Proliferation Risks of Fusion Energy: Clandestine Production, Covert Production, and Breakout

International Nuclear Information System (INIS)

Goldston, R.J.; Glaser, A.; Ross, A.F.

2009-01-01

Nuclear proliferation risks from fusion associated with access to weapon-usable material can be divided into three main categories: (1) clandestine production of fissile material in an undeclared facility, (2) covert production of such material in a declared and safeguarded facility, and (3) use of a declared facility in a breakout scenario, in which a state begins production of fissile material without concealing the effort. In this paper we address each of these categories of risk from fusion. For each case, we find that the proliferation risk from fusion systems can be much lower than the equivalent risk from fission systems, if commercial fusion systems are designed to accommodate appropriate safeguards

Analysis of the methods and reconstruction of iodine doses from the Chernobyl release in Belarus

International Nuclear Information System (INIS)

Lutsko, A.; Krivoruchko, K.; Gribov, A.

1997-01-01

The paper considers the method of reconstructing the iodine-131 fallout based on the systematic exposure measurements. The measurements used were taken with standard DP-5 dosimeters at the monitoring sites of the State Hydrometeorological Service network. These data have been collected since the Chernobyl NPP accident. A short-living exponent has been deduced from the exposure dose dying away. Maps of the iodine-131 release in the period of May 1 - 31, 1996 have been constructed in the attempt to estimate the doses for the initial period of the accident. The paper also dwells on the intricacy of the problem and the refinements to be made for the dose commitments with allowance for a continuing release and meteorological changes that are comparable in time with the half-life events of iodine 131 decay. A comparative analysis has been made of various methods of the dose reconstruction. The results obtained are compared with the maps of the increased incidence of the thyroid gland cancer in adults and children in Belarus. (authors) 14 refs., 2 tabs., 4 figs

Trace-Level Screening of Chemicals Related to Clandestine Desomorphine Production with Ambient Sampling, Portable Mass Spectrometry

OpenAIRE

Hall, Seth E.; O’Leary, Adam E.; Lawton, Zachary E.; Bruno, Alessandra M.; Mulligan, Christopher C.

2017-01-01

Desomorphine is a semisynthetic opioid that is responsible for the psychoactive effects of a dangerous homemade injectable mixture that goes by street name “Krokodil.” Desorption electrospray ionization (DESI) and paper spray ionization (PSI) are implemented on a portable mass spectrometer for the direct analysis of desomorphine and precursor reagent codeine from multiple substrates of potential relevance to clandestine drug laboratory synthesis and paraphernalia seizure. Minimal sample prepa...

[Attendance at a health center by clandestine prostitutes in Djibouti].

Science.gov (United States)

Philippon, M; Saada, M; Kamil, M A; Houmed, H M

1997-01-01

The extent of clandestine prostitution in Djibouti is difficult to evaluate. Due to the secrecy of the prostitutes and often their low level of education, the follow-up of these patients is also difficult. A sexually transmitted disease clinic specialized in the treatment of prostitutes and their customers has been established in Djibouti since 1963. We tried to evaluate the available data on the clandestine prostitutes attendance at the center. The population was young with a mean age of 23 years. Fifty percent had children and 60% were divorced or separated. Ninety-one percent were Ethiopian and 73% lived in the same district of the city of Djibouti. Almost half of them were HIV positive. The duration of residence in Djibouti before the first visit to the clinic varied widely with a median of 12 months. However, the total duration of prostitution before the first visit was shorter with a median of 3 months. The complaint at the first visit was most often minor. Among the prostitutes who first came to the center in 1993, half of them came only once. The overall duration of follow-up was 8 months, for an average of 3.7 visits per patient. Alternatively, 20 patients had more than 10 consultations and this represented one third of the consultations given to previous patients. This last group is the only one which tended to respect the monthly visits proposed to each patient at the first consultation. The other patients seemed to come only when they felt ill. The routine statistical activities which separately counted the new and previous patients gave an optimistic but faulty impression: these showed an increase in the total number of patients and also an increase in the percentage of previous patients visiting (from 42 to 69% between 1988 and 1994). It is difficult to evaluate the follow-up of such a mobile population. The few patients known for their fidelity contrasted with the fact that half of the patients had visited the center only once. This low frequency of

Functional Testing Differences in Anterior Cruciate Ligament Reconstruction Patients Released Versus Not Released to Return to Sport.

Science.gov (United States)

Mayer, Stephanie W; Queen, Robin M; Taylor, Dean; Moorman, Claude T; Toth, Allison P; Garrett, William E; Butler, Robert J

2015-07-01

No standardized return-to-activity or sport guidelines currently exist after anterior cruciate ligament (ACL) reconstruction. Isokinetic testing and unilateral hop testing, which have construct validity, are often used to make the determination of when a patient is ready to return to sport. Neither of these measures has been reported to be predictive of subsequent injuries. To compare the performance on 2 functional tests of ACL reconstruction patients released to return to activity versus those who have not been released based on clinical impairment measures. Cohort study; Level of evidence, 3. A total of 98 patients were examined by the treating orthopaedic surgeon 6 months after ACL reconstruction for traditional impairment measures, including swelling, range of motion, strength, and graft stability. After this examination, all subjects completed the functional testing, consisting of the Functional Movement Screen (FMS) and the Lower Quarter Y Balance Test (YBT-LQ), by an experienced tester who was blinded to the results of the clinical examination. On the basis of the clinical examination, all patients were grouped as being ready to return to sport or not being ready. Performance on the functional tests, as measured by overall performance and side-to-side asymmetry, was compared between the 2 groups using independent-samples t tests (P < .05). No difference existed between the groups with regard to the descriptive characteristics, with the exception that the group not cleared was younger (21.0 ± 7.4 years) than the group that was cleared (25.6 ± 13.2 years). Performance on the YBT-LQ revealed that no differences existed between groups when examining reach symmetry for any of the reach directions. In addition, no differences were found between groups when looking at the average reach score normalized to limb length for either the surgical or nonsurgical leg. Patients in the cleared group exhibited a similar score on the FMS (12.7 ± 2.9) compared with the

Clandestine induced abortion: prevalence, incidence and risk factors among women in a Latin American country.

Science.gov (United States)

Bernabé-Ortiz, Antonio; White, Peter J; Carcamo, Cesar P; Hughes, James P; Gonzales, Marco A; Garcia, Patricia J; Garnett, Geoff P; Holmes, King K

2009-02-03

Clandestine induced abortions are a public health problem in many developing countries where access to abortion services is legally restricted. We estimated the prevalence and incidence of, and risk factors for, clandestine induced abortions in a Latin American country. We conducted a large population-based survey of women aged 18-29 years in 20 cities in Peru. We asked questions about their history of spontaneous and induced abortions, using techniques to encourage disclosure. Of 8242 eligible women, 7992 (97.0%) agreed to participate. The prevalence of reported induced abortions was 11.6% (95% confidence interval [CI] 10.9%-12.4%) among the 7962 women who participated in the survey. It was 13.6% (95% CI 12.8%-14.5%) among the 6559 women who reported having been sexually active. The annual incidence of induced abortion was 3.1% (95% CI 2.9%-3.3%) among the women who had ever been sexually active. In the multivariable analysis, risk factors for induced abortion were higher age at the time of the survey (odds ratio [OR] 1.11, 95% CI 1.07-1.15), lower age at first sexual intercourse (OR 0.87, 95% CI 0.84-0.91), geographic region (highlands: OR 1.56, 95% CI 1.23-1.97; jungle: OR 1.81, 95% CI 1.41-2.31 [v. coastal region]), having children (OR 0.82, 95% CI 0.68-0.98), having more than 1 sexual partner in lifetime (2 partners: OR 1.61, 95% CI 1.23-2.09; > or = 3 partners: OR 2.79, 95% CI 2.12-3.67), and having 1 or more sexual partners in the year before the survey (1 partner: OR 1.36, 95% CI 1.01-1.72; > or = 2 partners: OR 1.54, 95% CI 1.14-2.02). Overall, 49.0% (95% CI 47.6%-50.3%) of the women who reported being currently sexually active were not using contraception. The incidence of clandestine, potentially unsafe induced abortion in Peru is as high as or higher than the rates in many countries where induced abortion is legal and safe. The provision of contraception and safer-sex education to those who require it needs to be greatly improved and could potentially

Reconstruction of tritium release history from contaminated groundwater using tree ring analysis

International Nuclear Information System (INIS)

Kalin, R.M.; Murphy, C.E. Jr.; Hall, G.

1995-01-01

The history of tritium releases to the groundwater from buried waste was reconstructed through dendrochronology. Wood from dated tree rings was sectioned from a cross-section of a tree that was thought to tap the groundwater. Cellulose was chemically separated from the wood. The cellulose was combusted and the water of combustion collected for liquid scintillation counting. The tritium concentration in the rings rose rapidly after 1972 which was prior to the first measurements made in this area. Trends in the tritium concentration of water outcropping to the surface are similar to the trends in tritium concentration in tree rings. 14 refs., 3 figs

Simulations of Atmospheric Krypton-85 to Assess the Detectability of Clandestine Nuclear Reprocessing

International Nuclear Information System (INIS)

Ross, O.; Ahlswede, J.; Annewandter, R.; Kalinowski, M.B.; Rast, S.; Schluenzen, K.H.

2010-01-01

The results of this study were achieved in the project 'Simulation of Atmospheric Noble Gas Concentrations to Assess Sampling Procedures for the Detection of Clandestine Nuclear Reprocessing' (IAEA GER 1643) in the joint programme of IAEA and Federal Government of Germany. In the first year of the project the detectability of additional krypton-85 sources was investigated using atmospheric transport modelling. Krypton-85 is released into the air during reprocessing of spent nuclear fuel rods. Therefore the krypton-85 signature can possibly be used for the detection of undeclared plutonium separation. First, the global krypton-85 background produced by known reprocessing facilities from 1971 until 2006 was simulated with the atmospheric general circulation model ECHAM5 using annual emission data. The model results were evaluated by extensive comparison with measurements performed by the German Federal Office for Radiation Protection. Of particular interest for an assessment of the detectability of unknown sources is the background variability. The variability of concentrations is very high over central Europe, where the large reprocessing plants La Hague and Sellafield are located, and it is very low on the Southern Hemisphere, where no nuclear reprocessing takes place. The analysis of concentration time series on various time scales allows partly a distinction between fluctuations caused by the variability of the sources from variations due to atmospheric dynamics. Furthermore the detection sensitivity to a set of arbitrarily specified source locations is analysed with a Lagrangian particle dispersion model. This, in combination with the location specific background variability, is giving first benchmarks on the capability of using krypton-85 for IAEA Safeguards based on the Additional Protocols foreseeing environmental sampling. (author)

Hanford environmental dose reconstruction project - an overview

International Nuclear Information System (INIS)

Shipler, D.B.; Napier, B.A.; Farris, W.T.

1996-01-01

The Hanford Environmental Dose Reconstruction Project was initiated because of public interest in the historical releases of radioactive materials from the Hanford Site, located in southcentral Washington State. By 1986, over 38,000 pages of environmental monitoring documentation from the early years of Hanford operations had been released. Special committees reviewing the documents recommended initiation of the Hanford Environmental Dose Reconstruction Project, which began in October 1987, and is conducted by Battelle, Pacific Northwest Laboratories. The technical approach taken was to reconstruct releases of radioactive materials based on facility operating information; develop and/or adapt transport, pathway, and dose models and computer codes; reconstruct environmental, meterological, and hydrological monitoring information; reconstruct demographic, agricultural, and lifestyle characteristics; apply statistical methods to all forms of uncertainty in the information, parameters, and models; and perform scientific investigation that were technically defensible. The geographic area for the study includes ∼2 x 10 5 km 2 (75,000 mi 2 ) in eastern Washington, western Idaho, and northeastern Oregon (essentially the Mid-columbia Basin of the Pacific Northwest). Three exposure pathways were considered: the atmosphere, the Columbia River, and ground water

LATOUCHE, Serge. Cornelius Castoriadis ou l’autonomie radical. Colección: Les précurseurs de la décoissance. Neuvy-en-Champagne. Le passager Clandestin. ISBN: 978-2-36935-008-8.

Directory of Open Access Journals (Sweden)

EMILIANO ALDEGANI

2015-06-01

Full Text Available LATOUCHE, Serge. Cornelius Castoriadis ou l’autonomie radical.Colección: Les précurseurs de la décoissance. Neuvy-en-Champagne. Le passager Clandestin. ISBN: 978-2-36935-008-8.

Trace-Level Screening of Chemicals Related to Clandestine Desomorphine Production with Ambient Sampling, Portable Mass Spectrometry

Directory of Open Access Journals (Sweden)

Seth E. Hall

2017-01-01

Full Text Available Desomorphine is a semisynthetic opioid that is responsible for the psychoactive effects of a dangerous homemade injectable mixture that goes by street name “Krokodil.” Desorption electrospray ionization (DESI and paper spray ionization (PSI are implemented on a portable mass spectrometer for the direct analysis of desomorphine and precursor reagent codeine from multiple substrates of potential relevance to clandestine drug laboratory synthesis and paraphernalia seizure. Minimal sample preparation required for analysis and portability of the instrument suggest the potential for rapid, on-site analysis of evidence, a highly desired benefit for forensic science and law enforcement practitioners. Both DESI-MS and PSI-MS can generate spectra consistent with preceding data obtained using traditional ionization methods, while demonstrating detection limits in the low- to sub-ng levels.

Reconstruction of the contamination of the Techa River in 1949-1951 as a result of releases from the ''MAYAK'' Production Association

International Nuclear Information System (INIS)

Shagina, N.B.; Vorobiova, M.I.; Degteva, M.O.; Peremyslova, L.M.; Shishkina, E.A.; Anspaugh, L.R.; Napier, B.A.

2012-01-01

More accurate reconstruction of the radioactive contamination of the Techa River system in 1949-1951 has been made on the basis of refined data on the amounts and the rate of discharge of radionuclides into the Techa River from the Mayak Production Association; this has led to the development of a modified Techa River model that describes the transport of radionuclides through the up-river ponds and along the Techa River and deposition of radionuclides in the river-bottom sediments and flooded areas. The refined Techa River source-term data define more precisely the time-dependent rates of release and radionuclide composition of the releases that occurred during 1949-1951. The Techa River model takes into account the time-dependent characteristics of the releases and considers (a) the transport of radionuclides adsorbed on solid particles originally contained in the discharges or originating in the up-river ponds as a result of stirring up of contaminated bottom sediments and (b) the transport of radionuclides in soluble form. The output of the Techa River model provides concentrations of all source-term radionuclides in the river water, bottom sediments, and floodplain soils at different distances from the site of radioactive releases for the period of major contamination in 1950-1951. The outputs of the model show good agreement with historical measurements of water and sediment contamination. In addition, the river-model output for 90 Sr concentration in the river water is harmonized with retrospective estimates derived from the measurements of 90 Sr in the residents of the Techa Riverside villages. Modeled contamination of the floodplain soils by 137 Cs is shown to be in agreement with the values reconstructed from late measurements of this radionuclide. Reconstructed estimates of the Techa River contamination are being used for the quantification of internal and external doses received by residents of the Techa Riverside communities. (orig.)

Characterisation of aqueous waste produced during the clandestine production of amphetamine following the Leuckart route utilising solid-phase extraction gas chromatography-mass spectrometry and capillary electrophoresis with contactless conductivity detection.

Science.gov (United States)

Hauser, Frank M; Hulshof, Janneke W; Rößler, Thorsten; Zimmermann, Ralf; Pütz, Michael

2018-04-18

Chemical waste from the clandestine production of amphetamine is of forensic and environmental importance due to its illegal nature which often leads to dumping into the environment. In this study, 27 aqueous amphetamine waste samples from controlled Leuckart reactions performed in Germany, the Netherlands, and Poland were characterised to increase knowledge about the chemical composition and physicochemical characteristics of such waste. Aqueous waste samples from different reaction steps were analysed to determine characteristic patterns which could be used for classification. Conductivity, pH, density, ionic load, and organic compounds were determined using different analytical methods. Conductivity values ranged from 1 to over 200 mS/cm, pH values from 0 to 14, and densities from 1.0 to 1.3 g/cm 3 . A capillary electrophoresis method with contactless conductivity detection (CE-C 4 D) was developed and validated to quantify chloride, sulphate, formate, ammonium, and sodium ions which were the most abundant ions in the investigated waste samples. A solid-phase extraction sample preparation was used prior to gas chromatography-mass spectrometry analysis to determine the organic compounds. Using the characterisation data of the known samples, it was possible to assign 16 seized clandestine waste samples from an amphetamine production to the corresponding synthesis step. The data also allowed us to draw conclusions about the synthesis procedure and used chemicals. The presented data and methods could support forensic investigations by showing the probative value of synthesis waste when investigating the illegal production of amphetamine. It can also act as starting point to develop new approaches to tackle the problem of clandestine waste dumping. Copyright © 2018 John Wiley & Sons, Ltd.

Reconstruction of the contamination of the Techa River in 1949-1951 as a result of releases from the ''MAYAK'' Production Association

Energy Technology Data Exchange (ETDEWEB)

Shagina, N.B.; Vorobiova, M.I.; Degteva, M.O.; Peremyslova, L.M.; Shishkina, E.A. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Anspaugh, L.R. [University of Utah, Salt Lake City, UT (United States); Napier, B.A. [Pacific Northwest National Laboratory, Richland, WA (United States)

2012-11-15

More accurate reconstruction of the radioactive contamination of the Techa River system in 1949-1951 has been made on the basis of refined data on the amounts and the rate of discharge of radionuclides into the Techa River from the Mayak Production Association; this has led to the development of a modified Techa River model that describes the transport of radionuclides through the up-river ponds and along the Techa River and deposition of radionuclides in the river-bottom sediments and flooded areas. The refined Techa River source-term data define more precisely the time-dependent rates of release and radionuclide composition of the releases that occurred during 1949-1951. The Techa River model takes into account the time-dependent characteristics of the releases and considers (a) the transport of radionuclides adsorbed on solid particles originally contained in the discharges or originating in the up-river ponds as a result of stirring up of contaminated bottom sediments and (b) the transport of radionuclides in soluble form. The output of the Techa River model provides concentrations of all source-term radionuclides in the river water, bottom sediments, and floodplain soils at different distances from the site of radioactive releases for the period of major contamination in 1950-1951. The outputs of the model show good agreement with historical measurements of water and sediment contamination. In addition, the river-model output for {sup 90}Sr concentration in the river water is harmonized with retrospective estimates derived from the measurements of {sup 90}Sr in the residents of the Techa Riverside villages. Modeled contamination of the floodplain soils by {sup 137}Cs is shown to be in agreement with the values reconstructed from late measurements of this radionuclide. Reconstructed estimates of the Techa River contamination are being used for the quantification of internal and external doses received by residents of the Techa Riverside communities. (orig.)

Patterns of resistance and transgression in Eastern Indonesia: single women's practices of clandestine courtship and cohabitation.

Science.gov (United States)

Bennett, Linda Rae

2005-03-01

This paper explores how single women in the regional Indonesian city of Mataram express sexual desire in a social, cultural and political climate that idealizes the confinement of female sexuality within marriage. It is based on 21 months of ethnographic fieldwork conducted with single women, their families and health care providers. Success for young women in negotiating sexual desire is dependent upon their ability to maintain a faultless public reputation and mediate between their desires and those of men. Many single women find ways to pursue their desires by bending the rules of courtship conventions, performing sexual purity in public, while resisting from within the hegemonic sexual culture. However, women who visibly transgress dominant sexual ideals (and in doing so offend the status quo) are stigmatized and ostracized. Single women's practice of resistance and sexual transgression in premarital relationships are represented using the examples of pacaran backstreet (clandestine courtship) and cohabitation prior to marriage.

Local delivery of controlled-release simvastatin to improve the biocompatibility of polyethylene terephthalate artificial ligaments for reconstruction of the anterior cruciate ligament

Directory of Open Access Journals (Sweden)

Zhang P

2016-01-01

-sustained release from SIM/COL/PET promoted the graft–bone healing via its effect on both angiogenesis and osteogenesis. This study suggested that collagen containing low-dose SIM microsphere coating on the surface of PET artificial ligaments could be potentially applied for ACL reconstruction. Keywords: simvastatin, controlled release, graft–bone healing, biocompatibility, ligament reconstruction

La migration clandestine mexicaine comme un crime : commentaires sur quelques effets de la loi SB. 1070 de l’État de l’Arizona

Directory of Open Access Journals (Sweden)

Philippe Schaffhauser

2011-11-01

Full Text Available Cet article a pour objectif d’analyser les effets réels et possibles de l’entrée en vigueur en 2010 de la loi SB 1070, dite loi Arizona, laquelle se présente comme un dispositif juridique visant à lutter contre la migration clandestine dans cette partie de l’Union Américaine. Or cette loi a pour première conséquence pratique de criminaliser un type de situation migratoire et de stigmatiser ensuite la population mexicaine qui, selon les représentations sociales xénophobes, incarne para « excellence » (i.e. délit de facies, la figure du clandestin aux États-Unis. Être mexicain, dans ce pays, finit par être le commencement d’un délit ou du moins jette un doute sur la situation migratoire de l’ensemble des ressortissants de cette communauté nationale. L’article s’emploie à montrer l’arbitraire (l’État de l’Arizona comme tous les autres États de l’Union n’est pas compétent en matière de migration et la construction artificielle du délit imputé aux sans papiers. En effet, faire de la migration clandestine un crime pose le problème objectif de déterminer qui est la victime réelle d’un tel acte et, selon l’expression consacrée par John Stuart Mill, cette forme de migration apparaît au regard de la philosophie morale comme « crime sans victimes », puisque la seule victime de cette infraction à la loi c’est la société américaine toute entière, ses lois, ses normes, ses valeurs et ses institutions, soit une entité abstraite au regard de ce qui se joue au quotidien en matière migration clandestine et de contrôle policier.This article aims to examine the real effects and possible entry into force in 2010 of the so-called law SB 1070 Arizona law, which presents itself as a legal device to combat against illegal migration in this part of the American Union. However this Act is to first practical consequence criminalize a type of migratory situation and then condemn the Mexican population

Examination of the potential for diversion or clandestine dual use of a pebble-bed reactor to produce plutonium

International Nuclear Information System (INIS)

Ougouag, A.M.; Terry, W.K.; Gougar, H.D.

2002-01-01

This paper explores the susceptibility of Pebble-Bed Reactors (PBRs) to be used overtly or covertly for the production of plutonium for nuclear weapons. The basic assumption made for the consideration of overt production is that a country would purchase a PBR with the ostensible motive of producing electric power; then, after the power plant was built, the country would divert the facility entirely to the production of weapons material. It is assumed that the country would then have to manufacture production pebbles from natural uranium. The basic assumption made for covert production is that the country would obtain and use a PBR for power production, but that it would clandestinely feed plutonium production pebbles through the reactor in such small numbers that the perturbation on power plant operation would be very difficult to detect. This paper shows the potential rate of plutonium production under such constraints. It is demonstrated that the PBR is a very poor choice for either form of proliferation-intent use. (author)

Fate of 1-(1′,4′-cyclohexadienyl)-2-methylaminopropane (CMP) in soil: Route-specific by-product in the clandestine manufacture of methamphetamine

International Nuclear Information System (INIS)

Pal, Raktim; Megharaj, Mallavarapu; Kirkbride, K. Paul; Naidu, Ravi

2012-01-01

We investigated the fate of 1-(1′,4′-cyclohexadienyl)-2-methylaminopropane (CMP) in soil. CMP is the major route-specific byproduct in the clandestine manufacture of methamphetamine (MAP) by the use of excess alkali metal (e.g., lithium) in liquid ammonia, which is commonly referred to as the “Nazi method”. This is one of the most common methods used in many countries for the illicit production of MAP. Knowledge on the fate of CMP in the terrestrial environment is essential to combat potential threats arising from illegal dumping of clandestine laboratory wastes. We report on the sorption–desorption, degradation, and metabolism patterns of CMP in three South Australian soils investigated in laboratory scale. CMP sorption in the test soils followed a Freundlich isotherm in the concentration range of 5 to 100 μg mL −1 . Degradation studies showed that CMP was fairly unstable in both non-sterile and sterile soils, with half-life values typically less than one week. The role of biotic and abiotic soil processes in the degradation of CMP also varied significantly between the different soils, and with the length of the incubation period. Interestingly, but not surprisingly, the results showed that the CMP was not actually degraded to any simpler compounds but transformed to more persistent MAP. Thus, the main concern with Nazi method is the potential hazard from MAP rather than CMP if wastes are disposed of into the environment. - Highlights: ► This study investigated the fate of 1-(1′,4′-cyclohexadienyl)-2-methylaminopropane (CMP) in soils. ► CMP was fairly unstable in both non-sterile and sterile soils, with half-life values less than a week. ► CMP transforms to more persistent methylamphetamine (MAP) in soils which is a major environmental concern.

Fate of 1-(1 Prime ,4 Prime -cyclohexadienyl)-2-methylaminopropane (CMP) in soil: Route-specific by-product in the clandestine manufacture of methamphetamine

Energy Technology Data Exchange (ETDEWEB)

Pal, Raktim [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, Adelaide, South Australia, Australia-5095 and CRC for Contamination Assessment and Remediation of the Environment, University of South Australia (Australia); Megharaj, Mallavarapu, E-mail: Megharaj.Mallavarapu@unisa.edu.au [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, Adelaide, South Australia, Australia-5095 and CRC for Contamination Assessment and Remediation of the Environment, University of South Australia (Australia); Kirkbride, K. Paul [Australian Federal Police Forensic and Data Centres, Canberra (Australia); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, Adelaide, South Australia, Australia-5095 and CRC for Contamination Assessment and Remediation of the Environment, University of South Australia (Australia)

2012-02-01

We investigated the fate of 1-(1 Prime ,4 Prime -cyclohexadienyl)-2-methylaminopropane (CMP) in soil. CMP is the major route-specific byproduct in the clandestine manufacture of methamphetamine (MAP) by the use of excess alkali metal (e.g., lithium) in liquid ammonia, which is commonly referred to as the 'Nazi method'. This is one of the most common methods used in many countries for the illicit production of MAP. Knowledge on the fate of CMP in the terrestrial environment is essential to combat potential threats arising from illegal dumping of clandestine laboratory wastes. We report on the sorption-desorption, degradation, and metabolism patterns of CMP in three South Australian soils investigated in laboratory scale. CMP sorption in the test soils followed a Freundlich isotherm in the concentration range of 5 to 100 {mu}g mL{sup -1}. Degradation studies showed that CMP was fairly unstable in both non-sterile and sterile soils, with half-life values typically less than one week. The role of biotic and abiotic soil processes in the degradation of CMP also varied significantly between the different soils, and with the length of the incubation period. Interestingly, but not surprisingly, the results showed that the CMP was not actually degraded to any simpler compounds but transformed to more persistent MAP. Thus, the main concern with Nazi method is the potential hazard from MAP rather than CMP if wastes are disposed of into the environment. - Highlights: Black-Right-Pointing-Pointer This study investigated the fate of 1-(1 Prime ,4 Prime -cyclohexadienyl)-2-methylaminopropane (CMP) in soils. Black-Right-Pointing-Pointer CMP was fairly unstable in both non-sterile and sterile soils, with half-life values less than a week. Black-Right-Pointing-Pointer CMP transforms to more persistent methylamphetamine (MAP) in soils which is a major environmental concern.

Communication tools for the Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Blazek, Mary Lou; Power, Max S.

1992-01-01

From 1944 to 1989, the U.S. Department of Energy produced plutonium at the Hanford Site in southeast Washington State. In the early days of operation, large amounts of radioactive materials were released to the environment. Documents about the releases were made public in 1986. The Hanford Environmental Dose Reconstruction Project began in 1987. The Project will determine how much radioactive material was released, how that material may have exposed people, and what radiation doses people may have received. The Project will be complete in 1995. The federal government pays for the work. The scientific work on the study is done by Battelle's Pacific Northwest Laboratory. Public credibility and valid science are equally important to those directing the dose reconstruction work. A number of tools are used to inform the public and encourage public participation. These tools are examined in this paper. (author)

Savannah River Site radioiodine atmospheric releases and offsite maximum doses

International Nuclear Information System (INIS)

Marter, W.L.

1990-01-01

Radioisotopes of iodine have been released to the atmosphere from the Savannah River Site since 1955. The releases, mostly from the 200-F and 200-H Chemical Separations areas, consist of the isotopes, I-129 and 1-131. Small amounts of 1-131 and 1-133 have also been released from reactor facilities and the Savannah River Laboratory. This reference memorandum was issued to summarize our current knowledge of releases of radioiodines and resultant maximum offsite doses. This memorandum supplements the reference memorandum by providing more detailed supporting technical information. Doses reported in this memorandum from consumption of the milk containing the highest I-131 concentration following the 1961 1-131 release incident are about 1% higher than reported in the reference memorandum. This is the result of using unrounded 1-131 concentrations of I-131 in milk in this memo. It is emphasized here that this technical report does not constitute a dose reconstruction in the same sense as the dose reconstruction effort currently underway at Hanford. This report uses existing published data for radioiodine releases and existing transport and dosimetry models

Iodine-131 releases from the Hanford Site, 1944--1947

International Nuclear Information System (INIS)

Heeb, C.M.

1992-10-01

Detailed results of the Hanford Environmental Dose Reconstruction (HEDR) iodine-131 release reconstruction are presented in this volume. Included are daily data on B, D, and F Plant, reactor operations from the P-Department Daily Reports (General Electric Company 1947). Tables of B and T Plant material processed from the three principal sources on separations plant operations: The Jaech report (Jaech undated), the 200 Area Report (Acken and Bird 1945; Bird and Donihee 1945), and the Metal History Reports (General Electric Company 1946). A transcription of the Jaech report is also provided because it is computer-generated and is not readily readable in its original format. The iodine-131 release data are from the STRM model. Cut-by-cut release estimates are provided, along with daily, monthly, and yearly summations. These summations are based on the hourly release estimates. The hourly data are contained in a 28 megabyte electronic file. Interested individuals may request a copy

Visible Fists, Clandestine Kicks, and Invisible Elbows: Three Forms of Regulating Neoliberal Poverty

Directory of Open Access Journals (Sweden)

Javier Auyero

2010-10-01

Full Text Available Argentina In a preliminary attempt to understand the daily production of poor people’s subordination in contemporary Argentina, this paper explores the workings of overt and covert forms of state violence against the urban destitute and of more subtle modes of domination. Attention to the simultaneous operation of what this paper calls visible fists, clandestine kicks, and invisible elbows in the daily life of the dispossessed serves to a better integrate violence into the study of popular politics, and b cast light on the productive (and not merely repressive nature of state power.   Resumen: Puños visibles, patadas clandestinas y codos invisibles: tres formas de regulación de la pobreza neoliberal En un acercamiento preliminar a la producción cotidiana de la subordinación de los pobres urbanos en la Argentina contemporánea, este artículo explora las formas abiertas y encubiertas de violencia estatal contra los más destituidos y las modalidades más sutiles de dominación. Una atención simultánea a lo que el artículo denomina puños visibles, patadas clandestinas, y codos invisibles en la vida cotidiana de los desposeídos es útil a los efectos de: a integrar la violencia en el estudio de la política popular, y b iluminar la naturaleza productiva (y no meramente represiva del poder estatal.

Trochleoplasty and medial patellofemoral ligament reconstruction for recurrent patellar dislocation

Directory of Open Access Journals (Sweden)

K Raghuveer Reddy

2012-01-01

Full Text Available We report a case of recurrent patellar dislocation with high-grade trochlear dysplasia which persisted despite two previous operations. We did a Dejour′s sulcus deepening trochleoplasty, medial patellofemoral ligament reconstruction, and lateral retinacular release. Trochleoplasty and medial patellofemoral ligament reconstruction is required in patients with high grade trochlear dysplasia.

Improving tritium exposure reconstructions using accelerator mass spectrometry

International Nuclear Information System (INIS)

Love, A.H.; Hunt, J.R.; Vogel, J.S.; Knezovich, J.P.

2004-01-01

Direct measurement of tritium atoms by accelerator mass spectrometry (AMS) enables rapid low-activity tritium measurements from milligram-sized samples and permits greater ease of sample collection, faster throughput, and increased spatial and/or temporal resolution. Because existing methodologies for quantifying tritium have some significant limitations, the development of tritium AMS has allowed improvements in reconstructing tritium exposure concentrations from environmental measurements and provides an important additional tool in assessing the temporal and spatial distribution of chronic exposure. Tritium exposure reconstructions using AMS were previously demonstrated for a tree growing on known levels of tritiated water and for trees exposed to atmospheric releases of tritiated water vapor. In these analyses, tritium levels were measured from milligram-sized samples with sample preparation times of a few days. Hundreds of samples were analyzed within a few months of sample collection and resulted in the reconstruction of spatial and temporal exposure from tritium releases. Although the current quantification limit of tritium AMS is not adequate to determine natural environmental variations in tritium concentrations, it is expected to be sufficient for studies assessing possible health effects from chronic environmental tritium exposure. (orig.)

Improving tritium exposure reconstructions using accelerator mass spectrometry

Science.gov (United States)

Hunt, J. R.; Vogel, J. S.; Knezovich, J. P.

2010-01-01

Direct measurement of tritium atoms by accelerator mass spectrometry (AMS) enables rapid low-activity tritium measurements from milligram-sized samples and permits greater ease of sample collection, faster throughput, and increased spatial and/or temporal resolution. Because existing methodologies for quantifying tritium have some significant limitations, the development of tritium AMS has allowed improvements in reconstructing tritium exposure concentrations from environmental measurements and provides an important additional tool in assessing the temporal and spatial distribution of chronic exposure. Tritium exposure reconstructions using AMS were previously demonstrated for a tree growing on known levels of tritiated water and for trees exposed to atmospheric releases of tritiated water vapor. In these analyses, tritium levels were measured from milligram-sized samples with sample preparation times of a few days. Hundreds of samples were analyzed within a few months of sample collection and resulted in the reconstruction of spatial and temporal exposure from tritium releases. Although the current quantification limit of tritium AMS is not adequate to determine natural environmental variations in tritium concentrations, it is expected to be sufficient for studies assessing possible health effects from chronic environmental tritium exposure. PMID:14735274

Benchmarking Close-range Structure from Motion 3D Reconstruction Software under Varying Capturing Conditions

DEFF Research Database (Denmark)

Nikolov, Ivan Adriyanov; Madsen, Claus B.

2016-01-01

Structure from Motion 3D reconstruction has become widely used in recent years in a number of fields such as industrial surface in- inspection, archeology, cultural heritage preservation and geomapping. A number of software solutions have been released using variations of this technique. In this ......Structure from Motion 3D reconstruction has become widely used in recent years in a number of fields such as industrial surface in- inspection, archeology, cultural heritage preservation and geomapping. A number of software solutions have been released using variations of this technique...

Position reconstruction in LUX

Science.gov (United States)

Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.

2018-02-01

The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe the response of the PMTs. The reconstruction was assessed with calibration data including 83mKr (releasing a total energy of 41.5 keV) and 3H (β- with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV) . Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of σ = 0.82 cm and σ = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies ~0.25 keV and ~10 keV, respectively. The reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.

Dietary supplements: International legal framework and adulteration profiles, and characteristics of products on the Brazilian clandestine market.

Science.gov (United States)

da Justa Neves, Diana Brito; Caldas, Eloisa Dutra

2015-10-01

The objectives of this work were to evaluate current legislation on dietary supplements in the United States, the European Union and Brazil, and the profile of adulterated and/or irregular products on these markets. Due to a less restrictive legal framework, a supplement product that is freely available in the US may be considered a drug or even be proscribed in the EU and Brazil, thus giving rise to a clandestine market based on smuggling. From 2007 to 2014, the United States Food and Drug Administration reported 572 cases of supplement adulterations in the country, mainly products for sexual enhancement (41.6%). Data from the European Union Rapid Alert System for Food and Feed showed 929 adulterations during the same period, over 40% due to unauthorized ingredients or undeclared medicines. From 2007 to 2013, the Brazilian Federal Police Department seized 5470 supplement products, 92.2% with an American-declared origin. Qualitative chemical analyses performed on 2898 products found 180 adulterations, 41.1% due to undeclared drugs, mainly anabolic steroids, anorectics and products for erectile dysfunction, all considered medicines in Brazil. Educating the public regarding the potential risks they are taking when consuming adulterated or irregular products is necessary to protect the health of consumers. Copyright © 2015 Elsevier Inc. All rights reserved.

On-site inspection: A brief overview and bibliography of techniques pertinent to assessing suspected nuclear test sites

International Nuclear Information System (INIS)

Carrigan, C.R.

1993-03-01

The purpose of this report is to provide a brief overview and bibliography of those techniques that may have application for the evaluation of a site to determine if a high energy release event is nuclear in nature. This effort is motivated by recognition of the changing world political climate and the perception that low yield and non-proliferation issues will grow in importance as countries become increasingly involved as signators to treaties that are intended to limit the development and testing of nuclear weapons. Along with an increasing interest in such issues is the awareness of the need to implement improved capabilities for treaty monitoring programs that must deal with assessing suspicious occurrences of high energy release events. In preparing this report, it is recognized that monitoring can take two main forms. The first involves the resolution of unidentified events detected by seismic and satellite National Technical Means. Events of an indeterminate nature could occur world-wide and could induce tension in neighboring countries. If an on-site measurement capability were available, a monitoring team could be sent to the suspected site of an event to take measurements that could confirm or disprove the occurrence of a clandestine nuclear test. The second monitoring form is the confirmation that a clandestine event is not masked by a declared event. For example, a large mining explosion could mask a decoupled nuclear explosion. On-site measurements before and during the test could confirm that a clandestine event did not occur and could provide assurance that the party carrying out the explosion is not taking advantage of clandestine testing opportunities. 48 refs

Oak Ridge Dose Reconstruction Project Summary Report; Reports of the Oak Ridge Dose Reconstruction, Vol. 7

International Nuclear Information System (INIS)

Widner, Thomas E.; email = twidner@jajoneses.com

1999-01-01

In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel of individuals appointed by Tennessee's Commissioner of Health. The panel requested that the principal investigator for the project prepare the following report, ''Oak Ridge Dose Reconstruction Project Summary Report,'' to serve the following purposes: (1) summarize in a single, less technical report, the methods and results of the various investigations that comprised the Phase II of the dose reconstruction; (2) describe the systematic searching of classified and unclassified historical records that was a vital component of the project; and (3) summarize the less detailed, screening-level assessments that were performed to evaluate the potential health significance of a number of materials, such a uranium, whose priority did not require a complete dose reconstruction effort. This report describes each major step of the dose reconstruction study: (1) the review of thousands of historical records to obtain information relating to past operations at each facility; (2) estimation of the quantity and timing of releases of radioiodines from X-10, of mercury from Y-12, of PCB's from all facilities, and of cesium-137 and other radionuclides from White Oak Creek; (3) evaluation of the routes taken by these contaminants through the environment to nearby populations; and (4) estimation of doses and health risks to exposed groups. Calculations found the highest excess cancer risks for a female born in 1952 who drank goat milk; the highest non-cancer health risk was for children in a farm family exposed to PCBs in and near East Fork Poplar Creek. More detailed

Validation of software releases for CMS

International Nuclear Information System (INIS)

Gutsche, Oliver

2010-01-01

The CMS software stack currently consists of more than 2 Million lines of code developed by over 250 authors with a new version being released every week. CMS has setup a validation process for quality assurance which enables the developers to compare the performance of a release to previous releases and references. The validation process provides the developers with reconstructed datasets of real data and MC samples. The samples span the whole range of detector effects and important physics signatures to benchmark the performance of the software. They are used to investigate interdependency effects of all CMS software components and to find and fix bugs. The release validation process described here is an integral part of CMS software development and contributes significantly to ensure stable production and analysis. It represents a sizable contribution to the overall MC production of CMS. Its success emphasizes the importance of a streamlined release validation process for projects with a large code basis and significant number of developers and can function as a model for future projects.

Reconstruction of deformities resulting from penile enlargement surgery.

Science.gov (United States)

Alter, G J

1997-12-01

More than 30 patients presented for reconstruction of penile deformities secondary to penile enlargement surgery performed by other physicians. Lengthening was performed by releasing the suspensory ligament of the penis and advancing pubic skin with a V-Y advancement flap. Girth was increased by injecting autologous fat. Specific complaints relating to the lengthening procedure involve hypertrophic and/or wide scars, a proximal penile hump from a thick, hair-bearing V-Y flap, and a low hanging penis. Complications relating to autologous fat injections include disappearance of fat, penile lumps and nodules, and shaft deformities. The repair of these deformities is described. From 1994 through October 1996, 19 men underwent 24 various combinations of reconstructive operations, such as scar revisions, V-Y advancement flap reversal, and removal of fat nodules and asymmetrical fat deposits. Penile appearance and function were improved. Complications include 1 hematoma requiring drainage, minor wound complications and 1 inadequately reversed V-Y flap. The methods of various repairs are discussed, including reconstructive limitations, timing and staging. Significant improvement can be achieved with proper reconstruction of penile deformities.

Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Cannon, S.D.; Finch, S.M.

1992-10-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates

Hanford Environmental Dose Reconstruction Project independent direction and oversight

International Nuclear Information System (INIS)

Blazek, M.L.; Power, M.

1991-01-01

Hanford was selected in 1942 as one of the sites for the Manhattan Project. It produced plutonium for one of the world's first nuclear weapons. The US Department of Energy (DOE) and its predecessors continued to make plutonium for nuclear weapons at Hanford for more than four decades. In the early days of Hanford operations, radioactive materials routinely were released to the environment by many processes. The DOE disclosed documents about these releases in 1986. In 1987, Washington, Oregon, and regional Indian tribes gathered an independent panel of experts. This group recommended dose reconstruction and health effects feasibility studies. Later that year, DOE hired Battelle Pacific Northwest Laboratory (PNL) to reconstruct potential public radiation doses from Hanford's past releases of radioactive material. The DOE agreed with the states and tribes that project direction would come from an independent technical steering panel (TSP). This approach was critical to gain public credibility for the project and the science. The TSP directs the project and makes policy. That is now clear - but, it was hard-earned. Conducting science in an open public process is new, challenging, and clearly worthwhile. The panel's product is good science that is believed and accepted by the public - our client

Oak Ridge Dose Reconstruction Project Summary Report; Reports of the Oak Ridge Dose Reconstruction, Vol. 7

Energy Technology Data Exchange (ETDEWEB)

Thomas E. Widner; et. al.

1999-07-01

In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel of individuals appointed by Tennessee's Commissioner of Health. The panel requested that the principal investigator for the project prepare the following report, ''Oak Ridge Dose Reconstruction Project Summary Report,'' to serve the following purposes: (1) summarize in a single, less technical report, the methods and results of the various investigations that comprised the Phase II of the dose reconstruction; (2) describe the systematic searching of classified and unclassified historical records that was a vital component of the project; and (3) summarize the less detailed, screening-level assessments that were performed to evaluate the potential health significance of a number of materials, such a uranium, whose priority did not require a complete dose reconstruction effort. This report describes each major step of the dose reconstruction study: (1) the review of thousands of historical records to obtain information relating to past operations at each facility; (2) estimation of the quantity and timing of releases of radioiodines from X-10, of mercury from Y-12, of PCB's from all facilities, and of cesium-137 and other radionuclides from White Oak Creek; (3) evaluation of the routes taken by these contaminants through the environment to nearby populations; and (4) estimation of doses and health risks to exposed groups. Calculations found the highest excess cancer risks for a female born in 1952 who drank goat milk; the highest non-cancer health risk was for children in a farm family exposed to PCBs in and near

SYRMEP Tomo Project: a graphical user interface for customizing CT reconstruction workflows.

Science.gov (United States)

Brun, Francesco; Massimi, Lorenzo; Fratini, Michela; Dreossi, Diego; Billé, Fulvio; Accardo, Agostino; Pugliese, Roberto; Cedola, Alessia

2017-01-01

When considering the acquisition of experimental synchrotron radiation (SR) X-ray CT data, the reconstruction workflow cannot be limited to the essential computational steps of flat fielding and filtered back projection (FBP). More refined image processing is often required, usually to compensate artifacts and enhance the quality of the reconstructed images. In principle, it would be desirable to optimize the reconstruction workflow at the facility during the experiment (beamtime). However, several practical factors affect the image reconstruction part of the experiment and users are likely to conclude the beamtime with sub-optimal reconstructed images. Through an example of application, this article presents SYRMEP Tomo Project (STP), an open-source software tool conceived to let users design custom CT reconstruction workflows. STP has been designed for post-beamtime (off-line use) and for a new reconstruction of past archived data at user's home institution where simple computing resources are available. Releases of the software can be downloaded at the Elettra Scientific Computing group GitHub repository https://github.com/ElettraSciComp/STP-Gui.

Detection of cold gas releases in space via low energy neutral atom imaging

International Nuclear Information System (INIS)

McComas, D.J.; Funsten, H.O.; Moore, K.R.; Scime, E.E.; Thomsen, M.F.

1993-01-01

Low energy neutral atoms (LENAs) are produced in space plasmas by charge exchange between the ambient magnetospheric plasma ions and cold neutral atoms. Under normal conditions these cold neutrals come from the terrestrial geocorona, a shroud of few-eV hydrogen atoms surrounding the Earth. As a consequence of this charge exchange, it has become possible to remotely image many regions of the magnetosphere for the first time utilizing recently developed LENA imaging technology. In addition to the natural hydrogen geocorona, conventional explosions and maneuvering thruster firings can also introduce large amounts of cold gas into the space environment. In this paper the authors examine whether such potentially clandestine activities could also be remotely observed for the first time via LENA imaging. First, they examine the fluxes of LENAs produced in the space environment from a conventional explosion. Then they review the present state of the art in the emerging field of LENA detection and imaging. Recent work has shown that LENAs can be imaged by first converting the neutrals to ions with ultra-thin (10s of angstrom) foils and then electrostatically analyzing these newly created ions to reject the large (> 10 10 cm -2 s -1 ) UV background to which the low energy detectors are sensitive. They conclude that the sensitivities for present LENA imager designs may be just adequate for detecting some man-made releases. With additional improvements in LENA detection capabilities, this technique could become an important new method for monitoring for conventional explosions, as well as other man-made neutral releases, in the space environment

Effect of drug precursors and chemicals relevant to clandestine laboratory investigation on plastic bags used for collection and storage.

Science.gov (United States)

Michelot, Harmonie; Fu, Shanlin; Stuart, Barbara; Shimmon, Ronald; Raymond, Tony; Crandell, Tony; Roux, Claude

2017-04-01

In the area of clandestine laboratory investigations, plastic bags are used to collect and store evidence, such as solvents, precursors, and other compounds usually employed for the manufacturing of drugs (although liquids may be stored in glass containers within the bags first). In this study, three different types of plastic bags were provided by the NSW Police Force and investigated for their suitability for evidence collection: two different types of low-density polyethylene (LDPE) bags and one type of polyvinyl chloride (PVC) bag. Three different experiments were carried out: (1) storing relevant chemicals in the bags for up to three months; (2) exposing the bags including their content to accelerated conditions using a weatherometer, and (3) simulating an expected real case scenario. This study indicates that drugs and related chemicals stored in plastic bags may lead to a change in the composition of the chemical and an alteration or degradation of the plastic bag. All experiments led to the same conclusion: the polyvinyl chloride bags appeared to be the most affected. LDPE bags seem to be more appropriate for routine use, although it has been established they are not suitable for the collection of liquids (unless pre-packaged in, for instance, a glass container). Copyright © 2017 Elsevier B.V. All rights reserved.

Hanford Environmental Dose Reconstruction Project monthly report

International Nuclear Information System (INIS)

Finch, S.M.

1991-10-01

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doeses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): Source terms; environmental transport; environmental monitoring data; demographics, agriculture, food habits; environmental pathways and dose estimates

Game theory and the warrior diplomat interagency cooperation in stability and reconstruction operations

OpenAIRE

Irmischer, Drew M.

2010-01-01

Approved for public release; distribution is unlimited The U.S. has become increasingly involved with failed and failing states since the end of the Cold War in the 1990s. Further, failed and failing states are forecast to remain a national security issue well into the future. United States involvement with failed and failing states has primarily focused around reconstruction and stability operations, and crisis management efforts. Previous reconstruction and stability efforts have ...

CMS Partial Releases Model, Tools, and Applications. Online and Framework-Light Releases

CERN Document Server

Jones, Christopher D; Meschi, Emilio; Shahzad Muzaffar; Andreas Pfeiffer; Ratnikova, Natalia; Sexton-Kennedy, Elizabeth

2009-01-01

The CMS Software project CMSSW embraces more than a thousand packages organized in subsystems for analysis, event display, reconstruction, simulation, detector description, data formats, framework, utilities and tools. The release integration process is highly automated by using tools developed or adopted by CMS. Packaging in rpm format is a built-in step in the software build process. For several well-defined applications it is highly desirable to have only a subset of the CMSSW full package bundle. For example, High Level Trigger algorithms that run on the Online farm, and need to be rebuilt in a special way, require no simulation, event display, or analysis packages. Physics analysis applications in Root environment require only a few core libraries and the description of CMS specific data formats. We present a model of CMS Partial Releases, used for preparation of the customized CMS software builds, including description of the tools used, the implementation, and how we deal with technical challenges, suc...

Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Finch, S.M.; McMakin, A.H.

1991-04-01

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from released to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demographics, agriculture, food habits; and, environmental pathways and dose estimates

Oak Ridge Dose Reconstruction annual report for calendar year 1997

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-09-01

Calendar year 1997 was the third full year of work on the Oak Ridge Dose Reconstruction. Activities are summarized on the following individual project tasks: Task 1 -- Investigation of radioiodine releases from X-10 radioactive lanthanum processing; Task 2 -- Investigation of mercury releases from Y-12 lithium enrichment; Task 3 -- Investigation of PCBs in the environment near Oak Ridge; Task 4 -- Investigation of radionuclides released from White Oak Creek to the Clinch River; Task 5 -- Systematic searching of records repositories; Task 6 -- Evaluation of the quality of uranium monitoring data and a screening evaluation of potential off-site health risks; and Task 7 -- Performance of screening for additional materials not evaluated in the feasibility study.

Oak Ridge Dose Reconstruction annual report for calendar year 1997

International Nuclear Information System (INIS)

1998-01-01

Calendar year 1997 was the third full year of work on the Oak Ridge Dose Reconstruction. Activities are summarized on the following individual project tasks: Task 1 -- Investigation of radioiodine releases from X-10 radioactive lanthanum processing; Task 2 -- Investigation of mercury releases from Y-12 lithium enrichment; Task 3 -- Investigation of PCBs in the environment near Oak Ridge; Task 4 -- Investigation of radionuclides released from White Oak Creek to the Clinch River; Task 5 -- Systematic searching of records repositories; Task 6 -- Evaluation of the quality of uranium monitoring data and a screening evaluation of potential off-site health risks; and Task 7 -- Performance of screening for additional materials not evaluated in the feasibility study

Radionuclide releases to the Columbia River from Hanford Operations, 1944--1971

International Nuclear Information System (INIS)

Heeb, C.M.; Bates, D.J.

1994-05-01

The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that individuals could have received as a result of radionuclide emissions since 1944 from the Hanford Site. One source of radionuclide releases to the Columbia River was from production reactor operations. This report provides a quantitative estimate of the amount of radioactivity released each month (1944--1971) to the Columbia River from eleven radionuclides as well as from gross beta activity

Surface reconstruction: An effective method for the growth of mismatched materials

Energy Technology Data Exchange (ETDEWEB)

Sun, Yu; Zheng, Beining; Wu, Xiaofeng; Yuan, Long; Wu, Jie; Guo, Hongping; Huang, Keke; Feng, Shouhua, E-mail: shfeng@mail.jlu.edu.cn

2016-01-01

Graphical abstract: High quality thin film of GaSb was fabricated with molecular beam epitaxy technique on the reconstructed Si(1 1 1) surface. - Highlights: • Surface reconstruction formed by different surface treatments controls the heteroepitaxial growth. • Mismatched stress can be effectively released when the mismatched material epi-film tilts out of the epitaxial interface plane to create a coincidence-site lattice. • GaSb films grown on Si(1 1 1)-(5√3 × 5√3)-Sb surface show better crystal quality and morphology for its self-assembled 2D fishbone structure. - Abstract: The crystalline quality of epitaxial films depends on the degree of lattice match between substrates and films. Here, we report a growth strategy for large mismatched epi-films to grow GaSb films on Si(1 1 1) substrates. The epitaxial strategy can be influenced by controlling the surface reconstructions of Sb-treated Si(1 1 1). The film with the best quality was grown on Si(1 1 1)-(5√3 × 5√3)-Sb surface due to the stress release and the formation of a self-assembled 2D fishbone structure. Controlled surface engineering provides an effective pathway towards the growth of the large mismatched materials.

What Lies in the Gutter of a Traumatic Past: Infancia clandestina [Clandestine Childhood], Animated Comics, and the Representation of Violence

Directory of Open Access Journals (Sweden)

María Ghiggia

2018-03-01

Full Text Available This essay focuses on the animated comics in the representation of violence in Benjamín Ávila’s Infancia clandestina [Clandestine Childhood] (2011, a cinematic narrative of the seventies in Argentina. Drawing from animation and comic studies and adopting a formalist approach, the following analysis proposes ways in which the remediation of comics in the film underscores traumatic aspects of state terror and revolutionary violence and the problematic intergenerational transmission of memory of the 1970s–1980s militancy. Specifically, I comment on how the switch from photographic film to the animated frames draws attention to the blank space between the frames and thereby hints at the traumatic in what is left out, repressed, or silenced. While the gaps resist the forward motion of closure, paradoxically they allow for the suture of the frames/fragments in a postmemorial narrative, although not without a trace of the traumatic. Finally, extending the concept of the gutter as a liminal space, I analyze the connection between the animated scenes representing violence and the testimonial and documentary elements placed in the closing titles, a connection that asserts the autobiographical component of the film and enacts the conflictive character of intergenerational memory.

Preliminary results of sequential monitoring of simulated clandestine graves in Colombia, South America, using ground penetrating radar and botany.

Science.gov (United States)

Molina, Carlos Martin; Pringle, Jamie K; Saumett, Miguel; Hernández, Orlando

2015-03-01

In most Latin American countries there are significant numbers of missing people and forced disappearances, 68,000 alone currently in Colombia. Successful detection of shallow buried human remains by forensic search teams is difficult in varying terrain and climates. This research has created three simulated clandestine burial styles at two different depths commonly encountered in Latin America to gain knowledge of optimum forensic geophysics detection techniques. Repeated monitoring of the graves post-burial was undertaken by ground penetrating radar. Radar survey 2D profile results show reasonable detection of ½ clothed pig cadavers up to 19 weeks of burial, with decreasing confidence after this time. Simulated burials using skeletonized human remains were not able to be imaged after 19 weeks of burial, with beheaded and burnt human remains not being able to be detected throughout the survey period. Horizontal radar time slices showed good early results up to 19 weeks of burial as more area was covered and bi-directional surveys were collected, but these decreased in amplitude over time. Deeper burials were all harder to image than shallower ones. Analysis of excavated soil found soil moisture content almost double compared to those reported from temperate climate studies. Vegetation variations over the simulated graves were also noted which would provide promising indicators for grave detection. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The Convolutional Visual Network for Identification and Reconstruction of NOvA Events

Energy Technology Data Exchange (ETDEWEB)

Psihas, Fernanda [Indiana U.

2017-11-22

In 2016 the NOvA experiment released results for the observation of oscillations in the vμ and ve channels as well as ve cross section measurements using neutrinos from Fermilab’s NuMI beam. These and other measurements in progress rely on the accurate identification and reconstruction of the neutrino flavor and energy recorded by our detectors. This presentation describes the first application of convolutional neural network technology for event identification and reconstruction in particle detectors like NOvA. The Convolutional Visual Network (CVN) Algorithm was developed for identification, categorization, and reconstruction of NOvA events. It increased the selection efficiency of the ve appearance signal by 40% and studies show potential impact to the vμ disappearance analysis.

Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Finch, S.M.; McMakin, A.H.

1992-06-01

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, and agriculture; environmental pathways and dose estimates

The reconstruction of thyroid dose following Chernobyl

International Nuclear Information System (INIS)

Stepanenko, V.; Kondrashov, A.; Yaskova, E.; Petin, D.; Skvortsov, V.; Parshkov, E.; Gavrilin, Yu.; Khrousch, V.; Shinkarev, S.; Makarenkova, I.; Volkov, V.; Zvonova, I.; Bratilova, A.; Kaidanovsky, J.; Minenko, V.; Drozdovich, V.; Ulanovsky, A.; Korneev, S.; Heinemann, K.; Pomplun, E.; Hille, R.; Bailiff, A.

1996-01-01

The report presents the overview of several approaches in working out the methods of thyroid internal dose reconstruction following Chernobyl. One of these approaches was developed (IBPh, Moscow; MRRC, Obninsk; IRM, Minsk) using the correlations between the mean dose calculation based on I 131 thyroid content measurements and Cs 137 contamination of territories. The available data on I 131 soil contamination were taken into account. The lack of data on I 131 soil contamination was supposed to be compensated by I 129 measurements in soil samples from contaminated territories. The semiempiric model was developed for dose reconstruction. The comparison of the results obtained by semiempiric model and empirical values are presented. The estimated values of average dose according semiempiric model were used for individual dose reconstruction. The IRH (St.-Petersburg) has developed the following method for individual dose reconstruction: correlation between the total I 131 radioiodine incorporation in thyroid and whole body Cs 137 content during first months after accident. The individual dose reconstruction is also mentioned to be performed using the data on individual milk consumption during first weeks after accident. For evaluation of average doses it is suggested to use the linear correlation: thyroid dose values based on radioiodine thyroid measurements vs Cs 137 contamination, air kerma rate, mean I 131 concentration in the milk. The method for retrospective reconstruction of thyroid dose caused by short-living iodine nuclides released after the Chernobyl accident has been developed by Research Centre, Juelich, Germany. It is based on the constant ratio that these nuclides have with the long-living I 129 . The contamination of soil samples by this nuclide can be used to assess thyroid doses. First results of I 129 contamination values and derived thyroid doses are to be presented

Reconstruction of past methane availability in an Arctic Alaska wetland indicates climate influenced methane release during the past ~12,000 years

Science.gov (United States)

Wooller, Matthew J.; Pohlman, John W.; Gaglioti, Benjamin V.; Langdon, Peter; Jones, Miriam; Anthony, Katey M. Walter; Becker, Kevin W.; Hinrichs, Kai-Uwe; Elvert, Marcus

2012-01-01

Atmospheric contributions of methane from Arctic wetlands during the Holocene are dynamic and linked to climate oscillations. However, long-term records linking climate variability to methane availability in Arctic wetlands are lacking. We present a multi-proxy ~12,000 year paleoecological reconstruction of intermittent methane availability from a radiocarbon-dated sediment core (LQ-West) taken from a shallow tundra lake (Qalluuraq Lake) in Arctic Alaska. Specifically, stable carbon isotopic values of photosynthetic biomarkers and methane are utilized to estimate the proportional contribution of methane-derived carbon to lake-sediment-preserved benthic (chironomids) and pelagic (cladocerans) components over the last ~12,000 years. These results were compared to temperature, hydrologic, and habitat reconstructions from the same site using chironomid assemblage data, oxygen isotopes of chironomid head capsules, and radiocarbon ages of plant macrofossils. Cladoceran ephippia from ~4,000 cal year BP sediments have δ13C values that range from ~−39 to −31‰, suggesting peak methane carbon assimilation at that time. These low δ13C values coincide with an apparent decrease in effective moisture and development of a wetland that included Sphagnum subsecundum. Incorporation of methane-derived carbon by chironomids and cladocerans decreased from ~2,500 to 1,500 cal year BP, coinciding with a temperature decrease. Live-collected chironomids with a radiocarbon age of 1,640 cal year BP, and fossil chironomids from 1,500 cal year BP in the core illustrate that ‘old’ carbon has also contributed to the development of the aquatic ecosystem since ~1,500 cal year BP. The relatively low δ13C values of aquatic invertebrates (as low as −40.5‰) provide evidence of methane incorporation by lake invertebrates, and suggest intermittent climate-linked methane release from the lake throughout the Holocene.

Preparation, characterization, and in vitro cytotoxicity evaluation of a novel anti-tuberculosis reconstruction implant.

Directory of Open Access Journals (Sweden)

JunFeng Dong

Full Text Available Reconstruction materials currently used in clinical for osteoarticular tuberculosis (TB are unsatisfactory due to a variety of reasons. Rifampicin (RFP is a well-known and highly effective first-line anti-tuberculosis (anti-TB drug. Poly-DL-lactide (PDLLA and nano-hydroxyapatite (nHA are two promising materials that have been used both for orthopedic reconstruction and as carriers for drug release. In this study we report the development of a novel anti-TB implant for osteoarticular TB reconstruction using a combination of RFP, PDLLA and nHA.RFP, PDLLA and nHA were used as starting materials to produce a novel anti-TB activity implant by the solvent evaporation method. After manufacture, the implant was characterized and its biodegradation and drug release profile were tested. The in vitro cytotoxicity of the implant was also evaluated in pre-osteoblast MC3T3-E1 cells using multiple methodologies.A RFP/PDLLA/nHA composite was successfully synthesized using the solvent evaporation method. The composite has a loose and porous structure with evenly distributed pores. The production process was steady and no chemical reaction occurred as proved by Fourier Transform Infrared Spectroscopy (FTIR and X-Ray Diffraction (XRD. Meanwhile, the composite blocks degraded and released drug for at least 12 weeks. Evaluation of in vitro cytotoxicity in MC3T3-E1 cells verified that the synthesized composite blocks did not affect cell growth and proliferation.It is feasible to manufacture a novel bioactive anti-TB RFP/PDLLA/nHA composite by the solvent evaporation method. The composite blocks showed appropriate properties such as degradation, drug release and biosafety to MC3T3-E1 cells. In conclusion, the novel composite blocks may have great potential for clinical applications in repairing bone defects caused by osteoarticular TB.

A Novel Kernel-Based Regularization Technique for PET Image Reconstruction

Directory of Open Access Journals (Sweden)

Abdelwahhab Boudjelal

2017-06-01

Full Text Available Positron emission tomography (PET is an imaging technique that generates 3D detail of physiological processes at the cellular level. The technique requires a radioactive tracer, which decays and releases a positron that collides with an electron; consequently, annihilation photons are emitted, which can be measured. The purpose of PET is to use the measurement of photons to reconstruct the distribution of radioisotopes in the body. Currently, PET is undergoing a revamp, with advancements in data measurement instruments and the computing methods used to create the images. These computer methods are required to solve the inverse problem of “image reconstruction from projection”. This paper proposes a novel kernel-based regularization technique for maximum-likelihood expectation-maximization ( κ -MLEM to reconstruct the image. Compared to standard MLEM, the proposed algorithm is more robust and is more effective in removing background noise, whilst preserving the edges; this suppresses image artifacts, such as out-of-focus slice blur.

Using Spherical-Harmonics Expansions for Optics Surface Reconstruction from Gradients.

Science.gov (United States)

Solano-Altamirano, Juan Manuel; Vázquez-Otero, Alejandro; Khikhlukha, Danila; Dormido, Raquel; Duro, Natividad

2017-11-30

In this paper, we propose a new algorithm to reconstruct optics surfaces (aka wavefronts) from gradients, defined on a circular domain, by means of the Spherical Harmonics. The experimental results indicate that this algorithm renders the same accuracy, compared to the reconstruction based on classical Zernike polynomials, using a smaller number of polynomial terms, which potentially speeds up the wavefront reconstruction. Additionally, we provide an open-source C++ library, released under the terms of the GNU General Public License version 2 (GPLv2), wherein several polynomial sets are coded. Therefore, this library constitutes a robust software alternative for wavefront reconstruction in a high energy laser field, optical surface reconstruction, and, more generally, in surface reconstruction from gradients. The library is a candidate for being integrated in control systems for optical devices, or similarly to be used in ad hoc simulations. Moreover, it has been developed with flexibility in mind, and, as such, the implementation includes the following features: (i) a mock-up generator of various incident wavefronts, intended to simulate the wavefronts commonly encountered in the field of high-energy lasers production; (ii) runtime selection of the library in charge of performing the algebraic computations; (iii) a profiling mechanism to measure and compare the performance of different steps of the algorithms and/or third-party linear algebra libraries. Finally, the library can be easily extended to include additional dependencies, such as porting the algebraic operations to specific architectures, in order to exploit hardware acceleration features.

Testing of environmental transfer models using data from the atmospheric release of Iodine-131 from the Hanford site, USA, in 1963. Report of the Dose Reconstruction Working Group of the Biosphere Modelling and Assessment (BIOMASS) Programme, Theme 2

International Nuclear Information System (INIS)

2003-03-01

The IAEA Programme on BIOsphere Modelling and ASSessment (BIOMASS) was launched in Vienna in October 1996. The programme was concerned with developing and improving capabilities to predict the transfer of radionuclides in the environment. The programme had three themes: Theme 1: Radioactive Waste Disposal. The objective was to develop the concept of a standard or reference biosphere for application to the assessment of the long term safety of repositories for radioactive waste. Theme 2: Environmental Releases. BIOMASS provided an international forum for activities aimed at increasing the confidence in methods and models for the assessment of radiation exposure related to environmental releases. Two Working Groups addressed issues concerned with the reconstruction of radiation doses received by people from past releases of radionuclides to the environment and the evaluation of the efficacy of remedial measures. Theme 3: Biosphere Processes. The aim of this Theme was to improve capabilities for modelling the transfer of radionuclides in particular parts of the biosphere identified as being of potential radiological significance and where there were gaps in modelling approaches. This topic was explored using a range of methods including reviews of the literature, model inter-comparison exercises and, where possible, model testing against independent sources of data. Three Working Groups were established to examine the modelling of: (1) long term tritium dispersion in the environment; (2) radionuclide uptake by fruits; and (3) radionuclide migration and accumulation in forest ecosystems. This report describes results of the studies undertaken by the Dose Reconstruction Working Group under Theme 2

RAVE-a Detector-independent vertex reconstruction toolkit

Energy Technology Data Exchange (ETDEWEB)

Waltenberger, Wolfgang [Institute of High Energy Physics, Austrian Academy of Sciences A-1050 Vienna (Austria)], E-mail: walten@hephy.oeaw.ac.at; Mitaroff, Winfried; Moser, Fabian [Institute of High Energy Physics, Austrian Academy of Sciences A-1050 Vienna (Austria)

2007-10-21

A detector-independent toolkit for vertex reconstruction (RAVE) is being developed, along with a standalone framework (VERTIGO) for testing, analyzing and debugging. The core algorithms represent state of the art for geometric vertex finding and fitting by both linear (Kalman filter) and robust estimation methods. Main design goals are ease of use, flexibility for embedding into existing software frameworks, extensibility, and openness. The implementation is based on modern object-oriented techniques, is coded in C++ with interfaces for Java and Python, and follows an open-source approach. A beta release is available.

RAVE-a Detector-independent vertex reconstruction toolkit

International Nuclear Information System (INIS)

Waltenberger, Wolfgang; Mitaroff, Winfried; Moser, Fabian

2007-01-01

A detector-independent toolkit for vertex reconstruction (RAVE) is being developed, along with a standalone framework (VERTIGO) for testing, analyzing and debugging. The core algorithms represent state of the art for geometric vertex finding and fitting by both linear (Kalman filter) and robust estimation methods. Main design goals are ease of use, flexibility for embedding into existing software frameworks, extensibility, and openness. The implementation is based on modern object-oriented techniques, is coded in C++ with interfaces for Java and Python, and follows an open-source approach. A beta release is available

Hanford Environmental Dose Reconstruction Project monthly report, August 1992

International Nuclear Information System (INIS)

McMakin, A.H.; Cannon, S.D.; Finch, S.M.

1992-01-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography; food consumption; and agriculture; and environmental pathway and dose estimates

Mastectomy Skin Necrosis After Breast Reconstruction: A Comparative Analysis Between Autologous Reconstruction and Implant-Based Reconstruction.

Science.gov (United States)

Sue, Gloria R; Lee, Gordon K

2018-05-01

Mastectomy skin necrosis is a significant problem after breast reconstruction. We sought to perform a comparative analysis on this complication between patients undergoing autologous breast reconstruction and patients undergoing 2-stage expander implant breast reconstruction. A retrospective review was performed on consecutive patients undergoing autologous breast reconstruction or 2-stage expander implant breast reconstruction by the senior author from 2006 through 2015. Patient demographic factors including age, body mass index, history of diabetes, history of smoking, and history of radiation to the breast were collected. Our primary outcome measure was mastectomy skin necrosis. Fisher exact test was used for statistical analysis between the 2 patient cohorts. The treatment patterns of mastectomy skin necrosis were then analyzed. We identified 204 patients who underwent autologous breast reconstruction and 293 patients who underwent 2-stage expander implant breast reconstruction. Patients undergoing autologous breast reconstruction were older, heavier, more likely to have diabetes, and more likely to have had prior radiation to the breast compared with patients undergoing implant-based reconstruction. The incidence of mastectomy skin necrosis was 30.4% of patients in the autologous group compared with only 10.6% of patients in the tissue expander group (P care in the autologous group, only 3.2% were treated with local wound care in the tissue expander group (P skin necrosis is significantly more likely to occur after autologous breast reconstruction compared with 2-stage expander implant-based breast reconstruction. Patients with autologous reconstructions are more readily treated with local wound care compared with patients with tissue expanders, who tended to require operative treatment of this complication. Patients considering breast reconstruction should be counseled appropriately regarding the differences in incidence and management of mastectomy skin

Using Spherical-Harmonics Expansions for Optics Surface Reconstruction from Gradients

Directory of Open Access Journals (Sweden)

Juan Manuel Solano-Altamirano

2017-11-01

Full Text Available In this paper, we propose a new algorithm to reconstruct optics surfaces (aka wavefronts from gradients, defined on a circular domain, by means of the Spherical Harmonics. The experimental results indicate that this algorithm renders the same accuracy, compared to the reconstruction based on classical Zernike polynomials, using a smaller number of polynomial terms, which potentially speeds up the wavefront reconstruction. Additionally, we provide an open-source C++ library, released under the terms of the GNU General Public License version 2 (GPLv2, wherein several polynomial sets are coded. Therefore, this library constitutes a robust software alternative for wavefront reconstruction in a high energy laser field, optical surface reconstruction, and, more generally, in surface reconstruction from gradients. The library is a candidate for being integrated in control systems for optical devices, or similarly to be used in ad hoc simulations. Moreover, it has been developed with flexibility in mind, and, as such, the implementation includes the following features: (i a mock-up generator of various incident wavefronts, intended to simulate the wavefronts commonly encountered in the field of high-energy lasers production; (ii runtime selection of the library in charge of performing the algebraic computations; (iii a profiling mechanism to measure and compare the performance of different steps of the algorithms and/or third-party linear algebra libraries. Finally, the library can be easily extended to include additional dependencies, such as porting the algebraic operations to specific architectures, in order to exploit hardware acceleration features.

Ensemble Kalman filter for the reconstruction of the Earth's mantle circulation

Science.gov (United States)

Bocher, Marie; Fournier, Alexandre; Coltice, Nicolas

2018-02-01

Recent advances in mantle convection modeling led to the release of a new generation of convection codes, able to self-consistently generate plate-like tectonics at their surface. Those models physically link mantle dynamics to surface tectonics. Combined with plate tectonic reconstructions, they have the potential to produce a new generation of mantle circulation models that use data assimilation methods and where uncertainties in plate tectonic reconstructions are taken into account. We provided a proof of this concept by applying a suboptimal Kalman filter to the reconstruction of mantle circulation (Bocher et al., 2016). Here, we propose to go one step further and apply the ensemble Kalman filter (EnKF) to this problem. The EnKF is a sequential Monte Carlo method particularly adapted to solve high-dimensional data assimilation problems with nonlinear dynamics. We tested the EnKF using synthetic observations consisting of surface velocity and heat flow measurements on a 2-D-spherical annulus model and compared it with the method developed previously. The EnKF performs on average better and is more stable than the former method. Less than 300 ensemble members are sufficient to reconstruct an evolution. We use covariance adaptive inflation and localization to correct for sampling errors. We show that the EnKF results are robust over a wide range of covariance localization parameters. The reconstruction is associated with an estimation of the error, and provides valuable information on where the reconstruction is to be trusted or not.

Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 5. Accidental Releases

Energy Technology Data Exchange (ETDEWEB)

Peterson, S

2007-08-15

Over the course of fifty-three years, LLNL had six acute releases of tritiated hydrogen gas (HT) and one acute release of tritiated water vapor (HTO) that were too large relative to the annual releases to be included as part of the annual releases from normal operations detailed in Parts 3 and 4 of the Tritium Dose Reconstruction (TDR). Sandia National Laboratories/California (SNL/CA) had one such release of HT and one of HTO. Doses to the maximally exposed individual (MEI) for these accidents have been modeled using an equation derived from the time-dependent tritium model, UFOTRI, and parameter values based on expert judgment. All of these acute releases are described in this report. Doses that could not have been exceeded from the large HT releases of 1965 and 1970 were calculated to be 43 {micro}Sv (4.3 mrem) and 120 {micro}Sv (12 mrem) to an adult, respectively. Two published sets of dose predictions for the accidental HT release in 1970 are compared with the dose predictions of this TDR. The highest predicted dose was for an acute release of HTO in 1954. For this release, the dose that could not have been exceeded was estimated to have been 2 mSv (200 mrem), although, because of the high uncertainty about the predictions, the likely dose may have been as low as 360 {micro}Sv (36 mrem) or less. The estimated maximum exposures from the accidental releases were such that no adverse health effects would be expected. Appendix A lists all accidents and large routine puff releases that have occurred at LLNL and SNL/CA between 1953 and 2005. Appendix B describes the processes unique to tritium that must be modeled after an acute release, some of the time-dependent tritium models being used today, and the results of tests of these models.

Effect of crack-microcracks interaction on energy release rates

Science.gov (United States)

Chudnovsky, A.; Wu, Shaofu

1990-01-01

The energy release rates associated with the main crack advancing into its surrounding damage zone, and the damage zone translation relative to the main crack, as well as the energy of interaction between the crack and the damage zone are analyzed. The displacement and stress fields for this crack-damage interaction problem are reconstructed by employing a semi-empirical stress analysis which involves experimental evaluation of the average microcrack density in the damage zone.

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer, Volume 1

International Nuclear Information System (INIS)

Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K.; Widner, T.E.

1999-01-01

In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the highest doses from I-131 and would have had the highest risks of contracting thyroid cancer. Doses from cow's milk are considerably less . Detailed

Hanford Environmental Dose Reconstruction Project, Quarterly report, September--November 1993

International Nuclear Information System (INIS)

Cannon, S.D.; Finch, S.M.

1993-01-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates); Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates

Hanford Environmental Dose Reconstruction Project monthly report

International Nuclear Information System (INIS)

Finch, S.M.

1990-12-01

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have been have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demographics, agriculture, food habits; and environmental pathways and dose estimates. 3 figs., 3 tabs

An artificial neural network approach to reconstruct the source term of a nuclear accident

International Nuclear Information System (INIS)

Giles, J.; Palma, C. R.; Weller, P.

1997-01-01

This work makes use of one of the main features of artificial neural networks, which is their ability to 'learn' from sets of known input and output data. Indeed, a trained artificial neural network can be used to make predictions on the input data when the output is known, and this feedback process enables one to reconstruct the source term from field observations. With this aim, an artificial neural networks has been trained, using the projections of a segmented plume atmospheric dispersion model at fixed points, simulating a set of gamma detectors located outside the perimeter of a nuclear facility. The resulting set of artificial neural networks was used to determine the release fraction and rate for each of the noble gases, iodines and particulate fission products that could originate from a nuclear accident. Model projections were made using a large data set consisting of effective release height, release fraction of noble gases, iodines and particulate fission products, atmospheric stability, wind speed and wind direction. The model computed nuclide-specific gamma dose rates. The locations of the detectors were chosen taking into account both building shine and wake effects, and varied in distance between 800 and 1200 m from the reactor.The inputs to the artificial neural networks consisted of the measurements from the detector array, atmospheric stability, wind speed and wind direction; the outputs comprised a set of release fractions and heights. Once trained, the artificial neural networks was used to reconstruct the source term from the detector responses for data sets not used in training. The preliminary results are encouraging and show that the noble gases and particulate fission product release fractions are well determined

The RAVE/VERTIGO vertex reconstruction toolkit and framework

Science.gov (United States)

Waltenberger, W.; Mitaroff, W.; Moser, F.; Pflugfelder, B.; Riedel, H. V.

2008-07-01

A detector-independent toolkit for vertex reconstruction (RAVE1) is being developed, along with a standalone framework (VERTIGO2) for testing, analyzing and debugging. The core algorithms represent state-of-the-art for geometric vertex finding and fitting by both linear (Kalman filter) and robust estimation methods. Main design goals are ease of use, flexibility for embedding into existing software frameworks, extensibility, and openness. The implementation is based on modern object-oriented techniques, is coded in C++ with interfaces for Java and Python, and follows an open-source approach. A beta release is available.

Superficial temporal artery flap for reconstruction of complex facial defects: A new algorithm

Directory of Open Access Journals (Sweden)

Tarek M. Elbanoby

2018-03-01

Full Text Available Background A variety of island flaps can be based on the superficial temporal artery with variable tissue composition. They can be used for defect reconstruction, cavity resurfacing, facial hair restoration, or contracture release. Methods Seventy-two patients underwent facial reconstruction using a superficial temporal artery island flap from October 2010 to October 2014. The defects had various etiologies, including trauma, burns, tumors, exposed hardware, and congenital causes. We classified the patients by indication into 5 groups: cavity resurfacing, contracture release, facial hair restoration, skin coverage, and combined. The demographic data of the patients, defect characteristics, operative procedures, postoperative results, and complications were retrospectively documented. The follow-up period ranged from 24 to 54 months. Results A total of 24 females and 48 males were included in this study. The mean age of the patients was 33.7±15.6 years. The flaps were used for contracture release in 13 cases, cavity resurfacing in 10 cases, skin coverage in 17 cases, facial hair restoration in 19 cases, and combined defects in 13 cases. No major complications were reported. Conclusion: Based on our experiences with the use of superficial temporal artery island flaps, we have developed a detailed approach for the optimal management of patients with composite facial defects. The aim of this article is to provide the reader with a systematic algorithm to use for such patients.

Ensemble Kalman filter for the reconstruction of the Earth's mantle circulation

Directory of Open Access Journals (Sweden)

M. Bocher

2018-02-01

Full Text Available Recent advances in mantle convection modeling led to the release of a new generation of convection codes, able to self-consistently generate plate-like tectonics at their surface. Those models physically link mantle dynamics to surface tectonics. Combined with plate tectonic reconstructions, they have the potential to produce a new generation of mantle circulation models that use data assimilation methods and where uncertainties in plate tectonic reconstructions are taken into account. We provided a proof of this concept by applying a suboptimal Kalman filter to the reconstruction of mantle circulation (Bocher et al., 2016. Here, we propose to go one step further and apply the ensemble Kalman filter (EnKF to this problem. The EnKF is a sequential Monte Carlo method particularly adapted to solve high-dimensional data assimilation problems with nonlinear dynamics. We tested the EnKF using synthetic observations consisting of surface velocity and heat flow measurements on a 2-D-spherical annulus model and compared it with the method developed previously. The EnKF performs on average better and is more stable than the former method. Less than 300 ensemble members are sufficient to reconstruct an evolution. We use covariance adaptive inflation and localization to correct for sampling errors. We show that the EnKF results are robust over a wide range of covariance localization parameters. The reconstruction is associated with an estimation of the error, and provides valuable information on where the reconstruction is to be trusted or not.

Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

McMakin, A.H.; Cannon, S.D.; Finch, S.M.

1992-07-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed

Petroleum and hazardous material releases from industrial facilities associated with Hurricane Katrina.

Science.gov (United States)

Santella, Nicholas; Steinberg, Laura J; Sengul, Hatice

2010-04-01

Hurricane Katrina struck an area dense with industry, causing numerous releases of petroleum and hazardous materials. This study integrates information from a number of sources to describe the frequency, causes, and effects of these releases in order to inform analysis of risk from future hurricanes. Over 200 onshore releases of hazardous chemicals, petroleum, or natural gas were reported. Storm surge was responsible for the majority of petroleum releases and failure of storage tanks was the most common mechanism of release. Of the smaller number of hazardous chemical releases reported, many were associated with flaring from plant startup, shutdown, or process upset. In areas impacted by storm surge, 10% of the facilities within the Risk Management Plan (RMP) and Toxic Release Inventory (TRI) databases and 28% of SIC 1311 facilities experienced accidental releases. In areas subject only to hurricane strength winds, a lower fraction (1% of RMP and TRI and 10% of SIC 1311 facilities) experienced a release while 1% of all facility types reported a release in areas that experienced tropical storm strength winds. Of industrial facilities surveyed, more experienced indirect disruptions such as displacement of workers, loss of electricity and communication systems, and difficulty acquiring supplies and contractors for operations or reconstruction (55%), than experienced releases. To reduce the risk of hazardous material releases and speed the return to normal operations under these difficult conditions, greater attention should be devoted to risk-based facility design and improved prevention and response planning.

Results of large scale thyroid dose reconstruction in Ukraine

International Nuclear Information System (INIS)

Likhtarev, I.; Sobolev, B.; Kairo, I.; Tabachny, L.; Jacob, P.; Proehl, G.; Goulko, G.

1996-01-01

In 1993, the Ukrainian Ministry on Chernobyl Affairs initiated a large scale reconstruction of thyroid exposures to radioiodine after the Chernobyl accident. The objective was to provide the state policy on social compensations with a scientific background. About 7000 settlements from five contaminated regions have gotten certificates of thyroid exposure since then. Certificates contain estimates of the average thyroid dose from 131 I for seven age groups. The primary dose estimates used about 150000 direct measurements of the 131 I activity in the thyroid glands of inhabitants from Chernigiv, Kiev, Zhytomyr, and also Vinnytsa regions. Parameters of the assumed intake function were related to environmental and questionnaire data. The dose reconstruction for the remaining territory was based on empirical relations between intake function parameters and the 137 Cs deposition. The relationship was specified by the distance and the direction to the Chernobyl Nuclear Power Plant. The relations were first derived for territories with direct measurements and then they were spread on other areas using daily iodine releases and atmospheric transportation routes. The results of the dose reconstruction allowed to mark zones on the territory of Ukraine according to the average levels of thyroid exposures. These zones underlay a policy of post-accidental health care and social compensations. Another important application of the thyroid dose reconstruction is the radiation risk assessment of thyroid cancer among people exposed during childhood due to the Chernobyl accident

The Hanford Environmental Dose Reconstruction (HEDR) Project: Technical approach

International Nuclear Information System (INIS)

Napier, B.A.; Freshley, M.D.; Gilbert, R.O.; Haerer, H.A.; Morgan, L.G.; Rhoads, R.E.; Woodruff, R.K.

1990-01-01

Historical measurements and current assessment techniques are being combined to estimate potential radiation doses to people from radioactive releases to the air, the Columbia River, soils, and ground water at the Hanford Site since 1944. Environmental contamination from these releases has been monitored, at varying levels of detail, for 45 yr. Phase I of the Hanford Environmental Reconstruction Project will estimate the magnitude of potential doses, their areal extends, and their associated uncertainties. The Phase I study area comprises 10 counties in eastern Washington and northern Oregon, within a 100-mi radius of the site, including a stretch of the Columbia River that was most significantly affected. These counties contain a range of projected and measured contaminant levels, environmental exposure pathways, and population groups. Phase I dose estimates are being developed for the periods 1944 through 1947 for air pathways and 1964 through 1966 for river pathways. Important radionuclide/pathway combinations include fission products, such as 131 I, in milk for early atmospheric releases and activation products, such as 32 P and 65 Zn, in fish for releases to the river. Potential doses range over several orders of magnitude within the study area. We will expand the time periods and study are in three successive phases, as warranted by results of Phase I

Amphiphilic polymer based on fluoroalkyl and PEG side chains for fouling release coating

Science.gov (United States)

Cong, W. W.; Wang, K.; Yu, X. Y.; Zhang, H. Q.; Lv, Z.; Gui, T. J.

2017-12-01

Under static conditions, fouling release coating could not express good release property to marine organisms. Amphiphilic polymer with mixture of fluorinated monomer and short side group of polyethylene glycol (PEG) was synthesized. And also we studied the ability of amphiphilic polymer to influence the surface properties and how it controlled the adhesion of marine organisms to coated surfaces. By incorporating fluorinated monomer and PEG side chain into the polymer, the effect of incorporating both polar and non-polar groups on fouling-release coating could be studied. The dry surface was characterized by three-dimensional digital microscopy and scanning electron microscopy (SEM), and the morphology of the amphiphilic fouling release coating showed just like flaky petal. The amphiphilic polymer in fouling release coating tended to reconstruct in water, and the ability was examined by static contact angle, which was smaller than the PDMS (polydimethylsiloxane) fouling release coating. Also surface energy was calculated by three solvents, and surface energy of amphiphilic fouling release coating was higher than that of the PDMS fouling release coating. To understand more about its fouling release property, seawater exposure method was adopted in gulf of Qingdao port. Fewer diatoms Navicula were found in biofilm after using amphiphilic fouling release coating. In general, coating containing both PEG and fluorinated side chain possessed certain fouling release property.

Reconstruction of hand contracture by reverse ulnar perforator flap

Directory of Open Access Journals (Sweden)

Cengiz Eser

2016-04-01

Full Text Available Hand burn scar contractures affect patients in aesthetic and functional aspects. After releasing these scars, the defects should be repaired. The reconstruction methods include primary suturation, Z plasty, skin grafting, local or free flaps, etc. All methods have their own advantages and disadvantages. One of the most useful flaps is the reverse ulnar perforator flap. We performed a two-staged procedure for repairing a post-burn contracture release defect in a 40-year-old male. In the first stage we applied reverse ulnar perforator flap for the hand defect, and ulnar artery and vein repair in the second stage. In conclusion, this two-staged procedure is a non-primary but useful option for hand and finger defects and prevents major vascular structure damage of the forearm. [Hand Microsurg 2016; 5(1.000: 40-43

Algebraic reconstruction techniques for spectral reconstruction in diffuse optical tomography

International Nuclear Information System (INIS)

Brendel, Bernhard; Ziegler, Ronny; Nielsen, Tim

2008-01-01

Reconstruction in diffuse optical tomography (DOT) necessitates solving the diffusion equation, which is nonlinear with respect to the parameters that have to be reconstructed. Currently applied solving methods are based on the linearization of the equation. For spectral three-dimensional reconstruction, the emerging equation system is too large for direct inversion, but the application of iterative methods is feasible. Computational effort and speed of convergence of these iterative methods are crucial since they determine the computation time of the reconstruction. In this paper, the iterative methods algebraic reconstruction technique (ART) and conjugated gradients (CGs) as well as a new modified ART method are investigated for spectral DOT reconstruction. The aim of the modified ART scheme is to speed up the convergence by considering the specific conditions of spectral reconstruction. As a result, it converges much faster to favorable results than conventional ART and CG methods

Functional reconstruction of ischemic contracture in the

Directory of Open Access Journals (Sweden)

TANG Hao

2011-04-01

Full Text Available 【Abstract】Objective: To discuss the method of functional reconstruction of ischemic contracture in the lower limb and propose a classification protocol for ischemic contracture in the lower limb based on its severity and prognosis. Methods: A total of 42 patients with ischemic contracture in the lower limb were included in this study. According to different types of disturbance and degrees of severity, surgical reconstructions consisting of nerve decompression, tendon lengthening or transfer, intrinsic foot muscle release and sural-tibial nerve anastomosis were performed in every patient. Results: Postoperatively, all patients were able to walk on flat ground. Drop foot was corrected in 10 patients, and 5 patients still felt some difficulty during stair activity. Split Achilles tendon transfer to flexor hallucis longus tendon was performed in 12 patients, and their walking stability was improved. Seven patients accepted ipsilateral suraltibial nerve anastomosis, and sensitivity recovery reached to S2 in 2 patients and S3 in 5 patients. Conclusions: Ischemic contracture in the lower limb is a devastating complication after lower limb trauma. The prevention of contracture is much more important than the treatment of an established contracture. Split Achilles tendon transfer to flexor hallucis longus tendon and sural-tibial nerve anastomosis, which was initially implemented by us, could improve the functional recovery of ischemic contracture in lower limbs, and thus provides a new alternative for functional reconstruction of ischemic contracture in the lower limb. Key words: Ischemic contracture; Classification; Recovery of function

Alcaldes mayores y subdelegados frente a la siembra clandestina de tabaco: Papantla, 1765-1806 Alcaldes Mayores and Subdelegados coping with Tobacco Clandestine Sowing: Papantla, 1765-1806

Directory of Open Access Journals (Sweden)

Georgina Moreno Coello

2012-12-01

Full Text Available Este trabajo tiene como objeto explorar las estrategias que permitieron la persistencia de la siembra clandestina de tabaco en Nueva España, en particular en la región de Papantla. Analizar las relaciones entre los alcaldes mayores, subdelegados y empleados del monopolio del tabaco, enfatizando la protección informal de la que gozó el cultivo ilegal de parte de las autoridades provinciales y examinar cuál pudo ser el destino del ahorro, así como de las ganancias obtenidas del tabaco ilegal, particularmente en el financiamiento de actividades comerciales y crediticias que llevaban a cabo alcaldes mayores y subdelegados, especialmente en el repartimiento de mercancías.This paper explores the strategies that allowed for a persistent clandestine tobacco sowing in New Spain, mainly in the region of Papantla. It analyzes the relationship between alcaldes mayores, subdelegados and employees of the tobacco monopoly, emphasizing the informal protection given to illegal sowings by provincial authorities. It also examines the potential allocation of savings and profits from illegal tobacco, mainly in the financing of commercial activities undertaken by alcaldes mayores and subdelegados, particularly for the repartimiento.

Evaluating the robustness of three ring-width measurement methods for growth release reconstruction

Czech Academy of Sciences Publication Activity Database

Maes, S. L.; Vannoppen, A.; Altman, Jan; Van den Bulcke, J.; Decocq, G.; De Mil, T.; Depauw, L.; Landuyt, D.; Perring, M. P.; Van Acker, J.; Vanhellemont, M.; Verheyen, K.

2017-01-01

Roč. 46, DEC 2017 (2017), s. 67-76 ISSN 1125-7865 R&D Projects: GA ČR(CZ) GA17-07378S; GA ČR(CZ) GA14-12262S Institutional support: RVO:67985939 Keywords : Dendrochronology * Growth release * Ring-width measurement Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 2.259, year: 2016

The ALICE Software Release Validation cluster

International Nuclear Information System (INIS)

Berzano, D; Krzewicki, M

2015-01-01

One of the most important steps of software lifecycle is Quality Assurance: this process comprehends both automatic tests and manual reviews, and all of them must pass successfully before the software is approved for production. Some tests, such as source code static analysis, are executed on a single dedicated service: in High Energy Physics, a full simulation and reconstruction chain on a distributed computing environment, backed with a sample “golden” dataset, is also necessary for the quality sign off. The ALICE experiment uses dedicated and virtualized computing infrastructures for the Release Validation in order not to taint the production environment (i.e. CVMFS and the Grid) with non-validated software and validation jobs: the ALICE Release Validation cluster is a disposable virtual cluster appliance based on CernVM and the Virtual Analysis Facility, capable of deploying on demand, and with a single command, a dedicated virtual HTCondor cluster with an automatically scalable number of virtual workers on any cloud supporting the standard EC2 interface. Input and output data are externally stored on EOS, and a dedicated CVMFS service is used to provide the software to be validated. We will show how the Release Validation Cluster deployment and disposal are completely transparent for the Release Manager, who simply triggers the validation from the ALICE build system's web interface. CernVM 3, based entirely on CVMFS, permits to boot any snapshot of the operating system in time: we will show how this allows us to certify each ALICE software release for an exact CernVM snapshot, addressing the problem of Long Term Data Preservation by ensuring a consistent environment for software execution and data reprocessing in the future. (paper)

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer, Volume 1

Energy Technology Data Exchange (ETDEWEB)

Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K.; Widner, T.E.

1999-07-01

In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the highest doses from I-131 and would have had the highest risks of contracting thyroid cancer. Doses from cow

The RAVE/VERTIGO vertex reconstruction toolkit and framework

Energy Technology Data Exchange (ETDEWEB)

Waltenberger, W; Mitaroff, W; Moser, F; Pflugfelder, B; Riedel, H V [Austrian Academy of Sciences, Institute of High Energy Physics, A-1050 Vienna (Austria)], E-mail: walten@hephy.oeaw.ac.at

2008-07-15

A detector-independent toolkit for vertex reconstruction (RAVE{sup 1}) is being developed, along with a standalone framework (VERTIGO{sup 2}) for testing, analyzing and debugging. The core algorithms represent state-of-the-art for geometric vertex finding and fitting by both linear (Kalman filter) and robust estimation methods. Main design goals are ease of use, flexibility for embedding into existing software frameworks, extensibility, and openness. The implementation is based on modern object-oriented techniques, is coded in C++ with interfaces for Java and Python, and follows an open-source approach. A beta release is available.

Evaluation of the spline reconstruction technique for PET

Energy Technology Data Exchange (ETDEWEB)

Kastis, George A., E-mail: gkastis@academyofathens.gr; Kyriakopoulou, Dimitra [Research Center of Mathematics, Academy of Athens, Athens 11527 (Greece); Gaitanis, Anastasios [Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens 11527 (Greece); Fernández, Yolanda [Centre d’Imatge Molecular Experimental (CIME), CETIR-ERESA, Barcelona 08950 (Spain); Hutton, Brian F. [Institute of Nuclear Medicine, University College London, London NW1 2BU (United Kingdom); Fokas, Athanasios S. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB30WA (United Kingdom)

2014-04-15

point-source studies. In all simulated phantoms, the SRT exhibits higher contrast and lower bias than FBP at all noise levels, by increasing the COV in the reconstructed images. Finally, in real studies, whereas the contrast of the cold chambers are similar for both algorithms, the SRT reconstructed images of the NEMA phantom exhibit slightly higher COV values than those of FBP. In the Derenzo phantom, SRT resolves the 2-mm separated holes slightly better than FBP. The small-animal and human reconstructions via SRT exhibit slightly higher resolution and contrast than the FBP reconstructions. Conclusions: The SRT provides images of higher resolution, higher contrast, and lower bias than FBP, by increasing slightly the noise in the reconstructed images. Furthermore, it eliminates streak artifacts outside the object boundary. Unlike other analytic algorithms, the reconstruction time of SRT is comparable with that of FBP. The source code for SRT will become available in a future release of STIR.

Improved protein structure reconstruction using secondary structures, contacts at higher distance thresholds, and non-contacts.

Science.gov (United States)

Adhikari, Badri; Cheng, Jianlin

2017-08-29

Residue-residue contacts are key features for accurate de novo protein structure prediction. For the optimal utilization of these predicted contacts in folding proteins accurately, it is important to study the challenges of reconstructing protein structures using true contacts. Because contact-guided protein modeling approach is valuable for predicting the folds of proteins that do not have structural templates, it is necessary for reconstruction studies to focus on hard-to-predict protein structures. Using a data set consisting of 496 structural domains released in recent CASP experiments and a dataset of 150 representative protein structures, in this work, we discuss three techniques to improve the reconstruction accuracy using true contacts - adding secondary structures, increasing contact distance thresholds, and adding non-contacts. We find that reconstruction using secondary structures and contacts can deliver accuracy higher than using full contact maps. Similarly, we demonstrate that non-contacts can improve reconstruction accuracy not only when the used non-contacts are true but also when they are predicted. On the dataset consisting of 150 proteins, we find that by simply using low ranked predicted contacts as non-contacts and adding them as additional restraints, can increase the reconstruction accuracy by 5% when the reconstructed models are evaluated using TM-score. Our findings suggest that secondary structures are invaluable companions of contacts for accurate reconstruction. Confirming some earlier findings, we also find that larger distance thresholds are useful for folding many protein structures which cannot be folded using the standard definition of contacts. Our findings also suggest that for more accurate reconstruction using predicted contacts it is useful to predict contacts at higher distance thresholds (beyond 8 Å) and predict non-contacts.

Integration of models for the Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Napier, B.A.

1991-01-01

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation dose that individuals could have received as a result of emissions from nuclear operations at Hanford since 1944. The objective of phase 1 of the project was to demonstrate through calculations that adequate models and support data exist or could be developed to allow realistic estimations of doses to individuals from releases of radionuclides to the environment that occurred as long as 45 years ago. Much of the data used in phase 1 was preliminary; therefore, the doses calculated must be considered preliminary approximations. This paper describes the integration of various models that was implemented for initial computer calculations. Models were required for estimating the quantity of radioactive material released, for evaluating its transport through the environment, for estimating human exposure, and for evaluating resultant doses

A New Method for Coronal Magnetic Field Reconstruction

Science.gov (United States)

Yi, Sibaek; Choe, Gwang-Son; Cho, Kyung-Suk; Kim, Kap-Sung

2017-08-01

A precise way of coronal magnetic field reconstruction (extrapolation) is an indispensable tool for understanding of various solar activities. A variety of reconstruction codes have been developed so far and are available to researchers nowadays, but they more or less bear this and that shortcoming. In this paper, a new efficient method for coronal magnetic field reconstruction is presented. The method imposes only the normal components of magnetic field and current density at the bottom boundary to avoid the overspecification of the reconstruction problem, and employs vector potentials to guarantee the divergence-freeness. In our method, the normal component of current density is imposed, not by adjusting the tangential components of A, but by adjusting its normal component. This allows us to avoid a possible numerical instability that on and off arises in codes using A. In real reconstruction problems, the information for the lateral and top boundaries is absent. The arbitrariness of the boundary conditions imposed there as well as various preprocessing brings about the diversity of resulting solutions. We impose the source surface condition at the top boundary to accommodate flux imbalance, which always shows up in magnetograms. To enhance the convergence rate, we equip our code with a gradient-method type accelerator. Our code is tested on two analytical force-free solutions. When the solution is given only at the bottom boundary, our result surpasses competitors in most figures of merits devised by Schrijver et al. (2006). We have also applied our code to a real active region NOAA 11974, in which two M-class flares and a halo CME took place. The EUV observation shows a sudden appearance of an erupting loop before the first flare. Our numerical solutions show that two entwining flux tubes exist before the flare and their shackling is released after the CME with one of them opened up. We suggest that the erupting loop is created by magnetic reconnection between

Breast reconstruction after mastectomy

Directory of Open Access Journals (Sweden)

Daniel eSchmauss

2016-01-01

Full Text Available Breast cancer is the leading cause of cancer death in women worldwide. Its surgical approach has become less and less mutilating in the last decades. However, the overall number of breast reconstructions has significantly increased lately. Nowadays breast reconstruction should be individualized at its best, first of all taking into consideration oncological aspects of the tumor, neo-/adjuvant treatment and genetic predisposition, but also its timing (immediate versus delayed breast reconstruction, as well as the patient’s condition and wish. This article gives an overview over the various possibilities of breast reconstruction, including implant- and expander-based reconstruction, flap-based reconstruction (vascularized autologous tissue, the combination of implant and flap, reconstruction using non-vascularized autologous fat, as well as refinement surgery after breast reconstruction.

The clandestine multiple graves in Malaysia: The first mass identification operation of human skeletal remains.

Science.gov (United States)

Mohd Noor, Mohd Suhani; Khoo, Lay See; Zamaliana Alias, Wan Zafirah; Hasmi, Ahmad Hafizam; Ibrahim, Mohamad Azaini; Mahmood, Mohd Shah

2017-09-01

The first ever mass identification operation of skeletal remains conducted for the clandestine graves in Malaysia consisted of 165 individuals unearthed from 28 human trafficking transit camps located in Wang Kelian, along the Thai-Malaysia border. A DVI response was triggered in which expert teams comprising of pathologists, anthropologists, odontologists, radiologists and DNA experts were gathered at the identified operation centre. The Department of Forensic Medicine, Hospital Sultanah Bahiyah, Alor Star, Kedah, located approximately 75km away from Wang Kelian, was temporarily converted into a victim identification centre (VIC) as it is the nearest available forensic facility to the mass grave site. The mortuary operation was conducted over a period of 3 months from June to September 2015, and was divided into two phases; phase 1 involving the postmortem examination of the remains of 116 suspected individuals and for phase 2 the remains of 49 suspected individuals. The fact that the graves were of unknown individuals afforded the mass identification operation a sufficient duration of 2 weeks as preparatory phase enabling procedurals and daily victim identification workflow to be established, and the setting up of a temporary body storage for the designated mortuary. The temporary body storage has proven to be a significant factor in enabling the successful conclusion of the VIC operation to the final phase of temporary controlled burials. Recognition from two international observers, Mr. Andréas Patiño Umaña, from the International Committee of Red Cross (ICRC) and Prof. Noel Woodford from Victoria Institute of Forensic Medicine (VIFM) had proven the mortuary operation was in compliance to the international quality and standards. The overall victim identification and mortuary operation identified a number of significant challenges, in particular the management of commingled human remains as well as the compilation of postmortem data in the absence of

Breast reconstruction - implants

Science.gov (United States)

Breast implants surgery; Mastectomy - breast reconstruction with implants; Breast cancer - breast reconstruction with implants ... harder to find a tumor if your breast cancer comes back. Getting breast implants does not take as long as breast reconstruction ...

Hypsometric Amplification of Greenland Ice Sheet Meltwater Release

Science.gov (United States)

van As, D.; Hasholt, B.; Mikkelsen, A. B.; Holtegaard Nielsen, M.; Box, J.; Claesson Liljedahl, L.; Lindback, K.; Pitcher, L. H.

2017-12-01

Proglacial discharge monitoring provides valuable insights in Greenland ice sheet meltwater release. We use a 2006-2016 discharge time series from the Watson River draining 12000 km2 of the ice sheet in southwest Greenland to investigate the large variability in catchment-total meltwater production. An observationally-constrained reconstruction of past discharge shows that meltwater release has on average increased by a factor of 1.5 since 2003 compared to the 1949-2002 period, and that interannual variability has disproportionally increased by a factor of 2.1, suggesting that melt amplifiers are at play. We derive a hypsometric amplification factor of 1.6, which is the result of the exponential melt area increase with rising temperature. Peak meltwater discharge events such as during the July 2012 flooding are due to this and other melt amplifiers, but also require intense melting over a period exceeding the multi-day transit time for high-elevation meltwater to pass through the glacial drainage system.

Herwig++ 2.3 Release Note

CERN Document Server

Bähr, M; Gigg, M; Grellscheid, D; Hamilton, K; Plätzer, S; Richardson, P; Seymour, M H; Tully, J

2008-01-01

A new release of the Monte Carlo program Herwig++ (version 2.3) is now available. This version includes a number of improvements including: the extension of the program to lepton-hadron collisions; the inclusion of several processes accurate at next-to-leading order in the POsitive Weight Hardest Emission Generator (POWHEG) scheme; the inclusion of three-body decays and finite-width effects in Beyond the Standard Model (BSM) physics processes; a new procedure for reconstructing the kinematics of the parton shower based on the colour structure of the hard scattering process; a new model for baryon decays including excited baryon multiplets; the addition of a soft component to the multiple scattering model of the underlying event; new matrix elements for Deep Inelastic Scattering (DIS) and e+e- processes.

Adaptive algebraic reconstruction technique

International Nuclear Information System (INIS)

Lu Wenkai; Yin Fangfang

2004-01-01

Algebraic reconstruction techniques (ART) are iterative procedures for reconstructing objects from their projections. It is proven that ART can be computationally efficient by carefully arranging the order in which the collected data are accessed during the reconstruction procedure and adaptively adjusting the relaxation parameters. In this paper, an adaptive algebraic reconstruction technique (AART), which adopts the same projection access scheme in multilevel scheme algebraic reconstruction technique (MLS-ART), is proposed. By introducing adaptive adjustment of the relaxation parameters during the reconstruction procedure, one-iteration AART can produce reconstructions with better quality, in comparison with one-iteration MLS-ART. Furthermore, AART outperforms MLS-ART with improved computational efficiency

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer- APPENDICES Appendices-Volume 1A

International Nuclear Information System (INIS)

Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K.; Widner, T.E.

1999-01-01

This report consists of all the appendices for the report described below: In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values as appendices. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the highest doses from I-131 and would have had the highest

Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956)- An Assessment of Quantities released, Off-Site Radiation Doses, and Potential Excess Risks of Thyroid Cancer- APPENDICES Appendices-Volume 1A

Energy Technology Data Exchange (ETDEWEB)

Apostoaei, A.I.; Burns, R.E.; Hoffman, F.O.; Ijaz, T.; Lewis, C.J.; Nair, S.K.; Widner, T.E.

1999-07-01

This report consists of all the appendices for the report described below: In the early 1990s, concern about the Oak Ridge Reservation's past releases of contaminants to the environment prompted Tennessee's public health officials to pursue an in-depth study of potential off-site health effects at Oak Ridge. This study, the Oak Ridge dose reconstruction, was supported by an agreement between the U.S. Department of Energy (DOE) and the State of Tennessee, and was overseen by a 12-member panel appointed by Tennessee's Commissioner of Health. One of the major contaminants studied in the dose reconstruction was radioactive iodine, which was released to the air by X-10 (now called Oak Ridge National Laboratory) as it processed spent nuclear reactor fuel from 1944 through 1956. The process recovered radioactive lanthanum for use in weapons development. Iodine concentrates in the thyroid gland so health concerns include various diseases of the thyroid, such as thyroid cancer. The large report, ''Iodine-131 Releases from Radioactive Lanthanum Processing at the X-10 Site in Oak Ridge, Tennessee (1944-1956) - An Assessment of Quantities Released, Off-site Radiation Doses, and Potential Excess Risks of Thyroid Cancer,'' is in two volumes. Volume 1 is the main body of the report, and Volume 1A, which has the same title, consists of 22 supporting appendices. Together, these reports serve the following purposes: (1) describe the methodologies used to estimate the amount of iodine-131 (I-131) released; (2) evaluate I-131's pathway from air to vegetation to food to humans; (3) estimate doses received by human thyroids; (4) estimate excess risk of acquiring a thyroid cancer during ones lifetime; and (5) provide equations, examples of historical documents used, and tables of calculated values as appendices. Results indicate that females born in 1952 who consumed milk from a goat pastured a few miles east of X-10 received the highest doses from

Overview of the Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Shipler, D.B.; Napier, B.A.; Ikenberry, T.A.

1992-04-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that specific and representative individuals and populations may have received as a result of releases of radioactive materials from historical operations at the Hanford Site. These dose estimates would account for the uncertainties of information regarding facilities operations, environmental monitoring, demography, food consumption and lifestyles, and the variability of natural phenomena. Other objectives of the HEDR Project include: supporting the Hanford Thyroid Disease Study (HTDS), declassifying Hanford-generated information and making it available to the public, performing high-quality, credible science, and conducting the project in an open, public forum. The project is briefly described

Fabrication and characterization of a rapid prototyped tissue engineering scaffold with embedded multicomponent matrix for controlled drug release

DEFF Research Database (Denmark)

Chen, Muwan; Le, Dang Q S; Hein, San

2012-01-01

Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone......, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount...... of individual components, the scaffold can find application in other tissue engineering areas that need local sustained release of drug....

Draft Air Pathway Report: Phase 1 of the Hanford Environmental Dose Reconstruction Project

Energy Technology Data Exchange (ETDEWEB)

1990-07-20

This report summarizes the air pathway portion of the first phase of the Hanford Environmental Dose Reconstruction (HEDR) Project, conducted by Battelle staff at the Pacific Northwest Laboratory under the direction of an independent Technical Steering Panel. The HEDR Project is estimating historical radiation doses that could have been received by populations near the Department of Energy's Hanford Site, in southeastern Washington State. Phase 1 of the air-pathway dose reconstruction sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals'' for the period 1944--1947. 4 refs., 10 figs., 9 tabs.

United States-assisted studies on dose reconstruction in the former Soviet Union

International Nuclear Information System (INIS)

Anspaugh, L.R.; Bouville, A.

1995-12-01

Following the Chernobyl accident, the US and the USSR entered into an agreement to work on the safety of civilian nuclear reactors; one aspect of that work was to study the environmental transport and health effects of radionuclides released by the accident. After the break-up of the USSR separate agreements were established between the US and Ukraine, Belarus, and Russia to continue work on dose reconstruction and epidemiologic studies of health effects from exposure to external radiation and the incorporation of radionuclides. Studies in Belarus and Ukraine related to the Chernobyl accident now emphasize epidemiologic: studies of childhood-thyroid cancer and leukemia, and eye-lens-cataract formation in liquidators. Supporting studies on dose reconstruction emphasize a variety of ecological, physical, and biological techniques. Studies being conducted in Russia currently emphasize health effects in the workers and the population around the Mayak Industrial Association. As this production complex is an analogue of the US Hanford Works, advantage is being taken of the US experience in conducting a similar, recently completed dose-reconstruction study. In all cases the primary work on dose reconstruction is being performed by scientists from the former Soviet Union. US assistance is in the form of expert consultation and participation, exchange visits, provision of supplies and equipment, and other forms of local assistance

Estimation of 1945 to 1957 food consumption. Hanford Environmental Dose Reconstruction Project

Energy Technology Data Exchange (ETDEWEB)

Anderson, D.M.; Bates, D.J.; Marsh, T.L.

1993-07-01

This report details the methods used and the results of the study on the estimated historic levels of food consumption by individuals in the Hanford Environmental Dose Reconstruction (HEDR) study area from 1945--1957. This period includes the time of highest releases from Hanford and is the period for which data are being collected in the Hanford Thyroid Disease Study. These estimates provide the food-consumption inputs for the HEDR database of individual diets. This database will be an input file in the Hanford Environmental Dose Reconstruction Integrated Code (HEDRIC) computer model that will be used to calculate the radiation dose. The report focuses on fresh milk, eggs, lettuce, and spinach. These foods were chosen because they have been found to be significant contributors to radiation dose based on the Technical Steering Panel dose decision level.

Parameters used in the environmental pathways (DESCARTES) and radiological dose (CIDER) modules of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC) for the air pathway. Hanford Environmental Dose Reconstruction Project

Energy Technology Data Exchange (ETDEWEB)

Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

1992-09-01

This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site since 1944. This work is being done by staff at Battelle, Pacific Northwest Laboratories (Battelle) under a contract with the Centers for Disease Control (CDC) with technical direction provided by an independent Technical Steering Panel (TSP). The objective of this report is to-document the environmental accumulation and dose-assessment parameters that will be used to estimate the impacts of past Hanford Site airborne releases. During 1993, dose estimates made by staff at Battelle will be used by the Fred Hutchinson Cancer Research Center as part of the Hanford Thyroid Disease Study (HTDS). This document contains information on parameters that are specific to the airborne release of the radionuclide iodine-131. Future versions of this document will include parameter information pertinent to other pathways and radionuclides.

Computed Tomography Image Quality Evaluation of a New Iterative Reconstruction Algorithm in the Abdomen (Adaptive Statistical Iterative Reconstruction-V) a Comparison With Model-Based Iterative Reconstruction, Adaptive Statistical Iterative Reconstruction, and Filtered Back Projection Reconstructions.

Science.gov (United States)

Goodenberger, Martin H; Wagner-Bartak, Nicolaus A; Gupta, Shiva; Liu, Xinming; Yap, Ramon Q; Sun, Jia; Tamm, Eric P; Jensen, Corey T

The purpose of this study was to compare abdominopelvic computed tomography images reconstructed with adaptive statistical iterative reconstruction-V (ASIR-V) with model-based iterative reconstruction (Veo 3.0), ASIR, and filtered back projection (FBP). Abdominopelvic computed tomography scans for 36 patients (26 males and 10 females) were reconstructed using FBP, ASIR (80%), Veo 3.0, and ASIR-V (30%, 60%, 90%). Mean ± SD patient age was 32 ± 10 years with mean ± SD body mass index of 26.9 ± 4.4 kg/m. Images were reviewed by 2 independent readers in a blinded, randomized fashion. Hounsfield unit, noise, and contrast-to-noise ratio (CNR) values were calculated for each reconstruction algorithm for further comparison. Phantom evaluation of low-contrast detectability (LCD) and high-contrast resolution was performed. Adaptive statistical iterative reconstruction-V 30%, ASIR-V 60%, and ASIR 80% were generally superior qualitatively compared with ASIR-V 90%, Veo 3.0, and FBP (P ASIR-V 60% with respective CNR values of 5.54 ± 2.39, 8.78 ± 3.15, and 3.49 ± 1.77 (P ASIR 80% had the best and worst spatial resolution, respectively. Adaptive statistical iterative reconstruction-V 30% and ASIR-V 60% provided the best combination of qualitative and quantitative performance. Adaptive statistical iterative reconstruction 80% was equivalent qualitatively, but demonstrated inferior spatial resolution and LCD.

Improvement of mesh recolonization in abdominal wall reconstruction with adipose vs. bone marrow mesenchymal stem cells in a rodent model.

Science.gov (United States)

van Steenberghe, M; Schubert, T; Guiot, Y; Goebbels, R M; Gianello, P

2017-08-01

Reconstruction of muscle defects remains a challenge. Our work assessed the potential of an engineered construct made of a human acellular collagen matrix (HACM) seeded with porcine mesenchymal stem cells (MSCs) to reconstruct abdominal wall muscle defects in a rodent model. This study compared 2 sources of MSCs (bone-marrow, BMSCs, and adipose, ASCs) in vitro and in vivo for parietal defect reconstruction. Cellular viability and growth factor release (VEGF, FGF-Beta, HGF, IGF-1, TGF-Beta) were investigated under normoxic/hypoxic culture conditions. Processed and recellularized HACMs were mechanically assessed. The construct was tested in vivo in full thickness abdominal wall defect treated with HACM alone vs. HACM+ASCs or BMSCs (n=14). Tissue remodeling was studied at day 30 for neo-angiogenesis and muscular reconstruction. A significantly lower secretion of IGF was observed with ASCs vs. BMSCs under hypoxic conditions (-97.6%, p<0.005) whereas significantly higher VEGF/FGF secretions were found with ASCs (+92%, p<0.001 and +72%, p<0.05, respectively). Processing and recellularization did not impair the mechanical properties of the HACM. In vivo, angiogenesis and muscle healing were significantly improved by the HACM+ASCs in comparison to BMSCs (p<0.05) at day 30. A composite graft made of an HACM seeded with ASCs can improve muscle repair by specific growth factor release in hypoxic conditions and by in vivo remodeling (neo-angiogenesis/graft integration) while maintaining mechanical properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Intercalation and controlled release properties of vitamin C intercalated layered double hydroxide

Energy Technology Data Exchange (ETDEWEB)

Gao, Xiaorui, E-mail: gxr_1320@sina.com [College of Science, Hebei University of Engineering, Handan 056038 (China); School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA (United Kingdom); Lei, Lixu [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); O' Hare, Dermot [Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA (United Kingdom); Xie, Juan [College of Science, Hebei University of Engineering, Handan 056038 (China); Gao, Pengran [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Chang, Tao [College of Science, Hebei University of Engineering, Handan 056038 (China)

2013-07-15

Two drug-inorganic composites involving vitamin C (VC) intercalated in Mg–Al and Mg–Fe layered double hydroxides (LDHs) have been synthesized by the calcination–rehydration (reconstruction) method. Powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), and UV–vis absorption spectroscopy indicate a successful intercalation of VC into the interlayer galleries of the LDH host. Studies of VC release from the LDHs in deionised water and in aqueous CO{sub 3}{sup 2−} solutions imply that Mg{sub 3}Al–VC LDH is a better controlled release system than Mg{sub 3}Fe–VC LDH. Analysis of the release profiles using a number of kinetic models suggests a solution-dependent release mechanism, and a diffusion-controlled deintercalation mechanism in deionised water, but an ion exchange process in CO{sub 3}{sup 2−} solution. - Graphical abstract: Vitamin C anions have been intercalated in the interlayer space of layered double hydroxide and released in CO{sub 3}{sup 2−} solution and deionised water. - Highlights: • Vitamin C intercalated Mg–Al and Mg–Fe layered double hydroxides were prepared. • Release property of vitamin C in aqueous CO{sub 3}{sup 2−} solution is better. • Avrami-Erofe’ev and first-order models provide better fit for release results. • Diffusion-controlled and ion exchange processes occur in deionised water. • An ion exchange process occurs in CO{sub 3}{sup 2−} solution.

Image Reconstruction. Chapter 13

Energy Technology Data Exchange (ETDEWEB)

Nuyts, J. [Department of Nuclear Medicine and Medical Imaging Research Center, Katholieke Universiteit Leuven, Leuven (Belgium); Matej, S. [Medical Image Processing Group, Department of Radiology, University of Pennsylvania, Philadelphia, PA (United States)

2014-12-15

This chapter discusses how 2‑D or 3‑D images of tracer distribution can be reconstructed from a series of so-called projection images acquired with a gamma camera or a positron emission tomography (PET) system [13.1]. This is often called an ‘inverse problem’. The reconstruction is the inverse of the acquisition. The reconstruction is called an inverse problem because making software to compute the true tracer distribution from the acquired data turns out to be more difficult than the ‘forward’ direction, i.e. making software to simulate the acquisition. There are basically two approaches to image reconstruction: analytical reconstruction and iterative reconstruction. The analytical approach is based on mathematical inversion, yielding efficient, non-iterative reconstruction algorithms. In the iterative approach, the reconstruction problem is reduced to computing a finite number of image values from a finite number of measurements. That simplification enables the use of iterative instead of mathematical inversion. Iterative inversion tends to require more computer power, but it can cope with more complex (and hopefully more accurate) models of the acquisition process.

Hanford Environmental Dose Reconstruction Project monthly report

International Nuclear Information System (INIS)

McMakin, A.H., Cannon, S.D.; Finch, S.M.

1992-09-01

The objective of the Hanford Environmental Dose Reconstruction MDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in envirorunental pathways. epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering. radiation dosimetry. and cultural anthropology. Included are appointed members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source Terms; Environmental Transport; Environmental Monitoring Data Demography, Food Consumption, and Agriculture; and Environmental Pathways and Dose Estimates

By land, sea, or air? A comparative analysis of cartel smuggling strategies

OpenAIRE

Harney, Sean M.

2017-01-01

Approved for public release; distribution is unlimited Cartels are known for their innovative smuggling techniques, across land, sea, or air, which allow them to clandestinely transport drugs across any point of entry into the United States. With this in mind, it is worth asking: why do cartels choose a certain drug smuggling technique over another, which domain is more commonly used and potentially more successful, and what sorts of structural changes would it take to shift from one metho...

Coordinate reconstruction using box reconstruction and projection of X-ray photo

International Nuclear Information System (INIS)

Achmad Suntoro

2011-01-01

Some mathematical formula have been derived for a process of reconstruction to define the coordinate of any point relative to a pre set coordinate system. The process of reconstruction uses a reconstruction box in which each edge's length of the box is known, each top-bottom face and left-right face of the box having a cross marker, and the top face and the right face of the box as plane projections by X-ray source in perspective projection -system. Using the data of the two X-ray projection images, any point inside the reconstruction box, as long as its projection is recorded in the two photos, will be determined its coordinate relative to the midpoint of the reconstruction box as the central point coordinates. (author)

Segmentation-DrivenTomographic Reconstruction

DEFF Research Database (Denmark)

Kongskov, Rasmus Dalgas

such that the segmentation subsequently can be carried out by use of a simple segmentation method, for instance just a thresholding method. We tested the advantages of going from a two-stage reconstruction method to a one stage segmentation-driven reconstruction method for the phase contrast tomography reconstruction......The tomographic reconstruction problem is concerned with creating a model of the interior of an object from some measured data, typically projections of the object. After reconstructing an object it is often desired to segment it, either automatically or manually. For computed tomography (CT...

Vaginal reconstruction

International Nuclear Information System (INIS)

Lesavoy, M.A.

1985-01-01

Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients

Estimation of 1945 to 1957 food consumption. Hanford Environmental Dose Reconstruction Project: Draft

Energy Technology Data Exchange (ETDEWEB)

Anderson, D.M.; Bates, D.J.; Marsh, T.L.

1993-03-01

This report details the methods used and the results of the study on the estimated historic levels of food consumption by individuals in the Hanford Environmental Dose Reconstruction (HEDR) study area from 1945--1957. This period includes the time of highest releases from Hanford and is the period for which data are being collected in the Hanford Thyroid Disease Study. These estimates provide the food-consumption inputs for the HEDR database of individual diets. This database will be an input file in the Hanford Environmental Dose Reconstruction Integrated Code (HEDRIC) computer model that will be used to calculate the radiation dose. The report focuses on fresh milk, eggs, lettuce, and spinach. These foods were chosen because they have been found to be significant contributors to radiation dose based on the Technical Steering Panel dose decision level.

Oxygen-induced restructuring with release of gold atoms from Au(111)

International Nuclear Information System (INIS)

Min, B.K.; Deng, X.; Schalek, R.; Pinnaduwage, D.; Friend, C.M.

2005-01-01

Adsorption of oxygen atoms, achieved via electron-induced dissociation of nitrogen dioxide, induces restructuring of the 'herringbone' to a striped, soliton-wall structure accompanied by release of gold from the 'elbows' in the herringbone structure. The number density of 'elbows' (dislocations corresponding to a change in direction of the reconstruction) decreases as a function of increasing atomic oxygen coverage while the long range order observed in low energy electron diffraction (LEED) changes from (√(3)x22)-rec. to (1x22) in the limit of saturation coverage. Small islands and serrated step edges were formed due to the release of gold atoms from elbow sites of Au(111). The overall structural change of the Au(111) surface may result from the reduction of anisotropy related to the tensile stress relief of the Au(111) surface by oxygen atoms

Breast Reconstruction After Mastectomy

Science.gov (United States)

... Cancer Prevention Genetics of Breast & Gynecologic Cancers Breast Cancer Screening Research Breast Reconstruction After Mastectomy On This Page What is breast reconstruction? How do surgeons use implants to reconstruct a woman’s breast? How do surgeons ...

3D reconstruction of microvascular flow phantoms with hybrid imaging modalities

Science.gov (United States)

Lin, Jingying; Hsiung, Kevin; Ritenour, Russell; Golzarian, Jafar

2011-03-01

Microvascular flow phantoms were built to aid the development of a hemodynamic simulation model for treating hepatocelluar carcinoma. The goal is to predict the blood flow routing for embolotherapy planning. Embolization is to deliver agents (e.g. microspheres) to the vicinity of the tumor to obstruct blood supply and nutrients to the tumor, targeting into 30 - 40 μm arterioles. Due to the size of the catheter, it has to release microspheres at an upper stream location, which may not localize the blocking effect. Accurate anatomical descriptions of microvasculature will help to conduct a reliable simulation and prepare a successful embolization strategy. Modern imaging devices can generate 3D reconstructions with ease. However, with a fixed detector size, larger field of view yields lower resolution. Clinical CT images can't be used to measure micro vessel dimensions, while micro-CT requires more acquisitions to reconstruct larger vessels. A multi-tiered, montage 3D reconstruction method with hybrid-modality imagery is devised to minimize the reconstruction effort. Regular CT is used for larger vessels and micro-CT is used for micro vessels. The montage approach aims to stitch up images with different resolutions and orientations. A resolution-adaptable 3D image registration is developed to assemble the images. We have created vessel phantoms that consist of several tiers of bifurcating polymer tubes in reducing diameters, down to 25 μm. No previous work of physical flow phantom has ventured into this small scale. Overlapping phantom images acquired from clinical CT and micro-CT are used to verify the image registration fidelity.

Evidence-Based ACL Reconstruction

Directory of Open Access Journals (Sweden)

E. Carlos RODRIGUEZ-MERCHAN

2015-01-01

Full Text Available There is controversy in the literature regarding a number of topics related to anterior cruciate ligament (ACLreconstruction. The purpose of this article is to answer the following questions: 1 Bone patellar tendon bone (BPTB reconstruction or hamstring reconstruction (HR; 2 Double bundle or single bundle; 3 Allograft or authograft; 4 Early or late reconstruction; 5 Rate of return to sports after ACL reconstruction; 6 Rate of osteoarthritis after ACL reconstruction. A Cochrane Library and PubMed (MEDLINE search of systematic reviews and meta-analysis related to ACL reconstruction was performed. The key words were: ACL reconstruction, systematic reviews and meta-analysis. The main criteria for selection were that the articles were systematic reviews and meta-analysesfocused on the aforementioned questions. Sixty-nine articles were found, but only 26 were selected and reviewed because they had a high grade (I-II of evidence. BPTB-R was associated with better postoperative knee stability but with a higher rate of morbidity. However, the results of both procedures in terms of functional outcome in the long-term were similar. The double-bundle ACL reconstruction technique showed better outcomes in rotational laxity, although functional recovery was similar between single-bundle and double-bundle. Autograft yielded better results than allograft. There was no difference between early and delayed reconstruction. 82% of patients were able to return to some kind of sport participation. 28% of patients presented radiological signs of osteoarthritis with a follow-up of minimum 10 years.

Technical Note: FreeCT_ICD: An Open Source Implementation of a Model-Based Iterative Reconstruction Method using Coordinate Descent Optimization for CT Imaging Investigations.

Science.gov (United States)

Hoffman, John M; Noo, Frédéric; Young, Stefano; Hsieh, Scott S; McNitt-Gray, Michael

2018-06-01

To facilitate investigations into the impacts of acquisition and reconstruction parameters on quantitative imaging, radiomics and CAD using CT imaging, we previously released an open source implementation of a conventional weighted filtered backprojection reconstruction called FreeCT_wFBP. Our purpose was to extend that work by providing an open-source implementation of a model-based iterative reconstruction method using coordinate descent optimization, called FreeCT_ICD. Model-based iterative reconstruction offers the potential for substantial radiation dose reduction, but can impose substantial computational processing and storage requirements. FreeCT_ICD is an open source implementation of a model-based iterative reconstruction method that provides a reasonable tradeoff between these requirements. This was accomplished by adapting a previously proposed method that allows the system matrix to be stored with a reasonable memory requirement. The method amounts to describing the attenuation coefficient using rotating slices that follow the helical geometry. In the initially-proposed version, the rotating slices are themselves described using blobs. We have replaced this description by a unique model that relies on tri-linear interpolation together with the principles of Joseph's method. This model offers an improvement in memory requirement while still allowing highly accurate reconstruction for conventional CT geometries. The system matrix is stored column-wise and combined with an iterative coordinate descent (ICD) optimization. The result is FreeCT_ICD, which is a reconstruction program developed on the Linux platform using C++ libraries and the open source GNU GPL v2.0 license. The software is capable of reconstructing raw projection data of helical CT scans. In this work, the software has been described and evaluated by reconstructing datasets exported from a clinical scanner which consisted of an ACR accreditation phantom dataset and a clinical pediatric

Reconstruction of thyroid doses for the population of Belarus following the Chernobyl accident

International Nuclear Information System (INIS)

Gavrilin, Y.I.; Khrouch, V.T.; Shinkarev, S.M.; Minenko, V.F.; Drozdovich, V.V.; Ulanovsky, A.V.; Bouville, A.C.

1995-09-01

As a sequela to the large release of 131 I from the accident at the Chernobyl Nuclear Power Plant, an expected late effect is thyroid cancer, especially in children. In anticipation of this problem, hundreds of thousands of measurements of thyroid glands were made with survey meters. Much attention was also focused on measuring the deposition density of 137 Cs. The expectation was that the latter measurement could be a good surrogate for the deposition density of 131 I, so that ecological models could be used to reconstruct thyroid doses in locations where no direct measurements of thyroid activity were made. However, this assumption has been seriously questioned, and there is interest in a more suitable surrogate that can still be measured even nine years or more after the accident. The purpose of this paper is to discuss the reconstruction of thyroid doses for a case-control study of childhood-thyroid cancer that has just been concluded, to discuss the reconstruction of thyroid doses for a current cohort study of childhood-thyroid cancer, and to discuss the use of 129 I as a surrogate for the deposition density of 131 I

[Reconstructive methods after Fournier gangrene].

Science.gov (United States)

Wallner, C; Behr, B; Ring, A; Mikhail, B D; Lehnhardt, M; Daigeler, A

2016-04-01

Fournier's gangrene is a variant of the necrotizing fasciitis restricted to the perineal and genital region. It presents as an acute life-threatening disease and demands rapid surgical debridement, resulting in large soft tissue defects. Various reconstructive methods have to be applied to reconstitute functionality and aesthetics. The objective of this work is to identify different reconstructive methods in the literature and compare them to our current concepts for reconstructing defects caused by Fournier gangrene. Analysis of the current literature and our reconstructive methods on Fournier gangrene. The Fournier gangrene is an emergency requiring rapid, calculated antibiotic treatment and radical surgical debridement. After the acute phase of the disease, appropriate reconstructive methods are indicated. The planning of the reconstruction of the defect depends on many factors, especially functional and aesthetic demands. Scrotal reconstruction requires a higher aesthetic and functional reconstructive degree than perineal cutaneous wounds. In general, thorough wound hygiene, proper pre-operative planning, and careful consideration of the patient's demands are essential for successful reconstruction. In the literature, various methods for reconstruction after Fournier gangrene are described. Reconstruction with a flap is required for a good functional result in complex regions as the scrotum and penis, while cutaneous wounds can be managed through skin grafting. Patient compliance and tissue demand are crucial factors in the decision-making process.

Shaping the breast in secondary microsurgical breast reconstruction: single- vs. two-esthetic unit reconstruction.

Science.gov (United States)

Gravvanis, Andreas; Smith, Roger W

2010-10-01

The esthetic outcome is dictated essentially not only by the position, size, and shape of the reconstructed breast, but also by the extra scaring involved. In the present study, we conducted a visual analog scale survey to compare the esthetic outcome in delayed autologous breast reconstruction following two different abdominal flaps inset. Twenty-five patients had their reconstruction using the Single-esthetic Unit principle and were compared with 25 patients that their breast was reconstructed using the Two-Esthetic Unit principle. Photographic images were formulated to a PowerPoint presentation and cosmetic outcomes were assessed from 30 physicians, by means of a Questionnaire and a visual analog scale. Our data showed that the single-esthetic unit breast reconstruction presents significant advantages over the traditional two-esthetic units, due to inconspicuous flap reconstruction, better position of the inframammary fold, and more natural transition from native and reconstructed tissues. Moreover, patient self-evaluation of esthetic outcome and quality of life showed that single-esthetic unit reconstruction is associated with higher patient satisfaction, therefore should be considered the method of choice. © 2010 Wiley-Liss, Inc.

Our Clinical Experience in Lower Eyelid Reconstruction and Comparison of Reconstruction Techniques.

Directory of Open Access Journals (Sweden)

Erol Kesiktas

2011-03-01

Full Text Available Lower eyelid reconstruction after tumor resection or trauma is extremely important in order to obtain the protection of the globe and it requires extra care. The aim of this study is to evaluate the techniques that we use in lower eyelid reconstruction. Between the years of 1999-2009, a total of 23 patients who had lower eyelid defects due to tumor resection (21 patients or trauma (2 patients were reconstructed by the use of various flaps. Eleven of the patients were women and twelve of them were men. Average age was 60.7. For the reconstruction 13 Mustarde flap, 9 bipedicled Tripier flap, 1 Tenzel flap and 1 bipedicled infraorbital flaps were used. Average postoperative follow up interval was 35 months. (18-47 months. Flap necrosis, function loss in the lower lid were not experienced in any of the patients. Cosmetically satisfactory results were obtained. In lower eyelid reconstruction, the size of the defect and the amount of skin around must be carefully evaluated and should be considered while planning the reconstruction. [Cukurova Med J 2011; 36(1: 15-23

Assessing the effectiveness of massage therapy for bilateral cleft lip reconstruction scars.

Science.gov (United States)

McKay, Emilie

2014-06-01

Bilateral cleft lips occur when the bones that form the upper lip fail to fuse at birth. Surgical reconstruction creates scars, which may lead to the following impairments: adhesions, decreased oral range of motion, decreased strength of orbicularis oris muscle, and asymmetry of oral region leading to poor self-esteem. The purpose of this case study is to determine the effectiveness of massage therapy in its ability to improve these impairments. A five-week treatment plan consisting of fascial release, kneading, and intraoral techniques. Subjective information was assessed on two scales: restriction of scar and clients attitudes and acceptance of scar. Objective information was cataloged through photographs, a palpatory chart, and a self-created "Pen Test". Results included increase range of motion and strength, decrease restrictions (palpable and subjective), and increase of symmetry. Client's perceived confidence of scar and its appearance increased. The evidence suggests that massage therapy helped with the impairments associated with scars formed by bilateral cleft lip reconstruction.

Breast Reconstruction Following Cancer Treatment.

Science.gov (United States)

Gerber, Bernd; Marx, Mario; Untch, Michael; Faridi, Andree

2015-08-31

About 8000 breast reconstructions after mastectomy are per - formed in Germany each year. It has become more difficult to advise patients because of the wide variety of heterologous and autologous techniques that are now available and because of changes in the recommendations about radiotherapy. This article is based on a review of pertinent articles (2005-2014) that were retrieved by a selective search employing the search terms "mastectomy" and "breast reconstruction." The goal of reconstruction is to achieve an oncologically safe and aestically satisfactory result for the patient over the long term. Heterologous, i.e., implant-based, breast reconstruction (IBR) and autologous breast reconstruction (ABR) are complementary techniques. Immediate reconstruction preserves the skin of the breast and its natural form and prevents the psychological trauma associated with mastectomy. If post-mastectomy radiotherapy (PMRT) is not indicated, implant-based reconstruction with or without a net/acellular dermal matrix (ADM) is a common option. Complications such as seroma formation, infection, and explantation are significantly more common when an ADM is used (15.3% vs. 5.4% ). If PMRT is performed, then the complication rate of implant-based breast reconstruction is 1 to 48% ; in particular, Baker grade III/IV capsular fibrosis occurs in 7 to 22% of patients, and the prosthesis must be explanted in 9 to 41% . Primary or, preferably, secondary autologous reconstruction is an alternative. The results of ABR are more stable over the long term, but the operation is markedly more complex. Autologous breast reconstruction after PMRT does not increase the risk of serious complications (20.5% vs. 17.9% without radiotherapy). No randomized controlled trials have yet been conducted to compare the reconstructive techniques with each other. If radiotherapy will not be performed, immediate reconstruction with an implant is recommended. On the other hand, if post-mastectomy radiotherapy

Permutationally invariant state reconstruction

DEFF Research Database (Denmark)

Moroder, Tobias; Hyllus, Philipp; Tóth, Géza

2012-01-01

Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large-scale opti...... optimization, which has clear advantages regarding speed, control and accuracy in comparison to commonly employed numerical routines. First prototype implementations easily allow reconstruction of a state of 20 qubits in a few minutes on a standard computer.......-scale optimization problem, this is a major challenge in the design of scalable tomography schemes. Here we present an efficient state reconstruction scheme for permutationally invariant quantum state tomography. It works for all common state-of-the-art reconstruction principles, including, in particular, maximum...

Fast implementations of reconstruction-based scatter compensation in fully 3D SPECT image reconstruction

International Nuclear Information System (INIS)

Kadrmas, Dan J.; Karimi, Seemeen S.; Frey, Eric C.; Tsui, Benjamin M.W.

1998-01-01

Accurate scatter compensation in SPECT can be performed by modelling the scatter response function during the reconstruction process. This method is called reconstruction-based scatter compensation (RBSC). It has been shown that RBSC has a number of advantages over other methods of compensating for scatter, but using RBSC for fully 3D compensation has resulted in prohibitively long reconstruction times. In this work we propose two new methods that can be used in conjunction with existing methods to achieve marked reductions in RBSC reconstruction times. The first method, coarse-grid scatter modelling, significantly accelerates the scatter model by exploiting the fact that scatter is dominated by low-frequency information. The second method, intermittent RBSC, further accelerates the reconstruction process by limiting the number of iterations during which scatter is modelled. The fast implementations were evaluated using a Monte Carlo simulated experiment of the 3D MCAT phantom with 99m Tc tracer, and also using experimentally acquired data with 201 Tl tracer. Results indicated that these fast methods can reconstruct, with fully 3D compensation, images very similar to those obtained using standard RBSC methods, and in reconstruction times that are an order of magnitude shorter. Using these methods, fully 3D iterative reconstruction with RBSC can be performed well within the realm of clinically realistic times (under 10 minutes for 64x64x24 image reconstruction). (author)

Update on orbital reconstruction.

Science.gov (United States)

Chen, Chien-Tzung; Chen, Yu-Ray

2010-08-01

Orbital trauma is common and frequently complicated by ocular injuries. The recent literature on orbital fracture is analyzed with emphasis on epidemiological data assessment, surgical timing, method of approach and reconstruction materials. Computed tomographic (CT) scan has become a routine evaluation tool for orbital trauma, and mobile CT can be applied intraoperatively if necessary. Concomitant serious ocular injury should be carefully evaluated preoperatively. Patients presenting with nonresolving oculocardiac reflex, 'white-eyed' blowout fracture, or diplopia with a positive forced duction test and CT evidence of orbital tissue entrapment require early surgical repair. Otherwise, enophthalmos can be corrected by late surgery with a similar outcome to early surgery. The use of an endoscope-assisted approach for orbital reconstruction continues to grow, offering an alternative method. Advances in alloplastic materials have improved surgical outcome and shortened operating time. In this review of modern orbital reconstruction, several controversial issues such as surgical indication, surgical timing, method of approach and choice of reconstruction material are discussed. Preoperative fine-cut CT image and thorough ophthalmologic examination are key elements to determine surgical indications. The choice of surgical approach and reconstruction materials much depends on the surgeon's experience and the reconstruction area. Prefabricated alloplastic implants together with image software and stereolithographic models are significant advances that help to more accurately reconstruct the traumatized orbit. The recent evolution of orbit reconstruction improves functional and aesthetic results and minimizes surgical complications.

Incomplete projection reconstruction of computed tomography based on the modified discrete algebraic reconstruction technique

Science.gov (United States)

Yang, Fuqiang; Zhang, Dinghua; Huang, Kuidong; Gao, Zongzhao; Yang, YaFei

2018-02-01

Based on the discrete algebraic reconstruction technique (DART), this study aims to address and test a new improved algorithm applied to incomplete projection data to generate a high quality reconstruction image by reducing the artifacts and noise in computed tomography. For the incomplete projections, an augmented Lagrangian based on compressed sensing is first used in the initial reconstruction for segmentation of the DART to get higher contrast graphics for boundary and non-boundary pixels. Then, the block matching 3D filtering operator was used to suppress the noise and to improve the gray distribution of the reconstructed image. Finally, simulation studies on the polychromatic spectrum were performed to test the performance of the new algorithm. Study results show a significant improvement in the signal-to-noise ratios (SNRs) and average gradients (AGs) of the images reconstructed from incomplete data. The SNRs and AGs of the new images reconstructed by DART-ALBM were on average 30%-40% and 10% higher than the images reconstructed by DART algorithms. Since the improved DART-ALBM algorithm has a better robustness to limited-view reconstruction, which not only makes the edge of the image clear but also makes the gray distribution of non-boundary pixels better, it has the potential to improve image quality from incomplete projections or sparse projections.

BES-II fast data reconstruction

International Nuclear Information System (INIS)

Rong Gang; Zhang Jiawen; Guo Yiqing; Zhang Shaoqiang; Zhao Dixin

2002-01-01

The BES-II fast data reconstruction is reported. Based on PC FARM and/or a 'Distributed Clustered Linux PC System', BES-II fast data reconstruction system is set up. With this system the BES-II data can be fully reconstructed in about 20 minutes after data collection. It takes only 12 minutes to fully reconstruct 30000 events, collected with BES-II detector at BEPC Collider, with a P III-800 PC. The detector performance can be examined based on fully reconstructed data in about 20 minutes after data taking in the BES-II experiment

Prompt meningeal reconstruction mediated by oxygen-sensitive AKAP12 scaffolding protein after central nervous system injury

Science.gov (United States)

Cha, Jong-Ho; Wee, Hee-Jun; Seo, Ji Hae; Ahn, Bum Ju; Park, Ji-Hyeon; Yang, Jun-Mo; Lee, Sae-Won; Lee, Ok-Hee; Lee, Hyo-Jong; Gelman, Irwin H.; Arai, Ken; Lo, Eng H.; Kim, Kyu-Won

2015-01-01

The meninges forms a critical epithelial barrier, which protects the central nervous system (CNS), and therefore its prompt reconstruction after CNS injury is essential for reducing neuronal damage. Meningeal cells migrate into the lesion site after undergoing an epithelial-mesenchymal transition (EMT) and repair the impaired meninges. However, the molecular mechanisms of meningeal EMT remain largely undefined. Here we show that TGF-β1 and retinoic acid (RA) released from the meninges, together with oxygen tension, could constitute the mechanism for rapid meningeal reconstruction. AKAP12 is an effector of this mechanism, and its expression in meningeal cells is regulated by integrated upstream signals composed of TGF-β1, RA and oxygen tension. Functionally, AKAP12 modulates meningeal EMT by regulating the TGF-β1-non-Smad-SNAI1 signalling pathway. Collectively, TGF-β1, RA and oxygen tension can modulate the dynamic change in AKAP12 expression, causing prompt meningeal reconstruction after CNS injury by regulating the transition between the epithelial and mesenchymal states of meningeal cells. PMID:25229625

Excerpts from the introductory statement by IAEA Director General. IAEA Board of Governors, Vienna, 14 September 1998

International Nuclear Information System (INIS)

ElBaradei, M.

1998-01-01

The document contains excerpts from the Introductory Statement made by the Director General of the IAEA at the IAEA Board of Governors on 14 September 1998. The following aspects from the Agency's activity are presented: nuclear safety, technical co-operation programme, safeguards and verification, fissile material treaty, nuclear material released from the military sector, Agency's involvement in safeguards verification in the Democratic People's Republic of Korea (DPRK), Agency's inspections in Iraq in relation to its clandestine nuclear programme, and Agency's safeguards in the Middle East region

Application of micro beam PIXE to detection of titanium ion release from dental and orthopaedic implants

International Nuclear Information System (INIS)

Ektessabi, A.M.; Otsuka, T.; Tsuboi, Y.; Yokoyama, K.; Albrektsson, T.; Sennerby, L.; Johansson, C.

1994-01-01

In the past two decades the utilization of dental and orthopaedic implants in reconstructive surgery has been spread widely. Most of these implants are inserted in the corrosive environment of the human body for long periods of time. The level of dissolution, release, and transport of metal ions as a result of corrosion of these materials are not fully known at present. We report the results of application of micro ion beam PIXE spectroscopy to detect release of titanium from titanium and titanium alloy implants inserted in the tibiae of rabbits for three months. It was found that titanium ions could be detected in the surrounding tissues, with high precision, as a gradient from the implant surface and in higher amounts in the bone tissue as compared with the soft tissues. It is concluded that application of micro ion beam PIXE spectroscopy for detection of metal ion release, and distribution of the released material around the implants with high special resolution and accuracy may be used to further investigate the mechanism of metal release, and the relation between surface micromorphology and corrosion resistance of the implant materials. (author)

Bayesian inverse modeling and source location of an unintended 131I release in Europe in the fall of 2011

Science.gov (United States)

Tichý, Ondřej; Šmídl, Václav; Hofman, Radek; Šindelářová, Kateřina; Hýža, Miroslav; Stohl, Andreas

2017-10-01

In the fall of 2011, iodine-131 (131I) was detected at several radionuclide monitoring stations in central Europe. After investigation, the International Atomic Energy Agency (IAEA) was informed by Hungarian authorities that 131I was released from the Institute of Isotopes Ltd. in Budapest, Hungary. It was reported that a total activity of 342 GBq of 131I was emitted between 8 September and 16 November 2011. In this study, we use the ambient concentration measurements of 131I to determine the location of the release as well as its magnitude and temporal variation. As the location of the release and an estimate of the source strength became eventually known, this accident represents a realistic test case for inversion models. For our source reconstruction, we use no prior knowledge. Instead, we estimate the source location and emission variation using only the available 131I measurements. Subsequently, we use the partial information about the source term available from the Hungarian authorities for validation of our results. For the source determination, we first perform backward runs of atmospheric transport models and obtain source-receptor sensitivity (SRS) matrices for each grid cell of our study domain. We use two dispersion models, FLEXPART and Hysplit, driven with meteorological analysis data from the global forecast system (GFS) and from European Centre for Medium-range Weather Forecasts (ECMWF) weather forecast models. Second, we use a recently developed inverse method, least-squares with adaptive prior covariance (LS-APC), to determine the 131I emissions and their temporal variation from the measurements and computed SRS matrices. For each grid cell of our simulation domain, we evaluate the probability that the release was generated in that cell using Bayesian model selection. The model selection procedure also provides information about the most suitable dispersion model for the source term reconstruction. Third, we select the most probable location of

Bayesian inverse modeling and source location of an unintended 131I release in Europe in the fall of 2011

Directory of Open Access Journals (Sweden)

O. Tichý

2017-10-01

Full Text Available In the fall of 2011, iodine-131 (131I was detected at several radionuclide monitoring stations in central Europe. After investigation, the International Atomic Energy Agency (IAEA was informed by Hungarian authorities that 131I was released from the Institute of Isotopes Ltd. in Budapest, Hungary. It was reported that a total activity of 342 GBq of 131I was emitted between 8 September and 16 November 2011. In this study, we use the ambient concentration measurements of 131I to determine the location of the release as well as its magnitude and temporal variation. As the location of the release and an estimate of the source strength became eventually known, this accident represents a realistic test case for inversion models. For our source reconstruction, we use no prior knowledge. Instead, we estimate the source location and emission variation using only the available 131I measurements. Subsequently, we use the partial information about the source term available from the Hungarian authorities for validation of our results. For the source determination, we first perform backward runs of atmospheric transport models and obtain source-receptor sensitivity (SRS matrices for each grid cell of our study domain. We use two dispersion models, FLEXPART and Hysplit, driven with meteorological analysis data from the global forecast system (GFS and from European Centre for Medium-range Weather Forecasts (ECMWF weather forecast models. Second, we use a recently developed inverse method, least-squares with adaptive prior covariance (LS-APC, to determine the 131I emissions and their temporal variation from the measurements and computed SRS matrices. For each grid cell of our simulation domain, we evaluate the probability that the release was generated in that cell using Bayesian model selection. The model selection procedure also provides information about the most suitable dispersion model for the source term reconstruction. Third, we select the most

Selection of dominant radionuclides for Phase 1 of the Hanford Environmental Dose Reconstruction Project

Energy Technology Data Exchange (ETDEWEB)

Napier, B.A.

1991-07-01

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that individuals could have received as a result of emissions from nuclear operations at Hanford since their inception in 1944. A vital step in the estimation of radiation doses is the determination of the source term,'' that is, the quantities of radionuclides that were released to the environment from the various Hanford operations. Hanford operations have at various times involved hundreds of different radionuclides, some in relatively large quantities. Those radionuclides present in the largest quantities, although significant from an operational handling point of view, may not necessarily have been those of greatest concern for offsite radiation dose. This report documents the selection of the dominant radionuclides (those that may have resulted in the largest portion of the received doses) in the source term for Phase 1 of the HEDR Project, that is, for atmospheric releases from 1944 through 1947 and for surface water releases from 1964 through 1966. 15 refs., 3 figs., 10 tabs.

Hybrid spectral CT reconstruction.

Directory of Open Access Journals (Sweden)

Darin P Clark

Full Text Available Current photon counting x-ray detector (PCD technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID. In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM. Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with

Hybrid spectral CT reconstruction

Science.gov (United States)

Clark, Darin P.

2017-01-01

Current photon counting x-ray detector (PCD) technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID). In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM). Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with a spectral

Tomographic reconstruction by using FPSIRT (Fast Particle System Iterative Reconstruction Technique)

Energy Technology Data Exchange (ETDEWEB)

Moreira, Icaro Valgueiro M.; Melo, Silvio de Barros; Dantas, Carlos; Lima, Emerson Alexandre; Silva, Ricardo Martins; Cardoso, Halisson Alberdan C., E-mail: ivmm@cin.ufpe.br, E-mail: sbm@cin.ufpe.br, E-mail: rmas@cin.ufpe.br, E-mail: hacc@cin.ufpe.br, E-mail: ccd@ufpe.br, E-mail: eal@cin.ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

2015-07-01

The PSIRT (Particle System Iterative Reconstruction Technique) is a method of tomographic image reconstruction primarily designed to work with configurations suitable for industrial applications. A particle system is an optimization technique inspired in real physical systems that associates to the reconstructing material a set of particles with certain physical features, subject to a force eld, which can produce movement. The system constantly updates the set of particles by repositioning them in such a way as to approach the equilibrium. The elastic potential along a trajectory is a function of the difference between the attenuation coefficient in the current configuration and the corresponding input data. PSIRT has been successfully used to reconstruct simulated and real objects subject to sets of parallel and fanbeam lines in different angles, representing typical gamma-ray tomographic arrangements. One of PSIRT's limitation was its performance, too slow for real time scenarios. In this work, it is presented a reformulation in PSIRT's computational model, which is able to grant the new algorithm, the FPSIRT - Fast System Iterative Reconstruction Technique, a performance up to 200-time faster than PSIRT's. In this work a comparison of their application to real and simulated data from the HSGT, High Speed Gamma Tomograph, is presented. (author)

Tomographic reconstruction by using FPSIRT (Fast Particle System Iterative Reconstruction Technique)

International Nuclear Information System (INIS)

Moreira, Icaro Valgueiro M.; Melo, Silvio de Barros; Dantas, Carlos; Lima, Emerson Alexandre; Silva, Ricardo Martins; Cardoso, Halisson Alberdan C.

2015-01-01

The PSIRT (Particle System Iterative Reconstruction Technique) is a method of tomographic image reconstruction primarily designed to work with configurations suitable for industrial applications. A particle system is an optimization technique inspired in real physical systems that associates to the reconstructing material a set of particles with certain physical features, subject to a force eld, which can produce movement. The system constantly updates the set of particles by repositioning them in such a way as to approach the equilibrium. The elastic potential along a trajectory is a function of the difference between the attenuation coefficient in the current configuration and the corresponding input data. PSIRT has been successfully used to reconstruct simulated and real objects subject to sets of parallel and fanbeam lines in different angles, representing typical gamma-ray tomographic arrangements. One of PSIRT's limitation was its performance, too slow for real time scenarios. In this work, it is presented a reformulation in PSIRT's computational model, which is able to grant the new algorithm, the FPSIRT - Fast System Iterative Reconstruction Technique, a performance up to 200-time faster than PSIRT's. In this work a comparison of their application to real and simulated data from the HSGT, High Speed Gamma Tomograph, is presented. (author)

Reconstructing Tritium Exposure Using Tree Rings at Lawrence Berkeley National Laboratory, California

Science.gov (United States)

LOVE, ADAM H.; HUNT, JAMES R.; KNEZOVICH, JOHN P.

2010-01-01

Annual tritium exposures were reconstructed using tree cores from Pinus jeffreyi and Eucalyptus globulus near a tritiated water vapor release stack. Both tritium (3H) and carbon-14 (14C) from the wood were measured from milligram samples using accelerator mass spectrometry. Because the annual nature of the eucalyptus tree rings was in doubt, 14C measurements provided growth rates used to estimate the age for 3H determinations. A 30-yr comparison of organically bound tritium (OBT) levels to reported 3H release data is achieved using OBT measurements from three trees near the stack. The annual average 3H, determined from atmospheric water vapor monitoring stations, is comparable to the OBT in proximal trees. For situations without adequate historical monitoring data, this measurement-based historical assessment provides the only independent means of assessing exposure as compared to fate and transport models that require prior knowledge of environmental conditions and 3H discharge patterns. PMID:14572081

Simulation of atmospheric krypton-85 transport to assess the detectability of clandestine nuclear reprocessing

Energy Technology Data Exchange (ETDEWEB)

Ross, Jens Ole

2010-02-02

The radioactive noble gas krypton-85 is released into the atmosphere during reprocessing of spent nuclear fuel or irradiated breeding targets. This is a necessary step for plutonium separation. Therefore the {sup 85}Kr signature of reprocessing could possibly be used for the detection of undeclared nuclear facilities producing nuclear weaponusable material. The {sup 85}Kr content of the atmosphere has grown over the last decades as the emissions from military and civilian nuclear industry could not be compensated by the decay with a half-life of 10.76 years. In this study, the global {sup 85}Kr background distribution due to emissions of known reprocessing facilities for the period from 1971 until 2006 was simulated using the atmospheric general circulation model ECHAM5 applying the newest available annual emission data. The convective tracer transport scheme and the operator splitting for the physical calculations in the model were modified in order to guarantee physically correct results for tracer point sources, in particular non negative concentrations. An on-line routine controlling the {sup 85}Kr -budget in the model enforced exact mass conservation. The results of the simulation were evaluated by extensive comparison with measurements performed by the German Federal Office for Radiation Protection with very good agreement at most observation sites except those in the direct vicinity of {sup 85}Kr sources. Of particular interest for the {sup 85}Kr detection potential was the variability of {sup 85}Kr background concentrations which was evaluated for the first time in a global model. In addition, the interhemispheric transport as simulated by ECHAM5 was analyzed using a two-box model providing a mean exchange time of τ {sub ex} = 10.5 months. The analysis of τ{sub ex} over simulated 35 years indicates that in years with strong South Asian or African Monsoon the interhemispheric transport is faster during the monsoon season. A correlation analysis of

Medial Patellofemoral Ligament Reconstruction Using the Hamstring Tendon for Patellofemoral Joint Instability in an 81-Year-Old Female.

Science.gov (United States)

Takahashi, Tsuneari; Takeshita, Katsushi

2017-01-01

Chronic patellofemoral instability occurs mainly in adolescent females and can also be induced by medial patellofemoral ligament (MPFL) injury. There are no case reports of MPFL reconstruction for chronic patellofemoral instability due to MPFL injury in aged populations. 81-year-old female presented with left knee pain, giving way, and patellar instability while climbing stairs, which continued for 18 months. Patellar apprehension test was positive, and roentgenogram showed lateral patellar subluxation. Conservative therapy was not successful; hence, we performed a lateral release and MPFL reconstruction surgery. After arthroscopic lateral release, the hamstring tendon was harvested, and a graft composite made of doubled hamstring tendon and polyester tape with a suspensory fixation device was prepared. Then, a femoral bone tunnel was constructed in a socket shape at the anatomical footprint of the MPFL. The graft was passed through the femoral tunnel, and free ends of the graft composite were sutured to the periosteum of the patella, using two suture anchors at 60° of knee flexion with patellar reduction. Physiotherapy was gradually started using a patella-stabilizing orthosis on the first postoperative day. Her Kujala score improved from 66 to 97 points, and Barthel index score improved from 70 to 100 points at 1 year after surgery. She neither developed patellofemoral joint OA nor had any recurrence of symptoms at the 5-year postoperative follow up. MPFL reconstruction using the hamstring tendon is an effective procedure for patients with chronic patellofemoral instability even after the age of 80 years.

Phase 1 of the Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

1991-08-01

The work described in this report was prompted by the public's concern about potential effect from the radioactive materials released from the Hanford Site. The Hanford Environmental Dose Reconstruction (HEDR) Project was established to estimate radiation dose the public might have received from the Hanford Site since 1944, when facilities began operating. Phase 1 of the HEDR Project is a ''pilot'' or ''demonstration'' phase. The objectives of this initial phase were to determine whether enough historical information could be found or reconstructed to be used for dose estimation and develop and test conceptual and computational models for calculating credible dose estimates. Preliminary estimates of radiation doses were produced in Phase 1 because they are needed to achieve these objectives. The reader is cautioned that the dose estimates provided in this and other Phase 1 HEDR reports are preliminary. As the HEDR Project continues, the dose estimates will change for at least three reasons: more complete input information for models will be developed; the models themselves will be refined; and the size and shape of the geographic study area will change. This is one of three draft reports that summarize the first phase of the four-phased HEDR Project. This, the Summary Report, is directed to readers who want a general understanding of the Phase 1 work and preliminary dose estimates. The two other reports -- the Air Pathway Report and the Columbia River Pathway Report -- are for readers who understand the radiation dose assessment process and want to see more technical detail. Detailed descriptions of the dose reconstruction process are available in more than 20 supporting reports listed in Appendix A. 32 refs., 46 figs

The evolving breast reconstruction

DEFF Research Database (Denmark)

Thomsen, Jørn Bo; Gunnarsson, Gudjon Leifur

2014-01-01

The aim of this editorial is to give an update on the use of the propeller thoracodorsal artery perforator flap (TAP/TDAP-flap) within the field of breast reconstruction. The TAP-flap can be dissected by a combined use of a monopolar cautery and a scalpel. Microsurgical instruments are generally...... not needed. The propeller TAP-flap can be designed in different ways, three of these have been published: (I) an oblique upwards design; (II) a horizontal design; (III) an oblique downward design. The latissimus dorsi-flap is a good and reliable option for breast reconstruction, but has been criticized...... for oncoplastic and reconstructive breast surgery and will certainly become an invaluable addition to breast reconstructive methods....

Reconstructing see-saw models

International Nuclear Information System (INIS)

Ibarra, Alejandro

2007-01-01

In this talk we discuss the prospects to reconstruct the high-energy see-saw Lagrangian from low energy experiments in supersymmetric scenarios. We show that the model with three right-handed neutrinos could be reconstructed in theory, but not in practice. Then, we discuss the prospects to reconstruct the model with two right-handed neutrinos, which is the minimal see-saw model able to accommodate neutrino observations. We identify the relevant processes to achieve this goal, and comment on the sensitivity of future experiments to them. We find the prospects much more promising and we emphasize in particular the importance of the observation of rare leptonic decays for the reconstruction of the right-handed neutrino masses

Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

Energy Technology Data Exchange (ETDEWEB)

Shehata, M.S. [Mechanical Engineering Technology Department, Higher Institute of Technology, Banha University, 4Zagalol Street, Benha, Galubia 1235 Z (Egypt)

2010-12-15

An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the source of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio {gamma}(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating {gamma}(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio {gamma}(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and

Cylinder pressure, performance parameters, heat release, specific heats ratio and duration of combustion for spark ignition engine

International Nuclear Information System (INIS)

Shehata, M.S.

2010-01-01

An experimental work were conducted for investigating cylinder pressure, performance parameters, heat release, specific heat ratio and duration of combustion for multi cylinder spark ignition engine (SIE). Ccylinder pressure was measured for gasoline, kerosene and Liquefied Petroleum Gases (LPG) separately as a fuel for SIE. Fast Fourier Transformations (FFT) was used to cylinder pressure data transform from time domain into frequency domain to develop empirical correlation for calculating cylinder pressures at different engine speeds and different fuels. In addition, Inverse Fast Fourier Transformations (IFFT) was used to cylinder pressure reconstruct into time domain. The results gave good agreement between the measured cylinder pressure and the reconstructed cylinder pressure in time domain with different engine speeds and different fuels. The measured cylinder pressure and hydraulic dynamotor were the sours of data for calculating engine performance parameters. First law of thermodynamics and single zone heat release model with temperature dependant specific heat ratio γ(T) were the main tools for calculating heat release and heat transfer to cylinder walls. Third order empirical correlation for calculating γ(T) was one of the main gains of the present study. The correlation gave good agreement with other researchers with wide temperatures range. For kerosene, cylinder pressure is higher than for gasoline and LPG due to high volumetric efficiency where kerosene density (mass/volume ratio) is higher than gasoline and LPG. In addition, kerosene heating value is higher than gasoline that contributes in heat release rate and pressure increases. Duration of combustion for different engine speeds was determined using four different methods: (I) Mass fuel burnt, (II) Entropy change, (III) Temperature dependant specific heat ratio γ(T), and (IV) Logarithmic scale of (P and V). The duration of combustion for kerosene is smaller than for gasoline and LPG due to high

Pre-operative planning for mandibular reconstruction - A full digital planning workflow resulting in a patient specific reconstruction

Science.gov (United States)

2011-01-01

Objectives Reconstruction of large mandiblular defects following ablative oncologic surgery could be done by using vascularized bone transfer or, more often, primarily with simultaneous or delayed bone grafting, using load bearing reconstruction plates. Bending of these reconstruction plates is typically directed along the outer contour of the original mandible. Simultaneously or in a second operation vascularized or non-vascularized bone is fixed to the reconstruction plate. However, the prosthodontic-driven backward planning to ease bony reconstruction of the mandible in terms of dental rehabilitation using implant-retained overdentures might be an eligible solution. The purpose of this work was to develop, establish and clinically evaluate a novel 3D planning procedure for mandibular reconstruction. Materials and methods Three patients with tumors involving the mandible, which included squamous cell carcinoma in the floor of the mouth and keratocystic odontogenic tumor, were treated surgically by hemimandibulectomy. Results In primary alloplastic mandible reconstruction, shape and size of the reconstruction plate could be predefined and prebent prior to surgery. Clinical relevance This study provides modern treatment strategies for mandibular reconstruction. PMID:21968330

Reconstruction of emission coefficients for a non-axisymmetric coupling arc by algebraic reconstruction technique

International Nuclear Information System (INIS)

Zhang Guangjun; Xiong Jun; Gao Hongming; Wu Lin

2011-01-01

A preliminary investigation of tomographic reconstruction of an asymmetric arc plasma has been carried out. The objective of this work aims at reconstructing emission coefficients of a non-axisymmetric coupling arc from measured intensities by means of an algebraic reconstruction technique (ART). In order to define the optimal experimental scheme for good quality with limited views, the dependence of the reconstruction quality on three configurations (four, eight, ten projection angles) are presented and discussed via a displaced Gaussian model. Then, the emission coefficients of a free burning arc are reconstructed by the ART with the ten-view configuration and an Abel inversion, respectively, and good agreement is obtained. Finally, the emission coefficient profiles of the coupling arc are successfully achieved with the ten-view configuration. The results show that the distribution of emission coefficient for the coupling arc is different from centrosymmetric shape. The ART is perfectly suitable for reconstructing emission coefficients of the coupling arc with the ten-view configuration, proving the feasibility and utility of the ART to characterize an asymmetric arc.

Technical basis for dose reconstruction

International Nuclear Information System (INIS)

Anspaugh, L.R.

1996-01-01

The purpose of this paper is to consider two general topics: Technical considerations of why dose-reconstruction studies should or should not be performed and methods of dose reconstruction. The first topic is of general and growing interest as the number of dose-reconstruction studies increases, and one asks the question whether it is necessary to perform a dose reconstruction for virtually every site at which, for example, the Department of Energy (DOE) has operated a nuclear-related facility. And there is the broader question of how one might logically draw the line at performing or not performing dose-reconstruction (radiological and chemical) studies for virtually every industrial complex in the entire country. The second question is also of general interest. There is no single correct way to perform a dose-reconstruction study, and it is important not to follow blindly a single method to the point that cheaper, faster, more accurate, and more transparent methods might not be developed and applied. 90 refs., 4 tabs

Technical basis for dose reconstruction

International Nuclear Information System (INIS)

Anspaugh, L.R.

1996-01-01

The purpose of this paper is to consider two general topics: technical considerations of why dose-reconstruction studies should or should not be performed and methods of dose reconstruction. The first topic is of general and growing interest as the number of dose-reconstruction studies increases, and one asks the question whether it is necessary to perform a dose reconstruction for virtually every site at which, for example, the Department of Energy (DOE) has operated a nuclear-related facility. And there is the broader question of how one might logically draw the line at performing or not performing dose-reconstruction (radiological and chemical) studies for virtually every industrial complex in the entire country. The second question is also of general interest. There is no single correct way to perform a dose-reconstruction study, and it is important not to follow blindly a single method to the point that cheaper, faster, more accurate, and more transparent methods might not be developed and applied

Three-dimensional ICT reconstruction

International Nuclear Information System (INIS)

Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

2005-01-01

The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context, qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

Three-dimensional ICT reconstruction

International Nuclear Information System (INIS)

Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

2004-01-01

The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by order, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

Building credibility in public studies: Lessons learned from the Hanford environmental Dose Reconstruction project may apply to all public studies

International Nuclear Information System (INIS)

Till, J.E.

1995-01-01

This article describes the process by which the author came to recognize the importance of openness to the public in environmental studies, during the Hanford Environmental Dose Reconstruction Project. Using the Dose reconstruction public involvement, the article goes on to describe a general guide to the construction of a new, positive framework for conducting future public studies. The steps include the following: putting the public in the study; building credibility into a public study (1 -search for proof in historical records; 2-define the domain and the exposed population; 3-characterize the material released; 4-identify key materials, pathways and receptors; 5-encouraging public participation; 6 -explaining the meaning of the results) and reconciling scientific and public issues

Building credibility in public studies: Lessons learned from the Hanford environmental Dose Reconstruction project may apply to all public studies

Energy Technology Data Exchange (ETDEWEB)

Till, J.E. [Radiological Assessment Corp., Neeses, SC (United States)

1995-09-01

This article describes the process by which the author came to recognize the importance of openness to the public in environmental studies, during the Hanford Environmental Dose Reconstruction Project. Using the Dose reconstruction public involvement, the article goes on to describe a general guide to the construction of a new, positive framework for conducting future public studies. The steps include the following: putting the public in the study; building credibility into a public study (1 -search for proof in historical records; 2-define the domain and the exposed population; 3-characterize the material released; 4-identify key materials, pathways and receptors; 5-encouraging public participation; 6 -explaining the meaning of the results) and reconciling scientific and public issues.

Red, Straight, no bends: primordial power spectrum reconstruction from CMB and large-scale structure

Energy Technology Data Exchange (ETDEWEB)

Ravenni, Andrea [Dipartimento di Fisica e Astronomia ' ' G. Galilei' ' , Università degli Studi di Padova, via Marzolo 8, I-35131, Padova (Italy); Verde, Licia; Cuesta, Antonio J., E-mail: andrea.ravenni@pd.infn.it, E-mail: liciaverde@icc.ub.edu, E-mail: ajcuesta@icc.ub.edu [Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, E08028 Barcelona (Spain)

2016-08-01

We present a minimally parametric, model independent reconstruction of the shape of the primordial power spectrum. Our smoothing spline technique is well-suited to search for smooth features such as deviations from scale invariance, and deviations from a power law such as running of the spectral index or small-scale power suppression. We use a comprehensive set of the state-of the art cosmological data: Planck observations of the temperature and polarisation anisotropies of the cosmic microwave background, WiggleZ and Sloan Digital Sky Survey Data Release 7 galaxy power spectra and the Canada-France-Hawaii Lensing Survey correlation function. This reconstruction strongly supports the evidence for a power law primordial power spectrum with a red tilt and disfavours deviations from a power law power spectrum including small-scale power suppression such as that induced by significantly massive neutrinos. This offers a powerful confirmation of the inflationary paradigm, justifying the adoption of the inflationary prior in cosmological analyses.

Evidence on unusual way of cocaine smuggling: cocaine-polymethyl methacrylate (PMMA) solid solution--study of clandestine laboratory samples.

Science.gov (United States)

Gostic, T; Klemenc, S

2007-07-04

An abandoned clandestine laboratory was seized in Slovenia. All confiscated exhibits were analysed in a forensic laboratory, where the following analytical methods were applied: capillary gas chromatography coupled with mass spectrometry (GC-MS) combined also by solid-phase micro extraction (SPME) and pyrolysis (Py) technique, Fourier transform infrared spectrometry (FTIR) and scanning electron microscopy with energy dispersive X-ray detector (SEM-EDX). The most interesting analytical findings can be summarised as follows: at the crime scene some plastic pieces, which contained cocaine dissolved (as solid solution) in polymethyl methacrylate-plexiglass (PMMA), were found. The highest cocaine concentration measured in the plastic sample was about 15% by weight. Two larger lumps of material (12 and 3 kg) were composed mainly of PMMA and CaCO3 and contained only 0.4 and 0.5% of cocaine, respectively. As for the low cocaine concentration, we assume that those two lumps of material represent discarded waste product--residue after the isolation of cocaine from plastic. Higher quantities of pure solvents (41 l) and solvent mixtures (87 l) were seized. We identified three types of pure solvents (acetone, gasoline and benzine) and two different types of solvent mixtures (benzine/acetone and gasoline/acetone). The total seized volume (87 l) of solvent mixtures holds approximately 395 g of solid residue formed mainly of PMMA and cocaine. Obviously solvent mixtures were used for isolation of cocaine from the plastic. Small quantities of relatively pure cocaine base were identified on different objects. There were two cotton sheets, most probably used for filtration. One sheet had traces of cocaine base (76% purity) on the surface, while cocaine in hydrochloride form (96%) was identified on the other sheet. GC-MS analyses of micro traces isolated from analytical balances showed the presence of cocaine and some common adulterants: phenacetine, lidocaine and procaine. A cocaine

Investigation of various reconstruction parameters for algebraic reconstruction technique in a newly developed chest digital tomosynthesis

International Nuclear Information System (INIS)

Lee, H.; Choi, S.; Kim, Y.-S.; Park, H.-S.; Seo, C.-W.; Kim, H.-J.; Lee, D.; Lee, Y.

2017-01-01

Chest digital tomosynthesis (CDT) is a promising new modality that provides 3D information by reconstructing limited projection views. CDT systems have been developed to improve the limitations of conventional radiography such as image degradation and low sensitivity. However, the development of reconstruction methods is challenging because of the limited projection views within various angular ranges. Optimization of reconstruction parameters for various reconsturction methods in CDT system also is needed. The purpose of this study was to investigate the feasibility of algebraic reconstruction technique (ART) method, and to evaluate the effect of the reconstruction parameters for our newly developed CDT system. We designed ART method with 41 projection views over an angular range of ±20°. To investigate the effect of reconstruction parameters, we measured the contrast-to-noise ratio (CNR), artifact spread function (ASF), and quality factor (QF) using LUNGMAN phantom included tumors. We found that the proper choice of reconstruction parameters such as relaxation parameter, initial guess, and number of iterations improved the quality of reconstructed images from the same projection views. Optimal values of ART relaxation parameter with uniform (UI) and back-projection (BP) initial guesses were 0.4 and 0.6, respectively. BP initial guess improved image quality in comparison with UI initial guess, in terms of providing a higher CNR and QF values with a faster speed. CNR and QF values improved with increasing number of iteration. Particularly, ART method with BP initial guess (when β = 0.6) after 3-terations provide satisfactory reconstructed image. In conclusion, the use of ART method with proper reconstruction parameters provided better image quality than FBP method as well as conventional radiography. These results indicated that the ART method with optimal reconstruction parameters could improve image quality for nodule detection using the CDT system.

Investigation of various reconstruction parameters for algebraic reconstruction technique in a newly developed chest digital tomosynthesis

Science.gov (United States)

Lee, H.; Choi, S.; Lee, D.; Kim, Y.-s.; Park, H.-S.; Lee, Y.; Seo, C.-W.; Kim, H.-J.

2017-08-01

Chest digital tomosynthesis (CDT) is a promising new modality that provides 3D information by reconstructing limited projection views. CDT systems have been developed to improve the limitations of conventional radiography such as image degradation and low sensitivity. However, the development of reconstruction methods is challenging because of the limited projection views within various angular ranges. Optimization of reconstruction parameters for various reconsturction methods in CDT system also is needed. The purpose of this study was to investigate the feasibility of algebraic reconstruction technique (ART) method, and to evaluate the effect of the reconstruction parameters for our newly developed CDT system. We designed ART method with 41 projection views over an angular range of ±20°. To investigate the effect of reconstruction parameters, we measured the contrast-to-noise ratio (CNR), artifact spread function (ASF), and quality factor (QF) using LUNGMAN phantom included tumors. We found that the proper choice of reconstruction parameters such as relaxation parameter, initial guess, and number of iterations improved the quality of reconstructed images from the same projection views. Optimal values of ART relaxation parameter with uniform (UI) and back-projection (BP) initial guesses were 0.4 and 0.6, respectively. BP initial guess improved image quality in comparison with UI initial guess, in terms of providing a higher CNR and QF values with a faster speed. CNR and QF values improved with increasing number of iteration. Particularly, ART method with BP initial guess (when β = 0.6) after 3-terations provide satisfactory reconstructed image. In conclusion, the use of ART method with proper reconstruction parameters provided better image quality than FBP method as well as conventional radiography. These results indicated that the ART method with optimal reconstruction parameters could improve image quality for nodule detection using the CDT system.

Entropy and transverse section reconstruction

International Nuclear Information System (INIS)

Gullberg, G.T.

1976-01-01

A new approach to the reconstruction of a transverse section using projection data from multiple views incorporates the concept of maximum entropy. The principle of maximizing information entropy embodies the assurance of minimizing bias or prejudice in the reconstruction. Using maximum entropy is a necessary condition for the reconstructed image. This entropy criterion is most appropriate for 3-D reconstruction of objects from projections where the system is underdetermined or the data are limited statistically. This is the case in nuclear medicine time limitations in patient studies do not yield sufficient projections

Breast reconstruction - natural tissue

Science.gov (United States)

... flap; TRAM; Latissimus muscle flap with a breast implant; DIEP flap; DIEAP flap; Gluteal free flap; Transverse upper gracilis flap; TUG; Mastectomy - breast reconstruction with natural tissue; Breast cancer - breast reconstruction with natural tissue

GDP Release Preferentially Occurs on the Phosphate Side in Heterotrimeric G-proteins

Science.gov (United States)

Louet, Maxime; Martinez, Jean; Floquet, Nicolas

2012-01-01

After extra-cellular stimulation of G-Protein Coupled Receptors (GPCRs), GDP/GTP exchange appears as the key, rate limiting step of the intracellular activation cycle of heterotrimeric G-proteins. Despite the availability of a large number of X-ray structures, the mechanism of GDP release out of heterotrimeric G-proteins still remains unknown at the molecular level. Starting from the available X-ray structure, extensive unconstrained/constrained molecular dynamics simulations were performed on the complete membrane-anchored Gi heterotrimer complexed to GDP, for a total simulation time overcoming 500 ns. By combining Targeted Molecular Dynamics (TMD) and free energy profiles reconstruction by umbrella sampling, our data suggest that the release of GDP was much more favored on its phosphate side. Interestingly, upon the forced extraction of GDP on this side, the whole protein encountered large, collective motions in perfect agreement with those we described previously including a domain to domain motion between the two ras-like and helical sub-domains of Gα. PMID:22829757

Jini service to reconstruct tomographic data

Science.gov (United States)

Knoll, Peter; Mirzaei, S.; Koriska, K.; Koehn, H.

2002-06-01

A number of imaging systems rely on the reconstruction of a 3- dimensional model from its projections through the process of computed tomography (CT). In medical imaging, for example magnetic resonance imaging (MRI), positron emission tomography (PET), and Single Computer Tomography (SPECT) acquire two-dimensional projections of a three dimensional projections of a three dimensional object. In order to calculate the 3-dimensional representation of the object, i.e. its voxel distribution, several reconstruction algorithms have been developed. Currently, mainly two reconstruct use: the filtered back projection(FBP) and iterative methods. Although the quality of iterative reconstructed SPECT slices is better than that of FBP slices, such iterative algorithms are rarely used for clinical routine studies because of their low availability and increased reconstruction time. We used Jini and a self-developed iterative reconstructions algorithm to design and implement a Jini reconstruction service. With this service, the physician selects the patient study from a database and a Jini client automatically discovers the registered Jini reconstruction services in the department's Intranet. After downloading the proxy object the this Jini service, the SPECT acquisition data are reconstructed. The resulting transaxial slices are visualized using a Jini slice viewer, which can be used for various imaging modalities.

Use of the Composite Pedicled Pectoralis Minor Flap after Resection of Soft Tissue Sarcoma in Reconstruction of the Glenohumeral Joint

Directory of Open Access Journals (Sweden)

Michiel A. J. van de Sande

2014-01-01

Full Text Available The surgical repair of an extensive anterior glenohumeral soft tissue defect is complicated by glenohumeral instability and subsequent significant functional deficit. This surgical note offers a relatively simple reconstruction of the anterior capsule and subscapularis muscle using a pectoralis minor pedicle flap. This reconstruction is supplemented with functional reconstruction of the anterior glenohumeral joint. A conventional deltopectoral approach is utilized and pectoralis minor is freed from its coracoid insertion, released, and mobilized without compromising the pedicle entering from the dorsum and inferior one-third of the muscle. The mobilized pectoralis minor vascular pedicle has sufficient length for the pectoralis minor to be transferred to provide coverage of the anterior shoulder joint even in full external rotation, providing anterior stability. To further improve glenohumeral stability and shoulder function, the pectoralis major muscle can be split with the clavicular part reinserted lateral to the bicipital groove onto the lesser tuberosity replacing subscapularis function while stabilising the glenohumeral joint.

BREAST RECONSTRUCTIONS AFTER BREAST CANCER TREATING

Directory of Open Access Journals (Sweden)

Erik Vrabič

2018-02-01

Full Text Available Background. Breasts are an important symbol of physical beauty, feminity, mothering and sexual desire through the entire history of mankind. Lost of the whole or part of the breast is functional and aesthetic disturbance for woman. It is understandable, that the woman, who is concerned over breast loss, is as appropriate as another person´s concern over the loss of a limb or other body part. Before the 1960, breast reconstruction was considered as a dangerous procedure and it was almost prohibited. Considering the psychological importance of the breast in modern society, the possibility of breast reconstruction for the woman about to undergo a mastectomy is a comforting alternative. We can perform breast reconstruction with autologous tissue (autologous reconstruction, with breast implants and combination of both methods. For autologous reconstruction we can use local tissue (local flaps, or tissue from distant parts of the body (free vascular tissue transfer. Tissue expansion must be performed first, in many cases of breast reconstructions with breast implants. Conclusions. Possibility of breast reconstruction made a big progress last 3 decades. Today we are able to reconstruct almost every defect of the breast and the entire breast. Breast reconstruction rise the quality of life for breast cancer patients. Breast reconstruction is a team work of experts from many medicine specialites. In Slovenia we can offer breast reconstruction for breast cancer patients in Ljubljana, where plastic surgeons from Clinical Department for Plastic Surgery and Burns cooperate with oncologic surgeons. Ten years ago a similar cooperation between plastic surgeons and surgeons of the Centre for Breast Diseases was established in Maribor.

Reconstruction of a ring applicator using CT imaging: impact of the reconstruction method and applicator orientation

International Nuclear Information System (INIS)

Hellebust, Taran Paulsen; Tanderup, Kari; Bergstrand, Eva Stabell; Knutsen, Bjoern Helge; Roeislien, Jo; Olsen, Dag Rune

2007-01-01

The purpose of this study is to investigate whether the method of applicator reconstruction and/or the applicator orientation influence the dose calculation to points around the applicator for brachytherapy of cervical cancer with CT-based treatment planning. A phantom, containing a fixed ring applicator set and six lead pellets representing dose points, was used. The phantom was CT scanned with the ring applicator at four different angles related to the image plane. In each scan the applicator was reconstructed by three methods: (1) direct reconstruction in each image (DR) (2) reconstruction in multiplanar reconstructed images (MPR) and (3) library plans, using pre-defined applicator geometry (LIB). The doses to the lead pellets were calculated. The relative standard deviation (SD) for all reconstruction methods was less than 3.7% in the dose points. The relative SD for the LIB method was significantly lower (p < 0.05) than for the DR and MPR methods for all but two points. All applicator orientations had similar dose calculation reproducibility. Using library plans for applicator reconstruction gives the most reproducible dose calculation. However, with restrictive guidelines for applicator reconstruction the uncertainties for all methods are low compared to other factors influencing the accuracy of brachytherapy

Delayed vaginal reconstruction in the fibrotic pelvis following radiation or previous reconstruction

International Nuclear Information System (INIS)

Berek, J.S.; Hacker, N.F.; Lagasse, L.D.; Smith, M.L.

1983-01-01

Vaginal reconstruction was performed in 14 patients who had developed vaginal stenosis secondary to extensive pelvic fibrosis after pelvic radiation therapy (12 patients) or prior vaginal reconstruction (2 patients). Sixteen procedures were performed using a split-thickness skin graft. All patients had satisfactory vaginal restoration, and 12 patients reported good vaginal function. No fistula developed as a result of the operative procedure, but one patient later developed a rectovaginal fistula resulting from tumor recurrence. Successful vaginal reconstruction can be achieved even years after initial therapy in patients who develop an obliterated vagina from previous radiation or surgery

Breast reconstruction following mastectomy: current status in Australia.

Science.gov (United States)

Sandelin, Kerstin; King, Elizabeth; Redman, Sally

2003-09-01

Although breast reconstruction provides some advantages for women following mastectomy, few Australian breast cancer patients currently receive reconstruction. In Australia, the routine provision of breast reconstruction will require the development of specific health service delivery models. The present paper reports an analysis of the provision of breast reconstruction in eight sites in Australia. A semi-structured telephone interview was conducted with 10 surgeons offering breast reconstruction as part of their practice, including nine breast or general surgeons and one plastic surgeon. Surgeons reported offering breast reconstruction to all women facing mastectomy; the proportion of women deciding to have breast reconstruction varied between sites with up to 50% of women having a reconstruction at some sites. Most sites offered three types of reconstruction. Two pathways emerged: either the breast surgeon performed the breast surgery in a team with the plastic surgeon who undertook the breast reconstruction or the breast surgeon provided both the breast surgery and the reconstruction. Considerable waiting times for breast reconstruction were reported in the public sector particularly for delayed reconstruction. Surgeons reported receiving training in breast reconstruction from plastic surgeons or from a breast surgery team that performed reconstructions; a number had been trained overseas. No audits of breast reconstruction were being undertaken. Breast reconstruction can be offered on a routine basis in Australia in both the private and public sectors. Women may be more readily able to access breast reconstruction when it is provided by a breast surgeon alone, but the range of reconstruction options may be more limited. If access to breast reconstruction is to be increased, there will be a need to: (i) develop effective models for the rural sector taking account of the lack of plastic surgeons; (ii) address waiting times for reconstruction surgery in the

Petz recovery versus matrix reconstruction

Science.gov (United States)

Holzäpfel, Milan; Cramer, Marcus; Datta, Nilanjana; Plenio, Martin B.

2018-04-01

The reconstruction of the state of a multipartite quantum mechanical system represents a fundamental task in quantum information science. At its most basic, it concerns a state of a bipartite quantum system whose subsystems are subjected to local operations. We compare two different methods for obtaining the original state from the state resulting from the action of these operations. The first method involves quantum operations called Petz recovery maps, acting locally on the two subsystems. The second method is called matrix (or state) reconstruction and involves local, linear maps that are not necessarily completely positive. Moreover, we compare the quantities on which the maps employed in the two methods depend. We show that any state that admits Petz recovery also admits state reconstruction. However, the latter is successful for a strictly larger set of states. We also compare these methods in the context of a finite spin chain. Here, the state of a finite spin chain is reconstructed from the reduced states of a few neighbouring spins. In this setting, state reconstruction is the same as the matrix product operator reconstruction proposed by Baumgratz et al. [Phys. Rev. Lett. 111, 020401 (2013)]. Finally, we generalize both these methods so that they employ long-range measurements instead of relying solely on short-range correlations embodied in such local reduced states. Long-range measurements enable the reconstruction of states which cannot be reconstructed from measurements of local few-body observables alone and hereby we improve existing methods for quantum state tomography of quantum many-body systems.

Barrier and operational risk analysis of hydrocarbon releases (BORA-Release)

International Nuclear Information System (INIS)

Sklet, Snorre; Vinnem, Jan Erik; Aven, Terje

2006-01-01

This paper presents results from a case study carried out on an offshore oil and gas production platform with the purpose to apply and test BORA-Release, a method for barrier and operational risk analysis of hydrocarbon releases. A description of the BORA-Release method is given in Part I of the paper. BORA-Release is applied to express the platform specific hydrocarbon release frequencies for three release scenarios for selected systems and activities on the platform. The case study demonstrated that the BORA-Release method is a useful tool for analysing the effect on the release frequency of safety barriers introduced to prevent hydrocarbon releases, and to study the effect on the barrier performance of platform specific conditions of technical, human, operational, and organisational risk influencing factors (RIFs). BORA-Release may also be used to analyse the effect on the release frequency of risk reducing measures

Breast Reconstruction After Solid Organ Transplant.

Science.gov (United States)

Koonce, Stephanie L; Giles, Brian; McLaughlin, Sarah A; Perdikis, Galen; Waldorf, James; Lemaine, Valerie; TerKonda, Sarvam

2015-09-01

Solid organ transplant patients frequently develop posttransplant malignancies including breast cancer. They may desire breast reconstruction after mastectomy, which could potentially be complicated by their transplant status, immunosuppressive regimen, and previous operations. We review our experience with patients who have undergone solid organ transplant and subsequent breast reconstruction after mastectomy After institutional review board approval, we queried our prospective breast reconstruction and solid organ transplant databases for corresponding patients. Inclusion criteria comprised breast reconstruction after solid organ transplant. A chart review was conducted of identified patients. Seventeen patients were identified: 1 pulmonary transplant, 4 cardiac transplants, 2 liver transplants, 1 pancreas transplant, 2 combined kidney/pancreas transplants, and 7 kidney transplants. Indications for mastectomy included posttransplant malignancy and prophylaxis. Median time from transplant to completion of reconstruction was 186 months (range, 11-336 months). Median age at transplant was 34.5 years (range, 21-65 years) with the median age of the patients at reconstructive surgery 51.5 years (range, 34-71 years). Median body mass index was 25.3 (range, 21.3-46.5). No significant complications were noted after reconstructive surgery. All patients were on full immunosuppression at time of reconstruction. Breast reconstruction is a viable option for transplant patients after mastectomy and should not be refused based on their transplant status. Close coordination with the transplant team and careful preoperative planning is essential for optimal outcomes.

Prosthetic breast reconstruction: indications and update

Science.gov (United States)

Quinn, Tam T.; Miller, George S.; Rostek, Marie; Cabalag, Miguel S.; Rozen, Warren M.

2016-01-01

Background Despite 82% of patients reporting psychosocial improvement following breast reconstruction, only 33% patients choose to undergo surgery. Implant reconstruction outnumbers autologous reconstruction in many centres. Methods A systematic review of the literature was undertaken. Inclusion required: (I) Meta-analyses or review articles; (II) adult patients aged 18 years or over undergoing alloplastic breast reconstruction; (III) studies including outcome measures; (IV) case series with more than 10 patients; (V) English language; and (VI) publication after 1st January, 2000. Results After full text review, analysis and data extraction was conducted for a total of 63 articles. Definitive reconstruction with an implant can be immediate or delayed. Older patients have similar or even lower complication rates to younger patients. Complications include capsular contracture, hematoma and infection. Obesity, smoking, large breasts, diabetes and higher grade tumors are associated with increased risk of wound problems and reconstructive failure. Silicone implant patients have higher capsular contracture rates but have higher physical and psychosocial function. There were no associations made between silicone implants and cancer or systemic disease. There were no differences in outcomes or complications between round and shaped implants. Textured implants have a lower risk of capsular contracture than smooth implants. Smooth implants are more likely to be displaced as well as having higher rates of infection. Immediate breast reconstruction (IBR) gives the best aesthetic outcome if radiotherapy is not required but has a higher rate of capsular contracture and implant failure. Delayed-immediate reconstruction patients can achieve similar aesthetic results to IBR whilst preserving the breast skin if radiotherapy is required. Delayed breast reconstruction (DBR) patients have fewer complications than IBR patients. Conclusions Implant reconstruction is a safe and popular

Right adrenal vein: comparison between adaptive statistical iterative reconstruction and model-based iterative reconstruction.

Science.gov (United States)

Noda, Y; Goshima, S; Nagata, S; Miyoshi, T; Kawada, H; Kawai, N; Tanahashi, Y; Matsuo, M

2018-06-01

To compare right adrenal vein (RAV) visualisation and contrast enhancement degree on adrenal venous phase images reconstructed using adaptive statistical iterative reconstruction (ASiR) and model-based iterative reconstruction (MBIR) techniques. This prospective study was approved by the institutional review board, and written informed consent was waived. Fifty-seven consecutive patients who underwent adrenal venous phase imaging were enrolled. The same raw data were reconstructed using ASiR 40% and MBIR. The expert and beginner independently reviewed computed tomography (CT) images. RAV visualisation rates, background noise, and CT attenuation of the RAV, right adrenal gland, inferior vena cava (IVC), hepatic vein, and bilateral renal veins were compared between the two reconstruction techniques. RAV visualisation rates were higher with MBIR than with ASiR (95% versus 88%, p=0.13 in expert and 93% versus 75%, p=0.002 in beginner, respectively). RAV visualisation confidence ratings with MBIR were significantly greater than with ASiR (pASiR (pASiR (p=0.0013 and 0.02). Reconstruction of adrenal venous phase images using MBIR significantly reduces background noise, leading to an improvement in the RAV visualisation compared with ASiR. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Maxillary reconstruction

Directory of Open Access Journals (Sweden)

Brown James

2007-12-01

Full Text Available This article aims to discuss the various defects that occur with maxillectomy with a full review of the literature and discussion of the advantages and disadvantages of the various techniques described. Reconstruction of the maxilla can be relatively simple for the standard low maxillectomy that does not involve the orbital floor (Class 2. In this situation the structure of the face is less damaged and the there are multiple reconstructive options for the restoration of the maxilla and dental alveolus. If the maxillectomy includes the orbit (Class 4 then problems involving the eye (enopthalmos, orbital dystopia, ectropion and diplopia are avoided which simplifies the reconstruction. Most controversy is associated with the maxillectomy that involves the orbital floor and dental alveolus (Class 3. A case is made for the use of the iliac crest with internal oblique as an ideal option but there are other methods, which may provide a similar result. A multidisciplinary approach to these patients is emphasised which should include a prosthodontist with a special expertise for these defects.

The Chernobyl I-131 Release: Model Validation and Assessment of the Countermeasure Effectiveness. Report of the Chernobyl 131I Release Working Group of EMRAS Theme 1

International Nuclear Information System (INIS)

2012-01-01

The Chernobyl 131 I Release Working Group (IWG) which was established within the framework of the EMRAS Programme continues some of the more traditional work of previous international programmes that were aimed at increasing confidence in methods and models for the assessment of radiation exposure related to the environmental releases. There is still very little information regarding the quantitative relationship between radiation dose to the thyroid from Chernobyl and the risk of thyroid cancer. The uncertainty combined with individual estimates of radiation dose constitutes a crucial point in establishing this relationship, since, any release of radioiodine into environment creates wide range of uncertainty for internal dose assessments. The 131 I scenarios provide an excellent opportunity to compare a number of modelling approaches to a single assessment problem, in a dose reconstruction context. Nine experts in environmental modelling participated in the Plavsk Scenario dealing with areas of assessment modelling for which the capabilities are not yet well established. One could observes the remarkably improvement in models performance comparing with previous radioiodine scenarios. Predictions of the various models were within a factor of three of the observations, discrepancies between the estimates of average doses to thyroid produced by most participant not exceeded a factor of ten. The process of testing independent model calculations against independent data set also provided useful information to the originators of the test data.

Graft infections after surgical aortic reconstructions

OpenAIRE

Berger, P.

2015-01-01

Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open surgical reconstructions as first line of treatment for aorto-iliac diseases. Nowadays, open reconstructions are primarily reserved for patients unsuitable for endovascular reconstructions or for redo ...

REGEN: Ancestral Genome Reconstruction for Bacteria

OpenAIRE

Yang, Kuan; Heath, Lenwood S.; Setubal, João C.

2012-01-01

Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deleti...

Craniofacial Reconstruction Evaluation by Geodesic Network

OpenAIRE

Zhao, Junli; Liu, Cuiting; Wu, Zhongke; Duan, Fuqing; Wang, Kang; Jia, Taorui; Liu, Quansheng

2014-01-01

Craniofacial reconstruction is to estimate an individual’s face model from its skull. It has a widespread application in forensic medicine, archeology, medical cosmetic surgery, and so forth. However, little attention is paid to the evaluation of craniofacial reconstruction. This paper proposes an objective method to evaluate globally and locally the reconstructed craniofacial faces based on the geodesic network. Firstly, the geodesic networks of the reconstructed craniofacial face and the or...

Overview of image reconstruction

International Nuclear Information System (INIS)

Marr, R.B.

1980-04-01

Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on R/sup n/ is estimated from empirical data pertaining to its integrals, ∫f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, electron microscopy, acoustical imaging, geophysical tomography, nondestructive testing, and NMR zeugmatography. Then the various reconstruction algorithms are discussed in five classes: summation, or simple back-projection; convolution, or filtered back-projection; Fourier and other functional transforms; orthogonal function series expansion; and iterative methods. Certain more technical mathematical aspects of image reconstruction are considered from the standpoint of uniqueness, consistency, and stability of solution. The paper concludes by presenting certain open problems. 73 references

Virtual 3-D Facial Reconstruction

Directory of Open Access Journals (Sweden)

Martin Paul Evison

2000-06-01

Full Text Available Facial reconstructions in archaeology allow empathy with people who lived in the past and enjoy considerable popularity with the public. It is a common misconception that facial reconstruction will produce an exact likeness; a resemblance is the best that can be hoped for. Research at Sheffield University is aimed at the development of a computer system for facial reconstruction that will be accurate, rapid, repeatable, accessible and flexible. This research is described and prototypical 3-D facial reconstructions are presented. Interpolation models simulating obesity, ageing and ethnic affiliation are also described. Some strengths and weaknesses in the models, and their potential for application in archaeology are discussed.

Image quality of iterative reconstruction in cranial CT imaging: comparison of model-based iterative reconstruction (MBIR) and adaptive statistical iterative reconstruction (ASiR).

Science.gov (United States)

Notohamiprodjo, S; Deak, Z; Meurer, F; Maertz, F; Mueck, F G; Geyer, L L; Wirth, S

2015-01-01

The purpose of this study was to compare cranial CT (CCT) image quality (IQ) of the MBIR algorithm with standard iterative reconstruction (ASiR). In this institutional review board (IRB)-approved study, raw data sets of 100 unenhanced CCT examinations (120 kV, 50-260 mAs, 20 mm collimation, 0.984 pitch) were reconstructed with both ASiR and MBIR. Signal-to-noise (SNR) and contrast-to-noise (CNR) were calculated from attenuation values measured in caudate nucleus, frontal white matter, anterior ventricle horn, fourth ventricle, and pons. Two radiologists, who were blinded to the reconstruction algorithms, evaluated anonymized multiplanar reformations of 2.5 mm with respect to depiction of different parenchymal structures and impact of artefacts on IQ with a five-point scale (0: unacceptable, 1: less than average, 2: average, 3: above average, 4: excellent). MBIR decreased artefacts more effectively than ASiR (p ASiR was 2 (p ASiR (p ASiR. As CCT is an examination that is frequently required, the use of MBIR may allow for substantial reduction of radiation exposure caused by medical diagnostics. • Model-Based iterative reconstruction (MBIR) effectively decreased artefacts in cranial CT. • MBIR reconstructed images were rated with significantly higher scores for image quality. • Model-Based iterative reconstruction may allow reduced-dose diagnostic examination protocols.

REGEN: Ancestral Genome Reconstruction for Bacteria.

Science.gov (United States)

Yang, Kuan; Heath, Lenwood S; Setubal, João C

2012-07-18

Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deletion and replicon fission and fusion. The reconstruction can be performed by either a maximum parsimony or a maximum likelihood method. Gene content reconstruction is based on the concept of neighboring gene pairs. REGEN was designed to be used with any set of genomes that are sufficiently related, which will usually be the case for bacteria within the same taxonomic order. We evaluated REGEN using simulated genomes and genomes in the Rhizobiales order.

REGEN: Ancestral Genome Reconstruction for Bacteria

Directory of Open Access Journals (Sweden)

João C. Setubal

2012-07-01

Full Text Available Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deletion and replicon fission and fusion. The reconstruction can be performed by either a maximum parsimony or a maximum likelihood method. Gene content reconstruction is based on the concept of neighboring gene pairs. REGEN was designed to be used with any set of genomes that are sufficiently related, which will usually be the case for bacteria within the same taxonomic order. We evaluated REGEN using simulated genomes and genomes in the Rhizobiales order.

Computer Based Road Accident Reconstruction Experiences

Directory of Open Access Journals (Sweden)

Milan Batista

2005-03-01

Full Text Available Since road accident analyses and reconstructions are increasinglybased on specific computer software for simulationof vehicle d1iving dynamics and collision dynamics, and forsimulation of a set of trial runs from which the model that bestdescribes a real event can be selected, the paper presents anoverview of some computer software and methods available toaccident reconstruction experts. Besides being time-saving,when properly used such computer software can provide moreauthentic and more trustworthy accident reconstruction, thereforepractical experiences while using computer software toolsfor road accident reconstruction obtained in the TransportSafety Laboratory at the Faculty for Maritime Studies andTransport of the University of Ljubljana are presented and discussed.This paper addresses also software technology for extractingmaximum information from the accident photo-documentationto support accident reconstruction based on the simulationsoftware, as well as the field work of reconstruction expertsor police on the road accident scene defined by this technology.

Data-parallel tomographic reconstruction : A comparison of filtered backprojection and direct Fourier reconstruction

NARCIS (Netherlands)

Roerdink, J.B.T.M.; Westenberg, M.A

1998-01-01

We consider the parallelization of two standard 2D reconstruction algorithms, filtered backprojection and direct Fourier reconstruction, using the data-parallel programming style. The algorithms are implemented on a Connection Machine CM-5 with 16 processors and a peak performance of 2 Gflop/s.

Vertex Reconstruction in ATLAS Run II

CERN Document Server

Zhang, Matt; The ATLAS collaboration

2016-01-01

Vertex reconstruction is the process of taking reconstructed tracks and using them to determine the locations of proton collisions. In this poster we present the performance of our current vertex reconstruction algorithm, and look at investigations into potential improvements from a new seed finding method.

Photoacoustic image reconstruction via deep learning

Science.gov (United States)

Antholzer, Stephan; Haltmeier, Markus; Nuster, Robert; Schwab, Johannes

2018-02-01

Applying standard algorithms to sparse data problems in photoacoustic tomography (PAT) yields low-quality images containing severe under-sampling artifacts. To some extent, these artifacts can be reduced by iterative image reconstruction algorithms which allow to include prior knowledge such as smoothness, total variation (TV) or sparsity constraints. These algorithms tend to be time consuming as the forward and adjoint problems have to be solved repeatedly. Further, iterative algorithms have additional drawbacks. For example, the reconstruction quality strongly depends on a-priori model assumptions about the objects to be recovered, which are often not strictly satisfied in practical applications. To overcome these issues, in this paper, we develop direct and efficient reconstruction algorithms based on deep learning. As opposed to iterative algorithms, we apply a convolutional neural network, whose parameters are trained before the reconstruction process based on a set of training data. For actual image reconstruction, a single evaluation of the trained network yields the desired result. Our presented numerical results (using two different network architectures) demonstrate that the proposed deep learning approach reconstructs images with a quality comparable to state of the art iterative reconstruction methods.

Beard reconstruction: A surgical algorithm.

Science.gov (United States)

Ninkovic, M; Heidekrueger, P I; Ehrl, D; von Spiegel, F; Broer, P N

2016-06-01

Facial defects with loss of hair-bearing regions can be caused by trauma, infection, tumor excision, or burn injury. The presented analysis evaluates a series of different surgical approaches with a focus on male beard reconstruction, emphasizing the role of tissue expansion of regional and free flaps. Locoregional and free flap reconstructions were performed in 11 male patients with 14 facial defects affecting the hair-bearing bucco-mandibular or perioral region. In order to minimize donor-site morbidity and obtain large amounts of thin, pliable, hair-bearing tissue, pre-expansion was performed in five of 14 patients. Eight of 14 patients were treated with locoregional flap reconstructions and six with free flap reconstructions. Algorithms regarding pre- and intraoperative decision making are discussed and long-term (mean follow-up 1.5 years) results analyzed. Major complications, including tissue expander infection with the need for removal or exchange, partial or full flap loss, occurred in 0% (0/8) of patients with locoregional flaps and in 17% (1/6) of patients undergoing free flap reconstructions. Secondary refinement surgery was performed in 25% (2/8) of locoregional flaps and in 67% (4/6) of free flaps. Both locoregional and distant tissue transfers play a role in beard reconstruction, while pre-expansion remains an invaluable tool. Paying attention to the presented principles and considering the significance of aesthetic facial subunits, range of motion, aesthetics, and patient satisfaction were improved long term in all our patients while minimizing donor-site morbidity. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Forensic Facial Reconstruction: The Final Frontier.

Science.gov (United States)

Gupta, Sonia; Gupta, Vineeta; Vij, Hitesh; Vij, Ruchieka; Tyagi, Nutan

2015-09-01

Forensic facial reconstruction can be used to identify unknown human remains when other techniques fail. Through this article, we attempt to review the different methods of facial reconstruction reported in literature. There are several techniques of doing facial reconstruction, which vary from two dimensional drawings to three dimensional clay models. With the advancement in 3D technology, a rapid, efficient and cost effective computerized 3D forensic facial reconstruction method has been developed which has brought down the degree of error previously encountered. There are several methods of manual facial reconstruction but the combination Manchester method has been reported to be the best and most accurate method for the positive recognition of an individual. Recognition allows the involved government agencies to make a list of suspected victims'. This list can then be narrowed down and a positive identification may be given by the more conventional method of forensic medicine. Facial reconstruction allows visual identification by the individual's family and associates to become easy and more definite.

Alternative reconstruction after pancreaticoduodenectomy

Directory of Open Access Journals (Sweden)

Cooperman Avram M

2008-01-01

Full Text Available Abstract Background Pancreaticoduodenectomy is the procedure of choice for tumors of the head of the pancreas and periampulla. Despite advances in surgical technique and postoperative care, the procedure continues to carry a high morbidity rate. One of the most common morbidities is delayed gastric emptying with rates of 15%–40%. Following two prolonged cases of delayed gastric emptying, we altered our reconstruction to avoid this complication altogether. Subsequently, our patients underwent a classic pancreaticoduodenectomy with an undivided Roux-en-Y technique for reconstruction. Methods We reviewed the charts of our last 13 Whipple procedures evaluating them for complications, specifically delayed gastric emptying. We compared the outcomes of those patients to a control group of 15 patients who underwent the Whipple procedure with standard reconstruction. Results No instances of delayed gastric emptying occurred in patients who underwent an undivided Roux-en-Y technique for reconstruction. There was 1 wound infection (8%, 1 instance of pneumonia (8%, and 1 instance of bleeding from the gastrojejunal staple line (8%. There was no operative mortality. Conclusion Use of the undivided Roux-en-Y technique for reconstruction following the Whipple procedure may decrease the incidence of delayed gastric emptying. In addition, it has the added benefit of eliminating bile reflux gastritis. Future randomized control trials are recommended to further evaluate the efficacy of the procedure.

Study of DNA reconstruction enzymes

Energy Technology Data Exchange (ETDEWEB)

Sekiguchi, M [Kyushu Univ., Fukuoka (Japan). Faculty of Science

1976-12-01

Description was made of the characteristics and mechanism of 3 reconstructive enzymes which received from M. luteus or E. coli or T4, and of which natures were clarified as reconstructive enzymes of DNA irradiated with ultraviolet rays. As characteristics, the site of breaking, reaction, molecular weight, electric charge in the neutrality and a specific adhesion to DNA irradiated with ultraviolet rays were mentioned. As to mutant of ultraviolet ray sensitivity, hereditary control mechanism of removal and reconstruction by endo-nuclease activation was described, and suggestion was referred to removal and reconstruction of cells of xedoderma pigmentosum which is a hereditary disease of human. Description was also made as to the mechanism of exonuclease activation which separates dimer selectively from irradiated DNA.

Reconstructing random media

International Nuclear Information System (INIS)

Yeong, C.L.; Torquato, S.

1998-01-01

We formulate a procedure to reconstruct the structure of general random heterogeneous media from limited morphological information by extending the methodology of Rintoul and Torquato [J. Colloid Interface Sci. 186, 467 (1997)] developed for dispersions. The procedure has the advantages that it is simple to implement and generally applicable to multidimensional, multiphase, and anisotropic structures. Furthermore, an extremely useful feature is that it can incorporate any type and number of correlation functions in order to provide as much morphological information as is necessary for accurate reconstruction. We consider a variety of one- and two-dimensional reconstructions, including periodic and random arrays of rods, various distribution of disks, Debye random media, and a Fontainebleau sandstone sample. We also use our algorithm to construct heterogeneous media from specified hypothetical correlation functions, including an exponentially damped, oscillating function as well as physically unrealizable ones. copyright 1998 The American Physical Society

Industrial dynamic tomographic reconstruction

International Nuclear Information System (INIS)

Oliveira, Eric Ferreira de

2016-01-01

The state of the art methods applied to industrial processes is currently based on the principles of classical tomographic reconstructions developed for tomographic patterns of static distributions, or is limited to cases of low variability of the density distribution function of the tomographed object. Noise and motion artifacts are the main problems caused by a mismatch in the data from views acquired in different instants. All of these add to the known fact that using a limited amount of data can result in the presence of noise, artifacts and some inconsistencies with the distribution under study. One of the objectives of the present work is to discuss the difficulties that arise from implementing reconstruction algorithms in dynamic tomography that were originally developed for static distributions. Another objective is to propose solutions that aim at reducing a temporal type of information loss caused by employing regular acquisition systems to dynamic processes. With respect to dynamic image reconstruction it was conducted a comparison between different static reconstruction methods, like MART and FBP, when used for dynamic scenarios. This comparison was based on a MCNPx simulation as well as an analytical setup of an aluminum cylinder that moves along the section of a riser during the process of acquisition, and also based on cross section images from CFD techniques. As for the adaptation of current tomographic acquisition systems for dynamic processes, this work established a sequence of tomographic views in a just-in-time fashion for visualization purposes, a form of visually disposing density information as soon as it becomes amenable to image reconstruction. A third contribution was to take advantage of the triple color channel necessary to display colored images in most displays, so that, by appropriately scaling the acquired values of each view in the linear system of the reconstruction, it was possible to imprint a temporal trace into the regularly

[Pelvic reconstructions after bone tumor resection].

Science.gov (United States)

Anract, Philippe; Biau, David; Babinet, Antoine; Tomeno, Bernard

2014-02-01

The three more frequent primitive malignant bone tumour which concerned the iliac bone are chondrosarcoma, following Ewing sarcoma and osteosarcoma. Wide resection remains the most important part of the treatment associated with chemotherapy for osteosarcoma and the Ewing sarcoma. Iliac wing resections and obdurate ring don't required reconstruction. However, acetabular resections and iliac wing resection with disruption of the pelvic ring required reconstruction to provide acceptable functional result. Acetabular reconstruction remains high technical demanding challenge. After isolated acetabular resection or associated to obdurate ring, our usual method of reconstruction is homolateral proximal femoral autograft and total hip prosthesis but it is possible to also used : saddle prosthesis, Mac Minn prosthesis with auto or allograft, modular prosthesis or custom made prosthesis, massive allograft with or without prosthesis and femoro-ilac arthrodesis. After resection of the iliac wing plus acetabulum, reconstruction can be performed by femoro-obturatrice and femora-sacral arthrodesis, homolateral proximal femoral autograft and prosthesis, femoral medialisation, massive allograft and massive allograft. Carcinological results are lesser than resection for distal limb tumor, local recurrence rate range 17 to 45%. Functional results after Iliac wing and obdurate ring are good. However, acetabular reconstruction provide uncertain functional results. The lesser results arrive after hemipelvic or acetabular and iliac wing resection-reconstruction, especially when gluteus muscles were also resected. The most favourable results arrive after isolated acetabular or acetabular plus obturateur ring resection-reconstruction.

lpNet: a linear programming approach to reconstruct signal transduction networks.

Science.gov (United States)

Matos, Marta R A; Knapp, Bettina; Kaderali, Lars

2015-10-01

With the widespread availability of high-throughput experimental technologies it has become possible to study hundreds to thousands of cellular factors simultaneously, such as coding- or non-coding mRNA or protein concentrations. Still, extracting information about the underlying regulatory or signaling interactions from these data remains a difficult challenge. We present a flexible approach towards network inference based on linear programming. Our method reconstructs the interactions of factors from a combination of perturbation/non-perturbation and steady-state/time-series data. We show both on simulated and real data that our methods are able to reconstruct the underlying networks fast and efficiently, thus shedding new light on biological processes and, in particular, into disease's mechanisms of action. We have implemented the approach as an R package available through bioconductor. This R package is freely available under the Gnu Public License (GPL-3) from bioconductor.org (http://bioconductor.org/packages/release/bioc/html/lpNet.html) and is compatible with most operating systems (Windows, Linux, Mac OS) and hardware architectures. bettina.knapp@helmholtz-muenchen.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Optimizing Functional Outcomes in Mandibular Condyle Reconstruction With the Free Fibula Flap Using Computer-Aided Design and Manufacturing Technology.

Science.gov (United States)

Lee, Z-Hye; Avraham, Tomer; Monaco, Casian; Patel, Ashish A; Hirsch, David L; Levine, Jamie P

2018-05-01

Mandibular defects involving the condyle represent a complex reconstructive challenge for restoring proper function of the temporomandibular joint (TMJ) because it requires precise bone graft alignment for full restoration of joint function. The use of computer-aided design and manufacturing (CAD/CAM) technology can aid in accurate reconstruction of mandibular condyle defects with a vascularized free fibula flap without the need for additional adjuncts. The purpose of this study was to analyze clinical and functional outcomes after reconstruction of mandibular condyle defects using only a free fibula graft with the help of virtual surgery techniques. A retrospective review was performed to identify all patients who underwent mandibular reconstruction with only a free fibula flap without any TMJ adjuncts after a total condylectomy. Three-dimensional modeling software was used to plan and execute reconstruction for all patients. From 2009 through 2014, 14 patients underwent reconstruction of mandibular defects involving the condyle with the aid of virtual surgery technology. The average age was 38.7 years (range, 11 to 77 yr). The average follow-up period was 2.6 years (range, 0.8 to 4.2 yr). Flap survival was 100% (N = 14). All patients reported improved facial symmetry, adequate jaw opening, and normal dental occlusion. In addition, they achieved good functional outcomes, including normal intelligible speech and the tolerance of a regular diet with solid foods. Maximal interincisal opening range for all patients was 25 to 38 mm with no lateral deviation or subjective joint pain. No patient had progressive joint hypomobility or condylar migration. One patient had ankylosis, which required release. TMJ reconstruction poses considerable challenges in bone graft alignment for full restoration of joint function. The use of CAD/CAM technology can aid in accurate reconstruction of mandibular condyle defects with a vascularized free fibula flap through precise

Retrospective reconstruction of Iodine-131 distribution through the analysis of Iodine-129

Science.gov (United States)

Matsuzaki, Hiroyuki; Muramatsu, Yasuyuki; Ohno, Takeshi; Mao, Wei

2017-09-01

Iodine-131 distribution released from the Fukushima Dai-ichi Nuclear Power Plant accident was reconstructed through the iodine-129 measurements. From nearly 1,000 surface soil samples iodine was extracted by the pyro hydrolysis method. Extracted iodine was then mixed with carrier, purified and finally collected as silver iodide. Silver iodide sample was pressed into the cathode holder and set at the ion source of the MALT facility, The University of Tokyo. The isotopic ratio 129I/127I was measured by means of Accelerator Mass Spectrometry. From 129I data obtained, 131I deposition map was constructed. There observed various fine structures in the map which could not estimated neither by the simulation nor 137Cs distribution.

Maxillary reconstruction: Current concepts and controversies

Directory of Open Access Journals (Sweden)

Subramania Iyer

2014-01-01

Full Text Available Maxillary reconstruction is still an evolving art when compared to the reconstruction of the mandible. The defects of maxilla apart from affecting the functions of the speech, swallowing and mastication also cause cosmetic disfigurement. Rehabilitation of the form and function in patients with maxillary defects is either by using an obturator prosthesis or by a surgical reconstruction. Literature is abundant with a variety of reconstructive methods. The classification systems are also varied, with no universal acceptance of any one of them. The oncologic safety of these procedures is still debated, and conclusive evidence in this regard has not emerged yet. Management of the orbit is also not yet addressed properly. Tissue engineering, that has been hyped to be one of the possible solutions for this vexing reconstructive problem, has not come out with reliable and reproducible results so far. This review article discusses the rationale and oncological safety of the reconstructing the maxillary defects, critically analyzes the classification systems, offers the different reconstructive methods and touches upon the controversies in this subject. The management of the retained and exenterated orbit associated with maxillectomy is reviewed. The surgical morbidity, complications and the recent advances in this field are also looked into. An algorithm, based on our experience, is presented.

Maxillary reconstruction: Current concepts and controversies

Science.gov (United States)

Iyer, Subramania; Thankappan, Krishnakumar

2014-01-01

Maxillary reconstruction is still an evolving art when compared to the reconstruction of the mandible. The defects of maxilla apart from affecting the functions of the speech, swallowing and mastication also cause cosmetic disfigurement. Rehabilitation of the form and function in patients with maxillary defects is either by using an obturator prosthesis or by a surgical reconstruction. Literature is abundant with a variety of reconstructive methods. The classification systems are also varied, with no universal acceptance of any one of them. The oncologic safety of these procedures is still debated, and conclusive evidence in this regard has not emerged yet. Management of the orbit is also not yet addressed properly. Tissue engineering, that has been hyped to be one of the possible solutions for this vexing reconstructive problem, has not come out with reliable and reproducible results so far. This review article discusses the rationale and oncological safety of the reconstructing the maxillary defects, critically analyzes the classification systems, offers the different reconstructive methods and touches upon the controversies in this subject. The management of the retained and exenterated orbit associated with maxillectomy is reviewed. The surgical morbidity, complications and the recent advances in this field are also looked into. An algorithm, based on our experience, is presented. PMID:24987199

Iterative reconstruction reduces abdominal CT dose

International Nuclear Information System (INIS)

Martinsen, Anne Catrine Trægde; Sæther, Hilde Kjernlie; Hol, Per Kristian; Olsen, Dag Rune; Skaane, Per

2012-01-01

Objective: In medical imaging, lowering radiation dose from computed tomography scanning, without reducing diagnostic performance is a desired achievement. Iterative image reconstruction may be one tool to achieve dose reduction. This study reports the diagnostic performance using a blending of 50% statistical iterative reconstruction (ASIR) and filtered back projection reconstruction (FBP) compared to standard FBP image reconstruction at different dose levels for liver phantom examinations. Methods: An anthropomorphic liver phantom was scanned at 250, 185, 155, 140, 120 and 100 mA s, on a 64-slice GE Lightspeed VCT scanner. All scans were reconstructed with ASIR and FBP. Four readers evaluated independently on a 5-point scale 21 images, each containing 32 test sectors. In total 672 areas were assessed. ROC analysis was used to evaluate the differences. Results: There was a difference in AUC between the 250 mA s FBP images and the 120 and 100 mA s FBP images. ASIR reconstruction gave a significantly higher diagnostic performance compared to standard reconstruction at 100 mA s. Conclusion: A blending of 50–90% ASIR and FBP may improve image quality of low dose CT examinations of the liver, and thus give a potential for reducing radiation dose.

Results of isolated lateral retinacular reconstruction for iatrogenic medial patellar instability.

Science.gov (United States)

Sanchis-Alfonso, Vicente; Montesinos-Berry, Erik; Monllau, Joan Carles; Merchant, Alan C

2015-03-01

The aim of this study was to assess the outcomes of an isolated lateral retinaculum reconstruction for iatrogenic medial patellar instability (IMPI) in patients with continued pain after failed lateral retinacular release (LRR), including associated psychometric analysis. Pain was assessed using the visual analog scale (VAS) and disability was determined with the Lysholm scale. Psychological variables such as anxiety, depression, catastrophizing, and fear-of-movement beliefs were studied by using self-administered psychometric questionnaires. All 17 patients (13 women and 4 men) in this retrospective study had undergone LRR previously for anterior knee pain or lateral patellar instability. Four patients had undergone LRR plus proximal (Insall) realignment, and one had undergone LRR plus a medial tibial tubercle transfer. After their procedures, all had disabling symptoms. All patients underwent reconstructive surgery for IMPI. At a minimum follow-up of 2 years (range, 2 to 8 years), the mean preoperative VAS score was 7.6 (range, 5 to 9) and improved to 1.9 (range, 0 to 8) at the time of final follow-up (P surgery, 4 patients (24%) had the clinical criteria for depression, 10 (59%) had anxiety, 7 (41%) had "catastrophizing" ideas concerning pain, and all (100%) had kinesiophobia (fear of movement). After surgery, none of the patients had depression or anxiety, none had catastrophizing ideation, and only 53% had kinesiophobia. Reconstruction of the deep transverse layer of the lateral retinaculum (LR) using a central strip of the iliotibial band for IMPI in patients with continued pain after failed LRR can successfully treat these severely disabled patients. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Image reconstruction by domain-transform manifold learning

Science.gov (United States)

Zhu, Bo; Liu, Jeremiah Z.; Cauley, Stephen F.; Rosen, Bruce R.; Rosen, Matthew S.

2018-03-01

Image reconstruction is essential for imaging applications across the physical and life sciences, including optical and radar systems, magnetic resonance imaging, X-ray computed tomography, positron emission tomography, ultrasound imaging and radio astronomy. During image acquisition, the sensor encodes an intermediate representation of an object in the sensor domain, which is subsequently reconstructed into an image by an inversion of the encoding function. Image reconstruction is challenging because analytic knowledge of the exact inverse transform may not exist a priori, especially in the presence of sensor non-idealities and noise. Thus, the standard reconstruction approach involves approximating the inverse function with multiple ad hoc stages in a signal processing chain, the composition of which depends on the details of each acquisition strategy, and often requires expert parameter tuning to optimize reconstruction performance. Here we present a unified framework for image reconstruction—automated transform by manifold approximation (AUTOMAP)—which recasts image reconstruction as a data-driven supervised learning task that allows a mapping between the sensor and the image domain to emerge from an appropriate corpus of training data. We implement AUTOMAP with a deep neural network and exhibit its flexibility in learning reconstruction transforms for various magnetic resonance imaging acquisition strategies, using the same network architecture and hyperparameters. We further demonstrate that manifold learning during training results in sparse representations of domain transforms along low-dimensional data manifolds, and observe superior immunity to noise and a reduction in reconstruction artefacts compared with conventional handcrafted reconstruction methods. In addition to improving the reconstruction performance of existing acquisition methodologies, we anticipate that AUTOMAP and other learned reconstruction approaches will accelerate the development

A Reduction of the Graph Reconstruction Conjecture

Directory of Open Access Journals (Sweden)

Monikandan S.

2014-08-01

Full Text Available A graph is said to be reconstructible if it is determined up to isomor- phism from the collection of all its one-vertex deleted unlabeled subgraphs. Reconstruction Conjecture (RC asserts that all graphs on at least three vertices are reconstructible. In this paper, we prove that interval-regular graphs and some new classes of graphs are reconstructible and show that RC is true if and only if all non-geodetic and non-interval-regular blocks G with diam(G = 2 or diam(Ḡ = diam(G = 3 are reconstructible

Reconstructing Topological Graphs and Continua

OpenAIRE

Gartside, Paul; Pitz, Max F.; Suabedissen, Rolf

2015-01-01

The deck of a topological space $X$ is the set $\\mathcal{D}(X)=\\{[X \\setminus \\{x\\}] \\colon x \\in X\\}$, where $[Z]$ denotes the homeomorphism class of $Z$. A space $X$ is topologically reconstructible if whenever $\\mathcal{D}(X)=\\mathcal{D}(Y)$ then $X$ is homeomorphic to $Y$. It is shown that all metrizable compact connected spaces are reconstructible. It follows that all finite graphs, when viewed as a 1-dimensional cell-complex, are reconstructible in the topological sense, and more genera...

Delayed breast implant reconstruction

DEFF Research Database (Denmark)

Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

2012-01-01

We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

Accuracy of fibula reconstruction using patient-specific CAD/CAM reconstruction plates and dental implants : A new modality for functional reconstruction of mandibular defects

NARCIS (Netherlands)

Schepers, Rutger H.; Raghoebar, Gerry M.; Vissink, Arjan; Stenekes, Martin W.; Kraeima, Joep; Roodenburg, Jan L.; Reintsema, Harry; Witjes, Max J.

Background: The purpose of this study was to analyze the accuracy of mandibular reconstruction using patient-specific computer-aided designed and computer-aided manufactured (CAD/CAM) reconstruction plates as a guide to place fibula grafts and dental implants in a one-stage procedure using

Alpha image reconstruction (AIR): A new iterative CT image reconstruction approach using voxel-wise alpha blending

International Nuclear Information System (INIS)

Hofmann, Christian; Sawall, Stefan; Knaup, Michael; Kachelrieß, Marc

2014-01-01

Purpose: Iterative image reconstruction gains more and more interest in clinical routine, as it promises to reduce image noise (and thereby patient dose), to reduce artifacts, or to improve spatial resolution. Among vendors and researchers, however, there is no consensus of how to best achieve these aims. The general approach is to incorporatea priori knowledge into iterative image reconstruction, for example, by adding additional constraints to the cost function, which penalize variations between neighboring voxels. However, this approach to regularization in general poses a resolution noise trade-off because the stronger the regularization, and thus the noise reduction, the stronger the loss of spatial resolution and thus loss of anatomical detail. The authors propose a method which tries to improve this trade-off. The proposed reconstruction algorithm is called alpha image reconstruction (AIR). One starts with generating basis images, which emphasize certain desired image properties, like high resolution or low noise. The AIR algorithm reconstructs voxel-specific weighting coefficients that are applied to combine the basis images. By combining the desired properties of each basis image, one can generate an image with lower noise and maintained high contrast resolution thus improving the resolution noise trade-off. Methods: All simulations and reconstructions are performed in native fan-beam geometry. A water phantom with resolution bar patterns and low contrast disks is simulated. A filtered backprojection (FBP) reconstruction with a Ram-Lak kernel is used as a reference reconstruction. The results of AIR are compared against the FBP results and against a penalized weighted least squares reconstruction which uses total variation as regularization. The simulations are based on the geometry of the Siemens Somatom Definition Flash scanner. To quantitatively assess image quality, the authors analyze line profiles through resolution patterns to define a contrast

[Reconstructive surgery of cranio-orbital injuries].

Science.gov (United States)

Eolchiian, S A; Potapov, A A; Serova, N K; Kataev, M G; Sergeeva, L A; Zakharova, N E; Van Damm, P

2011-01-01

The aim of study was to optimize evaluation and surgery of cranioorbital injuries in different periods after trauma. Material and methods. We analyzed 374 patients with cranioorbital injuries treated in Burdenko Neurosurgery Institute in different periods after trauma from January 1998 till April 2010. 288 (77%) underwent skull and facial skeleton reconstructive surgery within 24 hours - 7 years after trauma. Clinical and CT examination data were used for preoperative planning and assessment of surgery results. Stereolithographic models (STLM) were applied for preoperative planning in 89 cases. The follow-up period ranged from 4 months up to 10 years. Results. In 254 (88%) of 288 patients reconstruction of anterior skull base, upper and/or midface with restoration of different parts of orbit was performed. Anterior skull base CSF leaks repair, calvarial vault reconstruction, maxillar and mandibular osteosynthesis were done in 34 (12%) cases. 242 (84%) of 288 patients underwent one reconstructive operation, while 46 (16%)--two and more (totally 105 operations). The patients with extended frontoorbital and midface fractures commonly needed more than one operation--in 27 (62.8%) cases. Different plastic materials were used for reconstruction in 233 (80.9%) patients, of those in 147 (51%) cases split calvarial bone grafts were preferred. Good functional and cosmetic results were achieved in 261 (90.6%) of 288 patients while acceptable were observed in 27 (9.4%). Conclusion. Active single-stage surgical management for repair of combined cranioorbital injury in acute period with primary reconstruction optimizes functional and cosmetic outcomes and prevents the problems of delayed or secondary reconstruction. Severe extended anterior skull base, upper and midface injuries when intracranial surgery is needed produced the most challenging difficulties for adequate reconstruction. Randomized trial is required to define the extent and optimal timing of reconstructive surgery

Compressed Sensing, Pseudodictionary-Based, Superresolution Reconstruction

Directory of Open Access Journals (Sweden)

Chun-mei Li

2016-01-01

Full Text Available The spatial resolution of digital images is the critical factor that affects photogrammetry precision. Single-frame, superresolution, image reconstruction is a typical underdetermined, inverse problem. To solve this type of problem, a compressive, sensing, pseudodictionary-based, superresolution reconstruction method is proposed in this study. The proposed method achieves pseudodictionary learning with an available low-resolution image and uses the K-SVD algorithm, which is based on the sparse characteristics of the digital image. Then, the sparse representation coefficient of the low-resolution image is obtained by solving the norm of l0 minimization problem, and the sparse coefficient and high-resolution pseudodictionary are used to reconstruct image tiles with high resolution. Finally, single-frame-image superresolution reconstruction is achieved. The proposed method is applied to photogrammetric images, and the experimental results indicate that the proposed method effectively increase image resolution, increase image information content, and achieve superresolution reconstruction. The reconstructed results are better than those obtained from traditional interpolation methods in aspect of visual effects and quantitative indicators.

Distributed MRI reconstruction using Gadgetron-based cloud computing.

Science.gov (United States)

Xue, Hui; Inati, Souheil; Sørensen, Thomas Sangild; Kellman, Peter; Hansen, Michael S

2015-03-01

To expand the open source Gadgetron reconstruction framework to support distributed computing and to demonstrate that a multinode version of the Gadgetron can be used to provide nonlinear reconstruction with clinically acceptable latency. The Gadgetron framework was extended with new software components that enable an arbitrary number of Gadgetron instances to collaborate on a reconstruction task. This cloud-enabled version of the Gadgetron was deployed on three different distributed computing platforms ranging from a heterogeneous collection of commodity computers to the commercial Amazon Elastic Compute Cloud. The Gadgetron cloud was used to provide nonlinear, compressed sensing reconstruction on a clinical scanner with low reconstruction latency (eg, cardiac and neuroimaging applications). The proposed setup was able to handle acquisition and 11 -SPIRiT reconstruction of nine high temporal resolution real-time, cardiac short axis cine acquisitions, covering the ventricles for functional evaluation, in under 1 min. A three-dimensional high-resolution brain acquisition with 1 mm(3) isotropic pixel size was acquired and reconstructed with nonlinear reconstruction in less than 5 min. A distributed computing enabled Gadgetron provides a scalable way to improve reconstruction performance using commodity cluster computing. Nonlinear, compressed sensing reconstruction can be deployed clinically with low image reconstruction latency. © 2014 Wiley Periodicals, Inc.

Surface Reconstruction from Parallel Curves with Application to Parietal Bone Fracture Reconstruction.

Directory of Open Access Journals (Sweden)

Abdul Majeed

Full Text Available Maxillofacial trauma are common, secondary to road traffic accident, sports injury, falls and require sophisticated radiological imaging to precisely diagnose. A direct surgical reconstruction is complex and require clinical expertise. Bio-modelling helps in reconstructing surface model from 2D contours. In this manuscript we have constructed the 3D surface using 2D Computerized Tomography (CT scan contours. The fracture part of the cranial vault are reconstructed using GC1 rational cubic Ball curve with three free parameters, later the 2D contours are flipped into 3D with equidistant z component. The constructed surface is represented by contours blending interpolant. At the end of this manuscript a case report of parietal bone fracture is also illustrated by employing this method with a Graphical User Interface (GUI illustration.

Orbital Reconstruction: Patient-Specific Orbital Floor Reconstruction Using a Mirroring Technique and a Customized Titanium Mesh.

Science.gov (United States)

Tarsitano, Achille; Badiali, Giovanni; Pizzigallo, Angelo; Marchetti, Claudio

2016-10-01

Enophthalmos is a severe complication of primary reconstruction of orbital floor fractures. The goal of secondary reconstruction procedures is to restore symmetrical globe positions to recover function and aesthetics. The authors propose a new method of orbital floor reconstruction using a mirroring technique and a customized titanium mesh, printed using a direct metal laser-sintering method. This reconstructive protocol involves 4 steps: mirroring of the healthy orbit at the affected site, virtual design of a patient-specific orbital floor mesh, CAM procedures for direct laser-sintering of the customized titanium mesh, and surgical insertion of the device. Using a computed tomography data set, the normal, uninjured side of the craniofacial skeleton was reflected onto the contralateral injured side, and a reconstructive orbital floor mesh was designed virtually on the mirrored orbital bone surface. The solid-to-layer files of the mesh were then manufactured using direct metal laser sintering, which resolves the shaping and bending biases inherent in the indirect method. An intraoperative navigation system ensured accuracy of the entire procedure. Clinical outcomes were assessed using 3dMD photogrammetry and computed tomography data in 7 treated patients. The technique described here appears to be a viable method to correct complex orbital floor defects needing delayed reconstruction. This study represents the first step in the development of a wider experimental protocol for orbital floor reconstruction using computer-assisted design-computer-assisted manufacturing technology.

3-D image reconstruction in radiology

International Nuclear Information System (INIS)

Grangeat, P.

1999-01-01

In this course, we present highlights on fully 3-D image reconstruction algorithms used in 3-D X-ray Computed Tomography (3-D-CT) and 3-D Rotational Radiography (3-D-RR). We first consider the case of spiral CT with a one-row detector. Starting from the 2-D fan-beam inversion formula for a circular trajectory, we introduce spiral CT 3-D image reconstruction algorithm using axial interpolation for each transverse slice. In order to improve the X-ray detection efficiency and to speed the acquisition process, the future is to use multi-row detectors associated with small angle cone-beam geometry. The generalization of the 2-D fan-beam image reconstruction algorithm to cone beam defined direct inversion formula referred as Feldkamp's algorithm for a circular trajectory and Wang's algorithm for a spiral trajectory. However, large area detectors does exist such as Radiological Image Intensifiers or in a near future solid state detectors. To get a larger zoom effect, it defines a cone-beam geometry associated with a large aperture angle. For this case, we introduce indirect image reconstruction algorithm by plane re-binning in the Radon domain. We will present some results from a prototype MORPHOMETER device using the RADON reconstruction software. Lastly, we consider the special case of 3-D Rotational Digital Subtraction Angiography with a restricted number of views. We introduce constraint optimization algorithm using quadratic, entropic or half-quadratic constraints. Generalized ART (Algebraic Reconstruction Technique) iterative reconstruction algorithm can be derived from the Bregman algorithm. We present reconstructed vascular trees from a prototype MORPHOMETER device. (author)

Sensation Following Immediate Breast Reconstruction with Implants.

Science.gov (United States)

Lagergren, Jakob; Wickman, Marie; Hansson, Per

2010-01-01

Sensation is a neglected aspect of the outcome of breast reconstructions with implants. The aim of this prospective study was to evaluate the cutaneous somatosensory status in breasts following mastectomy and immediate reconstruction with permanent adjustable prostheses and to analyze the patients' subjective experience of the sensation. Twenty-four consecutive patients diagnosed with invasive or in situ breast carcinoma were examined preoperatively and 2 years after mastectomy and reconstruction, for assessment of perception thresholds for touch, cold, warmth, and heat pain above and below the areola. Von Frey filaments and a Peltier element-based thermode were used. The patients completed a questionnaire concerning their experienced sensation in the reconstructed breast. Using quantitative somato-sensory testing, the sensation to all the examined modalities was significantly impaired compared to preoperatively. Most affected was the area above the areola. Patients given postoperative radiotherapy (n = 9) did not differ from those without radiotherapy (n = 15) regarding any of the modalities. All patients reported reduced sensation in the reconstructed breast compared to that preoperatively. Twenty-three patients stated that the reconstructed breast felt different from the other breast; nevertheless 16 reported that the reconstructed breast felt like a real breast. The study revealed sensation impairment following mastectomy and immediate reconstruction with implants. Patients should be informed about this effect preoperatively to allow adequate expectations regarding the sensation outcome. However, two-thirds of the study patients considered that the reconstructed breast felt like a real breast, which must be one of the main purposes of a breast reconstruction.

Atmospheric dispersion and deposition of 131I released from the Hanford Site

International Nuclear Information System (INIS)

Ramsdell, J.V. Jr.; Simonen, C.A.; Burk, K.W.; Stage, S.A.

1996-01-01

Approximately 2.6 x 10 4 TBq (700,000 Ci) of 131 I were released to the air from reactor fuel processing plants on the Hanford Site in southcentral Washington State from December 1944 through December 1949. The Hanford Environmental Dose Reconstruction Project developed a suite of codes to estimate the doses that might have resulted from these releases. The Regional Atmospheric Transport Code for Hanford Emission Tracking (RATCHET) computer code is part of this suite. The RATCHET code implements a Lagrangian-trajectory, Gaussian-puff dispersion model that uses hourly meterological and release rate data to estimate daily time-integrated air concentrations and surface contamination for use, in dose estimates. In this model, iodine is treated as a mixture of three species (inorganic gases, organic gases, and particles). Model deposition parameters are functions of the mixture and meterological conditions. A resistance model is used to calculate dry deposition velocities. Equilibrium between concentrations in the precipitation and the air near the ground is assumed in calculating wet deposition of gases, and irreversible washout of the particles is assumed. RATCHET explicitly treats the uncertainties in model parameters and meteorological conditions. Uncertainties in 131 I release rates and partitioning among the nominal species are treated by varying model input. The results of 100 model runs for December 1944 through December 1949 indicate that monthly average air concentrations and deposition have uncertainties ranging from a factor of two near the center of the time-integrated plume to more than an order of magnitude near the edge. These results indicate that ∼10% of the 131 I released to the atmosphere decayed during transit in the study area, ∼56% was deposited within the study area, and the remaining 34% was transported out of the study area while still in the air

No economic benefit of early knee reconstruction over optional delayed reconstruction for ACL tears

DEFF Research Database (Denmark)

Kiadaliri, Aliasghar A; Englund, Martin; Stefan Lohmander, L.

2016-01-01

Background To analyse 5-year cost-effectiveness of early versus optional delayed acute anterior cruciate ligament (ACL) reconstruction. Methods 121 young, active adults with acute ACL injury to a previously uninjured knee were randomised to early ACL reconstruction (n=62, within 10 weeks of injur...

Controversies in orbital reconstruction-III. Biomaterials for orbital reconstruction : a review with clinical recommendations

NARCIS (Netherlands)

Dubois, L.; Steenen, S. A.; Gooris, P. J. J.; Bos, R. R. M.; Becking, A. G.

The goal of orbital reconstruction is to repair trauma defects, to correct the position of the eye anatomically, avoiding enophthalmos, and to restore ocular function. For the reconstruction of (trauma) defects, many surgeons recommend materials that can be bent into an anatomical shape and that

Breast reconstruction and post-mastectomy radiation practice

International Nuclear Information System (INIS)

Chen, Susie A; Hiley, Crispin; Nickleach, Dana; Petsuksiri, Janjira; Andic, Fundagul; Riesterer, Oliver; Switchenko, Jeffrey M; Torres, Mylin A

2013-01-01

The goal of this study was to explore the perspectives and practice of radiation oncologists who treat breast cancer patients who have had breast reconstruction. In 2010, an original electronic survey was sent to all physician members of the American Society of Radiation Oncology, National Cancer Research Institute-Breast Cancer Studies Group in the United Kingdom, Thai Society of Therapeutic Radiology and Oncology, Swiss Society of Radiation Oncology, and Turkish Radiation Oncology Society. We identified factors associated with radiation oncologists who treat breast cancer patients with reconstruction performed prior to radiation and obtained information regarding radiation management of the breast reconstruction. 358 radiation oncologists responded, and 60% of the physicians were from the United States. While 64% of participants agree or strongly agree that breast image affects a woman’s quality of life during radiation, 57% feel that reconstruction challenges their ability to deliver effective breast radiation. Compared with other countries, treatment within the United States was associated with a high reconstruction rate (>/= 50% of mastectomy patients) prior to radiation (p < 0.05). Delayed-immediate reconstruction with a temporary tissue expander was more common in the United States than in other countries (52% vs. 23%, p = 0.01). Among physicians who treat patients with tissue expanders, the majority (60%) prefer a moderately inflated implant with 150-250 cc of fluid rather than a completely deflated (13%) or inflated expander (28%) during radiation. Among radiation oncologists who treat reconstructions, 49% never use bolus and 40% never boost a breast reconstruction. United States physicians were more likely than physicians from other countries to boost or bolus the reconstruction irrespective of the type of reconstruction seen in their clinic patients (p < 0.01). Great variation in practice is evident from our study of radiation treatment for breast

Boomerang flap reconstruction for the breast.

Science.gov (United States)

Baumholtz, Michael A; Al-Shunnar, Buthainah M; Dabb, Richard W

2002-07-01

The boomerang-shaped latissimus dorsi musculocutaneous flap for breast reconstruction offers a stable platform for breast reconstruction. It allows for maximal aesthetic results with minimal complications. The authors describe a skin paddle to obtain a larger volume than either the traditional elliptical skin paddle or the extended latissimus flap. There are three specific advantages to the boomerang design: large volume, conical shape (often lacking in the traditional skin paddle), and an acceptable donor scar. Thirty-eight flaps were performed. No reconstruction interfered with patient's ongoing oncological regimen. The most common complication was seroma, which is consistent with other latissimus reconstructions.

The Quebec Liberation Front (FLQ) as an Insurgency

Science.gov (United States)

2010-04-08

Histoire d’un mouvement clandestin, rev. ed. (Outremont, QC: Lanctôt Éditeur, 1998), 11. 4 targeted union workers and students. They also represented...Washington, DC: Government Printing Office, 2006. Fournier, Louis. FLQ: Histoire d’un mouvement clandestin. Rev. ed. Outremont, QC: Lanctôt Éditeur

Additive manufacturing technology in reconstructive surgery.

Science.gov (United States)

Fuller, Scott C; Moore, Michael G

2016-10-01

Technological advances have been part and parcel of modern reconstructive surgery, in that practitioners of this discipline are continually looking for innovative ways to perfect their craft and improve patient outcomes. We are currently in a technological climate wherein advances in computers, imaging, and science have coalesced with resulting innovative breakthroughs that are not merely limited to improved outcomes and enhanced patient care, but may provide novel approaches to training the next generation of reconstructive surgeons. New developments in software and modeling platforms, imaging modalities, tissue engineering, additive manufacturing, and customization of implants are poised to revolutionize the field of reconstructive surgery. The interface between technological advances and reconstructive surgery continues to expand. Additive manufacturing techniques continue to evolve in an effort to improve patient outcomes, decrease operative time, and serve as instructional tools for the training of reconstructive surgeons.

Complications in Postmastectomy Breast Reconstruction: One-year Outcomes of the Mastectomy Reconstruction Outcomes Consortium (MROC) Study.

Science.gov (United States)

Wilkins, Edwin G; Hamill, Jennifer B; Kim, Hyungjin M; Kim, John Y; Greco, Richard J; Qi, Ji; Pusic, Andrea L

2018-01-01

In postmastectomy reconstruction, procedure choice is heavily influenced by the relative risks of the various options. This study sought to evaluate complications in a large, multicenter patient population. Previous studies have reported widely varying complication rates, but have been limited by their single center designs and inadequate controlling for confounders in their analyses. Eleven sites enrolled women undergoing first time, immediate, or delayed reconstruction following mastectomy for cancer treatment or prophylaxis. Procedures included expander/implant, latissimus dorsi (LD), pedicle transverse rectus abdominis musculocutaneous (PTRAM), free TRAM (FTRAM), and deep inferior epigastric perforator (DIEP) techniques. Data were gathered pre- and postoperatively from medical records. Separate logistic regressions were conducted for all complications and major complications (those requiring rehospitalization and/or reoperation) within 1 year. Odds ratios (ORs) were calculated for procedure type, controlling for site, demographic, and clinical variables. Complication rates for 2234 patients were analyzed. Compared with expander/implant reconstructions, LD (OR) 1.95, P = 0.026), PTRAM (OR 1.89, P = 0.025), FTRAM (OR 1.94, P = 0.011), and DIEP (OR 2.22, P procedures were associated with higher risks of complications. Significantly higher risks were also associated with older age, higher body mass index (BMI), immediate reconstruction, bilateral procedures, and radiation. For major complications, regression showed significantly greater risks for PTRAM (OR 1.86, P = 0.044) and DIEP (OR 1.75, P = 0.004), than expander/implant reconstructions. Failure rates were relatively low, ranging from 0% for PTRAM to 5.9% for expander/implant reconstructions. In this multicenter analysis, procedure choice and other patient variables were significant predictors of 1-year complications in breast reconstruction. These findings should be considered in counseling patients on

Progressive Reconstruction: A Methodology for Stabilization and Reconstruction Operations

National Research Council Canada - National Science Library

Rohr, Karl C

2006-01-01

... these nations in accordance with stated United States' goals. The argument follows closely current and developing United States military doctrine on stabilization, reconstruction, and counterinsurgency operations...

Titanium template for scaphoid reconstruction.

Science.gov (United States)

Haefeli, M; Schaefer, D J; Schumacher, R; Müller-Gerbl, M; Honigmann, P

2015-06-01

Reconstruction of a non-united scaphoid with a humpback deformity involves resection of the non-union followed by bone grafting and fixation of the fragments. Intraoperative control of the reconstruction is difficult owing to the complex three-dimensional shape of the scaphoid and the other carpal bones overlying the scaphoid on lateral radiographs. We developed a titanium template that fits exactly to the surfaces of the proximal and distal scaphoid poles to define their position relative to each other after resection of the non-union. The templates were designed on three-dimensional computed tomography reconstructions and manufactured using selective laser melting technology. Ten conserved human wrists were used to simulate the reconstruction. The achieved precision measured as the deviation of the surface of the reconstructed scaphoid from its virtual counterpart was good in five cases (maximal difference 1.5 mm), moderate in one case (maximal difference 3 mm) and inadequate in four cases (difference more than 3 mm). The main problems were attributed to the template design and can be avoided by improved pre-operative planning, as shown in a clinical case. © The Author(s) 2014.

Dynamic dual-tracer PET reconstruction.

Science.gov (United States)

Gao, Fei; Liu, Huafeng; Jian, Yiqiang; Shi, Pengcheng

2009-01-01

Although of important medical implications, simultaneous dual-tracer positron emission tomography reconstruction remains a challenging problem, primarily because the photon measurements from dual tracers are overlapped. In this paper, we propose a simultaneous dynamic dual-tracer reconstruction of tissue activity maps based on guidance from tracer kinetics. The dual-tracer reconstruction problem is formulated in a state-space representation, where parallel compartment models serve as continuous-time system equation describing the tracer kinetic processes of dual tracers, and the imaging data is expressed as discrete sampling of the system states in measurement equation. The image reconstruction problem has therefore become a state estimation problem in a continuous-discrete hybrid paradigm, and H infinity filtering is adopted as the estimation strategy. As H infinity filtering makes no assumptions on the system and measurement statistics, robust reconstruction results can be obtained for the dual-tracer PET imaging system where the statistical properties of measurement data and system uncertainty are not available a priori, even when there are disturbances in the kinetic parameters. Experimental results on digital phantoms, Monte Carlo simulations and physical phantoms have demonstrated the superior performance.

Connected Filtering by Reconstruction : Basis and New Advances

NARCIS (Netherlands)

Wilkinson, Michael H.F.

2008-01-01

Openings-by-reconstruction are the oldest connected filters, and indeed, reconstruction methodology lies at the heart of many connected operators such as levelings. Starting out from the basic reconstruction principle of iterated geodesic dilations, extensions such as the use of reconstruction

CONNECTED FILTERING BY RECONSTRUCTION : BASIS AND NEW ADVANCES

NARCIS (Netherlands)

Wilkinson, Michael H. F.

2008-01-01

Openings-by-reconstruction are the oldest connected filters, and indeed, reconstruction methodology lies at the heart of many connected operators such as levelings. Starting out from the basic reconstruction principle of iterated geodesic dilations, extensions such as the use of reconstruction

Tomographic reconstruction of binary fields

International Nuclear Information System (INIS)

Roux, Stéphane; Leclerc, Hugo; Hild, François

2012-01-01

A novel algorithm is proposed for reconstructing binary images from their projection along a set of different orientations. Based on a nonlinear transformation of the projection data, classical back-projection procedures can be used iteratively to converge to the sought image. A multiscale implementation allows for a faster convergence. The algorithm is tested on images up to 1 Mb definition, and an error free reconstruction is achieved with a very limited number of projection data, saving a factor of about 100 on the number of projections required for classical reconstruction algorithms.

Sustained-release progesterone vaginal suppositories 1--development of sustained-release granule--.

Science.gov (United States)

Nakayama, Ayako; Sunada, Hisakazu; Okamoto, Hirokazu; Furuhashi, Kaoru; Ohno, Yukiko; Ito, Mikio

2009-02-01

Progesterone (P) is an important hormone for the establishment of pregnancy, and its administration is useful for luteal insufficiency. Considering the problems of commercially available oral and injection drugs, hospital-formulated vaginal suppositories are clinically used. However, since the half-life of P suppositories is short, it is difficult to maintain its constant blood concentration. To sustain drug efficacy and prevent side-effects, we are attempting to develop sustained-release suppositories by examining the degree of sustained-release of active ingredients. In this study, we examined the combinations of granulation methods and release systems for the preparation of sustained-release granules of P, and produced 13 types of sustained-release granules. We also examined the diameter, content, and dissolution of each type of granules, and confirmed that the sustained-release of all types of granules was satisfactory. Among the sustained-release granules, we selected granules with a content and a degree of sustained-release suitable for sustained-release suppositories.

Labral reconstruction: when to perform and how

Directory of Open Access Journals (Sweden)

Brian J White

2015-07-01

Full Text Available Over the past decade, the understanding of the anatomy and function of the hip joint has continuously evolved, and surgical treatment options for the hip have significantly progressed. Originally, surgical treatment of the hip primarily involved resection of damaged tissue. Procedures that maintain and preserve proper hip anatomy, such as labral repair and femoroacetabular impingement (FAI correction, have shown superior results, in terms of pain reduction, increased function, and ability to return to activities. Labral reconstruction is a treatment option that uses a graft to reconstruct the native labrum. The technique and outcomes of labral reconstruction have been described relatively recently, and labral reconstruction is a cutting edge procedure that has shown promising early outcomes. The aim of this article is to review the current literature on hip labral reconstruction. We will review the indications for labral reconstruction, surgical technique and graft options, and surgical outcomes that have been described to date. Labral reconstruction provides an alternative treatment option for challenging intra-articular hip problems. Labral reconstruction restores the original anatomy of the hip and has the potential to preserve the longevity of the hip joint. This technique is an important tool in the orthopaedic surgeon’s arsenal for hip joint treatment and preservation.

CURRENT CONCEPTS IN ACL RECONSTRUCTION

Directory of Open Access Journals (Sweden)

Freddie H. Fu

2008-09-01

Full Text Available Current Concepts in ACL Reconstruction is a complete reference text composed of the most thorough collection of topics on the ACL and its surgical reconstruction compiled, with contributions from some of the world's experts and most experienced ACL surgeons. Various procedures mentioned throughout the text are also demonstrated in an accompanying video CD-ROM. PURPOSE Composing a single, comprehensive and complete information source on ACL including basic sciences, clinical issues, latest concepts and surgical techniques, from evaluation to outcome, from history to future, editors and contributors have targeted to keep the audience pace with the latest concepts and techniques for the evaluation and the treatment of ACL injuries. FEATURES The text is composed of 27 chapters in 6 sections. The first section is mostly about basic sciences, also history of the ACL, imaging, clinical approach to adolescent and pediatric patients are subjected. In the second section, Graft Choices and Arthroscopy Portals for ACL Reconstruction are mentioned. The third section is about the technique and the outcome of the single-bundle ACL reconstruction. The fourth chapter includes the techniques and outcome of the double-bundle ACL reconstruction. In the fifth chapter revision, navigation technology, rehabilitation and the evaluation of the outcome of ACL reconstruction is subjected. The sixth/the last chapter is about the future advances to reach: What We Have Learned and the Future of ACL Reconstruction. AUDIENCE Orthopedic residents, sports traumatology and knee surgery fellows, orthopedic surgeons, also scientists in basic sciences or clinicians who are studying or planning a research on ACL forms the audience group of this book. ASSESSMENT This is the latest, the most complete and comprehensive textbook of ACL reconstruction produced by the editorial work up of two pioneer and masters "Freddie H. Fu MD and Steven B. Cohen MD" with the contribution of world

Climate Reconstructions

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Paleoclimatology Program archives reconstructions of past climatic conditions derived from paleoclimate proxies, in addition to the Program's large holdings...

Top reconstruction and boosted top experimental overview

CERN Document Server

Skinnari, Louise

2015-01-01

An overview of techniques used to reconstruct resolved and boosted top quarks is presented. Techniques for resolved top quark reconstruction include kinematic likelihood fitters and pseudo- top reconstruction. Many tools and methods are available for the reconstruction of boosted top quarks, such as jet grooming techniques, jet substructure variables, and dedicated top taggers. Different techniques as used by ATLAS and CMS analyses are described and the performance of different variables and top taggers are shown.

Sparse Image Reconstruction in Computed Tomography

DEFF Research Database (Denmark)

Jørgensen, Jakob Sauer

In recent years, increased focus on the potentially harmful effects of x-ray computed tomography (CT) scans, such as radiation-induced cancer, has motivated research on new low-dose imaging techniques. Sparse image reconstruction methods, as studied for instance in the field of compressed sensing...... applications. This thesis takes a systematic approach toward establishing quantitative understanding of conditions for sparse reconstruction to work well in CT. A general framework for analyzing sparse reconstruction methods in CT is introduced and two sets of computational tools are proposed: 1...... contributions to a general set of computational characterization tools. Thus, the thesis contributions help advance sparse reconstruction methods toward routine use in...

Medical image reconstruction. A conceptual tutorial

International Nuclear Information System (INIS)

Zeng, Gengsheng Lawrence

2010-01-01

''Medical Image Reconstruction: A Conceptual Tutorial'' introduces the classical and modern image reconstruction technologies, such as two-dimensional (2D) parallel-beam and fan-beam imaging, three-dimensional (3D) parallel ray, parallel plane, and cone-beam imaging. This book presents both analytical and iterative methods of these technologies and their applications in X-ray CT (computed tomography), SPECT (single photon emission computed tomography), PET (positron emission tomography), and MRI (magnetic resonance imaging). Contemporary research results in exact region-of-interest (ROI) reconstruction with truncated projections, Katsevich's cone-beam filtered backprojection algorithm, and reconstruction with highly undersampled data with l 0 -minimization are also included. (orig.)

Reconstruction design before tumour resection: A new concept of through-and-through cheek defect reconstruction.

Science.gov (United States)

Gong, Zhao-Jian; Ren, Zhen-Hu; Wang, Kai; Tan, Hong-Yu; Zhang, Sheng; Wu, Han-Jiang

2017-11-01

To explore a new method of reconstruction of through-and-through cheek defects and to evaluate this method's efficacy and patient prognosis. This retrospective study included 70 patients who underwent reconstruction of through-and-through cheek defects. The surgical approach, design of facial skin incisions, selection and design of flaps, postoperative quality of life and prognosis of patients were recorded and reported. Postoperative quality of life gradually increased over time, and the mean scores of University of Washington Quality of Life (UW-QOL) Questionnaire was more than 80 at 1-year postoperatively. The appearance, oral competence, chewing, swallowing, speech and other oral functions were well recovered in about 90% of patients at 1-year postoperatively. This new idea of reconstruction before tumour resection, brings the effect of plastic and reconstructive surgery to a new height. Copyright © 2017. Published by Elsevier Ltd.

Considerations on Xi- reconstruction in LHCb

CERN Document Server

Brochu, F.M.

2016-01-01

This paper describes an alternative method of charged hyperon reconstruction applicable to the LHCb experiment. It extends the seminal work of the FOCUS collaboration to the specific detector layout of LHCb and addresses the reconstruction ambiguities reported in their earlier work, leading to improvements in the reconstruction efficiency for the specific cases of Xi- and Omega- baryon decays to a charged meson and a Lambda baryon.

A biomechanical modeling-guided simultaneous motion estimation and image reconstruction technique (SMEIR-Bio) for 4D-CBCT reconstruction

Science.gov (United States)

Huang, Xiaokun; Zhang, You; Wang, Jing

2018-02-01

Reconstructing four-dimensional cone-beam computed tomography (4D-CBCT) images directly from respiratory phase-sorted traditional 3D-CBCT projections can capture target motion trajectory, reduce motion artifacts, and reduce imaging dose and time. However, the limited numbers of projections in each phase after phase-sorting decreases CBCT image quality under traditional reconstruction techniques. To address this problem, we developed a simultaneous motion estimation and image reconstruction (SMEIR) algorithm, an iterative method that can reconstruct higher quality 4D-CBCT images from limited projections using an inter-phase intensity-driven motion model. However, the accuracy of the intensity-driven motion model is limited in regions with fine details whose quality is degraded due to insufficient projection number, which consequently degrades the reconstructed image quality in corresponding regions. In this study, we developed a new 4D-CBCT reconstruction algorithm by introducing biomechanical modeling into SMEIR (SMEIR-Bio) to boost the accuracy of the motion model in regions with small fine structures. The biomechanical modeling uses tetrahedral meshes to model organs of interest and solves internal organ motion using tissue elasticity parameters and mesh boundary conditions. This physics-driven approach enhances the accuracy of solved motion in the organ’s fine structures regions. This study used 11 lung patient cases to evaluate the performance of SMEIR-Bio, making both qualitative and quantitative comparisons between SMEIR-Bio, SMEIR, and the algebraic reconstruction technique with total variation regularization (ART-TV). The reconstruction results suggest that SMEIR-Bio improves the motion model’s accuracy in regions containing small fine details, which consequently enhances the accuracy and quality of the reconstructed 4D-CBCT images.

HPLC analysis of potentially harmful substances released from dental filing aterials available on the EU market

Directory of Open Access Journals (Sweden)

Konrad Małkiewicz

2014-03-01

Full Text Available Introduction. Incomplete cross-linking of composite dental materials leads to their susceptibility to degradation in the environment of non-organic and organic solvents, contributing to the release of chemical compounds which are potentially harmful to living organisms. Objective. The aim of the study was an evaluation in in vitro conditions of releasing of potentially toxic substances from six dental composite materials available in EU countries. Materials and methods. The following compounds released from the samples stored in water were analyzed: bisphenol A (BPA, triethylene glycol-dimethacrylate (TEGDMA, urethane dimethacrylate (UDMA and ethylene glycol dimethacrylate (EDGMA. Analysis of the substances was performed with the use of high performance liquid chromatography, after the following incubation periods: 1 hour, 24 hours, 7 days and 30 days. Results. Among the analyzed substances, after 1 hour of incubation, the highest average concentration was found for TEGDMA – 2045 μg cm-3 (in Herculite XRV material, after 24 hours – for UDMA 4.402 μg cm-3 (in Gradia Direct Anterior material and after 7 and 30 days for TEGDMA: 8.112 and 6.458 μg•cm-3 respectively (in Charisma material. Conclusions. The examined composites used for reconstruction of hard tissues of teeth remain chemically unstable after polymerization, and release potentially harmful substances in conditions of the present study. The dynamics of the releasing of potentially harmful substances is correlated with the period of sample storage in water.

Updates in Head and Neck Reconstruction.

Science.gov (United States)

Largo, Rene D; Garvey, Patrick B

2018-02-01

After reading this article, the participant should be able to: 1. Have a basic understanding of virtual planning, rapid prototype modeling, three-dimensional printing, and computer-assisted design and manufacture. 2. Understand the principles of combining virtual planning and vascular mapping. 3. Understand principles of flap choice and design in preoperative planning of free osteocutaneous flaps in mandible and midface reconstruction. 4. Discuss advantages and disadvantages of computer-assisted design and manufacture in reconstruction of advanced oncologic mandible and midface defects. Virtual planning and rapid prototype modeling are increasingly used in head and neck reconstruction with the aim of achieving superior surgical outcomes in functionally and aesthetically critical areas of the head and neck compared with conventional reconstruction. The reconstructive surgeon must be able to understand this rapidly-advancing technology, along with its advantages and disadvantages. There is no limit to the degree to which patient-specific data may be integrated into the virtual planning process. For example, vascular mapping can be incorporated into virtual planning of mandible or midface reconstruction. Representative mandible and midface cases are presented to illustrate the process of virtual planning. Although virtual planning has become helpful in head and neck reconstruction, its routine use may be limited by logistic challenges, increased acquisition costs, and limited flexibility for intraoperative modifications. Nevertheless, the authors believe that the superior functional and aesthetic results realized with virtual planning outweigh the limitations.

OSCAAR calculations for the Hanford dose reconstruction scenario of BIOMASS Theme 2

International Nuclear Information System (INIS)

Homma, Toshimitsu; Tomita, Kenichi

2000-10-01

This report presents the results obtained from the application of the accident consequence assessment code, called OSCAAR, developed in Japan Atomic Energy Research Institute to the Hanford dose reconstruction scenario of BIOMASS Theme 2 organized by International Atomic Energy Agency. The scenario relates to an inadvertent release of 131 I to atmosphere from the Hanford Purex Chemical Separations Plant on 2-5 September 1963. This exercise was used to test the atmospheric dispersion and deposition models and food chain transport models for 131 I in OSCAAR with actual measurements and to identify the most important sources of uncertainty with respect both to the part of the assessment and to the overall assessment. The OSCAAR food chain model performed relatively well, while the atmospheric dispersion and deposition calculations made using wind data at the release height and wind fields by simple interpolation of the surrounding surface wind data indicated limited capabilities. The Monte Carlo based uncertainty and sensitivity method linked with OSCAAR successfully demonstrated its usefulness in the scenario. The method presented here also allowed the determination of the parameters that have the most important impact in accident consequence assessments. (author)

OSCAAR calculations for the Hanford dose reconstruction scenario of BIOMASS Theme 2

Energy Technology Data Exchange (ETDEWEB)

Homma, Toshimitsu; Tomita, Kenichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Inoue, Yoshihisa [Visible Information Center Inc., Tokai, Ibaraki (Japan)

2000-10-01

This report presents the results obtained from the application of the accident consequence assessment code, called OSCAAR, developed in Japan Atomic Energy Research Institute to the Hanford dose reconstruction scenario of BIOMASS Theme 2 organized by International Atomic Energy Agency. The scenario relates to an inadvertent release of {sup 131}I to atmosphere from the Hanford Purex Chemical Separations Plant on 2-5 September 1963. This exercise was used to test the atmospheric dispersion and deposition models and food chain transport models for {sup 131}I in OSCAAR with actual measurements and to identify the most important sources of uncertainty with respect both to the part of the assessment and to the overall assessment. The OSCAAR food chain model performed relatively well, while the atmospheric dispersion and deposition calculations made using wind data at the release height and wind fields by simple interpolation of the surrounding surface wind data indicated limited capabilities. The Monte Carlo based uncertainty and sensitivity method linked with OSCAAR successfully demonstrated its usefulness in the scenario. The method presented here also allowed the determination of the parameters that have the most important impact in accident consequence assessments. (author)

Secondary reconstruction of maxillofacial trauma.

Science.gov (United States)

Castro-Núñez, Jaime; Van Sickels, Joseph E

2017-08-01

Craniomaxillofacial trauma is one of the most complex clinical conditions in contemporary maxillofacial surgery. Vital structures and possible functional and esthetic sequelae are important considerations following this type of trauma and intervention. Despite the best efforts of the primary surgery, there are a group of patients that will have poor outcomes requiring secondary reconstruction to restore form and function. The purpose of this study is to review current concepts on secondary reconstruction to the maxillofacial complex. The evaluation of a posttraumatic patient for a secondary reconstruction must include an assessment of the different subunits of the upper face, middle face, and lower face. Virtual surgical planning and surgical guides represent the most important innovations in secondary reconstruction over the past few years. Intraoperative navigational surgery/computed-assisted navigation is used in complex cases. Facial asymmetry can be corrected or significantly improved by segmentation of the computerized tomography dataset and mirroring of the unaffected side by means of virtual surgical planning. Navigational surgery/computed-assisted navigation allows for a more precise surgical correction when secondary reconstruction involves the replacement of extensive anatomical areas. The use of technology can result in custom-made replacements and prebent plates, which are more stable and resistant to fracture because of metal fatigue. Careful perioperative evaluation is the key to positive outcomes of secondary reconstruction after trauma. The advent of technological tools has played a capital role in helping the surgical team perform a given treatment plan in a more precise and predictable manner.

Clinical applications of iterative reconstruction

International Nuclear Information System (INIS)

Eberl, S.

1998-01-01

Expectation maximisation (EM) reconstruction largely eliminates the hot and cold streaking artifacts characteristic of filtered-back projection (FBP) reconstruction around localised hot areas, such as the bladder. It also substantially reduces the problem of decreased inferior wall counts in MIBI myocardial perfusion studies due to ''streaking'' from high liver uptake. Non-uniform attenuation and scatter correction, resolution recovery, anatomical information, e.g. from MRI or CT tracer kinetic modelling, can all be built into the EM reconstruction imaging model. The properties of ordered subset EM (OSEM) have also been used to correct for known patient motion as part of the reconstruction process. These uses of EM are elaborated more fully in some of the other abstracts of this meeting. Currently we use OSEM routinely for: (i) studies where streaking is a problem, including all MIBI myocardial perfusion studies, to avoid hot liver inferior wall artifact, (ii) all whole body FDG PET, all lung V/Q SPECT (which have a short acquisition time) and all gated 201 TI myocardial perfusion studies due to improved noise characteristics of OSEM in these studies; (iii) studies with measured, non-uniform attenuation correction. With the accelerated OSEM algorithm, iterative reconstruction is practical for routine clinical applications and we have found OSEM to provide clearly superior reconstructions for the areas listed above and are investigating its application to other studies. In clinical use, we have not found OSEM to introduce artifacts which would not also occur with FBP, e.g. uncorrected patient motion will cause artifacts with both OSEM and FBP

Polaron-Driven Surface Reconstructions

Directory of Open Access Journals (Sweden)

Michele Reticcioli

2017-09-01

Full Text Available Geometric and electronic surface reconstructions determine the physical and chemical properties of surfaces and, consequently, their functionality in applications. The reconstruction of a surface minimizes its surface free energy in otherwise thermodynamically unstable situations, typically caused by dangling bonds, lattice stress, or a divergent surface potential, and it is achieved by a cooperative modification of the atomic and electronic structure. Here, we combined first-principles calculations and surface techniques (scanning tunneling microscopy, non-contact atomic force microscopy, scanning tunneling spectroscopy to report that the repulsion between negatively charged polaronic quasiparticles, formed by the interaction between excess electrons and the lattice phonon field, plays a key role in surface reconstructions. As a paradigmatic example, we explain the (1×1 to (1×2 transition in rutile TiO_{2}(110.

MR image reconstruction via guided filter.

Science.gov (United States)

Huang, Heyan; Yang, Hang; Wang, Kang

2018-04-01

Magnetic resonance imaging (MRI) reconstruction from the smallest possible set of Fourier samples has been a difficult problem in medical imaging field. In our paper, we present a new approach based on a guided filter for efficient MRI recovery algorithm. The guided filter is an edge-preserving smoothing operator and has better behaviors near edges than the bilateral filter. Our reconstruction method is consist of two steps. First, we propose two cost functions which could be computed efficiently and thus obtain two different images. Second, the guided filter is used with these two obtained images for efficient edge-preserving filtering, and one image is used as the guidance image, the other one is used as a filtered image in the guided filter. In our reconstruction algorithm, we can obtain more details by introducing guided filter. We compare our reconstruction algorithm with some competitive MRI reconstruction techniques in terms of PSNR and visual quality. Simulation results are given to show the performance of our new method.

Fabrication and characterization of a rapid prototyped tissue engineering scaffold with embedded multicomponent matrix for controlled drug release

Science.gov (United States)

Chen, Muwan; Le, Dang QS; Hein, San; Li, Pengcheng; Nygaard, Jens V; Kassem, Moustapha; Kjems, Jørgen; Besenbacher, Flemming; Bünger, Cody

2012-01-01

Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone scaffold was embedded with a porous matrix composed of chitosan, nanoclay, and β-tricalcium phosphate by freeze-drying. This composite scaffold was evaluated on its ability to deliver an anthracycline antibiotic and to promote formation of mineralized matrix in vitro. Scanning electronic microscopy, confocal imaging, and DNA quantification confirmed that immortalized human bone marrow-derived mesenchymal stem cells (hMSC-TERT) cultured in the scaffold showed high cell viability and growth, and good cell infiltration to the pores of the scaffold. Alkaline phosphatase activity and osteocalcin staining showed that the scaffold was osteoinductive. The drug-release kinetics was investigated by loading doxorubicin into the scaffold. The scaffolds comprising nanoclay released up to 45% of the drug for up to 2 months, while the scaffold without nanoclay released 95% of the drug within 4 days. Therefore, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount of individual components, the scaffold can find application in other tissue engineering areas that need local sustained release of drug. PMID:22904634

High resolution x-ray CMT: Reconstruction methods

Energy Technology Data Exchange (ETDEWEB)

Brown, J.K.

1997-02-01

This paper qualitatively discusses the primary characteristics of methods for reconstructing tomographic images from a set of projections. These reconstruction methods can be categorized as either {open_quotes}analytic{close_quotes} or {open_quotes}iterative{close_quotes} techniques. Analytic algorithms are derived from the formal inversion of equations describing the imaging process, while iterative algorithms incorporate a model of the imaging process and provide a mechanism to iteratively improve image estimates. Analytic reconstruction algorithms are typically computationally more efficient than iterative methods; however, analytic algorithms are available for a relatively limited set of imaging geometries and situations. Thus, the framework of iterative reconstruction methods is better suited for high accuracy, tomographic reconstruction codes.

A fast image reconstruction technique based on ART

International Nuclear Information System (INIS)

Zhang Shunli; Zhang Dinghua; Wang Kai; Huang Kuidong; Li Weibin

2007-01-01

Algebraic Reconstruction Technique (ART) is an iterative method for image reconstruction. Improving its reconstruction speed has been one of the important researching aspects of ART. For the simplified weight coefficients reconstruction model of ART, a fast grid traverse algorithm is proposed, which can determine the grid index by simple operations such as addition, subtraction and comparison. Since the weight coefficients are calculated at real time during iteration, large amount of storage is saved and the reconstruction speed is greatly increased. Experimental results show that the new algorithm is very effective and the reconstruction speed is improved about 10 times compared with the traditional algorithm. (authors)

Flip-avoiding interpolating surface registration for skull reconstruction.

Science.gov (United States)

Xie, Shudong; Leow, Wee Kheng; Lee, Hanjing; Lim, Thiam Chye

2018-03-30

Skull reconstruction is an important and challenging task in craniofacial surgery planning, forensic investigation and anthropological studies. Existing methods typically reconstruct approximating surfaces that regard corresponding points on the target skull as soft constraints, thus incurring non-zero error even for non-defective parts and high overall reconstruction error. This paper proposes a novel geometric reconstruction method that non-rigidly registers an interpolating reference surface that regards corresponding target points as hard constraints, thus achieving low reconstruction error. To overcome the shortcoming of interpolating a surface, a flip-avoiding method is used to detect and exclude conflicting hard constraints that would otherwise cause surface patches to flip and self-intersect. Comprehensive test results show that our method is more accurate and robust than existing skull reconstruction methods. By incorporating symmetry constraints, it can produce more symmetric and normal results than other methods in reconstructing defective skulls with a large number of defects. It is robust against severe outliers such as radiation artifacts in computed tomography due to dental implants. In addition, test results also show that our method outperforms thin-plate spline for model resampling, which enables the active shape model to yield more accurate reconstruction results. As the reconstruction accuracy of defective parts varies with the use of different reference models, we also study the implication of reference model selection for skull reconstruction. Copyright © 2018 John Wiley & Sons, Ltd.

Vertex Reconstruction and Performance in ATLAS

CERN Document Server

Whitmore, Ben William; The ATLAS collaboration

2017-01-01

Efficient and precise reconstruction of the primary vertices in LHC collisions is essential in both the reconstruction of the full kinematic properties of a hard-scatter event and of soft interactions as a measure of the amount of pile-up. The reconstruction of the primary vertices in the busy, high pile up environment of the LHC is a challenging task. The challenges and novel methods developed by the ATLAS experiment to reconstruct vertices in such environments will be presented. The performance of the current vertexing algorithms using Run-2 data will be presented and compared to results from simulation. Additionally, data-driven methods to evaluate vertex resolution, and details of upgrades to the ATLAS inner detector will be presented.

The enterovirus 71 A-particle forms a gateway to allow genome release: a cryoEM study of picornavirus uncoating.

Directory of Open Access Journals (Sweden)

Kristin L Shingler

2013-03-01

Full Text Available Since its discovery in 1969, enterovirus 71 (EV71 has emerged as a serious worldwide health threat. This human pathogen of the picornavirus family causes hand, foot, and mouth disease, and also has the capacity to invade the central nervous system to cause severe disease and death. Upon binding to a host receptor on the cell surface, the virus begins a two-step uncoating process, first forming an expanded, altered "A-particle", which is primed for genome release. In a second step after endocytosis, an unknown trigger leads to RNA expulsion, generating an intact, empty capsid. Cryo-electron microscopy reconstructions of these two capsid states provide insight into the mechanics of genome release. The EV71 A-particle capsid interacts with the genome near the icosahedral two-fold axis of symmetry, which opens to the external environment via a channel ∼10 Å in diameter that is lined with patches of negatively charged residues. After the EV71 genome has been released, the two-fold channel shrinks, though the overall capsid dimensions are conserved. These structural characteristics identify the two-fold channel as the site where a gateway forms and regulates the process of genome release.

Reconstructing Nearly Simple Polytopes from their Graph

OpenAIRE

Doolittle, Joseph

2017-01-01

We present a partial description of which polytopes are reconstructible from their graphs. This is an extension of work by Blind and Mani (1987) and Kalai (1988), which showed that simple polytopes can be reconstructed from their graphs. In particular, we introduce a notion of $h$-nearly simple and prove that 1-nearly simple and 2-nearly simple polytopes are reconstructible from their graphs. We also give an example of a 3-nearly simple polytope which is not reconstructible from its graph. Fu...

Oak Ridge Health Studies Phase 1 report, Volume 2: Part A, Dose Reconstruction Feasibility Study

International Nuclear Information System (INIS)

Bruce, G.M.; Buddenbaum, J.E.; Lamb, J.K.; Widner, T.E.

1993-09-01

The Phase I feasibility study has focused on determining the availability of information for estimating exposures of the public to chemicals and radionuclides released as a result of historical operation of the facilities at the Oak Ridge Reservation (ORR). The estimation of such past exposures is frequently called dose reconstruction. The initial project tasks, Tasks 1 and 2 were designed to identify and collect information that documents the history of activities at the ORR that resulted in the release of contamination and to characterize the availability of data that could be used to estimate the magnitude of the contaminant releases or public exposures. A history of operations that are likely to have generated off-site releases has been documented as a result of Task 1 activities. The activities required to perform this task involved the extensive review of historical operation records and interviews with present and past employees as well as other knowledgeable individuals. The investigation process is documented in this report. The Task 1 investigations have led to the documentation of an overview of the activities that have taken place at each of the major complexes, including routine operations, waste management practices, special projects, and accidents and incidents. Historical activities that appear to warrant the highest priority in any further investigations were identified based on their likely association with off-site emissions of hazardous materials as indicated by the documentation reviewed or information obtained in interviews

Anatomic Double-bundle ACL Reconstruction

NARCIS (Netherlands)

Schreiber, Verena M.; van Eck, Carola F.; Fu, Freddie H.

2010-01-01

Rupture of the anterior cruciate ligament (ACL) is one of the most frequent forms of knee trauma. The traditional surgical treatment for ACL rupture is single-bundle reconstruction. However, during the past few years there has been a shift in interest toward double-bundle reconstruction to closely

Rational reconstructions of modern physics

CERN Document Server

Mittelstaedt, Peter

2013-01-01

Newton’s classical physics and its underlying ontology are loaded with several metaphysical hypotheses that cannot be justified by rational reasoning nor by experimental evidence. Furthermore, it is well known that some of these hypotheses are not contained in the great theories of Modern Physics, such as the theory of Special Relativity and Quantum Mechanics. This book shows that, on the basis of Newton’s classical physics and by rational reconstruction, the theory of Special Relativity as well as Quantum Mechanics can be obtained by partly eliminating or attenuating the metaphysical hypotheses. Moreover, it is shown that these reconstructions do not require additional hypotheses or new experimental results. In the second edition the rational reconstructions are completed with respect to General Relativity and Cosmology. In addition, the statistics of quantum objects is elaborated in more detail with respect to the rational reconstruction of quantum mechanics. The new material completes the approach of t...

Simulation and track reconstruction for beam telescopes

CERN Document Server

Maqbool, Salman

2017-01-01

Beam telescopes are used for testing new detectors under development. Sensors are placed and a particle beam is passed through them. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, it’s predicted hits on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them don’t account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framew...

Evaluation of proxy-based millennial reconstruction methods

Energy Technology Data Exchange (ETDEWEB)

Lee, Terry C.K.; Tsao, Min [University of Victoria, Department of Mathematics and Statistics, Victoria, BC (Canada); Zwiers, Francis W. [Environment Canada, Climate Research Division, Toronto, ON (Canada)

2008-08-15

A range of existing statistical approaches for reconstructing historical temperature variations from proxy data are compared using both climate model data and real-world paleoclimate proxy data. We also propose a new method for reconstruction that is based on a state-space time series model and Kalman filter algorithm. The state-space modelling approach and the recently developed RegEM method generally perform better than their competitors when reconstructing interannual variations in Northern Hemispheric mean surface air temperature. On the other hand, a variety of methods are seen to perform well when reconstructing surface air temperature variability on decadal time scales. An advantage of the new method is that it can incorporate additional, non-temperature, information into the reconstruction, such as the estimated response to external forcing, thereby permitting a simultaneous reconstruction and detection analysis as well as future projection. An application of these extensions is also demonstrated in the paper. (orig.)

Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction.

Science.gov (United States)

Fink, Christian; Steensen, Robert; Gföller, Peter; Lawton, Robert

2018-06-01

Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction. Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics. Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

Simulation and Track Reconstruction for Beam Telescopes

CERN Document Server

Maqbool, Salman

2017-01-01

Beam telescopes are an important tool to test new detectors under development in a particle beam. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, its predicted position on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them do not account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framework along with the General Broken ...

Method for position emission mammography image reconstruction

Science.gov (United States)

Smith, Mark Frederick

2004-10-12

An image reconstruction method comprising accepting coincidence datat from either a data file or in real time from a pair of detector heads, culling event data that is outside a desired energy range, optionally saving the desired data for each detector position or for each pair of detector pixels on the two detector heads, and then reconstructing the image either by backprojection image reconstruction or by iterative image reconstruction. In the backprojection image reconstruction mode, rays are traced between centers of lines of response (LOR's), counts are then either allocated by nearest pixel interpolation or allocated by an overlap method and then corrected for geometric effects and attenuation and the data file updated. If the iterative image reconstruction option is selected, one implementation is to compute a grid Siddon retracing, and to perform maximum likelihood expectation maiximization (MLEM) computed by either: a) tracing parallel rays between subpixels on opposite detector heads; or b) tracing rays between randomized endpoint locations on opposite detector heads.

“Basket weave technique” for medial patellofemoral ligament reconstruction: Clinical outcome of a prospective study

Science.gov (United States)

Kodkani, Pranjal S

2016-01-01

Background: Bone tunneling and implants with rigid fixations for medial patellofemoral ligament (MPFL) reconstruction are known to compromise results and are avoidable, especially in skeletally immature subjects. This study was to assess if these deficiencies were overcome with the technique devised by the author which avoids implants and bone tunnels. Results were assessed for complication rate and outcome. Materials and Methods: Fifty six knees of recurrent lateral patellar dislocation were treated in the past 49 months by MPFL reconstruction. Thirty nine were female and 17 male knees. The mean age was 20.6 years (range 9-48 years). Mean followup was 26 months. Five knees had previously failed stabilization procedures. Thirty one cases had Dejours Type A or B and 12 had Type C trochlear dysplasia. Arthroscopy was performed for associated injuries and loose bodies. Seven knees required loose body removal. Five knees underwent lateral retinacular release. Four knees had tibial tuberosity transfer. One knee had an associated anterior cruciate ligament reconstruction. An anatomical MPFL reconstruction was performed using hamstring autograft without the need for intraoperative fluoroscopy. Only soft tissue fixation was necessary with this newly devised technique and suturing. A rapid rehabilitation protocol was implemented with monthly followup until normalcy and 6 monthly thereafter. Results: All achieved full range of motion and normal mediolateral stability. There was no recurrence of dislocation. No major surgery related complications. One patella fracture at 8 months was due to a fall developed terminal restriction of flexion. Those in sports could return to their sporting activities (Tegner 1–9). Cases with osteochondral fractures had occasional pain that subsided in 1 year. Mean Kujala score improved from 64.3 to 99.69 with KOOS score near normal in all. Conclusion: This new method of MPFL reconstruction gives excellent results. It avoids complications

Drug release kinetic analysis and prediction of release data via polymer molecular weight in sustained release diltiazem matrices.

Science.gov (United States)

Adibkia, K; Ghanbarzadeh, S; Mohammadi, G; Khiavi, H Z; Sabzevari, A; Barzegar-Jalali, M

2014-03-01

This study was conducted to investigate the effects of HPMC (K4M and K100M) as well as tragacanth on the drug release rate of diltiazem (DLTZ) from matrix tablets prepared by direct compression method.Mechanism of drug transport through the matrices was studied by fitting the release data to the 10 kinetic models. 3 model independent parameters; i. e., mean dissolution time (MDT), mean release rate (MRR) and release rate efficacy (RE) as well as 5 time point approaches were established to compare the dissolution profiles. To find correlation between fraction of drug released and polymer's molecular weight, dissolution data were fitted into two proposed equations.All polymers could sustain drug release up to 10 h. The release data were fitted best to Peppas and Higuchi square root kinetic models considering squared correlation coefficient and mean percent error (MPE). RE and MRR were decreased when polymer to drug ratio was increased. Conversely, t60% was increased with raising polymer /drug ratio. The fractions of drug released from the formulations prepared with tragacanth were more than those formulated using the same amount of HPMC K4M and HPMC K100M.Preparation of DLTZ matrices applying HPMCK4M, HPMC K100M and tragacanth could effectively extend the drug release. © Georg Thieme Verlag KG Stuttgart · New York.

Accelerated in-vitro release testing methods for extended-release parenteral dosage forms.

Science.gov (United States)

Shen, Jie; Burgess, Diane J

2012-07-01

This review highlights current methods and strategies for accelerated in-vitro drug release testing of extended-release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in-situ depot-forming systems and implants. Extended-release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, 'real-time' in-vitro release tests for these dosage forms are often run over a long time period. Accelerated in-vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in-vitro release methods using United States Pharmacopeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended-release parenteral dosage forms, along with the accelerated in-vitro release testing methods currently employed are discussed. Accelerated in-vitro release testing methods with good discriminatory ability are critical for quality control of extended-release parenteral products. Methods that can be used in the development of in-vitro-in-vivo correlation (IVIVC) are desirable; however, for complex parenteral products this may not always be achievable. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

Accelerated in vitro release testing methods for extended release parenteral dosage forms

Science.gov (United States)

Shen, Jie; Burgess, Diane J.

2012-01-01

Objectives This review highlights current methods and strategies for accelerated in vitro drug release testing of extended release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in situ depot-forming systems, and implants. Key findings Extended release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, “real-time” in vitro release tests for these dosage forms are often run over a long time period. Accelerated in vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in vitro release methods using United States Pharmacopoeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended release parenteral dosage forms, along with the accelerated in vitro release testing methods currently employed are discussed. Conclusions Accelerated in vitro release testing methods with good discriminatory ability are critical for quality control of extended release parenteral products. Methods that can be used in the development of in vitro-in vivo correlation (IVIVC) are desirable, however for complex parenteral products this may not always be achievable. PMID:22686344

Computed tomography imaging with the Adaptive Statistical Iterative Reconstruction (ASIR) algorithm: dependence of image quality on the blending level of reconstruction.

Science.gov (United States)

Barca, Patrizio; Giannelli, Marco; Fantacci, Maria Evelina; Caramella, Davide

2018-06-01

Computed tomography (CT) is a useful and widely employed imaging technique, which represents the largest source of population exposure to ionizing radiation in industrialized countries. Adaptive Statistical Iterative Reconstruction (ASIR) is an iterative reconstruction algorithm with the potential to allow reduction of radiation exposure while preserving diagnostic information. The aim of this phantom study was to assess the performance of ASIR, in terms of a number of image quality indices, when different reconstruction blending levels are employed. CT images of the Catphan-504 phantom were reconstructed using conventional filtered back-projection (FBP) and ASIR with reconstruction blending levels of 20, 40, 60, 80, and 100%. Noise, noise power spectrum (NPS), contrast-to-noise ratio (CNR) and modulation transfer function (MTF) were estimated for different scanning parameters and contrast objects. Noise decreased and CNR increased non-linearly up to 50 and 100%, respectively, with increasing blending level of reconstruction. Also, ASIR has proven to modify the NPS curve shape. The MTF of ASIR reconstructed images depended on tube load/contrast and decreased with increasing blending level of reconstruction. In particular, for low radiation exposure and low contrast acquisitions, ASIR showed lower performance than FBP, in terms of spatial resolution for all blending levels of reconstruction. CT image quality varies substantially with the blending level of reconstruction. ASIR has the potential to reduce noise whilst maintaining diagnostic information in low radiation exposure CT imaging. Given the opposite variation of CNR and spatial resolution with the blending level of reconstruction, it is recommended to use an optimal value of this parameter for each specific clinical application.

News/Press Releases

Data.gov (United States)

Office of Personnel Management — A press release, news release, media release, press statement is written communication directed at members of the news media for the purpose of announcing programs...

Reconstruction of convex bodies from surface tensors

DEFF Research Database (Denmark)

Kousholt, Astrid; Kiderlen, Markus

We present two algorithms for reconstruction of the shape of convex bodies in the two-dimensional Euclidean space. The first reconstruction algorithm requires knowledge of the exact surface tensors of a convex body up to rank s for some natural number s. The second algorithm uses harmonic intrinsic...... volumes which are certain values of the surface tensors and allows for noisy measurements. From a generalized version of Wirtinger's inequality, we derive stability results that are utilized to ensure consistency of both reconstruction procedures. Consistency of the reconstruction procedure based...

EIT image reconstruction with four dimensional regularization.

Science.gov (United States)

Dai, Tao; Soleimani, Manuchehr; Adler, Andy

2008-09-01

Electrical impedance tomography (EIT) reconstructs internal impedance images of the body from electrical measurements on body surface. The temporal resolution of EIT data can be very high, although the spatial resolution of the images is relatively low. Most EIT reconstruction algorithms calculate images from data frames independently, although data are actually highly correlated especially in high speed EIT systems. This paper proposes a 4-D EIT image reconstruction for functional EIT. The new approach is developed to directly use prior models of the temporal correlations among images and 3-D spatial correlations among image elements. A fast algorithm is also developed to reconstruct the regularized images. Image reconstruction is posed in terms of an augmented image and measurement vector which are concatenated from a specific number of previous and future frames. The reconstruction is then based on an augmented regularization matrix which reflects the a priori constraints on temporal and 3-D spatial correlations of image elements. A temporal factor reflecting the relative strength of the image correlation is objectively calculated from measurement data. Results show that image reconstruction models which account for inter-element correlations, in both space and time, show improved resolution and noise performance, in comparison to simpler image models.

Fully 3D GPU PET reconstruction

Energy Technology Data Exchange (ETDEWEB)

Herraiz, J.L., E-mail: joaquin@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Cal-Gonzalez, J. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Vaquero, J.J. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Desco, M. [Departmento de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Departmento Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

2011-08-21

Fully 3D iterative tomographic image reconstruction is computationally very demanding. Graphics Processing Unit (GPU) has been proposed for many years as potential accelerators in complex scientific problems, but it has not been used until the recent advances in the programmability of GPUs that the best available reconstruction codes have started to be implemented to be run on GPUs. This work presents a GPU-based fully 3D PET iterative reconstruction software. This new code may reconstruct sinogram data from several commercially available PET scanners. The most important and time-consuming parts of the code, the forward and backward projection operations, are based on an accurate model of the scanner obtained with the Monte Carlo code PeneloPET and they have been massively parallelized on the GPU. For the PET scanners considered, the GPU-based code is more than 70 times faster than a similar code running on a single core of a fast CPU, obtaining in both cases the same images. The code has been designed to be easily adapted to reconstruct sinograms from any other PET scanner, including scanner prototypes.

Fully 3D GPU PET reconstruction

International Nuclear Information System (INIS)

Herraiz, J.L.; Espana, S.; Cal-Gonzalez, J.; Vaquero, J.J.; Desco, M.; Udias, J.M.

2011-01-01

Fully 3D iterative tomographic image reconstruction is computationally very demanding. Graphics Processing Unit (GPU) has been proposed for many years as potential accelerators in complex scientific problems, but it has not been used until the recent advances in the programmability of GPUs that the best available reconstruction codes have started to be implemented to be run on GPUs. This work presents a GPU-based fully 3D PET iterative reconstruction software. This new code may reconstruct sinogram data from several commercially available PET scanners. The most important and time-consuming parts of the code, the forward and backward projection operations, are based on an accurate model of the scanner obtained with the Monte Carlo code PeneloPET and they have been massively parallelized on the GPU. For the PET scanners considered, the GPU-based code is more than 70 times faster than a similar code running on a single core of a fast CPU, obtaining in both cases the same images. The code has been designed to be easily adapted to reconstruct sinograms from any other PET scanner, including scanner prototypes.

Org.Lcsim: Event Reconstruction in Java

International Nuclear Information System (INIS)

Graf, Norman

2011-01-01

Maximizing the physics performance of detectors being designed for the International Linear Collider, while remaining sensitive to cost constraints, requires a powerful, efficient, and flexible simulation, reconstruction and analysis environment to study the capabilities of a large number of different detector designs. The preparation of Letters Of Intent for the International Linear Collider involved the detailed study of dozens of detector options, layouts and readout technologies; the final physics benchmarking studies required the reconstruction and analysis of hundreds of millions of events. We describe the Java-based software toolkit (org.lcsim) which was used for full event reconstruction and analysis. The components are fully modular and are available for tasks from digitization of tracking detector signals through to cluster finding, pattern recognition, track-fitting, calorimeter clustering, individual particle reconstruction, jet-finding, and analysis. The detector is defined by the same xml input files used for the detector response simulation, ensuring the simulation and reconstruction geometries are always commensurate by construction. We discuss the architecture as well as the performance.

Reconstruction of the midface and maxilla.

Science.gov (United States)

Dalgorf, Dustin; Higgins, Kevin

2008-08-01

To review the current classification systems and reconstructive options available for restoration of maxillectomy defects. Defects involving the midface can have a great functional and aesthetic impact on the patient. Adequate restoration of the complex three-dimensional maxillary structure is required to replace form and function of the native tissue. An in-depth discussion of appropriate recipient vessel selection and reconstructive options are included in this article. The superficial temporal vessel system is presented as a reliable anastomosis site for restoration of midfacial defects. In addition, the complications of vein grafting, arteriovenous fistula loops and alternative recipient vessels sites are addressed to manage the challenge of the vessel-depleted neck. The current indications, advantages and disadvantages of local, regional and free-flap reconstructive options available for maxillectomy defects are highlighted in order to aid the surgeon in appropriate flap selection. A myriad of reconstructive options are available to restore maxillectomy defects. The surgeon must consider each defect and the needs of the individual patient when choosing the best suited reconstructive technique.

Quality of life before reconstructive breast surgery: A preoperative comparison of patients with immediate, delayed, and major revision reconstruction.

Science.gov (United States)

Rosson, Gedge D; Shridharani, Sachin M; Magarakis, Michael; Manahan, Michele A; Basdag, Basak; Gilson, Marta M; Pusic, Andrea L

2013-05-01

Women undergo breast reconstruction at different time-points in their cancer care; knowing patients' preoperative quality of life (QoL) is critical in the overall care of the patient with breast cancer. Our objective was to describe presurgical QoL among women undergoing immediate, delayed, or major revision breast reconstructive surgery at our institution. From March 2008 to February 2009, we administered preoperative BREAST-Q questionnaires to women who presented to our institution for breast reconstruction. Univariate and multivariate analyses were performed to compare patient cohorts across multiple QoL domains including body image, physical well-being, psychosocial well-being, and sexual well-being. Of the 231 patients who presented for preoperative consultation, 176 returned the questionnaire (response rate 76%; 117 from the immediate, 21 from the delayed, and 32 from the major revision reconstruction groups, plus 6 mixed or unknown). The three groups differed significantly (P < 0.05) across four of the six domains: body image (satisfaction with breasts), psychosocial well-being, sexual well-being, and physical well-being of the chest and upper body. The immediate reconstruction group had higher (better) scores than the delayed reconstruction group, which had higher (better) scores than the major revision group. These data suggest that women presenting for breast reconstruction at different stages of reconstruction have different baseline QoL. Such data may help us better understand patient selection, education, and expectations, and may lead to improved patient-surgeon communication. Copyright © 2013 Wiley Periodicals, Inc.

Reconstruction of convex bodies from surface tensors

DEFF Research Database (Denmark)

Kousholt, Astrid; Kiderlen, Markus

2016-01-01

We present two algorithms for reconstruction of the shape of convex bodies in the two-dimensional Euclidean space. The first reconstruction algorithm requires knowledge of the exact surface tensors of a convex body up to rank s for some natural number s. When only measurements subject to noise...... of surface tensors are available for reconstruction, we recommend to use certain values of the surface tensors, namely harmonic intrinsic volumes instead of the surface tensors evaluated at the standard basis. The second algorithm we present is based on harmonic intrinsic volumes and allows for noisy...... measurements. From a generalized version of Wirtinger's inequality, we derive stability results that are utilized to ensure consistency of both reconstruction procedures. Consistency of the reconstruction procedure based on measurements subject to noise is established under certain assumptions on the noise...

Update and improvement of the global krypton-85 emission inventory

International Nuclear Information System (INIS)

Ahlswede, Jochen; Hebel, Simon; Ross, J. Ole; Schoetter, Robert; Kalinowski, Martin B.

2013-01-01

Krypton-85 is mainly produced in nuclear reactors by fission of uranium and plutonium and released during chopping and dissolution of spent fuel rods in nuclear reprocessing facilities. As noble gas it is suited as a passive tracer for evaluation of atmospheric transport models. Furthermore, research is ongoing to assess its quality as an indicator for clandestine reprocessing activities. This paper continues previous efforts to compile a comprehensive historic emission inventory for krypton-85. Reprocessing facilities are the by far largest emitters of krypton-85. Information on sources and calculations used to derive the annual krypton-85 emission is provided for all known reprocessing facilities in the world. In addition, the emission characteristics of two plants, Tokai (Japan) and La Hague (France), are analysed in detail using emission data with high temporal resolution. Other types of krypton-85 sources are power reactors, naval reactors and isotope production facilities. These sources contribute only little or negligible amounts of krypton-85 compared to the large reprocessing facilities. Taking the decay of krypton-85 into account, the global atmospheric inventory is estimated to about 5500 PBq at the end of 2009. The correctness if the inventory has been proven by meteorological simulations and its error is assumed to be in the range of a few percent. - Highlights: ► Krypton-85 is mainly produced in nuclear reactors and released during reprocessing. ► Krypten-85 can be possibly used as an indicator for clandestine reprocessing. ► This work provides an up-to-date global krypton-85 emission inventory. ► The inventory includes emissions from all possible artificial sources.

Accuracy of secondary maxillofacial reconstruction with prefabricated fibula grafts using 3D planning and guided reconstruction

NARCIS (Netherlands)

Schepers, Rutger H.; Kraeima, Joep; Vissink, Arjan; Lahoda, Lars U.; Roodenburg, Jan L. N.; Reintsema, Harry; Raghoebar, Gerry M.; Witjes, Max J.

Background: We compared the pre-operative 3D-surgical plan with the surgical outcome of complex two-stage secondary reconstruction of maxillofacial defects using inserted implants in the prefabricated fibula graft. Methods: Eleven reconstructions of maxillofacial defects with prefabricated fibulas

Orbital floor reconstruction with free flaps after maxillectomy.

Science.gov (United States)

Sampathirao, Leela Mohan C S R; Thankappan, Krishnakumar; Duraisamy, Sriprakash; Hedne, Naveen; Sharma, Mohit; Mathew, Jimmy; Iyer, Subramania

2013-06-01

Background The purpose of this study is to evaluate the outcome of orbital floor reconstruction with free flaps after maxillectomy. Methods This was a retrospective analysis of 34 consecutive patients who underwent maxillectomy with orbital floor removal for malignancies, reconstructed with free flaps. A cross-sectional survey to assess the functional and esthetic outcome was done in 28 patients who were alive and disease-free, with a minimum of 6 months of follow-up. Results Twenty-six patients had bony reconstruction, and eight had soft tissue reconstruction. Free fibula flap was the commonest flap used (n = 14). Visual acuity was normal in 86%. Eye movements were normal in 92%. Abnormal globe position resulted in nine patients. Esthetic satisfaction was good in 19 patients (68%). Though there was no statistically significant difference in outcome of visual acuity, eye movement, and patient esthetic satisfaction between patients with bony and soft tissue reconstruction, more patients without bony reconstruction had abnormal globe position (p = 0.040). Conclusion Free tissue transfer has improved the results of orbital floor reconstruction after total maxillectomy, preserving the eye. Good functional and esthetic outcome was achieved. Though our study favors a bony orbital reconstruction, a larger study with adequate power and equal distribution of patients among the groups would be needed to determine this. Free fibula flap remains the commonest choice when a bony reconstruction is contemplated.

Simultaneous maximum a posteriori longitudinal PET image reconstruction

Science.gov (United States)

Ellis, Sam; Reader, Andrew J.

2017-09-01

Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images. We achieved this by penalising voxel-wise differences between pairs of longitudinal PET images in a one-step-late maximum a posteriori (MAP) fashion, resulting in the MAP simultaneous longitudinal reconstruction (SLR) method. The proposed method reduced reconstruction errors and visually improved images relative to standard maximum likelihood expectation-maximisation (ML-EM) in simulated 2D longitudinal brain tumour scans. In reconstructions of split real 3D data with inserted simulated tumours, noise across images reconstructed with MAP-SLR was reduced to levels equivalent to doubling the number of detected counts when using ML-EM. Furthermore, quantification of tumour activities was largely preserved over a variety of longitudinal tumour changes, including changes in size and activity, with larger changes inducing larger biases relative to standard ML-EM reconstructions. Similar improvements were observed for a range of counts levels, demonstrating the robustness of the method when used with a single penalty strength. The results suggest that longitudinal regularisation is a simple but effective method of improving reconstructed PET images without using resolution degrading priors.

The PRISM3D paleoenvironmental reconstruction

Science.gov (United States)

Dowsett, H.; Robinson, M.; Haywood, A.M.; Salzmann, U.; Hill, Daniel; Sohl, L.E.; Chandler, M.; Williams, Mark; Foley, K.; Stoll, D.K.

2010-01-01

The Pliocene Research, Interpretation and Synoptic Mapping (PRISM) paleoenvironmental reconstruction is an internally consistent and comprehensive global synthesis of a past interval of relatively warm and stable climate. It is regularly used in model studies that aim to better understand Pliocene climate, to improve model performance in future climate scenarios, and to distinguish model-dependent climate effects. The PRISM reconstruction is constantly evolving in order to incorporate additional geographic sites and environmental parameters, and is continuously refined by independent research findings. The new PRISM three dimensional (3D) reconstruction differs from previous PRISM reconstructions in that it includes a subsurface ocean temperature reconstruction, integrates geochemical sea surface temperature proxies to supplement the faunal-based temperature estimates, and uses numerical models for the first time to augment fossil data. Here we describe the components of PRISM3D and describe new findings specific to the new reconstruction. Highlights of the new PRISM3D reconstruction include removal of Hudson Bay and the Great Lakes and creation of open waterways in locations where the current bedrock elevation is less than 25m above modern sea level, due to the removal of the West Antarctic Ice Sheet and the reduction of the East Antarctic Ice Sheet. The mid-Piacenzian oceans were characterized by a reduced east-west temperature gradient in the equatorial Pacific, but PRISM3D data do not imply permanent El Niño conditions. The reduced equator-to-pole temperature gradient that characterized previous PRISM reconstructions is supported by significant displacement of vegetation belts toward the poles, is extended into the Arctic Ocean, and is confirmed by multiple proxies in PRISM3D. Arctic warmth coupled with increased dryness suggests the formation of warm and salty paleo North Atlantic Deep Water (NADW) and a more vigorous thermohaline circulation system that may

Revision allograft reconstruction of the lateral collateral ligament complex in elbows with previous failed reconstruction and persistent posterolateral rotatory instability.

Science.gov (United States)

Baghdadi, Yaser M K; Morrey, Bernard F; O'Driscoll, Shawn W; Steinmann, Scott P; Sanchez-Sotelo, Joaquin

2014-07-01

Primary reconstruction of the lateral collateral ligament complex (LCLC) using graft tissue restores elbow stability in many, but not all, elbows with acute or chronic posterolateral rotatory instability (PLRI). Revision reconstruction using a tendon allograft is occasionally considered for persistent PLRI, but the outcome of revision ligament reconstruction in this setting is largely unknown. We determined whether revision allograft ligament reconstruction can (1) restore the stability and (2) result in improved elbow scores for patients with persistent PLRI of the elbow after a previous failed primary reconstructive attempt and in the context of the diverse pathology being addressed. Between 2001 and 2011, 160 surgical elbow procedures were performed at our institution for the LCLC reconstruction using allograft tissue. Only patients undergoing revision allograft reconstruction of the LCLC for persistent PLRI with a previous failed primary reconstructive attempt using graft tissue and at least I year of followup were included in the study. Eleven patients (11 elbows) fulfilled our inclusion criteria and formed our study cohort. The cohort consisted of six female patients and five male patients. The mean age at the time of revision surgery was 36 years (range, 14-59 years). The revision allograft reconstruction was carried out after a mean of 3 years (range, 2.5 months to 9 years) from a failed attempted reconstruction of the LCLC. Osseous deficiency to some extent was identified in the preoperative radiographs of eight elbows. Mean followup was 5 years (range, 1-12 years). Revision allograft reconstruction of the LCLC restored elbow stability in eight of the 11 elbows; two of the three elbows with persistent instability were operated on a third time (at 6 and 7 months after allograft revision reconstruction). For elbows with no persistent instability, the mean Mayo Elbow Performance Score at most recent followup was 83 points (range, 60-100 points), and

Structure Assisted Compressed Sensing Reconstruction of Undersampled AFM Images

DEFF Research Database (Denmark)

Oxvig, Christian Schou; Arildsen, Thomas; Larsen, Torben

2017-01-01

reconstruction algorithms that enables the use of our proposed structure model in the reconstruction process. Through a large set of reconstructions, the general reconstruction capability improvement achievable using our structured model is shown both quantitatively and qualitatively. Specifically, our...

Reconstruction of electric systems (ELE)

International Nuclear Information System (INIS)

Kohutovic, P.

2001-01-01

The original design of WWER-230 units consisted of a single common system EEPS (essential electric power supply system) per unit. The establishment of redundancy 2 x 100% EEPS was a global task. The task was started during the 'Small reconstruction' - MR V1, continued in 'Gradual reconstruction' and finished in the year 2000. (author)

Optimizing Aesthetic Outcomes in Delayed Breast Reconstruction

Directory of Open Access Journals (Sweden)

Wojciech Dec, MD

2017-08-01

Conclusions:. Optimal aesthetic results can be achieved with: (1 restoration of breast skin envelope with tissue expansion when possible, (2 optimal positioning of a small skin paddle to be later incorporated entirely into a nipple areola reconstruction when adequate breast skin surface area is present, (3 limiting the reconstructed breast mound to 2 skin tones when large area skin resurfacing is required, (4 increasing breast volume by deepithelializing, not discarding, the inferior mastectomy flap skin, (5 eccentric division of abdominal flaps when an immediate and delayed bilateral breast reconstructions are performed simultaneously; and (6 performing second-stage breast reconstruction revisions and fat grafting.

Tomographic image reconstruction using Artificial Neural Networks

International Nuclear Information System (INIS)

Paschalis, P.; Giokaris, N.D.; Karabarbounis, A.; Loudos, G.K.; Maintas, D.; Papanicolas, C.N.; Spanoudaki, V.; Tsoumpas, Ch.; Stiliaris, E.

2004-01-01

A new image reconstruction technique based on the usage of an Artificial Neural Network (ANN) is presented. The most crucial factor in designing such a reconstruction system is the network architecture and the number of the input projections needed to reconstruct the image. Although the training phase requires a large amount of input samples and a considerable CPU time, the trained network is characterized by simplicity and quick response. The performance of this ANN is tested using several image patterns. It is intended to be used together with a phantom rotating table and the γ-camera of IASA for SPECT image reconstruction

3D noise power spectrum applied on clinical MDCT scanners: effects of reconstruction algorithms and reconstruction filters

Science.gov (United States)

Miéville, Frédéric A.; Bolard, Gregory; Benkreira, Mohamed; Ayestaran, Paul; Gudinchet, François; Bochud, François; Verdun, Francis R.

2011-03-01

The noise power spectrum (NPS) is the reference metric for understanding the noise content in computed tomography (CT) images. To evaluate the noise properties of clinical multidetector (MDCT) scanners, local 2D and 3D NPSs were computed for different acquisition reconstruction parameters. A 64- and a 128-MDCT scanners were employed. Measurements were performed on a water phantom in axial and helical acquisition modes. CT dose index was identical for both installations. Influence of parameters such as the pitch, the reconstruction filter (soft, standard and bone) and the reconstruction algorithm (filtered-back projection (FBP), adaptive statistical iterative reconstruction (ASIR)) were investigated. Images were also reconstructed in the coronal plane using a reformat process. Then 2D and 3D NPS methods were computed. In axial acquisition mode, the 2D axial NPS showed an important magnitude variation as a function of the z-direction when measured at the phantom center. In helical mode, a directional dependency with lobular shape was observed while the magnitude of the NPS was kept constant. Important effects of the reconstruction filter, pitch and reconstruction algorithm were observed on 3D NPS results for both MDCTs. With ASIR, a reduction of the NPS magnitude and a shift of the NPS peak to the low frequency range were visible. 2D coronal NPS obtained from the reformat images was impacted by the interpolation when compared to 2D coronal NPS obtained from 3D measurements. The noise properties of volume measured in last generation MDCTs was studied using local 3D NPS metric. However, impact of the non-stationarity noise effect may need further investigations.

ACL Reconstruction

Science.gov (United States)

... in moderate exercise and recreational activities, or play sports that put less stress on the knees. ACL reconstruction is generally recommended if: You're an athlete and want to continue in your sport, especially if the sport involves jumping, cutting or ...

Vertex Reconstruction for AEGIS’ FACT Detector

CERN Document Server

Themistokleous, Neofytos

2017-01-01

My project dealt with the development of a vertex reconstruction technique to discriminate antihydrogen from background signals in the AEGIS apparatus. It involved the creation of a Toy Monte-Carlo to simulate particle annihilation events, and a vertex reconstruction utility based on the Bayesian theory of probability. The first results based on 107 generated events with single track in the detector are encouraging. For such events, the algorithm can reconstruct the z-coordinate accurately , while for the r-coordinate the result is less accurate.

Advanced reconstruction algorithms for electron tomography: From comparison to combination

Energy Technology Data Exchange (ETDEWEB)

Goris, B. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Roelandts, T. [Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Batenburg, K.J. [Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Centrum Wiskunde and Informatica, Science Park 123, NL-1098XG Amsterdam (Netherlands); Heidari Mezerji, H. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Bals, S., E-mail: sara.bals@ua.ac.be [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

2013-04-15

In this work, the simultaneous iterative reconstruction technique (SIRT), the total variation minimization (TVM) reconstruction technique and the discrete algebraic reconstruction technique (DART) for electron tomography are compared and the advantages and disadvantages are discussed. Furthermore, we describe how the result of a three dimensional (3D) reconstruction based on TVM can provide objective information that is needed as the input for a DART reconstruction. This approach results in a tomographic reconstruction of which the segmentation is carried out in an objective manner. - Highlights: ► A comparative study between different reconstruction algorithms for tomography is performed. ► Reconstruction algorithms that uses prior knowledge about the specimen have a superior result. ► One reconstruction algorithm can provide the prior knowledge for a second algorithm.

The reconstruction of male hair-bearing facial regions.

Science.gov (United States)

Ridgway, Emily B; Pribaz, Julian J

2011-01-01

Loss of hair-bearing regions of the face caused by trauma, tumor resection, or burn presents a difficult reconstructive task for plastic surgeons. The ideal tissue substitute should have the same characteristics as the facial area affected, consisting of thin, pliable tissue with a similar color match and hair-bearing quality. This is a retrospective study of 34 male patients who underwent reconstruction of hair-bearing facial regions performed by the senior author (J.J.P.). Local and pedicled flaps were used primarily to reconstruct defects after tumor extirpation, trauma, infections, and burns. Two patients had irradiation before reconstruction. Two patients had prior facial reconstruction with free flaps. The authors found that certain techniques of reconstructing defects in hair-bearing facial regions were more successful than others in particular facial regions and in different sizes of defects. The authors were able to develop a simple algorithm for management of facial defects involving the hair-bearing regions of the eyebrow, sideburn, beard, and mustache that may prospectively aid the planning of reconstructive strategy in these cases.

Tensor-based dictionary learning for dynamic tomographic reconstruction

International Nuclear Information System (INIS)

Tan, Shengqi; Wu, Zhifang; Zhang, Yanbo; Mou, Xuanqin; Wang, Ge; Cao, Guohua; Yu, Hengyong

2015-01-01

In dynamic computed tomography (CT) reconstruction, the data acquisition speed limits the spatio-temporal resolution. Recently, compressed sensing theory has been instrumental in improving CT reconstruction from far few-view projections. In this paper, we present an adaptive method to train a tensor-based spatio-temporal dictionary for sparse representation of an image sequence during the reconstruction process. The correlations among atoms and across phases are considered to capture the characteristics of an object. The reconstruction problem is solved by the alternating direction method of multipliers. To recover fine or sharp structures such as edges, the nonlocal total variation is incorporated into the algorithmic framework. Preclinical examples including a sheep lung perfusion study and a dynamic mouse cardiac imaging demonstrate that the proposed approach outperforms the vectorized dictionary-based CT reconstruction in the case of few-view reconstruction. (paper)

Tensor-based Dictionary Learning for Dynamic Tomographic Reconstruction

Science.gov (United States)

Tan, Shengqi; Zhang, Yanbo; Wang, Ge; Mou, Xuanqin; Cao, Guohua; Wu, Zhifang; Yu, Hengyong

2015-01-01

In dynamic computed tomography (CT) reconstruction, the data acquisition speed limits the spatio-temporal resolution. Recently, compressed sensing theory has been instrumental in improving CT reconstruction from far few-view projections. In this paper, we present an adaptive method to train a tensor-based spatio-temporal dictionary for sparse representation of an image sequence during the reconstruction process. The correlations among atoms and across phases are considered to capture the characteristics of an object. The reconstruction problem is solved by the alternating direction method of multipliers. To recover fine or sharp structures such as edges, the nonlocal total variation is incorporated into the algorithmic framework. Preclinical examples including a sheep lung perfusion study and a dynamic mouse cardiac imaging demonstrate that the proposed approach outperforms the vectorized dictionary-based CT reconstruction in the case of few-view reconstruction. PMID:25779991

Shredded banknotes reconstruction using AKAZE points.

Science.gov (United States)

Nabiyev, Vasif V; Yılmaz, Seçkin; Günay, Asuman; Muzaffer, Gül; Ulutaş, Güzin

2017-09-01

Shredded banknote reconstruction is a recent topic and can be viewed as solving large-scale jigsaw puzzles. Also, problems such as reconstruction of fragmented documents, photographs and historical artefacts are closely related with this topic. The high computational complexity of these problems increases the need for the development of new methods Reconstruction of shredded banknotes consists of three main stages. (1) Matching fragments with a reference banknote. (2) Aligning the fragments by rotating at certain angles. (3) Assembling the fragments. The existing methods can successfully applied to synthetic banknote fragments which are created in computer environment. But when real banknote reconstruction problem is considered, different sub problems arise and make the existing methods inadequate. In this study, a keypoint based method, named AKAZE, was used to make the matching process effective. This is the first study that uses the AKAZE method in the reconstruction of shredded banknotes. A new method for fragment alignment has also been proposed. In this method, the convex hulls that contain all true matched AKAZE keypoints were found on reference banknote and fragments. The orientations of fragments were estimated accurately by comparing these convex polygons. Also, a new criterion was developed to reveal the success rates of reconstructed banknotes. In addition, two different data sets including real and synthetic banknote fragments of different countries were created to test the success of proposed method. Copyright © 2017 Elsevier B.V. All rights reserved.

The Economics of Prepectoral Breast Reconstruction.

Science.gov (United States)

Glasberg, Scot Bradley

2017-12-01

The world of breast reconstruction over the last several years has seen a dramatic shift in focus to discussion and the application of placing tissue expanders and implants back into the prepectoral space. Although this technique failed during the early advent of breast reconstruction, newer technologies such as advances in fat grafting, improved acellular dermal matrices, better methods of assessing breast flap viability, and enhanced implants appear to have set the stage for the resurgence and positive early results seen with this technique. The main benefits of a switch to prepectoral breast reconstruction clinically appears to be less associated pain, lower incidence of animation deformities, and its associated symptoms as well as presumably better aesthetics. Early data suggest that the results are extremely promising and early adopters have attempted to define the ideal patients for prepectoral breast reconstruction. As with any new operative procedure, an assessment of finances and costs are crucial to its successful implementation. Although current data are minimal, this article attempts to build the fundamentals of an economic model that exhibits and displays potential savings through the use of prepectoral breast reconstruction.

Baryon Acoustic Oscillations reconstruction with pixels

Energy Technology Data Exchange (ETDEWEB)

Obuljen, Andrej [SISSA—International School for Advanced Studies, Via Bonomea 265, 34136 Trieste (Italy); Villaescusa-Navarro, Francisco [Center for Computational Astrophysics, 160 5th Ave, New York, NY, 10010 (United States); Castorina, Emanuele [Berkeley Center for Cosmological Physics, University of California, Berkeley, CA 94720 (United States); Viel, Matteo, E-mail: aobuljen@sissa.it, E-mail: fvillaescusa@simonsfoundation.org, E-mail: ecastorina@berkeley.edu, E-mail: viel@oats.inaf.it [INAF, Osservatorio Astronomico di Trieste, via Tiepolo 11, I-34131 Trieste (Italy)

2017-09-01

Gravitational non-linear evolution induces a shift in the position of the baryon acoustic oscillations (BAO) peak together with a damping and broadening of its shape that bias and degrades the accuracy with which the position of the peak can be determined. BAO reconstruction is a technique developed to undo part of the effect of non-linearities. We present and analyse a reconstruction method that consists of displacing pixels instead of galaxies and whose implementation is easier than the standard reconstruction method. We show that this method is equivalent to the standard reconstruction technique in the limit where the number of pixels becomes very large. This method is particularly useful in surveys where individual galaxies are not resolved, as in 21cm intensity mapping observations. We validate this method by reconstructing mock pixelated maps, that we build from the distribution of matter and halos in real- and redshift-space, from a large set of numerical simulations. We find that this method is able to decrease the uncertainty in the BAO peak position by 30-50% over the typical angular resolution scales of 21 cm intensity mapping experiments.

Patient-specific reconstruction plates are the missing link in computer-assisted mandibular reconstruction: A showcase for technical description.

Science.gov (United States)

Cornelius, Carl-Peter; Smolka, Wenko; Giessler, Goetz A; Wilde, Frank; Probst, Florian A

2015-06-01

Preoperative planning of mandibular reconstruction has moved from mechanical simulation by dental model casts or stereolithographic models into an almost completely virtual environment. CAD/CAM applications allow a high level of accuracy by providing a custom template-assisted contouring approach for bone flaps. However, the clinical accuracy of CAD reconstruction is limited by the use of prebent reconstruction plates, an analogue step in an otherwise digital workstream. In this paper the integration of computerized, numerically-controlled (CNC) milled, patient-specific mandibular plates (PSMP) within the virtual workflow of computer-assisted mandibular free fibula flap reconstruction is illustrated in a clinical case. Intraoperatively, the bone segments as well as the plate arms showed a very good fit. Postoperative CT imaging demonstrated close approximation of the PSMP and fibular segments, and good alignment of native mandible and fibular segments and intersegmentally. Over a follow-up period of 12 months, there was an uneventful course of healing with good bony consolidation. The virtual design and automated fabrication of patient-specific mandibular reconstruction plates provide the missing link in the virtual workflow of computer-assisted mandibular free fibula flap reconstruction. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Simulated annealing image reconstruction for positron emission tomography

International Nuclear Information System (INIS)

Sundermann, E.; Lemahieu, I.; Desmedt, P.

1994-01-01

In Positron Emission Tomography (PET) images have to be reconstructed from moisy projection data. The noise on the PET data can be modeled by a Poison distribution. In this paper, we present the results of using the simulated annealing technique to reconstruct PET images. Various parameter settings of the simulated annealing algorithm are discussed and optimized. The reconstructed images are of good quality and high contrast, in comparison to other reconstruction techniques. (authors)

Hydraulic running and release tool with mechanical emergency release

International Nuclear Information System (INIS)

Baker, S.F.

1991-01-01

This patent describes a setting tool for connection in a well string to position a tubular member in a well bore. It comprises: a mandrel adapted to be connected to the well string; an outer sleeve surrounding the mandrel and releasably secured thereto; a latch nut releasably connected to the outer sleeve; piston means sealingly engaging the mandrel; shear means releasably securing the piston to the latch nut to maintain the latch nut releasably connected to the tubular member; the mandrel having port means for conducting fluid pressure from the well string to release the piston means from and the latch nut; cooperating engageable surfaces on the piston and latch nut to reengage them together after the piston moves a predetermined longitudinal distance relative to the latch nut; and additional cooperating engageable surfaces on the latch nut and the outer sleeve which are engageable when the piston and engaged latch nut are moved a predetermined additional longitudinal distance by fluid pressure to secure the engaged piston and latch nut with the outer sleeve for retrieval along with the mandrel from the well bore

Mandibular reconstruction in adults: a review.

NARCIS (Netherlands)

Goh, B.T.; Lee, S.; Tideman, H.; Stoelinga, P.J.W.

2008-01-01

Mandibular defects may result from trauma, inflammatory disease and benign or malignant tumours. Mastication, speech and facial aesthetics are often severely compromised without reconstruction. The goal of mandibular reconstruction is to restore facial form and function, implying repair of

Innovations in diabetic foot reconstruction using supermicrosurgery.

Science.gov (United States)

Suh, Hyun Suk; Oh, Tae Suk; Hong, Joon Pio

2016-01-01

The treatment of diabetic foot ulceration is complex with multiple factors involved, and it may often lead to limb amputation. Hence, a multidisciplinary approach is warranted to cover the spectrum of treatment for diabetic foot, but in complex wounds, surgical treatment is inevitable. Surgery may involve the decision to preserve the limb by reconstruction or to amputate it. Reconstruction involves preserving the limb with secure coverage. Local flaps usually are able to provide sufficient coverage for small or moderate sized wound, but for larger wounds, soft tissue coverage involves flaps that are distantly located from the wound. Reconstruction of distant flap usually involves microsurgery, and now, further innovative methods such as supermicrosurgery have further given complex wounds a better chance to be reconstructed and limbs salvaged. This article reviews the microsurgery involved in reconstruction and introduces the new method of supermicrosurgery. Copyright © 2016 John Wiley & Sons, Ltd.

Church, mission and reconstruction: Being a church with integrity in reconstruction discourse in post-colonial Zimbabwe

Directory of Open Access Journals (Sweden)

Canon B. Shambare

2018-05-01

Full Text Available The church in Africa, like its counterparts elsewhere in the world, is called to fulfil the mission of God as expressed in the call ‘Missio Dei’ and influentially remains with the integrity of the mission of Christ (Missio Christos, which is liberative and practical. For Christ was not only concerned with the spiritual needs of the people, but also with their material well-being. The following question therefore arises: how can the church in Africa, in general, and in Zimbabwe, in particular, actively do God’s mission and remain with integrity in the midst of the reality of suffering. Furthermore, how can the church for mission and reconstruction be understood in a post-colonial Zimbabwe given the contextual realities of political crises, corruption, poverty, moral decadence, defined or censored truth, leadership crises and no freedom of expression? This article argues that, although the church is faced with these arduous realities, it remains called by God to do God’s mission. While in post-colonial Zimbabwe the socio-political, socio-economic and socio-religious situation might seem hopeless, the church has remained vibrant and alive for reconstruction theology. The transformation of society is possible given the authority and mission mandate of the church. This article argues that the church is a key player in reconstruction theology and in the transformation of society. For transformation to be possible, the church should witness to the gospel of Christ without fear of being labelled, castrated and persecuted. The article asserts that the spirit of the Bible should be revived in a time of reconstruction in Zimbabwe. The assumption in this article is that Zimbabwe is ready for reconstruction discourse. For this to happen, the researchers argue that the church as a critical relevant player in reconstruction needs to ‘be church’ in its missional mandates. Integrity is essential if a church wants to be relevantly missional and

Automatic reconstruction of fault networks from seismicity catalogs including location uncertainty

International Nuclear Information System (INIS)

Wang, Y.

2013-01-01

Within the framework of plate tectonics, the deformation that arises from the relative movement of two plates occurs across discontinuities in the earth's crust, known as fault zones. Active fault zones are the causal locations of most earthquakes, which suddenly release tectonic stresses within a very short time. In return, fault zones slowly grow by accumulating slip due to such earthquakes by cumulated damage at their tips, and by branching or linking between pre-existing faults of various sizes. Over the last decades, a large amount of knowledge has been acquired concerning the overall phenomenology and mechanics of individual faults and earthquakes: A deep physical and mechanical understanding of the links and interactions between and among them is still missing, however. One of the main issues lies in our failure to always succeed in assigning an earthquake to its causative fault. Using approaches based in pattern-recognition theory, more insight into the relationship between earthquakes and fault structure can be gained by developing an automatic fault network reconstruction approach using high resolution earthquake data sets at largely different scales and by considering individual event uncertainties. This thesis introduces the Anisotropic Clustering of Location Uncertainty Distributions (ACLUD) method to reconstruct active fault networks on the basis of both earthquake locations and their estimated individual uncertainties. This method consists in fitting a given set of hypocenters with an increasing amount of finite planes until the residuals of the fit compare with location uncertainties. After a massive search through the large solution space of possible reconstructed fault networks, six different validation procedures are applied in order to select the corresponding best fault network. Two of the validation steps (cross-validation and Bayesian Information Criterion (BIC)) process the fit residuals, while the four others look for solutions that

Automatic reconstruction of fault networks from seismicity catalogs including location uncertainty

Energy Technology Data Exchange (ETDEWEB)

Wang, Y.

2013-07-01

Within the framework of plate tectonics, the deformation that arises from the relative movement of two plates occurs across discontinuities in the earth's crust, known as fault zones. Active fault zones are the causal locations of most earthquakes, which suddenly release tectonic stresses within a very short time. In return, fault zones slowly grow by accumulating slip due to such earthquakes by cumulated damage at their tips, and by branching or linking between pre-existing faults of various sizes. Over the last decades, a large amount of knowledge has been acquired concerning the overall phenomenology and mechanics of individual faults and earthquakes: A deep physical and mechanical understanding of the links and interactions between and among them is still missing, however. One of the main issues lies in our failure to always succeed in assigning an earthquake to its causative fault. Using approaches based in pattern-recognition theory, more insight into the relationship between earthquakes and fault structure can be gained by developing an automatic fault network reconstruction approach using high resolution earthquake data sets at largely different scales and by considering individual event uncertainties. This thesis introduces the Anisotropic Clustering of Location Uncertainty Distributions (ACLUD) method to reconstruct active fault networks on the basis of both earthquake locations and their estimated individual uncertainties. This method consists in fitting a given set of hypocenters with an increasing amount of finite planes until the residuals of the fit compare with location uncertainties. After a massive search through the large solution space of possible reconstructed fault networks, six different validation procedures are applied in order to select the corresponding best fault network. Two of the validation steps (cross-validation and Bayesian Information Criterion (BIC)) process the fit residuals, while the four others look for solutions that

HEEL BONE RECONSTRUCTIVE OSTEOSYNTHESIS

Directory of Open Access Journals (Sweden)

A. N. Svetashov

2010-01-01

Full Text Available To detect the most appropriate to heel bone injury severity variants of reconstructive osteosynthesis it was analyzed treatment results of 56 patients. In 15 (26.8% patients classic methods of surgical service were applied, in 41 (73.2% cases to restore the defect porous implants were used. Osteosynthesis without heel bone plastic restoration accomplishment was ineffective in 60% patients from control group. Reconstructive osteosynthesis method ensures long-term good functional effect of rehabilitation in 96.4% patients from the basic group.

Vertex reconstruction in CMS

International Nuclear Information System (INIS)

Chabanat, E.; D'Hondt, J.; Estre, N.; Fruehwirth, R.; Prokofiev, K.; Speer, T.; Vanlaer, P.; Waltenberger, W.

2005-01-01

Due to the high track multiplicity in the final states expected in proton collisions at the LHC experiments, novel vertex reconstruction algorithms are required. The vertex reconstruction problem can be decomposed into a pattern recognition problem ('vertex finding') and an estimation problem ('vertex fitting'). Starting from least-squares methods, robustifications of the classical algorithms are discussed and the statistical properties of the novel methods are shown. A whole set of different approaches for the vertex finding problem is presented and compared in relevant physics channels

Simulated annealing image reconstruction for positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Sundermann, E; Lemahieu, I; Desmedt, P [Department of Electronics and Information Systems, University of Ghent, St. Pietersnieuwstraat 41, B-9000 Ghent, Belgium (Belgium)

1994-12-31

In Positron Emission Tomography (PET) images have to be reconstructed from moisy projection data. The noise on the PET data can be modeled by a Poison distribution. In this paper, we present the results of using the simulated annealing technique to reconstruct PET images. Various parameter settings of the simulated annealing algorithm are discussed and optimized. The reconstructed images are of good quality and high contrast, in comparison to other reconstruction techniques. (authors). 11 refs., 2 figs.

DART: a practical reconstruction algorithm for discrete tomography.

Science.gov (United States)

Batenburg, Kees Joost; Sijbers, Jan

2011-09-01

In this paper, we present an iterative reconstruction algorithm for discrete tomography, called discrete algebraic reconstruction technique (DART). DART can be applied if the scanned object is known to consist of only a few different compositions, each corresponding to a constant gray value in the reconstruction. Prior knowledge of the gray values for each of the compositions is exploited to steer the current reconstruction towards a reconstruction that contains only these gray values. Based on experiments with both simulated CT data and experimental μCT data, it is shown that DART is capable of computing more accurate reconstructions from a small number of projection images, or from a small angular range, than alternative methods. It is also shown that DART can deal effectively with noisy projection data and that the algorithm is robust with respect to errors in the estimation of the gray values.

Track Simulation and Reconstruction in the ATLAS experiment

CERN Document Server

Salzburger, Andreas; Elsing, Markus

The reconstruction and simulation of particle trajectories is an inevitable part of the analysis strate- gies for data taken with the ATLAS detector. Many aspects and necessary parts of a high-quality track reconstruction will be presented and discussed in this work. At first, the technical realisation of the data model and the reconstruction geometry will be given; the reconstruction geometry is charac- terised by a newly developed navigation model and an automated procedure for the synchronisation of the detailed simulation geometry description with the simplified reconstruction geometry model, which allows a precise description of the tracker material in track reconstruction. Both components help the coherent and fast integration of material effects in a newly established track extrapolation package, that is discussed in the following. The extrapolation engine enables a highly precise trans- port of the track parameterisation and the associated covariances through the complex magnetic field and the detec...

Reconstruction of a ring applicator using CT imaging: impact of the reconstruction method and applicator orientation

DEFF Research Database (Denmark)

Hellebust, Taran Paulsen; Tanderup, Kari; Bergstrand, Eva Stabell

2007-01-01

in multiplanar reconstructed images (MPR) and (3) library plans, using pre-defined applicator geometry (LIB). The doses to the lead pellets were calculated. The relative standard deviation (SD) for all reconstruction methods was less than 3.7% in the dose points. The relative SD for the LIB method...

Summary of literature review of risk communication: Hanford Environmental Dose Reconstruction Project

International Nuclear Information System (INIS)

Byram, S.J.

1991-05-01

The Hanford Environmental Dose Reconstruction (HEDR) Project will estimate radiation exposures people may have received from radioactive materials released during past operations at the Department of Energy's Hanford Site near Richland, Washington. The project is being conducted by Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The Centers for Disease Control (CDC) will use HEDR dose estimates in studies to investigate a potential link between thyroid disease and historical Hanford emissions. The HEDR Project was initiated to address public concerns about the possible health impacts from past releases of radioactive materials from Hanford. The TSP recognized early in the project that special mechanisms would be required to communicate effectively to the many different concerned audiences. To identify and develop these mechanisms, the TSP issued Directive 89-7 to PNL in May 1989. The TSP directed PNL to examine methods to communicate the causes and effects of uncertainties in the dose estimates. A literature review was conducted as the first activity in response to the TSP's directive. This report presents the results of the literature review. The objective of the literature review was to identify ''key principles'' that could be applied to develop communications strategies for the project. 26 refs., 6 figs

Large scientific releases

International Nuclear Information System (INIS)

Pongratz, M.B.

1981-01-01

The motivation for active experiments in space is considered, taking into account the use of active techniques to obtain a better understanding of the natural space environment, the utilization of the advantages of space as a laboratory to study fundamental plasma physics, and the employment of active techniques to determine the magnitude, degree, and consequences of artificial modification of the space environment. It is pointed out that mass-injection experiments in space plasmas began about twenty years ago with the Project Firefly releases. Attention is given to mass-release techniques and diagnostics, operational aspects of mass release active experiments, the active observation of mass release experiments, active perturbation mass release experiments, simulating an artificial modification of the space environment, and active experiments to study fundamental plasma physics

SUBSTANTIATION OF SOLUTIONS PERTAINING TO COMPLEX PRODUCTION RECONSTRUCTION

Directory of Open Access Journals (Sweden)

V. Y. Gurinovich

2011-01-01

Full Text Available While taking an example of reconstruction and modernization of OJSC «Construction and Mounting Trust No.16, Novopolotsk» the paper substantiates solutions for complex production reconstruction. The production reconstruction is divided in three start-up facilities ensuring continuous finished-product output.

Iterative concurrent reconstruction algorithms for emission computed tomography

International Nuclear Information System (INIS)

Brown, J.K.; Hasegawa, B.H.; Lang, T.F.

1994-01-01

Direct reconstruction techniques, such as those based on filtered backprojection, are typically used for emission computed tomography (ECT), even though it has been argued that iterative reconstruction methods may produce better clinical images. The major disadvantage of iterative reconstruction algorithms, and a significant reason for their lack of clinical acceptance, is their computational burden. We outline a new class of ''concurrent'' iterative reconstruction techniques for ECT in which the reconstruction process is reorganized such that a significant fraction of the computational processing occurs concurrently with the acquisition of ECT projection data. These new algorithms use the 10-30 min required for acquisition of a typical SPECT scan to iteratively process the available projection data, significantly reducing the requirements for post-acquisition processing. These algorithms are tested on SPECT projection data from a Hoffman brain phantom acquired with a 2 x 10 5 counts in 64 views each having 64 projections. The SPECT images are reconstructed as 64 x 64 tomograms, starting with six angular views. Other angular views are added to the reconstruction process sequentially, in a manner that reflects their availability for a typical acquisition protocol. The results suggest that if T s of concurrent processing are used, the reconstruction processing time required after completion of the data acquisition can be reduced by at least 1/3 T s. (Author)

Stimulatory effects of neuronally released norepinephrine on renin release in vitro

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Yasuo; Kawazoe, Shinka; Ichihara, Toshio; Shinyama, Hiroshi; Kageyama, Masaaki; Morimoto, Shiro (Osaka Univ. of Pharmaceutical Sciences (Japan))

1988-10-01

Extracellular high potassium inhibits renin release in vitro by increasing calcium concentrations in the juxtaglomerular cells. The authors found that the decreased response of renin release from rat kidney cortical slices in high potassium solution changed to a strikingly increased one in the presence of nifedipine at doses over 10{sup {minus}6} M. They then examined the stimulatory effect of extracellular high potassium in the presence of nifedipine on renin release. The enhancement of release was significantly suppressed either by propranolol or by metoprolol but not by prazosin. High potassium plus nifedipine-induced increase in renin release was markedly attenuated by renal denervation. The enhancing effect was not observed when the slices were incubated in calcium-free medium. Divalent cations such as Cd{sup 2+}, Co{sup 2+}, and Mn{sup 2+} blocked this enhancement in a concentration-dependent manner. High potassium elicited an increase in {sup 3}H efflux from the slices preloaded with ({sup 3}H)-norepinephrine. The increasing effect was not influenced by nifedipine but was abolished by the removal of extracellular calcium or by the addition of divalent cations. These observations suggest to us that the high potassium plus nifedipine-induced increase in renin release from the slices is mediated by norepinephrine derived from renal sympathetic nerves and that this neuronally released norepinephrine stimulates renin release via activation of {beta}-adrenoceptors.

Weight Multispectral Reconstruction Strategy for Enhanced Reconstruction Accuracy and Stability With Cerenkov Luminescence Tomography.

Science.gov (United States)

Hongbo Guo; Xiaowei He; Muhan Liu; Zeyu Zhang; Zhenhua Hu; Jie Tian

2017-06-01

Cerenkov luminescence tomography (CLT) provides a novel technique for 3-D noninvasive detection of radiopharmaceuticals in living subjects. However, because of the severe scattering of Cerenkov light, the reconstruction accuracy and stability of CLT is still unsatisfied. In this paper, a modified weight multispectral CLT (wmCLT) reconstruction strategy was developed which split the Cerenkov radiation spectrum into several sub-spectral bands and weighted the sub-spectral results to obtain the final result. To better evaluate the property of the wmCLT reconstruction strategy in terms of accuracy, stability and practicability, several numerical simulation experiments and in vivo experiments were conducted and the results obtained were compared with the traditional multispectral CLT (mCLT) and hybrid-spectral CLT (hCLT) reconstruction strategies. The numerical simulation results indicated that wmCLT strategy significantly improved the accuracy of Cerenkov source localization and intensity quantitation and exhibited good stability in suppressing noise in numerical simulation experiments. And the comparison of the results achieved from different in vivo experiments further indicated significant improvement of the wmCLT strategy in terms of the shape recovery of the bladder and the spatial resolution of imaging xenograft tumors. Overall the strategy reported here will facilitate the development of nuclear and optical molecular tomography in theoretical study.

Rates of Reconstruction Failure in Patients Undergoing Immediate Reconstruction With Tissue Expanders and/or Implants and Postmastectomy Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Fowble, Barbara, E-mail: BFowble@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, San Francisco, California (United States); Park, Catherine [Department of Radiation Oncology, University of California San Francisco, San Francisco, California (United States); Wang, Frederick; Peled, Anne [Division of Plastic and Reconstructive Surgery, University of California San Francisco, San Francisco, California (United States); Alvarado, Michael; Ewing, Cheryl; Esserman, Laura [Carol Franc Buck Breast Care Center, Department of Surgery, University of California San Francisco, San Francisco, California (United States); Foster, Robert; Sbitany, Hani [Division of Plastic and Reconstructive Surgery, University of California San Francisco, San Francisco, California (United States); Hanlon, Alex [University of Pennsylvania School of Nursing, Philadelphia, Pennsylvania (United States)

2015-07-01

Objectives: Mastectomy rates for breast cancer have increased, with a parallel increase in immediate reconstruction. For some women, tissue expander and implant (TE/I) reconstruction is the preferred or sole option. This retrospective study examined the rate of TE/I reconstruction failure (ie, removal of the TE or I with the inability to replace it resulting in no final reconstruction or autologous tissue reconstruction) in patients receiving postmastectomy radiation therapy (PMRT). Methods and Materials: Between 2004 and 2012, 99 women had skin-sparing mastectomies (SSM) or total nipple/areolar skin-sparing mastectomies (TSSM) with immediate TE/I reconstruction and PMRT for pathologic stage II to III breast cancer. Ninety-seven percent had chemotherapy (doxorubicin and taxane-based), 22% underwent targeted therapies, and 78% had endocrine therapy. Radiation consisted of 5000 cGy given in 180 to 200 cGy to the reconstructed breast with or without treatment to the supraclavicular nodes. Median follow-up was 3.8 years. Results: Total TE/I failure was 18% (12% without final reconstruction, 6% converted to autologous reconstruction). In univariate analysis, the strongest predictor of reconstruction failure (RF) was absence of total TE/I coverage (acellular dermal matrix and/or serratus muscle) at the time of radiation. RF occurred in 32.5% of patients without total coverage compared to 9% with coverage (P=.0069). For women with total coverage, the location of the mastectomy scar in the inframammary fold region was associated with higher RF (19% vs 0%, P=.0189). In multivariate analysis, weight was a significant factor for RF, with lower weight associated with a higher RF. Weight appeared to be a surrogate for the interaction of total coverage, thin skin flaps, interval to exchange, and location of the mastectomy scar. Conclusions: RFs in patients receiving PMRT were lowered with total TE/I coverage at the time of radiation by avoiding inframammary fold incisions and

Final results of the gradual reconstruction of Bohunice VI in Slovakia and evaluation of the reconstruction by international missions

International Nuclear Information System (INIS)

Ferenc, M.

2001-01-01

The gradual reconstruction of the Bohunice V1 nuclear power plant (Slovakia) represents the most extensive reconstruction of a nuclear power plant in operation as implemented worldwide up to now. Extensive reconstruction works in both civil construction and process parts, in instrumentation and control part, and in electric part enhanced both nuclear safety and operational reliability of Bohunice V1 in a significant way.(author)

Track reconstruction in CMS high luminosity environment

CERN Document Server

AUTHOR|(CDS)2067159

2016-01-01

The CMS tracker is the largest silicon detector ever built, covering 200 square meters and providing an average of 14 high-precision measurements per track. Tracking is essential for the reconstruction of objects like jets, muons, electrons and tau leptons starting from the raw data from the silicon pixel and strip detectors. Track reconstruction is widely used also at trigger level as it improves objects tagging and resolution.The CMS tracking code is organized in several levels, known as iterative steps, each optimized to reconstruct a class of particle trajectories, as the ones of particles originating from the primary vertex or displaced tracks from particles resulting from secondary vertices. Each iterative step consists of seeding, pattern recognition and fitting by a kalman filter, and a final filtering and cleaning. Each subsequent step works on hits not yet associated to a reconstructed particle trajectory.The CMS tracking code is continuously evolving to make the reconstruction computing load compat...

Track reconstruction in CMS high luminosity environment

CERN Document Server

Goetzmann, Christophe

2014-01-01

The CMS tracker is the largest silicon detector ever built, covering 200 square meters and providing an average of 14 high-precision measurements per track. Tracking is essential for the reconstruction of objects like jets, muons, electrons and tau leptons starting from the raw data from the silicon pixel and strip detectors. Track reconstruction is widely used also at trigger level as it improves objects tagging and resolution.The CMS tracking code is organized in several levels, known as iterative steps, each optimized to reconstruct a class of particle trajectories, as the ones of particles originating from the primary vertex or displaced tracks from particles resulting from secondary vertices. Each iterative step consists of seeding, pattern recognition and fitting by a kalman filter, and a final filtering and cleaning. Each subsequent step works on hits not yet associated to a reconstructed particle trajectory.The CMS tracking code is continuously evolving to make the reconstruction computing load compat...

Current Strategies in Reconstruction of Maxillectomy Defects

Science.gov (United States)

Andrades, Patricio; Militsakh, Oleg; Hanasono, Matthew M.; Rieger, Jana; Rosenthal, Eben L.

2014-01-01

Objective To outline a contemporary review of defect classification and reconstructive options. Design Review article. Setting Tertiary care referral centers. Results Although prosthetic rehabilitation remains the standard of care in many institutions, the discomfort of wearing, removing, and cleaning a prosthesis; the inability to retain a prosthesis in large defects; and the frequent need for readjustments often limit the value of this cost-effective and successful method of restoring speech and mastication. However, flap reconstruction offers an option for many, although there is no agreement as to which techniques should be used for optimal reconstruction. Flap reconstruction also involves a longer recovery time with increased risk of surgical complications, has higher costs associated with the procedure, and requires access to a highly experienced surgeon. Conclusion The surgeon and reconstructive team must make individualized decisions based on the extent of the maxillectomy defect (eg, the resection of the infraorbital rim, the extent of palate excision, skin compromise) and the need for radiation therapy. PMID:21844415

Reconstructing baryon oscillations: A Lagrangian theory perspective

International Nuclear Information System (INIS)

Padmanabhan, Nikhil; White, Martin; Cohn, J. D.

2009-01-01

Recently Eisenstein and collaborators introduced a method to 'reconstruct' the linear power spectrum from a nonlinearly evolved galaxy distribution in order to improve precision in measurements of baryon acoustic oscillations. We reformulate this method within the Lagrangian picture of structure formation, to better understand what such a method does, and what the resulting power spectra are. We show that reconstruction does not reproduce the linear density field, at second order. We however show that it does reduce the damping of the oscillations due to nonlinear structure formation, explaining the improvements seen in simulations. Our results suggest that the reconstructed power spectrum is potentially better modeled as the sum of three different power spectra, each dominating over different wavelength ranges and with different nonlinear damping terms. Finally, we also show that reconstruction reduces the mode-coupling term in the power spectrum, explaining why miscalibrations of the acoustic scale are reduced when one considers the reconstructed power spectrum.

Primary Vertex Reconstruction at the ATLAS Experiment

CERN Document Server

Grimm, Kathryn; The ATLAS collaboration

2016-01-01

Efficient and precise reconstruction of the primary vertex in an LHC collision is essential in both the reconstruction of the full kinematic properties of a hard-scatter event and of soft interactions as a measure of the amount of pile-up. The reconstruction of primary vertices in the busy, high pile-up environment of Run-2 of the LHC is a challenging task. New methods have been developed by the ATLAS experiment to reconstruct vertices in such environments. Advances in vertex seeding include methods taken from medical imaging, which allow for reconstruction of multiple vertices with small spatial separation. The adoption of this new seeding algorithm within the ATLAS adaptive vertex finding and fitting procedure will be discussed, and the first results of the new techniques from Run-2 data will be presented. Additionally, data-driven methods to evaluate vertex resolution will be presented with special focus on correct methods to evaluate the effect of the beam spot constraint; results from these methods in Ru...

Model-Based Reconstructive Elasticity Imaging Using Ultrasound

Directory of Open Access Journals (Sweden)

Salavat R. Aglyamov

2007-01-01

Full Text Available Elasticity imaging is a reconstructive imaging technique where tissue motion in response to mechanical excitation is measured using modern imaging systems, and the estimated displacements are then used to reconstruct the spatial distribution of Young's modulus. Here we present an ultrasound elasticity imaging method that utilizes the model-based technique for Young's modulus reconstruction. Based on the geometry of the imaged object, only one axial component of the strain tensor is used. The numerical implementation of the method is highly efficient because the reconstruction is based on an analytic solution of the forward elastic problem. The model-based approach is illustrated using two potential clinical applications: differentiation of liver hemangioma and staging of deep venous thrombosis. Overall, these studies demonstrate that model-based reconstructive elasticity imaging can be used in applications where the geometry of the object and the surrounding tissue is somewhat known and certain assumptions about the pathology can be made.

Comparison Between the Spectrum reconstruction methodology and release transmitted by both based in pictures taken EPID; Comparacion entre la metodologia de recostruccion de espectros por transmision y por disperison, ambas basadas en imagenes tomadas con EPID

Energy Technology Data Exchange (ETDEWEB)

Juste, B.; Miro, R.; Jambrina, A.; Campayo, J. M.; Diez, S.; Santos, A.; Verdu, V.

2013-07-01

A comparison of the spectral reconstruction based on data transmission and spectral reconstruction based on scattering data is presented, we have both developed using EPID images. It is shown that the reconstruction results based on transmission offer much better fit with the theoretical predictions.

Outcome of different facial nerve reconstruction techniques

OpenAIRE

Mohamed, Aboshanif; Omi, Eigo; Honda, Kohei; Suzuki, Shinsuke; Ishikawa, Kazuo

2016-01-01

Abstract Introduction: There is no technique of facial nerve reconstruction that guarantees facial function recovery up to grade III. Objective: To evaluate the efficacy and safety of different facial nerve reconstruction techniques. Methods: Facial nerve reconstruction was performed in 22 patients (facial nerve interpositional graft in 11 patients and hypoglossal-facial nerve transfer in another 11 patients). All patients had facial function House-Brackmann (HB) grade VI, either caused by...

An Intelligent Actuator Fault Reconstruction Scheme for Robotic Manipulators.

Science.gov (United States)

Xiao, Bing; Yin, Shen

2018-02-01

This paper investigates a difficult problem of reconstructing actuator faults for robotic manipulators. An intelligent approach with fast reconstruction property is developed. This is achieved by using observer technique. This scheme is capable of precisely reconstructing the actual actuator fault. It is shown by Lyapunov stability analysis that the reconstruction error can converge to zero after finite time. A perfect reconstruction performance including precise and fast properties can be provided for actuator fault. The most important feature of the scheme is that, it does not depend on control law, dynamic model of actuator, faults' type, and also their time-profile. This super reconstruction performance and capability of the proposed approach are further validated by simulation and experimental results.

Multicore Performance of Block Algebraic Iterative Reconstruction Methods

DEFF Research Database (Denmark)

Sørensen, Hans Henrik B.; Hansen, Per Christian

2014-01-01

Algebraic iterative methods are routinely used for solving the ill-posed sparse linear systems arising in tomographic image reconstruction. Here we consider the algebraic reconstruction technique (ART) and the simultaneous iterative reconstruction techniques (SIRT), both of which rely on semiconv......Algebraic iterative methods are routinely used for solving the ill-posed sparse linear systems arising in tomographic image reconstruction. Here we consider the algebraic reconstruction technique (ART) and the simultaneous iterative reconstruction techniques (SIRT), both of which rely...... on semiconvergence. Block versions of these methods, based on a partitioning of the linear system, are able to combine the fast semiconvergence of ART with the better multicore properties of SIRT. These block methods separate into two classes: those that, in each iteration, access the blocks in a sequential manner...... a fixed relaxation parameter in each method, namely, the one that leads to the fastest semiconvergence. Computational results show that for multicore computers, the sequential approach is preferable....

Pediatric thermal injury: acute care and reconstruction update.

Science.gov (United States)

Armour, Alexis D; Billmire, David A

2009-07-01

The acute and reconstructive care of each pediatric burn patient presents unique challenges to the plastic surgeon and the burn care team. : The purpose of this review article is to highlight the interdependence between the acute and reconstructive needs of pediatric burn patients as it pertains to each anatomical site. Relevant principles of acute pediatric burn care and burn reconstruction are outlined, based on the authors' experience and review of the literature. The need for late reconstruction in pediatric burn survivors is significantly influenced by the acute surgical and rehabilitative treatments. With their vulnerability to airway swelling, hypothermia, pulmonary edema, and ischemia-reperfusion injury, pediatric patients with large burns require precise, life-saving treatment in the acute phase. Decision-making in pediatric burn reconstruction must take into account the patient's future growth, maturity, and often lack of suitable donor sites. Appropriately selected reconstructive techniques are essential to optimize function, appearance, and quality of life in pediatric burn survivors.

Advances in Bioprinting Technologies for Craniofacial Reconstruction.

Science.gov (United States)

Visscher, Dafydd O; Farré-Guasch, Elisabet; Helder, Marco N; Gibbs, Susan; Forouzanfar, Tymour; van Zuijlen, Paul P; Wolff, Jan

2016-09-01

Recent developments in craniofacial reconstruction have shown important advances in both the materials and methods used. While autogenous tissue is still considered to be the gold standard for these reconstructions, the harvesting procedure remains tedious and in many cases causes significant donor site morbidity. These limitations have subsequently led to the development of less invasive techniques such as 3D bioprinting that could offer possibilities to manufacture patient-tailored bioactive tissue constructs for craniofacial reconstruction. Here, we discuss the current technological and (pre)clinical advances of 3D bioprinting for use in craniofacial reconstruction and highlight the challenges that need to be addressed in the coming years. Copyright © 2016 Elsevier Ltd. All rights reserved.

Vertex Reconstruction in CMS

CERN Document Server

Chabanat, E; D'Hondt, J; Vanlaer, P; Prokofiev, K; Speer, T; Frühwirth, R; Waltenberger, W

2005-01-01

Because of the high track multiplicity in the final states expected in proton collisions at the LHC experiments, novel vertex reconstruction algorithms are required. The vertex reconstruction problem can be decomposed into a pattern recognition problem ("vertex finding") and an estimation problem ("vertex fitting"). Starting from least-square methods, ways to render the classical algorithms more robust are discussed and the statistical properties of the novel methods are shown. A whole set of different approaches for the vertex finding problem is presented and compared in relevant physics channels.

Algorithms for Reconstruction of Undersampled Atomic Force Microscopy Images Supplementary Material

DEFF Research Database (Denmark)

2017-01-01

Two Jupyter Notebooks showcasing reconstructions of undersampled atomic force microscopy images. The reconstructions were obtained using a variety of interpolation and reconstruction methods.......Two Jupyter Notebooks showcasing reconstructions of undersampled atomic force microscopy images. The reconstructions were obtained using a variety of interpolation and reconstruction methods....

RECONSTRUCTING WOMANHOOD IN TONY MORRISON'S BELOVED

Directory of Open Access Journals (Sweden)

Setefanus Suprajitno

2000-01-01

Full Text Available Tony Morrison's fifth novel, Beloved (1987, explores the degradation of slavery imposed upon slaves, even when they were owned by a "humane" slave master. The novel is set in the Reconstruction period, the period after the American civil war. The word reconstruction may be used for the Afro-Americans, especially for the Afro-American women who face double discrimination for being black and women. In dealing with women's oppression, Afro-American women have to reconstruct themselves as an act of survival, and to be aware of the horrors of the experiences which their ancestors had to go through.

GEODESIC RECONSTRUCTION, SADDLE ZONES & HIERARCHICAL SEGMENTATION

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Serge Beucher

2011-05-01

Full Text Available The morphological reconstruction based on geodesic operators, is a powerful tool in mathematical morphology. The general definition of this reconstruction supposes the use of a marker function f which is not necessarily related to the function g to be built. However, this paper deals with operations where the marker function is defined from given characteristic regions of the initial function f, as it is the case, for instance, for the extrema (maxima or minima but also for the saddle zones. Firstly, we show that the intuitive definition of a saddle zone is not easy to handle, especially when digitised images are involved. However, some of these saddle zones (regional ones also called overflow zones can be defined, this definition providing a simple algorithm to extract them. The second part of the paper is devoted to the use of these overflow zones as markers in image reconstruction. This reconstruction provides a new function which exhibits a new hierarchy of extrema. This hierarchy is equivalent to the hierarchy produced by the so-called waterfall algorithm. We explain why the waterfall algorithm can be achieved by performing a watershed transform of the function reconstructed by its initial watershed lines. Finally, some examples of use of this hierarchical segmentation are described.

Craniofacial Reconstruction Evaluation by Geodesic Network

Directory of Open Access Journals (Sweden)

Junli Zhao

2014-01-01

Full Text Available Craniofacial reconstruction is to estimate an individual’s face model from its skull. It has a widespread application in forensic medicine, archeology, medical cosmetic surgery, and so forth. However, little attention is paid to the evaluation of craniofacial reconstruction. This paper proposes an objective method to evaluate globally and locally the reconstructed craniofacial faces based on the geodesic network. Firstly, the geodesic networks of the reconstructed craniofacial face and the original face are built, respectively, by geodesics and isogeodesics, whose intersections are network vertices. Then, the absolute value of the correlation coefficient of the features of all corresponding geodesic network vertices between two models is taken as the holistic similarity, where the weighted average of the shape index values in a neighborhood is defined as the feature of each network vertex. Moreover, the geodesic network vertices of each model are divided into six subareas, that is, forehead, eyes, nose, mouth, cheeks, and chin, and the local similarity is measured for each subarea. Experiments using 100 pairs of reconstructed craniofacial faces and their corresponding original faces show that the evaluation by our method is roughly consistent with the subjective evaluation derived from thirty-five persons in five groups.

Accelerated Compressed Sensing Based CT Image Reconstruction.

Science.gov (United States)

Hashemi, SayedMasoud; Beheshti, Soosan; Gill, Patrick R; Paul, Narinder S; Cobbold, Richard S C

2015-01-01

In X-ray computed tomography (CT) an important objective is to reduce the radiation dose without significantly degrading the image quality. Compressed sensing (CS) enables the radiation dose to be reduced by producing diagnostic images from a limited number of projections. However, conventional CS-based algorithms are computationally intensive and time-consuming. We propose a new algorithm that accelerates the CS-based reconstruction by using a fast pseudopolar Fourier based Radon transform and rebinning the diverging fan beams to parallel beams. The reconstruction process is analyzed using a maximum-a-posterior approach, which is transformed into a weighted CS problem. The weights involved in the proposed model are calculated based on the statistical characteristics of the reconstruction process, which is formulated in terms of the measurement noise and rebinning interpolation error. Therefore, the proposed method not only accelerates the reconstruction, but also removes the rebinning and interpolation errors. Simulation results are shown for phantoms and a patient. For example, a 512 × 512 Shepp-Logan phantom when reconstructed from 128 rebinned projections using a conventional CS method had 10% error, whereas with the proposed method the reconstruction error was less than 1%. Moreover, computation times of less than 30 sec were obtained using a standard desktop computer without numerical optimization.

Accelerated Compressed Sensing Based CT Image Reconstruction

Directory of Open Access Journals (Sweden)

SayedMasoud Hashemi

2015-01-01

Full Text Available In X-ray computed tomography (CT an important objective is to reduce the radiation dose without significantly degrading the image quality. Compressed sensing (CS enables the radiation dose to be reduced by producing diagnostic images from a limited number of projections. However, conventional CS-based algorithms are computationally intensive and time-consuming. We propose a new algorithm that accelerates the CS-based reconstruction by using a fast pseudopolar Fourier based Radon transform and rebinning the diverging fan beams to parallel beams. The reconstruction process is analyzed using a maximum-a-posterior approach, which is transformed into a weighted CS problem. The weights involved in the proposed model are calculated based on the statistical characteristics of the reconstruction process, which is formulated in terms of the measurement noise and rebinning interpolation error. Therefore, the proposed method not only accelerates the reconstruction, but also removes the rebinning and interpolation errors. Simulation results are shown for phantoms and a patient. For example, a 512 × 512 Shepp-Logan phantom when reconstructed from 128 rebinned projections using a conventional CS method had 10% error, whereas with the proposed method the reconstruction error was less than 1%. Moreover, computation times of less than 30 sec were obtained using a standard desktop computer without numerical optimization.

UV Reconstruction Algorithm And Diurnal Cycle Variability

Science.gov (United States)

Curylo, Aleksander; Litynska, Zenobia; Krzyscin, Janusz; Bogdanska, Barbara

2009-03-01

UV reconstruction is a method of estimation of surface UV with the use of available actinometrical and aerological measurements. UV reconstruction is necessary for the study of long-term UV change. A typical series of UV measurements is not longer than 15 years, which is too short for trend estimation. The essential problem in the reconstruction algorithm is the good parameterization of clouds. In our previous algorithm we used an empirical relation between Cloud Modification Factor (CMF) in global radiation and CMF in UV. The CMF is defined as the ratio between measured and modelled irradiances. Clear sky irradiance was calculated with a solar radiative transfer model. In the proposed algorithm, the time variability of global radiation during the diurnal cycle is used as an additional source of information. For elaborating an improved reconstruction algorithm relevant data from Legionowo [52.4 N, 21.0 E, 96 m a.s.l], Poland were collected with the following instruments: NILU-UV multi channel radiometer, Kipp&Zonen pyranometer, radiosonde profiles of ozone, humidity and temperature. The proposed algorithm has been used for reconstruction of UV at four Polish sites: Mikolajki, Kolobrzeg, Warszawa-Bielany and Zakopane since the early 1960s. Krzyscin's reconstruction of total ozone has been used in the calculations.

Postmastectomy reconstruction: comparative analysis of the psychosocial, functional, and cosmetic effects of transverse rectus abdominis musculocutaneous flap versus breast implant reconstruction.

Science.gov (United States)

Cederna, P S; Yates, W R; Chang, P; Cram, A E; Ricciardelli, E J

1995-11-01

Over 40,000 postmastectomy breast reconstructions are performed annually. In this study, we investigated the psychosocial, functional, and cosmetic effects of transverse rectus abdominis musculocutaneous (TRAM) flap versus breast implant reconstruction. Thirty-three women who had undergone postmastectomy breast reconstruction were contacted by telephone and agreed to participate in the study. Twenty-two women completed the self-assessment questionnaires regarding their quality of life, psychological symptoms, functional status, body image, and global satisfaction. The TRAM and implant groups contained 8 and 14 patients, respectively. The groups were well matched for age, employment status, marital status, race, religion, and severity of medical and surgical illnesses. The average follow-up was 36 months. Statistical analysis of the responses revealed that women who had undergone TRAM flap reconstruction were more satisfied with how their reconstructed breast felt to the touch (p = .01), and there was a trend toward greater satisfaction with the appearance of their reconstructed breast (p = .08). However, these same patients identified more difficulties as far as functioning at work or school, performing vigorous physical activities, participating in community or religious activities, visiting with relatives, and interacting with male friends (p physical impairments as a result of their reconstruction.

CT angiography after carotid artery stenting: assessment of the utility of adaptive statistical iterative reconstruction and model-based iterative reconstruction

Energy Technology Data Exchange (ETDEWEB)

Kuya, Keita; Shinohara, Yuki; Fujii, Shinya; Ogawa, Toshihide [Tottori University, Division of Radiology, Department of Pathophysiological Therapeutic Science, Faculty of Medicine, Yonago (Japan); Sakamoto, Makoto; Watanabe, Takashi [Tottori University, Division of Neurosurgery, Department of Brain and Neurosciences, Faculty of Medicine, Yonago (Japan); Iwata, Naoki; Kishimoto, Junichi [Tottori University, Division of Clinical Radiology Faculty of Medicine, Yonago (Japan); Kaminou, Toshio [Osaka Minami Medical Center, Department of Radiology, Osaka (Japan)

2014-11-15

Follow-up CT angiography (CTA) is routinely performed for post-procedure management after carotid artery stenting (CAS). However, the stent lumen tends to be underestimated because of stent artifacts on CTA reconstructed with the filtered back projection (FBP) technique. We assessed the utility of new iterative reconstruction techniques, such as adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR), for CTA after CAS in comparison with FBP. In a phantom study, we evaluated the differences among the three reconstruction techniques with regard to the relationship between the stent luminal diameter and the degree of underestimation of stent luminal diameter. In a clinical study, 34 patients who underwent follow-up CTA after CAS were included. We compared the stent luminal diameters among FBP, ASIR, and MBIR, and performed visual assessment of low attenuation area (LAA) in the stent lumen using a three-point scale. In the phantom study, stent luminal diameter was increasingly underestimated as luminal diameter became smaller in all CTA images. Stent luminal diameter was larger with MBIR than with the other reconstruction techniques. Similarly, in the clinical study, stent luminal diameter was larger with MBIR than with the other reconstruction techniques. LAA detectability scores of MBIR were greater than or equal to those of FBP and ASIR in all cases. MBIR improved the accuracy of assessment of stent luminal diameter and LAA detectability in the stent lumen when compared with FBP and ASIR. We conclude that MBIR is a useful reconstruction technique for CTA after CAS. (orig.)

CT angiography after carotid artery stenting: assessment of the utility of adaptive statistical iterative reconstruction and model-based iterative reconstruction

International Nuclear Information System (INIS)

Kuya, Keita; Shinohara, Yuki; Fujii, Shinya; Ogawa, Toshihide; Sakamoto, Makoto; Watanabe, Takashi; Iwata, Naoki; Kishimoto, Junichi; Kaminou, Toshio

2014-01-01

Follow-up CT angiography (CTA) is routinely performed for post-procedure management after carotid artery stenting (CAS). However, the stent lumen tends to be underestimated because of stent artifacts on CTA reconstructed with the filtered back projection (FBP) technique. We assessed the utility of new iterative reconstruction techniques, such as adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR), for CTA after CAS in comparison with FBP. In a phantom study, we evaluated the differences among the three reconstruction techniques with regard to the relationship between the stent luminal diameter and the degree of underestimation of stent luminal diameter. In a clinical study, 34 patients who underwent follow-up CTA after CAS were included. We compared the stent luminal diameters among FBP, ASIR, and MBIR, and performed visual assessment of low attenuation area (LAA) in the stent lumen using a three-point scale. In the phantom study, stent luminal diameter was increasingly underestimated as luminal diameter became smaller in all CTA images. Stent luminal diameter was larger with MBIR than with the other reconstruction techniques. Similarly, in the clinical study, stent luminal diameter was larger with MBIR than with the other reconstruction techniques. LAA detectability scores of MBIR were greater than or equal to those of FBP and ASIR in all cases. MBIR improved the accuracy of assessment of stent luminal diameter and LAA detectability in the stent lumen when compared with FBP and ASIR. We conclude that MBIR is a useful reconstruction technique for CTA after CAS. (orig.)

The Theory of Variances in Equilibrium Reconstruction

International Nuclear Information System (INIS)

Zakharov, Leonid E.; Lewandowski, Jerome; Foley, Elizabeth L.; Levinton, Fred M.; Yuh, Howard Y.; Drozdov, Vladimir; McDonald, Darren

2008-01-01

The theory of variances of equilibrium reconstruction is presented. It complements existing practices with information regarding what kind of plasma profiles can be reconstructed, how accurately, and what remains beyond the abilities of diagnostic systems. The σ-curves, introduced by the present theory, give a quantitative assessment of quality of effectiveness of diagnostic systems in constraining equilibrium reconstructions. The theory also suggests a method for aligning the accuracy of measurements of different physical nature

Impact of Reconstruction Algorithms on CT Radiomic Features of Pulmonary Tumors: Analysis of Intra- and Inter-Reader Variability and Inter-Reconstruction Algorithm Variability.

Science.gov (United States)

Kim, Hyungjin; Park, Chang Min; Lee, Myunghee; Park, Sang Joon; Song, Yong Sub; Lee, Jong Hyuk; Hwang, Eui Jin; Goo, Jin Mo

2016-01-01

To identify the impact of reconstruction algorithms on CT radiomic features of pulmonary tumors and to reveal and compare the intra- and inter-reader and inter-reconstruction algorithm variability of each feature. Forty-two patients (M:F = 19:23; mean age, 60.43±10.56 years) with 42 pulmonary tumors (22.56±8.51mm) underwent contrast-enhanced CT scans, which were reconstructed with filtered back projection and commercial iterative reconstruction algorithm (level 3 and 5). Two readers independently segmented the whole tumor volume. Fifteen radiomic features were extracted and compared among reconstruction algorithms. Intra- and inter-reader variability and inter-reconstruction algorithm variability were calculated using coefficients of variation (CVs) and then compared. Among the 15 features, 5 first-order tumor intensity features and 4 gray level co-occurrence matrix (GLCM)-based features showed significant differences (palgorithms. As for the variability, effective diameter, sphericity, entropy, and GLCM entropy were the most robust features (CV≤5%). Inter-reader variability was larger than intra-reader or inter-reconstruction algorithm variability in 9 features. However, for entropy, homogeneity, and 4 GLCM-based features, inter-reconstruction algorithm variability was significantly greater than inter-reader variability (palgorithms. Inter-reconstruction algorithm variability was greater than inter-reader variability for entropy, homogeneity, and GLCM-based features.

One stage revision single-bundle anterior cruciate ligament reconstruction with impacted morselized bone graft following a failed double-bundle reconstruction

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Ho Jong Ra

2017-01-01

Full Text Available Although double-bundle anterior cruciate ligament (ACL reconstruction has theoretical benefits such as more accurate reproduction of ACL anatomy, it is technically more demanding surgery. This report describes the case of a one stage revision single-bundle ACL reconstruction after primary double-bundle ACL reconstruction. A professional dancer had an ACL previously reconstructed with a double-bundle technique, but the femoral tunnels were malpositioned resulting in residual laxity and rotational instability. The previous femoral tunnel positions were vertical and widened. The previous vertical tunnels were filled with impacted bone graft and a revision single-bundle ACL reconstruction was performed via the new femoral tunnel with a 2 O'clock position between the previous two tunnels. After 10 months of postoperative rehabilitation, the patient returned to professional dancing with sound bony union and without any residual instability.

Interactive reconstruction in single-photon tomography

International Nuclear Information System (INIS)

Miller, T.R.; Wallis, J.W.; Wilson, A.D.

1989-01-01

A new method is described to allow interactive selection of the reconstruction filter at the time of interpretation of images from single-photon tomography. In the filtered back projection algorithm, the only part of the reconstruction process requiring user interaction is the selection of the window function. Since the ramp and window filters have different purposes, they can be separated, placing the window at the end of the reconstruction process as a three-dimensional filter. All stages of reconstruction except the window filtering are performed before the physician begins to interpret the study. The three-dimensional filtering is performed very rapidly with use of the Chebyshev convolution algorithm. A 64 x 64 x 64 pixel cube of data is filtered in 13-33 s using filters of 3-11 lengths. Smaller volumes of image data can be filtered in less than 1 s; thus, the user can interactively choose any desired filter for a given tomographic study at the time of interpretation of the images. (orig.)

IRVE-II Post-Flight Trajectory Reconstruction

Science.gov (United States)

O'Keefe, Stephen A.; Bose, David M.

2010-01-01

NASA s Inflatable Re-entry Vehicle Experiment (IRVE) II successfully demonstrated an inflatable aerodynamic decelerator after being launched aboard a sounding rocket from Wallops Flight Facility (WFF). Preliminary day of flight data compared well with pre-flight Monte Carlo analysis, and a more complete trajectory reconstruction performed with an Extended Kalman Filter (EKF) approach followed. The reconstructed trajectory and comparisons to an attitude solution provided by NASA Sounding Rocket Operations Contract (NSROC) personnel at WFF are presented. Additional comparisons are made between the reconstructed trajectory and pre and post-flight Monte Carlo trajectory predictions. Alternative observations of the trajectory are summarized which leverage flight accelerometer measurements, the pre-flight aerodynamic database, and on-board flight video. Finally, analysis of the payload separation and aeroshell deployment events are presented. The flight trajectory is reconstructed to fidelity sufficient to assess overall project objectives related to flight dynamics and overall, IRVE-II flight dynamics are in line with expectations

DD4Hep based event reconstruction

CERN Document Server

AUTHOR|(SzGeCERN)683529; Frank, Markus; Gaede, Frank-Dieter; Hynds, Daniel; Lu, Shaojun; Nikiforou, Nikiforos; Petric, Marko; Simoniello, Rosa; Voutsinas, Georgios Gerasimos

The DD4HEP detector description toolkit offers a flexible and easy-to-use solution for the consistent and complete description of particle physics detectors in a single system. The sub-component DDREC provides a dedicated interface to the detector geometry as needed for event reconstruction. With DDREC there is no need to define an additional, separate reconstruction geometry as is often done in HEP, but one can transparently extend the existing detailed simulation model to be also used for the reconstruction. Based on the extension mechanism of DD4HEP, DDREC allows one to attach user defined data structures to detector elements at all levels of the geometry hierarchy. These data structures define a high level view onto the detectors describing their physical properties, such as measurement layers, point resolutions, and cell sizes. For the purpose of charged particle track reconstruction, dedicated surface objects can be attached to every volume in the detector geometry. These surfaces provide the measuremen...

Reconstructing warm inflation

Science.gov (United States)

Herrera, Ramón

2018-03-01

The reconstruction of a warm inflationary universe model from the scalar spectral index n_S(N) and the tensor to scalar ratio r( N) as a function of the number of e-folds N is studied. Under a general formalism we find the effective potential and the dissipative coefficient in terms of the cosmological parameters n_S and r considering the weak and strong dissipative stages under the slow roll approximation. As a specific example, we study the attractors for the index n_S given by nS-1∝ N^{-1} and for the ratio r∝ N^{-2}, in order to reconstruct the model of warm inflation. Here, expressions for the effective potential V(φ ) and the dissipation coefficient Γ (φ ) are obtained.

Challenges in the reconstruction of bilateral maxillectomy defects.

Science.gov (United States)

Joseph, Shawn T; Thankappan, Krishnakumar; Buggaveeti, Rahul; Sharma, Mohit; Mathew, Jimmy; Iyer, Subramania

2015-02-01

Bilateral maxillectomy defects, if not adequately reconstructed, can result in grave esthetic and functional problems. The purpose of this study was to investigate the outcome of reconstruction of such defects. This is a retrospective case series. The defects were analyzed for their components and the flaps used for reconstruction. Outcomes for flap loss and functional indices, including oral diet, speech, and dental rehabilitation, also were evaluated. Ten consecutive patients who underwent bilateral maxillectomy reconstruction received 14 flaps. Six patients had malignancies of the maxilla, and 4 patients had nonmalignant indications. Ten bony free flaps were used. Four soft tissue flaps were used. The fibula free flap was the most common flap used. Three patients had total flap loss. Seven patients were alive and available for functional evaluation. Of these, 4 were taking an oral diet with altered consistency and 2 were on a regular diet. Speech was intelligible in all patients. Only 2 patients opted for dental rehabilitation with removable dentures. Reconstruction after bilateral maxillectomy is essential to prevent esthetic and functional problems. Bony reconstruction is ideal. The fibula bone free flap is commonly used. The complexity of the defect makes reconstruction difficult and the initial success rate of free flaps is low. Secondary reconstructions after the initial flap failures were successful. A satisfactory functional outcome can be achieved. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Lower limb edema after arterial reconstruction, a comparison with lymph, reconstruction and DVT edema by RI scintigram

International Nuclear Information System (INIS)

Ojiro, M.; Takenosita, M.; Toshinaga, R.; Shimazu, H.; Nakajo, M.; Iwasita, S.

1991-01-01

Postoperative lower limb edema after arterial-reconstruction is common complication. However the precise mechanism of this process is not fully understood. In order to investigate this pathogenesis, it was studied whether the postoperative edema was affected by the various types of reconstruction, the materials, the degree of preoperative ischemia and the grade of improvement of ankle pressure index (API) after reconstruction retrospectively. Furthermore, by pertechnetate anion the difference of scintigraph pattern was studied in the lower limb and was compared with postoperative edema, lymph edema and acute deep vein thrombosis (DVT) with swelling limb. (author). 4 refs.; 2 figs

PWR-GALE, Radioactive Gaseous Release and Liquid Release from PWR

International Nuclear Information System (INIS)

Chandrasekaran, T.; Lee, J.Y.; Willis, C.A.

1988-01-01

1 - Description of program or function: The PWR-GALE (Boiling Water Reactor Gaseous and Liquid Effluents) Code is a computerized mathematical model for calculating the release of radioactive material in gaseous and liquid effluents from pressurized water reactors (PWRs). The calculations are based on data generated from operating reactors, field tests, laboratory tests, and plant-specific design considerations incorporated to reduce the quantity of radioactive materials that may be released to the environment. 2 - Method of solution: GALE calculates expected releases based on 1) standardized coolant activities derived from ANS Standards 18.1 Working Group recommendations, 2) release and transport mechanisms that result in the appearance of radioactive material in liquid and gaseous waste streams, 3) plant-specific design features used to reduce the quantities of radioactive materials ultimately released to the environs, and 4) information received on the operation of nuclear power plants. 3 - Restrictions on the complexity of the problem: The liquid release portion of GALE uses subroutines taken from the ORIGEN (CCC-217) to calculate radionuclide buildup and decay during collection, processing, and storage of liquid radwaste. Memory requirements for this part of the program are determined by the large nuclear data base accessed by these subroutines

A modified discrete algebraic reconstruction technique for multiple grey image reconstruction for limited angle range tomography.

Science.gov (United States)

Liang, Zhiting; Guan, Yong; Liu, Gang; Chen, Xiangyu; Li, Fahu; Guo, Pengfei; Tian, Yangchao

2016-03-01

The `missing wedge', which is due to a restricted rotation range, is a major challenge for quantitative analysis of an object using tomography. With prior knowledge of the grey levels, the discrete algebraic reconstruction technique (DART) is able to reconstruct objects accurately with projections in a limited angle range. However, the quality of the reconstructions declines as the number of grey levels increases. In this paper, a modified DART (MDART) was proposed, in which each independent region of homogeneous material was chosen as a research object, instead of the grey values. The grey values of each discrete region were estimated according to the solution of the linear projection equations. The iterative process of boundary pixels updating and correcting the grey values of each region was executed alternately. Simulation experiments of binary phantoms as well as multiple grey phantoms show that MDART is capable of achieving high-quality reconstructions with projections in a limited angle range. The interesting advancement of MDART is that neither prior knowledge of the grey values nor the number of grey levels is necessary.

Animated Reconstruction of Forensic Animation

OpenAIRE

Hala, Albert; Unver, Ertu

1998-01-01

An animated accident display in court can be significant evidentiary tool. Computer graphics animation reconstructions which can be shown in court are cost effective, save valuable time and illustrate complex and technical issues, are realistic and can prove or disprove arguments or theories with reference to the perplexing newtonian physics involved in many accidents: this technology may well revolutionise accident reconstruction, thus enabling prosecution and defence to be more effective in...

RIB FRACTURE AFTER BREAST RECONSTRUCTION WITH TISSUE EXPANDER

Directory of Open Access Journals (Sweden)

Uroš Ahčan

2009-08-01

Full Text Available Breast reconstruction with tissue expansion and later exchange with prosthesis is one of the most common methods for breast reconstruction. Women that are not appropriate for reconstruction with autologous tissue, women that have small breast or have a positive family history for breast cancer are most suitable for this type of reconstruction. Surgical technique of tissue expansion is relatively easy. Complications are rarely seen. With this case report we want to show the common, although occult existence of skeletal deformities in thorax after breast tissue expansion that may lead to rib fractures.

Time-based Reconstruction of Free-streaming Data in CBM

Science.gov (United States)

Akishina, Valentina; Kisel, Ivan; Vassiliev, Iouri; Zyzak, Maksym

2018-02-01

Traditional latency-limited trigger architectures typical for conventional experiments are inapplicable for the CBM experiment. Instead, CBM will ship and collect time-stamped data into a readout buffer in a form of a time-slice of a certain length and deliver it to a large computer farm, where online event reconstruction and selection will be performed. Grouping measurements into physical collisions must be performed in software and requires reconstruction not only in space, but also in time, the so-called 4-dimensional track reconstruction and event building. The tracks, reconstructed with 4D Cellular Automaton track finder, are combined into event-corresponding clusters according to the estimated time in the target position and the errors, obtained with the Kalman Filter method. The reconstructed events are given as inputs to the KF Particle Finder package for short-lived particle reconstruction. The results of time-based reconstruction of simulated collisions in CBM are presented and discussed in details.

Spiral scan long object reconstruction through PI line reconstruction

International Nuclear Information System (INIS)

Tam, K C; Hu, J; Sourbelle, K

2004-01-01

The response of a point object in a cone beam (CB) spiral scan is analysed. Based on the result, a reconstruction algorithm for long object imaging in spiral scan cone beam CT is developed. A region-of-interest (ROI) of the long object is scanned with a detector smaller than the ROI, and a portion of it can be reconstructed without contamination from overlaying materials. The top and bottom surfaces of the ROI are defined by two sets of PI lines near the two ends of the spiral path. With this novel definition of the top and bottom ROI surfaces and through the use of projective geometry, it is straightforward to partition the cone beam image into regions corresponding to projections of the ROI, the overlaying objects or both. This also simplifies computation at source positions near the spiral ends, and makes it possible to reduce radiation exposure near the spiral ends substantially through simple hardware collimation. Simulation results to validate the algorithm are presented

Distributed 3-D iterative reconstruction for quantitative SPECT

International Nuclear Information System (INIS)

Ju, Z.W.; Frey, E.C.; Tsui, B.M.W.

1995-01-01

The authors describe a distributed three dimensional (3-D) iterative reconstruction library for quantitative single-photon emission computed tomography (SPECT). This library includes 3-D projector-backprojector pairs (PBPs) and distributed 3-D iterative reconstruction algorithms. The 3-D PBPs accurately and efficiently model various combinations of the image degrading factors including attenuation, detector response and scatter response. These PBPs were validated by comparing projection data computed using the projectors with that from direct Monte Carlo (MC) simulations. The distributed 3-D iterative algorithms spread the projection-backprojection operations for all the projection angles over a heterogeneous network of single or multi-processor computers to reduce the reconstruction time. Based on a master/slave paradigm, these distributed algorithms provide dynamic load balancing and fault tolerance. The distributed algorithms were verified by comparing images reconstructed using both the distributed and non-distributed algorithms. Computation times for distributed 3-D reconstructions running on up to 4 identical processors were reduced by a factor approximately 80--90% times the number of the processors participating, compared to those for non-distributed 3-D reconstructions running on a single processor. When combined with faster affordable computers, this library provides an efficient means for implementing accurate reconstruction and compensation methods to improve quality and quantitative accuracy in SPECT images

Reconstruction of convex bodies from surface tensors

DEFF Research Database (Denmark)

Kousholt, Astrid; Kiderlen, Markus

. The output of the reconstruction algorithm is a polytope P, where the surface tensors of P and K are identical up to rank s. We establish a stability result based on a generalization of Wirtinger’s inequality that shows that for large s, two convex bodies are close in shape when they have identical surface...... that are translates of each other. An algorithm for reconstructing an unknown convex body in R 2 from its surface tensors up to a certain rank is presented. Using the reconstruction algorithm, the shape of an unknown convex body can be approximated when only a finite number s of surface tensors are available...... tensors up to rank s. This is used to establish consistency of the developed reconstruction algorithm....

Hip dislocation in cerebral palsy: evolution of the contralateral side after reconstructive surgery

Directory of Open Access Journals (Sweden)

João Caetano Munhoz Abdo

2016-06-01

Full Text Available ABSTRACT OBJECTIVE: To evaluate the progression of the contralateral hip after unilateral reconstruction of hip dislocation in patients classified as GMFCS IV-V; and to identify potential prognostic factors for their evolution. METHODS: This was a retrospective study on 17 patients with spastic cerebral palsy, who were classified on the GMFCS scale (Gross Motor Functional Classification System as degrees IV and V, and who underwent unilateral reconstruction surgery to treat hip dislocation (adductor release, femoral varus osteotomy and acetabuloplasty. The minimum postoperative follow-up was 30 months. The clinical parameters evaluated were sex, age at time of surgery, length of follow-up after surgery and range of abduction. The treatment parameters were use/nonuse of femoral shortening, application of botulinum toxin and any previous muscle releases. The radiographic parameters were Reimer's extrusion index (REI, acetabular angle (AA and the continuity of Shenton's line. RESULTS: Among the 17 patients evaluated, eight presented dislocation (group I and nine did not (group II. Group I comprised three males and five females; group II comprised one male and eight females. The mean age at the time of surgery among the group I patients was 62 months and the mean follow-up was 62 months. In group II, these were 98 and 83 months, respectively. There was a trend in which patients of greater age did not evolve with contralateral dislocation. Among the nine patients with the combination of REI < 30% and AA < 25°, only one presented dislocation during the follow-up. Contralateral subluxation occurred within the first two years after the surgery. CONCLUSION: Hips presenting REI < 30° and AA < 25° do not tend to evolve to subluxation and can be kept under observation. Preoperative clinical and radiographic measurements alone are not useful for indicating the natural evolution of non- operated hips. The critical period for subluxation is the first two

Comparative interpretations of renormalization inversion technique for reconstructing unknown emissions from measured atmospheric concentrations

Science.gov (United States)

Singh, Sarvesh Kumar; Kumar, Pramod; Rani, Raj; Turbelin, Grégory

2017-04-01

The study highlights a theoretical comparison and various interpretations of a recent inversion technique, called renormalization, developed for the reconstruction of unknown tracer emissions from their measured concentrations. The comparative interpretations are presented in relation to the other inversion techniques based on principle of regularization, Bayesian, minimum norm, maximum entropy on mean, and model resolution optimization. It is shown that the renormalization technique can be interpreted in a similar manner to other techniques, with a practical choice of a priori information and error statistics, while eliminating the need of additional constraints. The study shows that the proposed weight matrix and weighted Gram matrix offer a suitable deterministic choice to the background error and measurement covariance matrices, respectively, in the absence of statistical knowledge about background and measurement errors. The technique is advantageous since it (i) utilizes weights representing a priori information apparent to the monitoring network, (ii) avoids dependence on background source estimates, (iii) improves on alternative choices for the error statistics, (iv) overcomes the colocalization problem in a natural manner, and (v) provides an optimally resolved source reconstruction. A comparative illustration of source retrieval is made by using the real measurements from a continuous point release conducted in Fusion Field Trials, Dugway Proving Ground, Utah.

Primary vertex reconstruction with the ATLAS detector

International Nuclear Information System (INIS)

Meloni, F.

2016-01-01

Efficient and precise reconstruction of the primary vertex in a LHC collision is essential for determining the full kinematic properties of a hard-scatter event and of soft interactions as a measure of the amount of pile-up. The reconstruction of primary vertices in the busy, high pile-up environment of Run-2 of the LHC is a challenging task. The algorithms developed by the ATLAS experiments to reconstruct multiple vertices with small spatial separation are presented.

Porous media microstructure reconstruction using pixel-based and object-based simulated annealing: comparison with other reconstruction methods

Energy Technology Data Exchange (ETDEWEB)

Diogenes, Alysson N.; Santos, Luis O.E. dos; Fernandes, Celso P. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Appoloni, Carlos R. [Universidade Estadual de Londrina (UEL), PR (Brazil)

2008-07-01

The reservoir rocks physical properties are usually obtained in laboratory, through standard experiments. These experiments are often very expensive and time-consuming. Hence, the digital image analysis techniques are a very fast and low cost methodology for physical properties prediction, knowing only geometrical parameters measured from the rock microstructure thin sections. This research analyzes two methods for porous media reconstruction using the relaxation method simulated annealing. Using geometrical parameters measured from rock thin sections, it is possible to construct a three-dimensional (3D) model of the microstructure. We assume statistical homogeneity and isotropy and the 3D model maintains porosity spatial correlation, chord size distribution and d 3-4 distance transform distribution for a pixel-based reconstruction and spatial correlation for an object-based reconstruction. The 2D and 3D preliminary results are compared with microstructures reconstructed by truncated Gaussian methods. As this research is in its beginning, only the 2D results will be presented. (author)

Reconstruction of Defects After Fournier Gangrene: A Systematic Review.

Science.gov (United States)

Karian, Laurel S; Chung, Stella Y; Lee, Edward S

2015-01-01

Reconstruction of scrotal defects after Fournier gangrene is often achieved with skin grafts or flaps, but there is no general consensus on the best method of reconstruction or how to approach the exposed testicle. We systematically reviewed the literature addressing methods of reconstruction of Fournier defects after debridement. PubMed and Cochrane databases were searched from 1950 to 2013. Inclusion criteria were reconstruction for Fournier defects, patients 18 to 90 years old, and reconstructive complication rates reported as whole numbers or percentages. Exclusion criteria were studies focused on methods of debridement or other phases of care rather than reconstruction, studies with fewer than 5 male patients with Fournier defects, literature reviews, and articles not in English. The initial search yielded 982 studies, which was refined to 16 studies with a total pool of 425 patients. There were 25 (5.9%) patients with defects that healed by secondary intention, 44 (10.4%) with delayed primary closure, 36 (8.5%) with implantation of the testicle in a medial thigh pocket, 6 (1.4%) with loose wound approximation, 96 (22.6%) with skin grafts, 68 (16.0%) with scrotal advancement flaps, 128 (30.1%) with flaps, and 22 (5.2%) with flaps or skin grafts in combination with tissue adhesives. Four outcomes were evaluated: number of patients, defect size, method of reconstruction, and wound-healing complications. Most reconstructive techniques provide reliable coverage and protection of testicular function with an acceptable cosmetic result. There is no conclusive evidence to support flap coverage of exposed testes rather than skin graft. A reconstructive algorithm is proposed. Skin grafting or flap reconstruction is recommended for defects larger than 50% of the scrotum or extending beyond the scrotum, whereas scrotal advancement flap reconstruction or healing by secondary intention is best for defects confined to less than 50% of the scrotum that cannot be closed

High-speed reconstruction of compressed images

Science.gov (United States)

Cox, Jerome R., Jr.; Moore, Stephen M.

1990-07-01

A compression scheme is described that allows high-definition radiological images with greater than 8-bit intensity resolution to be represented by 8-bit pixels. Reconstruction of the images with their original intensity resolution can be carried out by means of a pipeline architecture suitable for compact, high-speed implementation. A reconstruction system is described that can be fabricated according to this approach and placed between an 8-bit display buffer and the display's video system thereby allowing contrast control of images at video rates. Results for 50 CR chest images are described showing that error-free reconstruction of the original 10-bit CR images can be achieved.

Two-and three-dimensional CT reconstruction

International Nuclear Information System (INIS)

Fishman, E.K.; Ney, D.R.; Magid, D.

1990-01-01

This paper determines the optimal imaging sequence for creating two- and three-dimensional (2D/3D) skeletal reconstructions from CT data. A cadaver femur, a bone phantom, and a surgically created fracture were scanned with varying protocols to determine the optimal protocol for creating 2D/3D images. The scanning protocols used varying section thickness (2, 4, and 8 mm) as well as scan spacing (2, 3, 4 and 8 mm). All images were reconstructed into 2D data sets with a bicubic interpolation and 3D datasets with volumetric rendering. The results were reviewed by two reviewers to determine the quality of images reconstruction

Arthroscopic-Assisted Triangular Fibrocartilage Complex Reconstruction.

Science.gov (United States)

Chu-Kay Mak, Michael; Ho, Pak-Cheong

2017-11-01

Injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. Volar and dorsal radioulnar ligaments and their foveal insertion are the most important stabilizing components of the TFCC. In irreparable tears, anatomic reconstruction of the TFCC aims to restore normal biomechanics and stability of the distal radioulnar joint. We proposed a novel arthroscopic-assisted technique using a palmaris longus tendon graft. Arthroscopic-assisted TFCC reconstruction is a safe and effective approach with outcomes comparable to conventional open reconstruction and may result in a better range of motion from minimizing soft tissue dissection and subsequent scarring. Copyright © 2017 Elsevier Inc. All rights reserved.

The Reconstruction Toolkit (RTK), an open-source cone-beam CT reconstruction toolkit based on the Insight Toolkit (ITK)

International Nuclear Information System (INIS)

Rit, S; Vila Oliva, M; Sarrut, D; Brousmiche, S; Labarbe, R; Sharp, G C

2014-01-01

We propose the Reconstruction Toolkit (RTK, http://www.openrtk.org), an open-source toolkit for fast cone-beam CT reconstruction, based on the Insight Toolkit (ITK) and using GPU code extracted from Plastimatch. RTK is developed by an open consortium (see affiliations) under the non-contaminating Apache 2.0 license. The quality of the platform is daily checked with regression tests in partnership with Kitware, the company supporting ITK. Several features are already available: Elekta, Varian and IBA inputs, multi-threaded Feldkamp-David-Kress reconstruction on CPU and GPU, Parker short scan weighting, multi-threaded CPU and GPU forward projectors, etc. Each feature is either accessible through command line tools or C++ classes that can be included in independent software. A MIDAS community has been opened to share CatPhan datasets of several vendors (Elekta, Varian and IBA). RTK will be used in the upcoming cone-beam CT scanner developed by IBA for proton therapy rooms. Many features are under development: new input format support, iterative reconstruction, hybrid Monte Carlo / deterministic CBCT simulation, etc. RTK has been built to freely share tomographic reconstruction developments between researchers and is open for new contributions.

Model-based iterative reconstruction for reduction of radiation dose in abdominopelvic CT: comparison to adaptive statistical iterative reconstruction.

Science.gov (United States)

Yasaka, Koichiro; Katsura, Masaki; Akahane, Masaaki; Sato, Jiro; Matsuda, Izuru; Ohtomo, Kuni

2013-12-01

To evaluate dose reduction and image quality of abdominopelvic computed tomography (CT) reconstructed with model-based iterative reconstruction (MBIR) compared to adaptive statistical iterative reconstruction (ASIR). In this prospective study, 85 patients underwent referential-, low-, and ultralow-dose unenhanced abdominopelvic CT. Images were reconstructed with ASIR for low-dose (L-ASIR) and ultralow-dose CT (UL-ASIR), and with MBIR for ultralow-dose CT (UL-MBIR). Image noise was measured in the abdominal aorta and iliopsoas muscle. Subjective image analyses and a lesion detection study (adrenal nodules) were conducted by two blinded radiologists. A reference standard was established by a consensus panel of two different radiologists using referential-dose CT reconstructed with filtered back projection. Compared to low-dose CT, there was a 63% decrease in dose-length product with ultralow-dose CT. UL-MBIR had significantly lower image noise than L-ASIR and UL-ASIR (all pASIR and UL-ASIR (all pASIR in diagnostic acceptability (p>0.65), or diagnostic performance for adrenal nodules (p>0.87). MBIR significantly improves image noise and streak artifacts compared to ASIR, and can achieve radiation dose reduction without severely compromising image quality.

LHCb jet reconstruction

International Nuclear Information System (INIS)

Francisco, Oscar; Rangel, Murilo; Barter, William; Bursche, Albert; Potterat, Cedric; Coco, Victor

2012-01-01

Full text: The Large Hadron Collider (LHC) is the most powerful particle accelerator in the world. It has been designed to collide proton beams at an energy up to 14 TeV in the center of mass. In 2011, the data taking was done with a center of mass energy of 7 TeV, the instant luminosity has reached values greater than 4 X 10 32 cm -2 s -1 and the integrated luminosity reached the value of 1,02fb -1 on the LHCb. The jet reconstruction is fundamental to observe events that can be used to test perturbative QCD (pQCD). It also provides a way to observe standard model channels and searches for new physics like SUSY. The anti-kt algorithm is a jet reconstruction algorithm that is based on the distance of the particles on the space ηX φ and on the transverse momentum of particles. To maximize the energy resolution all information about the trackers and the colorimeters are used on the LHCb experiment to create objects called particle flow objects that are used as input to anti-kt algorithm. The LHCb is specially interesting for jets studies because its η region is complementary to the others main experiments on LHC. We will present the first results of jet reconstruction using 2011 LHCb data. (author)

LHCb jet reconstruction

Energy Technology Data Exchange (ETDEWEB)

Francisco, Oscar; Rangel, Murilo [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Barter, William [University of Cambridge, Cambridge (United Kingdom); Bursche, Albert [Universitat Zurich, Zurich (Switzerland); Potterat, Cedric [Universitat de Barcelona, Barcelona (Spain); Coco, Victor [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands)

2012-07-01

Full text: The Large Hadron Collider (LHC) is the most powerful particle accelerator in the world. It has been designed to collide proton beams at an energy up to 14 TeV in the center of mass. In 2011, the data taking was done with a center of mass energy of 7 TeV, the instant luminosity has reached values greater than 4 X 10{sup 32} cm{sup -2}s{sup -1} and the integrated luminosity reached the value of 1,02fb{sup -1} on the LHCb. The jet reconstruction is fundamental to observe events that can be used to test perturbative QCD (pQCD). It also provides a way to observe standard model channels and searches for new physics like SUSY. The anti-kt algorithm is a jet reconstruction algorithm that is based on the distance of the particles on the space {eta}X {phi} and on the transverse momentum of particles. To maximize the energy resolution all information about the trackers and the colorimeters are used on the LHCb experiment to create objects called particle flow objects that are used as input to anti-kt algorithm. The LHCb is specially interesting for jets studies because its {eta} region is complementary to the others main experiments on LHC. We will present the first results of jet reconstruction using 2011 LHCb data. (author)

Denoising multicriterion iterative reconstruction in emission spectral tomography

Science.gov (United States)

Wan, Xiong; Yin, Aihan

2007-03-01

In the study of optical testing, the computed tomogaphy technique has been widely adopted to reconstruct three-dimensional distributions of physical parameters of various kinds of fluid fields, such as flame, plasma, etc. In most cases, projection data are often stained by noise due to environmental disturbance, instrumental inaccuracy, and other random interruptions. To improve the reconstruction performance in noisy cases, an algorithm that combines a self-adaptive prefiltering denoising approach (SPDA) with a multicriterion iterative reconstruction (MCIR) is proposed and studied. First, the level of noise is approximately estimated with a frequency domain statistical method. Then the cutoff frequency of a Butterworth low-pass filter was established based on the evaluated noise energy. After the SPDA processing, the MCIR algorithm was adopted for limited-view optical computed tomography reconstruction. Simulated reconstruction of two test phantoms and a flame emission spectral tomography experiment were employed to evaluate the performance of SPDA-MCIR in noisy cases. Comparison with some traditional methods and experiment results showed that the SPDA-MCIR combination had obvious improvement in the case of noisy data reconstructions.

Recovery after abdominal wall reconstruction

DEFF Research Database (Denmark)

Jensen, Kristian Kiim

2017-01-01

Incisional hernia is a common long-term complication to abdominal surgery, occurring in more than 20% of all patients. Some of these hernias become giant and affect patients in several ways. This patient group often experiences pain, decreased perceived body image, and loss of physical function......, which results in a need for surgical repair of the giant hernia, known as abdominal wall reconstruction. In the current thesis, patients with a giant hernia were examined to achieve a better understanding of their physical and psychological function before and after abdominal wall reconstruction. Study...... was lacking. Study II was a case-control study of the effects of an enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction for a giant hernia. Sixteen consecutive patients were included prospectively after the implementation of a new enhanced recovery after surgery...

Optimisation of the ATLAS Track Reconstruction Software for Run-2

CERN Document Server

Salzburger, Andreas; The ATLAS collaboration

2015-01-01

Track reconstruction is one of the most complex element of the reconstruction of events recorded by ATLAS from collisions delivered by the LHC. It is the most time consuming reconstruction component in high luminosity environments. The flat budget projections for computing resources for Run-2 of the LHC together with the demands of reconstructing higher pile-up collision data at rates more than double those in Run-1 (an increase from 400 Hz to 1 kHz in trigger output) have put stringent requirements on the track reconstruction software. The ATLAS experiment has performed a two year long software campaign which aimed to reduce the reconstruction rate by a factor of three to meet the resource limitations for Run-2: the majority of the changes to achieve this were improvements to the track reconstruction software. The CPU processing time of ATLAS track reconstruction was reduced by more than a factor of three during this campaign without any loss of output information of the track reconstruction. We present the ...

Trends in Materials Science for Ligament Reconstruction.

Science.gov (United States)

Sava, Oana Roxana; Sava, Daniel Florin; Radulescu, Marius; Albu, Madalina Georgiana; Ficai, Denisa; Veloz-Castillo, Maria Fernanda; Mendez-Rojas, Miguel Angel; Ficai, Anton

2017-01-01

The number of ligament injuries increases every year and concomitantly the need for materials or systems that can reconstruct the ligament. Limitations imposed by autografts and allografts in ligament reconstruction together with the advances in materials science and biology have attracted a lot of interest for developing systems and materials for ligament replacement or reconstruction. This review intends to synthesize the major steps taken in the development of polymer-based materials for anterior cruciate ligament, their advantages and drawbacks and the results of different in vitro and in vivo tests. Until present, there is no successful polymer system for ligament reconstruction implanted in humans. The developing field of synthetic polymers for ligament reconstruction still has a lot of potential. In addition, several nano-structured materials, made of nanofibers or in the form of ceramic/polymeric nanocomposites, are attracting the interest of several groups due to their potential use as engineered scaffolds that mimic the native environment of cells, increasing the chances for tissue regeneration. Here, we review the last 15 years of literature in order to obtain a better understanding on the state-of-the-art that includes the usage of nano- and poly-meric materials for ligament reconstruction, and to draw perspectives on the future development of the field. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Breast reconstruction: current and future options

Directory of Open Access Journals (Sweden)

Paul Jr H

2011-08-01

Full Text Available Henry Paul Jr1, Tahira I Prendergast2, Bryson Nicholson2, Shenita White2, Wayne AI Frederick2,31Departments of Plastic Surgery, 2General Surgery, Howard University Hospital, 3Cancer Center, Howard University, Washington, DC, USAAbstract: When initiated by the devastating diagnosis of cancer, post ablative breast restoration has at its core the goal of restoring anatomic normalcy. The concepts of body image, wholeness, and overall well-being have been introduced to explain the paramount psychological influence the breast has on both individuals and society as a whole. Hence, a growing subspecialty has been established to recreate or simulate the lost breast. At least one third of breast cancer victims consider breast reconstruction. Breast reconstruction post mastectomy may be offered at the time of mastectomy or delayed post mastectomy after adjuvant therapy. This may be utilizing autologous tissues or implants and each has risks and benefits, especially when considering adjuvant therapy. In addition, there has been a move away from a traditional mastectomy to less invasive, but still curative procedures, such as skin-sparing and nipple-sparing mastectomy. These procedures provide the breast envelope to facilitate reconstruction. This paper reviews the primary issues in breast reconstruction, as well as their psychologic, oncologic, and social impact.Keywords: breast restoration, body image, breast reconstruction, mastectomy

Distance weighting for improved tomographic reconstructions

International Nuclear Information System (INIS)

Koeppe, R.A.; Holden, J.E.

1984-01-01

An improved method for the reconstruction of emission computed axial tomography images has been developed. The method is a modification of filtered back-projection, where the back projected values are weighted to reflect the loss of formation, with distance from the camera, which is inherent in gamma camera imaging. This information loss is a result of: loss of spatial resolution with distance, attenuation, and scatter. The weighting scheme can best be described by considering the contributions of any two opposing views to the reconstruction image pixels. The weight applied to the projections of one view is set to equal the relative amount of the original activity that was initially received in that projection, assuming a uniform attenuating medium. This yields a weighting value which is a function of distance into the image with a value of one for pixels ''near the camera'', a value of .5 at the image center, and a value of zero on the opposite side. Tomographic reconstructions produced with this method show improved spatial resolution when compared to conventional 360 0 reconstructions. The improvement is in the tangential direction, where simulations have indicated a FWHM improvement of 1 to 1.5 millimeters. The resolution in the radial direction is essentially the same for both methods. Visual inspection of the reconstructed images show improved resolution and contrast

Photoacoustic image reconstruction: a quantitative analysis

Science.gov (United States)

Sperl, Jonathan I.; Zell, Karin; Menzenbach, Peter; Haisch, Christoph; Ketzer, Stephan; Marquart, Markus; Koenig, Hartmut; Vogel, Mika W.

2007-07-01

Photoacoustic imaging is a promising new way to generate unprecedented contrast in ultrasound diagnostic imaging. It differs from other medical imaging approaches, in that it provides spatially resolved information about optical absorption of targeted tissue structures. Because the data acquisition process deviates from standard clinical ultrasound, choice of the proper image reconstruction method is crucial for successful application of the technique. In the literature, multiple approaches have been advocated, and the purpose of this paper is to compare four reconstruction techniques. Thereby, we focused on resolution limits, stability, reconstruction speed, and SNR. We generated experimental and simulated data and reconstructed images of the pressure distribution using four different methods: delay-and-sum (DnS), circular backprojection (CBP), generalized 2D Hough transform (HTA), and Fourier transform (FTA). All methods were able to depict the point sources properly. DnS and CBP produce blurred images containing typical superposition artifacts. The HTA provides excellent SNR and allows a good point source separation. The FTA is the fastest and shows the best FWHM. In our study, we found the FTA to show the best overall performance. It allows a very fast and theoretically exact reconstruction. Only a hardware-implemented DnS might be faster and enable real-time imaging. A commercial system may also perform several methods to fully utilize the new contrast mechanism and guarantee optimal resolution and fidelity.

Charge reconstruction in large-area photomultipliers

Science.gov (United States)

Grassi, M.; Montuschi, M.; Baldoncini, M.; Mantovani, F.; Ricci, B.; Andronico, G.; Antonelli, V.; Bellato, M.; Bernieri, E.; Brigatti, A.; Brugnera, R.; Budano, A.; Buscemi, M.; Bussino, S.; Caruso, R.; Chiesa, D.; Corti, D.; Dal Corso, F.; Ding, X. F.; Dusini, S.; Fabbri, A.; Fiorentini, G.; Ford, R.; Formozov, A.; Galet, G.; Garfagnini, A.; Giammarchi, M.; Giaz, A.; Insolia, A.; Isocrate, R.; Lippi, I.; Longhitano, F.; Lo Presti, D.; Lombardi, P.; Marini, F.; Mari, S. M.; Martellini, C.; Meroni, E.; Mezzetto, M.; Miramonti, L.; Monforte, S.; Nastasi, M.; Ortica, F.; Paoloni, A.; Parmeggiano, S.; Pedretti, D.; Pelliccia, N.; Pompilio, R.; Previtali, E.; Ranucci, G.; Re, A. C.; Romani, A.; Saggese, P.; Salamanna, G.; Sawy, F. H.; Settanta, G.; Sisti, M.; Sirignano, C.; Spinetti, M.; Stanco, L.; Strati, V.; Verde, G.; Votano, L.

2018-02-01

Large-area PhotoMultiplier Tubes (PMT) allow to efficiently instrument Liquid Scintillator (LS) neutrino detectors, where large target masses are pivotal to compensate for neutrinos' extremely elusive nature. Depending on the detector light yield, several scintillation photons stemming from the same neutrino interaction are likely to hit a single PMT in a few tens/hundreds of nanoseconds, resulting in several photoelectrons (PEs) to pile-up at the PMT anode. In such scenario, the signal generated by each PE is entangled to the others, and an accurate PMT charge reconstruction becomes challenging. This manuscript describes an experimental method able to address the PMT charge reconstruction in the case of large PE pile-up, providing an unbiased charge estimator at the permille level up to 15 detected PEs. The method is based on a signal filtering technique (Wiener filter) which suppresses the noise due to both PMT and readout electronics, and on a Fourier-based deconvolution able to minimize the influence of signal distortions—such as an overshoot. The analysis of simulated PMT waveforms shows that the slope of a linear regression modeling the relation between reconstructed and true charge values improves from 0.769 ± 0.001 (without deconvolution) to 0.989 ± 0.001 (with deconvolution), where unitary slope implies perfect reconstruction. A C++ implementation of the charge reconstruction algorithm is available online at [1].

Flash release an alternative for releasing complex MEMS devices

NARCIS (Netherlands)

Deladi, S.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

2004-01-01

A novel time-saving and cost-effective release technique has been developed and is described. The physical nature of the process is explained in combination with experimental observations. The results of the flash release process are compared with those of freeze-drying and supercritical CO2

Tumescent mastectomy technique in autologous breast reconstruction.

Science.gov (United States)

Vargas, Christina R; Koolen, Pieter G L; Ho, Olivia A; Ricci, Joseph A; Tobias, Adam M; Lin, Samuel J; Lee, Bernard T

2015-10-01

Use of the tumescent mastectomy technique has been reported to facilitate development of a hydrodissection plane, reduce blood loss, and provide adjunct analgesia. Previous studies suggest that tumescent dissection may contribute to adverse outcomes after immediate implant reconstruction; however, its effect on autologous microsurgical reconstruction has not been established. A retrospective review was conducted of all immediate microsurgical breast reconstruction procedures at a single academic center between January 2004 and December 2013. Records were queried for age, body mass index, mastectomy weight, diabetes, hypertension, smoking, preoperative radiation, reconstruction flap type, and autologous flap weight. Outcomes of interest were mastectomy skin necrosis, complete and partial flap loss, return to the operating room, breast hematoma, seroma, and infection. There were 730 immediate autologous breast reconstructions performed during the study period; 46% with the tumescent dissection technique. Groups were similar with respect to baseline patient and procedural characteristics. Univariate analysis revealed no significant difference in the incidence of mastectomy skin necrosis, complete or partial flap loss, return to the operating room, operative time, estimated blood loss, recurrence, breast hematoma, seroma, or infection in patients undergoing tumescent mastectomy. Multivariate analysis also demonstrated no significant association between the use of tumescent technique and postoperative breast mastectomy skin necrosis (P = 0.980), hematoma (P = 0.759), or seroma (P = 0.340). Use of the tumescent dissection technique during mastectomy is not significantly associated with adverse outcomes after microsurgical breast reconstruction. Despite concern for its impact on implant reconstruction, our findings suggest that this method can be used safely preceding autologous procedures. Copyright © 2015 Elsevier Inc. All rights reserved.

Algorithms for reconstructing images for industrial applications

International Nuclear Information System (INIS)

Lopes, R.T.; Crispim, V.R.

1986-01-01

Several algorithms for reconstructing objects from their projections are being studied in our Laboratory, for industrial applications. Such algorithms are useful locating the position and shape of different composition of materials in the object. A Comparative study of two algorithms is made. The two investigated algorithsm are: The MART (Multiplicative - Algebraic Reconstruction Technique) and the Convolution Method. The comparison are carried out from the point view of the quality of the image reconstructed, number of views and cost. (Author) [pt

Ways of improving preparatory stage and reconstruction of coking plants

Energy Technology Data Exchange (ETDEWEB)

Rozenfel' d, M.S.; Martynenko, V.M.; Svyatogorov, A.A.; Kvitkin, I.A.; Zhurba, A.I.; Gurtovnik, P.F.

1987-06-01

Discusses economic and technological aspects of coking plant reconstruction and modernization in the USSR. Effects of standardized technologies on plant reconstruction are analyzed. A standardized planning procedure jointly developed by research institutes in the USSR for plant modernization or reconstruction is discussed: selecting the optimum reconstruction and repair time, sequence of operations without stoppage of a coke oven battery, coke oven cooling, repair of coke oven liners, heating systems, coke oven equipment, drying, initial heating, testing battery equipment. The procedure is aimed at reducing coke losses and eliminating delays during reconstruction operations. A graphic method for modelling plant reconstruction is discussed.

RECONSTRUCTION OF THE SOUND CONDUCTING MECHANISM ...

African Journals Online (AJOL)

In this progress report on a new tympanoplastic procedure for reconstructing a disrupted sound conducting mechanism characterized by destruction of the handle of the malleus, it is shown that by reconstructing a tympanic membrane and a handle of the malleus from a patient's own tissue and by utilizing a prosthesis for ...

Predicting supramolecular self-assembly on reconstructed metal surfaces

Science.gov (United States)

Roussel, Thomas J.; Barrena, Esther; Ocal, Carmen; Faraudo, Jordi

2014-06-01

The prediction of supramolecular self-assembly onto solid surfaces is still challenging in many situations of interest for nanoscience. In particular, no previous simulation approach has been capable to simulate large self-assembly patterns of organic molecules over reconstructed surfaces (which have periodicities over large distances) due to the large number of surface atoms and adsorbing molecules involved. Using a novel simulation technique, we report here large scale simulations of the self-assembly patterns of an organic molecule (DIP) over different reconstructions of the Au(111) surface. We show that on particular reconstructions, the molecule-molecule interactions are enhanced in a way that long-range order is promoted. Also, the presence of a distortion in a reconstructed surface pattern not only induces the presence of long-range order but also is able to drive the organization of DIP into two coexisting homochiral domains, in quantitative agreement with STM experiments. On the other hand, only short range order is obtained in other reconstructions of the Au(111) surface. The simulation strategy opens interesting perspectives to tune the supramolecular structure by simulation design and surface engineering if choosing the right molecular building blocks and stabilising the chosen reconstruction pattern.The prediction of supramolecular self-assembly onto solid surfaces is still challenging in many situations of interest for nanoscience. In particular, no previous simulation approach has been capable to simulate large self-assembly patterns of organic molecules over reconstructed surfaces (which have periodicities over large distances) due to the large number of surface atoms and adsorbing molecules involved. Using a novel simulation technique, we report here large scale simulations of the self-assembly patterns of an organic molecule (DIP) over different reconstructions of the Au(111) surface. We show that on particular reconstructions, the molecule

Parallel CT image reconstruction based on GPUs

International Nuclear Information System (INIS)

Flores, Liubov A.; Vidal, Vicent; Mayo, Patricia; Rodenas, Francisco; Verdú, Gumersindo

2014-01-01

In X-ray computed tomography (CT) iterative methods are more suitable for the reconstruction of images with high contrast and precision in noisy conditions from a small number of projections. However, in practice, these methods are not widely used due to the high computational cost of their implementation. Nowadays technology provides the possibility to reduce effectively this drawback. It is the goal of this work to develop a fast GPU-based algorithm to reconstruct high quality images from under sampled and noisy projection data. - Highlights: • We developed GPU-based iterative algorithm to reconstruct images. • Iterative algorithms are capable to reconstruct images from under sampled set of projections. • The computer cost of the implementation of the developed algorithm is low. • The efficiency of the algorithm increases for the large scale problems

3D reconstruction based on light field images

Science.gov (United States)

Zhu, Dong; Wu, Chunhong; Liu, Yunluo; Fu, Dongmei

2018-04-01

This paper proposed a method of reconstructing three-dimensional (3D) scene from two light field images capture by Lytro illium. The work was carried out by first extracting the sub-aperture images from light field images and using the scale-invariant feature transform (SIFT) for feature registration on the selected sub-aperture images. Structure from motion (SFM) algorithm is further used on the registration completed sub-aperture images to reconstruct the three-dimensional scene. 3D sparse point cloud was obtained in the end. The method shows that the 3D reconstruction can be implemented by only two light field camera captures, rather than at least a dozen times captures by traditional cameras. This can effectively solve the time-consuming, laborious issues for 3D reconstruction based on traditional digital cameras, to achieve a more rapid, convenient and accurate reconstruction.

Time-of-flight PET image reconstruction using origin ensembles

Science.gov (United States)

Wülker, Christian; Sitek, Arkadiusz; Prevrhal, Sven

2015-03-01

The origin ensemble (OE) algorithm is a novel statistical method for minimum-mean-square-error (MMSE) reconstruction of emission tomography data. This method allows one to perform reconstruction entirely in the image domain, i.e. without the use of forward and backprojection operations. We have investigated the OE algorithm in the context of list-mode (LM) time-of-flight (TOF) PET reconstruction. In this paper, we provide a general introduction to MMSE reconstruction, and a statistically rigorous derivation of the OE algorithm. We show how to efficiently incorporate TOF information into the reconstruction process, and how to correct for random coincidences and scattered events. To examine the feasibility of LM-TOF MMSE reconstruction with the OE algorithm, we applied MMSE-OE and standard maximum-likelihood expectation-maximization (ML-EM) reconstruction to LM-TOF phantom data with a count number typically registered in clinical PET examinations. We analyzed the convergence behavior of the OE algorithm, and compared reconstruction time and image quality to that of the EM algorithm. In summary, during the reconstruction process, MMSE-OE contrast recovery (CRV) remained approximately the same, while background variability (BV) gradually decreased with an increasing number of OE iterations. The final MMSE-OE images exhibited lower BV and a slightly lower CRV than the corresponding ML-EM images. The reconstruction time of the OE algorithm was approximately 1.3 times longer. At the same time, the OE algorithm can inherently provide a comprehensive statistical characterization of the acquired data. This characterization can be utilized for further data processing, e.g. in kinetic analysis and image registration, making the OE algorithm a promising approach in a variety of applications.

DIEP Flap Breast Reconstruction in Patients with Breast Ptosis: 2-Stage Reconstruction Using 3-Dimensional Surface Imaging and a Printed Mold

Directory of Open Access Journals (Sweden)

Koichi Tomita, MD, PhD

2017-10-01

Conclusions:. The method described here may allow even inexperienced surgeons to achieve reconstruction of symmetrical, non-ptotic breasts with ease and in a short time. While the requirement of two surgeries is a potential disadvantage, our method will be particularly useful in cases involving TEs, i.e., delayed reconstruction or immediate reconstruction involving significant skin resection.

Low dose reconstruction algorithm for differential phase contrast imaging.

Science.gov (United States)

Wang, Zhentian; Huang, Zhifeng; Zhang, Li; Chen, Zhiqiang; Kang, Kejun; Yin, Hongxia; Wang, Zhenchang; Marco, Stampanoni

2011-01-01

Differential phase contrast imaging computed tomography (DPCI-CT) is a novel x-ray inspection method to reconstruct the distribution of refraction index rather than the attenuation coefficient in weakly absorbing samples. In this paper, we propose an iterative reconstruction algorithm for DPCI-CT which benefits from the new compressed sensing theory. We first realize a differential algebraic reconstruction technique (DART) by discretizing the projection process of the differential phase contrast imaging into a linear partial derivative matrix. In this way the compressed sensing reconstruction problem of DPCI reconstruction can be transformed to a resolved problem in the transmission imaging CT. Our algorithm has the potential to reconstruct the refraction index distribution of the sample from highly undersampled projection data. Thus it can significantly reduce the dose and inspection time. The proposed algorithm has been validated by numerical simulations and actual experiments.

Three-dimensional dictionary-learning reconstruction of (23)Na MRI data.

Science.gov (United States)

Behl, Nicolas G R; Gnahm, Christine; Bachert, Peter; Ladd, Mark E; Nagel, Armin M

2016-04-01

To reduce noise and artifacts in (23)Na MRI with a Compressed Sensing reconstruction and a learned dictionary as sparsifying transform. A three-dimensional dictionary-learning compressed sensing reconstruction algorithm (3D-DLCS) for the reconstruction of undersampled 3D radial (23)Na data is presented. The dictionary used as the sparsifying transform is learned with a K-singular-value-decomposition (K-SVD) algorithm. The reconstruction parameters are optimized on simulated data, and the quality of the reconstructions is assessed with peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). The performance of the algorithm is evaluated in phantom and in vivo (23)Na MRI data of seven volunteers and compared with nonuniform fast Fourier transform (NUFFT) and other Compressed Sensing reconstructions. The reconstructions of simulated data have maximal PSNR and SSIM for an undersampling factor (USF) of 10 with numbers of averages equal to the USF. For 10-fold undersampling, the PSNR is increased by 5.1 dB compared with the NUFFT reconstruction, and the SSIM by 24%. These results are confirmed by phantom and in vivo (23)Na measurements in the volunteers that show markedly reduced noise and undersampling artifacts in the case of 3D-DLCS reconstructions. The 3D-DLCS algorithm enables precise reconstruction of undersampled (23)Na MRI data with markedly reduced noise and artifact levels compared with NUFFT reconstruction. Small structures are well preserved. © 2015 Wiley Periodicals, Inc.

ELUCID—Exploring the Local Universe with the reConstructed Initial Density Field. II. Reconstruction Diagnostics, Applied to Numerical Halo Catalogs

Energy Technology Data Exchange (ETDEWEB)

Tweed, Dylan; Yang, Xiaohu; Li, Shijie; Jing, Y. P. [Center for Astronomy and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Huiyuan [Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China); Cui, Weiguang [Departamento de Física Teórica, Módulo 15, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Zhang, Youcai [Shanghai Astronomical Observatory, Nandan Road 80, Shanghai 200030 (China); Mo, H. J., E-mail: dtweed@sjtu.edu.cn [Department of Astronomy, University of Massachusetts, Amherst MA, 01003-9305 (United States)

2017-05-20

The ELUCID project aims to build a series of realistic cosmological simulations that reproduce the spatial and mass distributions of the galaxies as observed in the Sloan Digital Sky Survey. This requires powerful reconstruction techniques to create constrained initial conditions (ICs). We test the reconstruction method by applying it to several N -body simulations. We use two medium-resolution simulations, which each produced three additional constrained N -body simulations. We compare the resulting friend-of-friend catalogs by using the particle indexes as tracers, and quantify the quality of the reconstruction by varying the main smoothing parameter. The cross-identification method we use proves to be efficient, and the results suggest that the most massive reconstructed halos are effectively traced from the same Lagrangian regions in the ICs. A preliminary time-dependence analysis indicates that high-mass-end halos converge only at a redshift close to the reconstruction redshift. This suggests that, for earlier snapshots, only collections of progenitors may be effectively cross-identified.

Reconstruction of Chernobyl source parameters using gamma dose rate measurements in town Pripjat

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M. M. Talerko

2010-06-01

Full Text Available With the help of mathematical modeling of atmospheric transport the calculations of accidental release dispersion from the Chernobyl NPP to town Pripjat during period from 26 till 29 April 1986 have been carried out. Data of gamma rate measurements which was made in 31 points of the town were used. Based on the solution of atmospheric transport inverse problem the reconstruction of Chernobyl source parameters has been made including release intensity and effective source height. The input of main dose-forming radionuclides into the exposure dose during the first 40 hours after the accident (the period of population residence in the town before the evacuation has been estimated. According to the calculations the 131I deposition density averaged over the town territory was about 5.2 × 104 kBq/m2 (on 29.04.86. Minimum and maximum 131I deposition values were 2.8 × 104 kBq/m2 (western part, distance to the unit is 4.5 km and 1.2 × 105 kBq/m2 (north-eastern part of town, 2 km from the unit accordingly. For the moment of the evacuation dated April 27, deposition values were about 90 percent of these values.

European bank for reconstruction and development

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Kastratović Radovan

2015-01-01

Full Text Available European Bank for Reconstruction and Development - EBRD was established in the year 1991 and commenced operations in 1991. The objective of the Bank was to instigate market oriented approach to business in the countries of Central and Eastern Europe. This comprises support offered to structural reforms, privatisation, and development of entrepreneurship and legal system through financing of project conducive to the achievement of the aimed targets. The Bank approves loans both to the nation states and to the private sector. European Bank for Reconstruction and Development often appears in the role of investor. In addition, the Bank has also its consultative function. Owners of the European Bank for Reconstruction and Development are the developed countries and those that participate in the distribution of the Bank's profit. The Bank invests in the countries of Central, Eastern and South-East Europe, but also in those of Central Asia and Southern Mediterranean. The importance that the European Bank for Reconstruction and Development has for our country is best illustrated by the fact that this Bank is our largest institutional investor, with investments exceeding 3.5 billion EUR. This work begins with presentation of general information on the work of the European Bank for Reconstruction and Development, its objectives, activities, background history, ownership and organisational structure. It proceeds by giving relevant data on the Bank's business operations - the manner of project financing, the Bank's funds distribution per geographic criteria and activities, and the operative and financial results of the Bank's business activities. Brief description is also offered of the cooperation that the European Bank has with other international financial institutions. Finally, data is given bearing witness on the importance that the European Bank for Reconstruction and Development has for Serbia.

Improved immediate breast reconstruction as a result of oncoplastic multidisciplinary meeting

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El Gammal MM

2017-04-01

Full Text Available Mohsen M El Gammal,1 Maria Lim,1 Rajan Uppal,2 Richard Sainsbury1 1Department of Breast Surgery, Parapet Breast Centre, Frimley Health Foundation Trust, Windsor, 2Department of Plastic and Reconstructive Surgery, Wexham and Heatherwood Hospital, Frimley Health Foundation Trust, Slough, UK Introduction: The National Institute for Health and Clinical Excellence guidelines recommend that breast reconstruction should be available to all women undergoing mastectomy and discussed at the initial surgical consultation (2002, and updated 2009. The National Mastectomy and Breast Reconstruction Audit (2009 showed that 21% of mastectomy patients underwent immediate breast reconstruction (IBR and 11% had delayed breast reconstruction (DBR. Breast reconstruction has been shown to have a positive effect on quality of life postmastectomy. This retrospective study investigated the impact of the introduction of a dedicated oncoplastic multidisciplinary meeting (OP MDM on our unit’s breast reconstruction rate.Patients and methods: A retrospective analysis of 229 women who underwent mastectomy, of whom 81 (35% underwent breast reconstruction between April 2014 and March 2016. Data were analyzed before and after introduction of OP MDM in April 2015. Data on patient age, type of surgery (mastectomy only, mastectomy and reconstruction, timing of reconstruction (IBR, DBR, and type of reconstruction (implant, autologous were collected.Results: Between April 2015 and March 2016, following establishment of OP multidisciplinary team in April 2015, of the 120 patients who had mastectomy, 50 (42% underwent breast reconstruction with 78% (39/50 choosing IBR (56% implant reconstruction and 22% autologous. Compared to the period between April 2014 and March 2015 preceding the OP MDM, of 109 patients who underwent mastectomy, only 31 (28% had breast reconstruction with 64% (20/31 choosing IBR (45% implant reconstruction and 19% autologous. The rate of DBR was lower, 22% (11

Mandibular reconstruction using bone allografts

International Nuclear Information System (INIS)

Chang Joon Yim

1999-01-01

Further understanding of bone healing mechanisms, bone physiology and bone biology, transplantation immunology, and development of Tissue Banking procedures has enabled oral and maxillofacial surgeons to reconstruct even the most difficult bony defects successfully with the preserved allogeneic bone implant. Although it had been known that bone allografts were clinically effective, its application has not been widespread until the reports of Inclan (I 942), Hyatt and Butler (I 950), and Wilson (I 95 1). Tissue Banking provides the surgeon with a readily available, relatively inexpensive, and relatively safe selection of allogeneic bone for clinical use. Now autogenous bone and allogeneic bone implants present a wide variety of surgical options to surgeons, whether used separately or in combination. The surgeons are able to make judicious and fruitful choices, only with a thorough knowledge of the above-mentioned biological principles and skillful techniques. Many kinds of bone grafting techniques have been tried for reconstructing defective osseous tissues of the oral and maxillofacial region, though they have varying degrees of success. The osseous defects which require grafting include those of various size, shape, position, or amount. Unlike autogenous grafts, whose function is to provide osteogenic cells, allografts are purely passive, offering only a matrix for the inductive phase of bone healing. The condition of the recipient bed is of primary importance, because the host must produce all of the essential elements for the bone allograft to become incorporated. Depending on the processing methods of the allogeneic bone, the bone graft materials have different qualities, different healing potentials and different indications. Proper selection of grafts and surgical techniques requires an understanding of graft immunology and the mechanisms of graft healing. The surgeons should know about the biological principles to raise the clinical success rate

Apparatus and method for reconstructing data

International Nuclear Information System (INIS)

Pavkovich, J.M.

1977-01-01

The apparatus and method for reconstructing data are described. A fan beam of radiation is passed through an object, the beam lying in the same quasi-plane as the object slice to be examined. Radiation not absorbed in the object slice is recorded on oppositely situated detectors aligned with the source of radiation. Relative rotation is provided between the source-detector configuration and the object. Reconstruction means are coupled to the detector means, and may comprise a general purpose computer, a special purpose computer, and control logic for interfacing between said computers and controlling the respective functioning thereof for performing a convolution and back projection based upon non-absorbed radiation detected by said detector means, whereby the reconstruction means converts values of the non-absorbed radiation into values of absorbed radiation at each of an arbitrarily large number of points selected within the object slice. Display means are coupled to the reconstruction means for providing a visual or other display or representation of the quantities of radiation absorbed at the points considered in the object. (Auth.)

An iterative reconstruction from truncated projection data

International Nuclear Information System (INIS)

Anon.

1985-01-01

Various methods have been proposed for tomographic reconstruction from truncated projection data. In this paper, a reconstructive method is discussed which consists of iterations of filtered back-projection, reprojection and some nonlinear processings. First, the method is so constructed that it converges to a fixed point. Then, to examine its effectiveness, comparisons are made by computer experiments with two existing reconstructive methods for truncated projection data, that is, the method of extrapolation based on the smooth assumption followed by filtered back-projection, and modified additive ART

Parameters used in the environmental pathways (DESCARTES) and radiological dose (CIDER) modules of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC) for the air pathway

Energy Technology Data Exchange (ETDEWEB)

Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

1992-09-01

This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site since 1944. This work is being done by staff at Battelle, Pacific Northwest Laboratories (Battelle) under a contract with the Centers for Disease Control (CDC) with technical direction provided by an independent Technical Steering Panel (TSP). The objective of this report is to-document the environmental accumulation and dose-assessment parameters that will be used to estimate the impacts of past Hanford Site airborne releases. During 1993, dose estimates made by staff at Battelle will be used by the Fred Hutchinson Cancer Research Center as part of the Hanford Thyroid Disease Study (HTDS). This document contains information on parameters that are specific to the airborne release of the radionuclide iodine-131. Future versions of this document will include parameter information pertinent to other pathways and radionuclides.

Parameters used in the environmental pathways (DESCARTES) and radiological dose (CIDER) modules of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC) for the air pathway

International Nuclear Information System (INIS)

Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

1992-09-01

This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site since 1944. This work is being done by staff at Battelle, Pacific Northwest Laboratories (Battelle) under a contract with the Centers for Disease Control (CDC) with technical direction provided by an independent Technical Steering Panel (TSP). The objective of this report is to-document the environmental accumulation and dose-assessment parameters that will be used to estimate the impacts of past Hanford Site airborne releases. During 1993, dose estimates made by staff at Battelle will be used by the Fred Hutchinson Cancer Research Center as part of the Hanford Thyroid Disease Study (HTDS). This document contains information on parameters that are specific to the airborne release of the radionuclide iodine-131. Future versions of this document will include parameter information pertinent to other pathways and radionuclides

Genital reconstruction in exstrophy patients

Directory of Open Access Journals (Sweden)

R B Nerli

2012-01-01

Full Text Available Introduction: Surgery for bladder exstrophy has been evolving over the last four to five decades. Because survival has become almost universal, the focus has changed in the exstrophy-epispadias complex to improving quality of life. The most prevalent problem in the long-term function of exstrophy patients is the sexual activity of the adolescent and adult males. The penis in exstrophy patients appears short because of marked congenital deficiency of anterior corporal tissue. Many patients approach for genital reconstruction to improve cosmesis as well as to correct chordee. We report our series of male patients seeking genital reconstruction following exstrophy repair in the past. Materials and Methods: Fourteen adolescent/adult male patients attended urology services during the period January 2000-December 2009 seeking genital reconstruction following exstrophy repair in the past. Results: Three patients underwent epispadias repair, four patients had chordee correction with cosmetic excision of skin tags and seven patients underwent chordee correction with penile lengthening. All patients reported satisfaction in the answered questionnaire. Patients undergoing penile lengthening by partial corporal dissection achieved a mean increase in length of 1.614 ± 0.279 cm dorsally and 1.543 ± 0.230 cm ventrally. The satisfactory rate assessed by the Short Form-36 (SF-36 showed that irrespective of the different genital reconstructive procedures done, the patients were satisfied with cosmetic and functional outcome. Conclusions: Surgical procedures have transformed the management in these patients with bladder exstrophy. Bladders can be safely placed within the pelvis, with most patients achieving urinary continence and cosmetically acceptable external genitalia. Genital reconstruction in the form of correction of chordee, excision of ugly skin tags and lengthening of penis can be performed to give the patients a satisfactory cosmetic and functional

Parameters used in the environmental pathways and radiological dose modules (DESCARTES, CIDER, and CRD codes) of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC)

International Nuclear Information System (INIS)

Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

1994-05-01

This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site during the period of 1944 to 1992. This work is being done by staff at Battelle, Pacific Northwest Laboratories under a contract with the Centers for Disease Control and Prevention with technical direction provided by an independent Technical Steering Panel (TSP)

Parameters used in the environmental pathways and radiological dose modules (DESCARTES, CIDER, and CRD codes) of the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC)

Energy Technology Data Exchange (ETDEWEB)

Snyder, S.F.; Farris, W.T.; Napier, B.A.; Ikenberry, T.A.; Gilbert, R.O.

1994-05-01

This letter report is a description of work performed for the Hanford Environmental Dose Reconstruction (HEDR) Project. The HEDR Project was established to estimate the radiation doses to individuals resulting from releases of radionuclides from the Hanford Site during the period of 1944 to 1992. This work is being done by staff at Battelle, Pacific Northwest Laboratories under a contract with the Centers for Disease Control and Prevention with technical direction provided by an independent Technical Steering Panel (TSP).

Reconstruction of the Proximal Humerus after Wide Resection of Tumors: Comparison of Three Reconstructive Options

International Nuclear Information System (INIS)

EL-SHERBINY, M.

2008-01-01

Purpose: Assessment of the functional results and complications of three bone reconstructive procedures after resection of primary tumors of the proximal humerus. Material and Methods: Between 2000 and 2008, 32 patients having primary malignant, aggressive benign or metastatic tumors of the proximal humerous were selected for limb sparing surgery. Preoperative evaluation included CT chest, MRI. Limb sparing surgical resection was done including intraarticular or extra articular wide resection of the tumor. Bone defect was reconstructed with fusion shoulder using free vascularized fibular graft (FFFG) in 11 patients and pedicled lateral scapular crest graft (PLSCG) in 8 patients and mobile shoulder reconstruction using proximal humerus prosthesis in 13 patients. Those patients were followed-up at regular interval to detect bone union and complications related to bone flaps or prosthesis. Functional results were assessed for every patient after one year postoperatively. Results: The median age of the patients was 21 years and the follow-up period ranged from 19 months to 92 months. Postoperative resection margins were negative in all cases. The mean length of the resected humerus was 13 cm. The mean operative time for prosthesis cases was 3.5 hours and that for FVFG was 6.5 hours and was 5 hours for PLSCG cases. The mean time of bone union proximally and distally for FVFG and PLSCG was 4.2 and 5.5 months accordingly. At 1 year follow-up, the functional results for the three reconstructive procedures were nearly the same with a mean functional score for FVFG cases was 73%, for PLSCG cases was 68% and was 71% for prosthesis cases. Hand and elbow functions were preserved in all types of reconstruction. The range of shoulder abduction and flexion was grossly limited with prosthesis cases while it showed marked improvement with fusion by FVFG and PLSCG. Complications for prosthesis cases were one case proximal migration and one case posterior sublaxation. Complications of

Reconstruction of 3D PIV data in complicated experimental arrangements

Directory of Open Access Journals (Sweden)

Pavlík David

2017-01-01

Full Text Available In this paper a three-dimensional reconstruction of flow field behind flat plate representing a wing is presented. The reconstruction is always performed for pair of 2D vector maps obtained by 3D PIV with two cameras which record measurement area from different locations. Three-dimensional reconstruction can be obtained in various ways. This paper summarizes two: the reconstruction based on the known correspondences and the reconstruction based on the knowledge of intrinsic and extrinsic parameters of cameras. The methods can be used in the cases when it is impossible to use a calibration pattern or when reconstruction by commercial software fails.

Super-Resolution Image Reconstruction Applied to Medical Ultrasound

Science.gov (United States)

Ellis, Michael

Ultrasound is the preferred imaging modality for many diagnostic applications due to its real-time image reconstruction and low cost. Nonetheless, conventional ultrasound is not used in many applications because of limited spatial resolution and soft tissue contrast. Most commercial ultrasound systems reconstruct images using a simple delay-and-sum architecture on receive, which is fast and robust but does not utilize all information available in the raw data. Recently, more sophisticated image reconstruction methods have been developed that make use of far more information in the raw data to improve resolution and contrast. One such method is the Time-Domain Optimized Near-Field Estimator (TONE), which employs a maximum a priori estimation to solve a highly underdetermined problem, given a well-defined system model. TONE has been shown to significantly improve both the contrast and resolution of ultrasound images when compared to conventional methods. However, TONE's lack of robustness to variations from the system model and extremely high computational cost hinder it from being readily adopted in clinical scanners. This dissertation aims to reduce the impact of TONE's shortcomings, transforming it from an academic construct to a clinically viable image reconstruction algorithm. By altering the system model from a collection of individual hypothetical scatterers to a collection of weighted, diffuse regions, dTONE is able to achieve much greater robustness to modeling errors. A method for efficient parallelization of dTONE is presented that reduces reconstruction time by more than an order of magnitude with little loss in image fidelity. An alternative reconstruction algorithm, called qTONE, is also developed and is able to reduce reconstruction times by another two orders of magnitude while simultaneously improving image contrast. Each of these methods for improving TONE are presented, their limitations are explored, and all are used in concert to reconstruct in

[Pedicled versus free TRAM flap for breast reconstruction].

Science.gov (United States)

Galla, T J; Lukas, B; Feller, A M

1999-03-01

In breast reconstruction, the free TRAM-flap offers many advantages over the pedicled TRAM-flap. Due to its superior perfusion, the free flap rarely develops necrosis. Shaping of the flap is easier due to the lack of the thick muscle pedicle. Because the rectus muscle is spared, there is minimal donor site morbidity. However, the necessary microvascular anastomoses reduced the acceptance of the free TRAM-flap. During a 13-months period, 51 breast reconstructions were performed in 41 patients, 31 unilateral and ten bilateral. 45 flaps served for delayed reconstruction and six flaps for immediate reconstruction. The operations were performed by two teams working simultaneously. The average operating time was 3.9 hours for unilateral and 6.9 hours for bilateral delayed reconstruction. For immediate reconstruction, 6.2 and 6.3 hours were required for uni- and bilateral procedures, respectively. In 38 flaps, the thoracodorsal vessels served as recipient vessels; 13 flaps were anastomosed to the internal mammary artery and vein. Postoperative complications were observed in 13 patients. Three vessel anastomoses had to be revised. In one flap, a partial necrosis occurred; in two flaps hematoma evacuation was necessary. Two patients suffered from fat necroses at the abdomen and one umbilicus was lost. Skin irritations and seromas at the abdomen occurred in five patients. Pulmonary embolism was diagnosed in one patient three weeks postoperatively. Abdominal hernias or bulging in the epigastric area were not observed up to 15 months after reconstruction. These results reveal a low complication rate for breast reconstruction with the free TRAM-flap. The advantages of this technique as compared to the pedicled technique are discussed.

A fast sparse reconstruction algorithm for electrical tomography

International Nuclear Information System (INIS)

Zhao, Jia; Xu, Yanbin; Tan, Chao; Dong, Feng

2014-01-01

Electrical tomography (ET) has been widely investigated due to its advantages of being non-radiative, low-cost and high-speed. However, the image reconstruction of ET is a nonlinear and ill-posed inverse problem and the imaging results are easily affected by measurement noise. A sparse reconstruction algorithm based on L 1 regularization is robust to noise and consequently provides a high quality of reconstructed images. In this paper, a sparse reconstruction by separable approximation algorithm (SpaRSA) is extended to solve the ET inverse problem. The algorithm is competitive with the fastest state-of-the-art algorithms in solving the standard L 2 −L 1 problem. However, it is computationally expensive when the dimension of the matrix is large. To further improve the calculation speed of solving inverse problems, a projection method based on the Krylov subspace is employed and combined with the SpaRSA algorithm. The proposed algorithm is tested with image reconstruction of electrical resistance tomography (ERT). Both simulation and experimental results demonstrate that the proposed method can reduce the computational time and improve the noise robustness for the image reconstruction. (paper)

A new method of morphological comparison for bony reconstructive surgery: maxillary reconstruction using scapular tip bone

Science.gov (United States)

Chan, Harley; Gilbert, Ralph W.; Pagedar, Nitin A.; Daly, Michael J.; Irish, Jonathan C.; Siewerdsen, Jeffrey H.

2010-02-01

esthetic appearance is one of the most important factors for reconstructive surgery. The current practice of maxillary reconstruction chooses radial forearm, fibula or iliac rest osteocutaneous to recreate three-dimensional complex structures of the palate and maxilla. However, these bone flaps lack shape similarity to the palate and result in a less satisfactory esthetic. Considering similarity factors and vasculature advantages, reconstructive surgeons recently explored the use of scapular tip myo-osseous free flaps to restore the excised site. We have developed a new method that quantitatively evaluates the morphological similarity of the scapula tip bone and palate based on a diagnostic volumetric computed tomography (CT) image. This quantitative result was further interpreted as a color map that rendered on the surface of a three-dimensional computer model. For surgical planning, this color interpretation could potentially assist the surgeon to maximize the orientation of the bone flaps for best fit of the reconstruction site. With approval from the Research Ethics Board (REB) of the University Health Network, we conducted a retrospective analysis with CT image obtained from 10 patients. Each patient had a CT scans including the maxilla and chest on the same day. Based on this image set, we simulated total, subtotal and hemi palate reconstruction. The procedure of simulation included volume segmentation, conversing the segmented volume to a stereo lithography (STL) model, manual registration, computation of minimum geometric distances and curvature between STL model. Across the 10 patients data, we found the overall root-mean-square (RMS) conformance was 3.71+/- 0.16 mm

[Reconstruction of the ear in the burns patient].

Science.gov (United States)

Carrillo-Córdova, Jorge Raúl; Jiménez Murat, Yusef; Apellaniz-Campo, Armando; Bracho-Olvera, Hazel; Carrillo Esper, Raúl

Face burns are a singular pathology with great functional and psychological impact in the patients suffering them. The ears play a fundamental role in personal interactions and damage to this organ results in physical and emotional distress. The reconstructive treatment of the burned ear is a challenge. Multiple procedures have been described to achieve success in the reconstruction of the burned ear; immediate reconstruction with autologous rib cartilage, secondary reconstruction, alloplastic material reconstruction, tissue expansion, skin grafts and also microvascular flaps are some of the most common procedures used in this patients. All these techniques focus on giving a natural appearance to the patient. Burns to the ears affect 30% of the patients with facial burns, they require an excellent treatment given by a multidisciplinary team. Copyright © 2017 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Direct iterative reconstruction of computed tomography trajectories (DIRECTT)

International Nuclear Information System (INIS)

Lange, A.; Hentschel, M.P.; Schors, J.

2004-01-01

The direct reconstruction approach employs an iterative procedure by selection of and angular averaging over projected trajectory data of volume elements. This avoids the blur effects of the classical Fourier method due to the sampling theorem. But longer computing time is required. The reconstructed tomographic images reveal at least the spatial resolution of the radiation detector. Any set of projection angles may be selected for the measurements. Limited rotation of the object yields still good reconstruction of details. Projections of a partial region of the object can be reconstructed without additional artifacts thus reducing the overall radiation dose. Noisy signal data from low dose irradiation have low impact on spatial resolution. The image quality is monitored during all iteration steps and is pre-selected according to the specific requirements. DIRECTT can be applied independently from the measurement equipment in addition to conventional reconstruction or as a refinement filter. (author)

Wind reconstruction algorithm for Viking Lander 1

Science.gov (United States)

Kynkäänniemi, Tuomas; Kemppinen, Osku; Harri, Ari-Matti; Schmidt, Walter

2017-06-01

The wind measurement sensors of Viking Lander 1 (VL1) were only fully operational for the first 45 sols of the mission. We have developed an algorithm for reconstructing the wind measurement data after the wind measurement sensor failures. The algorithm for wind reconstruction enables the processing of wind data during the complete VL1 mission. The heater element of the quadrant sensor, which provided auxiliary measurement for wind direction, failed during the 45th sol of the VL1 mission. Additionally, one of the wind sensors of VL1 broke down during sol 378. Regardless of the failures, it was still possible to reconstruct the wind measurement data, because the failed components of the sensors did not prevent the determination of the wind direction and speed, as some of the components of the wind measurement setup remained intact for the complete mission. This article concentrates on presenting the wind reconstruction algorithm and methods for validating the operation of the algorithm. The algorithm enables the reconstruction of wind measurements for the complete VL1 mission. The amount of available sols is extended from 350 to 2245 sols.

Wind reconstruction algorithm for Viking Lander 1

Directory of Open Access Journals (Sweden)

T. Kynkäänniemi

2017-06-01

Full Text Available The wind measurement sensors of Viking Lander 1 (VL1 were only fully operational for the first 45 sols of the mission. We have developed an algorithm for reconstructing the wind measurement data after the wind measurement sensor failures. The algorithm for wind reconstruction enables the processing of wind data during the complete VL1 mission. The heater element of the quadrant sensor, which provided auxiliary measurement for wind direction, failed during the 45th sol of the VL1 mission. Additionally, one of the wind sensors of VL1 broke down during sol 378. Regardless of the failures, it was still possible to reconstruct the wind measurement data, because the failed components of the sensors did not prevent the determination of the wind direction and speed, as some of the components of the wind measurement setup remained intact for the complete mission. This article concentrates on presenting the wind reconstruction algorithm and methods for validating the operation of the algorithm. The algorithm enables the reconstruction of wind measurements for the complete VL1 mission. The amount of available sols is extended from 350 to 2245 sols.

Radiotherapy and breast reconstruction: a meta-analysis.

LENUS (Irish Health Repository)

Barry, M

2011-05-01

The optimum sequencing of breast reconstruction (BR) in patients receiving postmastectomy radiation therapy (PMRT) is controversial. A comprehensive search of published studies that examined postoperative morbidity following immediate or delayed BR with combined radiotherapy was performed. Medical (MEDLINE & EMBASE) databases were searched and cross-referenced for appropriate studies where morbidity following BR was the primary outcome measured. A total of 1,105 patients were identified from 11 appropriately selected studies. Patients undergoing PMRT and BR are more likely to suffer morbidity compared with patients not receiving PMRT (OR = 4.2; 95% CI, 2.4-7.2 [no PMRT vs. PMRT]). Reconstruction technique was also examined with outcome when PMRT was delivered after BR, and this demonstrated that autologous reconstruction is associated with less morbidity in this setting (OR = 0.21; 95% CI, 0.1-0.4 [autologous vs. implant-based]). Delaying BR until after PMRT had no significant effect on outcome (OR = 0.87; 95% CI, 0.47-1.62 [delayed vs. immediate]). PMRT has a detrimental effect on BR outcome. These results suggest that where immediate reconstruction is undertaken with the necessity of PMRT, an autologous flap results in less morbidity when compared with implant-based reconstruction.

Confidence and sensitivity of sea-level reconstructions

DEFF Research Database (Denmark)

Svendsen, Peter Limkilde

For the last two decades, satellite altimetry has provided a near-global view of spatial and temporal patterns in sea surface height (SSH). When combined with records from tide gauges, a historical reconstruction of sea level can be obtained; while tide gauge records span up to 200 years back...... nature of the data fields. We examine the sensitivity of a reconstruction with respect to the length of calibration time series, and the spatial distribution of tide gauges or other proxy data. In addition, we consider the eect of isolating certain physical phenomena (e.g. ENSO) and annual signals...... and modelling these outside the reconstruction. The implementation is currently based on data from compound satellite datasets (i.e., two decades of altimetry), and the Simple Ocean Data Assimilation (SODA) model, an existing reconstruction, where a calibration period can be easily extracted and our model...

Reconstruction of Clear-PEM data with STIR

CERN Document Server

Martins, M V; Rodrigues, P; Trindade, A; Oliveira, N; Correia, M; Cordeiro, H; Ferreira, N C; Varela, J; Almeida, P

2006-01-01

The Clear-PEM scanner is a device based on planar detectors that is currently under development within the Crystal Clear Collaboration, at CERN. The basis for 3D image reconstruction in Clear-PEM is the software for tomographic image reconstruction (STIR). STIR is an open source object-oriented library that efficiently deals with the 3D positron emission tomography data sets. This library was originally designed for the traditional cylindrical scanners. In order to make its use compatible with planar scanner data, new functionalities were introduced into the library's framework. In this work, Monte Carlo simulations of the Clear-PEM scanner acquisitions were used as input for image reconstruction with the 3D OSEM algorithm available in STIR. The results presented indicate that dual plate PEM data can be accurately reconstructed using the enhanced STIR framework.

Discrete Wigner Function Reconstruction and Compressed Sensing

OpenAIRE

Zhang, Jia-Ning; Fang, Lei; Ge, Mo-Lin

2011-01-01

A new reconstruction method for Wigner function is reported for quantum tomography based on compressed sensing. By analogy with computed tomography, Wigner functions for some quantum states can be reconstructed with less measurements utilizing this compressed sensing based method.

Three-dimensional reconstruction and visualization system for medical images

International Nuclear Information System (INIS)

Preston, D.F.; Batnitzky, S.; Kyo Rak Lee; Cook, P.N.; Cook, L.T.; Dwyer, S.J.

1982-01-01

A three-dimensional reconstruction and visualization system could be of significant advantage in medical application such as neurosurgery and radiation treatment planning. The reconstructed anatomic structures from CT head scans could be used in a head stereotactic system to help plan the surgical procedure and the radiation treatment for a brain lesion. Also, the use of three-dimensional reconstruction algorithm provides for quantitative measures such as volume and surface area estimation of the anatomic features. This aspect of the three-dimensional reconstruction system may be used to monitor the progress or staging of a disease and the effects of patient treatment. Two cases are presented to illustrate the three-dimensional surface reconstruction and visualization system

Monthly paleostreamflow reconstruction from annual tree-ring chronologies

Science.gov (United States)

Stagge, J. H.; Rosenberg, D. E.; DeRose, R. J.; Rittenour, T. M.

2018-02-01

Paleoclimate reconstructions are increasingly used to characterize annual climate variability prior to the instrumental record, to improve estimates of climate extremes, and to provide a baseline for climate-change projections. To date, paleoclimate records have seen limited engineering use to estimate hydrologic risks because water systems models and managers usually require streamflow input at the monthly scale. This study explores the hypothesis that monthly streamflows can be adequately modeled by statistically decomposing annual flow reconstructions. To test this hypothesis, a multiple linear regression model for monthly streamflow reconstruction is presented that expands the set of predictors to include annual streamflow reconstructions, reconstructions of global circulation, and potential differences among regional tree-ring chronologies related to tree species and geographic location. This approach is used to reconstruct 600 years of monthly streamflows at two sites on the Bear and Logan rivers in northern Utah. Nash-Sutcliffe Efficiencies remain above zero (0.26-0.60) for all months except April and Pearson's correlation coefficients (R) are 0.94 and 0.88 for the Bear and Logan rivers, respectively, confirming that the model can adequately reproduce monthly flows during the reference period (10/1942 to 9/2015). Incorporating a flexible transition between the previous and concurrent annual reconstructed flows was the most important factor for model skill. Expanding the model to include global climate indices and regional tree-ring chronologies produced smaller, but still significant improvements in model fit. The model presented here is the only approach currently available to reconstruct monthly streamflows directly from tree-ring chronologies and climate reconstructions, rather than using resampling of the observed record. With reasonable estimates of monthly flow that extend back in time many centuries, water managers can challenge systems models with a

Iterative CT reconstruction via minimizing adaptively reweighted total variation.

Science.gov (United States)

Zhu, Lei; Niu, Tianye; Petrongolo, Michael

2014-01-01

Iterative reconstruction via total variation (TV) minimization has demonstrated great successes in accurate CT imaging from under-sampled projections. When projections are further reduced, over-smoothing artifacts appear in the current reconstruction especially around the structure boundaries. We propose a practical algorithm to improve TV-minimization based CT reconstruction on very few projection data. Based on the theory of compressed sensing, the L-0 norm approach is more desirable to further reduce the projection views. To overcome the computational difficulty of the non-convex optimization of the L-0 norm, we implement an adaptive weighting scheme to approximate the solution via a series of TV minimizations for practical use in CT reconstruction. The weight on TV is initialized as uniform ones, and is automatically changed based on the gradient of the reconstructed image from the previous iteration. The iteration stops when a small difference between the weighted TV values is observed on two consecutive reconstructed images. We evaluate the proposed algorithm on both a digital phantom and a physical phantom. Using 20 equiangular projections, our method reduces reconstruction errors in the conventional TV minimization by a factor of more than 5, with improved spatial resolution. By adaptively reweighting TV in iterative CT reconstruction, we successfully further reduce the projection number for the same or better image quality.

The North American Drought Atlas: Tree-Ring Reconstructions of Drought Variability for Climate Modeling and Assessment

Science.gov (United States)

Cook, E. R.

2007-05-01

The North American Drought Atlas describes a detailed reconstruction of drought variability from tree rings over most of North America for the past 500-1000 years. The first version of it, produced over three years ago, was based on a network of 835 tree-ring chronologies and a 286-point grid of instrumental Palmer Drought Severity Indices (PDSI). These gridded PDSI reconstructions have been used in numerous published studies now that range from modeling fire in the American West, to the impact of drought on palaeo-Indian societies, and to the determination of the primary causes of drought over North America through climate modeling experiments. Some examples of these applications will be described to illustrate the scientific value of these large-scale reconstructions of drought. Since the development and free public release of Version 1 of the North American Drought Atlas (see http:iridl.ldeo.columbia.edu/SOURCES/.LDEO/.TRL/.NADA2004/.pdsi-atlas.html), great improvements have been made in the critical tree-ring network used to reconstruct PDSI at each grid point. This network has now been enlarged to 1743 annual tree-ring chronologies, which greatly improves the density of tree-ring records in certain parts of the grid, especially in Canada and Mexico. In addition, the number of tree-ring records that extend back before AD 1400 has been substantially increased. These developments justify the creation of Version 2 of the North American Drought Atlas. In this talk I will describe this new version of the drought atlas and some of its properties that make it a significant improvement over the previous version. The new product provides enhanced resolution of the spatial and temporal variability of prolonged drought such as the late 16th century event that impacted regions of both Mexico and the United States. I will also argue for the North American Drought Atlas being used as a template for the development of large-scale drought reconstructions in other land areas of

Perforator based rectus free tissue transfer for head and neck reconstruction: New reconstructive advantages from an old friend.

Science.gov (United States)

Kang, Stephen Y; Spector, Matthew E; Chepeha, Douglas B

2017-11-01

To demonstrate three reconstructive advantages of the perforator based rectus free tissue transfer: long pedicle, customizable adipose tissue, and volume reconstruction without muscle atrophy within a contained space. Thirty patients with defects of the head and neck were reconstructed with the perforator based rectus free tissue transfer. Transplant success was 93%. Mean pedicle length was 13.4cm. Eleven patients (37%) had vessel-poor necks and the long pedicle provided by this transplant avoided the need for vein grafts in these patients. Adipose tissue was molded in 17 patients (57%). Twenty-five patients (83%) had defects within a contained space, such as the orbit, where it was critical to have a transplant that avoided muscle atrophy. The perforator based rectus free tissue transfer provides a long pedicle, moldable fat for flap customization, and is useful in reconstruction of defects within a contained space where volume loss due to muscle atrophy is prevented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Seismic interferometry : Reconstructing the earth's reflection response

NARCIS (Netherlands)

Draganov, D.S.; Wapenaar, C.P.A.; Thorbecke, J.W.

2006-01-01

In 1968, Jon Claerbout showed that the reflection response of a 1D acoustic medium can be reconstructed by autocorrelating the transmission response. Since then, several authors have derived relationships for reconstructing Green's functions at the surface, using crosscorrelations of (noise)

Angular self-reconstruction of petal-like beams

CSIR Research Space (South Africa)

Litvin, IA

2013-09-01

Full Text Available equation for predicting the self-reconstruction distance of superpositions of LG beams, which we confirm by numerical propagation as well as by experiment. We explain that the self-reconstruction process is not guaranteed and predict its dependence...

Equilibrium Reconstruction in EAST Tokamak

International Nuclear Information System (INIS)

Qian Jinping; Wan Baonian; Shen Biao; Sun Youwen; Liu Dongmei; Xiao Bingjia; Ren Qilong; Gong Xianzu; Li Jiangang; Lao, L. L.; Sabbagh, S. A.

2009-01-01

Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier expansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign. (magnetically confined plasma)

[From the French Society of Plastic and Reconstructive Surgery to the French Society of Plastic Reconstructive and Aesthetic Surgery].

Science.gov (United States)

Glicenstein, J

2004-04-01

(The) 3rd December 1952, 11 surgeons and other specialists found the French Society of Plastic and Reconstructive Surgery (SFCPR) which was officially published on (the) 28 September 1953. The first congress was during October 1953 and the first president as Maurice Aubry. The first secretary was Daniel Morel Fatio. The symposiums were after about three of four times each year and the thematic subjects were initially according the reconstructive surgery. The review "Annales de chirurgie plastique" was free in 1956. The members of the Society were about 30 initially, but their plastic surgery in the big hospitals at Paris and other big towns in France. The "specialty" of plastic surgery was created in 1971. On "syndicate", one French board of plastic reconstructive and aesthetic surgery, the increasing of departments of plastic surgery were the front of increasing of the plastic surgery in French and of the number of the French Society of Plastic Reconstructive surgery (580 in 2003). The French Society organized the International Congress of Plastic Surgery in 1975. The society SFCPR became the French Society of plastic reconstruction and Aesthetic Surgery (SFCPRE) in 1983 and the "logo" (front view) was in the 1994 SOF.CPRE.

Evaluation of a 3D point cloud tetrahedral tomographic reconstruction method

Science.gov (United States)

Pereira, N. F.; Sitek, A.

2010-09-01

Tomographic reconstruction on an irregular grid may be superior to reconstruction on a regular grid. This is achieved through an appropriate choice of the image space model, the selection of an optimal set of points and the use of any available prior information during the reconstruction process. Accordingly, a number of reconstruction-related parameters must be optimized for best performance. In this work, a 3D point cloud tetrahedral mesh reconstruction method is evaluated for quantitative tasks. A linear image model is employed to obtain the reconstruction system matrix and five point generation strategies are studied. The evaluation is performed using the recovery coefficient, as well as voxel- and template-based estimates of bias and variance measures, computed over specific regions in the reconstructed image. A similar analysis is performed for regular grid reconstructions that use voxel basis functions. The maximum likelihood expectation maximization reconstruction algorithm is used. For the tetrahedral reconstructions, of the five point generation methods that are evaluated, three use image priors. For evaluation purposes, an object consisting of overlapping spheres with varying activity is simulated. The exact parallel projection data of this object are obtained analytically using a parallel projector, and multiple Poisson noise realizations of these exact data are generated and reconstructed using the different point generation strategies. The unconstrained nature of point placement in some of the irregular mesh-based reconstruction strategies has superior activity recovery for small, low-contrast image regions. The results show that, with an appropriately generated set of mesh points, the irregular grid reconstruction methods can out-perform reconstructions on a regular grid for mathematical phantoms, in terms of the performance measures evaluated.

Evaluation of a 3D point cloud tetrahedral tomographic reconstruction method

International Nuclear Information System (INIS)

Pereira, N F; Sitek, A

2010-01-01

Tomographic reconstruction on an irregular grid may be superior to reconstruction on a regular grid. This is achieved through an appropriate choice of the image space model, the selection of an optimal set of points and the use of any available prior information during the reconstruction process. Accordingly, a number of reconstruction-related parameters must be optimized for best performance. In this work, a 3D point cloud tetrahedral mesh reconstruction method is evaluated for quantitative tasks. A linear image model is employed to obtain the reconstruction system matrix and five point generation strategies are studied. The evaluation is performed using the recovery coefficient, as well as voxel- and template-based estimates of bias and variance measures, computed over specific regions in the reconstructed image. A similar analysis is performed for regular grid reconstructions that use voxel basis functions. The maximum likelihood expectation maximization reconstruction algorithm is used. For the tetrahedral reconstructions, of the five point generation methods that are evaluated, three use image priors. For evaluation purposes, an object consisting of overlapping spheres with varying activity is simulated. The exact parallel projection data of this object are obtained analytically using a parallel projector, and multiple Poisson noise realizations of these exact data are generated and reconstructed using the different point generation strategies. The unconstrained nature of point placement in some of the irregular mesh-based reconstruction strategies has superior activity recovery for small, low-contrast image regions. The results show that, with an appropriately generated set of mesh points, the irregular grid reconstruction methods can out-perform reconstructions on a regular grid for mathematical phantoms, in terms of the performance measures evaluated.

Evaluation of a 3D point cloud tetrahedral tomographic reconstruction method

Energy Technology Data Exchange (ETDEWEB)

Pereira, N F; Sitek, A, E-mail: nfp4@bwh.harvard.ed, E-mail: asitek@bwh.harvard.ed [Department of Radiology, Brigham and Women' s Hospital-Harvard Medical School Boston, MA (United States)

2010-09-21

Tomographic reconstruction on an irregular grid may be superior to reconstruction on a regular grid. This is achieved through an appropriate choice of the image space model, the selection of an optimal set of points and the use of any available prior information during the reconstruction process. Accordingly, a number of reconstruction-related parameters must be optimized for best performance. In this work, a 3D point cloud tetrahedral mesh reconstruction method is evaluated for quantitative tasks. A linear image model is employed to obtain the reconstruction system matrix and five point generation strategies are studied. The evaluation is performed using the recovery coefficient, as well as voxel- and template-based estimates of bias and variance measures, computed over specific regions in the reconstructed image. A similar analysis is performed for regular grid reconstructions that use voxel basis functions. The maximum likelihood expectation maximization reconstruction algorithm is used. For the tetrahedral reconstructions, of the five point generation methods that are evaluated, three use image priors. For evaluation purposes, an object consisting of overlapping spheres with varying activity is simulated. The exact parallel projection data of this object are obtained analytically using a parallel projector, and multiple Poisson noise realizations of these exact data are generated and reconstructed using the different point generation strategies. The unconstrained nature of point placement in some of the irregular mesh-based reconstruction strategies has superior activity recovery for small, low-contrast image regions. The results show that, with an appropriately generated set of mesh points, the irregular grid reconstruction methods can out-perform reconstructions on a regular grid for mathematical phantoms, in terms of the performance measures evaluated.

Penalized maximum likelihood reconstruction for x-ray differential phase-contrast tomography

International Nuclear Information System (INIS)

Brendel, Bernhard; Teuffenbach, Maximilian von; Noël, Peter B.; Pfeiffer, Franz; Koehler, Thomas

2016-01-01

Purpose: The purpose of this work is to propose a cost function with regularization to iteratively reconstruct attenuation, phase, and scatter images simultaneously from differential phase contrast (DPC) acquisitions, without the need of phase retrieval, and examine its properties. Furthermore this reconstruction method is applied to an acquisition pattern that is suitable for a DPC tomographic system with continuously rotating gantry (sliding window acquisition), overcoming the severe smearing in noniterative reconstruction. Methods: We derive a penalized maximum likelihood reconstruction algorithm to directly reconstruct attenuation, phase, and scatter image from the measured detector values of a DPC acquisition. The proposed penalty comprises, for each of the three images, an independent smoothing prior. Image quality of the proposed reconstruction is compared to images generated with FBP and iterative reconstruction after phase retrieval. Furthermore, the influence between the priors is analyzed. Finally, the proposed reconstruction algorithm is applied to experimental sliding window data acquired at a synchrotron and results are compared to reconstructions based on phase retrieval. Results: The results show that the proposed algorithm significantly increases image quality in comparison to reconstructions based on phase retrieval. No significant mutual influence between the proposed independent priors could be observed. Further it could be illustrated that the iterative reconstruction of a sliding window acquisition results in images with substantially reduced smearing artifacts. Conclusions: Although the proposed cost function is inherently nonconvex, it can be used to reconstruct images with less aliasing artifacts and less streak artifacts than reconstruction methods based on phase retrieval. Furthermore, the proposed method can be used to reconstruct images of sliding window acquisitions with negligible smearing artifacts

Detector independent cellular automaton algorithm for track reconstruction

Energy Technology Data Exchange (ETDEWEB)

Kisel, Ivan; Kulakov, Igor; Zyzak, Maksym [Goethe Univ. Frankfurt am Main (Germany); Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany); Collaboration: CBM-Collaboration

2013-07-01

Track reconstruction is one of the most challenging problems of data analysis in modern high energy physics (HEP) experiments, which have to process per second of the order of 10{sup 7} events with high track multiplicity and density, registered by detectors of different types and, in many cases, located in non-homogeneous magnetic field. Creation of reconstruction package common for all experiments is considered to be important in order to consolidate efforts. The cellular automaton (CA) track reconstruction approach has been used successfully in many HEP experiments. It is very simple, efficient, local and parallel. Meanwhile it is intrinsically independent of detector geometry and good candidate for common track reconstruction. The CA implementation for the CBM experiment has been generalized and applied to the ALICE ITS and STAR HFT detectors. Tests with simulated collisions have been performed. The track reconstruction efficiencies are at the level of 95% for majority of the signal tracks for all detectors.

Optimization of reconstruction algorithms using Monte Carlo simulation

International Nuclear Information System (INIS)

Hanson, K.M.

1989-01-01

A method for optimizing reconstruction algorithms is presented that is based on how well a specified task can be performed using the reconstructed images. Task performance is numerically assessed by a Monte Carlo simulation of the complete imaging process including the generation of scenes appropriate to the desired application, subsequent data taking, reconstruction, and performance of the stated task based on the final image. The use of this method is demonstrated through the optimization of the Algebraic Reconstruction Technique (ART), which reconstructs images from their projections by a iterative procedure. The optimization is accomplished by varying the relaxation factor employed in the updating procedure. In some of the imaging situations studied, it is found that the optimization of constrained ART, in which a nonnegativity constraint is invoked, can vastly increase the detectability of objects. There is little improvement attained for unconstrained ART. The general method presented may be applied to the problem of designing neutron-diffraction spectrometers. 11 refs., 6 figs., 2 tabs

Optimization of reconstruction algorithms using Monte Carlo simulation

International Nuclear Information System (INIS)

Hanson, K.M.

1989-01-01

A method for optimizing reconstruction algorithms is presented that is based on how well a specified task can be performed using the reconstructed images. Task performance is numerically assessed by a Monte Carlo simulation of the complete imaging process including the generation of scenes appropriate to the desired application, subsequent data taking, reconstruction, and performance of the stated task based on the final image. The use of this method is demonstrated through the optimization of the Algebraic Reconstruction Technique (ART), which reconstructs images from their projections by an iterative procedure. The optimization is accomplished by varying the relaxation factor employed in the updating procedure. In some of the imaging situations studied, it is found that the optimization of constrained ART, in which a non-negativity constraint is invoked, can vastly increase the detectability of objects. There is little improvement attained for unconstrained ART. The general method presented may be applied to the problem of designing neutron-diffraction spectrometers. (author)

Direct cone beam SPECT reconstruction with camera tilt

International Nuclear Information System (INIS)

Jianying Li; Jaszczak, R.J.; Greer, K.L.; Coleman, R.E.; Zongjian Cao; Tsui, B.M.W.

1993-01-01

A filtered backprojection (FBP) algorithm is derived to perform cone beam (CB) single-photon emission computed tomography (SPECT) reconstruction with camera tilt using circular orbits. This algorithm reconstructs the tilted angle CB projection data directly by incorporating the tilt angle into it. When the tilt angle becomes zero, this algorithm reduces to that of Feldkamp. Experimentally acquired phantom studies using both a two-point source and the three-dimensional Hoffman brain phantom have been performed. The transaxial tilted cone beam brain images and profiles obtained using the new algorithm are compared with those without camera tilt. For those slices which have approximately the same distance from the detector in both tilt and non-tilt set-ups, the two transaxial reconstructions have similar profiles. The two-point source images reconstructed from this new algorithm and the tilted cone beam brain images are also compared with those reconstructed from the existing tilted cone beam algorithm. (author)

Ray tracing reconstruction investigation for C-arm tomosynthesis

Science.gov (United States)

Malalla, Nuhad A. Y.; Chen, Ying

2016-04-01

C-arm tomosynthesis is a three dimensional imaging technique. Both x-ray source and the detector are mounted on a C-arm wheeled structure to provide wide variety of movement around the object. In this paper, C-arm tomosynthesis was introduced to provide three dimensional information over a limited view angle (less than 180o) to reduce radiation exposure and examination time. Reconstruction algorithms based on ray tracing method such as ray tracing back projection (BP), simultaneous algebraic reconstruction technique (SART) and maximum likelihood expectation maximization (MLEM) were developed for C-arm tomosynthesis. C-arm tomosynthesis projection images of simulated spherical object were simulated with a virtual geometric configuration with a total view angle of 40 degrees. This study demonstrated the sharpness of in-plane reconstructed structure and effectiveness of removing out-of-plane blur for each reconstruction algorithms. Results showed the ability of ray tracing based reconstruction algorithms to provide three dimensional information with limited angle C-arm tomosynthesis.

Muon reconstruction and the search for leptoquarks at LHC

CERN Document Server

Ruckert, B

2006-01-01

This diploma thesis focuses on the reconstruction of high-energetic muons. This simulation study was performed within the ATLAS experiment at the Large Hadron Collider (LHC) which is a pp-collider with a centre-of-mass energy p s = 14 TeV. The purpose of this study was to identify muons with strongly overestimated transverse momentum using Monte Carlo simulated data which has been generated using Pythia and run through a full detector simulation. These muons can lead to a faked leptoquark signal, as leptoquark-decays can include high-energetic muons. If leptoquarks exist, only a small number of such events is expected which makes the safe momentum measurement a crucial point. To achieve an optimal reconstruction, selection criteria have been developed which compare the track’s 2, the particle’s -direction and the reconstructed pT s from the different reconstruction algorithms, namely the inner detector standalone reconstruction, the muon spectrometer standalone reconstruction and a combination of both. Th...

Vertex Reconstruction in the ATLAS Experiment at the LHC

CERN Document Server

Bouhova-Thacker, E; The ATLAS collaboration; Kostyukhin, V; Liebig, W; Limper, M; Piacquadio, G; Lichard, P; Weiser, C; Wildauer, A

2009-01-01

In the harsh environment of the Large Hadron Collider at CERN (design luminosity of $10^{34}$ cm$^{-2}$ s$^{-1}$) efficient reconstruction of vertices is crucial for many physics analyses. Described in this paper are the strategies for vertex reconstruction used in the ATLAS experiment and their implementation in the software framework Athena. The algorithms for the reconstruction of primary and secondary vertices as well as for finding of photon conversions and vertex reconstruction in jets are described. A special emphasis is made on the vertex fitting with application of additional constraints. The implementation of mentioned algorithms follows a very modular design based on object-oriented C++ and use of abstract interfaces. The user-friendly concept allows event reconstruction and physics analyses to compare and optimize their choice among different vertex reconstruction strategies. The performance of implemented algorithms has been studied on a variety of Monte Carlo samples and results are presented.

Reconstruction of FXR Beam Conditions

International Nuclear Information System (INIS)

Nexen, W E; Scarpetti, R D; Zentler, J

2001-01-01

Beam-envelope radius, envelope angle, and beam emittance can be derived from measurements of beam radius for at least three different transport conditions. We have used this technique to reconstruct exit parameters from the FXR injector and accelerator. We use a diamagnetic loop (DML) to measure the magnetic moment of the high current beam. With no assumptions about radial profile, we can derive the beam mean squire radius from the moment under certain easily met conditions. Since it is this parameter which is required for the reconstruction, it is evident that the DML is the ideal diagnostic for this technique. The simplest application of this technique requires at least three shots for a reconstruction but in reality requires averaging over many more shots because of shot to shot variation. Since DML measurements do not interfere with the beam, single shot time resolved measurements of the beam parameters appear feasible if one uses an array of at least three DMLs separated by known transport conditions

Avoiding Complications with MPFL Reconstruction.

Science.gov (United States)

Smith, Marvin K; Werner, Brian C; Diduch, David R

2018-05-12

To discuss the potentially significant complications associated with medial patellofemoral ligament (MPFL) reconstruction. Additionally, to review the most current and relevant literature with an emphasis on avoiding these potential complications. Multiple cadaveric studies have characterized the anatomy of the MPFL and the related morphologic abnormalities that contribute to recurrent lateral patellar instability. Such abnormalities include patella alta, excessive tibial tubercle to trochlear grove (TT-TG) distance, trochlear dysplasia, and malalignment. Recent studies have evaluated the clinical outcomes associated with the treatment of concomitant pathology in combination with MPFL reconstruction, which is critical in avoiding recurrent instability and complications. Although there remains a lack of consensus regarding various critical aspects of MPFL reconstruction, certain concepts remain imperative. Our preferred methods and rationales for surgical techniques are described. These include appropriate work up, a combination of procedures to address abnormal morphology, anatomical femoral insertion, safe and secure patellar fixation, appropriate graft length fixation, and thoughtful knee flexion during fixation.

Reconstructing a general inflationary action

International Nuclear Information System (INIS)

Bean, Rachel; Chung, Daniel J. H.; Geshnizjani, Ghazal

2008-01-01

If inflation is to be considered in an unbiased way, as possibly originating from one of a wide range of underlying theories, then observations need not be simply applied to reconstructing the inflaton potential V(φ) or a specific kinetic term, as in Dirac-Born-Infeld inflation, but rather to reconstruct the inflationary action in its entirety. We discuss the constraints that can be placed on a general single field action from measurements of the primordial scalar and tensor fluctuation power spectra and non-Gaussianities. The analytic form of the action that is consistent with data turns out to be surprisingly simple and easy to categorize. We also present the flow equation formalism for reconstructing a general inflationary Lagrangian L(X,φ), with X=(1/2)∂ μ φ∂ μ φ, in a general gauge, that reduces to canonical and DBI inflation in the specific gauge L X =c s -1 .

Arterial cross-section reconstruction from bi-plane X-ray shadowgraphs

International Nuclear Information System (INIS)

Fenster, P.; Barba, J.; Suardiaz, M.; Wong, K.K.; Herrold, E.M.; Kenet, R.O.; Borer, J.S.

1987-01-01

An iterative algorithm was used to reconstruct the cross-section of a crescent-shaped vessel lumen. The accuracy of this method was evaluated by comparing reconstruction error in the presence of Gaussian noise of different magnitudes. The sensitivity of the reconstruction algorithm to initial boundary constraint error was also evaluated. Using this algorithm, the reconstruction error was 1.7% when applied to crescent shaped lumen. This error was found to increase significantly with increasing Gaussian noise (error range: 5.75 - 20.75% for noise variance 1-8 pixels). Median filtering of the noise-degraded density profiles improved the reconstruction error (error range: 3.25 - 10.5% for noise variance 1-8 pixels). The mean reconstruction error was not strongly influenced by initial boundary constraint error. The algorithm provided reasonable reconstruction results when applied to X-ray image derived density profiles of known luminal shapes

Trends in breast reconstruction: Implications for the National Health Insurance Service.

Science.gov (United States)

Hong, Ki Yong; Son, Yoosung; Chang, Hak; Jin, Ung Sik

2018-05-01

Breast reconstruction has become more common as mastectomy has become more frequent. In Korea, the National Health Insurance Service (NHIS) began covering breast reconstruction in April 2015. This study aimed to investigate trends in mastectomy and breast reconstruction over the past 10 years and to evaluate the impact of NHIS coverage on breast reconstruction. Nationwide data regarding mastectomy and breast reconstruction were collected from the Korean Breast Cancer Society registry database. Multiple variables were analyzed in the records of patients who underwent breast reconstruction from January 2005 to March 2017 at a single institution. At Seoul National University Hospital, the total number of reconstruction cases increased 13-fold from 2005 to 2016. The proportion of immediate breast reconstruction (IBR) cases out of all cases of total mastectomy increased from 4% in 2005 to 52.0% in 2016. The proportion of delayed breast reconstruction (DBR) cases out of all cases of breast reconstruction and the overall number of DBR cases increased from 8.8% (20 cases) in 2012 to 18.3% (76 cases) in 2016. After NHIS coverage was initiated, the proportions of IBR and DBR showed statistically significant increases (PNHIS coverage (PNHIS coverage. It is expected that breast reconstruction will be a routine option for patients with breast cancer under the NHIS.

Sustained release nimesulide microparticles: evaluation of release modifying property of ethy

International Nuclear Information System (INIS)

Khan, S.A.; Ahmed, M.; Nisar-ur-Rehman; Madni, A.U.; Aamir, M.N.; Murtaza, G.

2011-01-01

Microencapsulated controlled-release preparations of nimesulide were formulated. Microparticles were prepared by modified phase separation (non-solvent addition) technique using different ratios of ethylcellulose. The microparticles (M/sub 1/, M/sub 2/, and M/sub 3/) were yellow, free flowing and spherical in shape with the particle size varying from 93.62 +- 14.15 to 104.19 +- 18.15 mu m. The t/sub 60%/of nimesulide release from microparticles was found to be 3 +- 0.6, 5 +- 0.6 and 8 +- 0.8 h for formulations M/sub 1/, M/sub 2/, and M/sub 3/, respectively. FT-IR, XRD, and thermal analysis were done which showed that there is no interaction between the polymer and drug. The mechanism of drug release from nimesulide microparticles was studied by using Higuchi and Korsmeyer-Peppas models. The value of coefficient of determination (R/sup 2/) for M/sub 1/, M/sub 2/, and M/sub 3/ indicates anomalous and case-II transport release mechanism. The dissolution data of designed system verified its ability to maintain plasma concentration without the need of frequent dosing. The Nimesulide microparticles prolonged drug release for 12 hours or longer. Based on the results of release studies, M/sub 3/ was opted as a suitable microparticulate formulation allowing the controlled release of nimesulide over a prolonged period of time. Moreover, its encapsulation efficiency was also comparable to the other two formulations (M/sub 1/ and M/sub 2/). In conclusion, the influence of polymer concentration should be considered during formulation development. (author)

Prevalence of Body Dysmorphic Disorder Among Patients Seeking Breast Reconstruction.

Science.gov (United States)

Metcalfe, Drew B; Duggal, Claire S; Gabriel, Allen; Nahabedian, Maurice Y; Carlson, Grant W; Losken, Albert

2014-07-01

Body dysmorphic disorder (BDD) is characterized by a preoccupation with a slight or imagined defect in physical appearance. It has significant implications for patients who desire breast reconstruction, because patient satisfaction with the aesthetic outcome is a substantial contributor to the success of the procedure. The authors estimated the prevalence of BDD among women seeking breast reconstruction by surveying patients with the previously validated Dysmorphic Concerns Questionnaire (DCQ). One hundred eighty-eight women who presented for immediate or delayed breast reconstruction completed the DCQ anonymously, during initial consultation with a plastic surgeon. Two groups of respondents were identified: those who desired immediate reconstruction and those who planned to undergo delayed reconstruction. The prevalence of BDD among breast reconstruction patients was compared between the 2 groups, and the overall prevalence was compared with published rates for the general public. Body dysmorphic disorder was significantly more prevalent in breast reconstruction patients than in the general population (17% vs 2%; P < .001). It also was much more common among patients who planned to undergo delayed (vs immediate) reconstruction (34% vs 13%; P = .004). Relative to the general public, significantly more women who sought breast reconstruction were diagnosed as having BDD. Awareness of the potential for BDD will enable clinicians to better understand their patients' perspectives and discuss realistic expectations at the initial consultation. Future studies are warranted to examine the implications of BDD on patient satisfaction with reconstructive surgery. 3. © 2014 The American Society for Aesthetic Plastic Surgery, Inc.