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Sample records for yellow vein streak

  1. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  2. Blackberry Yellow Vein Disease Complex

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new virus disease has emerged in the Midsouth and Southeastern United States and was named blackberry yellow vein disease (BYVD). Originally, it was thought the disease was caused by Tobacco ringspot virus (TRSV) as the virus was found in many diseased plants and symptoms were very similar to thos...

  3. Blackberry Yellow Vein Disease is Caused by Multiple Virus Complexes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackberry yellow vein disease, with symptoms of vein clearing, yellow mottling, ringspots and plant decline has been observed in blackberry in the southeastern United States since about 2000. At least six viruses have been identified by cloning and sequencing of double-stranded RNA from diseased p...

  4. Squash vein yellowing virus affecting watermelon in Puerto Rico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline outside of the continental U.S. This has implications for management of cucurbit virus diseases throughout the Caribbean....

  5. REMOTE SENSING OF BARLEY YELLOW DWARF AND WHEAT STREAK MOSAIC DISEASE IN WINTER WHEAT CANOPIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficiency of field monitoring for barley yellow dwarf (BYD) and wheat streak mosaic (WSM) viral diseases would be improved with knowledge of reflected solar radiation from winter wheat crop canopies. Our objective was to characterize canopy spectral reflectance as well as other canopy and yield...

  6. Characteristics of whitefly transmission of Squash vein yellowing virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV), a recently described ipomovirus, is transmitted by the whitefly, Bemisia tabaci Gennadius, B strain. Understanding the characteristics of transmission is essential for developing management strategies for this virus, which is the causal agent for watermelon vine ...

  7. Physiological effects of Squash vein yellowing virus infection on watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) is the cause of viral watermelon vine decline. In this study, watermelon plants of different ages were inoculated with SqVYV to characterize the physiological response to infection and provide new insights into watermelon vine decline. Physiological responses to...

  8. Squash vein yellowing virus and its effects on watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV), a novel whitefly-transmitted member of the Potyviridae was recently shown to cause a watermelon vine decline in Florida. Watermelon plants were grown under whitefly-free conditions in a greenhouse and inoculated with buffer (mock), SqVYV, or SqVYV and Papaya rin...

  9. Effects of beet necrotic yellow vein virus in spinach cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beet Necrotic Yellow Vein Virus (BNYVV) causes one of the most economically destructive sugar beet diseases, rhizomania, which may reduce sugar yield by 100%. The virus has rod shaped particles containing four to five single stranded RNAs and is transmitted by the root-infecting parasite Polymyxa be...

  10. Association of a distinct strain of hollyhock yellow vein mosaic virus and Ludwigia leaf distortion betasatellite with yellow vein mosaic disease of hollyhock (Alcea rosea) in India.

    PubMed

    Srivastava, A; Kumar, S; Raj, S K; Pande, S S

    2014-10-01

    A distinct strain of hollyhock yellow vein mosaic virus (HoYVMV) and Ludwigia leaf distortion betasatellite (LuLDB) were associated with yellow vein mosaic of hollyhock. The viral DNA genome (JQ911766) and betasatellite (JQ408216) shared highest nucleotide sequence identity (89.2 %) with HoYVMV (the only available sequence in GenBank) and 92 % identity with LuLDB. Agroinfiltration of HoYVMV and LuLDB induced yellow vein mosaic symptoms on hollyhock, thereby demonstrating causality of the disease. PMID:24810100

  11. Squash vein yellowing virus, a novel ipomovirus, isolated from squash and watermelon in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel whitefly-transmitted member of the family Potyviridae was isolated from a squash plant (Cucurbita pepo) with vein yellowing symptoms in Florida. The virus, for which the name Squash vein yellowing virus (SqVYV) is proposed, has flexuous rod-shaped particles of ~840 nm in length. SqVYV was ...

  12. Development of a multiplexed PCR detection method for Barley and Cereal Yellow Dwarf Viruses, Wheat Spindle Streak Virus, Wheat Streak Mosaic Virus and Soil-Borne Wheat Mosaic Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley and Cereal Yellow Dwarf Viruses (B/CYDVs), Wheat Spindle Streak Mosaic (WSSMV), Soil-Borne Wheat Mosaic (SBWMV) Mosaic Virus and Wheat Streak Mosaic Virus (WSMV) constitute the most economically important group of wheat viruses. In this paper, a multiplex reverse transcription polymerase chai...

  13. Association of tomato leaf curl New Delhi virus DNA-B with bhendi yellow vein mosaic virus in okra showing yellow vein mosaic disease symptoms.

    PubMed

    Venkataravanappa, V; Lakshminarayana Reddy, C N; Jalali, S; Krishna Reddy, M

    2015-06-01

    Okra samples showing yellow vein mosaic, vein twisting and bushy appearance were collected from different locations of India during the surveys conducted between years 2005-2009. The dot blot and PCR detection revealed that 75.14% of the samples were associated with monopartite begomovirus and remaining samples with bipartite virus. Whitefly transmission was established for three samples representing widely separated geographical locations which are negative to betasatellites and associated with DNA-B. Genome components of these three representative isolates were cloned and sequenced. The analysis of DNA-A-like sequence revealed that three begomovirus isolates shared more than 93% nucleotide sequence identity with bhendi yellow vein mosaic virus from India (BYVMV), a monopartite begomovirus species that was reported previously as causative agent of bhendi yellow mosaic disease in association of bhendi yellow vein mosaic betasatellite. Further, the DNA-B-like sequences associated with the three virus isolates shared no more than 90% sequence identity with tomato leaf curl New Delhi virus (ToLCNDV). Analyses of putative iteron-binding sequence required for trans-replication suggests that begomovirus sequences shared compatible rep-binding iterons with DNA-B of ToLCNDV. Our data suggest that the monopartite begomovirus associated with okra yellow vein disease has captured DNA-B of ToLCNDV to infect okra. Widespread distribution of the complex shows the increasing trend of the capturing of DNA-B of ToLCNDV by monopartite begomoviruses in the Indian subcontinent. The recombination analysis showed that the DNA-A might have been derived from the inter-specific recombination of begomoviruses, while DNA-B was derived from the ToLCNDV infecting different hosts. PMID:26104329

  14. Simplified sample preparation for detection of wheat streak mosaic virus and barley yellow dwarf virus by PCR.

    PubMed

    French, R; Robertson, N L

    1994-08-01

    A PCR diagnostic procedure for wheat streak mosaic virus (WSMV) was developed using a primer derived from 3'-terminal sequences of five WSMV isolates and an oligo d(T)-based primer. Cereal extracts prepared by digestion with proteinase K and boiling permitted PCR-based detection of both WSMV and BYDV in field samples. This procedure saves time, eliminates multiple liquid transfer steps, and reduces the chances of cross contamination. Sensitivity of such assays is still very good; BYDV could be readily detected in plant sap diluted over 1000-fold. Further, parallel detection of WSMV and barley yellow dwarf virus (BYDV) in the same samples is possible with this method. PMID:7829597

  15. Suppression of Resistance-breaking Beet Necrotic Yellow Vein Virus Isolates by Beet Oak-leaf Virus in Sugar Beet.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania, a very serious disease of sugar beet (Beta vulgaris L.), is caused by Beet necrotic yellow vein virus (BNYVV). Resistance allele Rz1 has been widely incorporated into commercial cultivars. Recently, resistance-breaking strains of Beet necrotic yellow vein virus (RB-BNYVV) were identified...

  16. Identification and characterization of Citrus yellow vein clearing virus, a putative new member of the genus Mandarivirus infecting Citrus spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow vein clearing virus, an uncharacterized filamentous virus, was first observed in Pakistan in 1988 and later in India in 1997 in Etrog citron (Citrus medica). Based on electron microscopic evidence of filamentous particles, the virus, provisionally named Citrus yellow vein clearing virus (CYVC...

  17. Influence of beet necrotic yellow vein virus on sugar beet storability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious sugar beet production problems. To investigate the influence of BNYVV on storability, six sugar beet cultivars varying for resistance to BNYVV were grown in 2005 and 2006 in southern Idaho fields with and wi...

  18. Squash vein yellowing virus infection of vining cucurbits and the vine decline response

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) is the cause of viral watermelon vine decline. In this study, the responses of a diverse group of vining cucurbits to SqVYV inoculation was determined. The majority of cucurbits tested had either no symptoms of infection, or developed relatively mild symptoms. ...

  19. Molecular characterization and population structure of a new ampelovirus associated with blackberry yellow vein disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackberry yellow vein disease is the most important viral disease of blackberry in the United States. Experiments were conducted to characterize a new virus identified in symptomatic plants. Molecular analysis revealed a genome organization resembling Grapevine leafroll-associated virus 3, the type...

  20. Sugar beet storability and the influence of beet necrotic yellow vein virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania in sugar beets caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious problems in sugar beet production. Storage issues associated with outdoor piles may be exacerbated by disease problems such as rhizomania. To investigate the influence of BNYVV on storability...

  1. NUCLEOTIDE SEQUENCE OF BLACKBERRY YELLOW VEIN ASSOCIATED VIRUS, A NOVEL MEMBER OF THE CLOSTEROVIRIDAE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The complete nucleotide sequence of a novel member of the genus Crinivirus (family Closteroviridae), isolated from blackberry and tentatively named Blackberry yellow vein associated virus, was determined. The virus possesses a bipartite genome. RNA 1 is 7801 nucleotides in length and papain-like pro...

  2. YELLOW VEIN-AFFECTED BLACKBERRIES AND THE PRESENCE OF A NOVEL CRINIVIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the last five years, blackberry plants in Arkansas, North Carolina and South Carolina exhibited virus-like symptoms of vein yellowing and mosaic, followed in some cases by death. Diagnostic tests for known blackberry viruses failed to identify a causal agent. Double-stranded RNA was extracte...

  3. Responses of various vining cucurbits to Squash vein yellowing virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) induced watermelon vine decline is a major limitation to watermelon production in Florida. The symptoms of this disease are a systemic wilt and necrosis which spreads along the vines of plants and leads to complete collapse. Fruit on affected vines also often sh...

  4. First report of Beet necrotic yellow vein virus infecting spinach in California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2009, plants from two spinach (Spinacia oleracea) experimental fields in Monterey County and one commercial spinach field in Ventura County of California exhibited vein clearing, mottling, interveinal yellowing and stunting symptoms. For experimental fields, up to 44% of spinach plants were infec...

  5. Development of ELISA and qPCR for Squash vein yellowing virus detection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon vine decline caused by Squash vein yellowing virus (SqVYV) is a new and emerging disease that has caused severe losses to Florida watermelon growers in recent years. First identified in 2005, SqVYV is widely distributed in southwest and west-central Florida and has recently been found in...

  6. Inheritance of resistance to Okra yellow vein mosaic disease in interspecific crosses of Abelmoschus.

    PubMed

    Jambhale, N D; Nerkar, Y S

    1981-09-01

    Two Abelmoschus species, viz., A. manihot (L.) Medik and A. manihot (L.) Medik ssp. manihot, resistant to Okra yellow vein mosaic (YVM) were crossed to A. esculentus cv. 'Pusa Sawani', a susceptible culture. The hybrids were resistant and partially fertile. Segregation pattern for disease reaction in F2, BC1 and subsequent generations of the two crosses revealed that resistance to YVM is controlled by a single dominant gene in each species. PMID:24276872

  7. Ageratum yellow vein China virus Is a Distinct Begomovirus Species Associated with a DNAbeta Molecule.

    PubMed

    Xiong, Qing; Fan, Sanwei; Wu, Jianxiang; Zhou, Xueping

    2007-04-01

    ABSTRACT Ageratum conyzoides plants exhibiting yellow vein symptoms, collected near Haikou, Hainan Province, China, contained begomoviral DNA-A-like molecules. The complete sequences of the molecules from two samples, Hn2 and Hn2-19, were shown to consist of 2,768 and 2,748 nucelotides (nt), respectively. These sequences have more than 97% nucleotide sequence identity, but less than 86% identity with other reported begomovirus sequences. In line with the taxonomic convention for begomoviruses, Hn2 and Hn2-19 are therefore considered to represent isolates of a distinct begomovirus species, for which the name Ageratum yellow vein China virus (AYVCNV) is proposed. Sequence alignment shows AYVCNV has arisen by recombination among viruses related to Ageratum yellow vein virus, Papaya leaf curl China virus, and an unidentified begomovirus. Southern blot analyses revealed that all plants sampled contained molecules resembling DNAbeta. DNAbeta molecules from three samples were 1,323 or 1,324 nt long and had >98% sequence identity but <81% identity with previously reported DNAbeta sequences. Infectious clones of Hn2 and its associated DNAbeta were constructed and agroinoculated to plants. Hn2 alone caused sporadic asymptomatic systemic infection of Nicotiana benthamiana, N. glutinosa, Lycopersicon esculentum, Petunia hybrida, and A. conyzoides but its accumulation was much enhanced in plants co-inoculated with DNAbeta. The co-inoculated N. benthamiana, N. glutinosa, P. hybrida, and L. esculentum plants developed leaf curling or leaf crinkling symptom; those in A. conyzoides were typical of ageratum yellow vein disease. When the DNAbeta molecules associated with four other Chinese begomoviruses were coinoculated with Hn2 to N. benthamiana and N. glutinosa, the DNAbeta molecules were replicated, and the plants developed systemic symptoms of types that were specific for each DNAbeta. This illustrates that there is less specific interaction between monopartite begomovirus and DNAbeta than between the DNA-A and DNA-B of begomoviruses with bipartite genomes. PMID:18943280

  8. Bhendi yellow vein mosaic disease in India is caused by association of a DNA Beta satellite with a begomovirus.

    PubMed

    Jose, Joyce; Usha, Ramakrishnan

    2003-01-20

    Yellow vein mosaic disease is the major limitation in the production of bhendi or okra (Abelmoschus esculentus), an important vegetable crop of India. This disease is caused by a complex consisting of the monopartite begomovirus Bhendi yellow vein mosaic virus (BYVMV, family: Geminiviridae) and a small satellite DNA beta component. BYVMV can systemically infect bhendi upon agroinoculation but produces only mild leaf curling in this host. DNA beta induces typical symptoms of bhendi yellow vein mosaic disease (BYVMD) when co-agroinoculated with the begomovirus to bhendi. The DNA beta component associated with BYVMD has a number of features in common with those reported for ageratum yellow vein disease and cotton leaf curl disease. BYVMV represents a new member of the emerging group of monopartite begomoviruses requiring a satellite component for symptom induction. PMID:12573576

  9. Complete nucleotide sequences of a distinct bipartite begomovirus, bitter gourd yellow vein virus, infecting Momordica charantia.

    PubMed

    Tahir, Muhammad; Haider, Muhammad Saleem; Briddon, Rob W

    2010-11-01

    Momordica charantia (Cucurbitaceae), a vegetable crop commonly cultivated throughout Pakistan, and begomoviruses, a serious threat to crop plants, are natives of tropical and subtropical regions of the world. Leaf samples of M. charantia with yellow vein symptoms typical of begomovirus infections and samples from apparently healthy plants were collected from areas around Lahore in 2004. Full-length clones of a bipartite begomovirus were isolated from symptomatic samples. The complete nucleotide sequences of the components of one isolate were determined, and these showed the arrangement of genes typical of Old World begomoviruses. The complete nucleotides sequence of DNA A showed the highest nucleotide sequence identity (86.9%) to an isolate of Tomato leaf curl New Delhi virus (ToLCNDV), confirming it to belong to a distinct species of begomovirus, for which the name Bitter gourd yellow vein virus (BGYVV) is proposed. Sequence comparisons showed that BGYVV likely emerged as a result of inter-specific recombination between ToLCNDV and tomato leaf curl Bangladesh virus (ToLCBDV). The complete nucleotide sequence of DNA B showed 97.2% nucleotide sequence identity to that of an Indian strain of Squash leaf curl China virus. PMID:20924621

  10. Dissecting the epidemiology of Blackberry yellow vein associated virus and Blackberry chlorotic ringspot virus; a study on population structure, transmission, and alternative hosts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackberry yellow vein disease (BYVD), a disorder caused by virus complexes is the most important blackberry disease in the southern United States. Blackberry yellow vein associated virus (BYVaV) is the most prevalent virus in BYVD plants being detected in more than 50% of the samples exhibiting BYV...

  11. Molecular characterization of a citrus yellow vein clearing virus strain from China.

    PubMed

    Zhen, Song; Kurth, Elizabeth G; Peremyslov, Valera V; Changyong, Zhou; Dolja, Valerian V

    2015-07-01

    The complete nucleotide sequence of an isolate of citrus yellow vein clearing virus from Yunnan, China (CYVCV-RL), was determined following whole-genome amplification by RT-PCR. The CYVCV-RL genome was 7529 nt in length, excluding the 3' poly (A) tail, and contained six open reading frames (ORFs), resembling that of viruses belonging to the genus Mandarivirus in the family Alphaflexiviridae. Sequence analysis showed that the CYVCV-RL shared the greatest nucleotide sequence identity with the CYVCV-Y1 (JX040635) isolate from Turkey for the whole genome (97.1%), 5' UTR (98.7%), 3' UTR (100.0%), and each of six ORFs (96.5% to 97.8%), suggesting that there is apparent genetic stability among CYVCV isolates of different geographic origin. PMID:25913691

  12. Corchorus yellow vein virus, a New World geminivirus from the Old World.

    PubMed

    Ha, Cuong; Coombs, Steven; Revill, Peter; Harding, Rob; Vu, Man; Dale, James

    2006-04-01

    A bipartite begomovirus infecting Jute mallow (Corchorus capsularis, Tilliaceae) in Vietnam was identified using novel degenerate PCR primers. Analysis of this virus, which was named Corchorus yellow vein virus (CoYVV), showed that it was more similar to New World begomoviruses than to viruses from the Old World. This was based on the absence of an AV2 open reading frame, the presence of an N-terminal PWRLMAGT motif in the coat protein and phylogenetic analysis of the DNA A and DNA B nucleotide and deduced amino acid sequences. Evidence is provided that CoYVV is probably indigenous to the region and may be the remnant of a previous population of New World begomoviruses in the Old World. PMID:16528050

  13. Progress and Challenges in Managing Watermelon Vine Decline caused by whitefly transmitted Squash Vein Yellowing Virus (SqVYV)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon vine decline (WVD) is an emerging threat to watermelon production in south-west and west-central Florida. Losses in 2004-2005 due to WVD were estimated to be more than 60 million U.S. dollars. The disease is caused by Squash vein yellowing virus (SqVYV), family: Potyviridae, genus: Ip...

  14. Performance of rhizomania resistant sugarbeet under normal and resistance-breaking strains of Beet necrotic yellow vein virus.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania in sugarbeet (Beta vulgaris) is caused by Beet necrotic yellow vein virus (BNYVV). In current commercial cultivars, resistance to BNYVV is conditioned primarily by the allele Rz1. Since 2003, observations indicate that Rz1 has been compromised by resistance-breaking strains of BNYVV (RB-B...

  15. Differentiating Rz-1 AND Rz-2 resistance reactions to Beet necrotic yellow vein virus through proteome analysis in sugar beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is one of the most economically important diseases affecting sugarbeet, and is widely distributed in most sugarbeet growing areas of the world. Control is achieved almost exclusively through planting of resistant varieties. Following t...

  16. Squash vein yellowing virus detection using nested polymerase chain reaction demonstrates Momordica charantia is a reservoir host

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) is a recently described ipomovirus from cucurbits in Florida that induces the relatively unusual symptoms in watermelon of plant death and fruit rind necrosis and discoloration, commonly known in Florida as watermelon vine decline. In this report, we demonstrate ...

  17. Sources of Resistance in U.S. Plant Introductions to Watermelon Vine Decline Caused of Squash Vein Yellowing Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon vine decline (WVD) caused by the whitefly-transmitted (Bemisia tabaci) Squash vein yellowing virus (SqVYV; genus Ipomovirus, family: Potyviridae) has become a major limiting factor in watermelon (Citrullus lanatus) production in southwest and west-central Florida in recent years. Sympto...

  18. Effect of reflective mulch and insecticidal treatments on development of watermelon vine decline caused by squash vein yellowing virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vine decline (WVD) caused by the whitefly transmitted Squash vein yellowing virus (SqVYV) has been a major limiting factor in watermelon (Citrullus lanatus) production in southwest and west-central Florida for the past several years. Symptoms of WVD typically manifest as sudden decline of vines one...

  19. Development and evaluation of quanitative early monitoring techniques for Squash vein yellowing virus, the cause of watermelon vine decline

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon vine decline caused by whitefly-transmitted Squash vein yellowing virus (SqVYV) is an emerging disease that has caused severe losses to Florida watermelon growers in recent years. Although the late stage symptoms of watermelon vine decline are basically diagnostic for the presence of SqV...

  20. DISTRIBUTION AND MOLECULAR ANALYSIS OF RESISTANCE-BREAKING ISOLATES OF BEET NECROTIC YELLOW VEIN VIRUS IN THE UNITED STATES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania is one of the most economically important diseases of sugar beet. It is caused by Bee necrotic yellow vein virus (BNYVV) and is vectored by the plasmodiophorid Polymyxa betae. The disease can only be controlled effectively by the use of resistant cultivars. In 2003, the resistance-breakin...

  1. Physiological effects induced by Squash vein yellowing virus, causal agent of viral watermelon vine decline in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whitefly-transmitted Squash vein yellowing virus (SqVYV) was recently shown to cause a watermelon vine decline that has had significant economic impact on watermelon production in southwest and west-central Florida during the past six years. Symptoms typically appear as a sudden decline of vines at...

  2. Influence of insecticides and reflective mulch on watermelon vine decline caused by squash vein yellowing virus (SqVYV)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon vine decline (WVD) caused by the whitefly-transmitted Squash vein yellowing virus (SqVYV) has been a major limiting factor in watermelon production in southwest and west-central Florida for the past several years. Symptoms of WVD typically manifest as sudden decline of vines a few weeks ...

  3. Distribution and molecular characterization of resistance-breaking isolates of Beet necrotic yellow vein virus in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beet necrotic yellow vein virus (BNYVV) is the causal agent of rhizomania disease of sugar beet (Beta vulgaris L.). The virus is transmitted by the plasmodiophorid Polymyxa betae. The disease can only be controlled effectively by the use of partially resistant cultivars. During 2003 and 2004 in the ...

  4. Complete genome sequence of nine isolates of canna yellow streak virus reveals its relationship to the sugarcane mosaic virus (SCMV) subgroup of potyviruses.

    PubMed

    Chauhan, Ravendra P; Rajakaruna, Punsasi; Verchot, Jeanmarie

    2015-03-01

    Complete genome sequences were obtained from nine isolates of canna yellow streak virus (CaYSV). CaYSV belongs to the sugarcane mosaic virus (SCMV) subgroup of potyviruses with johnsongrass mosaic virus (JGMV) as its closest relative. Multiple sequence alignments showed a pattern of amino acid substitutions in the CP sequences, which enabled us to relate these isolates to South East Asian or European isolates. Biological characterization of CaYSV identified Nicotiana benthamiana, Chenopodium quinoa and Phaseolus vulgaris as experimental hosts. Given the popularity and global trade of cannas, a clear picture of the genetic diversity of CaYSV is critical to disease management. PMID:25567205

  5. A review of ipomoviruses and watermelon vine decline caused by the newly-described and whitefly-transmitted squash vein yellowing virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Though few in number, ipomoviruses cause significant disease in cucurbits and other crops in various parts of the world. As the causal agent of watermelon vine decline in Florida, Squash vein yellowing virus has recently become an economically important pathogen....

  6. Rapid screening of RNA silencing suppressors by using a recombinant virus derived from beet necrotic yellow vein virus.

    PubMed

    Guilley, H; Bortolamiol, D; Jonard, G; Bouzoubaa, S; Ziegler-Graff, V

    2009-10-01

    To counteract plant defence mechanisms, plant viruses have evolved to encode RNA silencing suppressor (RSS) proteins. These proteins can be identified by a range of silencing suppressor assays. Here, we describe a simple method using beet necrotic yellow vein virus (BNYVV) that allows a rapid screening of RSS activity. The viral inoculum consisted of BNYVV RNA1, which encodes proteins involved in viral replication, and two BNYVV-derived replicons: rep3-P30, which expresses the movement protein P30 of tobacco mosaic virus, and rep5-X, which allows the expression of a putative RSS (X). This approach has been validated through the use of several known RSSs. Two potential candidates have been tested and we show that, in our system, the P13 protein of burdock mottle virus displays RSS activity while the P0 protein of cereal yellow dwarf virus-RPV does not. PMID:19570958

  7. Rapid detection of cucumber vein yellowing virus by tissue-print hybridisation with digoxigenin-labelled cDNA probes.

    PubMed

    Rubio, L; Janssen, D; Cuadrado, I M; Moreno, P; Guerri, J

    2003-12-01

    Hybridisation of tissue prints with nonradioactive cDNA probes was developed to detect cucumber vein yellowing virus (CVYV) in cucurbit plants. Results showed irregular distribution of the virus within cucumber, zucchini or melon plants without defined tropism for a specific tissue. Therefore, reliable diagnosis of CVYV requires analysis of tissue prints from at least five different plant sites. This detection procedure allows rapid analysis of large numbers of plants and it can be useful for epidemiological studies of CVYV and to control virus spread via eradication of early foci. PMID:14599685

  8. Immunodetection of beet necrotic yellow vein virus RNA3-encoded protein in different host plants and tissues.

    PubMed

    Li, Y; Wei, C; Tien, P; Pan, N; Chen, Z

    1996-04-01

    The protein p25 open reading frame (ORF) of beet necrotic yellow vein virus-BNYVV RNA3 was cloned into bacterial expression vector downstream of the 5-'terminus part of beta-galactosidase ORF and the expressed p25 fusion protein was used to produce an antiserum. The latter was employed to detect the subcellular location of p25 in mechanically inoculated Tetragonia expansa, Chenopodium quinoa and sugarbeet leaves by Western blot assay. The results showed that p25 was present as a soluble protein only in the S30 fraction of T. expansa, C. quinoa and sugarbeet leaves infected with BNYVV. PMID:8886114

  9. Host range and genetic diversity of croton yellow vein mosaic virus, a weed-infecting monopartite begomovirus causing leaf curl disease in tomato.

    PubMed

    Pramesh, D; Mandal, Bikash; Phaneendra, Chigurupati; Muniyappa, V

    2013-03-01

    Croton yellow vein mosaic virus (CYVMV) is a widely occurring begomovirus in Croton bonplandianum, a common weed in the Indian subcontinent. In this study, CYVMV (genus Begomovirus, family Geminiviridae) was transmitted by whiteflies (Bemisia tabaci) to as many as 35 plant species belonging to 11 families, including many vegetables, tobacco varieties, ornamentals and weeds. CYVMV produced bright yellow vein symptoms in croton, whereas in all the other host species, the virus produced leaf curl symptoms. CYVMV produced leaf curl in 13 tobacco species and 22 cultivars of Nicotiana tabacum and resembled tobacco leaf curl virus (TobLCV) in host reactions. However, CYVMV was distinguished from TobLCV in four differential hosts, Ageratum conyzoides, C. bonplandianum, Euphorbia geniculata and Sonchus bracyotis. The complete genome sequences of four isolates originating from northern, eastern and southern India revealed that a single species of DNA-A and a betasatellite, croton yellow vein mosaic betasatellite (CroYVMB) were associated with the yellow vein mosaic disease of croton. The sequence identity among the isolates of CYVMV DNA-A and CroYVMB occurring in diverse plant species was 91.8-97.9 % and 83.3-100 %, respectively. The CYVMV DNA-A and CroYVMB generated through rolling-circle amplification of the cloned DNAs produced typical symptoms of yellow vein mosaic and leaf curling in croton and tomato, respectively. The progeny virus from both the croton and tomato plants was transmitted successfully by B. tabaci. The present study establishes the etiology of yellow vein mosaic disease of C. bonplandianum and provides molecular evidence that a weed-infecting monopartite begomovirus causes leaf curl in tomato. PMID:23096697

  10. Two Resistance Modes to Clover yellow vein virus in Pea Characterized by a Green Fluorescent Protein-Tagged Virus.

    PubMed

    Andrade, Marcelo; Sato, Masanao; Uyeda, Ichiro

    2007-05-01

    ABSTRACT This study characterized resistance in pea lines PI 347295 and PI 378159 to Clover yellow vein virus (ClYVV). Genetic cross experiments showed that a single recessive gene controls resistance in both lines. Conventional mechanical inoculation did not result in infection; however, particle bombardment with infectious plasmid or mechanical inoculation with concentrated viral inocula did cause infection. When ClYVV No. 30 isolate was tagged with a green fluorescent protein (GFP) and used to monitor infection, viral cell-to-cell movement differed in the two pea lines. In PI 347595, ClYVV replicated at a single-cell level, but did not move to neighboring cells, indicating that resistance operated at a cell-to-cell step. In PI 378159, the virus moved to cells around the infection site and reached the leaf veins, but viral movement was slower than that in the susceptible line. The viruses observed around the infection sites and in the veins were then recovered and inoculated again by a conventional mechanical inoculation method onto PI 378159 demonstrating that ClYVV probably had mutated and newly emerged mutant viruses can move to neighboring cells and systemically infect the plants. Tagging the virus with GFP was an efficient tool for characterizing resistance modes. Implications of the two resistance modes are discussed. PMID:18943572

  11. The complete genome sequences of two isolates of cnidium vein yellowing virus, a tentative new member of the family Secoviridae.

    PubMed

    Yoo, Ran Hee; Zhao, Fumei; Lim, Seungmo; Igori, Davaajargal; Kim, Sang-Mok; An, Tae-Jin; Lee, Su-Heon; Moon, Jae Sun

    2015-11-01

    We determined the complete genome sequences of two isolates of cnidium vein yellowing virus (CnVYV-1 and -2) that co-infected all field samples collected from Cnidium officinale in Korea. Unlike CnVYV-2, however, CnVYV-1 was sap-transmissible to Nicotiana benthamiana. CnVYV-1 and -2 have bipartite genomes of 7,263 and 3,110 nucleotides and 7,278 and 3,112 nucleotides, respectively, excluding the poly(A) tails. Phylogenetic analysis of the CnVYV-1 and -2 sequences indicated close relationships to strawberry latent ringspot virus, an unassigned member of the family Secoviridae. CnVYV-1 and CnVYV-2 are closely related viruses that may represent a tentative new species of the family Secoviridae. PMID:26282235

  12. The Use of Latent Class Analysis to Estimate the Sensitivities and Specificities of Diagnostic Tests for Squash vein yellowing virus in Cucurbit Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) is the causal agent of viral watermelon vine decline, one of the most serious diseases in watermelon (Citrullus lanatus L.) production in the southeastern United States. Current diagnostic methods for identification of SqVYV-infected plants or tissues are based on...

  13. Identification of plant reservoirs and genome characterization of Squash vein yellowing virus, causal agent of viral watermelon vine decline in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) was identified in cucurbits in Florida in 2005 and shown to be whitefly-transmissible and to induce a previously observed watermelon vine decline and fruit rind necrosis. Only cucurbits have been determined to be hosts for SqVYV so common cucurbit weeds in south ...

  14. Presence of P1b and absence of HC-Pro in Squash vein yellowing virus suggests a general feature of the genus Ipomovirus in the family Potyviridae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Ipomovirus is one of six currently recognized genera in the family Potyviridae. The complete nucleotide sequence of Squash vein yellowing virus (SqVYV), a putative ipomovirus recently described in Florida, has been determined. The SqVYV genomic RNA has one large open reading frame encoding...

  15. 392291-VDR, a watermelon germplasm line with resistance to Squash vein yellowing virus (SqVYV)-caused watermelon vine decline (WVD)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    392291-VDR (vine decline resistant) is a watermelon (Citrullus lanatus var. lanatus) germplasm line having resistance to watermelon vine decline (WVD) caused by the whitefly transmitted Squash vein yellowing virus (SqVYV). The line is derived from the U.S. Plant Introduction (PI) 392291, after succ...

  16. Squash vein yellowing virus, causal agent of viral watermelon vine decline in Florida, USA – reservoirs, genome characterization and mixed infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) was identified in cucurbits in Florida in 2005, shown to be whitefly-transmissible and to induce a previously observed watermelon vine decline and fruit rind necrosis. SqVYV has been isolated from declining watermelons for the past six growing seasons in southwes...

  17. Rhizomania as seen from inside the beet cell: Identifying proteome differences between sugarbeet infected with Beet necrotic yellow vein virus and healthy sugarbeet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV) is one of the most economically important diseases affecting sugarbeet. The disease is characterized by excessive growth of lateral roots and constriction of the taproot, the main sucrose storage site in sugarbeet, resulting in decreased ...

  18. Use of latent class analysis to estimate the sensitivities and specificities of diagnostic tests for Squash vein yellowing virus in cucurbits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Squash vein yellowing virus (SqVYV) causes watermelon vine decline in watermelon (Citrullus lanatus var. lanatus). Current methods for identification of SqVYV-infected plants are based on the polymerase chain reaction (RT-PCR), tissue blot nucleic acid hybridization assays (NAHA), and visual symptom...

  19. Blackberry Virus Y is a Member of a New Genus in the Family Potyviridae and a Contributing Component of Blackberry yellow vein disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new virus, designated as Blackberry virus Y (BVY), isolated from blackberries exhibiting symptoms of the blackberry yellow vein disease (BYVD) has been identified. The complete nucleotide sequence of BVY has been determined and it revealed several unique features for a member of the Potyviridae fa...

  20. A resistance gene in common bean to Clover yellow vein virus is tightly linked with bc-3 gene which confers resistance to Bean common mosaic virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A strain of Clover yellow vein virus (ClYVV) that causes severe mosaic, top necrosis, stunting, and pod necrosis on infected plants has been plaguing snap bean production in the Great Lakes and Northeastern regions of the US since 2003. In preliminary virus screening experiments to identify resistan...

  1. Association of a recombinant Cotton leaf curl Bangalore virus with yellow vein and leaf curl disease of okra in India.

    PubMed

    Venkataravanappa, V; Lakshminarayana Reddy, C N; Devaraju, A; Jalali, Salil; Krishna Reddy, M

    2013-09-01

    A begomovirus isolate (OY136A) collected from okra plants showing upward leaf curling, vein clearing, vein thickening and yellowing symptoms from Bangalore rural district, Karnataka, India was characterized. The sequence comparisons revealed that, this virus isolate share highest nucleotide identity with isolates of Cotton leaf curl Bangalore virus (CLCuBV) (AY705380) (92.8%) and Okra enation leaf curl virus (81.1-86.2%). This is well supported by phylogentic analysis showing, close clustering of the virus isolate with CLCuBV. With this data, based on the current taxonomic criteria for the genus Begomovirus, the present virus isolate is classified as a new strain of CLCuBV, for which CLCuBV-[India: Bangalore: okra: 2006] additional descriptor is proposed. The betasatellite (KC608158) associated with the virus is having more than 95% sequence similarity with the cotton leaf curl betasatellites (CLCuB) available in the GenBank.The recombination analysis suggested, emergence of this new strain of okra infecting begomovirus might have been from the exchange of genetic material between BYVMV and CLCuMuV. The virus was successfully transmitted by whitefly and grafting. The host range of the virus was shown to be very narrow and limited to two species in the family Malvaceae, okra (Abelmoschus esculentus) and hollyhock (Althaea rosea), and four in the family Solanaceae. PMID:24426275

  2. Beet necrotic yellow vein virus accumulates inside resting spores and zoosporangia of its vector Polymyxa betae BNYVV infects P. betae

    PubMed Central

    Lubicz, Jeanmarie Verchot; Rush, Charles M; Payton, Mark; Colberg, Terry

    2007-01-01

    Background Plasmodiophorids and chytrids are zoosporic parasites of algae and land plant and are distributed worldwide. There are 35 species belonging to the order Plasmodiophorales and three species, Polymyxa betae, P. graminis, and Spongospora subterranea, are plant viral vectors. Plasmodiophorid transmitted viruses are positive strand RNA viruses belonging to five genera. Beet necrotic yellow vein virus (BNYVV) and its vector, P. betae, are the causal agents for rhizomania. Results Evidence of BNYVV replication and movement proteins associating with P. betae resting spores was initially obtained using immunofluorescence labeling and well characterized antisera to each of the BNYVV proteins. Root cross sections were further examined using immunogold labeling and electron microscopy. BNYVV proteins translated from each of the four genomic and subgenomic RNAs accumulate inside P. betae resting spores and zoospores. Statistical analysis was used to determine if immunolabelling detected viral proteins in specific subcellular domains and at a level greater than in control samples. Conclusion Virus-like particles were detected in zoosporangia. Association of BNYVV replication and movement proteins with sporangial and sporogenic stages of P. betae suggest that BNYVV resides inside its vector during more than one life cycle stage. These data suggest that P. betae might be a host as well as a vector for BNYVV PMID:17411435

  3. Transcriptome Analysis of Beta macrocarpa and Identification of Differentially Expressed Transcripts in Response to Beet Necrotic Yellow Vein Virus Infection

    PubMed Central

    Fan, Huiyan; Zhang, Yongliang; Sun, Haiwen; Liu, Junying; Wang, Ying; Wang, Xianbing; Li, Dawei; Yu, Jialin; Han, Chenggui

    2015-01-01

    Background Rhizomania is one of the most devastating diseases of sugar beet. It is caused by Beet necrotic yellow vein virus (BNYVV) transmitted by the obligate root-infecting parasite Polymyxa betae. Beta macrocarpa, a wild beet species widely used as a systemic host in the laboratory, can be rub-inoculated with BNYVV to avoid variation associated with the presence of the vector P. betae. To better understand disease and resistance between beets and BNYVV, we characterized the transcriptome of B. macrocarpa and analyzed global gene expression of B. macrocarpa in response to BNYVV infection using the Illumina sequencing platform. Results The overall de novo assembly of cDNA sequence data generated 75,917 unigenes, with an average length of 1054 bp. Based on a BLASTX search (E-value ≤ 10−5) against the non-redundant (NR, NCBI) protein, Swiss-Prot, the Gene Ontology (GO), Clusters of Orthologous Groups of proteins (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, there were 39,372 unigenes annotated. In addition, 4,834 simple sequence repeats (SSRs) were also predicted, which could serve as a foundation for various applications in beet breeding. Furthermore, comparative analysis of the two transcriptomes revealed that 261 genes were differentially expressed in infected compared to control plants, including 128 up- and 133 down-regulated genes. GO analysis showed that the changes in the differently expressed genes were mainly enrichment in response to biotic stimulus and primary metabolic process. Conclusion Our results not only provide a rich genomic resource for beets, but also benefit research into the molecular mechanisms of beet- BNYV Vinteraction. PMID:26196682

  4. Daedalia Streak

    NASA Technical Reports Server (NTRS)

    2005-01-01

    1 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark wind streak formed in the lee of a crater in Daedalia Planum. The winds responsible for the streak blew from right (east) to left (west).

    Location near: 11.7oS, 136.4oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  5. Daedalia Streak

    NASA Technical Reports Server (NTRS)

    2004-01-01

    26 April 2004 This April 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark wind streak on the lee (downwind) side of a small meteor impact crater in western Daedalia Planum. The substrate in this region consists of large lava flows (larger than the image shown here). The winds responsible for the streak came from the east/northeast (right). This picture is located near 15.4oS, 138.1oW, and covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

  6. Chryse Streak

    NASA Technical Reports Server (NTRS)

    2006-01-01

    6 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a wind streak created in the lee -- the downwind side -- of a crater in far eastern Chryse Planitia. The winds responsible for the formation of the streak blew from the upper right (northeast) to the lower left (southwest).

    Location near: 21.5oN, 27.4oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  7. Argyre Streaks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    26 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of dark streaks created by spring and summer dust devil activity in Argyre Planitia.

    Location near: 47.3oS, 39.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  8. Crater Streaks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    2 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows impact craters and wind streaks in Daedalia Planum.

    Location near: 14.6oS, 131.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Winter

  9. Analysis of the RNA of Potato yellow vein virus: evidence for a tripartite genome and conserved 3'-terminal structures among members of the genus Crinivirus.

    PubMed

    Livieratos, I C; Eliasco, E; Müller, G; Olsthoorn, R C L; Salazar, L F; Pleij, C W A; Coutts, R H A

    2004-07-01

    Double-stranded RNA preparations produced from potato plants graft-inoculated with a Peruvian isolate of Potato yellow vein virus (PYVV; genus Crinivirus, family Closteroviridae) contain five RNA species denoted RNA 1, RNA 2, RNA 3, x and y of approximately 8, 5.3, 3.8, 2.0 and 1.8 kbp, respectively. The complete nucleotide sequences of PYVV RNAs 1, 2 and 3 and Northern hybridization analysis showed that PYVV RNA 1 contained the replication module and an additional open reading frame (p7), while two distinct species, RNAs 2 and 3, contain the Closteroviridae hallmark gene array. Pairwise comparisons and phylogeny of genome-encoded proteins showed that PYVV shares significant homology with other criniviruses but is most closely related to the Trialeurodes vaporariorum-vectored Cucumber yellows virus. Secondary structure prediction of the 3'-untranslated regions of all three PYVV RNAs revealed four conserved stem-loop structures and a 3'-terminal pseudoknot structure, also predicted for all fully characterized members of the genus Crinivirus and some members of the genera Closterovirus and Ampelovirus. PMID:15218192

  10. Complete genome sequence of a Chinese isolate of pepper vein yellows virus and evolutionary analysis based on the CP, MP and RdRp coding regions.

    PubMed

    Liu, Maoyan; Liu, Xiangning; Li, Xun; Zhang, Deyong; Dai, Liangyin; Tang, Qianjun

    2016-03-01

    The genome sequence of pepper vein yellows virus (PeVYV) (PeVYV-HN, accession number KP326573), isolated from pepper plants (Capsicum annuum L.) grown at the Hunan Vegetables Institute (Changsha, Hunan, China), was determined by deep sequencing of small RNAs. The PeVYV-HN genome consists of 6244 nucleotides, contains six open reading frames (ORFs), and is similar to that of an isolate (AB594828) from Japan. Its genomic organization is similar to that of members of the genus Polerovirus. Sequence analysis revealed that PeVYV-HN shared 92 % sequence identity with the Japanese PeVYV genome at both the nucleotide and amino acid levels. Evolutionary analysis based on the coat protein (CP), movement protein (MP), and RNA-dependent RNA polymerase (RdRP) showed that PeVYV could be divided into two major lineages corresponding to their geographical origins. The Asian isolates have a higher population expansion frequency than the African isolates. Negative selection and genetic drift (founder effect) were found to be the potential drivers of the molecular evolution of PeVYV. Moreover, recombination was not the distinct cause of PeVYV evolution. This is the first report of a complete genomic sequence of PeVYV in China. PMID:26620586

  11. NAC transcription factor family genes are differentially expressed in rice during infections with Rice dwarf virus, Rice black-streaked dwarf virus, Rice grassy stunt virus, Rice ragged stunt virus, and Rice transitory yellowing virus.

    PubMed

    Nuruzzaman, Mohammed; Sharoni, Akhter M; Satoh, Kouji; Karim, Mohammad Rezaul; Harikrishna, Jennifer A; Shimizu, Takumi; Sasaya, Takahide; Omura, Toshihiro; Haque, Mohammad A; Hasan, Sayed M Z; Ahmad, Aziz; Kikuchi, Shoshi

    2015-01-01

    Expression levels of the NAC gene family were studied in rice infected with Rice dwarf virus (RDV), Rice black-streaked dwarf virus (RBSDV), Rice grassy stunt virus (RGSV), Rice ragged stunt virus (RRSV), and Rice transitory yellowing virus (RTYV). Microarray analysis showed that 75 (68%) OsNAC genes were differentially regulated during infection with RDV, RBSDV, RGSV, and RRSV compared with the control. The number of OsNAC genes up-regulated was highest during RGSV infection, while the lowest number was found during RTYV infection. These phenomena correlate with the severity of the syndromes induced by the virus infections. Most of the genes in the NAC subgroups NAC22, SND, ONAC2, ANAC34, and ONAC3 were down-regulated for all virus infections. These OsNAC genes might be related to the health stage maintenance of the host plants. Interestingly, most of the genes in the subgroups TIP and SNAC were more highly expressed during RBSDV and RGSV infections. These results suggested that OsNAC genes might be related to the responses induced by the virus infection. All of the genes assigned to the TIP subgroups were highly expressed during RGSV infection when compared with the control. For RDV infection, the number of activated genes was greatest during infection with the S-strain, followed by the D84-strain and the O-strain, with seven OsNAC genes up-regulated during infection by all three strains. The Os12g03050 and Os11g05614 genes showed higher expression during infection with four of the five viruses, and Os11g03310, Os11g03370, and Os07g37920 genes showed high expression during at least three viral infections. We identified some duplicate genes that are classified as neofunctional and subfunctional according to their expression levels in different viral infections. A number of putative cis-elements were identified, which may help to clarify the function of these key genes in network pathways. PMID:26442000

  12. NAC transcription factor family genes are differentially expressed in rice during infections with Rice dwarf virus, Rice black-streaked dwarf virus, Rice grassy stunt virus, Rice ragged stunt virus, and Rice transitory yellowing virus

    PubMed Central

    Nuruzzaman, Mohammed; Sharoni, Akhter M.; Satoh, Kouji; Karim, Mohammad Rezaul; Harikrishna, Jennifer A.; Shimizu, Takumi; Sasaya, Takahide; Omura, Toshihiro; Haque, Mohammad A.; Hasan, Sayed M. Z.; Ahmad, Aziz; Kikuchi, Shoshi

    2015-01-01

    Expression levels of the NAC gene family were studied in rice infected with Rice dwarf virus (RDV), Rice black-streaked dwarf virus (RBSDV), Rice grassy stunt virus (RGSV), Rice ragged stunt virus (RRSV), and Rice transitory yellowing virus (RTYV). Microarray analysis showed that 75 (68%) OsNAC genes were differentially regulated during infection with RDV, RBSDV, RGSV, and RRSV compared with the control. The number of OsNAC genes up-regulated was highest during RGSV infection, while the lowest number was found during RTYV infection. These phenomena correlate with the severity of the syndromes induced by the virus infections. Most of the genes in the NAC subgroups NAC22, SND, ONAC2, ANAC34, and ONAC3 were down-regulated for all virus infections. These OsNAC genes might be related to the health stage maintenance of the host plants. Interestingly, most of the genes in the subgroups TIP and SNAC were more highly expressed during RBSDV and RGSV infections. These results suggested that OsNAC genes might be related to the responses induced by the virus infection. All of the genes assigned to the TIP subgroups were highly expressed during RGSV infection when compared with the control. For RDV infection, the number of activated genes was greatest during infection with the S-strain, followed by the D84-strain and the O-strain, with seven OsNAC genes up-regulated during infection by all three strains. The Os12g03050 and Os11g05614 genes showed higher expression during infection with four of the five viruses, and Os11g03310, Os11g03370, and Os07g37920 genes showed high expression during at least three viral infections. We identified some duplicate genes that are classified as neofunctional and subfunctional according to their expression levels in different viral infections. A number of putative cis-elements were identified, which may help to clarify the function of these key genes in network pathways. PMID:26442000

  13. Deep Sequencing–Based Transcriptome Profiling Reveals Comprehensive Insights into the Responses of Nicotiana benthamiana to Beet necrotic yellow vein virus Infections Containing or Lacking RNA4

    PubMed Central

    Fan, Huiyan; Sun, Haiwen; Wang, Ying; Zhang, Yongliang; Wang, Xianbing; Li, Dawei; Yu, Jialin; Han, Chenggui

    2014-01-01

    Background Beet necrotic yellow vein virus (BNYVV), encodes either four or five plus-sense single stranded RNAs and is the causal agent of sugar beet rhizomania disease, which is widely distributed in most regions of the world. BNYVV can also infect Nicotiana benthamiana systemically, and causes severe curling and stunting symptoms in the presence of RNA4 or mild symptoms in the absence of RNA4. Results Confocal laser scanning microscopy (CLSM) analyses showed that the RNA4-encoded p31 protein fused to the red fluorescent protein (RFP) accumulated mainly in the nuclei of N. benthamiana epidermal cells. This suggested that severe RNA4-induced symptoms might result from p31-dependent modifications of the transcriptome. Therefore, we used next-generation sequencing technologies to analyze the transcriptome profile of N. benthamiana in response to infection with different isolates of BNYVV. Comparisons of the transcriptomes of mock, BN3 (RNAs 1+2+3), and BN34 (RNAs 1+2+3+4) infected plants identified 3,016 differentially expressed transcripts, which provided a list of candidate genes that potentially are elicited in response to virus infection. Our data indicate that modifications in the expression of genes involved in RNA silencing, ubiquitin-proteasome pathway, cellulose synthesis, and metabolism of the plant hormone gibberellin may contribute to the severe symptoms induced by RNA4 from BNYVV. Conclusions These results expand our understanding of the genetic architecture of N. benthamiana as well as provide valuable clues to identify genes potentially involved in resistance to BNYVV infection. Our global survey of gene expression changes in infected plants reveals new insights into the complicated molecular mechanisms underlying symptom development, and aids research into new strategies to protect crops against viruses. PMID:24416380

  14. Safflor yellow B suppresses angiotensin II-mediated human umbilical vein cell injury via regulation of Bcl-2/p22{sup phox} expression

    SciTech Connect

    Wang, Chaoyun; He, Yanhao; Yang, Ming; Sun, Hongliu; Zhang, Shuping; Wang, Chunhua

    2013-11-15

    Intracellular reactive oxygen species (ROS) are derived from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Angiotensin II (Ang II) can cause endothelial dysfunction by promoting intracellular ROS generation. Safflor yellow B (SYB) effectively inhibits ROS generation by upregulating Bcl-2 expression. In this study, we examined the effects of SYB on Ang II-induced injury to human umbilical vein endothelial cells (HUVECs), and elucidated the roles of NADPH oxidase and Bcl-2. We treated cultured HUVECs with Ang II, SYB, and Bcl-2 siRNA, and determined NADPH oxidase activity and ROS levels. Furthermore, cellular and mitochondrial physiological states were evaluated, and the expression levels of target proteins were analyzed. Ang II significantly enhanced intracellular ROS levels, caused mitochondrial membrane dysfunction, and decreased cell viability, leading to apoptosis. This was associated with increased expression of AT1R and p22{sup phox}, increased NADPH oxidase activity, and an increased ratio of Bax/Bcl-2, leading to decreases in antioxidant enzyme activities, which were further strengthened after blocking Bcl-2. Compared to Ang II treatment alone, co-treatment with SYB significantly reversed HUVEC injury. Taken together, these results demonstrate that SYB could significantly protect endothelial cells from Ang II-induced cell damage, and that it does so by upregulating Bcl-2 expression and inhibiting ROS generation. - Highlights: • Angiotensin II depresses mitochondria physiological function. • Angiotensin II activates NADPH oxidase via up-regulating expresion of p22{sup phox}. • Bcl-2 plays a pivotal role in improving mitochondria function and regulates ROS level. • Inhibitor of Bcl-2 promotes angiotensin II mediated HUVEC injury. • SYB attenuates angiotensin II mediated HUVEC injury via up regulating Bcl-2 expression.

  15. Lycus Sulci Slope Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    21 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark slope streaks on ridges in the Lycus Sulci region, north of the Olympus Mons volcano. Slope streaks form in the dry, dust-mantled regions of Mars. The darker streaks formed more recently than lighter ones, perhaps within the past Mars year or two. These streaks are located near 24.1oN, 146.1oW. This picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

  16. Quantitative and qualitative involvement of P3N-PIPO in overcoming recessive resistance against Clover yellow vein virus in pea carrying the cyv1 gene.

    PubMed

    Choi, Sun Hee; Hagiwara-Komoda, Yuka; Nakahara, Kenji S; Atsumi, Go; Shimada, Ryoko; Hisa, Yusuke; Naito, Satoshi; Uyeda, Ichiro

    2013-07-01

    In pea carrying cyv1, a recessive gene for resistance to Clover yellow vein virus (ClYVV), ClYVV isolate Cl-no30 was restricted to the initially infected cells, whereas isolate 90-1 Br2 overcame this resistance. We mapped the region responsible for breaking of cyv1-mediated resistance by examining infection of cyv1 pea with chimeric viruses constructed from parts of Cl-no30 and 90-1 Br2. The breaking of resistance was attributed to the P3 cistron, which is known to produce two proteins: P3, from the main open reading frame (ORF), and P3N-PIPO, which has the N-terminal part of P3 fused to amino acids encoded by a small open reading frame (ORF) called PIPO in the +2 reading frame. We introduced point mutations that were synonymous with respect to the P3 protein but nonsynonymous with respect to the P3N-PIPO protein, and vice versa, into the chimeric viruses. Infection of plants with these mutant viruses revealed that both P3 and P3N-PIPO were involved in overcoming cyv1-mediated resistance. Moreover, P3N-PIPO quantitatively affected the virulence of Cl-no30 in cyv1 pea. Additional expression in trans of the P3N-PIPO derived from Cl-no30, using White clover mosaic virus as a vector, enabled Cl-no30 to move to systemic leaves in cyv1 pea. Susceptible pea plants infected with chimeric ClYVV possessing the P3 cistron of 90-1 Br2, and which were therefore virulent toward cyv1 pea, accumulated more P3N-PIPO than did those infected with Cl-no30, suggesting that the higher level of P3N-PIPO in infected cells contributed to the breaking of resistance by 90-1 Br2. This is the first report showing that P3N-PIPO is a virulence determinant in plants resistant to a potyvirus. PMID:23616656

  17. Multiplex Reverse Transcription-PCR for Simultaneous Detection of Beet Necrotic Yellow Vein Virus, Beet Soilborne Virus, and Beet Virus Q and Their Vector Polymyxa betae KESKIN on Sugar Beet

    PubMed Central

    Meunier, Alexandre; Schmit, Jean-Franois; Stas, Arnaud; Kutluk, Nazli; Bragard, Claude

    2003-01-01

    Three soilborne viruses transmitted by Polymyxa betae KESKIN in sugar beet have been described: Beet necrotic yellow vein virus (BNYVV), the agent of rhizomania, Beet soilborne virus (BSBV), and Beet virus Q (BVQ). A multiplex reverse transcription-PCR technique was developed to simultaneously detect BNYVV, BSBV, and BVQ, together with their vector, P. betae. The detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. Systematic association of BNYVV with one or two different pomoviruses was observed. BVQ was detected in samples from Belgium, Bulgaria, France, Germany, Hungary, Italy, Sweden, and The Netherlands but not in samples from Turkey. PMID:12676720

  18. Microchannel plate streak camera

    DOEpatents

    Wang, C.L.

    1989-03-21

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras is disclosed. The improved streak camera is far more sensitive to photons (UV to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1,000 KeV x-rays. 3 figs.

  19. Microchannel plate streak camera

    DOEpatents

    Wang, Ching L. (Livermore, CA)

    1989-01-01

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras. The improved streak camera is far more sensitive to photons (UV to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1000 KeV x-rays.

  20. Microchannel plate streak camera

    DOEpatents

    Wang, C.L.

    1984-09-28

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras. The improved streak camera is far more sensitive to photons (uv to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1000 keV x-rays.

  1. Varicose Veins

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    ... Previous Section Next Section How Do Varicose Veins Impact My Health? Varicose veins can be cosmetically distressing ... What Causes Varicose Veins? How Do Varicose Veins Impact My Health? How Are Varicose Veins Diagnosed? How ...

  2. Crater and Wind Streak

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-461, 23 August 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater with a bright wind streak in southern Acidalia Planitia. The streak is mostly likely a very thin coating of dust. The orientation of the streak indicates that the winds responsible for its formation and maintenance came from the northeast (upper right) and blew toward the lower left (southwest). The crater is located near 24.8oN, 39.1oW. The image covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  3. Crater with Streak

    NASA Technical Reports Server (NTRS)

    2005-01-01

    20 June 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater in the Memnonia region of Mars, around which has formed a wind streak. The bright streak is in the lee of the crater -- that is, it is on the crater's down-wind side. Thus, the winds responsible for the streak blew from the southeast (lower right).

    Location near: 6.7oS, 141.4oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  4. Complex Wind Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    16 February 2004 Northeastern Tharsis is known for its complicated patterns of wind streaks. Wind streaks are formed by sediment transport and deposition by wind. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a pattern of crisscrossing streaks indicating winds that generally blow from the southwest (lower left) toward northeast (upper right), but vary over time. The image is located near 27.6oN, 98.9oW. Sunlight illuminates the scene from the lower left; the image covers an area 3 km (1.9 mi) wide.

  5. Arabian Slope Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-508, 9 October 2003

    Arabia Terra is a vast, heavily cratered region in the martian northern hemisphere. Much of Arabia Terra is thickly blanketed by dust. From time to time, on steep slopes, the dust will avalanche or slide downhill, creating a streak. The majority of slope streaks are darker than their surroundings, but not all of them are dark. In Arabia, it is common to find bright and dark slope streaks, and to find them together. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example, taken from a crater near 10.5oN, 318.4oW. Why some streaks are bright and others are dark is not yet known. This picture covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the left.

  6. Dark Slope Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    13 March 2004 Martian slope streaks occur in the regions most heavily mantled by fine, dry dust, particularly Tharsis, Arabia, and the knobby areas between Amazonis and Cerberus. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some examples of dark slope streaks off of buttes, mesas, and massifs in a dust-mantled crater in central Arabia Terra. New slope streaks form from time to time in the modern martian environment; the streaks in this image probably formed within the past decade. To create them, dust slid or avalanched down the slopes in an almost liquid-like manner. The image is located near 6.8oN, 321.7oW. The picture covers an area 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

  7. Wind Streak Changes

    NASA Technical Reports Server (NTRS)

    2004-01-01

    2 September 2004 This pair of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images shows changes in dark wind streak patterns that occurred between 5 April 1999 (image M00-00534) and 17 August 2004 (image R20-00901). Unlike the spaghetti-like streak patterns made by dust devils, these streaks all begin on their upwind ends as tapered forms that fan outward in the downwind direction, and they all indicate winds that blew from the same direction. In both cases, winds blew from the southeast (lower right) toward the northwest (upper left). These streaks and the small pedestal craters found among them occur in the Memnonia region of Mars near 5.9oS, 162.2oW. The 400 meter scale bar is about 437 yards long. Sunlight illuminates each scene from the upper left.

  8. Daedalia Wind Streak

    NASA Technical Reports Server (NTRS)

    2004-01-01

    21 January 2004 This January 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark wind streak in the lee of a small meteor impact crater in Daedalia Planum. The dominant winds responsible for this streak blew from the east (right). This picture is located near 17.1oS, 138.8oW, and covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

  9. Wind Streak and Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    23 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a wind streak developed in the lee of a meteor impact crater in western Daedalia Planum. The dominant winds responsible for the streak blew from the bottom/lower right (southeast). The image is located near 9.9oS, 144.9oW. Sunlight illuminates the scene from the lower left; the picture covers an area 3 km (1.9 mi) wide.

  10. Schiaparelli's Wind Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    9 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows craters and dark wind streaks on a plain on the floor of northeastern Schiaparelli Basin. The streaks indicate that dominant winds blow from the northeast (upper right). The image is located near 1.5oS, 339.8oW. Sunlight illuminates the scene from the lower left; the image covers an area 3 km (1.9 mi) wide.

  11. 'Dust' streaks on Mars

    NASA Astrophysics Data System (ADS)

    Thomas, P.; Veverka, J.; Gineris, D.; Wong, L.

    1984-10-01

    Global mapping and photometry of selected areas on Mars are used to investigate the nature of bright and dark wind streaks that extend from topographic obstacles. Occurrence of both bright and dark streaks is strongly latitude dependent and is only weakly correlated with surface properties such as albedo and thermal inertia. Data on the colors, albedos, and phase behavior of streaks are consistent with models of bright streaks as mosaics of plains materials and brighter, redder dust. Less than 20 percent of the ground need be covered by the optically thick dust in the brightest parts of the streaks; the amount of dust in optically thick layers could be as little as 0.001 g/sq cm. Dark streaks can be interpreted as erosional windows in a patchy dust cover. The model of dust deposition in optically thick patches is sedimentologically different from scenarios involving the deposition of ubiquitous, optically thin layers. It has the advantage that large amounts of dust can be deposited without affecting regional albedos.

  12. Frosty Wind Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-532, 2 November 2003

    As seasonal polar frosts sublime away each spring, winds may re-distribute some of the frost or move sediment exposed from beneath the frost. This action creates ephemeral wind streaks that can be used by scientists seeking to study the local circulation of the martian [missing text] surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of wind streaks created in subliming carbon dioxide frost. These dark streaks appear to conform to the shape of the slopes on which they occur, suggesting that slope winds play a dominant role in creating and orienting these streaks. This picture is located near 73.8oS, 305.7oW. The image is illuminated by sunlight from the upper left and covers an area 3 km (1.9 mi) wide. Winds responsible for the streaks generally blew from the bottom/right (south/southeast) toward the top/upper left (north/northwest).

  13. Lycus Sulci Slope Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    21 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark slope streaks coming off of rugged hills in the Lycus Sulci region, north of the Olympus Mons volcano. These slopes are mantled with fine, bright dust. From time to time, the dust will avalanche down a slope, forming a slope streak. The behavior of this dry, granular material can be somewhat fluid-like. New slope streaks can form at any time and, for an area the size of that shown here, may form at a rate of one per Mars year (687 Earth days). Naturally, some scientists have suggested that water plays a role in forming these streaks, but, in general, Mars is drier than the driest deserts on Earth and these streaks are contemporary features that occur in the dustiest regions of the planet. The image is located near 29.8oN, 133.4oW, and covers an area about 3 km (1.9 mi) across. The picture is illuminated by sunlight from the lower left.

  14. First Report of "Candidatus Liberibacter psyllaurous" (synonym "Ca. L. solanacearum") Associated with 'Tomato Vein-Greening' and 'Tomato psyllid yellows' Diseases in Commercial Greenhouses in Arizona

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During 2006-2007, tomato plants in two independent, commercial greenhouses in Arizona were infested with potato psyllid Paratrioza cockerelli. Over 60% and ~20% of plants in GH-1 and GH-2, respectively, exhibited leaf curling, stunting, and shortened internodes, and GH-1 plants also showed vein-gree...

  15. Polar Dust Devil Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    30 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image of dunes in the martian north polar region is important because it shows one of the highest northern latitude views of streaks thought to be made by passing dust devils. The dark, thin, filamentary streaks on the dunes and on the adjacent plains were probably formed by dust devils. The dunes occur near 76.6oN, 62.7oW. Dust devil streaks are observed on Mars at very high latitudes, such as this, all the way down to the equator. They are also seen at all elevations, from the deepest parts of the Hellas Basin to the summit of Olympus Mons. This picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  16. Tharsis Wind Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-533, 3 November 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows dark wind streaks on a plain east of Olympus Mons in the Tharsis region of Mars. Streaks such as these change from time to time over the course of a martian year, suggesting that they are the result of wind movement of a thin layer of bright dust. In other words, wind is not moving dark material to make the dark streaks, it is removing bright material (thin coatings of dust). This picture is located near 16.3oN, 127.7oW. The image covers an area 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

  17. Elysium Mons Wind Streak

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-556, 26 November 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a wind streak formed behind a meteor impact crater on the lower north flank of the volcano, Elysium Mons. Winds blow down the volcano slope, toward the northeast (toward upper right), causing a tail of uneroded dust to be captured behind the crater. Thin, filamentary dark streaks (resembling pencil scratches in this image) can be seen on the surface of the bright wind streak; these may have formed by disruption of surface dust by passing dust devils. This picture is located near 27.7oN, 212.7oW. The image covers an area 3 km (1.9 mi) wide, and is illuminated by sunlight from the left.

  18. Huygens Wind Streak

    NASA Technical Reports Server (NTRS)

    2005-01-01

    19 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of wind action on the floor of the giant martian impact basin, Huygens. The large crater in this image has a wind streak on its lee side, pointing toward the lower right (southeast). Usually, a light-toned wind streak behind a crater on Mars will be composed of a thin veneer of dust that the wind was not able to erode because it was protected by the presence of the crater's raised rims. In this case, the streak is caused by something different -- by the fact that dark, windblown sand has not been able to accumulate behind the crater.

    Location near: 13.0oS, 303.7oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

  19. The first 17 amino acids of the beet necrotic yellow vein virus RNA-5-encoded p26 protein are sufficient to activate transcription in a yeast one-hybrid system.

    PubMed

    Covelli, Laura; Klein, Elodie; Gilmer, David

    2009-01-01

    The beet necrotic yellow vein virus (BNYVV) RNA-5-encoded p26 protein is involved in the accentuation of symptoms expression of infected Chenopodium quinoa plants and is capable of transcription activation (TA) in yeast. TA was previously localized within the first 55 residues of the p26 protein. Interestingly, TA did not occur when C-terminally deleted forms of p26 were used. We used a genetic screen in the yeast one-hybrid system to select restored TA from randomly generated mutants. The TA domain was found to be located within the first 17 residues. Alanine replacement of aspartic acids 11, 16, and 17 within the full-length p26 prevented TA but did not impair subcellular localization and the symptom expression. PMID:19137435

  20. Interactive separating streak surfaces.

    PubMed

    Ferstl, Florian; Bürger, Kai; Theisel, Holger; Westermann, Rüdiger

    2010-01-01

    Streak surfaces are among the most important features to support 3D unsteady flow exploration, but they are also among the computationally most demanding. Furthermore, to enable a feature driven analysis of the flow, one is mainly interested in streak surfaces that show separation profiles and thus detect unstable manifolds in the flow. The computation of such separation surfaces requires to place seeding structures at the separation locations and to let the structures move correspondingly to these locations in the unsteady flow. Since only little knowledge exists about the time evolution of separating streak surfaces, at this time, an automated exploration of 3D unsteady flows using such surfaces is not feasible. Therefore, in this paper we present an interactive approach for the visual analysis of separating streak surfaces. Our method draws upon recent work on the extraction of Lagrangian coherent structures (LCS) and the real-time visualization of streak surfaces on the GPU. We propose an interactive technique for computing ridges in the finite time Lyapunov exponent (FTLE) field at each time step, and we use these ridges as seeding structures to track streak surfaces in the time-varying flow. By showing separation surfaces in combination with particle trajectories, and by letting the user interactively change seeding parameters such as particle density and position, visually guided exploration of separation profiles in 3D is provided. To the best of our knowledge, this is the first time that the reconstruction and display of semantic separable surfaces in 3D unsteady flows can be performed interactively, giving rise to new possibilities for gaining insight into complex flow phenomena. PMID:20975199

  1. Wind Streaks Among Flows

    NASA Technical Reports Server (NTRS)

    2004-01-01

    17 December 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark wind streaks formed by removal of a thin veneer of bright dust covering small craters and lava flow surfacesnorthwest of Olympus Mons near 28.4oN, 129.8oW. Streak orientations indicate that the responsible winds blew from the east/southeast (right/lower right) toward the west/northwest (left/upper left). The image covers an area about 3 km (1.9 mi) wide. Sunlight illuminates thescene from the lower left.

  2. Craters and Wind Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    25 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of small wind tails or streaks in the lees of impact craters in northeastern Tharsis near 25.8oN, 89.0oW. The streak tails point toward the east/northeast (right), indicating that the dominant winds blow from the west/southwest (left). This February 2004 picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

  3. Pavonis Wind Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-512, 13 October 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows wind tails and streaks formed in fine sediment that mantles the upper southwest slopes of the equatorial volcano, Pavonis Mons. On the large martian volcanoes, winds tend to blow downslope. The streaks shown here are evidence of the powerful ability for the thin atmosphere over the martian volcanoes to transport sediment. This picture is located near 0.1oN, 113.8oW, and covers an area 3 km (1.9 mi) wide. The image is illuminated by sunlight from the lower left.

  4. Daedalia Planum Wind Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-459, 21 August 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle (red camera) image shows streaks in the lee of obstacles such as meteor impact craters and lava flow margins in southwestern Daedalia Planum. The image covers an area about 252 km (157 mi) across near 13oS, 142oW. The streaks indicate that the dominant winds blow toward the northwest (left/upper left). Sunlight illuminates the scene from the left/upper left.

  5. Crater with Wind Streak

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-401, 24 June 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a streak formed by wind in the lee of a meteor impact crater. The winds responsible for the streak and the numerous smaller 'tails' behind small obstacles all indicate that regional winds blow from the right/upper right (northeast) toward the left/lower left (southwest). The crater is located near 13.7oS, 131.5oW. Sunlight illuminates the scene from the left/upper left.

  6. Layers and Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    6 December 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an outcrop of light-toned layered rock and a plethora of dark streaks on the floor of a crater in southern Noachis Terra. The streaks were created by dozens of dust devils which disrupted and perhaps removed some of the thin layer of dust that coats the surface. This view is located near 55.5oS, 333.4oW. The scene is illuminated by sunlight from the lower right. The 500 meter scale bar is approximately 547 yards long.

  7. Streak camera receiver definition study

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Hunkler, L. T., Sr.; Letzring, S. A.; Jaanimagi, P.

    1990-01-01

    Detailed streak camera definition studies were made as a first step toward full flight qualification of a dual channel picosecond resolution streak camera receiver for the Geoscience Laser Altimeter and Ranging System (GLRS). The streak camera receiver requirements are discussed as they pertain specifically to the GLRS system, and estimates of the characteristics of the streak camera are given, based upon existing and near-term technological capabilities. Important problem areas are highlighted, and possible corresponding solutions are discussed.

  8. MAIZE FINE STREAK VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The report outlines the salient features of maize fine streak virus (MFSV) including a general description of the causal virus species, virion properties, genome description, the relationship of the virus to other taxa, biological properties of the disease and agronomic aspects of the disease. Maize...

  9. Dark Slope Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-457, 19 August 2003

    This June 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater rim mantled with fine dust near 7.6oN, 171.8oW. Occasional avalanches of dust have created dark streaks that are tapered at their source and broaden downslope. A suite of particularly large streaks are seen in the lower right quarter of the picture. The MOC narrow angle camera does not take color images; this full-resolution (1.5 m/pixel; 5 ft/pixel) picture has been 'colorized' using data from a previous color image of Mars. Sunlight illuminates this scene from the lower left.

  10. Craters and Streaks

    NASA Technical Reports Server (NTRS)

    2006-01-01

    1 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two impact craters of nearly equal size, plus their associated wind streaks. These occur in far eastern Chryse Planitia. The wind streaks point toward the southwest (lower left), indicating that the responsible winds blew from the northeast. One of the two craters is shallower than the other, and has a suite of large, windblown ripples on its floor. The shallower crater with the ripples is probably older than the other, deeper crater.

    Location near: 20.6oN, 30.1oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  11. Slope Streaks in Arabia

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-353, 7 May 2003

    Light-, dark-, and intermediate-toned slope streaks are common in the thick, dust-mantled regions of Arabia Terra, parts of Tharsis, Memnonia, and some of the knobby areas west of Amazonis Planitia. They most likely form by avalanching of loose, dry dust, perhaps each triggered by a gust of wind. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired earlier this week (in May 2003), shows a plethora of slope streaks on the walls of an impact crater in east-central Arabia Terra near 13.0oN, 319.8oW. The image is 3 km (1.9 mi) wide; sunlight illuminates the scene from the left/lower left.

  12. Wind Streak in Daedalia

    NASA Technical Reports Server (NTRS)

    2005-01-01

    20 October 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a wind streak formed in the lee of an impact crater in western Daedalia Planum.

    Location near: 12.7oS, 136.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

  13. Dust Devil Streaks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    27 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of dark streaks created by spring and summer dust devil activity in Argyre Planitia.

    Location near: 64.9oS, 8.3oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  14. Dunes and Wind Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    12 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows small, dark, north polar sand dunes and attendant wind streaks located near 76.7oN, 317.6oW. The dominant winds responsible for these features blow from the southwest (lower left). The image covers an area about 3 km (1.9 mi) across. The scene is illuminated by sunlight from the lower left.

  15. Dark Slope Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-412, 5 July 2003

    On the dry, desert planet, Mars, wind is not the only contemporary geologic process that modifies the surface. Gravity also has a role to play. In regions such as Amazonis, Tharsis, and Arabia, most surfaces are covered by mantles of very fine dust. From time to time, an avalanche occurs on a dust-covered slope. This process is happening today, because changes have been observed by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) over the course if its mission, which began in September 1997. This picture shows a variety of dark slope streaks, formed by avalanches of dust, on the walls of a crater in southwest Amazonis near 7.6oN, 171.8oW. The size and shape of each slope streak, including the wide feature near the upper right, is determined by the steepness and texture of the slope on which it occurs. New slope streaks in some regions have been observed to form over periods of less than a few months to a year. This picture was taken in June 2003, and is illuminated from the lower left. The image is 2.3 km (1.4 mi) wide.

  16. Streaking tremor in Cascadia

    NASA Astrophysics Data System (ADS)

    Vidale, J. E.; Ghosh, A.; Sweet, J. R.; Creager, K. C.; Wech, A.; Houston, H.

    2009-12-01

    Details of tremor deep in subduction zones is damnably difficult to glimpse because of the lack of crisp initial arrivals, low waveform coherence, uncertain focal mechanisms, and the probability of simultaneous activity across extended regions. Yet such details hold out the best hope to illuminate the unknown mechanisms underlying episodic tremor and slip. Attacking this problem with brute force, we pointed a small, very dense seismic array down at the migration path of a good-sized episodic tremor and slip (ETS) event. In detail, it was an 84-element, 1300-m-aperture temporary seismic array in northern Washington, and the migration path of the May 2008 ETS event was 30-40 km directly underneath. Our beamforming technique tracked the time, incident angle, and azimuth of tremor radiation in unprecedented detail. We located the tremor by assuming it occurs on the subduction interface, estimated relative tremor moment released by each detected tremor window, and mapped it on the interface [Ghosh et al., GRL, 2009]. Fortunately for our ability to image it, the tremor generally appears to emanate from small regions, and we were surprised by how steadily the regions migrated with time. For the first time in Cascadia, we found convergence-parallel transient streaks of tremor migrating at velocities of several tens of km/hr, with movement in both up- and down-dip directions. Similar patterns have been seen in Japan [Shelly, G3, 2007]. This is in contrast to the long-term along-strike marching of tremor at 10 km/day. These streaks tend to propagate steadily and often repeat the same track on the interface multiple times. They light up persistent moment patches on the interface by a combination of increased amplitude and longer residence time within the patches. The up- and down-dip migration dominates the 2 days of tremor most clearly imaged by our array. The tendency of the streaks to fill in bands is the subject of the presentation of Ghosh et al. here. The physical mechanism causing the streaks, however, is not entirely clear. We suggest surges of fluid released at the megathrust may transmit stress pulses that cause failure by reducing effective normal stress along linear corrugated weak features on the fault. Houston et al., here, will explore the implications of tremor streaks for a source model.

  17. Triton's streaks as windblown dust

    NASA Technical Reports Server (NTRS)

    Sagan, Carl; Chyba, Christopher

    1990-01-01

    Explanations for the surface streaks observed by Voyager 2 on Triton's southern hemisphere are discussed. It is shown that, despite Triton's tenuous atmosphere, low-cohesion dust trains with diameters of about 5 micron or less may be carried into suspension by aeolian surface shear stress, given expected geostrophic wind speeds of about 10 m/s. For geyser-like erupting dust plumes, it is shown that dust-settling time scales and expected wind velocities can produce streaks with length scales in good agreement with those of the streaks. Thus, both geyserlike eruptions or direct lifting by surface winds appear to be viable mechanisms for the origin of the streaks.

  18. Bright Streak on Amalthea

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These two images of Jupiter's small, irregularly shaped moon Amalthea, obtained by the camera onboard NASA's Galileo spacecraft in August 1999(left) and November 1999 (right), form a 'stereo pair' that helps scientists determine this moon's shape and the topography of its surface features. Features as small as 3.8 kilometers (2.4 miles) across can be resolved in these images, making them among the highest-resolution images ever taken of Amalthea.

    The large impact crater visible in both images, near the right-hand edge of Amalthea's disk, is about 40 kilometers (about 29 miles) across; two ridges, tall enough to cast shadows, extend from the top of the crater in a V-shape reminiscent of a 'rabbit ears' television antenna. To the left of these ridges, in the top center portion of Amalthea's disk, is a second large impact crater similar in size to the first crater. To the left of this second crater is a linear 'streak' of relatively bright material about 50 kilometers (31 miles) long. In previous spacecraft images of Amalthea taken from other viewing directions, this bright feature was thought to be a small, round, bright 'spot' and was given the name Ida. These new images reveal for the first time that Ida is actually a long, linear 'streak.' This bright streak may represent material ejected during the formation of the adjacent impact crater, or it may just mark the crest of a local ridge. Other patches of relatively bright material can be seen elsewhere on Amalthea's disk, although none of these other bright spots has Ida's linear shape.

    In both images, sunlight is coming from the left and north is approximately up. Note that the north pole of Amalthea is missing in the right-hand image (it was cut off by the edge of the camera frame). The bright streak, Ida, is on the side of the moon that faces permanently away from Jupiter, and the crater near the right-hand edge of the disk is in the center of Amalthea's leading side (the side of the moon that 'leads' as Amalthea moves in its orbit around Jupiter).

    The images are, from left to right: Amalthea taken on August 12, 1999 at a range of 446,000 kilometers (about 277,000 miles) and on November 26, 1999 at a range of 374,000 kilometers (about 232,000 miles).

  19. Daedalia Planum Wind Streak

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-332, 16 April 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a complex streak formed by deposition and erosion of sediment by wind in the lee of an impact crater in western Daedalia Planum. The winds needed to create this feature blew from the southeast (from the lower right). The picture covers an area 3 km (1.9 mi) wide near 10.1oS, 133.7oW. Sunlight illuminates the scene from the upper left.

  20. South Polar Wind Streak

    NASA Technical Reports Server (NTRS)

    2004-01-01

    19 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small meteor impact crater, about 90 meters (295 feet) in diameter, with a short, dark wind streak on its down-wind side. The crater is located atop south polar layered materials near 80.2oS, 210.4oW. The March 2004, early autumn picture covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

  1. Bright Devil Streaks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    4 March 2005 In honor of Giovanni V. Schiaparelli's 170th birthday, we present this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image showing light-toned dust devil streaks on the southern floor of Schiaparelli Crater.

    Location near: 5.3oS, 343.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

  2. Wind Streak Changes

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-358, 12 May 2003

    Mars is a dynamic planet. This pair of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) pictures, taken 2 Mars years apart, show changes in dark streak patterns caused by wind movement of dust. The top picture was taken in July 1999, the bottom one in March 2003. The pair of images are in Tharsis near 9.5oS, 128.5oW. Sunlight illuminates both from the upper left.

  3. Crater with Streak

    NASA Technical Reports Server (NTRS)

    2004-01-01

    6 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small meteor impact crater (approximately the size of the famous Meteor Crater in northern Arizona) with a bright wind streak on its west (left) side. Generally, winds blowing from the east (right) have stripped away bright dust everywhere but in the lee of the crater. These landforms are located in eastern Kasei Valles near 25.1oN, 60.8oW. The picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left/lower left.

  4. Streaks and Lava Flows

    NASA Technical Reports Server (NTRS)

    2004-01-01

    5 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows alternating light and dark wind streaks superimposed over a rugged lava flow surface on the west flank of the volcano, Ascraeus Mons. A chain of pits in the upper half of the image mark the location of a collapsed lava tube. The image is located near 11.6oN, 105.5oW, and covers an area about 3 km (1.9 mi) across. The scene is illuminated by sunlight from the lower left.

  5. Wind Streaks Near Schiaparelli

    NASA Technical Reports Server (NTRS)

    2004-01-01

    15 September 2004 Mars is a desert world. Today, wind is the most powerful agent of change. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows streak patterns made by wind as it distributed and re-distributed dark sediment across a light-toned substrate. This image is located west of Schiaparelli Crater near 1.0oS, 347.6oW, and covers an area approximately 3 km (1.9 mi) across. The scene is illuminated by sunlight from the left/upper left.

  6. Streaking into Middle School Science: The Dell Streak Pilot Project

    ERIC Educational Resources Information Center

    Austin, Susan Eudy

    2012-01-01

    A case study is conducted implementing the Dell Streak seven-inch android device into eighth grade science classes of one teacher in a rural middle school in the Piedmont region of North Carolina. The purpose of the study is to determine if the use of the Dell Streaks would increase student achievement on standardized subject testing, if the

  7. Streaking into Middle School Science: The Dell Streak Pilot Project

    ERIC Educational Resources Information Center

    Austin, Susan Eudy

    2012-01-01

    A case study is conducted implementing the Dell Streak seven-inch android device into eighth grade science classes of one teacher in a rural middle school in the Piedmont region of North Carolina. The purpose of the study is to determine if the use of the Dell Streaks would increase student achievement on standardized subject testing, if the…

  8. Varicose Veins

    MedlinePLUS

    ... the valves are weak or damaged, blood can back up and pool in your veins. This causes ... pregnancy. Doctors often diagnose varicose veins from a physical exam. ... to remove them. NIH: National Heart, Lung, and Blood Institute

  9. Light and Dark Slope Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    21 July 2004 Dark slope streaks are a common feature on slopes thickly-mantled by dust, especially in the Tharsis, Arabia, and western Amazonis regions of Mars. Less common are light-toned slope streaks, which often occur in the same area as dark streaks. They are most common in Arabia Terra, and some are shown in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. Slope streaks are probably the result of sudden avalanches of extremely dry dust. The behavior of the avalanching dust is somewhat fluid-like, and new streaks have been observed to form over intervals of a few months to a Mars year. This image is located near 13.4oN, 340.3oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  10. Cerberus Wind Streaks

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 6 May 2002) The Science Cerberus is a dark region on Mars that has shrunk down from a continuous length of about 1000 km to roughly three discontinuous spots a few 100 kms in length in less than 20 years. There are two competing processes at work in the Cerberus region that produce the bright and dark features seen in this THEMIS image. Bright dust settles out of the atmosphere, especially after global dust storms, depositing a layer just thick enough to brighten the dark surfaces. Deposition occurs preferentially in the low wind 'shadow zones' within craters and downwind of crater rims, producing the bright streaks. The direction of the streaks clearly indicates that the dominant winds come from the northeast. Dust deposition would completely blot out the dark areas if it were not for the action of wind-blown sand grains scouring the surface and lifting the dust back into the atmosphere. Again, the shadow zones are protected from the blowing sand, preserving the bright layer of dust. Also visible in this image are lava flow features extending from the flanks of the huge Elysium volcanoes to the northwest. Two shallow channels and a raised flow lobe are just barely discernable. The lava channel in the middle of the image crosses the boundary of the bright and dark surfaces without any obvious change in its morphology. This demonstrates that the bright dust layer is very thin in this location, perhaps as little as a few millimeters. The Story Mars is an ever-changing land of spectacular contrasts. This THEMIS image shows the Cerberus region of Mars, a dark area located near the Elysium volcanoes and fittingly named after the three-headed, dragon-tailed dog who guards the door of the underworld. Two opposing processes are at work here: a thin layer of dust falling from the atmosphere and/or dust storms creating brighter surface areas (e.g. the top left portion of this image) and dust being scoured away by the action of the Martian wind disturbing the sand grains and freeing the lighter dust to fly away once more (the darker portions of this image). There are, however, some darker areas that are somewhat shielded and protected from the wind that have yielded bright, dusty crater floors and wind streaks that trail out behind the craters. These wind streaks tell a story all their own as to the prevailing wind direction coming from the northeast. This, added to the fact that this dark region was once 1000 km in length and has dwindled to just a few isolated dark splotches of 100 kilometers in the past 20 years, help us to see that the Martian environment is still quite dynamic and capable of changing. Finally, this being a volcanic region, a lobe of a lava flow from the immense Elysium volcanoes to the northwest is visible stretching across the bottom one-quarter of the image.

  11. Streak camera time calibration procedures

    NASA Technical Reports Server (NTRS)

    Long, J.; Jackson, I.

    1978-01-01

    Time calibration procedures for streak cameras utilizing a modulated laser beam are described. The time calibration determines a writing rate accuracy of 0.15% with a rotating mirror camera and 0.3% with an image converter camera.

  12. Yellow Fever

    MedlinePLUS

    ... Search The CDC Cancel Submit Search The CDC Yellow Fever Note: Javascript is disabled or is not supported ... CDC.gov . Recommend on Facebook Tweet Share Compartir Yellow fever virus is found in tropical and subtropical areas ...

  13. YELLOW BERRY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow berry refers to the non-vitreous form of the wheat kernel. Individual kernels may be vitreous, non-vitreous (yellow berry) or have varying proportions of each (mottled). Yellow berry, in and of itself, represents no defect of the kernel. As in maize, rice and other cereals, the non-vitre...

  14. The use of latent class analysis to estimate the sensitivities and specificities of diagnostic tests for Squash vein yellowing virus in cucurbit species when there is no gold standard.

    PubMed

    Turechek, William W; Webster, Craig G; Duan, Jingyi; Roberts, Pamela D; Kousik, Chandrasekar S; Adkins, Scott

    2013-12-01

    Squash vein yellowing virus (SqVYV) is the causal agent of viral watermelon vine decline, one of the most serious diseases in watermelon (Citrullus lanatus L.) production in the southeastern United States. At present, there is not a gold standard diagnostic test for determining the true status of SqVYV infection in plants. Current diagnostic methods for identification of SqVYV-infected plants or tissues are based on the reverse-transcription polymerase chain reaction (RT-PCR), tissue blot nucleic acid hybridization assays (TB), and expression of visual symptoms. A quantitative assessment of the performance of these diagnostic tests is lacking, which may lead to an incorrect interpretation of results. In this study, latent class analysis (LCA) was used to estimate the sensitivities and specificities of RT-PCR, TB, and visual assessment of symptoms as diagnostic tests for SqVYV. The LCA model assumes that the observed diagnostic test responses are linked to an underlying latent (nonobserved) disease status of the population, and can be used to estimate sensitivity and specificity of the individual tests, as well as to derive an estimate of the incidence of disease when a gold standard test does not exist. LCA can also be expanded to evaluate the effect of factors and was done here to determine whether diagnostic test performances varied among the type of plant tissue being tested (crown versus vine tissue), where plant samples were taken relative to the position of the crown (i.e., distance from the crown), host (i.e., genus), and habitat (field-grown versus greenhouse-grown plants). Results showed that RT-PCR had the highest sensitivity (0.94) and specificity (0.98) of the three tests. TB had better sensitivity than symptoms for detection of SqVYV infection (0.70 versus 0.32), while the visual assessment of symptoms was more specific than TB and, thus, a better indicator of noninfection (0.98 versus 0.65). With respect to the grouping variables, RT-PCR and TB had better sensitivity but poorer specificity for diagnosing SqVYV infection in crown tissue than it did in vine tissue, whereas symptoms had very poor sensitivity but excellent specificity in both tissues for all cucurbits analyzed in this study. Test performance also varied with habitat and genus but not with distance from the crown. The results given here provide quantitative measurements of test performance for a range of conditions and provide the information needed to interpret test results when tests are used in parallel or serial combination for a diagnosis. PMID:23883156

  15. Streak camera dynamic range optimization

    SciTech Connect

    Wiedwald, J.D.; Lerche, R.A.

    1987-09-01

    The LLNL optical streak camera is used by the Laser Fusion Program in a wide range of applications. Many of these applications require a large recorded dynamic range. Recent work has focused on maximizing the dynamic range of the streak camera recording system. For our streak cameras, image intensifier saturation limits the upper end of the dynamic range. We have developed procedures to set the image intensifier gain such that the system dynamic range is maximized. Specifically, the gain is set such that a single streak tube photoelectron is recorded with an exposure of about five times the recording system noise. This ensures detection of single photoelectrons, while not consuming intensifier or recording system dynamic range through excessive intensifier gain. The optimum intensifier gain has been determined for two types of film and for a lens-coupled CCD camera. We have determined that by recording the streak camera image with a CCD camera, the system is shot-noise limited up to the onset of image intensifier nonlinearity. When recording on film, the film determines the noise at high exposure levels. There is discussion of the effects of slit width and image intensifier saturation on dynamic range. 8 refs.

  16. Vein Problems Related to Varicose Veins

    MedlinePLUS

    ... lakes are varicose veins that appear on the face and neck. Reticular veins are flat blue veins often seen behind the knees. Hemorrhoids are varicose veins in and around the ... STATEMENT FOIA OIG CONTACT US National ...

  17. Circular Scan Streak Tube Development

    NASA Technical Reports Server (NTRS)

    Nevin, S.

    1980-01-01

    A streak tube having circular scan was designed, built and tested. Continuous circular scan, easily derived from out of phase sine waves applied to the conventional deflection plates, permits the timing of pulses traveling long baselines. At the tube's output a circular array of 720 elements is scanned to provide 30 to 40 picosecond resolution. Initial difficulties with electron bombarded silicon arrays were circumvented by using microchannel plates within the streak tube to provide the needed electronic amplification and digital sensitivity and coupling the 720 element arrays to the electron beam by means of a phosphor on a fiber optics. Two ceramic body tubes with S-20 photocathodes were tested and delivered.

  18. Varicose Veins

    MedlinePLUS

    ... heart pumps the blood to your lungs to pick up oxygen. The oxygen-rich blood then is pumped ... returns to your heart through your veins to pick up more oxygen. For more information about blood flow, ...

  19. Properties of martian slope streak populations

    NASA Astrophysics Data System (ADS)

    Bergonio, Justin R.; Rottas, Kimberly M.; Schorghofer, Norbert

    2013-07-01

    Slope streaks are down-slope mass movements on the surface of Mars that are among the few known examples of contemporary geologic activity on Mars. Here we study slope streak activity over three decades, based on overlapping images in the Lycus Sulci region taken by the Context Camera (CTX) 2007-2010 and the Viking Orbiter Camera in 1977. The number of disappeared slope streaks is nearly equal the number of newly formed slope streaks, suggesting the streak population is balanced. The turnover time of the population is estimated to be four decades. Slope streaks fade gradually over time, with islands of persistence. We also determine the number of observable slope streaks as a function of image resolution based on images by the High Resolution Imaging Science Experiment (HiRISE) camera, and find that the number of discernible slope streaks can increase rapidly with spatial resolution.

  20. Streaking into middle school science: The Dell Streak pilot project

    NASA Astrophysics Data System (ADS)

    Austin, Susan Eudy

    A case study is conducted implementing the Dell Streak seven-inch android device into eighth grade science classes of one teacher in a rural middle school in the Piedmont region of North Carolina. The purpose of the study is to determine if the use of the Dell Streaks would increase student achievement on standardized subject testing, if the Streak could be used as an effective instructional tool, and if it could be considered an effective instructional resource for reviewing and preparing for the science assessments. A mixed method research design was used for the study to analyze both quantitative and qualitative results to determine if the Dell Streaks' utilization could achieve the following: 1. instructional strategies would change, 2. it would be an effective instructional tool, and 3. a comparison of the students' test scores and benchmark assessments' scores would provide statistically significant difference. Through the use of an ANOVA it was determined a statistically significant difference had occurred. A Post Hoc analysis was conducted to identify where the difference occurred. Finally a T-test determined was there was no statistically significance difference between the mean End-of-Grade tests and four quarterly benchmark scores of the control and the experimental groups. Qualitative research methods were used to gather results to determine if the Streaks were an effective instructional tool. Classroom observations identified that the teacher's teaching styles and new instructional strategies were implemented throughout the pilot project. Students had an opportunity to complete a questionnaire three times during the pilot project. Results revealed what the students liked about using the devices and the challenges they were facing. The teacher completed a reflective questionnaire throughout the pilot project and offered valuable reflections about the use of the devices in an educational setting. The reflection data supporting the case study was drawn from the teacher's statements regarding the change in instructional delivery as a respect of using the students' device. The results section of the study will elaborate upon these findings. The study recommendations on the use of the Dell Streak device will address whether further actions as the use of the Streak technology in the classroom and summary section.

  1. Slope Streaks in Terra Sabaea

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Click on image for larger version

    This HiRISE image shows the rim of a crater in the region of Terra Sabaea in the northern hemisphere of Mars.

    The subimage (figure 1) is a close-up view of the crater rim revealing dark and light-toned slope streaks. Slope streak formation is among the few known processes currently active on Mars. While their mechanism of formation and triggering is debated, they are most commonly believed to form by downslope movement of extremely dry sand or very fine-grained dust in an almost fluidlike manner (analogous to a terrestrial snow avalanche) exposing darker underlying material.

    Other ideas include the triggering of slope streak formation by possible concentrations of near-surface ice or scouring of the surface by running water from aquifers intercepting slope faces, spring discharge (perhaps brines), and/or hydrothermal activity.

    Several of the slope streaks in the subimage, particularly the three longest darker streaks, show evidence that downslope movement is being diverted around obstacles such as large boulders. Several streaks also appear to originate at boulders or clumps of rocky material.

    In general, the slope streaks do not have large deposits of displaced material at their downslope ends and do not run out onto the crater floor suggesting that they have little reserve kinetic energy. The darkest slope streaks are youngest and can be seen to cross cut and superpose older and lighter-toned streaks. The lighter-toned streaks are believed to be dark streaks that have lightened with time as new dust is deposited on their surface.

    Observation Geometry Image PSP_001808_1875 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 15-Dec-2006. The complete image is centered at 7.4 degrees latitude, 47.0 degrees East longitude. The range to the target site was 272.1 km (170.1 miles). At this distance the image scale is 54.4 cm/pixel (with 2 x 2 binning) so objects 163 cm across are resolved. The image shown here has been map-projected to 50 cm/pixel and north is up. The image was taken at a local Mars time of 03:36 PM and the scene is illuminated from the west with a solar incidence angle of 53 degrees, thus the sun was about 37 degrees above the horizon. At a solar longitude of 150.7 degrees, the season on Mars is Northern Summer.

    NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.

  2. Yellow fever.

    PubMed

    Monath, Thomas P; Vasconcelos, Pedro F C

    2015-03-01

    Yellow fever, a mosquito-borne flavivirus disease occurs in tropical areas of South America and Africa. It is a disease of major historical importance, but remains a threat to travelers to and residents of endemic areas despite the availability of an effective vaccine for nearly 70 years. An important aspect is the receptivity of many non-endemic areas to introduction and spread of yellow fever. This paper reviews the clinical aspects, pathogenesis, and epidemiology of yellow fever, with an emphasis on recent changes in the distribution and incidence of the disease. Recent knowledge about yellow fever 17D vaccine mechanism of action and safety are discussed. PMID:25453327

  3. Wind Streaks on Daedalia Planum

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Daedalia Planum is a broad, wind-swept volcanic plain southwest of the Arsia Mons volcano. Since the 1972 Mariner 9 mission, this region has been known to have many wind streaks formed in the lee of obstacles (i.e., downwind of craters and hills) as wind blows loose sediment through the region. Here, the wind streaks are a combination of bright surfaces (where sand and/or dust has accumulated) and dark surfaces (where sand and/or dust has been removed). The streaks indicate wind blowing from right to left. Other evidence of wind action is found in the form of many parallel ridges and grooves that run diagonally across the scene--these probably formed by wind erosion at an earlier time when the wind was blowing from a direction different from that indicated by the bright and dark streaks. This picture was taken by the Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) and is illuminated from the left. The picture covers an area about 7.6 km (4.7 miles) by 9.3 km (5.8 miles).

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  4. Wind vs. Dust Devil Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    22 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image presents a fine illustration of the difference between streaks made by dust devils and streaks made by wind gusts. Dust devils are usually solitary, spinning vortices. They resemble a tornado, or the swirling motion of a familiar, Tasmanian cartoon character. Wind gusts, on the other hand, can cover a larger area and affect more terrain at the same time. The dark, straight, and parallel features resembling scrape marks near the right/center of this image are thought to have been formed by a singular gust of wind, whereas the more haphazard dark streaks that crisscross the scene were formed by dozens of individual dust devils, acting at different times. This southern summer image is located in Noachis Terra near 67.0oS, 316.2oW. Sunlight illuminates the scene from the upper left; the picture covers an area 3 km (1.9 mi) wide.

  5. Yellow fever

    MedlinePLUS

    ... the heart, liver, and kidney. Bleeding disorders, seizures, coma, and delirium may also occur. Symptoms may include: Irregular heartbeats (arrhythmias) Bleeding (may progress to hemorrhage) Coma Decreased urination Delirium Fever Headache Yellow skin and ...

  6. Dune and Dust Devil Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-474, 5 September 2003

    This August 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a dark sand dune on the floor of a crater at 54.9oS, 342.5oW. Recent dust devils have disrupted a thin coating of dust on the otherwise dark dune; these wind phenomena created the plethora of markings and streaks on the dune. The image covers an area 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

  7. Earth and planetary aeolian streaks: A review

    NASA Astrophysics Data System (ADS)

    Cohen-Zada, Aviv Lee; Blumberg, Dan Gabriel; Maman, Shimrit

    2016-03-01

    Wind streaks are abundant aeolian features that have been observed on planetary surfaces by remote sensing means. They have been widely studied, particularly on Mars and Venus and to a much lesser extent on Earth. In imagery, these streaks appear as elongated features that are easily distinguishable from their surroundings. Geomorphologically, these streaks have, thus far, been interpreted as the presence or absence of small loose particles on the surface, deposited or eroded, respectively, by wind. However, the use of different (optical and radar) remote-sensing tools to study wind streaks has led to uncertain interpretations of these features and has hindered their geomorphological definition. Since wind streaks indicate the prevailing wind direction at the time of their formation, they may be used to map near-surface winds and to estimate atmospheric circulation patterns. The aim of this article is to review the main studies focusing on wind streaks and to present the most up-to-date knowledge on this topic. Moreover, a new perspective for wind streak research is suggested: As 'wind streak' is a collective term for a variety of aeolian features that when viewed from above appear as distinctive albedo surface patterns, we suggest that the term should not be used to refer to a geomorphological feature. Since the definition of wind streaks is constrained to remote sensing rather than to geomorphology and is affected by the inherent biases of remote sensing methods, we suggest that 'wind streaks' should be used as a collective term for aeolian surfaces that are discernable from above as bright and dark patterns due to alterations in the characteristics of the surface or to the presence of bedforms. To better understand the mechanisms, time-frames, climate compatibility of wind streaks and the influences of remote sensing on their appearance, we have compiled a new database containing more than 2,900 Earth wind streaks. A comprehensive study of these Earth wind streaks will make far-reaching contributions not only to the understanding of wind streaks but also to Earth and planetary climate research.

  8. Wind Streaks on Earth; Exploration and Interpretation

    NASA Astrophysics Data System (ADS)

    Cohen-Zada, Aviv Lee; Blumberg, Dan G.; Maman, Shimrit

    2015-04-01

    Wind streaks, one of the most common aeolian features on planetary surfaces, are observable on the surface of the planets Earth, Mars and Venus. Due to their reflectance properties, wind streaks are distinguishable from their surroundings, and they have thus been widely studied by remote sensing since the early 1970s, particularly on Mars. In imagery, these streaks are interpreted as the presence - or lack thereof - of small loose particles on the surface deposited or eroded by wind. The existence of wind streaks serves as evidence for past or present active aeolian processes. Therefore, wind streaks are thought to represent integrative climate processes. As opposed to the comprehensive and global studies of wind streaks on Mars and Venus, wind streaks on Earth are understudied and poorly investigated, both geomorphologically and by remote sensing. The aim of this study is, thus, to fill the knowledge gap about the wind streaks on Earth by: generating a global map of Earth wind streaks from modern high-resolution remotely sensed imagery; incorporating the streaks in a geographic information system (GIS); and overlaying the GIS layers with boundary layer wind data from general circulation models (GCMs) and data from the ECMWF Reanalysis Interim project. The study defines wind streaks (and thereby distinguishes them from other aeolian features) based not only on their appearance in imagery but more importantly on their surface appearance. This effort is complemented by a focused field investigation to study wind streaks on the ground and from a variety of remotely sensed images (both optical and radar). In this way, we provide a better definition of the physical and geomorphic characteristics of wind streaks and acquire a deeper knowledge of terrestrial wind streaks as a means to better understand global and planetary climate and climate change. In a preliminary study, we detected and mapped over 2,900 wind streaks in the desert regions of Earth distributed in approximately 500 sites. Most terrestrial wind streaks are formed on a relatively young geological surface and are concentrated along the equator (± 30°). They are categorized by the combination of their planform and reflectance; with linear-bright and dark are the most common. A site-specific examination of remote-sensing effects on wind streaks identification has been conducted. The results thus far, indicate that in images with varying spatial and spectral specifications some wind streaks are actually composed of other aeolian bedforms, especially dunes. Specific regions of the Earth were then compared qualitatively to surface wind data extracted from a general circulation model. Understanding the mechanism and spatial and temporal distribution of wind streak formation is important not only for understanding surface modifications in the geomorphological context but also for shedding light on past and present climatic processes and atmospheric circulation on Earth. This study yields an explanation for wind streaks as a geomorphological feature. Moreover, it is in this planet-wide geomorphological research ability to lay down the foundations for comparative planetary research.

  9. Orbital objects detection algorithm using faint streaks

    NASA Astrophysics Data System (ADS)

    Tagawa, Makoto; Yanagisawa, Toshifumi; Kurosaki, Hirohisa; Oda, Hiroshi; Hanada, Toshiya

    2016-02-01

    This study proposes an algorithm to detect orbital objects that are small or moving at high apparent velocities from optical images by utilizing their faint streaks. In the conventional object-detection algorithm, a high signal-to-noise-ratio (e.g., 3 or more) is required, whereas in our proposed algorithm, the signals are summed along the streak direction to improve object-detection sensitivity. Lower signal-to-noise ratio objects were detected by applying the algorithm to a time series of images. The algorithm comprises the following steps: (1) image skewing, (2) image compression along the vertical axis, (3) detection and determination of streak position, (4) searching for object candidates using the time-series streak-position data, and (5) selecting the candidate with the best linearity and reliability. Our algorithm's ability to detect streaks with signals weaker than the background noise was confirmed using images from the Australia Remote Observatory.

  10. Deep Vein Thrombosis

    MedlinePLUS

    Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most deep vein clots occur in the lower leg or ... vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a ...

  11. Cell movement during chick primitive streak formation

    PubMed Central

    Chuai, Manli; Zeng, Wei; Yang, Xuesong; Boychenko, Veronika; Glazier, James A.; Weijer, Cornelis J.

    2008-01-01

    Gastrulation in amniotes begins with extensive re-arrangements of cells in the epiblast resulting in the formation of the primitive streak. We have developed a transfection method that enables us to transfect randomly distributed epiblast cells in the Stage XIXIII chick blastoderms with GFP fusion proteins. This allows us to use time-lapse microscopy for detailed analysis of the movements and proliferation of epiblast cells during streak formation. Cells in the posterior two thirds of the embryo move in two striking counter-rotating flows that meet at the site of streak formation at the posterior end of the embryo. Cells divide during this rotational movement with a cell cycle time of 67 h. Daughter cells remain together, forming small clusters and as result of the flow patterns line up in the streak. Expression of the cyclin-dependent kinase inhibitor, P21/Waf inhibits cell division and severely limits embryo growth, but does not inhibit streak formation or associated flows. To investigate the role off cellcell intercalation in streak formation we have inhibited the Wnt planar-polarity signalling pathway by expression of a dominant negative Wnt11 and a Dishevelled mutant Xdd1. Both treatments do not result in an inhibition of streak formation, but both severely affect extension of the embryo in later development. Likewise inhibition of myosin II which as been shown to drive cellcell intercalation during Drosophila germ band extension, has no effect on streak formation, but also effectively blocks elongation after regression has started. These experiments make it unlikely that streak formation involves known cellcell intercalation mechanisms. Expression of a dominant negative FGFR1c receptor construct as well as the soluble extracellular domain of the FGFR1c receptor both effectively block the cell movements associated with streak formation and mesoderm differentiation, showing the importance of FGF signalling in these processes. PMID:16725136

  12. What Causes Varicose Veins?

    MedlinePLUS

    ... Weak vein walls may cause weak valves. Normally, the walls of the veins are elastic (stretchy). If these ... become like an overstretched rubber band. This makes the walls of the veins longer and wider, and it ...

  13. Deep Vein Thrombosis

    MedlinePLUS

    ... page from the NHLBI on Twitter. What Is Deep Vein Thrombosis? Espaol Deep vein thrombosis (throm-BO-sis), or DVT, is a blood clot that forms in a vein deep in the body. Blood clots occur when blood ...

  14. Bright Streaks and Dark Fans

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The south polar region of Mars is covered every year by a layer of carbon dioxide ice. In a region called the 'cryptic terrain,' the ice is translucent and sunlight can penetrate through the ice to warm the surface below.

    The ice layer sublimates (evaporates) from the bottom. The dark fans of dust seen in this image come from the surface below the layer of ice, carried to the top by gas venting from below. The translucent ice is 'visible' by virtue of the effect it has on the tone of the surface below, which would otherwise have the same color and reflectivity as the fans.

    Bright streaks in this image are fresh frost. The CRISM team has identified the composition of these streaks to be carbon dioxide.

    Observation Geometry Image PSP_003113_0940 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 26-Mar-2007. The complete image is centered at -85.8 degrees latitude, 106.0 degrees East longitude. The range to the target site was 244.9 km (153.0 miles). At this distance the image scale is 49.0 cm/pixel (with 2 x 2 binning) so objects 147 cm across are resolved. The image shown here has been map-projected to 50 cm/pixel . The image was taken at a local Mars time of 06:20 PM and the scene is illuminated from the west with a solar incidence angle of 79 degrees, thus the sun was about 11 degrees above the horizon. At a solar longitude of 207.6 degrees, the season on Mars is Northern Autumn.

  15. Electro-optic Phase Grating Streak Spectrometer

    SciTech Connect

    Goldin, F. J.

    2012-08-02

    The electro-optic phase grating streak spectrometer (EOPGSS) generates a time-resolved spectra equivalent to that obtained with a conventional spectrometer/streak camera combination, but without using a streak camera (by far the more expensive and problematic component of the conventional system). The EOPGSS is based on a phase, rather than an amplitude grating. Further, this grating is fabricated of electro-optic material such as, for example, KD*P, by either etching grooves into an E-O slab, or by depositing lines of the E-O material onto an optical flat. An electric field normal to the grating alters the material’s index of refraction and thus affects a shift (in angle) of the output spectrum. Ramping the voltage streaks the spectrum correspondingly. The streak and dispersion directions are the same, so a second (static, conventional) grating disperses the spectrum in the orthogonal direction to prevent different wavelengths from “overwriting” each other. Because the streaking is done by the grating, the streaked output spectrum is recorded with a time-integrating device, such as a CCD. System model, typical design, and performance expectations will be presented.

  16. Atomic and molecular phases through attosecond streaking

    SciTech Connect

    Baggesen, Jan Conrad; Madsen, Lars Bojer

    2011-02-15

    In attosecond streaking, an electron is released by a short xuv pulse into a strong near infrared laser field. If the laser couples two states in the target, the streaking technique, which allows for a complete determination of the driving field, also gives an accurate measurement of the relative phase of the atomic or molecular ionization matrix elements from the two states through the interference from the two channels. The interference may change the phase of the photoelectron streaking signal within the envelope of the infrared field, an effect to be accounted for when reconstructing short pulses from the photoelectron signal and in attosecond time-resolved measurements.

  17. Streaking artifact reduction for quantitative susceptibility mapping of sources with large dynamic range.

    PubMed

    Wei, Hongjiang; Dibb, Russell; Zhou, Yan; Sun, Yawen; Xu, Jianrong; Wang, Nian; Liu, Chunlei

    2015-10-01

    Quantitative susceptibility mapping (QSM) is a novel MRI technique for the measurement of tissue magnetic susceptibility in three dimensions. Although numerous algorithms have been developed to solve this ill-posed inverse problem, the estimation of susceptibility maps with a wide range of values is still problematic. In cases such as large veins, contrast agent uptake and intracranial hemorrhages, extreme susceptibility values in focal areas cause severe streaking artifacts. To enable the reduction of these artifacts, whilst preserving subtle susceptibility contrast, a two-level QSM reconstruction algorithm (streaking artifact reduction for QSM, STAR-QSM) was developed in this study by tuning a regularization parameter to automatically reconstruct both large and small susceptibility values. Compared with current state-of-the-art QSM methods, such as the improved sparse linear equation and least-squares (iLSQR) algorithm, STAR-QSM significantly reduced the streaking artifacts, whilst preserving the sharp boundaries for blood vessels of mouse brains in vivo and fine anatomical details of high-resolution mouse brains ex vivo. Brain image data from patients with cerebral hematoma and multiple sclerosis further illustrated the superiority of this method in reducing streaking artifacts caused by large susceptibility sources, whilst maintaining sharp anatomical details. STAR-QSM is implemented in STI Suite, a comprehensive shareware for susceptibility imaging and quantification. PMID:26313885

  18. Performance comparison of streak camera recording systems

    SciTech Connect

    Derzon, M.; Barber, T.

    1995-07-01

    Streak camera based diagnostics are vital to the inertial confinement fusion program at Sandia National Laboratories. Performance characteristics of various readout systems coupled to an EGG-AVO streak camera were analyzed and compared to scaling estimates. The purpose of the work was to determine the limits of the streak camera performance and the optimal fielding conditions for the Amador Valley Operations (AVO) streak camera systems. The authors measured streak camera limitations in spatial resolution and sensitivity. Streak camera limits on spatial resolution are greater than 18 lp/mm at 4% contrast. However, it will be difficult to make use of any resolution greater than this because of high spatial frequency variation in the photocathode sensitivity. They have measured a signal to noise of 3,000 with 0.3 mW/cm{sup 2} of 830 nm light at a 10 ns/mm sweep speed. They have compared lens coupling systems with and without micro-channel plate intensifiers and systems using film or charge coupled device (CCD) readout. There were no conditions where film was found to be an improvement over the CCD readout. Systems utilizing a CCD readout without an intensifier have comparable resolution, for these source sizes and at a nominal cost in signal to noise of 3, over those with an intensifier. Estimates of the signal-to-noise for different light coupling methods show how performance can be improved.

  19. Gullies and Streaks on Crater wall Kaiser

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies emergent from a specific layer in the wall of an ancient crater within a much larger crater, Kaiser. Located at 46.4oS, 341.4oW, this picture obtained in early southern summer also shows a plethora of dark, and in some places squiggly, streaks. The streaks are thought to have been formed by the passage of dust devils that removed or disrupted a thin coating of dust from the surface. Such streaks commonly form at martian middle latitudes in late spring and early summer. The gullies in the crater wall were likely eroded by a fluid, perhaps water. This picture was obtained in January 2002; it covers an area 3 km (1.9 mi) across and is illuminated from the upper left.

  20. Varicose vein - noninvasive treatment

    MedlinePLUS

    ... The vein will harden and then disappear. Laser treatment can be used on the surface of the skin. Small bursts of light make small varicose veins disappear. Phlebectomy treats surface ... guide treatment. This may be done along with other procedures, ...

  1. Portal vein thrombosis.

    PubMed

    Cohen, Ronny; Mallet, Thierry; Gale, Michael; Soltys, Remigiusz; Loarte, Pablo

    2015-01-01

    Portal vein thrombosis (PVT) is the blockage or narrowing of the portal vein by a thrombus. It is relatively rare and has been linked with the presence of an underlying liver disease or prothrombotic disorders. We present a case of a young male who presented with vague abdominal symptoms for approximately one week. Imaging revealed the presence of multiple nonocclusive thrombi involving the right portal vein, the splenic vein, and the left renal vein, as well as complete occlusion of the left portal vein and the superior mesenteric vein. We discuss pathogenesis, clinical presentation, and management of both acute and chronic thrombosis. The presence of PVT should be considered as a clue for prothrombotic disorders, liver disease, and other local and general factors that must be carefully investigated. It is hoped that this case report will help increase awareness of the complexity associated with portal vein thrombosis among the medical community. PMID:25802795

  2. Focus on Varicose Veins

    MedlinePLUS

    ... veins no longer work. Under the pressure of gravity these veins can continue to expand and, in ... flow from the legs toward the heart against gravity, while preventing reverse flow back down the legs. ...

  3. Hot streak characterization in serpentine exhaust nozzles

    NASA Astrophysics Data System (ADS)

    Crowe, Darrell S.

    Modern aircraft of the United States Air Force face increasingly demanding cost, weight, and survivability requirements. Serpentine exhaust nozzles within an embedded engine allow a weapon system to fulfill mission survivability requirements by providing denial of direct line-of-sight into the high-temperature components of the engine. Recently, aircraft have experienced material degradation and failure along the aft deck due to extreme thermal loading. Failure has occurred in specific regions along the aft deck where concentrations of hot gas have come in contact with the surface causing hot streaks. The prevention of these failures will be aided by the accurate prediction of hot streaks. Additionally, hot streak prediction will improve future designs by identifying areas of the nozzle and aft deck surfaces that require thermal management. To this end, the goal of this research is to observe and characterize the underlying flow physics of hot streak phenomena. The goal is accomplished by applying computational fluid dynamics to determine how hot streak phenomena is affected by changes in nozzle geometry. The present research first validates the computational methods using serpentine inlet experimental and computational studies. A design methodology is then established for creating six serpentine exhaust nozzles investigated in this research. A grid independent solution is obtained on a nozzle using several figures of merit and the grid-convergence index method. An investigation into the application of a second-order closure turbulence model is accomplished. Simulations are performed for all serpentine nozzles at two flow conditions. The research introduces a set of characterization and performance parameters based on the temperature distribution and flow conditions at the nozzle throat and exit. Examination of the temperature distribution on the upper and lower nozzle surfaces reveals critical information concerning changes in hot streak phenomena due to changes in nozzle geometry.

  4. Frost streaks in the south polar cap of Mars

    NASA Technical Reports Server (NTRS)

    Thomas, P.; Veverka, J.; Campos-Marquetti, R.

    1979-01-01

    Viking Orbiter images of the annual south polar cap on Mars exhibit elongated bright features that are associated with craters and resemble wind streaks observed elsewhere on Mars. The study focuses on the well-documented frost streaks. The discussion covers the morphology of frost streaks, occurrence, seasonal behavior, thickness of frost in streak deposits, wind patterns inferred from frost streaks and other eolian features in the south polar region, formation of frost streaks, and other locales of preferential frost accumulation. The form and seasonal behavior of the bright elongated albedo markings which extend from the rims of many craters in the south polar cap suggest that they are accumulations of CO2 frost in the lee of craters. The frost streaks appear in the fall, increasing in length but not changing in direction during fall and winter. The frost streaks indicate a prograde circulation pattern of near-surface winds around the pole. Other details are also presented.

  5. Adding streamwise streaks in the plane Poiseuille flow

    NASA Astrophysics Data System (ADS)

    Hollands, Martin; Cossu, Carlo

    2009-03-01

    In recent investigations, finite amplitude streamwise streaks, generated with roughness elements, have been used to delay transition to turbulence. The maximum height of these roughness elements is limited by the appearance of instabilities in their near wake, therefore putting a limit on the maximum streak amplitude they can produce. Here we prove that large amplitude streaks can be generated by 'adding' lower amplitude streaks with multiple arrays of roughness elements. To cite this article: M. Hollands, C. Cossu, C. R. Mecanique 337 (2009).

  6. The first satellite laser echoes recorded on the streak camera

    NASA Technical Reports Server (NTRS)

    Hamal, Karel; Prochazka, Ivan; Kirchner, Georg; Koidl, F.

    1993-01-01

    The application of the streak camera with the circular sweep for the satellite laser ranging is described. The Modular Streak Camera system employing the circular sweep option was integrated into the conventional Satellite Laser System. The experimental satellite tracking and ranging has been performed. The first satellite laser echo streak camera records are presented.

  7. Perception of Randomness: On the Time of Streaks

    ERIC Educational Resources Information Center

    Sun, Yanlong; Wang, Hongbin

    2010-01-01

    People tend to think that streaks in random sequential events are rare and remarkable. When they actually encounter streaks, they tend to consider the underlying process as non-random. The present paper examines the time of pattern occurrences in sequences of Bernoulli trials, and shows that among all patterns of the same length, a streak is the

  8. Dark Streaks Over-riding Inactive Dunes

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Not all sand dunes on Mars are active in the modern martian environment. This example from the Lycus Sulci (Olympus Mons'aureole') region shows a case where small windblown dunes at the base of a slope have been over-ridden by more recent dark streaks (arrows). The dark streaks are most likely caused by what geologists call mass wasting or mass movement (landslides and avalanches are mass movements). Dark slope streaks such as these are common in dustier regions of Mars, and they appear to result from movement of extremely dry dust or sand in an almost fluidlike manner down a slope. This movement disrupts the bright dust coating on the surface and thus appears darker than the surrounding terrain.

    In this case, the dark slope streaks have moved up and over the dunes at the bottom of the slope, indicating that the process that moves sediment down the slope is more active (that is, it has occurred more recently and hence is more likely to occur) in the modern environment than is the movement of dunes and ripples at this location on Mars. The dunes, in fact, are probably mantled by dust. This October 1997 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture is illuminated from the left and located near 31.6oN, 134.0oW.

  9. Streaks Of Colored Water Indicate Surface Airflows

    NASA Technical Reports Server (NTRS)

    Wilcox, Floyd J., Jr.

    1994-01-01

    Response faster and contamination less than in oil-flow technique. Flowing colored water provides accurate and clean way to reveal flows of air on surfaces of models in wind tunnels. Colored water flows from small orifices in model, forming streak lines under influence of air streaming over surface of model.

  10. Martian Slope Streaks and Gullies: Origins as Dry Granular Flows

    NASA Technical Reports Server (NTRS)

    Treiman, A. H.; Louge, M. Y.

    2004-01-01

    Streaks and gullies are common on Martian slopes, and are geologically young; slope streaks have formed during the last few years of Mars Global Surveyor imaging. Both slope streaks and gullies involve flow of granular material, but it is not clear whether liquid water (or another suspending agent) was involved. The possibility that liquid water was involved makes gullies and slope streaks important for understanding Mars recent climate and for the hope of extant life near its surface. Here, we show that significant features of slope streaks and gullies are consistent with dry flows of granular material. Liquid water may not be required.

  11. Wind Streaks on Venus: Clues to Atmospheric Circulation

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Schubert, Gerald; Limonadi, Daniel; Bender, Kelly C.; Newman, William I.; Thomas, Peggy E.; Weitz, Catherine M.; Wall, Stephen D.

    1994-01-01

    Magellan images reveal surface features on Venus attributed to wind processes. Sand dunes, wind-sculpted hills, and more than 5830 wind streaks have been identified. The streaks serve as local "wind vanes," representing wind direction at the time of streak formation and allowing the first global mapping of near-surface wind patterns on Venus. Wind streaks are oriented both toward the equator and toward the west. When streaks associated with local transient events, such as impact cratering, are deleted, the westward component is mostly lost but the equatorward component remains. This pattern is consistent with a Hadley circulation of the lower atmosphere.

  12. Renal failure due to renal vein thrombosis in a fetus with growth restriction and thrombophilia.

    PubMed

    Has, Recep; Corbacioglu Esmer, Aytul; Kalelioglu, Ibrahim H; Yumru, Harika; Yüksel, Atil; Ziylan, Orhan

    2014-04-01

    We report a case of renal vein thrombosis diagnosed at 27 weeks of gestation in a dichorionic twin pregnancy. The left kidney of one fetus was hyperechoic and enlarged with echoic streaks following the direction of interlobular veins and the loss of corticomedullary differentiation. In the following weeks, left kidney became smaller and echoic, and Doppler examination showed no flow in both artery and vein. The right kidney had totally normal appearance in the beginning, but it became enlarged and hyperechoic, and progressed into a small echoic kidney with no flow in artery and vein. In the postnatal ultrasound examination, both kidneys appeared hyperechoic with no vascularization in the hilum region. There was thrombosis in arteries and veins of both kidneys, as well as in the inferior vena cava. The investigation for thrombophilia resulted with the combined presence of heterozygote mutation in factor V Leiden and prothrombin 20210 genes. PMID:24612313

  13. Yellow Fever Vaccine

    MedlinePLUS

    ... failure death (20 to 50% of serious cases) Yellow fever vaccine is a live, weakened virus. It is given ... a booster dose is recommended every 10 years.Yellow fever vaccine may be given at the same time as ...

  14. Photonic streaking of attosecond pulse trains

    NASA Astrophysics Data System (ADS)

    Kim, Kyung Taec; Zhang, Chunmei; Ruchon, Thierry; Hergott, Jean-Franois; Auguste, Thierry; Villeneuve, D. M.; Corkum, P. B.; Qur, F.

    2013-08-01

    High harmonic radiation, produced when intense laser pulses interact with matter, is composed of a train of attosecond pulses. Individual pulses in this train carry information on ultrafast dynamics that vary from one half-optical-cycle to the next. Here, we demonstrate an all-optical photonic streaking measurement that provides direct experimental access to each attosecond pulse by mapping emission time onto propagation angle. This is achieved by inducing an ultrafast rotation of the instantaneous laser wavefront at the focus. We thus time-resolve attosecond pulse train generation, and hence the dynamics in the nonlinear medium itself. We apply photonic streaking to harmonic generation in gases and directly observe, for the first time, the influence of non-adiabatic electron dynamics and plasma formation on the generated attosecond pulse train. These experimental and numerical results also provide the first evidence of the generation of attosecond lighthouses in gases, which constitute ideal sources for attosecond pump-probe spectroscopy.

  15. How accurate is the attosecond streak camera?

    PubMed

    Ivanov, Misha; Smirnova, Olga

    2011-11-18

    An attosecond streak camera holds the promise of time resolving the dynamics of photoionization with a few-attosecond accuracy. But can the attosecond measurement be disentangled from the process it measures? We address this question by deriving simple closed-form analytical expressions for the measurement-related apparent time delays in photoionization, associated with the application of the attosecond streak camera and/or resolution of attosecond beating by interference of two-photon transitions techniques. Our analytical results are accurate on about the 1 asec level and show that both intrinsic and measurement-induced delays depend on the same scattering phase and are, therefore, not independent. We also suggest a procedure for extracting intrinsic time delays from the measurement and a possible resolution of the controversy caused by the experiments of Schultze et al. [Science 328, 1658 (2010)]. PMID:22181882

  16. Interactive streak surface visualization on the GPU.

    PubMed

    Bürger, Kai; Ferstl, Florian; Theisel, Holger; Westermann, Rüdiger

    2009-01-01

    In this paper we present techniques for the visualization of unsteady flows using streak surfaces, which allow for the first time an adaptive integration and rendering of such surfaces in real-time. The techniques consist of two main components, which are both realized on the GPU to exploit computational and bandwidth capacities for numerical particle integration and to minimize bandwidth requirements in the rendering of the surface. In the construction stage, an adaptive surface representation is generated. Surface refinement and coarsening strategies are based on local surface properties like distortion and curvature. We compare two different methods to generate a streak surface: a) by computing a patch-based surface representation that avoids any interdependence between patches, and b) by computing a particle-based surface representation including particle connectivity, and by updating this connectivity during particle refinement and coarsening. In the rendering stage, the surface is either rendered as a set of quadrilateral surface patches using high-quality point-based approaches, or a surface triangulation is built in turn from the given particle connectivity and the resulting triangle mesh is rendered. We perform a comparative study of the proposed techniques with respect to surface quality, visual quality and performance by visualizing streak surfaces in real flows using different rendering options. PMID:19834197

  17. Understanding baseball team standings and streaks

    NASA Astrophysics Data System (ADS)

    Sire, C.; Redner, S.

    2009-02-01

    Can one understand the statistics of wins and losses of baseball teams? Are their consecutive-game winning and losing streaks self-reinforcing or can they be described statistically? We apply the Bradley-Terry model, which incorporates the heterogeneity of team strengths in a minimalist way, to answer these questions. Excellent agreement is found between the predictions of the Bradley-Terry model and the rank dependence of the average number team wins and losses in major-league baseball over the past century when the distribution of team strengths is taken to be uniformly distributed over a finite range. Using this uniform strength distribution, we also find very good agreement between model predictions and the observed distribution of consecutive-game team winning and losing streaks over the last half-century; however, the agreement is less good for the previous half-century. The behavior of the last half-century supports the hypothesis that long streaks are primarily statistical in origin with little self-reinforcing component. The data further show that the past half-century of baseball has been more competitive than the preceding half-century.

  18. Vein graft failure.

    PubMed

    Owens, Christopher D; Gasper, Warren J; Rahman, Amreen S; Conte, Michael S

    2015-01-01

    After the creation of an autogenous lower extremity bypass graft, the vein must undergo a series of dynamic structural changes to stabilize the arterial hemodynamic forces. These changes, which are commonly referred to as remodeling, include an inflammatory response, the development of a neointima, matrix turnover, and cellular proliferation and apoptosis. The sum total of these processes results in dramatic alterations in the physical and biomechanical attributes of the arterialized vein. The most clinically obvious and easily measured of these is lumen remodeling of the graft. However, although somewhat less precise, wall thickness, matrix composition, and endothelial changes can be measured in vivo within the healing vein graft. Recent translational work has demonstrated the clinical relevance of remodeling as it relates to vein graft patency and the systemic factors influencing it. By correlating histologic and molecular changes in the vein, insights into potential therapeutic strategies to prevent bypass failure and areas for future investigation are explored. PMID:24095042

  19. Vein graft failure

    PubMed Central

    Owens, Christopher D.; Gasper, Warren J.; Rahman, Amreen S.; Conte, Michael S

    2013-01-01

    Following the creation of an autogenous lower extremity bypass graft, the vein must undergo a series of dynamic structural changes to stabilize the arterial hemodynamic forces. These changes, commonly referred to as remodeling, include an inflammatory response, the development of a neointima, matrix turnover, and cellular proliferation and apoptosis. The sum total of these processes results in dramatic alterations in the physical and biomechanical attributes of the arterialized vein. The most clinically obvious and easily measured of these is lumen remodeling of the graft. However, though somewhat less precise, wall thickness, matrix composition, and endothelial changes can be measured in vivo within the healing vein graft. Recent translational work has demonstrated the clinical relevance of remodeling as it relates to vein graft patency and the systemic factors influencing it. By correlating histologic and molecular changes in the vein, insights into potential therapeutic strategies to prevent bypass failure and areas for future investigation are explored. PMID:24095042

  20. Spacing of Seeded and Spontaneous Streaks during Convective Deposition.

    PubMed

    Boettcher, Jane M; Joy, Midhun; Joshi, Kedar; Muangnapoh, Tanyakorn; Gilchrist, James F

    2015-10-13

    Convective deposition is widely used to deposit a highly ordered and uniform layer of monosized particles from solution by drawing the particles into an advancing thin film that uses capillary forces to define their local orientation. This process is often plagued by the formation of streaks, the regions where particles accumulate due to a local flux inhomogeneity. Flow occurs in the direction orthogonal to the deposition direction and parallel to the substrate near the streaks due to enhanced evaporation where particles have accumulated. This study investigates the formation of streaks nucleated from seeds or defects having prescribed dimensions and spacing across the substrate. The formation and spacing of both seeded and spontaneous streaks are characterized and were observed to be roughly dictated by the suspending fluid capillary length. Thus, spontaneously forming streaks can be suppressed by reducing the spacing to less than twice the critical length. Likewise, the conditions for maximum density or minimal spacing of streaks are also shown. PMID:26395545

  1. Opticla and X-Ray Streak Camera Gain Measurements

    SciTech Connect

    Ghosh, S.; Boni, R.; Jaanimagi, P.A.

    2004-10-19

    Measurements of streak camera gain as the number of CCD (charge-coupled-device) electrons recorded per single-electron events hitting the streak tube phosphor are presented. The CCD is fiber optically coupled to the streak tube output; there is no image intensifier in the system. The gain is measured from the signal-to-noise (SNR) ratio of the recorded photoelectrons. This technique allows us to verify that the photoelectron SNR follows Poisson statistics and to establish the linear dynamic range.

  2. Compressible laminar streaks with wall suction

    NASA Astrophysics Data System (ADS)

    Ricco, Pierre; Shah, Daniel; Hicks, Peter D.

    2013-05-01

    The response of a compressible laminar boundary layer subject to free-stream vortical disturbances and steady mean-flow wall suction is studied. The theoretical frameworks of Leib et al. [J. Fluid Mech. 380, 169-203 (1999), 10.1017/S0022112098003504] and Ricco and Wu [J. Fluid Mech. 587, 97-138 (2007), 10.1017/S0022112007007070], based on the linearized unsteady boundary-region equations, are adopted to study the influence of suction on the kinematic and thermal streaks arising through the interaction between the free-stream vortical perturbations and the boundary layer. In the asymptotic limit of small spanwise wavelength compared with the boundary layer thickness, i.e., when the disturbance flow is conveniently described by the steady compressible boundary region equations, the effect of suction is mild on the velocity fluctuations and negligible on the temperature fluctuations. When the spanwise wavelength is comparable with the boundary layer thickness, small suction values intensify the supersonic streaks, while higher transpiration levels always stabilize the disturbances at all Mach numbers. At larger spanwise wavelengths, very small amplitudes of wall transpiration have a dramatic stabilizing effect on all boundary layer fluctuations, which can take the form of transiently growing thermal streaks, large amplitude streamwise oscillations, or oblique exponentially growing Tollmien-Schlichting waves, depending on the Mach number and the wavelengths. The range of wavenumbers for which the exponential growth occurs becomes narrower and the location of instability is significantly shifted downstream by mild suction, indicating that wall transpiration can be a suitable vehicle for delaying transition when the laminar breakdown is promoted by these unstable disturbances. The typical streamwise wavelength of these disturbances is instead not influenced by suction, and asymptotic triple deck theory predicts the strong changes in growth rate and the very mild modifications in streamwise wavenumber in the limit of larger downstream distance and small spanwise wavenumber.

  3. X-ray streak crystal spectography

    SciTech Connect

    Kauffman, R.L.; Brown, T.; Medecki, H.

    1983-07-01

    We have built an x-ray streaked crystal spectrograph for making time-resolved x-ray spectral measurements. This instrument can access Bragg angles from 11/sup 0/ to 38/sup 0/ and x-ray spectra from 200 eV to greater than 10 keV. We have demonstrated resolving powers, E/..delta..E > 200 at 1 keV and time resolution less than 20 psec. A description of the instrument and an example of the data is given.

  4. Mass movement slope streaks imaged by the Mars Orbiter Camera

    NASA Astrophysics Data System (ADS)

    Sullivan, Robert; Thomas, Peter; Veverka, Joseph; Malin, Michael; Edgett, Kenneth S.

    2001-10-01

    Narrow, fan-shaped dark streaks on steep Martian slopes were originally observed in Viking Orbiter images, but a definitive explanation was not possible because of resolution limitations. Pictures acquired by the Mars Orbiter Camera (MOC) aboard the Mars Global Surveyor (MGS) spacecraft show innumerable examples of dark slope streaks distributed widely, but not uniformly, across the brighter equatorial regions, as well as individual details of these features that were not visible in Viking Orbiter data. Dark slope streaks (as well as much rarer bright slope streaks) represent one of the most widespread and easily recognized styles of mass movement currently affecting the Martian surface. New dark streaks have formed since Viking and even during the MGS mission, confirming earlier suppositions that higher contrast dark streaks are younger, and fade (brighten) with time. The darkest slope streaks represent ~10% contrast with surrounding slope materials. No small outcrops supplying dark material (or bright material, for bright streaks) have been found at streak apexes. Digitate downslope ends indicate slope streak formation involves a ground-hugging flow subject to deflection by minor topographic obstacles. The model we favor explains most dark slope streaks as scars from dust avalanches following oversteepening of air fall deposits. This process is analogous to terrestrial avalanches of oversteepened dry, loose snow which produce shallow avalanche scars with similar morphologies. Low angles of internal friction typically 10-30 for terrestrial loess and clay materials suggest that mass movement of (low-cohesion) Martian dusty air fall is possible on a wide range of gradients. Martian gravity, presumed low density of the air fall deposits, and thin (unresolved by MOC) failed layer depths imply extremely low cohesive strength at time of failure, consistent with expectations for an air fall deposit of dust particles. As speed increases during a dust avalanche, a growing fraction of the avalanching dust particles acquires sufficient kinetic energy to be lost to the atmosphere in suspension, limiting the momentum of the descending avalanche front. The equilibrium speed, where rate of mass lost to the atmosphere is balanced by mass continually entrained as the avalanche front descends, decreases with decreasing gradient. This mechanism explains observations from MOC images indicating slope streaks formed with little reserve kinetic energy for run-outs on to valley floors and explains why large distal deposits of displaced material are not found at downslope streak ends. The mass movement process of dark (and bright) slope streak formation through dust avalanches involves renewable sources of dust only, leaving underlying slope materials unaffected. Areas where dark and bright slope streaks currently form and fade in cycles are closely correlated with low thermal inertia and probably represent regions where dust currently is accumulating, not just residing.

  5. Standard varicose vein surgery.

    PubMed

    Perkins, J M T

    2009-01-01

    This article examines the practice of standard varicose vein surgery including sapheno-femoral and sapheno-popliteal ligation, perforator surgery and surgery for recurrent varicose veins. The technique of exposure of the sapheno-femoral junction and the sapheno-popliteal junction is outlined and advice given on avoidance of complications for both. The evidence regarding methods of closure over the ligated sapheno-femoral junction is examined as is the requirement for stripping and the use of different types of stripper. The requirement to strip the small saphenous vein and the extent of dissection necessary in the popliteal fossa is also examined. Complications of standard varicose vein surgery are outlined. The frequency of wound infection, nerve injury, vascular injury and venous thromboembolism are listed and strategies to avoid these complications are examined. PMID:19307439

  6. What Are Varicose Veins?

    MedlinePLUS

    ... body in the veins is darker because your body parts have used up the oxygen in the blood. ... on the legs, ankles, and feet because those body parts are farthest from the heart. Gravity pulls blood ...

  7. Varicose vein stripping

    MedlinePLUS

    ... ankle. Your surgeon will then thread a thin, flexible plastic wire into the vein through your groin ... Your legs will be wrapped with bandages to control swelling and bleeding for 3 to 5 days ...

  8. Deep vein thrombosis - discharge

    MedlinePLUS

    You were treated for deep venous thrombosis (DVT). This is a condition in which a blood clot forms in a vein that is not on ... especially if it gets worse upon taking a deep breath in You cough up blood

  9. Mesenteric vein thrombosis: CT identification

    SciTech Connect

    Rosen, A.; Korobkin, M.; Silverman, P.M.; Dunnick, N.R.; Kelvin, F.M.

    1984-07-01

    Superior mesenteric vein thrombosis was identified on computed tomographic scans in six patients. In each case, contrast-enhanced scans showed a high-density superior mesenteric vein wall surrounding a central filling defect. Four fo the six patients had isolated superior mesenteric vein thrombosis. A fifth patient had associated portal vein and splenic vein thrombosis, and the sixth patient had associated portal vein and inferior vena cava thrombosis. One of the six patients had acute ischemic bowel disease. The other five patients did not have acute ischemic bowel symptoms associated with their venous occlusion. This study defines the computed tomographic appearance of mesenteric vein thrombosis.

  10. Reducing streak film data via electronic cross correlator

    NASA Technical Reports Server (NTRS)

    Dickerson, R. A.

    1970-01-01

    Continuous /nonframing/ motion picture projector, two photocells, a cross-correlator, and a ground glass screen where the photocells intercept the stream image determine the time delay between successive streak images. Velocities corresponding to the streaks are determined from the delay together with the distance separating the photocells.

  11. Barley Yellow Dwarf Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley yellow dwarf (BYD) is the most widespread and economically important virus disease of cereals. The viruses causing BYD were initially grouped based on common biological properties, including persistent and often strain-specific transmission by aphids and induction of yellowing symptoms. The...

  12. The study of streak camera dynamic distortion

    NASA Astrophysics Data System (ADS)

    Deng, Bo; Li, Jing; Chen, Tao; Hu, Xin; Liu, Shenye

    2012-10-01

    Dynamic distortion, which is caused by space-charge effect, widely exists in streak camera. When input light intensity becomes too large, the electric field caused by electric beam turns out analogous to that caused by image converter tube, which leads to the dynamic distortion. In this article, we analyze the theory of the dynamic distortion by experiments and simulations upon CST Particle Studio software. Results show that: the intensity of current and the space position along the photocathode shall affect the dynamic distortion, leading to defocusing effect and reduce both the spatial resolution and the temporal resolution. All above assist us to better understand the electric-optic system of image converter tube, and provide ideas for further experimental diagnose design.

  13. Comparative analysis of Panicum streak virus and Maize streak virus diversity, recombination patterns and phylogeography

    PubMed Central

    2009-01-01

    Background Panicum streak virus (PanSV; Family Geminiviridae; Genus Mastrevirus) is a close relative of Maize streak virus (MSV), the most serious viral threat to maize production in Africa. PanSV and MSV have the same leafhopper vector species, largely overlapping natural host ranges and similar geographical distributions across Africa and its associated Indian Ocean Islands. Unlike MSV, however, PanSV has no known economic relevance. Results Here we report on 16 new PanSV full genome sequences sampled throughout Africa and use these together with others in public databases to reveal that PanSV and MSV populations in general share very similar patterns of genetic exchange and geographically structured diversity. A potentially important difference between the species, however, is that the movement of MSV strains throughout Africa is apparently less constrained than that of PanSV strains. Interestingly the MSV-A strain which causes maize streak disease is apparently the most mobile of all the PanSV and MSV strains investigated. Conclusion We therefore hypothesize that the generally increased mobility of MSV relative to other closely related species such as PanSV, may have been an important evolutionary step in the eventual emergence of MSV-A as a serious agricultural pathogen. The GenBank accession numbers for the sequences reported in this paper are GQ415386-GQ415401 PMID:19903330

  14. Ovarian vein thrombosis

    PubMed Central

    Jenayah, Amel Achour; Saoudi, Sarra; Boudaya, Fethia; Bouriel, Ines; Sfar, Ezzeddine; Chelli, Dalenda

    2015-01-01

    Ovarian vein thrombosis (OVT) is a rare cause of abdominal pain that may mimic a surgical abdomen. It is most often diagnosed during the postpartum period. In this report, we present four cases of postoperative ovarian vein thrombosis. The complications of OVT can be significant, and the diagnosis relies on a careful examination of the radiographic findings. It can occur with lower quadrant abdominal pain, especially in the setting of recent pregnancy, abdominal surgery, pelvic inflammatory disease, or malignancy. Diagnosis can be made with confidence using ultrasound, computed tomography or magnetic resonance imaging. Treatment of ovarian vein thrombosis is particularly important in the post-partum patients, with anticoagulation therapy being the current recommendation. PMID:26526119

  15. Pelvic Vein Embolisation in the Management of Varicose Veins

    SciTech Connect

    Ratnam, Lakshmi A.; Marsh, Petra; Holdstock, Judy M.; Harrison, Charmaine S.; Hussain, Fuad F.; Whiteley, Mark S.; Lopez, Anthony

    2008-11-15

    Pelvic vein incompetence is common in patients with atypical varicose veins, contributing to their recurrence after surgery. Therefore, refluxing pelvic veins should be identified and treated. We present our experience with pelvic vein embolisation in patients presenting with varicose veins. Patients presenting with varicose veins with a duplex-proven contribution from perivulval veins undergo transvaginal duplex sonography (TVUS) to identify refluxing pelvic veins. Those with positive scans undergo embolisation before surgical treatment of their lower limb varicose veins. A total of 218 women (mean age of 46.3 years) were treated. Parity was documented in the first 60 patients, of whom 47 (78.3%) were multiparous, 11 (18.3%) had had one previous pregnancy, and 2 (3.3%) were nulliparous. The left ovarian vein was embolised in 78%, the right internal iliac in 64.7%, the left internal iliac in 56.4%, and the right ovarian vein in 42.2% of patients. At follow-up TVUS, mild reflux only was seen in 16, marked persistent reflux in 6, and new reflux in 3 patients. These 9 women underwent successful repeat embolisation. Two patients experienced pulmonary embolisation of the coils, of whom 1 was asymptomatic and 1 was successfully retrieved; 1 patient had a misplaced coil protruding into the common femoral vein; and 1 patient had perineal thrombophlebitis. The results of our study showed that pelvic venous embolisation by way of a transjugular approach is a safe and effective technique in the treatment of pelvic vein reflux.

  16. A Performance Evaluation Of Three High-Fidelity Streak Cameras

    NASA Astrophysics Data System (ADS)

    Bonlie, James D.; Lowry, Mark E.

    1989-02-01

    Several scientific programs at Lawrence Livermore National Laboratory (LLNL) require instrumentation that can capture optical signals with high fidelity. Typically, they require high temporal resolution, high spatial resolution, and high dynamic range. The instrument of choice for most of these multichannel, data-recording applications is the optical streak camera. We have evaluated three optical streak camera systems under similar conditions: (1) the EG&G model L-CA-15 streak camera, designed and built under U.S. Department of Energy (DOE) contract, with a streak tube designed for a time response of a few picoseconds; (2) an in-house (LLNL) design, with an ITT F4157 streak tube that operates in the extraction mode; and (3) a Thomson-CSF model TSN 506 streak camera, with an ITT F4157 streak tube that also operates in the extraction mode. All three systems were found to be capable of time response better than 40 ps FWHM, a dynamic range of greater than 100, and spatial resolution greater than 5 line pairs per millimeter (lp/mm). The experimental setup and plots of results are presented and discussed.

  17. High Performance Imaging Streak Camera for the National Ignition Facility

    SciTech Connect

    Opachich, Y. P.; Kalantar, D.; MacPhee, A.; Holder, J.; Kimbrough, J.; Bell, P. M.; Bradley, D.; Hatch, B.; Brown, C.; Landen, O.; Perfect, B. H.; Guidry, B.; Mead, A.; Charest, M.; Palmer, N.; Homoelle, D.; Browning, D.; Silbernagel, C.; Brienza-Larsen, G.; Griffin, M.; Lee, J. J.; Haugh, M. J.

    2012-01-01

    An x-ray streak camera platform has been characterized and implemented for use at the National Ignition Facility. The camera has been modified to meet the experiment requirements of the National Ignition Campaign and to perform reliably in conditions that produce high EMI. A train of temporal UV timing markers has been added to the diagnostic in order to calibrate the temporal axis of the instrument and the detector efficiency of the streak camera was improved by using a CsI photocathode. The performance of the streak camera has been characterized and is summarized in this paper. The detector efficiency and cathode measurements are also presented.

  18. Progress on Modeling of Ultrafast X-Ray Streak Cameras

    SciTech Connect

    Huang, G.; Byrd, J.M.; Feng, J.; Qiang, J.; Wang, W.

    2007-06-22

    Streak cameras continue to be useful tools for studying phenomena on the picoseconds time scale. We have employed accelerator modeling tools to understand and possibly improve the time resolution of present and future streak cameras. This effort has resulted in an end-to-end model of the camera. This model has contributed to the recent measurement of 230 fsec (FWHM) resolution measured at 266 nm in the Advanced Light Source Streak Camera Laboratory. We describe results from this model that show agreement with the experiments. We also extrapolate the performance of this camera including several possible improvements.

  19. High performance imaging streak camera for the National Ignition Facility.

    PubMed

    Opachich, Y P; Kalantar, D H; MacPhee, A G; Holder, J P; Kimbrough, J R; Bell, P M; Bradley, D K; Hatch, B; Brienza-Larsen, G; Brown, C; Brown, C G; Browning, D; Charest, M; Dewald, E L; Griffin, M; Guidry, B; Haugh, M J; Hicks, D G; Homoelle, D; Lee, J J; Mackinnon, A J; Mead, A; Palmer, N; Perfect, B H; Ross, J S; Silbernagel, C; Landen, O

    2012-12-01

    An x-ray streak camera platform has been characterized and implemented for use at the National Ignition Facility. The camera has been modified to meet the experiment requirements of the National Ignition Campaign and to perform reliably in conditions that produce high electromagnetic interference. A train of temporal ultra-violet timing markers has been added to the diagnostic in order to calibrate the temporal axis of the instrument and the detector efficiency of the streak camera was improved by using a CsI photocathode. The performance of the streak camera has been characterized and is summarized in this paper. The detector efficiency and cathode measurements are also presented. PMID:23278024

  20. Streak tube photocathode development program. Phase 2, Final technical report

    SciTech Connect

    Not Available

    1993-11-20

    This report details the progress made toward developing a streak tube with greater than 1% quantum efficiency at a wavelength of 1300 nm. The achieved performance is the result of approximately three years of effort. The goal of Phase 2 of this contract was to seal a working 1.3 {mu}m streak tube. This effort was focused in two areas. First there was a continuing effort to further develop and demonstrate the cathodes ability to meet the stated requirements. The second effort was aimed at solving the mechanical and process related problems related to sealing this cathode onto a EG&G streak tube.

  1. Temporal Contrast Changes in Dark Slope Streaks on Mars

    NASA Astrophysics Data System (ADS)

    Chilton, H.; Phillips, C. B.; Fenton, L. K.; Brown, A. J.

    2012-12-01

    Dark slope streaks on Mars, first observed in Viking images, provide insight into one of the most active and dynamic processes observed on the planet's surface. While various formation models have been suggested [1][2][3], dust avalanches seem to best explain streak origin and characteristics[4][5]. New dark streaks are observed to have the greatest contrast to their surroundings while older streaks have lower contrast, suggesting that streaks fade over time. One theory for this is atmospheric dust fallout slowly raising the albedo of the surface exposed by the dust avalanche, resulting in increased streak albedo over time until the streak becomes indistinguishable from the surrounding surface. In this study, we attempt an initial evaluation of changes in streak brightness relative to surroundings, with a first order correction for incidence angle[6] based on MOLA data. CRISM images were first identified for spatial and temporal overlap, then further selected for those image sets with well-matched viewing geometries. Locations included Nicholson Crater (CRISM images: frt0000c287_07_de165l, hrl0000d0f1_7_de165l, frt00018c69_07_de165l) and South of Nestus Valles (CRISM images: hrl00004a5e_07_de181l, hrl0000812a_07_de182l) as well as Naktong Vallis (CRISM images: hrl0000898d_07_de182l, hrl00005337_07_de182l) and an area in Lycus Sulci (CRISM images: hrl0000a52a_07_de166l, hrl0000ce5f_07_if175l). We focused on 1 micron wavelength CRISM images in order to reduce atmosphric interference. From here, brightness (observed radiance divided by solar irradiance at Mars divided by pi) values were collected along individual streaks, with measurements at multiple locations along the streak length and alongside at points of similar elevation to streak measurements to establish an average contrast ratio. Both on-streak and off-streak values were divided by the cosine of their respective local MOLA incidence angles to correct for brightness variation due to solar flux and topographic angles. These measurements were then repeated for overlapping temporal images, establishing local and overall averages for the rate of change in this contrast ratio. While our initial hypothesis was for linear streak fading, results showed a range of trends, including streaks and imaged areas with streaks that darkened, brightened, and brightened then darkened or vice versa. We continue to explore the possibility of non-linear brightening as well as streak reactivation and localized events, surface characteristics, and topography. Further study will focus on these and other morphological changes observed from vast data sets of other instruments including the Mars Reconnaissance Orbter HiRISE and CTX, Mars Express HRSC, Mars Odyssey THEMIS (visible), and the Mars Global Surveyor MOC. [1] Morris (1982) JGR, 87, 1164-1178. [2] Ferguson and Lucchita (1984) NASA Tech. Memo., TM-86246, 188-190. [3] Miyamoto, H. et al. (2004) JGR, 109, E06008. [4] Sullivan, R. et al. (2001) JGR, 106, 23607-23633. [5] Baratoux, N. M. et al. (2006) Icarus, 183, 30-45. [6] Brown, A. et al. (2010) JGR, 115, E00D13.

  2. [Deep vein thrombosis prophylaxis.

    PubMed

    Sandoval-Chagoya, Gloria Alejandra; Laniado-Laborn, Rafael

    2013-01-01

    Background: despite the proven effectiveness of preventive therapy for deep vein thrombosis, a significant proportion of patients at risk for thromboembolism do not receive prophylaxis during hospitalization. Our objective was to determine the adherence to thrombosis prophylaxis guidelines in a general hospital as a quality control strategy. Methods: a random audit of clinical charts was conducted at the Tijuana General Hospital, Baja California, Mexico, to determine the degree of adherence to deep vein thrombosis prophylaxis guidelines. The instrument used was the Caprini's checklist for thrombosis risk assessment in adult patients. Results: the sample included 300 patient charts; 182 (60.7 %) were surgical patients and 118 were medical patients. Forty six patients (15.3 %) received deep vein thrombosis pharmacologic prophylaxis; 27.1 % of medical patients received deep vein thrombosis prophylaxis versus 8.3 % of surgical patients (p < 0.0001). Conclusions: our results show that adherence to DVT prophylaxis at our hospital is extremely low. Only 15.3 % of our patients at risk received treatment, and even patients with very high risk received treatment in less than 25 % of the cases. We have implemented strategies to increase compliance with clinical guidelines. PMID:24290023

  3. Living with Deep Vein Thrombosis

    MedlinePLUS

    ... page from the NHLBI on Twitter. Living With Deep Vein Thrombosis NHLBI Resources Pulmonary Embolism (Health Topics) Non-NHLBI Resources Deep Vein Thrombosis (MedlinePlus) Pulmonary Embolism (MedlinePlus) Clinical Trials ...

  4. Yellow Legged Frog

    USGS Multimedia Gallery

    USGS scientists found this adult mountain yellow-legged frog on June 10 in Tahquitz Creek, a rediscovered population of the endangered frog in the San Jacinto Wilderness, San Bernardino National Forest, California....

  5. Travelers' Health: Yellow Fever

    MedlinePLUS

    ... to-human) transmission occurring. There are 3 transmission cycles for yellow fever: sylvatic (jungle), intermediate (savannah), and urban. The sylvatic (jungle) cycle involves transmission of the virus between nonhuman primates ...

  6. Note: X-ray streak camera sweep speed calibration.

    PubMed

    Zhu, Tuo; Yang, Jia-Min; Deng, Bo; Yang, Dong; He, Xiao-an; Wang, Zhe-bin

    2010-05-01

    X-ray streak cameras are extensively used to study transient x-ray processes in experiments carried out on various laser facilities at the Research Center of Laser Fusion. Precise calibration and clear description of the sweep speed of the x-ray streak camera are vital for obtaining precise temporal information to understand the fast physics phenomena. An x-ray streak camera named wide-slit x-ray streak camera has been calibrated using a small-scale laser facility with pulse duration of 8 ps. Sweep speeds on most part of the output screen (charge coupled device) are obtained. These calibration results can be used to correct the nonlinearity of sweep speed in measurement of temporal processes. PMID:20515185

  7. Collateral veins in left renal vein stenosis demonstrated via CT.

    PubMed

    Lien, H H; Lund, G; Talle, K

    1983-02-01

    Twelve patients with left renal vein stenosis from tumor compression were studied with CT. All had distended collateral veins in the perirenal space which either formed a radiating or a cobweb pattern or appeared as marked longitudinal veins. Inferior phrenic vein branches were seen in seven patients and were considerably enlarged in two. Other major veins possibly taking part in collateral circulation could not be recognized due to obliteration of fat planes. The renal fascia was thickened in eleven patients, probably due to edema. A close study of the perirenal space with CT may give valuable information about collateral development. PMID:6840101

  8. Active Processes: Bright Streaks and Dark Fans

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

    In a region of the south pole known informally as 'Ithaca' numerous fans of dark frost form every spring. HiRISE collected a time lapse series of these images, starting at Ls = 185 and culminating at Ls = 294. 'Ls' is the way we measure time on Mars: at Ls = 180 the sun passes the equator on its way south; at Ls = 270 it reaches its maximum subsolar latitude and summer begins.

    In the earliest image (figure 1) fans are dark, but small narrow bright streaks can be detected. In the next image (figure 2), acquired at Ls = 187, just 106 hours later, dramatic differences are apparent. The dark fans are larger and the bright fans are more pronounced and easily detectable. The third image in the sequence shows no bright fans at all.

    We believe that the bright streaks are fine frost condensed from the gas exiting the vent. The conditions must be just right for the bright frost to condense.

    Observation Geometry Image PSP_002622_0945 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 16-Feb-2007. The complete image is centered at -85.2 degrees latitude, 181.5 degrees East longitude. The range to the target site was 246.9 km (154.3 miles). At this distance the image scale is 49.4 cm/pixel (with 2 x 2 binning) so objects 148 cm across are resolved. The image shown here has been map-projected to 50 cm/pixel . The image was taken at a local Mars time of 05:46 PM and the scene is illuminated from the west with a solar incidence angle of 88 degrees, thus the sun was about 2 degrees above the horizon. At a solar longitude of 185.1 degrees, the season on Mars is Northern Autumn.

  9. Visual and infrared observations of wind streaks on Mars

    NASA Astrophysics Data System (ADS)

    Peterfreund, A. R.

    1981-02-01

    Global correlations of the regions in which three Martian wind streak types (bright, dark, splotch-related) vary according to latitude, elevation, albedo, color, and predawn residual temperature provide constraints on models of streak formation and modification. Bright streaks are relatively stable and occur over a wide range of geographical surfaces. They are elevation-independent, suggesting that their formation is due to atmospheric dust fallout. Dark streaks appear variable from 20 to 40 deg S and at elevations between 3 and 7 km. They are associated with dark surfaces, having high thermal inertias. Splotch-related streaks occur at elevations between 0 and 6 km and at areas of either low or high thermal inertias, which is the cause of its modifying surface winds. Data are graphically presented, and the methods of data collection are fully explained. Regional studies of various types of streaks in Syrtis Major, Syria Planum, Oxia Palus, Mesogea and Pettit Craters, and Noachis confirm that the correlations found at the global level also occur at regional scales.

  10. Streak image denoising and segmentation using adaptive Gaussian guided filter.

    PubMed

    Jiang, Zhuocheng; Guo, Baoping

    2014-09-10

    In streak tube imaging lidar (STIL), streak images are obtained using a CCD camera. However, noise in the captured streak images can greatly affect the quality of reconstructed 3D contrast and range images. The greatest challenge for streak image denoising is reducing the noise while preserving details. In this paper, we propose an adaptive Gaussian guided filter (AGGF) for noise removal and detail enhancement of streak images. The proposed algorithm is based on a guided filter (GF) and part of an adaptive bilateral filter (ABF). In the AGGF, the details are enhanced by optimizing the offset parameter. AGGF-denoised streak images are significantly sharper than those denoised by the GF. Moreover, the AGGF is a fast linear time algorithm achieved by recursively implementing a Gaussian filter kernel. Experimentally, AGGF demonstrates its capacity to preserve edges and thin structures and outperforms the existing bilateral filter and domain transform filter in terms of both visual quality and peak signal-to-noise ratio performance. PMID:25321679

  11. The effect of the attochirp on attosecond streaking

    NASA Astrophysics Data System (ADS)

    Goldsmith, Cory; Jaron-Becker, Agnieszka; Becker, Andreas

    2015-05-01

    Measurements invoking the use of attosecond pulses can be incorrectly interpreted if the chirp of such pulses is not taken into account. In this study, we use a physically intuitive analytical model to understand the effect a chirp in the extreme ultraviolet (XUV) attosecond pulse will have upon the delay observed in streaking experiments. It is known that both the photoionization cross-section of the system and the spectral and temporal characteristics of the attosecond pulse used will determine the relative time-dependent probability of absorbing a particular photon energy. We additionally use an analytical method to calculate the streaking delay as a function of the absorbed photon energy and the time delay between the XUV and streaking pulses. Equipped with this information, we determine the expected value of the streaking delay observed when a chirped attosecond XUV pulse is used to initiate streaking experiments. We then demonstrate that depending on the chirp, the streaking delay can be changed by several attoseconds, which is on the order of the delays usually observed in such experiments. We acknowledge the following support: C.G. and A.B: U.S. DOE, Division of Chemical Sciences, Atomic, Molecular and Optical Sciences Program (Award No. DE-FG02-09ER16103), A.J.-B.: U.S. NSF (Grants No. PHY-1125844 and No. PHY-1068706).

  12. Study of Geometric Parameters of Slope Streaks on Mars.

    NASA Astrophysics Data System (ADS)

    Brusnikin, Eugene; Kreslavsky, Mikhail; Karachevtseva, Irina; Zubarev, Anatoliy; Patratiy, Vyacheslav

    2015-04-01

    Slope streaks are a unique active phenomenon observed in low-latitude dusty regions on Mars. They are dark markings formed by an unknown type of run-away downslope propagation of surface disturbance. There are two kinds of hypotheses of their formation mechanism: "dry", involving granular follow, in particular, dust avalanche, and "wet", involving liquid flow, in particular, percolation of concentrated brines in shallow subsurface (1). Study of geometric characteristics of the slope streaks, especially their slopes, is a way to decipher their origin. We are carrying out an extensive set of measurements of geometric parameters of the slope streaks. We use stereo pairs of images obtained by High Resolution Imaging Science Experiment (HiRISE) onboard MRO orbital mission to Mars. These stereo pairs potentially allow geometric measurements (both horizontal and vertical) with accuracy on an order of a meter. Unfortunately, the digital terrain model is currently released for only one stereo pair in the regions of slope streak occurrence, and we have to work with raw, unprocessed stereo pairs. We perform direct photogrammetric measurements using PHOTOMOD software complex (http://www.racurs.ru/). We use our custom software to import "raw" HiRISE imgas (EDRs) and supplementary geometric information from SPICE into PHOTOMOD (2). We select tens to a hundred meters long segments in the beginning and the end of selected streaks and register length, azimuth, and slope of each segment. We also search for anomalously gentle parts of streaks. We analyze the obtained results by means of ESRI ArcGIS software. Our survey is in progress. So far we registered over a hundred of streaks. We found that the extent of the streaks varies from several meters to hundreds of meters. The streaks are formed in locales with a slope from 17 to 37 degrees. The lower boundary indicates that the streaks can propagate on slopes that are significantly gentler than the static angle of repose. Distal (downslope) termini of the streaks often are in rather flat sites. So far we have not found any convincing example of a streak propagating uphill. This is consistent with earlier conclusions that the streaks do not have appreciable inertia. We will continue our survey. With more data we will correlate streak formation and their slopes with slope orientation, latitude, etc. This work was carried out in MIIGAiK and supported by Russian Science Foundation, project 14-22-00197. References: 1. Kreslavsky A.M. and J. W. Head, Slope streaks on Mars: A new "wet" mechanism, Icarus 201, 517-527 (2009). 2. Zubarev A., Nadezhdina I. Alignment-Calibration and Processing of HIRISE CCD Data // ISPRS Meeting of the Working Group IV/8 "Advances in Planetary Mapping and Spatial Databases", Moscow, Russia, October 09-12, 2013

  13. Deep vein thrombosis.

    PubMed

    Emanuele, Patricia

    2008-09-01

    This article reviews the incidence, causes, risk factors, diagnosis, treatment, complications, and prevention of deep vein thrombosis (DVT). Various employees, including long-distance drivers or travelers, sedentary office workers, females taking estrogen, those who are obese, those who have cancer, and those who are hospitalized, may be at risk for developing this condition. Genetic testing can determine some inherited factors predisposing workers to clotting. Low-molecular weight heparins can be used to manage DVT on an outpatient basis. PMID:18792613

  14. Streak detection and analysis pipeline for optical images

    NASA Astrophysics Data System (ADS)

    Virtanen, J.; Granvik, M.; Torppa, J.; Muinonen, K.; Poikonen, J.; Lehti, J.; Säntti, T.; Komulainen, T.; Flohrer, T.

    2014-07-01

    We describe a novel data processing and analysis pipeline for optical observations of moving objects, either of natural (asteroids, meteors) or artificial origin (satellites, space debris). The monitoring of the space object populations requires reliable acquisition of observational data to support the development and validation of population models, and to build and maintain catalogues of orbital elements. The orbital catalogues are, in turn, needed for the assessment of close approaches (for asteroids, with the Earth; for satellites, with each other) and for the support of contingency situations or launches. For both types of populations, there is also increasing interest to detect fainter objects corresponding to the small end of the size distribution. We focus on the low signal-to-noise (SNR) detection of objects with high angular velocities, resulting in long and faint object trails, or streaks, in the optical images. The currently available, mature image processing algorithms for detection and astrometric reduction of optical data cover objects that cross the sensor field-of-view comparably slowly, and, particularly for satellites, within a rather narrow, predefined range of angular velocities. By applying specific tracking techniques, the objects appear point-like or as short trails in the exposures. However, the general survey scenario is always a 'track-before-detect' problem, resulting in streaks of arbitrary lengths. Although some considerations for low-SNR processing of streak-like features are available in the current image processing and computer vision literature, algorithms are not readily available yet. In the ESA-funded StreakDet (Streak detection and astrometric reduction) project, we develop and evaluate an automated processing pipeline applicable to single images (as compared to consecutive frames of the same field) obtained with any observing scenario, including space-based surveys and both low- and high-altitude populations. The algorithmic flow starts from the segmentation of the acquired image (i.e., the extraction of all sources), followed by the astrometric and photometric characterization of the candidate streaks, and ends with orbital validation of the detected streaks. For the low-SNR extraction of objects, we put forward an approach which does not rely on a priori information, such as the object velocities, a typical assumption in earlier implementations. Our algorithm is based on local grayscale mean difference evaluation, followed by a threshold operation and spatial filtering of black-and-white (1-bit) data to remove stars and other non-streak features. For long streaks, the challenge is to extract position information and related registered epochs with sufficient precision. Moreover, satellite streaks can show up in complex morphologies because of their fast, and often irregular lightcurve variations. A central concept of the pipeline is streak classification which guides the actual characterization process by aiming to identify the interesting sources and to filter out the uninteresting ones, as well as by allowing the tailoring of algorithms for specific streak classes (e.g. PSF fitting for point-like vs. long, disintegrated streaks). Finally, to validate the single-image detections, the processing is finalized by orbital analysis using our statistical inverse methods (see, Muinonen et al., this conference), resulting in preliminary orbital classification (e.g., Earth-bound vs. non-Earth-bound orbits) for the detected streaks.

  15. Hitting Is Contagious in Baseball: Evidence from Long Hitting Streaks

    PubMed Central

    Bock, Joel R.; Maewal, Akhilesh; Gough, David A.

    2012-01-01

    Data analysis is used to test the hypothesis that hitting is contagious. A statistical model is described to study the effect of a hot hitter upon his teammates batting during a consecutive game hitting streak. Box score data for entire seasons comprising streaks of length games, including a total observations were compiled. Treatment and control sample groups () were constructed from core lineups of players on the streaking batters team. The percentile method bootstrap was used to calculate confidence intervals for statistics representing differences in the mean distributions of two batting statistics between groups. Batters in the treatment group (hot streak active) showed statistically significant improvements in hitting performance, as compared against the control. Mean for the treatment group was found to be to percentage points higher during hot streaks (mean difference increased points), while the batting heat index introduced here was observed to increase by points. For each performance statistic, the null hypothesis was rejected at the significance level. We conclude that the evidence suggests the potential existence of a statistical contagion effect. Psychological mechanisms essential to the empirical results are suggested, as several studies from the scientific literature lend credence to contagious phenomena in sports. Causal inference from these results is difficult, but we suggest and discuss several latent variables that may contribute to the observed results, and offer possible directions for future research. PMID:23251507

  16. Design and Field Test of a Galvanometer Deflected Streak Camera

    SciTech Connect

    Lai, C C; Goosman, D R; Wade, J T; Avara, R

    2002-11-08

    We have developed a compact fieldable optically-deflected streak camera first reported in the 20th HSPP Congress. Using a triggerable galvanometer that scans the optical signal, the imaging and streaking function is an all-optical process without incurring any photon-electron-photon conversion or photoelectronic deflection. As such, the achievable imaging quality is limited mainly only by optical design, rather than by multiple conversions of signal carrier and high voltage electron-optics effect. All core elements of the camera are packaged into a 12 inch x 24 inch footprint box, a size similar to that of a conventional electronic streak camera. At LLNL's Site-300 Test Site, we have conducted a Fabry-Perot interferometer measurement of fast object velocity using this all-optical camera side-by-side with an intensified electronic streak camera. These two cameras are configured as two independent instruments for recording synchronously each branch of the 50/50 splits from one incoming signal. Given the same signal characteristics, the test result has undisputedly demonstrated superior imaging performance for the all-optical streak camera. It produces higher signal sensitivity, wider linear dynamic range, better spatial contrast, finer temporal resolution, and larger data capacity as compared with that of the electronic counterpart. The camera had also demonstrated its structural robustness and functional consistence to be well compatible with field environment. This paper presents the camera design and the test results in both pictorial records and post-process graphic summaries.

  17. Barley Yellow Dwarf

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley yellow dwarf is the most economically important virus disease affecting most cereal crops world wide. This manuscript summarizes the current knowledge of the disease etiology, epidemiology and management. This information is incorporated into the latest revision of the American Phytopathologi...

  18. Attosecond Streaking Enables the Measurement of Quantum Phase

    SciTech Connect

    Yakovlev, V. S.; Gagnon, J.; Krausz, F.; Karpowicz, N.

    2010-08-13

    Attosecond streaking, as a measurement technique, was originally conceived as a means to characterize attosecond light pulses, which is a good approximation if the relevant transition matrix elements are approximately constant within the bandwidth of the light pulse. Our analysis of attosecond streaking measurements on systems with a complex response to the photoionizing pulse reveals the relation between the momentum-space wave function of the outgoing electron and the result of conventional retrieval algorithms. This finding enables the measurement of the quantum phase associated with bound-continuum transitions.

  19. A fiber sensor neutron streak camera for ICF diagnostics

    SciTech Connect

    Kislev, H.; Miley, G.H.

    1986-11-01

    The authors propose an optical sensing based neutron streak camera for ICF burn studies. The conversion of the neutron flux to optical signal is gained through measuring the time dependent optical attenuation (darkening) of a fissile material doped fiber optics. The miniature sensor enables a sensing distance of > 2 cm from the target, such that the neutron doppler broadening can be neglected. An additional major advantage over the current designs is that the streak camera is removed from the intense radiation field. Estimates of minimum yield requirements, darkening time response, and overall temporal resolution are presented.

  20. Wheat streak mosaic virus-Structural parameters for a Potyvirus

    SciTech Connect

    Parker, Lauren; Kendall, Amy; Berger, P.H.; Shiel, P.J.; Stubbs, Gerald . E-mail: gerald.stubbs@vanderbilt.edu

    2005-09-15

    Wheat streak mosaic virus is a Tritimovirus, a member of the Potyviridae family, which includes the very large Potyvirus genus. We have examined wheat streak mosaic virus by electron microscopy and fiber diffraction from partially oriented sols, and analyzed the results to estimate the symmetry and structural parameters of the viral helix. The virions have an apparent radius of 63 {+-} 5 A. The viral helix has a pitch of 33.4 A {+-} 0.6 A. There appear to be 6.9 subunits per turn of the helix, although we cannot completely eliminate values of 5.9 or 7.9 for this parameter.

  1. Mars - Wind streak production as related to obstacle type and size

    NASA Astrophysics Data System (ADS)

    Lee, S. W.

    1984-06-01

    The characteristics of wind streaks associated with Martian craters and hills in the size range of 100 m to 80 km (corresponding to obstacle heights of a few to several hundred meters) have been analyzed from Viking Orbiter images. Both dark erosional and bright depositional streaks form over the entire obstacle size range, but there are preferred obstacle sizes for producing streaks. Bright streaks form more readily in association with relatively smaller obstacles than do dark streaks. Small obstacles produce both types of streaks more effectively than do large ones. Hills produce streaks as effectively as do craters of comparable height. Alternative explanations of bright streak formation are evaluated in terms of their ability to account for these observations. The most satisfactory models invoke blocking of atmospheric flow downwind of an obstacle and consequent deposition of dust within the sheltered zone.

  2. [Yellow fever: new recommendations].

    PubMed

    Rochat, L; Genton, B

    2014-05-01

    Indication for yellow fever vaccination is not always easy to assess. The decision to immunize is not only based on the actual risk of the disease in a specific location, but also on public health considerations in the visited country (in order to respectively avoid epidemics in endemic countries or the introduction of the virus in zones where the vectors mosquitoes are present) and on travelers' risk factors for severe or even fatal vaccine adverse events. WHO has recently published new recommendations regarding vaccination against yellow fever after concluding that one dose of vaccine generates a life-long protection. This article tends to clarify the strategy to adopt in 2013 using cases frequently encountered in the practice of travel medicine. PMID:24908746

  3. The economics of vein disease.

    PubMed

    Sales, Clifford M; Podnos, Joan; Levison, Jonathan

    2007-09-01

    The management of cosmetic vein problems requires a very different approach than that for the majority of most other vascular disorders that occur in a vascular surgery practice. This article focuses on the business aspects of a cosmetic vein practice, with particular attention to the uniqueness of these issues. Managing patient expectations is critical to the success of a cosmetic vein practice. Maneuvering within the insurance can be difficult and frustrating for both the patient and the practice. Practices should use cost accounting principles to evaluate the success of their vein work. Vein surgery--especially if performed within the office--can undergo an accurate break-even analysis to determine its profitability. PMID:17911565

  4. The Management of Varicose Veins

    PubMed Central

    Lin, Fan; Zhang, Shiyi; Sun, Yan; Ren, Shiyan; Liu, Peng

    2015-01-01

    This study aimed to review the current management modalities for varicose veins. There are a variety of management modalities for varicose veins. The outcomes of the treatment of varicose veins are different. The papers on the management of varicose veins were reviewed and the postoperative complications and efficacy were compared. Foam sclerotherapy and radiofrequency ablation were associated with less pain and faster recovery than endovenous laser ablation and surgical stripping. Patients undergoing endovenous laser ablation and radiofrequency ablation are most likely to have a faster recovery time and earlier return to work in comparison with those undergoing conventional high ligation and stripping. A randomized controlled study in multiple centers is warranted to verify which approach is better than others for the treatment of varicose veins. PMID:25594661

  5. Varicose veins - what to ask your doctor

    MedlinePLUS

    ... veins do you perform? Sclerotherapy? Heat ablation or laser ablation? Vein stripping? Questions to ask about different procedures for varicose veins are: How does this treatment work? When would it be a good choice for ...

  6. Reliable and repeatable characterization of optical streak cameras.

    PubMed

    Charest, Michael R; Torres, Peter; Silbernagel, Christopher T; Kalantar, Daniel H

    2008-10-01

    Optical streak cameras are used as primary diagnostics for a wide range of physics and laser experiments at facilities such as the National Ignition Facility. To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electrical components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases, the characterization data are applied to the raw data images to correct for the nonlinearities. In order to characterize an optical streak camera, a specific set of data is collected, where the response to defined inputs are recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, and temporal resolution from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information. PMID:19044688

  7. Reliable and Repeatable Characterication of Optical Streak Cameras

    SciTech Connect

    Kalantar, D; Charest, M; Torres III, P; Charest, M

    2008-05-06

    Optical streak cameras are used as primary diagnostics for a wide range of physics and laser experiments at facilities such as the National Ignition Facility (NIF). To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electrical components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases, the characterization data are applied to the raw data images to correct for the nonlinearities. In order to characterize an optical streak camera, a specific set of data is collected, where the response to defined inputs are recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, and temporal resolution from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information.

  8. Reliable and Repeatable Characterization of Optical Streak Cameras

    SciTech Connect

    Michael Charest Jr., Peter Torres III, Christopher Silbernagel, and Daniel Kalantar

    2008-10-31

    Optical streak cameras are used as primary diagnostics for a wide range of physics and laser experiments at facilities such as the National Ignition Facility (NIF). To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electrical components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases, the characterization data are applied to the raw data images to correct for the nonlinearities. In order to characterize an optical streak camera, a specific set of data is collected, where the response to defined inputs are recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, and temporal resolution from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information.

  9. Reliable and repeatable characterization of optical streak cameras

    SciTech Connect

    Charest, Michael R. Jr.; Torres, Peter III; Silbernagel, Christopher T.; Kalantar, Daniel H.

    2008-10-15

    Optical streak cameras are used as primary diagnostics for a wide range of physics and laser experiments at facilities such as the National Ignition Facility. To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electrical components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases, the characterization data are applied to the raw data images to correct for the nonlinearities. In order to characterize an optical streak camera, a specific set of data is collected, where the response to defined inputs are recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, and temporal resolution from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information.

  10. Processing Particle-Streak Imagery On A Personal Computer

    NASA Technical Reports Server (NTRS)

    Cho, Y. C.; Mclachlan, B. G.

    1991-01-01

    Report describes simple flow experiment in which streak images of particles suspended in fluid and illuminated for short times processed into maps of velocity vectors. In experiment, semiautomatic data-reduction scheme used which recovers significant image data more efficiently than currently available automatic scheme.

  11. Improved approach to characterizing and presenting streak camera performance

    SciTech Connect

    Wiedwald, J.D.; Jones, B.A.

    1985-07-15

    The performance of a streak camera recording system is strongly linked to the technique used to amplify, detect and quantify the streaked image. At the Lawrence Livermore National Laboratory (LLNL) streak camera images have been recorded both on film and by fiber-optically coupling to charge-coupled devices (CCD's). During the development of a new process for recording these images (lens coupling the image onto a cooled CCD) the definitions of important performance characteristics such as resolution and dynamic range were re-examined. As a result of this development, these performance characteristics are now presented to the streak camera user in a more useful format than in the past. This paper describes how these techniques are used within the Laser Fusion Program at LLNL. The system resolution is presented as a modulation transfer function, including the seldom reported effects that flare and light scattering have at low spatial frequencies. Data are presented such that a user can adjust image intensifier gain and pixel averaging to optimize the useful dynamic range in any particular application.

  12. Soft x-ray streak camera for laser fusion applications

    SciTech Connect

    Stradling, G.L.

    1981-04-01

    This thesis reviews the development and significance of the soft x-ray streak camera (SXRSC) in the context of inertial confinement fusion energy development. A brief introduction of laser fusion and laser fusion diagnostics is presented. The need for a soft x-ray streak camera as a laser fusion diagnostic is shown. Basic x-ray streak camera characteristics, design, and operation are reviewed. The SXRSC design criteria, the requirement for a subkilovolt x-ray transmitting window, and the resulting camera design are explained. Theory and design of reflector-filter pair combinations for three subkilovolt channels centered at 220 eV, 460 eV, and 620 eV are also presented. Calibration experiments are explained and data showing a dynamic range of 1000 and a sweep speed of 134 psec/mm are presented. Sensitivity modifications to the soft x-ray streak camera for a high-power target shot are described. A preliminary investigation, using a stepped cathode, of the thickness dependence of the gold photocathode response is discussed. Data from a typical Argus laser gold-disk target experiment are shown.

  13. Vein matching using artificial neural network in vein authentication systems

    NASA Astrophysics Data System (ADS)

    Noori Hoshyar, Azadeh; Sulaiman, Riza

    2011-10-01

    Personal identification technology as security systems is developing rapidly. Traditional authentication modes like key; password; card are not safe enough because they could be stolen or easily forgotten. Biometric as developed technology has been applied to a wide range of systems. According to different researchers, vein biometric is a good candidate among other biometric traits such as fingerprint, hand geometry, voice, DNA and etc for authentication systems. Vein authentication systems can be designed by different methodologies. All the methodologies consist of matching stage which is too important for final verification of the system. Neural Network is an effective methodology for matching and recognizing individuals in authentication systems. Therefore, this paper explains and implements the Neural Network methodology for finger vein authentication system. Neural Network is trained in Matlab to match the vein features of authentication system. The Network simulation shows the quality of matching as 95% which is a good performance for authentication system matching.

  14. Retinal Vein Occlusion.

    PubMed

    Sawada, Osamu; Ohji, Masahito

    2016-01-01

    The primary treatment against macular edema with retinal vein occlusion (RVO) has changed from observation in central RVO (CRVO) and laser photocoagulation in branch RVO (BRVO) to administration of intravitreal agents based on anti-vascular endothelial growth factor (VEGF) or anti-inflammatory strategies. Anti-VEGF treatment such as ranibizumab, bevacizumab, or aflibercept improved vision by 13.9-16.2 letters (best-corrected visual acuity) after 12 months versus baseline in patients with macular edema secondary to CRVO. A long-term study showed that reduced follow-up and fewer retreatments resulted in worsening visual acuity. Intravitreal therapy with anti-inflammatory agents stabilized visual acuity in CRVO. However, increased intraocular pressure and cataract progression were frequently observed. Anti-VEGF agents such as ranibizumab or bevacizumab improved visual acuity by 15.5-18.3 letters in patients with macular edema secondary to BRVO after 12 months. The improved vision remained during the long-term follow-up. There was no significant difference between standard care and intravitreal triamcinolone groups in BRVO, and increased intraocular pressure and cataract progression occurred frequently in the triamcinolone group. Anti-VEGF intravitreal administration resulted in good vision in CRVO and BRVO patients and is employed as a primary therapy. Anti-VEGF therapy requires frequent observations and intravitreal injections to maintain good vision. PMID:26501219

  15. Barley yellow dwarf viruses.

    PubMed

    Miller, W A; Rasochová, L

    1997-01-01

    Barley yellow dwarf viruses represent one of the most economically important and ubiquitous groups of plant viruses. This review focuses primarily on four research areas in which progress has been most rapid. These include (a) evidence supporting reclassification of BYDVs into two genera; (b) elucidation of gene function and novel mechanisms controlling gene expression; (c) initial forays into understanding the complex interactions between BYDV virions and their aphid vectors; and (d) replication of a BYDV satellite RNA. Economic losses, symptomatology, and means of control of BYD are also discussed. PMID:15012520

  16. How Are Varicose Veins Diagnosed?

    MedlinePLUS

    ... of Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & ... a dermatologist. This type of doctor specializes in skin conditions. Physical Exam To check for varicose veins in ...

  17. Varicose veins and venous insufficiency

    MedlinePLUS

    ... Visible, swollen veins Mild swelling of feet or ankles Itching Severe symptoms include: Leg swelling Leg or ... periods Skin color changes of the legs or ankles Dry, irritated, scaly skin that can crack easily ...

  18. Varicose Veins and Venous Insufficiency

    MedlinePLUS

    ... About Us Patient Section Who Are Interventional Radiologists? Multimedia Insurance Coverage IR Treatments Abdominal aortic aneurysms Angiography ... radiology Interventional radiology case studies Developed by ACR Multimedia gallery Multimedia Archive Varicose Veins and Venous Insufficiency ...

  19. How Are Varicose Veins Treated?

    MedlinePLUS

    ... Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & Clinical ... shun) therapy uses lasers or radiowaves to create heat to close off a varicose vein. Your doctor ...

  20. Benefits of endoscopic vein harvesting.

    PubMed

    Marty, B; von Segesser, L K; Tozzi, P; Guzmann, J; Frascarolo, P; Muller, X; Hayoz, D

    2000-09-01

    The purpose of this study was to evaluate and compare the benefits of endoscopic saphenous vein harvesting (EVH) with the traditional incision technique (TIT) for coronary artery bypass grafting (CABG) in respect to the technical procedure and clinical outcome. In a prospective nonrandomized, case-matched study the greater saphenous vein was harvested for CABG in 22 patients using the endoscopic technique and in 18 patients with the traditional method. Comparisons were made for the operating time, length of incision and vein harvested, graft quality, postoperative complications, and pain assessment. Patient demographics were well matched. EVH required smaller incisions than did the TIT (10.5 +/- 6.6 vs. 31.2 +/- 7.8 cm, respectively; p < 0.0001). Harvest time and vein quality were comparable in the two groups. Total vein operating time was shorter following the endoscopic technique (60 +/- 24 vs. 100 +/- 35 minutes, respectively; p < 0.0001). EVH had fewer complications (NS), and postoperative pain was significantly less (p = 0.0034). The major advantages of endoscopic vein harvesting are a significant reduction of postoperative pain and strikingly better cosmetic results. Wound complications seem to be less frequent. PMID:11036289

  1. Timing between streak cameras with a precision of 10 ps

    SciTech Connect

    Lerche, R.A.

    1990-12-07

    The laser beams irradiating a target at the Nova laser facility comprise a set of ten simultaneous events. Two streak cameras, whose resolutions are 40 ps, record the power history for each beam, five beams to a camera; their time bases are cross-timed with a fiducial pulse. Analysis of data recorded for target experiments conducted over a six month period show the precision for cross-timing signals between two streak cameras to be {plus minus}9 ps and for characterizing a single temporal feature of a pulse to be {plus minus}5 ps. Beam synchronization at the end of six months was within 20 ps of the synchronization at the beginning of the experiments. A beam timing shift greater than 25 ps can be detected on a single laser shot; shifts of 10 to 20 ps require several shots to detect. 2 refs., 6 figs.

  2. Circular-scan streak tube with solid-state readout

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Nevin, S.; Bebris, J.; Abshire, J. B.

    1980-01-01

    A circular-scan streak tube designed for use in a laser ranging system is described. Electrostatic focusing is used between the photocathode and a microchannel plate, and electrons from the microchannel plate are proximity focused onto an output phosphor screen. Electron beam deflection is achieved by driving two orthogonal sets of deflection plate assemblies in phase quadrature at a frequency of 200 MHz. The light intensity in the output beam trace is measured by using a circular Reticon array of 720 photodiodes, which is fiber-optically coupled to the output phosphor screen of the tube. Sample measurements of frequency-doubled Nd:YAG laser-pulse waveforms are given. Also the output beamwidth has been measured at the 200-MHz deflection frequency. The results suggest a limiting resolution of 33 psec for the circular-scan streak tube used for these tests.

  3. Modeling and detecting potentially ruinous streaks in health expenditures.

    PubMed

    Koopmeiners, Joseph S; Dowd, Bryan E; Carlin, Bradley P

    2007-03-01

    The mean of a distribution of medical expenditures in an insured population can be affected significantly by the occurrence of a few high cost cases. This fact leads some organizations that hold the primary risk for the population (e.g., health plans or self-insured employers) to seek reinsurance arrangements that spread the risk of high cost cases across a broader pool. Recently, the private reinsurance market has experienced some difficulties, attributable to information asymmetries between primary risk holders and reinsurers. The disproportionate effect of a few high cost cases also has generated interest in the development of "risk-adjustment" systems that attempt to reduce the difference in health plans' unreimbursed costs either to endogenous management decisions or random chance. We discuss these issues in light of a well-known statistical result regarding the probability of "streaks" in random data. We illustrate problems that can arise and suggest methods to distinguish random streaks from systematic trends. PMID:17351750

  4. Banana streak virus is very diverse in Uganda.

    PubMed

    Harper, Glyn; Hart, Darren; Moult, Sarah; Hull, Roger

    2004-03-01

    Banana streak virus (BSV) is a badnavirus that causes a viral leaf streak disease of banana and plantain (Musa spp.). Identified in essentially all Musa growing areas of the world, it has a deleterious effect on the productivity of infected plants as well as being a major constraint to Musa breeding programmes and germplasm dissemination. Banana is a staple food in Uganda which is, per capita, one of the worlds largest banana producers and consumers. BSV was isolated from infected plants sampled across the Ugandan Musa growing area and the isolates were analysed using molecular and serological techniques. These analyses showed that BSV is very highly variable in Uganda. They suggest that the variability is, in part, due to a series of introductions of banana into Uganda, each with a different complement of infecting viruses. PMID:15036835

  5. Megahertz streak-mode Fourier domain optical coherence tomography.

    PubMed

    Wang, Rui; Yun, Julie X; Yuan, Xiaocong; Goodwin, Richard; Markwald, Roger R; Gao, Bruce Z

    2011-06-01

    Here we present an ultrahigh-speed Fourier-domain optical coherence tomography (OCT) that records the OCT spectrum in streak mode with a high-speed area scan camera, which allows higher OCT imaging speed than can be achieved with a line-scan camera. Unlike parallel OCT techniques that also use area scan cameras, the conventional single-mode fiber-based point-scanning mechanism is retained to provide a confocal gate that rejects multiply scattered photons from the sample. When using a 1000 Hz resonant scanner as the streak scanner, 1,016,000 A-scans have been obtained in 1 s. This method's effectiveness has been demonstrated by recording in vivo OCT-image sequences of embryonic chick hearts at 1000 frames/s. In addition, 2-megahertz OCT data have been obtained with another high speed camera. PMID:21721817

  6. Reinforcement of steady streaks for consecutive transition delay

    NASA Astrophysics Data System (ADS)

    Sattarzadeh, Sohrab S.; Fransson, Jens H. M.

    2015-03-01

    Miniature vortex genrators (MVGs) are recently proven efficient as passive control devices to delay the turbulence transition on a flat plate boundary layer by modulating the base flow in the spanwise direction, through generating steady streamwise elongated streaks, and hence reducing the skin-friction drag. As the MVGs are localized in the streamwise direction, a shortcoming of the passive laminar control is the recovery of the two-dimensional boundary layer which force the control effects to fade away. In the present study we show that by placing a second array of MVGs downstream of the first one the streamwise extent of the control can be prolonged by reinforcing the steady streaks in the streamwise direction. The reinforced passive control strategy results in consecutive turbulence transition delay with obtaining a net skin-friction drag reduction of 65 %, for the present measurement conditions, compared to the smooth plate boundary layer. Support from the European Research Council (ERC) is acknowledged.

  7. 9. VIEW OF 'BLUE STREAK' HAMMER MILL (Prater Pulverizer Co., ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF 'BLUE STREAK' HAMMER MILL (Prater Pulverizer Co., Chicago, Illinois), LOCATED IN THE SOUTHEAST CORNER OF THE BASEMENT, WAS ADDED IN THE EARLY 1930s. THIS WAS THE MILL'S FIRST ELECTRIC-POWERED MACHINERY. THE HAMMER MILL WAS USED TO PULVERIZE OATS, ALFALFA MEAL, AND CORN. Photographer: Louise Taft Cawood, July 1986 - Alexander's Grist Mill, Lock 37 on Ohio & Erie Canal, South of Cleveland, Valley View, Cuyahoga County, OH

  8. Slope Streaks in the Antarctic Dry Valleys: Characteristics, Candidate Formation Mechanisms, and Implications for Slope Streak Formation in the Martian Environment

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Marchant, D. R.; Dickson, J. L.; Levy, J. S.; Morgan, G. A.

    2007-03-01

    Mars slope streaks are thought to have formed by dry dust avalanches; slope streaks in the Mars-like ADV form by melting of surface/shallow subsurface snow/ice, meltwater migration along the top of the ice table, and wicking to form surface wetting.

  9. Yellow fever vaccine

    PubMed Central

    Verma, Ramesh; Khanna, Pardeep; Chawla, Suraj

    2014-01-01

    Yellow fever (YF) is an acute viral communicable disease transmitted by an arbovirus of the Flavivirus genus. It is primarily a zoonotic disease, especially the monkeys. Worldwide, an estimated 200 000 cases of yellow fever occurred each year, and the case-fatality rate is ~15%. Forty-five endemic countries in Africa and Latin America, with a population of close to 1 billion, are at risk. Up to 50% of severely affected persons from YF die without treatment. During 2009, 55 cases and 18 deaths were reported from Brazil, Colombia, and Peru. Brazil reported the maximum number of cases and death, i.e., 42 cases with 11 deaths. From January 2010 to March 2011, outbreaks of YF were reported to the WHO by Cameroon, Democratic Republic of Congo, Cote d’Ivoire, Guinea, Sierra Leone, Senegal, and Uganda. Cases were also reported in three northern districts of Abim, Agago, and Kitugun near the border with South Sudan. YF usually causes fever, muscle pain with prominent backache, headache, shivers, loss of appetite, and nausea or vomiting. Most patients improve, and their symptoms disappear after 3 to 4 d. Half of the patients who enter the toxic phase die within 10–14 d, while the rest recover without significant organ damage. Vaccination has been the single most important measure for preventing YF. The 17D-204 YF vaccine is a freeze-dried, live attenuated, highly effective vaccine. It is available in single-dose or multi-dose vials and should be stored at 2–8 °C. It is reconstituted with normal saline and should be used within 1 h of reconstitution. The 0.5 mL dose is delivered subcutaneously. Revaccination is recommended every 10 y for people at continued risk of exposure to yellow fever virus (YFV). This vaccine is available worldwide. Travelers, especially to Africa or Latin America from Asia, must have a certificate documenting YF vaccination, which is required by certain countries for entry under the International Health Regulations (IHR) of the WHO. PMID:24056028

  10. Reliable and Repeatable Characterization of Optical Streak Cameras

    SciTech Connect

    Michael R. Charest, Peter Torres III, Christopher Silbernagel

    2008-03-01

    Optical streak cameras are used as primary diagnostics for a wide range of physics and laser performance verification experiments at the National Ignition Facility (NIF). To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electronic components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases the characterization data is used to correct data images, to remove some of the nonlinearities. In order to obtain these camera characterizations, a specific data set is collected where the response to specific known inputs is recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, temporal resolution, etc., from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information.

  11. Design of microcontroller based system for automation of streak camera

    SciTech Connect

    Joshi, M. J.; Upadhyay, J.; Deshpande, P. P.; Sharma, M. L.; Navathe, C. P.

    2010-08-15

    A microcontroller based system has been developed for automation of the S-20 optical streak camera, which is used as a diagnostic tool to measure ultrafast light phenomenon. An 8 bit MCS family microcontroller is employed to generate all control signals for the streak camera. All biasing voltages required for various electrodes of the tubes are generated using dc-to-dc converters. A high voltage ramp signal is generated through a step generator unit followed by an integrator circuit and is applied to the camera's deflecting plates. The slope of the ramp can be changed by varying values of the capacitor and inductor. A programmable digital delay generator has been developed for synchronization of ramp signal with the optical signal. An independent hardwired interlock circuit has been developed for machine safety. A LABVIEW based graphical user interface has been developed which enables the user to program the settings of the camera and capture the image. The image is displayed with intensity profiles along horizontal and vertical axes. The streak camera was calibrated using nanosecond and femtosecond lasers.

  12. Slope streaks on Mars: A new wet mechanism

    NASA Astrophysics Data System (ADS)

    Kreslavsky, Mikhail A.; Head, James W.

    2009-06-01

    Slope steaks are one of the most intriguing modern phenomena observed on Mars. They have been mostly interpreted as some specific type of granular flow. We propose another mechanism for slope streak formation on Mars. It involves natural seasonal formation of a modest amount of highly concentrated chloride brines within a seasonal thermal skin, and runaway propagation of percolation fronts. Given the current state of knowledge of temperature regimes and the composition and structure of the surface layer in the slope streak regions, this mechanism is consistent with the observational constraints; it requires an assumption that a significant part of the observed chlorine to be in form of calcium and ferric chloride, and a small part of the observed hydrogen to be in form of water ice. This "wet" mechanism has a number of appealing advantages in comparison to the widely accepted "dry" granular flow mechanism. Potential tests for the "wet" mechanism include better modeling of the temperature regime and observations of the seasonality of streak formation.

  13. Infrared imagery of streak formation in a breaking wave

    NASA Astrophysics Data System (ADS)

    Handler, Robert A.; Savelyev, Ivan; Lindsey, Michael

    2012-12-01

    High resolution infrared imagery of breaking waves in a wave-tank free of wind shear or current reveals the production of a "streaky," quasi-periodic thermal pattern produced during the breaking process. The streaks, or elongated patterns of warm and cold fluid, are found to form only when surface turbulence is present before wave breaking occurs. This suggests that wave-turbulence interaction is one mechanism that can lead to streak formation in breaking wave systems. More specifically, the streaky structures observed in these experiments may be caused by an intense, rapid tilting, and stretching of pre-existing vertical vorticity by the Stokes drift generated at or near the breaking wave crests, thereby generating a coherent system of counter-rotating vortices. We attempt to relate our observations to the recent theory of Teixeira and Belcher [J. Fluid Mech. 458, 229-267 (2002), 10.1017/S0022112002007838]. Some properties of the streaks, such as the dependence of their lifetimes and spanwise scale on wave amplitude, are presented.

  14. Streaking at high energies with electrons and positrons

    SciTech Connect

    Ipp, Andreas; Evers, Joerg; Keitel, Christoph H.; Hatsagortsyan, Karen Z.

    2012-07-09

    State-of-the-art attosecond metrology deals with the detection and characterization of photon pulses with typical energies up to the hundreds of eV and time resolution of several tens of attoseconds. Such short pulses are used for example to control the motion of electrons on the atomic scale or to measure inner-shell atomic dynamics. The next challenge of time-resolving the inner-nuclear dynamics, transient meson states and resonances requires photon pulses below attosecond duration and with energies exceeding the MeV scale. Here we discuss a detection scheme for time-resolving high-energy gamma ray pulses down to the zeptosecond timescale. The scheme is based on the concept of attosecond streak imaging, but instead of conversion of photons into electrons in a nonlinear medium, the high-energy process of electron-positron pair creation is utilized. These pairs are produced in vacuum through the collision of a test pulse to be characterized with an intense laser pulse, and they acquire additional energy and momentum depending on their phase in the streaking pulse at the moment of production. A coincidence measurement of the electron and positron momenta after the interaction provides information on the pair production phase within the streaking pulse. We examine the limitations imposed by quantum radiation reaction in multiphoton Compton scattering on this detection scheme, and discuss other necessary conditions to render the scheme feasible in the upcoming Extreme Light Infrastructure (ELI) laser facility.

  15. Design of microcontroller based system for automation of streak camera

    NASA Astrophysics Data System (ADS)

    Joshi, M. J.; Upadhyay, J.; Deshpande, P. P.; Sharma, M. L.; Navathe, C. P.

    2010-08-01

    A microcontroller based system has been developed for automation of the S-20 optical streak camera, which is used as a diagnostic tool to measure ultrafast light phenomenon. An 8 bit MCS family microcontroller is employed to generate all control signals for the streak camera. All biasing voltages required for various electrodes of the tubes are generated using dc-to-dc converters. A high voltage ramp signal is generated through a step generator unit followed by an integrator circuit and is applied to the camera's deflecting plates. The slope of the ramp can be changed by varying values of the capacitor and inductor. A programmable digital delay generator has been developed for synchronization of ramp signal with the optical signal. An independent hardwired interlock circuit has been developed for machine safety. A LABVIEW based graphical user interface has been developed which enables the user to program the settings of the camera and capture the image. The image is displayed with intensity profiles along horizontal and vertical axes. The streak camera was calibrated using nanosecond and femtosecond lasers.

  16. A new design of filter system in streak camera

    NASA Astrophysics Data System (ADS)

    Zhou, Pengyu; Bai, Yonglin

    2015-10-01

    In order to reduce the frequency of researchers routing in and out of the testing site and ensure the fluency of the testing we design a new filter system applied to the streak cameras. This system promotes streak cameras' abilities on spatial discrimination and time resolution. This paper focuses on the instruction of the piezoelectric motor's principle based on field-effect tubes. Filter wheel is driven by piezoelectric motor. It can effectively avoid the influences of high field produced by streak tube. Finally we achieve auto regulation at different gears and promote the efficiency of operations and guarantee the safety of researchers. CD4046 introduces the driven clock of this system and we use an inverter to get two synchronous inverted signals. These signals are amplified by field-effect tubes to more than 300V. The amplified ones are integrated at the output terminals to generate sinusoidal signal. The test shows that in this filter system piezoelectric motor operates at its resonance frequency under a control signal of 62.5 KHz. Its working current is 1.9A and driving power is almost 10W. By adjusting the gears, the filter wheel costs less than 2 seconds to calibrate. We accomplish the test in respected results.

  17. Design of microcontroller based system for automation of streak camera.

    PubMed

    Joshi, M J; Upadhyay, J; Deshpande, P P; Sharma, M L; Navathe, C P

    2010-08-01

    A microcontroller based system has been developed for automation of the S-20 optical streak camera, which is used as a diagnostic tool to measure ultrafast light phenomenon. An 8 bit MCS family microcontroller is employed to generate all control signals for the streak camera. All biasing voltages required for various electrodes of the tubes are generated using dc-to-dc converters. A high voltage ramp signal is generated through a step generator unit followed by an integrator circuit and is applied to the camera's deflecting plates. The slope of the ramp can be changed by varying values of the capacitor and inductor. A programmable digital delay generator has been developed for synchronization of ramp signal with the optical signal. An independent hardwired interlock circuit has been developed for machine safety. A LABVIEW based graphical user interface has been developed which enables the user to program the settings of the camera and capture the image. The image is displayed with intensity profiles along horizontal and vertical axes. The streak camera was calibrated using nanosecond and femtosecond lasers. PMID:20815627

  18. Yellow intraocular filters in fishes.

    PubMed

    Heinermann, P H

    1984-01-01

    Yellow intraocular filters are common among the teleosts, especially highly diurnal species. This yellow pigmentation may be uniform, more dense dorsally, or localized to a narrow dorsal ring near the limbus. Certain species possess occlusable yellow corneas and can vary the corneal colour in response to the level of illumination. Yellow lenses and corneas function as hi-pass filters, with the cutoff points varying depending on species. Thus, the amount of short-wavelength light reaching the retina can be regulated. Three distinct yellow pigments may be present in each of the lens, cornea and the retina of certain South American cichlids. The spectral absorbance of the yellow corneal pigment bears a close resemblance to that of beta-carotene. Possible functions of these yellow filters are: a reduction in chromatic aberration, the reduction of glare and dazzle, the improvement of detail by the absorption of "blue haze", the improvement of contrast vision, and the rendering of bioluminescence more conspicuous. Yellow intraocular filters may result in a loss of scotopic sensitivity due to absorption of short wavelengths. Various adaptations in diurnal teleosts to avoid the loss of sensitivity resulting from a yellow filter are presented. Normally, bottom-dwelling fishes lack yellow filters. These filters cause the effective absorbance maximum of scotopic visual pigments to be shifted to longer wavelengths. No correlation has been found between the presence of such filters and the water colour, diet or spectral absorbance of the visual pigment. A possible explanation for the lack of correlation with visual pigments is discussed. Investigation of cone spectral sensitivities may possibly reveal such a correlation. PMID:6398222

  19. Cell streak imaging cytometry for rare cell detection

    PubMed Central

    Balsam, Joshua; Bruck, Hugh Alan; Rasooly, Avraham

    2014-01-01

    Detection of rare cells, such as circulating tumor cells, have many clinical applications. To measure rare cells with increased sensitivity and improved data managements, we developed an imaging flow cytometer with a streak imaging mode capability. The new streak mode imaging mode utilizes low speed video to capture moving fluorescently labeled cells in a flow cell. Each moving cell is imaged on multiple pixels on each frame, where the cell path is marked as a streak line proportional to the length of the exposure. Finding rare cells (e.g., <1 cell/mL) requires measuring larger sample volumes to achieve higher sensitivity, therefore we combined streak mode imaging with a wide high throughput flow cell (e.g. flow rates set to 10 mL/min) in contrast to the conventional narrow hydrodynamic focusing cells typically used in cytometry that are inherently limited to low flow rates. The new flow cell is capable of analyzing 20 mL/min of fluorescently labeled cells. To further increase sensitivity, the signal to noise ratio of the images was also enhanced by combining three imaging methods: (1) background subtraction, (2) pixel binning, and (3) CMOS color channel selection. The streaking mode cytometer has been used for the analysis of SYTO-9 labeled THP-1 human monocytes in buffer and in blood. Samples of cells at 1 cell/mL and 0.1 cell/mL were analyzed in 30 mL with flow rates set to 10 mL/min and frame rates of 4 fps (frame per second). For the target of 1 cell/mL, an average concentration of 0.91 cell/mL was measured by cytometry, with a standard error of 0.03 (C95 = 0.850.97). For the target of 0.1 cell/mL, an average concentration of 0.083 cell/mL was measured, with a standard error of 0.01 (C95 = 0.0650.102). Whole blood was also spiked with SYTO-9 labeled cells to a concentration of 10 cell/mL, and the average flow cytometry measurement was 8.7 cells/mL (i.e. 0.87 cells/mL in diluted blood) with a 95% CL of 8.19.2 cells/mL. This demonstrated the ability to detect rare cells in blood with high accuracy. Such detection approaches for rare cells have many potential clinical applications. Furthermore, the simplicity and low cost of this device may enable expansion of cell-based clinical diagnostics, especially in resource-poor settings. PMID:25212069

  20. Streak camera based SLR receiver for two color atmospheric measurements

    NASA Technical Reports Server (NTRS)

    Varghese, Thomas K.; Clarke, Christopher; Oldham, Thomas; Selden, Michael

    1993-01-01

    To realize accurate two-color differential measurements, an image digitizing system with variable spatial resolution was designed, built, and integrated to a photon-counting picosecond streak camera, yielding a temporal scan resolution better than 300 femtosecond/pixel. The streak camera is configured to operate with 3 spatial channels; two of these support green (532 nm) and uv (355 nm) while the third accommodates reference pulses (764 nm) for real-time calibration. Critical parameters affecting differential timing accuracy such as pulse width and shape, number of received photons, streak camera/imaging system nonlinearities, dynamic range, and noise characteristics were investigated to optimize the system for accurate differential delay measurements. The streak camera output image consists of three image fields, each field is 1024 pixels along the time axis and 16 pixels across the spatial axis. Each of the image fields may be independently positioned across the spatial axis. Two of the image fields are used for the two wavelengths used in the experiment; the third window measures the temporal separation of a pair of diode laser pulses which verify the streak camera sweep speed for each data frame. The sum of the 16 pixel intensities across each of the 1024 temporal positions for the three data windows is used to extract the three waveforms. The waveform data is processed using an iterative three-point running average filter (10 to 30 iterations are used) to remove high-frequency structure. The pulse pair separations are determined using the half-max and centroid type analysis. Rigorous experimental verification has demonstrated that this simplified process provides the best measurement accuracy. To calibrate the receiver system sweep, two laser pulses with precisely known temporal separation are scanned along the full length of the sweep axis. The experimental measurements are then modeled using polynomial regression to obtain a best fit to the data. Data aggregation using normal point approach has provided accurate data fitting techniques and is found to be much more convenient than using the full rate single shot data. The systematic errors from this model have been found to be less than 3 ps for normal points.

  1. Management of superficial vein thrombosis.

    PubMed

    Cosmi, B

    2015-07-01

    Superficial vein thrombosis (SVT) is less well studied than deep vein thrombosis (DVT), because it has been considered to be a minor, self-limiting disease that is easily diagnosed on clinical grounds and that requires only symptomatic relief. The most frequently involved sites of the superficial vein system are the lower limbs, especially the saphenous veins, mostly in relation to varicosities. Lower-limb SVT shares the same risk factors as DVT; it can propagate into the deep veins, and have a complicated course with pulmonary embolism. Clinical diagnosis may not be accurate, and ultrasonography is currently indicated for both confirmation and evaluation of SVT extension. Treatment aims are symptom relief and prevention of venous thromboembolism (VTE) in relation to the thrombotic burden. SVT of the long saphenous vein within 3cm of the saphenofemoral junction (SFJ) is considered to be equivalent to a DVT, and thus deserving of therapeutic anticoagulation. Less severe forms of lower-limb SVT not involving the SFJ have been included in randomized clinical trials of surgery, compression hosiery, non-steroidal anti-inflammatory drugs, unfractionated heparin, and low molecular weight heparins, with inconclusive results. The largest randomized clinical trial available, on 3004 patients with lower-limb SVT not involving the SFJ, showed that fondaparinux 2.5mg once daily for 6weeks is more effective than placebo in reducing the risk of the composite of death from any cause and symptomatic VTE (0.9% versus 5.9%). Further studies are needed to define the optimal management strategies for SVT of the lower limbs and other sites, such as the upper limbs. PMID:25903684

  2. Portal vein thrombosis in cirrhosis.

    PubMed

    Raja, Kaiser; Jacob, Mathew; Asthana, Sonal

    2014-12-01

    Portal vein thrombosis (PVT) is being increasingly recognized in patients with advanced cirrhosis and in those undergoing liver transplantation. Reduced flow in the portal vein is probably responsible for clotting in the spleno-porto-mesenteric venous system. There is also increasing evidence that hypercoagulability occurs in advanced liver disease and contributes to the risk of PVT. Ultrasound based studies have reported a prevalence of PVT in 10-25% of cirrhotic patients without hepatocellular carcinoma. Partial thrombosis of the portal vein is more common and may not have pathophysiological consequences. However, there is high risk of progression of partial PVT to complete PVT that may cause exacerbation of portal hypertension and progression of liver insufficiency. It is thus, essential to accurately diagnose and stage PVT in patients waiting for transplantation and consider anticoagulation therapy. Therapy with low molecular weight heparin and vitamin K antagonists has been shown to achieve complete and partial recanalization in 33-45% and 15-35% of cases respectively. There are however, no guidelines to help determine the dose and therapeutic efficacy of anticoagulation in patients with cirrhosis. Anticoagulation therapy related bleeding is the most feared complication but it appears that the risk of variceal bleeding is more likely to be dependent on portal pressure rather than solely related to coagulation status. TIPS has also been reported to restore patency of the portal vein. Patients with complete PVT currently do not form an absolute contraindication for liver transplantation. Thrombectomy or thromboendovenectomy is possible in more than 75% of patients followed by anatomical end-to-end portal anastomosis. When patency of the portal vein and/or superior mesenteric vein is not achieved, only non-anatomical techniques (reno-portal anastomosis or cavo-portal hemitransposition) can be performed. These techniques, which do not fully reverse portal hypertension, are associated with higher morbidity and mortality risks in the short term. PMID:25755579

  3. Density-driven spontaneous streak segregation patterns in a thin rotating drum.

    PubMed

    Liao, C C; Hsiau, S S; Nien, H C

    2014-06-01

    Granular mixtures may segregate because of external driving forces, which play an important role in industry and geophysics. We investigate experimentally the mechanism of density-driven spontaneous streak segregation patterns in a thin rotating drum. We find that a spontaneous streak segregation pattern can occur in such a system, which we call a D-system. A phase diagram identifies three segregation pattern regimes in this study: the mixing regime, the core segregation regime, and the streak segregation regime. PMID:25019767

  4. Density-driven spontaneous streak segregation patterns in a thin rotating drum

    NASA Astrophysics Data System (ADS)

    Liao, C. C.; Hsiau, S. S.; Nien, H. C.

    2014-06-01

    Granular mixtures may segregate because of external driving forces, which play an important role in industry and geophysics. We investigate experimentally the mechanism of density-driven spontaneous streak segregation patterns in a thin rotating drum. We find that a spontaneous streak segregation pattern can occur in such a system, which we call a D-system. A phase diagram identifies three segregation pattern regimes in this study: the mixing regime, the core segregation regime, and the streak segregation regime.

  5. Modeling Gastrulation in the Chick Embryo: Formation of the Primitive Streak

    PubMed Central

    Vasiev, Bakhtier; Balter, Ariel; Chaplain, Mark; Glazier, James A.; Weijer, Cornelis J.

    2010-01-01

    The body plan of all higher organisms develops during gastrulation. Gastrulation results from the integration of cell proliferation, differentiation and migration of thousands of cells. In the chick embryo gastrulation starts with the formation of the primitive streak, the site of invagination of mesoderm and endoderm cells, from cells overlaying Koller's Sickle. Streak formation is associated with large-scale cell flows that carry the mesoderm cells overlying Koller's sickle into the central midline region of the embryo. We use multi-cell computer simulations to investigate possible mechanisms underlying the formation of the primitive streak in the chick embryo. Our simulations suggest that the formation of the primitive streak employs chemotactic movement of a subpopulation of streak cells, as well as differential adhesion between the mesoderm cells and the other cells in the epiblast. Both chemo-attraction and chemo-repulsion between various combinations of cell types can create a streak. However, only one combination successfully reproduces experimental observations of the manner in which two streaks in the same embryo interact. This finding supports a mechanism in which streak tip cells produce a diffusible morphogen which repels cells in the surrounding epiblast. On the other hand, chemotactic interaction alone does not reproduce the experimental observation that the large-scale vortical cell flows develop simultaneously with streak initiation. In our model the formation of large scale cell flows requires an additional mechanism that coordinates and aligns the motion of neighboring cells. PMID:20485500

  6. Characteristics of a streak disturbance induced by an isolated roughness element

    NASA Astrophysics Data System (ADS)

    Bade, Kyle; Naguib, Ahmed

    2012-11-01

    A detailed description of a streak disturbance introduced in a Blasius boundary layer by an isolated roughness element will be presented. This work is motivated by the desire to understand the dependence of the evolution/instability of streamwise-oriented streaks (which play a key role in bypass transition) on the method by which they are generated. The proper scaling of the streamwise evolution of the streak disturbance energy is examined. This expands upon established Rek2scaling (White et al., Physics of Fluids, 2005) of streak disturbances induced by spanwise-periodic roughness element arrays. Examining different roughness heights, k, and employing a method that accounts for the streamwise growth of the streak's wall-normal and spanwise scales, it is found that the streak energy density scales with Rek7/ 3 , in the case of an isolated roughness element. The data used in the analysis are acquired using hotwire anemometry throughout a three-dimensional domain located downstream of a single cylindrical roughness element. These measurements are complemented by smokewire visualizations, which capture clearly three distinct disturbance states, dependent upon roughness element height; namely, stable streaks, streaks with intermittent turbulent bursts, and turbulent disturbances. Correspondence is established between these states and the streamwise evolution of the streak energy and the cross-stream disturbance profiles. NSF Grant: CMMI 0932546.

  7. Turnip Yellow Mosaic Virus

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The bumpy exterior of the turnip yellow mosaic virus (TYMV) protein coat, or capsid, was defined in detail by Dr. Alexander McPherson of the University of California, Irvin using proteins crystallized in space for analysis on Earth. TYMV is an icosahedral virus constructed from 180 copies of the same protein arranged into 12 clusters of five proteins (pentamers), and 20 clusters of six proteins (hexamers). The final TYMV structure led to the unexpected hypothesis that the virus releases its RNA by essentially chemical-mechanical means. Most viruses have fairly flat coats, but in TYNV, the fold in each protein, called the jellyroll, is clustered at the points where the protein pentamers and hexamers join. The jellyrolls are almost standing on end, producing a bumpy surface with knobs at all of the pentamers and hexamers. At the inside surface of the pentamers is a void that is not present at the hexamers. The coating had been seen in early stuties of TYMV, but McPherson's atomic structure shows much more detail. The inside surface is strikingly, and unexpectedly, different than the outside. While the pentamers contain a central void on the inside, the hexameric units contain peptides linked to each other, forming a ring or, more accurately, rings to fill the void. Credit: Dr. Alexander McPherson, University of California, Irvine

  8. Defrosting Polar Dunes--Dark Spots and Wind Streaks

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The first time that the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)team saw dark spots on defrosting dune surfaces was in August and September of 1998. At that time, it was the north polar seasonal frost cap that was subliming away (more recent images from 1999 have shown the south polar frosts). This picture (above) shows a small portion of the giant dune field that surrounds the north polar region, as it appeared on August 23, 1998. At the time, it was early northern spring and the dunes were still covered with winter frost.

    Dark spots had appeared on the north polar dunes, and many of them exhibited a radial or semi-radial pattern of dark streaks and streamers. At first, there was speculation that the streaks indicated that the defrosting process might somehow involve explosions! The dark spots seemed to resemble small craters with dark, radial ejecta. It seemed possible that frozen carbon dioxide trapped beneath water ice might somehow heat up, turn to gas, expand, and then 'explode' in either a small blast or at least a 'puff' of air similar to that which comes from the blowhole of a surfacing whale or seal.

    The image shown here changed the earlier impression. The dark spots and streaks do not result from explosions. The spots--though not well understood--represent the earliest stages of defrosting on the sand dunes. The streaks, instead of being caused by small explosions, are instead the result of wind. In this picture, the fine, dark streaks show essentially identical orientations from spot to spot (e.g., compare the spots seen in boxes (a) and (b)). Each ray of dark material must result from wind blowing from a particular direction--for example, all of the spots in this picture exhibit a ray that points toward the upper left corner of the image, and each of these rays indicates the same wind regime. Each spot also has a ray pointing toward the lower right and top/upper-right. These, too, must indicate periods when the wind was strong enough to move materials, consistently, in only one direction.

    The sand that makes up the north polar dunes is dark. Each spot and streak is composed of the dune sand. The bright surfaces are all covered with frost. This picture is located near 76.9oN, 271.2oW, in the north polar sand sea. Illumination is from the lower left. The 200 meter scale also indicates a distance of 656 feet.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  9. KP-PJX-A Streaked Imager Based on a Versatile X-Ray Microscope Coupled to a High-Current Streak Tube

    SciTech Connect

    Gotchev, O V; Jaanimagi, P A; Knauer, J P; Marshall, F J; Meyerhofer, D D

    2004-10-19

    A re-entrant, highly adaptable, x-ray streaked imager has been developed for OMEGA to increase the sensitivity and spatial resolution in hydrodynamic-stability experiments. It is based on a four-mirror Kirkpatrick-Baez (KB) microscope, coupled to a high-current PJX streak tube. The unique mechanical assembly of the KB optic allows a choice between single- or multi-image modes and one- or two-dimensional imaging. Some important features of the PJX streak tube are described.

  10. Ultrashort pulse characterization with a terahertz streak camera.

    PubMed

    Schubert, O; Riek, C; Junginger, F; Sell, A; Leitenstorfer, A; Huber, R

    2011-11-15

    A phase-locked terahertz transient is exploited as an ultrafast phase gate for femtosecond optical pulses. We directly map out the group delay dispersion of a low-power near-infrared pulse by measuring the electro-optically induced polarization rotation as a function of wavelength. Our experiment covers the spectral window from 1.0 to 1.4 ?m and reaches a temporal precision better than 1 fs. A quantitative analysis of the detector response confirms that this streaking technique requires no reconstruction algorithm and is also well suited for the characterization of pulses spanning more than one optical octave. PMID:22089596

  11. Quartz Vein in the Gunsight Formation

    USGS Multimedia Gallery

    Quartz vein in biotite-rich rock in the Gunsight Formation of the Mesoproterozoic Lemhi Group. Bluish green copper-bearing minerals coat the quartz vein. Pale pinkish cobalt bloom and white caliche coat adjacent biotite-rich wallrock....

  12. Who Is at Risk for Varicose Veins?

    MedlinePLUS

    ... fetus puts pressure on the veins in the mother's legs. Varicose veins that occur during pregnancy usually get better within 3 to 12 months of delivery. Overweight or Obesity Being overweight or obese can put extra pressure ...

  13. Surgical Access to Jejunal Veins for Local Thrombolysis and Stent Placement in Portal Vein Thrombosis

    SciTech Connect

    Schellhammer, Frank; Esch, Jan Schulte am; Hammerschlag, Sascha; Knoefel, Wolfram Trudo; Fuerst, Guenter

    2008-07-15

    Portal vein thrombosis is an infrequent entity, which may cause high morbidity and mortality. We report a case of portal vein thrombosis due to benign stenosis following partial pancreatoduodenectomy with segmental replacement of the portal vein by a Gore-tex graft. Using a surgical access to jenunal veins, local thrombolysis, mechanical fragmentation of thrombus, and stent placement were successfully performed.

  14. phenoVein-A Tool for Leaf Vein Segmentation and Analysis.

    PubMed

    Bhler, Jonas; Rishmawi, Louai; Pflugfelder, Daniel; Huber, Gregor; Scharr, Hanno; Hlskamp, Martin; Koornneef, Maarten; Schurr, Ulrich; Jahnke, Siegfried

    2015-12-01

    Precise measurements of leaf vein traits are an important aspect of plant phenotyping for ecological and genetic research. Here, we present a powerful and user-friendly image analysis tool named phenoVein. It is dedicated to automated segmenting and analyzing of leaf veins in images acquired with different imaging modalities (microscope, macrophotography, etc.), including options for comfortable manual correction. Advanced image filtering emphasizes veins from the background and compensates for local brightness inhomogeneities. The most important traits being calculated are total vein length, vein density, piecewise vein lengths and widths, areole area, and skeleton graph statistics, like the number of branching or ending points. For the determination of vein widths, a model-based vein edge estimation approach has been implemented. Validation was performed for the measurement of vein length, vein width, and vein density of Arabidopsis (Arabidopsis thaliana), proving the reliability of phenoVein. We demonstrate the power of phenoVein on a set of previously described vein structure mutants of Arabidopsis (hemivenata, ondulata3, and asymmetric leaves2-101) compared with wild-type accessions Columbia-0 and Landsberg erecta-0. phenoVein is freely available as open-source software. PMID:26468519

  15. Yellow fever in the Americas.

    PubMed

    1985-01-01

    In 1983 the total number of jungle yellow fever cases in the Americas was one of the lowest in recent years. There were 2 outstanding occurrences during the year, representing the end of an epidemic that had taken place in the Santa Cruz region of Bolivia in 1981 and 1982. The small number of cases, in contrast with previous epidemics, was the result of an increasing number of vaccinations in the affected regions. At a Pan American Health Organization Seminar on the treatment and laboratory diagnosis of yellow fever held in Brazil in 1984, participants reviewed the epidemiologic situation in places where yellow fever poses a serious and ongoing public health problem. At this time, the general yellow fever situation in each of the affected countries of the Americas--Bolivia, Brazil, Colombia, Ecuador, and Peru--is as follows. Yellow fever is endemic in 2/3 of Bolivia, primarily in the south. Males are affected more often (78%) than females (22%). Generally, the patients are adults, but during a recent epidemic in the Rincon del Tigre area 14.5% of the cases occurred in children under age 4 and 11.6% in children 5-9 years. In Brazil, the endemic zone comprises states in the northern, central, and western regions and also in the western strips of the State of Maranhao. The disease occurs rarely among children under age 11, and 70% of the victims are men ranging in age from 15-40 years who are working in the jungle; only 15% of the cases occur among women. Colombia's last urban yellow fever case occurred in 1929. At this time yellow fever is endemic in the eastern plains, which form part of the Amazone and Orinoco basins. It spreads in the form of epizootic and epidemic waves through the forests at the foot of the eastern cordillera. Yellow fever is endemo-epidemic in the northern and central jungle of Peru. Over 600 cases were reported from 1960-82. These cases occurred during the rainy season of January to May. Vaccination campaigns have been intensified during the last 3 years. Yellow fever is enzootic in the gallery forests of the tropical plain of the Orinoco Basin, Venezuela. The 15-55 age group is the group usually at risk, but 2% of the cases occur in children under age 5 and 2.8% in children under age 10. Between 1965-84, the countries of the Americas reported 2238 cases to the Pan American Health Organization, but this figure provides an incomplete idea of the real incidence of yellow fever. PMID:4052698

  16. Slope Streaks in the Antarctic Dry Valleys: Characteristics, Candidate Formation Mechanisms, and Implications for Slope Streak Formation in the Martian Environment

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Marchant, D. R.; Dickson, J. L.; Levy, J. S.; Morgan, G. A.

    2007-07-01

    Enigmatic slope streaks on Mars are apparently active today. Remarkably similar analogs in the Antarctic Dry Valleys hyperarid polar desert involve near-surface flow of saline meltwater and wicking to the surface; we examine implications for Mars.

  17. Parametric frequency upconversion, optical fiber transmission, and streak camera recording

    SciTech Connect

    Lowry, M.E.; Rotter, M.D.

    1987-01-30

    The use of optical fiber for the transmission of information over relatively long distances is being recognized as the only viable solution to many data transmission problems, particularly those requiring high information density and faithful temporal content. This necessary reliance upon the optical carrier has meant that the image-tube based optical streak camera is often the instrument of choice for recording single-shot multi-parameter events with high temporal resolution. However, current photocathode technology is incompatible with the trend of the optical fiber industry toward the use of the 1300 to 1600 nm wavelength regime. To retain the advantages of optical streak-camera recording and optical fiber transmission, a way must be found to ''upconvert'' the optical carrier to higher energy. This report describes the use of an intense lazer pump beam coincident with the IR signal into a non-linear crystal (LiIO/sub 3/) to increase the signal's frequency. A beam splitter is used to separate the signal from the pump beam at the detector. The physical theory underlying this process is described. (JDH)

  18. Microprocessor-controlled, wide-range streak camera

    SciTech Connect

    Amy E. Lewis, Craig Hollabaugh

    2006-09-01

    Bechtel Nevada/NSTec recently announced deployment of their fifth generation streak camera. This camera incorporates many advanced features beyond those currently available for streak cameras. The arc-resistant driver includes a trigger lockout mechanism, actively monitors input trigger levels, and incorporates a high-voltage fault interrupter for user safety and tube protection. The camera is completely modular and may deflect over a variable full-sweep time of 15 nanoseconds to 500 microseconds. The camera design is compatible with both large- and small-format commercial tubes from several vendors. The embedded microprocessor offers Ethernet connectivity, and XML [extensible markup language]-based configuration management with non-volatile parameter storage using flash-based storage media. The camera’s user interface is platform-independent (Microsoft Windows, Unix, Linux, Macintosh OSX) and is accessible using an AJAX [asynchronous Javascript and XML]-equipped modem browser, such as Internet Explorer 6, Firefox, or Safari. User interface operation requires no installation of client software or browser plug-in technology. Automation software can also access the camera configuration and control using HTTP [hypertext transfer protocol]. The software architecture supports multiple-simultaneous clients, multiple cameras, and multiple module access with a standard browser. The entire user interface can be customized.

  19. Range accuracy analysis of streak tube imaging lidar systems

    NASA Astrophysics Data System (ADS)

    Ye, Guangchao; Fan, Rongwei; Chen, Zhaodong; Yuan, Wei; Chen, Deying; He, Ping

    2016-02-01

    Streak tube imaging lidar (STIL) is an active imaging system that has a high range accuracy and a wide range gate with the use of a pulsed laser transmitter and streak tube receiver to produce 3D range images. This work investigates the range accuracy performance of STIL systems based on a peak detection algorithm, taking into account the effects of blurring of the image. A theoretical model of the time-resolved signal distribution, including the static blurring width in addition to the laser pulse width, is presented, resulting in a modified range accuracy analysis. The model indicates that the static blurring width has a significant effect on the range accuracy, which is validated by both the simulation and experimental results. By using the optimal static blurring width, the range accuracies are enhanced in both indoor and outdoor experiments, with a stand-off distance of 10 m and 1700 m, respectively, and corresponding, best range errors of 0.06 m and 0.25 m were achieved in a daylight environment.

  20. Microprocessor-controlled wide-range streak camera

    NASA Astrophysics Data System (ADS)

    Lewis, Amy E.; Hollabaugh, Craig

    2006-08-01

    Bechtel Nevada/NSTec recently announced deployment of their fifth generation streak camera. This camera incorporates many advanced features beyond those currently available for streak cameras. The arc-resistant driver includes a trigger lockout mechanism, actively monitors input trigger levels, and incorporates a high-voltage fault interrupter for user safety and tube protection. The camera is completely modular and may deflect over a variable full-sweep time of 15 nanoseconds to 500 microseconds. The camera design is compatible with both large- and small-format commercial tubes from several vendors. The embedded microprocessor offers Ethernet connectivity, and XML [extensible markup language]-based configuration management with non-volatile parameter storage using flash-based storage media. The camera's user interface is platform-independent (Microsoft Windows, Unix, Linux, Macintosh OSX) and is accessible using an AJAX [asynchronous Javascript and XML]-equipped modem browser, such as Internet Explorer 6, Firefox, or Safari. User interface operation requires no installation of client software or browser plug-in technology. Automation software can also access the camera configuration and control using HTTP [hypertext transfer protocol]. The software architecture supports multiple-simultaneous clients, multiple cameras, and multiple module access with a standard browser. The entire user interface can be customized.

  1. A possible role for chemotaxis in primitive streak formation

    NASA Astrophysics Data System (ADS)

    Sandersius, Sebastian A.; Weijer, Cornelis J.; Newman, Timothy J.

    2010-03-01

    One of the fundamental problems in modern biology is to understand the transformation of a fertilized egg to an adult organism. A key stage of this developmental process is gastrulation, in which cell germ layers are defined, and the basic three-dimensional body plan of the organism is established. Presented here is a model used to investigate the collective cell movement which is observed at the onset of gastrulation in the Chick embryo. In the avian embryo, gastrulation is initiated by a cadre of cells moving coherently, bisecting the embryo, thereby forming a structure known as the primitive streak. The mechanisms underlying primitive streak formation are the subject of recent experimental controversy. One hypothesis is that coherent cell motion is driven by chemotactic response to long-range signaling gradients. We will present results from large-scale computer simulations testing this hypothesis. In particular, we perform simulations using the Subcellular Element Model (SEM). Within the model framework, a single cell is represented by a collection of visco-elastically interacting elements. Dynamic interactions of elements are motivated, as coarse-grained representations, of the actively remodeling cell cytoskeleton. We have found that, in addition to chemotaxis, active cell migration is crucial for ``fluidizing" the tissue thereby allowing large-scale coherent cell movement.

  2. Interactions between performance pressure, performance streaks, and attentional focus.

    PubMed

    Gray, Rob; Allsop, Jonathan

    2013-08-01

    How is performance under pressure influenced by the history of events that precede it, and how does the pressure outcome influence the series of events that follow? A baseball batting simulation was used with college players to investigate these questions. In Experiment 1, the difficulty of the simulation was first adaptively adjusted to equate performance level. Batters next completed 20 at-bats used to classify them into one of three performance groups (normal, cold streak, or hot streak) followed by a one at-bat pressure condition. Finally, performance was evaluated over a period of 20 postpressure at-bats. In Experiment 2, a series of secondary tasks were added to assess attentional focus. In both experiments, whether batters succeeded or failed under pressure was significantly related to their performance history immediately before the pressure event, with the normal group having the poorest pressure performance. Performance postpressure was significantly related to both the pressure outcome and prepressure performance. These performance effects were related to changes in the batter's attentional focus as shown by changes in secondary task accuracy. PMID:23966447

  3. Immunohistochemistry comparing endoscopic vein harvesting vs. open vein harvesting on saphenous vein endothelium

    PubMed Central

    2014-01-01

    Objective The present study attempts to compare the immunohistochemistry (IHC) of von Willebrand factor (vWf) , endothelial cadherin, Caveolin and endothelial Nitric Oxide Synthase (eNOS) in VasoView Endoscopic Vein Harvesting (EVH) versus traditional Open Vein Harvesting (OVH) techniques for Coronary Artery Bypass Graft (CABG) Surgery performed in Javad al Aemeh Hospital of Mashhad, Iran in 2013,. Methods and materials Forty-seven patients were scheduled for CABG (30 EVH and 17 OVH) among whom patients with relatively same gender and similar age were selected. Three separate two cm vein samples were harvested from each patients saphenous vein. Each portion was collected from distal, middle and proximal zones of the saphenous vein. The tissues were deparaffinized, and antigen retrieval was done using EZ-retriever followed by an immunohistochemistry evaluation with vWf, e-cadherin, Caveolin and eNOS. In addition, demographic questioner as of Lipid profile, FBS, BMI, and cardiovascular risk factors were collected. Data analyses, including parametric and nonparametric tests were undertaken using the SPSS 16 software. A P value??0.05). Qualitative report of vWf, e-cadherin, Caveolin and eNOS reveals no significant difference between the EVH and OVH (P?>?0.05). Conclusion This study indicates that VasoView EVH technique causes no endothelial damage in comparison with OVH. This study could be a molecular confirmation for the innocuous of EVH technique. PMID:24938544

  4. Wigner-Smith time delay and its application to attosecond streaking

    NASA Astrophysics Data System (ADS)

    Goldsmith, Cory; Su, Jing; Becker, Andreas; Jaron-Becker, Agnieszka

    2015-05-01

    Attosecond streaking experiments have been suggested as a means for observing temporal delays in photoemission, but the interpretation of the time delays observed in such experiments is still debated. Using a calculation of the streaking delays as a field-weighted sum over finite-range delays accumulated over the duration of the streaking pulse length, we provide further analysis into the role the Coulomb potential plays in the observed, so-called ``streaking delay.'' To this end, we make use of cut-off Coulomb and single active electron (SAE) potentials to calculate field-free Wigner-Smith-like time delays accumulated over small intervals of time to formulate an analytical model for the calculation of the streaking delays for hydrogenic atoms, as well as for SAE model potentials for noble gases. Our results indicate that in most cases, the influence of the streaking field on the short-range parts of the potential is a small effect. This allows for the representation of the streaking delay as the sum of the Wigner-Smith (WS) delay from scattering theory and the coupling between the streaking and Coulomb fields. We acknowledge the following support: C.G., J.S., and A.B: U.S. DOE, Division of Chemical Sciences, Atomic, Molecular and Optical Sciences Program (Award No. DE-FG02-09ER16103), A.J.-B.: U.S. NSF (Grants No. PHY-1125844 and No. PHY-1068706).

  5. Genome Sequence of Banana Streak MY Virus from the Pacific Ocean Island of Tonga

    PubMed Central

    Stainton, Daisy; Halafihi, Manaia; Collings, David A.

    2015-01-01

    Banana streak disease is caused by a variety of banana-infecting badnaviruses. A genome of the episomal form of a banana streak MY virus was recovered from an infected banana plant sampled on Vavau Island, Tonga, and shares >98% pairwise identity with the six other genomes available in public databases. PMID:26021925

  6. X-ray streak camera diagnostics of picosecond laser-plasma interactions

    SciTech Connect

    Cobble, J.A.; Fulton, R.D.; Jones, L.A.; Kyrala, G.A.; Schappert, G.T.; Taylor, A.J.; Wahlin, E.K.

    1992-01-01

    An x-ray streak camera is used to diagnose a laser-produced Al plasma with time resolution of {approximately}10 ps. A streak record of filtered emission and a time-integrated transmission grating spectrum reveal that the plasma radiation is dominated by emission from He- and H-like resonance lines. 11 refs.

  7. X-ray streak camera diagnostics of picosecond laser-plasma interactions

    SciTech Connect

    Cobble, J.A.; Fulton, R.D.; Jones, L.A.; Kyrala, G.A.; Schappert, G.T.; Taylor, A.J.; Wahlin, E.K.

    1992-05-01

    An x-ray streak camera is used to diagnose a laser-produced Al plasma with time resolution of {approximately}10 ps. A streak record of filtered emission and a time-integrated transmission grating spectrum reveal that the plasma radiation is dominated by emission from He- and H-like resonance lines. 11 refs.

  8. Genome Sequence of Banana Streak MY Virus from the Pacific Ocean Island of Tonga.

    PubMed

    Stainton, Daisy; Halafihi, Mana'ia; Collings, David A; Varsani, Arvind

    2015-01-01

    Banana streak disease is caused by a variety of banana-infecting badnaviruses. A genome of the episomal form of a banana streak MY virus was recovered from an infected banana plant sampled on Vava'u Island, Tonga, and shares >98% pairwise identity with the six other genomes available in public databases. PMID:26021925

  9. Nephrotic Syndrome Associated with Renal Vein Thrombosis

    PubMed Central

    Kang, Sung Kyew; Park, Sung Kwang

    1987-01-01

    The coexistence of nephrotic syndrome and renal vein thrombosis has been of medical interest since Rayers description in 1840. Renal vein thrombosis has been underdiagnosed because of its variable clinical and radiological findings but it becomes a more frequently recognizable clinical entity since diagnosis can be easily established by modern angiographic techniques. Generally it has been believed that renal vein thrombosis may cause nephrotic syndrome. But recent articles strongly suggest that renal vein thrombosis is a complication of the nephrotic syndrome rather than a cause. We report three cases of nephrotic syndrome associated with renal vein thrombosis. PMID:3154812

  10. Smog Yellows Taj Mahal

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Built as a monument to the favorite wife of the Mughal Emperor Shah Jahan, the Taj Mahal has watched over the city of Agra, India, since the mid-seventeenth century with its pillars of gleaming white marble. By the spring of 2007, however, one of the world's most visited landmarks was turning yellow, and a panel of India's parliament had little trouble identifying the culprit: pollution. The panel blamed particles of soot and dirt suspended high in the atmosphere for the Taj Mahal's dinginess. The Taj Mahal's home, Agra, sits not far from the base of the Himalaya, and smog regularly collects along the southern side of the mountain range. On May 16, 2007, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured this image of the area around Agra, India. The closeup image shows the immediate vicinity of the Taj Majal. The larger image shows the surrounding area. In both pictures, dingy, gray-beige haze obscures the satellite's view of the land surface. India had tried to minimize the adverse impact of air pollution on the famous landmark. According to the BBC, in the late 1990s, India's Supreme Court ordered the closure of thousands of iron foundries and kilns that had belched smoke near the monument. Many of the 3 million tourists who visited the Taj Majal each year approached the monument on horse-drawn carriages or battery-operated buses as fossil-fuel-powered vehicles could not drive within 2 kilometers (1.5 miles). Since those efforts have failed to save the Taj Majal's complexion, Indian officials have considered applying a cleansing mud pack to the monument's surface to draw out the dirt. As India industrializes, smog results, and the Taj Mahal's gleaming whiteness is only one casualty. Pollution has been blamed for a decrease in Indian rice harvests, which had soared during the 'Green Revolution' of the 1960s and 1970s. Haze and dust also appear to bring on the region's monsoon rains earlier than normal.

  11. Satellite Observations of Plume-like Streaks in a Cloud Field in Canada

    NASA Astrophysics Data System (ADS)

    Grasso, Lewis; Lindsey, Daniel T.; Seaman, Curtis J.; Stocks, Brian; Rabin, Robert M.

    2015-04-01

    On the afternoon of 28 October 2013, plume-like streaks were detected by geostationary and polar orbiting satellites over eastern Ontario, Canada. These streaks were characterized by enhanced reflectivity in the visible bands and warmer brightness temperatures at 3.9 µm. These streaks were part of a low-level liquid water cloud layer. Due to the similarity of the streaks to plume-like features in marine stratocumulus caused by smoke from the stacks of ships, so-called ship tracks, a local source of emitted aerosols was suspected and subsequently identified as the burning of logging residue. This event provides further support for the ability of locally enhanced aerosol loading to alter microphysical characteristics of clouds. Ship tracks, pollution plumes from industrial burning, and pyro-cumulus are known examples of this type of interaction. In addition, the plume-like streaks could be used indirectly to identify the location of the source of the emitted particles.

  12. Characterization of X-ray streak cameras for use on Nova

    SciTech Connect

    Kalantar, D.H.; Bell, P.M.; Costa, R.L.; Hammel, B.A.; Landen, O.L.; Orzechowski, T.J.; Hares, J.D.; Dymoke-Bradshaw, A.K.L.

    1996-10-01

    There are many different types of measurements that require a continuous time history of x-ray emission that can be provided with an x-ray streak camera. In order to properly analyze the images that are recorded with the x-ray streak cameras operated on Nova, it is important to account for the streak characterization of each camera. We have performed a number of calibrations of the streak cameras both on the bench as well as with Nova disk target shots where we use a time modulated laser intensity profile (self-beating of the laser) an the target to generate an x-ray comb. We have measured the streak camera sweep direction and spatial offset, curvature of the electron optics, sweep rate, and magnification and resolution of the electron optics.

  13. Characterization of X-ray streak cameras for use on Nova

    SciTech Connect

    Kalantar, D.H.; Bell, P.M.; Costa, R.L.; Hammel, B.A.; Landen, O.L.; Orzechowski, T.J.; Hares, J.D.; Dymoke-Bradshaw, A.K.L.

    1996-09-01

    There are many different types of measurements that require a continuous time history of x-ray emission that can be provided with an x-ray streak camera. In order to properly analyze the images that are recorded with the x-ray streak cameras operated on Nova, it is important to account for the streak characterization of each camera. We have performed a number of calibrations of the streak cameras both on the bench as well as with Nova disk target shots where we use a time modulated laser intensity profile (self-beating of the laser) on the target to generate an x-ray comb. We have measured the streak camera sweep direction and spatial offset, curvature of the electron optics, sweep rate, and magnification and resolution of the electron optics.

  14. Decoupling of amniote gastrulation and streak formation reveals a morphogenetic unity in vertebrate mesoderm induction.

    PubMed

    Alev, Cantas; Wu, Yuping; Nakaya, Yukiko; Sheng, Guojun

    2013-07-01

    Mesoderm is formed during gastrulation. This process takes place at the blastopore in lower vertebrates and in the primitive streak (streak) in amniotes. The evolutionary relationship between the blastopore and the streak is unresolved, and the morphogenetic and molecular changes leading to this shift in mesoderm formation during early amniote evolution are not well understood. Using the chick model, we present evidence that the streak is dispensable for mesoderm formation in amniotes. An anamniote-like circumblastoporal mode of gastrulation can be induced in chick and three other amniote species. The induction requires cooperative activation of the FGF and Wnt pathways, and the induced mesoderm field retains anamniote-like dorsoventral patterning. We propose that the amniote streak is homologous to the blastopore in lower vertebrates and evolved from the latter in two distinct steps: an initial pan-amniote posterior restriction of mesoderm-inducing signals; and a subsequent lineage-specific morphogenetic modification of the pre-ingression epiblast. PMID:23698348

  15. Betting Decision Under Break-Streak Pattern: Evidence from Casino Gaming.

    PubMed

    Fong, Lawrence Hoc Nang; So, Amy Siu Ian; Law, Rob

    2016-03-01

    Cognitive bias is prevalent among gamblers, especially those with gambling problems. Grounded in the heuristics theories, this study contributes to the literature by examining a cognitive bias triggered by the break streak pattern in the casino setting. We postulate that gamblers tend to bet on the latest outcome when there is a break-streak pattern. Moreover, three determinants of the betting decision under break-streak pattern, including the streak length of the alternative outcome, the frequency of the latest outcome, and gender, were identified and examined in this study. A non-participatory observational study was conducted among the Cussec gamblers in a casino in Macao. An analysis of 1229 bets confirms our postulation, particularly when the streak of the alternative outcome is long, the latest outcome is frequent, and the gamblers are females. The findings provide meaningful implications for casino management and public policymakers regarding the minimization of gambling harm. PMID:25967106

  16. Deep vein thrombosis risk stratification.

    PubMed

    Nitta, Daisuke; Mitani, Haruo; Ishimura, Rieko; Moriya, Manabu; Fujimoto, Yo; Ishiwata, Sugao; Yamaguchi, Tetsu; Ohno, Minoru

    2013-01-01

    Pulmonary thromboembolism (PTE) is a life-threatening disease which always presents in patients with deep vein thrombosis (DVT). There are few statements in guidelines regarding indications for anticoagulation based on the location of DVT. We investigated whether the relative risk of PTE depends on thrombus location and bleeding complications with anticoagulation therapy. Between January 1 and July 10, 2007, 461 patients underwent lower extremity venous ultrasound studies, and 129 patients were diagnosed as DVT (60 males, 66.9 13.3 years). We retrospectively studied the incidence of PTE and bleeding complications associated with anticoagulation therapy. Average follow-up period was 536 324 days. Above and below knee thrombosis was present in 60 and 69 patients, respectively. Warfarin was administered in 60 patients. Nine patients developed PTE. Multivariate analysis showed the absence of anticoagulation therapy and location of DVT (above knee) to be significantly correlated with onset of PTE (anticoagulation; P < 0.01, location; P = 0.02). However, the incidence of bleeding was not significantly different between above knee and below knee vein thrombosis (P = 0.72). In conclusion, below knee vein thrombosis carries a relatively low risk of PTE, but the incidence of bleeding complications does not depend on thrombosis location. This suggests that the indication of anticoagulation therapy should be based on DVT location. PMID:23774241

  17. StreakDet data processing and analysis pipeline for space debris optical observations

    NASA Astrophysics Data System (ADS)

    Virtanen, Jenni; Flohrer, Tim; Muinonen, Karri; Granvik, Mikael; Torppa, Johanna; Poikonen, Jonne; Lehti, Jussi; Santti, Tero; Komulainen, Tuomo; Naranen, Jyri

    We describe a novel data processing and analysis pipeline for optical observations of space debris. The monitoring of space object populations requires reliable acquisition of observational data, to support the development and validation of space debris environment models, the build-up and maintenance of a catalogue of orbital elements. In addition, data is needed for the assessment of conjunction events and for the support of contingency situations or launches. The currently available, mature image processing algorithms for detection and astrometric reduction of optical data cover objects that cross the sensor field-of-view comparably slowly, and within a rather narrow, predefined range of angular velocities. By applying specific tracking techniques, the objects appear point-like or as short trails in the exposures. However, the general survey scenario is always a track before detect problem, resulting in streaks, i.e., object trails of arbitrary lengths, in the images. The scope of the ESA-funded StreakDet (Streak detection and astrometric reduction) project is to investigate solutions for detecting and reducing streaks from optical images, particularly in the low signal-to-noise ratio (SNR) domain, where algorithms are not readily available yet. For long streaks, the challenge is to extract precise position information and related registered epochs with sufficient precision. Although some considerations for low-SNR processing of streak-like features are available in the current image processing and computer vision literature, there is a need to discuss and compare these approaches for space debris analysis, in order to develop and evaluate prototype implementations. In the StreakDet project, we develop algorithms applicable to single images (as compared to consecutive frames of the same field) obtained with any observing scenario, including space-based surveys and both low- and high-altitude populations. The proposed processing pipeline starts from the segmentation of the acquired image (i.e., the extraction of all sources), followed by the astrometric and photometric characterization of the candidate streaks, and ends with orbital validation of the detected streaks. A central concept of the pipeline is streak classification which guides the actual characterization process by aiming to identify the interesting sources and to filter out the uninteresting ones, as well as by allowing the tailoring of algorithms for specific streak classes (e.g. point-like vs. long, disintegrated streaks). To validate the single-image detections, the processing is finalized by orbital analysis, resulting in preliminary orbital classification (Earth-bound vs. non-Earth-bound orbit) for the detected streaks.

  18. X-ray Streak Diagnostics on Nike Laser Experiments

    NASA Astrophysics Data System (ADS)

    Serlin, V.; Obenschain, S. P.; Sethian, J. D.; Mostovych, A. N.; Dahlburg, J. P.; Schmitt, A. J.; Gardner, J. H.; Lehecka, T.

    1998-11-01

    We use an x-ray streak camera looking side-on at planar targets in several Nike laser experiments. The measurements include self emission from target blow off and x-ray sidelighting. The laser illuminated sidelighter target material is chosen to match the needs of a given experiment. The silicon line at 1.86 keV and chlorine line at 2.7 keV are used most often. X-ray sidelighting is used to investigate the acceleration of both solid plastic and foam targets filled with liquid deuterium. We are also using it to measure shock propagation in empty and deuterium filled foam targets. We employ the camera to study the evolution of radiative plasma structures (RPS) via x-ray emission from the target blow off plasma. Results and plans for future work will be presented.

  19. The new design of the THz streak camera at PSI

    NASA Astrophysics Data System (ADS)

    Gorgisyan, I.; Juranic, P. N.; Ischebeck, R.; Stepanov, A.; Schlott, V.; Pradervand, C.; Patthey, L.; Radovic, M.; Abela, R.; Hauri, C. P.; Monoszlai, B.; Ivanov, R.; Peier, P.; Liu, J.; Togashi, T.; Owada, S.; Ogawa, K.; Katayama, T.; Yabashi, M.; Rivkin, L.

    2015-05-01

    SwissFEL is the Free Electron Laser (FEL) facility under construction at the Paul Scherrer institute (PSI), aiming to provide users with X-ray pulses of lengths down to 2 femtoseconds at standard operation. The measurement of the length of the FEL pulses and their arrival time relative to the experimental laser is crucial for the pump-probe experiments carried out in such facilities. This work presents a new device that measures hard X-ray FEL pulses based on the THz streak camera concept. It describes the prototype setup called pulse arrival and length monitor (PALM) developed at PSI and tested in Spring-8 Angstrom Compact Free Electron Laser (SACLA) in Japan. Based on the first results obtained from the measurements, we introduce the new improved design of the second generation PALM setup that is currently under construction and will be used in SwissFEL photon diagnostics.

  20. Genetic variants of Banana streak virus in Mauritius.

    PubMed

    Jaufeerally-Fakim, Y; Khorugdharry, Ashwin; Harper, Glyn

    2006-01-01

    Genetic variations among isolates of Banana streak virus (BSV) were assessed using two sets of primers. The virus, found in banana accessions in Mauritius, was compared to a Nigerian isolate from cultivar Obino l'Ewai (BSOEV). On the basis of the observed size of amplicons, some Mauritius strains were different from l'Ewai BSOEV. Both Southern blot hybridization and the nucleotide sequences of the PCR products confirmed that they were of episomal BSV origin. An isolate of sugarcane bacilliform virus (SCBV) was found to be also very similar to the BSV isolated from banana samples. Nucleotide sequence analysis showed that even the same size PCR products had differing sequences. The dendrogram placed the isolates from Mauritius in a cluster separate from BSV and SCBV from other geographical locations. PMID:16143419

  1. Interference effects in angular streaking with a rotating terahertz field

    NASA Astrophysics Data System (ADS)

    Kazansky, A. K.; Bozhevolnov, A. V.; Sazhina, I. P.; Kabachnik, N. M.

    2016-01-01

    A method of angular streaking with a rotating terahertz electric field for photoelectrons produced by femtosecond extreme ultraviolet pulses is suggested and theoretically analyzed. The method can be used for free electron laser (FEL) pulse characterization on a shot-to-shot basis. It is shown that in related measurements an interesting phenomenon appears: formation of very bright and sharp features in the angular resolved electron spectra measured in the plane perpendicular to the collinear beam direction. These features are similar to the conventional caustics in the wave propagation. The caustics are accompanied by a well-developed interference structure. The intensity distribution along the caustic is determined by the envelope of the FEL pulse.

  2. Vein harvesting and techniques for infrainguinal bypass.

    PubMed

    Albäck, Anders; Saarinen, Eva; Venermo, Maarit

    2016-04-01

    In order to achieve good long term results after bypass surgery, alongside with good inflow and outflow arteries, the bypass graft material also has an important role. The best patency and limb salvage rates are achieved with autologous vein. If great saphenous vein is not available, acceptable long-term results can be achieved with arm veins and lesser saphenous vein. The quality and size of the vein are important. A small-caliber vein, increased wall thickness, postphlebitic changes and varicosities are associated with a risk of early failure. Preoperative vein mapping with ultrasound reduces readmissions and postoperative surgical site infections. During the mapping, the vein to be used and its main tributaries are marked with a permanent marker pen. To reduce wound complication rates we recommend bridged incisions in vein harvesting. Endoscopic vein harvesting seems to have no benefit compared to open techniques in lower limb bypasses, and has been associated with higher risk of primary patency loss at one year. With deep tunneling of the graft the problems caused by wound infection can be avoided. PMID:26837257

  3. Neutron streak and framing camera diagnostics for ICF implosions

    NASA Astrophysics Data System (ADS)

    Jaanimagi, Paul A.; Bradley, David K.

    1993-01-01

    Detailed measurements of the time dependence of the neutron flux from the implosion of DT- and/or DD-filled targets are required to better our understanding of inertial confinement fusion. Past efforts at developing fast neutron detectors have generally suffered from a lack of sensitivity and/or insufficient time resolution. In this paper we report on a new streak camera diagnostic for directly time-resolving the neutron burnwidth for ICF implosions. The technique uses the (n,p) reaction in CH2 to convert the neutron signal to a proton signal, which is proximity coupled to a CsI secondary electron emitter and is subsequently recorded with a standard LLE large-format x-ray streak camera. An x-ray signal is recorded simultaneously with the neutron-produced signal and provides an accurate timing fiducial for burn-time measurements. We have recorded usable signals from the implosion of DT-filled targets producing yields of 3 X 10 10 neutrons, with a target to photocathode distance of 30 cm. The calculated time resolution is better than 20 ps for 14 MeV neutrons and 10 ps for 2.45 MeV neutrons. Our technique for recording the neutron flux can also be extended to high-speed framing cameras, currently capable of 35-ps-duration gate times. The framing cameras will permit the simultaneous recording of the burnwidth and the neutron energy spectrum. Also, time-resolved neutron imaging of the core will be possible for DD yields > 1012.

  4. Dynamic range measurements on streak image tubes with internal and external microchannel plate image amplification

    NASA Astrophysics Data System (ADS)

    Eagleton, R. T.; James, S. F.

    2003-03-01

    Electron-optic streak chronoscopy is an important diagnostic technique for the diagnosis of laser driven hydrodynamic and radiative phenomenon. To minimize the undesirable effects of excessive space charge in streak image tubes an image amplification stage is often used. Microchannel plate (MCP) electron amplifiers are frequently employed for this purpose. These devices may be utilized in two ways: either to amplify light from the streak image tube phosphor screen by externally coupling a proximity-focus MCP wafer intensifier tube, or by insertion inside the streak tube body to amplify the streaked electrons directly. To investigate how the operating regime of the MCP influences the dynamic range of the streak camera system, dynamic range measurements have been made on two identical streak image tubes (English Electric Valve Co. type P8307) one incorporating an internal MCP, the other, externally coupled image amplification. Dynamic range measurements have been made for 30 ps full width half maximum (FWHM) and 100 ps (FWHM) laser pulses and comparison made to a previous study of this type of image tube. For internal MCP and externally coupled intensifier camera systems of equal radiant gain the dynamic range for the pulse widths studied was found to be comparable.

  5. Cholestatic presentation of yellow phosphorus poisoning.

    PubMed

    Lakshmi, C P; Goel, Amit; Basu, Debdatta

    2014-01-01

    Yellow phosphorus, a component of certain pesticide pastes and fireworks, is well known to cause hepatotoxicity. Poisoning with yellow phosphorus classically manifests with acute hepatitis leading to acute liver failure which may need liver transplantation. We present a case of yellow phosphorus poisoning in which a patient presented with florid clinical features of cholestasis highlighting the fact that cholestasis can rarely be a presenting feature of yellow phosphorus hepatotoxicity. PMID:24554916

  6. Clay veins: Their occurrence, characteristics, and support

    SciTech Connect

    Chase, F.E.; Ulery, J.P.

    1987-01-01

    These detrimental aspects have prompted the Bureau of Mines to investigate the physical characteristics of and roof instability problems associated with clay veins. The investigators found that clay veins normally occur in more stable, less rapidly subsiding coal basins. Clay veins result when tensile stresses develop fissures that are later infilled. These fissures can be propagated by compactional processes and/or tectonic stresses during and subsequent to coalification. The Bureau also found that associated faults, fractures, and slickenside planes commonly parallel clay veins and disrupt the lateral continuity of the immediate and, sometimes, main roof. When clay veins parallel or subparallel the direction of face advance, the roof is segmented into cantilever beams, causing unstable conditions. Consequently, the strate on either side of the clay veins should be bolted and strapped together to form a beam.

  7. Recanalized umbilical vein in portal hypertension.

    PubMed

    Aagaard, J; Jensen, L I; Sørensen, T I; Christensen, U; Burcharth, F

    1982-12-01

    Experience with splenoportography suggests that patency of the umbilical vein occurs in about 9% of the patients with portal hypertension. A widely patent umbilical vein might serve as a decompressive portosystemic shunt. Percutaneous transhepatic portography was performed in 107 patients with cirrhosis of the liver and portal hypertension. A patent umbilical vein was found in 28 patients (26%). This finding significantly paralleled the number and size of other collateral veins, apart from gastroesophageal varices. No significant relation was found between umbilical vein patency and portal pressure, extrahepatic shunting, variceal bleeding, or ascites. It is concluded that a large patent umbilical vein does not effectively relieve portal hypertension, prevent gastroesophageal varices, or protect against variceal bleeding or ascites. PMID:6983253

  8. Portal vein thrombosis during pregnancy

    PubMed Central

    Dasari, Papa; Balusamy, Sathyalakshmy

    2013-01-01

    A 22-year-old primigravida was diagnosed to have portal vein thrombosis during 20th week of gestation by ultrasound examination which was carried out to rule out congenital fetal anomalies. She had splenomegaly and thrombocytopenia. Investigations did not reveal any prothrombotic disorder. She was managed with anticoagulants which were started at 31?weeks of pregnancy. Labour was induced at 40?weeks of gestation and she delivered a healthy neonate without any complications. Anticoagulants were restarted after delivery and continued through the postpartum period and up to 6?months thereafter. PMID:23715832

  9. Ultra Fast X-ray Streak Camera for TIM Based Platforms

    SciTech Connect

    Marley, E; Shepherd, R; Fulkerson, E S; James, L; Emig, J; Norman, D

    2012-05-02

    Ultra fast x-ray streak cameras are a staple for time resolved x-ray measurements. There is a need for a ten inch manipulator (TIM) based streak camera that can be fielded in a newer large scale laser facility. The LLNL ultra fast streak camera's drive electronics have been upgraded and redesigned to fit inside a TIM tube. The camera also has a new user interface that allows for remote control and data acquisition. The system has been outfitted with a new sensor package that gives the user more operational awareness and control.

  10. Ultra fast x-ray streak camera for ten inch manipulator based platforms

    SciTech Connect

    Marley, E. V.; Shepherd, R.; Fulkerson, S.; James, L.; Emig, J.; Norman, D.

    2012-10-15

    Ultra fast x-ray streak cameras are a staple for time resolved x-ray measurements. There is a need for a ten inch manipulator (TIM) based streak camera that can be fielded in a newer large scale laser facility. The Lawrence Livermore National Laboratory ultra fast streak camera's drive electronics have been upgraded and redesigned to fit inside a TIM tube. The camera also has a new user interface that allows for remote control and data acquisition. The system has been outfitted with a new sensor package that gives the user more operational awareness and control.

  11. Emissivity spectrum of a large "dark streak" from themis infrared imagery

    SciTech Connect

    Brumby, Steven P.; Vaniman, D. T.; Bish, D. L.

    2003-01-01

    'Dark streaks', also known as 'slope streaks', are unusual surface features found on Mars that are known to appear and fade away on timescales of years. Various explanations have been proposed for their origin and composition, including dry avalanches and wet debris or precipitates from brines. Previous investigations have been based on analysis of panchromatic imagery and altimetry from Viking and Mars Global Surveyor missions. We have obtained an infrared emissivity spectrum of a large dark streak on the north western edge of Olympus Mons, using imagery from the THEMIS instrument on the Mars Odyssey 2001 spacecraft.

  12. Streak camera crosstalk reduction using a multiple delay optical fiber bundle.

    PubMed

    Tsikouras, Anthony; Ning, Jin; Ng, Sandy; Berman, Richard; Andrews, David W; Fang, Qiyin

    2012-01-15

    The streak camera is one of the fastest photodetection systems, while its capability of multiplexing is particularly attractive to many applications requiring parallel data acquisition. The degree of multiplexing in a streak camera is limited by the crosstalk between input channels. We developed a technique that introducing a fixed time delay between adjacent fiber channels in a customized two-dimensional to one-dimensional fiber array to significantly reduce crosstalk both at the sample plane and at the input of a streak camera. A prototype system has been developed that supports 100 input channels, and its performance in fluorescence microscopy is demonstrated. PMID:22854483

  13. Ultra fast x-ray streak camera for ten inch manipulator based platforms.

    PubMed

    Marley, E V; Shepherd, R; Fulkerson, S; James, L; Emig, J; Norman, D

    2012-10-01

    Ultra fast x-ray streak cameras are a staple for time resolved x-ray measurements. There is a need for a ten inch manipulator (TIM) based streak camera that can be fielded in a newer large scale laser facility. The Lawrence Livermore National Laboratory ultra fast streak camera's drive electronics have been upgraded and redesigned to fit inside a TIM tube. The camera also has a new user interface that allows for remote control and data acquisition. The system has been outfitted with a new sensor package that gives the user more operational awareness and control. PMID:23126928

  14. Deep Vein Thrombosis (DVT) / Pulmonary Embolism (PE) - Blood Clot Forming in a Vein

    MedlinePLUS

    ... Espaol (Spanish) Recommend on Facebook Tweet Share Compartir Deep Vein Thrombosis and Pulmonary Embolism (DVT/PE) are often underdiagnosed and serious, but preventable medical conditions. Deep vein thrombosis (DVT) is a medical condition that ...

  15. Coronary vein graft disease: Pathogenesis and prevention

    PubMed Central

    Parang, Pirouz; Arora, Rohit

    2009-01-01

    Not long after coronary artery bypass grafting surgery was described, several reports presented follow-up angiographic data on large cohorts of patients, demonstrating that approximately one-half of saphenous vein grafts fail within 10 to 15 years of surgery and that graft failure is associated with worse clinical outcomes. Three processes are responsible for vein graft failure. Thrombosis, intimal hyperplasia and accelerated atherosclerosis contribute to graft failure in the acute, subacute and late postoperative periods, respectively. Studies have shown that perioperative antiplatelet therapy can reduce early thrombosis and graft failure. As in native coronaries, intensive lipid lowering can attenuate the process of atherosclerosis in vein grafts. Intimal hyperplasia in the vein graft is thought to be an adaptation of the vein to higher pressures in the arterial circulation. This process is further promoted by the loss of inhibition from the endothelial layer, which is injured during surgery. A new no-touch technique for harvesting grafts may be effective in preventing disruption to the endothelial layer, and subsequent intimal hyperplasia and graft loss. Off-pump surgery and endoscopic vein harvesting, which are known to reduce surgical morbidity, have been shown to be no worse than on-pump surgery and open vein harvesting, respectively, in terms of vein graft patency. Various gene therapies can prevent intimal hyperplasia in animal models, but human data obtained so far have been disappointing. Placing an external stent around a vein graft may reduce tangential wall stress and subsequent intimal hyperplasia. PMID:19214303

  16. Remodelling of the Superior Caval Vein After Angioplasty in an Infant with Superior Caval Vein Syndrome

    SciTech Connect

    Mert, Murat Saltik, Levent; Gunay, Ilhan

    2004-08-15

    An 8-month old girl was presented with superior caval vein syndrome early after cardiac surgery. Angiography showed severe stenosis of the superior caval vein with 50 mmHg pressure gradient. Following balloon angioplasty, the pressure gradient was reduced to 7 mmHg with some residual stenosis of the superior caval vein. When the patient was reevaluated 5 months after the procedure, angiography revealed a normal diameter of the superior caval vein without a pressure gradient.

  17. Analyses of Twelve New Whole Genome Sequences of Cassava Brown Streak Viruses and Ugandan Cassava Brown Streak Viruses from East Africa: Diversity, Supercomputing and Evidence for Further Speciation.

    PubMed

    Ndunguru, Joseph; Sseruwagi, Peter; Tairo, Fred; Stomeo, Francesca; Maina, Solomon; Djinkeng, Appolinaire; Kehoe, Monica; Boykin, Laura M

    2015-01-01

    Cassava brown streak disease is caused by two devastating viruses, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) which are frequently found infecting cassava, one of sub-Saharan Africa's most important staple food crops. Each year these viruses cause losses of up to $100 million USD and can leave entire families without their primary food source, for an entire year. Twelve new whole genomes, including seven of CBSV and five of UCBSV were uncovered in this research, doubling the genomic sequences available in the public domain for these viruses. These new sequences disprove the assumption that the viruses are limited by agro-ecological zones, show that current diagnostic primers are insufficient to provide confident diagnosis of these viruses and give rise to the possibility that there may be as many as four distinct species of virus. Utilizing NGS sequencing technologies and proper phylogenetic practices will rapidly increase the solution to sustainable cassava production. PMID:26439260

  18. Analyses of Twelve New Whole Genome Sequences of Cassava Brown Streak Viruses and Ugandan Cassava Brown Streak Viruses from East Africa: Diversity, Supercomputing and Evidence for Further Speciation

    PubMed Central

    Ndunguru, Joseph; Sseruwagi, Peter; Tairo, Fred; Stomeo, Francesca; Maina, Solomon; Djinkeng, Appolinaire; Kehoe, Monica; Boykin, Laura M.

    2015-01-01

    Cassava brown streak disease is caused by two devastating viruses, Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) which are frequently found infecting cassava, one of sub-Saharan Africa’s most important staple food crops. Each year these viruses cause losses of up to $100 million USD and can leave entire families without their primary food source, for an entire year. Twelve new whole genomes, including seven of CBSV and five of UCBSV were uncovered in this research, doubling the genomic sequences available in the public domain for these viruses. These new sequences disprove the assumption that the viruses are limited by agro-ecological zones, show that current diagnostic primers are insufficient to provide confident diagnosis of these viruses and give rise to the possibility that there may be as many as four distinct species of virus. Utilizing NGS sequencing technologies and proper phylogenetic practices will rapidly increase the solution to sustainable cassava production. PMID:26439260

  19. Adaptive evolution by recombination is not associated with increased mutation rates in Maize streak virus

    PubMed Central

    2012-01-01

    Background Single-stranded (ss) DNA viruses in the family Geminiviridae are proving to be very useful in real-time evolution studies. The high mutation rate of geminiviruses and other ssDNA viruses is somewhat mysterious in that their DNA genomes are replicated in host nuclei by high fidelity host polymerases. Although strand specific mutation biases observed in virus species from the geminivirus genus Mastrevirus indicate that the high mutation rates in viruses in this genus may be due to mutational processes that operate specifically on ssDNA, it is currently unknown whether viruses from other genera display similar strand specific mutation biases. Also, geminivirus genomes frequently recombine with one another and an alternative cause of their high mutation rates could be that the recombination process is either directly mutagenic or produces a selective environment in which the survival of mutants is favoured. To investigate whether there is an association between recombination and increased basal mutation rates or increased degrees of selection favoring the survival of mutations, we compared the mutation dynamics of the MSV-MatA and MSV-VW field isolates of Maize streak virus (MSV; Mastrevirus), with both a laboratory constructed MSV recombinant, and MSV recombinants closely resembling MSV-MatA. To determine whether strand specific mutation biases are a general characteristic of geminivirus evolution we compared mutation spectra arising during these MSV experiments with those arising during similar experiments involving the geminivirus Tomato yellow leaf curl virus (Begomovirus genus). Results Although both the genomic distribution of mutations and the occurrence of various convergent mutations at specific genomic sites indicated that either mutation hotspots or selection for adaptive mutations might elevate observed mutation rates in MSV, we found no association between recombination and mutation rates. Importantly, when comparing the mutation spectra of MSV and TYLCV we observed similar strand specific mutation biases arising predominantly from imbalances in the complementary mutations G → T: C → A. Conclusions While our results suggest that recombination does not strongly influence mutation rates in MSV, they indicate that high geminivirus mutation rates are at least partially attributable to increased susceptibility of all geminivirus genomes to oxidative damage while in a single stranded state. PMID:23268599

  20. Idiopathic Bilateral External Jugular Vein Thrombosis

    PubMed Central

    Hindi, Zakaria; Fadel, Ehab

    2015-01-01

    Patient: Male, 21 Final Diagnosis: Idiopathic bilateral external jugular vein thrombosis Symptoms: Face engorgement neck swelling Medication: Clinical Procedure: None Specialty: Hematology Objective: Unknown ethiology Background: Vein thrombosis is mainly determined by 3 factors, which constitute a triad called Virchows triad: hypercoagulability, stasis, and endothelial injury. Venous thrombosis commonly occurs in the lower extremities since most of the blood resides there and flows against gravity. The veins of the lower extremities are dependent on intact valves and fully functional leg muscles. However, in case of valvular incompetency or muscular weakness, thrombosis and blood stasis will occur as a result. In contrast, the veins of the neck, specially the jugulars, have distensible walls which allow flexibility during respiration. In addition, the blood directly flows downward towards the heart. Nevertheless, many case reports mentioned the thrombosis of internal jugular veins and external jugular veins with identified risk factors. Jugular vein thrombosis has previously been associated in the literature with a variety of medical conditions, including malignancy. Case Report: This report is of a case of idiopathic bilateral external jugular vein thrombosis in a 21 year-old male construction worker of Southeast Asian origin with no previous medical history who presented with bilateral facial puffiness of gradual onset over 1 month. Doppler ultrasound and computed tomography were used in the diagnosis. Further work-up showed no evidence of infection or neoplasia. The patient was eventually discharged on warfarin. The patient was assessed after 6 months and his symptoms had resolved completely. Conclusions: Bilateral idiopathic external jugular veins thrombosis is extremely rare and can be an indicator of early malignancy or hidden infection. While previous reports in the literature have associated jugular vein thrombosis with malignancy, the present case shows that external jugular vein thrombosis can also be found in persons without malignancy. PMID:26301793

  1. Standard design for National Ignition Facility x-ray streak and framing cameras

    SciTech Connect

    Kimbrough, J. R.; Bell, P. M.; Bradley, D. K.; Holder, J. P.; Kalantar, D. K.; MacPhee, A. G.; Telford, S.

    2010-10-15

    The x-ray streak camera and x-ray framing camera for the National Ignition Facility were redesigned to improve electromagnetic pulse hardening, protect high voltage circuits from pressure transients, and maximize the use of common parts and operational software. Both instruments use the same PC104 based controller, interface, power supply, charge coupled device camera, protective hermetically sealed housing, and mechanical interfaces. Communication is over fiber optics with identical facility hardware for both instruments. Each has three triggers that can be either fiber optic or coax. High voltage protection consists of a vacuum sensor to enable the high voltage and pulsed microchannel plate phosphor voltage. In the streak camera, the high voltage is removed after the sweep. Both rely on the hardened aluminum box and a custom power supply to reduce electromagnetic pulse/electromagnetic interference (EMP/EMI) getting into the electronics. In addition, the streak camera has an EMP/EMI shield enclosing the front of the streak tube.

  2. A little winning streak: the reptilian-eye view of gastrulation in birds.

    PubMed

    Bertocchini, Federica; Alev, Cantas; Nakaya, Yukiko; Sheng, Guojun

    2013-01-01

    The primitive streak is where the mesoderm and definitive endoderm precursor cells ingress from the epiblast during gastrulation. It is often described as an embryological feature common to all amniotes. But such a feature has not been associated with gastrulation in any reptilian species. A parsimonious model would be that the primitive streak evolved independently in the avian and mammalian lineages. Looking beyond the primitive streak, can one find shared features of mesoderm and endoderm formation during amniote gastrulation? Here, we survey the literature on reptilian gastrulation and provide new data on Brachyury RNA and laminin protein expression in gastrula-stage turtle (Pelodiscus sinensis) embryos. We propose a model to reconcile the primitive streak-associated gastrulation in birds and the blastopore-associated gastrulation in extant reptiles. PMID:23157408

  3. Effect of Process Variables on the Formation of Streak Defects on Anodized Aluminum Extrusions: An Overview

    NASA Astrophysics Data System (ADS)

    Zhu, Hanliang; Couper, Malcolm J.; Dahle, Arne K.

    2012-04-01

    Streak defects are often present on anodized extrusions of 6xxx series aluminum alloys, increasing the fabrication cost of these products. Moreover, streaking often only becomes visible after etching and anodizing treatments, rather than in the as-extruded condition, making it difficult to identify the original causes and influencing factors of these defects. In this paper, various process variables that influence the formation of streak defects on anodized aluminium extrusions are reviewed on the basis of a literature review, industrial practice and experimental results. The influencing factors involved in various processing steps such as billet quality, extrusion process, die design and etching process are considered. Effective measures for preventing the formation of streak defects in industrial extrusion products are discussed.

  4. Yellow Fever: A Reemerging Threat

    PubMed Central

    Gardner, Christina L.; Ryman, Kate D.

    2014-01-01

    Yellow fever (YF) is a viral disease, endemic to tropical regions of Africa and the Americas. YF principally affects humans and nonhuman primates, and is transmitted via the bite of infected mosquitoes. The agent of YF, yellow fever virus (YFV), can cause devastating epidemics of potentially fatal, hemorrhagic disease. We rely on mass vaccination campaigns to prevent and control these outbreaks. However, the risk of major YF epidemics, especially in densely populated, poor urban settings, both in Africa and South America, has greatly increased due to: (1) reinvasion of urban settings by the mosquito vector of YF, Aedes aegypti; (2) rapid urbanization, particularly in parts of Africa, with populations shifting from rural to predominantly urban; and (3) waning immunization coverage. Consequently, YF is considered an emerging, or reemerging disease of considerable importance. PMID:20513550

  5. Split ring resonator based THz-driven electron streak camera featuring femtosecond resolution

    NASA Astrophysics Data System (ADS)

    Fabia?ska, Justyna; Kassier, Gnther; Feurer, Thomas

    2014-07-01

    Through combined three-dimensional electromagnetic and particle tracking simulations we demonstrate a THz driven electron streak camera featuring a temporal resolution on the order of a femtosecond. The ultrafast streaking field is generated in a resonant THz sub-wavelength antenna which is illuminated by an intense single-cycle THz pulse. Since electron bunches and THz pulses are generated with parts of the same laser system, synchronization between the two is inherently guaranteed.

  6. Split ring resonator based THz-driven electron streak camera featuring femtosecond resolution.

    PubMed

    Fabia?ska, Justyna; Kassier, Gnther; Feurer, Thomas

    2014-01-01

    Through combined three-dimensional electromagnetic and particle tracking simulations we demonstrate a THz driven electron streak camera featuring a temporal resolution on the order of a femtosecond. The ultrafast streaking field is generated in a resonant THz sub-wavelength antenna which is illuminated by an intense single-cycle THz pulse. Since electron bunches and THz pulses are generated with parts of the same laser system, synchronization between the two is inherently guaranteed. PMID:25010060

  7. Split ring resonator based THz-driven electron streak camera featuring femtosecond resolution

    NASA Astrophysics Data System (ADS)

    Fabia?ska, Justyna; Kassier, Gnther; Feurer, Thomas

    2015-03-01

    Through combined three-dimensional electromagnetic and particle tracking simulations we demonstrate a THz driven electron streak camera featuring a temporal resolution down to a femtosecond. The ultrafast streaking field is generated in a resonant THz sub-wavelength antenna, which is illuminated by an intense single-cycle THz pulse. Since electron bunches and THz pulses are generated by the same laser system, synchronization between the two is inherently guaranteed.

  8. Split ring resonator based THz-driven electron streak camera featuring femtosecond resolution

    PubMed Central

    Fabia?ska, Justyna; Kassier, Gnther; Feurer, Thomas

    2014-01-01

    Through combined three-dimensional electromagnetic and particle tracking simulations we demonstrate a THz driven electron streak camera featuring a temporal resolution on the order of a femtosecond. The ultrafast streaking field is generated in a resonant THz sub-wavelength antenna which is illuminated by an intense single-cycle THz pulse. Since electron bunches and THz pulses are generated with parts of the same laser system, synchronization between the two is inherently guaranteed. PMID:25010060

  9. Streak detection and analysis pipeline for space-debris optical images

    NASA Astrophysics Data System (ADS)

    Virtanen, Jenni; Poikonen, Jonne; Säntti, Tero; Komulainen, Tuomo; Torppa, Johanna; Granvik, Mikael; Muinonen, Karri; Pentikäinen, Hanna; Martikainen, Julia; Näränen, Jyri; Lehti, Jussi; Flohrer, Tim

    2016-04-01

    We describe a novel data-processing and analysis pipeline for optical observations of moving objects, either of natural (asteroids, meteors) or artificial origin (satellites, space debris). The monitoring of the space object populations requires reliable acquisition of observational data, to support the development and validation of population models and to build and maintain catalogues of orbital elements. The orbital catalogues are, in turn, needed for the assessment of close approaches (for asteroids, with the Earth; for satellites, with each other) and for the support of contingency situations or launches. For both types of populations, there is also increasing interest to detect fainter objects corresponding to the small end of the size distribution. The ESA-funded StreakDet (streak detection and astrometric reduction) activity has aimed at formulating and discussing suitable approaches for the detection and astrometric reduction of object trails, or streaks, in optical observations. Our two main focuses are objects in lower altitudes and space-based observations (i.e., high angular velocities), resulting in long (potentially curved) and faint streaks in the optical images. In particular, we concentrate on single-image (as compared to consecutive frames of the same field) and low-SNR detection of objects. Particular attention has been paid to the process of extraction of all necessary information from one image (segmentation), and subsequently, to efficient reduction of the extracted data (classification). We have developed an automated streak detection and processing pipeline and demonstrated its performance with an extensive database of semisynthetic images simulating streak observations both from ground-based and space-based observing platforms. The average processing time per image is about 13 s for a typical 2k-by-2k image. For long streaks (length >100 pixels), primary targets of the pipeline, the detection sensitivity (true positives) is about 90% for both scenarios for the bright streaks (SNR > 1), while in the low-SNR regime, the sensitivity is still 50% at SNR = 0.5 .

  10. A strain of Clover yellow vein virus that causes severe pod necrosis disease in snap bean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2000, the soybean aphid (Aphis glycines) has been associated with severe virus epidemics in snap bean (Phaseolus vulgaris) in the upper Midwestern states, New York, and Ontario, Canada. The causal agent of a disease causing severe mosaic, apical necrosis stunting and extensive pod necrosis wa...

  11. Influence of harvest timing, fungicides, and Beet Necrotic Yellow Vein Virus on sugar beet storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Root rots in sugar beet storage can lead to million dollar losses because of reduced sucrose recovery. Thus, studies were conducted to establish better chemical control options and a better understanding of the fungi involved in the rot complex. A water check and three fungicides (Mertect, Propuls...

  12. Symptoms and distribution of Squash vein yellowing virus in vining cucurbits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The distribution of SqVYV in cucurbit species other than watermelon is unknown. Virus distribution and symptoms of vining cucurbit species were determined by nucleic acid tissue blots and PCR. Comparisons of virus distribution between these cucurbits and watermelon are made....

  13. Semipersistent whitefly transmission of Squash vein yellowing virus, causal agent of viral watermelon vine decline

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of experiments were completed to determine efficiency of transmission, effects of different acquisition and inoculation access periods, the length of time that whiteflies retained transmissible virus, and the minimum time needed to complete a cycle of acquisition and inoculation for SqVYV. ...

  14. Rhizosphere mycoflora of healthy and yellow vein mosaic virus infected okra (Abelmoschus esculentus) plants.

    PubMed

    Singh, S J; Tewari, R P

    1979-01-01

    Investigations on the rhizosphere mycoflora of healthy and virus (YVMV) infected okra plants showed a higher fungal population in the rhizosphere of healthy plants at preflowering and post-flowering stages than in that of diseased ones. Maximum population was observed during flowering both in healthy and diseased plant rhizosphere as well as in non-rhizosphere soil. However, virus infected plants showed a higher population at the flowering stage than healthy ones. The quantitative differences in the rhizosphere of healthy and diseased plants during flowering seem to be due to a change in C/N ratio and amino acids. The drastic reduction in diseased plant rhizospheres during the post-flowering stage may be due to either change in C/N ratio unfavourable to mycoflora or production of some toxic substances inhibiting multiplication of the mycoflora. PMID:94749

  15. Two new virus diseases in Rubus: Blackberry yellow vein and raspberry crumbly fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackberry production area has increased dramatically in the Southeast in recent years with the release of new cultivars suitable for the region and due to elevated customer demand for high quality fruit, which has led to high prices enjoyed by the growers. As in almost all cases where a crop is int...

  16. Normal distal pulmonary vein anatomy

    PubMed Central

    Klimek-Piotrowska, Wies?awa; Pi?tek, Katarzyna; Koziej, Mateusz; Ho?da, Jakub

    2016-01-01

    Background. It is well known that the pulmonary veins (PVs), especially their myocardial sleeves play a critical role in the initiation and maintenance of atrial fibrillation. Understanding the PV anatomy is crucial for the safety and efficacy of all procedures performed on PVs. The aim of this study was to present normal distal PV anatomy and to create a juxtaposition of all PV ostium variants. Methods. A total of 130 randomly selected autopsied adult human hearts (Caucasian) were examined. The number of PVs ostia was evaluated and their diameter was measured. The ostium-to-last-tributary distance and macroscopic presence of myocardial sleeves were also evaluated. Results. Five hundred forty-one PV ostia were identified. Four classical PV ostia patterns (two left and two right PVs) were observed in 70.8% of all cases. The most common variant was the classical pattern with additional middle right PV (19.2%), followed by the common ostium for the left superior and the inferior PVs (4.44%). Mean diameters of PV ostia (for the classical pattern) were: left superior = 13.8 2.9 mm; left inferior = 13.3 3.4 mm; right superior = 14.3 2.9 mm; right inferior = 13.7 3.3 mm. When present, the additional middle right PV ostium had the smallest PV ostium diameter in the heart (8.2 4.1 mm). The mean ostium-to-last-tributary (closest to the atrium) distances were: left superior = 15.1 4.6 mm; left inferior = 13.5 4.0 mm; right superior = 11.8 4.0 mm; right inferior = 11.0 3.7 mm. There were no statistically significant differences between sexes in ostia diameters and ostium-to-last-tributary distances. Conclusion. Only 71% of the cases have four standard pulmonary veins. The middle right pulmonary vein is present in almost 20% of patients. Presented data can provide useful information for the clinicians during interventional procedures or radiologic examinations of PVs. PMID:26793429

  17. Normal distal pulmonary vein anatomy.

    PubMed

    Klimek-Piotrowska, Wies?awa; Ho?da, Mateusz K; Pi?tek, Katarzyna; Koziej, Mateusz; Ho?da, Jakub

    2016-01-01

    Background. It is well known that the pulmonary veins (PVs), especially their myocardial sleeves play a critical role in the initiation and maintenance of atrial fibrillation. Understanding the PV anatomy is crucial for the safety and efficacy of all procedures performed on PVs. The aim of this study was to present normal distal PV anatomy and to create a juxtaposition of all PV ostium variants. Methods. A total of 130 randomly selected autopsied adult human hearts (Caucasian) were examined. The number of PVs ostia was evaluated and their diameter was measured. The ostium-to-last-tributary distance and macroscopic presence of myocardial sleeves were also evaluated. Results. Five hundred forty-one PV ostia were identified. Four classical PV ostia patterns (two left and two right PVs) were observed in 70.8% of all cases. The most common variant was the classical pattern with additional middle right PV (19.2%), followed by the common ostium for the left superior and the inferior PVs (4.44%). Mean diameters of PV ostia (for the classical pattern) were: left superior = 13.8 2.9 mm; left inferior = 13.3 3.4 mm; right superior = 14.3 2.9 mm; right inferior = 13.7 3.3 mm. When present, the additional middle right PV ostium had the smallest PV ostium diameter in the heart (8.2 4.1 mm). The mean ostium-to-last-tributary (closest to the atrium) distances were: left superior = 15.1 4.6 mm; left inferior = 13.5 4.0 mm; right superior = 11.8 4.0 mm; right inferior = 11.0 3.7 mm. There were no statistically significant differences between sexes in ostia diameters and ostium-to-last-tributary distances. Conclusion. Only 71% of the cases have four standard pulmonary veins. The middle right pulmonary vein is present in almost 20% of patients. Presented data can provide useful information for the clinicians during interventional procedures or radiologic examinations of PVs. PMID:26793429

  18. Retracted manuscript: Scientific yellow journalism.

    PubMed

    2013-01-01

    The following article from Small GTPases, "Scientific Yellow Journalism" by Anica Klockars and Michael J. Williams, published online on 20 September 2012 (doi: 10.4161/sgtp.22289; http://www.landesbioscience.com/journals/smallgtpases/article/22289/) by Landes Bioscience and subsequently published in print in Small GTPases 2012 3(4):201 has been retracted by agreement between the authors and the journal's Editor in Chief, Michael J. Williams (also an author of the paper). PMID:23485921

  19. Complete nucleotide sequence of rose yellow mosaic virus, a novel member of the family Potyviridae.

    PubMed

    Mollov, Dimitre; Lockhart, Ben; Zlesak, David

    2013-09-01

    The complete genomic sequence of rose yellow mosaic virus (RoYMV) was determined and found to have all the features that are characteristic of members of the family Potyviridae. The RoYMV genome is 9508 nucleotides long excluding the 3'-poly-(A) tail and contains a single open reading frame encoding a polyprotein of 3067 amino acids. The RoYMV P3 and CI cistrons are shorter than those of other members of the family Potyviridae, and the 6K1 cistron is completely absent. Comparative sequence analysis revealed that RoYMV had highest amino acid sequence identity across the entire genome sequence to brome streak mosaic virus (33%) and to turnip mosaic virus (30%) at the coat protein level. Based on its low sequence similarity to known members of the family Potyviridae and phylogenetic analysis, RoYMV appears to be a distinct, previously undescribed, member of this family. PMID:23553457

  20. New observations of Bolivian wind streaks by JPL Airborne SAR: Preliminary results

    NASA Technical Reports Server (NTRS)

    Blumberg, Dan G.; Greeley, Ronald

    1995-01-01

    In 1993 NASA's Jet Propulsion Laboratory Airborne Synthetic Aperture Radar system (AIRSAR) was deployed to South America to collect multi-parameter radar data over pre-selected targets. Among the sites targeted was a series of wind streaks located in the Altiplano of Bolivia. The objective of this investigation is to study the effect of wavelength, polarization, and incidence angle on the visibility of wind streaks in radar data. Because this is a preliminary evaluation of the recently acquired data we will focus on one scene and, thus, only on the effects of wavelength and polarization. Wind streaks provide information on the near-surface prevailing winds and on the abundance of winderodible material, such as sand. The potential for a free-flyer radar system that could provide global radar images in multiple wavelengths, polarizations, and incidence angles requires definition of system parameters for mission planning. Furthermore, thousands of wind streaks were mapped from Magellan radar images of Venus; their interpretation requires an understanding of the interaction of radar with wind streaks and the surrounding terrain. Our experiment was conducted on wind streaks in the Altiplano of Bolivia to address these issues.

  1. Effects of Hot Streak Shape on Rotor Heating in a High-Subsonic Single-Stage Turbine

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel J.; Gundy-Burlet, Karen L.; Norvig, Peter (Technical Monitor)

    1999-01-01

    Experimental data have shown that combustor temperature non-uniformities can lead to the excessive heating of first-stage rotor blades in turbines. This heating of the rotor blades can lead to thermal fatigue and degrade turbine performance. The results of recent studies have shown that variations in the circumferential location (clocking) of the hot streak relative to the first-stage vane airfoils can be used to minimize the adverse effects of the hot streak. The effects of the hot streak/airfoil count ratio on the heating patterns of turbine airfoils have also been evaluated. In the present investigation, three-dimensional unsteady Navier-Stokes simulations have been performed for a single-stage high-pressure turbine operating in high subsonic flow. In addition to a simulation of the baseline turbine, simulations have been performed for circular and elliptical hot streaks of varying sizes in an effort to represent different combustor designs. The predicted results for the baseline simulation show good agreement with the available experimental data. The results of the hot streak simulations indicate: that a) elliptical hot streaks mix more rapidly than circular hot streaks, b) for small hot streak surface area the average rotor temperature is not a strong function of hot streak temperature ratio or shape, and c) hot streaks with larger surface area interact with the secondary flows at the rotor hub endwall, generating an additional high temperature region.

  2. Applications of the streak seeding technique in protein crystallization

    NASA Astrophysics Data System (ADS)

    Stura, Enrico A.; Wilson, Ian A.

    1991-03-01

    The seeding of protein solutions is a powerful method for growing crystals. Microseeding and macroseeding both require conditions under which spontaneous nucleation is totally absent or extremely rare. A technique where seeds from a crystal are streaked into a protein-precipitant drop along a straight line using a rabbit whisker has been developed to determine suitable conditions for either micro- or macro-seeding. This seeding technique has also been successful in obtaining crystals using crystalline precipitate as the source of seeds, in cross-seeding from Fabpeptide complex crystals to obtain complexes with peptides of longer length, and similarly in cross-seeding from crystals of one monoclonal Fabpeptide complex to obtain crystals of a different monoclonal Fab complexed to the same peptide. This relatively simple technique should be of general applicability in macromolecular crystallizations and offers the potential to test whether new complex crystals mey be obtained by seeding with the native or other complexes, to determine whether cross-seeding may be used with seeds from a related protein or to analyze the crystallization potential of different protein preparations.

  3. Intial synchroscan streak camera imaging at the A0 photoinjector

    SciTech Connect

    Lumpkin, A.H.; Ruan, J.; /Fermilab

    2008-04-01

    At the Fermilab A0 photoinjector facility, bunch-length measurements of the laser micropulse and the e-beam micropulse have been done in the past with a single-sweep module of the Hamamatsu C5680 streak camera with an intrinsic shot-to-shot trigger jitter of 10 to 20 ps. We have upgraded the camera system with the synchroscan module tuned to 81.25 MHz to provide synchronous summing capability with less than 1.5-ps FWHM trigger jitter and a phase-locked delay box to provide phase stability of {approx}1 ps over 10s of minutes. This allowed us to measure both the UV laser pulse train at 244 nm and the e-beam via optical transition radiation (OTR). Due to the low electron beam energies and OTR signals, we typically summed over 50 micropulses with 1 nC per micropulse. We also did electron beam bunch length vs. micropulse charge measurements to identify a significant e-beam micropulse elongation from 10 to 30 ps (FWHM) for charges from 1 to 4.6 nC. This effect is attributed to space-charge effects in the PC gun as reproduced by ASTRA calculations. Chromatic temporal dispersion effects in the optics were also characterized and will be reported.

  4. Polar Dunes In Summer Exhibit Frost Patches, Wind Streaks

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mars Global Surveyor passes over the north polar region of the red planet twelve times each day, offering many opportunities to observe how the polar cap frosts and dunes are changing as the days goby. Right now it is summer in the north. This picture, taken the second week of April 1999, shows darks and dunes and remnant patches of bright frost left over from the winter that ended in July 1998. Dark streaks indicate recent movement of sand. The picture covers an area only 1.4 kilometers (0.9 miles)across and is illuminated from the upper right.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  5. Pedestal Craters and Wind Streaks, South Medusae Fossae

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mars is a desert planet in which wind has a considerable effect on the landscape. Bright and dark wind streaks in this image indicate past movement of fine sediment across the landscape from upper left toward lower right. Two impact craters that look like flowers or starfish are seen in the lower portion of the image. The ejecta deposits of these craters are raised above the surrounding terrain, and indicate that wind has deflated a layer of material (that is, blown it away, thus lowering the surface) that was present at the time that the craters formed. The craters were formed by impacts of meteorites into the earlier, higher surface, and the rocks and gravel thrown out when they formed protected some of this former layer from the wind's effects. This picture--showing part of the Medusae Fossae region near the martian equator--was taken in early April 1999 and covers an area only 1 kilometer (0.62 miles)wide. Illumination is from the lower right.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  6. Enhancing the contrast of subcutaneous veins

    NASA Astrophysics Data System (ADS)

    Zeman, Herbert D.; Lovhoiden, Gunnar

    1999-07-01

    A technique for enhancing the contrast of subcutaneous veins has been demonstrated. This technique uses a near infrared light source and one or more infrared sensitive CCD TV cameras to produce a contrast enhanced image of the subcutaneous veins. This video image of the veins is projected back onto the patient's skin using an LCD vein projector. The use of an infrared transmitting filter in front of the video cameras prevents any positive feedback from the visible light from the video projector from causing instabilities in the projected image. The demonstration contrast enhancing illuminator has been tested on adults, both Caucasian and African-American, and it enhances veins quite well in most cases. Preliminary studies on a 9 month old girl indicate promise for pediatric use.

  7. Preduodenal portal vein in the adult.

    PubMed

    Papaziogas, T; Papaziogas, B; Paraskevas, G; Lazaridis, C; Patsas, A

    2000-09-01

    We present three cases of preduodenal portal vein in adult people, which were diagnosed in our department. All of them were identified during elective operation for cholelithiasis, caused some technical difficulties to the performance of the operation, but led to no major intraoperative or postoperative complications. None of them had any preoperative symptoms, which could be related to this anomaly. The preduodenal portal vein is a rare congenital anomaly, which is usually discovered in infants or children due to the obstruction of the duodenum. In adults, it is often asymptomatic, and is usually discovered as an accidental finding during laparotomy for other reason. The postcontrast CT can set the diagnosis, when this anomaly is suspected. Despite its rarity, this anomaly is of great surgical importance, because it can predispose to intraoperative complications including hemorrhage from the abnormal vein, or damage to the biliary tract or the distented duodenum. The anterior position of the portal vein results from the persistence of the ventral anastomosis between the two vitelline veins and the distal portion of the right vitelline vein, with subsequent atrophy of the cranial part of the left vitelline and dorsal anastomotic vein. PMID:11244931

  8. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it extends into an impact crater. ?? 2009 Elsevier B.V.

  9. Mars Eolian Geology at Airphoto Scales: The Large Wind Streaks of Western Arabia Terra

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2001-01-01

    More than 27,000 pictures at aerial photograph scales (1.5-12 m/pixel) have been acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) since September 1997. The pictures are valuable for testing hypotheses about geologic history and processes of Mars. Of particular interest are eolian features connected to surface albedo patterns. This work is focused on low-albedo wind streaks, some over 100 km long, in western Arabia Terra. Each streak is widest where it originates at an impact crater (typically 25-150 km diameter). The streaks taper downwind. Within the associated craters there is a lower-albedo surface that, in nearly all observed cases, includes barchan dunes indicative of transport in the same direction as the wind streaks. Upwind of the dunes there is usually an outcrop of layered material that might have served as a source for dune sand. MOC images show that the west Arabia streaks consist of a smooth-surfaced, multiple-meters-thick, mantle (smooth at 1.5 m/pixel) that appears to be superposed on local surfaces. No dunes are present, indicating that down-streak transport of sediment via saltation and traction have not occurred. Two models might explain the observed properties: (1) the streaks consist of dark silt- and clay-sized grains deflated from the adjacent crater interiors and deposited from suspension or (2) they are remnants (protected in the lee of impact crater rims) of a formerly much larger, regional covering of low albedo, smooth-surfaced mantle. The latter hypothesis is based on observation of low albedo mantled surfaces occurring south of west Arabia in Terra Meridiani. For reasons yet unknown, a large fraction of the martian equatorial regions are covered by low albedo, mesa-forming material that lies unconformably atop eroded layered and cratered terrain. Both hypotheses are being explored via continued selective targeting of new MOC images as well as analyses of the new data.

  10. Molecular characterization and pathogenicity of tomato yellow leaf curl virus in China.

    PubMed

    Zhang, Hui; Gong, Huanran; Zhou, Xueping

    2009-10-01

    Several tomato production regions in China were surveyed for tomato yellow leaf curl disease (TYLCD), and 31 tomato leaf samples showing TYLCD-like symptoms were collected. The partial or full-length genomes of these isolates were sequenced and tomato yellow leaf curl virus (TYLCV) was detected in Shanghai, Zhejiang, Jiangsu Shandong and Hebei provinces of China. The TYLCV isolates found in China share high sequence identity ([98%) and have more than 97% sequence identity with TYLCVIL[ IL:Reo] (X15656). Phylogenetic relationship analysis reveals that although with little genetic variability, they can form two groups and all the TYLCV isolates in China belong to the group I. An infectious clone of TYLCV-[CN:SH2] (AM282874) was constructed and agro-inoculated into Nicotiana benthamiana, N. tabacum Samsun, N. glutinosa, Solanum lycopersicum, Petunia hybrida, Cucumis sativus, Gossypium hirsutum, S. melongena, and Capsicum annuum. TYLCV-[CN:SH2] can induce severe leaf curling and stunting symptoms in these plants except C. sativus, G. hirsutum, S. melongena and C. annuum.We verified that TYLCV can trans-replicate tomato yellow leaf curl China virus DNA-b in N. benthamiana and S. lycopersicum and induced more severe symptoms with distortion and yellow vein. PMID:19590945

  11. Tie-dyed2 Encodes a Callose Synthase That Functions in Vein Development and Affects Symplastic Trafficking within the Phloem of Maize Leaves12[C][W][OA

    PubMed Central

    Slewinski, Thomas L.; Baker, R. Frank; Stubert, Adam; Braun, David M.

    2012-01-01

    The tie-dyed2 (tdy2) mutant of maize (Zea mays) displays variegated green and yellow leaves. Intriguingly, the yellow leaf tissues hyperaccumulate starch and sucrose, the soluble sugar transported long distance through the phloem of veins. To determine the molecular basis for Tdy2 function, we cloned the gene and found that Tdy2 encodes a callose synthase. RNA in situ hybridizations revealed that in developing leaves, Tdy2 was most highly expressed in the vascular tissue. Comparative expression analysis with the vascular marker maize PINFORMED1a-yellow fluorescent protein confirmed that Tdy2 was expressed in developing vein tissues. To ascertain whether the defect in tdy2 leaves affected the movement of sucrose into the phloem or its long-distance transport, we performed radiolabeled and fluorescent dye tracer assays. The results showed that tdy2 yellow leaf regions were defective in phloem export but competent in long-distance transport. Furthermore, transmission electron microscopy of tdy2 yellow leaf regions showed incomplete vascular differentiation and implicated a defect in cell-to-cell solute movement between phloem companion cells and sieve elements. The disruption of sucrose movement in the phloem in tdy2 mutants provides evidence that the Tdy2 callose synthase functions in vascular maturation and that the vascular defects result in impaired symplastic trafficking into the phloem translocation stream. PMID:22932757

  12. Tie-dyed2 encodes a callose synthase that functions in vein development and affects symplastic trafficking within the phloem of maize leaves.

    PubMed

    Slewinski, Thomas L; Baker, R Frank; Stubert, Adam; Braun, David M

    2012-11-01

    The tie-dyed2 (tdy2) mutant of maize (Zea mays) displays variegated green and yellow leaves. Intriguingly, the yellow leaf tissues hyperaccumulate starch and sucrose, the soluble sugar transported long distance through the phloem of veins. To determine the molecular basis for Tdy2 function, we cloned the gene and found that Tdy2 encodes a callose synthase. RNA in situ hybridizations revealed that in developing leaves, Tdy2 was most highly expressed in the vascular tissue. Comparative expression analysis with the vascular marker maize PINFORMED1a-yellow fluorescent protein confirmed that Tdy2 was expressed in developing vein tissues. To ascertain whether the defect in tdy2 leaves affected the movement of sucrose into the phloem or its long-distance transport, we performed radiolabeled and fluorescent dye tracer assays. The results showed that tdy2 yellow leaf regions were defective in phloem export but competent in long-distance transport. Furthermore, transmission electron microscopy of tdy2 yellow leaf regions showed incomplete vascular differentiation and implicated a defect in cell-to-cell solute movement between phloem companion cells and sieve elements. The disruption of sucrose movement in the phloem in tdy2 mutants provides evidence that the Tdy2 callose synthase functions in vascular maturation and that the vascular defects result in impaired symplastic trafficking into the phloem translocation stream. PMID:22932757

  13. Titanium exposure and yellow nail syndrome

    PubMed Central

    Ataya, Ali; Kline, Kristopher P.; Cope, Jessica; Alnuaimat, Hassan

    2015-01-01

    Yellow nail syndrome is a rare disease of unclear etiology. We describe a patient who develops yellow nail syndrome, with primary nail and sinus manifestations, shortly after amalgam dental implants. A study of the patient's nail shedding showed elevated nail titanium levels. The patient had her dental implants removed and had complete resolution of her sinus symptoms with no change in her nail findings. Since the patient's nail findings did not resolve we do not believe titanium exposure is a cause of her yellow nail syndrome but perhaps a possible relationship exists between titanium exposure and yellow nail syndrome that requires further studies. PMID:26744684

  14. Effect of Yellow Filters on the Vision

    NASA Astrophysics Data System (ADS)

    Slica, S.; Ikaunieks, G.; Rinkus, D.

    2010-03-01

    In the literature, controversial information could be found whether the yellow filters may improve the quality of vision. To find out what is the effect of yellow filters on the quality of vision, 27 individuals were examined for the contrast sensitivity using the Pelli-Robson chart, under normal (photopic) and reduced (mesopic) illumination. The measurements were carried out with and without yellow filters (light transmission 67%, measured with an Ocean Optic spectrometer). Also, the measurements were taken using a grey filter with transmission close to that of the yellow filter (73%). The results did not show statistically significant improvement when looking through yellow filters. However, 56% of the individuals asserted that under reduced illumination they found it more agreeable to look through yellow filters. Two persons were extra tested for low contrast visual acuity using a computerized test and objective measurements by the visual evoked potentials (VEP) method. These visual measurements also did not show statistically significant improvement of the visual contrast sensitivity when yellow filters were used. Our measurements do not confirm the data found in literature about the vision improvement owing to yellow filters. However, the mentioned above subjective improvement at using yellow filters in mesopic conditions shows that under very low illumination such filters may slightly increase the visual quality.

  15. Marrow: red, yellow and bad.

    PubMed

    Guillerman, Robert Paul

    2013-03-01

    Bone marrow is one of the largest and most dynamic tissues in the body, and it is well-depicted on conventional MRI sequences. However, often only perfunctory attention is paid to the bone marrow on musculoskeletal imaging studies, raising the risk of delayed or missed diagnoses. To guide appropriate recognition of normal variants and pathological processes involving the marrow compartment, this article describes and depicts the physiological spatiotemporal pattern of conversion of hematopoietic red marrow to fatty yellow marrow during childhood and adolescence, and the characteristic imaging findings of disorders involving marrow hyperplasia/reconversion, marrow infiltration/deposition and marrow depletion/failure. PMID:23478934

  16. Yellow metal for sour service

    SciTech Connect

    Clark, T.; Inglis, W.; Fowler, C.M.

    1996-04-01

    UNS C69100, a yellow metal copper-based alloy, is used extensively in the European oil and gas industry. A series of sour environmental tests was conducted at ambient temperature and at elevated temperature and pressure. The ambient temperature tests indicated high resistance to sulfide stress corrosion cracking (SSCC). Additionally, tests including free sulfur exhibited no evidence of cracking. The high temperature and pressure tests also showed no tendency for SSCC. The corrosion rate tests at ambient temperature indicated corrosion rates well below those of carbon steel tested in an identical environment. Hydrogen permeation measurements confirmed the corrosion rate measurements. This alloy should be considered for sour service use.

  17. [FEATURES LIVER TRANSPLANTATION IN PORTAL VEIN THROMBOSIS].

    PubMed

    Abbasov, P A

    2015-07-01

    In 2012 - 2013 years in 265 patients for liver transplantation was performed, including in 224 (84.5%)--from a living donor, in 41 (15.5%)--from the dead body. Using a Foley catheter to stop bleeding, and the imposition of vascular sutures during endovenectomy in portal vein thrombosis (PVT) and its possible damage under all conditions. In particular, PVT IV degree (Grade IV) in order to restore blood flow in the graft using the left gastric and renal vein is an alternative, if they are cryopreserved vein may be suitably used. PMID:26591211

  18. Cardiac vein angioplasty for biventricular pacing.

    PubMed

    Sandler, David A; Feigenblum, David Y; Bernstein, Neil E; Holmes, Douglas S; Chinitz, Larry A

    2002-12-01

    Biventricular pacing for the treatment of congestive heart failure has consistently demonstrated improvement in quality-of-life and reduction in heart failure symptoms. Though the over-the-wire systems will be helpful in overcoming many existing obstacles to optimal lead placement, anatomic variability will still limit overall success. Cardiac vein angioplasty may be required for deployment of leads into tortuous or obstructed cardiac veins. This case report describes the angioplasty of a focal cardiac vein stenosis allowing for successful implantation of a left ventricular pacing lead. The safety of this procedure is unknown, though the risks may be acceptable in certain patients. PMID:12520686

  19. Selecting a treatment for primary varicose veins.

    PubMed Central

    Tremblay, J; Lewis, E W; Allen, P T

    1985-01-01

    The treatment of varicose veins includes injection/compression sclerotherapy and surgical stripping or ligation or both. Surgery appears to be favoured when the saphenous system is involved or when the patient is 35 to 64 years old or presents with ankle edema or flare. On the other hand, sclerotherapy has been found to be more effective in patients with dilated superficial veins or incompetent perforating veins in the lower legs and to be more acceptable and less expensive than surgical treatment. PMID:3891060

  20. An Optical Streaking Method for Measuring Femtosecond Electron Bunches

    SciTech Connect

    Ding, Yuantao; Bane, Karl L.F.; Huang, Zhirong; /SLAC

    2011-12-14

    The measurement of the ultra-short electron bunch length on the femtosecond time scale constitutes a very challenging problem. In the x-ray free electron laser facilities such as the Linac Coherent Light Source, generation of a sub-ten femtoseconds electron beam with 20pC charge is possible, but direct measurements are very difficult due to the resolution limit of the present diagnostics. We propose a new method here based on the measurement of the electron beam energy modulation induced from laser-electron interaction in a short wiggler. A typical optical streaking method requires a laser wavelength much longer than the electron bunch length. In this paper a laser with its wavelength shorter than the electron bunch length has been adopted, while the slope on the laser intensity envelope is used to distinguish the different periods. With this technique it is possible to reconstruct the bunch longitudinal profile from a single shot measurement. Generation of ultrashort x-ray pulses at femtoseconds (fs) scale is of great interest within synchrotron radiation and free electron laser (FEL) user community. One of the simple methods is to operate the FEL facility at low charge. At the Linac Coherent Light Source (LCLS), we have demonstrated the capability of generating ultrashort electron-beam (e-beam) with a duration of less than 10 fs fwhm using 20 pC charge. The x-ray pulses have been delivered to the x-ray users with a similar or even shorter pulse duration. However, The measurement of such short electron or x-ray pulse length at the fs time-scale constitutes a challenging problem. A standard method using an S-band radio-frequency (rf) transverse deflector has been established at LCLS, which works like a streak camera for electrons and is capable of resolving bunch lengths as short as 25 fs fwhm. With this device, the electrons are transversely deflected by the high-frequency time-variation of the deflecting fields. Increasing the deflecting voltage and rf frequency are the right direction to achieve a better resolution. For example, by choosing an X-band transverse deflecting cavity, the expected resolution for LCLS beam with 4.3 GeV is about 1 fs rms. Typically the rf breakdown threshold and the power source availability prevent going to even higher voltage and frequency. With the highly-developed laser techniques, we can choose to streak the beam at optical frequencies. By jumping from rf to optical frequency, the wavelength is shortening by 4 to 5 orders. With an electron bunch length shorter than half period of the laser, we can apply the similar rf deflecting or zero-phasing method for e-beam bunch length measurements using a high-power laser. A short wiggler is required to provide interaction between the electron and the laser. For example, to measure the e-beam at the order of 1 m rms length, a laser with its wavelength of 10 {mu}m may be considered. For a typical few GeV e-beam, the wiggler period has to be large to satisfy the resonance condition. Also, if the e-beam is longer than one laser period, the different modulation periods will overlap and we cannot distinguish them. So this method is so far limited by the achievable long-wavelength laser power. To get an effective modulation on an e-beam of 4.3 GeV, the required laser power is about a few tens GW. In this paper we propose to adopt a high-power Ti:Sapphire laser (wavelength of 800 nm), and use the slope in the intensity envelope to distinguish the different modulation periods. First an ultrashort electron beam interacts with the Ti:Sapphire laser in a wiggler, where the electron energy is modulated at the same periods of the laser. If the laser pulse is long and the short electron bunch is overlapped (in time) with the middle part of the laser, such as the setup at LCLS laser heater, the different energy modulation periods on the electron beam will be overlapped on the energy profile. In this conditionwe typically have a double-horn distribution of the energy profile, and the electron-bunch length information cannot be retrieved. But if the laser pulse (

  1. Hand vein recognition based on orientation of LBP

    NASA Astrophysics Data System (ADS)

    Bu, Wei; Wu, Xiangqian; Gao, Enying

    2012-06-01

    Vein recognition is becoming an effective method for personal recognition. Vein patterns lie under the skin surface of human body, and hence provide higher reliability than other biometric traits and hard to be damaged or faked. This paper proposes a novel vein feature representation method call orientation of local binary pattern (OLBP) which is an extension of local binary pattern (LBP). OLBP can represent the orientation information of the vein pixel which is an important characteristic of vein patterns. Moreover, the OLBP can also indicate on which side of the vein centerline the pixel locates. The OLBP feature maps are encoded by 4-bit binary values and an orientation distance is developed for efficient feature matching. Based on OLBP feature representation, we construct a hand vein recognition system employing multiple hand vein patterns include palm vein, dorsal vein, and three finger veins (index, middle, and ring finger). The experimental results on a large database demonstrate the effectiveness of the proposed approach.

  2. Flesh color inheritance and gene interactions among canary yellow, pale yellow and red watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two loci, C and i-C were previously reported to determine flesh color between canary yellow and red watermelon. Recently LCYB was found as a color determinant gene for canary yellow (C) and co-dominant CAPS marker was developed to identify canary yellow and red alleles. Another report suggested th...

  3. Commercial yellow sticky strips more attractive than yellow boards to western cherry fruit fly (Dipt., Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bright yellow sticky rectangles made of paper boards were previously identified as the most effective traps for capturing western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae). Thin rectangular sheets of yellow plastic allow higher light passage than yellow boards and may b...

  4. [Yellow fever epidemiology in Brazil].

    PubMed

    Mondet, B

    2001-08-01

    We have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in Brazil from 1954 to 1972 and especially from 1973 to 1999. This study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. The endemic area is located within the Amazon basin; here cases are scattered and generally limited in number. However, there are also "foci of endemic emergence" within this area, where cases are less rare, although occurrence remains irregular. The epidemic area is for the most part situated outside the Amazon basin, to the north east and particularly to the south. It has been divided into two parts according to whether the occurrence of yellow fever is cyclic or sporadic. The epidemics, which are all sylvatic, follow either a circular path (in the forest area) or a linear path (in forest-galleries of the savannah area). The study of the development of the 3 main epidemics (1972-74; 1979-82; 1986-92) in the cyclic emergence area showed that, on each occasion, the yellow fever virus appeared at a particularly active outbreak site located in the "serra dos Carajás", and from there, it followed the courses of the Tocantins and Araguaia rivers upstream, moving southwards during the "pre-epidemic phase" which may be visible due to the occurrence of a few cases, or may remain invisible. Subsequently the virus reached the emergence area, where it appeared in the form of epidemics. In this zone, it also followed privileged south-western pathways, moving from one hydraulic basin to another along the upstream courses of the rivers. Almost exactly the same pathways have been identified for each of the 3 epidemics studied. The distances travelled by the virus over a period of one year--when it goes rapidly--can reach several hundred kilometers. On the other hand, it may be stationary for a period of one or two consecutive years, occasionally three, remaining present in the area but infecting humans only rarely if at all. The virus occasionally leaves the cyclic emergence area and appears in the sporadic emergence area to the east, in the states of Bahia, Minas Gerais and São Paulo, and, as a consequence, moving onto other hydraulic basins. The small river basins in Maranhão and NorthWest states, as well as in the northern part of the state of Roraima also form part of the sporadic emergence area. The epidemics that occur here are directly linked to the endemic area and are only preceded by sometimes indiscernible epizootics and can consequently not be foreseen. Again the virus appears to use privileged pathways to reach the sporadic emergence areas where human and monkey populations are generally only partially immunised against yellow fever and where contact with mosquitoes is intense despite the fact it is limited in space and time, being restricted to the often narrow strip of trees along the water courses. Other routes used by the virus may be the Madeira, Xingu and Tapajós rivers, the scene of outbreaks observed in the state of Rondônia and in the north of Mato Grosso, where ongoing environmental changes are likely to result in an increasing number of outbreaks in the coming years. Since the discovery of the sylvatic cycle of yellow fever in 1933, not only the extent of the epidemiological areas has changed, but also their limits. Ecological modifications that are currently taking place in the Amazon basin, which is an endemic reservoir of the virus, will inevitably facilitate an increase the contact between humans and vectors. While more and more urban areas harbour populations of Aedes aegypti, the domestic and urban vector of yellow fever, it is particularly important to try to protect human populations living in emergence zones and epidemic areas and thus to prevent the arrival of the virus in towns via humans with viremia--in other words the much feared urbanisation of yellow fever in Brazil. PMID:11681224

  5. Gastric reddish streaks in the intact stomach: endoscopic feature of reactive gastropathy.

    PubMed

    Chen, Tseng-Shing; Li, Anna Fen-Yau; Chang, Full-Young

    2010-04-01

    The pathogenesis of reddish streaks in the intact stomach is unclear. Sixty-three functional dyspeptic patients with gastric reddish streaks were recruited for the study. Fifty-five patients (group I) had only reddish streaks while nine patients (group II) had additional lesions such as reddish patches or spots randomly scattered throughout the stomach. Updated Sydney system and parameters of reactive gastropathy were used to score the biopsy specimens from reddish streaks separately. Helicobacter pylori infection rate was found to be markedly lower in group I than group II patients (13% vs 89%, P < 0.001). H. pylori-infected patients had higher scores for acute and chronic inflammation (P < 0.001) and foveolar hyperplasia (P < 0.005) than non-infected patients, while other parameters for gastritis and gastropathy were similar between infected and non-infected patients. In H. pylori-non-infected patients all biopsy specimens had at least one histological feature of reactive gastropathy. Bile reflux was observed in 54% of patients (34/63). Only 7.9% used non-steroidal anti-inflammatory drugs and 4.9% drank alcohol. The present data indicate that the fundamental histological features of gastric reddish streaks are reactive gastropathy with low H. pylori infection, and are probably enterogastric reflux related in etiology. Coincidental H. pylori infection increased acute and chronic inflammatory cell infiltration, and enhanced the grade of foveolar hyperplasia. PMID:20403032

  6. Time delays for attosecond streaking in photo-ionization of neon

    NASA Astrophysics Data System (ADS)

    Feist, Johannes; Zatsarinny, Oleg; Nagele, Stefan; Pazourek, Renate; Burgdörfer, Joachim; Guan, Xiaoxu; Bartschat, Klaus; Schneider, Barry

    2014-05-01

    Time-resolved photoemission in neon atoms as probed by attosecond streaking has been of much interest and debate. We compute streaking time shifts for the emission of 2p and 2s electrons and their relative delay and compare with recent experimental data by Schultze et al. [Science 328, 1658 (2010)]. We employ the B-spline R-matrix method to calculate accurate Eisenbud-Wigner-Smith time delays from the multielectron dipole transition matrix elements for photoionization. The laser field-induced time shifts in the exit channel are obtained from separate, time-dependent simulations of a full streaking process by solving the time-dependent Schrödinger equation on the single-active-electron level. The resulting relative streaking time shifts between 2s and 2p emission lie well below the experimental data. We identify the presence of unresolved shake-up satellites in the experiment as a potential source of error in the determination of streaking time shifts. However, preliminary results indicate that shake-up states only increase the discrepancy between calculation and experiment. Work supported by the NSF under PHY-1068140, PHY-1212450, and the XSEDE allocation PHY-090031.

  7. Synthetic streak images (x-t diagrams) from high-speed digital video records

    NASA Astrophysics Data System (ADS)

    Settles, Gary

    2013-11-01

    Modern digital video cameras have entirely replaced the older photographic drum and rotating-mirror cameras for recording high-speed physics phenomena. They are superior in almost every regard except, at speeds approaching one million frames/s, sensor segmentation results in severely reduced frame size, especially height. However, if the principal direction of subject motion is arranged to be along the frame length, a simple Matlab code can extract a row of pixels from each frame and stack them to produce a pseudo-streak image or x-t diagram. Such a 2-D image can convey the essence of the large volume of information contained in a high-speed video sequence, and can be the basis for the extraction of quantitative velocity data. Examples include streak shadowgrams of explosions and gunshots, streak schlieren images of supersonic cavity-flow oscillations, and direct streak images of shock-wave motion in polyurea samples struck by gas-gun projectiles, from which the shock Hugoniot curve of the polymer is measured. This approach is especially useful, since commercial streak cameras remain very expensive and rooted in 20th-century technology.

  8. Ultrastructure of internal jugular vein defective valves

    PubMed Central

    Tisato, V; Menegatti, E; Mascoli, F; Gianesini, S; Salvi, F; Secchiero, P

    2015-01-01

    Objectives To study the ultrastructure of intraluminal defects found in the internal jugular vein by using a scanning electron microscopy. Methods Using a scanning electron microscopy, intraluminal septa and/or defective valves blocking the flow in the distal internal jugular vein of seven patients were studied together with the adjacent wall and compared with control specimen. Results The internal jugular veins wall showed a significant derangement of the endothelial layer as compared to controls. Surprisingly, no endothelial cells were found in the defective cusps, and the surface of the structure is covered by a fibro-reticular lamina. Conclusions Although the lack of endothelial cells in the internal jugular vein intraluminal obstacles is a further abnormality found in course of chronic cerebrospinal venous insufficiency, our investigation cannot clarify whether this finding is primary or caused by progressive loss of endothelium in relation to altered haemodynamic forces and/or to a past post-thrombotic/inflammatory remodelling. PMID:24972760

  9. Portal vein thrombosis in liver transplantation.

    PubMed

    Charco, R; Fuster, J; Fondevila, C; Ferrer, J; Mans, E; Garca-Valdecasas, J C

    2005-11-01

    In the initial experience of liver transplantation, complete thrombosis and portal vein occlusion were considered to be absolute contraindications for liver transplantation. The incidence of portal thrombosis in patients being prepared for transplantation varies between 5% and 15% according to published series. There are 2 surgical techniques to solve absent or low portal vein flow due to thrombosis. The most widely used technique is thrombectomy and the second technique is insertion of a shunt with a venous graft in the permeable portion of the superior mesenteric vein or in a vein in the splanchnic territory. Portal thrombosis recurrence rates vary among series, ranging from 0% to 25% or even 30%, depending on its extension and severity and also on time the transplantation was performed. Although overall survival is somewhat lower, there are no significant differences in most of the series when patients with portal thrombosis who underwent transplantation are compared with those without. PMID:16386579

  10. Subclavian vein catheterisation for parenteral nutrition.

    PubMed Central

    Fletcher, J. P.; Little, J. M.

    1988-01-01

    Two hundred and twenty-six central venous catheters were placed in 195 consecutive patients requiring central venous catheterisation for total parenteral nutrition (TPN). Of these 226 catheters, 198 were placed percutaneously into the subclavian vein by the infraclavicular route. In 99 consecutive subclavian catheter insertions, a 12G needle with introducing sheath was used to puncture the vein (Group 1). The Seldinger method of catheterisation was used in another 99 consecutive subclavian catheter insertions (Group 2), the vein being punctured with a 19G needle. Pneumothorax occurred on three occasions (3.0%) in Group 1 but did not occur in Group 2. However, there were two episodes of pleural extravasation in Group 2 (2.0%) which may have been due to guide wire perforation of a central vein; this complication did not occur in Group 1. Although the Seldinger technique of insertion should reduce the incidence of pneumothorax, care should be taken in passage of the guide wire. PMID:3136691

  11. Abdominal collateral vein as an unconventional vascular access for hemodialysis in patient with central vein occlusion.

    PubMed

    Str?ecki, Pawe?; Flisi?ski, Mariusz; Serafin, Zbigniew; Wiechecka-Korenkiewicz, Joanna; Manitius, Jacek

    2014-01-01

    A 65-year-old female patient with chronic kidney disease stage 5 and a history of spleen neoplasm with dissemination within peritoneum is presented. During 5years of hemodialysis therapy, bilateral occlusion of brachiocephalic and iliac vein developed as a consequence of vein catheterization. An attempt to cannulate inferior vena cava was unsuccessful. A cannulation of dilated collateral abdominal veins with dialysis needles allowed to perform several hemodialysis sessions in the patient. PMID:24796505

  12. Variant anatomy of internal jugular vein branching

    PubMed Central

    Deepak, Chris A.; Sarvadnya, Jagadish J.; Sabitha, K. S.

    2015-01-01

    The knowledge of both normal and abnormal anatomy of the veins of the neck is important for clinicians performing catheterization and surgeons operating in the region of the neck. The presence of such anomalous communications may also be important for radiologists performing angiographic and sonographic studies. This study presents three cases of variant anatomy in posterior branching and abnormal branching of internal jugular vein found during our routine neck dissection.

  13. Primary leiomyosarcoma of the innominate vein.

    PubMed

    Illuminati, Giulio; Miraldi, Fabio; Mazzesi, Giuseppe; D'urso, Antonio; Ceccanei, Gianluca; Bezzi, Marcello

    2007-01-01

    Primary venous leiomyosarcoma is rare. We report the case of a primary leiomyosarcoma of the left innominate vein, with neoplastic thrombus extending into the left jugular and subclavian veins. The tumor was curatively resected en bloc with anterior mediastinal and laterocervical lymphatics, through a median sternotomy prolonged into left cervicotomy. Primary venous sarcomas may be associated with prolonged survival in individual cases, with curative resection recommended as the standard treatment, in the absence of distant spread. PMID:17349340

  14. Subclavian vein thrombosis: A continuing challenge

    SciTech Connect

    Hill, S.L.; Berry, R.E. )

    1990-07-01

    Subclavian vein thrombosis is a relatively uncommon but potentially morbid disease entity. To determine the frequency, cause, and best mode of treatment of this problem, we performed a chart review of all patients with a diagnosis of subclavian vein thrombosis at two major metropolitan hospitals during a 6-year period. A total of 40 patients were identified with subclavian vein thrombosis, which represented 3.5% of all venous thromboses detected during the 6-year period. No side or sex predilection was noted and the majority of patients were outpatients. The cause was fairly evenly divided among intravenous catheters (32%), anatomic abnormalities (45%), and carcinoma with postoperative radiation (22.5%). Despite the increasing use of the subclavian veins for pacemaker leads, hyperalimentation, and permanent intravenous access for chemotherapy, there has not been an increase in diagnosed subclavian vein thrombosis. Anatomic abnormalities with compression of the vein respond well to either heparinization or lytic therapy but require surgery if the venous abnormality persists. Treatment consisted of lytic therapy in 20%, heparinization in 55%, and elevation with removal of the central line in 25% of patients. All patients responded well to treatment, with a decrease in swelling and symptoms; no patient progressed to venous gangrene and only one (2.5%) had a documented pulmonary embolus. Medical treatment provides excellent long-term benefit in most cases unless complicated by an anatomic abnormality.

  15. Veins Improve Fracture Toughness of Insect Wings

    PubMed Central

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect’s flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material’s resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m). However, the cross veins increase the wing’s toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm). This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically ‘optimal’ solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial ‘venous’ wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species. PMID:22927966

  16. PROSPECTIVE BIOLOGICAL CONTROL AGENTS FOR YELLOW STARTHISTLE.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow starthistle is an important alien weed that has invaded 20 million acres in the western U.S. Yellow starthistle is spiny plant that interferes with grazing livestock and outdoors recreation, it is fatally poisonous to horses, and it outcompetes desirable vegetation. Previously released agen...

  17. Scattering Removal for Finger-Vein Image Restoration

    PubMed Central

    Yang, Jinfeng; Zhang, Ben; Shi, Yihua

    2012-01-01

    Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of finger-vein image degradation, a biological optical model (BOM) specific to finger-vein imaging is proposed according to the principle of light propagation in biological tissues. Based on BOM, the light scattering component is sensibly estimated and properly removed for finger-vein image restoration. Finally, experimental results demonstrate that the proposed method is powerful in enhancing the finger-vein image contrast and in improving the finger-vein image matching accuracy. PMID:22737028

  18. Unsteady hot streak simulation through a 1-1/2 stage turbine engine

    NASA Astrophysics Data System (ADS)

    Takahashi, R. K.; Ni, R. H.

    1991-06-01

    The temperature redistribution process in a 1-1/2 stage turbine (consisting of a first stator, first rotor, and second stator) was analyzed using an unsteady 3D Euler flow solver. The study concentrated on tracking a hot streak from the inlet of the first stator to the exit of the second stator. The redistribution of the hot streak in the second stator passage was very different from that in the rotor passage, with no signs of temperature segregation in the second stator passage, and with rotor-generated vortices which persist through the second stator passage and partake in redistributing the remains of the hot streak. The unsteady code predicts different time-averaged temperatures and secondary flow in the second stator passage than in the steady multistage code, although the steady code may be sufficient for predicting time-averaged pressure loadings on both rotor and second stator airfoils, and time-averaged secondary flow vortices in the rotor passage.

  19. Cassava brown streak disease: a threat to food security in Africa.

    PubMed

    Patil, Basavaprabhu L; Legg, James P; Kanju, Edward; Fauquet, Claude M

    2015-05-01

    Cassava brown streak disease (CBSD) has emerged as the most important viral disease of cassava (Manihot esculenta) in Africa and is a major threat to food security. CBSD is caused by two distinct species of ipomoviruses, Cassava brown streak virus and Ugandan cassava brown streak virus, belonging to the family Potyviridae. Previously, CBSD was reported only from the coastal lowlands of East Africa, but recently it has begun to spread as an epidemic throughout the Great Lakes region of East and Central Africa. This new spread represents a major threat to the cassava-growing regions of West Africa. CBSD-resistant cassava cultivars are being developed through breeding, and transgenic RNA interference-derived field resistance to CBSD has also been demonstrated. This review aims to provide a summary of the most important studies on the aetiology, epidemiology and control of CBSD and to highlight key research areas that need prioritization. PMID:26015320

  20. Fast phosphor picosecond streak tube for ultrafast laser diagnostics in repetitive mode

    NASA Astrophysics Data System (ADS)

    Ageeva, N. V.; Gornostaev, P. B.; Ivanova, S. R.; Kulechenkova, T. P.; Levina, G. P.; Lozovoi, V. I.; Makushina, V. A.; Schelev, M. Ya; Shashkov, E. V.; Scaballanovich, T. A.; Smirnov, A. V.; Vereschagin, A. K.; Vereschagin, K. A.; Vorobiev, N. S.

    2015-08-01

    The well-established PIF-01/S1/P43 picosecond streak tube, designed 30?years ago and still manufactured at the A.M. Prokhorov General Physics Institute, was modified by replacing its traditional P43 phosphor screen with a P47 one having approximately three orders of magnitude shorter decay time. The experimental measurements of this decay time were provided by PIF-01/S1/P47 image tube photocathode irradiation either with a single or a train of 8?ps laser pulses separated by 8?ns from each other at a 1.08??m wavelength. The results of our preliminary measurements of P47-BH phosphor (manufactured by Phosphor Technology Ltd) indicate the possibility of employing the PIF-01/S1/P47 streak tube for synchrotron diagnostics at a units megahertz repetition rate without the negative influence of ghost images from the previous streak records.

  1. Development of streak cameras for time-resolved experiments at the advanced laser light source laboratory

    NASA Astrophysics Data System (ADS)

    Martel, C.; Fourmaux, S.; Ct, C. Y.; Magnan, S.; Lecherbourg, L.; Kieffer, J. C.

    2007-01-01

    The Advanced Laser light Source (ALLS) infrastructure is a new state-of-the-art multi-beams femtosecond laser facility currently in operation at INRS near Montreal, Canada. Multi-beams experiments and pump-probe geometry lead to the need of synchronization instrumentation tools. The use of a wide range of energy radiation from hard x-ray up to infrared light on the ultrafast time scale requires the development of ultrafast detector diagnostics tools to study the emission spectrum of these sources. To fulfill these requirements, new streak cameras have been developed for ALLS facility. The SV streak camera is a simple and compact multi-purpose instrument that will be used for beams synchronization with picosecond time resolution and good spatial resolution. The FXR streak camera is dedicated to x-ray spectroscopy with sub-picosecond time resolution combined with a very high spatial resolution.

  2. Impact of laser phase and amplitude noises on streak camera temporal resolution

    NASA Astrophysics Data System (ADS)

    Wlotzko, V.; Uhring, W.; Summ, P.

    2015-09-01

    Streak cameras are now reaching sub-picosecond temporal resolution. In cumulative acquisition mode, this resolution does not entirely rely on the electronic or the vacuum tube performances but also on the light source characteristics. The light source, usually an actively mode-locked laser, is affected by phase and amplitude noises. In this paper, the theoretical effects of such noises on the synchronization of the streak system are studied in synchroscan and triggered modes. More precisely, the contribution of band-pass filters, delays, and time walk is ascertained. Methods to compute the resulting synchronization jitter are depicted. The results are verified by measurement with a streak camera combined with a Ti:Al2O3 solid state laser oscillator and also a fiber oscillator.

  3. Absolute calibration method for fast-streaked, fiber optic light collection, spectroscopy systems.

    SciTech Connect

    Johnston, Mark D.; Frogget, Brent; Oliver, Bryan Velten; Maron, Yitzhak; Droemer, Darryl W.; Crain, Marlon D.

    2010-04-01

    This report outlines a convenient method to calibrate fast (<1ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such a system is used to collect spectral data on plasmas generated in the A-K gap of electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA). On RITS, light is collected through a small diameter (200 micron) optical fiber and recorded on a fast streak camera at the output of 1 meter Czerny-Turner monochromator (F/7 optics). To calibrate such a system, it is necessary to efficiently couple light from a spectral lamp into a 200 micron diameter fiber, split it into its spectral components, with 10 Angstroms or less resolution, and record it on a streak camera with 1ns or less temporal resolution.

  4. Performances of a solid streak camera based on conventional CCD with nanosecond time resolution

    NASA Astrophysics Data System (ADS)

    Wang, Bo; Bai, Yonglin; Zhu, Bingli; Gou, Yongsheng; Xu, Peng; Bai, XiaoHong; Liu, Baiyu; Qin, Junjun

    2015-02-01

    Imaging systems with high temporal resolution are needed to study rapid physical phenomena ranging from shock waves, including extracorporeal shock waves used for surgery, to diagnostics of laser fusion and fuel injection in internal combustion engines. However, conventional streak cameras use a vacuum tube making thus fragile, cumbersome and expensive. Here we report an CMOS streak camera project consists in reproducing completely this streak camera functionality with a single CMOS chip. By changing the mode of charge transfer of CMOS image sensor, fast photoelectric diagnostics of single point with linear CMOS and high-speed line scanning with array CMOS sensor can be achieved respectively. A fast photoelectric diagnostics system has been designed and fabricated to investigate the feasibility of this method. Finally, the dynamic operation of the sensors is exposed. Measurements show a sample time of 500 ps and a time resolution better than 2 ns.

  5. Impact of laser phase and amplitude noises on streak camera temporal resolution.

    PubMed

    Wlotzko, V; Uhring, W; Summ, P

    2015-09-01

    Streak cameras are now reaching sub-picosecond temporal resolution. In cumulative acquisition mode, this resolution does not entirely rely on the electronic or the vacuum tube performances but also on the light source characteristics. The light source, usually an actively mode-locked laser, is affected by phase and amplitude noises. In this paper, the theoretical effects of such noises on the synchronization of the streak system are studied in synchroscan and triggered modes. More precisely, the contribution of band-pass filters, delays, and time walk is ascertained. Methods to compute the resulting synchronization jitter are depicted. The results are verified by measurement with a streak camera combined with a Ti:Al2O3 solid state laser oscillator and also a fiber oscillator. PMID:26429463

  6. Oily streaks and focal conic domains in L? lyotropic liquid crystals

    NASA Astrophysics Data System (ADS)

    Boltenhagen, P.; Lavrentovich, O.; Kleman, M.

    1991-10-01

    Observations with the polarizing microscope of defects in the lyotropic L_?(SmA) phase of the quasi-ternary system cetylpiridinium chloride/hexanol/brine give evidence that oily streaks are chains of focal conic domains. The chains are stable in the vicinity of the L_?-L_3 phase transition. Such a model of oily streaks was suggested long ago by G. Friedel but its existence was not confirmed unquestionably. We discuss the geometrical, topological and energetic properties of these structures and show that their stability depends on material constants, in particular, the saddle-splay rigidity bar{K}, whose value can be estimated from the parameters of the oily streaks.

  7. What do Seismicity Streaks and Holes Reveal About the Distribution of Seismic and Aseismic Slip?

    NASA Astrophysics Data System (ADS)

    Rubinstein, J. L.; Beroza, G. C.

    2004-12-01

    Many studies have shown that faults have "holes," i.e., regions of an otherwise active fault that are devoid of microseismicity, both in the aftershock sequences of large earthquakes (e.g., Mendoza and Hartzell, 1988) and during the interseismic interval (e.g., Oppenheimer et al., 1990). Seismicity holes also appear between more recently discovered "streaks" of seismicity on the Calaveras, Hayward, and San Andreas faults in California. Ellsworth et al. (2000) have made a convincing case that two streaks on the San Andreas fault near Parkfield delimit a stuck patch that has been partially ruptured by several magnitude 4+ events in the early 1990's. We examine these same features using precise earthquake relocations for the Calaveras fault. The Calaveras fault has a number of streaks and holes in its seismicity distribution and with the geometry of locked vs. slipping regions more difficult to discern than it is on the San Andreas fault at Parkfield. Our working hypothesis is that the streaks illuminate the transition from creeping to locked portions of the fault. We can test this by examining medium magnitude (M Y 3.5) earthquakes, which we expect to rupture inward from the streaks into areas devoid of microearthquakes, i.e. areas that were previously locked. Double difference relocations show medium sized earthquakes within these streaks, but clipping makes it difficult to determine earthquake locations as accurately for these events. To overcome this problem, we use a first-break master-event cross correlation method to improve hypocentral locations of these larger earthquakes that represent where these moderate magnitude events initiate. Analysis of accelerometer and short-period seismometer records provides finite faulting information, which will allow us to constrain the propagation direction relative to these hypocenters.

  8. System for photometric calibration of optoelectronic imaging devices especially streak cameras

    DOEpatents

    Boni, Robert; Jaanimagi, Paul

    2003-11-04

    A system for the photometric calibration of streak cameras and similar imaging devices provides a precise knowledge of the camera's flat-field response as well as a mapping of the geometric distortions. The system provides the flat-field response, representing the spatial variations in the sensitivity of the recorded output, with a signal-to-noise ratio (SNR) greater than can be achieved in a single submicrosecond streak record. The measurement of the flat-field response is carried out by illuminating the input slit of the streak camera with a signal that is uniform in space and constant in time. This signal is generated by passing a continuous wave source through an optical homogenizer made up of a light pipe or pipes in which the illumination typically makes several bounces before exiting as a spatially uniform source field. The rectangular cross-section of the homogenizer is matched to the usable photocathode area of the streak tube. The flat-field data set is obtained by using a slow streak ramp that may have a period from one millisecond (ms) to ten seconds (s), but may be nominally one second in duration. The system also provides a mapping of the geometric distortions, by spatially and temporarily modulating the output of the homogenizer and obtaining a data set using the slow streak ramps. All data sets are acquired using a CCD camera and stored on a computer, which is used to calculate all relevant corrections to the signal data sets. The signal and flat-field data sets are both corrected for geometric distortions prior to applying the flat-field correction. Absolute photometric calibration is obtained by measuring the output fluence of the homogenizer with a "standard-traceable" meter and relating that to the CCD pixel values for a self-corrected flat-field data set.

  9. Nutcracker Syndrome Complicated by Left Renal Vein Thrombosis

    PubMed Central

    Mallat, Faouzi; Hmida, Wissem; Jaidane, Mehdi; Mama, Nadia; Mosbah, Faouzi

    2013-01-01

    Isolated renal vein thrombosis is a rare entity. We present a patient whose complaint of flank pain led to the diagnosis of a renal vein thrombosis. In this case, abdominal computed tomography angiography was helpful in diagnosing the nutcracker syndrome complicated by the renal vein thrombosis. Anticoagulation was started and three weeks later, CTA showed complete disappearance of the renal vein thrombosis. To treat the Nutcracker syndrome, we proposed left renal vein transposition that the patient consented to. PMID:24349817

  10. Pulmonary Vein Stenosis in a Newborn: A Commonly Overlooked Diagnosis

    PubMed Central

    Bravo-valenzuela, Nathalie Jeanne Magioli; Silva, Guilherme Ricardo Nunes; Varella, Marcela Pinto

    2015-01-01

    The diagnosis of primary pulmonary vein stenosis is often overlooked because its symptoms overlap lung diseases and pulmonary arterial hypertension. Its diagnosis may be difficult because the condition is progressive and associated with other defects. We present a case of pulmonary vein stenosis in a newborn with stenosis of the left-sided common pulmonary vein, diffuse hypoplasia of the superior right pulmonary vein, and atresia of the inferior right pulmonary vein. PMID:26457207

  11. [Pleuritis in yellow nail syndrome].

    PubMed

    Kossakowski, C A; Schmiegelow, P; Müller, K-M

    2012-03-01

    A 76-year-old man presented clinically with coughing and shortness of breath and was diagnosed radiologically to have massive pleural effusion as a combined feature of yellow nail syndrome. A lung biopsy was taken and revealed histologically: chronic non-specific inflammation in the pleuropulmonary border, intrapleural edema with eightfold pleural thickening in comparison to normal, angiogenesis in both the nutritive and functional intrapleural blood vessels, no abnormalities of lymphatic vessels with normal topographical distribution as detected by immunohistochemistry for antibody D2-40, granulomatous chronic foreign body reaction as a consequence of pleural effusion therapy by talcum pleurodesis.The histopathological findings of chronic non-specific pleuritis with angiogenesis and increased permeability of blood vessels led to massive intrapleural edema with pleural effusion. Abnormalities of lymphatic vessels could not be confirmed. Considering the features of this disease, they are probably secondary to chronic r infectious or immunological inflammation or paraneoplastic complications with angiogenesis (in about 19%). PMID:22048329

  12. Experimental therapies for yellow fever

    PubMed Central

    Julander, Justin G.

    2013-01-01

    A number of viruses in the family Flaviviridae are the focus of efforts to develop effective antiviral therapies. Success has been achieved with inhibitors for the treatment of hepatitis C, and there is interest in clinical trials of drugs against dengue fever. Antiviral therapies have also been evaluated in patients with Japanese encephalitis and West Nile encephalitis. However, no treatment has been developed against the prototype flavivirus, yellow fever virus (YFV). Despite the availability of the live, attenuated 17D vaccine, thousands of cases of YF continue to occur each year in Africa and South America, with a significant mortality rate. In addition, a small number of vaccinees develop severe systemic infections with the 17D virus. This paper reviews current efforts to develop antiviral therapies, either directly targeting the virus or blocking detrimental host responses to infection. PMID:23237991

  13. Probing dielectric-response effects with attosecond time-resolved streaked photoelectron spectroscopy of metal surfaces

    SciTech Connect

    Zhang, C.-H.; Thumm, U.

    2011-12-15

    The release of conduction-band electrons from a metal surface by a subfemtosecond extreme ultraviolet (XUV) pulse and their propagation through the solid provoke a dielectric response in the solid that acts back on the photoelectron wave packet. We calculated the (wake) potential associated with this photoelectron self-interaction in terms of bulk and surface plasmon excitations and show that it induces a considerable, XUV-frequency-dependent temporal shift in laser-streaked XUV photoemission spectra, suggesting the observation of the ultrafast solid-state dielectric response in contemporary streaked photoemission experiments.

  14. Accurate and efficient characterization of streak camera using etalon and fitting method with constraints.

    PubMed

    Yang, Dong; Wang, Zhebin; Jiang, Xiaohua; Liu, Yonggang; Peng, Xiaoshi; Zhu, Tuo; Zhang, Huan; Li, Zhichao; Li, Sanwei; Ding, Yongkun

    2011-11-01

    Streak camera is widely used in continuous time diagnostics in fast physical process. To produce accurate result, it requires delicate calibration and a reliable analysis method. High quality sweep-rate data with uncertainty smaller than 0.5% are obtained over the full record area by a constrained fitting method of peak position measurement, with a short pulse laser and an etalon as the fiducial source. The temporal response is linearized by this full-screen sweep-rate data, which eliminates errors in measurement due to nonlinearity and space-distortion inherent in streak camera. PMID:22128970

  15. Linear stability of optimal streaks in the log-layer of turbulent channel flows

    NASA Astrophysics Data System (ADS)

    Alizard, Frdric

    2015-10-01

    The importance of secondary instability of streaks for the generation of vortical structures attached to the wall in the logarithmic region of turbulent channels is studied. The streaks and their linear instability are computed by solving equations associated with the organized motion that include an eddy-viscosity modeling the effect of incoherent fluctuations. Three friction Reynolds numbers, Re? = 2000, 3000, and 5000, are investigated. For all flow cases, optimal streamwise vortices (i.e., having the highest potential for linear transient energy amplification) are used as initial conditions. Due to the lift-up mechanism, these optimal perturbations lead to the nonlinear growth of streaks. Based on a Floquet theory along the spanwise direction, we observe the onset of streak secondary instability for a wide range of spanwise wavelengths when the streak amplitude exceeds a critical value. Under neutral conditions, it is shown that streak instability modes have their energy mainly concentrated in the overlap layer and propagate with a phase velocity equal to the mean streamwise velocity of the log-layer. These neutral log-layer modes exhibit a sinuous pattern and have characteristic sizes that are proportional to the wall distance in both streamwise and spanwise directions, in agreement with the Townsend's attached eddy hypothesis (A. Townsend, the structure of turbulent shear flow, Cambridge university press, 1976 2nd edition). In particular, for a distance from the wall varying from y+ ? 100 (in wall units) to y ? 0.3h, where h is half the height of the channel, the neutral log-layer modes are self-similar with a spanwise width of ?z ? y/0.3 and a streamwise length of ?x ? 3?z, independently of the Reynolds number. Based on this observation, it is suggested that compact vortical structures attached to the wall can be ascribed to streak secondary instabilities. In addition, spatial distributions of fluctuating vorticity components show that the onset of secondary instability is associated with the roll-up of the shear layer at the edge of the low-speed streak, similarly to a three-dimensional mixing layer.

  16. A grazing incidence x-ray streak camera for ultrafast, single-shot measurements

    SciTech Connect

    Feng, Jun; Engelhorn, K.; Cho, B.I.; Lee, H.J.; Greaves, M.; Weber, C.P.; Falcone, R.W.; Padmore, H. A.; Heimann, P.A.

    2010-02-18

    An ultrafast x-ray streak camera has been realized using a grazing incidence reflection photocathode. X-rays are incident on a gold photocathode at a grazing angle of 20 degree and photoemitted electrons are focused by a large aperture magnetic solenoid lens. The streak camera has high quantum efficiency, 600fs temporal resolution, and 6mm imaging length in the spectral direction. Its single shot capability eliminates temporal smearing due to sweep jitter, and allows recording of the ultrafast dynamics of samples that undergo non-reversible changes.

  17. 78 FR 24199 - Streak Products, Inc. v. UTi, United States, Inc.; Notice of Filing of Complaint and Assignment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... Streak Products, Inc. v. UTi, United States, Inc.; Notice of Filing of Complaint and Assignment Notice is... Products, Inc. (``Streak''), hereinafter ``Complainant,'' against UTi, United States, Inc. (``UTi...). Complainant also alleges that ``UTi engaged in an unfair or unjustly discriminatory practice in violation...

  18. Deep vein thrombosis: a clinical review

    PubMed Central

    Kesieme, Emeka; Kesieme, Chinenye; Jebbin, Nze; Irekpita, Eshiobo; Dongo, Andrew

    2011-01-01

    Background: Deep vein thrombosis (DVT) is the formation of blood clots (thrombi) in the deep veins. It commonly affects the deep leg veins (such as the calf veins, femoral vein, or popliteal vein) or the deep veins of the pelvis. It is a potentially dangerous condition that can lead to preventable morbidity and mortality. Aim: To present an update on the causes and management of DVT. Methods: A review of publications obtained from Medline search, medical libraries, and Google. Results: DVT affects 0.1% of persons per year. It is predominantly a disease of the elderly and has a slight male preponderance. The approach to making a diagnosis currently involves an algorithm combining pretest probability, D-dimer testing, and compression ultrasonography. This will guide further investigations if necessary. Prophylaxis is both mechanical and pharmacological. The goals of treatment are to prevent extension of thrombi, pulmonary embolism, recurrence of thrombi, and the development of complications such as pulmonary hypertension and post-thrombotic syndrome. Conclusion: DVT is a potentially dangerous condition with a myriad of risk factors. Prophylaxis is very important and can be mechanical and pharmacological. The mainstay of treatment is anticoagulant therapy. Low-molecular-weight heparin, unfractionated heparin, and vitamin K antagonists have been the treatment of choice. Currently anticoagulants specifically targeting components of the common pathway have been recommended for prophylaxis. These include fondaparinux, a selective indirect factor Xa inhibitor and the new oral selective direct thrombin inhibitors (dabigatran) and selective factor Xa inhibitors (rivaroxaban and apixaban). Others are currently undergoing trials. Thrombolytics and vena caval filters are very rarely indicated in special circumstances. PMID:22287864

  19. KB-PJX-A streaked imager based on a versatile x-ray microscope coupled to a high-current streak tube (invited)

    NASA Astrophysics Data System (ADS)

    Gotchev, O. V.; Jaanimagi, P. A.; Knauer, J. P.; Marshall, F. J.; Meyerhofer, , D. D.

    2004-10-01

    A re-entrant, highly adaptable, x-ray streaked imager has been developed for OMEGA to increase the sensitivity and spatial resolution in hydrodynamic-stability experiments. It is based on a four-mirror Kirkpatrick-Baez (KB) microscope, coupled to a high-current streak tube. The unique mechanical assembly of the KB optic allows a choice between single- or multi-image modes and one- or two-dimensional imaging. Currently, the optic uses an Ir coating at a grazing angle of 2.1. The incidence angle has been optimized to maximize throughput in the chosen energy band, centered at 1.5 keV with a full width at half maximum of about 0.4 keV. A calculated resolution of better than 5 ?m over the central 200 ?m of the field of view was verified in inertial confinement fusion experiments. New multilayer mirror elements for high-energy or multiband imaging, take advantage of the flexible mechanical design. Some important features of the PJX streak tube are described.

  20. KB-PJX--A streaked imager based on a versatile x-ray microscope coupled to a high-current streak tube (invited)

    SciTech Connect

    Gotchev, O.V.; Jaanimagi, P.A.; Knauer, J.P.; Marshall, F.J.; Meyerhofer, D.D.

    2004-10-01

    A re-entrant, highly adaptable, x-ray streaked imager has been developed for OMEGA to increase the sensitivity and spatial resolution in hydrodynamic-stability experiments. It is based on a four-mirror Kirkpatrick-Baez (KB) microscope, coupled to a high-current streak tube. The unique mechanical assembly of the KB optic allows a choice between single- or multi-image modes and one- or two-dimensional imaging. Currently, the optic uses an Ir coating at a grazing angle of 2.1 deg. The incidence angle has been optimized to maximize throughput in the chosen energy band, centered at 1.5 keV with a full width at half maximum of about 0.4 keV. A calculated resolution of better than 5 {mu}m over the central 200 {mu}m of the field of view was verified in inertial confinement fusion experiments. New multilayer mirror elements for high-energy or multiband imaging, take advantage of the flexible mechanical design. Some important features of the PJX streak tube are described.

  1. An anomalous left external jugular vein draining into right subclavian vein.

    PubMed

    Vadgaonkar, Rajanigandha; Rai, Rajalakshmi; Ranade, Anu V; Pai, Mangala M; Prabhu, Latha V; Ashwin, K; Jiji, P J

    2008-01-01

    Knowledge of the varying drainage patterns of superficial veins of head & neck, in particular, jugular veins are not only important for anatomists but also for the surgeons operating at this level and to clinicians in general. The variations are important also for interventional radiologists, who perform trans-jugular procedures, such as port implantations and trans-jugular intra-hepatic porto-systemic shunts or selective venous samplings. Results of recent studies report that the superficial veins, especially the external jugular vein, have been increasingly utilized for cannulation to conduct diagnostic and therapeutic procedures. We report a very unusual left-sided presentation of external jugular vein in an embalmed male cadaver. Embryological evaluations of the anomaly was done & compared with available literature, which showed that the observed variation is rare (Fig. 1, Ref. 12). PMID:19166133

  2. Veining Failure and Hydraulic Fracturing in Shales

    NASA Astrophysics Data System (ADS)

    Mighani, S.; Sondergeld, C. H.; Rai, C. S.

    2014-12-01

    During the hydraulic fracturing, the pressurized fluid creates new fractures and reactivates existing natural fractures forming a highly conductive Stimulated Reservoir Volume (SRV) around the borehole. We extend the previous work on Lyons sandstone and pyrophyllite to anisotropic shale from the Wolfcamp formation. We divide the rock anisotropy into two groups: a) conventional and b) unconventional (shaly) anisotropy. X-ray Computed Tomography (CT), compressional velocity anisotropy, and SEM analysis are used to identify three causes of anisotropy: bedding planes, clay lamination, and calcite veins. Calcite vein is a subsequently filled with calcite bonded weakly to the matrix. Velocity anisotropy and visual observations demonstrate the calcite filled veins to be mostly subparallel to the fabric direction. Brazilian tests are carried out to observe the fracture initiation and propagation under tension. High speed photography (frame rate 300,000 frame/sec) was used to capture the failure. Strain gauges and Acoustic Emission (AE) sensors recorded the deformation leading up to and during failure. SEM imaging and surface profilometry were employed to study the post-failure fracture system and failed surface topology. Fracture permeability was measured as a function of effective stress. Brazilian tests on small disks containing a centered single vein revealed the shear strength of the veins. We interpret the strain data and number, frequency, and amplitude of AE events which are correlated well with the observed fracture process zone, surface roughness, and permeability. The unpropped fracture has enhanced permeability by two orders of magnitude. The observed anisotropic tensile failure seems to have a universal trend with a minimum strength occurring at 15o orientation with respect to the loading axis. The veins at 15o orientation with respect to the loading axis were easily activated at 30% of the original failure load. The measured strength of the vein is as low as 6% of the matrix. Surface roughness measurements show the vein to be as rough as the main tensile fracture in the matrix. The observations suggest that fracking through a deviated well reduces the breakdown pressure significantly and can activate a large number of veins with enhanced conductivity without the need for excessive proppant injection.

  3. Optimization of subcutaneous vein contrast enhancement

    NASA Astrophysics Data System (ADS)

    Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

    2000-05-01

    A technique for enhancing the contrast of subcutaneous veins has been demonstrated. This techniques uses a near IR light source and one or more IR sensitive CCD TV cameras to produce a contrast enhanced image of the subcutaneous veins. This video image of the veins is projected back onto the patient's skin using a n LCD video projector. The use of an IR transmitting filter in front of the video cameras prevents any positive feedback from the visible light from the video projector from causing instabilities in the projected image. The demonstration contrast enhancing illuminator has been tested on adults and children, both Caucasian and African-American, and it enhances veins quite well in all cases. The most difficult cases are those where significant deposits of subcutaneous fat are present which make the veins invisible under normal room illumination. Recent attempts to see through fat using different IR wavelength bands and both linearly and circularly polarized light were unsuccessful. The key to seeing through fat turns out to be a very diffuse source of RI light. Results on adult and pediatric subjects are shown with this new IR light source.

  4. The anatomy of the cardiac veins in mice

    PubMed Central

    Ciszek, Bogdan; Skubiszewska, Daria; Ratajska, Anna

    2007-01-01

    Although the cardiac coronary system in mice has been the studied in detail by many research laboratories, knowledge of the cardiac veins remains poor. This is because of the difficulty in marking the venous system with a technique that would allow visualization of these large vessels with thin walls. Here we present the visualization of the coronary venous system by perfusion of latex dye through the right caudal vein. Latex injected intravenously does not penetrate into the capillary system. Murine cardiac veins consist of several principal branches (with large diameters), the distal parts of which are located in the subepicardium. We have described the major branches of the left atrial veins, the vein of the left ventricle, the caudal veins, the vein of the right ventricle and the conal veins forming the conal venous circle or the prepulmonary conal venous arch running around the conus of the right ventricle. The venous system of the heart drains the blood to the coronary sinus (the left cranial caval vein) to the right atrium or to the right cranial caval vein. Systemic veins such as the left cranial caval, the right cranial caval and the caudal vein open to the right atrium. Knowledge of cardiac vein location may help to elucidate abnormal vein patterns in certain genetic malformations. PMID:17553104

  5. Laser ablation of cutaneous leg veins.

    PubMed

    Almeida, Jose I; Raines, Jeffrey K

    2008-12-01

    Patients presenting with lower-extremity telangiectasias, commonly known as spider veins, are a frequent presentation for vascular surgeons. The use of lasers in the treatment of lower-extremity spider veins has gained increased popularity during the past 5 years. This technology, driven by consumer demand, has been effective in treating vessels that are refractory to sclerotherapy treatment, vessels that arise from telangiectatic matting, and in patients who experience a phobia to needles. One laser wavelength per machine limits what the practitioner can do. That is, each type of vein responds best to a specific wavelength. Light skin is more forgiving to complications than dark skin. The devices are a complement to good sclerotherapy, not a substitute. PMID:19028771

  6. Endovascular interventions for central vein stenosis

    PubMed Central

    Agarwal, Anil K.

    2015-01-01

    Central vein stenosis is common because of the placement of venous access and cardiac intravascular devices and compromises vascular access for dialysis. Endovascular intervention with angioplasty and/or stent placement is the preferred approach, but the results are suboptimal and limited. Primary patency after angioplasty alone is poor, but secondary patency can be maintained with repeated angioplasty. Stent placement is recommended for quick recurrence or elastic recoil of stenosis. Primary patency of stents is also poor, though covered stents have recently shown better patency than bare metal stents. Secondary patency requires repeated intervention. Recanalization of occluded central veins is tedious and not always successful. Placement of hybrid graft-catheter with a combined endovascular surgical approach can maintain patency in many cases. In the presence of debilitating symptoms, palliative approach with endovascular banding or occlusion of the access may be necessary. Prevention of central vein stenosis is the most desirable strategy. PMID:26779426

  7. Pulmonary Vein Stenosis Mimicking Nonspecific Interstitial Pneumonia

    PubMed Central

    Linga, Karthika R.; Khoor, Andras; Phelan, Jonathan A.; Mira-Avendano, Isabel

    2015-01-01

    Pulmonary vein stenosis (PVS) is a known complication after catheter ablation of arrhythmias. Surprisingly, little information is available on its manifestations in the lung. We describe the case of a 39-year-old woman who presented from an outside hospital with worsening shortness of breath after catheter ablation of pulmonary veins for atrial fibrillation. After an initial diagnosis of pneumonia and its nonimprovement with antibiotics, a surgical lung biopsy was done and interpreted as nonspecific interstitial pneumonia (NSIP) with vascular changes consistent with pulmonary arterial hypertension. Later, she was admitted to our institution where a transthoracic echocardiogram (TTE) and subsequent computed tomography (CT) angiogram of the heart showed severe stenosis of all four pulmonary veins. The previous lung biopsy was rereviewed and reinterpreted as severe parenchymal congestion mimicking NSIP. Our case demonstrates that PVS is an underrecognized complication of catheter ablation, and increased awareness among both clinicians and pathologists is necessary to avoid misdiagnosis. PMID:26779359

  8. Evaluation of banana hybrids for tolerance to black leaf streak (Mycosphaerella fijiensis Morelet) in Puerto Rico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Puerto Rico, bananas (including plantains) are important agricultural commodities; their combined production totaled 133,500 tons in 2008. Black leaf streak (BLS) and Sigatoka leaf spot diseases, caused by Mycosphaerella fijiensis and M. musicola, respectively, are responsible for significant los...

  9. Multiplex Real Time PCR For Detection of Wheat Streak Mosaic Virus and Triticum Mosaic Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TRIMV) are widespread throughout the southwestern Great Plains states. Using conventional diagnostics such as Enzyme-Linked Immunosorbent Assays (ELISA), these two viruses are commonly found together in infected wheat samples. Methods for m...

  10. Multiple roles of Wheat streak mosaic virus coat protein in virus biology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is an economically important member of the Potyviridae family impacting wheat production in the Great Plains region. The role of WSMV coat protein (CP) in virus biology was examined by introducing a series of point or deletion mutations into the CP cistron, and it wa...

  11. MAIZE NECROTIC STREAK VIRUS IS MOST CLOSELY RELATED TO MEMBERS OF THE GENUS TOMBUSVIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Initial reports indicated that Maize necrotic streak virus (MNeSV) is most closely related to viruses in the family Tombusviridae. The two 5' most open reading frames (ORFs) are most simlar to the corresponding tombusvirus proteins, while the 27.4 kDa coat protein (CP) is more closely related to th...

  12. Efficient inoculation of rice black-streaked dwarf virus to maize using Laodelphax striatellus Fallen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize rough dwarf disease (MRDD) caused by Rice black-streaked dwarf virus (RBSDV) is the most important viral disease of maize in China. Although deploying disease resistant hybrids would be the most effective way to control the disease, development of resistant hybrids has been limited by virus t...

  13. Nuclear import of Maize fine streak virus proteins in Drosophila S2 cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize fine streak virus (MFSV) is a member of the genus Nucleorhabdovirus, family Rhabdoviridae and is transmitted by the leafhopper Graminella nigrifons. The virus replicates in both its plant host and in its insect vector. Nucleorhabdoviruses replicate in the nucleus and assemble at the inner nu...

  14. ESTIMATING OF EFFECTIVE POPULATION SIZES OF LABORATORY AND FIELD SAMPLES OF WHEAT STREAK MOSAIC VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously have used two different approaches, each essentially measuring the rate of genetic drift, to arrive at estimates effective population size (Ne) of wheat streak mosaic virus (WSMV) that are remarkably low. Fixation rates in plants infected with two strains of WSMV yielded Ne = 4 for sy...

  15. Pedicle streaking: A novel and simple aid in pedicle positioning in free tissue transfer

    PubMed Central

    Aggarwal, Aditya; Singh, Hardeep; Mahendru, Sanjay; Brajesh, Vimalendu; Singh, Sukhdeep; Khare, Ashish; Kothari, Umang; Khazanchi, Rakesh Kumar

    2015-01-01

    Introduction: The pedicle positioning in free tissue transfer is critical to its success. Long thin pedicles are especially prone to this complication where even a slight twist in the perforator can result in flap loss. Pedicles passing through the long tunnels are similarly at risk. Streaking the pedicle with methylene blue is a simple and safe method which increases the safety of free tissue transfer. Materials and Methods: Once the flap is islanded on the pedicle and the vascularity of the flap is confirmed, the pedicle is streaked with methylene blue dye at a distance of 6-7 mm. The streaking starts from the origin of the vessels and continued distally on to the under surface of flap to mark the complete course of the pedicle in alignment. The presence of streaking in some parts and not in rest indicates twist in the pedicle. Observation and Results: Four hundred and sixty five free flaps have been done at our centre in the last 5 years. The overall success rate of free flaps is 95.3% (22 free flap failures). There has not been a single case of pedicle twist leading to flap congestion and failure. Conclusion: This simple and novel method is very reliable for pedicle positioning avoiding any twist necessary for successful free tissue transfer.

  16. Simultaneous velocity interferometry and electronic streak photography of laser-launched plates

    SciTech Connect

    Paisley, D.L.; Stahl, D.B.; Garcia, I.A.

    1991-01-01

    Laser-launched, miniature, pseudo-one-dimensional flyer plates are evaluated by three distinct optical techniques that may be incorporated into an optical diagnostic system to give a complete understanding of the plate performance. These techniques are: velocity interferometry, streak photography, and pulsed laser stereo photography. 2 refs., 5 figs.

  17. Plant host range and leafhopper transmission of Maize fine streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize fine streak virus (MFSV), an emerging rhabdovirus species in the genus Nucleorhabdovirus, is persistently transmitted by the black-faced leafhopper, Graminella nigrifrons (Forbes). MFSV was transmitted to maize, wheat, oats, rye, barley, foxtail, annual ryegrass and quackgrass by G. nigrifron...

  18. INFECTIOUS CDNA TRANSCRIPTS OF MAIZE NECROTIC STREAK VIRUS: INFECTIVITY AND TRANSLATIONAL CHARACTERISTICS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The completion of the sequence of Maize necrotic streak virus (MNeSV) indicated a genome of 4094 nt. Northern blotting and primer extension mapping identified two sgRNAs, 1607 nt and 781 nt long. Comparison of the MNeSV and Tomato bushy stunt virus genome sequences indicated that tombusvirus regulat...

  19. Economic impact of wheat streak mosaic virus in the Texas High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV), vectored by the wheat curl mite Aceria tosichella Keifer, is a major limiting factor in wheat production in the Texas Panhandle. It is the most frequently encountered virus in the region, affecting both shoot and root biomass, and consequently it can drastically red...

  20. Optical Comb Generation for Streak Camera Calibration for Inertial Confinement Fusion Experiments

    SciTech Connect

    Ronald Justin, Terence Davies, Frans Janson, Bruce Marshall, Perry Bell, Daniel Kalantar, Joseph Kimbrough, Stephen Vernon, Oliver Sweningsen

    2008-09-18

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is coming on-line to support physics experimentation for the U.S. Department of Energy (DOE) programs in Inertial Confinement Fusion (ICF) and Stockpile Stewardship (SS). Optical streak cameras are an integral part of the experimental diagnostics instrumentation at NIF. To accurately reduce streak camera data a highly accurate temporal calibration is required. This article describes a technique for simultaneously generating a precise +/- 2 ps optical marker pulse (fiducial reference) and trains of precisely timed, short-duration optical pulses (so-called comb pulse trains) that are suitable for the timing calibrations. These optical pulse generators are used with the LLNL optical streak cameras. They are small, portable light sources that, in the comb mode, produce a series of temporally short, uniformly spaced optical pulses, using a laser diode source. Comb generators have been produced with pulse-train repetition rates up to 10 GHz at 780 nm, and somewhat lower frequencies at 664 nm. Individual pulses can be as short as 25-ps FWHM. Signal output is via a fiber-optic connector on the front panel of the generator box. The optical signal is transported from comb generator to streak camera through multi-mode, graded-index optical fiber.

  1. Complete genome sequence of an emerging genotype of tobacco streak virus in the U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report the complete genome sequence of an emerging genotype of Tobacco streak virus (TSV) infecting zucchini squash in Florida (TSV_FL13-07), through deep sequencing of sRNAs and validation by Sanger sequencing. TSV_FL13-07 only shares less than 90% sequence identity in three genomic ribonucleic...

  2. INSECT VECTOR COMPETENCE AND GENOME SEQUENCE ANALYSIS OF MAIZE FINE STREAK RHABDOVIRUS (MFSV)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize fine streak virus (MFSV) is a newly discovered member of the genus Nucleorhabdovirus. Insect transmission of rhabdoviruses is highly specific; a given rhabdovirus is transmitted only by one or a few closely related insect species. The goal of this study is to identify and characterize factor...

  3. The new ultra high-speed all-optical coherent streak-camera

    NASA Astrophysics Data System (ADS)

    Arkhipov, R. M.; Arkhipov, M. V.; Egorov, V. S.; Chekhonin, I. A.; Chekhonin, M. A.; Bagayev, S. N.

    2015-11-01

    In the present paper a new type of ultra high-speed all-optical coherent streak-camera was developed. It was shown that a thin resonant film (quantum dots or molecules) could radiate the angular sequence of delayed ultra-short pulses if a transverse spatial periodic distribution of the laser pump field amplitude has a triangle shape.

  4. Picosecond streak camera display of an intermodal coupling matrix at a multimode fiber splice

    NASA Technical Reports Server (NTRS)

    Louradour, F.; Shaklan, Stuart

    1991-01-01

    A technique is developed that permits direct visualization of the coupling matrix for all guided modes of a moderately multimode fiber optic at a splice or mode coupler. The matrix is formed by an array of spots at the output of a picosecond streak camera. The technique also permits unambiguous determination of the phase velocity and group velocity of the modes.

  5. Standard design for National Ignition Facility x-ray streak and framing cameras.

    PubMed

    Kimbrough, J R; Bell, P M; Bradley, D K; Holder, J P; Kalantar, D K; MacPhee, A G; Telford, S

    2010-10-01

    The x-ray streak camera and x-ray framing camera for the National Ignition Facility were redesigned to improve electromagnetic pulse hardening, protect high voltage circuits from pressure transients, and maximize the use of common parts and operational software. Both instruments use the same PC104 based controller, interface, power supply, charge coupled device camera, protective hermetically sealed housing, and mechanical interfaces. Communication is over fiber optics with identical facility hardware for both instruments. Each has three triggers that can be either fiber optic or coax. High voltage protection consists of a vacuum sensor to enable the high voltage and pulsed microchannel plate phosphor voltage. In the streak camera, the high voltage is removed after the sweep. Both rely on the hardened aluminum box and a custom power supply to reduce electromagnetic pulse/electromagnetic interference (EMP/EMI) getting into the electronics. In addition, the streak camera has an EMP/EMI shield enclosing the front of the streak tube. PMID:21034058

  6. Localization of sympathetic postganglionic neurons innervating mesenteric artery and vein in rats.

    PubMed

    Hsieh, N K; Liu, J C; Chen, H I

    2000-04-12

    Physiological and histochemical studies have demonstrated the control and innervation of sympathetic nerves to the artery and vein vessels of splanchnic circulation. In our laboratory, we first used the technique of retrograde transport of horseradish peroxidase to identify the origin of sympathetic neurons innervating the mesenteric vein. In this study, double fluorescence staining technique was used for a simultaneous localization of the sympathetic postganglionic neurons supplying the mesenteric artery and vein in rats. First-order branches of mesenteric artery (A) and vein (V) in the vicinity of ileo-cecal junction were isolated for application of fluorescent dyes (Fast Blue, FB and Diamidino Yellow, DY). The application of FB and DY on A and V was alternated in the next animal to minimize the difference in dye uptake. The animal was allowed to recover for 6-7 days assuring a complete uptake of FB and DY into the cytoplasm and nucleus, respectively. The number of FB, DY and double staining neurons in the prevertebral and paravertebral ganglia were counted under a fluorescent microscope after animal fixation and serial frozen section (30 microm) of the sympathetic ganglia. Our study revealed the following findings: (1) Distribution of the fluorescence-staining neurons in the sympathetic ganglia was as follows: right celiac ganglion (39%), superior mesenteric ganglion (30%), left celiac ganglion (26%), inferior mesenteric ganglion (1%) and paravertebral ganglia (4%). (2) Double staining neurons that dually innervate A and V amounted to 54% of total staining neurons. There were 41% neurons singly innervating A and 5% innervating V. (3) The ratio of neurons supplying the A and V ranged from 1.41 to 1.75 (average 1.61). (4) There was no distinct topographical distribution with respect to the neuron location innervating A and V. The distribution of neurons appeared in a scattering pattern. PMID:10742533

  7. Successful liver allograft inflow reconstruction with the right gastroepiploic vein.

    PubMed

    Pinheiro, Rafael S; Cruz, Ruy J; Nacif, Lucas S; Vane, Matheus F; D'Albuquerque, Luiz Ac

    2016-02-01

    Portal vein thrombosis is a common complication in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusual case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric orthotopic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advantage of avoiding the need of venous jump graft. PMID:26818551

  8. How Vein Sealing Boosts Fracture Opening

    NASA Astrophysics Data System (ADS)

    Nüchter, Jens-Alexander

    2015-04-01

    Veins from from cracks. As such, a stage of brittle failure and fracturing is to be set apart from a stage of opening and sealing. The process of fracture opening requires distortion of the host rocks to create space for the evolving vein. To keep a crack arrested and, at the same time, to widen or stabilize the cavity, the stress intensity factor K_I=(P-S3)(πa) must remain below the fracture toughness K_IC of the host rock, and P-S3 >0 (P and S3 denote pore fluid pressure and absolute minimum principal stress, respectively and 'a' refers to the half-length of the fracture). For purely elastic distortion of the host rocks, maximum aperture W0=K_IC (1-ν^2)/(E(π/8)^1/2))(2a)^1/2 depends on on K_IC, Poisson's ratio ν, and Young's modulus E of the host rocks. Owing to the low values for rock K_IC typically ranging between 0.1 and 1 MPa m^1/2, veins formed by purely elastic distortion of the host rocks are restricted to high aspect ratios 2a/W. In metamorphic rocks, veins with low aspect ratios are common; inelastic deformation and viscous creep in the host rocks must have contributed to final vein shapes. In the present study, I use finite element models to simulate fracture opening and cavity formation supported by viscous creep distributed in the host rock. Simulations are carried out on 2D plate models containing elliptical fractures. The walls of the fractures are coated by thin layers simulating incipient sealing; a residual cavity prevails in the centre of the model veins. Constant displacement is applied to the plate boundaries oriented normal to the cracks. I run a series of models with various viscosity contrasts between the rocks and the sealing. The results of these models indicate the following. (1) Fracture opening is most effective when the viscosity of the sealing ηs exceeds the viscosity of the host rocks ηr (2) The rate of fracture opening increases with increasing values for ηs/ηr . (3) An increase in the thickness of the sealing layer causes an increase in the fracture opening rates. (4) At constant strain rates, the rate of fracture opening increases with increasing strain. These results suggest that vein sealing boosts the rate of fracture opening, and contributes to development of low-aspect ratio veins.

  9. Portal Vein Aneurysm Presenting with Obstructive Jaundice

    PubMed Central

    Lall, Chandana; Verma, Sadhna; Gulati, Rajesh; Bhargava, Puneet

    2012-01-01

    To the best of our knowledge, a portal vein aneurysm presenting with obstructive jaundice has not been reported in the literature. The preferred treatment for these aneurysms is surgical and a shunting procedure should be considered in cases with portal hypertension to preserve portal vein flow when portal hypertension is present or is secondary to the aneurysm itself. In our case, due to patient's advanced age and co-morbidities, an endoscopic biliary stent was placed which led to successful resolution of symptoms of obstructive jaundice. PMID:23029637

  10. Imaging of Postpartum Ovarian Vein Thrombosis

    PubMed Central

    Bilgin, Mehmet; Sevket, Osman; Yildiz, Seyma; Sharifov, Rasul; Kocakoc, Ercan

    2012-01-01

    Postpartum ovarian vein thrombosis (OVT) is a rare but serious complication. Clinical findings of OVT are nonspecific. Postpartum OVT, which is a clinically difficultly diagnosed entity, must be thought of in differential diagnosis in cases of postpartum acute abdomen. OVT can be accurately diagnosed by appropriate noninvasive radiologic modalities to start early therapy with anticoagulants and intravenous antibiotics. In this paper, we review the imaging findings of a case with postpartum ovarian vein thrombosis that had been followed up for 6 months by ultrasonography (US), color Doppler US, computed tomography (CT), and magnetic resonance imaging (MRI). PMID:23133765

  11. Superficial Vein Thrombophlebitis in a Football Athlete.

    PubMed

    Schleich, Kevin T; Smoot, M Kyle

    2016-03-01

    A 22-year-old professional football player presented to a preparticipation physical examination with a 2-week history of left leg discomfort extending from the groin to the knee over the previous 2 weeks. He was found to have superficial vein thrombophlebitis (SVT) of the left great saphenous vein extending from the knee to within approximately 1.6 cm of the saphenofemoral junction. There is paucity in the literature regarding the management of SVT, particularly in actively training athletes. This case addresses the considerations of anticoagulation management for SVT as well as the unique challenge of managing anticoagulation therapy in an athlete that is actively training. PMID:25961158

  12. A Comprehensive Evaluation of Yellow-flowering Magnolias

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A collection of yellow-flowering magnolias were evaluated for flower color, bloom duration and growth rate in USDA Hardiness Zone 6b. All selections were reported to have yellow blooms; however, tepal color in this test ranged from light pink with some yellow coloration to dark yellow. The darkest...

  13. 7 CFR 28.441 - Strict Middling Yellow Stained Color.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Strict Middling Yellow Stained Color. 28.441 Section... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.441 Strict Middling Yellow Stained Color. Strict Middling Yellow Stained Color is color which is deeper...

  14. 7 CFR 28.441 - Strict Middling Yellow Stained Color.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Strict Middling Yellow Stained Color. 28.441 Section... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.441 Strict Middling Yellow Stained Color. Strict Middling Yellow Stained Color is color which is deeper...

  15. 7 CFR 28.442 - Middling Yellow Stained Color.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.442 Middling Yellow Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper...

  16. 7 CFR 28.442 - Middling Yellow Stained Color.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.442 Middling Yellow Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper...

  17. 7 CFR 28.442 - Middling Yellow Stained Color.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.442 Middling Yellow Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper...

  18. 7 CFR 28.442 - Middling Yellow Stained Color.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.442 Middling Yellow Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper...

  19. 7 CFR 28.442 - Middling Yellow Stained Color.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.442 Middling Yellow Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper...

  20. 7 CFR 28.441 - Strict Middling Yellow Stained Color.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Strict Middling Yellow Stained Color. 28.441 Section... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.441 Strict Middling Yellow Stained Color. Strict Middling Yellow Stained Color is color which is deeper...

  1. 7 CFR 28.441 - Strict Middling Yellow Stained Color.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Strict Middling Yellow Stained Color. 28.441 Section... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.441 Strict Middling Yellow Stained Color. Strict Middling Yellow Stained Color is color which is deeper...

  2. 7 CFR 28.441 - Strict Middling Yellow Stained Color.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Middling Yellow Stained Color. 28.441 Section... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Yellow Stained Cotton § 28.441 Strict Middling Yellow Stained Color. Strict Middling Yellow Stained Color is color which is deeper...

  3. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  4. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  5. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is...

  6. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is...

  7. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  8. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  9. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  10. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  11. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  12. 21 CFR 137.285 - Degerminated yellow corn meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  13. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is...

  14. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  15. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is...

  16. 21 CFR 137.215 - Yellow corn flour.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is...

  17. 21 CFR 137.275 - Yellow corn meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  18. Is the Yellow Light Long Enough?

    ERIC Educational Resources Information Center

    Salow, Robert; And Others

    1993-01-01

    Describes an activity to determine whether the length of the yellow (warning) signal of a traffic light provides adequate time to stop or pass through the intersection. Discusses the necessary equations, mathematics, and subsequent graphs. (MVL)

  19. Assessing Sites for Yellow Legged Frog

    USGS Multimedia Gallery

    Assessing suitable sites in southern California for reintroducing endangered southern mountain yellow-legged frogs, USGS scientists rediscovered a population in the San Jacinto Wilderness, 50 years since this frog was last seen there....

  20. Lost Trust: A Yellow Fever Patient Response

    PubMed Central

    Runge, John S.

    2013-01-01

    In the 19th century, yellow fever thrived in the tropical, urban trade centers along the American Gulf Coast. Industrializing and populated, New Orleans and Memphis made excellent habitats for the yellow fever-carrying Aedes aegypti mosquitoes and the virulence they imparted on their victims. Known for its jaundice and black, blood-filled vomit, the malady terrorized the region for decades, sometimes claiming tens of thousands of lives during the near annual summertime outbreaks. In response to the failing medical community, a small, pronounced population of sick and healthy laypeople openly criticized the efforts to rid the Gulf region of yellow jack. Utilizing newspapers and cartoons to vocalize their opinions, these critics doubted and mocked the medical community, contributing to the regional and seasonal dilemma yellow fever posed for the American South. These sentient expressions prove to be an early example of patient distrust toward caregivers, a current problem in clinical heath care. PMID:24348220

  1. An Endangered Yellow-Legged Frog

    USGS Multimedia Gallery

    USGS biologists are leading the monitoring and reintroduction effort of the Southern California mountain yellow-legged frog -- federally listed as endangered with only 200 wild adults remaining in the mountains surrounding Los Angeles County....

  2. Turnip Yellow Mosaic Virus Structure

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The bumpy exterior of the turnip yellow mosaic virus (TYMV) protein coat, or capsid, was defined in detail by Dr. Alexander McPherson of the University of California, Irvin using protein crystallized in space for analysis on Earth. TYMV is an icosahedral virus constructed from 180 copies of the same protein arranged into 12 clusters of five proteins (pentamers), and 20 clusters of six proteins (hexamers). The final TYMV structure led to the enexpected hypothesis that the virus release its RNA by essentially chemical-mechanical means. Most viruses have farly flat coats, but in TYMV, the fold in each protein, called the jellyroll, is clustered at the points where the protein pentamers and hexamers join. The jellyrolls are almost standing on end, producing a bumpy surface with knobs at all of the pentamers and hexamers. At the inside surface of the pentamers is a void that is not present at the hexamers. The coating had been seen in early studies of TYMV, but McPhereson's atomic structure shows much more detail. The inside surface is strikingly, and unexpectedly, different than the outside. While the pentamers contain a central viod on the inside, the hexameric units contain peptides liked to each other, forming a ring or, more accurately, rings to fill the voild. Credit: Dr. Alexander McPherson, University of California, Irvine.

  3. Effect of Diameter of Saphenous Vein on Stump Length after Radiofrequency Ablation for Varicose Vein

    PubMed Central

    Kim, Jusung; Cho, Sungsin; Joh, Jin Hyun; Ahn, Hyung-Joon; Park, Ho-Chul

    2015-01-01

    Purpose: Radiofrequency ablation (RFA) has gained popularity for treatment of varicose veins. The diameter of the saphenous vein should be considered before RFA because occlusion of the vein may differ depending on its diameter. Until now, however, there have been few data about the correlation between the diameter of the saphenous vein and the stump length after RFA. The purpose of our study was to investigate its correlation. Materials and Methods: A retrospective review was performed from prospectively collected data of RFA patients between March 2009 and December 2011. Preoperatively, the saphenous vein diameter was measured. Ablation was initiated 2 cm distal from the junction. Postoperatively, stump length was measured at 1 week and 6 months. After 2 years, we measured the length from the saphenofemoral junction to the leading point of occlusion for great saphenous vein, and length from the saphenopopliteal junction to the leading point of occlusion for small saphenous vein. The paired t-test, independent t-test, and correlation analysis were used for statistical analysis. P-value <0.05 was considered statistically significant. Results: During the study period, RFA was performed in 201 patients. Endovenous heat-induced thrombosis developed in 3 patients (1.5%). After 2 years, the stump length was obtained in 74 limbs. The mean diameter and stump length of the saphenous vein were 6.71.8 mm and 12.58.5 mm, respectively. Correlation analysis showed that the Pearson correlation coefficient of these factors was ?0.017. Conclusion: There was no correlation between the diameter of saphenous vein and stump length. PMID:26719839

  4. Laboratory Simulations and Spectral Analyses of Recurring Slope Streaks on Mars

    NASA Astrophysics Data System (ADS)

    Wing, B.; Irvin, B.; Hibbitts, C.; Mushkin, A.

    2014-12-01

    Low albedo streaks on Martian slopes have been cited as possible evidence for present-day intermittent and repeated surface flow of water, or brine (Mushkin et al., 2010). Also termed as Recurring Slope Lineae (1), such streaks can grow, fade, and recur repeatedly on the same slopes. Although distinguishable by being darker than surrounding terrain slope streaks have no diagnostic spectral absorption features (2). A leading hypothesis is formation by multiple wetting and drying events. Laboratory investigations have previously explored this possibility (e.g 3). When wetted with brines, soils darken, but as the sample dries, it brightens again. Wetting also results in absorption bands near 1.5 and 2 microns, which are not detected in spectra of slope streaks. Additionally, dried brines of most salts such as MgSO4, or other sulfates and many chlorides are brighter than Martian soils. However, iron chlorides are a salt that have lower albedo than most other salts and may present a mechanism for darkening slope streaks without inducing a spectral absorption feature. To explore this hypothesis, we have begun to conduct experiments investigating the spectra of iron chloride chloride solutions wetting palagonite and subsequently drying under Martian atmospheric conditions. Preliminary experiments demonstrate that FeIII chloride dried onto palagonite has no absorption features in the NIR and SWIR and remains dark and red. However, these chlorides will oxidize under terrestrial conditions forming Fe2O3 as they dry. We have constructed an environmental chamber that mimics Martian oxygen fugacity though a combination of vacuum and N2 purging, allowing for sample wetting and drying while concurrently taking spectra from 0.4 to 2.4 microns. Results from this experimental setup under Martian atmospheric conditions will be presented. References: (1) McEwen et al., (2011) Science, 333, 740-743, (2) Mushkin et al., (2010) Geophys. Res. Lett., 37, L22201, doi: 10.1029/2010GL044535, (3) Masse et al., (2012), 43rd LPSC, #1856.

  5. Endovascular Laser Therapy for Varicose Veins

    PubMed Central

    2010-01-01

    Executive Summary Objective The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and costeffectiveness of endovascular laser therapy (ELT) for the treatment of primary symptomatic varicose veins (VV). Background The Ontario Health Technology Advisory Committee (OHTAC) met on November 27, 2009 to review the safety, effectiveness, durability and cost-effectiveness of ELT for the treatment of primary VV based on an evidence-based review by the Medical Advisory Secretariat (MAS). Clinical Condition VV are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad or worse as other chronic diseases such as back pain and arthritis. Lower limb VV is a common disease affecting adults and estimated to be the seventh most common reason for physician referral in the US. There is a strong familial predisposition to VV with the risk in offspring being 90% if both parents affected, 20% when neither is affected, and 45% (25% boys, 62% girls) if one parent is affected. Globally, the prevalence of VV ranges from 5% to 15% among men and 3% to 29% among women varying by the age, gender and ethnicity of the study population, survey methods and disease definition and measurement. The annual incidence of VV estimated from the Framingham Study was reported to be 2.6% among women and 1.9% among men and did not vary within the age range (40-89 years) studied. Approximately 1% of the adult population has a stasis ulcer of venous origin at any one time with 4% at risk. The majority of leg ulcer patients are elderly with simple superficial vein reflux. Stasis ulcers are often lengthy medical problems and can last for several years and, despite effective compression therapy and multilayer bandaging are associated with high recurrence rates. Recent trials involving surgical treatment of superficial vein reflux have resulted in healing and significantly reduced recurrence rates. Endovascular Laser Therapy for VV ELT is an image-guided, minimally invasive treatment alternative to surgical stripping of superficial venous reflux. It does not require an operating room or general anesthesia and has been performed in outpatient settings by a variety of medical specialties including surgeons (vascular or general), interventional radiologists and phlebologists. Rather than surgically removing the vein, ELT works by destroying, cauterizing or ablating the refluxing vein segment using heat energy delivered via laser fibre. Prior to ELT, colour-flow Doppler ultrasonography is used to confirm and map all areas of venous reflux to devise a safe and effective treatment plan. The ELT procedure involves the introduction of a guide wire into the target vein under ultrasound guidance followed by the inse

  6. Splenic Vein Thrombosis with Oesophageal Varices: A Late Complication of Umbilical Vein Catheterization

    PubMed Central

    Vos, L. J. M.; Potocky, V.; Brker, F. H. L.; Vries, J. A. De; Postma, L.; Edens, E.

    1974-01-01

    On the basis of observations made on three infants, a description is given of a late complication of umbilical vein catheterization not hitherto reported. The children showed the symptoms of thrombosis of the splenic vein with secondary splenomegaly and marked gastric and/or esophageal varices, while the portal vein showed no abnormality. The diagnosis was preoperatively established by means of selective angiography of the superior mesenteric artery and the splenic artery. Treatment in these three cases consisted of splenectomy, with good clinical and radiological results. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4.Fig. 5.Fig. 6. PMID:4842977

  7. Axillary vein thrombosis mimicking muscular strain.

    PubMed Central

    Louis, J

    1999-01-01

    Axillary vein thrombosis may occur on strenuous activity with a clinical picture similar to a simple strain. It carries significant morbidity but a good outcome is possible with early treatment. The aetiology, investigation, and treatment are discussed. Images Figure 1 Figure 1 PMID:10353060

  8. Complete guidewire retention after femoral vein catheterization.

    PubMed

    Cat, Bahar Gulcay; Guler, Sertac; Soyuduru, Murat; Guven, Ibrahim; Ramadan, Hayri

    2015-01-01

    Central venous catheters (CVCs) are often used for various purposes in the emergency departments (ED). The main uses of CVCs in the EDs are emergent hemodialysis, in situations where peripheral vein catheterization cannot be achieved, and continuous invasive hemodynamic monitoring. The complications related to CVC insertion are usually mechanical and observed in the near term after the procedure. Retained CVC guidewire after catheterization is a rare complication in the published reports and usually related with intra- or postoperative settings and jugular or subclavian vein. The present study reported a young female patient who underwent left femoral vein catheterization 6 months earlier in an intensive care unit of another hospital and was diagnosed with complete guidewire retention in the ED. To the best of the authors' knowledge, this is the first case in published reports with a diagnosis of retained CVC guidewire with retrograde migration into the femoral vein. Surprisingly, the patient developed no thrombotic or embolic complication during this 6-month period. PMID:26657235

  9. Hepatic myospherulosis complicating portal vein embolisation

    PubMed Central

    Lui, P C W; Luk, I S C; Lee, C K L; Lui, Y H; Leung, C Y; Choi, C H

    2004-01-01

    Aims: Myospherulosis is a rare condition characterised by sac-like structures containing spheroid bodies in cysts or cystic spaces in the tissue. This condition has not previously been reported in the liver. The association with previous portal vein embolisation using a mixture of butyl 2-cyanoacrylate and ethiodised oil and the proposed mechanism of pathogenesis are discussed. Methods: Samples from 8 patients treated by hepatectomy after portal vein embolisation using a mixture of butyl 2-cyanoacrylate and ethiodised oil were retrieved from the archives of the United Christian Hospital, Hong Kong. The histological specimens were reviewed. A panel of histochemical and immunohistochemical stains was used. Results: All cases showed hepatic myospherulosis within the veins. The veins were denuded of endothelium, which was replaced by granulation tissue and fibrous tissue with a lymphoplasmacytic infiltrate. Foreign body-type giant cells (six cases) and eosinophilic infiltrates (seven cases) were noted in most cases. Both parent bodies and endobodies were stained red by Papanicolaou and Massons trichrome and stained blue by solochrome cyanine. The endobodies showed immunoreactivity towards glycophorin A. They were negative for Alcian blue, periodic acid Schiff, Grocott, and Ziehl-Neelsen stains. Conclusions: The endobodies of myospherulosis may be misdiagnosed as fungi or algae by the unwary. The clinical history, intravascular location, lack of staining with periodic acid Schiff and Grocott stains, and positive glycophorin A staining are generally sufficient for a confident diagnosis of myospherulosis. PMID:14747440

  10. How Is Deep Vein Thrombosis Diagnosed?

    MedlinePLUS

    ... check your blood pressure and your heart and lungs. Diagnostic Tests Your doctor may recommend tests to find out whether you have DVT. Common Tests The most common test for diagnosing deep vein blood clots is ultrasound. This test uses sound waves to create pictures ...

  11. Endoscopic vein harvesting: technique, outcomes, concerns & controversies

    PubMed Central

    Sarang, Zubair

    2013-01-01

    The choice of the graft conduit for coronary artery bypass grafting (CABG) has significant implications both in the short- and long-term. The patency of a coronary conduit is closely associated with an uneventful postoperative course, better long-term patient survival and superior freedom from re-intervention. The internal mammary artery is regarded as the primary conduit for CABG patients, given its association with long-term patency and survival. However, long saphenous vein (LSV) continues to be utilized universally as patients presenting for CABG often have multiple coronary territories requiring revascularization. Traditionally, the LSV has been harvested by creating incisions from the ankle up to the groin termed open vein harvesting (OVH). However, such harvesting methods are associated with incisional pain and leg wound infections. In addition, patients find such large incisions to be cosmetically unappealing. These concerns regarding wound morbidity and patient satisfaction led to the emergence of endoscopic vein harvesting (EVH). Published experience comparing OVH with EVH suggests decreased wound related complications, improved patient satisfaction, shorter hospital stay, and reduced postoperative pain at the harvest site following EVH. Despite these reported advantages concerns regarding risk of injury at the time of harvest with its potential detrimental effect on vein graft patency and clinical outcomes have prevented universal adoption of EVH. This review article provides a detailed insight into the technical aspects, outcomes, concerns, and controversies associated with EVH. PMID:24251019

  12. Endoscopic vein harvesting: technique, outcomes, concerns & controversies.

    PubMed

    Raja, Shahzad G; Sarang, Zubair

    2013-11-01

    The choice of the graft conduit for coronary artery bypass grafting (CABG) has significant implications both in the short- and long-term. The patency of a coronary conduit is closely associated with an uneventful postoperative course, better long-term patient survival and superior freedom from re-intervention. The internal mammary artery is regarded as the primary conduit for CABG patients, given its association with long-term patency and survival. However, long saphenous vein (LSV) continues to be utilized universally as patients presenting for CABG often have multiple coronary territories requiring revascularization. Traditionally, the LSV has been harvested by creating incisions from the ankle up to the groin termed open vein harvesting (OVH). However, such harvesting methods are associated with incisional pain and leg wound infections. In addition, patients find such large incisions to be cosmetically unappealing. These concerns regarding wound morbidity and patient satisfaction led to the emergence of endoscopic vein harvesting (EVH). Published experience comparing OVH with EVH suggests decreased wound related complications, improved patient satisfaction, shorter hospital stay, and reduced postoperative pain at the harvest site following EVH. Despite these reported advantages concerns regarding risk of injury at the time of harvest with its potential detrimental effect on vein graft patency and clinical outcomes have prevented universal adoption of EVH. This review article provides a detailed insight into the technical aspects, outcomes, concerns, and controversies associated with EVH. PMID:24251019

  13. Why Do Some Pregnant Women Get Varicose Veins?

    MedlinePLUS

    ... Bullies Pregnant? What to Expect Why Do Some Pregnant Women Get Varicose Veins? KidsHealth > Parents > Q&As > Pregnancy & Infants > Why Do Some Pregnant Women Get Varicose Veins? Print A A A Text ...

  14. Fenethylline as a possible etiology for retinal vein occlusion.

    PubMed

    Al-Ghadyan, A; Rushood, A A; Alhumeidan, A A

    2009-01-01

    We are report 3 cases of hemorrhagic central retina vein occlusion following continuous use of fenethylline hydrochloride. The hemorrhage, the edema and the engorged veins showed marked improvement after discontinuing the drug and laser supplement in one case. PMID:20214057

  15. Anatomical variation of the inferior mesenteric vein's drainage pattern

    NASA Astrophysics Data System (ADS)

    Zilaie, Mina

    The purpose of this project is to report the variable drainage pattern of the inferior mesenteric vein (IMV) as reported by medical students' observations recorded on anatomical variation data sheets (n = 192). A meta-analysis on the drainage pattern of the inferior mesenteric vein as described in various anatomy resources was conducted (n = 40). The inferior mesenteric vein was observed to drain into the splenic vein, the superior mesenteric vein, and the junction between the superior mesenteric vein and the splenic vein. Anatomy resources do not commonly report all three drainage sites. It is imperative that all these common drainage sites of the inferior mesenteric vein are stated in anatomy resources, so that students are taught realistic human anatomy including its common variations.

  16. What Are the Signs and Symptoms of Varicose Veins?

    MedlinePLUS

    ... around the varicose vein. Signs of telangiectasias are clusters of red veins that you can see just under the surface of your skin. These clusters usually are found on the upper body, including ...

  17. What Are the Signs and Symptoms of Deep Vein Thrombosis?

    MedlinePLUS

    ... Twitter. What Are the Signs and Symptoms of Deep Vein Thrombosis? The signs and symptoms of deep ... serious, possibly life-threatening problems if not treated. Deep Vein Thrombosis Only about half of the people ...

  18. Comparison between mechanical properties of human saphenous vein and umbilical vein

    PubMed Central

    2012-01-01

    Background As a main cause of mortality in developed countries, Coronary Artery Disease (CAD) is known as silent killer with a considerable cost to be dedicated for its treatment. Coronary Artery Bypass Graft (CABG) is a common remedy for CAD for which different blood vessels are used as a detour. There is a lack of knowledge about mechanical properties of human blood vessels used for CABG, and while these properties have a great impact on long-term patency of a CABG. Thus, studying these properties, especially those of human umbilical veins which have not been considered yet, looks utterly necessary. Methods Umbilical vein, as well as human Saphenous vein, are respectively obtained after cesarean and CABG. First, histological tests were performed to investigate different fiber contents of the samples. Having prepared samples carefully, force-displacement results of samples were rendered to real stressstrain measurements and then a fourth-order polynomial was used to prove the non-linear behavior of these two vessels. Results Results were analyzed in two directions, i.e. circumferentially and longitudinally, which then were compared with each other. The comparison between stiffness and elasticity of these veins showed that Saphenous veins stiffness is much higher than that of umbilical vein and also, it is less stretchable. Furthermore, for both vessels, longitudinal stiffness was higher than that of circumferential and in stark contrast, stretch ratio in circumferential direction came much higher than longitudinal orientation. Conclusion Blood pressure is very high in the region of aorta, so there should be a stiff blood vessel in this area and previous investigations showed that stiffer vessels would have a better influence on the flow of bypass. To this end, the current study has made an attempt to compare these two blood vessels stiffness, finding that Saphenous vein is stiffer than umbilical vein which is somehow as stiff as rat aortic vessels. As blood vessels stiffness is directly related to elastin and mainly collagen content, results showed the lower amount of these two contents in umbilical vein regarding Saphenous vein. PMID:22917177

  19. Adventitial cystic disease of the common femoral vein presenting as deep vein thrombosis.

    PubMed

    Kim, Young-Kyun; Chun, Ho Jong; Hwang, Jeong Kye; Kim, Ji Il; Kim, Sang Dong; Park, Sun-Cheol; Moon, In Sung

    2013-08-23

    Adventitial cystic disease of the common femoral vein is a rare condition. We herein report the case of a 50-year-old woman who presented with painless swelling in her left lower leg that resembled deep vein thrombosis. She underwent femoral exploration and excision of the cystic wall. The presentation, investigation, treatment, and pathology of this condition are discussed with a literature review. PMID:23978427

  20. Yellow nails, lymphedema and chronic cough: Yellow nail syndrome in an eight-year-old girl

    PubMed Central

    Siddiq, Ishita; Hughes, Daniel

    2012-01-01

    Yellow nail syndrome is a rare disease and reported mainly in adults. A case of yellow nail syndrome involving an eight-year-old girl with associated discoloured yellowish nails on the fingers and toes, lymphedema and chronic cough, and sputum production is reported. PMID:22332131

  1. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  2. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  3. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  4. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  5. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  6. 21 CFR 870.4885 - External vein stripper.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External vein stripper. 870.4885 Section 870.4885...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Surgical Devices 870.4885 External vein stripper. (a) Identification. An external vein stripper is an extravascular device used to remove a section...

  7. Hydrops fetalis associated with chorioangioma and thrombosis of umbilical vein.

    PubMed

    Sivasli, Ercan; Tekşam, Ozlem; Haliloğlu, Mithat; Güçer, Safak; Orhan, Diclehan; Gürgey, Aytemiz; Tekinalp, Gülsevin

    2009-01-01

    Placental chorioangioma and thrombosis of an umbilical vein varix are rare etiologic factors of non-immune hydrops fetalis. Herein, we report a patient who had hydrops fetalis associated with placental chorioangioma and thrombosis of an umbilical vein varix. This is the first report of coexistence of non-immune hydrops fetalis with placental chorioangioma and thrombosis of an umbilical vein varix. PMID:20112613

  8. Retinal vein-to-vein anastomoses in Sturge-Weber syndrome documented by ultra-widefield fluorescein angiography.

    PubMed

    Quan, Ann V; Moore, Grant H; Tsui, Irena

    2015-06-01

    We report the case of a 6-year-old boy with Sturge-Weber syndrome and unilateral glaucoma in his left eye. He was born with a port wine mark involving his upper left eyelid. On ultra-widefield fluorescein angiography, he was found to have several vein-to-vein anastomoses in his left retina. To our knowledge, this is the first documentation of retinal vein-to-vein anastomoses in Sturge-Weber syndrome. PMID:25944745

  9. Transcutaneous laser treatment of leg veins.

    PubMed

    Meesters, Arne A; Pitassi, Luiza H U; Campos, Valeria; Wolkerstorfer, Albert; Dierickx, Christine C

    2014-03-01

    Leg telangiectasias and reticular veins are a common complaint affecting more than 80% of the population to some extent. To date, the gold standard remains sclerotherapy for most patients. However, there may be some specific situations, where sclerotherapy is contraindicated such as needle phobia, allergy to certain sclerosing agents, and the presence of vessels smaller than the diameter of a 30-gauge needle (including telangiectatic matting). In these cases, transcutaneous laser therapy is a valuable alternative. Currently, different laser modalities have been proposed for the management of leg veins. The aim of this article is to present an overview of the basic principles of transcutaneous laser therapy of leg veins and to review the existing literature on this subject, including the most recent developments. The 532-nm potassium titanyl phosphate (KTP) laser, the 585-600-nm pulsed dye laser, the 755-nm alexandrite laser, various 800-983-nm diode lasers, and the 1,064-nm neodymium yttrium-aluminum-garnet (Nd:YAG) laser and various intense pulsed light sources have been investigated for this indication. The KTP and pulsed dye laser are an effective treatment option for small vessels (<1 mm). The side effect profile is usually favorable to that of longer wavelength modalities. For larger veins, the use of a longer wavelength is required. According to the scarce evidence available, the Nd:YAG laser produces better clinical results than the alexandrite and diode laser. Penetration depth is high, whereas absorption by melanin is low, making the Nd:YAG laser suitable for the treatment of larger and deeply located veins and for the treatment of patients with dark skin types. Clinical outcome of Nd:YAG laser therapy approximates that of sclerotherapy, although the latter is associated with less pain. New developments include (1) the use of a nonuniform pulse sequence or a dual-wavelength modality, inducing methemoglobin formation and enhancing the optical absorption properties of the target structure, (2) pulse stacking and multiple pass laser treatment, (3) combination of laser therapy with sclerotherapy or radiofrequency, and (4) indocyanin green enhanced laser therapy. Future studies will have to confirm the role of these developments in the treatment of leg veins. The literature still lacks double-blind controlled clinical trials comparing the different laser modalities with each other and with sclerotherapy. Such trials should be the focus of future research. PMID:24220848

  10. Temporal resolution limit estimation of x-ray streak cameras using a CsI photocathode

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Gu, Li; Zong, Fangke; Zhang, Jingjin; Yang, Qinlao

    2015-08-01

    A Monte Carlo model is developed and implemented to calculate the characteristics of x-ray induced secondary electron (SE) emission from a CsI photocathode used in an x-ray streak camera. Time distributions of emitted SEs are investigated with an incident x-ray energy range from 1 to 30 keV and a CsI thickness range from 100 to 1000 nm. Simulation results indicate that SE time distribution curves have little dependence on the incident x-ray energy and CsI thickness. The calculated time dispersion within the CsI photocathode is about 70 fs, which should be the temporal resolution limit of x-ray streak cameras that use CsI as the photocathode material.

  11. New ultra fast x-ray streak camera for the advanced laser light source facility

    NASA Astrophysics Data System (ADS)

    Martel, C.; Fourmaux, S.; Lecherbourg, L.; Bandulet, H.; Kieffer, J. C.

    2007-09-01

    The Advanced Laser Light Source (ALLS) infrastructure is a new state-of-the-art multi-beams femtosecond laser facility currently in operation at INRS near Montreal, Canada. The use of a wide range of energy radiation from hard x-ray up to infrared light on the ultrafast time scale requires the development of ultrafast detector diagnostics tools to study the emission spectrum of these sources. To fulfill these requirements, new streak cameras have been developed for ALLS facility. We present the new FXR streak camera which has been specifically developed for ALLS and which is dedicated to x-ray spectroscopy with sub-picosecond time resolution combined with a very high spatial resolution.

  12. Streaked radiography of an irradiated foam sample on the National Ignition Facility

    SciTech Connect

    Cooper, A. B. R.; Schneider, M. B.; MacLaren, S. A.; Young, P. E.; Hsing, W. W.; Seugling, R.; Foord, M. E.; Sain, J. D.; May, M. J.; Marrs, R. E.; Maddox, B. R.; Lu, K.; Dodson, K.; Smalyuk, V.; Moore, A. S.; Graham, P.; Foster, J. M.; Back, C. A.; Hund, J. F.

    2013-03-15

    Streaked x-ray radiography images of annular patterns in an evolving tantalum oxide foam under the influence of a driven, subsonic radiation wave were obtained on the National Ignition Facility. This is the first successful radiography measurement of the evolution of well-defined foam features under a driven, subsonic wave in the diffusive regime. A continuous record of the evolution was recorded on an x-ray streak camera, using a slot-apertured point-projection backlighter with an 8 ns nickel source (7.9 keV). Radiography images were obtained for four different annular patterns, which were corrected using a source-dependent flat-field image. The evolution of the foam features was well-modeled using the 3D KULL radiation hydrodynamics code. This experimental and modeling platform can be modified for scaled high-energy-density laboratory astrophysics experiments.

  13. Single-shot visualization of evolving laser wakefields using an all-optical streak camera.

    PubMed

    Li, Zhengyan; Tsai, Hai-En; Zhang, Xi; Pai, Chih-Hao; Chang, Yen-Yu; Zgadzaj, Rafal; Wang, Xiaoming; Khudik, V; Shvets, G; Downer, M C

    2014-08-22

    We visualize ps-time-scale evolution of an electron density bubble--a wake structure created in atmospheric density plasma by an intense ultrashort laser pulse--from the phase "streak" that the bubble imprints onto a probe pulse that crosses its path obliquely. Phase streaks, recovered in one shot using frequency-domain interferometric techniques, reveal the formation, propagation, and coalescence of the bubble within a 3 mm long ionized helium gas target. 3D particle-in-cell simulations validate the observed density-dependent bubble evolution, and correlate it with the generation of a quasimonoenergetic ? 100 MeV electron beam. The results provide a basis for understanding optimized electron acceleration at a plasma density n(e) ? 2 10(19) cm(-3), inefficient acceleration at lower density, and dephasing limits at higher density. PMID:25192102

  14. A novel compact high speed x-ray streak camera (invited)

    SciTech Connect

    Hares, J. D.; Dymoke-Bradshaw, A. K. L.

    2008-10-15

    Conventional in-line high speed streak cameras have fundamental issues when their performance is extended below a picosecond. The transit time spread caused by both the spread in the photoelectron (PE) ''birth'' energy and space charge effects causes significant electron pulse broadening along the axis of the streak camera and limits the time resolution. Also it is difficult to generate a sufficiently large sweep speed. This paper describes a new instrument in which the extraction electrostatic field at the photocathode increases with time, converting time to PE energy. A uniform magnetic field is used to measure the PE energy, and thus time, and also focuses in one dimension. Design calculations are presented for the factors limiting the time resolution. With our design, subpicosecond resolution with high dynamic range is expected.

  15. Upgrades to the VISAR-streaked optical pyrometer (SOP) system on NIF

    NASA Astrophysics Data System (ADS)

    Manuel, A. M.; Millot, M.; Seppala, L. G.; Frieders, G.; Zeid, Z.; Christensen, K.; Celliers, P. M.

    2015-08-01

    The Velocity Interferometer System for Any Reflector (VISAR) is a critical diagnostic in Inertial Confinement Fusion and High Energy Density research as it has the ability to track shock fronts or interfaces moving 0.1-100 km/s with great accuracy. At the National Ignition Facility (NIF), the VISAR has recently been used successfully for implosion tuning and equation of state measurements. However, the initial design of the companion Streaked Optical Pyrometer (SOP) to measure spectral radiance - hence shock temperature - suffers from large background levels and poor spatial resolution. We report on an upgrade to improve the spatial resolution in the 560-640nm band by using custom lenses and replacing the Dove prism with a K-mirror and implementing a gating-circuit for the streak camera to reduce background signal. We envision that upgraded SOP will provide high quality data collection matching NIF VISAR's standards.

  16. Effects of diabatic heating on the ageostrophic circulation of an upper tropospheric jet streak

    NASA Technical Reports Server (NTRS)

    Keyser, D. A.; Johnson, D. R.

    1982-01-01

    Interaction between the mass circulation within a mesoscale convective complex (MCC) and a direct mass circulation in the entrance region of an upper tropospheric polar jet streak was examined within the isentropic structure to investigate mechanisms responsible for linking these two scales of motion. The results establish that latent heating in the MCC modifies the direct mass circulation in the jet streak entrance region through the diabatically induced components of ageostrophic motion analyzed within isentropic coordinates. Within the strong mesoscale mass circulation of each MCC, strong horizontal mass flux convergence into the MCC at low levels is balanced by strong horizontal mass flux divergence away from the convergence at upper levels. Locations of large diabatic heating rates correspond well to the MCC position for each case; diabatic heating forces the upward vertical branch for the mesoscale mass circulation.

  17. Motion Streaks Do Not Influence the Perceived Position of Stationary Flashed Objects

    PubMed Central

    Pavan, Andrea; Bellacosa Marotti, Rosilari

    2012-01-01

    In the present study, we investigated whether motion streaks, produced by fast moving dots Geisler 1999, distort the positional map of stationary flashed objects producing the well-known motion-induced position shift illusion (MIPS). The illusion relies on motion-processing mechanisms that induce local distortions in the positional map of the stimulus which is derived by shape-processing mechanisms. To measure the MIPS, two horizontally offset Gaussian blobs, placed above and below a central fixation point, were flashed over two fields of dots moving in opposite directions. Subjects judged the position of the top Gaussian blob relative to the bottom one. The results showed that neither fast (motion streaks) nor slow moving dots influenced the perceived spatial position of the stationary flashed objects, suggesting that background motion does not interact with the shape-processing mechanisms involved in MIPS. PMID:22645464

  18. Mach-zehnder based optical marker/comb generator for streak camera calibration

    SciTech Connect

    Miller, Edward Kirk

    2015-03-03

    This disclosure is directed to a method and apparatus for generating marker and comb indicia in an optical environment using a Mach-Zehnder (M-Z) modulator. High speed recording devices are configured to record image or other data defining a high speed event. To calibrate and establish time reference, the markers or combs are indicia which serve as timing pulses (markers) or a constant-frequency train of optical pulses (comb) to be imaged on a streak camera for accurate time based calibration and time reference. The system includes a camera, an optic signal generator which provides an optic signal to an M-Z modulator and biasing and modulation signal generators configured to provide input to the M-Z modulator. An optical reference signal is provided to the M-Z modulator. The M-Z modulator modulates the reference signal to a higher frequency optical signal which is output through a fiber coupled link to the streak camera.

  19. Time-Resolved Spectra of Dense Plasma Focus Using Spectrometer, Streak Camera, CCD Combination

    SciTech Connect

    F. J. Goldin, B. T. Meehan, E. C. Hagen, P. R. Wilkins

    2010-10-01

    A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially CzernyTurner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments.

  20. X-ray streak camera temporal resolution improvement using a longitudinal time-dependent field

    SciTech Connect

    Qiang, Ji; Qiang, J.; Byrd, J.M.; Feng, J.; Huang, G.

    2008-05-09

    X-ray streak cameras (XSC) have been known to be one of the fastest detectors forultrafast X-ray science. A number of applications in material science, biochemistry, accelerator physics, require sub-picosecond resolution to study new phenomena. Inthis paper, we report on a new method which can potentially improve the temporal resolution of a streak camera down to 100 femtoseconds. This method uses a time-dependent acceleration field to lengthen the photoelectron bunch, significantlyimproving the time resolution as well as reducing the time dispersion caused byinitial energy spread and the effects fromthe space charge forces. A computer simulation of an XSC using this method shows significant improvement in the resolution.