Diagnostic strategy for occult hepatitis B virus infection

Science.gov (United States)

Ocana, Sara; Casas, Maria Luisa; Buhigas, Ingrid; Lledo, Jose Luis

2011-01-01

In 2008, the European Association for the study of the liver (EASL) defined occult hepatitis B virus infection (OBI) as the “presence of hepatitis B virus (HBV) DNA in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen (HBsAg) negative by currently available assays”. Several aspects of occult HBV infection are still poorly understood, including the definition itself and a standardized approach for laboratory-based detection, which is the purpose of this review. The clinical significance of OBI has not yet been established; however, in terms of public health, the clinical importance arises from the risk of HBV transmission. Consequently, it is important to detect high-risk groups for occult HBV infection to prevent transmission. The main issue is, perhaps, to identify the target population for screening OBI. Viremia is very low or undetectable in occult HBV infection, even when the most sensitive methods are used, and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients. However, this diagnostic approach is obviously unsuitable: blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection < 10 IU/mL for HBV DNA and < 0.1 ng/mL for HBsAg. PMID:21472120

First results from stellar occultations in the "GAIA era"

Science.gov (United States)

Benedetti-Rossi, G.; Vieira-Martins, R.; Sicardy, B.

2017-09-01

Stellar occultation is a powerful technique to study distant solar system bodies. It allows high angular resolution of the occulting body from the analysis of a light curve acquired with high temporal resolution with uncertainties comparable as probes. In the "GAIA era", stellar occultations is now able to obtain even more impressive results such as the presence of atmosphere, rings and topographic features.

Boundary diffraction wave integrals for diffraction modeling of external occulters

OpenAIRE

Cady, E.

2012-01-01

An occulter is a large diffracting screen which may be flown in conjunction with a telescope to image extrasolar planets. The edge is shaped to minimize the diffracted light in a region beyond the occulter, and a telescope may be placed in this dark shadow to view an extrasolar system with the starlight removed. Errors in position, orientation, and shape of the occulter will diffract additional light into this region, and a challenge of modeling an occulter system is to accurately and quickly...

21 CFR 864.6550 - Occult blood test.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Occult blood test. 864.6550 Section 864.6550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6550 Occult blood test. (a...

Less-tight versus tight control of hypertension in pregnancy.

Science.gov (United States)

Magee, Laura A; von Dadelszen, Peter; Rey, Evelyne; Ross, Susan; Asztalos, Elizabeth; Murphy, Kellie E; Menzies, Jennifer; Sanchez, Johanna; Singer, Joel; Gafni, Amiram; Gruslin, Andrée; Helewa, Michael; Hutton, Eileen; Lee, Shoo K; Lee, Terry; Logan, Alexander G; Ganzevoort, Wessel; Welch, Ross; Thornton, Jim G; Moutquin, Jean-Marie

2015-01-29

The effects of less-tight versus tight control of hypertension on pregnancy complications are unclear. We performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational hypertension, office diastolic blood pressure of 90 to 105 mm Hg (or 85 to 105 mm Hg if the woman was taking antihypertensive medications), and a live fetus. Women were randomly assigned to less-tight control (target diastolic blood pressure, 100 mm Hg) or tight control (target diastolic blood pressure, 85 mm Hg). The composite primary outcome was pregnancy loss or high-level neonatal care for more than 48 hours during the first 28 postnatal days. The secondary outcome was serious maternal complications occurring up to 6 weeks post partum or until hospital discharge, whichever was later. Included in the analysis were 987 women; 74.6% had preexisting hypertension. The primary-outcome rates were similar among 493 women assigned to less-tight control and 488 women assigned to tight control (31.4% and 30.7%, respectively; adjusted odds ratio, 1.02; 95% confidence interval [CI], 0.77 to 1.35), as were the rates of serious maternal complications (3.7% and 2.0%, respectively; adjusted odds ratio, 1.74; 95% CI, 0.79 to 3.84), despite a mean diastolic blood pressure that was higher in the less-tight-control group by 4.6 mm Hg (95% CI, 3.7 to 5.4). Severe hypertension (≥160/110 mm Hg) developed in 40.6% of the women in the less-tight-control group and 27.5% of the women in the tight-control group (Phypertension. (Funded by the Canadian Institutes of Health Research; CHIPS Current Controlled Trials number, ISRCTN71416914; ClinicalTrials.gov number, NCT01192412.).

Occult spinal dysraphism

African Journals Online (AJOL)

paediatricians, paediatric neurosurgeons, urologists, orthopaedic surgeons, occupational ... Occult spinal dysraphism refers to a diverse group of congenital abnormalities resulting from varying degrees of disordered neuro- embryogenesis. Several terms have .... can image the whole spine. T1-weighted sagittal and axial ...

First light of an external occulter testbed at flight Fresnel numbers

Science.gov (United States)

Kim, Yunjong; Sirbu, Dan; Hu, Mia; Kasdin, Jeremy; Vanderbei, Robert J.; Harness, Anthony; Shaklan, Stuart

2017-01-01

Many approaches have been suggested over the last couple of decades for imaging Earth-like planets. One of the main candidates for creating high-contrast for future Earth-like planets detection is an external occulter. The external occulter is a spacecraft flown along the line-of-sight of a space telescope to suppress starlight and enable high-contrast direct imaging of exoplanets. The occulter is typically tens of meters in diameter and the separation from the telescope is of the order of tens of thousands of kilometers. Optical testing of a full-scale external occulter on the ground is impossible because of the long separations. Therefore, laboratory verification of occulter designs is necessary to validate the optical models used to design and predict occulter performance. At Princeton, we have designed and built a testbed that allows verification of scaled occulter designs whose suppressed shadow is mathematically identical to that of space occulters. The goal of this experiment is to demonstrate a pupil plane suppression of better than 1e-9 with a corresponding image plane contrast of better than 1e-11. The occulter testbed uses a 77.2 m optical propagation distance to realize the flight Fresnel number of 14.5. The scaled mask is placed at 27.2 m from the artificial source and the camera is located 50.0 m from the scaled mask. We will use an etched silicon mask, manufactured by the Microdevices Lab(MDL) of the Jet Propulsion Laboratory(JPL), as the occulter. Based on conversations with MDL, we expect that 0.5 μm feature size is an achievable resolution in the mask manufacturing process and is therefore likely the indicator of the best possible performance. The occulter is illuminated by a diverging laser beam to reduce the aberrations from the optics before the occulter. Here, we present first light result of a sample design operating at a flight Fresnel number and the experimental setup of the testbed. We compare the experimental results with simulations

Possible occultation by Pluto from US East Coast

Science.gov (United States)

Waagen, Elizabeth O.

2012-06-01

We have been asked to help disseminate the news of a possible occultation by Pluto visible to observers on the US East coast. Although the AAVSO does not ordinarily issue announcements of upcoming occultations, in this case the object is Pluto and the NASA New Horizons mission (http://www.nasa.gov/mission_pages/newhorizons/main/index.html) will be visiting Pluto in 2015. The information below has been supplied by Dr. Leslie Young (Southwest Research Institute), who is coordinating this observing campaign on Pluto. Dr. Young is also Deputy Project Scientist for the New Horizons mission. ALERT: Possible Pluto occultation Wednesday night (2012/06/14 03:28 UT) from US East coast. CONTACT: Leslie Young (layoung@boulder.swri.edu; work: 303-546-6057; skype: drpluto). Also see our planning pages in progress at http://wiki.boulder.swri.edu/mediawiki/index.php/2012-06-14_Pluto_occultation. Pluto's thin, nitrogen atmosphere is in vapor-pressure equilibrium with the surface ice, and changes seasonally. We've seen it double since 1988, and now we measure its pressure once or twice a year. The technique we use is stellar occultation, when a star passes behind Pluto's atmosphere. The atmosphere defocuses the starlight. By the timing of the fading of the star, we measure the pressure and temperature in Pluto's atmosphere at ~10 km resolution. MORE INFORMATION: See http://wiki.boulder.swri.edu/mediawiki/index.php/2012-06-14_Pluto_occultation.

Prime tight frames

DEFF Research Database (Denmark)

Lemvig, Jakob; Miller, Christopher; Okoudjou, Kasso A.

2014-01-01

to suggest effective analysis and synthesis computation strategies for such frames. Finally, we describe all prime frames constructed from the spectral tetris method, and, as a byproduct, we obtain a characterization of when the spectral tetris construction works for redundancies below two.......We introduce a class of finite tight frames called prime tight frames and prove some of their elementary properties. In particular, we show that any finite tight frame can be written as a union of prime tight frames. We then characterize all prime harmonic tight frames and use thischaracterization...

Occult carbon monoxide poisoning.

Science.gov (United States)

Kirkpatrick, J N

1987-01-01

A syndrome of headache, fatigue, dizziness, paresthesias, chest pain, palpitations and visual disturbances was associated with chronic occult carbon monoxide exposure in 26 patients in a primary care setting. A causal association was supported by finding a source of carbon monoxide in a patient's home, workplace or vehicle; results of screening tests that ruled out other illnesses; an abnormally high carboxyhemoglobin level in 11 of 14 patients tested, and abatement or resolution of symptoms when the source of carbon monoxide was removed. Exposed household pets provided an important clue to the diagnosis in some cases. Recurrent occult carbon monoxide poisoning may be a frequently overlooked cause of persistent or recurrent headache, fatigue, dizziness, paresthesias, abdominal pain, diarrhea and unusual spells.

Radio Occultation Bending Angle Anomalies During Tropical Cyclones

DEFF Research Database (Denmark)

Biondi, Riccardo; Neubert, Torsten; Syndergaard, Stig

signature in radio occultation profiles in the tropical tropopause layer. Using tropical cyclone best track database and data from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC), we show that the bending angle anomaly of a GPS radio occultation signal is typically larger...

Occult spondyloarthritis in inflammatory bowel disease.

Science.gov (United States)

Bandinelli, Francesca; Manetti, Mirko; Ibba-Manneschi, Lidia

2016-02-01

Spondyloarthritis (SpA) is a frequent extra-intestinal manifestation in patients with inflammatory bowel disease (IBD), although its real diffusion is commonly considered underestimated. Abnormalities in the microbioma and genetic predisposition have been implicated in the link between bowel and joint inflammation. Otherwise, up to date, pathogenetic mechanisms are still largely unknown and the exact influence of the bowel activity on rheumatic manifestations is not clearly explained. Due to evidence-based results of clinical studies, the interest on clinically asymptomatic SpA in IBD patients increased in the last few years. Actually, occult enthesitis and sacroiliitis are discovered in high percentages of IBD patients by different imaging techniques, mainly enthesis ultrasound (US) and sacroiliac joint X-ray examinations. Several diagnostic approaches and biomarkers have been proposed in an attempt to correctly classify and diagnose clinically occult joint manifestations and to define clusters of risk for patient screening, although definitive results are still lacking. The correct recognition of occult SpA in IBD requires an integrated multidisciplinary approach in order to identify common diagnostic and therapeutic strategies. The use of inexpensive and rapid imaging techniques, such as US and X-ray, should be routinely included in daily clinical practice and trials to correctly evaluate occult SpA, thus preventing future disability and worsening of quality of life in IBD patients.

Occult Macular Dystrophy

Directory of Open Access Journals (Sweden)

Işıl Sayman Muslubaş

2016-04-01

Full Text Available Occult macular dystrophy is an inherited macular dystrophy characterized by a progressive decline of bilateral visual acuity with normal fundus appearance, fluorescein angiogram and full-field electroretinogram. This case report presents a 20-year-old female patient with bilateral progressive decline of visual acuity for six years. Her visual acuity was 3-4/10 in both eyes. Anterior segment and fundus examination, fluorescein angiogram and full-field electroretinogram were normal. She could read all Ishihara pseudoisochromatic plates. Fundus autofluorescence imaging was normal. There was a mild central hyporeflectance on fundus infrared reflectance imaging in both eyes. Reduced foveal thickness and alterations of the photoreceptor inner and outer segment junction were observed by optical coherence tomography in both eyes. Central scotoma was also found by microperimetry and reduced central response was revealed by multifocal electroretinogram in both eyes. These findings are consistent with the clinical characteristics of occult macular dystrophy

Uso da ultra-sonografia na triagem de disrafismos espinhais ocultos Screening of occult spinal dysraphism by ultrasonography

Directory of Open Access Journals (Sweden)

José Gilberto de Brito Henriques

2004-09-01

Full Text Available O uso da ultra-sonografia para diagnóstico de lesões da coluna vertebral é difundido desde a década de oitenta. Suas aplicações envolvem: diagnóstico de lesões medulares traumáticas; uso intra-operatório em cirurgias do trauma e tumores medulares; uso pré-operatório e evolutivo em pacientes com disrafismos espinhais; diagnóstico pré-natal dos disrafismos; diagnóstico dos disrafismos espinhais ocultos ao nascimento. Pacientes com suspeita de disrafismo espinhal oculto (estigmas cutâneos em linha média ou história familiar de disrafismos representaram a principal indicação do exame que foi realizado em 292 pacientes do Hospital das Clínicas da Universidade Federal de Minas Gerais. Alterações como lipomas do cone medular, medula baixa, filo terminal espesso, cistos da ponta do cone medular e seios dérmicos foram identificados com fidelidade à ultra-sonografia. A interpretação do exame não apresentou dificuldades técnicas. Sua realização é rápida, não é necessária sedação, apresenta baixo custo e idealmente deve ser realizado pelo próprio neurocirurgião devido ao grande número de informações possíveis durante o exame. O exame entretanto não substitui a ressonância magnética mas pode ser um bom método de triagem para os pacientes.Ultrasonography for diagnosis of spinal cord diseases has been used since the eighties. There are different fields for its use: traumatic spine lesions, intra-operative use in trauma and spine tumors surgery, pre-operative and follow up study for spinal dysraphism, occult spinal dysraphism of the newborn. Patients with suspected occult spinal dysraphism are the most important indication for the method. Utrasonography was performed in 292 patients of Hospital das Clínicas, Universidade Federal de Minas Gerais. Lesions such as conus medullaris lipomas, low level of conus medullaris, filum terminale tethering, cauda equina cysts and dermal sinuses can be well demonstrated. There

The stellar occultation by the dwarf planet Haumea

Science.gov (United States)

Santos-Sanz, Pablo; Ortiz, Jose Luis; Sicardy, Bruno; Rossi, Gustavo; Berard, Diane; Morales, Nicolas; Duffard, Rene; Braga-Ribas, Felipe; Hopp, Ulrich; Ries, Christoph; Nascimbeni, Valerio; Marzari, Francesco; Granata, Valentina; Pál, András; Kiss, Csaba; Pribulla, Theodor; Milan Komzík, Richard; Hornoch, Kamil; Pravec, Petr; Bacci, Paolo; Maestripieri, Martina; Nerli, Luca; Mazzei, Leonardo; Bachini, Mauro; Martinelli, Fabio; Succi, Giacomo; Ciabattari, Fabrizio; Mikuz, Herman; Carbognani, Albino; Gaehrken, Bernd; Mottola, Stefano; Hellmich, Stephan; Rommel, Flavia; Fernández-Valenzuela, Estela; Campo Bagatin, Adriano; Haumea occultation international Collaboration: https://cloud.iaa.csic.es/public.php?service=files&t=d9276f8ab1a316cef13bee28bef75add

2017-10-01

The dwarf planet Haumea is a very peculiar Trans-Neptunian Object (TNO) with unique and exotic characteristics. It is currently classified as one of the five dwarf planets of the solar system, and it is the only one for which size, shape, albedo, density and other basic properties were not accurately known. To solve that we predicted an occultation of the star GaiaDR1 1233009038221203584 by Haumea and organized observations within the expected shadow path. Medium/large telescopes were needed to record the occultation with enough signal to noise ratio because the occulted star is of similar brightness as Haumea (R~17.7 mag). We will report results derived from this successful stellar occultation by Haumea on 2017 January 21st. The occultation was positive from 12 telescopes at 10 observing stations in Europe: the Asiago Observatory 1.8m telescope (Italy), the Mount Agliale Observatory 0.5m telescope (Italy), the Lajatico Astronomical Centre 0.5m telescope (Italy), the S.Marcello Pistoiese Observatory 0.6m telescope (Italy), the Crni Vrh Observatory 0.6m telescope (Slovenia), the Ondrejov Observatory 0.65m telescope (Czech Republic), the Bavarian Public Observatory 0.81m telescope (Germany), the Konkoly Observatory 1m and 0.6m telescopes (Hungary), the Skalnate Pleso Observatory 1.3m telescope (Slovakia), and the Wendelstein Observatory 2m and 0.4m telescopes (Germany). This is the occultation by a TNO with the largest number of chords ever recorded.Part of this work has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 687378.

Occult diaphragmatic injuries caused by stab wounds.

Science.gov (United States)

Leppäniemi, Ari; Haapiainen, Reijo

2003-10-01

Missed diaphragmatic perforation caused by penetrating trauma can lead to subsequent strangulation of a hollow viscus, which has prompted the use of invasive diagnostic procedures to exclude occult diaphragmatic injuries in asymptomatic, high-risk patients. The objective of this study was to determine the incidence of occult diaphragmatic injuries caused by stab wounds of the lower chest and upper abdomen, and to examine the natural history and consequences of missed diaphragmatic injuries. On the basis of patient data from two previous randomized studies from our institution, a retrospective analysis was performed on 97 patients treated for anterior stab wounds located between the nipple line, the umbilical level, and the posterior axillary lines not having indications for immediate surgical exploration. The patients were divided into two groups on the basis of their initial randomized management (open or laparoscopic exploration vs. expectant observation). In the exploration group (n = 47), four diaphragmatic injuries (9%) were detected (three left-sided and one right-sided). Excluding patients with associated injuries requiring surgical repair, the incidence of occult diaphragmatic injuries was 3 of 43 (7%). In the observation group (n = 50), there were two patients (4%) with delayed presentation of missed left-sided diaphragmatic injury 2 and 23 months later, respectively. Both injuries resulted from stab wounds of the left flank and presented with herniation of the stomach or small bowel and colon. The overall incidence of occult diaphragmatic injuries in left-sided thoracoabdominal stab wounds was 4 of 24 (17%), and was much lower after stab wounds of left epigastrium (0%), right lower chest (0%), and right epigastrium (4%). In asymptomatic patients with anterior or flank stab wounds of the lower chest or upper abdominal area, the risk of an occult diaphragmatic injury is approximately 7% which, if undetected, is associated with a high risk of subsequent

Characterization and evolution of distant planetary atmospheres using stellar occultations

Science.gov (United States)

Young, L. A.

2008-09-01

Ground-based or near-Earth (e.g., HST) stellar occultations of every atmosphere in our solar system has been observed: Venus, Mars, Jupiter, Saturn, Titan, Uranus, Neptune, Triton, and Pluto [1]. These observations probe the atmospheres at roughly 0.1 to 100 microbar. I will talk about three aspects of stellar occultations: one-dimensional vertical profiles of the atmosphere, two- or three-dimensional atmospheric states, and the time evolution of atmosphere. In all three, I will draw on recent observations, with an emphasis on Pluto. Occultations are particularly important for the study of Pluto's atmosphere, which is impossible to study with imaging, and extremely difficult to study with spectroscopy. It was discovered by stellar occultation in 1988 [2]. No subsequent Pluto occultations were observed until two events in 2002 [3]. Pluto is now crossing the galactic plane, and there have been several additional occultations observed since 2006. These include a high signal-to-noise observation from the Anglo Australian Observatory in 2006 [4] (Fig 1), densely spaced visible and infrared observations of Pluto's upper atmosphere from telescopes in the US and Mexico in March, 2007 [5] (Fig. 2), and a dualwavelength central flash observation from Mt. John in July, 2007 [6] (Fig 3). The flux from a star occulted by an atmosphere diminishes primarily due to the increase in refraction with depth in the atmosphere, defocusing the starlight, although absorption and tangential focusing can also contribute. Because the atmospheric density, to first order, follows an exponential, it is feasible to derive a characteristic pressure and temperature from isothermal fits to even low-quality occultation light curves. Higher quality light curves allow fits with more flexible models, or light curve inversions that derive temperatures limited by the resolution of the data. These allow the derivation of one-dimensional profiles of temperature and pressure vs. altitude, which are critical

Fecal Occult Blood Test and Gastrointestinal Parasitic Infection

Directory of Open Access Journals (Sweden)

Majed H. Wakid

2010-01-01

Full Text Available Stool specimens of 1238 workers in western region of Saudi Arabia were examined for infection with intestinal parasites and for fecal occult blood (FOB to investigate the possibility that enteroparasites correlate to occult intestinal bleeding. Direct smears and formal ether techniques were used for detection of diagnostic stages of intestinal parasites. A commercially available guaiac test was used to detect fecal occult blood. 47.01% of the workers were infected with intestinal parasites including eight helminthes species and eight protozoan species. The results provided no significant evidence (P-value=0.143 that intestinal parasitic infection is in association with positive guaiac FOB test.

CT detection of occult pneumothorax in head trauma

International Nuclear Information System (INIS)

Tocino, I.M.; Miller, M.H.; Frederick, P.R.; Bahr, A.L.; Thomas, F.

1984-01-01

A prospective evaluation for occult pneumothorax was performed in 25 consecutive patients with serious head trauma by combining a limited chest CT examination with the emergency head CT examination. Of 21 pneuomothoraces present in 15 patients, 11 (52%) were found only by chest CT and were not identified clinically or by supine chest radiograph. Because of pending therapeutic measures, chest tubes were placed in nine of the 11 occult pneumothoraces, regardless of the volume. Chest CT proved itself as the most sensitive method for detection of occult pneumothorax, permitting early chest tube placement to prevent transition to a tension pneumothorax during subsequent mechanical ventilation or emergency surgery under general anesthesia

CT detection of occult pneumothorax in head trauma

Energy Technology Data Exchange (ETDEWEB)

Tocino, I.M.; Miller, M.H.; Frederick, P.R.; Bahr, A.L.; Thomas, F.

1984-11-01

A prospective evaluation for occult pneumothorax was performed in 25 consecutive patients with serious head trauma by combining a limited chest CT examination with the emergency head CT examination. Of 21 pneuomothoraces present in 15 patients, 11 (52%) were found only by chest CT and were not identified clinically or by supine chest radiograph. Because of pending therapeutic measures, chest tubes were placed in nine of the 11 occult pneumothoraces, regardless of the volume. Chest CT proved itself as the most sensitive method for detection of occult pneumothorax, permitting early chest tube placement to prevent transition to a tension pneumothorax during subsequent mechanical ventilation or emergency surgery under general anesthesia.

Wave propagation simulation of radio occultations based on ECMWF refractivity profiles

DEFF Research Database (Denmark)

von Benzon, Hans-Henrik; Høeg, Per

2015-01-01

This paper describes a complete radio occultation simulation environment, including realistic refractivity profiles, wave propagation modeling, instrument modeling, and bending angle retrieval. The wave propagator is used to simulate radio occultation measurements. The radio waves are propagated...... of radio occultations. The output from the wave propagator simulator is used as input to a Full Spectrum Inversion retrieval module which calculates geophysical parameters. These parameters can be compared to the ECMWF atmospheric profiles. The comparison can be used to reveal system errors and get...... a better understanding of the physics. The wave propagation simulations will in this paper also be compared to real measurements. These radio occultations have been exposed to the same atmospheric conditions as the radio occultations simulated by the wave propagator. This comparison reveals that precise...

Pluto-Charon Stellar Occultation Candidates: 1990-1995

Science.gov (United States)

Dunham, E. W.; McDonald, S. W.; Elliot, J. L.

1991-01-01

We have carried out a search to identify stars that might be occulted by Pluto or Charon during the period 1990-1995 and part of 1996. This search was made with an unfiltered CCD camera operated in the strip scanning mode, and it reaches an R magnitude of approximately 17.5-about 1.5 mag fainter than previous searches. Circumstances for each of the 162 potential occultations are given, including an approximate R magnitude of the star, which allows estimation of the signal-to-noise ratio (S/N) for observation of each occultation. The faintest stars in our list would yield an S/N of about 20 for a 1 S integration when observed with a CCD detector on an 8 m telescope under a dark sky. Our astrometric precision (+/- 0.2 arcsec, with larger systematic errors possible for individual cases) is insufficient to serve as a final prediction for these potential occultations, but is sufficient to identify stars deserving of further, more accurate, astrometric observations. Statistically, we expect about 32 of these events to be observable somewhere on Earth. The number of events actually observed will be substantially smaller because of clouds and the sparse distribution of large telescopes. Finder charts for each of the 91 stars involved are presented.

Predictions of stellar occultations by TNOs/Centaurs using Gaia

Science.gov (United States)

Desmars, Josselin; Camargo, Julio; Berard, Diane; Sicardy, Bruno; Leiva, Rodrigo; Vieira-Martins, Roberto; Braga-Ribas, Felipe; Assafin, Marcelo; Rossi, Gustavo; Chariklo occultations Team, Rio Group, Lucky Star Occultation Team, Granada Occultation Team

2017-10-01

Stellar occultations are the unique technique from the ground to access physical parameters of the distant solar system objects, such as the measure of the size and the shape at kilometric level, the detection of tenuous atmospheres (few nanobars), and the investigation of close vicinity (satellites, rings, jets).Predictions of stellar occultations require accurate positions of the star and the object.The Gaia DR1 catalog now allows to get stellar position to the milliarcsecond (mas) level. The main uncertainty in the prediction remains in the position of the object (tens to hundreds of mas).Now, we take advantage of the NIMA method for the orbit determination that uses the most recent observations reduced by the Gaia DR1 catalog and the astrometric positions derived from previous positive occultations.Up to now, we have detected nearly 50 positive occultations for about 20 objects that provide astrometric positions of the object at the time of the occultation. The uncertainty of these positions only depends on the uncertainty on the position of the occulted stars, which is a few mas with the Gaia DR1 catalog. The main limitation is now on the proper motion of the star which is only given for bright stars in the Tycho-Gaia Astrometric Solution. This limitation will be solved with the publicationof the Gaia DR2 expected on April 2018 giving proper motions and parallaxes for the Gaia stars. Until this date, we use hybrid stellar catalogs (UCAC5, HSOY) that provide proper motions derived from Gaia DR1 and another stellar catalog.Recently, the Gaia team presented a release of three preliminary Gaia DR2 stellar positions involved in the occultations by Chariklo (22 June and 23 July 2017) and by Triton (5 October 2017).Taking the case of Chariklo as an illustration, we will present a comparison between the proper motions of DR2 and the other catalogs and we will show how the Gaia DR2 will lead to a mas level precision in the orbit and in the prediction of stellar

OCCULTISM AND MEDIUMSHIP IN FERNANDO PESSOA

Directory of Open Access Journals (Sweden)

Alisson Diêgo Dias de Medeiros

2016-03-01

Full Text Available This work is the result of a research on the influence that the occultism had on the work of the Portuguese poet Fernando Pessoa. To delimitate the study, we selected papers of Fernando Pessoa, which  suggested that the poet considered himself medium, and hence influenced his work, building his depersonalization. This work presents, thus, as main objectiveto analyze personal papers of Fernando Pessoa, whose outstanding characteristic is the presence of occultism and the supposed mediumship defended by him in response to non-literary and heteronymic manifestations. To this end, I focused on specific objectives, which are: a to study the speech of Fernando Pessoa on his supposed mediumship / occultism b to analyze specific texts that are, for the poet, mediumistic manifestations c to study excerpts from a set of personal letters in which Fernando Pessoa suggested being a medium. It is true that this dissertation will address many discussions already made by scholars and specialists in Fernando Pessoa, but we consider the possibility to deepen issues and contribute to the critical fortune of the poet.

Exploring small bodies in the outer solar system with stellar occultations

Science.gov (United States)

Elliot, Jim L.; Dunham, Edward W.; Olkin, C. B.

1995-01-01

Stellar occultation observations probe the atmospheric structure and extinction of outer solar system bodies with a spatial resolution of a few kilometers, and an airborne platform allows the observation of occultations by small bodies that are not visible from fixed telescopes. Results from occultations by Triton, Pluto, and Chiron observed with KAO are discussed, and future directions for this program are presented.

Diffraction-based analysis of tunnel size for a scaled external occulter testbed

Science.gov (United States)

Sirbu, Dan; Kasdin, N. Jeremy; Vanderbei, Robert J.

2016-07-01

For performance verification of an external occulter mask (also called a starshade), scaled testbeds have been developed to measure the suppression of the occulter shadow in the pupil plane and contrast in the image plane. For occulter experiments the scaling is typically performed by maintaining an equivalent Fresnel number. The original Princeton occulter testbed was oversized with respect to both input beam and shadow propagation to limit any diffraction effects due to finite testbed enclosure edges; however, to operate at realistic space-mission equivalent Fresnel numbers an extended testbed is currently under construction. With the longer propagation distances involved, diffraction effects due to the edge of the tunnel must now be considered in the experiment design. Here, we present a diffraction-based model of two separate tunnel effects. First, we consider the effect of tunnel-edge induced diffraction ringing upstream from the occulter mask. Second, we consider the diffraction effect due to clipping of the output shadow by the tunnel downstream from the occulter mask. These calculations are performed for a representative point design relevant to the new Princeton occulter experiment, but we also present an analytical relation that can be used for other propagation distances.

Less-Tight versus Tight Control of Hypertension in Pregnancy

NARCIS (Netherlands)

Magee, Laura A.; von Dadelszen, Peter; Rey, Evelyne; Ross, Susan; Asztalos, Elizabeth; Murphy, Kellie E.; Menzies, Jennifer; Sanchez, Johanna; Singer, Joel; Gafni, Amiram; Gruslin, Andrée; Helewa, Michael; Hutton, Eileen; Lee, Shoo K.; Lee, Terry; Logan, Alexander G.; Ganzevoort, Wessel; Welch, Ross; Thornton, Jim G.; Moutquin, Jean-Marie

2015-01-01

BACKGROUND The effects of less-tight versus tight control of hypertension on pregnancy complications are unclear. METHODS We performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational

Occult hepatitis B infection: an evolutionary scenario

Directory of Open Access Journals (Sweden)

Lukashov Vladimir V

2008-12-01

Full Text Available Abstract Background Occult or latent hepatitis B virus (HBV infection is defined as infection with detectable HBV DNA and undetectable surface antigen (HBsAg in patients' blood. The cause of an overt HBV infection becoming an occult one is unknown. To gain insight into the mechanism of the development of occult infection, we compared the full-length HBV genome from a blood donor carrying an occult infection (d4 with global genotype D genomes. Results The phylogenetic analysis of polymerase, core and X protein sequences did not distinguish d4 from other genotype D strains. Yet, d4 surface protein formed the evolutionary outgroup relative to all other genotype D strains. Its evolutionary branch was the only one where accumulation of substitutions suggests positive selection (dN/dS = 1.3787. Many of these substitutiions accumulated specifically in regions encoding the core/surface protein interface, as revealed in a 3D-modeled protein complex. We identified a novel RNA splicing event (deleting nucleotides 2986-202 that abolishes surface protein gene expression without affecting polymerase, core and X-protein related functions. Genotype D strains differ in their ability to perform this 2986-202 splicing. Strains prone to 2986-202 splicing constitute a separate clade in a phylogenetic tree of genotype D HBVs. A single substitution (G173T that is associated with clade membership alters the local RNA secondary structure and is proposed to affect splicing efficiency at the 202 acceptor site. Conclusion We propose an evolutionary scenario for occult HBV infection, in which 2986-202 splicing generates intracellular virus particles devoid of surface protein, which subsequently accumulates mutations due to relaxation of coding constraints. Such viruses are deficient of autonomous propagation and cannot leave the host cell until it is lysed.

Beamsteerable GNSS Radio Occultation ASIC

Data.gov (United States)

National Aeronautics and Space Administration — We will develop an integrated RF ASIC to enable high quality radio occultation (RO) weather observations using the Global Navigations System Satellite (GNSS)...

Partially Transparent Petaled Mask/Occulter for Visible-Range Spectrum

Science.gov (United States)

Shiri, Ron Shahram; Wasylkiwskyj, Wasyl

2013-01-01

The presence of the Poisson Spot, also known as the spot of Arago, has been known since the 18th century. This spot is the consequence of constructive interference of light diffracted by the edge of the obstacle where the central position can be determined by symmetry of the object. More recently, many NASA missions require the suppression of this spot in the visible range. For instance, the exoplanetary missions involving space telescopes require telescopes to image the planetary bodies orbiting central stars. For this purpose, the starlight needs to be suppressed by several orders of magnitude in order to image the reflected light from the orbiting planet. For the Earth-like planets, this suppression needs to be at least ten orders of magnitude. One of the common methods of suppression involves sharp binary petaled occulters envisioned to be placed many thousands of miles away from the telescope blocking the starlight. The suppression of the Poisson Spot by binary sharp petal tips can be problematic when the thickness of the tips becomes smaller than the wavelength of the incident beam. First they are difficult to manufacture and also it invalidates the laws of physical optics. The proposed partially transparent petaled masks/occulters compensate for this sharpness with transparency along the surface of the petals. Depending on the geometry of the problem, this transparency can be customized such that only a small region of the petal is transparent and the remaining of the surface is opaque. This feature allows easy fabrication of this type of occultation device either as a mask or occulter. A partially transparent petaled mask/ occulter has been designed for the visible spectrum range. The mask/occulter can suppress the intensity along the optical axis up to ten orders of magnitude. The design process can tailor the mask shape, number of petals, and transparency level to the near-field and farfield diffraction region. The mask/occulter can be used in space

Occult hepatitis B virus infection in immunocompromised patients

Directory of Open Access Journals (Sweden)

Ruth Nogueira Cordeiro Moraes Jardim

Full Text Available Occult hepatitis B infection is characterized by hepatitis B virus (HBV DNA in the serum in the absence of hepatitis B surface antigen (HBsAg. We assessed occult HBV infection prevalence in two groups of immunocompromised patients (maintenance hemodialysis patients and HIV-positive patients presenting HBsAg-negative and anti-HBc positive serological patterns, co-infected or not by HCV. Thirty-four hemodialysis anti-HIV negative patients, 159 HIV-positive patients and 150 blood donors who were anti-HBc positive (control group were selected. HBV-DNA was detected by nested-PCR. Occult hepatitis B infection was not observed in the hemodialysis patients group but was found in 5% of the HIV-patients and in 4% of the blood donors. Immunosuppression in HIV positive patients was not a determining factor for occult HBV infection. In addition, no significant relationship between HBV-DNA and HCV co-infection in the HIV-positive patient group was found. A lack of significant associations was also observed between positivity for HBV-DNA and CD4 count, viral load and previous lamivudine treatment in these HIV-positive patients.

Occult Hepatitis B Virus in Gezira State Sudan | Gasmelseed ...

African Journals Online (AJOL)

Background: Occult hepatitis B infection (OBI) is simply defined as serologically undetectable hepatitis B surface antigen (HBsAg-ve), despite the presence of circulating HBV DNA. Objective: The aim of this study was to determine the prevalence of occult HBV among Screened HBsAg subjects in Gezira State, Sudan.

Retrieval of Electron Density Profile for KOMPSAT-5 GPS Radio Occultation

Directory of Open Access Journals (Sweden)

Woo-Kyoung Lee

2007-12-01

Full Text Available The AOPOD (Atmosphere Occultation and Precision Orbit Determination system, the secondary payload of KOMPSAT (KOrea Multi-Purpose SATellite-5 scheduled to be launched in 2010, shall provide GPS radio occultation data. In this paper, we simulated the GPS radio occultation characteristic of KOMPSAT-5 and retrieved electron density profiles using KROPS (KASI Radio Occultation Processing Software. The electron density retrieved from CHAMP (CHAllenging Minisatellite Payload GPS radio occultation data on June 20, 2004 was compared with IRI (International Reference Ionosphere - 2001, PLP (Planar Langmuir Probe, and ionosonde measurements. When the result was compared with ionosonde measurements, the discrepancies were 5 km on the F_2 peak height (hmF_2 and 3×10^{10} el/m^3 on the electron density of the F_2 peak height (NmF_2. By comparing with the Langmuir Probe measurements of CHAMP satellite (PLP, both agrees with 1.6×10^{11} el/m^3 at the height of 365.6 km.

Recent progress on external occulter technology for imaging exosolar planets

Science.gov (United States)

Kasdin, N. J.; Vanderbei, R. J.; Sirbu, D.; Samuels, J.; Shaklan, S.; Lisman, D.; Thomson, M.; Cady, E.; Martin, S.

Imaging planets orbiting nearby stars requires a system for suppressing the host starlight by at least ten orders of magnitude. One such approach uses an external occulter, a satellite flying far from the telescope and employing a large screen, or starshade, to suppress the incoming starlight. This trades the added complexity of building the precisely shaped starshade and flying it in formation against simplifications in the telescope since extremely precise wavefront control is no longer necessary. Much progress has been made recently in designing, testing and manufacturing starshade technology. In this paper we describe the design of starshades and report on recent accomplishments in manufacturing and measuring a prototype occulter petal as part of NASA's first Technology Development for Exoplanet Missions (TDEM) program. We demonstrate that the as-built petal is consistent with a full-size occulter achieving better than 10-10 contrast. We also discuss laboratory testing at the Princeton Occulter Testbed. These experiments use sub-scale, long-distance beam propagation to verify the diffraction analysis associated with occulter starlight suppression. We demonstrate roughly 10-10 suppression in the laboratory and discuss the important challenges and limitations.

Crosslink Radio Occultation for the Remote Sensing of Planetary Atmospheres

Science.gov (United States)

Mannucci, A. J.; Ao, C. O.; Asmar, S.; Edwards, C. D.; Kahan, D. S.; Paik, M.; Pi, X.; Williamson, W.

2015-12-01

Radio occultation utilizing deep space telecommunication signals has been used with great success in the profiling of planetary atmospheres and ionospheres since the 1960s. A shortcoming of this technique, however, is the limited temporal and spatial sampling that it provides. We consider a different approach where radio occultation measurements are taken between two spacecraft orbiting an extra-terrestrial body. Such "crosslink" radio occultations between the Global Positioning System satellites and low-earth orbiting spacecraft have been routinely acquired to provide global observations of the Earth's atmosphere and ionosphere that are used for weather forecast, climate analysis, and space weather applications. The feasibility of applying this concept to other planets has recently been demonstrated for the first time, where crosslink occultation measurements have been acquired between the Mars Odyssey and Mars Reconnaissance Orbiter spacecraft. These measurements leverage the proximity link telecommunication payloads on each orbiter, which are nominally used to provide relay communication and navigation services to Mars landers and rovers. In this presentation, we will describe the Mars crosslink experiments and the corresponding data analysis in detail. In addition, we will discuss how the crosslink occultation concepts can be effectively applied in future space exploration missions.

Molecular and serological detection of occult hepatitis B virus ...

African Journals Online (AJOL)

Background: Occult hepatitis B infections are becoming a major global threat, but the available data on its prevalence in various parts of the world are often divergent. Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface antigen-negative serum using anti-HBc as a marker of previous infection.

Occult hepatitis B among Iranian hepatitis C patients

Directory of Open Access Journals (Sweden)

Ahmad shavakhi

2009-02-01

Full Text Available

• BACKGROUND: Occult hepatitis B is defined as presence of HBV DNA in tissue or serum without hepatitis B surface antigen. The aim of this study is to determine frequency of occult hepatitis B among hepatitis C patients in Tehran and compare the route of transmission and liver enzymes between positive and negative HBV DNA patients.
• METHODS: In a cross sectional study, serum of 103 hepatitis C cases (79.6% men and 20.4% women were analyzed for s, x and core genes via a nested polymerase chain reaction technique.
• RESULTS: HBV DNA was detectable in serum of 20 patients (19.4%. No significant difference in age, sex and route of transmission were seen in HBV DNA positive and negative patients. In HBV DNA positive and negative groups, mean of AST was 73, 47 (p < 0.05 and mean of ALT was 76 and 36 respectively (p < 0.05.
• CONCLUSION: Occult hepatitis B was observed in a considerable number of hepatitis C patients in Tehran. It was associated with elevation in liver enzyme but was not related to route of transmission.
• KEY WORD: Occult hepatitis B, hepatitis C, cirrhosis.

[Occultism, parapsychology and the esoteric from the perspective of psychopathology].

Science.gov (United States)

Scharfetter, C

1998-10-01

The concepts and main themes of occultism, parapsychology and esoterics are set in comparison to religion, spirituality, mysticism. The cultural relativity of these concepts is emphasised. Occultism means dealing with phenomena, processes, and/or powers which are not accessible to "normal perception". The manipulation of such powers is effected via (white, black, grey) magic. Parapsychology, in its popular sense, deals with occult phenomena, whereas scientific parapsychology investigates them empirically. Esoterics is a complex of beliefs within a hermetic tradition about occult processes and about desting after death. Transpersonal psychology deals with these issues while calling them "spiritual". Effects of paranormal experiences and actions on the side of the actor as well as the adept are discussed: personality types, interpersonal effects, crises and psychoses (mediumistic psychoses). The concept of dissociation of subpersonalities (subselves) appears to be a viable perspective to explain these phenomena. In mediumistic psychoses, the splitting of non-ego parts of the psyche leads to a manifestation of schizophrenic symptoms. Dangers for mental health are an ego inflation by self-attribution of "superhuman" power. A personality disposition for parapsychological perception and/or action may be seen in schizotypia and similar near-psychotic "personalities up the border". Adepts of occultism may present with a "false self" in the sense of Winnicott.

McDonald's and the Occult.

Science.gov (United States)

Singer, Barry

1979-01-01

Discusses "occult" and "paranormal" literature which is often mistaken for nonfiction. Suggests that most publishers are unwilling to publish scientific perspectives on the paranormal because such writings would be unmarketable. Journal availability: see SO 507 190. (KC)

Observations of Hot-Jupiter occultations combining Spitzer and Kepler photometry

Directory of Open Access Journals (Sweden)

Knutson H.

2011-02-01

Full Text Available We present the status of an ongoing program which aim at measuring occultations by their parent stars of transiting hot giant exoplanets discovered recently by Kepler. The observations are obtained in the near infrared with WarmSpitzer Space Telescope and at optical wavelengths by combining more than a year of Kepler photometry. The investigation consists of measuring the mid-occultation times and the relative occultation depths in each band-passes. Our measurements of occultations depths in the Kepler bandpass is turned into the determination of the optical geometric albedo Ag in this wavelength domain. The brightness temperatures of these planets are deduced from the infrared observations. We combine the optical and near infrared planetary emergent fluxes to obtain broad band emergent spectra of individual planet. We finally compare these spectra to hot Jupiter atmospheric models in order broadly distinguishing these atmospheres between different classes of models.

Prevalence of occult inflammatory bowel disease in ankylosing spondylitis.

Science.gov (United States)

Costello, P B; Alea, J A; Kennedy, A C; McCluskey, R T; Green, F A

1980-10-01

Fifty-five patients with ankylosing spondylitis and 16 control patients matched for sex and age were examined for evidence of occult inflammatory bowel disease. In all patients evaluation included history and physical examination, barium enema, sigmoidoscopy, and rectal biopsy. The results of this study suggest that there is no increased prevalence of occult inflammatory bowel disease in patients with ankylosing spondylitis.

Operation of the Radio Occultation Mission in KOMPSAT-5

Directory of Open Access Journals (Sweden)

Mansoo Choi

2010-12-01

Full Text Available Korea multi-purpose satellite-5 (KOMPSAT-5 is a low earth orbit (LEO satellite scheduled to be launched in 2010. To satisfy the precision orbit determination (POD requirement for a high resolution synthetic aperture radar image of KOMPSAT-5, KOMPSAT-5 has atmosphere occultation POD (AOPOD system which consists of a space-borne dual frequency global positioning system (GPS receiver and a laser retro reflector array. A space-borne dual frequency GPS receiver on a LEO satellite provides position data for the POD and radio occultation data for scientific applications. This paper describes an overview of AOPOD system and operation concepts of the radio occultation mission in KOMPSAT-5. We showed AOPOD system satisfies the requirements of KOMPSAT-5 in performance and stability.

Lunar occultation of Saturn. IV - Astrometric results from observations of the satellites

Science.gov (United States)

Dunham, D. W.; Elliot, J. L.

1978-01-01

The method of determining local lunar limb slopes, and the consequent time scale needed for diameter studies, from accurate occultation timings at two nearby telescopes is described. Results for photoelectric observations made at Mauna Kea Observatory during the occultation of Saturn's satellites on March 30, 1974, are discussed. Analysis of all observations of occultations of Saturn's satellites during 1974 indicates possible errors in the ephemerides of Saturn and its satellites.

Precise pointing knowledge for SCIAMACHY solar occultation measurements

Directory of Open Access Journals (Sweden)

K. Bramstedt

2012-11-01

Full Text Available We present a method to precisely determine the viewing direction for solar occultation instruments from scans over the solar disk. Basic idea is the fit of the maximum intensity during the scan, which corresponds to the center of the solar disk in the scanning direction. We apply this method to the solar occultation measurements of the satellite instrument SCIAMACHY, which scans the Sun in elevation direction. The achieved mean precision is 0.46 mdeg, which corresponds to an tangent height error of about 26 m for individual occultation sequences. The deviation of the derived elevation angle from the geolocation information given along with the product has a seasonal cycle with an amplitude of 2.26 mdeg, which is in tangent height an amplitude of about 127 m. The mean elevation angle offset is −4.41 mdeg (249 m. SCIAMACHY's sun follower device controls the azimuth viewing direction during the occultation measurements. The derived mean azimuth direction has an standard error of 0.65 mdeg, which is about 36 m in horizontal direction at the tangent point. We observe also a seasonal cycle of the azimuth mispointing with an amplitude of 2.3 mdeg, which is slightly increasing with time. The almost constant mean offset is 88 mdeg, which is about 5.0 km horizontal offset at the tangent point.

Scaled model guidelines for solar coronagraphs' external occulters with an optimized shape.

Science.gov (United States)

Landini, Federico; Baccani, Cristian; Schweitzer, Hagen; Asoubar, Daniel; Romoli, Marco; Taccola, Matteo; Focardi, Mauro; Pancrazzi, Maurizio; Fineschi, Silvano

2017-12-01

One of the major challenges faced by externally occulted solar coronagraphs is the suppression of the light diffracted by the occulter edge. It is a contribution to the stray light that overwhelms the coronal signal on the focal plane and must be reduced by modifying the geometrical shape of the occulter. There is a rich literature, mostly experimental, on the appropriate choice of the most suitable shape. The problem arises when huge coronagraphs, such as those in formation flight, shall be tested in a laboratory. A recent contribution [Opt. Lett.41, 757 (2016)OPLEDP0146-959210.1364/OL.41.000757] provides the guidelines for scaling the geometry and replicate in the laboratory the flight diffraction pattern as produced by the whole solar disk and a flight occulter but leaves the conclusion on the occulter scale law somehow unjustified. This paper provides the numerical support for validating that conclusion and presents the first-ever simulation of the diffraction behind an occulter with an optimized shape along the optical axis with the solar disk as a source. This paper, together with Opt. Lett.41, 757 (2016)OPLEDP0146-959210.1364/OL.41.000757, aims at constituting a complete guide for scaling the coronagraphs' geometry.

Tight closure and vanishing theorems

International Nuclear Information System (INIS)

Smith, K.E.

2001-01-01

Tight closure has become a thriving branch of commutative algebra since it was first introduced by Mel Hochster and Craig Huneke in 1986. Over the past few years, it has become increasingly clear that tight closure has deep connections with complex algebraic geometry as well, especially with those areas of algebraic geometry where vanishing theorems play a starring role. The purpose of these lectures is to introduce tight closure and to explain some of these connections with algebraic geometry. Tight closure is basically a technique for harnessing the power of the Frobenius map. The use of the Frobenius map to prove theorems about complex algebraic varieties is a familiar technique in algebraic geometry, so it should perhaps come as no surprise that tight closure is applicable to algebraic geometry. On the other hand, it seems that so far we are only seeing the tip of a large and very beautiful iceberg in terms of tight closure's interpretation and applications to algebraic geometry. Interestingly, although tight closure is a 'characteristic p' tool, many of the problems where tight closure has proved useful have also yielded to analytic (L2) techniques. Despite some striking parallels, there had been no specific result directly linking tight closure and L∼ techniques. Recently, however, the equivalence of an ideal central to the theory of tight closure was shown to be equivalent to a certain 'multiplier ideal' first defined using L2 methods. Presumably, deeper connections will continue to emerge. There are two main types of problems for which tight closure has been helpful: in identifying nice structure and in establishing uniform behavior. The original algebraic applications of tight closure include, for example, a quick proof of the Hochster-Roberts theorem on the Cohen-Macaulayness of rings of invariants, and also a refined version of the Brianqon-Skoda theorem on the uniform behaviour of integral closures of powers of ideals. More recent, geometric

Diagnostic accuracy of oblique chest radiograph for occult pneumothorax: comparison with ultrasonography

OpenAIRE

Matsumoto, Shokei; Sekine, Kazuhiko; Funabiki, Tomohiro; Orita, Tomohiko; Shimizu, Masayuki; Hayashida, Kei; Kazamaki, Taku; Suzuki, Tatsuya; Kishikawa, Masanobu; Yamazaki, Motoyasu; Kitano, Mitsuhide

2016-01-01

Backgraound An occult pneumothorax is a pneumothorax that is not seen on a supine chest X-ray but is detected by computed tomography scanning. However, critical patients are difficult to transport to the computed tomography suite. We previously reported a method to detect occult pneumothorax using oblique chest radiography (OXR). Several authors have also reported that ultrasonography is an effective technique for detecting occult pneumothorax. The aim of this study was to evaluate the useful...

Occult HBV infection in HIV-infected adults and evaluation of pooled NAT for HBV.

Science.gov (United States)

Dinesha, T R; Boobalan, J; Sivamalar, S; Subashini, D; Solomon, S S; Murugavel, K G; Balakrishnan, P; Smith, D M; Saravanan, S

2018-01-06

The study aimed to determine the prevalence of occult hepatitis B virus infection among HIV-infected persons and to evaluate the use of a pooling strategy to detect occult HBV infection in the setting of HIV infection. Five hundred and two HIV-positive individuals were tested for HBV, occult HBV and hepatitis C and D with serologic and nucleic acid testing (NAT). We also evaluated a pooled NAT strategy for screening occult HBV infection among the HIV-positive individuals. The prevalence of HBV infection among HIV-positive individuals was 32 (6.4%), and occult HBV prevalence was 10%. The pooling HBV NAT had a sensitivity of 66.7% and specificity of 100%, compared to HBV DNA NAT of individual samples. In conclusion, this study found a high prevalence of occult HBV infection among our HIV-infected population. We also demonstrated that pooled HBV NAT is highly specific, moderately sensitive and cost-effective. As conventional HBV viral load assays are expensive in resource-limited settings such as India, pooled HBV DNA NAT might be a good way for detecting occult HBV infection and will reduce HBV-associated complications. © 2018 John Wiley & Sons Ltd.

David Levy's Guide to Eclipses, Transits, and Occultations

Science.gov (United States)

Levy, David H.

2010-08-01

Introduction; Part I. The Magic and History of Eclipses: 1. Shakespeare, King Lear, and the Great Eclipse of 1605; 2. Three centuries later: Einstein, relativity, and the solar eclipse of 1919; 3. What causes solar and lunar eclipses; Part II. Observing Solar Eclipses: 4. Safety considerations; 5. What to expect during a partial eclipse; 6. Annular eclipses and what to see in them; 7. Total eclipse of the Sun: introduction to the magic; 8. The onset: temperature drop, Baily's Beads, Diamond Ring; 9. Totality: Corona, Prominences, Chromosphere, and surrounding area; 10. Photographing and imaging a solar eclipse; Part III. Observing Lunar Eclipses: 11. Don't forget the penumbral eclipses!; 12. Partial lunar eclipses; 13. Total lunar eclipses; 14. Photographing and imaging lunar eclipses; Part IV. Occultations: 15. When the Moon occults a star; Part V. Transits: 16. When planets cross the Sun; Part VI. My Favorite Eclipses: 17. A personal canon of eclipses, occultations, and transits I have seen; Appendices; Index.

Sensing Water Vapon via Spacecraft Radio Occultation Observations

Science.gov (United States)

Kursinski, E. Robert; Hajj, George A.

2000-01-01

The radio occultation technique has been used to characterize planetary atmospheres since the 1960's spanning atmospheric pressures from 16 microbars to several bars. In 1988, the use of GPS signals to make occultation observations of Earth's atmosphere was realized by Tom Yunck and Gunnar Lindal at JPL. In the GPS to low-Earth-orbiter limb- viewing occultation geometry, Fresnel diffraction yield a unique combination of high vertical resolution of 100 m to 1 km at long wavelengths (approx. 20 cm) insensitive to particulate scattering which allows routine limb sounding from the lower mesosphere through the troposphere. A single orbiting GPS/GLONASS receiver can observe - 1000 to 1400 daily occultations providing as many daily, high vertical resolution soundings as the present global radiosonde network, but with far more evenly distributed, global coverage. The occultations yield profiles of refractivity as a function of height. In the cold, dry conditions of the upper troposphere and above (T less than 240 K), profiles of density, pressure (geopotential), and temperature can be derived. Given additional temperature information, water vapor can be derived in the midddle and lower troposphere with a unique combination of vertical resolution, global distribution and insensitivity to clouds and precipitation to an accuracy of approx. 0.2 g/kg. At low latitudes, moisture profiles will be accurate to 1-5% within the convective boundary layer and better than 20% below 6 to 7 km. Accuracies of climatological averages should be approx. 0. 1 g/kg limited by the biases in the temperature estimates. To use refractivity to constrain water vapor, knowledge of temperature is required. The simplest approach is to use the temperature field from an analysis such as the 6 hour ECMWF global analysis interpolated to the locations of each occultation. A better approach is to combine the temperature and moisture fields from such an analysis with the occultation refractivity in a weighting

Occult pneumothorax, revisited

OpenAIRE

Mangar Devanand; Abdelmalak Hany; Omar Hesham R; Rashad Rania; Helal Engy; Camporesi Enrico M

2010-01-01

Abstract Pneumothorax is a recognized cause of preventable death following chest wall trauma where a simple intervention can be life saving. In cases of trauma patients where cervical spine immobilization is mandatory, supine AP chest radiograph is the most practical initial study. It is however not as sensitive as CT chest for early detection of a pneumothorax. "Occult" pneumothorax is an accepted definition of an existing but usually a clinically and radiologically silent disturbance that i...

Occurrence of occult CSF leaks during standard FESS procedures.

Science.gov (United States)

Bucher, S; Kugler, A; Probst, E; Epprecht, L; Stadler, R S; Holzmann, D; Soyka, M B

2018-03-18

To determine the incidence of occult cerebrospinal fluid leaks (CSF) after functional endoscopic sinus surgery (FESS) and to evaluate the diagnostic performance of beta2-transferrin in blood-contaminated conditions. Prospective cohort study. An analysis of 57 intraoperative samples using hydrogel 6 beta2-transferrin assay after FESS was undertaken. In case of CSF positive samples and continuing rhinorrhea, reanalysis after more than 1 year was conducted. In-vivo analysis of a primary spontaneous CSF leak sample took place to verify difficulties in detecting beta2-transferrin in blood-contaminated settings. Own titrations were performed to evaluate detection limits of CSF by beta2-transferrin and beta-trace protein assays in these settings. An incidence of 13% for occult CSF leaks after FESS was found. In blood-contaminated conditions, routine beta2-transferrin assays showed low sensitivity. In over 1 year follow-up, all samples were negative for CSF and none of them developed clinical relevant CSF leaks or meningitis. Occult and clinically irrelevant CSF leaks do occur in a significant proportion of patients during and shortly after FESS. Intra- and postoperatively, routine beta2-transferrin assays show low sensitivity. They should not be used in these settings. The clinical course of patients with occult CSF leaks indicated possibility of an uneventful follow-up.

MR imaging evaluation of congenital malformation of the spine

International Nuclear Information System (INIS)

Byrd, S.E.; Radkowski, M.A.; McLone, D.G.; Storrs, B.B.

1988-01-01

One hundred fifty children with congenital malformations of the spine were studied with MR imaging, US, and water-soluble myelography with CT. The malformations encountered included myelomeningoceles and Chiari II malformations, diastematomyelia, hydromyelia, arachnoid cyst, dermal sinus and dermoid, spinal lipomas and teratomas, tight filum terminale, anterior sacral meningoceles, lipomyelomeningoceles, myelocystocele, and severe scoliosis. MR imaging was the most effective modality in delineating these abnormalities. At times, real-time US and water-soluble CT myelography were required as adjuncts to MR imaging in delineating subtle spinal cord tethering, arachnoid cyst, diastematomyelia, and severe scoliosis

Optimization of the occulter for the Solar Orbiter/METIS coronagraph

Science.gov (United States)

Landini, Federico; Vivès, Sébastien; Romoli, Marco; Guillon, Christophe; Pancrazzi, Maurizio; Escolle, Clement; Focardi, Mauro; Antonucci, Ester; Fineschi, Silvano; Naletto, Giampiero; Nicolini, Gianalfredo; Nicolosi, Piergiorgio; Spadaro, Daniele

2012-09-01

METIS (Multi Element Telescope for Imaging and Spectroscopy investigation), selected to fly aboard the Solar Orbiter ESA/NASA mission, is conceived to perform imaging (in visible, UV and EUV) and spectroscopy (in EUV) of the solar corona, by means of an integrated instrument suite located on a single optical bench and sharing the same aperture on the satellite heat shield. As every coronagraph, METIS is highly demanding in terms of stray light suppression. Coronagraphs history teaches that a particular attention must be dedicated to the occulter optimization. The METIS occulting system is of particular interest due to its innovative concept. In order to meet the strict thermal requirements of Solar Orbiter, METIS optical design has been optimized by moving the entrance pupil at the level of the external occulter on the S/C thermal shield, thus reducing the size of the external aperture. The scheme is based on an inverted external-occulter (IEO). The IEO consists of a circular aperture on the Solar Orbiter thermal shield. A spherical mirror rejects back the disk-light through the IEO. A breadboard of the occulting assembly (BOA) has been manufactured in order to perform stray light tests in front of two solar simulators (in Marseille, France and in Torino, Italy). A first measurement campaign has been carried on at the Laboratoire d'Astrophysique de Marseille. In this paper we describe the BOA design, the laboratory set-up and the preliminary results.

Radioimmune localization of occult carcinoma

International Nuclear Information System (INIS)

Duda, R.B.; Zimmer, A.M.; Rosen, S.T.; Gilyon, K.A.; Webber, D.; Spies, S.; Spies, W.; Merchant, B.

1990-01-01

Patients with a rising serum carcinoembryonic antigen level and no clinical or roentgenographic evidence of recurrent or metastatic cancer present a treatment dilemma. Eleven such patients, 10 with a previously treated colorectal carcinoma and 1 with a previously treated breast carcinoma, received an injection of the anticarcinoembryonic antigen monoclonal antibody ZCE-025 labeled with the radioisotope indium 111. Nuclear scintigraphy was performed on days 3 and 5 through 7 to detect potential sites of tumor recurrence. The monoclonal antibody scan accurately predicted the presence or absence of occult malignancy in 7 (64%) patients. Second-look laparotomy confirmed the monoclonal antibody scan results in the patients with colorectal cancer, and magnetic resonance imaging confirmed metastatic breast cancer. This study demonstrates that In-ZCE-025 can localize occult carcinoma and may assist the surgeon in facilitating the operative exploration. In-ZCE-025 assisted in the initiation of adjuvant therapy for the patient with breast cancer

Tight junctions and human diseases.

Science.gov (United States)

Sawada, Norimasa; Murata, Masaki; Kikuchi, Keisuke; Osanai, Makoto; Tobioka, Hirotoshi; Kojima, Takashi; Chiba, Hideki

2003-09-01

Tight junctions are intercellular junctions adjacent to the apical end of the lateral membrane surface. They have two functions, the barrier (or gate) function and the fence function. The barrier function of tight junctions regulates the passage of ions, water, and various macromolecules, even of cancer cells, through paracellular spaces. The barrier function is thus relevant to edema, jaundice, diarrhea, and blood-borne metastasis. On the other hand, the fence function maintains cell polarity. In other words, tight junctions work as a fence to prevent intermixing of molecules in the apical membrane with those in the lateral membrane. This function is deeply involved in cancer cell biology, in terms of loss of cell polarity. Of the proteins comprising tight junctions, integral membrane proteins occludin, claudins, and JAMs have been recently discovered. Of these molecules, claudins are exclusively responsible for the formation of tight-junction strands and are connected with the actin cytoskeleton mediated by ZO-1. Thus, both functions of tight junctions are dependent on the integrity of the actin cytoskeleton as well as ATP. Mutations in the claudin14 and the claudin16 genes result in hereditary deafness and hereditary hypomagnesemia, respectively. Some pathogenic bacteria and viruses target and affect the tight-junction function, leading to diseases. In this review, the relationship between tight junctions and human diseases is summarized.

James Webb Space Telescope Observations of Stellar Occultations by Solar System Bodies and Rings

Science.gov (United States)

Santos-Sanz, P.; French, R. G.; Pinilla-Alonso, N.; Stansberry, J.; Lin, Z-Y.; Zhang, Z-W.; Vilenius, E.; Mueller, Th.; Ortiz, J. L.; Braga-Ribas, F.;

Recurring sets of recurring starspot occultations on exoplanet host Qatar-2

Science.gov (United States)

Močnik, T.; Southworth, J.; Hellier, C.

2017-10-01

We announce the detection of recurring sets of recurring starspot occultation events in the short-cadence K2 light curve of Qatar-2, a K dwarf star transited every 1.34 d by a hot Jupiter. In total, we detect 34 individual starspot occultation events, caused by five different starspots, occulted in up to five consecutive transits or after a full stellar rotation. The longest recurring set of recurring starspot occultations spans over three stellar rotations, setting a lower limit for the longest starspot lifetime of 58 d. Starspot analysis provided a robust stellar rotational period measurement of 18.0 ± 0.2 d and indicates that the system is aligned, having a sky-projected obliquity of 0° ± 8°. A pronounced rotational modulation in the light curve has a period of 18.2 ± 1.6 d, in agreement with the rotational period derived from the starspot occultations. We tentatively detect an ellipsoidal modulation in the phase curve, with a semi-amplitude of 18 ppm, but cannot exclude the possibility that this is the result of red noise or imperfect removal of the rotational modulation. We detect no transit-timing and transit-duration variations with upper limits of 15 s and 1 min, respectively. We also reject any additional transiting planets with transit depths above 280 ppm in the orbital period region 0.5-30 d.

A method to detect occult pneumothorax with chest radiography.

Science.gov (United States)

Matsumoto, Shokei; Kishikawa, Masanobu; Hayakawa, Koichi; Narumi, Atsushi; Matsunami, Katsutoshi; Kitano, Mitsuhide

2011-04-01

Small pneumothoraces are often not visible on supine screening chest radiographs because they develop anteriorly to the lung. These pneumothoraces are termed occult. Occult pneumothoraces account for an astonishingly high 52% to 63% of all traumatic pneumothoraces. A 19-year-old obese woman was involved in a head-on car accident. The admission anteroposterior chest radiographs were unremarkable. Because of the presence of right chest tenderness and an abrasion, we suspected the presence of a pneumothorax. Thus, we decided to take a supine oblique chest radiograph of the right side of the thorax, which clearly revealed a visceral pleural line, consistent with a diagnosis of traumatic pneumothorax. A pneumothorax may be present when a supine chest radiograph reveals either an apparent deepening of the costophrenic angle (the "deep sulcus sign") or the presence of 2 diaphragm-lung interfaces (the "double diaphragm sign"). However, in practice, supine chest radiographs have poor sensitivity for occult pneumothoraces. Oblique chest radiograph is a useful and fast screening tool that should be considered for cases of blunt chest trauma, especially when transport of critically ill patients to the computed tomographic suite is dangerous or when imminent transfer to another hospital is being arranged and early diagnosis of an occult pneumothorax is essential. Copyright © 2010 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.

Ultrasound detection of nonpalpable mammographically occult malignancy

International Nuclear Information System (INIS)

Simpson, W.L.; Hermann, G.; Rausch, D.R.; Sherman, J.; Feig, S.A.; Bleiweiss, I.J.; Jaffer, S.

2008-01-01

To evaluate the prevalence of occult malignancy with screening breast ultrasound. All ultrasound-guided core needle breast biopsies performed between January 1, 1999, and June 30, 2001, were retrospectively reviewed. Lesions were identified during screening breast ultrasound in high-risk women with no mammographic or palpable abnormality in either breast, a unilateral mammographic or palpable abnormality in the contralateral breast, or a unilateral mammographic or palpable abnormality in a different quadrant of the same breast. All ultrasound-detected lesions were histologically verified. Six hundred and fifty-two women with a mean age of 49 years underwent 698 biopsies during the study period. Three hundred and forty-nine of these lesions were detected at screening breast ultrasound. Out of 349, 11 (3.2%) had a mammographically and clinically occult malignancy. Nine cancers were found in women with no mammographic or palpable abnormality. Two cancers were found in the same breast as the mammographic or palpable abnormality. None were found in the breast contralateral to a palpable or mammographic abnormality. Screening breast ultrasound of high-risk women has a similar detection rate for occult carcinoma as screening mammography, but has a low positive predictive value in cases where biopsy is performed. (author)

Presentation of Axillary Metastases from Occult Breast Carcinoma

Institute of Scientific and Technical Information of China (English)

Xin Wang

2007-01-01

Axillary presentation from occult breast cancer is uncommon and continues to be a diagnostic and therapeutic challenge to physicians.Once the diagnosis of adenocarcinoma metastatic to an axillary lymph node has been confirmed,a preoperative workup should be done.The current experience is based on several relatively small retrospective reviews and case reports.It is difficult to determine the best management of occult breast cancer.However,treatmenl of axillary Iymph node dissection is recommended for local control and complete staging information.Treatment of breast should be a choice between breast conservation with whole-breast radiotherapy and mastectomy.Adjuvant systemic treatment should be offered.

Developing an Optical Lunar Occultation Measurement Reduction System for Observations at Kaau Observatory

Science.gov (United States)

Malawi, Abdulrahman A.

2013-06-01

We present here a detailed explanation of the reduction method that we use to determine the angular diameters of the stars occulted by the dark limb of the moon. This is a main part of the lunar occultation observation program running at King Abdul Aziz University observatory since late 1993. The process is based on the least square model fitting method of analyzing occultation data, first introduced by Nather et al. (Astron. J. 75:963, 1970).

[Surgical Diagnosis and Treatment of Primary Hyperthyroidism Complicated with Occult Thyroid Carcinoma].

Science.gov (United States)

Wu, Xin; Yu, Jian-chun; Kang, Wei-ming; Ma, Zhi-qiang; Ye, Xin

2015-08-01

To evaluate the surgical diagnosis and treatment of primary hyperthyroidism complicated with occult thyroid carcinoma. Data of 51 cases of primary hyperthyroidism complicated with occult thyroid carcinoma admitted during January 2004 to November 2014 were analyzed retrospectively. The incidence of occult thyroid carcinoma was 5.03% in hyperthyroidism,and 47 cases (92.16%) were female. The preoperative diagnosis of all these 51 cases was primary hyperthyroidism and 11 cases were diagnosed thyroid carcinoma at the same time;25 cases were diagnosed thyroid carcinoma by frozen section and the remaining 26 cases were diagnosed by postoperative pathology. Finally,26 cases underwent subtotal thyroidectomy,4 cases underwent total thyroidectomy, and 21 cases underwent total thyroidectomy with lymphadenectomy. The tumor size ranged from 0.1 to 1.0 cm [mean:(0.63 ± 0.35) cm]. The lesions were less than or equal to 0.5 cm in 28 cases (54.9%). The follow-up lasted from 1 to 121 months [mean:(28.6 ± 22.7)months] in 43 patients,and all of them survived. Primary hyperthyroidism complicated with occult thyroid carcinoma is commonly found in female patients. Preoperative diagnosis is difficult. Ultrasound is the major examining method. Frozen section can increase the detection rate. The postoperative prognosis of hyperthyroidism complicated with occult thyroid carcinoma is satisfactory.

Occult fractures of the knee: tomographic evaluation

International Nuclear Information System (INIS)

Apple, J.S.; Martinez, S.; Allen, N.B.; Caldwell, D.S.; Rice, J.R.

1983-01-01

Seven adults with painful effusions of the knee were examined for occult fractures using pluridirectional tomograph in the coronal and lateral planes. Six patients (ages 50 to 82 years) were osteopenic and gave histories ranging from none to mild trauma; one 26-year-old man was not osteopenic and had severe trauma. In all cases, routine radiographs were interpreted as negative, but tomography demonstrated a fracture. Five fractures were subchondral. Bone scans in 2 patients were positive. The authors conclude that osteopenic patients with a painful effusion of the knee should be considered to have an occult fracture. While bone scans may be helpful, tomography is recommended as the procedure of choice to define the location and extent of the fracture

Dusty Dwarfs Galaxies Occulting A Bright Background Spiral

Science.gov (United States)

Holwerda, Benne

2017-08-01

The role of dust in shaping the spectral energy distributions of low mass disk galaxies remains poorly understood. Recent results from the Herschel Space Observatory imply that dwarf galaxies contain large amounts of cool (T 20K) dust, coupled with very modest optical extinctions. These seemingly contradictory conclusions may be resolved if dwarfs harbor a variety of dust geometries, e.g., dust at larger galactocentric radii or in quiescent dark clumps. We propose HST observations of six truly occulting dwarf galaxies drawn from the Galaxy Zoo catalog of silhouetted galaxy pairs. Confirmed, true occulting dwarfs are rare as most low-mass disks in overlap are either close satellites or do not have a confirmed redshift. Dwarf occulters are the key to determining the spatial extent of dust, the small scale structure introduced by turbulence, and the prevailing dust attenuation law. The recent spectroscopic confirmation of bona-fide low mass occulting dwarfs offers an opportunity to map dust in these with HST. What is the role of dust in the SED of these dwarf disk galaxies? With shorter feedback scales, how does star-formation affect their morphology and dust composition, as revealed from their attenuation curve? The resolution of HST allows us to map the dust disks down to the fine scale structure of molecular clouds and multi-wavelength imaging maps the attenuation curve and hence dust composition in these disks. We therefore ask for 2 orbits on each of 6 dwarf galaxies in F275W, F475W, F606W, F814W and F125W to map dust from UV to NIR to constrain the attenuation curve.

Estimation and evaluation of COSMIC radio occultation excess phase using undifferenced measurements

Science.gov (United States)

Xia, Pengfei; Ye, Shirong; Jiang, Kecai; Chen, Dezhong

2017-05-01

In the GPS radio occultation technique, the atmospheric excess phase (AEP) can be used to derive the refractivity, which is an important quantity in numerical weather prediction. The AEP is conventionally estimated based on GPS double-difference or single-difference techniques. These two techniques, however, rely on the reference data in the data processing, increasing the complexity of computation. In this study, an undifferenced (ND) processing strategy is proposed to estimate the AEP. To begin with, we use PANDA (Positioning and Navigation Data Analyst) software to perform the precise orbit determination (POD) for the purpose of acquiring the position and velocity of the mass centre of the COSMIC (The Constellation Observing System for Meteorology, Ionosphere and Climate) satellites and the corresponding receiver clock offset. The bending angles, refractivity and dry temperature profiles are derived from the estimated AEP using Radio Occultation Processing Package (ROPP) software. The ND method is validated by the COSMIC products in typical rising and setting occultation events. Results indicate that rms (root mean square) errors of relative refractivity differences between undifferenced and atmospheric profiles (atmPrf) provided by UCAR/CDAAC (University Corporation for Atmospheric Research/COSMIC Data Analysis and Archive Centre) are better than 4 and 3 % in rising and setting occultation events respectively. In addition, we also compare the relative refractivity bias between ND-derived methods and atmPrf profiles of globally distributed 200 COSMIC occultation events on 12 December 2013. The statistical results indicate that the average rms relative refractivity deviation between ND-derived and COSMIC profiles is better than 2 % in the rising occultation event and better than 1.7 % in the setting occultation event. Moreover, the observed COSMIC refractivity profiles from ND processing strategy are further validated using European Centre for Medium

Occult Carbon Monoxide Poisoning

OpenAIRE

Kirkpatrick, John N.

1987-01-01

A syndrome of headache, fatigue, dizziness, paresthesias, chest pain, palpitations and visual disturbances was associated with chronic occult carbon monoxide exposure in 26 patients in a primary care setting. A causal association was supported by finding a source of carbon monoxide in a patient's home, workplace or vehicle; results of screening tests that ruled out other illnesses; an abnormally high carboxyhemoglobin level in 11 of 14 patients tested, and abatement or resolution of symptoms ...

Detection of occult abscesses with 111In-labeled leukocytes

International Nuclear Information System (INIS)

Martin, W.R.; Gurevich, N.; Goris, M.L.; McDougall, I.R.

1979-01-01

Clinicians are frequently faced with the problem of a patient in whom they suspect an occult abscess. In such a situation, there may be no clinical signs to localize the site of the abscess and often extensive investigations do not provide additional useful information. This report illustrates the efficacy of autologous leukocytes labeled with 111 In oxine in detecting the site and extent of occult abscesses in two patients. The technique of in vitro lebeling of leukocytes is simple and has been mastered by all of our nuclear medicine technologists

A prospective evaluation of occult disorders in obstructed defecation using the 'iceberg diagram'.

Science.gov (United States)

Pescatori, M; Spyrou, M; Pulvirenti d'Urso, A

2007-06-01

Surgical treatment of constipation and obstructed defecation (OD) carries frequent recurrences, as OD is an 'iceberg syndrome' characterized by 'underwater rocks' or occult diseases which may affect the outcome of surgery. The aim of this study was to evaluate occult disorders, in order to alert the clinician of these and minimize failures. One hundred consecutive constipated patients with OD symptoms, 81 women, median age 52 years, underwent perineal examination, proctoscopy, anorectal manometry and anal/vaginal ultrasound (US). Anorectal physiology and imaging tests were also carried out when indicated, as well as psychological and urogynaecological consultations. Symptoms were graded using a modified 1-20 constipation score. Both evident (e.g. rectocele) and occult (e.g. anismus) diseases were prospectively evaluated using a novel 'iceberg diagram'. The type of treatment, whether conservative or surgical, was also recorded. Fifty-four (54%) patients had both mucosal prolapse and rectocele. All patients had at least two occult OD-related diseases, 66 patients had at least three of them: anxiety-depression, anismus and rectal hyposensation were the most frequent (66%, 44% and 33%, respectively). The median constipation score was 11 (range 2-20), the median number of 'occult disorders' was 5 (range 2-8). Conservative treatment was carried out in most cases. Surgery was carried out in 14 (14%) patients. The novel 'iceberg diagram' allowed the adequate evaluation of OD-related occult diseases and better selection of patients for treatment. Most were managed conservatively, and only a minority were treated by surgery.

Error analysis for mesospheric temperature profiling by absorptive occultation sensors

Directory of Open Access Journals (Sweden)

M. J. Rieder

Full Text Available An error analysis for mesospheric profiles retrieved from absorptive occultation data has been performed, starting with realistic error assumptions as would apply to intensity data collected by available high-precision UV photodiode sensors. Propagation of statistical errors was investigated through the complete retrieval chain from measured intensity profiles to atmospheric density, pressure, and temperature profiles. We assumed unbiased errors as the occultation method is essentially self-calibrating and straight-line propagation of occulted signals as we focus on heights of 50–100 km, where refractive bending of the sensed radiation is negligible. Throughout the analysis the errors were characterized at each retrieval step by their mean profile, their covariance matrix and their probability density function (pdf. This furnishes, compared to a variance-only estimation, a much improved insight into the error propagation mechanism. We applied the procedure to a baseline analysis of the performance of a recently proposed solar UV occultation sensor (SMAS – Sun Monitor and Atmospheric Sounder and provide, using a reasonable exponential atmospheric model as background, results on error standard deviations and error correlation functions of density, pressure, and temperature profiles. Two different sensor photodiode assumptions are discussed, respectively, diamond diodes (DD with 0.03% and silicon diodes (SD with 0.1% (unattenuated intensity measurement noise at 10 Hz sampling rate. A factor-of-2 margin was applied to these noise values in order to roughly account for unmodeled cross section uncertainties. Within the entire height domain (50–100 km we find temperature to be retrieved to better than 0.3 K (DD / 1 K (SD accuracy, respectively, at 2 km height resolution. The results indicate that absorptive occultations acquired by a SMAS-type sensor could provide mesospheric profiles of fundamental variables such as temperature with

Error analysis for mesospheric temperature profiling by absorptive occultation sensors

Directory of Open Access Journals (Sweden)

M. J. Rieder

2001-01-01

Full Text Available An error analysis for mesospheric profiles retrieved from absorptive occultation data has been performed, starting with realistic error assumptions as would apply to intensity data collected by available high-precision UV photodiode sensors. Propagation of statistical errors was investigated through the complete retrieval chain from measured intensity profiles to atmospheric density, pressure, and temperature profiles. We assumed unbiased errors as the occultation method is essentially self-calibrating and straight-line propagation of occulted signals as we focus on heights of 50–100 km, where refractive bending of the sensed radiation is negligible. Throughout the analysis the errors were characterized at each retrieval step by their mean profile, their covariance matrix and their probability density function (pdf. This furnishes, compared to a variance-only estimation, a much improved insight into the error propagation mechanism. We applied the procedure to a baseline analysis of the performance of a recently proposed solar UV occultation sensor (SMAS – Sun Monitor and Atmospheric Sounder and provide, using a reasonable exponential atmospheric model as background, results on error standard deviations and error correlation functions of density, pressure, and temperature profiles. Two different sensor photodiode assumptions are discussed, respectively, diamond diodes (DD with 0.03% and silicon diodes (SD with 0.1% (unattenuated intensity measurement noise at 10 Hz sampling rate. A factor-of-2 margin was applied to these noise values in order to roughly account for unmodeled cross section uncertainties. Within the entire height domain (50–100 km we find temperature to be retrieved to better than 0.3 K (DD / 1 K (SD accuracy, respectively, at 2 km height resolution. The results indicate that absorptive occultations acquired by a SMAS-type sensor could provide mesospheric profiles of fundamental variables such as temperature with

Influence of misalignments on the performance of externally occulted solar coronagraphs. Application to PROBA-3/ASPIICS

Science.gov (United States)

Shestov, S. V.; Zhukov, A. N.

2018-05-01

Context. The ASPIICS instrument is a novel externally occulted coronagraph that will be launched on board the PROBA-3 mission of the European Space Agency. The external occulter will be placed on one satellite 150 m ahead of the second satellite that will carry an optical instrument. During 6 h out of 19.38 h of orbit, the satellites will fly in a precise (accuracy around a few millimeters) formation, constituting a giant externally occulted coronagraph. The large distance between the external occulter and the primary objective will allow observations of the white-light solar corona starting from extremely low heights 1.1R⊙. Aims: We intend to analyze influence of shifts of the satellites and misalignments of optical elements on the ASPIICS performance in terms of diffracted light. Based on the quantitative influence of misalignments on diffracted light, we provide a recipe for choosing the size of the internal occulter (IO) to achieve a trade-off between the minimal height of observations and sustainability to possible misalignments. Methods: We considered different types of misalignments and analyzed their influence from optical and computational points of view. We implemented a numerical model of the diffracted light and its propagation through the optical system and computed intensities of diffracted light throughout the instrument. Our numerical approach is based on a model from the literature that considered the axisymmetrical case. Here we extend the model to include nonsymmetrical cases and possible misalignments. Results: The numerical computations fully confirm the main properties of the diffracted light that we obtained from semi-analytical consideration. We obtain that relative influences of various misalignments are significantly different. We show that the internal occulter with RIO = 1.694 mm = 1.1R⊙ is large enough to compensate possible misalignments expected to occur in PROBA-3/ASPIICS. Besides that we show that apodizing the edge of the

Parapsychology on the couch: the psychology of occult belief in Germany, c. 1870-1939.

Science.gov (United States)

Wolffram, Heather

2006-01-01

This article considers the attempts of academic psychologists and critical occultists in Germany during the late nineteenth and early twentieth centuries to construct a psychology of occult belief. While they claimed that the purpose of this new subdiscipline was to help evaluate the work of occult researchers, the emergence of a psychology of occult belief in Germany served primarily to pathologize parapsychology and its practitioners. Not to be outdone, however, parapsychologists argued that their adversaries suffered from a morbid inability to accept the reality of the paranormal. Unable to resolve through experimental means the dispute over who should be allowed to mold the public's understanding of the occult, both sides resorted to defaming their opponent. (c) 2006 Wiley Periodicals, Inc.

Categorizing the Occult: Vodun, Sorcery and Religious Beliefs In Benin

DEFF Research Database (Denmark)

Strandsbjerg, Camilla

2011-01-01

In everyday life in Benin as well as in academic research on the topic, the terms of vodun, witchcraft and the occult are often used in a non distinct way covering quite similar phenomena while at the same time referring to different kinds of beliefs and practices. The problem of understanding...... confronted with this difficulty. Both because the vodun, as a recognized religion in the country - equal to Islam and Christianity - , plays an important role in society as well as in individual life, but also because all area of social life are on one level or another influenced by beliefs and practices...... characterized as witchcraft or occult. Reflecting upon earlier research and particularly on the choice of terminology of the occult in writing on religion and political change in Benin (PhD thesis 2008), this paper seeks to clarify some of the epistemological, academic and historical reasons that have formed...

Naturally occurring mutations in large surface genes related to occult infection of hepatitis B virus genotype C.

Directory of Open Access Journals (Sweden)

Hong Kim

Full Text Available Molecular mechanisms related to occult hepatitis B virus (HBV infection, particularly those based on genotype C infection, have rarely been determined thus far in the ongoing efforts to determine infection mechanisms. Therefore, we aim to elucidate the mutation patterns in the surface open reading frame (S ORF underlying occult infections of HBV genotype C in the present study. Nested PCRs were applied to 624 HBV surface antigen (HBsAg negative Korean subjects. Cloning and sequencing of the S ORF gene was applied to 41 occult cases and 40 control chronic carriers. Forty-one (6.6% of the 624 Korean adults with HBsAg-negative serostatus were found to be positive for DNA according to nested PCR tests. Mutation frequencies in the three regions labeled here as preS1, preS2, and S were significantly higher in the occult subjects compared to the carriers in all cases. A total of two types of deletions, preS1 deletions in the start codon and preS2 deletions as well as nine types of point mutations were significantly implicated in the occult infection cases. Mutations within the "a" determinant region in HBsAg were found more frequently in the occult subjects than in the carriers. Mutations leading to premature termination of S ORF were found in 16 occult subjects (39.0% but only in one subject from among the carriers (2.5%. In conclusion, our data suggest that preS deletions, the premature termination of S ORF, and "a" determinant mutations are associated with occult infections of HBV genotype C among a HBsAg-negative population. The novel mutation patterns related to occult infection introduced in the present study can help to broaden our understanding of HBV occult infections.

Heparin as a pharmacologic intervention to induce positive scintiscan in occult gastrointestinal bleeding

International Nuclear Information System (INIS)

Chaudhuri, T.K.; Brantly, M.

1984-01-01

The value of using heparin as a pharmacologic intervention to induce a positive scintiscan was studied in a patient with chronic occult gastrointestinal bleeding. When all standard diagnostic tests (upper and lower gastrointestinal series, upper and lower endoscopy, and conventional noninterventional Tc-99m RBC imaging) fail to detect and localize gastrointestinal bleeding in a patient who has definite clinical evidence (guaiac positive stool and dropping hemoglobin, hematocrit) of chronic occult gastrointestinal oozing, heparin may be used (with proper precaution) as a last resort to aid in the scintigraphic detection and localization of chronic occult gastrointestinal bleeding

Prevalence of occult hepatitis B virus infection in haemodialysis patients from central Greece

Science.gov (United States)

Mina, Paraskevi; Georgiadou, Sarah P; Rizos, Christos; Dalekos, George N; Rigopoulou, Eirini I

2010-01-01

AIM: To assess the hepatitis B virus (HBV)-DNA and the prevalence of occult HBV infection in end-stage renal failure (ESRF) patients from Central Greece. METHODS: Sera from 366 ESRF patients attending five out of six dialysis units from Central Greece were investigated for HBV-DNA by real-time polymerase chain reaction. Only serum samples with repeatedly detectable HBV-DNA were considered positive. IgG antibodies to hepatitis C virus (anti-HCV) were tested by a third generation enzyme linked immunosorbent assay (ELISA), while IgG antibodies to hepatitis E virus (anti-HEV) were tested by two commercially available ELISAs. RESULTS: HBV-DNA was detected in 15/366 patients (4.1%) and HBsAg in 20/366 (5.5%). The prevalence of occult HBV infection was 0.9% (3/346 HBsAg-negative patients). Occult HBV was not associated with a specific marker of HBV infection or anti-HCV or anti-HEV reactivity. There was no significant difference in HBV-DNA titres, demographic and biochemical features, between patients with occult HBV infection and those with HBsAg-positive chronic HBV infection. CONCLUSION: In central Greece, 4% of ESRF patients had detectable HBV-DNA, though in this setting, the prevalence of occult HBV seems to be very low (0.9%). PMID:20066742

Are tight gas resources overstated?

Energy Technology Data Exchange (ETDEWEB)

Roche, P.

2004-11-01

According to conventional wisdom, North America's tight gas resources are continuous, regional accumulations of water-free methane, trapped in low-permeability rock, and involving very little exploration risk. Backing up conventional wisdom, EnCana Corporation is investing heavily in technology-intensive and capital-intensive tight gas plays in Western Canada and the Rocky Mountain regions of the United States. On the other hand, a recent study in the Greater Green River Basin of southwestern Wyoming says that tight gas resources have been significantly overestimated, by as much as three to five times too high, and the risks of exploration are every bit as high as those for conventional exploration. This study essentially dismisses the whole idea of tight gas, or basin-centred gas as a myth, the authors being firmly convinced that tight gas formations should be viewed as conventional hydrocarbon systems, with the usual risks of exploration. This paper discusses the controversy created by this recent study and the implications for natural gas reserves on a basin and individual company level, and the risks associated with exploration. The views of EnCana Corporation, being the company most heavily involved in tight gas and coalbed methane, and those of John Masters, co-founder of Canadian Hunter Exploration Ltd., and discoverer of the blockbuster Elsmworth tight gas deposit in northeastern Alberta in the mid-1970s, are explained in considerable detail, in an effort to dismiss the doubters. EnCana officials and Masters argue that the points raised by the authors of the Greater Green River study do not hold water: Tight gas or basin gas is a distinct hydrocarbon formation, characterized by low permeability, therefore it is to be expected that the gas will take longer to come out of the ground. Neither is the role of water in basin-centred gas systems the major problem as claimed by the doubters. They also characterize it as imprudent to claim to know what the

First Ionospheric Results From the MAVEN Radio Occultation Science Experiment (ROSE)

Science.gov (United States)

Withers, Paul; Felici, M.; Mendillo, M.; Moore, L.; Narvaez, C.; Vogt, M. F.; Jakosky, B. M.

2018-05-01

Radio occultation observations of the ionosphere of Mars can span the full vertical extent of the ionosphere, in contrast to in situ measurements that rarely sample the main region of the ionosphere. However, most existing radio occultation electron density profiles from Mars were acquired without clear context for the solar forcing or magnetospheric conditions, which presents challenges for the interpretation of these profiles. Here we present 48 ionospheric electron density profiles acquired by the Mars Atmosphere and Volatile EvolutioN mission (MAVEN) Radio Occultation Science Experiment (ROSE) from 5 July 2016 to 27 June 2017 at solar zenith angles of 54° to 101°. Latitude coverage is excellent, and comprehensive context for the interpretation of these profiles is provided by other MAVEN instruments. The profiles show a 9-km increase in ionospheric peak altitude in January 2017 that is associated with a lower atmospheric dust storm, variations in electron densities in the M1 layer that cannot be explained by variations in the solar soft X-ray flux, and topside electron densities that are larger in strongly magnetized regions than in weakly magnetized regions. MAVEN Radio Occultation Science Experiment electron density profiles are publicly available on the NASA Planetary Data System.

Occult hepatitis B virus among the patients with abnormal alanine transaminase.

Science.gov (United States)

Makvandi, Manoochehr; Neisi, Niloofar; Khalafkhany, Davod; Makvandi, Kamyar; Hajiani, Eskandar; Shayesteh, Ali Akbar; Masjedi Zadeh, Abdolrahim; Sina, Amir Hosein; Hamidifard, Mojtaba; Rasti, Mojtaba; Aryan, Ehsan; Ahmadi, Kambiz; Yad Yad, Mohammad Jafar

2014-08-01

The occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the sera or in the liver biopsy and the absence of hepatitis B surface antigen (HBsAg) by serological test. The current study aimed to evaluate the occult HBV infection by polymerase chain reaction (PCR) and determine HBV genotyping among the patients with abnormal alanine transaminase (ALT) in Ahvaz city, Iran. The sera of 120 patients, 54 (45%) females and 66 (55%) males, with abnormal ALT 40-152 IU were collected. All the patients were negative for HBsAg for more than one year. The patients` sera were tested by PCR using primers specified for the S region of HBV. Then the positive PCR products were sequenced to determine HBV genotyping and phylogenic tree. Of these 120 subjects, 12 (10%) patients including 6 (5%) males and 6 (5%) females were found positive for HBV DNA by PCR, which indicated the presence of occult HBV infection among these patients. The sequencing results revealed that genotype D was predominant with sub-genotyping D1 among OBI patients. Occult hepatitis B infection is remarkably prevalent in Ahvaz, Iran, and should be considered as a potential risk factor for the transmission of Hepatitis B Virus throughout the community by the carriers.

Sensitivity of GPS occultation to the stratopause height

DEFF Research Database (Denmark)

Schrøder, Thomas Morville; Ao, Chi; de la Torre Juárez, Manuel

2007-01-01

We scrutinize temperature profiles collected with radio occultation measurement for an imprint of the stratopause. In the retrieval step that integrates bending angle data to atmospheric refractivity, the falloff toward infinite altitude is constrained in a boundary condition with statistical opt...... rate, not isothermal conditions. Keeping the model seed for temperature conversion to subsequent retrieval steps eliminates external information from the deconvolved refractivity. It will help argue for radio occultation as independent vehicle for climate monitoring....... height gradient. On the basis of noise free simulation using a climatology covering all latitudes, seasons, and hours and on the basis of validation against data collected with weather balloons, laser imaging, and limb sounding, we find that adaptation to the fluctuating stratopause is crucial...

Lunar occultation observation of μ Sgr: A progress report

Energy Technology Data Exchange (ETDEWEB)

Jatmiko, A. T. P. [Bosscha Observatory, Institut Teknologi Bandung (Indonesia); Puannandra, G. P.; Hapsari, R. D.; Putri, R. A.; Arifin, Z. M.; Haans, G. K.; Hadiputrawan, I. P. W. [Bosscha Observatory, Institut Teknologi Bandung, Indonesia and Astronomy Study Program, Institut Teknologi Bandung (Indonesia)

2014-03-24

Lunar Occultation (LO) is an event where limb of the Moon passing over a particular heavenly bodies such as stars, asteroids, or planets. In other words, during the event, stars, asteroids and planets are occulted by the Moon. When occulted objects contact the lunar limb, there will be a diffraction fringe(s) which can be measured photometrically, until the signal vanishes into noise. This event will give us a valuable information about binarities (of stars) and/or angular diameters estimation (of stars, planets, asteroids) in milliarcsecond resolution, by fitting with theoretical LO pattern. CCDs are common for LO observation because of its fast read out, and recently are developed for sub-meter class telescope. In this paper, our LO observation attempt of μ Sgr and its progress report are presented. The observation was conducted on July 30{sup th}, 2012 at Bosscha Observatory, Indonesia, using 45cm f/12 GOTO telescope combined with ST-9 XE CCD camera and Bessel B filter. We used drift-scan method to obtain light curve of the star as it was disappearing behind Moon's dark limb. Our goal is to detect binarity (or multiplicity) of this particular object.

Occult pneumothorax in trauma patients: should this be sought in the focused assessment with sonography for trauma examination?

Science.gov (United States)

Tam, Michael M K

2005-01-01

At present, CT scan is the gold standard for detecting occult traumatic pneumothorax not apparent on supine chest X-ray radiograph. Recently there were suggestions to expand focused assessment with sonography for trauma (FAST) to include thoracic ultrasound for detecting pneumothorax. The aim of the present study is to determine the incidence of occult pneumothorax (as shown by CT) in the subgroup of trauma patients undergoing FAST. Review of all trauma patients with FAST done from 1 June 2001 to 31 October 2002. Incidence of occult pneumothorax as diagnosed by CT was determined. Patients were not counted as having true occult pneumothorax if they had chest drains inserted before arrival or imaging studies. Selected clinical findings were tested for association with occult pneumothorax. In total, 143 patients underwent FAST, of whom 137 (95.8%) had chest X-ray examination performed. Of the 137 patients 59 required CT abdomen and/or thorax. Occult pneumothorax was found in three patients (2.1%). A history of thorax and/or abdominal injury plus one or more of: (i) mechanisms potentially causing major trauma; (ii) abnormal chest examination; and (iii) chest X-ray radiograph abnormality in the absence of pneumothorax, was significantly associated with the presence of occult pneumothorax (P = 0.03, Fisher's exact test; sensitivity: 100%; specificity: 71%; likelihood ratio: 3.42). The incidence of occult pneumothorax in the subgroup of trauma patients undergoing FAST is low. It implies that routine screening for its presence by adding thoracic ultrasound to FAST is unnecessary. Identifying those at risk of occult pneumothorax for further investigation appeared feasible.

Amplification and protein overexpression of cyclin D1: Predictor of occult nodal metastasis in early oral cancer.

Science.gov (United States)

Noorlag, Rob; Boeve, Koos; Witjes, Max J H; Koole, Ronald; Peeters, Ton L M; Schuuring, Ed; Willems, Stefan M; van Es, Robert J J

2017-02-01

Accurate nodal staging is pivotal for treatment planning in early (stage I-II) oral cancer. Unfortunately, current imaging modalities lack sensitivity to detect occult nodal metastases. Chromosomal region 11q13, including genes CCND1, Fas-associated death domain (FADD), and CTTN, is often amplified in oral cancer with nodal metastases. However, evidence in predicting occult nodal metastases is limited. In 158 patients with early tongue and floor of mouth (FOM) squamous cell carcinomas, both CCND1 amplification and cyclin D1, FADD, and cortactin protein expression were correlated with occult nodal metastases. CCND1 amplification and cyclin D1 expression correlated with occult nodal metastases. Cyclin D1 expression was validated in an independent multicenter cohort, confirming the correlation with occult nodal metastases in early FOM cancers. Cyclin D1 is a predictive biomarker for occult nodal metastases in early FOM cancers. Prospective research on biopsy material should confirm these results before implementing its use in routine clinical practice. © 2016 Wiley Periodicals, Inc. Head Neck 39: 326-333, 2017. © 2016 Wiley Periodicals, Inc.

The value of MR imaging of PDFASAT sequence in the diagnosis of extremities occult fractures

International Nuclear Information System (INIS)

Lu Lingquan; Xu Mingshen; Wu Qianzhi; Mao Chunnan; Wang Shuzi; Zhou Xingfan; Wang Liping

2004-01-01

Objective: To investigate the value of MR imaging of proton density weighted-fat saturated (PDFASAT) sequence in detecting the occult fracture of extremities. Methods: Thirty-one patients with acute trauma were studied using radiography and MR imaging within 45 days. MR sequences included FSE T 1 WI, T 2 WI, and PDFASAT. 21 occult fractures occurred in the knee joint, 6 in the hip joint, 1 in the elbow joint, 2 in the shoulder, and 1 in the ankle. Results: All 31 cases had normal radiographic results. 10 cases with proximal fibula, 4 with proximal tibia and 7 with femur condyle occult fractures were found in 21 knee joint acute trauma cases. 2 cases with intertrochanteric, 2 with femoral neck and 2 with cotyle occult fractures were found in 6 hip joint trauma cases. 2 proximal humerus occult fractures were found in 2 shoulder cases. 1 distal humerus and 1 distal fibula occult fracture was found in elbow and ankle cases. MR imaging demonstrated irregular linear low signal in the subcortical region on both T 1 WI and T 2 WI, and high signal changes around low signal were seen on T 2 WI in some cases. The high signal in PDFASAT sequence was more remarkable and wider than that on both T 1 WI and T 2 WI. Conclusion: MR imaging could determine the diagnosis of acute and chronic occult fractures. MRI should be the next choice when plain films fail to reveal suspected fractures in setting of suggestive symptoms and positive physical examination. PDFASAT would be the best effective sequence among the T 1 WI, T 2 WI, and PDFASAT. (author)

Occult Pelvic Lymph Node Involvement in Bladder Cancer: Implications for Definitive Radiation

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, Benjamin; Baumann, Brian C.; He, Jiwei; Tucker, Kai; Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Vaughn, David; Keefe, Stephen M. [Department of Medical Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Guzzo, Thomas; Malkowicz, S. Bruce [Department of Urology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Christodouleas, John P., E-mail: christojo@uphs.upenn.edu [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States)

2014-03-01

Purpose: To inform radiation treatment planning for clinically staged, node-negative bladder cancer patients by identifying clinical factors associated with the presence and location of occult pathologic pelvic lymph nodes. Methods and Materials: The records of patients with clinically staged T1-T4N0 urothelial carcinoma of the bladder undergoing radical cystectomy and pelvic lymphadenectomy at a single institution were reviewed. Logistic regression was used to evaluate associations between preoperative clinical variables and occult pathologic pelvic or common iliac lymph nodes. Percentages of patient with involved lymph node regions entirely encompassed within whole bladder (perivesicular nodal region), small pelvic (perivesicular, obturator, internal iliac, and external iliac nodal regions), and extended pelvic clinical target volume (CTV) (small pelvic CTV plus common iliac regions) were calculated. Results: Among 315 eligible patients, 81 (26%) were found to have involved pelvic lymph nodes at the time of surgery, with 38 (12%) having involved common iliac lymph nodes. Risk of occult pathologically involved lymph nodes did not vary with clinical T stage. On multivariate analysis, the presence of lymphovascular invasion (LVI) on preoperative biopsy was significantly associated with occult pelvic nodal involvement (odds ratio 3.740, 95% confidence interval 1.865-7.499, P<.001) and marginally associated with occult common iliac nodal involvement (odds ratio 2.307, 95% confidence interval 0.978-5.441, P=.056). The percentages of patients with involved lymph node regions entirely encompassed by whole bladder, small pelvic, and extended pelvic CTVs varied with clinical risk factors, ranging from 85.4%, 95.1%, and 100% in non-muscle-invasive patients to 44.7%, 71.1%, and 94.8% in patients with muscle-invasive disease and biopsy LVI. Conclusions: Occult pelvic lymph node rates are substantial for all clinical subgroups, especially patients with LVI on biopsy. Extended

Occult Hepatitis B Virus Among the Patients With Abnormal Alanine Transaminase

Science.gov (United States)

Makvandi, Manoochehr; Neisi, Niloofar; Khalafkhany, Davod; Makvandi, Kamyar; Hajiani, Eskandar; Shayesteh, Ali Akbar; Masjedi Zadeh, Abdolrahim; Sina, Amir Hosein; Hamidifard, Mojtaba; Rasti, Mojtaba; Aryan, Ehsan; Ahmadi, Kambiz; Yad Yad, Mohammad Jafar

2014-01-01

Background: The occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the sera or in the liver biopsy and the absence of hepatitis B surface antigen (HBsAg) by serological test. Objectives: The current study aimed to evaluate the occult HBV infection by polymerase chain reaction (PCR) and determine HBV genotyping among the patients with abnormal alanine transaminase (ALT) in Ahvaz city, Iran. Patients and Methods: The sera of 120 patients, 54 (45%) females and 66 (55%) males, with abnormal ALT 40-152 IU were collected. All the patients were negative for HBsAg for more than one year. The patients` sera were tested by PCR using primers specified for the S region of HBV. Then the positive PCR products were sequenced to determine HBV genotyping and phylogenic tree. Results: Of these 120 subjects, 12 (10%) patients including 6 (5%) males and 6 (5%) females were found positive for HBV DNA by PCR, which indicated the presence of occult HBV infection among these patients. The sequencing results revealed that genotype D was predominant with sub-genotyping D1 among OBI patients. Conclusions: Occult hepatitis B infection is remarkably prevalent in Ahvaz, Iran, and should be considered as a potential risk factor for the transmission of Hepatitis B Virus throughout the community by the carriers. PMID:25485052

Outcome of Concurrent Occult Hemothorax and Pneumothorax in Trauma Patients Who Required Assisted Ventilation

Directory of Open Access Journals (Sweden)

Ismail Mahmood

2015-01-01

Full Text Available Background. The management and outcomes of occult hemopneumothorax in blunt trauma patients who required mechanical ventilation are not well studied. We aimed to study patients with occult hemopneumothorax on mechanical ventilation who could be carefully managed without tube thoracostomy. Methods. Chest trauma patients with occult hemopneumothorax who were on mechanical ventilation were prospectively evaluated. The presence of hemopneumothorax was confirmed by CT scanning. Hospital length of stay, complications, and outcome were recorded. Results. A total of 56 chest trauma patients with occult hemopneumothorax who were on ventilatory support were included with a mean age of 36 ± 13 years. Hemopneumothorax was managed conservatively in 72% cases and 28% underwent tube thoracostomy as indicated. 29% of patients developed pneumonia, 16% had Acute Respiratory Distress Syndrome (ARDS, and 7% died. Thickness of hemothorax, duration of mechanical ventilation, and development of ARDS were significantly associated with tube thoracostomy in comparison to no-chest tube group. Conclusions. The majority of occult hemopneumothorax can be carefully managed without tube thoracostomy in patients who required positive pressure ventilation. Tube thoracotomy could be restricted to those who had evidence of increase in the size of the hemothorax or pneumothorax on follow-up chest radiographs or developed respiratory compromise.

Histopathological Parameters predicting Occult Nodal Metastases in Tongue Carcinoma Cases: An Indian Perspective.

Science.gov (United States)

Jacob, Tina Elizabeth; Malathi, N; Rajan, Sharada T; Augustine, Dominic; Manish, N; Patil, Shankargouda

2016-01-01

It is a well-established fact that in squamous cell carcinoma cases, the presence of lymph node metastases decreased the 5-year survival rate by 50% and also caused the recurrence of the primary tumor with development of distant metastases. Till date, the predictive factors for occult cervical lymph nodes metastases in cases of tongue squamous cell carcinoma remain inconclusive. Therefore, it is imperative to identify patients who are at the greatest risk for occult cervical metastases. This study was thus performed with the aim to identify various histopathologic parameters of the primary tumor that predict occult nodal metastases. The clinicopathologic features of 56 cases of lateral tongue squamous cell carcinoma with cT1NoMo/cT2NoMo as the stage and without prior radiotherapy or chemotherapy were considered. The surgical excision of primary tumor was followed by elective neck dissection. The glossectomy specimen along with the neck nodes were fixed in formalin and 5 urn thick sections were obtained. The hematoxylin & eosin stained sections were then subjected to microscopic examination. The primary tumor characteristics that were analyzed include tumor grade, invading front, depth of tumor, lymphovascular invasion, perineural invasion and inflammatory response. The nodes were examined for possible metastases using hematoxylin & eosin followed by cytokeratin immunohistochemistry. A total of 12 cases were found with positive occult nodal metastases. On performing univariate analysis, the histopathologic parameters that were found to be statistically significant were lymphovascular invasion (p = 0.004) and perineural invasion (p = 0.003) along with a cut-off depth of infiltration more than 5 mm (p = 0.01). Histopathologic assessment of the primary tumor specimen therefore continues to provide information that is central to guide clinical management, particularly in cases of occult nodal metastases. Clinical significance The study highlights the importance of

Treatment for occult hepatocellular carcinoma: does it offer survival advantages over symptom-driven treatment?

Science.gov (United States)

Kim, Kwang Min; Kim, Jiyu; Sinn, Dong Hyun; Kim, Hye Seung; Kim, Kyunga; Kang, Wonseok; Gwak, Geum-Youn; Paik, Yong-Han; Choi, Moon Seok; Lee, Joon Hyeok; Koh, Kwang Cheol; Paik, Seung Woon

2018-04-03

In order to claim a benefit of screen-based diagnosis for asymptomatic individuals, treatment of occult disease needs to offer survival advantages compared to the treatment of symptomatic disease, yet information on this issue is scarce with regard to hepatocellular carcinoma (HCC) screening. A total of 3353 treatment-naïve, consecutive, newly diagnosed HCC patients [age: 57.9 ± 10.3, male: 2,689 (80.2%), hepatitis B virus: 2555 (76.2%)], diagnosed between 2010 and 2013 were analyzed. Data on the mode of detection was prospectively collected at the time of HCC diagnosis and was used to group patients into occult or symptomatic cases. Overall, 643 (19.2%) patients were symptomatic cases. The proportion of patients undergoing resection, radiofrequency ablation or transplantation were lower in symptomatic cases than occult cases (20.8 vs. 56.2%, p offered a survival benefit to patients over symptomatic cases. These data support screening practices for asymptomatic individuals to diagnose occult HCC.

Predictive factors of occult neck metastasis in patients with oral squamous cell carcinoma

Directory of Open Access Journals (Sweden)

Renato Fortes Bittar

Full Text Available ABSTRACT INTRODUCTION: It is well established that cervical lymph node metastasis is the most important prognostic factor in patients with oral squamous cell carcinoma of the upper aerodigestive tract. The definition of parameters and classifications that could separate patients in groups of low, intermediate and high-risk is being attempted for several years. OBJECTIVE: The objective of this study was to determine possible predictive factors related to the occurrence of occult cervical lymph node metastasis through the analysis of histopathological reports of surgical specimens obtained after oral squamous cell carcinoma resection and selective neck dissections of patients initially classified as N0. METHODS: This was a primary, retrospective, observational, case-control study. Histopathological reports were reviewed to determine if some findings were related to the occurrence of occult lymph node metastasis. The events analyzed were oral cavity subsites, pT-stage, muscular infiltration, desmoplasia, vascular emboli, perineural infiltration, tumor thickness and compromised margins. RESULTS: Occult cervical metastasis accounted for 19.10 percent of the cases. Desmoplasia, perineural infiltration, tumor thickness and pT4a stage are predictive factors of occult neck metastasis (p-value = 0.0488, 0.0326, 0.0395, 0.0488, respectively. CONCLUSION: The accurate definition of predictive factors of occult cervical metastasis may guide the selection of patients that should be referred to radiotherapy, avoiding the unnecessary exposure of low-risk patients to radiation and allowing a better regional control of the disease in those of moderate or high risk.

Cassini UVIS solar occultations by Saturn's F ring and the detection of collision-produced micron-sized dust

Science.gov (United States)

Becker, Tracy M.; Colwell, Joshua E.; Esposito, Larry W.; Attree, Nicholas O.; Murray, Carl D.

2018-05-01

We present an analysis of eleven solar occultations by Saturn's F ring observed by the Ultraviolet Imaging Spectrograph (UVIS) on the Cassini spacecraft. In four of the solar occultations we detect an unambiguous signal from diffracted sunlight that adds to the direct solar signal just before or after the occultations occur. The strongest detection was a 10% increase over the direct signal that was enabled by the accidental misalignment of the instrument's pointing. We compare the UVIS data with images of the F ring obtained by the Cassini Imaging Science Subsystem (ISS) and find that in each instance of an unambiguous diffraction signature in the UVIS data, the ISS data shows that there was a recent disturbance in that region of the F ring. Similarly, the ISS images show a quiescent region of the F ring for all solar occultations in which no diffraction signature was detected. We therefore conclude that collisions in the F ring produce a population of small ring particles that can produce a detectable diffraction signal immediately interior or exterior to the F ring. The clearest example of this connection comes from the strong detection of diffracted light in the 2007 solar occultation, when the portion of the F ring that occulted the Sun had suffered a large collisional event, likely with S/2004 S 6, several months prior. This collision was observed in a series of ISS images (Murray et al., 2008). Our spectral analysis of the data shows no significant spectral features in the F ring, indicating that the particles must be at least 0.2 μm in radius. We apply a forward model of the solar occultations, accounting for the effects of diffracted light and the attenuated direct solar signal, to model the observed solar occultation light curves. These models constrain the optical depth, radial width, and particle size distribution of the F ring. We find that when the diffraction signature is present, we can best reproduce the occultation data using a particle population

Atmospheric stability index using radio occultation refractivity profiles

Indian Academy of Sciences (India)

A new stability index based on atmospheric refractivity at ∼500 hPa level and surface measurements of temperature ... able at different heights rather than pressure levels. However ..... the radio occultation technique being a limb sound-.

Prediction of occult hepatitis B virus infection in liver transplant donors through hepatitis B virus blood markers.

Science.gov (United States)

Tandoi, Francesco; Caviglia, Gian Paolo; Pittaluga, Fabrizia; Abate, Maria Lorena; Smedile, Antonina; Romagnoli, Renato; Salizzoni, Mauro

2014-11-01

Occult hepatitis B virus infection is defined as detectable HBV-DNA in liver of HBsAg-negative individuals, with or without detectable serum HBV-DNA. In deceased liver donors, results of tissue analysis cannot be obtained prior to allocation for liver transplantation. we investigated prevalence and predictability of occult hepatitis B using blood markers of viral exposure/infection in deceased liver donors. In 50 consecutive HBsAg-negative/anti-HBc-positive and 20 age-matched HBsAg-negative/anti-HBc-negative donors, a nested-PCR assay was employed in liver biopsies for diagnosis of occult hepatitis B according to Taormina criteria. All donors were characterized for plasma HBV-DNA and serum anti-HBs/anti-HBe. In liver tissue, occult hepatitis B was present in 30/50 anti-HBc-positive (60%) and in 0/20 anti-HBc-negative donors (pdonors with detectable HBV-DNA in plasma (n=5) or anti-HBs>1,000 mIU/mL (n=5) eventually showed occult infection, i.e, 10/30 occult hepatitis B-positive donors which could have been identified prior to transplantation. In the remaining 40 anti-HBc-positive donors, probability of occult infection was 62% for anti-HBe-positive and/or anti-HBs ≥ 58 mIU/mL; 29% for anti-HBe-negative and anti-HBsdonors, combining anti-HBc with other blood markers of hepatitis B exposure/infection allows to predict occult hepatitis B with certainty and speed in one third of cases. These findings might help refine the allocation of livers from anti-HBc-positive donors. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

[Prevalence of occult hepatitis B virus infection and its phylogenetic features among mother-teenager pairs].

Science.gov (United States)

Dong, Xiao-lian; Yao, Qing-qing; Wang, Xue-cai; Xu, Hai-tao; Wang, Xiao-li; Chen, Sheng-yu; Tang, Zhi-feng; Zheng, Ying-Jie

2013-03-01

Prevalence of occult hepatitis B virus (HBV) infection (OBI) was investigated in a paired mother-teenager population and HBV S gene variation including overt and occult HBV, was determined. A follow-up study based on an initial survey of 135 mother-teenager pairs was carried out through collection of questionnaires and blood samples HBsAg were detected by ELISA method, viral load by PCR amplification and HBV S gene by phylogenetic analysis. 102 pairs of subjects were followed-up. Blood samples from 94 mothers and 101 children were collected. OBI prevalence in mothers was 10.0% (6/60), significantly higher than 2.0% (2/101) in teenagers. Medians of viral load were 399.9 IU/ml and 247.6 IU/ml in overt and occult HBV strains, but without significant difference. 1 occult HBV strain belonged to genotype B with serotype adw while the other 7 were genotype C with serotype adr. 15 of the overt HBV strains belonged to genotype B with serotype adw and the other 8 were genotype C with serotype adr. Proportions of genotype-C strains were significantly higher in occult HBV strains than in overt HBV strains. OBI was seen in teenage-mother population.

Current management of occult bacteremia in infants

Directory of Open Access Journals (Sweden)

Eduardo Mekitarian Filho

2015-11-01

Full Text Available Objectives: To summarize the main clinical entities associated with fever without source (FWS in infants, as well as the clinical management of children with occult bacteremia, emphasizing laboratory tests and empirical antibiotics. Sources: A non-systematic review was conducted in the following databases – PubMed, EMBASE, and SciELO, between 2006 and 2015. Summary of the findings: The prevalence of occult bacteremia has been decreasing dramatically in the past few years, due to conjugated vaccination against Streptococcus pneumoniae and Neisseria meningitidis. Additionally, fewer requests for complete blood count and blood cultures have been made for children older than 3 months presenting with FWS. Urinary tract infection is the most prevalent bacterial infection in children with FWS. Some known algorithms, such as Boston and Rochester, can guide the initial risk stratification for occult bacteremia in febrile infants younger than 3 months. Conclusions: There is no single algorithm to estimate the risk of occult bacteremia in febrile infants, but pediatricians should strongly consider outpatient management in fully vaccinated infants older than 3 months with FWS and good general status. Updated data about the incidence of occult bacteremia in this environment after conjugated vaccination are needed. Resumo: Objetivos: Listar as principais entidades clínicas associadas a quadros de febre sem sinais localizatórios (FSSL em lactentes, bem como o manejo dos casos de bacteremia oculta com ênfase na avaliação laboratorial e na antibioticoterapia empírica. Fonte dos dados: Foi realizada revisão não sistemática da literatura nas bases de dados PubMed, EMBASE e Scielo no período de 2006 a 2015. Síntese dos dados: A ocorrência de bacteremia oculta vem diminuindo sensivelmente em lactentes com FSSL, principalmente devido à introdução da vacinação conjugada contra Streptococcus pneumoniae e Neisseria meningitidis nos últimos anos

[Results of conservative treatment in patients with occult pneumothorax].

Science.gov (United States)

Llaquet Bayo, Heura; Montmany Vioque, Sandra; Rebasa, Pere; Navarro Soto, Salvador

2016-04-01

An occult pneumothorax is found in 2-15% trauma patients. Observation (without tube thoracostomy) in these patients presents still some controversies in the clinical practice. The objective of the study is to evaluate the efficacy and the adverse effects when observation is performed. A retrospective observational study was undertaken in our center (university hospital level II). Data was obtained from a database with prospective registration. A total of 1087 trauma patients admitted in the intensive care unit from 2006 to 2013 were included. In this period, 126 patients with occult pneumothorax were identified, 73 patients (58%) underwent immediate tube thoracostomy and 53 patients (42%) were observed. Nine patients (12%) failed observation and required tube thoracostomy for pneumothorax progression or hemothorax. No patient developed a tension pneumothorax or experienced another adverse event related to the absence of tube thoracostomy. Of the observed patients 16 were under positive pressure ventilation, in this group 3 patients (19%) failed observation. There were no differences in mortality, hospital length of stay or intensive care length of stay between the observed and non-observed group. Observation is a safe treatment in occult pneumothorax, even in pressure positive ventilated patients. Copyright © 2014 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Occult injuries of the femoral neck in osteoporosis of aged patients

International Nuclear Information System (INIS)

Reichelt, H.G.

1985-01-01

Fractures of the femoral neck in elderly patients are often a complication in osteoporosis. Diagnosis of fractures with displacement and compression of fragments is quite easy. The negative radiograph in old patients complaining of hip pain is generally considered a characteristic feature of presensile osteoporotic pain. Clinical examples present patients with hip pain caused by occult injuries of the femoral neck. They should be regarded as imminent fractures and adequately treated. Bone scan is very helpful in the early detection of such occult osteroporotic injuries. (orig.) [de

Trio of Stellar Occultations by Pluto One Year Prior to New Horizons’ Arrival

Science.gov (United States)

2016-04-02

stellar signal, both with 20 s exposures with our frame-transfer Portable Occultation, Eclipse, and Transit System. Since Pluto had a geocentric velocity...and for New Horizons’s 2015 approach . For the July 31 event, though for our atmospheric studies we are glad to have detected the occultation of this

A 2017 stellar occultation by Orcus/Vanth

Science.gov (United States)

Sickafoose, Amanda A.; Bosh, Amanda S.; Levine, Stephen; Zuluaga, Carlos A.; Genade, Anja; Schindler, Karsten; Lister, Tim; Person, Michael J.

2017-10-01

(90482) Orcus is a large trans-Neptunian object (TNO) of diameter ~900 km, located in the 3:2 orbital resonance with Neptune. This plutino has a satellite, Vanth, approximately 280 km in diameter. Vanth orbits roughly 9000 km from Orcus in a ~9.5-day period. This system is particularly interesting, as Orcus falls between the small, spectrally-bland TNOs and the large TNOs having spectra rich in volatile features, while Vanth might have resulted from either collision or capture.A stellar occultation by Orcus was predicted to occur on 07 March 2017. Observations were made from five sites: the 0.6-m Astronomical Telescope of the University of Stuttgart (ATUS) at Sierra Remote Observatories (SRO), California; Las Cumbres Observatory’s 1-m telescope (ELP) at McDonald Observatory, Fort Davis, Texas; NASA’s 3-m InfraRed Telescope Facility (IRTF) on Mauna Kea, Hawaii; the 4.1-m Southern Astrophysical Research telescope (SOAR) on Cerro Pachón, Chile; and the 0.6-m Southeastern Association for Research in Astronomy telescope (SARA-CT) at Cerro Tololo, Chile. High-speed, visible-wavelength images were taken at all sites, in addition to simultaneous K-band images at the IRTF. A solid-body occultation was observed at both ELP and the IRTF. Offset midtimes and incompatible light ratios suggest that two different stars were occulted by two different bodies, likely Orcus and Vanth. See Bosh et al. this conference for details of the astrometry for the event. Here, we present results from the observations, including light curves, size and albedo estimates, and upper limits on a possible atmosphere.

Multiple surface antigen mutations in five blood donors with occult hepatitis B virus infection

NARCIS (Netherlands)

Zaaijer, H. L.; Torres, P.; Ontañón, A.; Ponte, L. González; Koppelman, M. H. G. M.; Lelie, P. N.; Hemert, F. J. van; Boot, H. J.

2008-01-01

Occult hepatitis B virus (HBV) infection is characterized by the presence of HBV DNA while the HBV surface antigen (HBsAg) remains undetectable. The HBV genomes in five asymptomatic blood donors with occult HBV infection and low viremia ( <10 to 1,000 HBV DNA copies/mL, genotype D) were studied. An

Photoreceptor atrophy in acute zonal occult outer retinopathy

DEFF Research Database (Denmark)

Zibrandtsen, N.; Munch, I.C.; Klemp, K.

2006-01-01

Purpose: To assess retinal morphology in acute zonal occult outer retinopathy (AZOOR). Methods: Three patients with a normal ophthalmoscopic fundus appearance, a history of photopsia, and visual field loss compatible with AZOOR were examined using optical coherence tomography, automated perimetry...

Magnetic field orientations in Saturn's upper ionosphere inferred from Voyager radio occultations

Science.gov (United States)

Hinson, D. P.

1984-01-01

The radio scintillations observed during occultations of Voyagers 1 and 2 by Saturn are analyzed to determine the morphology of plasma irregularities and hence the magnetic field orientation in Saturn's upper atmosphere. The measurement techniques, the weak scattering theory, and the method used to relate the observed radio scintillations to physical properties of the ionospheric irregularities are briefly described. Results on the spatial characteristics of the irregularities are presented, and the magnetic field orientation in Saturn's ionosphere is inferred. Although the occultation measurements generally confirm the accuracy of the Saturnian magnetic field model of Connerney et al. (1982), it is found that a small adjustment of the coefficients in that model's zonal harmonic expansion would remove the discrepancy between the model predictions and the measurements. A strategy for obtaining improved measurements of Saturn's magnetic field from radio occultation observations of scintillations and Faraday rotation using an orbiting spacecraft is briefly discussed.

Theoretical performance of serrated external occulters for solar coronagraphy. Application to ASPIICS

Science.gov (United States)

Rougeot, R.; Aime, C.

2018-04-01

Context. This study is made in the context of the future solar coronagraph ASPIICS of the ESA formation-flying mission Proba-3. Aims: In the context of solar coronagraphy, we provide a comparative study of the theoretical performance of serrated (or toothed) external occulters by varying the number and size of the teeth, which we compare to the sharp-edged and apodized disks. The tooth height is small (a few centimeters), to avoid hindering the observation of the solar corona near the limb. We first analyze the diffraction pattern produced by such occulters. In a second step, we compute the umbra profile by integration over the Sun. Methods: We explored a few methods to compute the diffraction pattern. Two of them were implemented. The first is based on 2D fast Fourier transformation (FFT) routines and a multiplication by the Fresnel filter of the form exp(-iπλzu2). Simple rules were derived and discussed to set the sampling conditions. The Maggi-Rubinowicz representation is then proposed as an alternative method, and is proven to be very efficient for this study. Results: Serrated occulters tend to create a two-level intensity pattern, the inner being the darker, which perfectly matches a previously reported geometrical prediction. The diffraction in this central region is lower by two to four orders of magnitude when compared to the sharp-edged disk. The achieved umbra level at the center ranges from 10-4 to below 10-7, depending on the geometry of the teeth. Conclusions: Our study shows that serrated occulters can achieve a high rejection and can almost reach the performance of the apodized disk when very many teeth are used. We prove that shaped occulters must be preferred to simple disks in solar and stellar coronagraphy.

US production of natural gas from tight reservoirs

International Nuclear Information System (INIS)

1993-01-01

For the purposes of this report, tight gas reservoirs are defined as those that meet the Federal Energy Regulatory Commission's (FERC) definition of tight. They are generally characterized by an average reservoir rock permeability to gas of 0.1 millidarcy or less and, absent artificial stimulation of production, by production rates that do not exceed 5 barrels of oil per day and certain specified daily volumes of gas which increase with the depth of the reservoir. All of the statistics presented in this report pertain to wells that have been classified, from 1978 through 1991, as tight according to the FERC; i.e., they are ''legally tight'' reservoirs. Additional production from ''geologically tight'' reservoirs that have not been classified tight according to the FERC rules has been excluded. This category includes all producing wells drilled into legally designated tight gas reservoirs prior to 1978 and all producing wells drilled into physically tight gas reservoirs that have not been designated legally tight. Therefore, all gas production referenced herein is eligible for the Section 29 tax credit. Although the qualification period for the credit expired at the end of 1992, wells that were spudded (began to be drilled) between 1978 and May 1988, and from November 5, 1990, through year end 1992, are eligible for the tax credit for a subsequent period of 10 years. This report updates the EIA's tight gas production information through 1991 and considers further the history and effect on tight gas production of the Federal Government's regulatory and tax policy actions. It also provides some high points of the geologic background needed to understand the nature and location of low-permeability reservoirs

TITAN’S UPPER ATMOSPHERE FROM CASSINI/UVIS SOLAR OCCULTATIONS

Energy Technology Data Exchange (ETDEWEB)

Capalbo, Fernando J.; Bénilan, Yves [Laboratoire Inter-Universitaire des Systèmes Atmosphériques (LISA), UMR 7583 du CNRS, Universités Paris Est Créteil (UPEC) and Paris Diderot - UPD, 61 avenue du Général de Gaulle, F-94010, Créteil Cédex (France); Yelle, Roger V.; Koskinen, Tommi T., E-mail: fernando.capalbo@lisa.u-pec.fr [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721 (United States)

2015-12-01

Titan’s atmosphere is composed mainly of molecular nitrogen, methane being the principal trace gas. From the analysis of 8 solar occultations measured by the Extreme Ultraviolet channel of the Ultraviolet Imaging Spectrograph (UVIS) on board Cassini, we derived vertical profiles of N{sub 2} in the range 1100–1600 km and vertical profiles of CH{sub 4} in the range 850–1300 km. The correction of instrument effects and observational effects applied to the data are described. We present CH{sub 4} mole fractions, and average temperatures for the upper atmosphere obtained from the N{sub 2} profiles. The occultations correspond to different times and locations, and an analysis of variability of density and temperature is presented. The temperatures were analyzed as a function of geographical and temporal variables, without finding a clear correlation with any of them, although a trend of decreasing temperature toward the north pole was observed. The globally averaged temperature obtained is (150 ± 1) K. We compared our results from solar occultations with those derived from other UVIS observations, as well as studies performed with other instruments. The observational data we present confirm the atmospheric variability previously observed, add new information to the global picture of Titan’s upper atmosphere composition, variability, and dynamics, and provide new constraints to photochemical models.

UARS Halogen Occultation Experiment (HALOE) Level 2 V001

Data.gov (United States)

National Aeronautics and Space Administration — The HALOE home page on the WWW is http://haloe.gats-inc.com/home/index.php The Halogen Occultation Experiment (HALOE) on NASA's Upper Atmosphere Research Satellite...

Detection of an occult transclival cerebrospinal fluid fistula by CT and MRI

International Nuclear Information System (INIS)

Schick, B.; Brors, D.; Draf, W.; Goedecke, A.; Prescher, A.

1998-01-01

We describe an unusual occult transclival cerebrospinal fluid (CSF) fistula to the sphenoid sinus demonstrated by MRI. CT was performed because of a posterior cerebral infarct caused by cardiac arrhythmia. Axial sections showed fluid in the sphenoid sinus. High-resolution scans revealed a bony defect 3 mm in diameter of the posterior wall of the sphenoid sinus, and MRI showed a transclival CSF fistula. This occult lesion was confirmed by surgery and duraplasty was successfully performed via an endonasal approach. (orig.)

Hermetic compartments leak-tightness enhancement

International Nuclear Information System (INIS)

Murani, J.

2000-01-01

In connection with the enhancement of the nuclear safety of the Jaslovske Bohunice V-1 NPP actions for the increase of the leak tightness are performed. The reconstruction has been done in the following directions: hermetic compartments leak tightness enhancement; air lock installation; installation of air lock in SP 4 vent system; integrated leakage rate test to hermetic compartments with leak detection. After 'major' leaks on the hermetic boundary components had been eliminated, since 1994 works on a higher qualitative level began. The essence of the works consists in the detection and identification of leaks in the structural component of the hermetic boundary during the planned refueling outages. The results of the Small Reconstruction and gradual enhancement of leak tightness are presented

Lunar occultation observations of the Crab Nebula

International Nuclear Information System (INIS)

Maloney, F.P.

1977-01-01

Three lunar of occultations of the Crab Nebula were observed, two at 114 MHz and one at 26.3 MHz, during the 1974 series of events. The higher frequency observations were deconvolved of diffraction effects to yield four strip integrated brightness profiles of the Nebula, with an effective resolution of 30 arc-seconds. These four profiles were Fourier inverted and cleaned of sidelobe structure to synthesize a two-dimensional map of the Nebula. At 114 MHz, the Nebula is composed of a broad envelope of emission which contains several smaller sources. The attenuation of the low radio frequency radiation by the thermal hydrogen in the filaments is considered as a possible mechanism to explain these new data. The 26.3 MHz observations indicate the presence of a bright, localized source containing greater than 80% of the flux of the Nebula. The position of the source is confined by the data to a narrow strip centered at the pulsar position. Both sets of data are compared with past occultation observations

High prevalence of occult left heart disease in scleroderma-pulmonary hypertension.

Science.gov (United States)

Fox, Benjamin D; Shimony, Avi; Langleben, David; Hirsch, Andrew; Rudski, Lawrence; Schlesinger, Robert; Eisenberg, Mark J; Joyal, Dominique; Hudson, Marie; Boutet, Kim; Serban, Alexandrina; Masetto, Ariel; Baron, Murray

2013-10-01

Our study aimed to determine the prevalence of occult left-heart disease in patients with scleroderma and pulmonary hypertension. In patients with pulmonary hypertension (mean pulmonary artery pressure (mean PAP)≥25 mmHg), differentiation between pre- and post-capillary pulmonary hypertension has been made according to pulmonary artery wedge pressure (PAWP) less than or more than 15 mmHg, respectively. We performed a retrospective chart review of 107 scleroderma patients. All patients with suspected pulmonary hypertension had routine right or left heart catheterisation with left ventricular end-diastolic pressure (LVEDP) measurement pre-/post-fluid challenge. We extracted demographic, haemodynamic and echocardiographic data. Patients were classified into one of four groups: haemodynamically normal (mean PAP15 mmHg); occult PVH (mean PAP≥25 mmHg, PAWP≤15 mmHg, LVEDP>15 mmHg before or after fluid challenge); and pulmonary arterial hypertension (PAH) (mean PAP≥25 mmHg, PAWP≤15 mmHg and LVEDP≤15 mmHg before or after fluid challenge). 53 out of 107 patients had pulmonary hypertension. Based on the PAWP-based definition, 29 out of 53 had PAH and 24 out of 53 had PVH. After considering the resting and post-fluid-challenge LVEDP, 11 PAH patients were reclassified as occult PVH. The occult PVH group was haemodynamically, echocardiographically and demographically closer to the PVH group than the PAH group. PVH had high prevalence in our scleroderma-pulmonary hypertension population. Distinguishing PAH from PVH with only PAWP may result in some PVH patients being misclassified as having PAH.

An integration time adaptive control method for atmospheric composition detection of occultation

Science.gov (United States)

Ding, Lin; Hou, Shuai; Yu, Fei; Liu, Cheng; Li, Chao; Zhe, Lin

2018-01-01

When sun is used as the light source for atmospheric composition detection, it is necessary to image sun for accurate identification and stable tracking. In the course of 180 second of the occultation, the magnitude of sun light intensity through the atmosphere changes greatly. It is nearly 1100 times illumination change between the maximum atmospheric and the minimum atmospheric. And the process of light change is so severe that 2.9 times per second of light change can be reached. Therefore, it is difficult to control the integration time of sun image camera. In this paper, a novel adaptive integration time control method for occultation is presented. In this method, with the distribution of gray value in the image as the reference variable, and the concepts of speed integral PID control, the integration time adaptive control problem of high frequency imaging. The large dynamic range integration time automatic control in the occultation can be achieved.

Stellar Occultations by TNOs and Centaurs: first results in the “Gaia era”

Science.gov (United States)

Rossi, Gustavo; Vieira-Martins, Roberto; Sicardy, Bruno; Ortiz, Jose Luis; Rio Group, Lucky Star Occultation Team, Granada Occultation Team

2017-10-01

After the first release of the GAIA catalog (in September/2016), stellar positions are now known with unprecedented accuracy, reaching values of the order of milliarcseconds. This improvement reflected into a stunning accuracy on the astrometry of moving objects, such as TNOs. Unfortunately, Gaia stars proper motions will be only available on the second data release (DR2) next year, so there is still a need to use hybrid stellar catalogs for occultation predictions until then. Despite that, stellar occultations predictions are now much more accurate, and the biggest uncertainties comes mainly from the object ephemerides. This issue will be overcome by large surveys such as the LSST, which will provide positions for the known TNOs and it is expected to increase the number of known TNOs by nearly 40,000, with an unprecedent amount of acquired information.This huge amount of data also poses a new era in stellar occultations: predictions will be very accurate and the participation of professional astronomers, laboratories, and the amateur community will be crucial to observe the predicted events; observation campaigns will need to be selected according to a specific scientific purpose such as the probability to detect rings or archs around a body, the presence of atmosphere or even the detection of topographic features; the development of softwares capable of reducing the data more efficiently and an easier method to coordinate observation campaigns are needed.Here we present some impressive results obtained from predictions and observed occultations in 2017 (among them we have Pluto, Chariklo and Haumea), the problems we are starting to face in the beginning of the “Gaia era” and the future challenges of stellar occultation.

Helios-1 Faraday rotation experiment - Results and interpretations of the solar occultations in 1975

Science.gov (United States)

Volland, H.; Bird, M. K.; Levy, G. S.; Stelzried, C. T.; Seidel, B. L.

1977-01-01

The first of two solar occultations of the satellite Helios-1 in 1975 occurred in April when the satellite's ray path approached the west limb of the sun to a minimum distance of 1.63 solar radii. The second occultation took place in late August/early September when Helios-1 was totally eclipsed by the photosphere. Measurements of the polarization angle of the linearly polarized telemetry signal were performed with automatic tracking polarimeters at the 64 m Goldstone Tracking Station in California and also at the 100 m radio telescope in Effelsberg, West Germany. The coronal Faraday rotation as a function of the solar offset for both occultations is shown in graphs. The theoretical significance of the observations is investigated.

Disparities in the receipt of fecal occult blood test versus endoscopy among Filipino American immigrants.

Science.gov (United States)

Maxwell, Annette E; Danao, Leda L; Crespi, Catherine M; Antonio, Cynthia; Garcia, Gabriel M; Bastani, Roshan

2008-08-01

This report examines disparities associated with the type of colorectal screening test, fecal occult blood test versus endoscopy, within a particular racial/ethnic group, Filipino American immigrants. Between July 2005 and October 2006, Filipino Americans aged 50 to 75 years from 31 community organizations in Los Angeles completed a 15-minute survey in English (65%) or Filipino (35%). Of the 487 respondents included in this analysis, 257 (53%) had never received any type of colorectal cancer screening. Among the 230 subjects who had ever received a routine screening test, 78 had fecal occult blood test only (16% of the total sample), and 152 had endoscopy with or without fecal occult blood test (31% of the total sample). After controlling for access to care and key demographic variables in a multivariate analysis, only two characteristics distinguished between respondents who had fecal occult blood test only versus those who had endoscopy: acculturation, assessed by percent lifetime in the United States and language of interview, and income. Our data suggest a two-tier system, fecal occult blood test for less acculturated Filipino Americans with lower income versus endoscopy for Filipino immigrants with higher levels of acculturation and income. The disparity persists after adjusting for access to care. Instead of treating minority groups as monolithic, differences within groups need to be examined so that interventions can be appropriately targeted.

Detection of an occult transclival cerebrospinal fluid fistula by CT and MRI

Energy Technology Data Exchange (ETDEWEB)

Schick, B.; Brors, D.; Draf, W. [Department of Ear, Nose and Throat Diseases, Head, Neck and Facial Plastic Surgery, Marburg Univ. (Germany); Goedecke, A. [Department of Radiology, Academic Teaching Hospital, Fulda (Germany); Prescher, A. [Department of Anatomy and Embryology, University Medical School, RWTH, Aachen (Germany)

1998-12-01

We describe an unusual occult transclival cerebrospinal fluid (CSF) fistula to the sphenoid sinus demonstrated by MRI. CT was performed because of a posterior cerebral infarct caused by cardiac arrhythmia. Axial sections showed fluid in the sphenoid sinus. High-resolution scans revealed a bony defect 3 mm in diameter of the posterior wall of the sphenoid sinus, and MRI showed a transclival CSF fistula. This occult lesion was confirmed by surgery and duraplasty was successfully performed via an endonasal approach. (orig.) With 3 figs., 19 refs.

Diagnostic yield of lumbosacral magnetic resonance imaging requested by paediatric urology consultations.

Science.gov (United States)

Fernández-Ibieta, M; Rojas Ticona, J; Villamil, V; Guirao Piñera, M J; López García, A; Zambudio Carmona, G

2017-11-01

In the historical series, the diagnostic yield of lumbosacral magnetic resonance imaging to rule out occult spinal dysraphism (or occult myelodysplasia), requested by paediatric urology, ranged from 2% to 15%. The aim of this study was to define our cost-effectiveness in children with urinary symptoms and to define endpoints that increase the possibility of finding occult spinal dysraphism. A screening was conducted on patients with urinary dysfunction for whom an magnetic resonance imaging was requested by the paediatric urology clinic, for persistent symptoms after treatment, voiding dysfunction or other clinical or urodynamic findings. We analysed clinical (UTI, daytime leaks, enuresis, voiding dysfunction, urgency, renal ultrasonography, lumbosacral radiography, history of acute urine retention, skin stigma and myalgia) and urodynamic endpoints (hyperactivity or areflexia, voiding dysfunction, interrupted pattern, accommodation value and maximum flow). A univariate analysis was conducted with SPSS 20.0. We analysed 21 patients during the period 2011-2015. The median age was 6 years (3-10). Three patients (14.3%) had occult spinal dysraphism: one spinal lipoma, one filum lipomatosus and one caudal regression syndrome with channel stenosis. The endpoints with statistically significant differences were the myalgias and the history of acute urine retention (66.7% vs. 5.6%, P=.04; OR= 34; 95%CI: 1.5-781 for both endpoints). The diagnostic yield of magnetic resonance imaging requested for children with urinary dysfunctions without skin stigma or neuro-orthopaedic abnormalities is low, although nonnegligible. In this group, the patients with a history of acute urine retention and muscle pain (pain, «cramps») can experience a greater diagnostic yield or positive predictive value. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Occultism in an African context: a case for the Vhavenda-speaking people of the Limpopo Province

Directory of Open Access Journals (Sweden)

T. D. Mashau

2007-07-01

Full Text Available Occultism in Africa is as old as the primal religion itself, or what came to be known as African Traditional Religion (ATR in mo- dern times. It dates back to time immemorial. Occultism in Africa has taken various forms and has manifested in different ways over the ages, i.e. spiritism, divination, witchcraft and ma- gic. The underlying premise of African occultism is the belief in a spiritual world with spiritual forces that have power to inflict harm on the living. In the traditional African worldview suffering of every sort – illness, barrenness, drought and death – is nor- mally explained in personal terms: “there is always somebody”. This “somebody” often belongs to the world of the occult: a “spirit” has brought pain to human beings and must therefore be repelled or accommodated. This is very common among the Vhavenda-speaking people of the Limpopo Province. This ar- ticle seeks to investigate how occultism is practised among these people and to provide a reformed perspective as to how people who are suffering under demonic attacks can be helped. Contrary to other Christian traditions that see exorcism as the only way out, reformed theology suggests a missio-pastoral approach in dealing with the problem.

Incidence of occult leiomyosarcoma in presumed morcellation cases: a database study.

Science.gov (United States)

Rodriguez, Ana M; Asoglu, Mehmet R; Sak, Muhammet Erdal; Tan, Alai; Borahay, Mostafa A; Kilic, Gokhan S

2016-02-01

Our objective was to estimate the incidence of uterine leiomyosarcoma in patients with leiomyomas following laparoscopic supracervical hysterectomy and myomectomy procedures. For this study, we analyzed records of 13,964 women aged 25-64 years who underwent laparoscopic supracervical hysterectomies or myomectomies for leiomyomas from 2002 to 2011 using Clinformatics DataMart. Patient records were divided into two groups: history of laparoscopic supracervical hysterectomy and history of myomectomy. Subjects were tracked to identify diagnosis of leiomyosarcoma within 1 year of the procedure. We analyzed data from the 25-39, 40-49, and 50-64 age brackets. Evidence was obtained from a cohort study from national private insurance claims in the US. Our results showed the incidence of occult leiomyosarcoma developing within 1 year following supracervical hysterectomy using a laparoscopic-assisted approach are 9.8, 10.7, and 33.4 per 10,000 for the 25-39, 40-49, and 50-64 age brackets, respectively; the overall incidence rate is 13.1 per 10,000. The incidence rate of occult leiomyosarcoma developing within 1 year following myomectomy using a laparoscopic-assisted approach are 0.0, 33.8, and 90.1 per 10,000 for the 25-39, 40-49, and 50-64 age brackets, respectively; the overall incidence rate is 17.3 per 10,000. Our analysis shows the overall risk of being diagnosed with occult leiomyosarcoma is 12.9 per 10,000 in laparoscopic-assisted supracervical hysterectomy and myomectomy for patients younger than 49. There is no evidence of occult leiomyosarcoma 1 year after operation for patients younger than 40 who underwent laparoscopic myomectomy. Copyright © 2015. Published by Elsevier Ireland Ltd.

Lowest-order average effect of turbulence on atmospheric profiles derived from radio occultation

International Nuclear Information System (INIS)

Eshleman, V.R.; Haugstad, B.S.

1977-01-01

Turbulence in planetary atmospheres and ionospheres causes changes in angles of refraction of radio waves used in occultation experiments. Atmospheric temperature and pressure profiles, and ionospheric electron concentration profiles, derived from radio occultation measurements of Doppler frequency contain errors due to such angular offsets. The lowest-order average errors are derived from a geometrical-optics treatment of the radio-wave phase advance caused by the addition of uniform turbulence to an initially homogeneous medium. It is concluded that the average profile errors are small and that precise Doppler frequency measurements at two or more wavelengths could be used to help determine characteristics of the turbulence, as well as accuracy limits and possible correction terms for the profiles. However, a more detailed study of both frequency and intensity characteristics in radio and optical occultation measurements of turbulent planetary atmospheres and ionospheres is required to realize the full potential of such measurements

Occult hepatitis B virus coinfection in HIV-positive African migrants to the UK: a point prevalence study.

Science.gov (United States)

Chadwick, D; Doyle, T; Ellis, S; Price, D; Abbas, I; Valappil, M; Geretti, A M

2014-03-01

Occult (surface antigen-negative/DNA-positive) hepatitis B virus (HBV) infection is common in areas of the world where HBV is endemic. The main objectives of this study were to determine the prevalence of occult HBV infection in HIV-infected African migrants to the UK and to determine factors associated with occult coinfection. This anonymized point-prevalence study identified Africans attending three HIV clinics, focussing on patients naïve to antiretroviral therapy (ART). Stored blood samples were tested for HBV DNA. Prevalence was calculated in the entire cohort, as well as in subpopulations. Risk factors for occult HBV coinfection were identified using logistic regression analysis. Among 335 HIV-positive African migrants, the prevalence of occult HBV coinfection was 4.5% [95% confidence interval (CI) 2.8-7.4%] overall, and 6.5% (95% CI 3.9-10.6%) and 0.8% (95% CI 0.2-4.6%) in ART-naïve and ART-experienced patients, respectively. Among ART-naïve anti-HBV core (anti-HBc)-positive patients, the prevalence was 16.4% (95% CI 8.3-25.6%). The strongest predictor of occult coinfection was anti-HBc positivity [odds ratio (OR) 7.4; 95% CI 2.0-27.6]. Median HBV DNA and ALT levels were 54 IU/mL [interquartile range (IQR) 33-513 IU/mL] and 22 U/L (IQR 13-27 U/L), respectively. Occult HBV coinfection remains under-diagnosed in African HIV-infected patients in the UK. Given the range of HBV DNA levels observed, further studies are warranted to determine its clinical significance and to guide screening strategies and ART selection in these patients. © 2013 British HIV Association.

Astrometry of the Orcus/Vanth occultation on UT 7 March 2017

Science.gov (United States)

Bosh, Amanda S.; Zuluaga, Carlos; Levine, Stephen; Sickafoose, Amanda A.; Genade, Anja; Schindler, Karsten; Lister, Tim; Person, Michael J.

2017-10-01

On UT 7 March 2017, Orcus was predicted to occult a star with m=14.3. Observations were made at five observatories: the 0.6-m Astronomical Telescope of the University of Stuttgart (ATUS) at Sierra Remote Observatories (SRO), California; Las Cumbres Observatory’s 1-m telescope (ELP) at McDonald Observatory, Fort Davis, Texas; NASA’s 3-m InfraRed Telescope Facility (IRTF) on Mauna Kea, Hawaii; the 4.1-m Southern Astrophysical Research telescope (SOAR) on Cerro Pachón, Chile; and the 0.6-m Southeastern Association for Research in Astronomy telescope (SARA-CT) at Cerro Tololo, Chile. While observations at all sites were successful, only two—ELP and IRTF—observed solid-body occultation signatures. We will discuss the various predictions for this event and the reasons for the differences among them, including an offset of 130 mas for the star position from the position in the Gaia catalog. The sum of the positive and negative detections place constraints on the geometry of the Orcus/Vanth system, and we present our astrometric results for the geometric solution for this occultation. The implications of the light curve analyses are presented by Sickafoose et al., this conference.

Radio occultation bending angle anomalies during tropical cyclones

DEFF Research Database (Denmark)

Biondi, Riccardo; Neubert, Torsten; Syndergaard, S.

2011-01-01

-located radiosondes, climatology of tropopause altitudes and GOES analyses are also shown to support the hypothesis that the bending angle anomaly can be used as an indicator of convective towers. The results are discussed in connection to the GPS radio occultation receiver which will be part of the Atomic Clock...

Tight connection between fission gas discharge channels

International Nuclear Information System (INIS)

Jung, W.; Peehs, M.; Rau, P.; Krug, W.; Stechemesser, H.

1978-01-01

The invention is concerned with the tight connection between the fission gas discharge channel, leading away from the support plate of a gas-cooled reactor, and the top of the fuel element suspended from this support plate. The closure is designed to be gas-tight for the suspended as well as for the released fuel element. The tight connection has got an annular body resting on the core support plate in the mouth region of the fission gas discharge channel. This body is connected with the fission gas discharge channel in the fuel element top fitting via a gas-tight part and supported by a compression spring. Care is taken for sealing if the fuel element is removal. (RW) [de

Low-Cost Small Satellite Atmospheric Rotating Solar Occultation Imager (ROI)

Data.gov (United States)

National Aeronautics and Space Administration — Utilizing a unique, new occultation technique involving imaging, the ROI concept will meet or exceed the quality of SAGE measurements at a small fraction of the...

Tightly Secure Signatures From Lossy Identification Schemes

OpenAIRE

Abdalla , Michel; Fouque , Pierre-Alain; Lyubashevsky , Vadim; Tibouchi , Mehdi

2015-01-01

International audience; In this paper, we present three digital signature schemes with tight security reductions in the random oracle model. Our first signature scheme is a particularly efficient version of the short exponent discrete log-based scheme of Girault et al. (J Cryptol 19(4):463–487, 2006). Our scheme has a tight reduction to the decisional short discrete logarithm problem, while still maintaining the non-tight reduction to the computational version of the problem upon which the or...

Digital solar edge tracker for the Halogen Occultation Experiment

Science.gov (United States)

Mauldin, L. E., III; Moore, A. S.; Stump, C. W.; Mayo, L. S.

1987-01-01

The optical and electronic design of the Halogen Occultation Experiment (Haloe) elevation sun sensor is described. The Haloe instrument is a gas-correlation radiometer now being developed at NASA Langley for the Upper Atmosphere Research Satellite. The system uses a Galilean telescope to form a solar image on a linear silicon photodiode array. The array is a self-scanned monolithic CCD. The addresses of both solar edges imaged on the array are used by the control/pointing system to scan the Haloe science instantaneous field of view (IFOV) across the vertical solar diameter during instrument calibration and then to maintain the science IFOV 4 arcmin below the top edge during the science data occultation event. Vertical resolution of 16 arcsec and a radiometric dynamic range of 100 are achieved at the 700-nm operating wavelength. The design provides for loss of individual photodiode elements without loss of angular tracking capability.

Significance of occult hbv infection in patients with chronic hepatitis c

International Nuclear Information System (INIS)

Anwar, W.; Sarwar, M.; Saif, M.; Hussain, A.B.; Tariq, W.Z.

2006-01-01

Objective: To determine the frequency of occurrence of occult Hepatitis B infection in chronic hepatitis C patients and its impact (if any) on the effectivity of standard chronic hepatitis C treatment. Design: Quasi-experimental study. Place and Duration of Study: The study was conducted at the Department of Medicine, Military Hospital, Rawalpindi, and Virology Department, Armed Forces Institute of Pathology, Rawalpindi, for a period of nine months from January 2003 to September 2003. Patients and Methods: This study was conducted on 30 HBsAg negative patients with chronic hepatitis C liver disease who were receiving combination therapy with interferon and ribavirin. Occult hepatitis B infection was assessed by carrying out HBV DNA by polymerase chain reaction (PCR) in the sera of these patients. Markers of previous hepatitis B infection Le; anti-HBs and total anti-HBc antibodies were also tested. Response to treatment for hepatitis C (with interferon and ribavirin) was assessed at the end of six months of therapy by measuring ALT levels and HCV RNA by PCR in the serum. Results: In our study only one patient (3.33%) was found to be harbouring HBV DNA in the serum detectable by PCR, with markers of previous HBV infection (both anti HBc antibodies and anti HBs antibodies were positive). A total 14 patients (46.67%) had markers of previous HBV infection, while 16 patients (53.33%) had no such sero markers. Twenty five out of 30 patients (83.33%) responded to treatment and 5 (16.66%) turned out to be non-responders. The single case of occult hepatitis B detected in this study responded to hepatitis C treatment. Conclusion: Occult hepatitis B is not a common occurrence in chronic hepatitis C patients and it did not alter the outcome of treatment for hepatitis C in our study. (author)

Fecal Occult Blood Test (FOBT): MedlinePlus Lab Test Information

Science.gov (United States)

... caused by a variety of conditions, including: Polyps Hemorrhoids Diverticulosis Ulcers Colitis , a type of inflammatory bowel ... on a fecal occult blood test include ulcers, hemorrhoids, polyps, and benign tumors. If your test results ...

Tightness Entropic Uncertainty Relation in Quantum Markovian-Davies Environment

Science.gov (United States)

Zhang, Jun; Liu, Liang; Han, Yan

2018-05-01

In this paper, we investigate the tightness of entropic uncertainty relation in the absence (presence) of the quantum memory which the memory particle being weakly coupled to a decohering Davies-type Markovian environment. The results show that the tightness of the quantum uncertainty relation can be controlled by the energy relaxation time F, the dephasing time G and the rescaled temperature p, the perfect tightness can be arrived by dephasing and energy relaxation satisfying F = 2G and p = 1/2. In addition, the tightness of the memory-assisted entropic uncertainty relation and the entropic uncertainty relation can be influenced mainly by the purity. While in memory-assisted model, the purity and quantum correlation can also influence the tightness actively while the quantum entanglement can influence the tightness slightly.

Occult spontaneous lateral intrasphenoidal encephalocele: A rare presentation

Directory of Open Access Journals (Sweden)

Shahina Bano

2013-01-01

Full Text Available Basal encephaloceles are extremely rare congenital malformations. Advanced cross-sectional imaging modalities like computed tomography and magnetic resonance imaging are necessary for diagnosing the asymptomatic, occult basal encephalocele and planning the surgical approach. We present an interesting case of clinically silent right-sided lateral intrasphenoidal encephalocele through a large bony defect.

Results from occultations by minor planets

International Nuclear Information System (INIS)

Taylor, G.E.

1982-01-01

Since the minor planets are believed to consist of primordial matter dating from the time of the formation of the solar system there is great interest in determining their composition. It is therefore necessary to calculate their densities, for which we need accurate masses and sizes. On the rare occasions when a minor planet occults a star, timed observations of the event from a number of observing sites enable an accurate size of the minor planet to be determined. (Auth.)

Progress in turbulence detection via GNSS occultation data

Directory of Open Access Journals (Sweden)

L. B. Cornman

2012-04-01

Full Text Available The increased availability of radio occultation (RO data offers the ability to detect and study turbulence in the Earth's atmosphere. An analysis of how RO data can be used to determine the strength and location of turbulent regions is presented. This includes the derivation of a model for the power spectrum of the log-amplitude and phase fluctuations of the permittivity (or index of refraction field. The bulk of the paper is then concerned with the estimation of the model parameters. Parameter estimators are introduced and some of their statistical properties are studied. These estimators are then applied to simulated log-amplitude RO signals. This includes the analysis of global statistics derived from a large number of realizations, as well as case studies that illustrate various specific aspects of the problem. Improvements to the basic estimation methods are discussed, and their beneficial properties are illustrated. The estimation techniques are then applied to real occultation data. Only two cases are presented, but they illustrate some of the salient features inherent in real data.

Sizes of the Smallest Particles at Saturn Ring Edges from Diffraction in UVIS Stellar Occultations

Science.gov (United States)

Eckert, S.; Colwell, J. E.; Becker, T. M.; Esposito, L. W.

2017-12-01

Cassini's Ultraviolet Imaging Spectrograph (UVIS) has observed more than 150 ring stellar occultations since its arrival at Saturn in 2004. We use stellar occultation data from the UVIS High Speed Photometer (HSP) to identify diffraction signals at ring edges caused by small particles diffracting light into the detector and consequently increasing the signal above that of the unocculted star. The shape of a diffraction signal is indicative of the particle size distribution at the ring edge, which may be a dynamically perturbed region. Becker et al. (2015 Icarus doi:10.1016/j.icarus.2015.11.001) analyzed diffraction signals at the outer edge of the A Ring and the edges of the Encke Gap. We apply the Becker et al. (2015) model to the outer edge of the B Ring as well as the edges of ringlets within the C Ring and Cassini Division. In addition, we analyze diffraction signatures at the A Ring outer edge in 2 new occultations. The best-fit model signals to these occultations are consistent with the findings of Becker et al. (2015) who found an average minimum particle size amin =4.5 mm and average power law slope q=3.2. At the B Ring outer edge, we detect a diffraction signal in 10 of 28 occultations in which the diffraction signal would be observable according to our criteria for star brightness and observation geometry. We find a mean amin =11 mm and a mean q=3.0. At both edges of the so-called "Strange" ringlet (R6) we find a mean amin = 20 mm and mean q values of 3.0 and 2.8 at the inner and outer edges, respectively. In contrast, we do not observe any clear diffraction signals at either edge of the wider Huygens ringlet. This could imply an absence of cm-scale or smaller particles and indicates that collisions here may be less vigorous than at the other ring edges analyzed in this study. We detect diffraction in a small fraction ( 10%) of occultations at 3 ringlets within the Cassini Division: the Herschel ringlet, the Laplace ringlet, and the Barnard ringlet. We

Vaginal prolapse repair with or without a midurethral sling in women with genital prolapse and occult stress urinary incontinence: a randomized trial.

Science.gov (United States)

van der Ploeg, J Marinus; Oude Rengerink, Katrien; van der Steen, Annemarie; van Leeuwen, Jules H Schagen; van der Vaart, C Huub; Roovers, Jan-Paul W R

2016-07-01

We compared pelvic organ prolapse (POP) repair with and without midurethral sling (MUS) in women with occult stress urinary incontinence (SUI). This was a randomized trial conducted by a consortium of 13 teaching hospitals assessing a parallel cohort of continent women with symptomatic stage II or greater POP. Women with occult SUI were randomly assigned to vaginal prolapse repair with or without MUS. Women without occult SUI received POP surgery. Main outcomes were the absence of SUI at the 12-month follow-up based on the Urogenital Distress Inventory and the need for additional treatment for SUI. We evaluated 231 women, of whom 91 randomized as follows: 43 to POP surgery with and 47 without MUS. A greater number of women in the MUS group reported absence of SUI [86 % vs. 48 %; relative risk (RR) 1.79; 95 % confidence interval (CI) 1.29-2.48]. No women in the MUS group received additional treatment for postoperative SUI; six (13 %) in the control group had a secondary MUS. Women with occult SUI reported more urinary symptoms after POP surgery and more often underwent treatment for postoperative SUI than women without occult SUI. Women with occult SUI had a higher risk of reporting SUI after POP surgery compared with women without occult SUI. Adding a MUS to POP surgery reduced the risk of postoperative SUI and the need for its treatment in women with occult SUI. Of women with occult SUI undergoing POP-only surgery, 13 % needed additional MUS. We found no differences in global impression of improvement and quality of life.

Neurogenic bladder from occult herpes zoster.

Science.gov (United States)

Rothrock, J F; Walicke, P A; Swenson, M R

1986-11-01

Active infection with herpes zoster may cause acute urinary retention, especially when it involves sacral dermatomes. Although frank retention usually develops days to weeks after eruption of the typical rash, bladder incompetence infrequently develops first, raising concern over other, more ominous etiologies. In the case presented, rash appearance was delayed until six weeks after the initial onset of urinary retention, a much longer interval than previously reported. Occult herpes zoster infection should be considered in patients presenting with an acute neurogenic bladder of obscure cause.

Verifying occulter deployment tolerances as part of NASA's technology development for exoplanet missions

Science.gov (United States)

Kasdin, N. J.; Lisman, D.; Shaklan, S.; Thomson, M.; Webb, D.; Cady, E.; Marks, G. W.; Lo, A.

2013-09-01

An external occulter is a satellite employing a large screen, or starshade, that flies in formation with a spaceborne telescope to provide the starlight suppression needed for detecting and characterizing exoplanets. Among the advantages of using an occulter are the broadband allowed for characterization and the removal of light before entering the observatory, greatly relaxing the requirements on the telescope and instrument. In support of NASA's Exoplanet Exploration Program and the Technology Development for Exoplanet Missions (TDEM), we recently completed a 2 year study of the manufacturability and metrology of starshade petals. In this paper we review the results of that successful first TDEM which demonstrated an occulter petal could be built and measured to an accuracy consistent with close to 10-10 contrast. We then present the results of our second TDEM to demonstrate the next critical technology milestone: precision deployment of the central truss and petals to the necessary accuracy. We show the deployment of an existing deployable truss outfitted with four sub-scale petals and a custom designed central hub.

Regulation of Tight Junctions in Upper Airway Epithelium

Directory of Open Access Journals (Sweden)

Takashi Kojima

2013-01-01

Full Text Available The mucosal barrier of the upper respiratory tract including the nasal cavity, which is the first site of exposure to inhaled antigens, plays an important role in host defense in terms of innate immunity and is regulated in large part by tight junctions of epithelial cells. Tight junction molecules are expressed in both M cells and dendritic cells as well as epithelial cells of upper airway. Various antigens are sampled, transported, and released to lymphocytes through the cells in nasal mucosa while they maintain the integrity of the barrier. Expression of tight junction molecules and the barrier function in normal human nasal epithelial cells (HNECs are affected by various stimuli including growth factor, TLR ligand, and cytokine. In addition, epithelial-derived thymic stromal lymphopoietin (TSLP, which is a master switch for allergic inflammatory diseases including allergic rhinitis, enhances the barrier function together with an increase of tight junction molecules in HNECs. Furthermore, respiratory syncytial virus infection in HNECs in vitro induces expression of tight junction molecules and the barrier function together with proinflammatory cytokine release. This paper summarizes the recent progress in our understanding of the regulation of tight junctions in the upper airway epithelium under normal, allergic, and RSV-infected conditions.

Paraneoplastic retinopathy associated with occult bladder cancer

DEFF Research Database (Denmark)

Nivean, M; Muttuvelu, Danson V; Afzelius, Pia Maria Tullia

2016-01-01

(ERG), serology including serum antibodies for CAR, and positron emission tomography-computed tomography (PET-CT) scan. The patient was diagnosed with bladder carcinoma revealed by PET-CT. Timely recognition of this entity may be crucial for an increased patient survival thus adult onset progressive...... photoreceptor dysfunction, confirmed by ERG, should alert to a possible remote effect of known or occult malignancy. In the latter, PET-CT may be exploited as a powerful diagnostic tool....

Occult microscopic endometriosis: undetectable by laparoscopy in normal peritoneum.

Science.gov (United States)

Khan, Khaleque Newaz; Fujishita, Akira; Kitajima, Michio; Hiraki, Koichi; Nakashima, Masahiro; Masuzaki, Hideaki

2014-03-01

Is there any occurrence of hidden (occult) endometriotic lesions in normal peritoneum of women with and without visible endometriosis? We detected a slightly higher occurrence of occult microscopic endometriosis (OME) in normal peritoneum of women with visible endometriosis than in control women. Based on a small number of cases, the concept of invisible microscopic endometriosis in visually normal peritoneum has been reported for more than a decade but there is controversy regarding their tissue activity and clinical significance. This case-controlled research study was conducted with prospectively collected normal peritoneal samples from 151 women with and 62 women without visible endometriosis. Normal peritoneal biopsy specimens from different pelvic sites of were collected during laparoscopy. A histological search of all peritoneal biopsy specimens for the detection of invisible endometriosis was done by immunoreaction to Ber-EP4 (epithelial cell marker), CD10 (stromal cell marker) and Calretinin (mesothelial cell marker). Tissue expression of estrogen/progesterone receptors (ER/PR) and cell proliferation marker, Ki-67, was performed by immunohistochemistry to identify tissue activity. Three different patterns of OME were detected based on (I) the presence of typical gland/stroma, (II) reactive hyperplastic change of endometrioid epithelial cells with surrounding stroma and (III) single-layered epithelium-lined cystic lesions with surrounding stroma. A higher tendency toward the occurrence of OME was found in women with visible endometriosis (15.2%, 23/151) compared with control women (6.4%, 4/62) (P = 0.06, χ(2) test). The epithelial cells and/or stromal cells of OME lesions were immunoreactive to Ber-EP4 and CD10 but not reactive to Calretinin. ER and PR expression was observed in all patterns of OME lesions. Ki-67 index was significantly higher in pattern I/II OME lesions than in pattern III OME lesions (Pendometriosis due to the presence of adhesions in

Male occult triple-negative breast cancer with dermatomyositis: a case report and review of the literature

Directory of Open Access Journals (Sweden)

Zhang L

2017-11-01

Full Text Available Le Zhang,1 Chenghua Zhang,2 Zhaoying Yang,1 Miao He,3 Lijuan Zhang,1 Shereen Ezzat,4 Xi Liang5 1Department of Breast Surgery, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China; 2Endoscopy Department, Jilin Cancer Hospital, Changchun, Jilin,China; 3Department of Anesthesia, The Second Hospital of Jilin University, Changchun, Jilin, China; 4Ontario Cancer Institute and The Endocrine Oncology Site Group, Princess Margaret Hospital, University Health Network, Toronto, Ontario, Canada; 5Department of Breast Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China Abstract: Occult breast cancer is defined by the presence of axillary metastases without an identifiable primary breast tumor. Here, we report a rare case of a male occult breast cancer with dermatomyositis. We performed a modified radical mastectomy consisting of whole breast mastectomy and axillary lymph node dissection. Immunohistochemistry and fluorescent in situ hybridization analyses demonstrated an adenocarcinoma likely of breast origin, which was an occult triple-negative breast cancer. Interestingly, the patient’s previously noted periorbital dermatomyositis resolved promptly following surgical excision. Keywords: male breast cancer, occult breast cancer, triple-negative breast cancer, dermato­myositis 

Occult Metabolic Bone Disease in Chronic Pancreatitis | Hari Kumar ...

African Journals Online (AJOL)

Background: Chronic pancreatitis (CP) leads to malabsorption and metabolic bone disease (MBD). Alcoholic CP (ACP) and tropical CP (TCP) are the two common types of CP. Objective: We investigated the presence of occult MBD in patients with CP and compared the same between ACP and TCP. Materials and Methods: ...

The ionosphere of Europa from Galileo radio occultations

Science.gov (United States)

Kliore, A. J.; Hinson, D. P.; Flasar, F. M.; Nagy, A. F.; Cravens, T. E.

1997-01-01

The Galileo spacecraft performed six radio occultation observations of Jupiter's Galilean satellite Europa during its tour of the jovian system. In five of the six instances, these occultations revealed the presence of a tenuous ionosphere on Europa, with an average maximum electron density of nearly 10(4) per cubic centimeter near the surface and a plasma scale height of about 240 +/- 40 kilometers from the surface to 300 kilometers and of 440 +/- 60 kilometers above 300 kilometers. Such an ionosphere could be produced by solar photoionization and jovian magnetospheric particle impact in an atmosphere having a surface density of about 10(8) electrons per cubic centimeter. If this atmosphere is composed primarily of O2, then the principal ion is O2+ and the neutral atmosphere temperature implied by the 240-kilometer scale height is about 600 kelvin. If it is composed of H2O, the principal ion is H3O+ and the neutral temperature is about 340 kelvin. In either case, these temperatures are much higher than those observed on Europa's surface, and an external heating source from the jovian magnetosphere is required.

Observing Tropospheric Water Vapor by Radio Occultation using the Global Positioning System

Science.gov (United States)

Kursinski, E. R.; Hajj, G. A.; Hardy, K. R.; Romans, L. J.; Schofield, J. T.

1995-01-01

Given the importance of water vapor to weather, climate and hydrology, global humidity observations from satellites are critical. At low latitudes, radio occultation observations of Earth's atmosphere using the Global Positioning System (GPS) satellites allow water vapor profiles to be retrieved with accuracies of 10 to 20% below 6 to 7 km altitude and approx. 5% or better within the boundary layer. GPS observations provide a unique combination of accuracy, vertical resolution (less than or equal to 1 km) and insensitivity to cloud and aerosol particles that is well suited to observations of the lower troposphere. These characteristics combined with the inherent stability of radio occultation observations make it an excellent candidate for the measurement of long term trends.

Photometry of occultation candidate stars. I - Uranus 1985 and Saturn 1985-1991

Science.gov (United States)

French, L. M.; Morales, G.; Dalton, A. S.; Klavetter, J. J.; Conner, S. R.

1985-01-01

Photometric observations of five stars to be occulted by the rings around Uranus are presented. The four stars to be occulted by Saturn or its rings during the period 1985-1991 were also observed. The observations were carried out with a CCD detector attached to the Kitt Peak McGraw-Hill 1.30-m telescope. Landolt standards of widely ranging V-I color indices were used to determine the extinction coefficients, transformation coefficients, and zero points of the stars. Mean extinction coefficients are given for each night of observation. K magnitudes for each star were estimated on the basis of the results of Johnson (1967). The complete photometric data set is given in a series of tables.

Molecular and serological detection of occult hepatitis B virus ...

African Journals Online (AJOL)

hepatitis B surface antigen-negative blood donors in Malaysia. ... Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface .... of the standard HBV-positive serum and the detection ... in general population ranges from 1.5 to 9.8% but report- .... Putra, Malaysia for their financial support of this research.

Steam and electroheating remediation of tight soils

Energy Technology Data Exchange (ETDEWEB)

Balshaw-Biddle, K.; Oubre, C.L.; Ward, C.H. [eds.; Dablow, J.F. III; Pearce, J.A.; Johnson, P.C.

2000-07-01

In the past few decades the need for soil remediation has become urgent, even more necessary--innovative, cost effective methods. Steam and Electroheating Remediation of Tight Soils presents the results of a field study testing the cleanup of semi-volatile fuels from tight soils using combination of hydraulic fracturing and soil heating technologies.

Do X-ray-occult fractures play a role in chronic pain following a whiplash injury?

DEFF Research Database (Denmark)

Hertzum-Larsen, Rasmus; Petersen, Henrik; Kasch, Helge

2014-01-01

symptoms following an MVA was invited to have a cervical SPECT shortly post injury and again 6 months later. Associations between occult fractures and pain levels at baseline, 6 and 12 months of follow-up were analyzed. Eighty-eight patients had baseline SPECT performed at median 15 days (range 3-28) post......Whiplash trauma in motor vehicle accidents (MVA) may involve various painful soft tissue damages, but weeks/months later a minority of victims still suffers from various long-lasting and disabling symptoms, whiplash-associated disorders (WAD). The etiology is currently unknown, but X......-ray-occult fractures may be one cause in some cases. The purpose of this prospective study was to examine the association between occult fractures, as seen on bone single photon emission computed tomography (SPECT), with neck-, head- and arm pain. An inception cohort of 107 patients presenting with acute whiplash...

An introduction to finite tight frames

CERN Document Server

Waldron, Shayne F D

2018-01-01

This textbook is an introduction to the theory and applications of finite tight frames, an area that has developed rapidly in the last decade. Stimulating much of this growth are the applications of finite frames to diverse fields such as signal processing, quantum information theory, multivariate orthogonal polynomials, and remote sensing. Key features and topics: * First book entirely devoted to finite frames * Extensive exercises and MATLAB examples for classroom use * Important examples, such as harmonic and Heisenberg frames, are presented in preliminary chapters, encouraging readers to explore and develop an intuitive feeling for tight frames * Later chapters delve into general theory details and recent research results * Many illustrations showing the special aspects of the geometry of finite frames * Provides an overview of the field of finite tight frames * Discusses future research directions in the field Featuring exercises and MATLAB examples in each chapter, the book is well suited as a textbook ...

[Management of occult malformations at the lateral skull base].

Science.gov (United States)

Bryson, E; Draf, W; Hofmann, E; Bockmühl, U

2005-12-01

Occult malformations of the lateral skull base are rare anomalies, but can cause severe complications such as recurrent meningitis. Therefore, they need to be precisely delineated and sufficient surgical closure is mandatory. Between 1986 and 2004 twenty patients (10 children and 10 adults) with occult malformations at the lateral skull base were treated surgically at the ENT-Department of the Hospital Fulda gAG. Of these 3 Mondini-malformations, 11 defects of the tegmen tympani or the mastoidal roof, 2 dural lesions to the posterior fossa and 4 malformations within the pyramidal apex have been found. Four patients have had multiple anomalies. Routing symptom was in all cases at least one previous meningitis. Radiological diagnostics included high-resolution computed tomography (CT) and magnetic resonance imaging (MRI) as well as CT- or MR-cisternography. Depending on type and localisation of the defect the following surgical algorithm was carried out: The trans-mastoidal approach was used in all cases of Mondini-malformation (including obliteration of the ear), in case of lesions to the posterior fossa as well as partly in anomalies at the tegmen tympani and mastoidal roof, respectively. Defects of the pyramidal apex should be explored via the trans-mastoidal way if the lesion is located caudally to the inner auditory canal (IAC), whereas the trans-temporal approach should be used if the lesion is situated ventral to the IAC and dorso-medially to the internal carotid artery (ICA). The trans-temporal approach was also performed in large defects of the tegmen tympani and mastoidal roof as well as in recurrences. In all cases of recurrent meningitis caused by agents of the upper airway tract the basic principle should be to search for occult skull base malformations radiologically as well as by sodium fluorescein endoscopy as long as the anomaly is detected.

Tight or sick building syndrome

Energy Technology Data Exchange (ETDEWEB)

Thirumalaikolundusubramanian, P; Shanmuganadan, S [Madurai Kamaraj Univ. (India). Dept. of Geography; Uma, A [Madurai Medical Coll. (India). Dept. of Medicine and Microbiology

1991-01-01

Modern buildings are designed with the usual heating, air-conditioning and ventilation equipment. In most of these buildings, air is continuously recirculated and, as a result, workers suffer from tight or sick building syndrome. This syndrome is discussed with reference to symptoms of air contamination, ventilation system standards and research needs. The most common symptoms of tight building syndrome are eye, nose and throat irritation, headache, fatigue, sneezing, difficulty in wearing contact lenses, chest tightness, nausea, dizziness and dermatitis. Symptoms experienced by 50 doctors and 50 paramedical personnel working in an air-conditioned intensive care unit and operating theatres of the Government Rajaji Hospital, Madurai in India were studied by means of a questionnaire survey. In the present study, respiratory and ocular symptoms were observed more in those working in operating theatres and were believed to be due to excessive use of formaldehyde used for sterilization. Various suggestions were made to prevent sick building syndrome. Moreover, the physicians treating sick individuals should be aware of the symptoms caused by indoor air pollutants as sufferers invariably require a change of environment rather than drugs. (orig.).

Prevalence of Visible and Occult Blood on the Surfaces of Fiberoptic Bronchoscopes

National Research Council Canada - National Science Library

McKamey, Jeffrey

2000-01-01

.... This study was conducted to determine if current cleaning, disinfection and sterilization procedures used at one medical center was adequate to remove visible and occult blood from fiberoptic bronchoscopes...

Occult Invasive Lobular Carcinoma of Breast Detected by Stomach Metastasis: A Case Report

International Nuclear Information System (INIS)

KIm, So Jung; Jung, Hae Kyoung; Ko, Kyung Hee; Yoon, Jung Hyun

2012-01-01

Gastric metastasis from primary breast cancer is a rare phenomenon that is more prevalent in the invasive lobular type of breast cancer. We describe a very rare case of occult invasive lobular cancer of the breast detected by the initial presentation of gastric metastasis in a patient without a history of breast cancer. A 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) which showed increased FDG uptake in the stomach, abdominal mesentery and the right breast, and played pivotal roles in the detection of occult primary breast cancer and a diagnosis of gastric metastasis as an ancillary method for obtaining histological results and immunohistochemical stains.

Occult Invasive Lobular Carcinoma of Breast Detected by Stomach Metastasis: A Case Report

Energy Technology Data Exchange (ETDEWEB)

KIm, So Jung; Jung, Hae Kyoung; Ko, Kyung Hee; Yoon, Jung Hyun [Dept. of Radiology, Bundang CHA general Hospital, CHA University College of Medicine, Seongnam (Korea, Republic of)

2012-02-15

Gastric metastasis from primary breast cancer is a rare phenomenon that is more prevalent in the invasive lobular type of breast cancer. We describe a very rare case of occult invasive lobular cancer of the breast detected by the initial presentation of gastric metastasis in a patient without a history of breast cancer. A 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) which showed increased FDG uptake in the stomach, abdominal mesentery and the right breast, and played pivotal roles in the detection of occult primary breast cancer and a diagnosis of gastric metastasis as an ancillary method for obtaining histological results and immunohistochemical stains.

Image guidance improves localization of sonographically occult colorectal liver metastases

Science.gov (United States)

Leung, Universe; Simpson, Amber L.; Adams, Lauryn B.; Jarnagin, William R.; Miga, Michael I.; Kingham, T. Peter

2015-03-01

Assessing the therapeutic benefit of surgical navigation systems is a challenging problem in image-guided surgery. The exact clinical indications for patients that may benefit from these systems is not always clear, particularly for abdominal surgery where image-guidance systems have failed to take hold in the same way as orthopedic and neurosurgical applications. We report interim analysis of a prospective clinical trial for localizing small colorectal liver metastases using the Explorer system (Path Finder Technologies, Nashville, TN). Colorectal liver metastases are small lesions that can be difficult to identify with conventional intraoperative ultrasound due to echogeneity changes in the liver as a result of chemotherapy and other preoperative treatments. Interim analysis with eighteen patients shows that 9 of 15 (60%) of these occult lesions could be detected with image guidance. Image guidance changed intraoperative management in 3 (17%) cases. These results suggest that image guidance is a promising tool for localization of small occult liver metastases and that the indications for image-guided surgery are expanding.

The use of MRI and CT in Imaging Occult Hip Fractures

Directory of Open Access Journals (Sweden)

Obadă B.

2014-11-01

Full Text Available Diagnosis of hip fractures is particularly important due to the high dependence on the integrity of this structure for people to function in their daily lives. Left unrecognized, patients face increasing morbidity and mortality as time from the original injury lengthens. A delay of just 2 days in surgical treatment for an acute hip fracture doubles mortality. In addition, an unrecognized non-displaced fracture may displace, requiring surgery of much higher risk. This may be part of the reason that the most frequent lawsuit against Emergency Physicians is for missed orthopedic injury. We reviewed the use of MRI and CT for occult hip fractures (OHF detection at a major urban trauma unit. Our study is a retrospective review. Inclusion criteria: all patients presenting to the Emergency Clinical Hospital of Constanta with a suspected, posttraumatic, occult hip fracture, over a 5 years period were included. All patients had negative initial radiographs and underwent further imaging with either CT or MRI. A total of 185 cases meeting the inclusion criteria were identified. 72 occult hip fractures were detected with both imaging modalities. Although MRI certainly enables greater image detail, in our experience both modalities are able to provide satisfactory fracture characterization. The choice of imaging should be determined by availability and indication. MRI provides superior imaging of soft tissue but is less sensitive for degenerative changes in presence of bone edema.

Dielectric response of molecules in empirical tight-binding theory

Science.gov (United States)

Boykin, Timothy B.; Vogl, P.

2002-01-01

In this paper we generalize our previous approach to electromagnetic interactions within empirical tight-binding theory to encompass molecular solids and isolated molecules. In order to guarantee physically meaningful results, we rederive the expressions for relevant observables using commutation relations appropriate to the finite tight-binding Hilbert space. In carrying out this generalization, we examine in detail the consequences of various prescriptions for the position and momentum operators in tight binding. We show that attempting to fit parameters of the momentum matrix directly generally results in a momentum operator which is incompatible with the underlying tight-binding model, while adding extra position parameters results in numerous difficulties, including the loss of gauge invariance. We have applied our scheme, which we term the Peierls-coupling tight-binding method, to the optical dielectric function of the molecular solid PPP, showing that this approach successfully predicts its known optical properties even in the limit of isolated molecules.

Spatial patterns of whole brain grey and white matter injury in patients with occult spastic diplegic cerebral palsy.

Science.gov (United States)

Mu, Xuetao; Nie, Binbin; Wang, Hong; Duan, Shaofeng; Zhang, Zan; Dai, Guanghui; Ma, Qiaozhi; Shan, Baoci; Ma, Lin

2014-01-01

Spastic diplegic cerebral palsy (SDCP) is a common type of cerebral palsy (CP), which presents as a group of motor-impairment syndromes. Previous conventional MRI studies have reported abnormal structural changes in SDCP, such as periventricular leucomalacia. However, there are roughly 27.8% SDCP patients presenting normal appearance in conventional MRI, which were considered as occult SDCP. In this study, sixteen patients with occult SDCP and 16 age- and sex-matched healthy control subjects were collected and the data were acquired on a 3T MR system. We applied voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) analysis to investigate whole brain grey and white matter injury in occult SDCP. By using VBM method, the grey matter volume reduction was revealed in the bilateral basal ganglia regions, thalamus, insula, and left cerebral peduncle, whereas the white matter atrophy was found to be located in the posterior part of corpus callosum and right posterior corona radiata in the occult SDCP patients. By using TBSS, reduced fractional anisotropy (FA) values were detected in multiple white matter regions, including bilateral white matter tracts in prefrontal lobe, temporal lobe, internal and external capsule, corpus callosum, cingulum, thalamus, brainstem and cerebellum. Additionally, several regions of white matter tracts injury were found to be significantly correlated with motor dysfunction. These results collectively revealed the spatial patterns of whole brain grey and white matter injury in occult SDCP.

Occulting Light Concentrators in Liquid Scintillator Neutrino Detectors

Science.gov (United States)

Buizza Avanzini, Margherita; Cabrera, Anatael; Dusini, Stefano; Grassi, Marco; He, Miao; Wu, Wenjie

2017-09-01

The experimental efforts characterizing the era of precision neutrino physics revolve around collecting high-statistics neutrino samples and attaining an excellent energy and position resolution. Next generation liquid-based neutrino detectors, such as JUNO, HyperKamiokande, etc, share the use of a large target mass, and the need of pushing light collection to the edge for maximal calorimetric information. Achieving high light collection implies considerable costs, especially when considering detector masses of several kt. A traditional strategy to maximize the effective photo-coverage with the minimum number of PMTs relies on Light Concentrators (LC), such as Winston Cones. In this paper, the authors introduce a novel concept called Occulting Light Concentrators (OLC), whereby a traditional LC gets tailored to a conventional PMT, by taking into account its single-photoelectron collection efficiency profile and thus occulting the worst performing portion of the photocathode. Thus, the OLC shape optimization takes into account not only the optical interface of the PMT, but also the maximization of the PMT detection performances. The light collection uniformity across the detector is another advantage of the OLC system. By considering the case of JUNO, we will show OLC capabilities in terms of light collection and energy resolution.

Ex Luna Scientia: The Lunar Occultation Explorer (LOX)

Science.gov (United States)

Miller, Richard

2017-01-01

The Lunar Occultation Explorer (LOX) is a next-generation mission concept that provides new capabilities for time-domain astrophysics and established the Moon as a platform for nuclear astrophysics. Performance requirements are driven by Type-Ia supernova (SNeIa) science goals that seek to revel details of these profoundly radioactive objects, including their diversity. Primary science objectives include, but are not limited to, probing the fundamental thermonuclear physics processes, performing a census of progenitors and their explosion mechanisms, and evaluating the environmental conditions and intrinsic systematics of these enigmatic objects. LOX provides new capabilities for all-sky, continuous monitoring in the MeV regime (0.1-10 MeV) by leveraging the Lunar Occultation Technique (LOT). Key benefits of the LOX/LOT approach include maximizing the ratio of sensitive-to-total deployed mass, low implementation risk, and demonstrated operational simplicity that leverages extensive experience with planetary orbital geochemistry investigations; LOX also enables long-term monitoring of MeV gamma-ray sources, a critical capability for SNeIa science. Proof-of-principle efforts validated all aspects of the mission using previously deployed lunar science assets, and led to the first high-energy gamma-ray source detected at the Moon. LOX mission performance, development progress, and expectations for science investigations will be presented.

Detection of occult HBV infection by nested PCR assay among ...

African Journals Online (AJOL)

Occult hepatitis B virus infection (OBI) has been reported among patients with chronic hepatitis C virus (HCV) infection and hepatocellular carcinoma (HCC). This study aimed to evaluate the prevalence of OBI in chronic hepatitis C patients with and without hepatocellular carcinoma. A total of 40 chronic hepatitis C patients ...

THE 2011 JUNE 23 STELLAR OCCULTATION BY PLUTO: AIRBORNE AND GROUND OBSERVATIONS

Energy Technology Data Exchange (ETDEWEB)

Person, M. J.; Bosh, A. S.; Levine, S. E.; Gulbis, A. A. S.; Zangari, A. M.; Zuluaga, C. A.; Sallum, S. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139-4307 (United States); Dunham, E. W.; Collins, P.; Bida, T.; Bright, L. [Lowell Observatory, Flagstaff, AZ (United States); Pasachoff, J. M.; Babcock, B. A.; Pandey, S.; Amrhein, D. [Williams College-Hopkins Observatory, Williamstown, MA (United States); Tholen, D. J. [Institute for Astronomy, University of Hawaii, Manoa, HI (United States); Taylor, B. [Boston University, Boston, MA (United States); Wolf, J.; Pfueller, E. [Deutsches SOFIA Institut, Universitaet Stuttgart, Pfaffenwaldring 29, D-70569 Stuttgart (Germany); Meyer, A., E-mail: mjperson@mit.edu [SOFIA Science Center, NASA Ames Research Center, MS 211-1, Moffett Field, CA 94035 (United States); and others

2013-10-01

On 2011 June 23, stellar occultations by both Pluto (this work) and Charon (future analysis) were observed from numerous ground stations as well as the Stratospheric Observatory for Infrared Astronomy (SOFIA). This first airborne occultation observation since 1995 with the Kuiper Airborne Observatory resulted in the best occultation chords recorded for the event, in three visible wavelength bands. The data obtained from SOFIA are combined with chords obtained from the ground at the IRTF, the U.S. Naval Observatory Flagstaff Station, and Leeward Community College to give the detailed state of the Pluto-Charon system at the time of the event with a focus on Pluto's atmosphere. The data show a return to the distinct upper and lower atmospheric regions with a knee or kink in the light curve separating them as was observed in 1988, rather than the smoothly transitioning bowl-shaped light curves of recent years. The upper atmosphere is analyzed by fitting a model to all of the light curves, resulting in a half-light radius of 1288 {+-} 1 km. The lower atmosphere is analyzed using two different methods to provide results under the differing assumptions of particulate haze and a strong thermal gradient as causes for the lower atmospheric diminution of flux. These results are compared with those from past occultations to provide a picture of Pluto's evolving atmosphere. Regardless of which lower atmospheric structure is assumed, results indicate that this part of the atmosphere evolves on short timescales with results changing the light curve structures between 1988 and 2006, and then reverting these changes in 2011 though at significantly higher pressures. Throughout these changes, the upper atmosphere remains remarkably stable in structure, again except for the overall pressure changes. No evidence of onset of atmospheric collapse predicted by frost migration models is seen, and the atmosphere appears to be remaining at a stable pressure level, suggesting it

Verify Occulter Deployment Tolerances as Part of NASA's Technology Development for Exoplanet Missions

Science.gov (United States)

Kasdin, N. J.; Shaklan, S.; Lisman, D.; Thomson, M.; Webb, D.; Cady, E.; Marks, G. W.; Lo, A.

2013-01-01

In support of NASA's Exoplanet Exploration Program and the Technology Development for Exoplanet Missions (TDEM), we recently completed a 2 year study of the manufacturability and metrology of starshade petals. An external occult is a satellite employing a large screen, or starshade, that flies in formation with a spaceborne telescope to provide the starlight suppression needed for detecting and characterizing exoplanets. Among the advantages of using an occulter are the broadband allowed for characterization and the removal of light before entering the observatory, greatly relaxing the requirements on the telescope and instrument. This poster presents the results of our successful first TDEM that demonstrated an occulter petal could be built and measured to an accuracy consistent with close to 10^-10 contrast. We also present the progress in our second TDEM to demonstrate the next critical technology milestone: precision deployment of the central truss and petals to the necessary accuracy. We have completed manufacture of four sub-scale petals and a central hub to fit with an existing deployable truss. We show the plans for repeated stow and deploy tests of the assembly and the metrology to confirm that each deploy repeatably meets the absolute positioning requirements of the petals (better than 1.0 mm).

Metastatic Squamous Neck Cancer with Occult Primary Treatment (PDQ®)—Patient Version

Science.gov (United States)

Metastatic squamous neck cancer with occult primary (unknown primary) treatment options include surgery, radiation therapy, or a combination of both. Learn more about the diagnosis and treatment of these tumors in this expert-reviewed summary.

Lunar occultation of the Galactic center at 2.2 microns

NARCIS (Netherlands)

Adams, D. J.; Becklin, E. E.; Jameson, R. F.; Longmore, A. J.; Sandqvist, Aa.; Valentijn, E.

1988-01-01

Results of the lunar occultation of IRS 16 on 1986 September 11 are reported. Sixty percent of the observed flux in a 6arcsec.5 beam comes from four discrete sources. Three sources are unresolved pointlike objects (<0arcsec.05) and are assumed to be individual stars. The fourth object is well

Past and future of radio occultation studies of planetary atmospheres

Science.gov (United States)

Eshleman, Von R.; Hinson, David P.; Tyler, G. Leonard; Lindal, Gunnar F.

1987-01-01

Measurements of radio waves that have propagated through planetary atmospheres have provided exploratory results on atmospheric constituents, structure, dynamics, and ionization for Venus, Mars, Titan, Jupiter, Saturn, and Uranus. Highlights of past results are reviewed in order to define and illustrate the potential of occultation and related radio studies in future planetary missions.

'Trick', 'manipulation' and 'farce': Albert Moll's critique of occultism.

Science.gov (United States)

Wolffram, Heather

2012-04-01

In July 1925, the psychiatrist Albert Moll appeared before the district court in Berlin-Schöneberg charged with having defamed the medium Maria Vollhardt (alias Rudloff) in his 1924 book Der Spiritismus [Spiritism]. Supported by some of Berlin's most prominent occultists, the plaintiff--the medium's husband--argued that Moll's use of terms such as 'trick', 'manipulation' and 'farce' in reference to Vollhardt's phenomena had been libellous. In the three-part trial that followed, however, Moll's putative affront to the medium--of which he was eventually acquitted--was overshadowed, on the one hand, by a debate over the scientific status of parapsychology, and on the other, by the question of who--parapsychologists, occultists, psychiatrists or jurists--was entitled to claim epistemic authority over the occult. This paper will use the Rudloff-Moll trial as a means of examining Moll's critique of occultism, not only as it stood in the mid-1920s, but also as it had developed since the 1880s. It will also provide insight into the views of Germany's occultists and parapsychologists, who argued that their legitimate bid for scientific credibility was hindered by Dunkelmänner [obscurantists] such as Albert Moll.

The floating cardiac fat pad-sign of occult pneumothorax.

Science.gov (United States)

Kaufman, Claire; Bokhari, S A Jamal

2016-08-01

Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.

Esophageal Metastasis From Occult Lung Cancer

Directory of Open Access Journals (Sweden)

Po-Kuei Hsu

2010-06-01

Full Text Available A 66-year-old man with dysphagia was found to have a poorly differentiated esophageal carcinoma by incision biopsy. Following esophagectomy, reconstruction with a gastric tube was performed. Pathological examination and immunohisto-chemistry showed infiltration of adenocarcinoma cells with positive thyroid transcription factor 1-staining in the submucosal layer, which indicated metastatic esophageal carcinoma. Although no pulmonary lesion could be visualized by imaging or bronchoscopy, pulmonary origin was highly suspected as a result of positive thyroid transcription factor 1-staining. To the best of our knowledge, this is the first reported case of metastatic esophageal carcinoma from occult lung cancer (AJCC TNM stage TX.

Local time dependence of the thermal structure in the Venusian equatorial region revealed by Akatsuki radio occultation measurements

Science.gov (United States)

Ando, H.; Fukuhara, T.; Takagi, M.; Imamura, T.; Sugimoto, N.; Sagawa, H.

2017-12-01

The radio occultation technique is one of the most useful methods to retrieve vertical temperature profiles in planetary atmospheres. Ultra-Stable Oscillator (USO) onboard Venus Climate Orbiter, Akatsuki, enables us to investigate the thermal structure of the Venus atmosphere between about 40-90 km levels. It is expected that 35 temperature profiles will be obtained by the radio occultation measurements of Akatsuki until August 2017. Static stability derived from the temperature profiles shows its local time dependence above the cloud top level at low-latitudes equatorward of 25˚. The vertical profiles of the static stability in the dawn and dusk regions have maxima at 77 km and 82 km levels, respectively. A general circulation model (GCM) for the Venus atmosphere (AFES-Venus) reproduced the thermal structures above the cloud top qualitatively consistent with the radio occultation measurements; the maxima of the static stability are seen both in the dawn and dusk regions, and the local maximum of the static stability in the dusk region is located at a highler level than in the dawn region. Comparing the thermal structures between the radio occultation measurements and the GCM results, it is suggested that the distribution of the static stability above the cloud top could be strongly affected by the diurnal tide. The thermal tide influences on the thermal structure as well as atmospheric motions above the cloud level. In addition, it is shown that zonally averaged zonal wind at about 80 km altitude could be roughly estimated from the radio occultation measurements using the dispersion relation of the internal gravity wave.

External occulter edge scattering control using metamaterials for exoplanet detection

Science.gov (United States)

Bendek, Eduardo A.; Sirbu, Dan; Liu, Zhaowei; Martin, Stefan; Lu, Dylan

2015-09-01

Direct imaging of earth-like exoplanets in the Habitable Zone of sun-like stars requires image contrast of ~10^10 at angular separations of around a hundred milliarcseconds. One approach for achieving this performance is to fly a starshade at a long distance in front of the telescope, shading the telescope from the direct starlight, but allowing planets around the star to be seen. The starshade is positioned so that sunlight falls on the surface away from the telescope, so the sun does not directly illuminate it. However, sunlight scattered from the starshade edge can enter the telescope, raising the background light level and potentially preventing the starshade from delivering the required contrast. As a result, starshade edge design has been identified as one of the highest priority technology gaps for external occulter missions in the NASAs Exoplanet Exploration Program Technology Plan 2013. To reduce the sunlight edge scatter to an acceptable level, the edge Radius Of Curvature (ROC) should be 1μm or less (commercial razor blades have ROC of a few hundred nanometer). This poses a challenging manufacturing requirement and may make the occulter difficult to handle. In this paper we propose an alternative approach to controlling the edge scattering by applying a flexible metamaterial to the occulter edge. Metamaterials are artificially structured materials, which have been designed to display properties not found in natural materials. Metamaterials can be designed to direct the scatter at planned incident angles away from the space telescope, thereby directly decreasing the contaminating background light. Reduction of the background light translates into shorter integration time to characterize a target planet and therefore improves the efficiency of the observations. As an additional benefit, metamaterials also have potential to produce increased tolerance to edge defects.

Improved Density Functional Tight Binding Potentials for Metalloid Aluminum Clusters

Science.gov (United States)

2016-06-01

unlimited IMPROVED DENSITY-FUNCTIONAL TIGHT BINDING POTENTIALS FOR METALLOID ALUMINUM CLUSTERS by Joon H. Kim June 2016 Thesis Advisor...DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE IMPROVED DENSITY-FUNCTIONAL TIGHT BINDING POTENTIALS FOR METALLOID ALUMINUM CLUSTERS 5. FUNDING...repulsive potentials for use in density-functional tight binding (DFTB) simulations of low-valence aluminum metalloid clusters . These systems are under

Retrieval of temperature and pressure using broadband solar occultation: SOFIE approach and results

Directory of Open Access Journals (Sweden)

B. T. Marshall

2011-05-01

Full Text Available Measurement of atmospheric temperature as a function of pressure, T(P, is key to understanding many atmospheric processes and a prerequisite for retrieving gas mixing ratios and other parameters from solar occultation measurements. This paper gives a brief overview of the solar occultation measurement technique followed by a detailed discussion of the mechanisms that make the measurement sensitive to temperature. Methods for retrieving T(P using both broadband transmittance and refraction are discussed. Investigations using measurements of broadband transmittance in two CO₂ absorption bands (the 4.3 and 2.7 μm bands and refractive bending are then presented. These investigations include sensitivity studies, simulated retrieval studies, and examples from SOFIE.

The Centaur Chariklo and its rings system from stellar occultations in 2017

Science.gov (United States)

Leiva, Rodrigo; Sicardy, Bruno; Camargo, Julio; Ortiz, Jose Luis; Berard, Diane; Desmars, Josselin; Chariklo Occultations Team; Rio Group; Lucky Star Occultation Team; Granada Occultation Team

2017-10-01

A stellar occultation in June 3, 2013 revealed the presence of a dense ring system around the Centaur object (10199) Chariklo (Braga-Ribas et al., Nature 2014). Subsequent analysis of occultation data and long-term photometric variations indicate that Chariklo's body is elongated (Leiva et al. 2017, submitted) and that the main ring exhibits significant longitudinal variations of the radial width (Bérard et al. 2017, in press). We report three multi-chord high-quality stellar occultation by Chariklo on April 9, 2017 and June 22, 2017 from Namibia, and July 23 2017 from South America. The analysis of this new data set is underway, but preliminary results are consistent with triaxial ellipsoidal models. From this analysis we will:-present refined models for the size and shape of Chariklo's main body andevaluate the heights and slopes of its topographic features.-give constraints on the longitudinal width variations of Chariklo's rings andexplore the possibility to obtain the rings apsidal precession rate.Chariklo's shape and topography have strong consequences on the dynamics of the rings through Lindblad-type resonances between mean motion of the ring particles and the spin of the main body, while the rings precession rate gives constraints on the dynamical oblateness of the main body.**Part of the research leading to these results has received funding from the European Research Council under the European Community’s H2020 (2014-2020/ ERC Grant Agreement n 669416 ”LUCKY STAR”).

Implementation of immunochemical faecal occult blood test in general practice

DEFF Research Database (Denmark)

Juul, Jakob Søgaard; Bro, Flemming; Hornung, Nete

2016-01-01

anvendelsen af immunochemical faecal occult blood test (iFOBT) i almen praksis. iFOBT detekterer humant globin i fæces og indikerer gastrointestinal blødning. Studiet udgør en del af et ph.d.-studie, der bidrager med ny viden til at optimere udredningen af patienter med tarmkræft. Der er et stort behov...

Human zonulin, a potential modulator of intestinal tight junctions.

Science.gov (United States)

Wang, W; Uzzau, S; Goldblum, S E; Fasano, A

2000-12-01

Intercellular tight junctions are dynamic structures involved in vectorial transport of water and electrolytes across the intestinal epithelium. Zonula occludens toxin derived from Vibrio cholerae interacts with a specific intestinal epithelial surface receptor, with subsequent activation of a complex intracellular cascade of events that regulate tight junction permeability. We postulated that this toxin may mimic the effect of a functionally and immunologically related endogenous modulator of intestinal tight junctions. Affinity-purified anti-zonula occludens toxin antibodies and the Ussing chamber assay were used to screen for one or more mammalian zonula occludens toxin analogues in both fetal and adult human intestine. A novel protein, zonulin, was identified that induces tight junction disassembly in non-human primate intestinal epithelia mounted in Ussing chambers. Comparison of amino acids in the active zonula occludens toxin fragment and zonulin permitted the identification of the putative receptor binding domain within the N-terminal region of the two proteins. Zonulin likely plays a pivotal role in tight junction regulation during developmental, physiological, and pathological processes, including tissue morphogenesis, movement of fluid, macromolecules and leukocytes between the intestinal lumen and the interstitium, and inflammatory/autoimmune disorders.

Occult HBV among Anti-HBc Alone: Mutation Analysis of an HBV Surface Gene and Pre-S Gene.

Science.gov (United States)

Kim, Myeong Hee; Kang, So Young; Lee, Woo In

2017-05-01

The aim of this study is to investigate the molecular characteristics of occult hepatitis B virus (HBV) infection in 'anti-HBc alone' subjects. Twenty-four patients with 'anti-HBc alone' and 20 control patients diagnosed with HBV were analyzed regarding S and pre-S gene mutations. All specimens were analyzed for HBs Ag, anti-HBc, and anti-HBs. For specimens with an anti-HBc alone, quantitative analysis of HBV DNA, as well as sequencing and mutation analysis of S and pre-S genes, were performed. A total 24 were analyzed for the S gene, and 14 were analyzed for the pre-S gene through sequencing. A total of 20 control patients were analyzed for S and pre-S gene simultaneously. Nineteen point mutations of the major hydrophilic region were found in six of 24 patients. Among them, three mutations, S114T, P127S/T, M133T, were detected in common. Only one mutation was found in five subjects of the control group; this mutation was not found in the occult HBV infection group, however. Pre-S mutations were detected in 10 patients, and mutations of site aa58-aa100 were detected in 9 patients. A mutation on D114E was simultaneously detected. Although five mutations from the control group were found at the same location (aa58-aa100), no mutations of occult HBV infection were detected. The prevalence of occult HBV infection is not low among 'anti-HBc alone' subjects. Variable mutations in the S gene and pre-S gene were associated with the occurrence of occult HBV infection. Further larger scale studies are required to determine the significance of newly detected mutations. © Copyright: Yonsei University College of Medicine 2017

HBV vaccination of HCV-infected patients with occult HBV infection and anti-HBc-positive blood donors

Directory of Open Access Journals (Sweden)

J.S.F. Pereira

2006-04-01

Full Text Available Anti-HBc positivity is a frequent cause of donation rejection at blood banks. Hepatitis B virus (HBV infection may also occur in HBsAg-negative patients, a situation denoted occult infection. Similarly, very low levels of HBV-DNA have also been found in the sera of patients with chronic hepatitis C virus (HCV infection, even in the absence of serum HBsAg. Initially we searched for HBV-DNA in serum of 100 blood donors and 50 HCV-infected patients who were HBsAg negative/anti-HBc positive by nested-PCR and by an HBV monitor commercial test for HBV-DNA. Anti-HBs seroconversion rates were measured in 100 blood donors and in 22 patients with chronic HCV infection after HBV vaccination to determine if the HBV vaccination could eliminate an occult HBV infection in these individuals. Occult HBV infection was detected in proportionally fewer blood donors (6/100 = 6% than chronic hepatitis C patients (12/50 = 24% (P 0.05. All subjects who were HBV-DNA(+ before the first dose of HBV vaccine (D1, became HBV-DNA(- after D1, D2, and D3. Among 22 HCV-positive patients, 10 HBV-DNA(+ and 12 HBV-DNA(-, seroconversion was observed in 9/10 (90% HBV-DNA(+ and in 9/12 (75% HBV-DNA(- subjects (P > 0.05. The disappearance of HBV-DNA in the majority of vaccinated patients suggests that residual HBV can be eliminated in patients with occult infection.

The media of sociology: tight or loose translations?

Science.gov (United States)

Guggenheim, Michael

2015-06-01

Sociologists have increasingly come to recognize that the discipline has unduly privileged textual representations, but efforts to incorporate visual and other media are still only in their beginning. This paper develops an analysis of the ways objects of knowledge are translated into other media, in order to understand the visual practices of sociology and to point out unused possibilities. I argue that the discourse on visual sociology, by assuming that photographs are less objective than text, is based on an asymmetric media-determinism and on a misleading notion of objectivity. Instead, I suggest to analyse media with the concept of translations. I introduce several kinds of translations, most centrally the distinction between tight and loose ones. I show that many sciences, such as biology, focus on tight translations, using a variety of media and manipulating both research objects and representations. Sociology, in contrast, uses both tight and loose translations, but uses the latter only for texts. For visuals, sociology restricts itself to what I call 'the documentary': focusing on mechanical recording technologies without manipulating either the object of research or the representation. I conclude by discussing three rare examples of what is largely excluded in sociology: visual loose translations, visual tight translations based on non-mechanical recording technologies, and visual tight translations based on mechanical recording technologies that include the manipulation of both object and representation. © London School of Economics and Political Science 2015.

Detection of occult hepatitis B virus among chronic hepatitis C patients

African Journals Online (AJOL)

Background: Concurrent infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) are increasingly recognized in patients with chronic hepatitis. In Egypt, the last decade showed a remarkable decline in HBV infection associated with remarkable rise in HCV infection. The probable impact of occult HBV in patients ...

[Occult pneumothorax: Does it take drain before elective surgery?].

Science.gov (United States)

Bensghir, M; Moutaoukil, M; Meziane, M; Jaafari, A; Hemmaoui, B; Haimeur, C

2016-08-01

Pneumothorax occult is defined by the presence of a non-visible to standard asymptomatic pneumothorax and pulmonary diagnosed only by X-ray computed tomography. The presence of this type of pneumothorax before planned surgery is a rare situation. What to do remains non-consensual. Through two clinic cases and a literature review, the authors discuss the modalities of management of this entity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The prevalence of visible and/or occult blood on anesthesia and monitoring equipment.

Science.gov (United States)

Perry, S M; Monaghan, W P

2001-02-01

The Occupational Safety and Health Administration (OSHA) and the Centers for Disease Control and Prevention (CDC) have attempted to stop the spread of blood-borne pathogens by issuing several recommendations and regulations. However, unless healthcare workers comply with these standards, they are not effective. In the anesthesia care environment, the anesthetist is responsible for ensuring that the equipment is clean, and disinfected, before use. We studied the prevalence of visible and occult blood on 6 types of anesthesia and monitoring equipment identified as ready for use in 28 operating suites, in 2 facilities. The sample consisted of 336 observations of the 6 types of equipment. The equipment was inspected for visible blood and then tested for occult blood using a 3-stage phenolphthalein test. Of the 336 observations, 110 (32.7%), were positive for occult blood with only 6 showing visible blood. The presence of blood on this equipment may be in direct violation of the OSHA Blood-borne Pathogen Standard and the infection control guidelines of the American Association of Nurse Anesthetists. Furthermore, the presence of blood on this equipment may increase the risk for nosocomial and occupational exposure to viral and bacterial pathogens. Recommendations were made to decrease the risks from this contamination by redesigning equipment, increasing the use of disposable equipment, and ensuring compliance with effective infection control practices.

Astr 101 Students' Attitudes Towards Essays On Transits, Eclipses And Occultations

Science.gov (United States)

D'Cruz, Noella L.

2012-05-01

Joliet Junior College, Joliet, IL offers a one semester introductory astronomy course each semester. We teach over 110 primarily non-science major students each semester. We use proven active learning strategies such lecture tutorials, think-pair-share questions and small group discussions to help these students develop and retain a good understanding of astrophysical concepts. Occasionally, we offer projects that allow students to explore course topics beyond the classroom. We hope that such projects will increase students' interest in astronomy. We also hope that these assignments will help students to improve their critical thinking and writing skills. In Spring 12, we are offering three short individual essay assignments in our face-to-face sections. The essays focus on transits, eclipses and occultations to highlight the 2012 transit of Venus. For the first essay, students will find images of transit and occultation events using the Astronomy Picture of the Day website and describe their chosen events. In addition, students will predict how variations in certain physical and orbital parameters would alter their particular events. The second essay involves transits, eclipses and occultations observed by spacecraft. Students will describe their transit event, their spacecraft's mission, orbital path, how the orbital path was achieved, etc. The third essay deals with transiting exoplanets. Students will choose at least two exoplanets from an exoplanet database, one of which has been discovered through the transit method. This essay will enable students to learn about detecting exoplanets and how they compare with our solar system. Details of the essay assignments and students' reactions to them will be presented at the meeting.

Occultations of Astrophysical Radio Sources as Probes of Planetary Environments: A Case Study of Jupiter and Possible Applications to Exoplanets

Energy Technology Data Exchange (ETDEWEB)

Withers, Paul [Astronomy Department, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States); Vogt, Marissa F. [Center for Space Physics, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)

2017-02-10

Properties of planetary atmospheres, ionospheres, and magnetospheres are difficult to measure from Earth. Radio occultations are a common method for measuring these properties, but they traditionally rely on radio transmissions from a spacecraft near the planet. Here, we explore whether occultations of radio emissions from a distant astrophysical radio source can be used to measure magnetic field strength, plasma density, and neutral density around planets. In a theoretical case study of Jupiter, we find that significant changes in polarization angle due to Faraday rotation occur for radio signals that pass within 10 Jupiter radii of the planet and that significant changes in frequency and power occur from radio signals that pass through the neutral atmosphere. There are sufficient candidate radio sources, such as pulsars, active galactic nuclei, and masers, that occultations are likely to occur at least once per year. For pulsars, time delays in the arrival of their emitted pulses can be used to measure plasma density. Exoplanets, whose physical properties are very challenging to observe, may also occult distant astrophysical radio sources, such as their parent stars.

Profiling Saturn's rings by radio occultation

International Nuclear Information System (INIS)

Marouf, E.A.; Tyler, G.L.; Rosen, P.A.

1986-01-01

The development of reconstruction algorithms that correct for diffraction effects in radio occultation measurements is described. The reciprocal Fresnel transform relationship between the complex amplitude of the observed coherent signal and the complex microwave transmittance of the rings is derived using the Huygens-Fresnel formulation of the diffraction problem. The effects of the finite data segment width, the uncertainties in the Fresnel scale, systematic phase errors in the kernel of the inverse transform, reference oscillator instabilities, and random noise measurements on the resolution of the reconstructed transmittance are analyzed. Examples of reconstructed opacity profiles for some regions of Saturn's rings derived by applying the reconstruction theory to Voyager 1 at Saturn data are presented. 35 references

Investigation of particle sizes in Pluto's atmosphere from the 29 June 2015 occultation

Science.gov (United States)

Sickafoose, Amanda A.; Bosh, A. S.; Person, M. J.; Zuluaga, C. A.; Levine, S. E.; Pasachoff, J. M.; Babcock, B. A.; Dunham, E. W.; McLean, I.; Wolf, J.; Abe, F.; Bida, T. A.; Bright, L. P.; Brothers, T.; Christie, G.; Collins, P. L.; Durst, R. F.; Gilmore, A. C.; Hamilton, R.; Harris, H. C.; Johnson, C.; Kilmartin, P. M.; Kosiarek, M. R.; Leppik, K.; Logsdon, S.; Lucas, R.; Mathers, S.; Morley, C. J. K.; Natusch, T.; Nelson, P.; Ngan, H.; Pfüller, E.; de, H.-P.; Sallum, S.; Savage, M.; Seeger, C. H.; Siu, H.; Stockdale, C.; Suzuki, D.; Thanathibodee, T.; Tilleman, T.; Tristam, P. J.; Van Cleve, J.; Varughese, C.; Weisenbach, L. W.; Widen, E.; Wiedemann, M.

2015-11-01

The 29 June 2015 observations of a stellar occultation by Pluto, from SOFIA and ground-based sites in New Zealand, indicate that haze was present in the lower atmosphere (Bosh et al., this conference). Previously, slope changes in the occultation light curve profile of Pluto’s lower atmosphere have been attributed to haze, a steep thermal gradient, and/or a combination of the two. The most useful diagnostic for differentiating between these effects has been observing occultations over a range of wavelengths: haze scattering and absorption are functions of particle size and are wavelength dependent, whereas effects due to a temperature gradient should be largely independent of observational wavelength. The SOFIA and Mt. John data from this event exhibit obvious central flashes, from multiple telescopes observing over a range of wavelengths at each site (Person et al. and Pasachoff et al., this conference). SOFIA data include Red and Blue observations from the High-speed Imaging Photometer for Occultations (HIPO, at ~ 500 and 850 nm), First Light Infrared Test Camera (FLITECAM, at ~1800 nm), and the Focal Plan Imager (FPI+, at ~ 600 nm). Mt. John data include open filter, g', r', i', and near infrared. Here, we analyze the flux at the bottom of the light curves versus observed wavelength. We find that there is a distinct trend in flux versus wavelength, and we discuss applicable Mie scattering models for different particle size distributions and compositions (as were used to characterize haze in Pluto's lower atmosphere in Gulbis et al. 2015).SOFIA is jointly operated by the Universities Space Research Association, Inc. (USRA), under NASA contract NAS2-97001, and the Deutsches SOFIA Institut (DSI) under DLR contract 50 OK 0901 to the University of Stuttgart. Support for this work was provided by the National Research Foundation of South Africa, NASA SSO grants NNX15AJ82G (Lowell Observatory), PA NNX10AB27G (MIT), and PA NNX12AJ29G (Williams College), and the NASA

Tight fitting garter springs-MODAR

Energy Technology Data Exchange (ETDEWEB)

Kazimer, D. [Bruce Power, Tiverton, Ontario (Canada)

2011-07-01

Annulus spacers are used in CANDU reactors to maintain the annular gap between two tubes - an inner pressure tube (PT) and the outer calandria tube (CT). Typically four annulus spacers are used in one fuel channel assembly, each at a specified axial position. Bruce Unit 8 and many other CANDU units were constructed with tight-fitting garter springs (TFGS). The TFGS were not designed to be detected or relocated by the conventional tool, Spacer Location And Repositioning (SLAR) processes. Due to non-optimal 'As Left' construction locations for the Bruce Unit 8 TFGS, PT/CT contact has been predicted to occur well prior to its End of Life (EOL). Bruce Power entered a Project with AECL-CRL to design, manufacture and test and implement a new tooling system that would detect and reposition tight fitting annulus spacers. (author)

Advanced Electrocardiography Can Identify Occult Cardiomyopathy in Doberman Pinschers

Science.gov (United States)

Spiljak, M.; Petric, A. Domanjko; Wilberg, M.; Olsen, L. H.; Stepancic, A.; Schlegel, T. T.; Starc, V.

2011-01-01

Recently, multiple advanced resting electrocardiographic (A-ECG) techniques have improved the diagnostic value of short-duration ECG in detection of dilated cardiomyopathy (DCM) in humans. This study investigated whether 12-lead A-ECG recordings could accurately identify the occult phase of DCM in dogs. Short-duration (3-5 min) high-fidelity 12-lead ECG recordings were obtained from 31 privately-owned, clinically healthy Doberman Pinschers (5.4 +/- 1.7 years, 11/20 males/females). Dogs were divided into 2 groups: 1) 19 healthy dogs with normal echocardiographic M-mode measurements: left ventricular internal diameter in diastole (LVIDd . 47mm) and in systole (LVIDs . 38mm) and normal 24-hour ECG recordings (100 VPCs/24h; 1/12 dogs had only abnormal 24-hour ECG recordings (>100 VPCs/24h). ECG recordings were evaluated via custom software programs to calculate multiple parameters of high-frequency (HF) QRS ECG, heart rate variability, QT variability, waveform complexity and 3-D ECG. Student's t-tests determined 19 ECG parameters that were significantly different (P canine DCM as five selected ECG parameters can with reasonable accuracy identify occult DCM in Doberman Pinschers. Future extensive clinical studies need to clarify if 12-lead A-ECG could be useful as an additional screening test for canine DCM.

Atmospheric deposition of heavy metals due to dry, wet and occult deposition at the altitude profile Achenkirch

International Nuclear Information System (INIS)

Stopper, S.

2001-12-01

The goal of this work was to determine the height dependence of the three types of deposition throughout a one year time period to be able to get information about their elevational and seasonal behavior. In the time period from October 1998 to November 1999 measurements of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn in aerosol, rain and cloud water were conducted in the Achenkirch-Valley in Tyrol, Austria. Afterwards the dry and occult deposition were modeled. The estimated annual inputs of metals at the two measurement sites Christlumkopf (1758 m a.s.l.) Mueeggerkoel (940 m a.s.l.) and the limits of the national law for protection of forest are shown. The measured depositions at both sites were far below the legal regulations. Due to the much higher occult deposition ratio at the top of the mountain the total annual input at the Christlumkopf was higher than at the Mueeggerkoel. This indicates the potential importance of occult deposition. (author)

Three-dimensional measurement of a tightly focused laser beam

Directory of Open Access Journals (Sweden)

Xiangsheng Xie

2013-02-01

Full Text Available The spatial structure of a tightly focused light field is measured with a double knife-edge scanning method. The measurement method is based on the use of a high-quality double knife-edge fabricated from a right-angled silicon fragment mounted on a photodetector. The reconstruction of the three-dimensional structures of tightly focused spots is carried out with both uniform and partially obstructed linearly polarized incident light beams. The optical field distribution is found to deviate substantially from the input beam profile in the tightly focused region, which is in good agreement with the results of numerical simulations.

Metastatic Squamous Neck Cancer with Occult Primary Treatment (PDQ®)—Health Professional Version

Science.gov (United States)

Metastatic squamous neck cancer with occult primary treatment options include surgery, radiation therapy or a combination of both. Get detailed information about newly diagnosed or recurrent metastatic squamous neck cancer in this summary for clinicians.

Western tight gas sands advanced logging workshop proceedings

Energy Technology Data Exchange (ETDEWEB)

Jennings, J B; Carroll, Jr, H B [eds.

1982-04-01

An advanced logging research program is one major aspect of the Western Tight Sands Program. Purpose of this workshop is to help BETC define critical logging needs for tight gas sands and to allow free interchange of ideas on all aspects of the current logging research program. Sixteen papers and abstracts are included together with discussions. Separate abstracts have been prepared for the 12 papers. (DLC)

Significance of mammographic signs in clinically occult disease

Energy Technology Data Exchange (ETDEWEB)

Waal, J.C. de; Steil, B.; Baltzer, J.; Vaillant, W.; Zander, J.

1987-10-01

The significance of various radiographic signs in 183 patients with clinically occult breast disease is described. 30.6% hat a carcinoma of the breast or a carcinoma in situ. The radiological features have varying predictive values and there is variation in the incidence of lymph node metastases. It is considered useful to classify the radiological appearances under the headings of round foci, star-shaped opacities, diffuse opacities, opacities with calcification and groups of micro-calcification. Despite the early diagnosis, 24% of patients already had lymph node metastases.

Ultrasound Diagnosis of Either an Occult or Missed Fracture of an Extremity in Pediatric-Aged Children

Energy Technology Data Exchange (ETDEWEB)

Cho, Kil Ho [Yeungnam University, Daegu (Korea, Republic of); Lee, Sung Moon [Keimyung University Dongsan Hospital, Daegu (Korea, Republic of); Lee, Young Hwan [Daegu Catholic University, Daegu (Korea, Republic of); Suh, Kyung Jin [Dongkuk University, Kyungju (Korea, Republic of)

2010-02-15

To report and assess the usefulness of ultrasound (US) findings for occult fractures of growing bones. For six years, US scans were performed in children younger than 15 years who were referred with trauma-related local pain and swelling of the extremities. As a routine US examination, the soft tissue, bones, and adjacent joints were examined in the area of discomfort, in addition to the asymptomatic contralateral extremity for comparison. Twenty-five occult fractures in 25 children (age range, five months-15 years; average age, 7.7 years) were confirmed by initial and follow-up radiograms, additional imaging studies, and clinical observation longer than three weeks. The most common site of occult fractures was the elbow (n = 9, 36%), followed by the knee (n = 7, 28%), ischium (n = 4, 16%), distal fibula (n = 3, 12%), proximal femur (n = 1, 4%), and humeral shaft (n = 1, 4%). On the retrograde review of the routine radiographs, 13 out of the 25 cases showed no bone abnormalities except for various soft tissue swelling. For the US findings, cortical discontinuity (direct sign of a fracture) was clearly visualized in 23 cases (92%) and was questionable in two (8%). As auxiliary US findings (indirect signs of a fracture), step-off deformities, tiny avulsed bone fragments, double-line appearance of cortical margins, and diffuse irregularity of the bone surfaces were identified. Performing US for soft tissue and bone surfaces with pain and swelling, with or without trauma history in the extremities, is important for diagnosing occult or missed fractures of immature bones in pediatric-aged children.

Earlier stages of colorectal cancer detected with immunochemical faecal occult blood tests

NARCIS (Netherlands)

van Rossum, L. G. M.; van Rijn, A. F.; van Munster, I. P.; Jansen, J. B. M. J.; Fockens, P.; Laheij, R. J. F.; Dekker, E.

2009-01-01

Background: The aim of colorectal cancer screening is to improve prognosis by the detection of early cancer and precursor stages. We compared the stage distribution of asymptomatic colorectal cancer patients detected by a positive immunochemical or guaiac-based faecal occult blood test (FOBT) with

Imaging of congenital anomalies and variations of the caudal spine and back in neonates and small infants

Energy Technology Data Exchange (ETDEWEB)

Schenk, Jens-Peter [Department of Pediatric Radiology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany)]. E-mail: Jens-Peter_Schenk@med.uni-heidelberg.de; Herweh, Christian [Department of Pediatric Radiology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany); Department of Neuroradiology, University of Heidelberg (Germany); Guenther, Patrick [Department of Pediatric Surgery, University of Heidelberg (Germany); Rohrschneider, Wiltrud [Department of Pediatric Radiology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany); Zieger, Birgit [Department of Pediatric Radiology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany); Troeger, Jochen [Department of Pediatric Radiology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany)

2006-04-15

Spinal dysraphisms are categorized in open dysraphisms with prominent abnormal nervous tissue above the skinlevel and closed dysraphisms with a skin covered malformation. Especially the occult dysraphisms are marked by suspect skin masses and other dermal anomalies. The purpose of this review is to demonstrate the indications and spectrum of spinal sonography in neonates and infants. In comparison typical dysraphisms are demonstrated in sonography and MR Imaging. We demonstrate the value of ultrasound in comparison to MRI and describe a useful handling of the methods in neonates and infants. The differentiation between the potentially dangerous dimples associated with dermal sinus, which can lead to meningitis and the harmless coccygeal dimple in the cranial gluteal cleft is presented. An inconspicious examination does not need a further imaging, but suspicious results of sonography need an MR imaging dependent of clinical conditions. Neurologically conspicious infants need MR imaging completed by sonography. Great advantages of sonography are the real time examination and the potential to show oscillations of the conus, filum and cauda equina in M-mode-imaging.

PREVALENCE OF OCCULT DEPRESSION IN ELDERLY WITH CHRONIC CO - MORBIDS

Directory of Open Access Journals (Sweden)

Sachin

2015-02-01

Full Text Available BACKGROUND: Growth in elderly population has led to an increase in age related diseases and mainly depression which is affecting the quality of life. Depression is more prevalent amongst elderly individuals with medical illnesses and emerging public health problem leading to increased morbidity and disability worldwide. AIMS AND OBJE CTIVES: To assess the prevalence of occult depression in elderly patients with chronic co - morbid medical conditions. MATERIALS AND METHODS: It was a cross - sectional study conducted in tertiary hospital. Total 100 elderly patients with underlying chronic me dical illnesses were included. Depression in study population was assessed by geriatric depression scale and analyzed. RESULT: Out of 100 patients 23(23% had depression. Females 12/39(30.76% were affected more than males 11/61 (18.03%. Depression was mo re prevalent among patients with 3 or more co - morbid conditions (45.4% as compared to <3 (11.9%. CONCLUSION: Elderly patients with multiple chronic medical illnesses may have associated occult depression. Screening of these patients for depression couple d with appropriate psychiatric referral should be an integral part of Geriatric service

Waves in the Martian Atmosphere: Results from MGS Radio Occultations

Science.gov (United States)

Flasar, F. M.; Hinson, D. P.; Tyler, G. L.

1999-01-01

Temperatures retrieved from Mars Global Surveyor radio occultations have been searched for evidence of waves. Emphasis has been on the initial series of occultations between 29 deg N and 64 deg S, obtained during the early martian southern summer, L(sub s) = 264 deg - 308 deg. The profiles exhibit an undulatory behavior that is suggestive of vertically propagating waves. wavelengths approximately 10 km are often dominant, but structure on smaller scales is evident. The undulatory structure is most pronounced between latitudes 29 deg N and 10 deg S, usually in regions of "interesting" topography, e.g., in the Tharsis region and near the edge of Syrtis Major. Several temperature profiles, particularly within 30 deg of the equator, exhibit lapse rates that locally become superadiabatic near the 0.4-mbar level or at higher altitudes. This implies that the waves are "breaking" and depositing horizontal momentum into the atmosphere. Such a deposition may play an important role in modulating the atmospheric winds, and characterizing the spatial and temporal distribution of these momentum transfers can provide important clues to understanding how the global circulation is maintained.

Comparative testing of women's tights, which are realized in the Ukrainian market

OpenAIRE

Мартосенко, Марина Григорьевна; Браилко, Анна Сергеевна

2015-01-01

Assortment of women's tights represented on the Ukrainian market is diverse: medical and corrective tights, classic thin and warm, simple and exclusive, ornamental and sports, for pregnant women and moisturizing effect. The size, density, pattern, material composition, visual appearance, matching fashion trends, colors, pricing policy – all these are criteria for the selection of women's tights.With such huge and diverse range of women's tights in the Ukrainian market, the problem of quality ...

Ionospheric Remote Sensing using GPS Radio Occultation and Ultraviolet Photometry aboard the ISS

Science.gov (United States)

Budzien, S. A.; Powell, S. P.; O'Hanlon, B.; Humphreys, T.; Bishop, R. L.; Stephan, A. W.; Gross, J.; Chakrabarti, S.

2017-12-01

The GPS Radio Occultation and Ultraviolet Photometer Co-located (GROUP-C) experiment launched to the International Space Station (ISS) on February 19, 2017 as part of the Space Test Program Houston #5 payload (STP-H5). After early orbit testing, GROUP-C began routine science operations in late April. GROUP-C includes a high-sensitivity far-ultraviolet photometer measuring horizontal nighttime ionospheric gradients and an advanced software-defined GPS receiver providing ionospheric electron density profiles, scintillation measurements, and lower atmosphere profiles. GROUP-C and a companion experiment, the Limb-Imaging Ionospheric and Thermospheric Extreme-Ultraviolet Spectrograph (LITES), offer a unique capability to study spatial and temporal variability of the thermosphere and ionosphere using multi-sensor approaches, including ionospheric tomography. Data are collected continuously across low- and mid-latitudes as the ISS orbit precesses through all local times every 60 days. The GROUP-C GPS sensor routinely collects dual-frequency GPS occultations, makes targeted raw signal captures of GPS and Galileo occultations, and includes multiple antennas to characterize multipath in the ISS environment. The UV photometer measures the 135.6 nm ionospheric recombination airglow emision along the nightside orbital track. We present the first analysis of ionospheric observations, discuss the challenges and opportunities of remote sensing from the ISS platform, and explore how these new data help address questions regarding the complex and dynamic features of the low and middle latitude ionosphere-thermosphere relevant to the upcoming GOLD and ICON missions.

Usefullness of routine use of fecal occult blood test in a hospital setting

Directory of Open Access Journals (Sweden)

Simona Ravnik

2006-12-01

Full Text Available Background: Fecal occult blood test, hematest, is a well excepted non-invasive method used for detecting different diseases of the gastrointestinal tract. It was proven in different randomized studies that usage of this simple method may facilitate further diagnostic and therapeutic treatment.Patients and methods: The retrospective analysis includes patients, which were admitted to the gastroenterological and endoscopy department of the General hospital Maribor in the last quarter of the year 2005. In all patients fecal occult blood test was performed.Results: We examined 200 patients, 104 women and 96 men, average age 63.9 years, SD±16.9, ranging from 21 to 97 years. Positive hematest was discovered in 76 patients (38 %. The source of hemorrhage from the upper digestive tract was confirmed in 37 patients (48.6 % of all positive tests and from the lower digestive tract in 34 patients (46 % of all positive tests. The most frequent causes of hemorrhage from the lower digestive tract were chronic inflammatory bowel disease (13.1 % of all positive tests, colorectal cancer (10.5 % and polyps (6.6 %. The source of hemorrhage was not located in five patients (6.6 % of all positive tests despite the accurate diagnostic procedure.Conclusions: By performing a fecal occult blood screening in non-symptomatic patients, we can make an essential step towards discovering different gastrointestinal diseases, even colorectal cancer in its early, limited form, when the effect of treatment is greatest.

Final binary star results from the ESO VLT Lunar occultations program

Energy Technology Data Exchange (ETDEWEB)

Richichi, A. [National Astronomical Research Institute of Thailand, 191 Siriphanich Bldg., Huay Kaew Road, Suthep, Muang, Chiang Mai 50200 (Thailand); Fors, O. [Departament Astronomia i Meteorologia and Institut de Ciències del Cosmos (ICC), Universitat de Barcelona (UB/IEEC), Martí i Franqués 1, E-08028 Barcelona (Spain); Cusano, F. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Ivanov, V. D., E-mail: andrea4work@gmail.com [European Southern Observatory, Ave. Alonso de Cordova 3107, Casilla 19001, Santiago 19 (Chile)

2014-03-01

We report on 13 subarcsecond binaries, detected by means of lunar occultations in the near-infrared at the ESO Very Large Telescope (VLT). They are all first-time detections except for the visual binary HD 158122, which we resolved for the first time in the near-infrared. The primaries have magnitudes in the range K = 4.5-10.0, and companions in the range K = 6.8-11.1. The magnitude differences have a median value of 2.4, with the largest being 4.6. The projected separations are in the range of 4-168 mas, with a median of 13 mas. We discuss and compare our results with the available literature. With this paper, we conclude the mining for binary star detections in the 1226 occultations recorded at the VLT with the ISAAC instrument. We expect that the majority of these binaries may be unresolvable by adaptive optics on current telescopes, and they might be challenging for long-baseline interferometry. However, they constitute an interesting sample for future larger telescopes and for astrometric missions such as GAIA.

Lunar occultation of Saturn. II - The normal reflectance of Rhea, Titan, and Iapetus

Science.gov (United States)

Elliot, J. L.; Dunham, E. W.; Veverka, J.; Goguen, J.

1978-01-01

An inversion procedure to obtain the reflectance of the central region of a satellite's disk from lunar occultation data is presented. The scheme assumes that the limb darkening of the satellite depends only on the radial distance from the center of the disk. Given this assumption, normal reflectances can be derived that are essentially independent of the limb darkening and the diameter of the satellite. The procedure has been applied to our observations of the March 1974 lunar occultation of Tethys, Dione, Rhea, Titan, and Iapetus. In the V passband we derive the following normal reflectances: Rhea (0.97 plus or minus 0.20), Titan (0.24 plus or minus 0.03), Iapetus, bright face (0.60 plus or minus 0.14). For Tethys and Dione the values derived have large uncertainties, but are consistent with our result for Rhea.

Air tightness measurements in older Danish single-family houses

DEFF Research Database (Denmark)

Mortensen, Lone Hedegaard; Bergsøe, Niels Christian

2017-01-01

of the building envelope of older buildings despite the fact that the air tightness has a major influence on the energy use. In connection with renovation of the Danish building stock, the coming years will see increased focus on the air tightness of the building envelope like in other countries. This paper...

Occult Radiographically Evident Port-Site Hernia After Robot-Assisted Urologic Surgery: Incidence and Risk Factors.

Science.gov (United States)

Christie, Matthew C; Manger, Jules P; Khiyami, Abdulaziz M; Ornan, Afshan A; Wheeler, Karen M; Schenkman, Noah S

2016-01-01

Laparoscopic trocar-site hernias (TSH) are rare, with a reported incidence of 1% or less. The incidence of occult radiographically evident hernias has not been described after robot-assisted urologic surgery. We evaluated the incidence and risk factors of this problem. A single-institution retrospective review of robot-assisted urologic surgery was performed from April 2009 to December 2012. Patients with preoperative and postoperative CT were included for analysis. Imaging was reviewed by two radiologists and one urologist. One hundred four cases were identified, including 60 partial nephrectomy, 38 prostatectomy, and 6 cystectomy. Mean age was 58 years and mean body mass index (BMI) was 29 kg/m(2). The cohort was 77% male. Ten total hernias were identified by CT in 8 patients, 2 of which were clinically evident hernias. Excluding these two hernias, occult port-site hernias were identified radiographically in seven patients. Per-patient incidence of occult TSH was 6.7% (7/104), and per-port incidence was 1.4% (8/564). All hernias were midline and 30% contained bowel. Eight of the 10 occurred at 12 mm sites (p = 0.0065) and 3 of the 10 occurred at extended incisions. Age, gender, BMI, smoking status, diabetes mellitus, immunosuppressive drug therapy, ASA score, procedure, blood loss, prior abdominal surgery, and history of hernia were not significant risk factors. Specimen size >40 g (p = 0.024) and wound infection (p = 0.0052) were significant risk factors. While the incidence of clinically evident port-site hernia remains low in robot-assisted urologic surgery, the incidence of CT-detected occult hernia was 6.7% in this series. These occurred most often in sites extended for specimen extraction and at larger port sites. This suggests more attention should be paid to fascial closure at these sites.

Efficacy of benazepril hydrochloride to delay the progression of occult dilated cardiomyopathy in Doberman Pinschers.

Science.gov (United States)

O'Grady, M R; O'Sullivan, M L; Minors, S L; Horne, R

2009-01-01

Angiotensin converting enzyme inhibitors (ACEIs) are recommended in people to treat asymptomatic (occult) dilated cardiomyopathy (DCM). Efficacy of therapy in occult DCM in dogs is unknown. ACEIs, specifically benazepril hydrochloride (BH), will delay the onset of overt DCM in Doberman Pinschers. Ninety-one Doberman Pinschers were studied, 57 dogs received BH, and 34 dogs no ACEI. Retrospective study of the medical records of all Doberman Pinschers with occult DCM that received BH or no ACEI between April 1989 and February 2003. Two criteria of left ventricular enlargement were used for enrollment: one independent of body weight (BW) (C1) and the other indexed to BW (C2). Cox proportional hazards analyses were used to identify variables associated with the onset of overt DCM. On univariate analysis the median time to onset of overt DCM was significantly longer for the benazepril group (for C1: 425 days for BH, 95% confidence interval [CI] 264-625 days; 339 days for no ACEI, CI 172-453 days, P= .02; for C2: 454 days for BH, CI 264-628 days; 356 days for no ACEI, CI 181-547 days, P= .02). The hazard ratio (HR) (benazepril/no ACEI) was 0.57, CI 0.35-0.94, P= .03 for C1; HR = 0.56, CI 0.34-0.93, P= .02 for C2. On multivariate analysis, BH significantly delayed onset of overt DCM (HR [benazepril/no ACEI] = 0.45, CI 0.26-0.78, P < .01, for C1; HR = 0.36, CI 0.21-0.63, P < .01, for C2). BH in particular and ACEIs in general might delay the progression of occult DCM. Prospective studies are warranted to test this theory.

Hamstring tightness and Scheuermann's disease a pilot study.

Science.gov (United States)

Fisk, J W; Baigent, M L

1981-06-01

The lateral radiographs of the dorsal spines of 20 patients presenting with mainly low back pain are studied. These patients had clinically evident loss of flexion in the low dorsal spine and very tight hamstring muscles. 85% of them showed definite evidence of previous Scheuermann's Disease. The possibility that tight hamstrings may be an important factor in the aetiology of this disease is discussed, and a further large scale study is proposed.

Influence of Ionospheric Weather on GNSS Radio Occultation Signals

Science.gov (United States)

Yue, X.; Schreiner, W. S.; Pedatella, N. M.; Kuo, Y. H.

2016-12-01

Transient loss of lock (LOL) is one of the key space weather effects on the Global Navigation Satellite System (GNSS). Based on the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Global Positioning System (GPS) radio occultation (RO) observations during 2007-2011, we have analyzed the signal cycle slip (CS) occurrence comprehensively and its correlation to the ionospheric weather phenomena such as sporadic E (Es), equatorial F region irregularity (EFI), and the ionospheric equatorial ionization anomaly (EIA). The high vertical resolution of RO observations enables us to distinguish the CS resulting from different ionospheric layers clearly on a global scale. In the E layer, the CS is dominated by the Es occurrence, while in the F layer, the CS is mainly related to the EIA and EFI at low and equatorial latitudes. In the polar region, the CS is primarily related to polar cap electron density gradients. The overall average CS (> 6 cycles) occurrence is 23% per occultation, with the E (50-150 km) and F (150-600 km) layers contributing 8.3% and 14.7%, respectively. Awareness of the effect of the ionospheric weather on the CS of the low-Earth-orbit (LEO)-based GNSS signal could be beneficial to a variety of applications, including the LEO-based GNSS data processing and the corresponding hardware/firmware design.

The effect of solar radio bursts on the GNSS radio occultation signals

Science.gov (United States)

Yue, Xinan; Schreiner, William S.; Kuo, Ying-Hwa; Zhao, Biqiang; Wan, Weixing; Ren, Zhipeng; Liu, Libo; Wei, Yong; Lei, Jiuhou; Solomon, Stan; Rocken, Christian

2013-09-01

radio burst (SRB) is the radio wave emission after a solar flare, covering a broad frequency range, originated from the Sun's atmosphere. During the SRB occurrence, some specific frequency radio wave could interfere with the Global Navigation Satellite System (GNSS) signals and therefore disturb the received signals. In this study, the low Earth orbit- (LEO-) based high-resolution GNSS radio occultation (RO) signals from multiple satellites (COSMIC, CHAMP, GRACE, SAC-C, Metop-A, and TerraSAR-X) processed in University Corporation for Atmospheric Research (UCAR) were first used to evaluate the effect of SRB on the RO technique. The radio solar telescope network (RSTN) observed radio flux was used to represent SRB occurrence. An extreme case during 6 December 2006 and statistical analysis during April 2006 to September 2012 were studied. The LEO RO signals show frequent loss of lock (LOL), simultaneous decrease on L1 and L2 signal-to-noise ratio (SNR) globally during daytime, small-scale perturbations of SNR, and decreased successful retrieval percentage (SRP) for both ionospheric and atmospheric occultations during SRB occurrence. A potential harmonic band interference was identified. Either decreased data volume or data quality will influence weather prediction, climate study, and space weather monitoring by using RO data during SRB time. Statistically, the SRP of ionospheric and atmospheric occultation retrieval shows ~4% and ~13% decrease, respectively, while the SNR of L1 and L2 show ~5.7% and ~11.7% decrease, respectively. A threshold value of ~1807 SFU of 1415 MHz frequency, which can result in observable GNSS SNR decrease, was derived based on our statistical analysis.

Occult progression by Apc-deficient intestinal crypts as a target for chemoprevention

Science.gov (United States)

Liskay, R.Michael

2014-01-01

Although Apc mutation is widely considered an initiating event in colorectal cancer, little is known about the earliest stages of tumorigenesis following sporadic Apc loss. Therefore, we have utilized a novel mouse model that facilitates the sporadic inactivation of Apc via frameshift reversion of Cre in single, isolated cells and subsequently tracks the fates of Apc-deficient intestinal cells. Our results suggest that consistent with Apc being a ‘gatekeeper’, loss of Apc early in life during intestinal growth leads to adenomas or increased crypt fission, manifested by fields of mutant but otherwise normal-appearing crypts. In contrast, Apc loss occurring later in life has minimal consequences, with mutant crypts being less prone to either increased crypt fission or adenoma formation. Using the stem cell-specific Lgr5-CreER mouse, we generated different sized fields of Apc-deficient crypts via independent recombination events and found that field size correlates with progression to adenoma. To evaluate this early stage prior to adenoma formation as a therapeutic target, we examined the chemopreventive effects of sulindac on Apc-deficient occult crypt fission. We found that sulindac treatment started early in life inhibits the morphologically occult spread of Apc-deficient crypts and thus reduces adenoma numbers. Taken together these results suggest that: (i) earlier Apc loss promotes increased crypt fission, (ii) a field of Apc-deficient crypts, which can form via occult crypt fission or independent neighboring events, is an important intermediate between loss of Apc and adenoma formation and (iii) normal-appearing Apc-deficient crypts are potential unappreciated targets for cancer screening and chemoprevention. PMID:23996931

Radioguided breast surgery for occult lesion localization – correlation between two methods

Directory of Open Access Journals (Sweden)

Gutfilen Bianca

2008-08-01

Full Text Available Abstract Background The detection of sub-clinical breast lesions has increased with screening mammography. Biopsy techniques can offer precision and agility in its execution, as well as patient comfort. This trial compares radioguided occult lesion localization (ROLL and wire-guided localization (WL of breast lesions. We investigate if a procedure at the ambulatorial level (ROLL could lead to a better aesthetic result and less postoperative pain. In addition, we intend to demonstrate the efficacy of radioguided localization and removal of occult breast lesions using radiopharmaceuticals injected directly into the lesions and correlate radiological and histopathological findings. Methods One hundred and twenty patients were randomized into two groups (59 WL and 61 ROLL. The patients were requested to score the cosmetic appearance of their breast after surgery, and a numerical rating scale was used to measure pain on the first postoperative day. Clearance margins were considered at ≥ 10 mm for invasive cancer, ≥ 5 mm for ductal carcinoma in situ, and ≥ 1 mm for benign disease. Patients were subsequently treated according to the definitive histological result. When appropriate, different statistical tests were used in order to test the significance between the two groups, considering a P value Results WL and ROLL located all the occult breast lesions successfully. In the ROLL group, the specimen volume was smaller and there were more cases with clear margins (P Conclusion ROLL is an effective method for the excision of non-palpable breast lesions. It enables more careful planning of the cutaneous incision, leading to better aesthetic results, less postoperative symptoms, and smaller volumes of excised tissue.

Atmospheric gravity wave detection following the 2011 Tohoku earthquakes combining COSMIC occultation and GPS observations

Science.gov (United States)

Yan, X.; Tao, Y.; Xia, C.; Qi, Y.; Zuo, X.

2017-12-01

Several studies have reported the earthquake-induced atmospheric gravity waves detected by some new technologies such as airglow (Makela et al., 2011), GOCE (Garcia et al., 2013), GRACE (Yang et al., 2014), F3/C radio occultation sounding (Coïsson et al., 2015). In this work, we collected all occultation events on 11 March, and selected four events to analyze at last. The original and filtered podTEC is represented as function of the altitude of the impact parameter and UT of the four events. Then, the travel time diagrams of filtered podTEC derived from the events were analyzed. The occultation signal from one event (marked as No.73) is consistent with the previous results reported by Coïsson. 2015, which is corresponds to the ionospheric signal induced from tsunami gravity wave. What is noticeable, in this work, is that three occultation events of No.403, 77 and 118 revealed a disturbance of atmospheric gravity wave with velocity 300m/s, preceding the tsunami. It would probably be correspond to the gravity waves caused by seismic rupture but not tsunami. In addition, it can be seen that the perturbation height of occultation observation TEC is concentrated at 200-400km, corresponding ionosphere F region. The signals detected above are compared with GPS measurements of TEC from GEONET and IGS. From GPS data, traveling ionospheric disturbances were observed spreading out from the epicenter as a quasi-circular propagation pattern with the time. Exactly, we observed an acoustic wave coupled with Rayleigh wave starting from the epicenter with a speed of 3.0km/s and a superimposed acoustic-gravity wave moving with a speed of 800m/s. The acoustic-gravity wave generated at the epicenter and gradually attenuated 800km away, then it is replaced by a gravity wave coupled with the tsunami that moves with a speed of between 100 and 300m/s. It is necessary to confirm the propagation process of the waves if we attempt to evaluate the use of ionospheric seismology as a

Unconventional Tight Reservoirs Characterization with Nuclear Magnetic Resonance

Science.gov (United States)

Santiago, C. J. S.; Solatpour, R.; Kantzas, A.

2017-12-01

The increase in tight reservoir exploitation projects causes producing many papers each year on new, modern, and modified methods and techniques on estimating characteristics of these reservoirs. The most ambiguous of all basic reservoir property estimations deals with permeability. One of the logging methods that is advertised to predict permeability but is always met by skepticism is Nuclear Magnetic Resonance (NMR). The ability of NMR to differentiate between bound and movable fluids and providing porosity increased the capability of NMR as a permeability prediction technique. This leads to a multitude of publications and the motivation of a review paper on this subject by Babadagli et al. (2002). The first part of this presentation is dedicated to an extensive review of the existing correlation models for NMR based estimates of tight reservoir permeability to update this topic. On the second part, the collected literature information is used to analyze new experimental data. The data are collected from tight reservoirs from Canada, the Middle East, and China. A case study is created to apply NMR measurement in the prediction of reservoir characterization parameters such as porosity, permeability, cut-offs, irreducible saturations etc. Moreover, permeability correlations are utilized to predict permeability. NMR experiments were conducted on water saturated cores. NMR T2 relaxation times were measured. NMR porosity, the geometric mean relaxation time (T2gm), Irreducible Bulk Volume (BVI), and Movable Bulk Volume (BVM) were calculated. The correlation coefficients were computed based on multiple regression analysis. Results are cross plots of NMR permeability versus the independently measured Klinkenberg corrected permeability. More complicated equations are discussed. Error analysis of models is presented and compared. This presentation is beneficial in understanding existing tight reservoir permeability models. The results can be used as a guide for choosing

A variational regularization of Abel transform for GPS radio occultation

OpenAIRE

T.-K. Wee

2018-01-01

In the Global Positioning System (GPS) radio occultation (RO) technique, the inverse Abel transform of measured bending angle (Abel inversion, hereafter AI) is the standard means of deriving the refractivity. While concise and straightforward to apply, the AI accumulates and propagates the measurement error downward. The measurement error propagation is detrimental to the refractivity in lower altitudes. In particular, it builds up negative refractivity bias in the tropical ...

Sonographic swelling of pronator quadratus muscle in patients with occult bone injury

International Nuclear Information System (INIS)

Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo; Toyabe, Shin-ichi

2015-01-01

The disarranged fat stripe of the pronator quadratus muscle (PQ) on radiographs (the PQ sign) is reported to be predictive of subtle bone fractures. This study aimed to report the results of magnetic resonance imaging (MRI) study in the patients in whom bone injury was not radiographically detected around the wrist joint, and the PQ was sonographically swollen following acute trauma. We evaluated sonographically the PQ of 55 patients who showed normal radiographs following acute trauma. The sonographic appearance of the PQ was checked on both longitudinal and transverse images. On the longitudinal image, the probe was positioned along the flexor carpi radialis tendon. For the transverse image, we adopted the image of the same level in which the PQ of the unaffected hand showed maximal thickness. The PQ was considered to be swollen with disproportionate hyperechogenicity and/or thickening compared with the unaffected side at least in one of the two images. Of the 55 patients, 25 patients whose PQ was considered to be swollen underwent MRI study. PQ thickness in millimeters was retrospectively measured on longitudinal and transverse sonographic images. Twenty-three patients (92.0%) had occult bone injury, and two adult patients (8.0%) showed only wrist joint effusion on MRI. Among these 23, the distal radius was the most frequent location of the occult bone injury (20 patients; 9 [36.0%] with an occult fracture line and 11 [44.0%] with bone bruising). In longitudinal image, the mean value of the PQ thickness of affected hands was 6.2 (3.7–9.6 mm; standard deviation [SD], 1.5) and that of unaffected hands was 4.5 (2.3–6.7 mm; SD, 1.2), respectively. In transverse image, that of dominant and nondominant hands was 7.6 (4.6–13.2 mm; SD, 2.0) and 5.5 (3.6–7.5 mm; SD, 1.1), respectively. The mean difference in PQ thickness between affected and unaffected hands was 1.7 (0.1–5.0 mm; SD, 1.1) in longitudinal image and 2.0 (0.3–6.8 mm; SD, 1.7) in transverse image

Fluctuations of radio occultation signals in sounding the Earth's atmosphere

Directory of Open Access Journals (Sweden)

V. Kan

2018-02-01

Full Text Available We discuss the relationships that link the observed fluctuation spectra of the amplitude and phase of signals used for the radio occultation sounding of the Earth's atmosphere, with the spectra of atmospheric inhomogeneities. Our analysis employs the approximation of the phase screen and of weak fluctuations. We make our estimates for the following characteristic inhomogeneity types: (1 the isotropic Kolmogorov turbulence and (2 the anisotropic saturated internal gravity waves. We obtain the expressions for the variances of the amplitude and phase fluctuations of radio occultation signals as well as their estimates for the typical parameters of inhomogeneity models. From the GPS/MET observations, we evaluate the spectra of the amplitude and phase fluctuations in the altitude interval from 4 to 25 km in the middle and polar latitudes. As indicated by theoretical and experimental estimates, the main contribution into the radio signal fluctuations comes from the internal gravity waves. The influence of the Kolmogorov turbulence is negligible. We derive simple relationships that link the parameters of internal gravity waves and the statistical characteristics of the radio signal fluctuations. These results may serve as the basis for the global monitoring of the wave activity in the stratosphere and upper troposphere.

Prevalence, risk factors, and impact of isolated antibody to hepatitis B core antigen and occult hepatitis B virus infection in HIV-1-infected pregnant women.

Science.gov (United States)

Khamduang, Woottichai; Ngo-Giang-Huong, Nicole; Gaudy-Graffin, Catherine; Jourdain, Gonzague; Suwankornsakul, Weerapong; Jarupanich, Tapnarong; Chalermpolprapa, Veeradate; Nanta, Sirisak; Puarattana-Aroonkorn, Noossara; Tonmat, Sakchai; Lallemant, Marc; Goudeau, Alain; Sirirungsi, Wasna

2013-06-01

Prevalence and risk factors for isolated antibody to hepatitis B core antigen (anti-HBc) and occult hepatitis B virus (HBV) infection are not well known in human immunodeficiency virus type 1 (HIV-1)-infected pregnant women. It is unclear if women with occult infections are at risk of transmitting HBV to their infants. HIV-1-infected and HBV surface antigen (HBsAg)-negative pregnant women were tested for antibody to HBsAg (anti-HBs) and anti-HBc using enzyme immunoassay. Women with isolated anti-HBc were assessed for occult HBV infection, defined as HBV DNA levels >15 IU/mL, using the Abbott RealTime HBV DNA assay. Infants born to women with isolated anti-HBc and detectable HBV DNA were tested at 4 months of age for HBV DNA. Logistic regression analysis was used to identify factors associated with isolated anti-HBc and occult HBV infection. Among 1812 HIV-infected pregnant women, 1682 were HBsAg negative. Fourteen percent (95% confidence interval [CI], 12%-15%) of HBsAg-negative women had an isolated anti-HBc that was independently associated with low CD4 count, age >35 years, birth in northern Thailand, and positive anti-hepatitis C virus serology. Occult HBV infection was identified in 24% (95% CI, 18%-30%) of women with isolated anti-HBc, representing 2.6% (95% CI, 1.9%-3.5%) of HIV-1-infected pregnant women, and was inversely associated with HIV RNA levels. None of the women with isolated anti-HBc and occult HBV infection transmitted HBV to their infants. HIV-1-infected pregnant women with isolated anti-HBc and occult HBV infection have very low HBV DNA levels and are thus at very low risk to transmit HBV to their infants.

Combined parathyroid adenoma and an occult papillary carcinoma

International Nuclear Information System (INIS)

Meshikhes, Abdul-Wahid N.; Al-Saihati, Basima A.; Butt, Mohammad S.

2004-01-01

Although the pathological association of thyroid and parathyroid disease is common, the association of both parathyroid adenoma and thyroid cancer is rare. We report here a case of a 45-year-old saudi women who diagnosed to have primary hyperparathyrodism due to single parathyroid adenoma as confirmed biochemically and radiologically. At operation, the adenoma was found to be an intrathyroid and therefore a thyroid lobectomy was performed. Histology of the excised lobe revealed in addition to the intrathyroid parathyroid adenoma a concurrent occult thyroid papillary carcinoma. The interesting association is discussed based on a literature review. (author)

MR imaging of occult fractures of the knee

International Nuclear Information System (INIS)

Mink, J.H.; Deutsch, A.L.

1988-01-01

The authors encountered 65 radiographically occult fractures that they classified into five types. Bone bruises were a result of direct trauma or were associated with ligamentous injury. They were characterized by geographic foci of decreased signal on short repetition time (TR), short echo time (TE) sequences. Stress fractures were linear or globular foci of low signal on short TR, short TE sequences. Osteochondral fractures were displaced or impacted types; the latter were often associated with an anterior cruciate ligament tear. Tibial fractures were minimally displaced, vertically oriented fractures extending into the plateaus. Femoral fractures were Y-shaped, extending across the supracondylar region

Differences between tight and loose cultures : A 33-nation study

NARCIS (Netherlands)

Gelfand, M.J.; Raver, R.L.; Nishii, L.; Leslie, L.M.; Lun, J.; Lim, B.C.; Van de Vliert, E.

2011-01-01

With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated

Inverted Meckel's diverticulum as a cause of occult lower gastrointestinal hemorrhage

Institute of Scientific and Technical Information of China (English)

Omar M Rashid; Joseph K Ku; Masayuki Nagahashi; Akimitsu Yamada; Kazuaki Takabe

2012-01-01

Meckel's diverticulum is a common asymptomatic congenital gastrointestinal anomaly,but rarely it can present with hemorrhage.Over the last few years inverted Meckel's diverticulum has been reported in the literature with increasing frequency as an occult source of lower gastrointestinal hemorrhage.Here,we report a case of a 54-year-old male,who was referred for surgical evaluation with persistent anemia and occult blood per rectum after a work up which failed to localize the source over 12 mo,including upper and capsule endoscopy,colonoscopy,enteroclysis,Meckel scan,and tagged nuclear red blood cell scan.An abdominal computed tomography scan showed a possible mid-ileal intussusception and intraluminal mass.During the abdominal exploration,inverted Meckel's diverticulum was diagnosed and resected.We review the literature,discuss the forms in which the disease presents,the diagnostic modalities utilized,pathological findings,and treatment.Although less than 40 cases have been reported in the English literature from 1978 to 2005,19 cases have been reported in the last 6 years alone (2006-2012) due to improved diagnostic modalities.Successful diagnosis and treatment of this disease requires a high index of clinical suspicion,which is becoming increasingly relevant to general gastroenterologists.

The use of 111In-labelled platelets for scintigraphic localization of gastrointestinal bleeding with special reference to occult bleeding

International Nuclear Information System (INIS)

Gjerloeff Schmidt, K.; Waever Rasmussen, J.; Grove, O.; Andersen, D.

1986-01-01

Gamma-camera imaging of the abdomen after injection of autologous 111 In-labelled platelets was applied for localization of gastrointestinal bleeding in a study of 22 patients. In 15 studies showing scintigraphic signs of bleeding, the clinical presentation included occult bleeding in 6, melaena in 4, and bloody stools in 5 patients. Scintigraphy could be done repeatedly for up to 1 week after a single tracer injection. The time interval between the injection and scintigraphic visualization of bleeding ranged from 10 min to 68 h, being longest in cases of occult bleeding. In most cases the scintigraphic findings were supported by other diagnostic modalities, including surgical removal of presumed sources of bleeding. In seven studies without scintigraphic signs of bleeding, a probable source of bleeding was identified by other means in one patient. The 111 In-platelet method seems to be a promising method for localization of gastrointestinal bleeding which may prove particularly useful in cases of occult or recurrent bleeding

Radio scintillations observed during atmospheric occultations of Voyager: Internal gravity waves at Titan and magnetic field orientations at Jupiter and Saturn. Ph.D. Thesis

Science.gov (United States)

Hinson, D. P.

1983-01-01

The refractive index of planetary atmospheres at microwave frequencies is discussed. Physical models proposed for the refractive irregularities in the ionosphere and neutral atmosphere serve to characterize the atmospheric scattering structures, and are used subsequently to compute theoretical scintillation spectra for comparison with the Voyager occultation measurements. A technique for systematically analyzing and interpreting the signal fluctuations observed during planetary occultations is presented and applied to process the dual-wavelength data from the Voyager radio occultations by Jupiter, Saturn, and Titan. Results concerning the plasma irregularities in the upper ionospheres of Jupiter and Saturn are reported. The measured orientation of the irregularities is used to infer the magnetic field direction at several locations in the ionospheres of these two planets; the occultation measurements conflict with the predictions of Jovian magnetic field models, but generally confirm current models of Saturn's field. Wave parameters, including the vertical fluxes of energy and momentum, are estimated, and the source of the internal gravity waves discovered in Titan's upper atmosphere is considered.

Clinical relevance of occult tumor cells in lymph nodes from gastric cancer patients.

NARCIS (Netherlands)

Doekhie, F.S.; Mesker, W.H.; Krieken, J.H.J.M. van; Kok, N.F.; Hartgrink, H.H.; Kranenbarg, E.K.; Putter, H.; Kuppen, P.J.; Tanke, H.J.; Tollenaar, R.A.E.M.; Velde, C.J. van de

2005-01-01

The current method for staging in gastric cancer is not sufficient as even after a complete primary tumor resection, patients with node-negative gastric cancer suffer from disease recurrence. In this study, the relation between disease recurrence and the presence of occult tumor cells (OTC) in lymph

Tight Money, Real Interest Rates, and Inflation in Sub-Saharan Africa

OpenAIRE

Edward F. Buffie

2003-01-01

The consequences of tight monetary policy are analyzed in an optimizing currency-substitution model of a small, open economy that operates under an open capital account and a flexible exchange rate. There is a reasonably good fit between the dynamics generated by the model and the stylized facts in the tight-money episodes that occurred in Kenya in 1993 and Nigeria in 1989-91. The study's results shed light on two issues: why tight money has provoked stupendous increases in inflation and the ...

Evaluation of Refractivity Profiles from CHAMP and SAC-C GPS Radio Occultation

Science.gov (United States)

Poli, Paul; Ao, Chi On; Joiner, Joanna; delaTorreJuarez, Manuel; Hoff, Raymond

2002-01-01

The GeoForschungsZentrum's Challenging Minisatellite Payload for Geophysical Research and Application (CHAMP, Germany-US) and the Comision Nacional de Actividades Especiales' Satelite de Aplicaciones Cientificas-C (SAC-C, Argentina-US) missions are the first missions to carry a second-generation Blackjack Global Positioning System (GPS) receiver. One of the new features of this receiver is its ability to sense the lower troposphere closer to the surface than the proof-of-concept GPS Meteorology experiment (GPS/MET). Since their launch, CHAMP and SAC-C have collected thousands of GPS radio occultations, representing a wealth of measurements available for data assimilation and Numerical Weather Prediction (NWP). In order to evaluate the refractivity data derived by the Jet Propulsion Laboratory (JPL) from raw radio occultation measurements, we use Data Assimilation Office (DAO) 6-hour forecasts as an independent state of the atmosphere. We compare CHAMP and SAC-C refractivity (processed by JPL) with refractivity calculated from the DAO global fields of temperature, water vapor content and humidity. We show statistics of the differences as well as histograms of the differences.

Right upper-quadrant pain in a patient with drug abuse, secondary syphilis and occult hepatitis B virus.

Science.gov (United States)

Fielding, Cory M; Angulo, Paul

2014-01-01

To describe the etiology of hepatitis and identify occult hepatitis B virus (HBV) infection. A 40-year-old man presented with severe abdominal pain and jaundice, a history of acute HBV infection that had cleared as well as the use of acetaminophen, methamphetamine, buprenorphine and marijuana. He admitted to having had unprotected sex with multiple partners of both genders. A thorough skin examination revealed papulosquamous lesions on his penis, scrotum, upper and lower extremities and feet. Transaminases and bilirubin were elevated. His rapid plasma reagin was reactive, and hepatitis serologies showed occult HBV. Liver biopsy showed severe hepatitis, but the stains for hepatitis B surface antigen and hepatitis B core antigen were negative. The pathological findings were highly indicative of drug-induced hepatitis without evidence of chronic hepatitis, reactivation of HBV or syphilitic hepatitis. With supportive management and abstinence from drugs, his condition improved. This case describes a patient with multiple potential causes for hepatitis and highlights the importance of obtaining a detailed social history. Further, one should consider the presence of occult HBV and recognize the serologic pattern. © 2014 S. Karger AG, Basel.

Endoscopic Follow-Up of Positive Fecal Occult Blood Testing in the Ontario FOBT Project

Directory of Open Access Journals (Sweden)

Lawrence Paszat

2007-01-01

Full Text Available BACKGROUND: The Ontario FOBT Project is a pilot study of fecal occult blood testing (FOBT for colorectal cancer screening conducted among age-eligible volunteers (50 to 75 years in 12 of 37 public health regions in Ontario.

Noninvasive Prenatal Testing and Incidental Detection of Occult Maternal Malignancies.

Science.gov (United States)

Bianchi, Diana W; Chudova, Darya; Sehnert, Amy J; Bhatt, Sucheta; Murray, Kathryn; Prosen, Tracy L; Garber, Judy E; Wilkins-Haug, Louise; Vora, Neeta L; Warsof, Stephen; Goldberg, James; Ziainia, Tina; Halks-Miller, Meredith

2015-07-14

Understanding the relationship between aneuploidy detection on noninvasive prenatal testing (NIPT) and occult maternal malignancies may explain results that are discordant with the fetal karyotype and improve maternal clinical care. To evaluate massively parallel sequencing data for patterns of copy-number variations that might prospectively identify occult maternal malignancies. Case series identified from 125,426 samples submitted between February 15, 2012, and September 30, 2014, from asymptomatic pregnant women who underwent plasma cell-free DNA sequencing for clinical prenatal aneuploidy screening. Analyses were conducted in a clinical laboratory that performs DNA sequencing. Among the clinical samples, abnormal results were detected in 3757 (3%); these were reported to the ordering physician with recommendations for further evaluation. NIPT for fetal aneuploidy screening (chromosomes 13, 18, 21, X, and Y). Detailed genome-wide bioinformatics analysis was performed on available sequencing data from 8 of 10 women with known cancers. Genome-wide copy-number changes in the original NIPT samples and in subsequent serial samples from individual patients when available are reported. Copy-number changes detected in NIPT sequencing data in the known cancer cases were compared with the types of aneuploidies detected in the overall cohort. From a cohort of 125,426 NIPT results, 3757 (3%) were positive for 1 or more aneuploidies involving chromosomes 13, 18, 21, X, or Y. From this set of 3757 samples, 10 cases of maternal cancer were identified. Detailed clinical and sequencing data were obtained in 8. Maternal cancers most frequently occurred with the rare NIPT finding of more than 1 aneuploidy detected (7 known cancers among 39 cases of multiple aneuploidies by NIPT, 18% [95% CI, 7.5%-33.5%]). All 8 cases that underwent further bioinformatics analysis showed unique patterns of nonspecific copy-number gains and losses across multiple chromosomes. In 1 case, blood was

Post traumatic urinary extravasation in occult urinary obstruction: Report of three cases

Directory of Open Access Journals (Sweden)

Jyoti Bothra

2016-01-01

Full Text Available Urinary extravastion after blunt abdominal trauma is seen often and generally treated conservatively. However a blunt renal trauma causing huge amount of extravasations and symptoms disproportionate to the severity of trauma should alarm the surgeon towards an underlying occult renal pathology usually an obstruction. In this case series, we share three such experiences and their management.

GPS radio occultation technique for measurement of the atmosphere above tropical cyclones

DEFF Research Database (Denmark)

Biondi, Riccardo; Neubert, Torsten; Syndergaard, Stig

2009-01-01

Water vapour transport to the upper troposphere (UT) and lower stratosphere (LS) by deep convective storms affects the radiation balance of the atmosphere and has been proposed as an important component of climate change. The aim of the work presented here is to understand if the GPS Radio Occult...... 2008 and reached a maximum intensity of Category 3....

Pluto occultation on 2015 June 29 UTC with central flash and atmospheric spikes just before the New Horizons flyby

Science.gov (United States)

Pasachoff, Jay M.; Babcock, Bryce A.; Durst, Rebecca F.; Seeger, Christina H.; Levine, Stephen E.; Bosh, Amanda S.; Person, Michael J.; Sickafoose, Amanda A.; Zuluaga, Carlos A.; Kosiarek, Molly R.; Abe, Fumio; Nagakane, Masayuki; Suzuki, Daisuke; Tristram, Paul J.; Arredondo, Anicia

2017-11-01

We observed the occultation by Pluto of a 12th magnitude star, one of the two brightest occultation stars ever in our dozen years of continual monitoring of Pluto's atmosphere through such studies, on 2015 June 29 UTC. At the Univ. of Canterbury Mt. John Observatory (New Zealand), under clear skies throughout, we used a POETS frame-transfer CCD at 10 Hz with GPS timing on the 1-m McLellan telescope as well as an infrared camera on an 0.6-m telescope and three-color photometry at a slower cadence on a second 0.6-m telescope. At the Auckland Observatory, we used a POETS and a PICO on 0.5-m and 0.4-m telescopes, with 0.4 s and 2 s cadences, respectively, obtaining ingress observations before clouds moved in. The Mt. John light curves show a central flash, indicating that we were close to the center of the occultation path. Analysis of our light curves show that Pluto's atmosphere remains robust. The presence of spikes at both sites in the egress and ingress shows atmospheric layering. We coordinated our observations with aircraft observations (Bosh et al., 2017) with the Stratospheric Observatory for Infrared Astronomy (SOFIA). Our chords helped constrain the path across Pluto that SOFIA saw. Our ground-based and airborne stellar-occultation effort came only just over two weeks of Earth days and two Pluto days before the flyby of NASA's New Horizons spacecraft.

Immunochemical faecal occult blood tests have superior stability and analytical performance characteristics over guaiac-based tests in a controlled in vitro study.

LENUS (Irish Health Repository)

Lee, Chun Seng

2011-06-01

The aims of this study were (1) to determine the measurement accuracy of a widely used guaiac faecal occult blood test (gFOBT) compared with an immunochemical faecal occult blood test (iFOBT) during in vitro studies, including their analytical stability over time at ambient temperature and at 4°C; and (2) to compare analytical imprecision and other characteristics between two commercially available iFOBT methods.

Indeling occulte tumorcellen in de lymfklieren bij patiënten met darmkanker onvoldoende betrouwbaar

NARCIS (Netherlands)

van der Zaag, E. S.; Welling, L.; Peters, H. M.; van de Vijver, M. J.; Bemelman, W. A.; Buskens, C. J.

2011-01-01

OBJECTIVE: To assess interobserver agreement between pathologists in judging photographs of lymph node preparations of occult tumour cells of patients with colon cancer. DESIGN: Descriptive and comparative study of interobserver variability. METHODS: All lymph nodes of 82 pN0 patients with colon

Diagnosis of occult abdominal abscesses using radioisotopes

International Nuclear Information System (INIS)

Koch, B.; Schroth, H.J.; Wolf, N.; Wilhelm, H.; Universitaet des Saarlandes, Homburg/Saar

1983-01-01

Occult intraperitoneal abscesses are difficult to localize and dispose of. Therefore, a method of examination is needed that is specific, can be used at any time, is not expensive, and yields early results within 2-3 h. This seems possible with a new method of examination. sup(99m)Tc-Sn-colloid was used to label autologous polymorphonuclear leukocytes which, when reinjected, emigrate to the site of the suspected abscess. Standard scintigraphy localizes the labeled inflammatory cells. Scans were performed in 57 surgical patients with good results. 23 (40,4%) patients had true negative results; 28 (49,1%) scans represented intraperitoneal abscesses; 5 (8,8%) scans demonstrated true positive extraperitoneal inflammations. Only 1 (1,7%) scan was false positive. (orig.) [de

Diagnosis of an isolated occult fracture of the posterior margin of the tibia with the SPECT/CT; Diagnostic d'une fracture occulte isolee de la marge posterieure du tibia par la TEMP-TDM

Energy Technology Data Exchange (ETDEWEB)

Bourdon, A.; Granier, P.; Mourad, M. [Centre Hospitalier de Carcassonne Antoine-Gayraud, Service de Medecine Nucleaire, 11 - Carcassonne (France)

2007-12-15

We report the case of a 56-year-old woman, investigated for pains of the right ankle related to a trauma of an unspecified mechanism. The radiographic assessment was negative. The {sup 99m}Tc-HDP 3-phase bone scintigraphy highlighted, on the blood pool and the delayed images, a located lesion on the right ankle. The single photon emission computerized tomography guided by computerized tomography (SPECT-CT) showed a focused uptake on the posterior margin of the right tibia and a sharp lucent line within the tomo-scintigraphy spot of uptake. The diagnosis accepted was an isolated occult fracture of the posterior margin of the right tibia. The contribution of the {sup 99m}Tc-HDP 3-phase bone scintigraphy combined with the SPECT-CT in the diagnosis of the occult fractures is discussed. (N.C.)

Atmospheric Drag, Occultation ‘N’ Ionospheric Scintillation (ADONIS mission proposal

Directory of Open Access Journals (Sweden)

Hettrich Sebastian

2015-01-01

Full Text Available The Atmospheric Drag, Occultation ‘N’ Ionospheric Scintillation mission (ADONIS studies the dynamics of the terrestrial thermosphere and ionosphere in dependency of solar events over a full solar cycle in Low Earth Orbit (LEO. The objectives are to investigate satellite drag with in-situ measurements and the ionospheric electron density profiles with radio occultation and scintillation measurements. A constellation of two satellites provides the possibility to gain near real-time data (NRT about ionospheric conditions over the Arctic region where current coverage is insufficient. The mission shall also provide global high-resolution data to improve assimilative ionospheric models. The low-cost constellation can be launched using a single Vega rocket and most of the instruments are already space-proven allowing for rapid development and good reliability. From July 16 to 25, 2013, the Alpbach Summer School 2013 was organised by the Austrian Research Promotion Agency (FFG, the European Space Agency (ESA, the International Space Science Institute (ISSI and the association of Austrian space industries Austrospace in Alpbach, Austria. During the workshop, four teams of 15 students each independently developed four different space mission proposals on the topic of “Space Weather: Science, Missions and Systems”, supported by a team of tutors. The present work is based on the mission proposal that resulted from one of these teams’ efforts.

Outcome of early detection and radiotherapy for occult spinal cord compression

International Nuclear Information System (INIS)

Venkitaraman, Ramachandran; Barbachano, Yolanda; Dearnaley, David P.; Parker, Christopher C.; Khoo, Vincent; Huddart, Robert A.; Eeles, Rosalind; Horwich, Alan; Aslam Sohaib, S.

2007-01-01

Retrospective analysis in 150 patients with metastatic prostate cancer was conducted to determine whether early detection with MRI spine and treatment of clinically occult spinal cord compromise (SCC) facilitate preservation of neurologic function. Our results suggest that prophylactic radiotherapy for patients with back pain or radiological SCC without neurologic deficit may facilitate preservation of neurologic function. Thus MRI surveillance for SCC may be important for prostate cancer patients with bone metastases

Clinical features of secondary glaucoma caused by lens suspensory ligament laxity or occult subluxation

Directory of Open Access Journals (Sweden)

Yi Ma

2018-04-01

Full Text Available AIM: To investigate the clinical characteristics of secondary glaucoma caused by lens suspensory ligament laxity or occult subluxation, and to analyze the influence of operation on visual acuity and intraocular pressure(IOP. METHODS: Totally 38 cases(38 eyesof the secondary glaucoma caused by lens suspensory ligament laxity or occult subluxation in ophthalmology department of our hospital from December 2014 to December 2016 were enrolled and their medical records were analyzed retrospectively to observe the clinical characteristics of glaucoma. Preoperative mydriasis was carried out and surgical methods were chosen according to the lenses location and extent of suspensory ligament. Preoperative and postoperative anterior chamber depth, corneal endothelial cell density, IOP, visual field, visual acuity and complications were analyzed. RESULTS: The average intraocular pressure was 18.17±1.43mmHg at postoperatively 10d, which was significantly lower than 38.77±2.45mmHg before operation, the difference had statistical significance(PP>0.05. The postoperative anterior chamber depth was 2.45±0.44mm, which was significantly higher than 1.23±0.35mm before operation, the difference had statistical significance(P2 and decreased significantly, compared with 1735.32±340.32/mm2 before operation, the difference had statistical significance(PCONCLUSION: Clinical symptoms and signs of secondary glaucoma in patients with lens suspensory ligament laxity or occult subluxation are more complex, which needs to be distinguished with other types of glaucoma in clinical treatment, and its surgical methods shall be chosen according to different suspensory ligament site and lens subluxation scope.

Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs

Energy Technology Data Exchange (ETDEWEB)

Stephen Holditch; A. Daniel Hill; D. Zhu

2007-06-19

The objectives of this project are to develop and test new techniques for creating extensive, conductive hydraulic fractures in unconventional tight gas reservoirs by statistically assessing the productivity achieved in hundreds of field treatments with a variety of current fracturing practices ranging from 'water fracs' to conventional gel fracture treatments; by laboratory measurements of the conductivity created with high rate proppant fracturing using an entirely new conductivity test - the 'dynamic fracture conductivity test'; and by developing design models to implement the optimal fracture treatments determined from the field assessment and the laboratory measurements. One of the tasks of this project is to create an 'advisor' or expert system for completion, production and stimulation of tight gas reservoirs. A central part of this study is an extensive survey of the productivity of hundreds of tight gas wells that have been hydraulically fractured. We have been doing an extensive literature search of the SPE eLibrary, DOE, Gas Technology Institute (GTI), Bureau of Economic Geology and IHS Energy, for publicly available technical reports about procedures of drilling, completion and production of the tight gas wells. We have downloaded numerous papers and read and summarized the information to build a database that will contain field treatment data, organized by geographic location, and hydraulic fracture treatment design data, organized by the treatment type. We have conducted experimental study on 'dynamic fracture conductivity' created when proppant slurries are pumped into hydraulic fractures in tight gas sands. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially; we pump proppant/frac fluid slurries into a fracture cell, dynamically placing the proppant just as it occurs in the field. From such tests, we expect to gain new insights into some of the critical

Design and Verification of External Occulters for Direct Imaging of Extrasolar Planets

Science.gov (United States)

Cady, Eric

2011-01-01

An occulter is an optical element which is placed in front of the telescope to block most of the light from a star before it reaches the optics inside, without blocking the planet.In our case, we use two spacecraft ying in formation: First has its edge shaped to cancel the starlight Second is the telescope which images the star and planet

First lunar occultation results from the 2.4 m Thai national telescope equipped with ULTRASPEC

Energy Technology Data Exchange (ETDEWEB)

Richichi, A.; Irawati, P.; Soonthornthum, B. [National Astronomical Research Institute of Thailand, 191 Siriphanich Building, Huay Kaew Road, Suthep, Muang, Chiang Mai 50200 (Thailand); Dhillon, V. S. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Marsh, T. R., E-mail: andrea4work@gmail.com [Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom)

2014-11-01

The recently inaugurated 2.4 m Thai National Telescope (TNT) is equipped with, among other instruments, the ULTRASPEC low-noise, frame-transfer EMCCD camera. At the end of its first official observing season, we report on the use of this facility to record high time resolution imaging using small detector subarrays with a sampling as fast as several 10{sup 2} Hz. In particular, we have recorded lunar occultations of several stars that represent the first contribution to this area of research made from Southeast Asia with a telescope of this class. Among the results, we discuss an accurate measurement of α Cnc, which has been reported previously as a suspected close binary. Attempts by several authors to resolve this star have so far met with a lack of unambiguous confirmation. With our observation we are able to place stringent limits on the projected angular separation (<0.''003) and brightness (Δm > 5) of a putative companion. We also present a measurement of the binary HR 7072, which extends considerably the time coverage available for its yet undetermined orbit. We discuss our precise determination of the flux ratio and projected separation in the context of other available data. We conclude by providing an estimate of the performance of ULTRASPEC at TNT for lunar occultation work. This facility can help to extend the lunar occultation technique in a geographical area where no comparable resources were available until now.

Occult Hepatitis B Virus infection in ART-Naive HIV-Infected Patients seen at a Tertiary Care Centre in North India

Directory of Open Access Journals (Sweden)

Singh Sarman

2010-03-01

Full Text Available Abstract Background Co-infections of hepatitis B and C viruses are frequent with HIV due to shared routes of transmission. In most of the tertiary care health settings, HIV reactive patients are routinely tested for HBsAg and anti-HCV antibodies to rule out these co-infections. However, using the routine serological markers one can only detect active HBV infection while the occult HBV infection may be missed. There is insufficient data from India on HIV-HBV co-infection and even scarce on occult HBV infection in this group. Methods We estimated the burden of HBV infection in patients who were tested positive for HIV at a tertiary care centre in north India. We also attempted to determine the prevalence and clinical characteristics of occult HBV infection among these treatment-naïve patients and compare their demographic features with other HIV patients. During a period of 6 years between January 2002 to December 2007, 837 HIV positive patients (631 males and 206 females (M: F :: 3.06:1 were tested for serological markers of HBV (HBsAg and HCV (anti-HCV antibodies infections in our laboratory. For comparison 1000 apparently healthy, HIV-negative organ donors were also included in the study. Data on demographics, sexual behaviour, medical history, laboratory tests including the serum ALT and CD4 count of these patients were recorded. A sub-group of 53 HBsAg negative samples from HIV positive patients were assessed for anti-HBs, anti-HBc total (IgG+IgM and HBV-DNA using a highly sensitive qualitative PCR and analysed retrospectively. Results Overall, 7.28% of HIV positive patients showed presence of HBsAg as compared to 1.4% in the HIV negative control group. The prevalence of HBsAg was higher (8.55% in males than females (3.39%. The study revealed that occult HBV infection with detectable HBV-DNA was prevalent in 24.5% of patients positive for anti-HBc antibodies; being 45.5% in HBsAg negative patients. Most importantly the occult infection was

Tightness of M-estimators for multiple linear regression in time series

DEFF Research Database (Denmark)

Johansen, Søren; Nielsen, Bent

We show tightness of a general M-estimator for multiple linear regression in time series. The positive criterion function for the M-estimator is assumed lower semi-continuous and sufficiently large for large argument: Particular cases are the Huber-skip and quantile regression. Tightness requires...

A game of two discs: a case of non-contiguous and occult cervical spine injury in a rugby player.

Science.gov (United States)

O'Sullivan, Michael D; Piggot, Robert; Jaddan, Mutaz; McCabe, John P

2016-03-14

The aim of this case report was to highlight the application of magnetic resonance imaging (MRI) in elucidating serious and occult injuries in a single case of hyperflextion injury of a patient cervical spine (C-Spine). A chart and radiology review was performed to establish the sequence of care and how the results of imaging studies influenced the clinical management in this trauma case. Plain radiographs and computed tomography (CT) imaging modalities of the C-Spine revealed bilateral C4/C5 facetal subluxation with no obvious fractures; however, the MR imaging of the C-Spine revealed a non-contiguous and occult injury to C6/C7 disc with a posterior annular tear and associated disc extrusion. This altered the operative intervention that was initially planned. MR imaging proved an invaluable diagnostic addition in this particular case of cervical trauma in a rugby player following a hyperflextion injury, by revealing a serious non-contiguous and occult injury of the C-Spine. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

Local thermal-hydraulic behaviour in tight 7-rod bundles

International Nuclear Information System (INIS)

Cheng, X.; Yu, Y.Q.

2009-01-01

Advanced water-cooled reactor concepts with tight lattices have been proposed worldwide to improve the fuel utilization and the economic competitiveness. In the present work, experimental investigations were performed on thermal-hydraulic behaviour in tight hexagonal 7-rod bundles under both single-phase and two-phase conditions. Freon-12 was used as working fluid due to its convenient operating parameters. Tests were carried out under both single-phase and two-phase flow conditions. Rod surface temperatures are measured at a fixed axial elevation and in various circumferential positions. Test data with different radial power distributions are analyzed. Measured surface temperatures of unheated rods are used for the assessment of and comparison with numerical codes. In addition, numerical simulation using sub-channel analysis code MATRA and the computational fluid dynamics (CFD) code ANSYS-10 is carried out to understand the experimental data and to assess the validity of these codes in the prediction of flow and heat transfer behaviour in tight rod bundle geometries. Numerical results are compared with experimental data. A good agreement between the measured temperatures on the unheated rod surface and the CFD calculation is obtained. Both sub-channel analysis and CFD calculation indicates that the turbulent mixing in the tight rod bundle is significantly stronger than that computed with a well established correlation.

[Occult medicine in the 20th century: pharmacotherapy by Demeter Georgievitz-Weitzer, known as Surya (1873 - 1949)].

Science.gov (United States)

Helmstädter, Axel

2011-01-01

Demeter Georgievitz-Weitzer (1873-1949), called "Surya", Sanskrit for "sun", was an important representative of medical occultism in the first half of the 20th century. He worked as a journal editor and published a 13-volume book series about occult medicine, mainly written by himself. His hypotheses were closely related to the "Lebensreform" movement around 1900. Regarding diagnostics, he relied on astrology, cheiromancy, and clairvoyance, while therapeutics were dominated by diet and spagyric remedies according to Cesare Mattei (1809-1896) and Carl-Friedrich Zimpel (1801-1879). In his later years, he developed his own healing system, initially comprising eight, later only two preparations. Surya remedies were commercially available until the end of the 20th century,

The prototype cameras for trans-Neptunian automatic occultation survey

Science.gov (United States)

Wang, Shiang-Yu; Ling, Hung-Hsu; Hu, Yen-Sang; Geary, John C.; Chang, Yin-Chang; Chen, Hsin-Yo; Amato, Stephen M.; Huang, Pin-Jie; Pratlong, Jerome; Szentgyorgyi, Andrew; Lehner, Matthew; Norton, Timothy; Jorden, Paul

2016-08-01

The Transneptunian Automated Occultation Survey (TAOS II) is a three robotic telescope project to detect the stellar occultation events generated by TransNeptunian Objects (TNOs). TAOS II project aims to monitor about 10000 stars simultaneously at 20Hz to enable statistically significant event rate. The TAOS II camera is designed to cover the 1.7 degrees diameter field of view of the 1.3m telescope with 10 mosaic 4.5k×2k CMOS sensors. The new CMOS sensor (CIS 113) has a back illumination thinned structure and high sensitivity to provide similar performance to that of the back-illumination thinned CCDs. Due to the requirements of high performance and high speed, the development of the new CMOS sensor is still in progress. Before the science arrays are delivered, a prototype camera is developed to help on the commissioning of the robotic telescope system. The prototype camera uses the small format e2v CIS 107 device but with the same dewar and also the similar control electronics as the TAOS II science camera. The sensors, mounted on a single Invar plate, are cooled to the operation temperature of about 200K as the science array by a cryogenic cooler. The Invar plate is connected to the dewar body through a supporting ring with three G10 bipods. The control electronics consists of analog part and a Xilinx FPGA based digital circuit. One FPGA is needed to control and process the signal from a CMOS sensor for 20Hz region of interests (ROI) readout.

Between occultism and drama. Henrik Ibsen and Aleister Crowley

Directory of Open Access Journals (Sweden)

Giuliano D' Amico

2015-02-01

Full Text Available The article investigates the references to the works of Henrik Ibsen that the writer and occultist Aleister Crowley scattered in his writings around the turn of the 20th century, in the early phase of his career as a writer and occultist. Crowley’s reading of Ibsen has a marked a socio-political bent, especially in his interpretation of the work of the Norwegian playwright as an act of rebellion against the bourgeois (and for Crowley, Victorian system of values. Also, such view is enriched by a spiritual and individualistic interpretation of Ibsen as an “Artist”, i.e., in the light of Crowley’s occult doctrine, Thelema, of an individual who has found his own “Will” and can inspire others to do so. Such social and spiritual interpretations of Ibsen on Crowley’s part found their literary realization in his one-act play The Mother’s Tragedy (1899. The article claims that Crowley’s reading of Ibsen can give some new insight in the mechanisms of reception of the Norwegian playwright, by opening up for a reading of some of his plays within an occult discourse. Also, it is an occasion to treat Crowley – a figure that was constantly present in the European cultural and literary life of the last decade of the 19th century and of the first five decades of the 20th – with a different attitude than the irony and disdain to which he is often exposed.

The Effect of Early Detection of Occult Brain Metastases in HER2-Positive Breast Cancer Patients on Survival and Cause of Death

International Nuclear Information System (INIS)

Niwinska, Anna; Tacikowska, Malgorzata; Murawska, Magdalena

2010-01-01

Purpose: The aim of the study is to evaluate disease-free survival, survival from the detection of brain metastases, overall survival, and cause of death in patients with occult brain metastases (Group I) vs. patients with symptomatic brain metastases (Group II). Methods and Materials: In 80 HER2-positive breast cancer patients, treated with trastuzumab and cytostatic agents for metastatic disease, magnetic resonance imaging screening of the brain was performed, and in 29 patients (36%) occult brain metastasis was detected (Group I). Whole-brain radiotherapy was delivered to Group I. This first group was compared with 52 patients who had symptomatic brain metastases (Group II) and was treated the same way, at the same clinic, during the same time period. Results: Median disease-free survival was 17 months in Group I and 19.9 months in Group II (p = 0.58). The median time interval between the dissemination of the disease and the detection of occult or symptomatic brain metastases was 9 and 15 months, respectively (p = 0.11). When the brain metastases were detected, the median survival was 9 and 8.78 months, respectively (p = 0.80). The median overall survival was 53 and 51 months, respectively (p = 0.94). In the group with occult brain metastases (Group I) 16% of patients died because of progression within the brain. In the group with symptomatic brain metastases (Group II) the rate of cerebral death was 48% (p = 0.009). Conclusions: Whole-brain radiotherapy of occult brain metastases in HER2-positive breast cancer patients with visceral dissemination produces a three-fold decrease in cerebral deaths but does not prolong survival.

Experimental study on reflooding in advanced tight lattice PWR

International Nuclear Information System (INIS)

Hori, K.; Kodama, J.; Teramae, T.

2000-01-01

This paper is related to the experimental study on the feasibility of core cooling by re-flooding in a large break loss of coolant accident (LOCA) for the advanced tight lattice pressurized water reactor (PWR). The tight lattice core design should be adopted to improve the conversion ratio. Major one of the key questions of such tight lattice core is the cooling capability under the re-flood condition in a large break LOCA. Forced feed bottom re-flooding experiments have been performed by use of a 4x4 triangular array rod bundle. The rod gap is 0.5 mm, 1.0 mm, or 1.5 mm. The measured peak temperature is below around 1273 K even in case of 1.0/0.5 mm rod gap. And, the evaluation based on the experimental results of rod temperatures and core pressure drop also shows that the core cooling under re-flooding condition is feasible. (author)

Laser fluorescence bronchoscope for localization of occult lung tumors

International Nuclear Information System (INIS)

Profio, A.E.; Doiron, D.R.; King, E.G.

1979-01-01

A system for imaging occult bronchogenic carcinoma by the fluorescence of previously-injected, tumor-specific compound hematoporphyrin-derivative has been assembled and successfully used to locate a tumor l mm thick. The violet excitation source is a krypton ion laser coupled to fused quartz fiber light conductor. An electrostatic image intensifier attached to a standard flexible fiberoptic bronchoscope provides a bright image even at relatively low irradiance. A red secondary filter rejects most reflected background and autofluorescence. Sensitivity and contrast capability of the system should permit detection of a tumor less than 0.1 mm thick

Transferable tight-binding model for strained group IV and III-V materials and heterostructures

Science.gov (United States)

Tan, Yaohua; Povolotskyi, Michael; Kubis, Tillmann; Boykin, Timothy B.; Klimeck, Gerhard

2016-07-01

It is critical to capture the effect due to strain and material interface for device level transistor modeling. We introduce a transferable s p3d5s* tight-binding model with nearest-neighbor interactions for arbitrarily strained group IV and III-V materials. The tight-binding model is parametrized with respect to hybrid functional (HSE06) calculations for varieties of strained systems. The tight-binding calculations of ultrasmall superlattices formed by group IV and group III-V materials show good agreement with the corresponding HSE06 calculations. The application of the tight-binding model to superlattices demonstrates that the transferable tight-binding model with nearest-neighbor interactions can be obtained for group IV and III-V materials.

Lunar occultations for gamma-ray source measurements

Science.gov (United States)

Koch, David G.; Hughes, E. B.; Nolan, Patrick L.

1990-01-01

The unambiguous association of discrete gamma-ray sources with objects radiating at other wavelengths, the separation of discrete sources from the extended emission within the Galaxy, the mapping of gamma-ray emission from nearby galaxies and the measurement of structure within a discrete source cannot presently be accomplished at gamma-ray energies. In the past, the detection processes used in high-energy gamma-ray astronomy have not allowed for good angular resolution. This problem can be overcome by placing gamma-ray detectors on the moon and using the horizon as an occulting edge to achieve arcsec resolution. For purposes of discussion, this concept is examined for gamma rays above 100 MeV for which pair production dominates the detection process and locally-generated nuclear gamma rays do not contribute to the background.

Tightness of voter model interfaces

Czech Academy of Sciences Publication Activity Database

Sturm, A.; Swart, Jan M.

2008-01-01

Roč. 13, - (2008), s. 165-174 ISSN 1083-589X R&D Projects: GA ČR GA201/06/1323; GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10750506 Keywords : long range voter model * swapping voter model * interface tightness * exclusion process Subject RIV: BD - Theory of Information Impact factor: 0.392, year: 2008 http://www.emis.de/journals/EJP-ECP/_ejpecp/index.html

Air-cooling mathematical analysis as inferred from the air-temperature observation during the 1st total occultation of the Sun of the 21st century at Lusaka, Zambia

Science.gov (United States)

Peñaloza-Murillo, Marcos A.; Pasachoff, Jay M.

2015-04-01

We analyze mathematically air temperature measurements made near the ground by the Williams College expedition to observe the first total occultation of the Sun [TOS (commonly known as a total solar eclipse)] of the 21st century in Lusaka, Zambia, in the afternoon of June 21, 2001. To do so, we have revisited some earlier and contemporary methods to test their usefulness for this analysis. Two of these methods, based on a radiative scheme for solar radiation modeling and that has been originally applied to a morning occultation, have successfully been combined to obtain the delay function for an afternoon occultation, via derivation of the so-called instantaneous temperature profiles. For this purpose, we have followed the suggestion given by the third of these previously applied methods to calculate this function, although by itself it failed to do so at least for this occultation. The analysis has taken into account the limb-darkening, occultation and obscuration functions. The delay function obtained describes quite fairly the lag between the solar radiation variation and the delayed air temperature measured. Also, in this investigation, a statistical study has been carried out to get information on the convection activity produced during this event. For that purpose, the fluctuations generated by turbulence has been studied by analyzing variance and residuals. The results, indicating an irreversible steady decrease of this activity, are consistent with those published by other studies. Finally, the air temperature drop due to this event is well estimated by applying the empirical scheme given by the fourth of the previously applied methods, based on the daily temperature amplitude and the standardized middle time of the occultation. It is demonstrated then that by using a simple set of air temperature measurements obtained during solar occultations, along with some supplementary data, a simple mathematical analysis can be achieved by applying of the four

Aplastic crisis in occult hereditary spherocytosis caused by human parvovirus (HPV B19).

Science.gov (United States)

Rappaport, E S; Quick, G; Ransom, D; Helbert, B; Frankel, L S

1989-02-01

We have reported a case of aplastic crisis occurring in an 11-year-old black boy with occult hereditary spherocytosis. An etiologic diagnosis of human parvovirus (HPV) B19 infection was confirmed serologically. The Coulter Model S + IV proved useful for both diagnosis and treatment monitoring through serial histograms. The relationship of HPV infection and aplastic crisis is discussed.

Tight turns

CERN Multimedia

Anaïs Schaeffer

2012-01-01

The Italian National Institute for Nuclear Physics (INFN) has successfully tested the first model of a new fast-ramping curved dipole magnet. This is great news for CERN, which sees the advance as holding potential for the future of the SPS.   The first model of a new fast-ramping curved dipole magnet being prepared for cryogenic testing at the LASA laboratory (INFN Milano, Italy). On 16 July INFN introduced an innovative dipole magnet. With a length of some 4 metres, it can produce a 4.5 Tesla magnetic field and achieve a tighter bend than ever before (the bending radius has been squeezed to a remarkable 66.7 metres). This new magnet was designed in the first instance for GSI’s SIS300 synchrotron (in Germany), which will require 60 dipoles of this type. "Achieving such a tight bend demanded a major R&D effort," stressed Pasquale Fabbricatore, the spokesman of the INFN collaboration responsible for the magnet’s development. "We had to not o...

Prognosis for Mammographically Occult, Early-Stage Breast Cancer Patients Treated With Breast-Conservation Therapy

International Nuclear Information System (INIS)

Yang, Tzu-I. J.; Yang Qifeng; Haffty, Bruce G.; Moran, Meena S.

2010-01-01

Purpose: To compare mammographically occult (MamOcc) and mammographically positive (MamPos) early-stage breast cancer patients treated with breast-conservation therapy (BCT), to analyze differences between the two cohorts. Methods and Materials: Our two cohorts consisted of 214 MamOcc and 2168 MamPos patients treated with BCT. Chart reviews were conducted to assess mammogram reports and method of detection. All clinical-pathologic and outcome parameters were analyzed to detect differences between the two cohorts. Results: Median follow-up was 7 years. There were no differences in final margins, T stage, nodal status, estrogen/progesterone receptor status, or 'triple-negative' status. Significant differences included younger age at diagnosis (p o histology (p < 0.0001). At 10 years, the differences in overall survival, cause-specific survival, and distant relapse between the two groups did not differ significantly. The MamOcc cohort had more breast relapses (15% vs. 8%; p = 0.0357), but on multivariate analysis this difference was not significant (hazard ratio 1.0, 95% confidence interval 0.993-1.007, p = 0.9296). Breast relapses were mammographically occult in 32% of the MamOcc and 12% of the MamPos cohorts (p = 0.0136). Conclusions: Although our study suggests that there are clinical-pathologic variations for the MamOcc cohort vs. MamPos patients that may ultimately affect management, breast relapse after BCT was not significantly different. Breast recurrences were more often mammographically occult in the MamOcc cohort; consideration should be given to closer follow-up and alternative imaging strategies (ultrasound, breast MRI) for routine posttreatment examination. To our knowledge, this represents the largest series addressing the prognostic significance of MamOcc cancers treated with BCT.

Prediction of Occult Invasive Disease in Ductal Carcinoma in Situ Using Deep Learning Features.

Science.gov (United States)

Shi, Bibo; Grimm, Lars J; Mazurowski, Maciej A; Baker, Jay A; Marks, Jeffrey R; King, Lorraine M; Maley, Carlo C; Hwang, E Shelley; Lo, Joseph Y

2018-03-01

The aim of this study was to determine whether deep features extracted from digital mammograms using a pretrained deep convolutional neural network are prognostic of occult invasive disease for patients with ductal carcinoma in situ (DCIS) on core needle biopsy. In this retrospective study, digital mammographic magnification views were collected for 99 subjects with DCIS at biopsy, 25 of which were subsequently upstaged to invasive cancer. A deep convolutional neural network model that was pretrained on nonmedical images (eg, animals, plants, instruments) was used as the feature extractor. Through a statistical pooling strategy, deep features were extracted at different levels of convolutional layers from the lesion areas, without sacrificing the original resolution or distorting the underlying topology. A multivariate classifier was then trained to predict which tumors contain occult invasive disease. This was compared with the performance of traditional "handcrafted" computer vision (CV) features previously developed specifically to assess mammographic calcifications. The generalization performance was assessed using Monte Carlo cross-validation and receiver operating characteristic curve analysis. Deep features were able to distinguish DCIS with occult invasion from pure DCIS, with an area under the receiver operating characteristic curve of 0.70 (95% confidence interval, 0.68-0.73). This performance was comparable with the handcrafted CV features (area under the curve = 0.68; 95% confidence interval, 0.66-0.71) that were designed with prior domain knowledge. Despite being pretrained on only nonmedical images, the deep features extracted from digital mammograms demonstrated comparable performance with handcrafted CV features for the challenging task of predicting DCIS upstaging. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Impact of Air Tightness on the Evaluation of Building Energy Performance in Lithuania

Directory of Open Access Journals (Sweden)

Jolanta Šadauskienė

2014-08-01

Full Text Available In order to fulfil the European Energy Performance of Buildings Directive (EPBD requirements for the reduction of energy consumption, European national requirements have been created for building envelope thermal properties and calculation methodology to determine if building energy efficiency is created. This is however not true in all methodologies. The necessity of building air tightness appears only for new A class buildings, and there are no requirements for air tightness for other building classes. Therefore, the aim of this work is to improve the methodology for the calculation of energy efficiency of buildings, while taking into account the air tightness of the buildings. In order to achieve this aim, the sum energy consumption of investigated buildings was calculated, energy efficiency classes were determined, air tightness of the buildings was measured, and reasons for insufficient air tightness were analyzed. Investigation results show that the average value of air tightness of A energy efficiency class buildings is 0.6 h−1. The results of other investigated buildings, corresponding to B and C energy efficiency classes, show insufficient air tightness (the average n50 value is 6 h−1; herewith, energy consumption for heating is higher than calculated, according to the energy efficiency methodology. This paper provides an energy performance evaluation scheme, under which performed evaluation of energy performance of buildings ensures high quality construction work, building durability, and the reliability of heat-loss calculations.

Intestinal epithelial barrier function and tight junction proteins with heat and exercise

DEFF Research Database (Denmark)

Dokladny, Karol; Zuhl, Micah N; Moseley, Pope L

2016-01-01

A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. A dysfunctional or "leaky" intestinal tight junction barrier allows augmented perme...

Gas leak tightness of SiC/SiC composites at elevated temperature

Energy Technology Data Exchange (ETDEWEB)

Hayasaka, Daisuke, E-mail: hayasaka@oasis.muroran-it.ac.jp [OASIS, Muroran Institute of Technology, Muroran, Hokkaido (Japan); Graduate School of Engineering, Muroran Institute of Technology, Muroran, Hokkaido (Japan); Park, Joon-Soo. [OASIS, Muroran Institute of Technology, Muroran, Hokkaido (Japan); Kishimoto, Hirotatsu [OASIS, Muroran Institute of Technology, Muroran, Hokkaido (Japan); Graduate School of Engineering, Muroran Institute of Technology, Muroran, Hokkaido (Japan); Kohyama, Akira [OASIS, Muroran Institute of Technology, Muroran, Hokkaido (Japan)

2016-11-01

Highlights: • NITE-SiC/SiC has extremely densified microstructure compared with other SiC/SiC composite like CVI. • Excellent helium and hydrogen gas-leak tightness of SiC/SiC composites by DEMO-NITE method from prototype industrialization production line was presented. • The excellence against stainless steel and Zircaloy at elevated temperature, together with generic excellent properties of SiC will be inevitable for innovative blanket and divertors for DEMO- and power- fusion reactors. - Abstract: SiC/SiC composite materials are attractive candidates for high heat flux components and blanket of fusion reactor, mainly due to their high temperature properties, radiation damage tolerance and low induced radioactivity. One of the challenges for SiC/SiC application in fusion reactors is to satisfy sufficient gas leak tightness of hydrogen and helium isotopes. Although many efforts have been carried-out, SiC/SiC composites by conventional processes have not been successful to satisfy the requirements, except SiC/SiC composites by NITE-methods. Toward the early realization of SiC/SiC components into fusion reactor systems process development of NITE-process has been continued. Followed to the brief introduction of recently developed DEMO-NITE process, baseline properties and hydrogen and helium gas leak tightness is presented. SiC/SiC claddings with 10 mm in diameter and 1 mm in wall thickness are tested by gas leak tightness system developed. The leak tightness measurements are done room temperature to 400 °C. Excellent gas leak tightness equivalent or superior to Zircaloy claddings for light water fission reactors is confirmed. The excellent gas leak tightness suggests nearly perfect suppression of large gas leak path in DEMO-NITE SiC/SiC.

Thermal structure of intense convective clouds derived from GPS radio occultations

DEFF Research Database (Denmark)

Biondi, Riccardo; Randel, W. J.; Ho, S. -P.

2012-01-01

Thermal structure associated with deep convective clouds is investigated using Global Positioning System (GPS) radio occultation measurements. GPS data are insensitive to the presence of clouds, and provide high vertical resolution and high accuracy measurements to identify associated temperature...... behavior. Deep convective systems are identified using International Satellite Cloud Climatology Project (ISCCP) satellite data, and cloud tops are accurately measured using Cloud-Aerosol Lidar with Orthogonal Polarization (CALIPSO) lidar observations; we focus on 53 cases of near-coincident GPS...

Thermal structure of intense convective clouds derived from GPS radio occultations

DEFF Research Database (Denmark)

Biondi, Riccardo; Randel, W. J.; Ho, S.-P.

2011-01-01

Thermal structure associated with deep convective clouds is investigated using Global Positioning System (GPS) radio occultation measurements. GPS data are insensitive to the presence of clouds, and provide high vertical resolution and high accuracy measurements to identify associated temperature...... behavior. Deep convective systems are identified using International Satellite Cloud Climatology Project (ISCCP) satellite data, and cloud tops are accurately measured using Cloud-Aerosol Lidar with Orthogonal Polarization (CALIPSO) lidar observations; we focus on 53 cases of near-coincident GPS...

Microwave emulations and tight-binding calculations of transport in polyacetylene

Energy Technology Data Exchange (ETDEWEB)

Stegmann, Thomas, E-mail: stegmann@icf.unam.mx [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, 62210 Cuernavaca (Mexico); Franco-Villafañe, John A., E-mail: jofravil@fis.unam.mx [Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, 72570 Puebla (Mexico); Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, 62210 Cuernavaca (Mexico); Ortiz, Yenni P. [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, 62210 Cuernavaca (Mexico); Kuhl, Ulrich [Université de Nice – Sophia Antipolis, Laboratoire de la Physique de la Matière Condensée, CNRS, Parc Valrose, 06108 Nice (France); Mortessagne, Fabrice, E-mail: fabrice.mortessagne@unice.fr [Université de Nice – Sophia Antipolis, Laboratoire de la Physique de la Matière Condensée, CNRS, Parc Valrose, 06108 Nice (France); Seligman, Thomas H. [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, 62210 Cuernavaca (Mexico); Centro Internacional de Ciencias, 62210 Cuernavaca (Mexico)

2017-01-05

A novel approach to investigate the electron transport of cis- and trans-polyacetylene chains in the single-electron approximation is presented by using microwave emulation measurements and tight-binding calculations. In the emulation we take into account the different electronic couplings due to the double bonds leading to coupled dimer chains. The relative coupling constants are adjusted by DFT calculations. For sufficiently long chains a transport band gap is observed if the double bonds are present, whereas for identical couplings no band gap opens. The band gap can be observed also in relatively short chains, if additional edge atoms are absent, which cause strong resonance peaks within the band gap. The experimental results are in agreement with our tight-binding calculations using the nonequilibrium Green's function method. The tight-binding calculations show that it is crucial to include third nearest neighbor couplings to obtain the gap in the cis-polyacetylene. - Highlights: • Electronic transport in individual polyacetylene chains is studied. • Microwave emulation experiments and tight-binding calculations agree well. • In long chains a band-gap opens due the dimerization of the chain. • In short chains edge atoms cause strong resonance peaks in the center of the band-gap.

Microwave emulations and tight-binding calculations of transport in polyacetylene

International Nuclear Information System (INIS)

Stegmann, Thomas; Franco-Villafañe, John A.; Ortiz, Yenni P.; Kuhl, Ulrich; Mortessagne, Fabrice; Seligman, Thomas H.

2017-01-01

A novel approach to investigate the electron transport of cis- and trans-polyacetylene chains in the single-electron approximation is presented by using microwave emulation measurements and tight-binding calculations. In the emulation we take into account the different electronic couplings due to the double bonds leading to coupled dimer chains. The relative coupling constants are adjusted by DFT calculations. For sufficiently long chains a transport band gap is observed if the double bonds are present, whereas for identical couplings no band gap opens. The band gap can be observed also in relatively short chains, if additional edge atoms are absent, which cause strong resonance peaks within the band gap. The experimental results are in agreement with our tight-binding calculations using the nonequilibrium Green's function method. The tight-binding calculations show that it is crucial to include third nearest neighbor couplings to obtain the gap in the cis-polyacetylene. - Highlights: • Electronic transport in individual polyacetylene chains is studied. • Microwave emulation experiments and tight-binding calculations agree well. • In long chains a band-gap opens due the dimerization of the chain. • In short chains edge atoms cause strong resonance peaks in the center of the band-gap.

LDA+U and tight-binding electronic structure of InN nanowires

Science.gov (United States)

Molina-Sánchez, A.; García-Cristóbal, A.; Cantarero, A.; Terentjevs, A.; Cicero, G.

2010-10-01

In this paper we employ a combined ab initio and tight-binding approach to obtain the electronic and optical properties of hydrogenated Indium nitride (InN) nanowires. We first discuss InN band structure for the wurtzite structure calculated at the LDA+U level and use this information to extract the parameters needed for an empirical tight-binging implementation. These parameters are then employed to calculate the electronic and optical properties of InN nanowires in a diameter range that would not be affordable by ab initio techniques. The reliability of the large nanowires results is assessed by explicitly comparing the electronic structure of a small diameter wire studied both at LDA+U and tight-binding level.

Active stretching for lower extremity muscle tightness in pediatric patients with lumbar spondylolysis.

Science.gov (United States)

Sato, Masahiro; Mase, Yasuyoshi; Sairyo, Koichi

2017-01-01

It was reported that hamstring muscle tightness may increase mechanical loading on the lumbar spine. Therefore, we attempt to decrease tightness in the leg muscles in pediatric patients. Forty-six pediatric patients with spondylolysis underwent rehabilitation. We applied active stretching to the hamstrings, quadriceps, and triceps surae. Tightness in each muscle was graded as good, fair, or poor. We educated each patient on how to perform active stretching at home. They were re-evaluated for muscle tightness 2 months later. Tightness at baseline and after 2 months was as follows: for the hamstrings, good in 3 patients, fair in 9, and poor in 34 and significant improved after 2 months (p<0.05), with improvement by least 1 grade seen in 86% of patients with fair or poor at baseline; for the quadriceps, 7, 3, and 30 patients had good, fair and poor, with significant improvements in 72% (p<0.05). For the triceps surae, 6, 3 and 10 patients had good, fair and poor, which improved significantly (p<0.05). Home-based active stretching was effective for relieving muscle tightness in the leg in a pediatric population. Adolescent athletes should perform such exercise to maintain flexibility and prevent lumbar disorders. J. Med. Invest. 64: 136-139, February, 2017.

Performance Improvement of Receivers Based on Ultra-Tight Integration in GNSS-Challenged Environments

Directory of Open Access Journals (Sweden)

Feng Qin

2013-12-01

Full Text Available Ultra-tight integration was first proposed by Abbott in 2003 with the purpose of integrating a global navigation satellite system (GNSS and an inertial navigation system (INS. This technology can improve the tracking performances of a receiver by reconfiguring the tracking loops in GNSS-challenged environments. In this paper, the models of all error sources known to date in the phase lock loops (PLLs of a standard receiver and an ultra-tightly integrated GNSS/INS receiver are built, respectively. Based on these models, the tracking performances of the two receivers are compared to verify the improvement due to the ultra-tight integration. Meanwhile, the PLL error distributions of the two receivers are also depicted to analyze the error changes of the tracking loops. These results show that the tracking error is significantly reduced in the ultra-tightly integrated GNSS/INS receiver since the receiver’s dynamics are estimated and compensated by an INS. Moreover, the mathematical relationship between the tracking performances of the ultra-tightly integrated GNSS/INS receiver and the quality of the selected inertial measurement unit (IMU is derived from the error models and proved by the error comparisons of four ultra-tightly integrated GNSS/INS receivers aided by different grade IMUs.

Tropical cyclone cloud‐top height and vertical temperature structure detection using GPS radio occultation measurements

DEFF Research Database (Denmark)

Biondi, Riccardo; Ho, Shu‐Peng; Randel, William

2013-01-01

The accurate determination of tropical cyclone (TC) cloud-top height and its vertical thermal structure using the GPS radio occultation (RO) technique is demonstrated in this study. Cloud-top heights are determined by using the bending angle anomaly and the temperature anomaly profiles during...

The “communication line” suggests occult posterior malleolar fracture associated with a spiral tibial shaft fracture

International Nuclear Information System (INIS)

Hou Zhiyong; Zhang Liping; Zhang Qi; Yao Shuangquan; Pan Jinshe; Irgit, Kaan; Zhang Yingze

2012-01-01

Objectives: To demonstrate radiographical characteristics of the relationship between distal spiral tibial shaft fractures and associated occult posterior malleolar fractures (PMF) that confirmed by CT and MRI. Materials and methods: X-rays for a ninety-six patients with spiral tibia fracture and associated PMF were reviewed. All patients additionally had an ankle CT. Patients with a negative CT scans underwent an ankle MRI. Radiographic observations included fracture location, characteristics, and a presence of a fracture line between the two injuries. Results: The spiral tibia fracture line was contiguous with PMF in 89 of 96 cases after evaluation with the CT and MRI. The line connecting the two injuries, which occurs between the medial inferior apex of the spiral tibia fracture line and the posterior superior apex of the PMF was identified as the “communication line”. In 47 of the 89 conjunction fractures, the “communication line” was detectable preoperatively and in 12 cases postoperatively by anteroposterior radiograph. By using the CT and MRI scans, we found that no “communication line” was present in only 7 cases. Conclusion: It is important to understand the nature of the association between distal spiral tibial shaft fractures and occult posterior malleolar fractures for optimal stabilization of the fracture and for appropriate rehabilitation. The “communication line” is a useful diagnostic clue for early recognition the occult PMF and alerts a closer evaluation of the lateral view and further CT examination.

Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs

Energy Technology Data Exchange (ETDEWEB)

Maria Cecilia Bravo

2006-06-30

This document reports progress of this research effort in identifying relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. These dependencies are investigated by identifying the main transport mechanisms at the pore scale that should affect fluids flow at the reservoir scale. A critical review of commercial reservoir simulators, used to predict tight sand gas reservoir, revealed that many are poor when used to model fluid flow through tight reservoirs. Conventional simulators ignore altogether or model incorrectly certain phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization. We studied the effect of Knudsen's number in Klinkenberg's equation and evaluated the effect of different flow regimes on Klinkenberg's parameter b. We developed a model capable of explaining the pressure dependence of this parameter that has been experimentally observed, but not explained in the conventional formalisms. We demonstrated the relevance of this, so far ignored effect, in tight sands reservoir modeling. A 2-D numerical simulator based on equations that capture the above mentioned phenomena was developed. Dynamic implications of new equations are comprehensively discussed in our work and their relative contribution to the flow rate is evaluated. We performed several simulation sensitivity studies that evidenced that, in general terms, our formalism should be implemented in order to get more reliable tight sands gas reservoirs' predictions.

MR imaging-guided sonography followed by fine-needle aspiration cytology in occult carcinoma of the breast

NARCIS (Netherlands)

A.I.M. Obdeijn (Inge-Marie); Brouwers-Kuyper, E.M.; M.M.A. Tilanus-Linthorst (Madeleine); T. Wiggers (Theo); M. Oudkerk (Matthijs)

2000-01-01

markdownabstractOBJECTIVE. In patients with axillary metastases as clinical evidence of possible occult breast cancer, a combined approach of MR imaging, sonography, and aspiration biopsy cytology was evaluated. SUBJECTS AND METHODS. Thirty-one women with metastatic adenocarcinoma in their

Inappropriate use of the faecal occult blood test in a university hospital in the Netherlands

NARCIS (Netherlands)

van Rijn, Anne F.; Stroobants, An K.; Deutekom, Marije; Lauppe, Corinne; Sturk, Auguste; Bossuyt, Patrick M. M.; Fockens, Paul; Dekker, Evelien

2012-01-01

Objectives Although all international guidelines state that there is no indication to perform a faecal occult blood test (FOBT) in symptomatic patients, we believe the test is frequently used as a diagnostic test. The objective of this study was to investigate whether the current guidelines for FOBT

Contraption and Prediction of Exhalation Tight Brownstone in Exhalation Cistern

OpenAIRE

XhingZhiwang, -; Xuchao, -

2012-01-01

The reservoir connate water saturation is high and gas wells generally produce water which seriously affects the productivity of gas wells in Xujiahe tight sandstone gas reservoirs in Sichuan Basin. Take the sixth formation for example, there are 39 wells producing water unequally in the 42 commissioning wells, and the excessive water production leads to the production of the gas well declining rapidly. Studying of the mechanism of water production in tight sandstone gas reservoirs and predic...

Radiographically Occult and Subtle Fractures: A Pictorial Review

International Nuclear Information System (INIS)

Jarraya, M.; Hayashi, D.; Roemer, F.W.; Crema, M.D.; Conlin, J.; Marra, M.D.; Guermazi, A.; Roemer, F.W.; Crema, M.D.; Diaz, L.; Conlin, J.; Jomaah, N.

2013-01-01

Radiographically occult and subtle fractures are a diagnostic challenge. They may be divided into (1) high energy trauma fracture, (2) fatigue fracture from cyclical and sustained mechanical stress, and (3) insufficiency fracture occurring in weakened bone (e.g., in osteoporosis and post radiotherapy). Independently of the cause, the initial radiographic examination can be negative either because the findings seem normal or are too subtle. Early detection of these fractures is crucial to explain the patients symptoms and prevent further complications. Advanced imaging tools such as computed tomography, magnetic resonance imaging, and scintigraphy are highly valuable in this context. Our aim is to raise the awareness of radiologists and clinicians in these cases by presenting illustrative cases and a discussion of the relevant literature.

Study on water leak-tightness of small leaks on a 1 inch cylinder valve

International Nuclear Information System (INIS)

Miyazawa, T.; Kasai, Y.; Inabe, N.; Aritomi, M.

2002-01-01

Practical thresholds for water leak-tightness of small leaks were determined by experimentation. Measurements for small leak samples were taken of air leakage rates and water leakage rates for identical leak samples in order to identify parameters that influence water leak-tightness threshold. Four types of leaks were evaluated: a fine wire inserted in an O-ring seal, a glass capillary tube, a stainless steel orifice, and a scratched valve stem on a 1 inch UF 6 cylinder valve. Experimental results demonstrated that the key parameter for water leak-tightness is the opening size of the leak hole. The maximum allowable hole size to achieve water leak-tightness ranged from 10 to 20 μm in diameter in this study. Experimental results with 1 inch UF 6 cylinder valve samples demonstrated that the acceptance criteria for preshipment leakage test, 1x10 -3 ref-cm 3 .s -1 , as prescribed in ANSI N14.5 is an appropriate value from the point of view of water leak-tightness for enriched UF 6 packages. The mechanism of water leak-tightness is plugging by tiny particles existing in water. The water used in experiments in this study contained far fewer particles than in water assumed to be encountered under accident conditions of transport. Therefore, the water leak-tightness threshold determined in this study is a conservative value in a practical evaluation. (author)

The Taiwanese-American occultation survey project stellar variability. III. Detection of 58 new variable stars

Energy Technology Data Exchange (ETDEWEB)

Ishioka, R.; Wang, S.-Y.; Zhang, Z.-W.; Lehner, M. J.; Cook, K. H.; King, S.-K.; Lee, T.; Marshall, S. L.; Schwamb, M. E.; Wang, J.-H.; Wen, C.-Y. [Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Alcock, C.; Protopapas, P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Axelrod, T. [Steward Observatory, 933 North Cherry Avenue, Room N204, Tucson, AZ 85721 (United States); Bianco, F. B. [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Byun, Y.-I. [Department of Astronomy and University Observatory, Yonsei University, 134 Shinchon, Seoul 120-749 (Korea, Republic of); Chen, W. P.; Ngeow, C.-C. [Institute of Astronomy, National Central University, No. 300, Jhongda Road, Jhongli City, Taoyuan County 320, Taiwan (China); Kim, D.-W. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Rice, J. A., E-mail: ishioka@asiaa.sinica.edu.tw [Department of Statistics, University of California Berkeley, 367 Evans Hall, Berkeley, CA 94720 (United States)

2014-04-01

The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg{sup 2} field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 δ Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.

Diagnosis of an isolated occult fracture of the posterior margin of the tibia with the SPECT/CT

International Nuclear Information System (INIS)

Bourdon, A.; Granier, P.; Mourad, M.

2007-01-01

We report the case of a 56-year-old woman, investigated for pains of the right ankle related to a trauma of an unspecified mechanism. The radiographic assessment was negative. The 99m Tc-HDP 3-phase bone scintigraphy highlighted, on the blood pool and the delayed images, a located lesion on the right ankle. The single photon emission computerized tomography guided by computerized tomography (SPECT-CT) showed a focused uptake on the posterior margin of the right tibia and a sharp lucent line within the tomo-scintigraphy spot of uptake. The diagnosis accepted was an isolated occult fracture of the posterior margin of the right tibia. The contribution of the 99m Tc-HDP 3-phase bone scintigraphy combined with the SPECT-CT in the diagnosis of the occult fractures is discussed. (N.C.)

Empirical tight-binding parameters for solid C60

International Nuclear Information System (INIS)

Tit, N.; Kumar, V.

1993-01-01

We present a tight-binding model for the electronic structure of C 60 using four (1s and 3p) orbitals per carbon atom. The model has been developed by fitting the tight-binding parameters to the ab-initio pseudopotential calculation of Troullier and Martins (Phys. Rev. B46, 1754 (1992)) in the face-centered cubic (Fm3-bar) phase. Following this, calculations of the energy bands and the density of electronic states have been carried out as a function of the lattice constant. Good agreement has been obtained with the observed lattice-constant dependence of T c using McMillan's formula. Furthermore, calculations of the electronic structure are presented in the simple cubic (Pa3-bar) phase. (author). 43 refs, 3 figs, 1 tab

Leak testing of bubble-tight dampers using tracer gas techniques

Energy Technology Data Exchange (ETDEWEB)

Lagus, P.L. [Lagus Applied Technology, Inc., San Diego, CA (United States); DuBois, L.J. [Commonwealth Edison, Zion, IL (United States); Fleming, K.M. [NCS Corporation, Columbus, OH (United States)] [and others

1995-02-01

Recently tracer gas techniques have been applied to the problem of measuring the leakage across an installed bubble-tight damper. A significant advantage of using a tracer gas technique is that quantitative leakage data are obtained under actual operating differential pressure conditions. Another advantage is that leakage data can be obtained using relatively simple test setups that utilize inexpensive materials without the need to tear ducts apart, fabricate expensive blank-off plates, and install test connections. Also, a tracer gas technique can be used to provide an accurate field evaluation of the performance of installed bubble-tight dampers on a periodic basis. Actual leakage flowrates were obtained at Zion Generating Station on four installed bubble-tight dampers using a tracer gas technique. Measured leakage rates ranged from 0.01 CFM to 21 CFM. After adjustment and subsequent retesting, the 21 CFM damper leakage was reduced to a leakage of 3.8 CFM. In light of the current regulatory climate and the interest in Control Room Habitability issues, imprecise estimates of critical air boundary leakage rates--such as through bubble-tight dampers--are not acceptable. These imprecise estimates can skew radioactive dose assessments as well as chemical contaminant exposure calculations. Using a tracer gas technique, the actual leakage rate can be determined. This knowledge eliminates a significant source of uncertainty in both radioactive dose and/or chemical exposure assessments.

Third nearest neighbor parameterized tight binding model for graphene nano-ribbons

Directory of Open Access Journals (Sweden)

Van-Truong Tran

2017-07-01

Full Text Available The existing tight binding models can very well reproduce the ab initio band structure of a 2D graphene sheet. For graphene nano-ribbons (GNRs, the current sets of tight binding parameters can successfully describe the semi-conducting behavior of all armchair GNRs. However, they are still failing in reproducing accurately the slope of the bands that is directly associated with the group velocity and the effective mass of electrons. In this work, both density functional theory and tight binding calculations were performed and a new set of tight binding parameters up to the third nearest neighbors including overlap terms is introduced. The results obtained with this model offer excellent agreement with the predictions of the density functional theory in most cases of ribbon structures, even in the high-energy region. Moreover, this set can induce electron-hole asymmetry as manifested in results from density functional theory. Relevant outcomes are also achieved for armchair ribbons of various widths as well as for zigzag structures, thus opening a route for multi-scale atomistic simulation of large systems that cannot be considered using density functional theory.

Leak tight sealants and joint details for concrete structure in RAPP

International Nuclear Information System (INIS)

Singha Roy, P.K.; Baste, M.S.

1975-01-01

Leak tightness may pertain to either air or water and in extreme cases each will require separate consideration based on general basic requirements. Leak-tight sealants against air pressure are required in the construction joints and around penetrations in the concrete containment structures. The containment structures should be able to withstand the maximum anticipated design pressure during the incident of a MCA with only minimal leakage (0.1% of bldg. volume per day in RAPP) which is mostly through these joints. Apart from proper joint design and preparation the sealant itself must have superb adhesion to the concrete surface and integrify throughout its service life to prevent any rupture or micro-cracks at any section of the joint. Leak tightness pertains to water tightness as well. A critical water-tight joint at the bottom dome of the prestressed concrete dousing tank at its junction with the 36 inches dia dousing water pipes constructed in RAPP-2, which should be able to withstand the water pressure, continuous submergence in the water of the tank and the longitudinal and lateral movement of the water pipes during opening and closure of the dousing valves, has been made and hydrostatically tested when not even the slight sweating was found. The construction and materials of the above joints and the sealant along with the properties and performance observed during testing/use are described. As the sealant used is an imported poly-sulphide caulking compound suggestions have also been made, which may be kept in mind while developing an Indian substitute. (author)

Continuous Shearlet Tight Frames

KAUST Repository

Grohs, Philipp

2010-10-22

Based on the shearlet transform we present a general construction of continuous tight frames for L2(ℝ2) from any sufficiently smooth function with anisotropic moments. This includes for example compactly supported systems, piecewise polynomial systems, or both. From our earlier results in Grohs (Technical report, KAUST, 2009) it follows that these systems enjoy the same desirable approximation properties for directional data as the previous bandlimited and very specific constructions due to Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009). We also show that the representation formulas we derive are in a sense optimal for the shearlet transform. © 2010 Springer Science+Business Media, LLC.

Economic evaluation on tight sandstone gas development projects in China and recommendation on fiscal and taxation support policies

OpenAIRE

Zhen Yang; Lingfeng Kong; Min Du; Chenhui Zhao

2016-01-01

China is rich in tight sandstone gas resources (“tight gas” for short). For example, the Sulige Gasfield in the Ordos Basin and the Upper Triassic Xujiahe Fm gas reservoir in the Sichuan Basin are typical tight gas reservoirs. In the past decade, tight gas reserve and production both have increased rapidly in China, but tight gas reservoirs are always managed as conventional gas reservoirs without effective fiscal, taxation and policy supports. The potential of sustainable tight gas productio...

Improving horizontal completions on heterogeneous tight shales

Energy Technology Data Exchange (ETDEWEB)

Suarez-Rivera, Roberto; Deenadayalu, Chaitanya; Chertov, Maxim; Novalo Hartanto, Ricardo; Gathogo, Patrick [Schlumberger (United States); Kunjir, Rahul [University of Utah (United States)

2011-07-01

Evaluation of the two formation characteristics conducive to economic well production is important when tight shale formation characterization and completion design are being considered. This paper presents the basic understanding required to improve the efficiency of horizontal completions in oil and gas producing shales. Guidelines are defined for effective perforation and fracturing to improve the efficiency and sustainability of horizontal completions using extensive laboratory characterization of mechanical properties on core, core/log integration and continuous mapping of these properties by logging-while-drilling (LWD) methods. The objective is to improve completion design efficiency. This is accomplished by suitable selection of perforation intervals based on an understanding of the relevant physical processes and rock characterization. Conditions at two reservoir regions, the near-wellbore and the far-wellbore, are outlined and are essential to completion design. From the study, it can be concluded that tight shales are strongly anisotropic and cannot be approximated using isotropic models.

Tight multilattices calculated by extended-cell cylindrization

Energy Technology Data Exchange (ETDEWEB)

Segev, M; Carmona, S

1983-01-01

Among the common features of advanced LWR concepts are the tightness of lattices and the symbiotic setting of different fuels. Such symbioses often come in the form of multilattices, whose numerically-repeated unit is a configuration of several pins, typically with one pin type at the center and pins of a second type surrounding the center pin. If this extended-cell (EC) unit is cylindricized, then a simple transport calculation of the unit will be possible. If the lattice of such units is tight, there is further an a priori reason to expect the cylindrization to introduce only a small distortion of the true neutron fluxes in the lattice. A strict numerical validation of the EC cylindrization approximation is impractical, but similar validations can be carried out for regular lattices, viewed as being made up of multicell units whose centers are moderators and whose peripheries are fuel pins. In these comparisons the EC cylindrization approximation gives good results.

Tight junction regulates epidermal calcium ion gradient and differentiation

International Nuclear Information System (INIS)

Kurasawa, Masumi; Maeda, Tetsuo; Oba, Ai; Yamamoto, Takuya; Sasaki, Hiroyuki

2011-01-01

Research highlights: → We disrupted epidermal tight junction barrier in reconstructed epidermis. → It altered Ca 2+ distribution and consequentially differentiation state as well. → Tight junction should affect epidermal homeostasis by maintaining Ca 2+ gradient. -- Abstract: It is well known that calcium ions (Ca 2+ ) induce keratinocyte differentiation. Ca 2+ distributes to form a vertical gradient that peaks at the stratum granulosum. It is thought that the stratum corneum (SC) forms the Ca 2+ gradient since it is considered the only permeability barrier in the skin. However, the epidermal tight junction (TJ) in the granulosum has recently been suggested to restrict molecular movement to assist the SC as a secondary barrier. The objective of this study was to clarify the contribution of the TJ to Ca 2+ gradient and epidermal differentiation in reconstructed human epidermis. When the epidermal TJ barrier was disrupted by sodium caprate treatment, Ca 2+ flux increased and the gradient changed in ion-capture cytochemistry images. Alterations of ultrastructures and proliferation/differentiation markers revealed that both hyperproliferation and precocious differentiation occurred regionally in the epidermis. These results suggest that the TJ plays a crucial role in maintaining epidermal homeostasis by controlling the Ca 2+ gradient.

Initial Experience of Tomosynthesis-Guided Vacuum-Assisted Biopsies of Tomosynthesis-Detected (2D Mammography and Ultrasound Occult) Architectural Distortions.

Science.gov (United States)

Patel, Bhavika K; Covington, Matthew; Pizzitola, Victor J; Lorans, Roxanne; Giurescu, Marina; Eversman, William; Lewin, John

2018-03-23

As experience and aptitude in digital breast tomosynthesis (DBT) have increased, radiologists are seeing more areas of architectural distortion (AD) on DBT images compared with standard 2D mammograms. The purpose of this study is to report our experience using tomosynthesis-guided vacuum-assisted biopsies (VABs) for ADs that were occult at 2D mammography and ultrasound and to analyze the positive predictive value for malignancy. We performed a retrospective review of 34 DBT-detected ADs that were occult at mammography and ultrasound. We found a positive predictive value of 26% (nine malignancies in 34 lesions). Eight of the malignancies were invasive and one was ductal carcinoma in situ. The invasive cancers were grade 1 (4/8; 50%), grade 2 (2/8; 25%), or grade 3 (1/8; 13%); information about one invasive cancer was not available. The mean size of the invasive cancers at pathologic examination was 7.5 mm (range, 6-30 mm). Tomosynthesis-guided VAB is a feasible method to sample ADs that are occult at 2D mammography and ultrasound. Tomosynthesis-guided VAB is a minimally invasive method that detected a significant number of carcinomas, most of which were grade 1 cancers. Further studies are needed.

Celestial shadows eclipses, transits, and occultations

CERN Document Server

Westfall, John

2015-01-01

Much of what is known about the universe comes from the study of celestial shadows—eclipses, transits, and occultations.  The most dramatic are total eclipses of the Sun, which constitute one of the most dramatic and awe-inspiring events of nature.  Though once a source of consternation or dread, solar eclipses now lead thousands of amateur astronomers and eclipse-chasers to travel to remote points on the globe to savor their beauty and the adrenaline-rush of experiencing totality, and were long the only source of information about the hauntingly beautiful chromosphere and corona of the Sun.   Long before Columbus, the curved shadow of the Earth on the Moon during a lunar eclipse revealed that we inhabit a round world. The rare and wonderful transits of Venus, which occur as it passes between the Earth and the Sun, inspired eighteenth century expeditions to measure the distance from the Earth to the Sun, while the recent transits of 2004 and 2012 were the most widely observed ever--and still produced re...

Subfracture insult to the human cadaver patellofemoral joint produces occult injury.

Science.gov (United States)

Atkinson, P J; Haut, R C

1995-11-01

The current criterion used by the automotive industry for injury to the lower extremity is based on visible bone fracture. Studies suggest, however, that chronic joint degeneration may occur after subfracture impact loads on the knee. We hypothesized that subfracture loading of the patellofemoral joint could result in previously undocumented microtrauma in areas of high contact pressure. In the current study, seven patellofemoral joints from human cadavers were subjected to impact with successively greater energy until visible fracture was noted. Transverse and comminuted fractures of the patella were noted at 6.7 kN of load. Approximately 45% of the impact energy then was delivered to the contralateral joint. Subfracture loads of 5.2 kN resulted in no gross bone fracture in five of seven specimens. Histological examination of the patellae horizontal split fracture in the subchondral bone, at the tidemark, or at the interface of calcified cartilage and subchondral bone. The trauma appeared predominantly on the lateral facet, adjacent to or directly beneath preexisting fibrillation of the articular surface. Surface fibrillation was noted in histological sections of control patellae (not subjected to impact loading), but occult damages were not observed. Although the mechanism of this occult trauma is unknown, similar damage has been shown to occur from direct shear loading. As these microcracks can potentiate a disease process in the joint, this study may suggest that the current criterion for injury, based on bone fracture alone, is not sufficiently conservative.

The occult nature of intramedullary spinal cord metastases from renal cell carcinoma.

LENUS (Irish Health Repository)

Zakaria, Zaitun

2012-01-01

Renal cell carcinomas (RCC) are characterised by a tendency to metastasise widely, often while remaining occult. Intramedullary spinal cord metastases (ISCM) from RCC may be the presenting feature of the disease or present at any time in the disease course. This case report discusses an ISCM from RCC which became manifested at the time of resection of the primary tumour. We review the literature published on ISCM from RCC from 1990 to date comparing disease characteristics and presentations.

Injuries and disorders among young ice skaters: relationship with generalized joint laxity and tightness

Directory of Open Access Journals (Sweden)

Okamura S

2014-08-01

Full Text Available Shinobu Okamura,1 Naoki Wada,1 Masayuki Tazawa,1 Makoto Sohmiya,1 Yoko Ibe,1 Toru Shimizu,1 Shigeru Usuda,2 Kenji Shirakura1 1Department of Rehabilitation Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan; 2Department of Physical Therapy, Gunma University School of Health Science, Maebashi, Gunma, Japan Abstract: This study retrospectively investigated 192 teenage speed and figure skaters with prior injuries documented by an athletes’ questionnaire, who underwent a physical examination to assess their muscle tightness and generalized joint laxity. In all athletes, the degree of muscle tightness and joint laxity were measured by a standardized physical examination. A descriptive report of the types of injuries showed a predominance of fractures, ligament injuries, enthesitis, and lower back pain. Approximately 5% of all skaters tested positive for tightness, while 25.8% of figure skaters and 15.2% of speed skaters had generalized ligamentous laxity. Statistical testing showed an association between ankle sprains and muscle tightness, and an association between knee enthesitis and muscle tightness in skating athletes. There was also an association between lower back pain and generalized joint laxity, which held true only for the male skaters. Keywords: sports injury, skating, junior athlete, tightness, joint laxity, medical checkup

Acute Zonal Occult Outer Retinopathy with Atypical Findings

Directory of Open Access Journals (Sweden)

Dimitrios Karagiannis

2014-01-01

Full Text Available Background. To report a case of acute zonal occult outer retinopathy (AZOOR with atypical electrophysiology findings. Case Presentation. A 23-year-old-female presented with visual acuity deterioration in her right eye accompanied by photopsia bilaterally. Corrected distance visual acuity at presentation was 20/50 in the right eye and 20/20 in the left eye. Fundus examination was unremarkable. Visual field (VF testing revealed a large scotoma. Pattern and full-field electroretinograms (PERG and ERG revealed macular involvement associated with generalized retinal dysfunction. Electrooculogram (EOG light rise and the Arden ratio were within normal limits bilaterally. The patient was diagnosed with AZOOR due to clinical findings, visual field defect, and ERG findings. Conclusion. This is a case of AZOOR with characteristic VF defects and clinical symptoms presenting with atypical EOG findings.

Adaptive tight frame based medical image reconstruction: a proof-of-concept study for computed tomography

International Nuclear Information System (INIS)

Zhou, Weifeng; Cai, Jian-Feng; Gao, Hao

2013-01-01

A popular approach for medical image reconstruction has been through the sparsity regularization, assuming the targeted image can be well approximated by sparse coefficients under some properly designed system. The wavelet tight frame is such a widely used system due to its capability for sparsely approximating piecewise-smooth functions, such as medical images. However, using a fixed system may not always be optimal for reconstructing a variety of diversified images. Recently, the method based on the adaptive over-complete dictionary that is specific to structures of the targeted images has demonstrated its superiority for image processing. This work is to develop the adaptive wavelet tight frame method image reconstruction. The proposed scheme first constructs the adaptive wavelet tight frame that is task specific, and then reconstructs the image of interest by solving an l 1 -regularized minimization problem using the constructed adaptive tight frame system. The proof-of-concept study is performed for computed tomography (CT), and the simulation results suggest that the adaptive tight frame method improves the reconstructed CT image quality from the traditional tight frame method. (paper)

Nonlinear Filtering with IMM Algorithm for Ultra-Tight GPS/INS Integration

Directory of Open Access Journals (Sweden)

Dah-Jing Jwo

2013-05-01

Full Text Available Abstract This paper conducts a performance evaluation for the ultra-tight integration of a Global positioning system (GPS and an inertial navigation system (INS, using nonlinear filtering approaches with an interacting multiple model (IMM algorithm. An ultra-tight GPS/INS architecture involves the integration of in-phase and quadrature components from the correlator of a GPS receiver with INS data. An unscented Kalman filter (UKF, which employs a set of sigma points by deterministic sampling, avoids the error caused by linearization as in an extended Kalman filter (EKF. Based on the filter structural adaptation for describing various dynamic behaviours, the IMM nonlinear filtering provides an alternative for designing the adaptive filter in the ultra-tight GPS/INS integration. The use of IMM enables tuning of an appropriate value for the process of noise covariance so as to maintain good estimation accuracy and tracking capability. Two examples are provided to illustrate the effectiveness of the design and demonstrate the effective improvement in navigation estimation accuracy. A performance comparison among various filtering methods for ultra-tight integration of GPS and INS is also presented. The IMM based nonlinear filtering approach demonstrates the effectiveness of the algorithm for improved positioning performance.

Equiangular tight frames and unistochastic matrices

Czech Academy of Sciences Publication Activity Database

Goyeneche, D.; Turek, Ondřej

2017-01-01

Roč. 50, č. 24 (2017), č. článku 245304. ISSN 1751-8113 R&D Projects: GA ČR GA17-01706S Institutional support: RVO:61389005 Keywords : equiangular tight frames * unistochastic matrices * SIC POVM Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 1.857, year: 2016

Surface Passivation in Empirical Tight Binding

OpenAIRE

He, Yu; Tan, Yaohua; Jiang, Zhengping; Povolotskyi, Michael; Klimeck, Gerhard; Kubis, Tillmann

2015-01-01

Empirical Tight Binding (TB) methods are widely used in atomistic device simulations. Existing TB methods to passivate dangling bonds fall into two categories: 1) Method that explicitly includes passivation atoms is limited to passivation with atoms and small molecules only. 2) Method that implicitly incorporates passivation does not distinguish passivation atom types. This work introduces an implicit passivation method that is applicable to any passivation scenario with appropriate parameter...

On tight multiparty Bell inequalities for many settings

OpenAIRE

Zukowski, Marek

2006-01-01

A derivation method is given which leads to a series of tight Bell inequalities for experiments involving N parties, with binary observables, and three possible local settings. The approach can be generalized to more settings. Ramifications are presented.

Detection of occult vertebral fractures by quantitative assessment of bone marrow attenuation values at MDCT

Energy Technology Data Exchange (ETDEWEB)

Henes, Frank Oliver, E-mail: f.henes@uke.de [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Groth, Michael [Department of Diagnostic and Interventional Neuroradiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Kramer, Harald [Department of Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 Munich (Germany); Department of Radiology, University of Wisconsin – Madison, Clinical Science Center, 600 Highland Avenue, Madison, WI 53792 (United States); Schaefer, Christian [Department of Trauma-, Hand- and Reconstructive Surgery, Spine Center, Center for Surgical Sciences, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg (Germany); Regier, Marc; Derlin, Thorsten; Adam, Gerhard; Bannas, Peter [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

2014-01-15

Objectives: To determine a cut-off value of Hounsfield attenuation units (HU) at multidetector computed tomography (MDCT) for valid and reliable detection of bone marrow oedema (BME) related to occult vertebral fractures. Methods: 36 patients underwent both MDCT and Magnetic Resonance Imaging (MRI) for evaluation of vertebral fractures of the thoracolumbar spine and were included in this retrospective study. Two readers independently assessed HU values at MDCT in a total of 196 vertebrae. Reliability was assessed by intraclass correlation coefficient and Bland–Altman analysis. For each patient we determined the vertebra with the lowest HU value and calculated the HU-difference to each other vertebral body. HU-differences were subjected to receiver operating characteristic (ROC) curve analysis to determine the diagnostic accuracy for detection of BME as determined by MRI, which served as the reference standard. Results of HU-measurements were compared with standard visual evaluation of MDCT. Results: HU measurements demonstrated a high interrater reliability (ICC = 0.984). ROC curve analysis (AUC = 0.978) exhibited an ideal cut-off value of 29.6 HU for detection of BME associated with vertebral fractures with an accuracy of 97.4% as compared to 93.4% accuracy of visual evaluation. Particularly, HU-measurements increased the sensitivity for detection of vertebral fractures from 78.0% to 92.7% due to the detection of 7 of 9 occult fractures that were missed by visual evaluation alone. Conclusions: Assessing bone marrow density by HU measurements using the cut-off of 29.6 HU is a valid and reliable tool for detection of BME related to occult vertebral fractures in MDCT. The introduced technique may allow more accurate treatment decisions and may make further diagnostic work-up with MRI unnecessary.

Detection of occult vertebral fractures by quantitative assessment of bone marrow attenuation values at MDCT

International Nuclear Information System (INIS)

Henes, Frank Oliver; Groth, Michael; Kramer, Harald; Schaefer, Christian; Regier, Marc; Derlin, Thorsten; Adam, Gerhard; Bannas, Peter

2014-01-01

Objectives: To determine a cut-off value of Hounsfield attenuation units (HU) at multidetector computed tomography (MDCT) for valid and reliable detection of bone marrow oedema (BME) related to occult vertebral fractures. Methods: 36 patients underwent both MDCT and Magnetic Resonance Imaging (MRI) for evaluation of vertebral fractures of the thoracolumbar spine and were included in this retrospective study. Two readers independently assessed HU values at MDCT in a total of 196 vertebrae. Reliability was assessed by intraclass correlation coefficient and Bland–Altman analysis. For each patient we determined the vertebra with the lowest HU value and calculated the HU-difference to each other vertebral body. HU-differences were subjected to receiver operating characteristic (ROC) curve analysis to determine the diagnostic accuracy for detection of BME as determined by MRI, which served as the reference standard. Results of HU-measurements were compared with standard visual evaluation of MDCT. Results: HU measurements demonstrated a high interrater reliability (ICC = 0.984). ROC curve analysis (AUC = 0.978) exhibited an ideal cut-off value of 29.6 HU for detection of BME associated with vertebral fractures with an accuracy of 97.4% as compared to 93.4% accuracy of visual evaluation. Particularly, HU-measurements increased the sensitivity for detection of vertebral fractures from 78.0% to 92.7% due to the detection of 7 of 9 occult fractures that were missed by visual evaluation alone. Conclusions: Assessing bone marrow density by HU measurements using the cut-off of 29.6 HU is a valid and reliable tool for detection of BME related to occult vertebral fractures in MDCT. The introduced technique may allow more accurate treatment decisions and may make further diagnostic work-up with MRI unnecessary

The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation.

Science.gov (United States)

Ortiz, J L; Santos-Sanz, P; Sicardy, B; Benedetti-Rossi, G; Bérard, D; Morales, N; Duffard, R; Braga-Ribas, F; Hopp, U; Ries, C; Nascimbeni, V; Marzari, F; Granata, V; Pál, A; Kiss, C; Pribulla, T; Komžík, R; Hornoch, K; Pravec, P; Bacci, P; Maestripieri, M; Nerli, L; Mazzei, L; Bachini, M; Martinelli, F; Succi, G; Ciabattari, F; Mikuz, H; Carbognani, A; Gaehrken, B; Mottola, S; Hellmich, S; Rommel, F L; Fernández-Valenzuela, E; Bagatin, A Campo; Cikota, S; Cikota, A; Lecacheux, J; Vieira-Martins, R; Camargo, J I B; Assafin, M; Colas, F; Behrend, R; Desmars, J; Meza, E; Alvarez-Candal, A; Beisker, W; Gomes-Junior, A R; Morgado, B E; Roques, F; Vachier, F; Berthier, J; Mueller, T G; Madiedo, J M; Unsalan, O; Sonbas, E; Karaman, N; Erece, O; Koseoglu, D T; Ozisik, T; Kalkan, S; Guney, Y; Niaei, M S; Satir, O; Yesilyaprak, C; Puskullu, C; Kabas, A; Demircan, O; Alikakos, J; Charmandaris, V; Leto, G; Ohlert, J; Christille, J M; Szakáts, R; Farkas, A Takácsné; Varga-Verebélyi, E; Marton, G; Marciniak, A; Bartczak, P; Santana-Ros, T; Butkiewicz-Bąk, M; Dudziński, G; Alí-Lagoa, V; Gazeas, K; Tzouganatos, L; Paschalis, N; Tsamis, V; Sánchez-Lavega, A; Pérez-Hoyos, S; Hueso, R; Guirado, J C; Peris, V; Iglesias-Marzoa, R

2017-10-11

Haumea-one of the four known trans-Neptunian dwarf planets-is a very elongated and rapidly rotating body. In contrast to other dwarf planets, its size, shape, albedo and density are not well constrained. The Centaur Chariklo was the first body other than a giant planet known to have a ring system, and the Centaur Chiron was later found to possess something similar to Chariklo's rings. Here we report observations from multiple Earth-based observatories of Haumea passing in front of a distant star (a multi-chord stellar occultation). Secondary events observed around the main body of Haumea are consistent with the presence of a ring with an opacity of 0.5, width of 70 kilometres and radius of about 2,287 kilometres. The ring is coplanar with both Haumea's equator and the orbit of its satellite Hi'iaka. The radius of the ring places it close to the 3:1 mean-motion resonance with Haumea's spin period-that is, Haumea rotates three times on its axis in the time that a ring particle completes one revolution. The occultation by the main body provides an instantaneous elliptical projected shape with axes of about 1,704 kilometres and 1,138 kilometres. Combined with rotational light curves, the occultation constrains the three-dimensional orientation of Haumea and its triaxial shape, which is inconsistent with a homogeneous body in hydrostatic equilibrium. Haumea's largest axis is at least 2,322 kilometres, larger than previously thought, implying an upper limit for its density of 1,885 kilograms per cubic metre and a geometric albedo of 0.51, both smaller than previous estimates. In addition, this estimate of the density of Haumea is closer to that of Pluto than are previous estimates, in line with expectations. No global nitrogen- or methane-dominated atmosphere was detected.

Application of radiotracer method for tightness control and leakage localization in industrial objects

International Nuclear Information System (INIS)

Kras, J; Walis, L.; Myczkowski, S.

2001-01-01

Application of 82 Br in the form of gaseous CH 3 Br for tightness control and leakage localization in large industrial apparatus as chemical reactors, columns, vessels, pipelines etc. has been presented. The tracer has been prepared at the place of measurements in a specially designed mobile chemical reactor. The paper presents different variants of the method convenient for: tightness control of underground pipelines, leakage control of technological objects working in chemical and petrochemical industry, tightness control of large metal vessels localized underground and on surface. The radiometric devices used in mentioned variants have ben performed as well

Extended Lagrangian formulation of charge-constrained tight-binding molecular dynamics.

Science.gov (United States)

Cawkwell, M J; Coe, J D; Yadav, S K; Liu, X-Y; Niklasson, A M N

2015-06-09

The extended Lagrangian Born-Oppenheimer molecular dynamics formalism [Niklasson, Phys. Rev. Lett., 2008, 100, 123004] has been applied to a tight-binding model under the constraint of local charge neutrality to yield microcanonical trajectories with both precise, long-term energy conservation and a reduced number of self-consistent field optimizations at each time step. The extended Lagrangian molecular dynamics formalism restores time reversal symmetry in the propagation of the electronic degrees of freedom, and it enables the efficient and accurate self-consistent optimization of the chemical potential and atomwise potential energy shifts in the on-site elements of the tight-binding Hamiltonian that are required when enforcing local charge neutrality. These capabilities are illustrated with microcanonical molecular dynamics simulations of a small metallic cluster using an sd-valent tight-binding model for titanium. The effects of weak dissipation on the propagation of the auxiliary degrees of freedom for the chemical potential and on-site Hamiltonian matrix elements that is used to counteract the accumulation of numerical noise during trajectories was also investigated.

Histogram Analysis of Apparent Diffusion Coefficients for Occult Tonsil Cancer in Patients with Cervical Nodal Metastasis from an Unknown Primary Site at Presentation.

Science.gov (United States)

Choi, Young Jun; Lee, Jeong Hyun; Kim, Hye Ok; Kim, Dae Yoon; Yoon, Ra Gyoung; Cho, So Hyun; Koh, Myeong Ju; Kim, Namkug; Kim, Sang Yoon; Baek, Jung Hwan

2016-01-01

To explore the added value of histogram analysis of apparent diffusion coefficient (ADC) values over magnetic resonance (MR) imaging and fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) for the detection of occult palatine tonsil squamous cell carcinoma (SCC) in patients with cervical nodal metastasis from a cancer of an unknown primary site. The institutional review board approved this retrospective study, and the requirement for informed consent was waived. Differences in the bimodal histogram parameters of the ADC values were assessed among occult palatine tonsil SCC (n = 19), overt palatine tonsil SCC (n = 20), and normal palatine tonsils (n = 20). One-way analysis of variance was used to analyze differences among the three groups. Receiver operating characteristic curve analysis was used to determine the best differentiating parameters. The increased sensitivity of histogram analysis over MR imaging and (18)F-FDG PET/CT for the detection of occult palatine tonsil SCC was evaluated as added value. Histogram analysis showed statistically significant differences in the mean, standard deviation, and 50th and 90th percentile ADC values among the three groups (P histogram analysis was 52.6% over MR imaging alone and 15.8% over combined conventional MR imaging and (18)F-FDG PET/CT. Adding ADC histogram analysis to conventional MR imaging can improve the detection sensitivity for occult palatine tonsil SCC in patients with a cervical nodal metastasis originating from a cancer of an unknown primary site. © RSNA, 2015.

‘Trick’, ‘Manipulation’ and ‘Farce’: Albert Moll’s Critique of Occultism

Science.gov (United States)

Wolffram, Heather

2012-01-01

In July 1925, the psychiatrist Albert Moll appeared before the district court in Berlin-Schöneberg charged with having defamed the medium Maria Vollhardt (alias Rudloff) in his 1924 book Der Spiritismus [Spiritism]. Supported by some of Berlin’s most prominent occultists, the plaintiff – the medium’s husband – argued that Moll’s use of terms such as ‘trick’, ‘manipulation’ and ‘farce’ in reference to Vollhardt’s phenomena had been libellous. In the three-part trial that followed, however, Moll’s putative affront to the medium – of which he was eventually acquitted – was overshadowed, on the one hand, by a debate over the scientific status of parapsychology, and on the other, by the question of who – parapsychologists, occultists, psychiatrists or jurists – was entitled to claim epistemic authority over the occult. This paper will use the Rudloff–Moll trial as a means of examining Moll’s critique of occultism, not only as it stood in the mid-1920s, but also as it had developed since the 1880s. It will also provide insight into the views of Germany’s occultists and parapsychologists, who argued that their legitimate bid for scientific credibility was hindered by Dunkelmänner [obscurantists] such as Albert Moll. PMID:23002297

When the bell tolls on Bell's palsy: finding occult malignancy in acute-onset facial paralysis.

Science.gov (United States)

Quesnel, Alicia M; Lindsay, Robin W; Hadlock, Tessa A

2010-01-01

This study reports 4 cases of occult parotid malignancy presenting with sudden-onset facial paralysis to demonstrate that failure to regain tone 6 months after onset distinguishes these patients from Bell's palsy patients with delayed recovery and to propose a diagnostic algorithm for this subset of patients. A case series of 4 patients with occult parotid malignancies presenting with acute-onset unilateral facial paralysis is reported. Initial imaging on all 4 patients did not demonstrate a parotid mass. Diagnostic delays ranged from 7 to 36 months from time of onset of facial paralysis to time of diagnosis of parotid malignancy. Additional physical examination findings, especially failure to regain tone, as well as properly protocolled radiologic studies reviewed with dedicated head and neck radiologists, were helpful in arriving at the diagnosis. An algorithm to minimize diagnostic delays in this subset of acute facial paralysis patients is presented. Careful attention to facial tone, in addition to movement, is important in the diagnostic evaluation of acute-onset facial paralysis. Copyright 2010 Elsevier Inc. All rights reserved.

Electron number density profiles derived from radio occultation on the CASSIOPE spacecraft

DEFF Research Database (Denmark)

Shume, E. B.; Vergados, P.; Komjathy, A.

2017-01-01

This paper presents electron number density profiles derived from high resolution Global Positioning System (GPS) radio occultation (RO) observations performed using the Enhanced Polar Outflow Probe (e-POP) payload on the high inclination CAScade, Smallsat and IOnospheric Polar Explorer (CASSIOPE...... good agreement with density profiles estimated from ionosonde data, measured over nearby stations to the latitude and longitude of the RO tangent points, (2) in good agreement with density profiles inferred from GPS RO measured by the Constellation Observing System for Meteorology, Ionosphere...

Leakage detecting method and device for water tight vessel of wet-type container apparatus

International Nuclear Information System (INIS)

Tanaka, Yoshimi.

1995-01-01

The present invention provides a method of and a device for detecting leakage of a water tight vessel of a wet-type container apparatus for containing a reactor pressure vessel while immersing it water in a reactor container. Namely, in the wet-type container apparatus, the periphery of the pressure vessel is coated with a heat insulation material and the periphery of the heat insulation material is coated with a water tight vessel. The water tight vessel is immersed under water in the reactor container. As a method of detecting leakage of the wet-type container apparatus, gases mixed with helium are supplied into the water tight vessel at a pressure higher than the inner pressure of the reactor container at a lowest position of the reactor pressure vessel. A water level in the reactor container is determined so as to form a space at the top portion of the inside of the reactor container. The helium at the top portion is detected to monitor the leakage of the water tight vessel. With such procedures, even if the water tight vessel is ruptured at any position, helium mixed to the gases is released to water in the reactor container and rise up to the top space and detected by a helium leakage detection device. (I.S.)

ULTRA-WIDE-FIELD FUNDUS AUTOFLUORESCENCE FINDINGS IN PATIENTS WITH ACUTE ZONAL OCCULT OUTER RETINOPATHY.

Science.gov (United States)

Shifera, Amde Selassie; Pennesi, Mark E; Yang, Paul; Lin, Phoebe

2017-06-01

To determine whether ultra-wide-field fundus autofluorescence (UWFFAF) findings in acute zonal occult outer retinopathy correlated well with perimetry, optical coherence tomography, and electroretinography findings. Retrospective observational study on 16 eyes of 10 subjects with AZOOR seen at a single referral center from October 2012 to March 2015 who had UWFFAF performed. Chi-square analysis was performed to compare categorical variables, and Mann-Whitney U test used for comparisons of nonparametric continuous variables. All eyes examined within 3 months of symptom onset (five of the five eyes) had diffusely hyperautofluorescent areas on UWFFAF. The remaining eyes contained hypoautofluorescent lesions with hyperautofluorescent borders. In 11/16 (68.8%) eyes, UWFFAF showed the full extent of lesions that would not have been possible with standard fundus autofluorescence centered on the fovea. There were 3 patterns of spread: centrifugal spread (7/16, 43.8%), centripetal spread (5/16, 31.3%), and centrifugal + centripetal spread (4/16, 25.0%). The UWFFAF lesions corresponded well with perimetric, optical coherence tomography, and electroretinography abnormalities. The UWFFAF along with optical coherence tomography can be useful in the evaluation and monitoring of acute zonal occult outer retinopathy patients.

Occult lung malignancy presenting with finger pain: a case report

Directory of Open Access Journals (Sweden)

Embley Matthew A

2008-12-01

Full Text Available Abstract Introduction Lung cancer is currently one of the most common malignancies in the world. Early detection is an important prognostic factor. Unfortunately, initial symptoms may be vague and a substantial proportion of cases present with the effects of metastases. Case presentation We discuss a case of occult lung malignancy in a 61-year-old man. The only symptom at presentation was pain in the right ring finger due to metastasis from the lung primary. Conclusion This case highlights the need for vigilance when a patient presents with unusual or unexplained symptoms, especially if they have known risk factors for cancer.

Astrology and other occult sciences in seventeenth-century New Spain.

Science.gov (United States)

Avalos, Ana

2006-01-01

This article focuses on the relationship and mutual influence of astrology and other so-called occult sciences within the context of seventeenth-century New Spain. By presenting some case studies of inquisitorial trials against astrologers, it explores the interrelation between astrological and physiognomical ideas and practices in order to shed some light on the moral dimension of these natural philosophical fields of knowledge. During the early modern period, both astrology and physiognomy were regarded as tools for self-understanding and the understanding of others by means of interpretation of natural signs. Thus their history is key for understanding the shaping of the boundaries between the natural and the moral realms.

Identification of MarvelD3 as a tight junction-associated transmembrane protein of the occludin family

Directory of Open Access Journals (Sweden)

Balda Maria S

2009-12-01

Full Text Available Abstract Background Tight junctions are an intercellular adhesion complex of epithelial and endothelial cells, and form a paracellular barrier that restricts the diffusion of solutes on the basis of size and charge. Tight junctions are formed by multiprotein complexes containing cytosolic and transmembrane proteins. How these components work together to form functional tight junctions is still not well understood and will require a complete understanding of the molecular composition of the junction. Results Here we identify a new transmembrane component of tight junctions: MarvelD3, a four-span transmembrane protein. Its predicted transmembrane helices form a Marvel (MAL and related proteins for vesicle traffic and membrane link domain, a structural motif originally discovered in proteins involved in membrane apposition and fusion events, such as the tight junction proteins occludin and tricellulin. In mammals, MarvelD3 is expressed as two alternatively spliced isoforms. Both isoforms exhibit a broad tissue distribution and are expressed by different types of epithelial as well as endothelial cells. MarvelD3 co-localises with occludin at tight junctions in intestinal and corneal epithelial cells. RNA interference experiments in Caco-2 cells indicate that normal MarvelD3 expression is not required for the formation of functional tight junctions but depletion results in monolayers with increased transepithelial electrical resistance. Conclusions Our data indicate that MarvelD3 is a third member of the tight junction-associated occludin family of transmembrane proteins. Similar to occludin, normal expression of MarvelD3 is not essential for the formation of functional tight junctions. However, MarvelD3 functions as a determinant of epithelial paracellular permeability properties.

Occult abnormal pregnancies after first post-embryo transfer serum beta-human chorionic gonadotropin levels of 1.0-5.0 mIU/mL.

Science.gov (United States)

Maslow, Bat-Sheva L; Bartolucci, Alison; Sueldo, Carolina; Engmann, Lawrence; Benadiva, Claudio; Nulsen, John C

2016-04-01

To assess the occult pregnancy rate after "negative" first post-embryo transfer (ET) serum β-hCG results. Two-part retrospective cohort study and nested case series. University-based fertility center. A total of 1,571 negative first post-ET serum β-hCG results were included in the study; 1,326 results (primary cohort, June 2009-December 2013) were initially reported as <5 mIU/mL and 245 results (secondary cohort, January 2014-March 2015) were reported as discrete values from 1.0 to 5.0 mIU/mL. None. Rates of occult pregnancy, ectopic pregnancy, and complications after negative first post-ET serum β-hCG results. A total of 88.8% (1,178/1,326) of the negative first post-ET results reported as <5 were actually <1.0 mIU/mL. Occult pregnancy was incidentally identified in 1.2% (12/1,041) of subjects with follow-up. Six had ectopic pregnancies, and seven experienced serious complications; 11 (91.7%) of the 12 occult pregnancies had a first post-ET serum β-hCG level of 1.0-5.0 mIU/mL and 1 (8.3%) <1.0 mIU/mL. All pregnancies with serious complications had initial β-hCG levels of 1.0-5.0 mIU/mL. Of the 245 results reported as discreet values, occult pregnancies were diagnosed in 5.5% (9/163) of subjects with follow-up. One had an ectopic pregnancy, which was treated with methotrexate. There were no serious complications in the secondary cohort. The majority of negative first post-ET serum β-hCG levels are <1.0 mIU/mL. Results from 1.0 to 5.0 mIU/mL may fail to exclude abnormal pregnancy and are associated with poor outcomes compared with β-hCG levels <1.0 mIU/mL. Serial serum β-hCG may be warranted in this population. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Tightness of the thermal envelope of office and educational buildings; Klimaskaermens taethed i kontor- og undervisningsbygninger

Energy Technology Data Exchange (ETDEWEB)

Bergsoee, N.C. (SBi, Aalborg (Denmark)); Radisch, N.H.; Nickel, J.; Treldal, J. (Ramboell Danmark A/S, Koebenhavn (Denmark)); Bundesen, E.W.; Nielsen, Carsten (DanEjendomme, Hellerup (Denmark))

2011-07-01

In 2006 tightening of the energy regulations in the Danish Building Regulations were introduced including requirements regarding the tightness of the building envelope. The requirements are, with minor changes, continued in the current Building Regulations, BR10. During the past few years experience has been gained regarding both the actual execution of air tightness measurements and solutions that will lead to more air tight building envelopes. Experiences, however, are primarily related to single family houses. The report presents results of measurements in large buildings and discusses reasons for lack of knowledge and experience on the tightness of the building envelope in large buildings. Apparently, there is a need for dissemination of knowledge on the importance of a tight building envelope both in terms of energy consumption and indoor climate and in terms of the difficulties and costs associated with repairing leaks in a completed envelope. Air tightness must be brought into focus at an early stage in the planning process, and during the construction phase air tightness measurements should be performed, e.g. on facade sections or in parts of the building. The project team has attended a number of measurements in large buildings and further gained access to results of a large number of measurements. In summary, the results show that it is possible to achieve the required tightness, and in most buildings the results are better than the requirement of a maximum of 1.5 l/s per m{sub 2}. (Author)

Expression of Tight Junction Protein Claudin-1 in Human Crescentic Glomerulonephritis

Directory of Open Access Journals (Sweden)

Ryo Koda

2014-01-01

Full Text Available The origin of crescent forming cells in human glomerulonephritis (GN remains unknown. Some animal studies demonstrated that parietal epithelial cells of Bowman’s capsule (PECs were the main component of proliferating cells and PEC-specific tight junction protein claudin-1 was expressed in crescentic lesions. We investigated the expression of claudin-1 in human GN. Immunohistochemistry for claudin-1 was performed on 17 kidney biopsy samples with crescent formation. Colocalization of claudin-1 with intracellular tight junction protein ZO-1 was also evaluated by immunofluorescence double staining. Claudin-1 is expressed mainly at the cell to cell contact site of proliferating cells in cellular crescentic lesions in patients with these forms of human GN. Small numbers of crescent forming cells showed extrajunctional localization of claudin-1. Colocalization of claudin-1 with ZO-1 was found at cell to cell contact sites of adjacent proliferating cells. In control samples, staining of claudin-1 was positive in PECs, but not in podocytes. Our findings suggest that claudin-1 contributes to crescent formation as a component of the tight junction protein complex that includes ZO-1. Co-localization of claudin-1 with ZO-1 implies the formation of functional tight junction complexes in crescentic lesions to prevent the interstitial damage caused by penetration of filtered molecules from Bowman’s space.

Absolute tightness: the chemists hesitate to invest

International Nuclear Information System (INIS)

Anon.

1996-01-01

The safety requirements of industries as nuclear plants and the strengthening of regulations in the field of environment (more particularly those related to volatile organic compounds) have lead the manufacturers to build absolute tightness pumps. But these equipments do not answer all the problems and represent a high investment cost. In consequence, the chemists hesitate to invest. (O.L.)

Critical heat flux experiments in tight lattice core

Energy Technology Data Exchange (ETDEWEB)

Kureta, Masatoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-12-01

Fuel rods of the Reduced-Moderation Water Reactor (RMWR) are so designed to be in tight lattices as to reduce moderation and achieve higher conversion ratio. As for the BWR type reactor coolant flow rate is reduced small compared with the existing BWR, so average void fraction comes to be langer. In order to evaluate thermo hydraulic characteristics of designed cores, critical heat flux experiments in tight lattice core have been conducted using simulated high pressure coolant loops for both the PWR and BWR seven fuel rod bundles. Experimental data on critical heat flux for full bundles have been accumulated and applied to assess the critical power of designed cores using existing codes. Evaluated results are conservative enough to satisfy the limiting condition. Further experiments on axial power distribution effects and 37 fuel rod bundle tests will be performed to validate thermohydraulic characteristics of designed cores. (T. Tanaka)

Critical heat flux experiments in tight lattice core

International Nuclear Information System (INIS)

Kureta, Masatoshi

2002-01-01

Fuel rods of the Reduced-Moderation Water Reactor (RMWR) are so designed to be in tight lattices as to reduce moderation and achieve higher conversion ratio. As for the BWR type reactor coolant flow rate is reduced small compared with the existing BWR, so average void fraction comes to be langer. In order to evaluate thermo hydraulic characteristics of designed cores, critical heat flux experiments in tight lattice core have been conducted using simulated high pressure coolant loops for both the PWR and BWR seven fuel rod bundles. Experimental data on critical heat flux for full bundles have been accumulated and applied to assess the critical power of designed cores using existing codes. Evaluated results are conservative enough to satisfy the limiting condition. Further experiments on axial power distribution effects and 37 fuel rod bundle tests will be performed to validate thermohydraulic characteristics of designed cores. (T. Tanaka)

Utility of the serum C-reactive protein for detection of occult bacterial infection in children.

Science.gov (United States)

Isaacman, Daniel J; Burke, Bonnie L

2002-09-01

To assess the utility of serum C-reactive protein (CRP) as a screen for occult bacterial infection in children. Febrile children ages 3 to 36 months who visited an urban children's hospital emergency department and received a complete blood cell count and blood culture as part of their evaluation were prospectively enrolled from February 2, 2000, through May 30, 2001. Informed consent was obtained for the withdrawal of an additional 1-mL aliquot of blood for use in CRP evaluation. Logistic regression and receiver operator characteristic (ROC) curves were modeled for each predictor to identify optimal test values, and were compared using likelihood ratio tests. Two hundred fifty-six patients were included in the analysis, with a median age of 15.3 months (range, 3.1-35.2 months) and median temperature at triage 40.0 degrees C (range, 39.0 degrees C-41.3 degrees C). Twenty-nine (11.3%) cases of occult bacterial infection (OBI) were identified, including 17 cases of pneumonia, 9 cases of urinary tract infection, and 3 cases of bacteremia. The median white blood cell count in this data set was 12.9 x 10(3)/ micro L [corrected] (range, 3.6-39.1 x10(3)/ micro L) [corrected], the median absolute neutrophil count (ANC) was 7.12 x 10(3)/L [corrected] (range, 0.56-28.16 x10(3)/L) [corrected], and the median CRP level was 1.7 mg/dL (range, 0.2-43.3 mg/dL). The optimal cut-off point for CRP in this data set (4.4 mg/dL) achieved a sensitivity of 63% and a specificity of 81% for detection of OBI in this population. Comparing models using cut-off values from individual laboratory predictors (ANC, white blood cell count, and CRP) that maximized sensitivity and specificity revealed that a model using an ANC of 10.6 x10(3)/L [corrected] (sensitivity, 69%; specificity, 79%) was the best predictive model. Adding CRP to the model insignificantly increased sensitivity to 79%, while significantly decreasing specificity to 50%. Active monitoring of emergency department blood cultures

Economic evaluation on tight sandstone gas development projects in China and recommendation on fiscal and taxation support policies

Directory of Open Access Journals (Sweden)

Zhen Yang

2016-11-01

Full Text Available China is rich in tight sandstone gas resources (“tight gas” for short. For example, the Sulige Gasfield in the Ordos Basin and the Upper Triassic Xujiahe Fm gas reservoir in the Sichuan Basin are typical tight gas reservoirs. In the past decade, tight gas reserve and production both have increased rapidly in China, but tight gas reservoirs are always managed as conventional gas reservoirs without effective fiscal, taxation and policy supports. The potential of sustainable tight gas production increase is obviously restricted. The tight gas development projects represented by the Sulige Gasfield have failed to make profit for a long period, and especially tight gas production has presented a slight decline since 2015. In this paper, a new economic evaluation method was proposed for tight gas development projects. The new method was designed to verify the key parameters (e.g. production decline rate and single-well economic service life depending on tight gas development and production characteristics, and perform the depreciation by using the production method. Furthermore, the possibility that the operation cost may rise due to pressure-boosting production and intermittent opening of gas wells is considered. The method was used for the tight gas development project of Sulige Gasfield, showing that its profit level is much lower than the enterprise's cost level of capital. In order to support a sustainable development of tight gas industry in China, it is recommended that relevant authorities issue value-added tax (VAT refund policy as soon as possible. It is necessary to restore the non-resident gas gate price of the provinces where tight gas is produced to the fair and reasonable level in addition to the fiscal subsidy of CNY0.24/m3, or offer the fiscal subsidy of CNY0.32/m3 directly based on the on-going gate price. With these support policies, tax income is expected to rise directly, fiscal expenditure will not increase, and gas

ARTHROSCOPIC TREATMENT OF ACROMIOCLAVICULAR JOINT DISLOCATION BY TIGHT ROPE TECHNIQUE (ARTHREX®)

Science.gov (United States)

GÓmez Vieira, Luis Alfredo; Visco, Adalberto; Daneu Fernandes, Luis Filipe; GÓmez Cordero, Nicolas Gerardo

2015-01-01

Presenting the arthroscopic treatment by Tight Rope - Arthrex® system for acute acromioclavicular dislocation and to evaluate results obtained with this procedure. Methods: Between August 2006 and May 2007, 10 shoulders of 10 patients with acute acromioclavicular dislocation were submitted to arthroscopic repair using the Tight Rope - Arthrex® system. Minimum follow-up was 12 months, with a mean of 15 months. Age ranged from 26 to 42, mean 34 years. All patients were male. Radiology evaluation was made by trauma series x-ray. The patients were assisted in the first month weekly and after three months after the procedure. Clinical evaluation was based on the University of California at Los Angeles (UCLA) criteria. Results: All patients were satisfied after the arthroscopic procedure and the mean UCLA score was 32,5. Conclusion: The arthroscopic treatment by Tight Rope – Arthrex® system for acute acromioclavicular dislocation showed to be an efficient technique. PMID:26998453

Loosen up? Cultural tightness and national entrepreneurial activity

NARCIS (Netherlands)

Harms, Rainer; Groen, Arend J.

The level of entrepreneurship between countries differs consistently. A source of this variance lies in national culture differences. Recently, the cultural dimension “tightness” has been introduced in the literature. Tightness refers to the degree to which a nation has strong norms and a low

Trapping of Rydberg atoms in tight magnetic microtraps

NARCIS (Netherlands)

Boetes, A.Q.G.; Skannrup, R.V.; Naber, J.; Kokkelmans, S.J.J.M.F.; Spreeuw, R.J.C.

2018-01-01

We explore the possibility to trap Rydberg atoms in tightly confining magnetic microtraps. The trapping frequencies for Rydberg atoms are expected to be influenced strongly by magnetic-field gradients. We show that there are regimes where Rydberg atoms can be trapped. Moreover, we show that

Polarimetric mountain based radio-occultation for rain detection: The ROHP-PAZ ground campaign

Science.gov (United States)

Padulles, Ramon; Cardellach, Estel; Tomas, Sergio; de la Torre, Manuel; Turk, Joe

2014-05-01

The Radio Occultation and Heavy Precipitation experiment aboard the PAZ Low Earth Orbiter (ROHP-PAZ) is a mission of opportunity: The Spanish Ministry of Science and Innovation (MICINN) approved in 2009 a proposal to include a polarimetric Global Navigation Satellite System (GNSS) Radio-Occultation (RO) payload on board of the Spanish Earth Observation satellite PAZ. This will be a new technique that has never been tested before, that aims to improve the knowledge of precipitation through simultaneous thermodynamic and vertical rain profiles. Prior to the launch of the satellite, expected for 2014, a ground experimental campaign is being conducted with the goal of starting the process of identifying and understanding all the factors that might affect the polarimetric RO observables. The campaign is being carried out at the top of Puig Sesolles, a 1667m peak in the Natural Park of Montseny (41º46'24 N, 2º26'17 E), 50 km N-NE from Barcelona, with clear views over the horizon to the South (East to West) direction, an area in which intense precipitation events tend to occur a few times per year. The campaign uses a ICE-CSIC/IEEC's GOLD-RTR open-loop receiver initially designed for collecting GNSS signals reflected off the sea surface. The receiver has been adjusted to track occulting GNSS radio-links. A double polarization (H and V) GNSS antenna has been designed and manufactured by the Polytechnic University of Barcelona (UPC) team for this particular ground-based experiment. The antenna is a phase-array made of 7 elements, each of them being a square patch built using a Rogers 4003 substrate, and symmetrically fed by four probes. It provides a pattern of 12.9 dB peak gain, 45 degrees half-power beam-width, and <-35 dB cross-polar isolation at the peak (better than -30 dB in the main lobe). The preliminary results show that not only precipitation, but also other factors are affecting the GNSS signal, wich means that the polarimetric signal is richer than expected

Spatial irregularities in Jupiter's upper ionosphere observed by Voyager radio occultations

Science.gov (United States)

Hinson, D. P.; Tyler, G. L.

1982-01-01

Radio scintillations (at 3.6 and 13 cm) produced by scattering from ionospheric irregularities during the Voyager occultations are interpreted using a weak-scattering theory. Least squares solutions for ionospheric parameters derived from the observed fluctuation spectra yield estimates of (1) the axial ratio, (2) angular orientation of the anisotropic irregularities, (3) the power law exponent of the spatial spectrum of irregularities, and (4) the magnitude of the spatial variations in electron density. It is shown that the measured angular orientation of the anisotropic irregularities indicates magnetic field direction and may provide a basis for refining Jovian magnetic field models.

The occultation of Epsilon Geminorum by Mars - Analysis of McDonald data. [turbulent scintillation in light curves

Science.gov (United States)

Africano, J.; De Vaucouleurs, G.; Evans, D. S.; Finkel, B. E.; Nather, R. E.; Palm, C.; Silverberg, E.; Wiant, J.; Hubbard, W. B.; Jokipii, J. R.

1977-01-01

An analysis of observations of the occultation of Epsilon Gem by Mars on April 8, 1976, is presented. The data were obtained by three neighboring telescopes at McDonald Observatory. Intensity fluctuations on time scales of the order of 100 ms were observed simultaneously at the three telescopes. As the observations compare well with predictions of turbulent scintillation theory, it is concluded that such fluctuations were probably largely the effect of stellar scintillations in the Martian atmosphere. The stellar diameter is included as a parameter in the theory but in a way which differs from previously published interpretations of occultations of extended sources by planetary atmospheres. Scintillations govern the experimental uncertainty in the deduction of the scale height of the high Martian atmosphere. A density scale height of 9.9 + or - 2.5 km is obtained at an altitude of 74 + or - 8 km above the mean surface. For CO 2 gas, this result corresponds to a temperature of 190 + or - 50 K.

A rare case of occult abdominal tuberculosis with Poncet′s disease mimicking Adult onset Still′s disease

Directory of Open Access Journals (Sweden)

Isha Sood

2015-01-01

Full Text Available A 50-year-old female presented with fever, symmetrical arthralgias, rash, painful oral ulcerations and alopecia since 8 weeks. Examination showed mild hepatospleenomegaly. Investigations revealed leucocytosis, neutrophilia, elevated sedimentation rate and raised ferritin levels (3850 ng/ml. Computerized tomography (CT abdomen showed hepatospleenomegaly, mild ascitis and mild bilateral pleural-effusion. After ruling out occult infections, tuberculosis, malignancies and autoimmune diseases by appropriate investigations, and due to raised ferritin levels, adult onset stills disease (AOSD was diagnosed. Patient responded to oral steroids initially, but after 7 days developed severe abdominal pain. Repeat CT showed multiple enlarged, necrotic and matted retroperitoneal lymph nodes with caseating granuloma on histopathology suggesting tuberculosis. Patient was given four-drug anti-tubercular treatment and she improved. Thus our patient of occult abdominal tuberculosis with reactive arthritis (Poncet′s disease presented with hyperferritinemia mimicking AOSD. We postulate that extreme hyperferritinemia can be seen in tuberculosis and tuberculosis must be conclusively ruled out before diagnosing AOSD in tropics.

Numerical simulation of flow behavior in tight lattice rod bundle

International Nuclear Information System (INIS)

Yu Yiqi; Yang Yanhua; Gu Hanyang; Cheng Xu; Song Xiaoming; Wang Xiaojun

2009-01-01

The Numerical investigation is performed on the air turbulent flow in triangular rod bundle array. Based on the experimental data, the eddy viscosity turbulent model and the Reynold stress turbulent model are evaluated to simulate the flow behavior in the tight lattice. The results show that SSG Reynolds Stress Model has shown superior predictive performance than other Reynolds-stress models, which indicates that the simulation of the anisotropy of the turbulence is significant in the tight lattice. The result with different Reynolds number and geometry shows that the magnitude of the secondary flow is almost independent of the Reynolds number, but it increases with the decrease of the P/D. (authors)

Ultra-Tightly Coupled GNSS/INS for small UAVs

DEFF Research Database (Denmark)

Olesen, Daniel; Jakobsen, Jakob; Knudsen, Per

2017-01-01

This paper describes an ultra-tight integration of a Global Navigation Satellite System ( GNSS) receiver and an Inertial Navigation System ( INS) for small Unmanned Aerial Vehicles ( UAVs). The system is based on a low-cost and low-weight GNSS Intermediate Frequency ( IF) sampler which has been...

Outcome of tight versus standard glycemic control in coronary artery bypass patients

International Nuclear Information System (INIS)

Subhani, H.

2012-01-01

Objectives: To compare the outcome of tight versus standard glycemic control and its impact on post operative morbidity and short term mortality in patients undergoing Coronary Artery Bypass Grafting (CA-BG). Patients and Methods: A prospective surveillance of 124 patients undergoing isolated CABG surgery (on pump) was included in the study, 62 patients in each group were randomly assigned to tight and standard glucose control group. The main exposure was insulin in respect to level of blood glucose and the primary outcome measures were Sternotomy wound infection, Leg wound infection and new Myocardial Infarction. Surgical Site infection was assessed on a daily basis during the patient's stay in the Department of Cardio-thoracic Surgery, Sheikh Zayed Hospital, Lahore or within 30 days of operation prompting the patient to return to the hospital. Chi-square test or test was used to identify the significance of various short term morbidities and mortality. Results: In this study, 12 patients in the standard group and 4 patients in the tightly controlled group developed Sternal wound infection (p value 0.046). Similarly, 9 versus 2 patients in the standard and tight group respectively developed Leg wound infection (p-value 0.035). Test of proportion was applied and it was found that there was significant difference in the pro-portion of infection in the two groups (p value 0.05). However, there were no significant differences in other morbidities and the short term mortality. Conclusion: Study confirmed that tight glucose con-trol post operatively in CABG patient's results in reduced sternal and leg wound infection rates; however, there was no effect on other morbidities and short term mortality. (author)

Small Spacecraft Constellation Concept for Mars Atmospheric Radio Occultations

Science.gov (United States)

Asmar, S. W.; Mannucci, A. J.; Ao, C. O.; Kobayashi, M. M.; Lazio, J.; Marinan, A.; Massone, G.; McCandless, S. E.; Preston, R. A.; Seubert, J.; Williamson, W.

2017-12-01

First demonstrated in 1965 when Mariner IV flew by Mars and determined the salient features of its atmosphere, radio occultation experiments have been carried out on numerous planetary missions with great discoveries. These experiments utilize the now classic configuration of a signal from a single planetary spacecraft to Earth receiving stations, where the science data are acquired. The Earth science community advanced the technique to utilizing a constellation of spacecraft with the radio occultation links between the spacecraft, enabled by the infrastructure of the Global Positioning System. With the advent of small and less costly spacecraft, such as planetary CubeSats and other variations, such as the anticipated innovative Mars Cube One mission, crosslinks among small spacecraft can be used to study other planets in the near future. Advantages of this type of experiment include significantly greater geographical coverage, which could reach global coverage over a few weeks with a small number of spacecraft. Repeatability of the global coverage can lead to examining temperature-pressure profiles and ionospheric electron density profiles, on daily, seasonal, annual, or other time scales of interest. The higher signal-to-noise ratio for inter-satellite links, compared to a link to Earth, decreases the design demands on the instrumentation (smaller antennas and transmitters, etc.). After an actual Mars crosslink demonstration, this concept has been in development using Mars as a possible target. Scientific objectives, delivery methods, operational scenarios and end-to-end configuration have been documented. Science objectives include determining the state and variability of the lower Martian atmosphere, which has been an identified as a high priority objective by the Mars Exploration Program Analysis Group, particularly as it relates to entry, descent, and landing and ascent for future crewed and robotic missions. This paper will present the latest research on the

Magellan radio occultation measurements of atmospheric waves on Venus

Science.gov (United States)

Hinson, David P.; Jenkins, J. M.

1995-01-01

Radio occultation experiments were conducted at Venus on three consecutive orbits of the Magellan spacecraft in October 1991. Each occultation occurred over the same topography (67 deg N, 127 deg E) and at the same local time (22 hr 5 min), but the data are sensitive to zonal variations because the atmosphere rotates significantly during one orbit. Through comparisons between observations and predictions of standard wave theory, we have demonstrated that small-scale oscillations in retrieved temperature profiles as well as scintillations in received signal intensity are caused by a spectrum of vertically propagating internal gravity waves. There is a strong similarity between the intensity scintillations observed here and previous measurements, which pertain to a wide range of locations and experiment dates. This implies that the same basic phenomenon underlies all the observations and hence that gravity waves are a persistent, global feature of Venus' atmosphere. We obtained a fairly complete characterization of a gravity wave that appears above the middle cloud in temperature measurements on all three orbits. The amplitude and vertical wavelength are about 4 K and 2.5 km respectively, at 65 km. A model for radiative damping implies that the wave intrinsic frequency is approximately 2 x 10(exp 4) rad/sec, the corresponding ratio between horizontal and vertical wavelengths is approximately 100. The wave is nearly stationary relative to the surface or the Sun. Radiative attenuation limits the wave amplitude at altitudes above approximately 65 km, leading to wave drag on the mean zonal winds of about +0.4 m/sec per day (eastward). The sign, magnitude, and location of this forcing suggest a possible role in explaining the decrease with height in the zonal wind speed that is believed to occur above the cloud tops. Temperature oscillations with larger vertical wavelengths (5-10 km) were also observed on all three orbits, but we are able unable to interpret these

Pressure drop characteristics in tight-lattice bundles for reduced-moderation water reactors

International Nuclear Information System (INIS)

Tamai, Hidesada; Kureta, Masatoshi; Yoshida, Hiroyuki; Akimoto, Hajime

2004-01-01

The reduced-moderation water reactor (RMWR) consists of several distinctive structures; a triangular tight-lattice configuration and a double-flat core. In order to design the RMWR core from the point of view of thermal-hydraulics, an evaluation method on pressure drop characteristics in the rod bundles at the tight-lattice configuration is required. In this study, calculated results by the Martinelli-Nelson's and Hancox's correlations were compared with experimental results in 4 x 5 rod bundles and seven-rod bundles. Consequently, the friction loss in two-phase flows becomes smaller at the tight-lattice configuration with the hydraulic diameter less than about 3 mm. This reason is due to the difference of the configuration between the multi-rod bundle and the circular tube and due to the effect of the small hydraulic diameter on the two-phase multiplier. (author)

Determinants of participation in colorectal cancer screening with faecal occult blood testing

DEFF Research Database (Denmark)

von Euler-Chelpin, My; Brasso, Klaus; Lynge, Elsebeth

2009-01-01

BACKGROUND: Colorectal cancer is one of the most common cancers in men and women. Participation rates in faecal occult blood testing (FOBT) screening activities are, however, relatively low. In terms of lowering the colorectal cancer mortality, high participation rates are essential, and therefore......, but determinants varied across countries and test settings. There was no systematic variation in participation across age groups. CONCLUSION: The participation pattern depends in part on local circumstances, which makes it difficult to point to a general strategy for increasing the uptake in FOBT screening...

COSMIC Radio Occultation technique for measurement of the tropopause during tropical cyclones

DEFF Research Database (Denmark)

Biondi, Riccardo; Neubert, Torsten; Syndergaard, Stig

Basin during July 2008 and reached a maximum intensity of Category 3 and the typhoon Hondo, formed in the south Indian basin during February 2008 with maximum intensity of Category 4. Using measurements from a variety of earth observation satellites (A-Train constellation) and from aircraft together...... and they cool the tropopause layers. The GPS radio occultation technique is useful for studying severe weather phenomena because the GPS signals penetrate through clouds and allow measurements of atmospheric profiles related to temperature, pressure, and water vapour with high vertical resolution...

VizieR Online Data Catalog: Times of transits and occultations of WASP-12b (Patra+, 2017)

Science.gov (United States)

Patra, K. C.; Winn, J. N.; Holman, M. J.; Yu, L.; Deming, D.; Dai, F.

2017-08-01

Between 2016 October and 2017 February, we observed seven transits of WASP-12 with the 1.2m telescope at the Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona. Images were obtained with the KeplerCam detector through a Sloan r'-band filter. The typical exposure time was 15s, chosen to give a signal-to-noise ratio of about 200 for WASP-12. The field of view of this camera is 23.1' on a side. We used 2*2 binning, giving a pixel scale of 0.68''. We measured two new occultation times based on hitherto unpublished Spitzer observations in 2013 December (program 90186, P.I. Todorov). Two different transits were observed, one at 3.6μm and one at 4.5μm. The data take the form of a time series of 32*32-pixel subarray images, with an exposure time of 2.0s per image. The data were acquired over a wide range of orbital phases, but for our purpose, we analyzed only the ~14000 images within 4hr of each occultation. (1 data file).

DM ORI: A YOUNG STAR OCCULTED BY A DISTURBANCE IN ITS PROTOPLANETARY DISK

Energy Technology Data Exchange (ETDEWEB)

Rodriguez, Joseph E.; Stassun, Keivan G.; Lund, Michael B.; Weintraub, David A. [Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235 (United States); Cargile, Phillip [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Shappee, Benjamin J. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Siverd, Robert J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Pepper, Joshua [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015 (United States); Kochanek, Christopher S.; Gaudi, B. Scott; Stanek, Krzysztof Z.; Holoien, Thomas W.-S. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); James, David [Cerro Tololo InterAmerican Observatory, Casilla 603, La Serena (Chile); Kuhn, Rudolf B. [South African Astronomical Observatory, P.O. Box 9, Observatory 7935 (South Africa); Beatty, Thomas G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Prieto, Jose L. [Nucleo de Astronoma de la Facultad de Ingeniera, Universidad Diego Portales, Av. Ejercito 441, Santiago (Chile); Feldman, Daniel M.; Espaillat, Catherine C. [Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)

2016-11-01

In some planet formation theories, protoplanets grow gravitationally within a young star’s protoplanetary disk, a signature of which may be a localized disturbance in the disk’s radial and/or vertical structure. Using time-series photometric observations by the Kilodegree Extremely Little Telescope South project and the All-Sky Automated Survey for SuperNovae, combined with archival observations, we present the discovery of two extended dimming events of the young star, DM Ori. This young system faded by ∼1.5 mag from 2000 March to 2002 August and then again in 2013 January until 2014 September (depth ∼1.7 mag). We constrain the duration of the 2000–2002 dimming to be < 860 days, and the event in 2013–2014 to be < 585 days, separated by ∼12.5 years. A model of the spectral energy distribution indicates a large infrared excess consistent with an extensive circumstellar disk. Using basic kinematic arguments, we propose that DM Ori is likely being periodically occulted by a feature (possibly a warp or perturbation) in its circumstellar disk. In this scenario, the occulting feature is located >6 au from the host star, moving at ∼14.6 km s{sup −1} and is ∼4.9 au in width. This localized structure may indicate a disturbance such as that which may be caused by a protoplanet early in its formation.

Quantum tight-binding chains with dissipative coupling

International Nuclear Information System (INIS)

Mogilevtsev, D; Slepyan, G Ya; Garusov, E; Kilin, S Ya; Korolkova, N

2015-01-01

We present a one-dimensional tight-binding chain of two-level systems coupled only through common dissipative Markovian reservoirs. This quantum chain can demonstrate anomalous thermodynamic behavior contradicting Fourier law. Population dynamics of individual systems of the chain is polynomial with the order determined by the initial state of the chain. The chain can simulate classically hard problems, such as multi-dimensional random walks. (paper)

Detection of colorectal cancer in symptomatic outpatients without visible rectal bleeding: Validity of the fecal occult blood test

DEFF Research Database (Denmark)

Bjerregaard, Niels Christian; Tøttrup, Anders; Sørensen, Henrik Toft

2009-01-01

In 2002, a new diagnostic strategy in symptomatic outpatients without known established colorectal cancer risk factors aged 40 years or older was implemented in Denmark. Fecal occult blood test (Hemoccult Sensa®) was a part of that strategy in patients without visible rectal bleeding....

Efficient self-consistency for magnetic tight binding

Science.gov (United States)

Soin, Preetma; Horsfield, A. P.; Nguyen-Manh, D.

2011-06-01

Tight binding can be extended to magnetic systems by including an exchange interaction on an atomic site that favours net spin polarisation. We have used a published model, extended to include long-ranged Coulomb interactions, to study defects in iron. We have found that achieving self-consistency using conventional techniques was either unstable or very slow. By formulating the problem of achieving charge and spin self-consistency as a search for stationary points of a Harris-Foulkes functional, extended to include spin, we have derived a much more efficient scheme based on a Newton-Raphson procedure. We demonstrate the capabilities of our method by looking at vacancies and self-interstitials in iron. Self-consistency can indeed be achieved in a more efficient and stable manner, but care needs to be taken to manage this. The algorithm is implemented in the code PLATO. Program summaryProgram title:PLATO Catalogue identifier: AEFC_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFC_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 228 747 No. of bytes in distributed program, including test data, etc.: 1 880 369 Distribution format: tar.gz Programming language: C and PERL Computer: Apple Macintosh, PC, Unix machines Operating system: Unix, Linux, Mac OS X, Windows XP Has the code been vectorised or parallelised?: Yes. Up to 256 processors tested RAM: Up to 2 Gbytes per processor Classification: 7.3 External routines: LAPACK, BLAS and optionally ScaLAPACK, BLACS, PBLAS, FFTW Catalogue identifier of previous version: AEFC_v1_0 Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 2616 Does the new version supersede the previous version?: Yes Nature of problem: Achieving charge and spin self-consistency in magnetic tight binding can be very

Appraisal of the tight sands potential of the Sand Wash and Great Divide Basins

International Nuclear Information System (INIS)

1993-08-01

The volume of future tight gas reserve additions is difficult to estimate because of uncertainties in the characterization and extent of the resource and the performance and cost-effectiveness of stimulation and production technologies. Ongoing R ampersand D by industry and government aims to reduce the risks and costs of producing these tight resources, increase the certainty of knowledge of their geologic characteristics and extent, and increase the efficiency of production technologies. Some basins expected to contain large volumes of tight gas are being evaluated as to their potential contribution to domestic gas supplies. This report describes the results of one such appraisal. This analysis addresses the tight portions of the Eastern Greater Green River Basin (Sand Wash and Great Divide Subbasins in Northwestern Colorado and Southwestern Wyoming, respectively), with respect to estimated gas-in-place, technical recovery, and potential reserves. Geological data were compiled from public and proprietary sources. The study estimated gas-in-place in significant (greater than 10 feet net sand thickness) tight sand intervals for six distinct vertical and 21 areal units of analysis. These units of analysis represent tight gas potential outside current areas of development. For each unit of analysis, a ''typical'' well was modeled to represent the costs, recovery and economics of near-term drilling prospects in that unit. Technically recoverable gas was calculated using reservoir properties and assumptions about current formation evaluation and extraction technology performance. Basin-specific capital and operating costs were incorporated along with taxes, royalties and current regulations to estimate the minimum required wellhead gas price required to make the typical well in each of unit of analysis economic

Trapping a Knot into Tight Conformations by Intra-Chain Repulsions

Directory of Open Access Journals (Sweden)

Liang Dai

2017-02-01

Full Text Available Knots can occur in biopolymers such as DNA and peptides. In our previous study, we systematically investigated the effects of intra-chain interactions on knots and found that long-range repulsions can surprisingly tighten knots. Here, we use this knowledge to trap a knot into tight conformations in Langevin dynamics simulations. By trapping, we mean that the free energy landscape with respect to the knot size exhibits a potential well around a small knot size in the presence of long-range repulsions, and this potential can well lead to long-lived tight knots when its depth is comparable to or larger than thermal energy. We tune the strength of intra-chain repulsion such that a knot is weakly trapped. Driven by thermal fluctuations, the knot can escape from the trap and is then re-trapped. We find that the knot switches between tight and loose conformations—referred to as “knot breathing”. We use a Yukawa potential to model screened electrostatic interactions to explore the relevance of knot trapping and breathing in charged biopolymers. We determine the minimal screened length and the minimal strength of repulsion for knot trapping. We find that Coulomb-induced knot trapping is possible to occur in single-stranded DNA and peptides for normal ionic strengths.

Preconditioning Filter Bank Decomposition Using Structured Normalized Tight Frames

Directory of Open Access Journals (Sweden)

Martin Ehler

2015-01-01

Full Text Available We turn a given filter bank into a filtering scheme that provides perfect reconstruction, synthesis is the adjoint of the analysis part (so-called unitary filter banks, all filters have equal norm, and the essential features of the original filter bank are preserved. Unitary filter banks providing perfect reconstruction are induced by tight generalized frames, which enable signal decomposition using a set of linear operators. If, in addition, frame elements have equal norm, then the signal energy is spread through the various filter bank channels in some uniform fashion, which is often more suitable for further signal processing. We start with a given generalized frame whose elements allow for fast matrix vector multiplication, as, for instance, convolution operators, and compute a normalized tight frame, for which signal analysis and synthesis still preserve those fast algorithmic schemes.

Ernst Haeckel's biodynamics 1866 and the occult basis of organic farming

Science.gov (United States)

Kutschera, Ulrich

2016-01-01

ABSTRACT One hundred and 50 years ago (Sept. 1866), Ernst Haeckel published a monograph entitled General Morphology of Organisms, wherein key terms, such as Protista, Monera, ontogeny, phylogeny, ecology and the ‘biogenetic law’ where introduced. In addition, Haeckel coined the word “biodynamics” as a synonym for “general physiology.” In contrast, Rudolf Steiner's “biodynamic agriculture,” which originated in 1924, and was promoted via Ehrenfried Pfeiffer's book of 1938 with the same title, is an occult pseudoscience still popular today. The misuse of Haeckel's term to legitimize disproven homeopathic principles and esoteric rules within the context of applied plant research is unacceptable. PMID:27322020

Pluto's Atmosphere from the 2015 June 29 Ground-Based Stellar Occultation at the Time of the New Horizons Flyby

Czech Academy of Sciences Publication Activity Database

Sicardy, B.; Talbot, J.; Meza, E.; Camargo, J.I.B.; Desmars, J.; Gault, D.; Herald, D.; Kerr, S.; Pavlov, H.; Braga-Ribas, F.; Jelínek, Martin

2016-01-01

Roč. 819, č. 2 (2016), L38/1-L38/8 ISSN 2041-8205 Institutional support: RVO:67985815 Keywords : Kuiper belt objects * occultations * planets and satellites Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.522, year: 2016

Extent and kinetics of recovery of occult spinal cord injury

International Nuclear Information System (INIS)

Ang, K. Kian; Jiang, G.-L.; Feng Yan; Stephens, L. Clifton; Tucker, Susan L.; Price, Roger E.

2001-01-01

Purpose: To obtain clinically useful quantitative data on the extent and kinetics of recovery of occult radiation injury in primate spinal cord, after a commonly administered elective radiation dose of 44 Gy, given in about 2 Gy per fraction. Methods and Materials: A group of 56 rhesus monkeys was assigned to receive two radiation courses to the cervical and upper thoracic spinal cord, given in 2.2 Gy per fraction. The dose of the initial course was 44 Gy in all monkeys. Reirradiation dose was 57.2 Gy, given after 1-year (n 16) or 2-year (n = 20) intervals, or 66 Gy, given after 2-year (n = 4) or 3-year (n = 14) intervals. Two animals developed intramedullary tumors before reirradiation and, therefore, did not receive a second course. The study endpoint was myeloparesis, manifesting predominantly as lower extremity weakness and decrease in balance, occurring within 2.5 years after reirradiation, complemented by histologic examination of the spinal cord. The data obtained were analyzed along with data from a previous study addressing single-course tolerance, and data from a preliminary study of reirradiation tolerance. Results: Only 4 of 45 monkeys completing the required observation period (2-2.5 years after reirradiation, 3-5.5 years total) developed myeloparesis. The data revealed a substantial recovery of occult injury induced by 44 Gy within the first year, and suggested additional recovery between 1 and 3 years. Fitting the data with a model, assuming that all (single course and reirradiation) dose-response curves were parallel, yielded recovery estimates of 33.6 Gy (76%), 37.6 Gy (85%), and 44.6 Gy (101%) of the initial dose, after 1, 2, and 3 years, respectively, at the 5% incidence (D 5 ) level. The most conservative estimate, using a model in which it was assumed that there was no recovery between 1 and 3 years following initial irradiation and that the combined reirradiation curve was not necessarily parallel to the single-course curve, still showed an

An efficient magnetic tight-binding method for transition metals and alloys

DEFF Research Database (Denmark)

Barreteau, Cyrille; Spanjaard, Daniel; Desjonquères, Marie-Catherine

2016-01-01

that does not necessitate any further fitting is proposed to deal with systems made of several chemical elements. This model is extended to spin (and orbital) polarized materials by adding Stoner-like and spin–orbit interactions. Collinear and non-collinear magnetism as well as spin-spirals are considered......An efficient parameterized self-consistent tight-binding model for transition metals using s, p and d valence atomic orbitals as a basis set is presented. The parameters of our tight-binding model for pure elements are determined from a fit to bulk ab-initio calculations. A very simple procedure...

Tight junction-associated MARVEL proteins marveld3, tricellulin, and occludin have distinct but overlapping functions.

Science.gov (United States)

Raleigh, David R; Marchiando, Amanda M; Zhang, Yong; Shen, Le; Sasaki, Hiroyuki; Wang, Yingmin; Long, Manyuan; Turner, Jerrold R

2010-04-01

In vitro studies have demonstrated that occludin and tricellulin are important for tight junction barrier function, but in vivo data suggest that loss of these proteins can be overcome. The presence of a heretofore unknown, yet related, protein could explain these observations. Here, we report marvelD3, a novel tight junction protein that, like occludin and tricellulin, contains a conserved four-transmembrane MARVEL (MAL and related proteins for vesicle trafficking and membrane link) domain. Phylogenetic tree reconstruction; analysis of RNA and protein tissue distribution; immunofluorescent and electron microscopic examination of subcellular localization; characterization of intracellular trafficking, protein interactions, dynamic behavior, and siRNA knockdown effects; and description of remodeling after in vivo immune activation show that marvelD3, occludin, and tricellulin have distinct but overlapping functions at the tight junction. Although marvelD3 is able to partially compensate for occludin or tricellulin loss, it cannot fully restore function. We conclude that marvelD3, occludin, and tricellulin define the tight junction-associated MARVEL protein family. The data further suggest that these proteins are best considered as a group with both redundant and unique contributions to epithelial function and tight junction regulation.

Wounds caused by tight contact with the barrel-cylinder gap of revolvers.

Science.gov (United States)

Rogers, D R

1984-06-01

A case is presented in which the recognition of a tight cylinder gap contact wound was crucial. Experiments were carried out to reproduce the wound which was noted on the hand of a robbery suspect. Tight contact with the cylinder gap of a revolver produces a characteristic, readily recognizable wound. It is characterized by an L-shaped pattern of powder residue. Along one axis a searing burn may occur which may be deep and which may lead to significant tissue destruction.

Management of Small Urethrocutaneous Fistula by Tight Ligation ...

African Journals Online (AJOL)

After identifying the fistulous opening, the fistula tract was circumferentially and meticulously dissected ,then the dissected tract was lifted up and the base was ligated tightly with 5/0 vicryl, the external epithelium of the dissected tract was fulgurated with the diathermy, then a second layer of local soft tissue was secured over ...

Tight Reference Frame–Independent Quantum Teleportation

Directory of Open Access Journals (Sweden)

Dominic Verdon

2017-01-01

Full Text Available We give a tight scheme for teleporting a quantum state between two parties whose reference frames are misaligned by an action of a finite symmetry group. Unlike previously proposed schemes, ours requires no additional tokens or data to be passed between the participants; the same amount of classical information is transferred as for ordinary quantum teleportation, and the Hilbert space of the entangled resource is of the same size. In the terminology of Peres and Scudo, our protocol relies on classical communication of unspeakable information.

Greenhouse gas profiling by infrared-laser and microwave occultation: retrieval algorithm and demonstration results from end-to-end simulations

Directory of Open Access Journals (Sweden)

V. Proschek

2011-10-01

Full Text Available Measuring greenhouse gas (GHG profiles with global coverage and high accuracy and vertical resolution in the upper troposphere and lower stratosphere (UTLS is key for improved monitoring of GHG concentrations in the free atmosphere. In this respect a new satellite mission concept adding an infrared-laser part to the already well studied microwave occultation technique exploits the joint propagation of infrared-laser and microwave signals between Low Earth Orbit (LEO satellites. This synergetic combination, referred to as LEO-LEO microwave and infrared-laser occultation (LMIO method, enables to retrieve thermodynamic profiles (pressure, temperature, humidity and accurate altitude levels from the microwave signals and GHG profiles from the simultaneously measured infrared-laser signals. However, due to the novelty of the LMIO method, a retrieval algorithm for GHG profiling is not yet available. Here we introduce such an algorithm for retrieving GHGs from LEO-LEO infrared-laser occultation (LIO data, applied as a second step after retrieving thermodynamic profiles from LEO-LEO microwave occultation (LMO data. We thoroughly describe the LIO retrieval algorithm and unveil the synergy with the LMO-retrieved pressure, temperature, and altitude information. We furthermore demonstrate the effective independence of the GHG retrieval results from background (a priori information in discussing demonstration results from LMIO end-to-end simulations for a representative set of GHG profiles, including carbon dioxide (CO₂, water vapor (H₂O, methane (CH₄, and ozone (O₃. The GHGs except for ozone are well retrieved throughout the UTLS, while ozone is well retrieved from about 10 km to 15 km upwards, since the ozone layer resides in the lower stratosphere. The GHG retrieval errors are generally smaller than 1% to 3% r.m.s., at a vertical resolution of about 1 km. The retrieved profiles also appear unbiased, which points

Management of occult stress urinary incontinence with prolapse surgery.

Science.gov (United States)

Al-Mandeel, H; Al-Badr, A

2013-08-01

Pelvic organ prolapse (POP) and stress urinary incontinence (SUI), are two common health-related conditions, each affecting up to 50% women worldwide. Stress urinary incontinence only observed after the reduction of co-existent prolapse is called occult SUI (OSUI), and is found in up to 80% of women with advanced POP. Although there is no consensus on how to diagnose OSUI, there are several reported methods to better diagnose. Counseling symptomatically continent women with POP concerning the potential risk for developing SUI postoperatively cannot be overstated. Evidence suggests that positive OSUI in symptomatically continent women who are planning to have POP repair is associated with a high risk of POSUI, furthermore, adding continence procedure is found to reduce postoperative SUI. Therefore, adding continence surgery at the time of POP surgery in patients who are found to have OSUI preoperatively is advocated.

Symptoms of thyrotoxicosis, bone metabolism and occult atrial fibrillation in older women with mild endogenous subclinical hyperthyroidism.

Science.gov (United States)

Rosario, Pedro Weslley; Carvalho, Marina; Calsolari, Maria Regina

2016-07-01

The objective of this study was to evaluate symptoms of thyrotoxicosis, bone turnover, bone mineral density (BMD) and occult atrial fibrillation (AF) in women ≥65 years with mild endogenous subclinical hyperthyroidism (SCH). Cross-sectional and case-control study. Signs and symptoms of thyrotoxicosis, serum carboxyterminal telopeptide (CTx) and procollagen type I N-terminal propeptide (PINP), BMD, resting electrocardiogram (ECG) and 72-h ECG monitoring were evaluated in 180 women ≥65 years, including 90 with mild SCH (TSH between 0·1 and 0·4 mIU/l) and 90 euthyroid controls matched for age and body mass index. Symptom Rating Scale scores did not differ between patients and controls. None of the patients with SCH scored 20 points, a score compatible with clinical thyrotoxicosis. Eighty patients with SCH (89%) obtained seven or fewer points, a score compatible with euthyroidism. No difference in serum CTx or PINP concentrations was observed between patients and controls. There was also no correlation between these markers and TSH, free T4 or total T3 levels. Finally, no difference in femoral neck or lumbar spine BMD was observed between patients with SCH and controls. Three patients with SCH (3·3%) and two euthyroid women (2·2%) had known AF or AF in the resting ECG. ECG monitoring for 72 h revealed episodes of occult AF in 1/87 patients with SCH and in 1/88 euthyroid women (1·1%). Mild endogenous SCH (TSH between 0·1 and 0·4 mIU/l) was not associated with symptoms of thyrotoxicosis, altered bone metabolism or a higher prevalence of occult AF in women ≥65 years. © 2015 John Wiley & Sons Ltd.

Two-Finger Tightness: What Is It? Measuring Torque and Reproducibility in a Simulated Model.

Science.gov (United States)

Acker, William B; Tai, Bruce L; Belmont, Barry; Shih, Albert J; Irwin, Todd A; Holmes, James R

2016-05-01

Residents in training are often directed to insert screws using "two-finger tightness" to impart adequate torque but minimize the chance of a screw stripping in bone. This study seeks to quantify and describe two-finger tightness and to assess the variability of its application by residents in training. Cortical bone was simulated using a polyurethane foam block (30-pcf density) that was prepared with predrilled holes for tightening 3.5 × 14-mm long cortical screws and mounted to a custom-built apparatus on a load cell to capture torque data. Thirty-three residents in training, ranging from the first through fifth years of residency, along with 8 staff members, were directed to tighten 6 screws to two-finger tightness in the test block, and peak torque values were recorded. The participants were blinded to their torque values. Stripping torque (2.73 ± 0.56 N·m) was determined from 36 trials and served as a threshold for failed screw placement. The average torques varied substantially with regard to absolute torque values, thus poorly defining two-finger tightness. Junior residents less consistently reproduced torque compared with other groups (0.29 and 0.32, respectively). These data quantify absolute values of two-finger tightness but demonstrate considerable variability in absolute torque values, percentage of stripping torque, and ability to consistently reproduce given torque levels. Increased years in training are weakly correlated with reproducibility, but experience does not seem to affect absolute torque levels. These results question the usefulness of two-finger tightness as a teaching tool and highlight the need for improvement in resident motor skill training and development within a teaching curriculum. Torque measuring devices may be a useful simulation tools for this purpose.

Are you afraid of the dark? Notes on the psychology of belief in histories of science and the occult.

Science.gov (United States)

Sommer, Andreas

2016-04-02

The popular view of the inherent conflict between science and the occult has been rendered obsolete by recent advances in the history of science. Yet, these historiographical revisions have gone unnoticed in the public understanding of science and public education at large. Particularly, reconstructions of the formation of modern psychology and its links to psychical research can show that the standard view of the latter as motivated by metaphysical bias fails to stand up to scrutiny. After highlighting certain basic methodological maxims shared by psychotherapists and historians, I will try to counterbalance simplistic claims of a 'need to believe' as a precondition of scientific open-mindedness regarding the occurrence of parapsychological phenomena by discussing instances revealing a presumably widespread 'will to disbelieve' in the occult. I shall argue that generalized psychological explanations are only helpful in our understanding of history if we apply them in a symmetrical manner.

THE ATMOSPHERES OF THE HOT-JUPITERS KEPLER-5b AND KEPLER-6b OBSERVED DURING OCCULTATIONS WITH WARM-SPITZER AND KEPLER

Energy Technology Data Exchange (ETDEWEB)

Desert, Jean-Michel; Charbonneau, David; Fressin, Francois; Latham, David W. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Madhusudhan, Nikku [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Knutson, Heather A. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Deming, Drake [Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Borucki, William J. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Brown, Timothy M. [Las Cumbres Observatory Global Telescope, Goleta, CA 93117 (United States); Caldwell, Douglas [SETI Institute, Mountain View, CA 94043 (United States); Ford, Eric B. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Gilliland, Ronald L. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Marcy, Geoffrey W. [Berkeley Astronomy Department, University of California, Berkeley, CA 94720 (United States); Seager, Sara, E-mail: jdesert@cfa.harvard.edu [Massachusetts Institute of Technology, Cambridge, MA 02159 (United States)

2011-11-01

This paper reports the detection and the measurements of occultations of the two transiting hot giant exoplanets Kepler-5b and Kepler-6b by their parent stars. The observations are obtained in the near-infrared with Warm-Spitzer Space Telescope and at optical wavelengths by combining more than a year of Kepler photometry. The investigation consists of constraining the eccentricities of these systems and of obtaining broadband emergent photometric data for individual planets. For both targets, the occultations are detected at the 3{sigma} level at each wavelength with mid-occultation times consistent with circular orbits. The brightness temperatures of these planets are deduced from the infrared observations and reach T{sub Spitzer} = 1930 {+-} 100 K and T{sub Spitzer} = 1660 {+-} 120 K for Kepler-5b and Kepler-6b, respectively. We measure optical geometric albedos A{sub g} in the Kepler bandpass and find A{sub g} = 0.12 {+-} 0.04 for Kepler-5b and A{sub g} = 0.11 {+-} 0.04 for Kepler-6b, leading to upper an limit for the Bond albedo of A{sub B} {<=} 0.17 in both cases. The observations for both planets are best described by models for which most of the incident energy is redistributed on the dayside, with only less than 10% of the absorbed stellar flux redistributed to the nightside of these planets.

Experience in North America Tight Oil Reserves Development. Horizontal Wells and Multistage Hydraulic Fracturing

Directory of Open Access Journals (Sweden)

R.R. Ibatullin

2017-09-01

Full Text Available The accelerated development of horizontal drilling technology in combination with the multistage hydraulic fracturing of the reservoir has expanded the geological conditions for commercial oil production from tight reservoirs in North America. Geological and physical characteristics of tight reservoirs in North America are presented, as well as a comparison of the geological and physical properties of the reservoirs of the Western Canadian Sedimentary Basin and the Volga-Ural oil and gas province, in particular, in the territory of Tatarstan. The similarity of these basins is shown in terms of formation and deposition. New drilling technologies for horizontal wells (HW and multistage hydraulic fracturing are considered. The drilling in tight reservoirs is carried out exclusively on hydrocarbon-based muds The multi-stage fracturing technology with the use of sliding sleeves, and also slick water – a low-viscous carrier for proppant is the most effective solution for conditions similar to tight reservoirs in the Devonian formation of Tatarstan. Tax incentives which are actively used for the development of HW and multistage fracturing technologies in Canada are described. wells, multistage fracturing

Sensitivity of airborne radio occultation to tropospheric properties over ocean and land

Directory of Open Access Journals (Sweden)

F. Xie

2018-02-01

Full Text Available Airborne radio occultation (ARO measurements collected during a ferry flight at the end of the PRE-Depression Investigation of Cloud-systems in the Tropics (PREDICT field campaign from the Virgin Islands to Colorado are analyzed. The large contrast in atmospheric conditions along the flight path from the warm and moist Caribbean Sea to the much drier and cooler continental conditions provides a unique opportunity to address the sensitivity of ARO measurements to the tropospheric temperature and moisture changes. This long flight at nearly constant altitude (∼ 13 km provided an optimal configuration for simultaneous high-quality ARO measurements from two high-gain side-looking antennas, as well as one relatively lower gain zenith (top antenna. The omnidirectional top antenna has the advantage of tracking robustly more occulting satellites in all direction as compared to the limited-azimuth tracking of the side-looking antennas. Two well-adapted radio-holographic bending angle retrieval methods, full-spectrum inversion (FSI and phase matching (PM, were compared with the standard geometric-optics (GO retrieval method. Comparison of the ARO retrievals from the top antenna with the near-coincident ECMWF reanalysis-interim (ERA-I profiles shows only a small root-mean-square (RMS refractivity difference of ∼ 0.3 % in the drier upper troposphere from ∼ 5 to ∼ 11.5 km over both land and ocean. Both the FSI and PM methods improve the ARO retrievals in the moist lower troposphere and reduce the negative bias found in the GO retrieval due to atmospheric multipath. In the lowest layer of the troposphere, the ARO refractivity derived using FSI shows a negative bias of about −2 %. The increase of the refractivity bias occurs below 5 km over the ocean and below 3.5 km over land, corresponding to the approximate altitude of large vertical moisture gradients above the ocean and land surface, respectively. In comparisons to

A modification to the standard ionospheric correction method used in GPS radio occultation

Directory of Open Access Journals (Sweden)

S. B. Healy

2015-08-01

Full Text Available A modification to the standard bending-angle correction used in GPS radio occultation (GPS-RO is proposed. The modified approach should reduce systematic residual ionospheric errors in GPS radio occultation climatologies. A new second-order term is introduced in order to account for a known source of systematic error, which is generally neglected. The new term has the form κ(a × (αL1(a-αL2(a2, where a is the impact parameter and (αL1, αL2 are the L1 and L2 bending angles, respectively. The variable κ is a weak function of the impact parameter, a, but it does depend on a priori ionospheric information. The theoretical basis of the new term is examined. The sensitivity of κ to the assumed ionospheric parameters is investigated in one-dimensional simulations, and it is shown that κ ≃ 10–20 rad−1. We note that the current implicit assumption is κ=0, and this is probably adequate for numerical weather prediction applications. However, the uncertainty in κ should be included in the uncertainty estimates for the geophysical climatologies produced from GPS-RO measurements. The limitations of the new ionospheric correction when applied to CHAMP (Challenging Minisatellite Payload measurements are noted. These arise because of the assumption that the refractive index is unity at the satellite, made when deriving bending angles from the Doppler shift values.

Assessment of occult cervical lymph node metastasis in primary squamous cell carcinoma of the head and neck by computed tomography

International Nuclear Information System (INIS)

Shakil, U.

2015-01-01

To determine the frequency of occult (node negative) cervical lymph node metastasis in primary head and neck squamous cell carcinoma, using contrast enhanced computed tomography (CT). Study Design: Cross sectional descriptive study. Place and Duration of Study: Study was conducted in Department of Radiology, Combined Military Hospital Rawalpindi. Duration of the study was 06 months i.e. from 19th February 2011 to 19th August 2011. Patients and Methods: A total of 141 cases, fulfilling the inclusion criteria, reporting to the radiology department, were included in the study after seeking written informed consent. All patients underwent contrast enhanced CT scan of the neck from base of skull to root of neck using Asteion Whole Body X-ray CT Scanner (Model TSX-021A). Images were evaluated for the presence or absence of cervical lymph node metastasis according to the cervical lymph node metastatic criteria at each level of the neck. Results: Of the 141 patients with clinically no head and neck squamous cell carcinoma, 45.4% were found to have lymph node metastases. Frequency of occult metastases in squamous cell carcinoma of oral cavity was 47.6%, oropharynx 23.5%, larynx 33.3% and hypopharynx 78.6%. Conclusion: In clinically node negative neck, the risk of lymph node metastases is significantly high in patients of head and neck squamous cell carcinoma in our population. All patients presenting with node negative neck should undergo CT scans for early detection of occult metastasis. (author)

INFLUENCE OF FABRIC TIGHTNESS ON SPIRALITY OF WEFTKNITTED PLAIN COTTON FABRIC

Directory of Open Access Journals (Sweden)

A.K.M. Mobarok Hossain

2011-01-01

Full Text Available Global demand for knitted garments is growing at a faster rate than that of woven items.Currently around 50% of clothing needs in the developed countries is met by knit goods. So ensuring the required quality in a knitted fabric is a vital issue for the manufacturer. One of the major problems encountered in knitted fabric is spirality. It affects particularly single jersey fabric and presents a serious problem during garment confection and use. So controlling spirality is a basic requirement for producing quality knitted fabric. Though there are several factors that contribute to knitted fabric spirality, yarn twist and relative tightness of the fabric are said tobe the most significant ones. In this work the basic single jersey fabric, i.e. plain jersey cotton fabrics were produced by a Hosiery knitting machine and spirality values were observed for different yarn T.P.I. and tightness factor at relaxed state. It was found that tightness factor has a direct influence on knitted fabric spirality with a high degree of correlation. The work thus gives an idea to deal this problem by controlling the knitting parameters.

Long-term comparison of the ionospheric F2 layer electron density peak derived from ionosonde data and Formosat-3/COSMIC occultations

Directory of Open Access Journals (Sweden)

Limberger Marco

2015-01-01

Full Text Available Electron density profiles (EDPs derived from GNSS radio occultation (RO measurements provide valuable information on the vertical electron density structure of the ionosphere and, among others, allow the extraction of key parameters such as the maximum electron density NmF2 and the corresponding peak height hmF2 of the F2 layer. An efficient electron density retrieval method, developed at the UPC (Barcelona, Spain, has been applied in this work to assess the accuracy of NmF2and hmF2 as determined from Formosat-3/COSMIC (F-3/C radio occultation measurements for a period of more than half a solar cycle between 2006 and 2014. Ionosonde measurements of the Space Physics Interactive Data Resource (SPIDR network serve as a reference. Investigations on the global trend as well as comparisons of the F2 layer electron density peaks derived from both occultations and ionosonde measurements are carried out. The studies are performed in the global domain and with the distinction of different latitude sectors around the magnetic equator ±[0°, 20°], ±]20°, 60°] and ±]60°, 90°] and local times (LT accounting for different ionospheric conditions at night (02:00 LT ± 2 h, dawn (08:00 LT ± 2 h, and day (14:00 LT ± 2 h. The mean differences of F2 layer electron density peaks observed by F-3/C and ionosondes are found to be insignificant. Relative variations of the peak differences are determined in the range of 22%–30% for NmF2 and 10%–15% for hmF2. The consistency of observations is generally high for the equatorial and mid-latitude sectors at daytime and dawn whereas degradations have been detected in the polar regions and during night. It is shown, that the global averages of NmF2 and hmF2 derived from F-3/C occultations appear as excellent indicators for the solar activity.

Portable Telescopic Observations of the 3 June 2017 Stellar Occultation by New Horizons Kuiper Extended Mission Target (486958) 2014 MU69

Science.gov (United States)

Verbiscer, Anne J.; Buie, Marc W.; Porter, Simon Bernard; Tamblyn, Peter; Terrell, Dirk; Benecchi, Susan; Parker, Alex; Soto, Alejandro; Wasserman, Lawrence H.; Young, Eliot F.; Zangari, Amanda Marie; New Horizons MU69 Occultation Team

2017-10-01

The New Horizons spacecraft will encounter the cold classical Kuiper Belt Object (486958) 2014 MU69 on 1 January 2019. Because it is extremely faint (V mag ~27), MU69 has only been directly observed by the Hubble Space Telescope since its discovery (by HST) in 2014 (Spencer et al. 2015 EPSC 10, 417S). Current knowledge of the physical properties of MU69 is therefore limited to its red color (F606W-F814W = 0.99 ± 0.18, Benecchi et al. 2017) and a crude estimate on its size (20-40 km) based on association with other cold classical KBO visible albedos (0.04-0.15). Stellar occultations are powerful tools with which to measure the size and shape of objects whose distance and faintness precludes any spatially resolved observations. Here we report the results of a stellar occultation of a g’=15.33 magnitude star by MU69 on 3 June 2017. The shadow path crossed both southern Africa and South America. We deployed 12 portable telescopes from Mendoza, Argentina and 13 portable telescopes from Clanwilliam, Western Cape, South Africa. Although 24 of these 25 telescopes successfully observed the occultation star at the predicted event time, no solid body detection appeared in any of the acquired lightcurves. Following the successful detection of MU69 by stellar occultation on 17 July 2017, revised predictions of the location of the shadow path on 3 June now allow the lightcurves obtained on 3 June to place important constraints on the environment surrounding MU69 as well as upper limits on the size of any small satellites in the regions probed. This work would not have been possible without the financial support of NASA, the New Horizons Project, the astrometric support of the Gaia mission, and logistical support from the South African Astronomical Observatory, the US Embassies in Buenos Aires and Pretoria and the US Consulate in Cape Town.

Excessive blinking and ataxia in a child with occult neuroblastoma and voltage-gated potassium channel antibodies.

LENUS (Irish Health Repository)

Allen, Nicholas M

2012-05-01

A previously healthy 9-year-old girl presented with a 10-day history of slowly progressive unsteadiness, slurred speech, and behavior change. On examination there was cerebellar ataxia and dysarthria, excessive blinking, subtle perioral myoclonus, and labile mood. The finding of oligoclonal bands in the cerebrospinal fluid prompted paraneoplastic serological evaluation and search for an occult neural crest tumor. Antineuronal nuclear autoantibody type 1 (anti-Hu) and voltage-gated potassium channel complex antibodies were detected in serum. Metaiodobenzylguanidine scan and computed tomography scan of the abdomen showed a localized abdominal mass in the region of the porta hepatis. A diagnosis of occult neuroblastoma was made. Resection of the stage 1 neuroblastoma and treatment with pulsed corticosteroids resulted in resolution of all symptoms and signs. Excessive blinking has rarely been described with neuroblastoma, and, when it is not an isolated finding, it may be a useful clue to this paraneoplastic syndrome. Although voltage-gated potassium channel complex autoimmunity has not been described previously in the setting of neuroblastoma, it is associated with a spectrum of paraneoplastic neurologic manifestations in adults, including peripheral nerve hyperexcitability disorders.

Taiwan/TriG Radio Occultation Process System (TROPS): A Brief Introduction of Atmospheric Productions

Science.gov (United States)

Huang, Cheng-Yung; Yeh, Wen-Hao; Tseng, Tzu-Pang; Chen, Linton J.

2017-04-01

Global Positioning System (GPS) Radio Occultation (RO) technique has been used to investigate the Earth's atmosphere since 1990s. In 2006, Taiwan has launched six low Earth orbit (LEO) satellites as a RO constellation mission, named FORMOSAT-3 /COSMIC (F-3/C). F-3/C mission can release 1500-2500 data sets per day for both neutral atmosphere and ionosphere. With the advent of Global Navigation Satellite System (GNSS) in ten years and FORMOSAT-7/COSMIC-2 (F-7/C-2) mission, 12 LEO satellites are planned to be launched and deployed in two clusters of 6-satellites into the designated low and high inclination orbits in 2017 and 2020(TBD), respectively. The amount of RO data set will increase to about 8000 set per day with the using of GNSS TriG (GPS, Glonass, Galileo) receivers. The first phase of FS-7 mission is designed to low inclination (24 deg) orbit to improve the ability of server weather forecasting, like typhoon and monsoon rainfall around tropical region. The second is high inclination (72 deg) for global distribution. In order to observe better water vapor profiles, the 4x3 antennas arrays will be on board to receive weak signals which pass through low troposphere around earth surface. This report will introduce the status of F-7/C-2 mission and atmospheric part of occultation data process software TROPS.

Dielectric constant of graphene-on-polarized substrate: A tight ...

Indian Academy of Sciences (India)

2017-06-24

Jun 24, 2017 ... We report here a microscopic tight-binding theoretical study of the dynamic dielectric response of graphene-on-polarizable substrate with impurity. The Hamiltonian consists of first, second and third nearest neighbour electron hopping interactions besides doping and substrate-induced effects on graphene.

Intraoperative tight glucose control using hyperinsulinemic normoglycemia increases delirium after cardiac surgery.

Science.gov (United States)

Saager, Leif; Duncan, Andra E; Yared, Jean-Pierre; Hesler, Brian D; You, Jing; Deogaonkar, Anupa; Sessler, Daniel I; Kurz, Andrea

2015-06-01

Postoperative delirium is common in patients recovering from cardiac surgery. Tight glucose control has been shown to reduce mortality and morbidity. Therefore, the authors sought to determine the effect of tight intraoperative glucose control using a hyperinsulinemic-normoglycemic clamp approach on postoperative delirium in patients undergoing cardiac surgery. The authors enrolled 198 adult patients having cardiac surgery in this randomized, double-blind, single-center trial. Patients were randomly assigned to either tight intraoperative glucose control with a hyperinsulinemic-normoglycemic clamp (target blood glucose, 80 to 110 mg/dl) or standard therapy (conventional insulin administration with blood glucose target, battery. The authors considered patients to have experienced postoperative delirium when Confusion Assessment Method testing was positive at any assessment. A positive Confusion Assessment Method was defined by the presence of features 1 (acute onset and fluctuating course) and 2 (inattention) and either 3 (disorganized thinking) or 4 (altered consciousness). Patients randomized to tight glucose control were more likely to be diagnosed as being delirious than those assigned to routine glucose control (26 of 93 vs. 15 of 105; relative risk, 1.89; 95% CI, 1.06 to 3.37; P = 0.03), after adjusting for preoperative usage of calcium channel blocker and American Society of Anesthesiologist physical status. Delirium severity, among patients with delirium, was comparable with each glucose management strategy. Intraoperative hyperinsulinemic-normoglycemia augments the risk of delirium after cardiac surgery, but not its severity.

Experimental Air-Tightness Analysis in Mediterranean Buildings after Windows Retrofit

Directory of Open Access Journals (Sweden)

Francesca Romana d’Ambrosio Alfano

2016-09-01

Full Text Available Energy saving and Indoor Air Quality (IAQ in buildings are strongly affected by air leakages. Several studies reveal that the energy loss owing to leaky windows can account for up to 40% of the total building energy demand. Furthermore, at the design stage, the possible infiltration of outdoor air through windows is not taken into account when determining the nominal outdoor airflow rate of the ventilation system. This practice may result in an oversizing of the ventilation system and consequent energy waste. Thus, the air-tightness class of a wall assembly should be assessed for each window component considering the type of material, the presence of the seal, the type of closure, the sealing and the maintenance condition. In this paper, the authors present the experimental results of air-tightness measurements carried out using the fan pressurization method in three residential buildings located in the Mediterranean region before and after a window retrofit. Two different window retrofits were investigated: the application of rubber seals on window frames and the substitution of existing windows with new certified high performance windows. The effectiveness of such retrofits was estimated also in terms of energy saving. Test results demonstrated a high variability of the building air tightness after window retrofits, despite the fact that air tight–certified windows were used.

Theory for the effects of turbulence in a planetary atmosphere on radio occultation

Science.gov (United States)

Woo, R.; Ishimaru, A.

1974-01-01

Rytov's method is used to formulate the correlation functions for log-amplitude and phase fluctuations for both spherical and plane wave propagation in a turbulent medium whose correlation function for refractive index fluctuations is described by the product of a function of the average coordinate and a function of the difference coordinate. The results are applied to the study of radio occultation effects due to the atmosphere of Venus in the case of a flyby space probe. It is assumed that turbulence of isotropic and smoothly varying characteristics occurs in the Venusian atmosphere.

GEROS-ISS: GNSS REflectometry, Radio Occultation and Scatterometry onboard the International Space Station

DEFF Research Database (Denmark)

Wickert, Jens; Cardellach, Estel; Bandeiras, Jorge

2016-01-01

GEROS-ISS stands for GNSS REflectometry, radio occultation, and scatterometry onboard the International Space Station (ISS). It is a scientific experiment, successfully proposed to the European Space Agency in 2011. The experiment as the name indicates will be conducted on the ISS. The main focus...... of GEROS-ISS is the dedicated use of signals from the currently available Global Navigation Satellite Systems (GNSS) in L-band for remote sensing of the Earth with a focus to study climate change. Prime mission objectives are the determination of the altimetric sea surface height of the oceans...

[Identification of occult disseminated tumor cells by recombinant herpes simplex virus expressing GFP (HSV(GFP))].

Science.gov (United States)

Han, Xiang-ping; Shi, Gui-lan; Wang, Cheng-feng; Li, Jie; Zhang, Jian-wei; Zhang, Yu; Zhang, Shu-ren; Liu, Bin-lei

2012-12-01

To develop a novel rapid protocol for the detection of occult disseminated tumor cells by a recombinant herpes simplex virus expressing GFP (HSV(GFP)). Tumor cells of seven cell lines were exposed to HSV(GFP) and then examined for GFP expression by fluorescence microscopy. Various numbers of tumor cells (10, 100, 1000, 10 000) were mixed into 2 ml human whole blood, separated with lymphocytes separation medium, exposed to HSV(GFP), incubated at 37°C for 6 - 24 h and then counted for the number of green cells under the fluorescence microscope. Some clinical samples including peripheral blood, pleural effusion, ascites, spinal fluid from tumor-bearing patients were screened using this protocol in parallel with routine cytological examination. HSV(GFP) was able to infect all 7 tumor cell lines indicating that the HSV(GFP) can be used to detect different types of tumor cells. The detection sensitivity was 10 cancer cells in 2 ml whole blood. In the clinical samples, there were 4/15 positive by routine cytological examination but 11/15 positive by HSV(GFP), indicating a higher sensitivity of this new protocol. Recombinant herpes simplex virus-mediated green fluorescence is a simple and sensitive technique for the identification of occult disseminated cancer cells including circulating tumor cells (CTCs).

Morphologically occult systemic mastocytosis in bone marrow: clinicopathologic features and an algorithmic approach to diagnosis.

Science.gov (United States)

Reichard, Kaaren K; Chen, Dong; Pardanani, Animesh; McClure, Rebecca F; Howard, Matthew T; Kurtin, Paul J; Wood, Adam J; Ketterling, Rhett P; King, Rebecca L; He, Rong; Morice, William G; Hanson, Curtis A

2015-09-01

Bone marrow (BM) biopsy specimens involved by systemic mastocytosis (SM) typically show multifocal, compact, dense aggregates of spindled mast cells (MCs). However, some cases lack aggregate formation and fulfill the World Health Organization 2008 criteria for SM, based on minor criteria. We identified 26 BM cases of KIT D816V-mutated, morphologically occult SM in the BM. All patients had some combination of allergic/MC activating symptoms. Peripheral blood counts were generally normal. BM aspirates showed 5% or less MCs, which were only occasionally spindled. BM biopsy specimens showed no morphologic classic MC lesions. Tryptase immunohistochemistry (IHC) demonstrated interstitial, individually distributed MCs (up to 5%) with prominent spindling, lacking aggregate formation. MCs coexpressed CD25 by IHC and/or flow cytometry. Spindled MCs constituted more than 25% of total MCs in all cases and more than 50% in 20 of 26 cases. Morphologically occult involvement of normal-appearing BM by SM will be missed without appropriate clinical suspicion and pathologic evaluation by tryptase and CD25 IHC and KIT D816V mutation analysis. On the basis of these findings, we propose a cost-effective, data-driven, evidence-based algorithmic approach to the workup of these cases. Copyright© by the American Society for Clinical Pathology.

The experimental modeling of gas percolation mechanisms in a coal-measure tight sandstone reservoir: A case study on the coal-measure tight sandstone gas in the Upper Triassic Xujiahe Formation, Sichuan Basin, China

Directory of Open Access Journals (Sweden)

Shizhen Tao

2016-12-01

Full Text Available Tight sandstone gas from coal-measure source rock is widespread in China, and it is represented by the Xujiahe Formation of the Sichuan Basin and the Upper Paleozoic of the Ordos Basin. It is affected by planar evaporative hydrocarbon expulsion of coal-measure source rock and the gentle structural background; hydrodynamics and buoyancy play a limited role in the gas migration-accumulation in tight sandstone. Under the conditions of low permeability and speed, non-Darcy flow is quite apparent, it gives rise to gas-water mixed gas zone. In the gas displacing water experiment, the shape of percolation flow curve is mainly influenced by core permeability. The lower the permeability, the higher the starting pressure gradient as well as the more evident the non-Darcy phenomenon will be. In the gas displacing water experiment of tight sandstone, the maximum gas saturation of the core is generally less than 50% (ranging from 30% to 40% and averaging at 38%; it is similar to the actual gas saturation of the gas zone in the subsurface core. The gas saturation and permeability of the core have a logarithm correlation with a correlation coefficient of 0.8915. In the single-phase flow of tight sandstone gas, low-velocity non-Darcy percolation is apparent; the initial flow velocity (Vd exists due to the slippage effect of gas flow. The shape of percolation flow curve of a single-phase gas is primarily controlled by core permeability and confining pressure; the lower the permeability or the higher the confining pressure, the higher the starting pressure (0.02–0.08 MPa/cm, whereas, the higher the quasi-initial flow speed, the longer the nonlinear section and the more obvious the non-Darcy flow will be. The tight sandstone gas seepage mechanism study shows that the lower the reservoir permeability, the higher the starting pressure and the slower the flow velocity will be, this results in the low efficiency of natural gas migration and accumulation as well as

Anemia and thrombocytopenia as initial symptoms of occult breast cancer with bone marrow metastasis

OpenAIRE

Liu, Lulu; Zhang, Jingjing; Chen, Mingtai; Ren, Saisai; Liu, Haihui; Zhang, Hao

2017-01-01

Abstract Rationale: Occult breast cancer (OBC) is a rare type of breast cancer without any symptoms in the breast and is often presented with initial symptoms of axillary lymph node metastasis or other metastases. The low incidence rates of OBC make it a great challenge to diagnose and cure. Patient concerns: Our case was a 58-year-old female affected by dizziness and fatigue for nearly a month. Blood tests revealed anemia and thrombocytopenia, and pathological results of a bone marrow biopsy...

Feasibility study on application of volume acid fracturing technology to tight gas carbonate reservoir development

Directory of Open Access Journals (Sweden)

Nianyin Li

2015-09-01

Full Text Available How to effectively develop tight-gas carbonate reservoir and achieve high recovery is always a problem for the oil and gas industry. To solve this problem, domestic petroleum engineers use the combination of the successful experiences of North American shale gas pools development by stimulated reservoir volume (SRV fracturing with the research achievements of Chinese tight gas development by acid fracturing to propose volume acid fracturing technology for fractured tight-gas carbonate reservoir, which has achieved a good stimulation effect in the pilot tests. To determine what reservoir conditions are suitable to carry out volume acid fracturing, this paper firstly introduces volume acid fracturing technology by giving the stimulation mechanism and technical ideas, and initially analyzes the feasibility by the comparison of reservoir characteristics of shale gas with tight-gas carbonate. Then, this paper analyzes the validity and limitation of the volume acid fracturing technology via the analyses of control conditions for volume acid fracturing in reservoir fracturing performance, natural fracture, horizontal principal stress difference, orientation of in-situ stress and natural fracture, and gives the solution for the limitation. The study results show that the volume acid fracturing process can be used to greatly improve the flow environment of tight-gas carbonate reservoir and increase production; the incremental or stimulation response is closely related with reservoir fracturing performance, the degree of development of natural fracture, the small intersection angle between hydraulic fracture and natural fracture, the large horizontal principal stress difference is easy to form a narrow fracture zone, and it is disadvantageous to create fracture network, but the degradable fiber diversion technology may largely weaken the disadvantage. The practices indicate that the application of volume acid fracturing process to the tight-gas carbonate

Mapping Pluto's Temperature Distribution Through Twenty Years of Stellar Occultations

Science.gov (United States)

Zangari, Amanda; Binzel, R. P.; Person, M. J.

2012-10-01

Multi-chord, high signal-to-noise Pluto occultations have been observed several times over the past two decades, including events in 1988, 2002, 2006, 2007, 2010 and 2011 (Elliot et al. 1989, 2003, 2007; Person et al. 2008, 2010, 2011). We fit separate immersion and emersion occultation light-curve models to each of the individual light curves obtained from these efforts. Asymmetries in the light curves result in the half-light temperatures for opposite sides of a single chord to differ by up to 20 Kelvin in the largest case. The temperature difference for each chord is consistent using both isothermal (b=0) and non-isothermal (e.g. b=-2.2) models based on the methodology described by Elliot & Young (1992). We examine the relationship between the location of immersion and emersion points on Pluto and these temperatures at the half-light radius and will present results for correlations between these location/temperature data and surface composition maps, Pluto geometry, and accumulated insolation patterns. This work was supported by NASA Planetary Astronomy Grant to MIT (NNX10AB27G), and NSF Astronomy and Astrophysics Grant to MIT (0707609). The authors would like to acknowledge the late Professor James L. Elliot for his efforts in beginning this work. References: Elliot, J. L., Dunham, E. W., Bosh, A. S., et al. 1989, Icarus, 77,148 Elliot, J. L., Ates, A., Babcock, B. A., et al. 2003, Nature, 424,165 Elliot, J. L., Person, M. J., Gulbis, A. A. S., et al. 2007, AJ, 134, 1 Elliot, J. L., & Young, L. A. 1992, AJ, 103, 991. Person, M. J., Elliot, J. L., Gulbis, A. A. S., et al. 2008, AJ, 136, 1510 Person, M. J., Elliot, J. L., Bosh, A. S., et al. 2010, Bulletin of the American Astronomical Society, 42, 983 Person, M. J., Dunham, E. W., Bida, T., et al. 2011, EPSC-DPS Joint Meeting 2011, 1374.

Colorectal cancer mortality 10 years after a single round of guaiac faecal occult blood test (gFOBT) screening

DEFF Research Database (Denmark)

Bjerrum, Andreas; Andersen, Ole; Fischer, Anders

2016-01-01

BACKGROUND: In Denmark, colorectal cancer (CRC) is the third most frequent cancer. Randomised trials have shown that guaiac faecal occult blood test (gFOBT) screening can reduce CRC mortality, but a recent large randomised study from Finland did not find any effect. A feasibility study was carried...

Greater trochanteric fracture with occult intertrochanteric extension.

Science.gov (United States)

Reiter, Michael; O'Brien, Seth D; Bui-Mansfield, Liem T; Alderete, Joseph

2013-10-01

Proximal femoral fractures are frequently encountered in the emergency department (ED). Prompt diagnosis is paramount as delay will exacerbate the already poor outcomes associated with these injuries. In cases where radiography is negative but clinical suspicion remains high, magnetic resonance imaging (MRI) is the study of choice as it has the capability to depict fractures which are occult on other imaging modalities. Awareness of a particular subset of proximal femoral fractures, namely greater trochanteric fractures, is vital for both radiologists and clinicians since it has been well documented that they invariably have an intertrochanteric component which may require surgical management. The detection of intertrochanteric or cervical extension of greater trochanteric fractures has been described utilizing MRI but is underestimated with both computed tomography (CT) and bone scan. Therefore, if MRI is unavailable or contraindicated, the diagnosis of an isolated greater trochanteric fracture should be met with caution. The importance of avoiding this potential pitfall is demonstrated in the following case of an elderly woman with hip pain and CT demonstrating an isolated greater trochanteric fracture who subsequently returned to the ED with a displaced intertrochanteric fracture.

Are you afraid of the dark? Notes on the psychology of belief in histories of science and the occult

Science.gov (United States)

Sommer, Andreas

2016-01-01

Abstract The popular view of the inherent conflict between science and the occult has been rendered obsolete by recent advances in the history of science. Yet, these historiographical revisions have gone unnoticed in the public understanding of science and public education at large. Particularly, reconstructions of the formation of modern psychology and its links to psychical research can show that the standard view of the latter as motivated by metaphysical bias fails to stand up to scrutiny. After highlighting certain basic methodological maxims shared by psychotherapists and historians, I will try to counterbalance simplistic claims of a ‘need to believe’ as a precondition of scientific open-mindedness regarding the occurrence of parapsychological phenomena by discussing instances revealing a presumably widespread ‘will to disbelieve’ in the occult. I shall argue that generalized psychological explanations are only helpful in our understanding of history if we apply them in a symmetrical manner. PMID:27226762

Radiosensitive orbital metastasis as presentation of occult colonic adenocarcinoma.

Science.gov (United States)

Ludmir, Ethan B; McCall, Shannon J; Czito, Brian G; Palta, Manisha

2014-09-19

An 82-year-old man presented with progressive right frontal headaches. The patient's history was significant for benign polyps on surveillance colonoscopy 2 years prior, without high-grade dysplasia or carcinoma. MRI revealed an enhancing lesion arising within the superomedial aspect of the right orbit. Lesion biopsy demonstrated histological appearance and immunophenotype suggestive of colonic adenocarcinoma. Staging positron emission tomography/CT showed visceral metastases and diffuse activity in the posterior rectosigmoid, consistent with metastatic colon cancer. Treatment of the orbital lesion with external beam radiotherapy to 30 Gy resulted in significant palliation of the patient's headaches. The patient expired 2 months following treatment completion due to disease progression. Orbital metastasis as the initial presentation of an occult colorectal primary lesion is exceedingly rare, and occurred in this patient despite surveillance colonoscopy. Radiotherapy remains an efficacious modality for treatment of orbital metastases. 2014 BMJ Publishing Group Ltd.

Is repair of the protruded meninges sufficient for treatment of meningocele?

Science.gov (United States)

Yun-Hai, Song; Nan, Bao; Ping-Ping, Gao; Bo, Yang; Cheng, Chen

2015-11-01

The present study aimed to investigate the relationship between meningocele and tethered cord syndrome, diagnosis of meningocele associated with tethered cord syndrome, and when to perform surgery and the best surgical procedure. Sixty-nine children with meningocele who were admitted to Shanghai Children's Medical Center were analyzed. The relationship between meningocele and other lesions causing tethered cord syndrome was studied by combining magnetic resonance imaging (MRI) and intraoperative findings. The MRI results and intraoperative findings showed that 67 children (97%) had associated lesions such as tight filum terminale, fibrous band tethering, spinal cord or cauda equina adhesion, diastematomyelia, arachnoid cyst, and epidermoid cyst. The protruded meninges were repaired, and the intraspinal lesions were treated at the same time. Also, the tethered spinal cord was released. No neurological injuries were observed after surgery. The rate of meningocele associated with tethered cord syndrome is very high. MRI is necessary for the diagnosis of meningocele. Active surgical treatment is recommended immediately after definite diagnosis. During surgery, the surgeon should not only repair the protruded meninges but also explore the spinal canal and release the tethered cord.

Spinal dysraphism: a review of neuroradiological features with embryological correlations and proposal for a new classification

International Nuclear Information System (INIS)

Tortori-Donati, P.; Rossi, A.; Cama, A.

2000-01-01

Our purpose was to review the neuroradiological features of spinal dysraphism and to correlate them with clinical findings and up-to-date embryological theory. We also aimed to formulate a working classification which might prove useful in clinical practice. We reviewed series of 986 children referred to our Spina Bifida Centre in the past 24 years. There were 353 children with open spinal (OSD) and 633 with closed (skin-covered) spinal (CSD) dysraphism. By far the most common open abnormality was myelomeningocele, and all patients with OSD had a Chiari II malformation. CSD was categorised clinically, depending on the presence of a subcutaneous mass in the back. CSD with a mass mainly consisted of lipomas with dural defects and meningoceles, and accounted for 18.8 % of CSD. CSD without a mass were simple (tight filum terminale, intradural lipoma) or complex (split cord malformations, caudal regression). Our suggested classification is easy to use and to remember and takes into account clinical and MRI features; we have found it useful and reliable when making a preoperative neuroradiological diagnosis in clinical practice. (orig.)

A tightly coupled scheme for neutronics and thermal–hydraulics using open-source software

International Nuclear Information System (INIS)

Wu, Hsingtzu; Rizwan-uddin

2016-01-01

Highlights: • A novel tight coupling scheme called “the Integrated Tight Coupling (ITC) method” is proposed. • The ITC method is implemented using DRAGON and OpenFOAM. • The ITC method is verified using a 1.5-D example. - Abstract: Coupling neutronic and thermal–hydraulic analyses of a nuclear reactor core is important because it helps identify the most relevant safety issues without conservative assumptions. Currently coupled computations solve the same governing equations using different coupling methods, which can be sorted into two categories: loose coupling and tight coupling. This paper proposes and verifies a third coupling approach called “the Integrated Tight Coupling (ITC) method”. The mathematical equations in the nuclear fuel are rearranged to be integrated via a novel concept of the energy-group function. In addition, the data from the neutron cross section library can be used directly. The ITC method is implemented using two open-source codes: the DRAGON code and OpenFOAM. Additionally, a coupled computation using these two codes is new and has not been done. The ITC method is verified using a 1.5-D (1-D neutronics and 2-D thermal–hydraulics) symmetric unit cell example. The mesh of the tightly integrated computation is 25% coarser than the loosely coupled one. Starting from a similar initial guess, the number of iterations for the ITC method is 24% fewer than that for the loosely coupled computation to reach the same accuracy. In addition, the ITC method is tested with different initial guesses. For all cases tested, the scheme converged to the same solution. With further improvement and additional testing, the ITC method has the potential to be incorporated with other neutronics and thermal–hydraulics codes.

Installation of the light tight cover for the SSD modules (the modules are behind the aluminium plate). The silicon sensors are sensitive to light tight, so ambient light will increase the noise and may even damage them.

CERN Multimedia

Nooren, G.

2004-01-01

Installation of the light tight cover for the SSD modules (the modules are behind the aluminium plate). The silicon sensors are sensitive to light tight , so ambient light will increase the noise and may even damage them.

Dielectric constant of graphene-on-polarized substrate: A tight ...

Indian Academy of Sciences (India)

Sivabrata Sahu

Corresponding author. E-mail: gcr@iopb.res.in. Published online 24 June 2017. Abstract. We report here a microscopic tight-binding theoretical study of the dynamic dielectric response of graphene-on-polarizable substrate with impurity. The Hamiltonian consists of first, second and third nearest- neighbour electron hopping ...

Tight-binding tunneling amplitude of an optical lattice

Science.gov (United States)

Arzamasovs, Maksims; Liu, Bo

2017-11-01

The particle in a periodic potential is an important topic in an undergraduate quantum mechanics curriculum and a stepping stone on the way to more advanced topics, such as courses on interacting electrons in crystalline solids, and graduate-level research in solid-state and condensed matter physics. The interacting many-body phenomena are usually described in terms of the second quantized lattice Hamiltonians which treat single-particle physics on the level of tight-binding approximation and add interactions on top of it. The aim of this paper is to show how the tight-binding tunneling amplitude can be related to the strength of the periodic potential for the case of a cosine potential used in the burgeoning field of ultracold atoms. We show how to approach the problem of computing the tunneling amplitude of a deep lattice using the JWKB (Jeffreys-Wentzel-Kramers-Brillouin, also known as semiclassical) approximation. We also point out that care should be taken when applying the method of the linear combination of atomic orbitals (LCAO) in an optical lattice context. A summary of the exact solution in terms of Mathieu functions is also given.

Tight-binding tunneling amplitude of an optical lattice

International Nuclear Information System (INIS)

Arzamasovs, Maksims; Liu, Bo

2017-01-01

The particle in a periodic potential is an important topic in an undergraduate quantum mechanics curriculum and a stepping stone on the way to more advanced topics, such as courses on interacting electrons in crystalline solids, and graduate-level research in solid-state and condensed matter physics. The interacting many-body phenomena are usually described in terms of the second quantized lattice Hamiltonians which treat single-particle physics on the level of tight-binding approximation and add interactions on top of it. The aim of this paper is to show how the tight-binding tunneling amplitude can be related to the strength of the periodic potential for the case of a cosine potential used in the burgeoning field of ultracold atoms. We show how to approach the problem of computing the tunneling amplitude of a deep lattice using the JWKB (Jeffreys–Wentzel–Kramers–Brillouin, also known as semiclassical) approximation. We also point out that care should be taken when applying the method of the linear combination of atomic orbitals (LCAO) in an optical lattice context. A summary of the exact solution in terms of Mathieu functions is also given. (paper)

Changes in intestinal tight junction permeability associated with industrial food additives explain the rising incidence of autoimmune disease.

Science.gov (United States)

Lerner, Aaron; Matthias, Torsten

2015-06-01

The incidence of autoimmune diseases is increasing along with the expansion of industrial food processing and food additive consumption. The intestinal epithelial barrier, with its intercellular tight junction, controls the equilibrium between tolerance and immunity to non-self-antigens. As a result, particular attention is being placed on the role of tight junction dysfunction in the pathogenesis of AD. Tight junction leakage is enhanced by many luminal components, commonly used industrial food additives being some of them. Glucose, salt, emulsifiers, organic solvents, gluten, microbial transglutaminase, and nanoparticles are extensively and increasingly used by the food industry, claim the manufacturers, to improve the qualities of food. However, all of the aforementioned additives increase intestinal permeability by breaching the integrity of tight junction paracellular transfer. In fact, tight junction dysfunction is common in multiple autoimmune diseases and the central part played by the tight junction in autoimmune diseases pathogenesis is extensively described. It is hypothesized that commonly used industrial food additives abrogate human epithelial barrier function, thus, increasing intestinal permeability through the opened tight junction, resulting in entry of foreign immunogenic antigens and activation of the autoimmune cascade. Future research on food additives exposure-intestinal permeability-autoimmunity interplay will enhance our knowledge of the common mechanisms associated with autoimmune progression. Copyright © 2015. Published by Elsevier B.V.

ACUTE ZONAL OCCULT OUTER RETINOPATHY: Structural and Functional Analysis Across the Transition Zone Between Healthy and Diseased Retina.

Science.gov (United States)

Duncker, Tobias; Lee, Winston; Jiang, Fan; Ramachandran, Rithambara; Hood, Donald C; Tsang, Stephen H; Sparrow, Janet R; Greenstein, Vivienne C

2018-01-01

To assess structure and function across the transition zone (TZ) between relatively healthy and diseased retina in acute zonal occult outer retinopathy. Six patients (6 eyes; age 22-71 years) with acute zonal occult outer retinopathy were studied. Spectral-domain optical coherence tomography, fundus autofluorescence, near-infrared reflectance, color fundus photography, and fundus perimetry were performed and images were registered to each other. The retinal layers of the spectral-domain optical coherence tomography scans were segmented and the thicknesses of two outer retinal layers, that is, the total receptor and outer segment plus layers, and the retinal nerve fiber layer were measured. All eyes showed a TZ on multimodal imaging. On spectral-domain optical coherence tomography, the TZ was in the nasal retina at varying distances from the fovea. For all eyes, it was associated with loss of the ellipsoid zone band, significant thinning of the two outer retinal layers, and in three eyes with thickening of the retinal nerve fiber layer. On fundus autofluorescence, all eyes had a clearly demarcated peripapillary area of abnormal fundus autofluorescence delimited by a border of high autofluorescence; the latter was associated with loss of the ellipsoid zone band and with a change from relatively normal to markedly decreased or nonrecordable visual sensitivity on fundus perimetry. The results of multimodal imaging clarified the TZ in acute zonal occult outer retinopathy. The TZ was outlined by a distinct high autofluorescence border that correlated with loss of the ellipsoid zone band on spectral-domain optical coherence tomography. However, in fundus areas that seemed healthy on fundus autofluorescence, thinning of the outer retinal layers and thickening of the retinal nerve fiber layer were observed near the TZ. The TZ was also characterized by a decrease in visual sensitivity.

Well test mathematical model for fractures network in tight oil reservoirs

Science.gov (United States)

Diwu, Pengxiang; Liu, Tongjing; Jiang, Baoyi; Wang, Rui; Yang, Peidie; Yang, Jiping; Wang, Zhaoming

2018-02-01

Well test, especially build-up test, has been applied widely in the development of tight oil reservoirs, since it is the only available low cost way to directly quantify flow ability and formation heterogeneity parameters. However, because of the fractures network near wellbore, generated from artificial fracturing linking up natural factures, traditional infinite and finite conductivity fracture models usually result in significantly deviation in field application. In this work, considering the random distribution of natural fractures, physical model of fractures network is proposed, and it shows a composite model feature in the large scale. Consequently, a nonhomogeneous composite mathematical model is established with threshold pressure gradient. To solve this model semi-analytically, we proposed a solution approach including Laplace transform and virtual argument Bessel function, and this method is verified by comparing with existing analytical solution. The matching data of typical type curves generated from semi-analytical solution indicates that the proposed physical and mathematical model can describe the type curves characteristic in typical tight oil reservoirs, which have up warping in late-term rather than parallel lines with slope 1/2 or 1/4. It means the composite model could be used into pressure interpretation of artificial fracturing wells in tight oil reservoir.

OPTIMIZATION OF INFILL DRILLING IN NATURALLY-FRACTURED TIGHT-GAS RESERVOIRS

Energy Technology Data Exchange (ETDEWEB)

Lawrence W. Teufel; Her-Yuan Chen; Thomas W. Engler; Bruce Hart

2004-05-01

A major goal of industry and the U.S. Department of Energy (DOE) fossil energy program is to increase gas reserves in tight-gas reservoirs. Infill drilling and hydraulic fracture stimulation in these reservoirs are important reservoir management strategies to increase production and reserves. Phase II of this DOE/cooperative industry project focused on optimization of infill drilling and evaluation of hydraulic fracturing in naturally-fractured tight-gas reservoirs. The cooperative project involved multidisciplinary reservoir characterization and simulation studies to determine infill well potential in the Mesaverde and Dakota sandstone formations at selected areas in the San Juan Basin of northwestern New Mexico. This work used the methodology and approach developed in Phase I. Integrated reservoir description and hydraulic fracture treatment analyses were also conducted in the Pecos Slope Abo tight-gas reservoir in southeastern New Mexico and the Lewis Shale in the San Juan Basin. This study has demonstrated a methodology to (1) describe reservoir heterogeneities and natural fracture systems, (2) determine reservoir permeability and permeability anisotropy, (3) define the elliptical drainage area and recoverable gas for existing wells, (4) determine the optimal location and number of new in-fill wells to maximize economic recovery, (5) forecast the increase in total cumulative gas production from infill drilling, and (6) evaluate hydraulic fracture simulation treatments and their impact on well drainage area and infill well potential. Industry partners during the course of this five-year project included BP, Burlington Resources, ConocoPhillips, and Williams.

Sit-Tight Syndrome and Tenure Elongation in African Politics ...

African Journals Online (AJOL)

The post-independence politics of African countries has been dominated by the phenomenon of sit-tight African heads of state and government who had acceeded to office by election or coup d'etat. This paper examines this recurring problem in post-independence African politics by examining its general and specific ...

Loose and Tight GNSS/INS Integrations: Comparison of Performance Assessed in Real Urban Scenarios.

Science.gov (United States)

Falco, Gianluca; Pini, Marco; Marucco, Gianluca

2017-01-29

Global Navigation Satellite Systems (GNSSs) remain the principal mean of positioning in many applications and systems, but in several types of environment, the performance of standalone receivers is degraded. Although many works show the benefits of the integration between GNSS and Inertial Navigation Systems (INSs), tightly-coupled architectures are mainly implemented in professional devices and are based on high-grade Inertial Measurement Units (IMUs). This paper investigates the performance improvements enabled by the tight integration, using low-cost sensors and a mass-market GNSS receiver. Performance is assessed through a series of tests carried out in real urban scenarios and is compared against commercial modules, operating in standalone mode or featuring loosely-coupled integrations. The paper describes the developed tight-integration algorithms with a terse mathematical model and assesses their efficacy from a practical perspective.

Learning better deep features for the prediction of occult invasive disease in ductal carcinoma in situ through transfer learning

Science.gov (United States)

Shi, Bibo; Hou, Rui; Mazurowski, Maciej A.; Grimm, Lars J.; Ren, Yinhao; Marks, Jeffrey R.; King, Lorraine M.; Maley, Carlo C.; Hwang, E. Shelley; Lo, Joseph Y.

2018-02-01

Purpose: To determine whether domain transfer learning can improve the performance of deep features extracted from digital mammograms using a pre-trained deep convolutional neural network (CNN) in the prediction of occult invasive disease for patients with ductal carcinoma in situ (DCIS) on core needle biopsy. Method: In this study, we collected digital mammography magnification views for 140 patients with DCIS at biopsy, 35 of which were subsequently upstaged to invasive cancer. We utilized a deep CNN model that was pre-trained on two natural image data sets (ImageNet and DTD) and one mammographic data set (INbreast) as the feature extractor, hypothesizing that these data sets are increasingly more similar to our target task and will lead to better representations of deep features to describe DCIS lesions. Through a statistical pooling strategy, three sets of deep features were extracted using the CNNs at different levels of convolutional layers from the lesion areas. A logistic regression classifier was then trained to predict which tumors contain occult invasive disease. The generalization performance was assessed and compared using repeated random sub-sampling validation and receiver operating characteristic (ROC) curve analysis. Result: The best performance of deep features was from CNN model pre-trained on INbreast, and the proposed classifier using this set of deep features was able to achieve a median classification performance of ROC-AUC equal to 0.75, which is significantly better (p<=0.05) than the performance of deep features extracted using ImageNet data set (ROCAUC = 0.68). Conclusion: Transfer learning is helpful for learning a better representation of deep features, and improves the prediction of occult invasive disease in DCIS.

Breast conservation in the setting of contemporary multimodality treatment provides excellent outcomes for patients with occult primary breast cancer.

Science.gov (United States)

Rueth, Natasha M; Black, Dalliah M; Limmer, Angela R; Gabriel, Emmanuel; Huo, Lei; Fornage, Bruno D; Dogan, Basak E; Chavez-MacGregor, Mariana; Yi, Min; Hunt, Kelly K; Strom, Eric A

2015-01-01

To evaluate recurrence and survival for patients with occult (T0N+) breast cancer who underwent contemporary treatment, assessing outcomes for breast conservation and mastectomy. We performed a single-institution review of women with occult breast cancer presenting with axillary metastasis without identifiable breast tumor or distant metastasis. We excluded patients with tumors in the axillary tail or mastectomy specimen, patients with additional nonbreast cancer diagnoses, and patients with a history of breast cancer. Breast conservation was defined as axillary node dissection with radiation therapy, without breast surgery. We evaluated patient, tumor, treatment, and outcome variables. Patients were assessed for local, regional, and distant recurrences. Overall survival was calculated using the Kaplan-Meier method. Thirty-six patients met criteria for occult breast cancer. Most of these patients (77.8 %) had N1 disease. Fifty percent of cancers (n = 18) were estrogen receptor-positive; 12 (33.3 %) were triple-negative. All patients were evaluated with mammography. Thirty-five patients had breast ultrasound (97.2 %) and 33 (91.7 %) had an MRI. Thirty-four patients (94.4 %) were treated with chemotherapy and 33 (91.7 %) with radiotherapy. Twenty-seven patients (75.0 %) were treated with breast conservation. The median follow-up was 64 months. There were no local or regional failures. One distant recurrence occurred >5 years after diagnosis, resulting in a 5-years overall survival rate of 100 %. There were no significant survival differences between patients receiving breast conservation versus mastectomy (p = 0.7). Breast conservation-performed with contemporary imaging and multimodality treatment-provides excellent local control and survival for women with T0N+ breast cancer and can be safely offered instead of mastectomy.

Poster 7: Could PAH or HAC explain the Titan's stratosphere absorption around 3.4 µm revealed by solar occultations?

Science.gov (United States)

Cordier, Daniel; Cours, Thibaud; Rey, Michael; Maltagliati, Luca; Seignovert, Benoit; Biennier, Ludovic

2016-06-01

In 2006, during Cassini's 10th flyby of Titan (T10), Bellucci et al. (2009) observed a solar occultation by Titan's atmosphere through the solar port of the Cassini/VIMS instrument. These authors noticed the existence of an unexplained additional absorption superimposed to the CH4 3.3 µm band. Because they were unable to model this absorption with gases, they attributed this intriguing feature to the signature of solid state organic components. Kim et al. (2011) revisited the data collected by Bellucci et al. (2009) and they considered the possible contribution of aerosols formed by hydrocarbon ices. They specifically took into account C2H6, CH4, CH3CN, C5H12 and C6H12 ices. More recently, Maltagliati et al. (2015) analyzed a set of four VIMS solar occultations, corresponding to flybys performed between January 2006 and September 2011 at different latitudes. They confirmed the presence of the 3.3 µm absorption in all occultations and underlined the possible importance of gaseous ethane, which has a strong plateau of absorption lines in that wavelength range.In this work, we show that neither hydrocarbon ices nor molecular C2H6 cannot satisfactorily explain the observed absorption. Our simulations speak in favor of an absorption due to the presence of PAH molecules or HAC in the stratosphere of Titan. PAH have been already considered by Lopes-Puertas et al. (2013) at altitudes larger than ˜900 km and tentatively identified in the stratosphere by Maltagliati et al. (2015); PAH and HAC are good candidates for Titan's aerosols precursors.

Relevant multi-setting tight Bell inequalities for qubits and qutrits

International Nuclear Information System (INIS)

Deng Dongling; Zhou Zisui; Chen Jingling

2009-01-01

In the celebrated paper [D. Collins, N. Gisin, J. Phys. A Math. Gen. 37 (2004) 1775], Collins and Gisin presented for the first time a three-setting Bell inequality (here we call it CG inequality for simplicity) which is relevant to the Clauser-Horne-Shimony-Holt (CHSH) inequality. Inspired by their brilliant ideas, we obtained some multi-setting tight Bell inequalities, which are relevant to the CHSH inequality and the CG inequality. Moreover, we generalized the method in the paper [J.L. Chen, D.L. Deng, Phys. Rev. A 79 (2009) 012115] to construct Bell inequality for qubits to higher dimensional system. Based on the generalized method, we present, for the first time, a three-setting tight Bell inequality for two qutrits, which is maximally violated by nonmaximally entangled states and relevant to the Collins-Gisin-Linden-Massar-Popescu inequality.

Outcome analysis of salvage radiotherapy for occult cervical cancer found after simple hysterectomy

International Nuclear Information System (INIS)

Koh, Hyeon-Kang; Jeon, Wan; Kim, Hak-Jae; Wu, Hong-Gyun; Kim, Kyubo; Chie, Eui-Kyu; Ha, Sung-W.

2013-01-01

The objective was to analyze the outcomes of the patients, who received salvage radiotherapy for incidentally discovered cervical cancer following simple hysterectomy, and to identify the influence of intracavitary radiotherapy on treatment outcomes. Data from 117 patients with occult cervical cancer who underwent simple hysterectomy followed by salvage radiotherapy from September 1979 to November 2010 were collected. All the patients received external beam radiotherapy with (n=45) or without (n=72) intracavitary radiotherapy. Local control, disease-free survival, overall survival and treatment-related toxicity were investigated. The median follow-up time was 75 months. The 5- and 10-year local control/disease-free survival/overall survival rates were 93/87/87% and 90/84/83%, respectively. Among 98 patients who had no residual disease and negative resection margin on surgical specimens, 32 (33%) received intracavitary radiotherapy and 66 (67%) did not. There were no differences in patient and tumor characteristics between patients treated with and without intracavitary radiotherapy. The 5-year local control rate for the non-intracavitary radiotherapy group was 93 versus 94% for the intracavitary radiotherapy group (P=0.564); the disease-free survival rate was 88 versus 94% (P=0.894); the overall survival rate was 95 versus 85% (P=0.106), respectively. Among all patients, there were 5% of Grade 3 or higher late toxicities. Patients with occult invasive cervical cancer discovered following simple hysterectomy could be treated safely and effectively with salvage radiotherapy. For patients with no residual disease and negative resection margin, intracavitary radiotherapy could be omitted. (author)

Modulation of Tight Junction Structure and Function by Kinases and Phosphatases Targeting Occludin

Directory of Open Access Journals (Sweden)

Max Johannes Dörfel

2012-01-01

Full Text Available Tight junctions (TJs typically represent the most apical contacts in epithelial and endothelial cell layers where they play an essential role in the separation of extracellular or luminal spaces from underlying tissues in the body. Depending on the protein composition, TJs define the barrier characteristics and in addition maintain cell polarity. Two major families of integral membrane proteins form the typical TJ strand network, the tight junction-associated MARVEL protein (TAMP family members occludin, tricellulin, and MarvelD3 as well as a specific set of claudins. Occludin was the first identified member of these tetraspanins and is now widely accepted as a regulator of TJ assembly and function. Therefore, occludin itself has to be tightly regulated. Phosphorylation of occludin appears to be of central importance in this context. Here we want to summarize current knowledge on the kinases and phosphatases directly modifying occludin, and their role in the regulation of TJ structure, function, and dynamics.

Prediction of Gas Leak Tightness of Superplastically Formed Products

NARCIS (Netherlands)

Snippe, Q.H.C.; Meinders, Vincent T.; Barlat, F; Moon, Y.H.; Lee, M.G.

2010-01-01

In some applications, in this case an aluminium box in a subatomic particle detector containing highly sensitive detecting devices, it is important that a formed sheet should show no gas leak from one side to the other. In order to prevent a trial-and-error procedure to make this leak tight box, a

Unusual Case of Occult Brucella Osteomyelitis in the Skull Detected by Bone Scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Sohn, Myung Hee; Lim, Seok Tae; Jeong, Young Jin; Kim, Dong Wook; Jeong, Hwan Jeong; Lee, Chang Seob [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

2010-06-15

Brucellosis is a worldwide infectious disease of animals that can be transmitted to humans. Osteoarticular involvement is the most common complication of brucellosis. A 47-year-old man, who was a stock breeder, complained of myalgia with fever and chills for 2 weeks. The serology titers and blood cultures for brucellosis were positive. Bone scintigraphy demonstrated a focally increased uptake in the left supra orbital area. Plain radiographs showed an osteolytic lesion, and an MRI revealed signal abnormalities in the corresponding site. We present an unusual case of occult Brucella osteomyelitis in the frontal bone of the skull detected by done scintigraphy.

Unusual Case of Occult Brucella Osteomyelitis in the Skull Detected by Bone Scintigraphy

International Nuclear Information System (INIS)

Sohn, Myung Hee; Lim, Seok Tae; Jeong, Young Jin; Kim, Dong Wook; Jeong, Hwan Jeong; Lee, Chang Seob

2010-01-01

Brucellosis is a worldwide infectious disease of animals that can be transmitted to humans. Osteoarticular involvement is the most common complication of brucellosis. A 47-year-old man, who was a stock breeder, complained of myalgia with fever and chills for 2 weeks. The serology titers and blood cultures for brucellosis were positive. Bone scintigraphy demonstrated a focally increased uptake in the left supra orbital area. Plain radiographs showed an osteolytic lesion, and an MRI revealed signal abnormalities in the corresponding site. We present an unusual case of occult Brucella osteomyelitis in the frontal bone of the skull detected by done scintigraphy.

Diagnosing the tight building syndrome

Energy Technology Data Exchange (ETDEWEB)

Rogers, S.A.

1987-12-01

Formaldehyde is but one of many chemicals capable of causing the tight building syndrome or environmentally induced illness (EI). The spectrum of symptoms it may induce includes attacks of headache, flushing, laryngitis, dizziness, nausea, extreme weakness, arthralgia, unwarranted depression, dysphonia, exhaustion, inability to think clearly, arrhythmia or muscle spasms. The nonspecificity of such symptoms can baffle physicians from many specialties. Presented herein is a simple office method for demonstrating that formaldehyde is among the etiologic agents triggering these symptoms. The very symptoms that patients complain of can be provoked within minutes, and subsequently abolished, with an intradermal injection of the appropriate strength of formaldehyde. This injection aids in convincing the patient of the cause of the symptoms so he can initiate measure to bring his disease under control.

CHARACTERIZATION OF TIGHTLY-ASSOCIATED SMOOTH MUSCLE MYOSIN-MYOSIN LIGHT CHAIN KINASE-CALMODULIN COMPLEXES*

OpenAIRE

Hong, Feng; Haldeman, Brian D.; John, Olivia A.; Brewer, Paul D.; Wu, Yi-Ying; Ni, Shaowei; Wilson, David P.; Walsh, Michael P.; Baker, Jonathan E.; Cremo, Christine R.

2009-01-01

A current popular model to explain phosphorylation of smooth muscle myosin (SMM) by smooth muscle myosin light chain kinase (MLCK) proposes that MLCK is bound tightly to actin but weakly to SMM. We found that MLCK and calmodulin (CaM) co-purify with unphosphorylated SMM (up-SMM) from chicken gizzard, suggesting that they are tightly bound. Although the MLCK:SMM molar ratio in SMM preparations was well below stoichiometric (1:73 ± 9), the ratio was ~ 23–37% of that in gizzard tissue. Fifteen t...

FDTD approach to optical forces of tightly focused vector beams on metal particles.

Science.gov (United States)

Qin, Jian-Qi; Wang, Xi-Lin; Jia, Ding; Chen, Jing; Fan, Ya-Xian; Ding, Jianping; Wang, Hui-Tian

2009-05-11

We propose an improved FDTD method to calculate the optical forces of tightly focused beams on microscopic metal particles. Comparison study on different kinds of tightly focused beams indicates that trapping efficiency can be altered by adjusting the polarization of the incident field. The results also show the size-dependence of trapping forces exerted on metal particles. Transverse tapping forces produced by different illumination wavelengths are also evaluated. The numeric simulation demonstrates the possibility of trapping moderate-sized metal particles whose radii are comparable to wavelength.

Jack-knife stretching promotes flexibility of tight hamstrings after 4 weeks: a pilot study.

Science.gov (United States)

Sairyo, Koichi; Kawamura, Takeshi; Mase, Yasuyoshi; Hada, Yasushi; Sakai, Toshinori; Hasebe, Kiyotaka; Dezawa, Akira

2013-08-01

Tight hamstrings are reported to be one of the causes of low back pain. However, there have been few reports on effective stretching procedures for the tight hamstrings. The so-called jack-knife stretch, an active-static type of stretching, can efficiently increase the flexibility of tight hamstrings. To evaluate hamstring tightness before and after the 4-week stretching protocol in healthy volunteer adults and patients aged under 18 years with low back pain. For understanding the hamstrings tightness, we measured two parameters including (1) finger to floor distance (FFD) and (2) pelvis forward inclination angle (PFIA). Eight healthy adult volunteers who had no lumbar or hip problems participated in this study (mean age: 26.8 years). All lacked flexibility and their FFD were positive before the experiment. Subjects performed 2 sets of the jack-knife stretch every day for 4 weeks. One set consisted of 5 repetitions, each held for 5 s. Before and during the 4-week experiment, the FFD and PFIA of toe-touching tests were measured weekly. For 17 of the sports players aged under 18, only FFD was measured. In adult volunteers, FFD was 14.1 ± 6.1 cm before the experiment and decreased to -8.1 ± 3.7 cm by the end of week 4, indicating a gain in flexibility of 22.2 cm. PFIA was 50.6 ± 8.2 before the experiment and 83.8 ± 5.8 degrees after. Before and after the experiment, the differences were significant (p hamstrings.

Overt and occult vidian canal involvement in juvenile angiofibroma and its possible impact on recurrence.

Science.gov (United States)

Thakar, Alok; Hota, Ashutosh; Bhalla, Ashu Seth; Gupta, Siddharth Datta; Sarkar, Chitra; Kumar, Rakesh

2016-04-01

Postexcision residual disease in the vidian canal is speculated to contribute to recurrence in juvenile angiofibroma. We composed a prospective cohort of 16 consecutive patients with juvenile angiofibroma (stages IIA-IIIB). The presurgical vidian canal assessment was done by contrast-enhanced CT (1.2 mm collimation). At surgery after complete tumor excision, the vidian canal tissue was sampled for histology. Postexcision drilling of the vidian canal was done in 8 of 15 patients to remove microscopic residual disease, with a 24 to 48 month follow-up period. Presurgical radiology indicated ipsilateral vidian canal enlargement (≥3 mm)/destruction in 13 of 16 patients. Radiologically occult involvement was documented only by histology in another 1 of 16 patients. Postexcision sampling of the vidian canal noted microscopic residual tumor in 3 of 15 patients. No recurrences were noted in 8 cases (0 of 8) with postexcision drilling of the vidian canal and 2 recurrences in 7 cases (2 of 7) with no drilling (p = .20). Vidian canal involvement in juvenile angiofibroma is almost universal (14 of 16) and may be occult to CT evaluation. The site may harbor microscopic residual tumor after seemingly complete excision. Surgical attention toward it may reduce recurrences. © 2015 Wiley Periodicals, Inc. Head Neck 38: E421-425, 2016. © 2015 Wiley Periodicals, Inc.

Potential evaluation of CO2 storage and enhanced oil recovery of tight oil reservoir in the Ordos Basin, China.

Science.gov (United States)

Tian, Xiaofeng; Cheng, Linsong; Cao, Renyi; Zhang, Miaoyi; Guo, Qiang; Wang, Yimin; Zhang, Jian; Cui, Yu

2015-07-01

Carbon -di-oxide (CO2) is regarded as the most important greenhouse gas to accelerate climate change and ocean acidification. The Chinese government is seeking methods to reduce anthropogenic CO2 gas emission. CO2 capture and geological storage is one of the main methods. In addition, injecting CO2 is also an effective method to replenish formation energy in developing tight oil reservoirs. However, exiting methods to estimate CO2 storage capacity are all based on the material balance theory. This was absolutely correct for normal reservoirs. However, as natural fractures widely exist in tight oil reservoirs and majority of them are vertical ones, tight oil reservoirs are not close. Therefore, material balance theory is not adaptive. In the present study, a new method to calculate CO2 storage capacity is presented. The CO2 effective storage capacity, in this new method, consisted of free CO2, CO2 dissolved in oil and CO2 dissolved in water. Case studies of tight oil reservoir from Ordos Basin was conducted and it was found that due to far lower viscosity of CO2 and larger solubility in oil, CO2 could flow in tight oil reservoirs more easily. As a result, injecting CO2 in tight oil reservoirs could obviously enhance sweep efficiency by 24.5% and oil recovery efficiency by 7.5%. CO2 effective storage capacity of Chang 7 tight oil reservoir in Longdong area was 1.88 x 10(7) t. The Chang 7 tight oil reservoir in Ordos Basin was estimated to be 6.38 x 10(11) t. As tight oil reservoirs were widely distributed in Songliao Basin, Sichuan Basin and so on, geological storage capacity of CO2 in China is potential.

Strain-dependent augmentation of tight-junction barrier function in human primary epidermal keratinocytes by Lactobacillus and Bifidobacterium lysates.

Science.gov (United States)

Sultana, Reshma; McBain, Andrew J; O'Neill, Catherine A

2013-08-01

In this study, we investigated whether probiotic lysates can modify the tight-junction function of human primary keratinocytes. The keratinocytes were grown on cell culture inserts and treated with lysates from Bifidobacterium longum, Lactobacillus plantarum, Lactobacillus reuteri, Lactobacillus fermentum, or Lactobacillus rhamnosus GG. With the exception of L. fermentum (which decreased cell viability), all strains markedly enhanced tight-junction barrier function within 24 h, as assessed by measurements of transepithelial electrical resistance (TEER). However, B. longum and L. rhamnosus GG were the most efficacious, producing dose-dependent increases in resistance that were maintained for 4 days. These increases in TEER correlated with elevated expression of tight-junction protein components. Neutralization of Toll-like receptor 2 abolished both the increase in TEER and expression of tight-junction proteins induced by B. longum, but not L. rhamnosus GG. These data suggest that some bacterial strains increase tight-junction function via modulation of protein components but the different pathways involved may vary depending on the bacterial strain.

Effects of Tight Versus Non Tight Control of Metabolic Acidosis on Early Renal Function After Kidney Transplantation

Directory of Open Access Journals (Sweden)

Farhad Etezadi

2012-09-01

Full Text Available Background Recently, several studies have been conducted to determine the optimal strategy for intraoperative fluid replacement therapy in renal transplantation surgery. Since infusion of sodium bicarbonate as a buffer seems to be safer than other buffer compounds (lactate, gluconate, acetatethat indirectly convert into it within the liver, We hypothesized tight control of metabolic acidosis by infusion of sodium bicarbonate may improve early post-operative renal function in renal transplant recipients. Methods:120 patients were randomly divided into two equal groups. In group A, bicarbonate was infused intra-operatively according to Base Excess (BE measurements to achieve the normal values of BE (5 to +5 mEq/L. In group B, infusion of bicarbonate was allowed only in case of severe metabolic acidosis (BE [less than or equal to] 15 mEq/L or bicarbonate [less than or equal to] 10 mEq/L or PH [less than or equal to] 7.15. Minute ventilation was adjusted to keep PaCO2 within the normal range. Primary end-point was sampling of serum creatinine level in first, second, third and seventh post-operative days for statistical comparison between groups. Secondary objectives were comparison of cumulative urine volumes in the first 24 h of post-operative period and serum BUN levels which were obtained in first, second, third and seventh post-operative days. Results:In group A, all of consecutive serum creatinine levels were significantly lower in comparison with group B. With regard to secondary outcomes, no significant difference between groups was observed. Conclusion:Intra-operative tight control of metabolic acidosis by infusion of Sodium Bicarbonate in renal transplant recipients may improve early post-operative renal function.

Effects of tight versus non tight control of metabolic acidosis on early renal function after kidney transplantation

Directory of Open Access Journals (Sweden)

Etezadi Farhad

2012-09-01

Full Text Available Abstract Background Recently, several studies have been conducted to determine the optimal strategy for intra-operative fluid replacement therapy in renal transplantation surgery. Since infusion of sodium bicarbonate as a buffer seems to be safer than other buffer compounds (lactate, gluconate, acetatethat indirectly convert into it within the liver, We hypothesized tight control of metabolic acidosis by infusion of sodium bicarbonate may improve early post-operative renal function in renal transplant recipients. Methods 120 patients were randomly divided into two equal groups. In group A, bicarbonate was infused intra-operatively according to Base Excess (BE measurements to achieve the normal values of BE (−5 to +5 mEq/L. In group B, infusion of bicarbonate was allowed only in case of severe metabolic acidosis (BE ≤ −15 mEq/L or bicarbonate ≤ 10 mEq/L or PH ≤ 7.15. Minute ventilation was adjusted to keep PaCO2 within the normal range. Primary end-point was sampling of serum creatinine level in first, second, third and seventh post-operative days for statistical comparison between groups. Secondary objectives were comparison of cumulative urine volumes in the first 24 h of post-operative period and serum BUN levels which were obtained in first, second, third and seventh post-operative days. Results In group A, all of consecutive serum creatinine levels were significantly lower in comparison with group B. With regard to secondary outcomes, no significant difference between groups was observed. Conclusion Intra-operative tight control of metabolic acidosis by infusion of Sodium Bicarbonate in renal transplant recipients may improve early post-operative renal function.

Effect of cAMP derivates on assembly and maintenance of tight junctions in human umbilical vein endothelial cells

Directory of Open Access Journals (Sweden)

Beese Michaela

2010-09-01

Full Text Available Abstract Background Endothelial tight and adherens junctions control a variety of physiological processes like adhesion, paracellular transport of solutes or trafficking of activated leukocytes. Formation and maintenance of endothelial junctions largely depend on the microenvironment of the specific vascular bed and on interactions of the endothelium with adjacent cell types. Consequently, primary cultures of endothelial cells often lose their specific junctional pattern and fail to establish tight monolayer in vitro. This is also true for endothelial cells isolated from the vein of human umbilical cords (HUVEC which are widely used as model for endothelial cell-related studies. Results We here compared the effect of cyclic 3'-5'-adenosine monophosphate (cAMP and its derivates on formation and stabilization of tight junctions and on alterations in paracellular permeability in HUVEC. We demonstrated by light and confocal laser microscopy that for shorter time periods the sodium salt of 8-bromoadenosine-cAMP (8-Br-cAMP/Na and for longer incubation periods 8-(4-chlorophenylthio-cAMP (pCPT-cAMP exerted the greatest effects of all compounds tested here on formation of continuous tight junction strands in HUVEC. We further demonstrated that although all compounds induced protein kinase A-dependent expression of the tight junction proteins claudin-5 and occludin only pCPT-cAMP slightly enhanced paracellular barrier functions. Moreover, we showed that pCPT-cAMP and 8-Br-cAMP/Na induced expression and membrane translocation of tricellulin. Conclusions pCPT-cAMP and, to a lesser extend, 8-Br-cAMP/Na improved formation of continuous tight junction strands and decreased paracellular permeability in primary HUVEC. We concluded that under these conditions HUVEC represent a feasible in vitro model to study formation and disassembly of endothelial tight junctions and to characterize tight junction-associated proteins

The Transit Light Curve Project. VIII. Six Occultations of the Exoplanet TrES-3

OpenAIRE

Winn, Joshua N.; Holman, Matthew J.; Shporer, Avi; Fernandez, Jose; Mazeh, Tsevi; Latham, David W.; Charbonneau, David; Everett, Mark E.

2008-01-01

We present photometry of the exoplanet host star TrES-3 spanning six occultations (secondary eclipses) of its giant planet. No flux decrements were detected, leading to 99%-confidence upper limits on the planet-to-star flux ratio of 0.00024, 0.0005, and 0.00086 in the i, z, and R bands respectively. The corresponding upper limits on the planet's geometric albedo are 0.30, 0.62, and 1.07. The upper limit in the i band rules out the presence of highly reflective clouds, and is only a factor of ...

Universality of energy conversion efficiency for optimal tight-coupling heat engines and refrigerators

International Nuclear Information System (INIS)

Sheng, Shiqi; Tu, Z C

2013-01-01

A unified χ-criterion for heat devices (including heat engines and refrigerators), which is defined as the product of the energy conversion efficiency and the heat absorbed per unit time by the working substance (de Tomás et al 2012 Phys. Rev. E 85 010104), is optimized for tight-coupling heat engines and refrigerators operating between two heat baths at temperatures T c and T h ( > T c ). By taking a new convention on the thermodynamic flux related to the heat transfer between two baths, we find that for a refrigerator tightly and symmetrically coupled with two heat baths, the coefficient of performance (i.e., the energy conversion efficiency of refrigerators) at maximum χ asymptotically approaches √(ε C ) when the relative temperature difference between two heat baths ε C -1 ≡(T h -T c )/T c is sufficiently small. Correspondingly, the efficiency at maximum χ (equivalent to maximum power) for a heat engine tightly and symmetrically coupled with two heat baths is proved to be η C /2+η C 2 /8 up to the second order term of η C ≡ (T h − T c )/T h , which reverts to the universal efficiency at maximum power for tight-coupling heat engines operating between two heat baths at small temperature difference in the presence of left–right symmetry (Esposito et al 2009 Phys. Rev. Lett. 102 130602). (fast track communication)

MRI tight posterior fossa sign for prenatal diagnosis of Chiari type II malformation

Energy Technology Data Exchange (ETDEWEB)

Ando, Kumiko; Ishikura, Reiichi; Ogawa, Masayo; Takada, Yoshihiro; Yamamoto, Satoshi; Fujiwara, Masayuki; Hirota, Shozo [Hyogo College of Medicine, Department of Radiology, Nishinomiya, Hyogo (Japan); Shakudo, Miyuki [Osaka City General Hospital, Department of Radiology, Osaka (Japan); Tanaka, Hiroyuki [Hyogo College of Medicine, Department of Gynecology, Nishinomiya (Japan); Minagawa, Kyoko [Hyogo College of Medicine, Department of Pediatrics, Nishinomiya (Japan)

2007-12-15

Chiari type II malformation (CMII) is one of three hindbrain malformations that display hydrocephalus. We have observed that cerebrospinal fluid (CSF) signal in the posterior fossa, which is always apparent on normal fetal MR images, is not visible in a fetus with CMII. We use the term 'tight posterior fossa' for this MR imaging finding, and evaluate the diagnostic value of this finding on fetal MR images. Included in the study were 21 fetuses which underwent brain MR imaging at 1.5 T using two-dimensional balanced turbo-field-echo (2-D balanced-TFE) in the axial and sagittal planes. Postnatal diagnoses were CMII (n=5), CNS abnormalities other than CMII (n=8), and no abnormality (n=8). A tight posterior fossa was defined as an absent or slit-like water signal space around the hindbrain in the posterior fossa on both sagittal and axial MR images. All CMII fetuses displayed a tight posterior fossa on MR images. Hydrocephalus was visualized in all CMII fetuses and myelomeningocele in four fetuses, but hindbrain herniation was visualized only in two of five fetuses. The CSF signal surrounding the hindbrain was clearly visible in all the other 16 fetuses, including five with hydrocephalus not associated with CMII, although it was slightly narrower in a fetus with a cloverleaf skull than in the normal fetuses. Tight posterior fossa in the presence of hydrocephalus is a useful and characteristic finding of CMII on fetal MRI. (orig.)

MRI tight posterior fossa sign for prenatal diagnosis of Chiari type II malformation

International Nuclear Information System (INIS)

Ando, Kumiko; Ishikura, Reiichi; Ogawa, Masayo; Takada, Yoshihiro; Yamamoto, Satoshi; Fujiwara, Masayuki; Hirota, Shozo; Shakudo, Miyuki; Tanaka, Hiroyuki; Minagawa, Kyoko

2007-01-01

Chiari type II malformation (CMII) is one of three hindbrain malformations that display hydrocephalus. We have observed that cerebrospinal fluid (CSF) signal in the posterior fossa, which is always apparent on normal fetal MR images, is not visible in a fetus with CMII. We use the term 'tight posterior fossa' for this MR imaging finding, and evaluate the diagnostic value of this finding on fetal MR images. Included in the study were 21 fetuses which underwent brain MR imaging at 1.5 T using two-dimensional balanced turbo-field-echo (2-D balanced-TFE) in the axial and sagittal planes. Postnatal diagnoses were CMII (n=5), CNS abnormalities other than CMII (n=8), and no abnormality (n=8). A tight posterior fossa was defined as an absent or slit-like water signal space around the hindbrain in the posterior fossa on both sagittal and axial MR images. All CMII fetuses displayed a tight posterior fossa on MR images. Hydrocephalus was visualized in all CMII fetuses and myelomeningocele in four fetuses, but hindbrain herniation was visualized only in two of five fetuses. The CSF signal surrounding the hindbrain was clearly visible in all the other 16 fetuses, including five with hydrocephalus not associated with CMII, although it was slightly narrower in a fetus with a cloverleaf skull than in the normal fetuses. Tight posterior fossa in the presence of hydrocephalus is a useful and characteristic finding of CMII on fetal MRI. (orig.)

Protecting intestinal epithelial integrity by galacto-oligosaccharides: Keeping it tight

NARCIS (Netherlands)

Akbari, P.

2016-01-01

The intestinal barrier serves as a first line of host defense against potentially harmful stressors from the environment ingested with food, and is primarily formed by epithelial cells connected by tight junctions. Oligosaccharides have been identified as components in milk, particularly in

Envelopes of Sets of Measures, Tightness, and Markov Control Processes

International Nuclear Information System (INIS)

Gonzalez-Hernandez, J.; Hernandez-Lerma, O.

1999-01-01

We introduce upper and lower envelopes for sets of measures on an arbitrary topological space, which are then used to give a tightness criterion. These concepts are applied to show the existence of optimal policies for a class of Markov control processes

Letter to the EditorAbel transform inversion of radio occultation measurements made with a receiver inside the Earth’s atmosphere

Directory of Open Access Journals (Sweden)

S. B. Healy

2002-08-01

Full Text Available Radio occultation measurements made with a receiver inside the Earth’s atmosphere can be inverted, assuming local spherical symmetry, with an Abel transform to provide an estimate of the atmospheric refractive index profile. The measurement geometry is closely related to problems encountered when inverting seismic time-travel data and solar occultation measurements, where the Abel solution is well known. The method requires measuring both rays that originate from above and below the local horizon of the receiver. The Abel transform operates on a profile of "partial bending angles" found by subtracting the positive elevation measurement from the negative elevation value with the same impact parameter. In principle, the refractive index profile can be derived from measurements with a single frequency GPS receiver because the ionospheric bending is removed when the partial bending angle is evaluated.Key words. Atmospheric composition and structure (pressure, density and temperature – Radio science (remote sensing

Letter to the EditorAbel transform inversion of radio occultation measurements made with a receiver inside the Earth’s atmosphere

Directory of Open Access Journals (Sweden)

J. Haase

Full Text Available Radio occultation measurements made with a receiver inside the Earth’s atmosphere can be inverted, assuming local spherical symmetry, with an Abel transform to provide an estimate of the atmospheric refractive index profile. The measurement geometry is closely related to problems encountered when inverting seismic time-travel data and solar occultation measurements, where the Abel solution is well known. The method requires measuring both rays that originate from above and below the local horizon of the receiver. The Abel transform operates on a profile of "partial bending angles" found by subtracting the positive elevation measurement from the negative elevation value with the same impact parameter. In principle, the refractive index profile can be derived from measurements with a single frequency GPS receiver because the ionospheric bending is removed when the partial bending angle is evaluated.Key words. Atmospheric composition and structure (pressure, density and temperature – Radio science (remote sensing

Detection and identification of occult HBV in blood donors in Taiwan using a commercial, multiplex, multi-dye nucleic acid amplification technology screening test.

Science.gov (United States)

Lin, K T; Chang, C L; Tsai, M H; Lin, K S; Saldanha, J; Hung, C M

2014-02-01

The ability of a new generation commercial, multiplex, multi-dye test from Roche, the cobas TaqScreen MPX test, version 2.0, to detect and identify occult HBV infections was evaluated using routine donor samples from Kaohsiung Blood Bank, Taiwan. A total of 5973 samples were tested by nucleic acid amplification technology (NAT); 5898 in pools of six, 66 in pools of less than six and nine samples individually. NAT-reactive samples were retested with alternative NAT tests, and follow-up samples from the donors were tested individually by NAT and for all the HBV serological markers. Eight NAT-only-reactive donors were identified, and follow-up samples were obtained from six of the donors. The results indicated that all eight donors had an occult HBV infection with viral loads <12 IU/ml. The cobas(®) TaqScreen MPX test, version 2.0, has an advantage over the current Roche blood screening test, the cobas TaqScreen MPX test, for screening donations in countries with a high prevalence of occult HBV infections since the uncertainty associated with identifying samples with very low viremia is removed by the ability of the test to identify the viral target in samples that are reactive with the cobas TaqScreen MPX test, version 2.0. © 2013 International Society of Blood Transfusion.

Extended Lagrangian Density Functional Tight-Binding Molecular Dynamics for Molecules and Solids

International Nuclear Information System (INIS)

Aradi, Balint; Frauenheim, Thomas

2015-01-01

A computationally fast quantum mechanical molecular dynamics scheme using an extended Lagrangian density functional tight-binding formulation has been developed and implemented in the DFTB+ electronic structure program package for simulations of solids and molecular systems. The scheme combines the computational speed of self-consistent density functional tight-binding theory with the efficiency and long-term accuracy of extended Lagrangian Born-Oppenheimer molecular dynamics. Furthermore, for systems without self-consistent charge instabilities, only a single diagonalization or construction of the single-particle density matrix is required in each time step. The molecular dynamics simulation scheme can also be applied to a broad range of problems in materials science, chemistry, and biology

Extended Lagrangian Density Functional Tight-Binding Molecular Dynamics for Molecules and Solids.

Science.gov (United States)

Aradi, Bálint; Niklasson, Anders M N; Frauenheim, Thomas

2015-07-14

A computationally fast quantum mechanical molecular dynamics scheme using an extended Lagrangian density functional tight-binding formulation has been developed and implemented in the DFTB+ electronic structure program package for simulations of solids and molecular systems. The scheme combines the computational speed of self-consistent density functional tight-binding theory with the efficiency and long-term accuracy of extended Lagrangian Born-Oppenheimer molecular dynamics. For systems without self-consistent charge instabilities, only a single diagonalization or construction of the single-particle density matrix is required in each time step. The molecular dynamics simulation scheme can be applied to a broad range of problems in materials science, chemistry, and biology.

Goethe’s theory of colors between the ancient philosophy, middle ages occultism and modern science

Directory of Open Access Journals (Sweden)

Victor Barsan

2016-12-01

Full Text Available Goethe’s rejection of Newton’s theory of colors is an interesting example of the vulnerability of the human mind—however brilliant it might be—to fanaticism. After an analysis of Goethe’s persistent fascination with magic and occultism, of his education, existential experiences, influences, and idiosyncrasies, the authors propose an original interpretation of his anti-Newtonian position. The relevance of Goethe’s Farbenlehre to physics and physiology, from the perspective of modern science, is discussed in detail.

Analysis of macular cone photoreceptors in a case of occult macular dystrophy

Directory of Open Access Journals (Sweden)

Tojo N

2013-05-01

Full Text Available Naoki Tojo Tomoko Nakamura Hironori Ozaki Miyako Oka Toshihiko Oiwake Atsushi HayashiDepartment of Ophthalmology, University of Toyama, Toyama, JapanPurpose: To investigate changes in cone photoreceptors with adaptive optics (AO fundus imaging and spectral domain optical coherence tomography (SD-OCT in a case of occult macular dystrophy (OMD.Patient and methods: Both eyes of a 42-year-old woman diagnosed with OMD were examined. We used an AO fundus camera to obtain images of cone photoreceptors in the macula of the OMD subject and five healthy control subjects. Correlations between the AO images and the SD-OCT images were examined. Cone photoreceptors in eight areas in the macula of OMD and healthy control subjects were analyzed and compared.Results: SD-OCT showed a loss of the cone outer-segment tips line outside of the fovea in both eyes of the subject with OMD. The left eye with decreased visual acuity showed a discontinuous photoreceptor inner-segment and outer-segment line and cone outer-segment tips line at the fovea in SD-OCT and loss of cone mosaics as a dark spot in the AO image. In panoramic AO images and cone-density maps, less cone density was observed in a ring-like region outside the fovea than in the peripheral retina. In most of the areas examined, the cone densities were lower in the OMD eyes than in the healthy control eyes.Conclusions: Cone densities in the macula of the OMD patient were greatly decreased. AO images were found to be useful to evaluate morphologic changes in cone photoreceptors in patients with OMD.Keywords: occult macular dystrophy, adaptive optics, cone photoreceptor, cone analysis, optical coherence tomography

Effect of small-scale ionospheric variability on GNSS radio occultation data quality

Science.gov (United States)

Verkhoglyadova, O. P.; Mannucci, A. J.; Ao, C. O.; Iijima, B. A.; Kursinski, E. R.

2015-09-01

Global Navigation Satellite Systems (GNSS) radio occultation (RO) measurements are sensitive to thin ionization layers and small-scale ionosphere structures. To evaluate error bounds and possible biases in atmospheric retrievals, we characterized ionospheric irregularities encountered in the affected profiles by analyzing the L1 signal-to-noise ratio (SNR) variability at E layer altitudes (from 90 km to 130 km). New metrics to analyze statistical effects of small-scale ionospheric irregularities on refractivity retrievals are proposed. We analyzed refractivity (N) retrievals with Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) ROs in 2011. Using refractivity from European Centre for Medium-Range Weather Forecasts (ECMWF) analysis (NECMWF) as the reference data set, we studied statistical properties of the fractional refractivity bias (ΔN) defined by the difference (NECMWF - N)/NECMWF and averaged in the altitude range from 20 to 25 km for each individual profile. We found that (1) persistently larger variability of the L1 SNR as measured by the interquartile range (IQR) existed when the occultation tangent point was in the 90 km to 110 km altitude range than at higher E layer altitudes; (2) the upper limits on the fractional refractivity bias for COSMIC ROs are 0.06% (for daytime local time), 0.1% (for nighttime local time), and ~0.01% (for all local times); (3) distributions of ΔN are non-Gaussian (leptokurtic); (4) latitudinal distributions of small and large ΔN for different levels of ionospheric variability show large tails (NECMWF > N) occurring around the Himalaya and the Andes regions, which are possibly due to biases in ECMWF analysis. We conclude that the refractivity bias due to small-scale irregularities is small below 25 km altitude and can be neglected.

Flow and Transport in Tight and Shale Formations: A Review

KAUST Repository

Salama, Amgad

2017-09-18

A review on the recent advances of the flow and transport phenomena in tight and shale formations is presented in this work. Exploration of oil and gas in resources that were once considered inaccessible opened the door to highlight interesting phenomena that require attention and understanding. The length scales associated with transport phenomena in tight and shale formations are rich. From nanoscale phenomena to field-scale applications, a unified frame that is able to encounter the varieties of phenomena associated with each scale may not be possible. Each scale has its own tools and limitations that may not, probably, be suitable at other scales. Multiscale algorithms that effectively couple simulations among various scales of porous media are therefore important. In this article, a review of the different length scales and the tools associated with each scale is introduced. Highlights on the different phenomena pertinent to each scale are summarized. Furthermore, the governing equations describing flow and transport phenomena at different scales are investigated. In addition, methods to solve these equations using numerical techniques are introduced. Cross-scale analysis and derivation of linear and nonlinear Darcy\\'s scale laws from pore-scale governing equations are described. Phenomena occurring at molecular scales and their thermodynamics are discussed. Flow slippage at the nanosize pores and its upscaling to Darcy\\'s scale are highlighted. Pore network models are discussed as a viable tool to estimate macroscopic parameters that are otherwise difficult to measure. Then, the environmental aspects associated with the different technologies used in stimulating the gas stored in tight and shale formations are briefly discussed.

Flow and Transport in Tight and Shale Formations: A Review

KAUST Repository

Salama, Amgad; El-Amin, Mohamed; Kumar, Kundan; Sun, Shuyu

2017-01-01

A review on the recent advances of the flow and transport phenomena in tight and shale formations is presented in this work. Exploration of oil and gas in resources that were once considered inaccessible opened the door to highlight interesting phenomena that require attention and understanding. The length scales associated with transport phenomena in tight and shale formations are rich. From nanoscale phenomena to field-scale applications, a unified frame that is able to encounter the varieties of phenomena associated with each scale may not be possible. Each scale has its own tools and limitations that may not, probably, be suitable at other scales. Multiscale algorithms that effectively couple simulations among various scales of porous media are therefore important. In this article, a review of the different length scales and the tools associated with each scale is introduced. Highlights on the different phenomena pertinent to each scale are summarized. Furthermore, the governing equations describing flow and transport phenomena at different scales are investigated. In addition, methods to solve these equations using numerical techniques are introduced. Cross-scale analysis and derivation of linear and nonlinear Darcy's scale laws from pore-scale governing equations are described. Phenomena occurring at molecular scales and their thermodynamics are discussed. Flow slippage at the nanosize pores and its upscaling to Darcy's scale are highlighted. Pore network models are discussed as a viable tool to estimate macroscopic parameters that are otherwise difficult to measure. Then, the environmental aspects associated with the different technologies used in stimulating the gas stored in tight and shale formations are briefly discussed.

Analysis of Seven NEPTUN-III (Tight-Lattice) Bottom-Flooding Experiments with RELAP5/MOD3.3/BETA

International Nuclear Information System (INIS)

Analytis, G.Th.

2004-01-01

Seven tight-lattice NEPTUN-III bottom-flooding experiments are analyzed by using the frozen version of RELAP5, RELAP5/MOD3.3/BETA. This work is part of the Paul Scherrer Institute (PSI) contribution to the High Performance Light Water Reactor (HPLWR) European Union project and aims at assessing the capabilities of the code to model the reflooding phenomena in a tight hexagonal lattice (which was one of the core geometries considered at the time for an HPLWR) following a hypothetical loss-of-coolant accident scenario. Even though the latest version of the code has as a default the new PSI reflood model developed by the author, which was tested and assessed against reflooding data obtained at standard light water reactor lattices, this work shows that for tight lattices, the code underpredicts the peak clad temperatures measured during a series of reflooding experiments performed at the NEPTUN-III tight-lattice heater rod bundle facility. The reasons for these differences are discussed, and the (possible) changes needed in the framework of RELAP5/MOD3.3 for improving the modeling of reflooding in tight lattices are investigated

Tight Temporal Bounds for Dataflow Applications Mapped onto Shared Resources

NARCIS (Netherlands)

Alizadeh Ara, H.; Geilen, M.; Basten, T.; Behrouzian, A.R.B.; Hendriks, M.; Goswami, D.

2016-01-01

We present an analysis method that provides tight temporal bounds for applications modeled by Synchronous Dataflow Graphs and mapped to shared resources. We consider the resource sharing effects on the temporal behaviour of the application by embedding worst case resource availability curves in the

Infectivity of blood products from donors with occult hepatitis B virus infection

DEFF Research Database (Denmark)

Allain, Jean-Pierre; Mihaljevic, Ivanka; Gonzalez-Fraile, Maria Isabel

2013-01-01

BACKGROUND: Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors. STUDY DESIGN AND METHODS: Recipients of previous donations from OBI donors were investigated...... blood cells [RBCs], p Donor and recipient strains sequence homology of at least 99% confirmed transfusion-transmitted infection in 10 cases and excluded it in one case. CONCLUSION: Blood...... through lookback (systematic retrieval of recipients) or traceback (triggered by clinical cases). Serologic and genomic studies were undertaken on consenting donors and recipients. Multiple variables potentially affecting infectivity were examined. RESULTS: A total of 45 of 105 (42.9%) donor...

Infective endocarditis detected by 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography in a patient with occult infection

Directory of Open Access Journals (Sweden)

Chia-Lu Yeh

2011-11-01

Full Text Available Integrated 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG PET/CT has been clinically used to detect infectious lesions. We present a case with pyrexia and bacteremia of unknown origin. Whole body FDG PET/CT was arranged to look for an occult source of infection and it revealed a focal lesion with increased FDG uptake in the mitral valve area. Under suspicion of infective endocarditis, transthoracic echocardiography was repeated and then the presence of linear vegetation over the calcified mitral annulus was confirmed. Ultimately, definite infective endocarditis was diagnosed according to the Duke criteria. The patient recovered after the antibiotic therapy. In our case, FDG PET/CT can help to localize the exact site of occult infection, thereby guiding additional testing and facilitating timely definitive diagnosis and therapy.

Neurocutaneous melanocytosis, hemimegalencephaly and large ovarian cyst in a newborn.

Science.gov (United States)

Derinkuyu, Betul E; Boyunaga, Oznur; Unal, Sezin; Ucar, Murat; Ergenekon, Ebru

2015-07-01

We report a case of a newborn girl with neurocutaneous melanocytosis, hemimegalencephaly and a large ovarian cyst. She also had melanocyte deposition in the filum terminale. The ultrasound and the magnetic resonance imaging findings are discussed.

Radio Occultation Experiments with Venus Express and Mars Express using the Planetary Radio Interferometry and Doppler Experiment (PRIDE) Technique

Science.gov (United States)

Bocanegra Bahamon, T.; Gurvits, L.; Molera Calves, G.; Cimo, G.; Duev, D.; Pogrebenko, S.; Dirkx, D.; Rosenblatt, P.

2017-12-01

The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a technique that can be used to enhance multiple radio science experiments of planetary missions. By 'eavesdropping' on the spacecraft signal using radio telescopes from different VLBI networks around the world, the PRIDE technique provides precise open-loop Doppler and VLBI observables to able to reconstruct the spacecraft's orbit. The application of this technique for atmospheric studies has been assessed by observing ESA's Venus Express (VEX) and Mars Express (MEX) during multiple Venus and Mars occultation events between 2012 and 2014. From these observing sessions density, temperature and pressure profiles of Venus and Mars neutral atmosphere and ionosphere have been retrieved. We present an error propagation analysis where the uncertainties of the atmospheric properties measured with this technique have been derived. These activities serve as demonstration of the applicability of the PRIDE technique for radio occultation studies, and provides a benchmark against the traditional Doppler tracking provided by the NASA's DSN and ESA's Estrack networks for these same purposes, in the framework of the upcoming ESA JUICE mission to the Jovian system.

MANAGING TIGHT BINDING RECEPTORS FOR NEW SPEARATIONS TECHNOLOGIES

Energy Technology Data Exchange (ETDEWEB)

DARYLE H BUSCH RICHARD S GIVENS

2004-12-10

Much of the earth's pollution involves compounds of the metallic elements, including actinides, strontium, cesium, technetium, and RCRA metals. Metal ions bind to molecules called ligands, which are the molecular tools that can manipulate the metal ions under most conditions. This DOE-EMSP sponsored program strives (1) to provide the foundations for using the most powerful ligands in transformational separations technologies and (2) to produce seminal examples of their applications to separations appropriate to the DOE EM mission. These ultra tight-binding ligands can capture metal ions in the most competitive of circumstances (from mineralized sites, lesser ligands, and even extremely dilute solutions), but they react so slowly that they are useless in traditional separations methodologies. Two attacks on this problem are underway. The first accommodates to the challenging molecular lethargy by developing a seminal slow separations methodology termed the soil poultice. The second designs ligands that are only tight-binding while wrapped around the targeted metal ion, but can be put in place by switch-binding and removed by switch-release. We envision a kind of molecular switching process to accelerate the union between metal ion and tight-binding ligand. Molecular switching processes are suggested for overcoming the slow natural equilibration rate with which ultra tight-binding ligands combine with metal ions. Ligands that bind relatively weakly combine with metal ions rapidly, so the trick is to convert a ligand from a weak, rapidly binding species to a powerful, slow releasing ligand--during the binding of the ligand to the metal ion. Such switch-binding ligands must react with themselves, and the reaction must take place under the influence of the metal ion. For example, our generation 1 ligands showed that a well-designed linear ligand with ends that readily combine, forms a cyclic molecule when it wraps around a metal ion. Our generation 2 ligands are

Prognostic implications of occult nodal tumour cells in stage I and II colon cancer: The correlation between micrometastasis and disease recurrence

NARCIS (Netherlands)

Sloothaak, D. A. M.; van der Linden, R. L. A.; van de Velde, C. J. H.; Bemelman, W. A.; Lips, D. J.; van der Linden, J. C.; Doornewaard, H.; Tanis, P. J.; Bosscha, K.; van der Zaag, E. S.; Buskens, C. J.

2017-01-01

Occult nodal tumour cells should be categorised as micrometastasis (MMs) and isolated tumour cells (ITCs). A recent meta-analysis demonstrated that MMs, but not ITCs, are prognostic for disease recurrence in patients with stage I/II colon cancer. The objective of this retrospective multicenter study

An improved method for predicting brittleness of rocks via well logs in tight oil reservoirs

Science.gov (United States)

Wang, Zhenlin; Sun, Ting; Feng, Cheng; Wang, Wei; Han, Chuang

2018-06-01

There can be no industrial oil production in tight oil reservoirs until fracturing is undertaken. Under such conditions, the brittleness of the rocks is a very important factor. However, it has so far been difficult to predict. In this paper, the selected study area is the tight oil reservoirs in Lucaogou formation, Permian, Jimusaer sag, Junggar basin. According to the transformation of dynamic and static rock mechanics parameters and the correction of confining pressure, an improved method is proposed for quantitatively predicting the brittleness of rocks via well logs in tight oil reservoirs. First, 19 typical tight oil core samples are selected in the study area. Their static Young’s modulus, static Poisson’s ratio and petrophysical parameters are measured. In addition, the static brittleness indices of four other tight oil cores are measured under different confining pressure conditions. Second, the dynamic Young’s modulus, Poisson’s ratio and brittleness index are calculated using the compressional and shear wave velocity. With combination of the measured and calculated results, the transformation model of dynamic and static brittleness index is built based on the influence of porosity and clay content. The comparison of the predicted brittleness indices and measured results shows that the model has high accuracy. Third, on the basis of the experimental data under different confining pressure conditions, the amplifying factor of brittleness index is proposed to correct for the influence of confining pressure on the brittleness index. Finally, the above improved models are applied to formation evaluation via well logs. Compared with the results before correction, the results of the improved models agree better with the experimental data, which indicates that the improved models have better application effects. The brittleness index prediction method of tight oil reservoirs is improved in this research. It is of great importance in the optimization of

Patient experience of CT colonography and colonoscopy after fecal occult blood test in a national screening programme

OpenAIRE

Plumb, Andrew A.; Ghanouni, Alex; Rees, Colin J.; Hewitson, Paul; Nickerson, Claire; Wright, Suzanne; Taylor, Stuart A.; Halligan, Steve; von Wagner, Christian

2016-01-01

Objective To investigate patient experience of CT colonography (CTC) and colonoscopy in a national screening programme. Methods Retrospective analysis of patient experience postal questionnaires. We included screenees from a fecal occult blood test (FOBt) based screening programme, where CTC was performed when colonoscopy was incomplete or deemed unsuitable. We analyzed questionnaire responses concerning communication of test risks, test-related discomfort and post-test pain, as well as compl...

Patient experience of CT colonography and colonoscopy after fecal occult blood test in a national screening programme

OpenAIRE

Plumb, A. A.; Ghanouni, A.; Rees, C. J.; Hewitson, P.; Nickerson, C.; Wright, S.; Taylor, S. A.; Halligan, S.; von Wagner, C.

2017-01-01

OBJECTIVE: To investigate patient experience of CT colonography (CTC) and colonoscopy in a national screening programme. METHODS: Retrospective analysis of patient experience postal questionnaires. We included screenees from a fecal occult blood test (FOBt) based screening programme, where CTC was performed when colonoscopy was incomplete or deemed unsuitable. We analyzed questionnaire responses concerning communication of test risks, test-related discomfort and post-test pain, as well as com...

Subchannel analysis of 37-rod tight-lattice bundle experiments for reduced-moderation water reactor

International Nuclear Information System (INIS)

Nakatsuka, Toru; Tamai, Hidesada; Akimoto, Hajime

2005-01-01

R and D project to investigate thermal-hydraulic performance of tight-lattice fuel bundles for Reduced-Moderation Water Reactor (RMWR) started at Japan Atomic Energy Research Institute (JAERI) in collaboration with utilities, reactor vendors and universities from 2002. The RMWR realizes a high conversion ratio larger than 0.1 for sustainable energy supply through plutonium multiple recycling based on the well-experienced LWR technologies. The reactor core comprises tight-lattice fuel assemblies with gap clearance of around 1.0 mm to reduce the water volume ratio to achieve the high conversion ratio. A problem of utmost importance from a thermal-hydraulic point of view is the coolability of the tight-lattice assembly with such a small gap width. JAERI has been carrying out experimental study to investigate the system parameter effects on the thermal-hydraulic performance and to confirm the feasibility of the core. In the present study, the subchannel analysis code NASCA was applied to 37-rod tight-lattice bundle experiments. The NASCA can give good predictions of critical power for the gap width of 1.3 mm while the prediction accuracy decreases for the gap width of 1.0 mm. To improve the prediction accuracy, the code will be modified to take the effect of film thickness distribution around fuel rods on boiling transition. (author)

Air tightness of new houses in the U.S.: A preliminary report; TOPICAL

International Nuclear Information System (INIS)

Sherman, Max H.; Matson, Nance E.

2002-01-01

Most dwellings in the United States are ventilated primarily through leaks in the building shell (i.e., infiltration) rather than by whole-house mechanical ventilation systems. Consequently, quantification of envelope air-tightness is critical to determining how much energy is being lost through infiltration and how much infiltration is contributing toward ventilation requirements. Envelope air tightness and air leakage can be determined from fan pressurization measurements with a blower door. Tens of thousands of unique fan pressurization measurements have been made of U.S. dwellings over the past decades. LBNL has collected the available data on residential infiltration into its Residential Diagnostics Database, with support from the U.S. Department of Energy. This report documents the envelope air leakage section of the LBNL database, with particular emphasis on new construction. The work reported here is an update of similar efforts carried out a decade ago, which used available data largely focused on the housing stock, rather than on new construction. The current effort emphasizes shell tightness measurements made on houses soon after they are built. These newer data come from over two dozen datasets, including over 73,000 measurements spread throughout a majority of the U.S. Roughly one-third of the measurements are for houses identified as energy-efficient through participation in a government or utility program. As a result, the characteristics reported here provide a quantitative estimate of the impact that energy-efficiency programs have on envelope tightness in the US, as well as on trends in construction

Neurocutaneous melanocytosis, hemimegalencephaly and large ovarian cyst in a newborn

International Nuclear Information System (INIS)

Derinkuyu, Betul E.; Boyunaga, Oznur; Unal, Sezin; Ergenekon, Ebru; Ucar, Murat

2015-01-01

We report a case of a newborn girl with neurocutaneous melanocytosis, hemimegalencephaly and a large ovarian cyst. She also had melanocyte deposition in the filum terminale. The ultrasound and the magnetic resonance imaging findings are discussed. (orig.)

Neurocutaneous melanocytosis, hemimegalencephaly and large ovarian cyst in a newborn

Energy Technology Data Exchange (ETDEWEB)

Derinkuyu, Betul E.; Boyunaga, Oznur [Gazi University School of Medicine, Department of Radiology, Division of Pediatric Radiology, Besevler, Ankara (Turkey); Unal, Sezin; Ergenekon, Ebru [Gazi University School of Medicine, Department of Pediatrics, Division of Neonatology, Besevler, Ankara (Turkey); Ucar, Murat [Gazi University School of Medicine, Department of Radiology, Besevler, Ankara (Turkey)

2015-08-15

We report a case of a newborn girl with neurocutaneous melanocytosis, hemimegalencephaly and a large ovarian cyst. She also had melanocyte deposition in the filum terminale. The ultrasound and the magnetic resonance imaging findings are discussed. (orig.)

Conditioned medium from LS 174T goblet cells treated with oxyresveratrol strengthens tight junctions in Caco-2 cells.

Science.gov (United States)

Hwang, Dahyun; Jo, HyunA; Hwang, Seonwook; Kim, Jeong-Keun; Kim, In-Ho; Lim, Young-Hee

2017-01-01

Strengthening of intestinal tight junctions provides an effective barrier from the external environment. Goblet cell-derived trefoil factor 3 (TFF3) increases transepithelial resistance by upregulating the expression of tight junction proteins. Oxyresveratrol (OXY) is a hydroxyl-substituted stilbene found in the roots, leaves, stems, and fruit of many plants and known to have various biological activities. In this study, we investigated the strengthening effect of OXY on intestinal tight junctions through stimulation of TFF production in goblet cells. We prepared conditioned medium from LS 174T goblet cells treated with OXY (GCO-CM) and investigated the effect of GCO-CM on strengthening tight junctions of Caco-2 cells. The mRNA and protein expression levels of major tight junction components (claudin-1, occludin, and ZO-1) were measured by quantitative real-time PCR and western blotting, respectively. Transepithelial electric resistance (TEER) was measured using an ohm/V meter. Monolayer permeability was evaluated by paracellular transport of fluorescein isothiocyanate-dextran. OXY showed a strong antioxidant activity. It significantly increased the expression level of TFF3 in LS 174T goblet cells. GCO-CM prepared by treatment with 2.5, 5, and 10μg/ml OXY did not show cytotoxicity in Caco-2 cells. GCO-CM increased the mRNA and protein expression levels of claudin-1, occludin, and ZO-1. It also significantly increased tight junction integrity and reduced permeability in a dose-dependent manner. OXY stimulates the expression of TFF3 in goblet cells, which might increase the integrity of the intestinal tight junction barrier. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The role of computed tomography in the diagnosis and management of clinically occult post-traumatic small bowel perforation

International Nuclear Information System (INIS)

Ahmed, I.; Ahmed, N.; Bell, D.J.; Hughes, D.V.; Evans, G.H.; Howlett, D.C.

2009-01-01

Purpose: To evaluate the use of computed tomography [CT] in the diagnosis of occult post-traumatic small bowel perforation and to discuss the role of CT in the management of this patient group. Method: This review includes three patients who presented with mild abdominal symptoms following minor blunt abdominal trauma. Initial radiographs and laboratory investigations were unremarkable but their symptoms failed to resolve and contrast-enhanced CT was performed for further evaluation. Results: In each case the CT appearances were indicative of localised small bowel perforation, with no evidence of other visceral injury. In two patients pockets of free intraperitoneal air were present closely related to the second part of the duodenum suggesting injury at this site. In the third case, a thickened proximal jejunal loop was demonstrated with free air and fluid in the adjacent mesentery consistent with a focal perforation. These CT findings were subsequently confirmed at laparotomy. Conclusion: CT is an accurate diagnostic tool in the assessment of clinically and radiologically occult traumatic small bowel injury. The use of CT should be considered in patients who have unresolving abdominal symptoms even after apparently insignificant abdominal trauma.

Dynamic statistical optimization of GNSS radio occultation bending angles: advanced algorithm and performance analysis

Science.gov (United States)

Li, Y.; Kirchengast, G.; Scherllin-Pirscher, B.; Norman, R.; Yuan, Y. B.; Fritzer, J.; Schwaerz, M.; Zhang, K.

2015-08-01

We introduce a new dynamic statistical optimization algorithm to initialize ionosphere-corrected bending angles of Global Navigation Satellite System (GNSS)-based radio occultation (RO) measurements. The new algorithm estimates background and observation error covariance matrices with geographically varying uncertainty profiles and realistic global-mean correlation matrices. The error covariance matrices estimated by the new approach are more accurate and realistic than in simplified existing approaches and can therefore be used in statistical optimization to provide optimal bending angle profiles for high-altitude initialization of the subsequent Abel transform retrieval of refractivity. The new algorithm is evaluated against the existing Wegener Center Occultation Processing System version 5.6 (OPSv5.6) algorithm, using simulated data on two test days from January and July 2008 and real observed CHAllenging Minisatellite Payload (CHAMP) and Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) measurements from the complete months of January and July 2008. The following is achieved for the new method's performance compared to OPSv5.6: (1) significant reduction of random errors (standard deviations) of optimized bending angles down to about half of their size or more; (2) reduction of the systematic differences in optimized bending angles for simulated MetOp data; (3) improved retrieval of refractivity and temperature profiles; and (4) realistically estimated global-mean correlation matrices and realistic uncertainty fields for the background and observations. Overall the results indicate high suitability for employing the new dynamic approach in the processing of long-term RO data into a reference climate record, leading to well-characterized and high-quality atmospheric profiles over the entire stratosphere.

Intracellular pH is a tightly controlled signal in yeast

NARCIS (Netherlands)

Orij, R.; Brul, S.; Smits, G.J.

2011-01-01

Background: Nearly all processes in living cells are pH dependent, which is why intracellular pH (pHi) is a tightly regulated physiological parameter in all cellular systems. However, in microbes such as yeast, pHi responds to extracellular conditions such as the availability of nutrients. This

A characterization of tight and dual generalized translation invariant frames

DEFF Research Database (Denmark)

Jakobsen, Mads Sielemann; Lemvig, Jakob

2015-01-01

such systems form tight frames, and when two GTI Bessel systems form dual frames for L2(G). In particular, this offers a unified approach to the theory of discrete and continuous frames and, e.g., yields well known results for discrete and continuous Gabor and wavelet systems....

Impact of tropospheric scintillation in the Ku/K bands on the communications between two LEO satellites in a radio occultation geometry

DEFF Research Database (Denmark)

Martini, Enrica; Freni, A.; Facheris, L.

2006-01-01

A theoretical analysis of the impact of clear-air tropospheric scintillation on a radio occultation link between two low Earth orbit satellites in K- and Ku-bands is presented, with particular reference to differential approaches for the measure of the total content of water vapor. The troposphere...

Tight binding simulation study on zigzag single-walled carbon nanotubes

Science.gov (United States)

Sharma, Deepa; Jaggi, Neena; Gupta, Vishu

2018-01-01

Tight binding simulation studies using the density functional tight binding (DFTB) model have been performed on various zigzag single-walled carbon-nanotubes (SWCNTs) to investigate their electronic properties using DFTB module of the Material Studio Software version 7.0. Various combinations of different eigen-solvers and charge mixing schemes available in the DFTB Module have been tried to chalk out the electronic structure. The analytically deduced values of the bandgap of (9, 0) SWCNT were compared with the experimentally determined value reported in the literature. On comparison, it was found that the tight binding approximations tend to drastically underestimate the bandgap values. However, the combination of Anderson charge mixing method with standard eigensolver when implemented using the smart algorithm was found to produce fairly close results. These optimized model parameters were then used to determine the band structures of various zigzag SWCNTs. (9, 0) Single-walled Nanotube which is extensively being used for sensing NH3, CH4 and NO2 has been picked up as a reference material since its experimental bandgap value has been reported in the literature. It has been found to exhibit a finite energy bandgap in contrast to its expected metallic nature. The study is of utmost significance as it not only probes and validates the simulation route for predicting suitable properties of nanomaterials but also throws light on the comparative efficacy of the different approximation and rationalization quantum mechanical techniques used in simulation studies. Such simulation studies if used intelligently prove to be immensely useful to the material scientists as they not only save time and effort but also pave the way to new experiments by making valuable predictions.

Atmospheric influences on infrared-laser signals used for occultation measurements between Low Earth Orbit satellites

Directory of Open Access Journals (Sweden)

S. Schweitzer

2011-10-01

Full Text Available LEO-LEO infrared-laser occultation (LIO is a new occultation technique between Low Earth Orbit (LEO satellites, which applies signals in the short wave infrared spectral range (SWIR within 2 μm to 2.5 μm. It is part of the LEO-LEO microwave and infrared-laser occultation (LMIO method that enables to retrieve thermodynamic profiles (pressure, temperature, humidity and altitude levels from microwave signals and profiles of greenhouse gases and further variables such as line-of-sight wind speed from simultaneously measured LIO signals. Due to the novelty of the LMIO method, detailed knowledge of atmospheric influences on LIO signals and of their suitability for accurate trace species retrieval did not yet exist. Here we discuss these influences, assessing effects from refraction, trace species absorption, aerosol extinction and Rayleigh scattering in detail, and addressing clouds, turbulence, wind, scattered solar radiation and terrestrial thermal radiation as well. We show that the influence of refractive defocusing, foreign species absorption, aerosols and turbulence is observable, but can be rendered small to negligible by use of the differential transmission principle with a close frequency spacing of LIO absorption and reference signals within 0.5%. The influences of Rayleigh scattering and terrestrial thermal radiation are found negligible. Cloud-scattered solar radiation can be observable under bright-day conditions, but this influence can be made negligible by a close time spacing (within 5 ms of interleaved laser-pulse and background signals. Cloud extinction loss generally blocks SWIR signals, except very thin or sub-visible cirrus clouds, which can be addressed by retrieving a cloud layering profile and exploiting it in the trace species retrieval. Wind can have a small influence on the trace species absorption, which can be made negligible by using a simultaneously retrieved or a moderately accurate background wind speed profile. We

MRI of occult sacral insufficiency fractures following radiotherapy

International Nuclear Information System (INIS)

Mammone, J.F.; Schweitzer, M.E.

1995-01-01

Following radiation therapy, marrow abnormalities noted on magnetic resonance imaging (MRI) are frequent and may mimic metastases. Specific radiotherapy changes are usually easily identifiable; however, traumatic lesions cause more interpretive difficulties. We assessed the incidence and MRI characteristics of insufficiency fractures in this population. During a 5-year span (1987-1991), 546 patients received pelvic radiotherapy for primary malignancies. MRI was performed in 25 of these patients at least 3 months after treatment. The mean dose in this group was 53 Gy. These MRI scans were retrospectively reviewed for the appearance of the sacrum with particular attention to the presence of insufficiency fractures. This was correlated with clinical course and scintigraphic findings. Presumed insufficiency fractures on MRI paralleled the sacral side of the sacroiliac joint, enhanced with Gd-DTPA, were most prominent or initially seen anteriorly, and had ill-defined margins on all imaging sequences. The incidence of occult sacral insufficiency fractures was at least 20%. Insufficiency fractures of the sacrum in the post-radiotherapy patient are a relatively frequent occurrence which can mimic metastases. Consideration of this phenomenon and knowledge of differential features may avoid overdiagnosis of osseous metastases. (orig.)

Assimilation of GNSS radio occultation observations in GRAPES

Science.gov (United States)

Liu, Y.; Xue, J.

2014-07-01

This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction) analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3) satellites, the research status of the RO of FY-3 satellites is also presented.

Diffusion tensor imaging of occult injury of optic radiation following optic neuritis in multiple sclerosis.

Science.gov (United States)

Chen, Jiafeng; Zhu, Lijun; Li, He; Lu, Ziwen; Chen, Xin; Fang, Shaokuan

2016-10-01

Multiple sclerosis (MS) is easily detected by routine magnetic resonance imaging (MRI). However, it is not possible to detect early or occult lesions in MS by routine MRI, and this may explain the inconsistency between the severity of the lesions found by MRI and the degree of clinical disability of patients with MS. The present study included 10 patients with relapsing-remitting MS and 10 healthy volunteers. Each patient underwent routine 3.0 T MRI, diffusion tensor imaging (DTI), and diffusion tensor tractography (DTT). Optic nerve and optic radiation were analyzed by DTI and DTT. The fractional anisotropy (FA), mean diffusivity (MD), λ // , and λ ┴ values were measured. In the 10 patients with MS, 7 optic nerves were affected, and 13 optic nerves were not affected. Cranial MRI showed that optic nerve thickening and hyperintensity occurred in 2 patients with MS. In the directionally encoded color maps, a hypointensive green signal in the optic nerve was observed in 3 patients with MS. The FA values were significantly lower and the MD, λ // , and λ ┴ values were significantly higher in the affected and unaffected optic nerves and optic radiations in patients with MS in comparison with controls (P0.05). Diffusion tensor imaging is sensitive in the detection of occult injury of the optic nerve and optic radiation following optic neuritis. Diffusion tensor imaging may be a useful tool for the early diagnosis, treatment and management of MS.

Hard X-Ray Emission from Partially Occulted Solar Flares: RHESSI Observations in Two Solar Cycles

Energy Technology Data Exchange (ETDEWEB)

Effenberger, Frederic; Costa, Fatima Rubio da; Petrosian, Vahé [Department of Physics and KIPAC, Stanford University, Stanford, CA 94305 (United States); Oka, Mitsuo; Saint-Hilaire, Pascal; Krucker, Säm [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Liu, Wei [Bay Area Environmental Research Institute, 625 2nd Street, Suite 209, Petaluma, CA 94952 (United States); Glesener, Lindsay, E-mail: feffen@stanford.edu, E-mail: frubio@stanford.edu [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

2017-02-01

Flares close to the solar limb, where the footpoints are occulted, can reveal the spectrum and structure of the coronal looptop source in X-rays. We aim at studying the properties of the corresponding energetic electrons near their acceleration site, without footpoint contamination. To this end, a statistical study of partially occulted flares observed with Reuven Ramaty High-Energy Solar Spectroscopic Imager is presented here, covering a large part of solar cycles 23 and 24. We perform detailed spectra, imaging, and light curve analyses for 116 flares and include contextual observations from SDO and STEREO when available, providing further insights into flare emission that were previously not accessible. We find that most spectra are fitted well with a thermal component plus a broken power-law, non-thermal component. A thin-target kappa distribution model gives satisfactory fits after the addition of a thermal component. X-ray imaging reveals small spatial separation between the thermal and non-thermal components, except for a few flares with a richer coronal source structure. A comprehensive light curve analysis shows a very good correlation between the derivative of the soft X-ray flux (from GOES ) and the hard X-rays for a substantial number of flares, indicative of the Neupert effect. The results confirm that non-thermal particles are accelerated in the corona and estimated timescales support the validity of a thin-target scenario with similar magnitudes of thermal and non-thermal energy fluxes.

Vaginal prolapse repair with or without a midurethral sling in women with genital prolapse and occult stress urinary incontinence : a randomized trial

NARCIS (Netherlands)

van der Ploeg, J Marinus; Rengerink, Katrien Oude; van der Steen, Annemarie; van Leeuwen, Jules H Schagen; van der Vaart, C Huub; Roovers, Jan-Paul W R

INTRODUCTION AND HYPOTHESIS: We compared pelvic organ prolapse (POP) repair with and without midurethral sling (MUS) in women with occult stress urinary incontinence (SUI). METHODS: This was a randomized trial conducted by a consortium of 13 teaching hospitals assessing a parallel cohort of

Tratamento artroscópico da luxação acromio-clavicular pelo método "tight rope" (arthrex® Arthroscopic treatment of acromioclavicular joint dislocation by tight rope technique (arthrex®

Directory of Open Access Journals (Sweden)

Luis Alfredo Gómez Vieira

2009-02-01

Full Text Available OBJETIVO: Apresentar a técnica cirúrgica artroscópica pelo método "Tight Rope" e a avaliação dos resultados com esta técnica no tratamento da luxação acrômio-clavicular aguda. MÉTODOS: entre agosto de 2006 e maio de 2007, 10 ombros de 10 pacientes com luxação acrômio-clavicular aguda foram submetidos a tratamento artroscópcio pela técnica Tight Rope-Arthrex®. O seguimento mínimo foi de 12 meses, com média de 15 meses. A idade variou de 26 e 42 anos com média de 34 anos. Todos os pacientes eram do sexo masculino. Todos os pacientes foram atendidos na fase aguda da lesão sendo avaliados por radiologia simples (série trauma. Os pacientes foram acompanhados semanalmente no primeiro mês e a cada três meses após o procedimento artroscópico. A avaliação clínica foi feita por meio dos critérios da University of Califórnia at Los Angeles (UCLA. RESULTADOS: Todos os pacientes operados agudamente encontravam-se satisfeitos com os resultados do tratamento cirúrgico artroscópico com uma média de 32,5 pontos na escala de avaliação da UCLA. CONCLUSÃO: O tratamento artroscópico da luxação acrômio-clavicular aguda pelo método "Tight Rope" é uma técnica cirúrgica minimamente invasiva que mostrou-se eficiente para o tratamento destas lesões.OBJECTIVE: Presenting the arthroscopic treatment by Tight Rope - Arthrex® system for acute acromioclavicular dislocation and to evaluate results obtained with this procedure. METHODS: Between August 2006 and May 2007, 10 shoulders of 10 patients with acute acromioclavicular dislocation were submitted to arthroscopic repair using the Tight Rope - Arthrex® system. Minimum follow-up was 12 months, with a mean of 15 months. Age ranged from 26 to 42, mean 34 years. All patients were male. Radiology evaluation was made by trauma series x-ray. The patients were assisted in the first month weekly and after three months after the procedure. Clinical evaluation was based on the University

Wavelength dependence of the effects of turbulence on average refraction angles in occultations by planetary atmospheres

International Nuclear Information System (INIS)

Haugstad, B.S.; Eshleman, V.R.

1979-01-01

Two recent adjacently published papers on the average effects of turbulence in radio and optical occultation studies of planetary atmospheres appear to disagree on the question of wavelength dependence. It is demonstrated here that in deriving a necessary condition for the applicability of their method. Hubbard and Jokipii neglect a factor which is proportional to the square of the ratio of the atmospheric or local Fresnel zone radius and the inner scale of turbulence. They also fail to establish sufficient conditions, thereby omitting as a further factor the square of the ratio of atmospheric scale height and the local Fresnel zone radius. The total descrepancy, which numerically is typically within several orders of magnitude of 10 11 for radio and 10 7 for optical occultations, means that their results correspond to geometrical optics and not to wave optics as claimed. Thus their results are inherently inapplicable in a discussion of the wavelength dependence of any parameter, such as the bias in the average refraction angle treated by Eshleman and Haugstad. We note that for power spectra characterized by the (--p) exponent of the turbulence wavenumber, the average turbulence-induced bias in refraction angles depends on the radiation wavelength as lambda/sup( p/--4)/2, or as lambda/sup en-dash1/6/ for Kolmogorov turbulence. Other features of the Hubbard-Jokipii analysis are also discussed

A unique airborne observation. [Martian atmospheric temperature and abundances from occultation of Epsilon Geminorum

Science.gov (United States)

Elliot, J. L.; Dunham, E.; Church, C.

1976-01-01

The occultation of 3rd magnitude Epsilon Geminorum by Mars was observed using a 36-inch telescope equipped with a photoelectric photometer at the bent Cassegrain focus, carried aboard the Kuiper Airborne Observatory at altitudes up to 45,000 feet. Scintillation from the earth's atmosphere was greatly reduced in comparison with ground observations. The observations clearly show the central flash, caused by the symmetrical refraction of light by the atmosphere of Mars. The data are being analyzed to obtain temperature profiles and to assess the relative abundance of argon and carbon dioxide in the atmosphere of the planet.

Invasive tightly coupled processor arrays

CERN Document Server

LARI, VAHID

2016-01-01

This book introduces new massively parallel computer (MPSoC) architectures called invasive tightly coupled processor arrays. It proposes strategies, architecture designs, and programming interfaces for invasive TCPAs that allow invading and subsequently executing loop programs with strict requirements or guarantees of non-functional execution qualities such as performance, power consumption, and reliability. For the first time, such a configurable processor array architecture consisting of locally interconnected VLIW processing elements can be claimed by programs, either in full or in part, using the principle of invasive computing. Invasive TCPAs provide unprecedented energy efficiency for the parallel execution of nested loop programs by avoiding any global memory access such as GPUs and may even support loops with complex dependencies such as loop-carried dependencies that are not amenable to parallel execution on GPUs. For this purpose, the book proposes different invasion strategies for claiming a desire...

Enhanced bilateral somatostatin receptor expression in mediastinal lymph nodes (''chimney sign'') in occult metastatic medullary thyroid cancer: a typical site of tumour manifestation?

International Nuclear Information System (INIS)

Behr, T.M.; Gratz, S.; Markus, P.M.; Dunn, R.M.; Huefner, M.; Becker, H.; Becker, W.

1997-01-01

In medullary thyroid cancer (MTC), post-surgically elevated plasma calcitonin and/or carcinoembryonic antigen levels frequently indicate persisting metastatic disease, although conventional diagnostic procedures fail to localize the responsible lesions (occult disease). Somatostatin analogues have been used successfully in disease localization, but recently concerns have been raised that increased thoracic uptake of indium-111 pentetreotide in patients with previous external beam irradiation may represent a false-positive finding, caused by post-irradiation pulmonary fibrosis. We recently examined seven patients with metastatic MTC by somatostatin receptor scintigraphy (six with occult and one with established disease). In four patients, all of whom had stable or slowly rising tumour marker levels over several years, a chimney-like bilateral mediastinal uptake of indium-111 pentetreotide was found. In two patients with persisting hypercalcitonaemia immediately after primary surgery, supraclavicular lymph node metastases were identified as the responsible lesions. None of these seven patients had prior external beam radiation therapy. In two cases, histological confirmation was obtained. In one patient, disease progression could be shown during follow-up. These data suggest that bilateral mediastinal lymph node involvement is a typical site of disease in slowly progressing occult metastatic MTC; the ''chimney sign'' may represent a typical finding with somatostatin analogues in such cases. Therefore, we believe that even in the case of prior external beam irradiation, mediastinal uptake of octreotide might represent metastatic MTC rather than radiation fibrosis. (orig.). With 2 figs., 1 tab

Tightly sealed facility of excellent in durability

International Nuclear Information System (INIS)

Shirano, Kenji; Chatani, Michio; Ebe, Shinji; Shimizu, Masatoshi; Seguchi, Tadao; Fukushima, Susumu; Hirata, Masaru; Shiosawa, Ken-ichi.

1992-01-01

It is found that a cross linked methacryl resin using an appropriate amount of a cross linking monomer also has a useful characteristic of an excellent chemical resistance and excellent γ-ray resistance. Then in the present invention, a cross linked methacryl resin molding product comprising 60 to 98 % by weight of methyl methacrylate units and 2 to 40 % by weight of cross linking monomer units is used as a material for transparent partition walls. A tightly sealed facility having the transparent partition wall materials of excellent radiation resistance in addition to acid resistance can be attained. (T.M.)

Ultra-High Resolution Orbit Determination of (486958) 2014 MU69: Predicting an Occultation with 1% of an Orbit

Science.gov (United States)

Porter, Simon Bernard; Buie, Marc W.; Spencer, John R.; Folkner, William; Parker, Alex; Zangari, Amanda Marie; Verbiscer, Anne J.; Benecchi, Susan; Stern, S. Alan; Terrell, Dirk; Soto, Alejandro; Tamblyn, Peter; Wasserman, Lawrence H.; Young, Eliot F.; New Horizons MU69 Occultation Team

2017-10-01

In November 2015, the NASA New Horizons spacecraft burned its thrusters to intercept the cold classical Kuiper Belt Object (486958) 2014 MU69. Then, on July 17, 2017, five small telescopes in Chubut Province, Argentina recorded a solid body occultation of MU69. Both these events required an orbital solution of unprecedented accuracy, as will the January 1, 2019 flyby of MU69 by New Horizons. This was especially difficult because there were no precoveries of MU69 prior to July 2014, it is in an extremely crowded field near the galactic core, and it is faint enough to only be reliably detected by Hubble Space Telescope’s Wide Field Camera 3 (WFC3). To accomplish this, we performed an extremely detailed analysis of 237 WFC3 images, down to the subpixel distortion level, in order to produce individual probability distribution functions (PDFs) for the position of MU69 in each WFC3 image. We registered each WFC3 image against a pre-release version of the Gaia DR2 catalog, which produced even smaller residuals than the now-released DR1. We then combined these WFC3+Gaia PDFs with a high-precision few-body numerical integrator and a Monte Carlo Markov Chain (MCMC) sampler to produce a state vector PDF for MU69 at defined epoch. Propagating those state vectors from the epoch produces an instantaneous positional cloud for MU69 at any given time. This positional cloud was then directly translated into a shadow path uncertainty cloud in order to plan the MU69 occultation campaign. We will describe this process of fully propagating errors from WFC3 images to telescope sites on the ground, and also describe refinements for future guiding of New Horizons to its encounter with MU69. We thank NASA, Hubble, Gaia, CONAE, the city of Comodoro Rivadavia, and the government of Argentina for their assistance and support of the MU69 occultation campaign.

Radio occultation studies of the Venus atmosphere with the Magellan spacecraft. 2: Results from the October 1991 experiments

Science.gov (United States)

Jenkins, Jon M.; Steffes, Paul G.; Hinson, David P.; Twicken, Joseph D.; Tyler, G. Leonard

1994-01-01

On October 5 and 6, 1991, three dual-frequency ingress radio occultation experiments were conducted at Venus during consecutive orbits of the Magellan spacecraft. The radio signals probed a region of the atmosphere near 65 deg N, with a solar zenith angle of 108 deg, reaching below 35 km at 3.6 cm, and below 34 km at 13 cm (above a mean radius of 6052 km). The high effective isotropic radiated power (EIRP) of the Magellan spacecraft and highly successful attitude maneuvers allowed these signals to probe deeper than any previous radio occultation experiment and also resulted in the most accurate thermal and sulfuric acid vapor abundance profiles ever obtained at Venus through radio occultation techniques. The performance of the spacecraft and the experiment design are discussed in an accompanying paper. Average electron density profiles retrieved from the data possess peaks between 2600 and 6000/cu cm, well below typical values of 10,000/cu cm retrieved in 1979 by Pioneer Venus at similar solar zenith angles. Other basic results include vertical profiles of temperature, pressure, and density in the neutral atmosphere, 13- and 3.6-cm absorpttivity, and H2SO4 (g) abundance below the main cloud layer. H2SO4 (g) becomes significant below 50 km, reaching peaks between 18 and 24 ppm near 39 km before dropping precipitously below 38 km. These sharp decreases confirm the thermal decomposition of sulfuric acid vapor below 39 km. Since the Venus atmosphere rotated approximately 10 deg between experiments, the data contain information about the horizontal variability of the atmosphere. All derived profiles exhibit significant variations from orbit to orbit, indicating the presence of dynamical processes between 33 and 200 km. In particular, the orbit-to-orbit variations in temperature and in H2SO4 (g) abundance appear to be correlated, suggesting that a common mechanism may be responsible for the observed spatial variations.

Petri Net-Based Model of Helicobacter pylori Mediated Disruption of Tight Junction Proteins in Stomach Lining during Gastric Carcinoma

Directory of Open Access Journals (Sweden)

Anam Naz

2017-09-01

Full Text Available Tight junctions help prevent the passage of digestive enzymes and microorganisms through the space between adjacent epithelial cells lining. However, Helicobacter pylori encoded virulence factors negatively regulate these tight junctions and contribute to dysfunction of gastric mucosa. Here, we have predicted the regulation of important tight junction proteins, such as Zonula occludens-1, Claudin-2 and Connexin32 in the presence of pathogenic proteins. Molecular events such as post translational modifications and crosstalk between phosphorylation, O-glycosylation, palmitoylation and methylation are explored which may compromise the integrity of these tight junction proteins. Furthermore, the signaling pathways disrupted by dysregulated kinases, proteins and post-translational modifications are reviewed to design an abstracted computational model showing the situation-dependent dynamic behaviors of these biological processes and entities. A qualitative hybrid Petri Net model is therefore constructed showing the altered host pathways in the presence of virulence factor cytotoxin-associated gene A, leading to the disruption of tight junction proteins. The model is qualitative logic-based, which does not depend on any kinetic parameter and quantitative data and depends on knowledge derived from experiments. The designed model provides insights into the tight junction disruption and disease progression. Model is then verified by the available experimental data, nevertheless formal in vitro experimentation is a promising way to ensure its validation. The major findings propose that H. pylori activated kinases are responsible to trigger specific post translational modifications within tight junction proteins, at specific sites. These modifications may favor alterations in gastric barrier and provide a route to bacterial invasion into host cells.

Effects of turbulence on average refraction angles in occultations by planetary atmospheres

Science.gov (United States)

Eshleman, V. R.; Haugstad, B. S.

1978-01-01

Four separable effects of atmospheric turbulence on average refraction angles in occultation experiments are derived from a simplified analysis, and related to more general formulations by B. S. Haugstad. The major contributors are shown to be due to gradients in height of the strength of the turbulence, and the sense of the resulting changes in refraction angles is explained in terms of Fermat's principle. Because the results of analyses of such gradient effects by W. B. Hubbard and J. R. Jokipii are expressed in other ways, a special effort is made to compare all of the predictions on a common basis. We conclude that there are fundamental differences, and use arguments based on energy conservation and Fermat's principle to help characterize the discrepancies.

Design and construction of a 76m long-travel laser enclosure for a space occulter testbed

Science.gov (United States)

Galvin, Michael; Kim, Yunjong; Kasdin, N. Jeremy; Sirbu, Dan; Vanderbei, Robert; Echeverri, Dan; Sagolla, Giuseppe; Rousing, Andreas; Balasubramanian, Kunjithapatham; Ryan, Daniel; Shaklan, Stuart; Lisman, Doug

2016-07-01

Princeton University is upgrading our space occulter testbed. In particular, we are lengthening it to 76m to achieve flightlike Fresnel numbers. This much longer testbed required an all-new enclosure design. In this design, we prioritized modularity and the use of commercial off-the-shelf (COTS) and semi-COTS components. Several of the technical challenges encountered included an unexpected slow beam drift and black paint selection. Herein we describe the design and construction of this long-travel laser enclosure.

Impact of GPS Radio Occultation Refractivity Soundings on a Simulation of Typhoon Bilis (2006 upon Landfall

Directory of Open Access Journals (Sweden)

Mien-Tze Kueh

2009-01-01

Full Text Available Typhoon Bilis which struck Taiwan in July 2006 was chosen to assess the potential impact of GPS radio occultation (RO refractivity soundings on numerical simulation using the WRF model. We found that this case elucidates the impact of the limited GPS RO soundings on typhoon prediction due to their favorable locations. In addition, on top of available precipitable water (PW and near-surface wind speed from SSM/I data, we have also explored their combined impacts on model prediction.

Evaluation of tight-pitch PWR cores

International Nuclear Information System (INIS)

Correa, F.; Driscoll, M.J.; Lanning, D.D.

1979-08-01

The impact of tight pinch cores on the consumption of natural uranium ore has been evaluated for two systems of coupled PWR's namely one particular type of thorium system - 235 U/UO 2 : Pu/ThO 2 : 233 U/ThO 2 - and the conventional recycle-mode uranium system - 235 U/UO 2 : Pu/UO 2 . The basic parameter varied was the fuel-to-moderator volume ratio (F/M) of the (uniform) lattice for the last core in each sequence. Although methods and data verification in the range of present interest, 0.5 (current lattices) 1.0, the EPRI-LEOPARD and LASER programs used for the thorium and uranium calculations, respectively, were successfully benchmarked against several of the more pertinent experiments

Behavior of tight-junction, adherens-junction and cell polarity proteins during HNF-4α-induced epithelial polarization

International Nuclear Information System (INIS)

Satohisa, Seiro; Chiba, Hideki; Osanai, Makoto; Ohno, Shigeo; Kojima, Takashi; Saito, Tsuyoshi; Sawada, Norimasa

2005-01-01

We previously reported that expression of tight-junction molecules occludin, claudin-6 and claudin-7, as well as establishment of epithelial polarity, was triggered in mouse F9 cells expressing hepatocyte nuclear factor (HNF)-4α [H. Chiba, T. Gotoh, T. Kojima, S. Satohisa, K. Kikuchi, M. Osanai, N. Sawada. Hepatocyte nuclear factor (HNF)-4α triggers formation of functional tight junctions and establishment of polarized epithelial morphology in F9 embryonal carcinoma cells, Exp. Cell Res. 286 (2003) 288-297]. Using these cells, we examined in the present study behavior of tight-junction, adherens-junction and cell polarity proteins and elucidated the molecular mechanism behind HNF-4α-initiated junction formation and epithelial polarization. We herein show that not only ZO-1 and ZO-2, but also ZO-3, junctional adhesion molecule (JAM)-B, JAM-C and cell polarity proteins PAR-3, PAR-6 and atypical protein kinase C (aPKC) accumulate at primordial adherens junctions in undifferentiated F9 cells. In contrast, CRB3, Pals1 and PATJ appeared to exhibit distinct subcellular localization in immature cells. Induced expression of HNF-4α led to translocation of these tight-junction and cell polarity proteins to beltlike tight junctions, where occludin, claudin-6 and claudin-7 were assembled, in differentiated cells. Interestingly, PAR-6, aPKC, CRB3 and Pals1, but not PAR-3 or PATJ, were also concentrated on the apical membranes in differentiated cells. These findings indicate that HNF-4α provokes not only expression of tight-junction adhesion molecules, but also modulation of subcellular distribution of junction and cell polarity proteins, resulting in junction formation and epithelial polarization

Ischemic preconditioning enhances integrity of coronary endothelial tight junctions

International Nuclear Information System (INIS)

Li, Zhao; Jin, Zhu-Qiu

2012-01-01

Highlights: ► Cardiac tight junctions are present between coronary endothelial cells. ► Ischemic preconditioning preserves the structural and functional integrity of tight junctions. ► Myocardial edema is prevented in hearts subjected to ischemic preconditioning. ► Ischemic preconditioning enhances translocation of ZO-2 from cytosol to cytoskeleton. -- Abstract: Ischemic preconditioning (IPC) is one of the most effective procedures known to protect hearts against ischemia/reperfusion (IR) injury. Tight junction (TJ) barriers occur between coronary endothelial cells. TJs provide barrier function to maintain the homeostasis of the inner environment of tissues. However, the effect of IPC on the structure and function of cardiac TJs remains unknown. We tested the hypothesis that myocardial IR injury ruptures the structure of TJs and impairs endothelial permeability whereas IPC preserves the structural and functional integrity of TJs in the blood–heart barrier. Langendorff hearts from C57BL/6J mice were prepared and perfused with Krebs–Henseleit buffer. Cardiac function, creatine kinase release, and myocardial edema were measured. Cardiac TJ function was evaluated by measuring Evans blue-conjugated albumin (EBA) content in the extravascular compartment of hearts. Expression and translocation of zonula occludens (ZO)-2 in IR and IPC hearts were detected with Western blot. A subset of hearts was processed for the observation of ultra-structure of cardiac TJs with transmission electron microscopy. There were clear TJs between coronary endothelial cells of mouse hearts. IR caused the collapse of TJs whereas IPC sustained the structure of TJs. IR increased extravascular EBA content in the heart and myocardial edema but decreased the expression of ZO-2 in the cytoskeleton. IPC maintained the structure of TJs. Cardiac EBA content and edema were reduced in IPC hearts. IPC enhanced the translocation of ZO-2 from cytosol to cytoskeleton. In conclusion, TJs occur in

Ischemic preconditioning enhances integrity of coronary endothelial tight junctions

Energy Technology Data Exchange (ETDEWEB)

Li, Zhao [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States); Jin, Zhu-Qiu, E-mail: zhu-qiu.jin@sdstate.edu [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States)

2012-08-31

Highlights: Black-Right-Pointing-Pointer Cardiac tight junctions are present between coronary endothelial cells. Black-Right-Pointing-Pointer Ischemic preconditioning preserves the structural and functional integrity of tight junctions. Black-Right-Pointing-Pointer Myocardial edema is prevented in hearts subjected to ischemic preconditioning. Black-Right-Pointing-Pointer Ischemic preconditioning enhances translocation of ZO-2 from cytosol to cytoskeleton. -- Abstract: Ischemic preconditioning (IPC) is one of the most effective procedures known to protect hearts against ischemia/reperfusion (IR) injury. Tight junction (TJ) barriers occur between coronary endothelial cells. TJs provide barrier function to maintain the homeostasis of the inner environment of tissues. However, the effect of IPC on the structure and function of cardiac TJs remains unknown. We tested the hypothesis that myocardial IR injury ruptures the structure of TJs and impairs endothelial permeability whereas IPC preserves the structural and functional integrity of TJs in the blood-heart barrier. Langendorff hearts from C57BL/6J mice were prepared and perfused with Krebs-Henseleit buffer. Cardiac function, creatine kinase release, and myocardial edema were measured. Cardiac TJ function was evaluated by measuring Evans blue-conjugated albumin (EBA) content in the extravascular compartment of hearts. Expression and translocation of zonula occludens (ZO)-2 in IR and IPC hearts were detected with Western blot. A subset of hearts was processed for the observation of ultra-structure of cardiac TJs with transmission electron microscopy. There were clear TJs between coronary endothelial cells of mouse hearts. IR caused the collapse of TJs whereas IPC sustained the structure of TJs. IR increased extravascular EBA content in the heart and myocardial edema but decreased the expression of ZO-2 in the cytoskeleton. IPC maintained the structure of TJs. Cardiac EBA content and edema were reduced in IPC hearts. IPC

Results from Tight and Loose Coupled Multiphysics in Nuclear Fuels Performance Simulations using BISON

Energy Technology Data Exchange (ETDEWEB)

S. R. Novascone; B. W. Spencer; D. Andrs; R. L. Williamson; J. D. Hales; D. M. Perez

2013-05-01

The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won’t converge and vice versa.

Results from tight and loose coupled multiphysics in nuclear fuels performance simulations using BISON

International Nuclear Information System (INIS)

Novascone, S. R.; Spencer, B. W.; Andrs, D.; Williamson, R. L.; Hales, J. D.; Perez, D. M.

2013-01-01

The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won't converge and vice versa. (authors)

Cassini-VIMS at Jupiter: Solar occultation measurements using Io

Science.gov (United States)

Formisano, V.; D'Aversa, E.; Bellucci, G.; Baines, K.H.; Bibring, J.-P.; Brown, R.H.; Buratti, B.J.; Capaccioni, F.; Cerroni, P.; Clark, R.N.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Jaumann, R.; Langevin, Y.; Matson, D.L.; McCord, T.B.; Mennella, V.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe; Chamberlain, M.C.; Hansen, G.; Hibbits, K.; Showalter, M.; Filacchione, G.

2003-01-01

We report unusual and somewhat unexpected observations of the jovian satellite Io, showing strong methane absorption bands. These observations were made by the Cassini VIMS experiment during the Jupiter flyby of December/January 2000/2001. The explanation is straightforward: Entering or exiting from Jupiter's shadow during an eclipse, Io is illuminated by solar light which has transited the atmosphere of Jupiter. This light, therefore becomes imprinted with the spectral signature of Jupiter's upper atmosphere, which includes strong atmospheric methane absorption bands. Intercepting solar light refracted by the jovian atmosphere, Io essentially becomes a "miffor" for solar occultation events of Jupiter. The thickness of the layer where refracted solar light is observed is so large (more than 3000 km at Io's orbit), that we can foresee a nearly continuous multi-year period of similar events at Saturn, utilizing the large and bright ring system. During Cassini's 4-year nominal mission, this probing tecnique should reveal information of Saturn's atmosphere over a large range of southern latitudes and times. ?? 2003 Elsevier Inc. All rights reserved.

First operations of the SOIR occultation infrared spectrometer in Venus orbit.

Science.gov (United States)

Nevejans, D.; Neefs, E.; Vandaele, A. C.; Muller, C.; Fussen, D.; Berkenbosch, S.; Clairquin, R.; Korablev, O.; Federova, A.; Bertaux, J. L.

Since May 2006, the Venus-Express spacecraft is in its nominal orbit around VENUS and the SPICAV optical package has begun to acquire spectra. The SOIR extension to SPICAV is an echelle spectrometer associated to an AOTF (Acousto-Optical Tunable Filter) for the order selection, which performs solar occultation measurements in the IR region (2.2-4.3 µm) at a resolution of 0.1 cm-1 . The detailed optical study and design as well as the manufacturing were performed at the BIRA/IASB in collaboration with its industrial partners OIP and PEDEO. It was funded by the Belgian Federal Science Policy Office under the ESA PRODEX programme. The wavelength range allows a detailed chemical inventory of the Venus atmosphere above the cloud layer with an emphasis on vertical distribution of gases. The first results look promising and will be qualitatively presented.

Internal gravity waves in Titan's atmosphere observed by Voyager radio occultation

Science.gov (United States)

Hinson, D. P.; Tyler, G. L.

1983-01-01

The radio scintillations caused by scattering from small-scale irregularities in Titan's neutral atmosphere during a radio occultation of Voyager 1 by Titan are investigated. Intensity and frequency fluctuations occurred on time scales from about 0.1 to 1.0 sec at 3.6 and 13 cm wavelengths whenever the radio path passed within 90 km of the surface, indicating the presence of variations in refractivity on length scales from a few hundred meters to a few kilometers. Above 25 km, the altitude profile of intensity scintillations closely agrees with the predictions of a simple theory based on the characteristics of internal gravity waves propagating with little or no attenuation through the vertical stratification in Titan's atmosphere. These observations support a hypothesis of stratospheric gravity waves, possibly driven by a cloud-free convective region in the lowest few kilometers of the stratosphere.