside of the moon. The final impact velocity of the penetrator will be about 300m/sec; it will encounter a shock of about 8000 G at impact on the lunar surface. According to numerous experimental impact tests using model penetrators and a lunar regolith analog target, each penetrator is predicted to penetrate to a depth of 1 to 3 m. The data obtained by the penetrators will be transmitted to the earth station via the LUNAR-A mother spacecraft orbiting at an altitude of about 200 km. The penetrator is a missile-shaped instrument carrier, which is about 14cm in diameter, 75cm in length, and about 14kg in weight without attitude control system. It contains a two-component seismometer and heat flow probes together with other supporting instruments such as a tilt meter and an accelerometer. The seismic observations are expected to provide key data on the size of the lunar core, as well as data on deep lunar mantle structure. The heat flow measurements at two penetrator deployment sites will also provide important data on the thermal structure and bulk concentrations of heat-generating elements in the Moon. These data will provide much stronger geophysical constraints on the origin and evolution of the Moon than has been obtained so far. The LUNAR-A spacecraft was supposed to be launched in the summer of 2004, but it was postponed due to the necessity of a replacement of the valves used in the RCS propulsion system of the spacecraft, following a recall issued by the manufacturer who found a malfunction of similar valves. Then, the technological review boards by ISAS and JAXA recommended that both the more robustness of the communication link, between the penetrator and the orbiting spacecraft, and the improvement of data processing unit onboard penetrator should be made. And also, in compliance with the recommendation by the external review board, we have made a decision to suspend a development of LUNAR-A spacecraft and to concentrate on the completion of the penetrator technology. To solve the above technological issues, it was estimated to take a couple of years. In this paper, we present the current status of development and some results of the impact tests for component level models and for the full-size integrated model, which both are modified and re-designed.

Tests of protective clothing for the safe handling of pressurized lamps

NASA Technical Reports Server (NTRS)

Ewashinka, J. G.

1975-01-01

Tests were made to find a clothing material combination for use in handling high-pressure lamps. Monofilament nylon, ballistic nylon, and ballistic felt grouped into various multilayer combinations and chromed leather were positioned around and 30 cm (12 in.) away from exploding high-pressure lamps of different manufacturers and wattages. The results are: (1) 5024 nylon/ballistic felt/5024 nylon in a layered configuration was not penetrated by fragments of lamps as large as 6.5 kW; (2) this layered combination is lightweight and pliable and offers greater mobility and comfort to the user than previous protective clothing; and (3) Lexan plastic 1.6 mm (1/6 in.) thick to be used for face shield material showed no penetration for lamps as large as 20 kW.

Knife wound to the posterior fossa in a child.

PubMed

Mohan, Avinash L; Slim, Michel; Benzil, Deborah L

2005-03-01

Knife wounds to the posterior fossa are a rare occurrence, especially in children. We report an 8-year-old girl who sustained a penetrating knife injury through the occipital bone into the posterior fossa. On presentation, the large knife blade was firmly embedded in her head. Radiographic evaluation was limited to plain X-rays because of the large size and sharpness of the embedded blade. Innovative positioning was used during intubation and then the patient was positioned semi-prone on the operating room table. The blade was surgically removed and the dura was closed. Atypical penetrating cranial injuries in children may require the treatment team to take a creative approach to the evaluation and repair of the lesion in order to maximize patient safety and minimize the risk of neurological injury.

Meteorite and meteoroid: New comprehensive definitions

USGS Publications Warehouse

Rubin, A.E.; Grossman, J.N.

2010-01-01

Meteorites have traditionally been defined as solid objects that have fallen to Earth from space. This definition, however, is no longer adequate. In recent decades, man-made objects have fallen to Earth from space, meteorites have been identified on the Moon and Mars, and small interplanetary objects have impacted orbiting spacecraft. Taking these facts and other potential complications into consideration, we offer new comprehensive definitions of the terms "meteorite,""meteoroid," and their smaller counterparts: A meteoroid is a 10-??m to 1-m-size natural solid object moving in interplanetary space. A micrometeoroid is a meteoroid 10 ??m to 2 mm in size. A meteorite is a natural, solid object larger than 10 ??m in size, derived from a celestial body, that was transported by natural means from the body on which it formed to a region outside the dominant gravitational influence of that body and that later collided with a natural or artificial body larger than itself (even if it is the same body from which it was launched). Weathering and other secondary processes do not affect an object's status as a meteorite as long as something recognizable remains of its original minerals or structure. An object loses its status as a meteorite if it is incorporated into a larger rock that becomes a meteorite itself. A micrometeorite is a meteorite between 10 ??m and 2 mm in size. Meteorite- "a solid substance or body falling from the high regions of the atmosphere" (Craig 1849); "[a] mass of stone and iron that ha[s] been directly observed to have fallen down to the Earth's surface" (translated from Cohen 1894); "[a] solid bod[y] which came to the earth from space" (Farrington 1915); "A mass of solid matter, too small to be considered an asteroid; either traveling through space as an unattached unit, or having landed on the earth and still retaining its identity" (Nininger 1933); "[a meteoroid] which has reached the surface of the Earth without being vaporized" (1958 International Astronomical Union (IAU) definition, quoted by Millman 1961); "a solid body which has arrived on the Earth from outer space" (Mason 1962); "[a] solid bod[y] which reach[es] the Earth (or the Moon, Mars, etc.) from interplanetary space and [is] large enough to survive passage through the Earth's (or Mars', etc.) atmosphere" (Gomes and Keil 1980); "[a meteoroid] that survive[s] passage through the atmosphere and fall[s] to earth" (Burke 1986); "a recovered fragment of a meteoroid that has survived transit through the earth's atmosphere" (McSween 1987); "[a] solid bod[y] of extraterrestrial material that penetrate[s] the atmosphere and reach[es] the Earth's surface" (Krot et al. 2003). ?? The Meteoritical Society, 2010.

[Application of single-band brightness variance ratio to the interference dissociation of cloud for satellite data].

PubMed

Qu, Wei-ping; Liu, Wen-qing; Liu, Jian-guo; Lu, Yi-huai; Zhu, Jun; Qin, Min; Liu, Cheng

2006-11-01

In satellite remote-sensing detection, cloud as an interference plays a negative role in data retrieval. How to discern the cloud fields with high fidelity thus comes as a need to the following research. A new method rooting in atmospheric radiation characteristics of cloud layer, in the present paper, presents a sort of solution where single-band brightness variance ratio is used to detect the relative intensity of cloud clutter so as to delineate cloud field rapidly and exactly, and the formulae of brightness variance ratio of satellite image, image reflectance variance ratio, and brightness temperature variance ratio of thermal infrared image are also given to enable cloud elimination to produce data free from cloud interference. According to the variance of the penetrating capability for different spectra bands, an objective evaluation is done on cloud penetration of them with the factors that influence penetration effect. Finally, a multi-band data fusion task is completed using the image data of infrared penetration from cirrus nothus. Image data reconstruction is of good quality and exactitude to show the real data of visible band covered by cloud fields. Statistics indicates the consistency of waveband relativity with image data after the data fusion.

Effect of 1,4-cyclohexanediol on percutaneous absorption and penetration of azelaic acid.

PubMed

Li, Nan; Su, Qian; Tan, Fengping; Zhang, Jerry

2010-03-15

The objective of this study is to investigate the effect of 1,4-cyclohexanediol as a retardant on the percutaneous absorption and penetration of azelaic acid. Hairless rat skin was mounted on Franz diffusion cells and treated with topical formulations containing solubilized azelaic acid with and without 1,4-cyclohexanediol. The skin was separated into stratum corneum and the deeper skin layers. The azelaic acid collected in receptor medium and each layer at the end of each time point was extracted and quantified. A significant decrease in flux across the skin suggests a penetration retardation effect of 1,4-cyclohexanediol (42.50 microg/cm(2)/h in the presence of vs. 76.25 microg/cm(2)/h in the absence of) at active loading level of 1.13 mg/cm(2). The penetration retardation effect was also observed at higher active loading level (2.82 mg/cm(2)). Furthermore, presence of 1,4-cyclohexanediol in the topical formulation did not reduce the skin and epidermal retention of azelaic acid, suggesting its potential use in the development of superior topical formation for reducing potential systematic side effect while maintaining therapeutic efficiency. 2009 Elsevier B.V. All rights reserved.

Analyses on Cost Reduction and CO2 Mitigation by Penetration of Fuel Cells to Residential Houses

NASA Astrophysics Data System (ADS)

Aki, Hirohisa; Yamamoto, Shigeo; Kondoh, Junji; Murata, Akinobu; Ishii, Itaru; Maeda, Tetsuhiko

This paper presents analyses on the penetration of polymer electrolyte fuel cells (PEFC) into a group of 10 residential houses and its effects of CO2 emission mitigation and consumers’ cost reduction in next 30 years. The price is considered to be reduced as the penetration progress which is expected to begin in near future. An experimental curve is assumed to express the decrease of the price. Installation of energy interchange systems which involve electricity, gas and hydrogen between a house which has a FC and contiguous houses is assumed to utilize both electricity and heat more efficiently, and to avoid start-stop operation of fuel processor (reformer) as much as possible. A multi-objective model which considers CO2 mitigation and consumers’ cost reduction is constructed and provided a Pareto optimum solution. A solution which simultaneously realizes both CO2 mitigation and consumers’ cost reduction appeared in the Pareto optimum solution. Strategies to reduce CO2 emission and consumers’ cost are suggested from the results of the analyses. The analyses also revealed that the energy interchange systems are effective especially in the early stage of the penetration.

Integration of real time kinematic satellite navigation with ground-penetrating radar surveys

USDA-ARS?s Scientific Manuscript database

Precision agriculture, environmental mapping, and construction benefit from subsurface imaging by revealing the spatial variability of underground features. Features surveyed of agricultural interest are bedrock depth, soil horizon thicknesses, and buried–object features such as drainage pipe. For t...

Preface–JES focus issue on electrolysis for increased renewable energy penetration

DOE PAGES

Pivovar, B.; Carmo, M.; Ayers, K.; ...

2016-10-22

The objective here of this special issue is to help identify the leading research being performed in the electrolysis area and provide context for the electrolysis advances that will be required for a larger role in tomorrow's energy system.

Evaluation of consolidation characteristics of cohesive soils from piezocone penetration tests : technical summary.

DOT National Transportation Integrated Search

2004-07-01

The main objective of this study was to evaluate the current interpretation methods for their capability to reasonably predict the consolidation parameters needed to estimate the magnitude and time rate of consolidation settlement in fine-grained soi...

2015 electric vehicle market summary and barriers.

DOT National Transportation Integrated Search

2016-06-01

The object of this research report is to present the current market status of plug-in-electric : vehicles (PEVs) and to predict their future penetration within the world and U.S. markets. The : sales values for 2015 show that China leads in yearly sa...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Mingjian; Zhang, Jie; Feng, Cong

Here, one of the biggest concerns associated with integrating a large amount of renewable energy into the power grid is the ability to handle large ramps in the renewable power output. For the sake of system reliability and economics, it is essential for power system operators to better understand the ramping features of renewable, load, and netload. An optimized swinging door algorithm (OpSDA) is used and extended to accurately and efficiently detect ramping events. For wind power ramps detection, a process of merging 'bumps' (that have a different changing direction) into adjacent ramping segments is included to improve the performancemore » of the OpSDA method. For solar ramps detection, ramping events that occur in both clear-sky and measured (or forecasted) solar power are removed to account for the diurnal pattern of solar generation. Ramping features are extracted and extensively compared between load and netload under different renewable penetration levels (9.77%, 15.85%, and 51.38%). Comparison results show that (i) netload ramp events with shorter durations and smaller magnitudes occur more frequently when renewable penetration level increases, and the total number of ramping events also increases; and (ii) different ramping characteristics are observed in load and netload even with a low renewable penetration level.« less

Predicting Boat-Generated Wave Heights: A Quantitative Analysis through Video Observations of Vessel Wakes

DTIC Science & Technology

2012-05-18

by the AWAC. It is a surface- penetrating device that measures continuous changes in the water elevations over time at much higher sampling rates of...background subtraction, a technique based on detecting change from a background scene. Their study highlights the difficulty in object detection and tracking...movements (Zhang et al. 2009) Alternatively, another common object detection method , known as Optical Flow Analysis , may be utilized for vessel

Influence of aortic neck characteristics on successful aortic wall penetration of EndoAnchors in therapeutic use during endovascular aneurysm repair.

PubMed

Goudeketting, Seline R; van Noort, Kim; Ouriel, Kenneth; Jordan, William D; Panneton, Jean M; Slump, Cornelis H; de Vries, Jean-Paul P M

2018-04-21

This study sought to quantify EndoAnchor (Medtronic Vascular, Santa Rosa, Calif) penetration into the aortic wall in patients undergoing endovascular abdominal aortic aneurysm repair and to assess predictors of successful penetration and its relationship to postprocedural type IA endoleak. A subset of patients from the Aneurysm Treatment Using the Heli-FX Aortic Securement System Global Registry (ANCHOR) were included if they met the following criteria: the indication for EndoAnchor use was to treat a type IA endoleak, and postprocedure contrast-enhanced computed tomography (CT) scans of sufficient quality were available for core laboratory review. Patients undergoing implantation of cuffs or stents during the EndoAnchor implantation procedure were excluded. Baseline anatomic characteristics were recorded. The cohort was divided into patients with and without persistent type IA endoleaks at the first postoperative CT scan. Penetration of each EndoAnchor measured on this CT scan was defined as good penetration when the EndoAnchor penetrated ≥2 mm into the aortic wall, borderline penetration when EndoAnchor penetration was <2 mm or a gap remained between the endograft and aortic wall, or no penetration when the EndoAnchor did not penetrate into the aortic wall. Differences between the groups were analyzed with the Mann-Whitney U test or Fisher exact test. Multivariate analyses were performed to identify independent predictors of EndoAnchor penetration, and procedural success was defined by absence of type IA endoleak. Eighty-six patients of the primary (n = 61 [71%]) and revision (n = 25 [29%]) arms of the ANCHOR registry were included. There were 53 (62%) without and 33 (38%) with persistent type IA endoleaks on the first postprocedural CT scan. The median number of EndoAnchors with good penetration was significantly greater in the cohort without endoleaks, 4 (interquartile range, 3-5) vs 3 (interquartile range, 1.5-4), respectively (P = .002). A multivariate model for EndoAnchor penetration identified use of a Medtronic Endurant endograft as a factor associated with good penetration (P = .001), whereas poor penetration was associated with a larger aortic neck diameter 10 mm distal to the lowest renal artery (P < .001) and greater proximal neck calcium thickness (P = .004). EndoAnchor penetration was the only variable that attained significance (P < .001) in the multivariate model for successful treatment of a type IA endoleak. Adequate EndoAnchor penetration into the aortic wall is less likely when the aortic neck diameter is large or when the neck contains significant mural calcium. No penetration of the EndoAnchor was the only factor predictive of postprocedural type IA endoleak. This study stresses the importance of careful selection of patients based on preoperative assessment of the infrarenal neck on CT angiography and emphasizes careful deployment of EndoAnchors into the aortic wall to improve successful treatment of type IA endoleaks. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Cellular convection in the atmosphere of Venus

NASA Technical Reports Server (NTRS)

Baker, R. D., II; Schubert, Gerald

1992-01-01

Among the most intriguing feature of the atmosphere of Venus is the presence of cellular structures near and downwind of the subpolar point. It has been suggested that the structures are atmospheric convection cells, but their breadth and thinness would pose a severe challenge to the dynamics of convection. It is proposed here that strongly penetrative convection into the stable regions above and below the neutrally stable cloud layer coupled with penetrative convection from the surface increases the vertical dimensions of the cells, thereby helping to explain their large horizontal extent.

Commercial perspective in THz spectroscopy, sensing and imaging (Conference Presentation)

NASA Astrophysics Data System (ADS)

Bouyé, Clémentine; Taoudi, Sarah; Cochard, Jacques; d'Humières, Benoît

2017-02-01

For their ability to be transmitted by materials opaque in the visible and IR ranges (clothes, plastic, …), for being non-ionizing, for providing sub-mm resolution imaging, for the specific signatures of numerous materials, Terahertz waves - ranging from 200 GHz to 10 THz - have been raising the interest of industrials for about fifteen years. This study focuses on the penetration of THz technologies into the industrial applications driving the THz market growth at short and long term: Non Destructive testing (NDT), Defense and Security, Biomedical. For 15 years, Terahertz technologies have been continuously tested on a wide variety of applications. Thanks to these ongoing feasibility studies, manufacturers and end-users gained a deeper knowledge about the abilities and the limitations of the different Terahertz systems (Time-Domain spectroscopy, Frequency-Domain spectroscopy, Time-Domain reflectometry, etc). The demand from end-users is more qualified and is segmented as follows: 1. Detection of objects and defects on large areas 2. Thickness measurement on large areas 3. Chemical and Structural characterization of small objects and defects on small areas (2D) or volumes (3D) Each of these 3 functions leads to a specific family of THz systems with distinct requirements in terms of performance and cost: 1. Detection: cheap and compact imaging systems. 2. Thickness measurement: cost-effective and high speed systems. 3. Characterization: high resolution, high reliability and real-time sensing systems. This article will present the existing and incoming THz systems and components addressing each function. Terahertz technologies are currently finding their place on the market, outside research and scientific applications. The objective of this article is to identify the industrial applications where THz techniques will be adopted and to provide market growth perspectives.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schauder, C.

This subcontract report was completed under the auspices of the NREL/SCE High-Penetration Photovoltaic (PV) Integration Project, which is co-funded by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) and the California Solar Initiative (CSI) Research, Development, Demonstration, and Deployment (RD&D) program funded by the California Public Utility Commission (CPUC) and managed by Itron. This project is focused on modeling, quantifying, and mitigating the impacts of large utility-scale PV systems (generally 1-5 MW in size) that are interconnected to the distribution system. This report discusses the concerns utilities have when interconnecting large PV systems thatmore » interconnect using PV inverters (a specific application of frequency converters). Additionally, a number of capabilities of PV inverters are described that could be implemented to mitigate the distribution system-level impacts of high-penetration PV integration. Finally, the main issues that need to be addressed to ease the interconnection of large PV systems to the distribution system are presented.« less

Reconstructing the internal structure and long-term evolution of hazardous sinkholes combining trenching, electrical resistivity imaging (ERI) and ground penetrating radar (GPR)

NASA Astrophysics Data System (ADS)

Fabregat, Ivan; Gutiérrez, Francisco; Roqué, Carles; Comas, Xavier; Zarroca, Mario; Carbonel, Domingo; Guerrero, Jesús; Linares, Rogelio

2017-05-01

The approaches aimed at characterising specific damaging sinkholes have received limited attention compared with other ground instability phenomena (e.g. landslides). Moreover, the practicality of the trenching technique in combination with numerical dating and retro-deformation analysis for sinkhole site-investigations has been barely explored. This work illustrates the advantages of combining geomorphic mapping, electrical resistivity imaging (ERI), ground penetrating radar (GPR) and trenching for sinkhole characterisation and shows how the trenching technique contributes to fill significant gaps that neither geomorphic nor geophysical methods can address. Two large sinkholes (> 200 m long) related to the interstratal karstification of evaporites and generated by contrasting subsidence mechanisms (sagging, collapse) were investigated in the Fluvia Valley, NE Spain. Although GPR data may provide high resolution information on subsidence-related stratigraphic and structural features at shallow depth, the profiles acquired in the investigated sites with 100 MHz shielded and 40 MHz unshielded antennae provided limited insight into the internal geometry of the sinkholes due to reduced signal penetration related to the presence of conductive clayey material. The ERI sections satisfactorily imaged the general geometry of the sagging and collapse subsidence structures up to depths higher than 100 m and clearly captured the basal contact of the low-resistivity sinkhole fill in the sections with adequate layout and resolution. The trenches, despite their limited depth (ca. 5 m) allowed us to obtain valuable objective information on several key aspects of the subsidence phenomenon: (1) mechanisms (deformation style) and kinematics (progressive versus episodic); (2) limits of ground deformation; (3) temporal evolution (expansion versus contraction); (4) chronology and timing of most recent deformation phase; (5) rates of subsidence and sedimentation; and (6) the role played by subsidence in the development of lacustrine environments and the associated sedimentation patterns.

Comparative Response of Microchannel Plate and Channel Electron Multiplier Detectors to Penetrating Radiation in Space

DOE PAGES

Funsten, Herbert O.; Harper, Ronnie W.; Dors, Eric E.; ...

2015-10-02

Channel electron multiplier (CEM) and microchannel plate (MCP) detectors are routinely used in space instrumentation for measurement of space plasmas. Here, our goal is to understand the relative sensitivities of these detectors to penetrating radiation in space, which can generate background counts and shorten detector lifetime. We use 662 keV γ-rays as a proxy for penetrating radiation such as γ-rays, cosmic rays, and high-energy electrons and protons that are ubiquitous in the space environment. We find that MCP detectors are ~20 times more sensitive to 662 keV γ-rays than CEM detectors. This is attributed to the larger total area ofmore » multiplication channels in an MCP detector that is sensitive to electronic excitation and ionization resulting from the interaction of penetrating radiation with the detector material. In contrast to the CEM detector, whose quantum efficiency ε γ for 662 keVγ -rays is found to be 0.00175 and largely independent of detector bias, the quantum efficiency of the MCP detector is strongly dependent on the detector bias, with a power law index of 5.5. Lastly, background counts in MCP detectors from penetrating radiation can be reduced using MCP geometries with higher pitch and smaller channel diameter.« less

Hydration Effects on Skin Microstructure as Probed by High-Resolution Cryo-Scanning Electron Microscopy and Mechanistic Implications to Enhanced Transcutaneous Delivery of Biomacromolecules

PubMed Central

Tan, Grace; Xu, Peng; Lawson, Louise B.; He, Jibao; Freytag, Lucia C.; Clements, John D.; John, Vijay T.

2010-01-01

Although hydration is long known to improve the permeability of skin, penetration of macromolecules such as proteins is limited and the understanding of enhanced transport is based on empirical observations. This study uses high-resolution cryo-scanning electron microscopy to visualize microstructural changes in the stratum corneum (SC) and enable a mechanistic interpretation of biomacromolecule penetration through highly hydrated porcine skin. Swollen corneocytes, separation of lipid bilayers in the SC intercellular space to form cisternae, and networks of spherical particulates are observed in porcine skin tissue hydrated for a period of 4–10 h. This is explained through compaction of skin lipids when hydrated, a reversal in the conformational transition from unilamellar liposomes in lamellar granules to lamellae between keratinocytes when the SC skin barrier is initially established. Confocal microscopy studies show distinct enhancement in penetration of fluorescein isothiocyanate-bovine serum albumin (FITC-BSA) through skin hydrated for 4–10 h, and limited penetration of FITC-BSA once skin is restored to its natively hydrated structure when exposed to the environment for 2–3 h. These results demonstrate the effectiveness of a 4–10 h hydration period to enhance transcutaneous penetration of large biomacromolecules without permanently damaging the skin. PMID:19582754

Measurement of tritium penetration through concrete material covered by various paints coating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edao, Y.; Kawamura, Y.; Kurata, R.

The present study aims at obtaining fundamental data on tritium migration in porous materials, which include soaking effect, interaction between tritium and cement paste coated with paints and transient tritium sorption in porous cement. The amounts of tritium penetrated into or released from cement paste with epoxy and urethane paint coatings were measured. The tritium penetration amounts were increased with the HTO (tritiated water) exposure time. Time to achieve a saturated value of tritium sorption was more than 60 days for cement paste coated with epoxy paint and with urethane paint, while that for cement paste without any paint coatingmore » took 2 days to achieve it. The effect of tritium permeation reduction by the epoxy paint was higher than that of the urethane. Although their paint coatings were effective for reduction of tritium penetration through the cement paste which was exposed to HTO for a short period, it was found that the amount of tritium trapped in the paints became large for a long period. Tritium penetration rates were estimated by an analysis of one-dimensional diffusion in the axial direction of a thickness of a sample. Obtained data were helpful for evaluation of tritium contamination and decontamination. (authors)« less

Scalable Method to Produce Biodegradable Nanoparticles that Rapidly Penetrate Human Mucus

PubMed Central

Xu, Qingguo; Boylan, Nicholas J.; Cai, Shutian; Miao, Bolong; Patel, Himatkumar; Hanes, Justin

2013-01-01

Mucus typically traps and rapidly removes foreign particles from the airways, gastrointestinal tract, nasopharynx, female reproductive tract and the surface of the eye. Nanoparticles capable of rapid penetration through mucus can potentially avoid rapid clearance, and open significant opportunities for controlled drug delivery at mucosal surfaces. Here, we report an industrially scalable emulsification method to produce biodegradable mucus-penetrating particles (MPP). The emulsification of diblock copolymers of poly(lactic-co-glycolic acid) and polyethylene glycol (PLGA-PEG) using low molecular weight (MW) emulsifiers forms dense brush PEG coatings on nanoparticles that allow rapid nanoparticle penetration through fresh undiluted human mucus. In comparison, conventional high MW emulsifiers, such as polyvinyl alcohol (PVA), interrupts the PEG coating on nanoparticles, resulting in their immobilization in mucus owing to adhesive interactions with mucus mesh elements. PLGA-PEG nanoparticles with a wide range of PEG MW (1, 2, 5, and 10 kDa), prepared by the emulsification method using low MW emulsifiers, all rapidly penetrated mucus. A range of drugs, from hydrophobic small molecules to hydrohilic large biologics, can be efficiently loaded into biodegradable MPP using the method described. This readily scalable method should facilitate the production of MPP products for mucosal drug delivery, as well as potentially longer-circulating particles following intravenous administration. PMID:23751567

High speed ground penetrating radar for road pavement and bridge structural inspection and maintenance : final report.

DOT National Transportation Integrated Search

2016-06-30

The overarching objective of this research is the development of a systematic methodology of employing GPR, including instruments, subsequent data processing and interpretation that can be used regularly as part of a roadway pavement and bridge evalu...

Effective implementation of ground penetrating radar (GPR) for condition assessment and monitoring phase 2 : research summary.

DOT National Transportation Integrated Search

2016-10-01

This University of Maryland (UMD) project, in cooperation with Starodub Inc, : had the following objectives: : 1) Provide data analysis support for 40 bridge decks; : 2) Develop the analysis pipeline for producing structural reports according to the ...

Motion/visual cueing requirements for vortex encounters during simulated transport visual approach and landing

NASA Technical Reports Server (NTRS)

Parrish, R. V.; Bowles, R. L.

1983-01-01

This paper addresses the issues of motion/visual cueing fidelity requirements for vortex encounters during simulated transport visual approaches and landings. Four simulator configurations were utilized to provide objective performance measures during simulated vortex penetrations, and subjective comments from pilots were collected. The configurations used were as follows: fixed base with visual degradation (delay), fixed base with no visual degradation, moving base with visual degradation (delay), and moving base with no visual degradation. The statistical comparisons of the objective measures and the subjective pilot opinions indicated that although both minimum visual delay and motion cueing are recommended for the vortex penetration task, the visual-scene delay characteristics were not as significant a fidelity factor as was the presence of motion cues. However, this indication was applicable to a restricted task, and to transport aircraft. Although they were statistically significant, the effects of visual delay and motion cueing on the touchdown-related measures were considered to be of no practical consequence.

Application of advanced speech technology in manned penetration bombers

NASA Astrophysics Data System (ADS)

North, R.; Lea, W.

1982-03-01

This report documents research on the potential use of speech technology in a manned penetration bomber aircraft (B-52/G and H). The objectives of the project were to analyze the pilot/copilot crewstation tasks over a three-hour-and forty-minute mission and determine the tasks that would benefit the most from conversion to speech recognition/generation, determine the technological feasibility of each of the identified tasks, and prioritize these tasks based on these criteria. Secondary objectives of the program were to enunciate research strategies in the application of speech technologies in airborne environments, and develop guidelines for briefing user commands on the potential of using speech technologies in the cockpit. The results of this study indicated that for the B-52 crewmember, speech recognition would be most beneficial for retrieving chart and procedural data that is contained in the flight manuals. Technological feasibility of these tasks indicated that the checklist and procedural retrieval tasks would be highly feasible for a speech recognition system.

Numerical simulation of the effect of regular and sub-caliber projectiles on military bunkers

NASA Astrophysics Data System (ADS)

Jiricek, Pavel; Foglar, Marek

2015-09-01

One of the most demanding topics in blast and impact engineering is the modelling of projectile impact. To introduce this topic, a set of numerical simulations was undertaken. The simulations study the impact of regular and sub-calibre projectile on Czech pre-WW2 military bunkers. The penetrations of the military objects are well documented and can be used for comparison. The numerical model composes of a part from a wall of a military object. The concrete block is subjected to an impact of a regular and sub-calibre projectile. The model is divided into layers to simplify the evaluation of the results. The simulations are processed within ANSYS AUTODYN software. A nonlinear material model of with damage and incorporated strain-rate effect was used. The results of the numerical simulations are evaluated in means of the damage of the concrete block. Progress of the damage is described versus time. The numerical simulation provides good agreement with the documented penetrations.

Design of energy storage system to improve inertial response for large scale PV generation

DOE PAGES

Wang, Xiaoyu; Yue, Meng

2016-07-01

With high-penetration levels of renewable generating sources being integrated into the existing electric power grid, conventional generators are being replaced and grid inertial response is deteriorating. This technical challenge is more severe with photovoltaic (PV) generation than with wind generation because PV generation systems cannot provide inertial response unless special countermeasures are adopted. To enhance the inertial response, this paper proposes to use battery energy storage systems (BESS) as the remediation approach to accommodate the degrading inertial response when high penetrations of PV generation are integrated into the existing power grid. A sample power system was adopted and simulated usingmore » PSS/E software. Here, impacts of different penetration levels of PV generation on the system inertial response were investigated and then BESS was incorporated to improve the frequency dynamics.« less

Theoretic criteria for antibody penetration into solid tumors and micrometastases.

PubMed

Thurber, Greg M; Zajic, Stefan C; Wittrup, K Dane

2007-06-01

Targeting tumors with antibody-based therapeutics is a complex task presenting multiple kinetic barriers. Antibody internalization and clearance inhibit uptake both in solid tumors, limited by tumor vascular permeability, and in micrometastases, limited by diffusion. A modeling exercise is used to introduce 2 simple criteria that must be less than unity for saturation of both tumors and micrometastases. The clearance modulus and the Thiele modulus are ratios of the plasma clearance rate and antibody catabolism, respectively, to the tumor tissue penetration rate. Even low rates of antigen internalization from constitutive membrane turnover can significantly retard antibody penetration. Rapid clearance of single-chain variable fragments also hinders uptake, often more than counterbalancing their more rapid extravasation and diffusion. The model illustrates that with the large resistance from the tumor capillary, antibodies may be more suitable for targeting micrometastases than vascularized tumors.

Outlook and application analysis of energy storage in power system with high renewable energy penetration

NASA Astrophysics Data System (ADS)

Feng, Junshu; Zhang, Fuqiang

2018-02-01

To realize low-emission and low-carbon energy production and consumption, large-scale development and utilization of renewable energy has been put into practice in China. And it has been recognized that power system of future high renewable energy shares can operate more reliably with the participation of energy storage. Considering the significant role of storage playing in the future power system, this paper focuses on the application of energy storage with high renewable energy penetration. Firstly, two application modes are given, including demand side application mode and centralized renewable energy farm application mode. Afterwards, a high renewable energy penetration scenario of northwest region in China is designed, and its production simulation with application of energy storage in 2050 has been calculated and analysed. Finally, a development path and outlook of energy storage is given.

Hydrodynamical simulations of strong tides in astrophysical systems

NASA Astrophysics Data System (ADS)

Guillochon, James

2013-07-01

At the simplest level, gravitational sources are considered to be point-like and in solitude, with a radial force that falls off as r -2. In reality, all astrophysical objects aside from black holes are extended in space, and can be deformed by the tidal forces arising from the proximity of companion objects with large average densities. When these forces are weak, the response of an object to a tide can be through a decomposition into basis functions, but this approach fails when the tide is strong enough to deform an object by a distance equal to its own size. Under these circumstances, a hydrodynamical representation of the object is required to understand the true tidal response. In this thesis, we present a number of examples of physical systems in which tides dominate the dynamics. First, we consider the case of a star that encounters a supermassive black hole (SMBH) in a deeply penetrating encounter, resulting in a dramatic compression that produces shocks that would be observable in the X-ray. Second, we present the results of hydrodynamical simulations that demonstrate a new mechanism for igniting Type Ia supernovae from binary systems composed of two white dwarfs undergoing Roche-lobe overflow. Third, we investigate the survival prospects of giant planets that have been scattered into highly eccentricity orbits and are exposed to a strong tide applied by their parent star. Fourth, we systematically map the fallback rate resulting from the tidal disruptions of stars by SMBHs. Finally, we use what we have learned about the feeding rate to model determine the highest-likelihood model for an observed prototypical tidal disruption event.

Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance.

PubMed

Hiddink, Jan Geert; Jennings, Simon; Sciberras, Marija; Szostek, Claire L; Hughes, Kathryn M; Ellis, Nick; Rijnsdorp, Adriaan D; McConnaughey, Robert A; Mazor, Tessa; Hilborn, Ray; Collie, Jeremy S; Pitcher, C Roland; Amoroso, Ricardo O; Parma, Ana M; Suuronen, Petri; Kaiser, Michel J

2017-08-01

Bottom trawling is the most widespread human activity affecting seabed habitats. Here, we collate all available data for experimental and comparative studies of trawling impacts on whole communities of seabed macroinvertebrates on sedimentary habitats and develop widely applicable methods to estimate depletion and recovery rates of biota after trawling. Depletion of biota and trawl penetration into the seabed are highly correlated. Otter trawls caused the least depletion, removing 6% of biota per pass and penetrating the seabed on average down to 2.4 cm, whereas hydraulic dredges caused the most depletion, removing 41% of biota and penetrating the seabed on average 16.1 cm. Median recovery times posttrawling (from 50 to 95% of unimpacted biomass) ranged between 1.9 and 6.4 y. By accounting for the effects of penetration depth, environmental variation, and uncertainty, the models explained much of the variability of depletion and recovery estimates from single studies. Coupled with large-scale, high-resolution maps of trawling frequency and habitat, our estimates of depletion and recovery rates enable the assessment of trawling impacts on unprecedented spatial scales.

Abscisic acid negatively regulates post-penetration resistance of Arabidopsis to the biotrophic powdery mildew fungus.

PubMed

Xiao, Xiang; Cheng, Xi; Yin, Kangquan; Li, Huali; Qiu, Jin-Long

2017-08-01

Pytohormone abscisic acid (ABA) plays important roles in defense responses. Nonetheless, how ABA regulates plant resistance to biotrophic fungi remains largely unknown. Arabidopsis ABA-deficient mutants, aba2-1 and aba3-1, displayed enhanced resistance to the biotrophic powdery mildew fungus Golovinomyces cichoracearum. Moreover, exogenously administered ABA increased the susceptibility of Arabidopsis to G. cichoracearum. Arabidopsis ABA perception components mutants, abi1-1 and abi2-1, also displayed similar phenotypes to ABA-deficient mutants in resistance to G. cichoracearum. However, the resistance to G. cichoracearum is not changed in downstream ABA signaling transduction mutants, abi3-1, abi4-1, and abi5-1. Microscopic examination revealed that hyphal growth and conidiophore production of G. cichoracearum were compromised in the ABA deficient mutants, even though pre-penetration and penetration growth of the fungus were not affected. In addition, salicylic acid (SA) and MPK3 are found to be involved in ABA-regulated resistance to G. cichoracearum. Our work demonstrates that ABA negatively regulates post-penetration resistance of Arabidopsis to powdery mildew fungus G. cichoracearum, probably through antagonizing the function of SA.

Perception and Cognition Are Largely Independent, but Still Affect Each Other in Systematic Ways: Arguments from Evolution and the Consciousness-Attention Dissociation

PubMed Central

Montemayor, Carlos; Haladjian, Harry H.

2017-01-01

The main thesis of this paper is that two prevailing theories about cognitive penetration are too extreme, namely, the view that cognitive penetration is pervasive and the view that there is a sharp and fundamental distinction between cognition and perception, which precludes any type of cognitive penetration. These opposite views have clear merits and empirical support. To eliminate this puzzling situation, we present an alternative theoretical approach that incorporates the merits of these views into a broader and more nuanced explanatory framework. A key argument we present in favor of this framework concerns the evolution of intentionality and perceptual capacities. An implication of this argument is that cases of cognitive penetration must have evolved more recently and that this is compatible with the cognitive impenetrability of early perceptual stages of processing information. A theoretical approach that explains why this should be the case is the consciousness and attention dissociation framework. The paper discusses why concepts, particularly issues concerning concept acquisition, play an important role in the interaction between perception and cognition. PMID:28174551

Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance

PubMed Central

Hiddink, Jan Geert; Jennings, Simon; Sciberras, Marija; Szostek, Claire L.; Hughes, Kathryn M.; Ellis, Nick; Rijnsdorp, Adriaan D.; McConnaughey, Robert A.; Mazor, Tessa; Hilborn, Ray; Collie, Jeremy S.; Pitcher, C. Roland; Amoroso, Ricardo O.; Parma, Ana M.; Suuronen, Petri; Kaiser, Michel J.

2017-01-01

Bottom trawling is the most widespread human activity affecting seabed habitats. Here, we collate all available data for experimental and comparative studies of trawling impacts on whole communities of seabed macroinvertebrates on sedimentary habitats and develop widely applicable methods to estimate depletion and recovery rates of biota after trawling. Depletion of biota and trawl penetration into the seabed are highly correlated. Otter trawls caused the least depletion, removing 6% of biota per pass and penetrating the seabed on average down to 2.4 cm, whereas hydraulic dredges caused the most depletion, removing 41% of biota and penetrating the seabed on average 16.1 cm. Median recovery times posttrawling (from 50 to 95% of unimpacted biomass) ranged between 1.9 and 6.4 y. By accounting for the effects of penetration depth, environmental variation, and uncertainty, the models explained much of the variability of depletion and recovery estimates from single studies. Coupled with large-scale, high-resolution maps of trawling frequency and habitat, our estimates of depletion and recovery rates enable the assessment of trawling impacts on unprecedented spatial scales. PMID:28716926

Multi-mounted X-ray cone-beam computed tomography

NASA Astrophysics Data System (ADS)

Fu, Jian; Wang, Jingzheng; Guo, Wei; Peng, Peng

2018-04-01

As a powerful nondestructive inspection technique, X-ray computed tomography (X-CT) has been widely applied to clinical diagnosis, industrial production and cutting-edge research. Imaging efficiency is currently one of the major obstacles for the applications of X-CT. In this paper, a multi-mounted three dimensional cone-beam X-CT (MM-CBCT) method is reported. It consists of a novel multi-mounted cone-beam scanning geometry and the corresponding three dimensional statistical iterative reconstruction algorithm. The scanning geometry is the most iconic design and significantly different from the current CBCT systems. Permitting the cone-beam scanning of multiple objects simultaneously, the proposed approach has the potential to achieve an imaging efficiency orders of magnitude greater than the conventional methods. Although multiple objects can be also bundled together and scanned simultaneously by the conventional CBCT methods, it will lead to the increased penetration thickness and signal crosstalk. In contrast, MM-CBCT avoids substantially these problems. This work comprises a numerical study of the method and its experimental verification using a dataset measured with a developed MM-CBCT prototype system. This technique will provide a possible solution for the CT inspection in a large scale.

Particle Beam Radiography

NASA Astrophysics Data System (ADS)

Peach, Ken; Ekdahl, Carl

2014-02-01

Particle beam radiography, which uses a variety of particle probes (neutrons, protons, electrons, gammas and potentially other particles) to study the structure of materials and objects noninvasively, is reviewed, largely from an accelerator perspective, although the use of cosmic rays (mainly muons but potentially also high-energy neutrinos) is briefly reviewed. Tomography is a form of radiography which uses multiple views to reconstruct a three-dimensional density map of an object. There is a very wide range of applications of radiography and tomography, from medicine to engineering and security, and advances in instrumentation, specifically the development of electronic detectors, allow rapid analysis of the resultant radiographs. Flash radiography is a diagnostic technique for large high-explosive-driven hydrodynamic experiments that is used at many laboratories. The bremsstrahlung radiation pulse from an intense relativistic electron beam incident onto a high-Z target is the source of these radiographs. The challenge is to provide radiation sources intense enough to penetrate hundreds of g/cm2 of material, in pulses short enough to stop the motion of high-speed hydrodynamic shocks, and with source spots small enough to resolve fine details. The challenge has been met with a wide variety of accelerator technologies, including pulsed-power-driven diodes, air-core pulsed betatrons and high-current linear induction accelerators. Accelerator technology has also evolved to accommodate the experimenters' continuing quest for multiple images in time and space. Linear induction accelerators have had a major role in these advances, especially in providing multiple-time radiographs of the largest hydrodynamic experiments.

Pre-heating mitigates composite degradation

PubMed Central

da SILVA, Jessika Calixto; Rogério Vieira, REGES; REGE, Inara Carneiro Costa; CRUZ, Carlos Alberto dos Santos; VAZ, Luís Geraldo; ESTRELA, Carlos; de CASTRO, Fabrício Luscino Alves

2015-01-01

ABSTRACT Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions: 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey’s tests (α=5%). Results Radiopacity levels were as follows: Durafill VSZ-350>Z-250 (p<0.05). After storage in water/NaOH, pre-heated specimens presented higher radiopacity values than non-pre-heated specimens (p<0.05). There was a lower penetration of silver in pre-heated specimens (p<0.05). Conclusions Pre-heating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth. PMID:26814459

Design and intestinal mucus penetration mechanism of core-shell nanocomplex.

PubMed

Zhang, Xin; Cheng, Hongbo; Dong, Wei; Zhang, Meixia; Liu, Qiaoyu; Wang, Xiuhua; Guan, Jian; Wu, Haiyang; Mao, Shirui

2018-02-28

The objective of this study was to design intestinal mucus-penetrating core-shell nanocomplex by functionally mimicking the surface of virus, which can be used as the carrier for peroral delivery of macromolecules, and further understand the influence of nanocomplex surface properties on the mucosal permeation capacity. Taking insulin as a model drug, the core was formed by the self-assembly among positively charged chitosan, insulin and negatively charged sodium tripolyphosphate, different types of alginates were used as the shell forming material. The nanocomplex was characterized by dynamic light scattering (DLS), atomic force microscopy (AFM) and FTIR. Nanocomplex movement in mucus was recorded using multiple particle tracking (MPT) method. Permeation and uptake of different nanocomplex were studied in rat intestine. It was demonstrated that alginate coating layer was successfully formed on the core and the core-shell nanocomplex showed a good physical stability and improved enzymatic degradation protection. The mucus penetration and MPT study showed that the mucus penetration capacity of the nanocomplex was surface charge and coating polymer structure dependent, nanocomplex with negative alginate coating had 1.6-2.5 times higher mucus penetration ability than that of positively charged chitosan-insulin nanocomplex. Moreover, the mucus penetration ability of the core-shell nanocomplex was alginate structure dependent, whereas alginate with lower G content and lower molecular weight showed the best permeation enhancing ability. The improvement of intestine permeation and intestinal villi uptake of the core-shell nanocomplex were further confirmed in rat intestine and multiple uptake mechanisms were involved in the transport process. In conclusion, core-shell nanocomplex composed of oppositely charged materials could provide a strategy to overcome the mucus barrier and enhance the mucosal permeability. Copyright © 2018 Elsevier B.V. All rights reserved.

Modelling the effect of mixture components on permeation through skin.

PubMed

Ghafourian, T; Samaras, E G; Brooks, J D; Riviere, J E

2010-10-15

A vehicle influences the concentration of penetrant within the membrane, affecting its diffusivity in the skin and rate of transport. Despite the huge amount of effort made for the understanding and modelling of the skin absorption of chemicals, a reliable estimation of the skin penetration potential from formulations remains a challenging objective. In this investigation, quantitative structure-activity relationship (QSAR) was employed to relate the skin permeation of compounds to the chemical properties of the mixture ingredients and the molecular structures of the penetrants. The skin permeability dataset consisted of permeability coefficients of 12 different penetrants each blended in 24 different solvent mixtures measured from finite-dose diffusion cell studies using porcine skin. Stepwise regression analysis resulted in a QSAR employing two penetrant descriptors and one solvent property. The penetrant descriptors were octanol/water partition coefficient, logP and the ninth order path molecular connectivity index, and the solvent property was the difference between boiling and melting points. The negative relationship between skin permeability coefficient and logP was attributed to the fact that most of the drugs in this particular dataset are extremely lipophilic in comparison with the compounds in the common skin permeability datasets used in QSAR. The findings show that compounds formulated in vehicles with small boiling and melting point gaps will be expected to have higher permeation through skin. The QSAR was validated internally, using a leave-many-out procedure, giving a mean absolute error of 0.396. The chemical space of the dataset was compared with that of the known skin permeability datasets and gaps were identified for future skin permeability measurements. Copyright 2010 Elsevier B.V. All rights reserved.

Filter penetration and breathing resistance evaluation of respirators and dust masks.

PubMed

Ramirez, Joel; O'Shaughnessy, Patrick

2017-02-01

The primary objective of this study was to compare the filter performance of a representative selection of uncertified dust masks relative to the filter performance of a set of NIOSH-approved N95 filtering face-piece respirators (FFRs). Five different models of commercially available dust masks were selected for this study. Filter penetration of new dust masks was evaluated against a sodium chloride aerosol. Breathing resistance (BR) of new dust masks and FFRs was then measured for 120 min while challenging the dust masks and FFRs with Arizona road dust (ARD) at 25°C and 30% relative humidity. Results demonstrated that a wide range of maximum filter penetration was observed among the dust masks tested in this study (3-75% at the most penetrating particle size (p < 0.001). The breathing resistances of the unused FFRs and dust masks did not vary greatly (8-13 mm H 2 O) but were significantly different (p < 0.001). After dust loading there was a significant difference between the BR caused by the ARD dust layer on each FFR and dust mask. Microscopic analysis of the external layer of each dust mask and FFR suggests that different collection media in the external layer influences the development of the dust layer and therefore affects the increase in BR differently between the tested models. Two of the dust masks had penetration values < 5% and quality factors (0.26 and 0.33) comparable to those obtained for the two FFRs (0.23 and 0.31). However, the remaining three dust masks, those with penetration > 15%, had quality factors ranging between 0.04-0.15 primarily because their initial BR remained relatively high. These results indicate that some dust masks analysed during this research did not have an expected very low BR to compensate for their high penetration.

Assessment of waterfront location in hardened concrete by GPR within COST Action TU1208

NASA Astrophysics Data System (ADS)

Rodríguez-Abad, Isabel; Klysz, Gilles; Balayssac, Jean Paul; Pajewski, Lara

2016-04-01

This work focuses on the analysis of the capability of Ground-Penetrating radar (GPR) technique for evaluating how the water penetrates into concrete samples by means of the assessment of the waterfront advance. Research activities have been carried out during a Short-Term Scientific Missions (STSMs) funded by the COST (European Cooperation in Science and Technology) Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar" in November 2015. The evaluation of water penetrability is crucial in most building materials, such us concrete, since, water and aggressive chemical agents dissolved therein contribute to the deterioration of the material. A number of techniques have been developed to measure their advance in concrete. Although the most common method for measuring water content is the gravimetric method by observing the change in mass, this method has a large number of disadvantages. In this context, non-destructive techniques as GPR play an interesting role. In particular, the application of GPR in the building materials area is providing very promising and interesting results regarding the building materials characterization and especially concrete deterioration evaluation [1-3]. In addition, recent experimental studies highlight the strong relation between wave propagation parameters (velocity and energy level) and water content advance [4-5]. Water content has a decisive influence on dielectric properties and those might be assessed by the study of the wave properties that are derived by using GPR. Therefore, the waterfront advance will result in a change on wave parameters. In line with this, this research is focused on the development of specific processing algorithms necessary to understand how the water penetrates and how the wave parameters will be affected regarding the location of the antenna in reference to the water absorption direction. For this purpose, concrete samples were manufactured, which after curing (90 days) and oven drying were immersed into water for a certain time. Then, GPR measurements, with a 2 GHz central frequency antenna, were performed at specific time intervals, placing the antenna on the same side of the concrete samples that was immersed into water. After conducting GPR measurements, concrete samples were broken in two pieces to perform the visual analysis of the waterfront advance. After processing the GPR records velocity increments ware calculated and analyzed. Very accurate adjustments were found between the velocity increments and the waterfront depth, regardless the wave peaks of the direct and reflected wave used to calculate velocity increments. These results are of quite importance, because even if we are not able to locate the waterfront reflection or if it is overlapped with the direct wave signal, we might predict the waterfront position with high reliability. Acknowledgement The Authors are grateful to COST - European Cooperation in Science and Technology (www.cost.eu) for funding the Action TU1208 "Civil engineering applications of Ground Penetrating Radar" (www.GPRadar.eu). References 1. W. Lai, S. Kou, W. Tsang, C. Poon, "Characterization of concrete properties from dielectric properties using ground penetrating radar," Cement and Concrete Research, Vol. 39, pp. 687-695, 2009. 2. W. Chen, P. Shen, Z. Shui, "Determination of water content in fresh concrete mix based on relative dielectric constant measurement," Construction and Building Materials, Vol. 34, pp. 306-312, 2012. 3. S. Senin, R. Hamid, "Ground penetrating radar wave attenuation models for estimation of moisture and chloride content in concrete slab," Construction and Building Materials, Vol. 106, pp. 659-669, 2016. 4.I. Rodríguez-Abad , R. Martínez-Sala, J. Mené Aparicio, G. Klysz, "Water penetrability in hardened concrete by GPR," Proceedings of the 15th International Conference on Ground Penetrating Radar, Brussels, Belgium, 2014. 5.I. Rodríguez-Abad, G. Klysz, R. Martínez-Sala, J.P. Balayssac, J. Mené Aparicio, "Waterfront depth analysis in hardened concrete by means of the nondestructive Ground-penetrating radar technique," IEEE Journal of Selected Topics In Applied Earth Observations and Remote Sensing. Digital Object Identifier 10.1109/JSTARS.2015.2449737, 2015.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Checco, A.; Hofmann, T.; DiMasi, E.

The details of air nanobubble trapping at the interface between water and a nanostructured hydrophobic silicon surface are investigated using X-ray scattering and contact angle measurements. Large-area silicon surfaces containing hexagonally packed, 20 nm wide hydrophobic cavities provide ideal model surfaces for studying the morphology of air nanobubbles trapped inside cavities and its dependence on the cavity depth. Transmission small-angle X-ray scattering measurements show stable trapping of air inside the cavities with a partial water penetration of 5-10 nm into the pores, independent of their large depth variation. This behavior is explained by consideration of capillary effects and the cavitymore » geometry. For parabolic cavities, the liquid can reach a thermodynamically stable configuration - a nearly planar nanobubble meniscus - by partially penetrating into the pores. This microscopic information correlates very well with the macroscopic surface wetting behavior.« less

Development of transferrin targeted NCL-240 micelles and their evaluation using in-vitro 3D cancer cell culture (spheroid) models

NASA Astrophysics Data System (ADS)

Nagelli, Srikar Goud

The main objective of this project was to develop targeted micellar delivery systems of a novel cytotoxic drug (NCL-240; a second generation DM-PIT-1 analog) and to evaluate their efficacy using optimized 3D cell culture spheroid models. Spheroids were optimized for several cancer cell lines using a range of techniques such as non-adhesive liquid overlay method, hanging drop method, and co-culturing. Transferrin (Tf)-conjugated NCL-240 micelles were prepared with varying Tf amounts and their cytotoxicities were evaluated using the optimized spheroid models. The uptake and penetration of the formulations were also studied using confocal microscopy. The results indicated that the concentration of NCL-240 micelles required to achieve the same cytotoxicity was relatively higher in spheroids compared to the monolayers. Also, In NCI-ADR-RES, Tf-targeted NCL-240 micelles were shown to have a significant increase in cytotoxicity compared to untargeted NCL-240 micelles. Even the penetration and uptake studies indicated that targeting improves the uptake and penetration of formulations. However, in U87-MG spheroids, there was a significant difference in cell viability among micelles compared to free drug but no significant benefit due to targeting was observed. The same formulations penetrated lesser in U87-MG spheroids compared to NCI-ADR-RES spheroids. This study thereby emphasizes the importance of drug screening in spheroid models as the penetration dynamics are varying from cell line to cell line because of the 3D structure.

Estimation of the optimal timing of fertilization for embryo development of in vitro-matured bovine oocytes based on the times of nuclear maturation and sperm penetration.

PubMed

Koyama, Keisuke; Kang, Sung-Sik; Huang, Weiping; Yanagawa, Yojiro; Takahashi, Yoshiyuki; Nagano, Masashi

2014-05-01

The objective of this research was to estimate the optimal timing for fertilization to achieve proper embryonic development of in vitro-matured bovine oocytes. First, cumulus-oocyte complexes were subjected to in vitro maturation (IVM) for 14-22 hr. The timing when 50% of oocytes reached metaphase II stage was estimated to be 17.5 hr after IVM start. Next, using oocytes subjected to IVM for 12-30 hr, sperm penetration was examined after 4-18 hr of in vitro fertilization (IVF). A significant negative correlation between IVM duration and the timing when 50% of oocytes were penetrated by sperm after IVF start was observed (P<0.01). Finally, oocytes subjected to 12-30 hr of IVM were inseminated and cultured for 6 days to examine embryonic development. In the group with 22 hr of IVM, the percentages of cleaved embryos and blastocysts were the highest values in all groups. According to the regression equation describing the time from nuclear maturation to sperm penetration (x) and the percentage of blastocysts (y) (y=7.23x - 0.297x(2), P<0.01), the blastocyst rate peaked when sperm penetration occurred at 12.2 hr after achieving nuclear maturation. In conclusion, under the present IVM/IVF conditions, it was estimated that oocytes acquired their highest developmental competence at about 30 hr after IVM start, and thus, the optimal IVM duration was calculated to be about 21 hr.

The Influence of Physical Body Traits and Masculinity on Anal Sex Roles in Gay and Bisexual Men

PubMed Central

Moskowitz, David A.; Hart, Trevor A.

2016-01-01

Sociological, psychological, and public health studies document that many gay and bisexual men may self-label by their anal penetrative role (i.e., bottom or exclusively receptive; top or exclusively insertive; or versatile, both receptive and insertive during anal intercourse). Yet, what orients men to think of themselves as tops, bottoms or versatiles is poorly understood. We surveyed 429 men engaging in same-sex anal intercourse to investigate the degree to which anal penetrative self-identity was concordant with actual penetrative behavior. Additionally, the roles of masculinity and physical body traits (e.g., penis size, muscularity, height, hairiness, and weight) were tested as correlates of anal penetrative identity and identity-behavior concordance. Tops and bottoms showed a high degree of concordance between identity and enacted behavior; however, only half of versatiles reported concordant identity and behavior (i.e., wanting to be versatile and actually reporting versatile behavior). Generally, tops reported larger penises than bottoms. They also reported being comparatively more masculine than bottoms. Versatiles fell somewhat between the tops and bottoms on these traits. Of the six independent variables, penis size and masculinity were the only two factors to influence concordance or discordance between identity and penetrative behavior. Our study suggests that the correlates of gay men’s sexual self-labels may depend on objective traits in addition to the subjective pleasure associated with receptive or insertive anal intercourse. PMID:21465269

Penetrator Coring Apparatus for Cometary Surfaces

NASA Technical Reports Server (NTRS)

Braun, David F.; Heinrich, Michael; Ai, Huirong Anita; Ahrens, Thomas J.

2004-01-01

Touch and go impact coring is an attractive technique for sampling cometary nuclei and asteroidal surface on account of the uncertain strength properties and low surface gravities of these objects. Initial coring experiments in low temperature (approx. 153K polycrystalline ice) and porous rock demonstrate that simultaneous with impact coring, measurements of both the penetration strength and constraints on the frictional properties of surface materials can be obtained upon core penetration and core sample extraction. The method of sampling an asteroid, to be deployed, on the now launched MUSES-C mission, employs a small gun device that fires into the asteroid and the resulted impact ejecta is collected for return to Earth. This technique is well suited for initial sampling in a very low gravity environment and deployment depends little on asteroid surface mechanical properties. Since both asteroids and comets are believed to have altered surface properties a simple sampling apparatus that preserves stratigraphic information, such as impact coring is an attractive alternate to impact ejecta collection.

Accelerated dry curing of hams.

PubMed

Marriott, N G; Kelly, R F; Shaffer, C K; Graham, P P; Boling, J W

1985-01-01

Uncured pork legs from the right side of 18 carcasses were treated with a Ross Tenderizer and the left side were controls. All 36 samples were dry-cured for 40, 56 or 70 days and evaluated for appearance traits, cure penetration characteristics, microbial load, Kramer Shear force and taste attributes. The tenderization treatment had no effect (P > 0·05) on visual color or cure penetration rate, weight loss before curing, percentage moisture, nitrate level, nitrite level, total plate count, anaerobic counts, psychrotrophic counts, objective and subjective tenderness measurements or juiciness. However, the higher values of salt suggested a possible acceleration of the dry cure penetration process among the tenderized samples. Cure time had no effect (P > 0·05) on percentage moisture, percentage salt, nitrate content, nitrite content, shear force and juiciness. Results suggest a limited effect of the mechanical tenderization process on certain traits related to dry curing and that total process time should be at least 70 days if color stability during cooking is desired. Copyright © 1985. Published by Elsevier Ltd.

Coded Excitation Plane Wave Imaging for Shear Wave Motion Detection

PubMed Central

Song, Pengfei; Urban, Matthew W.; Manduca, Armando; Greenleaf, James F.; Chen, Shigao

2015-01-01

Plane wave imaging has greatly advanced the field of shear wave elastography thanks to its ultrafast imaging frame rate and the large field-of-view (FOV). However, plane wave imaging also has decreased penetration due to lack of transmit focusing, which makes it challenging to use plane waves for shear wave detection in deep tissues and in obese patients. This study investigated the feasibility of implementing coded excitation in plane wave imaging for shear wave detection, with the hypothesis that coded ultrasound signals can provide superior detection penetration and shear wave signal-to-noise-ratio (SNR) compared to conventional ultrasound signals. Both phase encoding (Barker code) and frequency encoding (chirp code) methods were studied. A first phantom experiment showed an approximate penetration gain of 2-4 cm for the coded pulses. Two subsequent phantom studies showed that all coded pulses outperformed the conventional short imaging pulse by providing superior sensitivity to small motion and robustness to weak ultrasound signals. Finally, an in vivo liver case study on an obese subject (Body Mass Index = 40) demonstrated the feasibility of using the proposed method for in vivo applications, and showed that all coded pulses could provide higher SNR shear wave signals than the conventional short pulse. These findings indicate that by using coded excitation shear wave detection, one can benefit from the ultrafast imaging frame rate and large FOV provided by plane wave imaging while preserving good penetration and shear wave signal quality, which is essential for obtaining robust shear elasticity measurements of tissue. PMID:26168181

Opportunities and Problems in Marketing Programs.

ERIC Educational Resources Information Center

Coe, Barbara J.; Welch, Joe

1988-01-01

A description and discussion of a university market penetration plan looks at problems and opportunities related to market selection, establishment of performance objectives, timing, use of human resources, developing a promotional plan and activities, doing a market survey, garnering alumni support, using the media, and using college-community…

High-Frequency Sound Interaction with Ocean Sediments and with Objects in the Vicinity of the Water/Sediment Interface and Mid-Frequency Shallow Water Propagation and Scattering

DTIC Science & Technology

2007-09-30

combined with measured sediment properties, to test the validity of sediment acoustic models , and in particular the poroelastic (Biot) model . Addressing...TERM GOALS 1. Development of accurate models for acoustic scattering from, penetration into, and propagation within shallow water ocean sediments...2. Development of reliable methods for modeling acoustic detection of buried objects at subcritical grazing angles. 3. Improving our

Ultrasonic Assessment of Impact-Induced Damage and Microcracking in Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Gyekanyesi, John (Technical Monitor); Liaw, Benjamin; Villars, Esther; Delmont, Frantz

2003-01-01

The main objective of this NASA Faculty Awards for Research (FAR) project is to conduct ultrasonic assessment of impact-induced damage and microcracking in fiber-metal laminated (FML) composites at various temperatures. It is believed that the proposed study of impact damage assessment on FML composites will benefit several NASA's missions and current interests, such as ballistic impact testing of composite fan containment and high strain rate deformation modeling of polymer matrix composites. Impact-induced damage mechanisms in GLARE and ARALL fiber-metal laminates subject to instrumented drop-weight impacts at various temperatures were studied. GLARE and ARALL are hybrid composites made of alternating layers of aluminum and glass- (for GLARE) and aramid- (for ARALL) fiber reinforced epoxy. Damage in pure aluminum panels impacted by foreign objects was mainly characterized by large plastic deformation surrounding a deep penetration dent. On the other hand, plastic deformation in fiber-metal laminates was often not as severe although the penetration dent was still produced. The more stiff fiber-reinforced epoxy layers provided better bending rigidity; thus, enhancing impact damage tolerance. Severe cracking, however, occurred due to the use of these more brittle fiber-reinforced epoxy layers. Fracture patterns, e.g., crack length and delamination size, were greatly affected by the lay-up configuration rather than by the number of layers, which implies that thickness effect was not significant for the panels tested in this study. Immersion ultrasound techniques were then used to assess damages generated by instrumented drop-weight impacts onto these fiber-metal laminate panels as well as 2024-T3 aluminum/cast acrylic sandwich plates adhered by epoxy. Depending on several parameters, such as impact velocity, mass, temperature, laminate configuration, sandwich construction, etc., various types of impact damage were observed, including plastic deformation, radiating cracks emanating from the impact site, ring cracks surrounding the impact site, partial and full delamination, and combinations of these damages.

Ultrasonic Assessment of Impact-Induced Damage and Microcracking in Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Liaw, Benjamin; Villars, Esther; Delmont, Frantz; Bowles, Kenneth J. (Technical Monitor)

2001-01-01

The main objective of this NASA FAR project is to conduct ultrasonic assessment of impact-induced damage and microcracking in polymer matrix composites at various temperatures. It is believed that the proposed study of impact damage assessment on polymer matrix composites will benefit several NASA missions and current interests, such as ballistic impact testing of composite fan containment and high strain rate deformation modeling of polymer matrix composites. Impact-induced damage mechanisms in GLARE and ARALL fiber-metal laminates subject to instrumented drop-weight impacts at various temperatures were studied. GLARE and ARALL are hybrid composites made of alternating layers of aluminum and glass (for GLARE) and aramid- (for ARALL) fiber-reinforced epoxy. Damage in pure aluminum panels impacted by foreign objects was mainly characterized by large plastic deformation surrounding a deep penetration dent. On the other hand, plastic deformation in fiber-metal laminates was often not as severe although the penetration dent was still produced. The more stiff fiber-reinforced epoxy layers provided better bending rigidity; thus, enhancing impact damage tolerance. Severe cracking, however, occurred due to the use of these more brittle fiber-reinforced epoxy layers. Fracture patterns, e.g., crack length and delamination size, were greatly affected by the lay-up configuration rather than by the number of layers, which implies that thickness effect was not significant for the panels tested in this study. Immersion ultrasound techniques were then used to assess damages generated by instrumented drop-weight impacts onto these fiber-metal laminate panels as well as 6061-T6 aluminum/cast acrylic sandwich plates adhered by epoxy. Depending on several parameters, such as impact velocity, mass, temperature, laminate configuration, sandwich construction, etc., various types of impact damage were observed, including plastic deformation, radiating cracks emanating from the impact site, ring cracks surrounding the impact site, partial and full delamination, and combinations of these damages.

Avidin as a Model for Charge Driven Transport into Cartilage and Drug Delivery for treating Early Stage Post-traumatic Osteoarthritis

PubMed Central

Bajpayee, Ambika G.; Wong, Cliff R.; Bawendi, Moungi G.; Frank, Eliot H.; Grodzinsky, Alan J.

2013-01-01

Local drug delivery into cartilage remains a challenge due to its dense extracellular matrix of negatively charged proteoglycans enmeshed within a collagen fibril network. The high negative fixed charge density of cartilage offers the unique opportunity to utilize electrostatic interactions to augment transport, binding and retention of drug carriers. With the goal of developing particle-based drug delivery mechanisms for treating post-traumatic osteoarthritis, our objectives were, first, to determine the size range of a variety of solutes that could penetrate and diffuse through normal cartilage and enzymatically treated cartilage to mimic early stages of OA, and second, to investigate the effects of electrostatic interactions on particle partitioning, uptake and binding within cartilage using the highly positively charged protein, Avidin, as a model. Results showed that solutes having a hydrodynamic diameter ≤ 10 nm can penetrate into the full thickness of cartilage explants while larger sized solutes were trapped in the tissue’s superficial zone. Avidin had a 400-fold higher uptake than its neutral same-sized counterpart, NeutrAvidin, and >90% of the absorbed Avidin remained within cartilage explants for at least 15 days. We report reversible, weak binding (KD ~150 μM) of Avidin to intratissue sites in cartilage. The large effective binding site density (NT ~ 2920 μM) within cartilage matrix facilitates Avidin’s retention, making its structure suitable for particle based drug delivery into cartilage. PMID:24120044

Impact of frequency and polarization diversity on a terahertz radar's imaging performance

NASA Astrophysics Data System (ADS)

Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria

2011-05-01

The Jet Propulsion Laboratory's 675 GHz, 25 m standoff imaging radar can achieve >1 Hz real time frame rates over 40x40 cm fields of view for rapid detection of person-borne concealed weapons. In its normal mode of operation, the radar generates imagery based solely on the time-of-flight, or range, between the radar and target. With good clothing penetration at 675 GHz, a hidden object will be detectable as an anomaly in the range-to-surface profile of a subject. Here we report on results of two modifications in the radar system that were made to asses its performance using somewhat different detection approaches. First, the radar's operating frequency and bandwidth were cut in half, to 340 GHz and 13 GHz, where there potential system advantages include superior transmit power and clothing penetration, as well as a lower cost of components. In this case, we found that the twofold reduction in range and cross-range resolution sharply limited the quality of through-clothes imagery, although some improvement is observed for detection of large targets concealed by very thick clothing. The second radar modification tested involved operation in a fully polarimetric mode, where enhanced image contrast might occur between surfaces with different material or geometric characteristics. Results from these tests indicated that random speckle dominates polarimetric power imagery, making it an unattractive approach for contrast improvement. Taken together, the experiments described here underscore the primary importance of high resolution imaging in THz radar applications for concealed weapons detection.

Enabling kinetic micro-penetrator technology for Solar System research

NASA Astrophysics Data System (ADS)

Gowen, R. A.

2008-09-01

Whilst the concept of high speed impacting penetrator probes is not new, recent highly successful ground test results have considerably improved the perception that these can be a viable and useful addition to the current toolbox of planetary probes. Previous developments only led to a single deployment (Deep Space-2 to Mars on the ill fated NASA Mars Polar Lander mission in 1999) where neither the soft lander nor penetrator was ever heard from, which is not a logical basis for dismissing penetrator technology. Other space penetrator programmes have included the Russian Mars'96 ~80m/s penetrators for which the whole mission was lost before the spacecraft left Earth orbit, and the Japanese Lunar-A program which was cancelled after a lengthy development program which however saw multiple successful ground trials. The Japanese penetrators were designed for ~300m/s impact. The current UK penetrator developments are actively working towards full space qualification for a Lunar penetrators (MoonLITE mission), which would also provide a significant technical demonstration towards the development of smaller, shorter lived penetrators for exploring other solar system objects. We are advocating delivered micro-penetrators in the mass range ~4-10Kg, (preceded by ~13Kg Lunar penetrator MoonLITE development program), impacting at around 100-500m/s and carrying a scientific payload of around 2Kg. Additional mass is required to deliver the probes from `orbit' to surface which is dependent upon the particular planetary body in question. The mass per descent module therefore involves and additional element which, for a descent through an atmosphere could be quite modest, while for a flyby deployment, can be substantial. For Europa we estimate a descent module mass of ~13 Kg, while for Enceladus the value is ~40Kg for Enceladus since a deceleration of ~3.8 kms-1 is needed from a Titan orbit. The delivery system could consist of a rocket deceleration motor and attitude control system, to e.g. simple fins for bodies with atmospheres Whilst a 2Kg payload may be considered to be very low mass we propose that it is sufficient to carry out a comprehensive range of scientific investigations of the highest priority, and can include a chemistry package (e.g. mass spectrometer with drill, doped optical fibres), micro-seismometers and accelerometers, together with a package of environment sensors capable of measuring temperature, heat flow, dielectric constant, radiation levels, magnetic fields, and a descent camera. Other very low mass options also include a subsurface mineralogy/astrobiology camera; simple redox and pH instruments; and a beeping transmitter to allow radio interferometery from Earth to detect surface motions whether seismic or tidally induced. At present most of these payload instruments either have good space heritage but no impact qualification; are very simple; or have been fully space qualified with the previous space hardware developments. The UK penetrator consortium is currently actively pursuing a program to provide full space qualification for most of the above instruments, of which sensor elements of the mass spectrometer, prototype drill component, micro-seismometers, magnetometer, radiation sensors have currently survived the recent (May 2008) impact test at 310ms-1with a worst case 8- 10 degrees attack angle (offset between velocity vector and normal incidence angle) where forces in excess of 10Kgee were experienced. Such a payload is capable of significant sub-surface chemical inventory identification including refactory, organic materials; seismic investigations of the interior of active bodies; sub-surface mechanical information including layering from accelerometers and mineralogy/astrobiology camera, and ground truth from orbiting experiments such as dielectric constant which is particularly relevant to orbiting ground penetrating radar measurements. A descent camera can provide both impact site geophysical context as well as public media images. These penetrators are ideal for vangard investigations of planetary bodies, or exploration of multiple sites where low mass is of particular benefit. They can provide a substantial scientific standalone capability; ground truth to orbiting instrument; provide concurrent missions with key data at other geographical locations; and provide broad scientific information to guide follow-on missions to more highly focused science investigations with more capable soft landed scientific instruments. Solar system bodies which are applicable to penetrator investigations are numerous and include the Moon, and the current ESA Cosmic Vision proposed missions to Europa, Titan and Enceladus. Other bodies would also include Near Earth Objects (NEOs) for which accelerometers in particular could be EPSC Abstracts, Vol. 3, EPSC2008-A-00526, 2008 European Planetary Science Congress, Author(s) 2008 instrumental in determining whether such objects are solid rock or loose rubble piles as currently thought. Though Mars already has a fairly mature and heavy investigative program both current and planned, the ability to implant a planet wide seismic network would be advantageous as well as extending astrobiologic investigations to new sites. The MoonLITE mission is a proposed UK led lunar mission which is planned to complete a phase-A study in the spring of 2009 with a possible launch in 2013. MoonLITE would comprise of 4 13 kg penetrators distributed widely upon the Moon including shaded polar craters and the far side. An orbiter would relay signals between penetrator and Earth. Key additional steps to enable exploration of other solar system bodies includes impact into harder (icy) and rough surfaces; increased radiation environments; and communications where a trailing aerial to mitigate signal attenuation through more heavily attenuating materials may be more prevalent. Also, significant is the desire to reduce the probe mass, which is envisaged to arise from a reduced lifetime of hours to weeks compared with ~1 year on the Moon, and by adopting new materials and technologies. Delivery of the probes is also likely to differ for each world, whether airless or with atmosphere, and the technology to deliver smaller probes, and with widely varying delta-V requirements requiring shorter and longer flight times. Surprisingly, operation in very cold environments is shared with the Moon's permanently shadowed craters.

Nail injury to the brain obfuscated by a fall from height - homicide or suicide? a case report.

PubMed

Aggrawal, Anil; Pradhan, Monisha; Sreenivas, M

2015-01-01

Penetrating head injuries caused by unconventional objects such as a nail generate speculation and doubt regarding the manner of infliction. We report a case of a 24-year-old woman alleged to have committed suicide by a fall from height. Autopsy revealed an unprecedented penetrating intracranial injury caused by a nail over the right temporal region, confounding the manner of death. The underlying intersecting pattern of fractures determined the chronological sequence of events. In this paper, we discuss the manner, incidence and pathology of nail injuries to the brain. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Cratering and penetration experiments in teflon targets at velocities from 1 to 7 km/s

NASA Technical Reports Server (NTRS)

Horz, Friedrich; Cintala, Mark; Bernhard, Ronald P.; Cardenas, Frank; Davidson, William; Haynes, Gerald; See, Thomas H.; Winkler, Jerry; Knight, Jeffrey

1994-01-01

Approximately 20 sq m of protective thermal blankets, largely composed of Teflon, were retrieved from the Long Duration Exposure Facility after the spacecraft spent approximately 5.7 years in space. Examination of these blankets revealed that they contained thousands of hypervelocity impact features ranging from micron-sized craters to penetration holes several millimeters in diameter. We conducted impact experiments to reproduce such features and to understand the relationships between projectile size and the resulting crater or penetration hole diameter over a wide range of impact velocities. Such relationships are needed to derive the size and mass frequency distribution and flux of natural and man-made particles in low-earth orbit. Powder propellant and light-gas guns were used to launch soda-lime glass spheres into pure Teflon targets at velocities ranging from 1 to 7 km/s. Target thickness varied over more than three orders of magnitude from finite halfspace targets to very thin films. Cratering and penetration of massive Teflon targets is dominated by brittle failure and the development of extensive spall zones at the target's front and, if penetrated, the target's rear side. Mass removal by spallation at the back side of Teflon targets may be so severe that the absolute penetration hole diameter can become larger than that of a standard crater. The crater diameter in infinite halfspace Teflon targets increases, at otherwise constant impact conditions, with encounter velocity by a factor of V (exp 0.44). In contrast, the penetration hole size in very thin foils is essentially unaffected by impact velocity. Penetrations at target thicknesses intermediate to these extremes will scale with variable exponents of V. Our experimental matrix is sufficiently systematic and complete, up to 7 km/s, to make reasonable recommendations for velocity-scaling of Teflon craters and penetrations. We specifically suggest that cratering behavior and associated equations apply to all impacts in which the shock-pulse duration of the projectile is shorter than that assigned a unique projectile size, provided an impact velocity is known or assumed. This calibration seems superior to the traditional ballistic-limit approach.

Numerical Experiments of Counterflowiing Jet Effects on Supersonic Slender-Body Configurations

NASA Technical Reports Server (NTRS)

Venkatachari, Balaji Shankar; Mullane, Michael; Cheng, Gary C.; Chang, Chau-Lyan

2015-01-01

Previous studies have demonstrated that the use of counterflowing jets can greatly reduce the drag and heat loads on blunt-body geometries, especially when the long penetration mode jet condition can be established. Previously, the authors had done some preliminary numerical studies to determine the ability to establish long penetration mode jets on a typical Mach 1.6 slender configuration, and study its impact on the boom signature. The results indicated that a jet with a longer penetration length was required to achieve any impact on the boom signature of a typical Mach 1.6 slender configuration. This paper focuses on an in-depth parametric study, done using the space-time conservation element solution element Navier-Stokes flow solver, for investigating the effect of various counterflowing jet conditions/configurations on two supersonic slender-body models (cone-cylinder and quartic body of revolution). The study is aimed at gaining a better understanding of the relationship between the shock penetration length and reduction of drag and boom signature for these two supersonic slender-body configurations. Different jet flow rates, Mach numbers, nozzle jet exit diameters and jet-to-base diameter ratios were examined. The results show the characteristics of a short-to-long-to-short penetration-mode pattern with the increase of jet mass flow rates, observed across various counterflowing jet nozzle configurations. Though the optimal shock penetration length for potential boom-signature mitigation is tied to the long penetration mode, it often results in a very unsteady flow and leads to large oscillations of surface pressure and drag. Furthermore, depending on the geometry of the slender body, longer jet penetration did not always result in maximum drag reduction. For the quartic geometry, the maximum drag reduction corresponds well to the longest shock penetration length, while this was not the case for the cone-cylinder-as the geometry was already optimized for drag. Numerical results and assessments obtained from this parametric study along with the recommendation for future implementation of counterflowing jets as a means for drag and noise reduction are detailed in this paper.

[Fundamental biological model for trials of wound ballistics].

PubMed

Krajsa, J; Hirt, M

2006-10-01

The aim of our experiment was the testing of effects of common ammunition on usable and slightly accessible biological tissue thereby to create fundamental simple biological model for trials of wounded ballistic. Like objective tissue was elected biological material - pork and beef hind-limbs, pork head, pork bodily cavity. It was discovered that objective tissue is able to react to singles types of shots in all spectrum results namely simple smooth penetration wound as well as splintery fracture in dependence on kind of using ammunition. Pork hind-limb was evaluated like the most suitable biological material for given object.

Intuitive color-based visualization of multimedia content as large graphs

NASA Astrophysics Data System (ADS)

Delest, Maylis; Don, Anthony; Benois-Pineau, Jenny

2004-06-01

Data visualization techniques are penetrating in various technological areas. In the field of multimedia such as information search and retrieval in multimedia archives, or digital media production and post-production, data visualization methodologies based on large graphs give an exciting alternative to conventional storyboard visualization. In this paper we develop a new approach to visualization of multimedia (video) documents based both on large graph clustering and preliminary video segmenting and indexing.

Grid of the Future: Quantification of Benefits from Flexible Energy Resources in Scenarios With Extra-High Penetration of Renewable Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bebic, Jovan; Hinkle, Gene; Matic, Slobodan

2015-01-15

The main objective of this study is to quantify the entitlement for system benefits attainable by pervasive application of flexible energy resources in scenarios with extra-high penetration of renewable energy. The quantified benefits include savings in thermal energy and reduction of CO 2 emissions. Both are primarily a result of displacement of conventional thermal generation by renewable energy production, but there are secondary improvements that arise from lowering operating reserves, removing transmission constraints, and by partially removing energy-delivery losses due to energy production by distributed solar. The flexible energy resources in the context of this study include energy storage andmore » adjustable loads. The flexibility of both was constrained to a time horizon of one day. In case of energy storage this means that the state of charge is restored to the starting value at the end of each day, while for load this means that the daily energy consumed is maintained constant. The extra-high penetration of renewable energy in the context of this study means the level of penetration resulting in significant number of hours where instantaneous power output from renewable resources added to the power output from baseload nuclear fleet surpasses the instantaneous power consumption by the load.« less

Tomographic aspects of penetrating thoracic trauma: injuries from firearms and other weapons

PubMed Central

de Melo, Alessandro Severo Alves; Moreira, Luiza Beatriz Melo; Pessoa, Fernanda Miraldi Clemente; Saint-Martin, Nara; Ancilotti Filho, Roger; Souza Jr., Arthur Soares; Marchiori, Edson

2017-01-01

Objective The aim of this study was to analyze the various computed tomography findings in penetrating chest trauma, as well as to determine the frequency and extent of the lesions. Material and Methods We studied the computed tomography findings from 40 cases of penetrating thoracic trauma, of which 35 (85.8%) were gunshot wounds and 5 (14.2%) were caused by another type of weapon. Results Pulmonary lesions were found in 39 cases (97.5%), manifesting as contusions in 34 cases (85%), atelectasis in 8 (20%), lacerations in 1 (2.5%) and hematomas in 1 (2.5%). Hemothorax was seen in 31 cases (77.5%), and pneumothorax was seen in 22 cases (55%). Mediastinal lesions were observed in 8 cases (20%), including mediastinal hematoma in 3 cases (7.5%), hemopericardium in 3 (7.5%), and pneumomediastinum in 2 (5%). Diaphragmatic rupture was seen in 2 cases (5%). Conclusion In patients with penetrating thoracic trauma, computed tomography of the chest is an important tool for characterizing the affected organs and evaluating the path of injury, as well as the severity and extent of the lesions. The images obtained are also useful in estimating the risk of death and determining the best therapeutic approach. PMID:29307927

A preliminary assessment of the effects of heat flux distribution and penetration on the creep rupture of a reactor vessel lower head

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chu, T.Y.; Bentz, J.; Simpson, R.

1997-02-01

The objective of the Lower Head Failure (LHF) Experiment Program is to experimentally investigate and characterize the failure of the reactor vessel lower head due to thermal and pressure loads under severe accident conditions. The experiment is performed using 1/5-scale models of a typical PWR pressure vessel. Experiments are performed for various internal pressure and imposed heat flux distributions with and without instrumentation guide tube penetrations. The experimental program is complemented by a modest modeling program based on the application of vessel creep rupture codes developed in the TMI Vessel Investigation Project. The first three experiments under the LHF programmore » investigated the creep rupture of simulated reactor pressure vessels without penetrations. The heat flux distributions for the three experiments are uniform (LHF-1), center-peaked (LHF-2), and side-peaked (LHF-3), respectively. For all the experiments, appreciable vessel deformation was observed to initiate at vessel wall temperatures above 900K and the vessel typically failed at approximately 1000K. The size of failure was always observed to be smaller than the heated region. For experiments with non-uniform heat flux distributions, failure typically occurs in the region of peak temperature. A brief discussion of the effect of penetration is also presented.« less

Application of ground-penetrating radar technique to evaluate the waterfront location in hardened concrete

NASA Astrophysics Data System (ADS)

Rodríguez-Abad, Isabel; Klysz, Gilles; Martínez-Sala, Rosa; Balayssac, Jean Paul; Mené-Aparicio, Jesús

2016-12-01

The long-term performance of concrete structures is directly tied to two factors: concrete durability and strength. When assessing the durability of concrete structures, the study of the water penetration is paramount, because almost all reactions like corrosion, alkali-silica, sulfate, etc., which produce their deterioration, require the presence of water. Ground-penetrating radar (GPR) has shown to be very sensitive to water variations. On this basis, the objective of this experimental study is, firstly, to analyze the correlation between the water penetration depth in concrete samples and the GPR wave parameters. To do this, the samples were immersed into water for different time intervals and the wave parameters were obtained from signals registered when the antenna was placed on the immersed surface of the samples. Secondly, a procedure has been developed to be able to determine, from those signals, the reliability in the detection and location of waterfront depths. The results have revealed that GPR may have an enormous potential in this field, because excellent agreements were found between the correlated variables. In addition, when comparing the waterfront depths calculated from GPR measurements and those visually registered after breaking the samples, we observed that they totally agreed when the waterfront was more than 4 cm depth.

Penetrating School Strata Through Career Education (Grades 7 and 8).

ERIC Educational Resources Information Center

Bristol Public Schools, CT.

The career education curriculum guide for grades seven and eight contains activities that can be integrated with existing curriculum. For each activity, career education objectives are cited together with goals, materials, procedures, anticipated results, and evaluation. Career education activities are presented in the following areas: art,…

Evaluation of surface resistivity measurements as an alternative to the rapid chloride permeability test for quality assurance and acceptance : technical summary.

DOT National Transportation Integrated Search

2011-07-01

This project investigated the use of a surface resistivity device as an indication of concretes ability to resist chloride ion penetration for use in quality assurance (QA) and acceptance of high performance concrete (HPC). : The objectives of thi...

38 CFR 4.56 - Evaluation of muscle disabilities.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., the cardinal signs and symptoms of muscle disability are loss of power, weakness, lowered threshold of... signs or symptoms of muscle disability as defined in paragraph (c) of this section. (iii) Objective... injury. Through and through or deep penetrating wound of short track from a single bullet, small shell or...

38 CFR 4.56 - Evaluation of muscle disabilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., the cardinal signs and symptoms of muscle disability are loss of power, weakness, lowered threshold of... signs or symptoms of muscle disability as defined in paragraph (c) of this section. (iii) Objective... injury. Through and through or deep penetrating wound of short track from a single bullet, small shell or...

Air-launched GPR evaluation for rapid assessment of MoDOT bridge decks.

DOT National Transportation Integrated Search

2015-03-01

This study demonstrated the utility of the air-launched ground penetrating radar (GPR) tool in terms of : evaluating the condition of MoDOT bridge decks. The objective was to confirm that the air-launched GPR : tool can be implemented as a part of a ...

Seeking Redemptive Diversity in Christian Institutions of Higher Education: Challenges and Hopes from within

ERIC Educational Resources Information Center

Abadeer, Adel S.

2009-01-01

Diversity and cross-cultural engagements should be among the leading forces and objectives in Christian institutions of higher education. The increasing influence and penetration of globalization and the melting pot of contemporary societies necessitate that Christian colleges and universities revisit their heritage, mission statements, and…

Plodia interpunctella and Trogoderma variabile larval penetration and invasion of methoprene-treated foil packaging

USDA-ARS?s Scientific Manuscript database

Packaged food products inside retail stores and food warehouses are susceptible to infestation by stored-product insects. The insect growth regulator methoprene can be impregnated onto packaging to help limit stored-product insect population development and prevent infestations. The objectives of t...

Use of JOINTBOND(R) as a center line joint stabilizer demonstration on I-95 N.B., Waterville to Clinton, Maine.

DOT National Transportation Integrated Search

2013-09-01

The objective of this study is to determine if JOINTBOND extends the useful life of the construction joint by : reducing permeability at the joint. : The manufacturer claims that JOINTBOND penetrates and fortifies the weakest area in new asphalt ...

High temperature superconductors: A technological revolution

NASA Technical Reports Server (NTRS)

1990-01-01

The objectives are to demonstrate the Meissner effect through magnetic levitation, to demonstrate one application of the Meissner effect, the low friction magnetic rotation bearing, and to demonstrate magnetic flux penetration and the Type II nature of ceramic superconductors via the stacking of the superconductor disks. Experimental equipment and procedures are described.

Two-material optimization of plate armour for blast mitigation using hybrid cellular automata

NASA Astrophysics Data System (ADS)

Goetz, J.; Tan, H.; Renaud, J.; Tovar, A.

2012-08-01

With the increased use of improvised explosive devices in regions at war, the threat to military and civilian life has risen. Cabin penetration and gross acceleration are the primary threats in an explosive event. Cabin penetration crushes occupants, damaging the lower body. Acceleration causes death at high magnitudes. This investigation develops a process of designing armour that simultaneously mitigates cabin penetration and acceleration. The hybrid cellular automaton (HCA) method of topology optimization has proven efficient and robust in problems involving large, plastic deformations such as crash impact. Here HCA is extended to the design of armour under blast loading. The ability to distribute two metallic phases, as opposed to one material and void, is also added. The blast wave energy transforms on impact into internal energy (IE) inside the solid medium. Maximum attenuation occurs with maximized IE. The resulting structures show HCA's potential for designing blast mitigating armour structures.

Effect of wind turbine generator model and siting on wind power changes out of large WECS arrays

NASA Technical Reports Server (NTRS)

Schleuter, R. A.; Park, G. L.; Lotfalian, M.; Dorsey, J.; Shayanfar, H.

1981-01-01

Methods of reducing the WECS generation change through selection of the wind turbine model for each site, selection of an appropriate siting configuration, and wind array controls are discussed. An analysis of wind generation change from an echelon and a farm for passage of a thunderstorm is presented. Reduction of the wind generation change over ten minutes is shown to reduce the increase in spinning reserve, unloadable generation and load following requirements on unit commitment when significant WECS generation is present and the farm penetration constraint is satisfied. Controls on the blade pitch angle of all wind turbines in an array or a battery control are shown to reduce both the wind generation change out of an array and the effective farm penetration in anticipation of a storm so that the farm penetration constraint may be satisfied.

Biomaterials as novel penetration enhancers for transdermal and dermal drug delivery systems.

PubMed

Chen, Yang; Wang, Manli; Fang, Liang

2013-01-01

The highly organized structure of the stratum corneum provides an effective barrier to the drug delivery into or across the skin. To overcome this barrier function, penetration enhancers are always used in the transdermal and dermal drug delivery systems. However, the conventional chemical enhancers are often limited by their inability to delivery large and hydrophilic molecules, and few to date have been routinely incorporated into the transdermal formulations due to their incompatibility and local irritation issues. Therefore, there has been a search for the compounds that exhibit broad enhancing activity for more drugs without producing much irritation. More recently, the use of biomaterials has emerged as a novel method to increase the skin permeability. In this paper, we present an overview of the investigations on the feasibility and application of biomaterials as penetration enhancers for transdermal or dermal drug delivery systems.

The Flow Induced by the Coalescence of Two Initially Stationary Drops

NASA Technical Reports Server (NTRS)

Nobari, M. R.; Tryggvason, G.

1994-01-01

The coalescence of two initially stationary drops of different size is investigated by solving the unsteady, axisymmetric Navier-Stokes equations numerically, using a Front-Tracking/Finite Difference method. Initially, the drops are put next to each other and the film between them ruptured. Due to surface tension forces, the drops coalesce rapidly and the fluid from the small drop is injected into the larger one. For low nondimensional viscosity, or Ohnesorge number, little mixing takes place and the small drop fluid forms a blob near the point where the drops touched initially. For low Ohnesorge number, on the other hand, the small drop forms a jet that penetrates far into the large drop. The penetration depth also depends on the size of the drops and shows that for a given fluid of sufficiently low viscosity, there is a maximum penetration depth for intermediate size ratios.

An investigation of chemically-induced improvement in saturation moisture characteristics of epoxies

NASA Technical Reports Server (NTRS)

Singh, J. J.; St.clair, T. L.; Stoakley, D. M.

1984-01-01

MY-720/DDS epoxy samples were treated with three selected chemical compounds to render the active H-sites inactive for moisture absorption. Treating the epoxy castings with acetyl chloride and dichlorodimethyl silane leads only to surface changes indicating that these molecules are too large to penetrate the epoxy castings. Boron trifluoride, on the other hand, does penetrate the epoxy chain as is indicated by the formation of green domains in the interior of the castings. However, the process of saturating the specimens with moisture appears to leach out the chemical additives--thereby nullifying their possible ameliorative effects.

Removal of cardiothoracic war-related shrapnel using video-assisted thoracoscopic surgery.

PubMed

Khalifa, Mohammed; Abu-Zidan, Fikri M; Khan, Navidul; Black, Edward

2017-07-01

This is the first report in the literature to describe removing war-related cardiothoracic shrapnel using video-assisted thoracoscopic surgery (VATS). War blast caused penetrating thoracic and extremity injuries in 30-year-old man. He was referred to our hospital after stabilization. Magnetic resonance imaging was required to evaluate brachial plexus injury. Large, penetrating shrapnel fragment in the right posterior chest wall, retained shrapnel in apex of the right lung, and another fragment in the pericardium were removed using VATS in staged approach. Postoperative period was uneventful. VATS is useful in managing complex, war-related cardiothoracic injuries.

Biochemical and physical factors affecting discoloration characteristics of 19 bovine muscles.

PubMed

McKenna, D R; Mies, P D; Baird, B E; Pfeiffer, K D; Ellebracht, J W; Savell, J W

2005-08-01

Steaks from muscles (n=19 from nine beef carcasses) were evaluated over the course of retail display (0-, 1-, 2-, 3-, 4- or 5-d) for objective measures of discoloration (metmyoglobin, oxymyoglobin, L*-, a*-, and b*-values), reducing ability (metmyoglobin reductase activity (MRA), resistance to induced metmyoglobin formation (RIMF), and nitric oxide metmyoglobin reducing ability (NORA)), oxygen consumption rate (OCR), oxygen penetration depth, myoglobin content, oxidative rancidity, and pH. Muscles were grouped according to objective color measures of discoloration. M. longissimus lumborum, M. longissimus thoracis, M. semitendinosus, and M. tensor fasciae latae were grouped as "high" color stability muscles, M. semimembranosus, M. rectus femoris, and M. vastus lateralis were grouped as "moderate" color stability muscles, M. trapezius, M. gluteus medius, and M. latissimus dorsi were grouped as "intermediate" color stability muscles, M. triceps brachi - long head, M. biceps femoris, M. pectoralis profundus, M. adductor, M. triceps brachi - lateral head, and M. serratus ventralis were grouped as "low" color stability muscles, and M. supraspinatus, M. infraspinatus, and M. psoas major were grouped as "very low" color stability muscles. Generally, muscles of high color stability had high RIMF, nitric oxide reducing ability, and oxygen penetration depth and possessed low OCRs, myoglobin content, and oxidative rancidity. In contrast, muscles of low color stability had high MRA, OCRs, myoglobin content, and oxidative rancidity and low RIMF, NORA, and oxygen penetration depth. Data indicate that discoloration differences between muscles are related to the amount of reducing activity relative to the OCR.

Plastic footwear for leprosy.

PubMed

Antia, N H

1990-03-01

The anaesthetic foot in leprosy poses the most major problem in the rehabilitation of its patients. Various attempts have been made to produce protective footwear such as the microcellular rubber-car-tyre sandals. Unfortunately these attempts have had little success on a large scale because of the inability to produce them in large numbers and the stigma attached to such unusual footwear. While such footwear may be superior to the 'tennis' shoe in protecting the foot from injury by the penetration of sharp objects, it fails to distribute the weight-bearing forces which is the major cause of plantar damage and ulceration in the anaesthetic foot. This can be achieved by providing rigidity to the sole, as demonstrated by the healing of ulcers in plaster of paris casts or the rigid wooden clog. A new type of moulded plastic footwear has been evolved in conjunction with the plastic footwear industry which provides footwear that can be mass produced at a low price and which overcomes the stigma of leprosy. Controlled rigidity is provided by the incorporation of a spring steel shank between the sponge insole and the hard wearing plastic sole. Trials have demonstrated both the acceptability of the footwear and its protective effects as well as its hard wearing properties.

Geohydrology of volcanic tuff penetrated by test well UE-25b#1, Yucca Mountain, Nye County, Nevada

USGS Publications Warehouse

Lahoud, R.G.; Lobmeyer, D.H.; Whitfield, M.S.

1984-01-01

Test well UE-25bNo1, located on the east side of Yucca Mountain in the southwestern part of the Nevada Test Site, was drilled to a total depth of 1,220 meters and hydraulically tested as part of a program to evaluate the suitability of Yucca Mountain as a nuclear-waste repository. The well penetrated almost 46 meters of alluvium and 1,174 meters of Tertiary volcanic tuffs. The composite hydraulic head for aquifers penetrated by the well was 728.9 meters above sea level (471.4 meters below land surface) with a slight decrease in loss of hydraulic head with depth. Average hydraulic conductivities for stratigraphic units determined from pumping tests, borehole-flow surveys, and packer-injection tests ranged from less than 0.001 meter per day for the Tram Member of the Crater Flat Tuff to 1.1 meters per day for the Bullfrog Member of the Crater Flat Tuff. The small values represented matrix permeability of unfractured rock; the large values probably resulted from fracture permeability. Chemical analyses indicated that the water is a soft sodium bicarbonate type, slightly alkaline, with large concentrations of dissolved silica and sulfate. Uncorrected carbon-14 age dates of the water were 14,100 and 13,400 years. (USGS)

Characterizing and analyzing ramping events in wind power, solar power, load, and netload

DOE PAGES

Cui, Mingjian; Zhang, Jie; Feng, Cong; ...

2017-04-07

Here, one of the biggest concerns associated with integrating a large amount of renewable energy into the power grid is the ability to handle large ramps in the renewable power output. For the sake of system reliability and economics, it is essential for power system operators to better understand the ramping features of renewable, load, and netload. An optimized swinging door algorithm (OpSDA) is used and extended to accurately and efficiently detect ramping events. For wind power ramps detection, a process of merging 'bumps' (that have a different changing direction) into adjacent ramping segments is included to improve the performancemore » of the OpSDA method. For solar ramps detection, ramping events that occur in both clear-sky and measured (or forecasted) solar power are removed to account for the diurnal pattern of solar generation. Ramping features are extracted and extensively compared between load and netload under different renewable penetration levels (9.77%, 15.85%, and 51.38%). Comparison results show that (i) netload ramp events with shorter durations and smaller magnitudes occur more frequently when renewable penetration level increases, and the total number of ramping events also increases; and (ii) different ramping characteristics are observed in load and netload even with a low renewable penetration level.« less

Residential Solar PV Systems in the Carolinas: Opportunities and Outcomes.

PubMed

Alqahtani, Bandar Jubran; Holt, Kyra Moore; Patiño-Echeverri, Dalia; Pratson, Lincoln

2016-02-16

This paper presents a first-order analysis of the feasibility and technical, environmental, and economic effects of large levels of solar photovoltaic (PV) penetration within the services areas of the Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP). A PV production model based on household density and a gridded hourly global horizontal irradiance data set simulates hourly PV power output from roof-top installations, while a unit commitment and real-time economic dispatch (UC-ED) model simulates hourly system operations. We find that the large generating capacity of base-load nuclear power plants (NPPs) without ramping capability in the region limits PV integration levels to 5.3% (6510 MW) of 2015 generation. Enabling ramping capability for NPPs would raise the limit of PV penetration to near 9% of electricity generated. If the planned retirement of coal-fired power plants together with new installations and upgrades of natural gas and nuclear plants materialize in 2025, and if NPPs operate flexibly, then the share of coal-fired electricity will be reduced from 37% to 22%. A 9% penetration of electricity from PV would further reduce the share of coal-fired electricity by 4-6% resulting in a system-wide CO2 emissions rate of 0.33 to 0.40 tons/MWh and associated abatement costs of 225-415 (2015$ per ton).

Prediction methods of spudcan penetration for jack-up units

NASA Astrophysics Data System (ADS)

Zhang, Ai-xia; Duan, Meng-lan; Li, Hai-ming; Zhao, Jun; Wang, Jian-jun

2012-12-01

Jack-up units are extensively playing a successful role in drilling engineering around the world, and their safety and efficiency take more and more attraction in both research and engineering practice. An accurate prediction of the spudcan penetration depth is quite instrumental in deciding on whether a jack-up unit is feasible to operate at the site. The prediction of a too large penetration depth may lead to the hesitation or even rejection of a site due to potential difficulties in the subsequent extraction process; the same is true of a too small depth prediction due to the problem of possible instability during operation. However, a deviation between predictive results and final field data usually exists, especially when a strong-over-soft soil is included in the strata. The ultimate decision sometimes to a great extent depends on the practical experience, not the predictive results given by the guideline. It is somewhat risky, but no choice. Therefore, a feasible predictive method for the spudcan penetration depth, especially in strata with strong-over-soft soil profile, is urgently needed by the jack-up industry. In view of this, a comprehensive investigation on methods of predicting spudcan penetration is executed. For types of different soil profiles, predictive methods for spudcan penetration depth are proposed, and the corresponding experiment is also conducted to validate these methods. In addition, to further verify the feasibility of the proposed methods, a practical engineering case encountered in the South China Sea is also presented, and the corresponding numerical and experimental results are also presented and discussed.

Effect of Microstructure Constraints on the Homogenized Elastic Constants of Elastomeric Sylgard/GMB Syntactic Foam.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Judith Alice; Steck, Daniel; Brown, Judith Alice

Previous numerical studies of Sylgard filled with glass microballoons (GMB) have relied on various microstructure idealizations to achieve a large range of volume fractions with high mesh quality. This study investigates how different microstructure idealizations and constraints affect the apparent homogenized elastic constants in the virgin state of the material, in which all GMBs are intact and perfectly bonded to the Sylgard matrix, and in the fully damaged state of the material in which all GMBs are destroyed. In the latter state, the material behaves as an elastomeric foam. Four microstructure idealizations are considered relating to how GMBs are packedmore » into a representative volume element (RVE): (1) no boundary penetration nor GMB-GMB overlap, (2) GMB-GMB overlap, (3) boundary penetration, and (4) boundary penetration and GMB-GMB overlap. First order computational homogenization with kinematically uniform displacement boundary conditions (KUBCs) was employed to determine the homogenized (apparent) bulk and shear moduli for the four microstructure idealizations in the intact and fully broken GMB material states. It was found that boundary penetration has a significant effect on the shear modulus for microstructures with intact GMBs, but that neither boundary penetration nor GMB overlap have a significant effect on homogenized properties for microstructures with fully broken GMBs. The primary conclusion of the study is that future investigations into Sylgard/GMB micromechanics should either force GMBs to stay within the RVE fully and/or use periodic BCs (PBCs) to eliminate the boundary penetration issues. The implementation of PBCs requires the improvement of existing tools in Sandia’s Sierra/SM code.« less

Comparison of wavelength-dependent penetration depths of lasers in different types of skin in photodynamic therapy

NASA Astrophysics Data System (ADS)

Mustafa, F. H.; Jaafar, M. S.

2013-03-01

The determination of the penetration depth of laser light with different sources wavelengths into human skin is one of the preconditions of improving the photodynamic therapy (PDT) procedure for skin diseases. This research is planned to explore which wavelengths would be the most advantageous for use in PDT for superficial skin diseases, and to demonstrate that the red laser exposure of 635 nm wavelength is a suitable choice for all skin types in PDT. A realistic skin model (RSM) in the Advanced Systems Analysis Program (ASAP) software has been used to create different types of skin and to simulate laser sources with wavelengths of 635, 532, 405, 365, 308 and 295 nm. The penetration depths of different kinds of laser into the skin as well as their transmission have been calculated. Comparison of the depth of penetration of different wavelengths for all types of skin has been made. A large variation is found in the penetration depth of laser lights in all skin types. The transmission of lasers on the epidermis and dermis in different skin types occur, and the transmission dose changes significantly with the skin depths. The results of the present study provide a basis for understanding the penetration depth of laser in various skin colors and the responses of the skin to laser to improve dose-drug activation in PDT. The differences in spectral transmission between the red laser and the other lasers suggest that the red laser could be a suitable laser for all skin types.

Influence of corrosion layers on quantitative analysis

NASA Astrophysics Data System (ADS)

Denker, A.; Bohne, W.; Opitz-Coutureau, J.; Rauschenberg, J.; Röhrich, J.; Strub, E.

2005-09-01

Art historians and restorers in charge of ancient metal objects are often reluctant to remove the corrosion layer evolved over time, as this would change the appearance of the artefact dramatically. Therefore, when an elemental analysis of the objects is required, this has to be done by penetrating the corrosion layer. In this work the influence of corrosion was studied on Chinese and Roman coins, where removal of oxidized material was possible. Measurements on spots with and without corrosion are presented and the results discussed.

Renewable Electricity Futures. Operational Analysis of the Western Interconnection at Very High Renewable Penetrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brinkman, Gregory

2015-09-01

The Renewable Electricity Futures Study (RE Futures)--an analysis of the costs and grid impacts of integrating large amounts of renewable electricity generation into the U.S. power system--examined renewable energy resources, technical issues regarding the integration of these resources into the grid, and the costs associated with high renewable penetration scenarios. These scenarios included up to 90% of annual generation from renewable sources, although most of the analysis was focused on 80% penetration scenarios. Hourly production cost modeling was performed to understand the operational impacts of high penetrations. One of the conclusions of RE Futures was that further work was necessarymore » to understand whether the operation of the system was possible at sub-hourly time scales and during transient events. This study aimed to address part of this by modeling the operation of the power system at sub-hourly time scales using newer methodologies and updated data sets for transmission and generation infrastructure. The goal of this work was to perform a detailed, sub-hourly analysis of very high penetration scenarios for a single interconnection (the Western Interconnection). It focused on operational impacts, and it helps verify that the operational results from the capacity expansion models are useful. The primary conclusion of this study is that sub-hourly operation of the grid is possible with renewable generation levels between 80% and 90%.« less

Single wall penetration equations

NASA Technical Reports Server (NTRS)

Hayashida, K. B.; Robinson, J. H.

1991-01-01

Five single plate penetration equations are compared for accuracy and effectiveness. These five equations are two well-known equations (Fish-Summers and Schmidt-Holsapple), two equations developed by the Apollo project (Rockwell and Johnson Space Center (JSC), and one recently revised from JSC (Cour-Palais). They were derived from test results, with velocities ranging up to 8 km/s. Microsoft Excel software was used to construct a spreadsheet to calculate the diameters and masses of projectiles for various velocities, varying the material properties of both projectile and target for the five single plate penetration equations. The results were plotted on diameter versus velocity graphs for ballistic and spallation limits using Cricket Graph software, for velocities ranging from 2 to 15 km/s defined for the orbital debris. First, these equations were compared to each other, then each equation was compared with various aluminum projectile densities. Finally, these equations were compared with test results performed at JSC for the Marshall Space Flight Center. These equations predict a wide variety of projectile diameters at a given velocity. Thus, it is very difficult to choose the 'right' prediction equation. The thickness of a single plate could have a large variation by choosing a different penetration equation. Even though all five equations are empirically developed with various materials, especially for aluminum alloys, one cannot be confident in the shield design with the predictions obtained by the penetration equations without verifying by tests.

Managed care penetration and other factors affecting computerized physician order entry in the ambulatory setting.

PubMed

Menachemi, Nir; Ford, Eric W; Chukmaitov, Askar; Brooks, Robert G

2006-12-01

To estimate the current uses level of ambulatory computerized physician order entry (A-CPOE) among physicians and to examine the relationship of managed care penetration as well as other market and practice characteristics to use of A-CPOE by physicians. This study uses both primary and secondary data sources. The primary data source was a large-scale survey of physicians' use of information technologies in Florida. Secondary data on managed care penetration were obtained from the Florida Agency for Health Care Administration, and other market-level data were extracted from the area resource file. A hierarchical logistic regression model was used to examine the correlation of county-level and practice-level characteristics with physicians' self-reported use of A-CPOE systems. Overall, 1360 physicians (32.4%) indicated use of an A-CPOE system. Findings suggest that 1% more managed care penetration was associated with 2.1% lower use of A-CPOE (P = .003). Additionally, practice size, multispecialty affiliation, and primary care practice were significantly and positively correlated with the use of A-CPOE. Physician age was negatively associated with A-CPOE use. Managed care organizations may experience significant financial savings from A-CPOE use by physicians; however, managed care penetration in a community negatively affects A-CPOE use among physicians in their practices. Further study regarding the causal nature of this association is warranted.

Comparison of edge chipping resistance of PFM and veneered zirconia specimens

PubMed Central

Quinn, Janet B.; Sundar, Veeraraghavan; Parry, Edward E.; Quinn, George D.

2011-01-01

Objectives To investigate the chipping resistance of veneered zirconia specimens and compare it to the chipping resistance of porcelain fused to metal (PFM) specimens. Methods Veneered zirconia and PFM bar specimens were prepared in clinically relevant thicknesses. The specimen edges were chipped with different magnitude forces, producing chips of various sizes. The range of sizes included small chips that did not penetrate all the way through the veneers to the substrates, and also chips that were very large and reached the zirconia or metal substrates. The relationship between force magnitude and chip size (edge distance) was graphed. The resulting curves were compared for the veneered zirconia and PFM specimens. Knoop hardness vs. force graphs for the veneers and substrates were also obtained. Results The zirconia and PFM veneer chipping data followed a power law (coefficient of determination, R2 > 0.93) as expected from the literature. The curves overlapped within the combined data scatter, indicating similar resistance to chipping. The chips made in both types of specimens detached and did not penetrate into the substrate when they reached the veneer/substrate intersections. The hardness–load curves for the veneers and substrates all exhibited an indentation size effect (ISE) at low loads. The Knoop hardness values with uncertainties of ±one standard deviation at 4 N loads for the metal, zirconia, and the metal and zirconia veneers are: (2.02 ± 0.08, 12.01 ± 0.39, 4.24 ± 0.16 and 4.36 ± 0.02 GPa), respectively, with no statistically significant difference between the veneers (Tukey pairwise comparison at 0.95 family confidence). Significance This work indicates that a similar resistance to chipping might be expected for veneered zirconia and PFM restorations, in spite of the large difference in substrate hardness. Differences in susceptibility to chip spalling were not detected, but the chips in both specimen types detached off the sides in a similar manner instead of extending into the substrates. PMID:19748115

Ice Flow in the Humboldt, Petermann, and Ryder Glaciers, North Greenland

NASA Technical Reports Server (NTRS)

Joughin, I.; Fahnestock, M.; Kwok, R.; Gogineni, P.; Allen, C.

1998-01-01

Radar Interferometry, ice-penetrating radar profiles, and an elevation model are used to determine the catchment area, rates of ice discharge, and approximate states of balance for three large outlet glaciers in northeast Greenland.

Structural Damage Prediction and Analysis for Hypervelocity Impacts: Handbook

NASA Technical Reports Server (NTRS)

Elfer, N. C.

1996-01-01

This handbook reviews the analysis of structural damage on spacecraft due to hypervelocity impacts by meteoroid and space debris. These impacts can potentially cause structural damage to a Space Station module wall. This damage ranges from craters, bulges, minor penetrations, and spall to critical damage associated with a large hole, or even rupture. The analysis of damage depends on a variety of assumptions and the area of most concern is at a velocity beyond well controlled laboratory capability. In the analysis of critical damage, one of the key questions is how much momentum can actually be transfered to the pressure vessel wall. When penetration occurs without maximum bulging at high velocity and obliquities (if less momentum is deposited in the rear wall), then large tears and rupture may be avoided. In analysis of rupture effects of cylindrical geometry, biaxial loading, bending of the crack, a central hole strain rate and R-curve effects are discussed.

Simulation of the main physical processes in remote laser penetration with large laser spot size

DOE PAGES

Khairallah, S. A.; Anderson, A.; Rubenchik, A. M.; ...

2015-04-10

A 3D model is developed to simulate remote laser penetration of a 1mm Aluminum metal sheet with large laser spot size (~3x3cm²), using the ALE3D multi-physics code. The model deals with the laser-induced melting of the plate and the mechanical interaction between the solid and the melted part through plate elastic-plastic response. The effect of plate oscillations and other forces on plate rupture, the droplet formation mechanism and the influence of gravity and high laser power in further breaking the single melt droplet into many more fragments are analyzed. In the limit of low laser power, the numerical results matchmore » the available experiments. The numerical approach couples mechanical and thermal diffusion to hydrodynamics melt flow and accounts for temperature dependent material properties, surface tension, gravity and vapor recoil pressure.« less

Energy Technology Allocation for Distributed Energy Resources: A Technology-Policy Framework

NASA Astrophysics Data System (ADS)

Mallikarjun, Sreekanth

Distributed energy resources (DER) are emerging rapidly. New engineering technologies, materials, and designs improve the performance and extend the range of locations for DER. In contrast, constructing new or modernizing existing high voltage transmission lines for centralized generation are expensive and challenging. In addition, customer demand for reliability has increased and concerns about climate change have created a pull for swift renewable energy penetration. In this context, DER policy makers, developers, and users are interested in determining which energy technologies to use to accommodate different end-use energy demands. We present a two-stage multi-objective strategic technology-policy framework for determining the optimal energy technology allocation for DER. The framework simultaneously considers economic, technical, and environmental objectives. The first stage utilizes a Data Envelopment Analysis model for each end-use to evaluate the performance of each energy technology based on the three objectives. The second stage incorporates factor efficiencies determined in the first stage, capacity limitations, dispatchability, and renewable penetration for each technology, and demand for each end-use into a bottleneck multi-criteria decision model which provides the Pareto-optimal energy resource allocation. We conduct several case studies to understand the roles of various distributed energy technologies in different scenarios. We construct some policy implications based on the model results of set of case studies.

How Confocal Is Confocal Raman Microspectroscopy on the Skin? Impact of Microscope Configuration and Sample Preparation on Penetration Depth Profiles.

PubMed

Lunter, Dominique Jasmin

2016-01-01

The aim of the study was to elucidate the effect of sample preparation and microscope configuration on the results of confocal Raman microspectroscopic evaluation of the penetration of a pharmaceutical active into the skin (depth profiling). Pig ear skin and a hydrophilic formulation containing procaine HCl were used as a model system. The formulation was either left on the skin during the measurement, or was wiped off or washed off prior to the analysis. The microscope configuration was varied with respect to objectives and pinholes used. Sample preparation and microscope configuration had a tremendous effect on the results of depth profiling. Regarding sample preparation, the best results could be observed when the formulation was washed off the skin prior to the analysis. Concerning microscope configuration, the use of a 40 × 0.6 numerical aperture (NA) objective in combination with a 25-µm pinhole or a 100 × 1.25 NA objective in combination with a 50-µm pinhole was found to be advantageous. Complete removal of the sample from the skin before the analysis was found to be crucial. A thorough analysis of the suitability of the chosen microscope configuration should be performed before acquiring concentration depth profiles. © 2016 S. Karger AG, Basel.

Penetration depth of corneal cross-linking with riboflavin and UV-A (CXL) in horses and rabbits.

PubMed

Gallhoefer, Nicolin S; Spiess, Bernhard M; Guscetti, Franco; Hilbe, Monika; Hartnack, Sonja; Hafezi, Farhad; Pot, Simon A

2016-07-01

CXL penetration depth is an important variable influencing clinical treatment effect and safety. The purposes of this study were to determine the penetration depth of CXL in rabbit and equine corneas in epithelium-on and epithelium-off procedures and to assess an ex vivo fluorescent biomarker staining assay for objective assessment of CXL penetration depth. CXL treatment was performed according to a standardized protocol on 21 and 17 rabbit eyes and on 12 and 10 equine eyes with and without debridement, respectively. Control corneas were treated similarly, but not exposed to CXL. Hemicorneas were stained with either phalloidin and DAPI to visualize intracellular F-actin and nuclei, or with hematoxylin and eosin. Loss of actin staining was measured and compared between groups. Epithelium-off CXL caused a median actin cytoskeleton loss with a demarcation at 274 μm in rabbits and 173 μm in horses. In non-CXL-treated controls, we observed a median actin cytoskeleton loss with a demarcation at 134 μm in rabbits and 149 μm in horses. No effect was detected in the epithelium-on procedure. CXL penetration depth, as determined by a novel ex vivo fluorescent assay, shows clear differences between species. A distinct effect was observed following epithelium-off CXL treatment in the anterior stroma of rabbits, but no different effect was observed in horses in comparison with nontreated controls. Different protocols need to be established to effectively treat equine patients with infectious corneal disease. © 2015 American College of Veterinary Ophthalmologists.

Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anna Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, Susan L.; Cinson, Anthony D.; MacFarlan, Paul J.

2012-08-01

The objective of this investigation was to evaluate the efficacy of ultrasonic testing (UT) for primary water leak path assessments of reactor pressure vessel (RPV) upper head penetrations. Operating reactors have experienced leakage when stress corrosion cracking of nickel-based alloy penetrations allowed primary water into the annulus of the interference fit between the penetration and the low-alloy steel RPV head. In this investigation, UT leak path data were acquired for an Alloy 600 control rod drive mechanism nozzle penetration, referred to as Nozzle 63, which was removed from the North Anna Unit 2 reactor when the RPV head was replacedmore » in 2002. In-service inspection prior to the head replacement indicated that Nozzle 63 had a probable leakage path through the interference fit region. Nozzle 63 was examined using a phased-array UT probe with a 5.0-MHz, eight-element annular array. Immersion data were acquired from the nozzle inner diameter surface. The UT data were interpreted by comparing to responses measured on a mockup penetration with known features. Following acquisition of the UT data, Nozzle 63 was destructively examined to determine if the features identified in the UT examination, including leakage paths and crystalline boric acid deposits, could be visually confirmed. Additional measurements of boric acid deposit thickness and low-alloy steel wastage were made to assess how these factors affect the UT response. The implications of these findings for interpreting UT leak path data are described.« less

A 40-foot static cone penetrometer

USGS Publications Warehouse

Beard, R.M.; Lee, H.J.

1982-01-01

The Navy needs a lightweight device for testing seafloor soils to sub bottom depths of 12 meters in water depths to 60 meters. To meet this need a quasistatic cone penetration device that uses water jetting to reduce friction on the cone rod has been developed. This device is called the XSP-40. The 5-ton XSP-40 stands 15 meters tall and pushes a standard 5-ton cone into the seafloor. It is remotely controlled with an electronic unit on the deck of the support vessel. All cone outputs are recorded directly as a function of penetration depth with a strip chart recorder. A full suite of gauges is provided. on the electronic unit for monitoring the XSP-40's performance during a test .. About 40 penetration tests have been performed with very good success. The XSP-40 was field tested in Norton Sound, off the west coast of Alaska. The general objective, in addition to evaluation of the device, was to gather geotechnical information on sediments that may be involved in processes potentially hazardous to offshore development. Four example penetration records are presented from gas charged sediment zones and areas near the Yukon River delta. In general it was determined that soil classification from cone data agreed well with classifications from core samples. Relative densities of the silt-sand to sandy-silt soils were usually very high. The significance of these results are discussed with respect to storm wave, liquefaction. It is concluded that the XSP-40 is a durable and reliable piece of equipment capable of achieving penetration beyond that possible when not using the water jet system.

Abundance in Capital: Global Risk Sharing and Insurance in a Changing Financial Environment

NASA Astrophysics Data System (ADS)

Michel, Gero; Schaper, Christopher

2014-05-01

Insurance has played a viable role in the hedging of homeowners and commercial risks around the world. Countries that have significant penetration in insurance have in addition performed better after large regional or over-regional catastrophic losses. Insurance has hence increased the resilience of western societies. This is opposed to emerging or developing markets with low insurance penetration which have suffered significant drawbacks in their development after large catastrophic events. Examples include the recent Typhoon(s) in the Philippines and the 2010 Haiti earthquake. This presentation will provide insights into the opportunities, views and risk management features a global reinsurance company must assume in order to hedge and mitigate risk across the world. During the past year, an unprecedented amount of new capital has been entering the insurance market, looking for profitable investments outside the much wider capital market. Catastrophe insurance is seen as a valuable alternative to investing in assets that that have shown low returns and high correlation in the recent financial meltdown. The new capital is mostly deployed - or competing with already deployed capital - in the US where insurance penetration is already high. This is opposed to more than half of the world including all developing and most emerging countries which have low insurance penetration and often lack infrastructure hindering new capital to be deployed effectively. What is needed to overcome this obvious deficiency in capital supply and demand? One reason why it is difficult to deploy capital in developing countries is the lack of available exposure information and catastrophe models. This presentation sheds light on the potential science needs of our market and gives an overview of what is being done at Montpelier, a global reinsurance company, to understand catastrophe risk around the globe.

A Dense Poly(ethylene glycol) Coating Improves Penetration of Large Polymeric Nanoparticles within Brain Tissue

PubMed Central

Nance, Elizabeth A.; Woodworth, Graeme F.; Sailor, Kurt A.; Shih, Ting-Yu; Xu, Qingguo; Swaminathan, Ganesh; Xiang, Dennis; Eberhart, Charles; Hanes, Justin

2013-01-01

Prevailing opinion suggests that only substances up to 64 nm in diameter can move at appreciable rates through the brain extracellular space (ECS). This size range is large enough to allow diffusion of signaling molecules, nutrients, and metabolic waste products, but too small to allow efficient penetration of most particulate drug delivery systems and viruses carrying therapeutic genes, thereby limiting effectiveness of many potential therapies. We analyzed the movements of nanoparticles of various diameters and surface coatings within fresh human and rat brain tissue ex vivo and mouse brain in vivo. Nanoparticles as large as 114-nm in diameter diffused within the human and rat brain, but only if they were densely coated with poly(ethylene glycol) (PEG). Using these minimally adhesive PEG-coated particles, we estimated that human brain tissue ECS has some pores larger than 200 nm, and that more than one-quarter of all pores are ≥100 nm. These findings were confirmed in vivo in mice, where 40- and 100-nm, but not 200-nm, nanoparticles, spread rapidly within brain tissue, only if densely coated with PEG. Similar results were observed in rat brain tissue with paclitaxel-loaded biodegradable nanoparticles of similar size (85 nm) and surface properties. The ability to achieve brain penetration with larger nanoparticles is expected to allow more uniform, longer-lasting, and effective delivery of drugs within the brain, and may find use in the treatment of brain tumors, stroke, neuroinflammation, and other brain diseases where the blood-brain barrier is compromised or where local delivery strategies are feasible. PMID:22932224

Solar radiation, phytoplankton pigments and the radiant heating of the equatorial Pacific warm pool

NASA Technical Reports Server (NTRS)

Siegel, David A.; Ohlmann, J. Carter; Washburn, Libe; Bidigare, Robert R.; Nosse, Craig T.; Fields, Erik; Zhou, Yimei

1995-01-01

Recent optical, physical, and biological oceanographic observations are used to assess the magnitude and variability of the penetrating flux of solar radiation through the mixed layer of the warm water pool (WWP) of the western equatorial Pacific Ocean. Typical values for the penetrative solar flux at the climatological mean mixed layer depth for the WWP (30 m) are approx. 23 W/sq m and are a large fraction of the climatological mean net air-sea heat flux (approx. 40 W/sq m). The penetrating solar flux can vary significantly on synoptic timescales. Following a sustained westerly wind burst in situ solar fluxes were reduced in response to a near tripling of mixed layer phytoplankton pigment concentrations. This results in a reduction in the penetrative flux at depth (5.6 W/sq m at 30 m) and corresponds to a biogeochemically mediated increase in the mixed layer radiant heating rate of 0.13 C per month. These observations demonstrate a significant role of biogeochemical processes on WWP thermal climate. We speculate that this biogeochemically mediated feedback process may play an important role in enhancing the rate at which the WWP climate system returns to normal conditions following a westerly wind burst event.

Cooperative Vehicular Traffic Monitoring in Realistic Low Penetration Scenarios: The COLOMBO Experience

PubMed Central

Caselli, Federico; Corradi, Antonio

2018-01-01

The relevance of effective and efficient solutions for vehicle traffic surveillance is widely recognized in order to enable advanced strategies for traffic management, e.g., based on dynamically adaptive and decentralized traffic light management. However, most related solutions in the literature, based on the powerful enabler of cooperative vehicular communications, assume the complete penetration rate of connectivity/communication technologies (and willingness to participate in the collaborative surveillance service) over the targeted vehicle population, thus making them not applicable nowadays. The paper originally proposes an innovative solution for cooperative traffic surveillance based on vehicular communications capable of: (i) working with low penetration rates of the proposed technology and (ii) of collecting a large set of monitoring data about vehicle mobility in targeted areas of interest. The paper presents insights and lessons learnt from the design and implementation work of the proposed solution. Moreover, it reports extensive performance evaluation results collected on realistic simulation scenarios based on the usage of iTETRIS with real traces of vehicular traffic of the city of Bologna. The reported results show the capability of our proposal to consistently estimate the real vehicular traffic even with low penetration rates of our solution (only 10%). PMID:29522427

DOE Office of Scientific and Technical Information (OSTI.GOV)

Funsten, Herbert O.; Harper, Ronnie W.; Dors, Eric E.

Channel electron multiplier (CEM) and microchannel plate (MCP) detectors are routinely used in space instrumentation for measurement of space plasmas. Here, our goal is to understand the relative sensitivities of these detectors to penetrating radiation in space, which can generate background counts and shorten detector lifetime. We use 662 keV γ-rays as a proxy for penetrating radiation such as γ-rays, cosmic rays, and high-energy electrons and protons that are ubiquitous in the space environment. We find that MCP detectors are ~20 times more sensitive to 662 keV γ-rays than CEM detectors. This is attributed to the larger total area ofmore » multiplication channels in an MCP detector that is sensitive to electronic excitation and ionization resulting from the interaction of penetrating radiation with the detector material. In contrast to the CEM detector, whose quantum efficiency ε γ for 662 keVγ -rays is found to be 0.00175 and largely independent of detector bias, the quantum efficiency of the MCP detector is strongly dependent on the detector bias, with a power law index of 5.5. Lastly, background counts in MCP detectors from penetrating radiation can be reduced using MCP geometries with higher pitch and smaller channel diameter.« less

Large magnetic penetration depth and thermal fluctuations in a superconducting Ca10(Pt3As8)[(Fe1 xPtx)2As2]5 (x = 0.097) single crystal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim J.; Nazaretski E.; Ronning, F.

2012-05-18

We have measured the temperature dependence of the absolute value of the magnetic penetration depth {lambda}(T) in a Ca{sub 10}(Pt{sub 3}As{sub 8})[(Fe{sub 1-x}Pt{sub x}){sub 2}As{sub 2}]{sub 5} (x = 0.097) single crystal using a low-temperature magnetic force microscope (MFM). We obtain {lambda}{sub ab}(0) {approx} 1000 nm via extrapolating the data to T = 0. This large {lambda} and pronounced anisotropy in this system are responsible for large thermal fluctuations and the presence of a liquid vortex phase in this low-temperature superconductor with a critical temperature of 11 K, consistent with the interpretation of the electrical transport data. The superconducting parametersmore » obtained from {lambda} and coherence length {zeta} place this compound in the extreme type II regime. Meissner responses (via MFM) at different locations across the sample are similar to each other, indicating good homogeneity of the superconducting state on a submicron scale.« less

Characteristics of a Strongly-Pulsed Non-Premixed Jet Flame in Cross-flow

NASA Astrophysics Data System (ADS)

Gamba, Mirko; Clemens, Noel T.; Ezekoye, Ofodike A.

2006-11-01

The effects of large-amplitude, high-frequency harmonic forcing of turbulent nonpremixed hydrogen/methane jet flames in cross-flow (JFICF) are investigated experimentally. Flame lengths, penetration lengths, and mixing characteristics are studied using flame luminosity imaging, planar laser Mie scattering visualization and particle image velocimetry. Mean jet Reynolds numbers of 1,600 and 3,250 (peak Re ˜2,500--6,500) with corresponding mean momentum flux ratios, r, of 1.9 and 3.7 (peak r ˜2.6--8.3) are considered. Forcing frequencies of 100 Hz and 300 Hz with amplitudes of ˜60%--300% are investigated. Consistent with previous work, a drastic decrease in flame length and soot emission, an increase in flame penetration and an improved jet fuel/cross-flow air mixing are observed for the larger forcing amplitude cases. Partial pre-mixing induced by near-field reverse flow, near-field vortex/vortex interaction and large-scale stirring, rendered stronger by large forcing amplitudes and frequencies, are thought to play a key role on the observed effects.

Solar activity as a possible cause of large forest fires--a case study: analysis of the Portuguese forest fires.

PubMed

Gomes, J F P; Radovanovic, M

2008-05-01

Fires of large dimension destroy forests, harvests and housing objects. Apart from that combustion products and burned surfaces become large ecological problems. Very often fires emerge simultaneously on different locations of a region so a question could be asked if they always have been a consequence of negligence, pyromania, high temperatures or maybe there has been some other cause. This paper is an attempt of establishing the possible connection between forest fires that numerous satellites registered and activities happening on the Sun immediately before fires ignite. Fires emerged on relatively large areas from Portugal and Spain on August 2005, as well as on other regions of Europe. The cases that have been analyzed show that, in every concrete situation, an emission of strong electromagnetic and thermal corpuscular energy from highly energetic regions that were in geo-effective position had preceded the fires. Such emissions have, usually, very high energy and high speeds of particles and come from coronary holes that also have been either in the very structure or in the immediate closeness of the geo-effective position. It should also be noted that the solar wind directed towards the Earth becomes weaker with deeper penetration towards the topographic surface. However, the results presented in this paper suggest that, there is a strong causality relationship between solar activity and the ignition of these forest fires taking place in South-western Europe.

Hawaii Energy Sustainable Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rocheleau, Richard; Turn, Scott; Griffin, James

The objective of HESP was to support the development and deployment of distributed energy resource (DER) technologies to facilitate increased penetration of renewable energy resources and reduced use of fossil fuels in Hawaii’s power grids. All deliverables, publications and other public releases have been submitted to the DOE in accordance with the award and subsequent award modifications.

Winter litter disturbance facilitates the spread of the nonnative invasive grass Microstegium vimineum (Trin.) A. Camus

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2007-01-01

We investigated the impacts of winter litter disturbance on the spread of the nonnative invasive plant Microstegium vimineum (Trin.) A. Camus through experimental removals. We hypothesized that light penetration through the litter layer facilitates the spread of M. vimineum in forested systems. Our objective, therefore, was to...

Electron percolation in realistic models of carbon nanotube networks

NASA Astrophysics Data System (ADS)

Simoneau, Louis-Philippe; Villeneuve, Jérémie; Rochefort, Alain

2015-09-01

The influence of penetrable and curved carbon nanotubes (CNT) on the charge percolation in three-dimensional disordered CNT networks have been studied with Monte-Carlo simulations. By considering carbon nanotubes as solid objects but where the overlap between their electron cloud can be controlled, we observed that the structural characteristics of networks containing lower aspect ratio CNT are highly sensitive to the degree of penetration between crossed nanotubes. Following our efficient strategy to displace CNT to different positions to create more realistic statistical models, we conclude that the connectivity between objects increases with the hard-core/soft-shell radii ratio. In contrast, the presence of curved CNT in the random networks leads to an increasing percolation threshold and to a decreasing electrical conductivity at saturation. The waviness of CNT decreases the effective distance between the nanotube extremities, hence reducing their connectivity and degrading their electrical properties. We present the results of our simulation in terms of thickness of the CNT network from which simple structural parameters such as the volume fraction or the carbon nanotube density can be accurately evaluated with our more realistic models.

A method for modeling contact dynamics for automated capture mechanisms

NASA Technical Reports Server (NTRS)

Williams, Philip J.

1991-01-01

Logicon Control Dynamics develops contact dynamics models for space-based docking and berthing vehicles. The models compute contact forces for the physical contact between mating capture mechanism surfaces. Realistic simulation requires proportionality constants, for calculating contact forces, to approximate surface stiffness of contacting bodies. Proportionality for rigid metallic bodies becomes quite large. Small penetrations of surface boundaries can produce large contact forces.

The value-based medicine comparative effectiveness and cost-effectiveness of penetrating keratoplasty for keratoconus.

PubMed

Roe, Richard H; Lass, Jonathan H; Brown, Gary C; Brown, Melissa M

2008-10-01

To perform a base case, comparative effectiveness, and cost-effectiveness (cost-utility) analysis of penetrating keratoplasty for patients with severe keratoconus. Visual acuity data were obtained from a large, retrospective multicenter study in which patients with keratoconus with less than 20/40 best corrected visual acuity and/or the inability to wear contact lenses underwent penetrating keratoplasty, with an average follow-up of 2.1 years. The results were combined with other retrospective studies investigating complication rates of penetrating keratoplasty. The data were then incorporated into a cost-utility model using patient preference-based, time trade-off utilities, computer-based decision analysis, and a net present value model to account for the time value of outcomes and money. The comparative effectiveness of the intervention is expressed in quality-of-life gain and QALYs (quality-adjusted life-years), and the cost-effectiveness results are expressed in the outcome of $/QALY (dollars spent per QALY). Penetrating keratoplasty in 1 eye for patients with severe keratoconus results in a comparative effectiveness (value gain) of 16.5% improvement in quality of life every day over the 44-year life expectancy of the average patient with severe keratoconus. Discounting the total value gain of 5.36 QALYs at a 3% annual discount rate yields 3.05 QALYs gained. The incremental cost for penetrating keratoplasty, including all complications, is $5934 ($5913 discounted at 3% per year). Thus, the incremental cost-utility (discounted at 3% annually) for this intervention is $5913/3.05 QALYs = $1942/QALY. If both eyes undergo corneal transplant, the total discounted value gain is 30% and the overall cost-utility is $2003. Surgery on the second eye confers a total discounted value gain of 2.5 QALYs, yielding a quality-of-life gain of 11.6% and a discounted cost-utility of $2238/QALY. Penetrating keratoplasty for patients with severe keratoconus seems to be a comparatively effective and cost-effective procedure when compared with other interventions across different medical specialties.

A comparative evaluation of the in vitro penetration performance of the improved Crest complete toothbrush versus the Current Crest complete toothbrush, the Colgate Precision toothbrush and the Oral-B P40 toothbrush.

PubMed

Volpenhein, D W; Handel, S E; Hughes, T J; Wild, J

1996-01-01

Removal of plaque and debris from interproximal surfaces during toothbrushing has generally been difficult to achieve, in large part because traditional flat-bristled toothbrushes do not offer good interproximal penetration. As a result, a number of varying bristle designs have been developed, with the rippled-design brush shown to be particularly effective at removing interproximal plaque. Recently, an existing brush, the original Crest Complete, was modified to offer a more deeply rippled version. This study evaluated the interproximal penetration of four bristle designs: rippled pattern (original Crest Complete), deeper rippled pattern (improved Crest Complete), multi-level (Colgate Precision), and flat-tufted (Oral-B P40). The study used a previously reported in vitro model for determining interproximal penetration of manual toothbrushes (J Clin Dent 5:27-33, 1994). In order to effectively mimic the in-use characteristics of toothbrushing, this model is based on analysis of videotaped consumer brushing habits, tooth morphology, and in vivo plaque tenacity characteristics and uses the three most predominantly used brushing techniques (circular, up-and-down, and back-and-forth, with the brush held at both 45 and 90 degrees to the tooth surface). In addition, the model's brush stroke length, brush force, and brush speed are likewise based on analysis of consumer brushing patterns. The results of the study indicate that the new Crest Complete with deeper rippled bristles provided significantly superior (p < or = 0.05) interproximal penetration than the Colgate Precision and Oral-B brushes overall and for three of the four brush strokes tested. In addition, the new Crest Complete was found to provide significantly superior interproximal penetration to the original Crest Complete overall and in circular and up-and-down strokes, and the original Crest Complete provided superior overall interproximal penetration to the Colgate and Oral-B brushes.

Cryopreservation and ensuing in vitro fertilization ability of boar spermatozoa from epididymides stored at 4 degrees C.

PubMed

Kikuchi, K; Nagai, T; Kashiwazaki, N; Ikeda, H; Noguchi, J; Shimada, A; Soloy, E; Kaneko, H

1998-09-01

The influence of prolonged storage of boar epididymides on post-thaw sperm motility, and in vitro fertilization was evaluated. Twenty pairs of epididymides were obtained from Large White boars, and spermatozoa from one of each of the pairs were immediately collected and frozen (control group). The remaining epididymides were cooled to 4 degrees C and stored for 1, 2 or 3 d, after which spermatozoa were collected and frozen (experimental groups Day 1, 2 and 3, respectively). Sperm motility was maintained throughout the dilution procedure and then dropped (P < 0.01) after freezing and thawing. During storage the motility of nonfrozen spermatozoa decreased significantly (P < 0.01), reaching a value equal to that of frozen-thawed spermatozoa on Day 3. In vitro fertilization experiments revealed significantly (P < 0.05) lower penetration rates using Day 1, 2 and 3 stored spermatozoa (12, 13 and 2%, respectively) than that of the control group (40%). Oocyte penetration ability seemed to be reflected by acrosome integrity. However, the motility of spermatozoa with the ability to penetrate oocytes in Day 1 and Day 2 groups did not differ from that of the controls. The motility of spermatozoa lacking penetration ability, on the other hand, gradually decreased as the storage period was prolonged. This suggests that the sperm motility and penetration ability are affected by different mechanisms during the cold storage of epididymides. Finally, control and experimental groups exhibited high incidences of monospermic penetration (64 to 90%) and of male pronuclear formation (67 to 71%). These data suggest that cryopreservation of spermatozoa from boar epididymides stored at 4 degrees C for 1 to 2 d can be used for conserving male germ cells when epididymal spermatozoa can not be collected immediately and cryopreserved.

The Epidemiology of and Outcome from Pancreatoduodenal Trauma in the UK, 1989–2013

PubMed Central

Bouamra, O; Kausar, A; Dickson, EJ; Lecky, F

2015-01-01

Introduction Pancreatoduodenal (PD) injury is an uncommon but serious complication of blunt and penetrating trauma, associated with high mortality. The aim of this study was to assess the incidence, mechanisms of injury, initial operation rates and outcome of patients who sustained PD trauma in the UK from a large trauma registry, over the period 1989–2013. Methods The Trauma Audit and Research Network database was searched for details of any patient with blunt or penetrating trauma to the pancreas, duodenum or both. Results Of 356,534 trauma cases, 1,155 (0.32%) sustained PD trauma. The median patient age was 27 years for blunt trauma and 27.5 years for penetrating trauma. The male-to-female ratio was 2.5:1. Blunt trauma was the most common type of injury seen, with a ratio of blunt-to-penetrating PD injury ratio of 3.6:1. Road traffic collision was the most common mechanism of injury, accounting for 673 cases (58.3%). The median injury severity score (ISS) was 25 (IQR: 14–35) for blunt trauma and 14 (IQR: 9–18) for penetrating trauma. The mortality rate for blunt PD trauma was 17.6%; it was 12.2% for penetrating PD trauma. Variables predicting mortality after pancreatic trauma were increasing age, ISS, haemodynamic compromise and not having undergone an operation. Conclusions Isolated pancreatic injuries are uncommon; most coexist with other injuries. In the UK, a high proportion of cases are due to blunt trauma, which differs from US and South African series. Mortality is high in the UK but comparison with other surgical series is difficult because of selection bias in their datasets. PMID:25723689

Unstable cervical spine fracture after penetrating neck injury: a rare entity in an analysis of 1,069 patients.

PubMed

Lustenberger, Thomas; Talving, Peep; Lam, Lydia; Kobayashi, Leslie; Inaba, Kenji; Plurad, David; Branco, Bernardino C; Demetriades, Demetrios

2011-04-01

The value of cervical spine immobilization after penetrating trauma to the neck is the subject of lively debate. The purpose of this study was to review the epidemiology of unstable cervical spine injuries (CSI) after penetrating neck trauma in a large cohort of patients. This is a retrospective analysis of patients admitted with penetrating neck injuries to a Level I trauma center from January 1996 through December 2008. A penetrating neck injury was defined as a gunshot wound (GSW) or stab wound (SW) between the clavicles and the base of the skull. Univariate and multivariate analyses were performed to investigate associations between injury mechanisms, the presence of CSI instability, and mortality. Risk factors independently associated with the presence of a CSI were identified. A total of 1,069 patients met inclusion criteria, of which 463 patients (43.3%) and 606 patients (56.7%) were sustaining GSW and SW, respectively. Overall, 65 patients (6.1%) were diagnosed with a CSI with a significantly higher incidence after GSWs compared with SWs (12.1% vs. 1.5%; p < 0.001). In four patients (0.4%), the CSI was considered unstable, all of them following GSW. All patients with unstable CSI had obvious neurologic deficits or altered mental status at the time of admission. Risk factors independently associated with the presence of a CSI were GSW to the neck and a Glasgow Coma Scale score ≤8 on admission (R = 0.16). The overall incidence of unstable CSI after penetrating trauma to the neck is exceedingly low at 0.4%. Following GSW to the neck, an unstable CSI was noted in <1% of patients. After cervical SW, however, no spinal instability was noted precluding the need for spinal precautions in these instances.

The Dutch founder mutation SDHD.D92Y shows a reduced penetrance for the development of paragangliomas in a large multigenerational family.

PubMed

Hensen, Erik F; Jansen, Jeroen C; Siemers, Maaike D; Oosterwijk, Jan C; Vriends, Annette Hjt; Corssmit, Eleonora Pm; Bayley, Jean-Pierre; van der Mey, Andel Gl; Cornelisse, Cees J; Devilee, Peter

2010-01-01

Germline mutations in SDHD predispose to the development of head and neck paragangliomas, and phaeochromocytomas. The risk of developing a tumor depends on the sex of the parent who transmits the mutation: paragangliomas only arise upon paternal transmission. In this study, both the risk of paraganglioma and phaeochromocytoma formation, and the risk of developing associated symptoms were investigated in 243 family members with the SDHD.D92Y founder mutation. By using the Kaplan-Meier method, age-specific penetrance was calculated separately for paraganglioma formation as defined by magnetic resonance imaging (MRI) and for paraganglioma-related signs and symptoms. Evaluating clinical signs and symptoms alone, the penetrance reached a maximum of 57% by the age of 47 years. When MRI detection of occult paragangliomas was included, penetrance was estimated to be 54% by the age of 40 years, 68% by the age of 60 years and 87% by the age of 70 years. Multiple tumors were found in 65% and phaeochromocytomas were diagnosed in 8% of paraganglioma patients. Malignant paraganglioma was diagnosed in one patient (3%). Although the majority of carriers of a paternally inherited SDHD mutation will eventually develop head and neck paragangliomas, we find a lower penetrance than previous estimates from studies based on predominantly index cases. The family-based study described here emphasizes the importance of the identification and inclusion of clinically unaffected mutation carriers in all estimates of penetrance. This finding will allow a more accurate genetic counseling and warrants a 'wait and scan' policy for asymptomatic paragangliomas, combined with biochemical screening for catecholamine excess in SDHD-linked patients.

The epidemiology of and outcome from pancreatoduodenal trauma in the UK, 1989-2013.

PubMed

O'Reilly, D A; Bouamra, O; Kausar, A; Malde, D J; Dickson, E J; Lecky, F

2015-03-01

Pancreatoduodenal (PD) injury is an uncommon but serious complication of blunt and penetrating trauma, associated with high mortality. The aim of this study was to assess the incidence, mechanisms of injury, initial operation rates and outcome of patients who sustained PD trauma in the UK from a large trauma registry, over the period 1989-2013. The Trauma Audit and Research Network database was searched for details of any patient with blunt or penetrating trauma to the pancreas, duodenum or both. Of 356,534 trauma cases, 1,155 (0.32%) sustained PD trauma. The median patient age was 27 years for blunt trauma and 27.5 years for penetrating trauma. The male-to-female ratio was 2.5:1. Blunt trauma was the most common type of injury seen, with a ratio of blunt-to-penetrating PD injury ratio of 3.6:1. Road traffic collision was the most common mechanism of injury, accounting for 673 cases (58.3%). The median injury severity score (ISS) was 25 (IQR: 14-35) for blunt trauma and 14 (IQR: 9-18) for penetrating trauma. The mortality rate for blunt PD trauma was 17.6%; it was 12.2% for penetrating PD trauma. Variables predicting mortality after pancreatic trauma were increasing age, ISS, haemodynamic compromise and not having undergone an operation. Isolated pancreatic injuries are uncommon; most coexist with other injuries. In the UK, a high proportion of cases are due to blunt trauma, which differs from US and South African series. Mortality is high in the UK but comparison with other surgical series is difficult because of selection bias in their datasets.

Medicaid HMO Penetration and Its Mix: Did Increased Penetration Affect Physician Participation in Urban Markets?

PubMed Central

Adams, E Kathleen; Herring, Bradley

2008-01-01

Objective To use changes in Medicaid health maintenance organization (HMO) penetration across markets over time to test for effects on the extent of Medicaid participation among physicians and to test for differences in the effects of increased use of commercial versus Medicaid-dominant plans within the market. Data Sources/Study Setting The nationally representative Community Tracking Study's Physician Survey for three periods (1996–1997, 1998–1999, and 2000–2001) on 29,866 physicians combined with Centers for Medicare and Medicaid Services (CMS) and InterStudy data. Study Design Market-level estimates of Medicaid HMO penetration are used to test for (1) any participation in Medicaid and (2) the degree to which physicians have an “open” (i.e., nonlimited) practice accepting new Medicaid patients. Models account for physician, firm, and local characteristics, Medicaid relative payment levels adjusted for geographic variation in practice costs, and market-level fixed effects. Principal Findings There is a positive effect of increases in commercial Medicaid HMO penetration on the odds of accepting new Medicaid patients among all physicians, and in particular, among office-based physicians. In contrast, there is no effect, positive or negative, from expanding the penetration of Medicaid-dominant HMO plans within the market. Increases in cost-adjusted Medicaid fees, relative to Medicare levels, were associated with increases in the odds of participation and of physicians having an “open” Medicaid practice. Provider characteristics that consistently lower participation among all physicians include being older, board certified, a U.S. graduate and a solo practitioner. Conclusions The effects of Medicaid HMO penetration on physician participation vary by the type of plan. If states are able to attract and retain commercial plans, participation by office-based physicians is likely to increase in a way that opens existing practices to more new Medicaid patients. Other policy variables that affect participation include the presence of a federally qualified health center (FQHC) in the county and cost-adjusted Medicaid fees relative to Medicare. PMID:18199191

Performance characteristics of a conformal ultra-wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non-resectable tumours.

PubMed

Smrkovski, O A; Koo, Y; Kazemi, R; Lembcke, L M; Fathy, A; Liu, Q; Phillips, J C

2013-03-01

Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth of 4.59 cm compared to 2.74 cm for the flat antenna. Clinical use of the antenna was then evaluated in six animals with locoregionally advanced solid tumours receiving adjuvant chemotherapy. During clinical applications, therapeutic temperatures were achieved at depths ≥4 cm. Objective responses were seen in all patients; tissue toxicity in one case limited further therapy. This antenna provides compact, efficient, focused and deep-penetrating clinical hyperthermia for the treatment of solid tumours in veterinary patients. © 2011 Blackwell Publishing Ltd.

On the thickness of accretion curtains on magnetized compact objects from analysis of their fast aperiodic time variability.

NASA Astrophysics Data System (ADS)

Semena, Andrey

It is widely accepted that accretion onto magnetized compact objects is channelled to some areas close to magnetic poles of the star. Thickness of this channelled accretion flow intimately depends on details of penetration of highly conducting plasma of the flow to the compact object magnetosphere, i.e. on magnetic diffusivity etc. Until now our knowledge of these plasma properties is scarce. In our work we present our attempts to estimate the thickness of the plasma flow on top of the magnetosphere from observations of accreting intermediate polars (magnetized white dwarfs). We show that properties of aperiodic noise of accreting intermediate polars can be used to put constrains on cooling time of hot plasma, heated in the standing shock wave above the WD surface. Estimates of the cooling time and the mass accretion rate provide us a tool to measure the density of post-shock plasma and the cross-sectional area of the accretion funnel at the WD surface. We have studied aperiodic noise of emission of one of the brightest intermediate polar EX Hya with the help of data in optical and X-ray energy bands. We put an upper limit on the plasma cooling timescale tau <0.2-0.5 sec, on the fractional area of the accretion curtain footprint f < 1.6 × 10(-4) . We show that measurements of accretion column footprints, combined with results of the eclipse mapping, can be used to obtain an upper limit on the penetration depth of the accretion disc plasma at the boundary of the magnetosphere, Delta r / r ≈ 10(-3) If the magnetospheres of accreting neutron stars have similar plasma penetration depths at their boundaries, we predict that footprints of their accretion columns should be very small, with fractional areas < 10(-6) .

Lack of dependence on resonant error field of locked mode island size in ohmic plasmas in DIII-D

DOE PAGES

Haye, R. J. La; Paz-Soldan, C.; Strait, E. J.

2015-01-23

DIII-D experiments show that fully penetrated resonant n=1 error field locked modes in Ohmic plasmas with safety factor q 95≳3 grow to similar large disruptive size, independent of resonant error field correction. Relatively small resonant (m/n=2/1) static error fields are shielded in Ohmic plasmas by the natural rotation at the electron diamagnetic drift frequency. However, the drag from error fields can lower rotation such that a bifurcation results, from nearly complete shielding to full penetration, i.e., to a driven locked mode island that can induce disruption.

Solar space heating system at the Seeley G. Mudd Education Building, Pacific School of Religion, 1798 Scenic Avenue, Berkeley California 94708. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Large areas of south facing glass allow winter sunlight to penetrate the building, while overhangs provide summer shading. High ceilings allow deep penetration of this light for space heating and natural lighting. Massive construction stores solar radiation for evening warmth and provides a buffer from extreme temperature fluctuations. Natural ventilation will provide cooling. The system consists of 720 square feet of roof-mounted, liquid, flat plate solar collectors and three 350 gallon fiberglass storage tanks. The acceptance and performance tests are discussed. Also discusseed are: collector selection, construction contract, costs, and economics.

Globulettes as Seeds of Brown Dwarfs and Free-Floating Planetary-Mass Objects

NASA Astrophysics Data System (ADS)

Gahm, G. F.; Grenman, T.; Fredriksson, S.; Kristen, H.

2007-04-01

Some H II regions surrounding young stellar clusters contain tiny dusty clouds, which on photos look like dark spots or teardrops against a background of nebular emission. From our collection of Hα images of 10 H II regions gathered at the Nordic Optical Telescope, we found 173 such clouds, which we call "globulettes," since they are much smaller than normal globules and form a distinct class of objects. Many globulettes are quite isolated and located far from the molecular shells and elephant trunks associated with the regions. Others are attached to the trunks (or shells), suggesting that globulettes may form as a consequence of erosion of these larger structures. None of our objects appear to contain stellar objects. The globulettes were measured for position, dimension, and orientation, and we find that most objects are smaller than 10 kAU. The Rosette Nebula and IC 1805 are particularly rich in globulettes, for which the size distributions peak at mean radii of ~2.5 kAU, similar to what was found by Reipurth and coworkers and De Marco and coworkers for similar objects in other regions. We estimate total mass and density distributions for each object from extinction measures and conclude that a majority contain <13 MJ, corresponding to planetary-mass objects. We then estimate the internal thermal and potential energies and find, when also including the effects from the outer pressure, that a large fraction of the globulettes could be unstable and would contract on short timescales, <10 6 yr. In addition, the radiation pressure and ram pressure exerted on the side facing the clusters would stimulate contraction. Since the globulettes are not screened from stellar light by dust clouds farther in, one would expect photoevaporation to dissolve the objects. However, surprisingly few objects show bright rims or teardrop forms. We calculate the expected lifetimes against photoevaporation. These lifetimes scatter around 4 × 106 yr, much longer than estimated in previous studies and also much longer than the free-fall time. We conclude that a large number of our globulettes have time to form central low-mass objects long before the ionization front, driven by the impinging Lyman photons, has penetrated far into the globulette. Hence, the globulettes may be one source in the formation of brown dwarfs and free-floating planetary-mass objects in the galaxy. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.

Muco-inert nanoparticle probes and drug carriers

NASA Astrophysics Data System (ADS)

Wang, Ying-Ying

2011-12-01

Mucus coats the exposed surfaces of the eyes and respiratory, gastrointestinal (GI) and cervicovaginal (CV) tracts, and protects mucosal tissues against pathogens and other foreign particulates. Most foreign particles are effectively trapped in mucus through steric and adhesive interactions, and are rapidly eliminated by different mucus clearance mechanisms. Nevertheless, mucus also immobilizes conventional drug and gene carriers, thereby precluding sustained and targeted drug delivery to mucosal sites. Synthetic particles engineered with muco-inert surfaces, and some viruses, can readily penetrate mucus gel, and may serve as useful probes to understand the biophysical barrier properties of mucus. Improved understanding of the mucus barrier could provide insights into methods to enhance drug and gene delivery at mucosal surfaces, as well as understanding the occasional failure of mucus to protect against infection or injury. Recently, muco-inert nanoparticles were developed by conjugating a dense layer of low MW polyethylene glycol to particle surfaces. Since they are slowed only by steric obstruction from the mucus mesh, various sized muco-inert nanoparticles can be used to probe the microstructure and microrheology of mucus. I applied this technique to determine whether the mucus barrier may be altered by exogenous factors, including the presence of detergent, pH changes and synthetic nanoparticles. I first studied the microrheology of native human cervicovaginal mucus (CVM), and found that CVM behaves as a viscoelastic solid at length scales ≥ 1 microm (preventing large particles from diffusing through) but as a viscoelastic liquid at length scales up to at least 500 nm (allowing smaller particles to diffuse through low viscosity fluid-filled pores). Treating CVM with a nonionic detergent, N9, shifted the viscoelastic liquid-solid transition point to < 200 nm, suggesting hydrophobic interactions between mucin fibers play an important role in regulating the mucus microstructure and consequently the microrheology. Indeed, N9 caused the average mucus pore size to decrease from ˜340 nm to 130 nm. I then looked at the effect of pH on mucus and found that the microstructure of CVM is essentially pH-independent over a broad range of physiological pH. Between pH 4 (the native pH of CVM) and 6--7, the average pore size in the mucus mesh remained unchanged, and between pH 1--2 and 8--9, there was at most a 2-fold drop in the average pore size (likely due to changes in electrostatic vs. hydrophobic interactions between mucin fibers). Finally, I found that mucoadhesive synthetic nanoparticles, at sufficiently high concentrations, can bundle mucin fibers and create large openings in the mucus microstructure. Disruption of the mucus barrier in this manner allowed a greater fraction of large (1 microm) muco-inert particles to diffuse through the mucus mesh. Muco-inert nanoparticles---also referred to as "mucus-penetrating particles" (MPP)---offer the potential for sustained and targeted drug delivery to mucosal surfaces. By penetrating luminal mucus layers, MPP may be able to reach the slowly cleared adherent mucus layer or deep folds of the epithelium and thereby achieve prolonged retention. I first measured the long range penetration of MPP compared to conventional mucoadhesive particles (CP) into CVM. With minimal dilution of CVM, MPP could penetrate up to 200 microm over 1 hr with ˜530 particles/mm2 penetrating 100 microm or more, while CP remained immobilized (note that physiological mucus layer thicknesses are no more than ˜200 microm). Furthermore, with 30% v/v dilution, MPP could penetrate up to 1.5 mm over 1 hr with ˜74,000 particles/mm2 penetrating 100 microm or more, while CP continued to remain stuck. I then studied the distribution and retention of MPP vs. CP in the mouse vagina to determine whether improved mucus penetration leads to more uniform distribution and prolonged retention. I found that MPP were not only more uniformly distributed in the vaginal lumen, but also penetrated deep into epithelial folds. In contrast, CP were aggregated by luminal mucus and failed to reach the epithelium. Several-fold more MPP were retained on the vaginal epithelial surface than CP over at least ˜1 day. Drug and gene carriers that provide more uniform and longer-lasting coverage of mucosal surfaces may greatly improve the treatment or prevention of diseases at mucosal sites.

Maturational changes in motility, acrosomal proteolytic activity, and penetrability of the inner perivitelline layer of fowl sperm, during their passage through the male genital tract.

PubMed

Ahammad, Muslah U; Nishino, C; Tatemoto, H; Okura, N; Kawamoto, Y; Okamoto, S; Nakada, T

2011-10-01

The objective was to examine, in vitro, the motility, acrosomal proteolytic activity (APA), and penetrating ability of fowl sperm recovered from the testis and epididymis, as well as the proximal, middle, and distal vas deferens, to assess the potential fertilizing ability of sperm as a function of maturation. A motile sperm separation technique was used to estimate sperm motility with Accudenz, a gelatin slide technique was used to measure the diameter of the halo around the acrosome of individual sperm as an indication of APA, and a sperm-inner perivitelline layer (IPL) interaction assay was done to estimate the number of hole formations as an indication of sperm penetration into the IPL. Sperm in the testis exhibited the least motility, produced the smallest halos, and created the least number of holes per 0.25 mm(2). Motility, diameter of the halo, and number of holes increased gradually (P < 0.05) from the epididymis to the distal vas deferens and were markedly different (P < 0.05) between testicular and deferent duct sperm. Based on these in vitro experimental findings, we inferred that fowl sperm undergo a gradual process of maturational changes in motility, APA, and penetrability as a means of acquiring potential fertility during their passage throughout the male genital tract. Copyright © 2011 Elsevier Inc. All rights reserved.

Reduced adherence of Candida to silane-treated silicone rubber.

PubMed

Price, C L; Williams, D W; Waters, M G J; Coulthwaite, L; Verran, J; Taylor, R L; Stickler, D; Lewis, M A O

2005-07-01

Silicone rubber is widely used in the construction of medical devices that can provide an essential role in the treatment of human illness. However, subsequent microbial colonization of silicone rubber can result in clinical infection or device failure. The objective of this study was to determine the effectiveness of a novel silane-treated silicone rubber in inhibiting microbial adherence and material penetration. Test material was prepared by a combination of argon plasma discharge treatment and fluorinated silane coupling. Chemicophysical changes were then confirmed by X-ray photoelectron spectroscopy, contact-angle measurement, and atomic force microscopy. Two separate adherence assays and a material penetration assay assessed the performance of the new material against four strains of Candida species. Results showed a significant reduction (p < 0.01) of Candida albicans GDH 2346 adherence to silane-treated silicone compared with untreated controls. This reduction was still evident after the incorporation of saliva into the assay. Adherence inhibition also occurred with Candida tropicalis MMU and Candida krusei NCYC, although this was assay dependent. Reduced penetration of silane-treated silicone by Candida was evident when compared to untreated controls, plaster-processed silicone, and acrylic-processed silicone. To summarize, a novel silicone rubber material is described that inhibits both candidal adherence and material penetration. The clinical benefit and performance of this material remains to be determined. Copyright 2005 Wiley Periodicals, Inc.

Enantioselective penetration enhancing effect of carvone on the in vitro transdermal permeation of nicorandil.

PubMed

Krishnaiah, Yellela S R; Nada, Aly

2012-01-01

The objective was to investigate the difference in penetration enhancing effect of R-carvone, S-carvone and RS-carvone on the in vitro transdermal drug permeation. In vitro permeation studies were carried out across neonatal rat epidermis from 2%w/v HPMC (hydroxypropyl methylcellulose) gel containing 4%w/v of nicorandil (a model drug) and a selected concentration (12%w/v) of either R-carvone, S-carvone or RS-carvone against a control. The stratum corneum (SC) of rats was treated with vehicle (70%v/v ethanol-water) or ethanolic solutions of 12%w/v R-carvone, S-carvone or RS-carvone. The enhancement ratio (ER) of R-carvone, S-carvone and RS-carvone when compared to control was about 37.1, 31.2 and 29.9, respectively indicating enantioselective penetration enhancing effect of carvone enantiomers. Furthermore, there was a significant decrease in the lag time required to produce a steady-state flux of nicorandil with S-carvone when compared to R-carvone and RS-carvone. DSC and FT-IR studies indicate that the investigated enantiomers of carvone exhibit a difference in their ability to affect the cellular organization of SC lipids and proteins thereby showing enantioselective transdermal drug permeation. It was concluded that R-carvone exhibited a higher penetration enhancing activity on transdermal permeation of nicorandil when compared to its S-isomer or racemic mixture.

Microgrid optimal scheduling considering impact of high penetration wind generation

NASA Astrophysics Data System (ADS)

Alanazi, Abdulaziz

The objective of this thesis is to study the impact of high penetration wind energy in economic and reliable operation of microgrids. Wind power is variable, i.e., constantly changing, and nondispatchable, i.e., cannot be controlled by the microgrid controller. Thus an accurate forecasting of wind power is an essential task in order to study its impacts in microgrid operation. Two commonly used forecasting methods including Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Network (ANN) have been used in this thesis to improve the wind power forecasting. The forecasting error is calculated using a Mean Absolute Percentage Error (MAPE) and is improved using the ANN. The wind forecast is further used in the microgrid optimal scheduling problem. The microgrid optimal scheduling is performed by developing a viable model for security-constrained unit commitment (SCUC) based on mixed-integer linear programing (MILP) method. The proposed SCUC is solved for various wind penetration levels and the relationship between the total cost and the wind power penetration is found. In order to reduce microgrid power transfer fluctuations, an additional constraint is proposed and added to the SCUC formulation. The new constraint would control the time-based fluctuations. The impact of the constraint on microgrid SCUC results is tested and validated with numerical analysis. Finally, the applicability of proposed models is demonstrated through numerical simulations.

HMO market penetration and hospital cost inflation in California.

PubMed

Robinson, J C

1991-11-20

OBJECTIVE--Health maintenance organizations (HMOs) have stimulated price competition in California hospital markets since 1983, when the state legislature eliminated barriers to selective contracting by conventional health insurance plans. This study measures the impact of HMO-induced price competition on the rate of inflation in average cost per admission for 298 private, non-HMO hospitals between 1982 and 1988. DATA--HMO market penetration was calculated using discharge abstract data on insurance coverage, ZIP code of residence, and hospital of choice for 3.35 million patients in 1983 and 3.41 million patients in 1988. Data on hospital characteristics were obtained from the American Hospital Association and other sources. -HMO coverage grew from an average of 8.3% of all admissions in local hospital markets in 1983 to 17.0% of all admissions in 1988. The average rate of growth in costs per admission between 1982 and 1988 was 9.4% lower in markets with relatively high HMO penetration compared with markets with relatively low HMO penetration (95% confidence interval, 5.2 to 13.8). Cost savings for these 298 hospitals are estimated at $1.04 billion for 1988. CONCLUSION--Price competition between HMOs and conventional health insurers can significantly reduce hospital cost inflation if legislative barriers to selective contracting are removed. The impact of competition in California was modest, however, when evaluated in terms of the 74.5% average rate of California hospital cost inflation during these years.

[In vitro transdermal delivery of the active fraction of xiangfusiwu decoction based on principal component analysis].

PubMed

Li, Zhen-Hao; Liu, Pei; Qian, Da-Wei; Li, Wei; Shang, Er-Xin; Duan, Jin-Ao

2013-06-01

The objective of the present study was to establish a method based on principal component analysis (PCA) for the study of transdermal delivery of multiple components in Chinese medicine, and to choose the best penetration enhancers for the active fraction of Xiangfusiwu decoction (BW) with this method. Improved Franz diffusion cells with isolated rat abdomen skins were carried out to experiment on the transdermal delivery of six active components, including ferulic acid, paeoniflorin, albiflorin, protopine, tetrahydropalmatine and tetrahydrocolumbamine. The concentrations of these components were determined by LC-MS/MS, then the total factor scores of the concentrations at different times were calculated using PCA and were employed instead of the concentrations to compute the cumulative amounts and steady fluxes, the latter of which were considered as the indexes for optimizing penetration enhancers. The results showed that compared to the control group, the steady fluxes of the other groups increased significantly and furthermore, 4% azone with 1% propylene glycol manifested the best effect. The six components could penetrate through skin well under the action of penetration enhancers. The method established in this study has been proved to be suitable for the study of transdermal delivery of multiple components, and it provided a scientific basis for preparation research of Xiangfusiwu decoction and moreover, it could be a reference for Chinese medicine research.

How sharp is sharp? Towards quantification of the sharpness and penetration ability of kitchen knives used in stabbings.

PubMed

Hainsworth, S V; Delaney, R J; Rutty, G N

2008-07-01

Stabbing is the most common method for violent death in the UK. As part of their investigation, forensic pathologists are commonly asked to estimate or quantify the degree of force required to create a wound. The force required to penetrate the skin and body by a knife is a complex function of the sharpness of the knife, the area of the body and alignment with cleavage lines of the skin, the angle of attack and the relative movement of the person stabbing relative to the victim being stabbed. This makes it difficult for the forensic pathologist to give an objective answer to the question; hence, subjective estimations are often used. One area where some degree of quantification is more tractable is in assessing how sharp an implement (particularly a knife) is. This paper presents results of a systematic study of how the different aspects of knife geometry influence sharpness and presents a simple test for assessing knife sharpness using drop testing. The results show that the radius of the blunt edge at the tip is important for controlling the penetration ability of a kitchen knife. Using high-speed video, it also gives insight into the mechanism of knife penetration into the skin. The results of the study will aid pathologists in giving a more informed answer to the question of the degree of force used in stabbing.

AIAA Survivability Technical Committee Draft

NASA Technical Reports Server (NTRS)

Shipman, Jim; Williamson, Joel

1997-01-01

A relatively new area of interest in aerospace systems survivability is the growing threat of spacecraft penetration by orbital debris. Orbital debris, or "space junk", is composed of the man-made remnants of non-functioning spacecraft still orbiting the Earth. NASA estimates that there are currently over 100,000 orbital debris particles 1 centimeter in diameter or larger that cannot be tracked by existing radar, with the population growing at approximately 4% per year in low earth orbits. With an average velocity of over 8.7 km/sec, these projectiles can penetrate and disable many vulnerable spacecraft systems. Since the likelihood of spacecraft penetration increases with spacecraft surface area, large spacecraft (such as the International Space Station) and communication satellite fleets (such as Iridium) have begun to adopt survivability enhancement strategies similar to those employed by combat aircraft. Collision avoidance maneuvers are commonly practiced by the Space Shuttle and are planned by the International Space Station to decrease their susceptibility to impact by trackable orbital debris; likewise, improved shielding, internal equipment placement, and improved crew operations following penetration can reduce the vulnerability of spacecraft to loss following orbital debris impact. Computer simulations such as the Manned Spacecraft and Crew Survivability (MSCSurv) program at the NASA-Marshall Space Flight Center have recently been developed to quantify and reduce the likelihood of crew or spacecraft loss following orbital debris penetration. The AIAA Survivability Technical Committee is working to enable the transfer of military-developed survivability technologies to help the aerospace industry cope with this growing threat.

DOE/NREL supported wind energy activities in Alaska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drouilhet, S.

1997-12-01

This paper describes three wind energy projects implemented in Alaska. The first, a sustainable technology energy partnerships (STEP) wind energy deployment project in Kotzebue will install 6 AOC 15/50 wind turbines and connect to the existing village diesel grid, consisting of approximately 1 MW average load. It seeks to develop solutions to the problems of arctic wind energy installations (transport, foundations, erection, operation, and maintenance), to establish a wind turbine test site, and to establish the Kotzebue Electric Association as a training and deployment center for wind/diesel technology in rural Alaska. The second project, a large village medium-penetration wind/diesel system,more » also in Kotzebue, will install a 1-2 MW windfarm, which will supplement the AOC turbines of the STEP project. The program will investigate the impact of medium penetration wind energy on power quality and system stability. The third project, the Alaska high-penetration wind/diesel village power pilot project in Wales will install a high penetration (80-100%) wind/diesel system in a remote Alaskan village. The system will include about 180 kW installed wind capacity, meeting an average village load of about 60 kW. This program will provide a model for high penetration wind retrofits to village diesel power systems and build the capability in Alaska to operate, maintain, and replicate wind/diesel technology. The program will also address problems of: effective use of excess wind energy; reliable diesel-off operation; and the role of energy storage.« less

Influence of control group on effect size in trials of acupuncture for chronic pain: a secondary analysis of an individual patient data meta-analysis.

PubMed

MacPherson, Hugh; Vertosick, Emily; Lewith, George; Linde, Klaus; Sherman, Karen J; Witt, Claudia M; Vickers, Andrew J

2014-01-01

In a recent individual patient data meta-analysis, acupuncture was found to be superior to both sham and non-sham controls in patients with chronic pain. In this paper we identify variations in types of sham and non-sham controls used and analyze their impact on the effect size of acupuncture. Based on literature searches of acupuncture trials involving patients with headache and migraine, osteoarthritis, and back, neck and shoulder pain, 29 trials met inclusion criteria, 20 involving sham controls (n = 5,230) and 18 non-sham controls (n = 14,597). For sham controls, we analysed non-needle sham, penetrating sham needles and non-penetrating sham needles. For non-sham controls, we analysed non-specified routine care and protocol-guided care. Using meta-regression we explored impact of choice of control on effect of acupuncture. Acupuncture was significantly superior to all categories of control group. For trials that used penetrating needles for sham control, acupuncture had smaller effect sizes than for trials with non-penetrating sham or sham control without needles. The difference in effect size was -0.45 (95% C.I. -0.78, -0.12; p = 0.007), or -0.19 (95% C.I. -0.39, 0.01; p = 0.058) after exclusion of outlying studies showing very large effects of acupuncture. In trials with non-sham controls, larger effect sizes associated with acupuncture vs. non-specified routine care than vs. protocol-guided care. Although the difference in effect size was large (0.26), it was not significant with a wide confidence interval (95% C.I. -0.05, 0.57, p = 0.1). Acupuncture is significantly superior to control irrespective of the subtype of control. While the choice of control should be driven by the study question, our findings can help inform study design in acupuncture, particularly with respect to sample size. Penetrating needles appear to have important physiologic activity. We recommend that this type of sham be avoided.

Estimation of scattering object characteristics for image reconstruction using a nonzero background.

PubMed

Jin, Jing; Astheimer, Jeffrey; Waag, Robert

2010-06-01

Two methods are described to estimate the boundary of a 2-D penetrable object and the average sound speed in the object. One method is for circular objects centered in the coordinate system of the scattering observation. This method uses an orthogonal function expansion for the scattering. The other method is for noncircular, essentially convex objects. This method uses cross correlation to obtain time differences that determine a family of parabolas whose envelope is the boundary of the object. A curve-fitting method and a phase-based method are described to estimate and correct the offset of an uncentered radial or elliptical object. A method based on the extinction theorem is described to estimate absorption in the object. The methods are applied to calculated scattering from a circular object with an offset and to measured scattering from an offset noncircular object. The results show that the estimated boundaries, sound speeds, and absorption slopes agree very well with independently measured or true values when the assumptions of the methods are reasonably satisfied.

Derivation of WECC Distributed PV System Model Parameters from Quasi-Static Time-Series Distribution System Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mather, Barry A; Boemer, Jens C.; Vittal, Eknath

The response of low voltage networks with high penetration of PV systems to transmission network faults will, in the future, determine the overall power system performance during certain hours of the year. The WECC distributed PV system model (PVD1) is designed to represent small-scale distribution-connected systems. Although default values are provided by WECC for the model parameters, tuning of those parameters seems to become important in order to accurately estimate the partial loss of distributed PV systems for bulk system studies. The objective of this paper is to describe a new methodology to determine the WECC distributed PV system (PVD1)more » model parameters and to derive parameter sets obtained for six distribution circuits of a Californian investor-owned utility with large amounts of distributed PV systems. The results indicate that the parameters for the partial loss of distributed PV systems may differ significantly from the default values provided by WECC.« less

Approach to explosive hazard detection using sensor fusion and multiple kernel learning with downward-looking GPR and EMI sensor data

NASA Astrophysics Data System (ADS)

Pinar, Anthony; Masarik, Matthew; Havens, Timothy C.; Burns, Joseph; Thelen, Brian; Becker, John

2015-05-01

This paper explores the effectiveness of an anomaly detection algorithm for downward-looking ground penetrating radar (GPR) and electromagnetic inductance (EMI) data. Threat detection with GPR is challenged by high responses to non-target/clutter objects, leading to a large number of false alarms (FAs), and since the responses of target and clutter signatures are so similar, classifier design is not trivial. We suggest a method based on a Run Packing (RP) algorithm to fuse GPR and EMI data into a composite confidence map to improve detection as measured by the area-under-ROC (NAUC) metric. We examine the value of a multiple kernel learning (MKL) support vector machine (SVM) classifier using image features such as histogram of oriented gradients (HOG), local binary patterns (LBP), and local statistics. Experimental results on government furnished data show that use of our proposed fusion and classification methods improves the NAUC when compared with the results from individual sensors and a single kernel SVM classifier.

Navigating a social world with robot partners: A quantitative cartography of the Uncanny Valley.

PubMed

Mathur, Maya B; Reichling, David B

2016-01-01

Android robots are entering human social life. However, human-robot interactions may be complicated by a hypothetical Uncanny Valley (UV) in which imperfect human-likeness provokes dislike. Previous investigations using unnaturally blended images reported inconsistent UV effects. We demonstrate an UV in subjects' explicit ratings of likability for a large, objectively chosen sample of 80 real-world robot faces and a complementary controlled set of edited faces. An "investment game" showed that the UV penetrated even more deeply to influence subjects' implicit decisions concerning robots' social trustworthiness, and that these fundamental social decisions depend on subtle cues of facial expression that are also used to judge humans. Preliminary evidence suggests category confusion may occur in the UV but does not mediate the likability effect. These findings suggest that while classic elements of human social psychology govern human-robot social interaction, robust UV effects pose a formidable android-specific problem. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Computational modeling of the nonlinear stochastic dynamics of horizontal drillstrings

NASA Astrophysics Data System (ADS)

Cunha, Americo; Soize, Christian; Sampaio, Rubens

2015-11-01

This work intends to analyze the nonlinear stochastic dynamics of drillstrings in horizontal configuration. For this purpose, it considers a beam theory, with effects of rotatory inertia and shear deformation, which is capable of reproducing the large displacements that the beam undergoes. The friction and shock effects, due to beam/borehole wall transversal impacts, as well as the force and torque induced by bit-rock interaction, are also considered in the model. Uncertainties of bit-rock interaction model are taken into account using a parametric probabilistic approach. Numerical simulations have shown that the mechanical system of interest has a very rich nonlinear stochastic dynamics, which generate phenomena such as bit-bounce, stick-slip, and transverse impacts. A study aiming to maximize the drilling process efficiency, varying drillstring velocities of translation and rotation is presented. Also, the work presents the definition and solution of two optimizations problems, one deterministic and one robust, where the objective is to maximize drillstring rate of penetration into the soil respecting its structural limits.

Cratering and penetration experiments in Teflon targets at velocities from 1 to 7 km/s

NASA Technical Reports Server (NTRS)

Hoerz, Friedrich; Bernhard, Ronald P.; Cintala, Mark J.; See, Thomas H.

1995-01-01

Approximately 20 sq m of protective thermal blankets, largely composed of Teflon, were retrieved from the Long Duration Exposure Facility (LDEF) after the spacecraft had spent approximately 5.7 years in space. Examination of these blankets revealed that they contained thousands of hypervelocity impact features ranging from micron-sized craters to penetration holes several millimeters in diameter. We conducted impact experiments in an effort to reproduce such features and to -- hopefully -- understand the relationships between projectile size and the resulting crater or penetration-hole diameter over a wide range of impact velocity. Such relationships are needed to derive the size- and mass-frequency distribution and flux of natural and man-made particles in low-Earth orbit. Powder propellant and light-gas guns were used to launch soda-lime glass spheres of 3.175 mm (1/8 inch) nominal diameter (Dp) into pure Teflon FEP targets at velocities ranging from 1 to 7 km/s. Target thickness (T) was varied over more than three orders of magnitude from infinite halfspace targets (Dp/T less than 0.1) to very thin films (Dp/T greater than 100). Cratering and penetration of massive Teflon targets is dominated by brittle failure and the development of extensive spall zones at the target's front and, if penetrated, the target's rear side. Mass removal by spallation at the back side of Teflon targets may be so severe that the absolute penetration-hole diameter (Dh) can become larger than that of a standard crater (Dc) at relative target thicknesses of Dp/T = 0.6-0.9. The crater diameter is infinite halfspace Teflon targets increases -- at otherwise constant impact conditions -- with encounter velocity by a factor of V0.44. In contrast, the penetration-hole size is very thin foils (Dp/T greater than 50) is essentially unaffected by impact velocity. Penetrations at target thicknesses intermediate to these extremes will scale with variable exponents of V. Our experimental matrix is sufficiently systematic and complete, up to 7 km/s, to make reasonable recommendations for the velocity-scaling of Teflon craters and penetrations. We specifically suggest that cratering behavior and associated equations dominate all impacts in which the shock-pulse duration of the projectile (tp) is shorter than that of the target (tt). We also demonstrate that each penetration hole from space-retrieved surfaces may be assigned a unique projectile size, provided an impact velocity is known or assumed. This calibration seems superior to the traditional ballistic-limit approach.

Cratering and penetration experiments in Teflon targets at velocities from 1 to 7 km/s

NASA Astrophysics Data System (ADS)

Hoerz, Friedrich; Bernhard, Ronald P.; Cintala, Mark J.; See, Thomas H.

1995-02-01

Approximately 20 sq m of protective thermal blankets, largely composed of Teflon, were retrieved from the Long Duration Exposure Facility (LDEF) after the spacecraft had spent approximately 5.7 years in space. Examination of these blankets revealed that they contained thousands of hypervelocity impact features ranging from micron-sized craters to penetration holes several millimeters in diameter. We conducted impact experiments in an effort to reproduce such features and to -- hopefully -- understand the relationships between projectile size and the resulting crater or penetration-hole diameter over a wide range of impact velocity. Such relationships are needed to derive the size- and mass-frequency distribution and flux of natural and man-made particles in low-Earth orbit. Powder propellant and light-gas guns were used to launch soda-lime glass spheres of 3.175 mm (1/8 inch) nominal diameter (Dp) into pure Teflon FEP targets at velocities ranging from 1 to 7 km/s. Target thickness (T) was varied over more than three orders of magnitude from infinite halfspace targets (Dp/T less than 0.1) to very thin films (Dp/T greater than 100). Cratering and penetration of massive Teflon targets is dominated by brittle failure and the development of extensive spall zones at the target's front and, if penetrated, the target's rear side. Mass removal by spallation at the back side of Teflon targets may be so severe that the absolute penetration-hole diameter (Dh) can become larger than that of a standard crater (Dc) at relative target thicknesses of Dp/T = 0.6-0.9. The crater diameter is infinite halfspace Teflon targets increases -- at otherwise constant impact conditions -- with encounter velocity by a factor of V0.44. In contrast, the penetration-hole size is very thin foils (Dp/T greater than 50) is essentially unaffected by impact velocity. Penetrations at target thicknesses intermediate to these extremes will scale with variable exponents of V. Our experimental matrix is sufficiently systematic and complete, up to 7 km/s, to make reasonable recommendations for the velocity-scaling of Teflon craters and penetrations. We specifically suggest that cratering behavior and associated equations dominate all impacts in which the shock-pulse duration of the projectile (tp) is shorter than that of the target (tt). We also demonstrate that each penetration hole from space-retrieved surfaces may be assigned a unique projectile size, provided an impact velocity is known or assumed. This calibration seems superior to the traditional ballistic-limit approach.

Mobile Technology Application for Improved Urine Concentration Measurement Pilot Study.

PubMed

Walawender, Laura; Patterson, Jeremy; Strouse, Robert; Ketz, John; Saxena, Vijay; Alexy, Emily; Schwaderer, Andrew

2018-01-01

Objectives: Low hydration has a deleterious effect on many conditions. In the absence of a urine concentrating defect, urine concentration is a marker of hydration status. However, markers to evaluate hydration status have not been well studied in children. The objectives of this paper are to compare measures of thirst and urine concentration in children and to develop a novel mobile technology application to measure urine concentration. Study Design: Children age 12-17 years were selected ( n = 21) for this pilot study. Thirst perception, specific gravity (automated dipstick analysis and refractometer), and urine color scale results were correlated to urine osmolality. The technology department developed a mobile technology camera application to measure light penetrance into urine which was tested on 25 random anonymized urine samples. Results: The patients' thirst perception and color scale as well as two researchers color scale did not significantly correlate with osmolality. Correlation between osmolality and hydration markers resulted in the following Pearson coefficients: SG automated dipstick, 0.61 ( P 0.003); SG refractometer, 0.98 ( P < 0.0001); urine color scale (patient), 0.37 ( P 0.10), and light penetrance, -0.77 ( P < 0.0001). The correlation of light penetrance with osmolality was stronger than all measures except SG by refractometer and osmolality. Conclusion: The mobile technology application may be a more accurate tool for urine concentration measurement than specific gravity by automated dipstick, subjective thirst, and urine color scale, but lags behind specific gravity measured by refractometer. The mobile technology application is a step toward patient oriented hydration strategies.

Electromagnetic induction imaging of concealed metallic objects by means of resonating circuits

NASA Astrophysics Data System (ADS)

Guilizzoni, R.; Watson, J. C.; Bartlett, P. A.; Renzoni, F.

2016-05-01

An electromagnetic induction system, suitable for 2D imaging of metallic samples of different electrical conductivities, has been developed. The system is based on a parallel LCR circuit comprising a ferrite-cored coil (7.8 mm x 9.5 mm, L=680 μH at 1 KHz), a variable resistor and capacitor. The working principle of the system is based on eddy current induction inside a metallic sample when this is introduced into the AC magnetic field created by the coil. The inductance of the LCR circuit is modified due to the presence of the sample, to an extent that depends on its conductivity. Such modification is known to increase when the system is operated at its resonant frequency. Characterizing different metals based on their values of conductivity is therefore possible by utilizing a suitable system operated at resonance. Both imaging and material characterization were demonstrated by means of the proposed electromagnetic induction technique. Furthermore, the choice of using a system with an adjustable resonant frequency made it possible to select resonances that allow magnetic-field penetration through conductive screens. Investigations on the possibility of imaging concealed metals by penetrating such shields have been carried out. A penetration depth of δ~3 mm through aluminium (Al) was achieved. This allowed concealed metallic samples- having conductivities ranging from 0.54 to 59.77 MSm-1 and hidden behind 1.5-mm-thick Al shields- to be imaged. Our results demonstrate that the presence of the concealed metallic objects can be revealed. The technique was thus shown to be a promising detection tool for security applications.

Deceleration of probe beam by stage bias potential improves resolution of serial block-face scanning electron microscopic images.

PubMed

Bouwer, James C; Deerinck, Thomas J; Bushong, Eric; Astakhov, Vadim; Ramachandra, Ranjan; Peltier, Steven T; Ellisman, Mark H

2017-01-01

Serial block-face scanning electron microscopy (SBEM) is quickly becoming an important imaging tool to explore three-dimensional biological structure across spatial scales. At probe-beam-electron energies of 2.0 keV or lower, the axial resolution should improve, because there is less primary electron penetration into the block face. More specifically, at these lower energies, the interaction volume is much smaller, and therefore, surface detail is more highly resolved. However, the backscattered electron yield for metal contrast agents and the backscattered electron detector sensitivity are both sub-optimal at these lower energies, thus negating the gain in axial resolution. We found that the application of a negative voltage (reversal potential) applied to a modified SBEM stage creates a tunable electric field at the sample. This field can be used to decrease the probe-beam-landing energy and, at the same time, alter the trajectory of the signal to increase the signal collected by the detector. With decelerated low landing-energy electrons, we observed that the probe-beam-electron-penetration depth was reduced to less than 30 nm in epoxy-embedded biological specimens. Concurrently, a large increase in recorded signal occurred due to the re-acceleration of BSEs in the bias field towards the objective pole piece where the detector is located. By tuning the bias field, we were able to manipulate the trajectories of the  primary and secondary electrons, enabling the spatial discrimination of these signals using an advanced ring-type BSE detector configuration or a standard monolithic BSE detector coupled with a blocking aperture.

Detecting Near-Surface Ice Formation Over Time Using the Kennaugh Elements Approach From TerraSAR-X

NASA Astrophysics Data System (ADS)

Fernandes, L.

2016-12-01

The summer melting has increased substantially at higher elevations on the Canadian Arctic ice caps. The resulting meltwater percolates into the upper layers of snow and firn and then refreeze, building massive ice bodies. It seems likely that these within-firn ice bodies now limit meltwater penetration into the firn and may be creating a feedback whereby the fraction of melt that runs off to the ocean is increasing. Although changes in firn structure as presence of ice layers and ice bodies are well documented over the Devon ice cap, the firm has shown that it exerts a crucial role to predict more accurately the contribution of small ice caps to the sea level rise. However it is still challenging to assess the extent of these features within the shallow subsurface using ice cores and GPR (Ground Penetrating Radar) data collected along a limited number of linear transects. Studying changes in the distribution of ice bodies' formation over time has the potential to provide information about how the growth of ice bodies in the firn is affecting the pattern of water flow in the firn layer. The objective is investigate the potential of Kennaugh Elements (KE) derived from x-band SAR (Synthetic Aperture Radar) for mapping the distribution and growth of large ice bodies within the firn and the evolution of their distribution over time. The evaluation of this method could reveal a new approach suitable for other glacierized regions that would reduce the costs and amount of field work for studying such properties.

Below-ground attributes on reclaimed surface minelands over a 40-year chronosequence

NASA Astrophysics Data System (ADS)

Limb, Ryan; Bohrer, Stefanie; Volk, Jay

2017-04-01

Reclamation following mining activities often aims to restore stable soils that support productive and diverse native plant communities. The soil re-spread process increases soil compaction, which may alter soil water, plant composition, rooting depths and soil organic matter. This may have a direct impact on vegetation establishment and species recruitment. Seasonal wet/dry and freeze/thaw patterns are thought to alleviate soil compaction over time. However, this has not been formally evaluated on reclaimed landscapes at large scales. Our objectives were to (1) determine soil compaction alleviation, (2) rooting depth and (3) spatial patterns of soil water content over a time-since-reclamation gradient. Soil resistance to penetration varied by depth, with shallow compaction remaining unchanged, but deeper compaction increased over time rather than being alleviated. Root biomass and depth did not increase with time and was consistently less than reference locations. Plant communities initially had a strong native component, but quickly became dominated by invasive species following reclamation and soil water content became increasingly homogeneous over the 40-year chronosequence. Seasonal weather patterns and soil organic matter additions can reduce soil compaction if water infiltration is not limited. Shallow and strongly fibrous-rooted grasses present in reclaimed sites added organic matter to shallow soil layers, but did not penetrate the compacted layers and allow water infiltration. Strong linkages between land management strategies, soil properties and vegetation composition can advance reclamation efforts and promote heterogeneous landscapes. However, current post-reclamation management strategies are not facilitating natural seasonal weather patterns to reducing soil compaction.

In vitro percutaneous penetration and characterization of silver from silver-containing textiles

PubMed Central

Bianco, Carlotta; Kezic, Sanja; Crosera, Matteo; Svetličić, Vesna; Šegota, Suzana; Maina, Giovanni; Romano, Canzio; Larese, Francesca; Adami, Gianpiero

2015-01-01

The objective of this study was to determine the in vitro percutaneous penetration of silver and characterize the silver species released from textiles in different layers of full thickness human skin. For this purpose, two different wound dressings and a garment soaked in artificial sweat were placed in the donor compartments of Franz cells for 24 hours. The concentration of silver in the donor phase and in the skin was determined by an electrothermal atomic absorption spectrometer (ET-AAS) and by inductively coupled plasma mass spectrometer (ICP-MS). The characterization of silver species in the textiles and in the skin layers was made by scanning electron microscopy with integrated energy dispersive X-ray spectroscopy (SEM-EDX). Additionally, the size distribution of silver nanoparticles in the textiles was performed by atomic force microscopy (AFM). On the surface of all investigated materials, silver nanoparticles of different size and morphology were found. Released silver concentrations in the soaking solutions (ie, exposure concentration) ranged from 0.7 to 4.7 μg/mL (0.6–4.0 μg/cm2), fitting the bactericidal range. Silver and silver chloride aggregates at sizes of up to 1 μm were identified both in the epidermis and dermis. The large size of these particles suggests that the aggregation occurred in the skin. The formation of these aggregates likely slowed down the systemic absorption of silver. Conversely, these aggregates may form a reservoir enabling prolonged release of silver ions, which might lead to local effects. PMID:25792824

Return-to-sensibility problems after penetrating captive bolt stunning of cattle in commercial beef slaughter plants.

PubMed

Grandin, Temple

2002-11-01

To evaluate efficacy of penetrating captive bolt stunning of cattle in commercial beef slaughter plants and identify potential causes of a return to sensibility among stunned cattle. Observational study. 21 federally inspected commercial beef slaughter plants. In each plant, stunning of at least 100 cattle (19 large plants) or a minimum of 1 hour of production (2 small plants) was observed, and cattle were evaluated for signs of returning to sensibility on the bleed rail. Cattle with a limp, flaccid head, a lack of spontaneous blinking, and an absence of a righting reflex were considered insensible. In 17 of the 21 (81%) plants, all cattle were rendered insensible before they were hoisted onto the bleed rail. The remaining 4 plants had cattle that had signs of returning to sensibility; these cattle were restunned prior to skinning or leg removal. Of 1,826 fed steers and heifers, 3 (0.16%) had signs of returning to sensibility, whereas 8 of 692 (1.2%) bulls and cows did. Return-to-sensibility problems were attributed to storage of stunner cartridges in damp locations, poor maintenance of firing pins, inexperience of the stunner operator (ie, shooting cattle too high on the forehead), misfiring of the stunner because of a dirty trigger, and stunning of cattle with thick, heavy skulls. Results suggest that efficiency of captive bolt stunning of cattle in commercial slaughter plants can be safely and objectively assessed. Care should be taken to maintain stunners correctly, particularly when stunning bulls and cows with heavy skulls.

DNA sequence-level analyses reveal potential phenotypic modifiers in a large family with psychiatric disorders.

PubMed

Ryan, Niamh M; Lihm, Jayon; Kramer, Melissa; McCarthy, Shane; Morris, Stewart W; Arnau-Soler, Aleix; Davies, Gail; Duff, Barbara; Ghiban, Elena; Hayward, Caroline; Deary, Ian J; Blackwood, Douglas H R; Lawrie, Stephen M; McIntosh, Andrew M; Evans, Kathryn L; Porteous, David J; McCombie, W Richard; Thomson, Pippa A

2018-06-07

Psychiatric disorders are a group of genetically related diseases with highly polygenic architectures. Genome-wide association analyses have made substantial progress towards understanding the genetic architecture of these disorders. More recently, exome- and whole-genome sequencing of cases and families have identified rare, high penetrant variants that provide direct functional insight. There remains, however, a gap in the heritability explained by these complementary approaches. To understand how multiple genetic variants combine to modify both severity and penetrance of a highly penetrant variant, we sequenced 48 whole genomes from a family with a high loading of psychiatric disorder linked to a balanced chromosomal translocation. The (1;11)(q42;q14.3) translocation directly disrupts three genes: DISC1, DISC2, DISC1FP and has been linked to multiple brain imaging and neurocognitive outcomes in the family. Using DNA sequence-level linkage analysis, functional annotation and population-based association, we identified common and rare variants in GRM5 (minor allele frequency (MAF) > 0.05), PDE4D (MAF > 0.2) and CNTN5 (MAF < 0.01) that may help explain the individual differences in phenotypic expression in the family. We suggest that whole-genome sequencing in large families will improve the understanding of the combined effects of the rare and common sequence variation underlying psychiatric phenotypes.

Assessment and Requirements of Nuclear Reaction Databases for GCR Transport in the Atmosphere and Structures

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Wilson, J. W.; Shinn, J. L.; Tripathi, R. K.

1998-01-01

The transport properties of galactic cosmic rays (GCR) in the atmosphere, material structures, and human body (self-shielding) am of interest in risk assessment for supersonic and subsonic aircraft and for space travel in low-Earth orbit and on interplanetary missions. Nuclear reactions, such as knockout and fragmentation, present large modifications of particle type and energies of the galactic cosmic rays in penetrating materials. We make an assessment of the current nuclear reaction models and improvements in these model for developing required transport code data bases. A new fragmentation data base (QMSFRG) based on microscopic models is compared to the NUCFRG2 model and implications for shield assessment made using the HZETRN radiation transport code. For deep penetration problems, the build-up of light particles, such as nucleons, light clusters and mesons from nuclear reactions in conjunction with the absorption of the heavy ions, leads to the dominance of the charge Z = 0, 1, and 2 hadrons in the exposures at large penetration depths. Light particles are produced through nuclear or cluster knockout and in evaporation events with characteristically distinct spectra which play unique roles in the build-up of secondary radiation's in shielding. We describe models of light particle production in nucleon and heavy ion induced reactions and make an assessment of the importance of light particle multiplicity and spectral parameters in these exposures.

Penetration in GTA welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heiple, C.R.; Burgardt, P.

1990-01-01

The size and shape of the weld bead produced in GTA welding depends on the magnitude and distribution of the energy incident on the workpiece surfaces as well as the dissipation of that energy in the workpiece. The input energy is largely controllable through the welding parameters selected, however the dissipation of that energy in the workpiece is less subject to control. Changes in energy dissipation can produce large changes in weld shape or penetration. Heat transport away from the weld pool is almost entirely by conduction, but heat transport in the weld pool is more complicated. Heat conduction throughmore » the liquid is an important component, but heat transport by convection (mass transport) is often the dominant mechanism. Convective heat transport is directional and changes the weld pool shape from that produced by conduction alone. Surface tension gradients are often the dominant forces driving fluid flow in GTA weld pools. These gradients are sensitive functions of weld pool chemistry and the energy input distribution to the weld. Experimental and theoretical work conducted primarily in the past decade has greatly enhanced our understanding of weld pool fluid flow, the forces which drive it, and its effects on weld pool shape. This work is reviewed here. While less common, changes in energy dissipation through the unmelted portion of the workpiece can also affect fusion zone shape or penetration. These effects are also described. 41 refs., 9 figs.« less

A STUDY TO DETERMINE THE FEASIBILITY OF USING A GROUND-PENETRATING RADAR FOR MORE EFFECTIVE REMEDIATION OF SUBSURFACE CONTAMINATION

EPA Science Inventory

A study was conducted (1) to assess the capability of groundpenetrating radar (GPR) to identify natural subsurface features, detect man-made objects burled in the soil, and both detect and define the extent of contaminated soil or ground water due to a toxic spill, and (2) to det...

Beyond the Field Trip: Teaching Tourism through Tours

ERIC Educational Resources Information Center

Kelner, Shaul; Sanders, George

2009-01-01

A course in the sociology of tourism offers an opportunity to examine a world-transforming force that is penetrating more and more aspects of social life. It also offers an opportunity to create a learning environment that uses the object of study as the medium of study. This article examines how instructors can use tourism to teach the sociology…

Methods Improvement of the Fluorescent Penetrant Inspection (FPI) Process.

DTIC Science & Technology

1980-10-01

also affect his ability. There has bieen recetnt eff’o to automiate V14. unfo~rtunatelyv, the humnan factors of’ F14I currentl lv cannot be replaced liY...control, and (6) human factors like variability of training, experience, and job interest. TECHNICAL APPROACH The objective of’ Phase II was to evaluate

Chest computed tomography for penetrating thoracic trauma after normal screening chest roentgenogram.

PubMed

Mollberg, Nathan M; Wise, Stephen R; De Hoyos, Alberto L; Lin, Fang-Ju; Merlotti, Gary; Massad, Malek G

2012-06-01

Chest computed tomography (CCT) is a method of screening for intrathoracic injuries in hemodynamically stable patients with penetrating thoracic trauma. The objective of this study was to examine the changes in utilization of CCT over time and evaluate its contribution to guiding therapeutic intervention. A level 1 trauma center registry was queried between 2006 and 2011. Patients undergoing CCT in the emergency department after penetrating thoracic trauma as well as patients undergoing thoracic operations for penetrating thoracic trauma were identified. Patient demographics, operative indications, use of CCT, injuries, and hospital admissions were analyzed. In all, 617 patients had CCTs performed, of whom 61.1% (371 of 617) had a normal screening plain chest radiograph (CXR). In 14.0% (51 of 371) of these cases, the CCT revealed findings not detected on screening CXR. The majority of these injuries were occult pneumothoraces or hemothoraces (84.3%; 43 of 51), of which 27 (62.8%) underwent tube thoracostomy. In only 0.5% (2 of 371), did the results of CCT alone lead to an operative indication: exploration for hemopericardium. The use of CCT in our patients significantly increased overall (28.8% to 71.4%) as well as after a normal screening CXR (23.3% to 74.6%) over the study period. The use of CCT for penetrating thoracic trauma increased 3.5-fold during the study period with a concurrent increase in findings of uncertain clinical significance. Patients with a normal screening CXR should be triaged with 3-hour delayed CXR, serial physical examinations, and focused assessment with sonography for trauma; and CCT should only be used selectively as a diagnostic modality. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Competition in hospital and health insurance markets: a review and research agenda.

PubMed Central

Morrisey, M A

2001-01-01

OBJECTIVES: To review the empirical literature on the effects of selective contracting and hospital competition on hospital prices, travel distance, services, and quality; to review the effects of managed care penetration and competition on health insurance premiums; and to identify areas for further research. PRINCIPAL FINDINGS: Selective contracting has allowed managed care plans to obtain lower prices from hospitals. This finding is generalizable beyond California and is stronger when there is more competition in the hospital market. Travel distances to hospitals of admission have not increased as a result of managed care. Evidence on the diffusion of technology in hospitals and the extent to which hospitals have specialized as a result of managed care is mixed. Little research on the effects on quality has been undertaken, but preliminary evidence suggests that hospital quality has not declined and may have improved. Actual mergers in the hospital market have not affected hospital prices. Much less research has been focused on managed care markets. Greater market penetration and greater competition among managed care plans are associated with lower managed care premiums. Greater HMO penetration appears to be much more effective than PPO penetration in leading to lower premiums. While workers are willing to change plans when faced with higher out-of-pocket premiums, there is little evidence of the willingness of employers to switch plan offerings. Preliminary evidence suggests that greater managed care penetration has led to lower overall employer premiums, but the results differ substantially between employers with and without a self-insured plan. CONCLUSIONS: Much more research is needed to examine all aspects of managed care markets. In hospital markets, particular attention should be focused on the effects on quality and technology diffusion. PMID:11327174

Emergency department thoracotomy for penetrating injuries of the heart and great vessels: an appraisal of 283 consecutive cases from two urban trauma centers.

PubMed

Seamon, Mark J; Shiroff, Adam M; Franco, Michael; Stawicki, S Peter; Molina, Ezequiel J; Gaughan, John P; Reilly, Patrick M; Schwab, C William; Pryor, John P; Goldberg, Amy J

2009-12-01

Historically, patients with penetrating cardiac injuries have enjoyed the best survival after emergency department thoracotomy (EDT), but further examination of these series reveals a preponderance of cardiac stab wound (SW) survivors with only sporadic cardiac gunshot wound (GSW) survivors. Our primary study objective was to determine which patients requiring EDT for penetrating cardiac or great vessel (CGV) injury are salvageable. All patients who underwent EDT for penetrating CGV injuries in two urban, level I trauma centers during 2000 to 2007 were retrospectively reviewed. Demographics, injury (mechanism, anatomic injury), prehospital care, and physiology (signs of life [SOL], vital signs, and cardiac rhythm) were analyzed with respect to hospital survival. The study population (n = 283) comprised young (mean age, 27.1 years +/- 10.1 years) men (96.1%) injured by gunshot (GSW, 88.3%) or SWs (11.7%). Patients were compared by injury mechanism and number of CGV wounds with respect to survival (SW, 24.2%; GSW, 2.8%; p < 0.001; single, 9.5%; multiple, 1.4%; p = 0.003). Three predictors-injury mechanism, ED SOL, and number of CGV wounds-were then analyzed alone and in combination with respect to hospital survival. Only one patient (0.8%) with multiple CGV GSW survived EDT. When the cumulative impact of penetrating injury mechanism, ED SOL, and number of CGV wounds was analyzed together, we established that those sustaining multiple CGV GSWs (regardless of ED SOL) were nearly unsalvageable. These results indicate that when multiple CGV GSWs are encountered after EDT, further resuscitative efforts may be terminated without limiting the opportunity for survival.

Optimal area of lateral mass mini-screws implanted in plated cervical laminoplasty: a radiography anatomy study.

PubMed

Chen, Hua; Li, Huibo; Deng, Yuxiao; Rong, Xin; Gong, Quan; Li, Tao; Song, Yueming; Liu, Hao

2017-04-01

Lateral mass mini-screws used in plated cervical laminoplasty might penetrate into facet joints. The objective is to observe this complication incidence and to identify the optimal areas for 5- and 7-mm-long mini-screws to implant on lateral mass. 47 patients who underwent plated cervical laminoplasty were included. The optimal area for mini-screws implanting was set according to pre-operative 3D CT reconstruction data. Then, each posterior-lateral mass surface was divided into three regions: 7-mm region, 5-mm region, and dangerous area. The mini-screw implanted region was recorded. Post-operative CT images were used to identify whether the mini-screws penetrated into facet joints. 235 mini-plates and 470 lateral mass mini-screws were used in the study. 117 (24.9%) mini-screws penetrated 88 (37.4%) facet joints. The 5-mm-long mini-screw optimal area occupied the upper 72, 65, 65, 64, and 65 % area of the posterior-lateral mass surface for C3-7, while the 7-mm-long mini-screw optimal area encompassed the upper 54, 39, 40, 33, and 32 %. Only 7-mm-long mini-screws were used to fix the plate to the lateral mass. 4 of 240 mini-screws in 7-mm region, 67 of the 179 mini-screws in 5-mm region, and 46 of the 51 mini-screws in dangerous region penetrated into the facet joint. The differences in the rate of facet joint penetration related to region were statistically significant (P < 0.001). The facet joint destruction by mini-screws was not a rare complication in plated cervical laminoplasty. The optimal areas we proposed may help guide the mini-screw implantation positions.

Effect of lavage and brush preparation on cement penetration and primary stability in tibial unicompartmental total knee arthroplasty: An experimental cadaver study.

PubMed

Scheele, Christian; Pietschmann, Matthias F; Schröder, Christian; Grupp, Thomas; Holderied, Melanie; Jansson, Volmar; Müller, Peter E

2017-03-01

Unicompartmental total knee arthroplasty (UKA) is a well-established treatment option for unicondylar osteoarthritis, and generally leads to better functional results than tricompartimental total knee arthroplasty (TKA). However, revision rates of UKAs are reported as being higher; a major reason for this is aseptic loosening of the tibial component due to implant-cement-bone interface fatigue. The objective of this study was to determine the effects of trabecular bone preparation, prior to implantation of tibial UKAs, on morphological and biomechanical outcomes in a cadaver study. Cemented UKAs were performed in 18 human cadaver knees after the bone bed was cleaned using pulsed lavage (Group A), conventional brush (Group B) or no cleaning at all (Group C, control). Morphologic cement penetration and primary stability were measured. The area proportion under the tibial component without visible cement penetration was significantly higher in Group C (21.9%, SD 11.9) than in both Group A (7.1%, SD 5.8), and Group B (6.5%, SD 4.2) (P=0.007). The overall cement penetration depth did not differ between groups. However, in the posterior part, cement penetration depth was significantly higher in Group B (1.9mm, SD 0.3) than in both Group A (1.3mm, SD 0.3) and Group C (1.4mm, SD 0.3) (P=0.015). The mode of preparation did not show a substantial effect on primary stability tested under dynamic compression-shear test conditions (P=0.910). Bone preparation significantly enhances cement interdigitation. The application of a brush shows similar results compared with the application of pulsed lavage. Copyright © 2016 Elsevier B.V. All rights reserved.

Simulation of laser propagation through a three-layer human skin model in the spectral range from 1000 to 1900 nm.

PubMed

Nasouri, Babak; Murphy, Thomas E; Berberoglu, Halil

2014-01-01

For understanding the mechanisms of low-level laser/light therapy (LLLT), accurate knowledge of light interaction with tissue is necessary. We present a three-dimensional, multilayer reduced-variance Monte Carlo simulation tool for studying light penetration and absorption in human skin. Local profiles of light penetration and volumetric absorption were calculated for uniform as well as Gaussian profile beams with different spreads over the spectral range from 1000 to 1900 nm. The results showed that lasers within this wavelength range could be used to effectively and safely deliver energy to specific skin layers as well as achieve large penetration depths for treating deep tissues, without causing skin damage. In addition, by changing the beam profile from uniform to Gaussian, the local volumetric dosage could increase as much as three times for otherwise similar lasers. We expect that this tool along with the results presented will aid researchers in selecting wavelength and laser power in LLLT.

Gas-Stabilizing Gold Nanocones for Acoustically Mediated Drug Delivery.

PubMed

Mannaris, Christophoros; Teo, Boon M; Seth, Anjali; Bau, Luca; Coussios, Constantin; Stride, Eleanor

2018-06-01

The efficient penetration of drugs into tumors is a major challenge that remains unmet. Reported herein is a strategy to promote extravasation and enhanced penetration using inertial cavitation initiated by focused ultrasound and cone-shaped gold nanoparticles that entrap gas nanobubbles. The cones are capable of initiating inertial cavitation under pressures and frequencies achievable with existing clinical ultrasound systems and of promoting extravasation and delivery of a model large therapeutic molecule in an in vitro tissue mimicking flow phantom, achieving penetration depths in excess of 2 mm. Ease of functionalization and intrinsic imaging capabilities provide gold with significant advantages as a material for biomedical applications. The cones show neither cytotoxicity in Michigan Cancer Foundation (MCF)-7 cells nor hemolytic activity in human blood at clinically relevant concentrations and are found to be colloidally stable for at least 5 d at 37 °C and several months at 4 °C. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The impact of HMO competition on private health insurance premiums, 1985-1992.

PubMed

Wickizer, T M; Feldstein, P J

1995-01-01

A critical unresolved health policy question is whether competition stimulated by managed care organizations can slow the rate of growth in health care expenditures. We analyzed the competitive effects of health maintenance organizations (HMOs) on the growth in fee-for-service indemnity insurance premiums over the period 1985-1992 using premium data on 95 groups that had policies with a single, large, private insurance carrier. We used multiple regressions to estimate the effect of HMO market penetration on insurance premium growth rates. HMO penetration had a statistically significant (p < .015) negative effect on the rate of growth in indemnity insurance premiums. For an average group located in a market whose HMO penetration rate increased by 25% (e.g., from 10% to 12.5%), the real rate of growth in premiums would be approximately 5.9% instead of 7.0%. Our findings indicate that competitive strategies, relying on managed care, have significant potential to reduce health insurance premium growth rates, thereby resulting in substantial cost savings over time.

Simulation of laser propagation through a three-layer human skin model in the spectral range from 1000 to 1900 nm

NASA Astrophysics Data System (ADS)

Nasouri, Babak; Murphy, Thomas E.; Berberoglu, Halil

2014-07-01

For understanding the mechanisms of low-level laser/light therapy (LLLT), accurate knowledge of light interaction with tissue is necessary. We present a three-dimensional, multilayer reduced-variance Monte Carlo simulation tool for studying light penetration and absorption in human skin. Local profiles of light penetration and volumetric absorption were calculated for uniform as well as Gaussian profile beams with different spreads over the spectral range from 1000 to 1900 nm. The results showed that lasers within this wavelength range could be used to effectively and safely deliver energy to specific skin layers as well as achieve large penetration depths for treating deep tissues, without causing skin damage. In addition, by changing the beam profile from uniform to Gaussian, the local volumetric dosage could increase as much as three times for otherwise similar lasers. We expect that this tool along with the results presented will aid researchers in selecting wavelength and laser power in LLLT.

Redox flow batteries with serpentine flow fields: Distributions of electrolyte flow reactant penetration into the porous carbon electrodes and effects on performance

NASA Astrophysics Data System (ADS)

Ke, Xinyou; Prahl, Joseph M.; Alexander, J. Iwan D.; Savinell, Robert F.

2018-04-01

Redox flow batteries with flow field designs have been demonstrated to boost their capacities to deliver high current density and power density in medium and large-scale energy storage applications. Nevertheless, the fundamental mechanisms involved with improved current density in flow batteries with serpentine flow field designs have been not fully understood. Here we report a three-dimensional model of a serpentine flow field over a porous carbon electrode to examine the distributions of pressure driven electrolyte flow penetrations into the porous carbon electrodes. We also estimate the maximum current densities associated with stoichiometric availability of electrolyte reactant flow penetrations through the porous carbon electrodes. The results predict reasonably well observed experimental data without using any adjustable parameters. This fundamental work on electrolyte flow distributions of limiting reactant availability will contribute to a better understanding of limits on electrochemical performance in flow batteries with serpentine flow field designs and should be helpful to optimizing flow batteries.

Dynamic Control of Facts Devices to Enable Large Scale Penetration of Renewable Energy Resources

NASA Astrophysics Data System (ADS)

Chavan, Govind Sahadeo

This thesis focuses on some of the problems caused by large scale penetration of Renewable Energy Resources within EHV transmission networks, and investigates some approaches in resolving these problems. In chapter 4, a reduced-order model of the 500 kV WECC transmission system is developed by estimating its key parameters from phasor measurement unit (PMU) data. The model was then implemented in RTDS and was investigated for its accuracy with respect to the PMU data. Finally it was tested for observing the effects of various contingencies like transmission line loss, generation loss and large scale penetration of wind farms on EHV transmission systems. Chapter 5 introduces Static Series Synchronous Compensators (SSSC) which are seriesconnected converters that can control real power flow along a transmission line. A new application of SSSCs in mitigating Ferranti effect on unloaded transmission lines was demonstrated on PSCAD. A new control scheme for SSSCs based on the Cascaded H-bridge (CHB) converter configuration was proposed and was demonstrated using PSCAD and RTDS. A new centralized controller was developed for the distributed SSSCs based on some of the concepts used in the CHB-based SSSC. The controller's efficacy was demonstrated using RTDS. Finally chapter 6 introduces the problem of power oscillations induced by renewable sources in a transmission network. A power oscillation damping (POD) controller is designed using distributed SSSCs in NYPA's 345 kV three-bus AC system and its efficacy is demonstrated in PSCAD. A similar POD controller is then designed for the CHB-based SSSC in the IEEE 14 bus system in PSCAD. Both controllers were noted to have significantly damped power oscillations in the transmission networks.

Magnetic Imaging: a New Tool for UK National Nuclear Security

NASA Astrophysics Data System (ADS)

Darrer, Brendan J.; Watson, Joe C.; Bartlett, Paul; Renzoni, Ferruccio

2015-01-01

Combating illicit trafficking of Special Nuclear Material may require the ability to image through electromagnetic shields. This is the case when the trafficking involves cargo containers. Thus, suitable detection techniques are required to penetrate a ferromagnetic enclosure. The present study considers techniques that employ an electromagnetic based principle of detection. It is generally assumed that a ferromagnetic metallic enclosure will effectively act as a Faraday cage to electromagnetic radiation and therefore screen any form of interrogating electromagnetic radiation from penetrating, thus denying the detection of any eventual hidden material. In contrast, we demonstrate that it is actually possible to capture magnetic images of a conductive object through a set of metallic ferromagnetic enclosures. This validates electromagnetic interrogation techniques as a potential detection tool for National Nuclear Security applications.

Magnetic Imaging: a New Tool for UK National Nuclear Security

PubMed Central

Darrer, Brendan J.; Watson, Joe C.; Bartlett, Paul; Renzoni, Ferruccio

2015-01-01

Combating illicit trafficking of Special Nuclear Material may require the ability to image through electromagnetic shields. This is the case when the trafficking involves cargo containers. Thus, suitable detection techniques are required to penetrate a ferromagnetic enclosure. The present study considers techniques that employ an electromagnetic based principle of detection. It is generally assumed that a ferromagnetic metallic enclosure will effectively act as a Faraday cage to electromagnetic radiation and therefore screen any form of interrogating electromagnetic radiation from penetrating, thus denying the detection of any eventual hidden material. In contrast, we demonstrate that it is actually possible to capture magnetic images of a conductive object through a set of metallic ferromagnetic enclosures. This validates electromagnetic interrogation techniques as a potential detection tool for National Nuclear Security applications. PMID:25608957

Magnetic imaging: a new tool for UK national nuclear security.

PubMed

Darrer, Brendan J; Watson, Joe C; Bartlett, Paul; Renzoni, Ferruccio

2015-01-22

Combating illicit trafficking of Special Nuclear Material may require the ability to image through electromagnetic shields. This is the case when the trafficking involves cargo containers. Thus, suitable detection techniques are required to penetrate a ferromagnetic enclosure. The present study considers techniques that employ an electromagnetic based principle of detection. It is generally assumed that a ferromagnetic metallic enclosure will effectively act as a Faraday cage to electromagnetic radiation and therefore screen any form of interrogating electromagnetic radiation from penetrating, thus denying the detection of any eventual hidden material. In contrast, we demonstrate that it is actually possible to capture magnetic images of a conductive object through a set of metallic ferromagnetic enclosures. This validates electromagnetic interrogation techniques as a potential detection tool for National Nuclear Security applications.

Incomplete penetrance and variable expressivity of a growth defect as a consequence of knocking out two K(+) transporters in the euascomycete fungus Podospora anserina.

PubMed Central

Lalucque, Hervé; Silar, Philippe

2004-01-01

We describe an example of incomplete penetrance and variable expressivity in the filamentous fungus Podospora anserina, two genetic properties classically associated with mutations in more complex organisms, such as green plants and animals. We show that the knockouts of two TRK-related K(+) transporters of this ascomycete present variability in their phenotype that cannot be attributed to fluctuations of the genetic background or the environment. Thalli of the knockout strains derived from independent monokaryotic ascospores or from a single monokaryotic ascospore and cultivated under standard growth conditions may or may not present impaired growth. When impaired, thalli exhibit a range of phenotypes. Environmental conditions control expressivity to a large extent and penetrance to a low extent. Restoration of functional potassium transport by heterologous expression of K(+) transporters from Neurospora crassa abolishes or strongly diminishes the growth impairment. These data show that incomplete penetrance and variable expressivity can be an intrinsic property of a single Mendelian loss-of-function mutation. They also show that such variability in the expression of a mutant phenotype can be promoted by a phenomenon not obviously related to the well-known chromatin structure modifications, i.e., potassium transport. They provide a framework to understand human channelopathies with similar properties. PMID:15020412

Incomplete penetrance and variable expressivity of a growth defect as a consequence of knocking out two K(+) transporters in the euascomycete fungus Podospora anserina.

PubMed

Lalucque, Hervé; Silar, Philippe

2004-01-01

We describe an example of incomplete penetrance and variable expressivity in the filamentous fungus Podospora anserina, two genetic properties classically associated with mutations in more complex organisms, such as green plants and animals. We show that the knockouts of two TRK-related K(+) transporters of this ascomycete present variability in their phenotype that cannot be attributed to fluctuations of the genetic background or the environment. Thalli of the knockout strains derived from independent monokaryotic ascospores or from a single monokaryotic ascospore and cultivated under standard growth conditions may or may not present impaired growth. When impaired, thalli exhibit a range of phenotypes. Environmental conditions control expressivity to a large extent and penetrance to a low extent. Restoration of functional potassium transport by heterologous expression of K(+) transporters from Neurospora crassa abolishes or strongly diminishes the growth impairment. These data show that incomplete penetrance and variable expressivity can be an intrinsic property of a single Mendelian loss-of-function mutation. They also show that such variability in the expression of a mutant phenotype can be promoted by a phenomenon not obviously related to the well-known chromatin structure modifications, i.e., potassium transport. They provide a framework to understand human channelopathies with similar properties.

The effect of aircraft speed on the penetration of sonic boom noise into a flat ocean

NASA Technical Reports Server (NTRS)

Sparrow, Victor W.

1994-01-01

As U.S. aircraft manufacturers now have focused their HSCT efforts on overwater supersonic flight, a great deal more must be known about sonic booms propagating overwater and interacting with the ocean. For example, it is thought that atmospheric turbulence effects are often much less severe over water than over land. Another important aspect of the overwater flight problems is the penetration of the sonic boom noise into the ocean, where there could be an environmental impact on sea life. This talk will present a brief review on the penetration of sonic boom noise into a large body of water with a flat surface. It has been determined recently that faster supersonic speeds imply greater penetration of sonic boom noise into the ocean. The new theory is derived from the original Sawyers paper and from the knowledge that for level flight a boom's duration is proportional to the quantity M/(M(exp 2)-1)(exp 3/8) where M is the Mach number. It is found that for depths of 10 m or less, the peak SPL varies less than 6 dB over a wide range of M. For greater depths, 100 m for example, increased Mach numbers may increase the SPL by 15 dB or more.

Re-engineering therapeutic antibodies for Alzheimer's disease as blood-brain barrier penetrating bi-specific antibodies.

PubMed

Pardridge, William M

2016-12-01

Therapeutic antibodies are large molecule drugs that do not cross the blood-brain barrier (BBB). Therefore, drug development of therapeutic antibodies for Alzheimer's disease (AD) requires that these molecules be re-engineered to enable BBB delivery. This is possible by joining the therapeutic antibody with a transporter antibody, resulting in the engineering of a BBB-penetrating bispecific antibody (BSA). Areas covered: The manuscript covers transporter antibodies that cross the BBB via receptor-mediated transport systems on the BBB, such as the insulin receptor or transferrin receptor. Furthermore, it highlights therapeutic antibodies for AD that target the Abeta amyloid peptide, beta secretase-1, or the metabotropic glutamate receptor-1. BSAs are comprised of both the transporter antibody and the therapeutic antibody, as well as IgG constant region, which can induce immune tolerance or trigger transport via Fc receptors. Expert opinion: Multiple types of BSA molecular designs have been used to engineer BBB-penetrating BSAs, which differ in valency and spatial orientation of the transporter and therapeutic domains of the BSA. The plasma pharmacokinetics and dosing regimens of BSAs differ from that of conventional therapeutic antibodies. BBB-penetrating BSAs may be engineered in the future as new treatments of AD, as well as other neural disorders.

Targeted Mesoporous Iron Oxide Nanoparticles-Encapsulated Perfluorohexane and a Hydrophobic Drug for Deep Tumor Penetration and Therapy.

PubMed

Su, Yu-Lin; Fang, Jen-Hung; Liao, Chia-Ying; Lin, Chein-Ting; Li, Yun-Ting; Hu, Shang-Hsiu

2015-01-01

A magneto-responsive energy/drug carrier that enhances deep tumor penetration with a porous nano-composite is constructed by using a tumor-targeted lactoferrin (Lf) bio-gate as a cap on mesoporous iron oxide nanoparticles (MIONs). With a large payload of a gas-generated molecule, perfluorohexane (PFH), and a hydrophobic anti-cancer drug, paclitaxel (PTX), Lf-MIONs can simultaneously perform bursting gas generation and on-demand drug release upon high-frequency magnetic field (MF) exposure. Biocompatible PFH was chosen and encapsulated in MIONs due to its favorable phase transition temperature (56 °C) and its hydrophobicity. After a short-duration MF treatment induces heat generation, the local pressure increase via the gasifying of the PFH embedded in MION can substantially rupture the three-dimensional tumor spheroids in vitro as well as enhance drug and carrier penetration. As the MF treatment duration increases, Lf-MIONs entering the tumor spheroids provide an intense heat and burst-like drug release, leading to superior drug delivery and deep tumor thermo-chemo-therapy. With their high efficiency for targeting tumors, Lf-MIONs/PTX-PFH suppressed subcutaneous tumors in 16 days after a single MF exposure. This work presents the first study of using MF-induced PFH gasification as a deep tumor-penetrating agent for drug delivery.

Targeted Mesoporous Iron Oxide Nanoparticles-Encapsulated Perfluorohexane and a Hydrophobic Drug for Deep Tumor Penetration and Therapy

PubMed Central

Su, Yu-Lin; Fang, Jen-Hung; Liao, Chia-Ying; Lin, Chein-Ting; Li, Yun-Ting; Hu, Shang-Hsiu

2015-01-01

A magneto-responsive energy/drug carrier that enhances deep tumor penetration with a porous nano-composite is constructed by using a tumor-targeted lactoferrin (Lf) bio-gate as a cap on mesoporous iron oxide nanoparticles (MIONs). With a large payload of a gas-generated molecule, perfluorohexane (PFH), and a hydrophobic anti-cancer drug, paclitaxel (PTX), Lf-MIONs can simultaneously perform bursting gas generation and on-demand drug release upon high-frequency magnetic field (MF) exposure. Biocompatible PFH was chosen and encapsulated in MIONs due to its favorable phase transition temperature (56 °C) and its hydrophobicity. After a short-duration MF treatment induces heat generation, the local pressure increase via the gasifying of the PFH embedded in MION can substantially rupture the three-dimensional tumor spheroids in vitro as well as enhance drug and carrier penetration. As the MF treatment duration increases, Lf-MIONs entering the tumor spheroids provide an intense heat and burst-like drug release, leading to superior drug delivery and deep tumor thermo-chemo-therapy. With their high efficiency for targeting tumors, Lf-MIONs/PTX-PFH suppressed subcutaneous tumors in 16 days after a single MF exposure. This work presents the first study of using MF-induced PFH gasification as a deep tumor-penetrating agent for drug delivery. PMID:26379789

Penetration and survival of riparian tree roots in compacted coarse gravel mixtures

NASA Astrophysics Data System (ADS)

Muellner, Michael; Weissteiner, Clemens; Konzel, Christoph; Rauch, Hans Peter

2016-04-01

Root growth and penetration of riparian trees along paved cycling paths and service roads of rivers causes often traffic safety problems. Damages occur mostly on street surfaces with thin asphalt layers and especially in the upper part of the pavement structure. The maintainers of these roads are faced with frequent and high annual repair costs in order to guarantee traffic safety and pleasant cycling conditions. Analyses of the dominating process mechanisms demonstrated that mainly the naturally growing pioneer vegetation along rivers is responsible for the asphalt damages caused by their constant and rapid growth. The investigations of the root growth characteristics showed that tree roots mostly penetrate the road structure between the gravel sublayer and the asphalt because of the high compaction of the layer itself. In a second step of the research project the influence of different gravel size mixtures on the root penetration and survival are analysed. Coarse gravel size mixtures with the lowest possible fine granular fraction are suposed to inhibit root growth due to the mechanical impedance and air pruning of roots. Furthermore coarse gravel size mixtures could influence the presence of condensate formed at the underside of the asphalt layer. Therefore seven different compositions of matrix stone gravel size mixtures (0/32, 4/32, 8/32, 16/32, 0/64, 8/64 hydraulic bound mixture and 16/64) as sublayer material were tested in a small scale experimental set-up. Wooden boxes with a dimension of 1x1.5x0.5 m and 0.5x0.5x0.5 m were used as frames for the different matrix stone mixtures. On one side the boxes were delimited to the surrounding soil with a steel mesh followed by a wire mesh and a geotextile. Boxes were located in an 80 cm deep hole on a 30 cm thick drainage layer. Willow and poplar cuttings were planted laterally to the root penetrable side of the boxes. Large boxes were filled and compacted with 6 different gravel size mixtures (all but 4/32) and covered by a 10 cm thick concrete layer, small boxes were filled and compacted with 6 gravel size mixtures (all but hydraulic bound mixture) up to the top of the boxes. In total 18 large boxes and 36 small boxes were constructed. Six month after planting the cuttings, above- and below-ground biomass was analysed for the first 6 large boxes and the first 12 small boxes. Soil moisture conditions were also analysed by 21 soil-moisture sensors (3 in each large box and 3 in the surrounding soil) in order to detect different soil moisture conditions throughout time. First results showed that after six months a slightly increase of root biomass production was detected in the finer gravel size mixtures.

Designing Nordic Technology-Enhanced Learning

ERIC Educational Resources Information Center

Cerratto-Pargman, Teresa; Jarvela, Sanna M.; Milrad, Marcelo

2012-01-01

The latest developments of information and communication technologies (ICT) and its large penetration in different sectors of our society pose new challenges and demands in the field of education. This special issue entitled "Designing Nordic technology-enhanced learning (TEL)", presents and discusses how researchers in the Nordic…

Tomography of the subducting Pacific slab and the 2015 Bonin deepest earthquake (Mw 7.9).

PubMed

Zhao, Dapeng; Fujisawa, Moeto; Toyokuni, Genti

2017-03-15

On 30 May 2015 an isolated deep earthquake (~670 km, Mw 7.9) occurred to the west of the Bonin Islands. To clarify its causal mechanism and its relationship to the subducting Pacific slab, we determined a detailed P-wave tomography of the deep earthquake source zone using a large number of arrival-time data. Our results show that this large deep event occurred within the subducting Pacific slab which is penetrating into the lower mantle. In the Izu-Bonin region, the Pacific slab is split at ~28° north latitude, i.e., slightly north of the 2015 deep event hypocenter. In the north the slab becomes stagnant in the mantle transition zone, whereas in the south the slab is directly penetrating into the lower mantle. This deep earthquake was caused by joint effects of several factors, including the Pacific slab's fast deep subduction, slab tearing, slab thermal variation, stress changes and phase transformations in the slab, and complex interactions between the slab and the ambient mantle.

Marine envenomations.

PubMed

Berling, Ingrid; Isbister, Geoffrey

2015-01-01

Marine stings are common but most are minor and do not require medical intervention. Severe and systemic marine envenoming is uncommon, but includes box jellyfish stings, Irukandji syndrome, major stingray trauma and blue-ringed octopus envenoming. Almost all marine injuries are caused by jellyfish stings, and penetrating injuries from spiny fish, stingrays or sea urchins. This article describes the presentation and management of marine envenomations and injuries that may occur in Australia. First aid for jellyfish includes tentacle removal, application of vinegar for box jellyfish, and hot water immersion (45°C for 20 min) for bluebottle jellyfish stings. Basic life support is essential for severe marine envenomings that result in cardiac collapse or paralysis. Irukandji syndrome causes severe generalised pain, autonomic excess and minimal local pain, which may require large amounts of analgesia, and, uncommonly, myocardial depression and pulmonary oedema occur. Penetrating marine injuries can cause significant trauma depending on location of the injury. Large and unclean wounds may have delayed healing and secondary infection if not adequately irrigated, debrided and observed.

The origin, type and hydrocarbon generation potential of organic matter in a marine-continental transitional facies shale succession (Qaidam Basin, China).

PubMed

Wang, Guo-Cang; Sun, Min-Zhuo; Gao, Shu-Fang; Tang, Li

2018-04-26

This organic-rich shale was analyzed to determine the type, origin, maturity and depositional environment of the organic matter and to evaluate the hydrocarbon generation potential of the shale. This study is based on geochemical (total carbon content, Rock-Eval pyrolysis and the molecular composition of hydrocarbons) and whole-rock petrographic (maceral composition) analyses. The petrographic analyses show that the shale penetrated by the Chaiye 2 well contains large amounts of vitrinite and sapropelinite and that the organic matter within these rocks is type III and highly mature. The geochemical analyses show that these rocks are characterized by high total organic carbon contents and that the organic matter is derived from a mix of terrestrial and marine sources and highly mature. These geochemical characteristics are consistent with the results of the petrographic analyses. The large amounts of organic matter in the Carboniferous shale succession penetrated by the Chaiye 2 well may be due to good preservation under hypersaline lacustrine and anoxic marine conditions. Consequently, the studied shale possesses very good hydrocarbon generation potential because of the presence of large amounts of highly mature type III organic matter.

Methods for Improving In Vitro and In Vivo Boar Sperm Fertility.

PubMed

Funahashi, H

2015-07-01

Fertility of boar spermatozoa is changed after ejaculation in vivo and in vitro. During processing for in vitro fertilization (IVF), although spermatozoa are induced capacitation, resulting in a high penetration rate, persistent obstacle of polyspermic penetration is still observed with a high incidence. For artificial insemination (AI), we still need a large number of spermatozoa and lose a majority of those in the female reproductive tract. Fertility of cryopreserved boar spermatozoa is still injured through freezing and thawing process. In the present brief review, factors affecting fertility of boar sperm during IVF, AI and cryopreservation are discussed in the context of discovering methodologies to improve it. © 2015 Blackwell Verlag GmbH.

A millimeter-wave reflectometer for whole-body hydration sensing

NASA Astrophysics Data System (ADS)

Zhang, W.-D.; Brown, E. R.

2016-05-01

This paper demonstrates a non-invasive method to determine the hydration level of human skin by measuring the reflectance of W-band (75-110 GHz) and Ka-band (26-40 GHz) radiation. Ka-band provides higher hydration accuracy (<1%) and greater depth of penetration (> 1 mm), thereby allowing access to the important dermis layer of skin. W-band provides less depth of penetration but finer spatial resolution (~2 mm). Both the hydration sensing concept and experimental results are presented here. The goal is to make a human hydration sensor that is 1% accurate or better, operable by mechanically scanning, and fast enough to measure large areas of the human body in seconds.

On the Comparison of the Long Penetration Mode (LPM) Supersonic Counterflowing Jet to the Supersonic Screech Jet

NASA Technical Reports Server (NTRS)

Farr, Rebecca A.; Chang, Chau-Lyan; Jones, Jess H.; Dougherty, N. Sam

2015-01-01

Classic tonal screech noise created by under-expanded supersonic jets; Long Penetration Mode (LPM) supersonic phenomenon -Under-expanded counter-flowing jet in supersonic free stream -Demonstrated in several wind tunnel tests -Modeled in several computational fluid dynamics (CFD) simulations; Discussion of LPM acoustics feedback and fluid interactions -Analogous to the aero-acoustics interactions seen in screech jets; Lessons Learned: Applying certain methodologies to LPM -Developed and successfully demonstrated in the study of screech jets -Discussion of mechanically induced excitation in fluid oscillators in general; Conclusions -Large body of work done on jet screech, other aero-acoustic phenomenacan have direct application to the study and applications of LPM cold flow jets

Laboratory-based x-ray phase-contrast tomography enables 3D virtual histology

NASA Astrophysics Data System (ADS)

Töpperwien, Mareike; Krenkel, Martin; Quade, Felix; Salditt, Tim

2016-09-01

Due to the large penetration depth and small wavelength hard x-rays offer a unique potential for 3D biomedical and biological imaging, combining capabilities of high resolution and large sample volume. However, in classical absorption-based computed tomography, soft tissue only shows a weak contrast, limiting the actual resolution. With the advent of phase-contrast methods, the much stronger phase shift induced by the sample can now be exploited. For high resolution, free space propagation behind the sample is particularly well suited to make the phase shift visible. Contrast formation is based on the self-interference of the transmitted beam, resulting in object-induced intensity modulations in the detector plane. As this method requires a sufficiently high degree of spatial coherence, it was since long perceived as a synchrotron-based imaging technique. In this contribution we show that by combination of high brightness liquid-metal jet microfocus sources and suitable sample preparation techniques, as well as optimized geometry, detection and phase retrieval, excellent three-dimensional image quality can be obtained, revealing the anatomy of a cobweb spider in high detail. This opens up new opportunities for 3D virtual histology of small organisms. Importantly, the image quality is finally augmented to a level accessible to automatic 3D segmentation.

Design and implemention of a multi-functional x-ray computed tomography system

NASA Astrophysics Data System (ADS)

Li, Lei; Xi, Xiaoqi; Han, Yu; Yan, Bin; Zhang, Xiang; Deng, Lin; Chen, Siyu; Jin, Zhao; Li, Zengguang

2015-10-01

A powerful volume X-ray tomography system has been designed and constructed to provide an universal tool for the three-dimensional nondestructive testing and investigation of industrial components, automotive, electronics, aerospace components, new materials, etc. The combined system is equipped with two commercial X-ray sources, sharing one flat panel detector of 400mm×400mm. The standard focus 450kV high-energy x-ray source is optimized for complex and high density components such as castings, engine blocks and turbine blades. And the microfocus 225kV x-ray source is to meet the demands of micro-resolution characterization applications. Thus the system's penetration capability allows to scan large objects up to 200mm thick dense materials, and the resolution capability can meet the demands of 20μm microstructure inspection. A high precision 6-axis manipulator system is fitted, capable of offset scanning mode in large field of view requirements. All the components are housed in a room with barium sulphate cement. On the other hand, the presented system expands the scope of applications such as dual energy research and testing. In this paper, the design and implemention of the flexible system is described, as well as the preliminary tomographic imaging results of an automobile engine block.

Desalination of Walls and Façades

NASA Astrophysics Data System (ADS)

Wedekind, W.; Jáuregui Arreola, K.; Siegesmund, S.

2012-04-01

For large monumental objects like walls and façades, the common technique of applying poultices for desalination often are not effective. This practice is neither cost effective nor does it lead to the desired result of desalination. To manage the conservation and desalination of these kinds of objects, several sprinkling techniques are known and have been applied on historical objects. For example, in the wooden warship Vasa, which was excavated from the sea bottom in Stockholm/Sweden, a sprinkling method was applied in 1961 for conservation and desalination. A sprinkling method to desalinate porous mineral materials will be presented using three different case studies: the rock cut monument no. 825 in Petra/Jordan, the medieval monastary church of the former Franziscan convent in Zeitz/Germany and the baroque monastary church Santa Monica in Guadalajara/Mexico. Before to start with practical conservation, the material- and petropysical properties, focoussed on water transport properties, like porosity, pore size distribution, water uptake and drying rate were investigadet. Diagnostic investigations on the objects included the mapping of deterioration, moister content measurements and salt accumulation determined by borehole cuts samples at depth. In the sprinkling method water is sprayed onto the wall surface through nozzels arranged in a modular grid. Depending on the sprinkling duration, a small or a large amount of water seeps into the porous materials, whereby the depth penetration can be adjusted accordingly. The water not absorbed by the stone runs off the facade and can be collected in liter amounts and tested by electrical conductivity with respect to the dissolved substances. After the drying of the wall's surface and the accumulation of salt at the material's surface, the procedure is repeated. For each subsequent washing a lower content of salt should be brought to the surface. Step by step the salt concentration will eventually decrease to almost zero. By application of the sprinkling method several thousand grams of soluble salts can be extracted. A significant reduction of the salt content within the stone can be detected by drilling dust analyses. The specific situation of salt-accumulation and weathering will be illustrated in each case, along with a presentation of the results and the difficulties and experiences of practical desalination.

L-band InSAR Penetration Depth Experiment, North Slope Alaska

NASA Astrophysics Data System (ADS)

Muskett, Reginald

2017-04-01

Since the first spacecraft-based synthetic aperture radar (SAR) mission NASA's SEASAT in 1978 radars have been flown in Low Earth Orbit (LEO) by other national space agencies including the Canadian Space Agency, European Space Agency, India Space Research Organization and the Japanese Aerospace Exploration Agency. Improvements in electronics, miniaturization and production have allowed for the deployment of SAR systems on aircraft for usage in agriculture, hazards assessment, land-use management and planning, meteorology, oceanography and surveillance. LEO SAR systems still provide a range of needful and timely information on large and small-scale weather conditions like those found across the Arctic where ground-base weather radars currently provide limited coverage. For investigators of solid-earth deformation attention must be given to the atmosphere on Interferometric SAR (InSAR) by aircraft and spacecraft multi-pass operations. Because radar has the capability to penetrate earth materials at frequencies from the P- to X-band attention must be given to the frequency dependent penetration depth and volume scattering. This is the focus of our new research project: to test the penetration depth of L-band SAR/InSAR by aircraft and spacecraft systems at a test site in Arctic Alaska using multi-frequency analysis and progressive burial of radar mesh-reflectors at measured depths below tundra while monitoring environmental conditions. Knowledge of the L-band penetration depth on lowland Arctic tundra is necessary to constrain analysis of carbon mass balance and hazardous conditions arising form permafrost degradation and thaw, surface heave and subsidence and thermokarst formation at local and regional scales.

Which Sexual Abuse Victims Receive a Forensic Medical Examination?: The Impact of Children's Advocacy Centers

ERIC Educational Resources Information Center

Walsh, Wendy A.; Cross, Theodore P.; Jones, Lisa M.; Simone, Monique; Kolko, David J.

2007-01-01

Objective: This study examines the impact of Children's Advocacy Centers (CAC) and other factors, such as the child's age, alleged penetration, and injury on the use of forensic medical examinations as part of the response to reported child sexual abuse. Methods: This analysis is part of a quasi-experimental study, the Multi-Site Evaluation of…

A Mars 1984 mission

NASA Technical Reports Server (NTRS)

1977-01-01

Mission objectives are developed for the next logical step in the investigation of the local physical and chemical environments and the search for organic compounds on Mars. The necessity of three vehicular elements: orbiter, penetrator, and rover for in situ investigations of atmospheric-lithospheric interactions is emphasized. A summary report and committee recommendations are included with the full report of the Mars Science Working Group.

Boundary Layer Remote Sensing with Combined Active and Passive Techniques: GPS Radio Occultation and High-Resolution Stereo Imaging (WindCam) Small Satellite Concept

NASA Technical Reports Server (NTRS)

Mannucci, A.J.; Wu, D.L.; Teixeira, J.; Ao, C.O.; Xie, F.; Diner, D.J.; Wood, R.; Turk, Joe

2012-01-01

Objective: significant progress in understanding low-cloud boundary layer processes. This is the Single largest uncertainty in climate projections. Radio occultation has unique features suited to boundary layer remote sensing (1) Cloud penetrating (2) Very high vertical resolution (approximately 50m-100m) (3) Sensitivity to thermodynamic variables

Sediment Acoustics: Wideband Model, Reflection Loss and Ambient Noise Inversion

DTIC Science & Technology

2010-01-01

DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Sediment acoustics : Wideband model , reflection loss and...Physically sound models of acoustic interaction with the ocean floor including penetration, reflection and scattering in support of MCM and ASW needs...OBJECTIVES (1) Consolidation of the BIC08 model of sediment acoustics , its verification in a variety of sediment types, parameter reduction and

Broad-band High-Frequency Sound Interaction With the Seafloor

DTIC Science & Technology

1998-01-01

interface, propagation within and scattering from the seafloor. OBJECTIVES Resolution of modeling issues through experimental measurement of acoustic ...approximation, particularly the roughness scattering mechanism for propagating and evanescent waves, offer alternative models of the observed acoustic ...applicability of each model and it’s relative merits. The candidate models of acoustic penetration include: 1. Biot slow wave 2. Scattering of in-water

Technology assessment of solar energy utilization

NASA Astrophysics Data System (ADS)

Jaeger, F.

1985-11-01

The general objectives and methods of Technology Assessment (TA) are outlined. Typical analysis steps of a TA for solar energy are reviewed: description of the technology and its further development; identification of impact areas; analysis of boundary conditions and definition of scenarios; market penetration of solar technologies; projection of consequences in areas of impact; and assessment of impacts and identification of options for action.

Application of Ground-Penetrating Radar for Detecting Internal Anomalies in Tree Trunks with Irregular Contours.

PubMed

Li, Weilin; Wen, Jian; Xiao, Zhongliang; Xu, Shengxia

2018-02-22

To assess the health conditions of tree trunks, it is necessary to estimate the layers and anomalies of their internal structure. The main objective of this paper is to investigate the internal part of tree trunks considering their irregular contour. In this respect, we used ground penetrating radar (GPR) for non-invasive detection of defects and deteriorations in living trees trunks. The Hilbert transform algorithm and the reflection amplitudes were used to estimate the relative dielectric constant. The point cloud data technique was applied as well to extract the irregular contours of trunks. The feasibility and accuracy of the methods were examined through numerical simulations, laboratory and field measurements. The results demonstrated that the applied methodology allowed for accurate characterizations of the internal inhomogeneity. Furthermore, the point cloud technique resolved the trunk well by providing high-precision coordinate information. This study also demonstrated that cross-section tomography provided images with high resolution and accuracy. These integrated techniques thus proved to be promising for observing tree trunks and other cylindrical objects. The applied approaches offer a great promise for future 3D reconstruction of tomographic images with radar wave.

Relationship between Corporate Governance and Information Security Governance Effectiveness in United States Corporations

ERIC Educational Resources Information Center

Davis, Robert E.

2017-01-01

Cyber attackers targeting large corporations achieved a high perimeter penetration success rate during 2013, resulting in many corporations incurring financial losses. Corporate information technology leaders have a fiduciary responsibility to implement information security domain processes that effectually address the challenges for preventing…

Two Dimensional Heat Transfer around Penetrations in Multilayer Insulation

NASA Technical Reports Server (NTRS)

Johnson, Wesley L.; Kelly, Andrew O.; Jumper, Kevin M.

2012-01-01

The objective of this task was to quantify thermal losses involving integrating MLI into real life situations. Testing specifically focused on the effects of penetrations (including structural attachments, electrical conduit/feedthroughs, and fluid lines) through MLI. While there have been attempts at quantifying these losses both analytically and experimentally, none have included a thorough investigation of the methods and materials that could be used in such applications. To attempt to quantify the excess heat load coming into the system due to the integration losses, a calorimeter was designed to study two dimensional heat transfer through penetrated MLI. The test matrix was designed to take as many variables into account as was possible with the limited test duration and system size. The parameters varied were the attachment mechanism, the buffer material (for buffer attachment mechanisms only), the thickness of the buffer, and the penetration material. The work done under this task is an attempt to measure the parasitic heat loads and affected insulation areas produced by system integration, to model the parasitic loads, and from the model produce engineering equations to allow for the determination of parasitic heat loads in future applications. The methods of integration investigated were no integration, using a buffer to thermally isolate the strut from the MLI, and temperature matching the MLI on the strut. Several materials were investigated as a buffer material including aerogel blankets, aerogel bead packages, cryolite, and even an evacuated vacuum space (in essence a no buffer condition).

Nerve Transfer Surgery for Penetrating Upper Extremity Injuries

PubMed Central

Karamanos, Efstathios; Rakitin, Ilya; Dream, Sophie; Siddiqui, Aamir

2018-01-01

Context Nerve transfer surgery is an option for repair of penetrating injuries of the upper extremity. In the right setting, it has advantages over tendon transfers and nerve grafting. Objective To review our experience since 2006 of nerve transfer surgery in the upper extremities. Design We included cases performed to repair penetrating trauma within three months of injury with at least three years’ follow-up. Main Outcome Measures Preoperative and postoperative muscle strength of the affected extremity. Results All 16 patients were males aged 16 to 43 years. Six patients underwent nerve transfer surgery because of elbow flexion; 5, finger extension; 3, finger flexion; and 2, wrist pronation. Nine patients (56%) had associated vascular injury, and 4 (25%) had fractures. Average follow-up was 6 years. No perioperative complications occurred. Patients had a mean of 3.7 operations after the initial trauma. All patients received physical therapy. All patients improved from 0 of 5 muscle strength preoperatively to a mean of 3.8 (range = 2/5 to 5/5) within 1 year after surgery. In all cases, strength was maintained, and 8 (50%) had continued improvement after Year 1. Ten (63%) returned to their previous employment level. Mean Disabilities of the Arm, Shoulder and Hand score improved from 68 to 83 postoperatively. Conclusion Nerve transfer is a safe, effective technique for correcting penetrating trauma-related nerve injury. In appropriate patients it offers advantages over other techniques. Outcomes can be maintained long term, and many patients can return to their previous level of function. PMID:29702048

Large area x-ray detectors for cargo radiography

NASA Astrophysics Data System (ADS)

Bueno, C.; Albagli, D.; Bendahan, J.; Castleberry, D.; Gordon, C.; Hopkins, F.; Ross, W.

2007-04-01

Large area x-ray detectors based on phosphors coupled to flat panel amorphous silicon diode technology offer significant advances for cargo radiologic imaging. Flat panel area detectors provide large object coverage offering high throughput inspections to meet the high flow rate of container commerce. These detectors provide excellent spatial resolution when needed, and enhanced SNR through low noise electronics. If the resolution is reduced through pixel binning, further advances in SNR are achievable. Extended exposure imaging and frame averaging enables improved x-ray penetration of ultra-thick objects, or "select-your-own" contrast sensitivity at a rate many times faster than LDAs. The areal coverage of flat panel technology provides inherent volumetric imaging with the appropriate scanning methods. Flat panel area detectors have flexible designs in terms of electronic control, scintillator selection, pixel pitch, and frame rates. Their cost is becoming more competitive as production ramps up for the healthcare, nondestructive testing (NDT), and homeland protection industries. Typically used medical and industrial polycrystalline phosphor materials such as Gd2O2S:Tb (GOS) can be applied to megavolt applications if the phosphor layer is sufficiently thick to enhance x-ray absorption, and if a metal radiator is used to augment the quantum detection efficiency and reduce x-ray scatter. Phosphor layers ranging from 0.2-mm to 1-mm can be "sandwiched" between amorphous silicon flat panel diode arrays and metal radiators. Metal plates consisting of W, Pb or Cu, with thicknesses ranging from 0.25-mm to well over 1-mm can be used by covering the entire area of the phosphor plate. In some combinations of high density metal and phosphor layers, the metal plate provides an intensification of 25% in signal due to electron emission from the plate and subsequent excitation within the phosphor material. This further improves the SNR of the system.

Direct Laser Ice Penetrator for Exploring Icy Ocean Worlds: Design, Modeling and Test Results of a Proof-of-Concept Prototype

NASA Astrophysics Data System (ADS)

Hogan, B.; Stone, W.; Bramall, N. E.; Siegel, V.; Lelievre, S.; Rothhammer, B.; Richmond, K.; Flesher, C.

2016-12-01

Subsurface exploration of icy ocean worlds requires an efficient method of penetrating ice to significant depths under extreme environment conditions. Searching for extant life dictates descent to a depth which is habitable or where biomarkers can survive and allow detection. It's anticipated that several meters to 10s of meters of shielding is required to prevent cosmic background radiation and other energetic particles from destroying biomarker evidence. We have devised, developed and demonstrated an entirely novel ice penetrating technology utilizing laser light carried by an optical fiber tether and emitted from a probe's optical nose cone and radiated directly into the volume of ice preceding the penetrator. We have termed it a "Direct Laser Penetrator" or DLP. We present design details, modeling, and test data from preliminary proof-of-concept experiments conducted at Stone Aerospace with results exceeding expectations and achieving the fastest reported thermal probe descent rate to date (> 12 m / hr). DLP has critical benefits over conventional "hot point" melt probes, which must generate large temperature gradients to force heat by conduction through the nose cone, and layers of ice and water. Additionally, hot point melt probes tested under vacuum have shown extreme difficulty initiating penetration, as virtually no thermal contact exists between the probe nose and rough ice surface. The ice simply sublimates and any transferred heat is quickly dissipated due to the low power density and extreme cold. DLP requires NO thermal contact between the probe nose and the ice surface since the laser energy is radiated directly into the volume (vs. surface) of ice preceding the penetrator. A proposed key element of the DLP is the fiber optic tether, coupled with a dedicated sensor fiber, enables "optical access" to the subsurface environment by a lander's shared or DLP dedicated on-board instruments (Raman / Fluorescence / fiber / UV / VIS / NIR spectroscopy, etc). These sensors can search for extant life by detecting biomarkers as well as characterizing the radiation / light environment for subsurface habitability. The combination of a laser penetrator w/ integrated fiber coupled instruments could be an important tool for an icy ocean worlds lander. (Supported by NASA funded SAS projects VALKYRIE and SPINDLE)

In vitro human skin penetration of geraniol and citronellol.

PubMed

Gilpin, Sarah; Hui, Xiaoying; Maibach, Howard

2010-01-01

Geraniol and citronellol are commonly used fragrance components in consumer products. Both are listed as alleged fragrance allergens that should be declared in the European Union when used in cosmetics and consumer products. Such allergenic potential is determined largely by effects on the skin once these materials penetrate and elicit an immune response. Few data demonstrate their penetration abilities or their effects on percutaneous absorption. We wanted to determine the effects of these materials on skin absorption. Skin penetration characterization via flow-through diffusion study serves as a reasonable model for determining dermal dosing for fragrance materials. Such characterization can be used for more accurate safety exposure calculations and regulatory determinations. Extensive comparisons to in vivo data in humans or closely related animals will be required before accepting flow-through diffusion methods as in vivo alternatives by industry and regulatory bodies. To evaluate the penetration abilities of geraniol and citronellol when they are used in a typical vehicle in consumer products. In vitro skin penetration of radiolabeled geraniol and citronellol was studied under occlusion in human cadaver skin, using flow-through diffusion cells for scintillation counting to determine the percentage of dose absorbed. For comparison, two doses of each material were used: 2% and 5% in 3:1 diethyl phthalate/ethanol. After 24 hours, geraniol and citronellol had relatively low skin absorption rates; 3.8% +/- 2.1% of 2% citronellol, 4.7% +/- 1.9% of 5% citronellol, 3.5% +/- 1.9% of 2% geraniol, and 7.3% +/- 1.1% of 5% geraniol were recovered from skin and receptor fluid compartments. These materials showed good mass-balance recovery. The majority of the dose was recovered in the skin washes (a minimum of 64.7% +/- 4.6% recovered for 2% citronellol and a maximum of 79.3% +/- 3.9% recovered for 5% geraniol). Receptor fluid collection points over time showed a linear increase in the amounts of citronellol and geraniol that penetrated the skin, although overall absorption values were quite small. In vitro results indicate that geraniol and citronellol have low potentials for skin penetration, which has implications for their ability to induce allergenicity and for more predictive toxicologic profiling of these materials. In vivo studies should be done to correlate the in vitro results.

The effectiveness of cut-proof glove liners: cut and puncture resistance, dexterity, and sensibility.

PubMed

Salkin, J A; Stuchin, S A; Kummer, F J; Reininger, R

1995-11-01

Five types of commercial glove liners (within double latex gloves) were compared to single and double latex gloves for cut and puncture resistance and for relative manual dexterity and degree of sensibility. An apparatus was constructed to test glove-pseudofinger constructs in either a cutting or puncture mode. Cutting forces, cutting speed, and type of blade (serrated or scalpel blade) were varied and the time to cut-through measured by an electrical conductivity circuit. Penetration forces were similarly determined with a scalpel blade and a suture needle using a spring scale loading apparatus. Dexterity was measured with an object placement task among a group of orthopedic surgeons. Sensibility was assessed with Semmes-Weinstein monofilaments, two-point discrimination, and vibrametry using standard techniques and rating scales. A subjective evaluation was performed at the end of testing. Time to cut-through for the liners ranged from 2 to 30 seconds for a rapid oscillating scalpel and 4 to 40 seconds for a rapid oscillating serrated knife under minimal loads. When a 1 kg load was added, times to cut-through ranged from 0.4 to 1.0 second. In most cases, the liners were superior to double latex. On average, 100% more force was required to penetrate the liners with a scalpel and 50% more force was required to penetrate the liners with a suture needle compared to double latex. Object placement task times were not significantly liners compared to double latex gloves. Semmes-Weinstein monofilaments, two-point discrimination, and vibrametry showed no difference in sensibility among the various liners and double latex gloves. Subjects felt that the liners were minimally to moderately impairing. An acclimation period may be required for their effective use.

Application of x-ray nano-particulate markers for the visualization of intermediate layers and interfaces using scanning electron microscopy

NASA Astrophysics Data System (ADS)

Bessudnova, Nadezda O.; Bilenko, David I.; Zakharevich, Andrey M.

2012-03-01

In this study the methodology of biological sample preparation for dental research using SEM/EDX has been elaborated. (1)The original cutting equipment supplied with 3D user-controlled sample fixation and an adjustable cooling system has been designed and evaluated. (2) A new approach to the root dentine drying procedure has been developed to preserve structure peculiarities of root dentine. (3) A novel adhesive system with embedded X-Ray nanoparticulate markers has been designed. (4)The technique allowing for visualization of bonding resins, interfaces and intermediate layers between tooth hard tissues and restorative materials of endodontically treated teeth using the X-ray nano-particulate markers has been developed and approved. These methods and approaches were used to compare the objective depth of penetration of adhesive systems of different generations in root dentine. It has been shown that the depth of penetration in dentine is less for adhesive systems of generation VI in comparison with bonding resins of generation V, which is in agreement with theoretical evidence. The depth of penetration depends on the correlation between the direction of dentinal tubules, bonding resin delivery and gravity.

Ground penetrating radar for asparagus detection

NASA Astrophysics Data System (ADS)

Seyfried, Daniel; Schoebel, Joerg

2016-03-01

Ground penetrating radar is a promising technique for detection of buried objects. Recently, radar has more and more been identified to provide benefits for a plurality of applications, where it can increase efficiency of operation. One of these fields is the industrial automatic harvesting process of asparagus, which is performed so far by cutting the soil ridge at a certain height including all the asparagus spears and subsequently sieving the latter out of the soil. However, the height where the soil is cut is a critical parameter, since a wrong value leads to either damage of the roots of the asparagus plants or to a reduced crop yield as a consequence of too much biomass remaining in the soil. In this paper we present a new approach which utilizes ground penetrating radar for non-invasive sensing in order to obtain information on the optimal height for cutting the soil. Hence, asparagus spears of maximal length can be obtained, while keeping the roots at the same time undamaged. We describe our radar system as well as the subsequent digital signal processing steps utilized for extracting the information required from the recorded radar data, which then can be fed into some harvesting unit for setting up the optimal cutting height.

Covered Stent-Graft Treatment of Traumatic Internal Carotid Artery Pseudoaneurysms: A Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maras, Dimitrios; Lioupis, Christos; Magoufis, George

Objective. To review the literature concerning the management with placement of covered stent-grafts of traumatic pseudoaneurysms of the extracranial internal carotid artery (ICA) resulting from penetrating craniocervical injuries or skull base fractures. Method. We have reviewed, from the Medline database, all the published cases in the English literature since 1990 and we have added a new case. Results. We identified 20 patients with traumatic extracranial ICA pseudoaneurysms due to penetrating craniocervical injuries or skull base fractures who had been treated with covered stent-graft implantation. Many discrepancies have been ascertained regarding the anticoagulation therapy. In 3 patients the ICA was totallymore » occluded in the follow-up period, giving an overall occlusion rate 15%. No serious complication was reported as a result of the endovascular procedure. Conclusion. Preliminary results suggest that placement of stent-grafts is a safe and effective method of treating ICA traumatic pseudoaneurysms resulting from penetrating craniocervical injuries or skull base fractures. The immediate results are satisfactory when the procedure takes place with appropriate anticoagulation therapy. The periprocedural morbidity and mortality and the early patency are also acceptable. A surveillance program with appropriate interventions to manage restenosis may improve the long-term patency.« less

Optimal Fragmentation and Dispersion of Hazardous Near-Earth Objects

NASA Technical Reports Server (NTRS)

Wie, Bong

2012-01-01

The complex problem of protecting the Earth from the possibility of a catastrophic impact by a hazardous near-Earth object (NEO) has been recently reassessed in [1]. In a letter on NEOs from the White House Office of Science and Technology Policy (OSTP) to the U.S. Senate and Congress in 2010, the White House OSTP strongly recommended that NASA take the lead in conducting research activities for NEO detection, characterization, and deflection technologies. Furthermore, President Obama's new National Space Policy specifically directs NASA to "pursue capabilities, in cooperation with other departments, agencies, and commercial partners, to detect, track, catalog, and characterize NEOs to reduce the risk of harm to humans from an unexpected impact on our planet." The Planetary Defense Task Force of the NASA Advisory Council also recommended that the NASA Office of the Chief Technologist (OCT) begin efforts to investigate asteroid deflection techniques. With national interest growing in the United States, the NEO threat detection and mitigation problem was recently identified as one of NASA's Space Technology Grand Challenges. An innovative solution to NASA's NEO Impact Threat Mitigation Grand Challenge problem was developed through a NIAC Phase I study (9/16/11 - 9/15/12), and it will be further investigated for a NIAC Phase II study (9/10/12 - 9/9/14). Various NEO deflection technologies, including nuclear explosions, kinetic impactors, and slow-pull gravity tractors, have been proposed and examined during the past two decades. Still, there is no consensus on how to reliably deflect or disrupt hazardous NEOs in a timely manner. It is expected that the most probable mission scenarios will have a mission lead time much shorter than 10 years, so the use of nuclear explosives becomes the most feasible method for planetary defense. Direct intercept missions with a short warning time will result in arrival closing velocities of 10-30 kilometers per second with respect to the target asteroid. Given such a large arrival delta V requirement, a rendezvous mission to the target asteroid is infeasible with existing launch vehicles. Furthermore, state-of-the-art penetrating subsurface nuclear explosion technology limits the penetrator's impact velocity to less than approximately 300 meters per second because higher impact velocities prematurely destroy the nuclear fuzing mechanisms. Therefore, significant advances in hypervelocity nuclear interceptor/ penetrator technology must be achieved to enable a last-minute nuclear disruption mission with intercept velocities as high as 30 kilometers per second. Consequently, a HAIV (Hypervelocity Asteroid Intercept Vehicle) mission architecture (Figure 1.1), which blends a hypervelocity kinetic impactor with a subsurface nuclear explosion for optimal fragmentation and dispersion of hazardous NEOs, has been developed through a Phase I study, and it will be further developed and validated through a Phase II study.

Effect of tail plasma sheet conditions on the penetration of the convection electric field in the inner magnetosphere: RCM simulations with self-consistent magnetic field

NASA Astrophysics Data System (ADS)

Gkioulidou, M.; Wang, C.; Lyons, L. R.; Wolf, R.

2009-12-01

Transport of plasma sheet particles into the inner magnetosphere is strongly affected by the penetration of the convection electric field, which is the result of the large-scale magnetosphere ionosphere electromagnetic coupling. This transport, on the other hand, results in plasma heating and magnetic field stretching, which become very significant in the inner plasma sheet (inside 20 RE). We have previously run simulations with the Rice Convection Model (RCM), using the Tsyganenko 96 magnetic field model, to investigate how the earthward penetration of electric field depends on plasma sheet conditions. Outer proton and electron sources at r ~20 RE, are based on 11 years of Geotail data, and realistically represent the mixture of cold and hot plasma sheet population as a function of MLT and interplanetary conditions. We found that shielding of the inner magnetosphere electric field is more efficient for a colder and denser plasma sheet, which is found following northward IMF, than for the hotter and more tenuous plasma sheet found following southward IMF. Our simulation results so far indicate further earthward penetration of plasma sheet particles in response to enhanced convection if the preceding IMF is southward, which leads to weaker electric field shielding. Recently we have integrated the RCM with a magnetic field solver to obtain magnetic fields that are in force balance with given plasma pressures in the equatorial plane. We expect the self-consistent magnetic field to have a pronounced dawn dusk asymmetry due to the asymmetric inner magnetospheric pressure. This should affect the radial distance and MLT of plasma sheet penetration into the inner magnetosphere. We are currently using this force-balanced and self-consistent model with our realistic boundary conditions to evaluate the dependence of the shielding timescale on pre-existing plasma sheet number density and temperature and to more quantitatively determine the correlation between the plasma sheet conditions and spatial distribution of the penetrating particles. Our results are potentially crucial to understanding the contribution of plasma sheet penetration to the development of the storm-time ring current.

A globalization-oriented perspective on health, inequality and socio-economic development.

PubMed

Tausch, Arno

2012-01-01

There has been an attention to inequality as a causal factor for deficient health in the medical journals over the last decades (Richard G. Wilkinson et al. and Schnell et al.); however, the reasons for inequality and the interactions of the underlying causes of inequality at the level of the world economy have not yet been properly explored in this kind of literature. The aim of this article is to provide a new, globalization-oriented, multi-disciplinary perspective on life expectancy, under-five mortality, inequality and socio-economic development in the world system, compatible with the advances in international sociological research on the subject over the last three decades. Taking up the traditions of quantitative sociology to study the effects of multinational corporation (MNC) penetration as a key determining variable for development outcomes such as socio-economic inequality and infant mortality, this article analyzes from the perspective of quantitative political science and economics this particular role of MNC penetration as the key variable for the determination of health, inequality and socio-economic development in 183 countries of the world system, using international social science standard data. As correctly predicted by quantitative sociology, but largely overlooked by the medical profession, the development style, implied by a high MNC penetration of their host countries, reflects the oligopolistic power, which transnational corporations wield over local economies. We took up an idea from Austro-American economist Joseph Alois Schumpeter (1883-1950), which states that the long-term effects of oligopolistic power are negative and lead toward economic and social stagnation. Our data show that although MNC penetration indeed led to certain short-term growth effects after 1990, today, social polarization and stagnation increase as a consequence of the development model, based on high MNC penetration. There is a negative trade-off between MNC penetration and health, both in terms of life expectancy and avoiding under-five mortality. But it can be shown for the 115 countries with complete data that Richard G. Wilkinson's hypothesis still plays an important role in explaining deficient health development in the world system, once we control for the effects of MNC penetration-driven globalization. Copyright © 2012 John Wiley & Sons, Ltd.

Selective Nonoperative Management of Penetrating Abdominal Solid Organ Injuries

PubMed Central

Demetriades, Demetrios; Hadjizacharia, Pantelis; Constantinou, Costas; Brown, Carlos; Inaba, Kenji; Rhee, Peter; Salim, Ali

2006-01-01

Objective: To assess the feasibility and safety of selective nonoperative management in penetrating abdominal solid organ injuries. Background: Nonoperative management of blunt abdominal solid organ injuries has become the standard of care. However, routine surgical exploration remains the standard practice for all penetrating solid organ injuries. The present study examines the role of nonoperative management in selected patients with penetrating injuries to abdominal solid organs. Patients and Methods: Prospective, protocol-driven study, which included all penetrating abdominal solid organ (liver, spleen, kidney) injuries admitted to a level I trauma center, over a 20-month period. Patients with hemodynamic instability, peritonitis, or an unevaluable abdomen underwent an immediate laparotomy. Patients who were hemodynamically stable and had no signs of peritonitis were selected for further CT scan evaluation. In the absence of CT scan findings suggestive of hollow viscus injury, the patients were observed with serial clinical examinations, hemoglobin levels, and white cell counts. Patients with left thoracoabdominal injuries underwent elective laparoscopy to rule out diaphragmatic injury. Outcome parameters included survival, complications, need for delayed laparotomy in observed patients, and length of hospital stay. Results: During the study period, there were 152 patients with 185 penetrating solid organ injuries. Gunshot wounds accounted for 70.4% and stab wounds for 29.6% of injuries. Ninety-one patients (59.9%) met the criteria for immediate operation. The remaining 61 (40.1%) patients were selected for CT scan evaluation. Forty-three patients (28.3% of all patients) with 47 solid organ injuries who had no CT scan findings suspicious of hollow viscus injury were selected for clinical observation and additional laparoscopy in 2. Four patients with a “blush” on CT scan underwent angiographic embolization of the liver. Overall, 41 patients (27.0%), including 18 cases with grade III to V injuries, were successfully managed without a laparotomy and without any abdominal complication. Overall, 28.4% of all liver, 14.9% of kidney, and 3.5% of splenic injuries were successfully managed nonoperatively. Patients with isolated solid organ injuries treated nonoperatively had a significantly shorter hospital stay than patients treated operatively, even though the former group had more severe injuries. In 3 patients with failed nonoperative management and delayed laparotomy, there were no complications. Conclusions: In the appropriate environment, selective nonoperative management of penetrating abdominal solid organ injuries has a high success rate and a low complication rate. PMID:16998371

Akon - A Penetrator for Europa

NASA Astrophysics Data System (ADS)

Jones, Geraint

2016-04-01

Jupiter's moon Europa is one of the most intriguing objects in our Solar System. This 2000km-wide body has a geologically young solid water ice crust that is believed to cover a global ocean of liquid water. The presence of this ocean, together with a source of heating through tidal forces, make Europa a conceivable location for extraterrestrial life. The science case for exploring all aspects of this icy world is compelling. NASA has selected the Europa Mission (formerly Europa Clipper) to study Europa in detail in the 2020s through multiple flybys, and ESA's JUICE mission will perform two flybys of the body in the 2030s. The US agency has extended to the European Space Agency an invitation to provide a contribution to their mission. European scientists interested in Europa science and exploration are currently organizing themselves, in the framework of a coordinated Europa M5 Inititative to study concurrently the main options for this ESA contribution, from a simple addition of individual instruments to the NASA spacecraft, to a lander to investigate Europa's surface in situ. A high speed lander - a penetrator - is by far the most promising technology to achieve this latter option within the anticipated mass constraints, and studies of such a hard lander, many funded by ESA, are now at an advanced level. An international team to formally propose an Europa penetrator to ESA in response to the anticipated ESA M5 call is growing. The working title of this proposal is Akon (Άκων), named after the highly accurate javelin gifted to Europa by Zeus in ancient Greek mythology. We present plans for the Akon penetrator, which would impact Europa's surface at several hundred metres per second, and travel up to several metres into the moon's subsurface. To achieve this, the penetrator would be delivered to the surface by a dedicated descent module, to be destroyed on impact following release of the penetrator above the surface. It is planned that the instruments to be considered for inclusion on the penetrator and its delivery module will address a wide range of scientific topics, from Europa's tenuous atmosphere, surface and near-surface composition, through geophysics and geomorphology, to habitability and astrobiology. An overview of the instrument complement is also provided.

Spatial-temporal Detection of Sea-breeze Penetration Over Megacities from Himawari-8

NASA Astrophysics Data System (ADS)

Ferdiansyah, M. R.; Inagaki, A.; Kanda, M.

2017-12-01

For a coastal urban region, sea breeze is very important for air ventilation and cooling. However, most of sea-breeze monitoring is lacking and inadequate temporally and spatially. Japanese new geostationary meteorological satellite (Himawari-8) has been launched which can provide high resolution satellite imagery. This enables better monitoring of mesoscale weather phenomena such as sea breeze. In this study, we first attempt the feasibility of acquiring temporal-spatial information of sea breeze in a coastal urban region using Himawari-8. For study area, Tokyo (Japan) and Jakarta (Indonesia) area were selected as representative coastal urban regions; both cities located in very distant latitudes. Sea breeze events (Tokyo:16 cases and Jakarta:17 cases) in JAS season of 2015 and 2016 were analyzed. Convergence zones of two sea-breeze systems and delayed sea-breeze penetration were found for both Tokyo and Jakarta. Estimation of inland penetration speed and convergence area for sea breeze event, accompanied by the formation of non-precipitating cumulus type cloudline, is the primary objective. From the visible band image of Himawari-8, cumulus cloudline for each sea breeze event was extracted. The inland penetration speed was then estimated automatically from temporal evolution of these cloudlines. For the case of Tokyo, it was found that the sea breeze from Tokyo Bay had slower penetration speed than another sea breeze (Sagami Bay) coming from a less urbanized area. The average penetration speed of sea-breeze front was estimated to be 3.6 m/s and 1.3 m/s for sea breeze from Sagami Bay and Tokyo Bay, respectively. The penetration differences (from Sagami Bay and Tokyo Bay) could be attributed to the difference in urbanization levels between the coastal areas of Sagami and Tokyo Bay. For the case of Jakarta, the convergence of two sea-breeze systems were found persistent slightly east from the center of Jakarta. Interestingly, the sea-breeze delay was more pronounced in Serpong area, a rapidly growing urban area occupying the western region of Jakarta. On-going work is being conducted to expand the number of coastal cities for analyses.Acknowledgement: This research was supported by the Environment Research and Technology Development Fund (S-14) of the Ministry of the Environment, Japan.

Development of dual sensor hand-held detector

NASA Astrophysics Data System (ADS)

Sezgin, Mehmet

2010-04-01

In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.

A Prototype Scintillating-Fibre Tracker for the Cosmic-ray Muon Tomography of Legacy Nuclear Waste Containers

NASA Astrophysics Data System (ADS)

Kaiser, R.; Clarkson, A.; Hamilton, D. J.; Hoek, M.; Ireland, D. G.; Johnston, J. R.; Keri, T.; Lumsden, S.; Mahon, D. F.; McKinnon, B.; Murray, M.; Nutbeam-Tuffs, S.; Shearer, C.; Staines, C.; Yang, G.; Zimmerman, C.

2014-03-01

Cosmic-ray muons are highly-penetrative charged particles observed at sea level with a flux of approximately 1 cm-2 min-1. They interact with matter primarily through Coulomb scattering which can be exploited in muon tomography to image objects within industrial nuclear waste containers. This paper presents the prototype scintillating-fibre detector developed for this application at the University of Glasgow. Experimental results taken with test objects are shown in comparison to results from GEANT4 simulations. These results verify the simulation and show discrimination between the low, medium and high-Z materials imaged.

Catastrophic Disruption Threshold and Maximum Deflection from Kinetic Impact

NASA Astrophysics Data System (ADS)

Cheng, A. F.

2017-12-01

The use of a kinetic impactor to deflect an asteroid on a collision course with Earth was described in the NASA Near-Earth Object Survey and Deflection Analysis of Alternatives (2007) as the most mature approach for asteroid deflection and mitigation. The NASA DART mission will demonstrate asteroid deflection by kinetic impact at the Potentially Hazardous Asteroid 65803 Didymos in October, 2022. The kinetic impactor approach is considered to be applicable with warning times of 10 years or more and with hazardous asteroid diameters of 400 m or less. In principle, a larger kinetic impactor bringing greater kinetic energy could cause a larger deflection, but input of excessive kinetic energy will cause catastrophic disruption of the target, leaving possibly large fragments still on collision course with Earth. Thus the catastrophic disruption threshold limits the maximum deflection from a kinetic impactor. An often-cited rule of thumb states that the maximum deflection is 0.1 times the escape velocity before the target will be disrupted. It turns out this rule of thumb does not work well. A comparison to numerical simulation results shows that a similar rule applies in the gravity limit, for large targets more than 300 m, where the maximum deflection is roughly the escape velocity at momentum enhancement factor β=2. In the gravity limit, the rule of thumb corresponds to pure momentum coupling (μ=1/3), but simulations find a slightly different scaling μ=0.43. In the smaller target size range that kinetic impactors would apply to, the catastrophic disruption limit is strength-controlled. A DART-like impactor won't disrupt any target asteroid down to significantly smaller size than the 50 m below which a hazardous object would not penetrate the atmosphere in any case unless it is unusually strong.

SOBER-MCS: Sociability-Oriented and Battery Efficient Recruitment for Mobile Crowd-Sensing

PubMed Central

Anjomshoa, Fazel

2018-01-01

The Internet of Things (IoT) concept is aiming at being an integral part of the next generation networking services by introducing pervasiveness and ubiquitous interconnectivity of uniquely-identifiable objects. The massive availability of personalized smart devices such as smartphones and wearables enable their penetration into the IoT ecosystem with their built-in sensors, particularly in Mobile Crowd-Sensing (MCS) campaigns. The MCS systems achieve the objectives of the large-scale non-dedicated sensing concept in the IoT if a sufficient number of participants are engaged to the collaborative data acquisition process. Therefore, user recruitment is a key challenge in MCS, which requires effective incentivization of cooperative, truthful and trustworthy users. A grand concern for the participants is the battery drain on the mobile devices. It is a known fact that battery drain in a smartphone is a function of the user activity, which can be modeled under various contexts. With this in mind, we propose a new social activity-aware recruitment policy, namely Sociability-Oriented and Battery-Efficient Recruitment for Mobile Crowd-Sensing (SOBER-MCS). SOBER-MCS uses sociability and the residual power of the participant smartphones as two primary criteria in the selection of participating devices. The former is an indicator of the participant willingness toward sensing campaigns, whereas the latter is used to prioritize personal use over crowd-sensing under critical battery levels. We use sociability profiles that were obtained in our previous work and use those values to simulate the sociability behavior of a large pool of participants in an MCS environment. Through simulations, we show that SOBER-MCS is able to introduce battery savings up to 18.5% while improving user and platform utilities by 12% and 20%, respectively. PMID:29772779

SOBER-MCS: Sociability-Oriented and Battery Efficient Recruitment for Mobile Crowd-Sensing.

PubMed

Anjomshoa, Fazel; Kantarci, Burak

2018-05-17

The Internet of Things (IoT) concept is aiming at being an integral part of the next generation networking services by introducing pervasiveness and ubiquitous interconnectivity of uniquely-identifiable objects. The massive availability of personalized smart devices such as smartphones and wearables enable their penetration into the IoT ecosystem with their built-in sensors, particularly in Mobile Crowd-Sensing (MCS) campaigns. The MCS systems achieve the objectives of the large-scale non-dedicated sensing concept in the IoT if a sufficient number of participants are engaged to the collaborative data acquisition process. Therefore, user recruitment is a key challenge in MCS, which requires effective incentivization of cooperative, truthful and trustworthy users. A grand concern for the participants is the battery drain on the mobile devices. It is a known fact that battery drain in a smartphone is a function of the user activity, which can be modeled under various contexts. With this in mind, we propose a new social activity-aware recruitment policy, namely Sociability-Oriented and Battery-Efficient Recruitment for Mobile Crowd-Sensing (SOBER-MCS). SOBER-MCS uses sociability and the residual power of the participant smartphones as two primary criteria in the selection of participating devices. The former is an indicator of the participant willingness toward sensing campaigns, whereas the latter is used to prioritize personal use over crowd-sensing under critical battery levels. We use sociability profiles that were obtained in our previous work and use those values to simulate the sociability behavior of a large pool of participants in an MCS environment. Through simulations, we show that SOBER-MCS is able to introduce battery savings up to 18.5% while improving user and platform utilities by 12% and 20%, respectively.

Can Pesticide Delivery Methods Play a Role in Sustainable Pest Management?

USDA-ARS?s Scientific Manuscript database

Conventional insecticides continue to play an important role in greenhouse pest management programs. Penetrating a dense plant canopy can be difficult with a handgun, and there is some evidence that boom sprayers or broadcast applications result in a more uniform deposition than handguns. A large-...