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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. Epidemiology of Blackberry yellow vein associated virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackberry yellow vein disease is one of the most important diseases of blackberry in the United States. Several viruses are found associated with the symptomology but Blackberry yellow vein associated virus (BYVaV) appears to be the most prevalent of all, leading to the need for a better understand...

  4. 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...

  5. The Incidence and Ecology of Blackberry yellow vein associated virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Symptoms of vein yellowing and bush decline in blackberry were attributed to infection by a novel crinivirus named Blackberry yellow vein associated virus (BYVaV). The disease is an emerging threat to blackberry production as it can cause substantial yield loss. The objective of this study was to id...

  6. 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....

  7. 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...

  8. 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...

  9. 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...

  10. 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 ...

  11. 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

  12. A tymovirus from Calopogonium mucunoides in Malaysia is not clitoria yellow vein tymovirus.

    PubMed

    Gibbs, A J; Mackenzie, A M; Abdul-Samad, N

    1997-01-01

    A tymoyirus isolated from Malaysian crops of Calopogonium mucunoides has been shown to have virions that are serologically indistinguishable from those of clitoria yellow vein tymovirus. We have sequenced the virion protein (VP) gene of the virus and have found that although it is a member of the cluster that includes CYVV, it is the most distinct member of that cluster (< 62% sequence identity with all the others), and is clearly a separate species, which we propose should be named calopogonium yellow vein virus. Most of the serological specificity of the virions of tymoviruses seems to reside in the C-terminal hexapeptide of the virion protein. PMID:9672629

  13. 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...

  14. First report of Squash vein yellowing virus in watermelon in Guatemala

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline in Central America. Symptoms including wilt and collapse of plants at harvest, and non-marketable fruits with internal rind necrosis were observed. This report provides an overview o...

  15. First report of Squash vein yellowing virus in Watermelon in Guatemala

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline in Central America. Symptoms including wilt and collapse of plants at harvest, and non-marketable fruits with internal rind necrosis were observed. This report provides an overview o...

  16. First Complete Genome Sequence of Pepper vein yellows virus from Australia

    PubMed Central

    Maina, Solomon; Edwards, Owain R.

    2016-01-01

    We present here the first complete genomic RNA sequence of the polerovirus Pepper vein yellows virus (PeVYV) obtained from a pepper plant in Australia. We compare it with complete PeVYV genomes from Japan and China. The Australian genome was more closely related to the Japanese than the Chinese genome. PMID:27231375

  17. 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...

  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. 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...

  20. 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...

  1. 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...

  2. First Complete Genome Sequence of Pepper vein yellows virus from Australia.

    PubMed

    Maina, Solomon; Edwards, Owain R; Jones, Roger A C

    2016-01-01

    We present here the first complete genomic RNA sequence of the polerovirus Pepper vein yellows virus (PeVYV) obtained from a pepper plant in Australia. We compare it with complete PeVYV genomes from Japan and China. The Australian genome was more closely related to the Japanese than the Chinese genome. PMID:27231375

  3. 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...

  4. 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

  5. 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

  6. 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

  7. 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...

  8. 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

  9. 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

  10. 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...

  11. 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...

  12. Transmission of Squash vein yellowing virus to and From Cucurbit Weeds and Effects on Sweetpotato Whitefly (Hemiptera: Aleyrodidae) Behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several common cucurbit weed reservoirs for Squash vein yellowing virus (SqVYV) were compared with watermelons as sources of inoculum. Weed susceptibility to SqVYV was also analyzed. In addition, behavior of the whitefly vector of SqVYV was studied on infected and non-infected plants. This report...

  13. 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...

  14. 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...

  15. 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 ...

  16. 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...

  17. 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...

  18. 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 ...

  19. 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 ...

  20. 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...

  1. Genetic diversity and population structure of beet necrotic yellow vein virus in China.

    PubMed

    Zhuo, Na; Jiang, Ning; Zhang, Chao; Zhang, Zong-Ying; Zhang, Guo-Zhen; Han, Cheng-Gui; Wang, Ying

    2015-07-01

    Beet necrotic yellow vein virus (BNYVV) is a serious threat to the sugar beet industry worldwide. However, little information is available regarding the genetic diversity and population structure of BNYVV in China. Here, we analyzed multiple sequences from four genomic regions (CP, RNA3, RNA4 and RNA5) of a set of Chinese isolates. Sequence analyses revealed that several isolates were mixed infections of variants with different genotypes and/or different p25 tetrad motifs. In total, 12 distinct p25 tetrads were found in the Chinese BNYVV population, of which four tetrads were newly identified. Phylogenetic analyses based on four genes (CP, RNA3-p25, RNA4-p31 and RNA5-p26) in isolates from around the world revealed the existence of two to four groups, which mostly corresponded to previously reported phylogenetic groups. Two new subgroups and a new group were identified from the Chinese isolates in p25 and p26 trees, respectively. Selection pressure analysis indicated that there was a positive selection pressure on the p25 from the Chinese isolates, but the other three proteins were under a negative selection pressure. There was frequent gene flow between geographically distant populations, which meant that BNYVV populations from different provinces were not geographically differentiated. PMID:25997927

  2. 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....

  3. Association of an Alphasatellite with Tomato Yellow Leaf Curl Virus and Ageratum Yellow Vein Virus in Japan is Suggestive of a Recent Introduction

    PubMed Central

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W.; Natsuaki, Keiko T.

    2014-01-01

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB), a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed. PMID:24424499

  4. Association of an alphasatellite with tomato yellow leaf curl virus and ageratum yellow vein virus in Japan is suggestive of a recent introduction.

    PubMed

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W; Natsuaki, Keiko T

    2014-01-01

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB), a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed. PMID:24424499

  5. Bean yellow mosaic, clover yellow vein, and pea mosaic are distinct potyviruses: evidence from coat protein gene sequences and molecular hybridization involving the 3' non-coding regions.

    PubMed

    Tracy, S L; Frenkel, M J; Gough, K H; Hanna, P J; Shukla, D D

    1992-01-01

    The sequences of the 3' 1019 nucleotides of the genome of an atypical strain of bean yellow mosaic virus (BYMV-S) and of the 3' 1018 nucleotides of the clover yellow vein virus (CYVV-B) genome have been determined. These sequences contain the complete coding region of the viral coat protein followed by a 3' non-coding region of 173 and 178 nucleotides for BYMV-S and CYVV-B, respectively. When the deduced amino acid sequences of the coat protein coding regions were compared, a sequence identity of 77% was found between the two viruses, and optimal alignment of the 3' untranslated regions of BYMV-S and CYVV-B gave a 65% identity. However, the degree of homology of the amino acid sequences of coat proteins of BYMV-S with the published sequences for three other strains of BYMV ranged from 88% to 94%, while the sequence homology of the 3' untranslated regions between the four strains of BYMV ranged between 86% and 95%. Amplified DNA probes corresponding to the 3' non-coding regions of BYMV-S and CYVV-B showed strong hybridization only with the strains of their respective viruses and not with strains of other potyviruses, including pea mosaic virus (PMV). The relatively low sequence identities between the BYMV-S and CYVV-B coat proteins and their 3' non-coding regions, together with the hybridization results, indicate that BYMV, CYVV, and PMV are distinct potyviruses. PMID:1731696

  6. 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

  7. 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

  8. Plant reservoirs of Squash vein yellowing virus, causal agent of viral watermelon vine decline, and other whitefly-transmitted cucurbit viruses 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 sufficient to induce a watermelon vine decline and fruit rind necrosis that had been observed for several years previously. This novel virus species was shown to be whitefly-transmissible and has now ...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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 ...

  16. 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 ...

  17. 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...

  18. 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

  19. Activation of the salicylic acid signaling pathway enhances Clover yellow vein virus virulence in susceptible pea cultivars.

    PubMed

    Atsumi, Go; Kagaya, Uiko; Kitazawa, Hiroaki; Nakahara, Kenji Suto; Uyeda, Ichiro

    2009-02-01

    The wild-type strain (Cl-WT) of Clover yellow vein virus (ClYVV) systemically induces cell death in pea cv. Plant introduction (PI) 118501 but not in PI 226564. A single incompletely dominant gene, Cyn1, controls systemic cell death in PI 118501. Here, we show that activation of the salicylic acid (SA) signaling pathway enhances ClYVV virulence in susceptible pea cultivars. The kinetics of virus accumulation was not significantly different between PI 118501 (Cyn1) and PI 226564 (cyn1); however, the SA-responsive chitinase gene (SA-CHI) and the hypersensitive response (HR)-related gene homologous to tobacco HSR203J were induced only in PI 118501 (Cyn1). Two mutant viruses with mutations in P1/HCPro, which is an RNA-silencing suppressor, reduced the ability to induce cell death and SA-CHI expression. The application of SA and of its analog benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester (BTH) partially complemented the reduced virulence of mutant viruses. These results suggest that high activation of the SA signaling pathway is required for ClYVV virulence. Interestingly, BTH could enhance Cl-WT symptoms in PI 226564 (cyn1). However, it could not enhance symptoms induced by White clover mosaic virus and Bean yellow mosaic virus. Our report suggests that the SA signaling pathway has opposing functions in compatible interactions, depending on the virus-host combination. PMID:19132869

  20. 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

  1. 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

  2. [Angioid streaks].

    PubMed

    Matonti, F; Conrath, J

    2012-12-01

    Angioid streaks represent breaks in Bruch's membrane, appearing as dark or reddish radial streaks eminating from the optic disc. Usually asymptomatic, these streaks may develop neovascularisation and lead to a maculopathy with marked loss of vision. Some associations with systemic disease are classically described, especially pseudoxanthoma elasticum. This condition may involve cardiovascular complications. A mutation has been found in the ABCC6 gene, which encodes for a membrane transport protein involved in the synthesis of the extracellular matrix. Imaging allows for visualization of the extent of the streaks, and autofluorescence is particularly informative. Spectral domain OCT may also demonstrate early breaks in Bruch's membrane. Neovascular complications, previously responsible for inevitable visual impairment at some point after their occurrence, are now managed by intravitreal injections of anti-VEGFs with clear efficacity. The ophthalmologist must be aware of this condition, in order to guide the patient towards a systemic work-up if necessary, and also to insure quick and targeted treatment in the case of neovascular complications. PMID:23046745

  3. Wind Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 17 September 2003

    Bright wind streaks are present in the lee of craters and other obstacles in this image, located in Sinus Sabaeus, near the Martian equator. These streaks indicate that the local winds blow from the northeast (upper right in the image). The brightness of the streaks indicates that either bright material has been deposited in the lee of the craters, or that the surface has eroded preferentially in the lee of craters, exposing an underlying bright material. Because the streaks are bright regardless of the surrounding surface brightness, the first hypothesis most likely. The streaks probably all represent deposits of the same bright material that settled out of the atmosphere in the wind shelter provided by topographic peaks.

    Image information: VIS instrument. Latitude -6.3, Longitude 14.1 East (345.9 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the

  4. Screening and analysis of genes expressed upon infection of broad bean with Clover yellow vein virus causing lethal necrosis.

    PubMed

    Nakahara, Kenji S; Kitazawa, Hiroaki; Atsumi, Go; Choi, Sun Hee; Suzuki, Yuji; Uyeda, Ichiro

    2011-01-01

    Clover yellow vein virus (ClYVV) causes lethal systemic necrosis in legumes, including broad bean (Vicia faba) and pea (Pisum sativum). To identify host genes involved in necrotic symptom expression after ClYVV infection, we screened cDNA fragments in which expression was changed in advance of necrotic symptom expression in broad bean (V. faba cv. Wase) using the differential display technique and secondarily with Northern blot analysis. Expression changes were confirmed in 20 genes, and the six that exhibited the most change were analyzed further. These six genes included a gene that encodes a putative nitrate-induced NOI protein (VfNOI), and another was homologous to an Arabidopsis gene that encodes a glycine- and proline-rich protein GPRP (VfGPRP). We recently reported that necrotic symptom development in ClYVV-infected pea is associated with expression of salicylic acid (SA)-dependent pathogenesis-related (PR) proteins and requires SA-dependent host responses. Interestingly, VfNOI and VfGPRP expression was correlated with that of the putative SA-dependent PR proteins in ClYVV-infected broad bean. However, broad bean infected with a recombinant ClYVV expressing the VfGPRP protein showed weaker symptoms and less viral multiplication than that infected with ClYVV expressing the GFP protein. These results imply that VfGPRP plays a role in defense against ClYVV rather than in necrotic symptom expression. PMID:21767375

  5. Characterisation and epitope analysis of monoclonal antibodies to virions of clover yellow vein and Johnsongrass mosaic potyviruses.

    PubMed

    Hewish, D R; Xiao, X W; Mishra, A; Gough, K H; Shukla, D D

    1993-01-01

    Mouse monoclonal antibodies (MAbs) against the Australian B strain of clover yellow vein (ClYVV-B) and the JG strain of Johnsongrass mosaic (JGMV) potyviruses were produced, characterised and the epitopes with which they reacted were deduced. Using intact particles of ClYVV a total of ten MAbs were obtained which reacted strongly with ClYVV-B in an enzyme-linked immunosorbent assay and Western blots. Four of these MAbs (1, 2, 4, and 13) were found to be ClYVV-specific, as they reacted with all five ClYVV strains from Australia and the U.S.A. but not with 11 strains of bean yellow mosaic (BYMV), pea mosaic (PMV), and white lupin mosaic (WLMV) viruses which, together with ClYVV, form the BYMV subgroup of potyvirses. These MAbs failed to react with eight other potyvirus species, including six which infect legumes like the viruses in the BYMV subgroup. The ClYVV MAb 10 was found to be BYMV subgroup-specific. It reacted strongly with 15 of the 16 strains of viruses in the subgroup and gave no reaction with eight other potyviruses. The other five ClYVV MAbs reacted with varying degrees of specificity with the BYMV subgroup viruses and also with other potyviruses. Eight of the ClYVV MAbs (1, 2, 4, 5, 13, 17, 21, and 22) reacted with the intact coat proteins only and not with the truncated (minus amino terminus) coat protein of ClYVV suggesting that the epitopes for these MAbs are located in the surface-exposed, amino-terminal region of the ClYVV coat protein. Comparison of published coat protein sequences of BYMV and ClYVV isolates indicated that the epitopes for the four ClYVV-specific MAbs may be in the amino-terminal region spanning amino acid residues 18 to 30, whereas those for the other four MAbs may be located in the first 17 amino-terminal amino acid residue region. The epitopes that reacted with BYMV subgroup-specific MAb 10 and MAb 30 which reacted with 20 of the 24 potyvirus isolates, are probably located in the core region of ClYVV coat protein as these MAbs

  6. 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

  7. Transmission of Squash vein yellowing virus to and From Cucurbit Weeds and Effects on Sweetpotato Whitefly (Hemiptera: Aleyrodidae) Behavior.

    PubMed

    Shrestha, D; McAuslane, H J; Adkins, S T; Smith, H A; Dufault, N; Webb, S E

    2016-08-01

    Since 2003, growers of Florida watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] have periodically suffered large losses from a disease caused by Squash vein yellowing virus (SqVYV), which is transmitted by the whitefly Middle East-Asia Minor 1 (MEAM1), formerly Bemisia tabaci (Gennadius) biotype B. Common cucurbit weeds like balsam apple (Momordica charantia L.) and smellmelon [Cucumis melo var. dudaim (L.) Naud.] are natural hosts of SqVYV, and creeping cucumber (Melothria pendula L.) is an experimental host. Study objectives were to compare these weeds and 'Mickylee' watermelon as sources of inoculum for SqVYV via MEAM1 transmission, to determine weed susceptibility to SqVYV, and to evaluate whitefly settling and oviposition behaviors on infected vs. mock-inoculated (inoculated with buffer only) creeping cucumber leaves. We found that the lowest percentage of watermelon recipient plants was infected when balsam apple was used as a source of inoculum. Watermelon was more susceptible to infection than balsam apple or smellmelon. However, all weed species were equally susceptible to SqVYV when inoculated by whitefly. For the first 5 h after release, whiteflies had no preference to settle on infected vs. mock-inoculated creeping cucumber leaves. After 24 h, whiteflies preferred to settle on mock-inoculated leaves, and more eggs were laid on mock-inoculated creeping cucumber leaves than on SqVYV-infected leaves. The transmission experiments (source of inoculum and susceptibility) show these weed species as potential inoculum sources of the virus. The changing settling preference of whiteflies from infected to mock-inoculated plants could lead to rapid spread of virus in the agroecosystem. PMID:27400705

  8. Eclipta yellow vein virus enhances chlorophyll destruction, singlet oxygen production and alters endogenous redox status in Andrographis paniculata.

    PubMed

    Khan, Asifa; Luqman, Suaib; Masood, Nusrat; Singh, Dhananjay Kumar; Saeed, Sana Tabanda; Samad, Abdul

    2016-07-01

    The infection of Eclipta yellow vein virus [EcYVV-IN, Accession No. KC476655], recently reported for the first time, on Andrographis paniculata was studied for redox-mediated alteration mechanism in infected plants. A. paniculata, an important medicinal plant, is used in traditional Indian, Chinese and modern system of medicine. Andrographolide, one of the foremost components of this plant, is known for its varied pharmacological properties. Our investigation provides insight into the effect of virus-induced changes in the singlet oxygen quenching due to the alteration in pigment content (chlorophyll and carotenoids) as well as activation of plant secondary metabolism along with defense activation leading to changes in enzymatic and non-enzymatic redox status. Due to infection, a reduction in carotenoid content was observed which leads to reduced quenching of singlet oxygen. An increased level of enzymatic (SOD and APX) and non-enzymatic antioxidant (DPPH, FRAP, RP, NO, TAC and TP) activities were also observed in virus-infected plants with a positive correlation (>0.9). However, CAT activity was diminished which could be either due to its proteolytic degradation or inactivation by superoxide anions (O(2-.)), NO or peroxynitrite radicals. A significant (p < 0.05) increase in total phenolic content was observed in the infected plants while no considerable difference was seen in the total flavonoid content. Our results highlighted the alteration in redox status caused by virus-induced biotic stress on the plants and could be useful for understanding the after effects of viral infection This study could also be helpful in developing biomimetic methods for improving the production of secondary metabolites of pharmaceutical importance. PMID:27035255

  9. Adaptation from whitefly to leafhopper transmission of an autonomously replicating nanovirus-like DNA component associated with ageratum yellow vein disease.

    PubMed

    Saunders, Keith; Bedford, Ian D; Stanley, John

    2002-04-01

    Ageratum yellow vein disease is caused by the whitefly-transmitted monopartite begomovirus Ageratum yellow vein virus and a DNA beta satellite component. Naturally occurring symptomatic plants also contain an autonomously replicating nanovirus-like DNA 1 component that relies on the begomovirus and DNA beta for systemic spread and whitefly transmission but is not required for maintenance of the disease. Here, we show that systemic movement of DNA 1 occurs in Nicotiana benthamiana when co-inoculated with the bipartite begomovirus Tomato golden mosaic virus and the curtovirus Beet curly top virus (BCTV), but not with the mastrevirus Bean yellow dwarf virus. BCTV also mediates the systemic movement of DNA 1 in sugar beet, and the nanovirus-like component is transmitted between plants by the BCTV leafhopper vector Circulifer tenellus. We also describe a second nanovirus-like component, referred to as DNA 2, that has only 47% nucleotide sequence identity with DNA 1. The diversity and adaptation of nanovirus components are discussed. PMID:11907341

  10. 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

  11. Microchannel plate streak camera

    DOEpatents

    Wang, Ching L.

    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.

  12. 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.

  13. 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.

  14. 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

  15. Involvement of the P1 cistron in overcoming eIF4E-mediated recessive resistance against Clover yellow vein virus in pea.

    PubMed

    Nakahara, Kenji S; Shimada, Ryoko; Choi, Sun-Hee; Yamamoto, Haruko; Shao, Jun; Uyeda, Ichiro

    2010-11-01

    Two recessive genes (cyv1 and cyv2) are known to confer resistance against Clover yellow vein virus (ClYVV) in pea. cyv2 has recently been revealed to encode eukaryotic translation initiation factor 4E (eIF4E) and is the same allele as sbm1 and wlm against other potyviruses. Although mechanical inoculation with crude sap is rarely able to cause infection of a cyv2 pea, biolistic inoculation of the infectious ClYVV cDNA clone does. At the infection foci, the breaking virus frequently emerges, resulting in systemic infection. Here, a derived cleaved-amplified polymorphic sequence analysis showed that the breakings were associated with a single nonsynonymous mutation on the ClYVV genome, corresponding to an amino-acid substitution at position 24 (isoleucine to valine) on the P1 cistron. ClYVV with the point mutation was able to break the resistance. This is a first report demonstrating that P1 is involved in eIF4E-mediated recessive resistance. PMID:20653413

  16. Heterologous expression of viral suppressors of RNA silencing complements virulence of the HC-Pro mutant of clover yellow vein virus in pea.

    PubMed

    Atsumi, Go; Nakahara, Kenji S; Wada, Tomoko Sugikawa; Choi, Sun Hee; Masuta, Chikara; Uyeda, Ichiro

    2012-06-01

    Many plant viruses encode suppressors of RNA silencing, including the helper component-proteinase (HC-Pro) of potyviruses. Our previous studies showed that a D-to-Y mutation at amino acid position 193 in HC-Pro (HC-Pro-D193Y) drastically attenuated the virulence of clover yellow vein virus (ClYVV) in legume plants. Furthermore, RNA-silencing suppression (RSS) activity of HC-Pro-D193Y was significantly reduced in Nicotiana benthamiana. Here, we examine the effect of expression of heterologous suppressors of RNA silencing, i.e., tomato bushy stunt virus p19, cucumber mosaic virus 2b, and their mutants, on the virulence of the ClYVV point mutant with D193Y (Cl-D193Y) in pea. P19 and 2b fully and partially complemented Cl-D193Y multiplication and virulence, including lethal systemic HR in pea, respectively, but the P19 and 2b mutants with defects in their RSS activity did not. Our findings strongly suggest that the D193Y mutation exclusively affects RSS activity of HC-Pro and that RSS activity is necessary for ClYVV multiplication and virulence in pea. PMID:22398917

  17. P3N-PIPO of Clover yellow vein virus exacerbates symptoms in pea infected with white clover mosaic virus and is implicated in viral synergism.

    PubMed

    Hisa, Yusuke; Suzuki, Haruka; Atsumi, Go; Choi, Sun Hee; Nakahara, Kenji S; Uyeda, Ichiro

    2014-01-20

    Mixed infection of pea (Pisum sativum) with Clover yellow vein virus (ClYVV) and White clover mosaic virus (WClMV) led to more severe disease symptoms (a phenomenon called viral synergism). Similar to the mixed ClYVV/WClMV infection, a WClMV-based vector encoding P3N-PIPO of ClYVV exacerbated the disease symptoms. Infection with the WClMV vector encoding ClYVV HC-Pro (a suppressor of RNA silencing involved in potyviral synergisms), also resulted in more severe symptoms, although to a lesser extent than infection with the vector encoding P3N-PIPO. Viral genomic RNA accumulated soon after inoculation (at 2 and 4 days) at higher levels in leaves inoculated with WClMV encoding HC-Pro but at lower levels in leaves inoculated with WClMV encoding P3N-PIPO than in peas infected with WClMV encoding GFP. Our results suggest that ClYVV P3N-PIPO is involved in the synergism between ClYVV and WClMV during pea infection through an unknown mechanism different from suppression of RNA silencing. PMID:24418553

  18. The secondary structure of the 5'-noncoding region of beet necrotic yellow vein virus RNA 3: evidence for a role in viral RNA replication.

    PubMed Central

    Gilmer, D; Allmang, C; Ehresmann, C; Guilley, H; Richards, K; Jonard, G; Ehresmann, B

    1993-01-01

    Secondary structure-sensitive chemical and enzymatic probes have been used to produce a model for the folding of the first 312 residues of the long 5'-noncoding region of beet necrotic yellow vein virus RNA 3. The structure consists of two major domains, one of which includes long distance base-pairing interactions between two short sequence elements (Box I and Box II) situated between positions 237 and 292 and complementary elements (Box I' and II') near the 5'-terminus. Previous studies have shown that base pairing between these sequence elements (in either the plus-strand or minus-strand RNA) is important for RNA 3 accumulation during infection. RNA 3 transcripts were produced containing mutations which preferentially disrupted Box II-II' base pairing in either the plus- or minus-strand. In infection experiments, transcripts with mutations which disrupted the Box II-II' interaction in the plus-strand structure replicated less efficiently than mutants in which the Box II-II' interaction was disrupted in the minus-strand. These findings indicate that the complex 5'-proximal plus-strand structure to which the Box II-II' interaction contributes comprises at least part of the promoter for plus-strand RNA synthesis. Images PMID:8464729

  19. 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.

  20. 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

  1. STREAK damping. Technical report

    SciTech Connect

    Baker, J.; Peyton, S.; Freiberg, H.

    1989-12-01

    This report documents a study aimed at improving the damping in STREAK. A form and value for an artificial viscosity is recommended which appears to control ringing and overshoots without overdamping.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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).

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Devil-Streaked Plain

    NASA Technical Reports Server (NTRS)

    2006-01-01

    19 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark streaks on a plain south of the giant impact basin, Hellas Planitia. The streaks map the routes traveled by dozens of individual southern spring and early summer dust devils.

    Location near: 68.4oS, 296.1oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  14. 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.

  15. 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

  16. 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

  17. Varicose Veins

    MedlinePlus

    Varicose veins are swollen, twisted veins that you can see just under the skin. They usually occur in ... of the body. Hemorrhoids are a type of varicose vein. Your veins have one-way valves that help ...

  18. 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.

  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. 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

  1. 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

  2. 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...

  3. 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…

  4. 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.

  5. 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

  6. Varicose Veins

    MedlinePlus

    ... page from the NHLBI on Twitter. What Are Varicose Veins? Español Varicose (VAR-i-kos) veins are swollen, ... can form in other parts of the body. Varicose veins are a common condition. They usually cause few ...

  7. Comparison of Streak Tube Performance

    SciTech Connect

    Lerche, R A; Andrews, D S; Bell, P M; Griffiths, R L; Huey, A W; McDonald, J W; de Dios, G V

    2004-11-04

    The performance of four streak tubes in six streak camera configurations is reported. Evaluations were made as part of a search for a streak tube to replace the obsolete RCA C73435 used in the ICF Program's optical streak cameras. Characteristics measured include linearity, spatial and temporal resolution, line-spread function, contrast transfer ratio (CTR), and dynamic range. Tubes evaluated are the RCA C73435, Photonis P510, Photek ST-Y, and Hamamatsu N8059. The RCA C73435 was evaluated in three camera configurations: large format CCD coupled directly to the streak tube, CCD directly coupled to an image intensifier tube (IIT), and the original configuration with a smaller CCD lens coupled to the IIT output. The Photonis and Photek tubes were characterized in configurations where they were directly coupled to large format CCDs. Optimum spatial resolution is achieved when the IIT is removed. Maximum dynamic range requires a configuration where a single photoelectron from the photocathode produces a signal that is {approx}5 times the CCD read noise. The Photonis P510 tube with the E2V CCD forms a well-optimized streak camera system.

  8. Characterization of Dark Streaks on Martian Slopes

    NASA Astrophysics Data System (ADS)

    Fenton, L. K.; Danielson, G. E.; Albee, A.; MGS MOC Science Team

    1998-09-01

    The narrow angle MOC images from the Mars Global Surveyor (MGS) show dozens of examples of dark streaks on Martian hillsides that may be indicative of fluid flow. In many cases multiple streaks seem to initiate from a narrow layer near the tops of steep slopes. They appear from these layers as narrow features that quickly broaden and then either remain the same width downhill or narrow and disappear. The largest streak observed to date is approximately 2 km in length and 100 m in width. MOLA data is not yet available to determine the slope down the length of the streaks. The lack of variation in brightness downhill and across the streaks shows that the formation of each streak occurred quickly. The streaks are widely distributed globally, but seem to be confined to layered materials. The streaks' characteristics show not only that the material forming them moved rapidly downslope but also that the streak material originated within the nearby bedrock. Change in brightness from one streak to another provides relative streak ages, assuming that dust infall causes an increase in streak albedo. The dark streaks are caused by a process that appears similar to fluid flow at the resolution of the MOC images. Possible causes of the streaks are water flow, lava flow, and debris flow. Our results are not yet conclusive as to the origins of the dark streaks, but we narrow the range of possible formation processes.

  9. Angioid streaks - a rare cause of neovascular glaucoma. Case report.

    PubMed

    Ungureanu, E; Geamanu, A; Careba, I; Grecescu, M; Gradinaru, S

    2014-01-01

    Rationale. Neovascular glaucoma is the type of glaucoma most refractory to treatment. The most frequent causes are those associated with retinal hypoxia, such as proliferative diabetic retinopathy, central retinal vein occlusion, branch retinal vein occlusion, central retinal arterial occlusion, ischemic ocular syndrome etc. Rare causes of neovascular glaucoma are multiple and are due to VEGF synthesis associated with chorioretinal inflammations or degenerations. We present a case with neovascular glaucoma associated with an extremely rare cause, angioid streaks Objective. The objective of our prsentation was to asses efficacy of the 5-FU associated trabeculectomy following bevacizumab intravitreal administration Methods and results. Case report of a 48 years old female patient which presented at the emergency room with painful red left eye. At presentation best corrected left eye visual acuity was 1/10, intraocular pressure was 36 mm Hg. Examination established the diagnosis of Neovascular glaucoma associated with angioid streaks. After intravenous Manitol, oral Acetazolamide and topical treatment with fixed combination timolol-brinzolamide, topical steroid and mydriatic intraocular pressure decreased. Intravitreal bevacizumab injection was performed, followed after 3 weeks by trabeculectomy. Discussion. Angioid streaks are an extremely rare cause of neovascular glaucoma. The treatment is similar to the treatment for other causes of neovascular glaucoma. PMID:27057253

  10. Angioid streaks - a rare cause of neovascular glaucoma. Case report.

    PubMed Central

    Ungureanu, E; Geamanu, A; Careba, I; Grecescu, M; Gradinaru, S

    2014-01-01

    Rationale. Neovascular glaucoma is the type of glaucoma most refractory to treatment. The most frequent causes are those associated with retinal hypoxia, such as proliferative diabetic retinopathy, central retinal vein occlusion, branch retinal vein occlusion, central retinal arterial occlusion, ischemic ocular syndrome etc. Rare causes of neovascular glaucoma are multiple and are due to VEGF synthesis associated with chorioretinal inflammations or degenerations. We present a case with neovascular glaucoma associated with an extremely rare cause, angioid streaks Objective. The objective of our prsentation was to asses efficacy of the 5-FU associated trabeculectomy following bevacizumab intravitreal administration Methods and results. Case report of a 48 years old female patient which presented at the emergency room with painful red left eye. At presentation best corrected left eye visual acuity was 1/10, intraocular pressure was 36 mm Hg. Examination established the diagnosis of Neovascular glaucoma associated with angioid streaks. After intravenous Manitol, oral Acetazolamide and topical treatment with fixed combination timolol-brinzolamide, topical steroid and mydriatic intraocular pressure decreased. Intravitreal bevacizumab injection was performed, followed after 3 weeks by trabeculectomy. Discussion. Angioid streaks are an extremely rare cause of neovascular glaucoma. The treatment is similar to the treatment for other causes of neovascular glaucoma PMID:27057253

  11. 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.

  12. The Rochester Optical Streak System

    NASA Astrophysics Data System (ADS)

    Jaanimagi, P. A.; Boni, R.; Keck, R. L.; Donaldson, W. R.; Meyerhofer, D. D.

    2004-11-01

    A modern, self-calibrating, remotely controlled streak camera platform capable of accepting a variety of different streak tubes has been developed. Our current systems include P510, P820, and PJX streak tubes with both S-1 and S-20 photocathodes. The input may be either fiber delivery or free-space propagation and is relayed to the photocathode with an achromatic Offner triplet. Calibration functions include autofocus of the input and electron optics, geometric distortion and flat-field correction, system gain, and linearity. The four remotely selectable sweep speeds are calibrated with an on-board optical comb generator. The recording system is a fiber-coupled back-illuminated CCD camera. We will present data illustrating the many features of the ROSS camera as applied to laser and plasma diagnostics. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-92SF19460.

  13. Focus on Varicose Veins

    MedlinePlus

    ... Other veins often mistaken for varicose veins are spider veins and reticular veins, which are the visible ... greenish-blue veins that appear in our legs. Spider veins or teleangiectesias are tiny veins that you ...

  14. 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.

  15. 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

  16. 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

  17. Dark streaks on talus slopes, Mars

    NASA Astrophysics Data System (ADS)

    Ferguson, H. M.; Lucchitta, B. K.

    1984-04-01

    High-resolution pictures of talus slopes on Mars show small, dark streaks that characteristically widen downward. These streaks are different from the thin and even streaks of various albedos that stream from cliffs on talus slopes, but gradations between the two streak types occur and not all streaks can be classified with confidence. In order to study the nature and origin of the small, widening, dark streaks, all Viking pictures with a resolution of less than 100 m/pixel were surveyed. To date several hundred streaks were located, but only few are of high enough resolution to be confidently identified as widening downwards. The approximate dimensions of the streaks were measured and their shapes, numbers, position, and spacing on slopes were noted. They were plotted on a topographic map, and their relation to topography, geologic units, and regions of distinct thermal inertia and albedo were studied. Also noted was the season at which images containing streaks were acquired and the direction of illumination. Albedo measurements are in progress. Several streaks can be seen stereoscopically, but none are observed on color images. The observation of small dark streaks on talus slopes on Mars is compatible with an interpretation of their origin as eruptions of small masses of wet debris in places where steep walls intersect aquifers or where seasonal equatorial warming permits the local melting of ground ice.

  18. What Causes Varicose Veins?

    MedlinePlus

    ... page from the NHLBI on Twitter. What Causes Varicose Veins? Weak or damaged valves in the veins can ... space. These are varicose veins. Normal Vein and Varicose Vein Figure A shows a normal vein with a ...

  19. Yellow Fever

    MedlinePlus

    ... tropical and subtropical areas in South America and Africa. The virus is transmitted to people by the ... fever Maps of Yellow fever endemic areas in Africa and South America Yellow fever vaccination Prevention Vaccine ...

  20. A novel emaravirus is associated with redbud yellow ringspot disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow ringspot is the only virus-like disease reported in redbud (Cercis spp.) with symptoms including vein clearing, chlorotic ringspots and oak-leaf pattern. A putative new emaravirus was present in 48 of 48l trees displaying typical yellow ringspot symptoms and the name redbud yellow ringspot as...

  1. 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.

  2. 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...

  3. Vein Problems Related to Varicose Veins

    MedlinePlus

    ... your doctor if you think you have them. Spider Veins Spider veins are a smaller version of varicose veins and a less serious type of telangiectasias. Spider veins involve the capillaries, the smallest blood vessels ...

  4. Black streak root rot of lentil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Black streak root rot of lentil is caused by the soil borne fungus Thielaviopsis basicola. The pathogen is widespread. The disease shows symptoms of black streaking on root, and stunted plants. The disease is favored by cool and moist weather. Management of the disease rely on avoiding fields wi...

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. Varicose vein - noninvasive treatment

    MedlinePlus

    Sclerotherapy; Laser therapy - varicose veins; Radiofrequency vein ablation; Endovenous thermal ablation; Ambulatory phlebectomy; Transilluminated power phlebotomy; Endovenous laser ablation; Varicose vein ...

  10. 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.

  11. Varicose vein stripping

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002952.htm Varicose vein stripping To use the sharing features on this ... enable JavaScript. Vein stripping is surgery to remove varicose veins in the legs. Description Varicose veins are swollen, ...

  12. Varicose vein - noninvasive treatment

    MedlinePlus

    Sclerotherapy; Laser therapy - varicose veins; Radiofrequency vein ablation; Endovenous thermal ablation; Ambulatory phlebectomy; Transilluminated power phlebotomy; Endovenous laser ablation; Varicose ...

  13. Compact Optical Technique for Streak Camera Calibration

    SciTech Connect

    Curt Allen; Terence Davies; Frans Janson; Ronald Justin; Bruce Marshall; Oliver Sweningsen; Perry Bell; Roger Griffith; Karla Hagans; Richard Lerche

    2004-04-01

    The National Ignition Facility is under construction at the Lawrence Livermore National Laboratory for the U.S. Department of Energy Stockpile Stewardship Program. Optical streak cameras are an integral part of the experimental diagnostics instrumentation. To accurately reduce data from the streak cameras a temporal calibration is required. This article describes a technique for generating trains of precisely timed short-duration optical pulses that are suitable for temporal calibrations.

  14. 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.

  15. Yellow Fever Vaccine

    MedlinePlus

    What is yellow fever?Yellow fever is a serious disease caused by the yellow fever virus. It is found in certain parts of Africa and South America. Yellow fever is spread through the bite of an infected ...

  16. Update on the Rochester Optical Streak System

    NASA Astrophysics Data System (ADS)

    Jaanimagi, P. A.

    2005-10-01

    The Rochester Optical Streak System (ROSS) is a modern, self-calibrating, remotely controlled streak camera platform capable of accepting a variety of different streak tubes. The optical calibration module (OCM) for the ROSS camera has been completed and integrated with the main streak tube housing. The OCM incorporates an achromatic Offner triplet that allows fiber-delivered input and free-space propagated signals to be simultaneously relayed to the photocathode. It also encloses of the light sources and reticles required to accomplish a full suite of system calibrations including: autofocus of the input and electron optics, geometric distortion and flat-field correction, time base, system gain, and linearity. We will present data illustrating the system capabilities and our latest results comparing the dynamic performance of the P510 and P820 streak tubes. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-92SF19460.

  17. Deep Vein Thrombosis

    MedlinePlus

    MENU Return to Web version Deep Vein Thrombosis Overview What is deep vein thrombosis? Deep vein thrombosis (also called DVT) is a blood clot in a vein deep inside your body. These clots usually occur in your leg veins. While DVT is a fairly common condition, it is ...

  18. 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 ... vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem ...

  19. 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 ...

  20. Yellow Fever Vaccine

    MedlinePlus

    What is yellow fever?Yellow fever is a serious disease caused by the yellow fever virus. It is found in certain parts of Africa ... How can I prevent yellow fever?Yellow fever vaccine can prevent yellow fever. ... only at designated vaccination centers. After getting the vaccine, you ...

  1. 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

  2. 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.

  3. ASTRiDE: Automated Streak Detection for Astronomical Images

    NASA Astrophysics Data System (ADS)

    Kim, Dae-Won

    2016-05-01

    ASTRiDE detects streaks in astronomical images using a "border" of each object (i.e. "boundary-tracing" or "contour-tracing") and their morphological parameters. Fast moving objects such as meteors, satellites, near-Earth objects (NEOs), or even cosmic rays can leave streak-like traces in the images; ASTRiDE can detect not only long streaks but also relatively short or curved streaks.

  4. 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.

  5. 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…

  6. 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.

  7. Bichromatic particle streak velocimetry bPSV

    NASA Astrophysics Data System (ADS)

    Voss, Björn; Stapf, Julian; Berthe, André; Garbe, Christoph S.

    2012-11-01

    We propose a novel technique for three-dimensional three-component (3D3C) interfacial flow measurement. It is based on the particle streak velocimetry principle. A relatively long integration time of the camera is used for capturing the movement of tracer particles as streaks on the sensor. The velocity along these streaks is extracted by periodically changing the illumination using a known pattern. A dye with different absorption characteristics in two distinct wavelengths is used to color the fluid. The depth of particles relative to the fluid interface can then be computed from their intensities when illuminated with light sources at those two different wavelengths. Hence, from our approach, a bichromatic, periodical illumination together with an image processing routine for precisely extracting particle streak features is used for measuring 3D3C fluid flow with a single camera. The technique is applied to measuring turbulent Rayleigh-Bénard convection at the free air--water interface. Using Lagrangian statistics, we are able to demonstrate a clear transition from the Batchelor regime to the Richardson regime, both of which were postulated for isotropic turbulence. The relative error of the velocity extraction of our new technique was found to be below 0.5 %.

  8. 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.

  9. Photonic streaking of attosecond pulse trains

    NASA Astrophysics Data System (ADS)

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

  10. 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.

  11. Particle Streak Velocimetry of Supersonic Nozzle Flows

    NASA Technical Reports Server (NTRS)

    Willits, J. D.; Pourpoint, T. L.

    2016-01-01

    A novel velocimetry technique to probe the exhaust flow of a laboratory scale combustor is being developed. The technique combines the advantages of standard particle velocimetry techniques and the ultra-fast imaging capabilities of a streak camera to probe high speed flows near continuously with improved spatial and velocity resolution. This "Particle Streak Velocimetry" technique tracks laser illuminated seed particles at up to 236 picosecond temporal resolution allowing time-resolved measurement of one-dimensional flows exceeding 2000 m/s as are found in rocket nozzles and many other applications. Developmental tests with cold nitrogen have been performed to validate and troubleshoot the technique with supersonic flows of much lower velocity and without background noise due to combusting flow. Flow velocities on the order of 500 m/s have been probed with titanium dioxide particles and a continuous-wave laser diode. Single frame images containing multiple streaks are analyzed to find the average slope of all incident particles corresponding to the centerline axial flow velocity. Long term objectives for these tests are correlation of specific impulse to theoretical combustion predictions and direct comparisons between candidate green fuels and the industry standard, monomethylhydrazine, each tested under identical conditions.

  12. Portal Vein Thrombosis

    PubMed Central

    Mallet, Thierry; 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

  13. Preventing Deep Vein Thrombosis

    MedlinePlus

    ... Patient Education FAQs Preventing Deep Vein Thrombosis Patient Education Pamphlets - Spanish Preventing Deep Vein Thrombosis FAQ174, August 2011 PDF ... Your Practice Patient Safety & Quality Payment Reform (MACRA) Education & Events Annual ... Pamphlets Teen Health About ACOG About Us Leadership & ...

  14. Deep Vein Thrombosis

    MedlinePlus

    ... page from the NHLBI on Twitter. What Is Deep Vein Thrombosis? Español 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 ...

  15. Varicose veins and venous insufficiency

    MedlinePlus

    Varicose veins are swollen, twisted, and enlarged veins that you can see under the skin. They are often ... from the blood that collects there, which causes varicose veins. Smaller varicose veins that you can see on ...

  16. Signal averaging x-ray streak camera with picosecond jitter

    NASA Astrophysics Data System (ADS)

    Maksimchuk, A.; Kim, M.; Workman, J.; Korn, G.; Squier, J.; Du, D.; Umstadter, D.; Mourou, G.; Bouvier, M.

    1996-03-01

    We have developed an averaging picosecond x-ray streak camera using a dc-biased photoconductive switch as a generator of a high-voltage ramp. The streak camera is operated at a sweep speed of up to 8 ps/mm, shot-to-shot jitter is less than ±1 ps. The streak camera has been used to measure the time history of broadband x-ray emission from an ultrashort pulse laser-produced plasma. Accumulation of the streaked x-ray signals significantly improved the signal-to-noise ratio of the data obtained.

  17. 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

  18. 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.

  19. Branch retinal vein occlusion.

    PubMed

    Hamid, Sadaf; Mirza, Sajid Ali; Shokh, Ishrat

    2008-01-01

    Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) are the two basic types of vein occlusion. Branch retinal vein occlusion is three times more common than central retinal vein occlusion and- second only to diabetic retinopathy as the most common retinal vascular cause of visual loss. The origin of branch retinal vein occlusion undoubtedly includes both systemic factors such as hypertension and local anatomic factors such as arteriovenous crossings. Branch retinal vein occlusion causes a painless decrease in vision, resulting in misty or distorted vision. Current treatment options don't address the underlying aetiology of branch retinal vein occlusion. Instead they focus on treating sequelae of the occluded venous branch, such as macular oedema, vitreous haemorrhage and traction retinal detachment from neovascularization. Evidences suggest that the pathogenesis of various types of retinal vein occlusion, like many other ocular vascular occlusive disorders, is a multifactorial process and there is no single magic bullet that causes retinal vein occlusion. A comprehensive management of patients with retinal vascular occlusions is necessary to correct associated diseases or predisposing abnormalities that could lead to local recurrences or systemic event. Along with a review of the literature, a practical approach for the management of retinal vascular occlusions is required, which requires collaboration between the ophthalmologist and other physicians: general practitioner, cardiologist, internist etc. as appropriate according to each case. PMID:19385476

  20. 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

  1. SDOSS: A spatially discriminating, optical streaked spectrograph

    SciTech Connect

    Cobble, J.; Evans, S.; Fernandez, J.; Oertel, J.; Watt, R.; Wilde, B.

    1995-05-01

    SDOSS is employed to study broadband laser scattering encompassing SBS, SRS, and the 3/2-{omega} signature of two plasmon decay for ns-scale laser-plasma experiments with 351 or 527-nm drive. It uses a Cassegrain telescope to image scattered light from a laser plasma onto a field stop. The telescope magnification and the stop aperture provide spatial discrimination of target plane scatter. A UV lens relays the image to a 0.25-m spectrograph which is lens coupled to a streak camera with an S-1 photocathode. The streak output is imaged onto a CCD camera. In its 512 x 480 pixel array, the CCD covers a spectral range from 200 to 800 nm with 4-nm resolution and can be adjusted to look from 350 to 1,060 nm. The sweep speed is variable with full window values of 30, 12, 6 ns, and faster. An optical fiducial provides a spectral and temporal marker. On the Livermore Nova laser, SDOSS has been used to determine spatial density in gas-filled hohlraums from SRS signals. At Trident in Los Alamos, it has been employed for similar measurements with long scale length plasmas in SBS and SRS seeding experiments. It has proven to be a versatile tool for studying the physics of laser-generated plasmas.

  2. Varicose Veins and Other Vein Disorders

    MedlinePlus

    ... Share Glossary Basic Facts & Information Causes & Symptoms Diagnosis & Tests Care & Treatment Lifestyle & Management Other Resources Caregiving How To's Related Topics Peripheral Artery Disease Join our e-newsletter! Aging & Health A to Z Varicose Veins and Other ...

  3. Radar-visible wind streaks in the Altiplano of Bolivia

    NASA Technical Reports Server (NTRS)

    Greeley, R.; Christensen, P.

    1984-01-01

    Isolated knobs that are erosional remnants of central volcanoes or of folded rocks occur in several areas of the Altiplano are visible on both optical and images. The optically visible streaks occur in the immediate lee of the knobs, whereas the radar visible streaks occur in the zone downwind between the knobs. Aerial reconnaissance and field studies showed that the optically visible streaks consist of a series of small ( 100 m wide) barchan and barchanoid dunes, intradune sand sheets, and sand hummocks (large shrub coppice dunes) up to 15 m across and 5 m high. On LANDSAT images these features are poorly resolved but combine to form a bright streak. On the radar image, this area also appears brighter than the zone of the radar dark streak; evidently, the dunes and hummocks serve as radar reflectors. The radar dark streak consists of a relatively flat, smooth sand sheet which lacks organized aerolian bedforms, other than occasional ripples. Wind velocity profiles show a greater U value in the optically bright streak zone than in the radar dark streak.

  4. Inducible Resistance to Maize Streak Virus

    PubMed Central

    Shepherd, Dionne N.; Dugdale, Benjamin; Martin, Darren P.; Varsani, Arvind; Lakay, Francisco M.; Bezuidenhout, Marion E.; Monjane, Adérito L.; Thomson, Jennifer A.; Dale, James; Rybicki, Edward P.

    2014-01-01

    Maize streak virus (MSV), which causes maize streak disease (MSD), is the major viral pathogenic constraint on maize production in Africa. Type member of the Mastrevirus genus in the family Geminiviridae, MSV has a 2.7 kb, single-stranded circular DNA genome encoding a coat protein, movement protein, and the two replication-associated proteins Rep and RepA. While we have previously developed MSV-resistant transgenic maize lines constitutively expressing “dominant negative mutant” versions of the MSV Rep, the only transgenes we could use were those that caused no developmental defects during the regeneration of plants in tissue culture. A better transgene expression system would be an inducible one, where resistance-conferring transgenes are expressed only in MSV-infected cells. However, most known inducible transgene expression systems are hampered by background or “leaky” expression in the absence of the inducer. Here we describe an adaptation of the recently developed INPACT system to express MSV-derived resistance genes in cell culture. Split gene cassette constructs (SGCs) were developed containing three different transgenes in combination with three different promoter sequences. In each SGC, the transgene was split such that it would be translatable only in the presence of an infecting MSV’s replication associated protein. We used a quantitative real-time PCR assay to show that one of these SGCs (pSPLITrepIII-Rb-Ubi) inducibly inhibits MSV replication as efficiently as does a constitutively expressed transgene that has previously proven effective in protecting transgenic maize from MSV. In addition, in our cell-culture based assay pSPLITrepIII-Rb-Ubi inhibited replication of diverse MSV strains, and even, albeit to a lesser extent, of a different mastrevirus species. The application of this new technology to MSV resistance in maize could allow a better, more acceptable product. PMID:25166274

  5. 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

  6. Streak interactions and breakdown in boundary layer flows

    NASA Astrophysics Data System (ADS)

    Brandt, Luca; de Lange, H. C.

    2008-02-01

    The objective of this paper is to show that the interaction of streamwise velocity streaks of finite length can lead to turbulent breakdown in the flat-plate boundary layer flow. The work is motivated by previous numerical and experimental studies of transitional flows where the high-frequency oscillations leading to turbulence are seen to form in the region of strongest shear induced by streaks in relative motion. Therefore, a model for the interaction of steady and unsteady (i.e., slowly moving in the spanwise direction) spanwise periodic streaks is proposed. The interaction of two subsequent streaks is investigated for varying collision parameters. In particular, the relative spanwise position and angle are considered. The results show that the interaction is able to produce both a symmetric and asymmetric breakdown without the need for additional random noise from the main stream. Velocity structures characteristic of both scenarios are analyzed. Hairpin and Λ vortices are found in the case of symmetric collision between a low-speed region and an incoming high-speed streak, when a region of strong wall-normal shear is induced. Alternatively, when the incoming high-momentum fluid is misaligned with the low-speed streak in front, single quasi-streamwise vortices are identified. Despite the different symmetry at the breakdown, the detrimental interaction involves for both cases the tail of a low-speed region and the head of a high-speed streak. Further, the breakdown appears in both scenarios as an instability of three-dimensional shear layers formed between the two streaks. The streak interaction scenario is suggested to be of relevance for turbulence production in wall-bounded flows.

  7. 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.

  8. 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

  9. Varicose veins and venous insufficiency

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/001109.htm Varicose veins and venous insufficiency To use the sharing features on this page, please enable JavaScript. Varicose veins are swollen, twisted, and enlarged veins that you ...

  10. 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.

  11. Temporal Contrast Changes in Dark Slope Streaks on Mars

    NASA Astrophysics Data System (ADS)

    Chilton, Heather; Phillips, C. B.; Brown, A.; Fenton, L.

    2013-01-01

    Dark slope streaks on Mars are among 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 streaks have the highest contrast suggesting they fade over time. One theory for this is atmospheric dust fallout slowly raising the albedo of the surface exposed by the dust avalanche, progressively increasing streak albedo 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]. CRISM images were identified for spatial overlap and temporal range, then further selected for image sets with well-matched viewing geometries. The 1 micron wavelength band was used to reduce atmospheric interference and brightness values then collected at multiple locations within and alongside individual streaks, with on-streak/off-streak pairs at points of similar elevation. Values were then divided by the cosine of the corresponding MOLA incidence angle for brightness variation correction due to topography. Measurements for overlapping images established local and overall averages for the rate of change in contrast ratio. Results showed a range of trends including streaks that darkened, brightened, 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

  12. Semiclassical model for attosecond angular streaking.

    PubMed

    Smolarski, M; Eckle, P; Keller, U; Dörner, R

    2010-08-16

    Attosecond angular streaking is a new technique to achieve unsurpassed time accuracy of only a few attoseconds. Recently this has been successfully used to set an upper limit on the electron tunneling delay time in strong laser field ionization. The measurement technique can be modeled with either the time-dependent Schrödinger equation (TDSE) or a more simple semiclassical approach that describes the process in two steps in analogy to the three-step model in high harmonic generation (HHG): step one is the tunnel ionization and step two is the classical motion in the strong laser field. Here we describe in detail a semiclassical model which is based on the ADK theory for the tunneling step, with subsequent classical propagation of the electron in the laser field. We take into account different ellipticities of the laser field and a possible wavelength-dependent ellipticity that is typically observed for pulses in the two-optical-cycle regime. This semiclassical model shows excellent agreement with the experimental result. PMID:20721150

  13. Simulation of FEL pulse length calculation with THz streaking method.

    PubMed

    Gorgisyan, I; Ischebeck, R; Prat, E; Reiche, S; Rivkin, L; Juranić, P

    2016-05-01

    Having accurate and comprehensive photon diagnostics for the X-ray pulses delivered by free-electron laser (FEL) facilities is of utmost importance. Along with various parameters of the photon beam (such as photon energy, beam intensity, etc.), the pulse length measurements are particularly useful both for the machine operators to measure the beam parameters and monitor the stability of the machine performance, and for the users carrying out pump-probe experiments at such facilities to better understand their measurement results. One of the most promising pulse length measurement techniques used for photon diagnostics is the THz streak camera which is capable of simultaneously measuring the lengths of the photon pulses and their arrival times with respect to the pump laser. This work presents simulations of a THz streak camera performance. The simulation procedure utilizes FEL pulses with two different photon energies in hard and soft X-ray regions, respectively. It recreates the energy spectra of the photoelectrons produced by the photon pulses and streaks them by a single-cycle THz pulse. Following the pulse-retrieval procedure of the THz streak camera, the lengths were calculated from the streaked spectra. To validate the pulse length calculation procedure, the precision and the accuracy of the method were estimated for streaking configuration corresponding to previously performed experiments. The obtained results show that for the discussed setup the method is capable of measuring FEL pulses with about a femtosecond accuracy and precision. PMID:27140142

  14. Simulation of FEL pulse length calculation with THz streaking method

    PubMed Central

    Gorgisyan, I.; Ischebeck, R.; Prat, E.; Reiche, S.; Rivkin, L.; Juranić, P.

    2016-01-01

    Having accurate and comprehensive photon diagnostics for the X-ray pulses delivered by free-electron laser (FEL) facilities is of utmost importance. Along with various parameters of the photon beam (such as photon energy, beam intensity, etc.), the pulse length measurements are particularly useful both for the machine operators to measure the beam parameters and monitor the stability of the machine performance, and for the users carrying out pump–probe experiments at such facilities to better understand their measurement results. One of the most promising pulse length measurement techniques used for photon diagnostics is the THz streak camera which is capable of simultaneously measuring the lengths of the photon pulses and their arrival times with respect to the pump laser. This work presents simulations of a THz streak camera performance. The simulation procedure utilizes FEL pulses with two different photon energies in hard and soft X-ray regions, respectively. It recreates the energy spectra of the photoelectrons produced by the photon pulses and streaks them by a single-cycle THz pulse. Following the pulse-retrieval procedure of the THz streak camera, the lengths were calculated from the streaked spectra. To validate the pulse length calculation procedure, the precision and the accuracy of the method were estimated for streaking configuration corresponding to previously performed experiments. The obtained results show that for the discussed setup the method is capable of measuring FEL pulses with about a femtosecond accuracy and precision. PMID:27140142

  15. 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

  16. Retinal vein occlusion

    MedlinePlus

    ... Berrocal MH, Rodriguez FJ, et al. Pan-American Collaborative Retina Study Group (PACORES). Comparison of two doses ... retinal vein occlusion: results from the Pan-American Collaborative Retina Study Group at 6 months of follow- ...

  17. 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

  18. Popliteal vein aneurysm.

    PubMed

    Falkowski, A; Poncyljusz, W; Zawierucha, D; Kuczmik, W

    2006-06-01

    The incidence of a popliteal vein aneurysm is extremely low. Two cases of this rare venous anomaly are described. The epidemiology, morphology, and diagnostic methods are discussed and the potentially dangerous complications and treatment methods are presented. PMID:16796307

  19. 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

  20. 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...

  1. 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 batter’s 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

  2. 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.

  3. The Dellistrique 2S - A 200 Channel Streak Camera

    NASA Astrophysics Data System (ADS)

    Majumdar, S.

    1985-02-01

    Despite a great deal of effort to improve time resolution of streak cameras, the best reported time resolution remained just under one picosecond for more than a decade. However, the sensitivity and resolution of these devices have improved substantially over this time. In this paper the design of a very high performance streak camera, capable of resolving one picosecond on 200 parallel channels with single photo-electron detection capability: the Dellistrique 2S. The system comprises of a streak tube type Picotron 200 with a photocathode resolving 200 spatial channels along a slit and with an extraction field near the photocathode of greater than 16 KV per cm and with a non saturating phosphor screen as the main component. There is post streak tube intensification of 30,000 at the streak tube output wavelength which increases both the sensitivity of the system. The intensifier is coupled to a CCD readout device fibre-optically for producing a two dimensional image with a dynamic range of greater than 500. The camera can be operated at a repetition rate of between 80 MHz and 240 MHz using R.F. scanning methods. Upto 20 parallel channels have been tried with parallel information recording, which is well below the tube's capability of recording 200 independent channels. The image is virtually distortion free across the whole usable screen length of 45 mm for a large screen tube.

  4. 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.

  5. 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

  6. Acquired Jugular Vein Aneurysm

    PubMed Central

    Hopsu, Erkki; Tarkkanen, Jussi; Vento, Seija I.; Pitkäranta, Anne

    2009-01-01

    Venous malformations of the jugular veins are rare findings. Aneurysms and phlebectasias are the lesions most often reported. We report on an adult patient with an abruptly appearing large tumorous mass on the left side of the neck identified as a jugular vein aneurysm. Upon clinical examination with ultrasound, a lateral neck cyst was primarily suspected. Surgery revealed a saccular aneurysm in intimate connection with the internal jugular vein. Histology showed an organized hematoma inside the aneurysmal sac, which had a focally thinned muscular layer. The terminology and the treatment guidelines of venous dilatation lesions are discussed. For phlebectasias, conservative treatment is usually recommended, whereas for saccular aneurysms, surgical resection is the treatment of choice. While an exact classification based on etiology and pathophysiology is not possible, a more uniform taxonomy would clarify the guidelines for different therapeutic modalities for venous dilatation lesions. PMID:20107571

  7. A time-resolved image sensor for tubeless streak cameras

    NASA Astrophysics Data System (ADS)

    Yasutomi, Keita; Han, SangMan; Seo, Min-Woong; Takasawa, Taishi; Kagawa, Keiichiro; Kawahito, Shoji

    2014-03-01

    This paper presents a time-resolved CMOS image sensor with draining-only modulation (DOM) pixels for tube-less streak cameras. Although the conventional streak camera has high time resolution, the device requires high voltage and bulky system due to the structure with a vacuum tube. The proposed time-resolved imager with a simple optics realize a streak camera without any vacuum tubes. The proposed image sensor has DOM pixels, a delay-based pulse generator, and a readout circuitry. The delay-based pulse generator in combination with an in-pixel logic allows us to create and to provide a short gating clock to the pixel array. A prototype time-resolved CMOS image sensor with the proposed pixel is designed and implemented using 0.11um CMOS image sensor technology. The image array has 30(Vertical) x 128(Memory length) pixels with the pixel pitch of 22.4um. .

  8. Attosecond streaking in a nano-plasmonic field

    NASA Astrophysics Data System (ADS)

    Kelkensberg, F.; Koenderink, A. F.; Vrakking, M. J. J.

    2012-09-01

    A theoretical study of the application of attosecond streaking spectroscopy to time-resolved studies of the plasmonic fields surrounding isolated, resonantly excited spherical nanoparticles is presented. A classification of the different regimes in attosecond streaking is proposed and identified in our results that are derived from Mie calculations of plasmon fields, coupled to classical electron trajectory simulations. It is shown that in an attosecond streaking experiment, the electrons are almost exclusively sensitive to the component of the field parallel to the direction in which they are detected. This allows one to probe the different components of the field individually by resolving the angle of emission of the electrons. Finally, simulations based on fields calculated by finite-difference time-domain (FDTD) are compared with the results obtained using Mie fields. The two are found to be in good agreement with each other, supporting the notion that FDTD methods can be used to reliably investigate non-spherical structures.

  9. Mead Crater, Venus - Aerodynamic roughness of wind streaks

    NASA Astrophysics Data System (ADS)

    Williams, K. K.; Greeley, R.

    1997-03-01

    Radar backscatter images of Venus returned by the Magellan spacecraft revealed many aeolian features on the planet's surface. While much work has focused on terrestrial wind streaks, the harsh environment of Venus limits direct measurement of surface properties, such as aerodynamic roughness, that affect aeolian features on that planet. However, a correlation between radar backscatter and aerodynamic roughness (Z0) for the S-band radar system on Magellan can be used to study the aerodynamic roughnesses of areas in which Venusian wind streaks occur. The aerodynamic roughness of areas with both radar-bright and radar-dark wind streaks near Mead crater are calculated and compared to z0 values measured on Earth in order to compare the surface of Venus with known terrestrial surface textures.

  10. Streak Camera Performance with Large-Format CCD Readout

    SciTech Connect

    Lerche, R A; Andrews, D S; Bell, P M; Griffith, R L; McDonald, J W; Torres, P III; Vergel de Dios, G

    2003-07-08

    The ICF program at Livermore has a large inventory of optical streak cameras that were built in the 1970s and 1980s. The cameras include micro-channel plate image-intensifier tubes (IIT) that provide signal amplification and early lens-coupled CCD readouts. Today, these cameras are still very functional, but some replacement parts such as the original streak tube, CCD, and IIT are scarce and obsolete. This article describes recent efforts to improve the performance of these cameras using today's advanced CCD readout technologies. Very sensitive, large-format CCD arrays with efficient fiber-optic input faceplates are now available for direct coupling with the streak tube. Measurements of camera performance characteristics including linearity, spatial and temporal resolution, line-spread function, contrast transfer ratio (CTR), and dynamic range have been made for several different camera configurations: CCD coupled directly to the streak tube, CCD directly coupled to the IIT, and the original configuration with a smaller CCD lens coupled to the IIT output. Spatial resolution (limiting visual) with and without the IIT is 8 and 20 lp/mm, respectively, for photocathode current density up to 25% of the Child-Langmuir (C-L) space-charge limit. Temporal resolution (fwhm) deteriorates by about 20% when the cathode current density reaches 10% of the C-L space charge limit. Streak tube operation with large average tube current was observed by illuminating the entire slit region through a Ronchi ruling and measuring the CTR. Sensitivity (CCD electrons per streak tube photoelectron) for the various configurations ranged from 7.5 to 2,700 with read noise of 7.5 to 10.5 electrons. Optimum spatial resolution is achieved when the IIT is removed. Maximum dynamic range requires a configuration where a single photoelectron from the photocathode produces a signal that is 3 to 5 times the read noise.

  11. Varicose vein surgery.

    PubMed

    Kendler, Micheal; Fellmer, Peter T; Wetzig, Tino

    2012-03-01

    Venous diseases are common in the general population. After a comprehensive diagnostic evaluation, an individual therapeutic approach should be selected on the basis of the findings, with the aim of treating the diseased vein segments and improving quality of life. Numerous therapeutic options are available for the treatment of varicose veins. In addition to conservative methods such as compression therapy, exercise or drugs, surgical procedures such as traditional surgery, thermal ablation techniques or sclerotherapy can be performed. Recent developments include the use of endoluminal water vapor or mechano-chemical endovenous ablation. PMID:22222053

  12. 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.

  13. Portal vein thrombosis.

    PubMed

    Chawla, Yogesh K; Bodh, Vijay

    2015-03-01

    Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion. PMID:25941431

  14. Portal Vein Thrombosis

    PubMed Central

    Chawla, Yogesh K.; Bodh, Vijay

    2015-01-01

    Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion. PMID:25941431

  15. Elastomechanical properties of bovine veins.

    PubMed

    Rossmann, Jenn Stroud

    2010-02-01

    Veins have historically been discussed in qualitative, relative terms: "more compliant" than arteries, subject to "lower pressures". The structural and compositional differences between arteries and veins are directly related to the different functions of these vessels. Veins are often used as grafts to reroute flow from atherosclerotic arteries, and venous elasticity plays a role in the development of conditions such as varicose veins and valvular insufficiency. It is therefore of clinical interest to determine the elastomechanical properties of veins. In the current study, both tensile and vibration testing are used to obtain elastic moduli of bovine veins. Representative stress-strain data are shown, and the mechanical and failure properties reported. Nonlinear and viscoelastic behavior is observed, though most properties show little strain rate dependence. These data suggest parameters for constitutive modeling of veins and may inform the design and testing of prosthetic venous valves as well as vein grafts. PMID:20129420

  16. 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 ...

  17. Yellow fever: an update.

    PubMed

    Monath, T P

    2001-08-01

    Yellow fever, the original viral haemorrhagic fever, was one of the most feared lethal diseases before the development of an effective vaccine. Today the disease still affects as many as 200,000 persons annually in tropical regions of Africa and South America, and poses a significant hazard to unvaccinated travellers to these areas. Yellow fever is transmitted in a cycle involving monkeys and mosquitoes, but human beings can also serve as the viraemic host for mosquito infection. Recent increases in the density and distribution of the urban mosquito vector, Aedes aegypti, as well as the rise in air travel increase the risk of introduction and spread of yellow fever to North and Central America, the Caribbean and Asia. Here I review the clinical features of the disease, its pathogenesis and pathophysiology. The disease mechanisms are poorly understood and have not been the subject of modern clinical research. Since there is no specific treatment, and management of patients with the disease is extremely problematic, the emphasis is on preventative vaccination. As a zoonosis, yellow fever cannot be eradicated, but reduction of the human disease burden is achievable through routine childhood vaccination in endemic countries, with a low cost for the benefits obtained. The biological characteristics, safety, and efficacy of live attenuated, yellow fever 17D vaccine are reviewed. New applications of yellow fever 17D virus as a vector for foreign genes hold considerable promise as a means of developing new vaccines against other viruses, and possibly against cancers. PMID:11871403

  18. Hot streaks and phantom cooling in a turbine rotor passage. I - Separate effects

    NASA Technical Reports Server (NTRS)

    Roback, Richard J.; Dring, Robert P.

    1992-01-01

    Experimental documentation and analytical correlations demonstrating the effects of hot streak accumulation and phantom cooling on turbine rotor airfoil surface temperature. Test results are shown for a range of controlling variables to identify where streak accumulation and phantom cooling are most likely to be strongest. These variables include streak injection location, streak-to-free stream density ratio and coolant-to-free stream density and velocity ratios.

  19. 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.

  20. 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.

  1. Silent polypoidal choroidal vasculopathy in a patient with angioid streaks.

    PubMed

    Cebeci, Zafer; Bayraktar, Serife; Oray, Merih; Kir, Nur

    2016-01-01

    We present a case of silent polypoidal choroidal vasculopathy (PCV) in a patient with angioid streaks. PCV was detected during a routine ophthalmic examination and confirmed by fluorescein angiography, indocyanine green angiography, and optical coherence tomography. After 2 years of follow-up, the PCV remained silent without any complications. We report this rare coexistence and review literature on this topic. PMID:27463636

  2. 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.

  3. Analysis of hot streak effects on turbine rotor heat load

    SciTech Connect

    Shang, T.; Epstein, A.H.

    1997-07-01

    The influence of inlet hot streak temperature distortion on turbine blade heat load was explored on a transonic axial flow turbine stage test article using a three-dimensional, multiblade row unsteady Euler code. The turbine geometry was the same as that used for a recently reported testing of hot streak influence. Emphasis was placed on elucidating the physical and mechanisms by which hot streaks affect turbine durability. It was found that temperature distortion significantly increases both blade surface heat load nonuniformity and total blade heat load by as much as 10--30% (mainly in the pressure surface), and that the severity of this influence is a strong function of turbine geometry and flow conditions. Three physical mechanisms were identified that drive the heat load nonuniformity: buoyancy, wake convection (the Kerrebrock-Mikolajczak effect), and rotor-stator interactions. The latter can generate significant nonuniformity of the time-averaged relative frame rotor inlet temperature distribution. Dependence of these effects on turbine design variables was investigated to shed light on the design space, which minimizes the adverse effects of hot streaks.

  4. Attosecond time-resolved streaked photoemission from solids

    NASA Astrophysics Data System (ADS)

    Liao, Qing; Thumm, Uwe

    2015-05-01

    We established a quantum-mechanical model for infrared (IR) laser streaked photoelectron (PE) emission from metal solids by an ultrashort extreme ultraviolet (XUV) pulse. Special emphasis was laid on the influence of the energy dispersion of PEs inside the solids on the photoemission time delay. We first applied this model to Mg(0001) surfaces, assuming free-electron dispersion and found good agreement with measured streaked PE spectra and streaking time delays. Next, we investigate W(110) surfaces for which non-free PE dispersion must be included in order to reproduce the measured photoemission delays at different XUV central photon energies. Our model reproduces a series of measured streaked spectrograms and photoemission delays for different metal solids, including clean Mg(0001) and W(110) surfaces and Mg-covered W(110) surfaces. It incorporates modeling of the target band structure, electron mean free paths, energy dispersion, and screening of the IR laser field on the surface. Supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy under Grant No. DE-FG02-86ER13491 and NSF Grant PHY-1068752.

  5. 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.

  6. 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.

  7. A novel emaravirus is associated with redbud yellow ringspot disease.

    PubMed

    Di Bello, Patrick L; Laney, Alma G; Druciarek, Tobiasz; Ho, Thien; Gergerich, Rose C; Keller, Karen E; Martin, Robert R; Tzanetakis, Ioannis E

    2016-08-15

    Yellow ringspot is the only virus-like disease reported in redbud (Cercis spp.) with symptoms including vein clearing, chlorotic ringspots and oak-leaf pattern. A putative new emaravirus was present in all trees displaying typical yellow ringspot symptoms and the name redbud yellow ringspot associated virus is proposed. The virus genome is composed of at least five RNA segments. Two coding regions were studied to determine isolate diversity with results pointing to a homogeneous virus population. Host range was evaluated using graft transmission and by testing species found in close proximity to infected trees. Mite transmission with Aculops cercidis, the predominant species found in redbud trees in the epicenter of the disease, was evaluated but was not found to be a vector of the virus. Based on this study and the accumulated knowledge on emaravirus evolution we propose that speciation is allopatric, with vectors being a major component of the process. PMID:27262621

  8. Hitting is contagious in baseball: evidence from long hitting streaks.

    PubMed

    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 [Formula: see text] streaks of length [Formula: see text] games, including a total [Formula: see text] observations were compiled. Treatment and control sample groups ([Formula: see text]) were constructed from core lineups of players on the streaking batter's team. The percentile method bootstrap was used to calculate [Formula: see text] 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 [Formula: see text] for the treatment group was found to be [Formula: see text] to [Formula: see text] percentage points higher during hot streaks (mean difference increased [Formula: see text] points), while the batting heat index [Formula: see text] introduced here was observed to increase by [Formula: see text] points. For each performance statistic, the null hypothesis was rejected at the [Formula: see text] 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

  9. Spontaneous Iliac Vein Rupture

    PubMed Central

    Kim, Dae Hwan; Park, Hyung Sub; Lee, Taeseung

    2015-01-01

    Spontaneous iliac vein rupture (SIVR) is a rare entity, which usually occurs without a precipitating factor, but can be a life-threatening emergency often requiring an emergency operation. This is a case report of SIVR in a 62-year-old female who presented to the emergency room with left leg swelling. Workup with contrast-enhanced computed tomography revealed a left leg deep vein thrombosis with May-Thurner syndrome and a hematoma in the pelvic cavity without definite evidence of arterial bleeding. She was managed conservatively without surgical intervention, and also underwent inferior vena cava filter insertion and subsequent anticoagulation therapy for pulmonary thromboembolism. This case shows that SIVR can be successfully managed with close monitoring and conservative management, and anticoagulation may be safely applied despite the patient presenting with venous bleeding. PMID:26217647

  10. Monitoring Nonadiabatic Electron-Nuclear Dynamics in Molecules by Attosecond Streaking of Photoelectrons.

    PubMed

    Kowalewski, Markus; Bennett, Kochise; Rouxel, Jérémy R; Mukamel, Shaul

    2016-07-22

    Streaking of photoelectrons has long been used for the temporal characterization of attosecond extreme ultraviolet pulses. When the time-resolved photoelectrons originate from a coherent superposition of electronic states, they carry additional phase information, which can be retrieved by the streaking technique. In this contribution we extend the streaking formalism to include coupled electron and nuclear dynamics in molecules as well as initial coherences. We demonstrate how streaked photoelectrons offer a novel tool for monitoring nonadiabatic dynamics as it occurs in the vicinity of conical intersections and avoided crossings. Streaking can provide high time resolution direct signatures of electronic coherences, which affect many primary photochemical and biological events. PMID:27494470

  11. Monitoring Nonadiabatic Electron-Nuclear Dynamics in Molecules by Attosecond Streaking of Photoelectrons

    NASA Astrophysics Data System (ADS)

    Kowalewski, Markus; Bennett, Kochise; Rouxel, Jérémy R.; Mukamel, Shaul

    2016-07-01

    Streaking of photoelectrons has long been used for the temporal characterization of attosecond extreme ultraviolet pulses. When the time-resolved photoelectrons originate from a coherent superposition of electronic states, they carry additional phase information, which can be retrieved by the streaking technique. In this contribution we extend the streaking formalism to include coupled electron and nuclear dynamics in molecules as well as initial coherences. We demonstrate how streaked photoelectrons offer a novel tool for monitoring nonadiabatic dynamics as it occurs in the vicinity of conical intersections and avoided crossings. Streaking can provide high time resolution direct signatures of electronic coherences, which affect many primary photochemical and biological events.

  12. New Experimental Hosts of Tobacco streak virus and Absence of True Seed Transmission in Leguminous Hosts.

    PubMed

    Vemana, K; Jain, R K

    2010-10-01

    Of 70 plant species tested, 50 species were susceptible to Tobacco streak virus (TSV) on sap inoculation. Both localized (necrotic and chlorotic spots) and systemic (necrotic spots, axillary shoot proliferation, stunting, total necrosis and wilt) symptoms are observed by majority of plant species. Eleven new experimental hosts were identified viz., Amaranthus blitum var. oleracea (Chaulai sag), Celosia cristata (Cocks comb), Beta vulgaris var. bengalensis (Palak/Indian spinach), Calendula officinalis (Pot marigold), Chrysanthemum indicum, Cosmos sulphurens (Yellow cosmos), Citrullus lunatus (Watermelon), Lagenaria siceraria (Bottle gourd), Coriandrum sativum (Coriander), Hibiscus subderiffa var. subderiffa (Roselle) and Portulaca oleraceae (Little hogweed). Detected groundnut seed infection with TSV for the first time by Direct antigen coated immunosorbent assay (DAC-ELISA) using whole seed. The seed infection ranged from 18.9 to 28.9% among the seeds collected from naturally infected and sap inoculated groundnut varieties (JL 24, TMV 2, Prasuna, Kadiri 6, Kadiri 9, Anantha and Kadiri 7 Bold) belonging to spanish and virginia types. Further, TSV was detected both in pod shell and seed testa and none of the samples showed the presence of TSV either in cotyledon or embryo. Grow-out and bio-assay tests proved the absence of seed transmission in groundnut and other legume crops. Hence, TSV isolate was not a true seed transmission case under Indian conditions in legumes. PMID:23637490

  13. A variant of Rubus yellow net virus with altered genomic organization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubus yellow net virus (RYNV) is a member of the family Caulimoviridae, genus Badnavirus. RYNV infects Rubus species causing chlorosis of the tissue along the leaf veins, giving an unevenly distributed netted symptom in some cultivars of red and black raspberry. Recently, this virus was isolated and...

  14. Development of streak camera with anisotropic focusing electron optical system

    NASA Astrophysics Data System (ADS)

    Tian, J.; Ding, Y.; Cao, X.; Liu, S.; Xu, X.; Hu, X.; Wen, W.; Wang, J.; Wang, C.; Liu, H.; Dong, G.; Zhang, T.; Lu, Y.; Wang, Xi.; Liu, J.

    2013-05-01

    In this paper, the anisotropic focusing technique is used to make a novel streak tube. The salient features are the introduction of both temporally focusing electrodes and spatially focusing electric quadrupole lens. The simulation showed that physical temporal dispersion of 0.38 ps and edge spatial resolution of 56 lp/mm can be achieved. The Nd:YLF 8ps pulse laser was used to calibrate the performance index of streak camera. The static and dynamic spatial resolutions are 35 lp/mm and 25 lp/mm respectively. The dynamic range more than 950:1 and time resolution 8ps can be reached. Furthermore, the magnifications in slit and scanning direction can be adjusted respectively, so it is very convenient to select amplification needed when it is coupled with KB microscope.

  15. Megahertz streak-mode Fourier domain optical coherence tomography

    PubMed Central

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

    2011-01-01

    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

  16. Streak cameras for soft x-ray and optical radiation

    SciTech Connect

    Medecki, H.

    1983-09-01

    The principal component of a streak camera is the image converter tube. A slit-shaped photocathode transforms the radiation into a proportional emission of electrons. An electron - optics arrangement accelerates the electrons and projects them into a phosphor screen creating the image of the slit. A pair of deflection plates deflects the electronic beam along a direction perpendicular to the main dimension of the slit. Different portions of the phosphor screen show the instantaneous image of the slit with brightness proportional to the number of emitted electrons and, consequently, to the intensity of the radiation. For our x-ray streak cameras, we use the RCA C73435A image conventer tube intended for the measurement of the radiation of light and modified to have an x-ray sensitive photocathode. Practical considerations lead to the use of transparent rather than reflecting photocathodes. Several of these camera tubes are briefly described.

  17. rf streak camera based ultrafast relativistic electron diffraction.

    PubMed

    Musumeci, P; Moody, J T; Scoby, C M; Gutierrez, M S; Tran, T

    2009-01-01

    We theoretically and experimentally investigate the possibility of using a rf streak camera to time resolve in a single shot structural changes at the sub-100 fs time scale via relativistic electron diffraction. We experimentally tested this novel concept at the UCLA Pegasus rf photoinjector. Time-resolved diffraction patterns from thin Al foil are recorded. Averaging over 50 shots is required in order to get statistics sufficient to uncover a variation in time of the diffraction patterns. In the absence of an external pump laser, this is explained as due to the energy chirp on the beam out of the electron gun. With further improvements to the electron source, rf streak camera based ultrafast electron diffraction has the potential to yield truly single shot measurements of ultrafast processes. PMID:19191429

  18. 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...

  19. Yellow leaf blotch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow leaf blotch occurs worldwide in temperate climates. The disease is reported from countries in Asia, Australasia, Oceania, Europe, North America, Central America, the West Indies, and South America. In the northern Great Plains of North America, it is often the major leaf disease on alfalfa....

  20. 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

  1. Automatic coil selection for streak artifact reduction in radial MRI.

    PubMed

    Xue, Yiqun; Yu, Jiangsheng; Kang, Hyun Seon; Englander, Sarah; Rosen, Mark A; Song, Hee Kwon

    2012-02-01

    In radial MR imaging, streaking artifacts contaminating the entire field of view can arise from regions at the outer edges of the prescribed field of view. This can occur even when the Nyquist criterion is satisfied within the desired field of view. These artifacts become exacerbated when parts of the object lie in the superior/inferior regions of the scanner where the gradient strengths become weakened. When multiple coil arrays are used for signal reception, coils at the outer edges can be disabled before data acquisition to reduce the artifact levels. However, as the weakened gradient strengths near the edges often distort the object, causing the signal to become highly concentrated into a small region, the streaks are often not completely removed. Data from certain coils can also be excluded during reconstruction by visually inspecting the individual coil images, but this is impractical for routine use. In this work, a postprocessing method is proposed to automatically identify those coils whose images contain high levels of streaking for subsequent exclusion during reconstruction. The proposed method was demonstrated in vivo dynamic contrast enhanced MRI datasets acquired using a three-dimensional hybrid radial sequence. The results demonstrate that the proposed strategy substantially improves the image quality and show excellent agreement with images reconstructed with manually determined coil selection. PMID:21656562

  2. Streak artifact reduction in cardiac cone beam CT

    NASA Astrophysics Data System (ADS)

    Shechter, Gilad; Naveh, Galit; Lessick, Jonathan; Altman, Ami

    2005-04-01

    Cone beam reconstructed cardiac CT images suffer from characteristic streak artifacts that affect the quality of coronary artery imaging. These artifacts arise from inhomogeneous distribution of noise. While in non-tagged reconstruction inhomogeneity of noise distribution is mainly due to anisotropy of the attenuation of the scanned object (e.g. shoulders), in cardiac imaging it is largely influenced by the non-uniform distribution of the acquired data used for reconstructing the heart at a given phase. We use a cardiac adaptive filter to reduce these streaks. In difference to previous methods of adaptive filtering that locally smooth data points on the basis of their attenuation values, our filter is applied as a function of the noise distribution of the data as it is used in the phase selective reconstruction. We have reconstructed trans-axial images without adaptive filtering, with a regular adaptive filter and with the cardiac adaptive filter. With the cardiac adaptive filter significant reduction of streaks is achieved, and thus image quality is improved. The coronary vessel is much more pronounced in the cardiac adaptive filtered images, in slab MIP the main coronary artery branches are more visible, and non-calcified plaque is better differentiated from vessel wall. This improvement is accomplished without altering significantly the border definition of calcified plaques.

  3. 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.

  4. 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.

  5. Resolution limitations and optimization of the LLNL streak camera focus

    SciTech Connect

    Lerche, R.A.; Griffith, R.L.

    1987-09-01

    The RCA C73435 image tube is biased at voltages far from its original design in the LLNL ultrafast (10 ps) streak camera. Its output resolution at streak camera operating potentials has been measured as a function of input slit width, incident-light wavelength, and focus-grid voltage. The temporal resolution is insensitive to focus-grid voltage for a narrow (100 ..mu..m) input slit, but is very sensitive to focus-grid voltage for a wide (2 mm) input slit. At the optimum wide-slit focus voltage, temporal resolution is insensitive to slit width. Spatial resolution is nearly independent of focus-grid voltage for values that give good temporal resolution. Both temporal and spatial resolution depend on the incident-light wavelength. Data for 1.06-..mu..m light show significantly better focusing than for 0.53-..mu..m light. Streak camera operation is simulated with a computer program that calculates photoelectron trajectories. Electron ray tracing describes all of the observed effects of slit width, incident-light wavelength, and focus-grid voltage on output resolution. 7 refs.

  6. 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.

  7. 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.

  8. Stabilization of boundary layer streaks by plasma actuators

    NASA Astrophysics Data System (ADS)

    Riherd, Mark; Roy, Subrata

    2014-03-01

    A flow's transition from laminar to turbulent leads to increased levels of skin friction. In recent years, dielectric barrier discharge actuators have been shown to be able to delay the onset of turbulence in boundary layers. While the laminar to turbulent transition process can be initiated by several different instability mechanisms, so far, only stabilization of the Tollmien-Schlichting path to transition has received significant attention, leaving the stabilization of other transition paths using these actuators less explored. To fill that void, a bi-global stability analysis is used here to examine the stabilization of boundary layer streaks in a laminar boundary layer. These streaks, which are important to both transient and by-pass instability mechanisms, are damped by the addition of a flow-wise oriented plasma body force to the boundary layer. Depending on the magnitude of the plasma actuation, this damping can be up to 25% of the perturbation's kinetic energy. The damping mechanism appears to be due to highly localized effects in the immediate vicinity of the body force, and when examined using a linearized Reynolds-averaged Navier-Stokes energy balance, indicate negative production of the perturbation's kinetic energy. Parametric studies of the stabilization have also been performed, varying the magnitude of the plasma actuator's body force and the spanwise wavenumber of the actuation. Based on these parametric studies, the damping of the boundary layer streaks appears to be linear with respect to the total amount of body force applied to the flow.

  9. Analysis of extraembryonic mesodermal structure formation in the absence of morphological primitive streak.

    PubMed

    Jin, Jiu-Zhen; Zhu, Yuanqi; Warner, Dennis; Ding, Jixiang

    2016-08-01

    During mouse gastrulation, the primitive streak is formed on the posterior side of the embryo. Cells migrate out of the primitive streak to form the future mesoderm and endoderm. Fate mapping studies revealed a group of cell migrate through the proximal end of the primitive streak and give rise to the extraembryonic mesoderm tissues such as the yolk sac blood islands and allantois. However, it is not clear whether the formation of a morphological primitive streak is required for the development of these extraembryonic mesodermal tissues. Loss of the Cripto gene in mice dramatically reduces, but does not completely abolish, Nodal activity leading to the absence of a morphological primitive streak. However, embryonic erythrocytes are still formed and assembled into the blood islands. In addition, Cripto mutant embryos form allantoic buds. However, Drap1 mutant embryos have excessive Nodal activity in the epiblast cells before gastrulation and form an expanded primitive streak, but no yolk sac blood islands or allantoic bud formation. Lefty2 embryos also have elevated levels of Nodal activity in the primitive streak during gastrulation, and undergo normal blood island and allantois formation. We therefore speculate that low level of Nodal activity disrupts the formation of morphological primitive streak on the posterior side, but still allows the formation of primitive streak cells on the proximal side, which give rise to the extraembryonic mesodermal tissues formation. Excessive Nodal activity in the epiblast at pre-gastrulation stage, but not in the primitive streak cells during gastrulation, disrupts extraembryonic mesoderm development. PMID:27273137

  10. [Coronary veins and coronary sinus tributary veins in Africans].

    PubMed

    Yangni-Angate, H; Kokoua, A; Kouassi, R; Kassanyou, S; Gnagne, Y; Guessan, G N; Cowppli-Bony, P; Memel, J B

    1995-01-01

    This anatomical study carried out on 40 African adults hearts studied branches of the coronary sinus. By using of injection of the coronary arteries and corrosion of the myocardium, the study identified certain peculiarities of the small coronary vein and the posterior descending interventricular vein in Africans. PMID:8519704

  11. On the nature and visibility of crater-associated streaks on Mars

    NASA Technical Reports Server (NTRS)

    Veverka, J.; Thomas, P.; Sagan, C.

    1978-01-01

    The paper considers Mariner 9 and Viking data that contradict Kuzmin's (1975) hypothesis that all crater-associated wind streaks on Mars are depositional and consist of unresolved barchan-like dunes. According to Kuzmin's hypothesis, any streak can appear either bright or dark relative to its surroundings depending on the sun's position. The spacecraft images, however, show examples of dark and light streaks visible at the same azimuth angle of the sun. Evidence that bright and dark streaks differ both in morphology and in character is considered. It is suggested that the common ragged dark streaks are probably erosion scars while most bright streaks probably represent accumulations of bright dust-storm fallout.

  12. Hot streaks and phantom cooling in a turbine rotor passage. II - Combined effects and analytical modelling

    NASA Technical Reports Server (NTRS)

    Roback, Richard J.; Dring, Robert P.

    1992-01-01

    Experimental documentation and analytical correlations demonstrating the effects of hot streak accumulation and phantom cooling on turbine rotor airfoil surface temperature are presented. Results are shown which quantify the impact of a nonuniform temperature profile at the entrance of a turbine due to combustor-generated hot and cold streaks, and cooling air discharged from the trailing edge of the upstream stator. Experimental results are shown for a range of controlling variables to identify where streak accumulation and phantom cooling were most likely to be strongest. These variables include streak-to-free stream density ratio, streak injection location, and coolant-to-free stream density and velocity ratios. Experimental results are shown for the combined effects of hot streak and stator coolant on the adiabatic recovery temperature of the rotor.

  13. Infrared imaging of varicose veins

    NASA Astrophysics Data System (ADS)

    Noordmans, Herke Jan; de Zeeuw, Raymond; Verdaasdonk, Ruud M.; Wittens, Cees H. A.

    2004-06-01

    It has been established that varicose veins are better visualized with infrared photography. As near-infrared films are nowadays hard to get and to develop in the digital world, we investigated the use of digital photography of varicose veins. Topics that are discussed are illumination setup, photography and digital image enhancement and analysis.

  14. 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

  15. 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

  16. Complete genome sequence of a novel badnavirus, banana streak IM virus.

    PubMed

    Geering, Andrew D W; Parry, Judith N; Thomas, John E

    2011-04-01

    In 1999, banana streak disease outbreaks occurred at two locations in Australia in new banana hybrids that were being screened for fusarium wilt resistance. Two different badnaviruses, banana streak GF virus and a newly discovered virus called banana streak IM virus (BSIMV), were detected in these plants. The complete nucleotide sequence of the BSIMV genome was determined and comprised 7768 nt. Three open reading frames were detected, the first beginning with a non-conventional start codon (CUG). A 55-nt repetition in the putative pregenomic RNA promoter was also identified. Phylogenetic analysis suggests that BSIMV is most closely related to banana streak VN virus. PMID:21347843

  17. Surface properties of the Pettit wind streak on Mars Implications for sediment transport

    NASA Astrophysics Data System (ADS)

    Zimbelman, J. R.

    1986-04-01

    Satellite imagery of the Pettit streak on Amazonis Planitia are discussed in terms of the details of wind streaks and their associated sediments. Increasingly more detailed blow-ups of the available imagery demonstrate that the Pettit streak holds both a Type I bright streak (at the crater rim) and a Type II dark streak beginning at the dark patch within the crater. The lowest albedos measured, 0.20-0.22, are associated with the highest thermal inertia, indicative of grain diameters similar to medium sand, i.e., ranging from 250-350 microns. The brightest portions of the streak have albedos over 0.26 and a low thermal inertia, in the range 3-4, which implies the presence of fine-grained sand, diameters from 50-100 microns. The particle grains are less than 50 microns diameter in the surrounding plains, which have an approximately uniform albedo (0.27) and a thermal inertia of 2.5, characteristics typical of silt or clay. Current streak models describe the dark streak well, but do not account for the bright streak, which may be optically thick patches of very fine dust.

  18. 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

  19. Characterization of Brown Streak Virus-Resistant Cassava.

    PubMed

    Anjanappa, Ravi B; Mehta, Devang; Maruthi, M N; Kanju, Edward; Gruissem, Wilhelm; Vanderschuren, Hervé

    2016-07-01

    Cassava brown streak disease (CBSD) has become a major constraint to cassava production in East and Central Africa. The identification of new sources of CBSD resistance is essential to deploy CBSD mitigation strategies, as the disease is progressing westwards to new geographical areas. A stringent infection method based on top cleft-grafting combined with precise virus titer quantitation was utilized to screen 14 cassava cultivars and elite breeding lines. When inoculated with mixed infections of Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV), the scions of elite breeding lines KBH 2006/18 and KBH 2006/26 remained symptom-free during a 16-week period of virus graft inoculation, while susceptible varieties displayed typical CBSD infection symptoms at 4 weeks after grafting. The identified CBSD resistance was stable under the coinoculation of CBSV and UCBSV with cassava geminiviruses. Double-grafting experiments revealed that transmission of CBSV and UCBSV to CBSD-susceptible top scions was delayed when using intermediate scions of elite breeding lines KBH 2006/18 and KBH 2006/26. Nonetheless, comparison of virus systemic movement using scions from KBH2006/18 and a transgenic CBSD resistant 60444 line (60444-Hp9 line) showed that both CBSV and UCBSV move at undetectable levels through the stems. Further, protoplast-based assays of virus titers showed that the replication of CBSV is inhibited in the resistant line KBH2006/18, suggesting that the identified CBSD resistance is at least partially based on inhibition of virus replication. Our molecular characterization of CBSD resistance in cassava offers a robust virus-host system to further investigate the molecular determinants of CBSD resistance. PMID:27070326

  20. Sagittal vein thrombosis caused by central vein catheter.

    PubMed

    Sabzi, Feridoun; Karim, Hosein; Heydar Pour, Behzad; Faraji, Reza

    2015-01-01

    Cerebral venous thrombosis, including thrombosis of cerebral veins and major dural sinuses, is an uncommon disorder in the general population. However, it has a higher frequency among patients younger than 40 years of age, patients with thrombophilia, pregnant patients or those receiving hormonal contraceptive therapy or has foreign body such as catheter in their veins or arterial system. In this case report, we described clinical and radiological findings in a patient with protein C-S deficiency and malposition of central vein catheter. PMID:25796028

  1. Streaked radiography measurements of convergent ablator performance (invited)

    SciTech Connect

    Hicks, D. G.; Spears, B. K.; Braun, D. G.; Olson, R. E.; Sorce, C. M.; Celliers, P. M.; Collins, G. W.; Landen, O. L.

    2010-10-15

    The velocity and remaining ablator mass of an imploding capsule are critical metrics for assessing the progress toward ignition of an inertially confined fusion experiment. These and other ablator rocket parameters have been measured using a single streaked x-ray radiograph. A regularization technique has been used to determine the ablator density profile {rho}(r) at each time step; moments of {rho}(r) then provide the areal density, average radius, and mass of the unablated, or remaining, ablator material, with the velocity determined from the time derivative of the average radius. The technique has been implemented on experiments at the OMEGA laser facility.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. [Further development of a streak retinoscope with calibrated collimator].

    PubMed

    Rohrschneider, K; Koch, H R

    1992-08-01

    Development and rationale of a new streak retinoscope have been discussed in an earlier paper. In contrast to classical retinoscopy this retinoscope determines the refraction by forming the narrowest streak in the test person's pupil with a calibrated collimator. In addition to the first prototype the extension of the lamp according to variation of the refraction is measured electronically and the data are transposed into a computer. This allows to freely choose a working distance in a range from about 30 to 120 cm and therefore it is possible to examine restless patients. Accuracy of the measurement was less than or equal to 0.25 D for Ametropia from -0.5 to 5.0 D in a working distance of 30 cm or from -4.0 to -1.5 D in 100 cm. In most persons it is not necessary to use additional glasses during refraction by choosing the adequate distance. Therefore this method can help to refract kids and other persons which could not be refracted by use of glasses. In addition this method excludes the accommodation of the patient as apposed to regular refractometers. PMID:1434382

  7. Hepatoportography via the Umbilical Vein

    PubMed Central

    White, J. J.; Skinner, G. B.; MacLean, L. D.

    1966-01-01

    The umbilical vein in adults is patent but collapsed. There is a membranous valve at its entrance into the left portal vein. Cannulation of the portal vein via the umbilical vein permits direct access to the portal system for portography and hepatography. This procedure was performed under local or general anesthesia in 30 patients and was successful in 22. It is useful in the investigation of patients with portal hypertension, and suspected intrahepatic tumours or abscesses. It gives excellent contrast visualization of the liver and definition of lesions as small as 1.0 cm. This technique is superior to both hepatic scanning and splenoportography. ImagesFig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:5924949

  8. 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 ...

  9. THEMIS-IR Emissivity Spectrum of a Large "Dark Streak" near Olympus Mons

    NASA Astrophysics Data System (ADS)

    Brumby, S. P.

    2004-03-01

    "Dark streaks" are unusual transient surface features found on Mars. 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.

  10. 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.

  11. 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.

  12. Deltoid Branch of Thoracoacromial Vein

    PubMed Central

    Su, Ta-Wei; Wu, Ching-Feng; Fu, Jui-Ying; Ko, Po-Jen; Yu, Sheng-Yueh; Kao, Tsung-Chi; Hsieh, Hong-Chang; Wu, Ching-Yang

    2015-01-01

    Abstract An entry vessel is crucial for intravenous port implantation. A safe alternative entry vessel that can be easily explored is crucial for patients without feasible cephalic vein or for those who need port reimplantation because of disease relapse. In this study, we tried to analyze the safety and feasibility of catheter implantation via the deltoid branch of the thoracoacromial vein. From March 2012 to November 2013, 802 consecutive oncology patients who had received intravenous port implantation via the superior vena cava were enrolled in this study. The functional results and complications of different entry vessels were compared. The majority of patients (93.6%) could be identified as thoracoacromial vessel. The deltoid branch of the thoracoacromial vein is located on the medial aspect of the deltopectoral groove beneath the pectoralis major muscle (85.8%) and in the deep part of the deltopectoral groove (14.2%). Due to the various calibers employed and tortuous routes followed, we utilized 3 different methods for catheter implantation, including vessel cutdown (47.4%), wire assisted (17.9%), and modified puncture method (34.6%). The functional results and complication rate were similar to other entry vessels. The deltoid branch of the thoracoacromial vein is located in the neighborhood of the cephalic vein. The functional results of intravenous port implantation via the deltoid branch of the thoracoacromial vein are similar to other entry vessels. It is a safe alternative entry vessel for intravenous port implantation. PMID:25929903

  13. Averaging picosecond streak camera for time resolved x-ray and XUV spectroscopy of ultrashort plasmas

    NASA Astrophysics Data System (ADS)

    Maksimchuk, A.; Nantel, M.; Workman, J.; Umstadter, D.; Mourou, G.; Pikuz, S.

    1996-11-01

    We have developed an averaging picosecond x-ray streak camera that uses a DC-biased semi-insulating GaAs photoconductive switch as a generator of a high-voltage ramp for the deflection plates of the streak camera. The streak camera is operated at a sweep speed of up to 8 ps/mm, with a shot-to-shot jitter of 1 ps. The streak camera driven by this switch is absolutely synhronized with the femtosecond laser pulse and allows the direct accumulation of the x-ray temporal signals at a 10 Hz repetition rate. The streak camera has been used for the investigation of temporal behavior of keV x-ray lines and spectrally resolved XUV emission from solid target at the laser intensity of 10^17 W/cm^2. This work is supported by NSF under Grant STC PHY 8920108.

  14. 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.

  15. Sub-picosecond streak camera measurements at LLNL: From IR to x-rays

    SciTech Connect

    Kuba, J; Shepherd, R; Booth, R; Steward, R; Lee, E W; Cross, R R; Springer, P T

    2003-12-21

    An ultra fast, sub-picosecond resolution streak camera has been recently developed at the LLNL. The camera is a versatile instrument with a wide operating wavelength range. The temporal resolution of up to 300 fs can be achieved, with routine operation at 500 fs. The streak camera has been operated in a wide wavelength range from IR to x-rays up to 2 keV. In this paper we briefly review the main design features that result in the unique properties of the streak camera and present its several scientific applications: (1) Streak camera characterization using a Michelson interferometer in visible range, (2) temporally resolved study of a transient x-ray laser at 14.7 nm, which enabled us to vary the x-ray laser pulse duration from {approx}2-6 ps by changing the pump laser parameters, and (3) an example of a time-resolved spectroscopy experiment with the streak camera.

  16. 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

  17. 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.

  18. 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.

  19. On the convectively unstable nature of optimal streaks in boundary layers

    NASA Astrophysics Data System (ADS)

    Brandt, Luca; Cossu, Carlo; Chomaz, Jean-Marc; Huerre, Patrick; Henningson, Dan S.

    2003-06-01

    The objective of the study is to determine the absolute/convective nature of the secondary instability experienced by finite-amplitude streaks in the flat-plate boundary layer. A family of parallel streaky base flows is defined by extracting velocity profiles from direct numerical simulations of nonlinearly saturated optimal streaks. The computed impulse response of the streaky base flows is then determined as a function of streak amplitude and streamwise station. Both the temporal and spatio-temporal instability properties are directly retrieved from the impulse response wave packet, without solving the dispersion relation or applying the pinching point criterion in the complex wavenumber plane. The instability of optimal streaks is found to be unambiguously convective for all streak amplitudes and streamwise stations. It is more convective than the Blasius boundary layer in the absence of streaks; the trailing edge-velocity of a Tollmien Schlichting wave packet in the Blasius boundary layer is around 35% of the free-stream velocity, while that of the wave packet riding on the streaky base flow is around 70%. This is because the streak instability is primarily induced by the spanwise shear and the associated Reynolds stress production term is located further away from the wall, in a larger velocity region, than for the Tollmien Schlichting instability. The streak impulse response consists of the sinuous mode of instability triggered by the spanwise wake-like profile, as confirmed by comparing the numerical results with the absolute/convective instability properties of the family of two-dimensional wakes introduced by Monkewitz (1988). The convective nature of the secondary streak instability implies that the type of bypass transition studied here involves streaks that behave as amplifiers of external noise.

  20. 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

  1. High-speed TV cameras for streak tube readout

    SciTech Connect

    Yates, G.J.; Gallegos, R.A.; Holmes, V.H. ); Turko, B.T. )

    1991-01-01

    Two fast framing TV cameras have been characterized and compared as readout media for imaging of 40 mm diameter streak tube (P-11) phosphor screens. One camera is based upon a Focus-Projection-Scan (FPS) high-speed electrostatic deflected vidicon with 30-mm-diameter PbO target. The other uses an interline transfer charge-coupled device (CCD) with 8.8 {times} 11.4 mm rectangular Si target. The field-of-view (FOV), resolution, responsivity, and dynamic range provided by both cameras when exposed to short duration ({approx} 10 {mu} full width at half maximum (FWHM)) transient illumination followed by a single field readout period of {lt}3 ms are presented. 11 refs., 8 figs., 3 tabs.

  2. 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.

  3. Steering continuum electron dynamics by low-energy attosecond streaking

    NASA Astrophysics Data System (ADS)

    Geng, Ji-Wei; Xiong, Wei-Hao; Xiao, Xiang-Ru; Gong, Qihuang; Peng, Liang-You

    2016-08-01

    A semiclassical model is developed to understand the electronic dynamics in the low-energy attosecond streaking. Under a relatively strong infrared (IR) pulse, the low-energy part of photoelectrons initialized by a single attosecond pulse (SAP) can either rescatter with the ionic core and induce interferences structures in the momentum spectra of the ionized electrons or be recaptured into the Rydberg states. The Coulomb potential plays essential roles in both the electron rescattering and recapturing processes. We find that by changing the time delay between the SAP and the IR pulse, the photoelectrons yield or the population of the Rydberg states can be effectively controlled. The present study demonstrates a fascinating way to steer the electron motion in the continuum.

  4. Cloning and sequence analysis of banana streak virus DNA.

    PubMed

    Harper, G; Hull, R

    1998-01-01

    Banana streak virus (BSV), a member of the Badnavirus group of plant viruses, causes severe problems in banana cultivation, reducing fruit yield and restricting plant breeding and the movement of germplasm. Current detection methods are relatively insensitive. In order to develop a PCR-based diagnostic method that is both reliable and sensitive, the genome of a Nigerian isolate of BSV has been sequenced and shown to comprise 7389 bp and to be organized in a manner characteristic of badnaviruses. Comparison of this sequence with those of other badnaviruses showed that BSV is a distinct virus. PCR with primers based on sequence data indicated that BSV sequences are present in the banana genome. PMID:9926402

  5. 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

  6. Illusory Streaks from Corners and Their Perceptual Integration

    PubMed Central

    Roncato, Sergio; Guidi, Stefano; Parlangeli, Oronzo; Battaglini, Luca

    2016-01-01

    Perceptual grouping appears both as organized forms of real figural units and as illusory or “phantom” figures. The phenomenon is visible in the Hermann grid and in configurations which generate color spreading, e.g., “neon effects.” These configurations, generally regular repetitive patterns, appear to be crossed by illusory bands filled with a brighter shade or a colored tinge connecting the various loci of illusory effects. In this work, we explore a particular new illusion showing a grouping effect. It manifests as illusory streaks irradiating from the vertexes of angular contours and connecting pairs of figures nearby. It is only clearly visible when more than one figure is shown, and takes the shape of a net crossing their corners. Although the grouping effect is vivid, the local source of the illusion is completely hidden. Theories explaining this effect as due to the irradiation of illusory streaks (mainly that of Grossberg and Mingolla, 1985a,b) do not fully explain the figural patterns presented here. Illusory effects have already been documented at the angles of various figures, causing them to alter in amplitude and brightness; however, the figure illustrated here appears to have different features and location. Phenomenological observations and an experiment were conducted to assess the role played by geometric and photometric parameters in this illusion. Results showed that sharp angles, in low contrast with the surround, are the main source of the illusion which, however, only becomes visible when at least two figures are close together. These findings are discussed with respect to theories of contour processing and perceptual grouping, and in relation to other illusions. PMID:27445922

  7. Illusory Streaks from Corners and Their Perceptual Integration.

    PubMed

    Roncato, Sergio; Guidi, Stefano; Parlangeli, Oronzo; Battaglini, Luca

    2016-01-01

    Perceptual grouping appears both as organized forms of real figural units and as illusory or "phantom" figures. The phenomenon is visible in the Hermann grid and in configurations which generate color spreading, e.g., "neon effects." These configurations, generally regular repetitive patterns, appear to be crossed by illusory bands filled with a brighter shade or a colored tinge connecting the various loci of illusory effects. In this work, we explore a particular new illusion showing a grouping effect. It manifests as illusory streaks irradiating from the vertexes of angular contours and connecting pairs of figures nearby. It is only clearly visible when more than one figure is shown, and takes the shape of a net crossing their corners. Although the grouping effect is vivid, the local source of the illusion is completely hidden. Theories explaining this effect as due to the irradiation of illusory streaks (mainly that of Grossberg and Mingolla, 1985a,b) do not fully explain the figural patterns presented here. Illusory effects have already been documented at the angles of various figures, causing them to alter in amplitude and brightness; however, the figure illustrated here appears to have different features and location. Phenomenological observations and an experiment were conducted to assess the role played by geometric and photometric parameters in this illusion. Results showed that sharp angles, in low contrast with the surround, are the main source of the illusion which, however, only becomes visible when at least two figures are close together. These findings are discussed with respect to theories of contour processing and perceptual grouping, and in relation to other illusions. PMID:27445922

  8. Isolation and expression analysis of peanut chlorotic streak caulimovirus (PClSV) full-length transcript (FLt) promoter in transgenic plants.

    PubMed

    Maiti, I B; Shepherd, R J

    1998-03-17

    A promoter fragment from peanut chlorotic streak caulimovirus (PClSV) full-length transcript (FLt) was identified and later modified to have duplicated enhancer domain. The FLt promoter with its single or double enhancer domains, fused with the GUS reporter gene to form chimeric gene constructs, showed a high level of expression of these genes in cells and transgenic plants. The FLt promoter with its double enhancer domain gives an average threefold greater expression of genes compared to the FLt promoter with its single enhancer domain in transgenic plants. In young seedlings the expression was in the order root > leaf > stem. The histochemical GUS assay in young seedlings showed more activity in root tips and leaf midribs, veins, and other vascular tissues. The expression from the PClSV FLt promoter was compared with that from the figwort mosaic virus promoter in transgenic plants. These constitutive promoters were comparable in respect to GUS expression level. PMID:9514942

  9. Dust Devils Seen Streaking Across Mars: PART 1--What Are These?

    NASA Technical Reports Server (NTRS)

    2000-01-01

    PIA02376 [figure removed for brevity, see original site]

    Dark streaks, everywhere! Many Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images of the middle latitudes of the northern and southern hemispheres of Mars show wild patterns of criss-crossing dark streaks. Many of these streaks are straight and narrow, others exhibit curly arcs, twists, and loops. They often cross over hills, run straight across dunes and ripples, and go through fields of house-sized boulders. The two examples shown above were acquired in the last three months. Both pictures are illuminated by sunlight from the upper left. The first picture (left), showing dark streaks on the rippled flats of Argyre Planitia, covers an area 3 km by 5 km (1.9 by 3.1 miles) at a latitude of 51oS. The second picture (right) shows an area approximately 3 km by 5 km in Promethei Terra at a latitude of 58oS.

    For many months the MOC science team was seeing streaks such as these, but were uncertain how they formed. One speculation was that they might result from the passage of dust devils. Each dust devil would leave a dark streak by removing bright dust from the terrain in its path, revealing a darker surface underneath. An image described by the MOC team in July 1998 showed examples of streaks that were, at the time, speculated to be caused by dust devils.

  10. Flat-field response and geometric distortion measurements of optical streak cameras

    SciTech Connect

    Montgomery, D.S.; Drake, R.P.; Jones, B.A.; Wiedwald, J.D.

    1987-08-01

    To accurately measure pulse amplitude, shape, and relative time histories of optical signals with an optical streak camera, it is necessary to correct each recorded image for spatially-dependent gain nonuniformity and geometric distortion. Gain nonuniformities arise from sensitivity variations in the streak-tube photocathode, phosphor screen, image-intensifier tube, and image recording system. These nonuniformities may be severe, and have been observed to be on the order of 100% for some LLNL optical streak cameras. Geometric distortion due to optical couplings, electron-optics, and sweep nonlinearity not only affects pulse position and timing measurements, but affects pulse amplitude and shape measurements as well. By using a 1.053-..mu..m, long-pulse, high-power laser to generate a spatially and temporally uniform source as input to the streak camera, the combined effects of flat-field response and geometric distortion can be measured under the normal dynamic operation of cameras with S-1 photocathodes. Additionally, by using the same laser system to generate a train of short pulses that can be spatially modulated at the input of the streak camera, we can effectively create a two-dimensional grid of equally-spaced pulses. This allows a dynamic measurement of the geometric distortion of the streak camera. We will discuss the techniques involved in performing these calibrations, will present some of the measured results for LLNL optical streak cameras, and will discuss software methods to correct for these effects. 6 refs., 6 figs.

  11. Portal Vein Thrombosis in Cirrhosis

    PubMed Central

    Raja, Kaiser; Jacob, Mathew; Asthana, Sonal

    2013-01-01

    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

  12. 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 3 cm 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 2.5 mg once daily for 6 weeks 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

  13. Stabilization of the hypersonic boundary layer by finite-amplitude streaks

    NASA Astrophysics Data System (ADS)

    Ren, Jie; Fu, Song; Hanifi, Ardeshir

    2016-02-01

    Stabilization of two-dimensional disturbances in hypersonic boundary layer flows by finite-amplitude streaks is investigated using nonlinear parabolized stability equations. The boundary-layer flows at Mach numbers 4.5 and 6.0 are studied in which both first and second modes are supported. The streaks considered here are driven either by the so-called optimal perturbations (Klebanoff-type) or the centrifugal instability (Görtler-type). When the streak amplitude is in an appropriate range, i.e., large enough to modulate the laminar boundary layer but low enough to not trigger secondary instability, both first and second modes can effectively be suppressed.

  14. Improvements in Off-Center Focusing in an X-ray Streak Camera

    SciTech Connect

    McDonald, J W; Weber, F; Holder, J P; Bell, P M

    2003-07-17

    Due to the planar construction of present x-ray streak tubes significant off-center defocusing is observed in both static and dynamic images taken with one-dimensional resolution slits. Based on the streak tube geometry curved photocathodes with radii of curvature ranging from 3.5 to 18 inches have been fabricated. We report initial off-center focusing performance data on the evaluation of these ''improved'' photocathodes in an X-ray streak camera and an update on the theoretical simulations to predict the optimum cathode curvature.

  15. 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.

  16. 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.

  17. 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

  18. Yellow Fever Virus Infection

    PubMed Central

    David-West, Tam. S.; Smith, J. A.

    1971-01-01

    A sequential and quantitative survey of brain and liver of suckling mice for infective virus and complement-fixing antigen, after infection with yellow fever virus, showed that while there was progressive increase of infective virus content in both organs, only the brain showed a corresponding rise in CF antigen. Histopathological examination revealed that the liver was not significantly involved. The target organ was the brain, where the progressive pathological changes culminated in an acute encephalitis by the 3rd day of experiment. Organ destruction began with the molecular layer of the grey matter. But by the 4th day after infection the entire cerebral cortex was involved. At the initial stages the hippocampus was particularly affected. Tissue damage did not appear to be entirely due to the differential quantitative localization of infective virus. It was hypothesized that the CF antigen acting singly or in conjunction with some hypothetical proteins may be principally involved in the pathological outcome of the disease. ImagesFigs. 7-9Figs. 3-6 PMID:5582071

  19. 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; Djikeng, Appolinaire; 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

  20. 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

  1. The Treatment of Varicose Veins

    PubMed Central

    Subramonia, S; Lees, TA

    2007-01-01

    INTRODUCTION Over the past few years, there has been a move to less invasive endoluminal methods in the treatment of lower limb varicose veins combined with a renewed interest in sclerotherapy, with the recent addition of foam sclerotherapy. The development of these new techniques has led many to question some of the more conventional teaching on the treatment of varicose veins. This review examines these new treatments for lower limb varicose veins and the current evidence for their use. MATERIALS AND METHODS An extensive search of available electronic and paper-based databases was performed to identify studies relevant to the treatment of varicose veins with particular emphasis on those published within the last 10 years. These were analysed by both reviewers independently. RESULTS There is no single method of treatment appropriate for all cases. Conventional surgery is safe and effective and is still widely practised. Whilst the new treatments may be popular with both surgeons and patients, it is important that they are carefully evaluated not only for their clinical benefits and complications when compared to existing treatments but also for their cost prior to their wider acceptance into clinical practice. PMID:17346396

  2. Diagnosis of deep vein thrombosis.

    PubMed Central

    Douketis, J. D.; Ginsberg, J. S.

    1996-01-01

    Deep vein thrombosis (DVT), a common disease, can be difficult to diagnose because its clinical features are nonspecific. Venography is the standard test, but other less expensive, easily performed, noninvasive tests are available. At present, duplex ultrasonography is the noninvasive test of choice. PMID:8616289

  3. Varicose veins - what to ask your doctor

    MedlinePlus

    ... Below are some questions you may want to ask your health care provider to help you take ... What to ask your doctor about varicose veins; Venous insufficiency - what to ask your doctor; Vein stripping - what to ask your ...

  4. Streak camera recording of shock wave transit times at large distances using laser illumination

    NASA Astrophysics Data System (ADS)

    Tyburczy, J. A.; Blayney, J. L.; Miller, W. F.; Ahrens, T. J.

    1984-09-01

    A pulsed laser illumination system for streak camera recording of impact-induced shock wave transit times (˜1 μs) during impact experiments is described. Laser illumination of centimeter-sized subjects offers many advantages over diffuse illumination techniques for streak photography. Source-to-sample and sample-to-camera distances of ˜100 to 102 m can be employed. Light filtering, and simultaneous recording of both the impact event and the camera streak rate calibration, can be carried out easily. For use in such a system we describe a Pockels cell controller in which the reference 10-MHz oscillator signal is synchronously divided down to 38 Hz to provide a trigger signal for laser and streak camera testing.

  5. 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.

  6. 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.

  7. Standard design for National Ignition Facility x-ray streak and framing camerasa)

    NASA Astrophysics Data System (ADS)

    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.

  8. 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

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

    PubMed Central

    Fabiańska, Justyna; Kassier, Günther; 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

  10. 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

  11. Characterization results from several commercial soft x-ray streak cameras

    SciTech Connect

    Stradling, G.L.; Studebaker, J.K.; Cavailler, C.; Launspach, J.; Planes, J.

    1986-01-01

    The spatio-temporal performance of four soft x-ray streak cameras has been characterized. The objective in evaluating the performance capability of these instruments is to enable us to optimize experiment designs, to encourage quantitative analysis of streak data and to educate the ultra high speed photography and photonics community about the x-ray detector performance which is available. These measurements have been made collaboratively over the space of two years at the Forge pulsed x-ray source at Los Alamos and at the Ketjak laser facility an CEA Limeil-Valenton. The x-ray pulse lengths used for these measurements at these facilities were 150 psec and 50 psec respectively. The results are presented as dynamically-measured modulation transfer functions. Limiting temporal resolution values were also calculated. Emphasis is placed upon shot noise statistical limitations in the analysis of the data. Space charge repulsion in the streak tube limits the peak flux at ultra short experiments duration times. This limit results in a reduction of total signal and a decrease in signal to noise ratio in the streak image. The four cameras perform well with 20 1p/mm resolution discernable in data from the French C650X, the Hadland X-Chron 540 and the Hamamatsu C1936X streak cameras. The Kentech x-ray streak camera has lower modulation and does not resolve below 10 1p/mm but has a longer photocathode. The C650X bi-lamellar design shows uniform high fidelity recording across both spatial and temporal dimensions. The other three streak cameras show resolution degradation off axis. This must be weighed against a 10X lower streak tube throughput for the C650X.

  12. Measurement of width and intensity of particle streaks in turbulent flows

    NASA Astrophysics Data System (ADS)

    Håkansson, Karl M. O.; Kvick, Mathias; Lundell, Fredrik; Prahl Wittberg, Lisa; Söderberg, L. Daniel

    2013-06-01

    Fibre streaks are observed in experiments with fibre suspensions in a turbulent half-channel flow. The preferential concentration methods, most commonly used to quantify preferential particle concentration, are in one dimension found to be concentration dependent. Two different new streak quantification methods are evaluated, one based on Voronoi analysis and the other based on artificial particles with an assigned fixed width. The width of the particle streaks and a measure of the intensity of the streaks, i.e. streakiness, are sought. Both methods are based on the auto-correlation of a signal, generated by summing images in the direction of the streaks. Common for both methods is a severe concentration dependency, verified in experiments keeping the flow conditions constant while the (very dilute) concentration of fibres is altered. The fixed width method is shown to be the most suitable method, being more robust and less computationally expensive. By assuming the concentration dependence to be related to random noise, an expression is derived, which is shown to make the streak width and the streakiness independent of the concentration even at as low concentrations as 0.05 particles per pixel column in an image. The streakiness is obtained by applying an artificial particle width equal to 20 % of the streak width. This artificial particle width is in this study found to be large enough to smoothen the correlation without altering the streakiness nor the streak width. It is concluded that in order to make quantitative comparisons between different experiments or simulations, the evaluation has to be performed with care and be very well documented.

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

    PubMed

    Bühler, Jonas; Rishmawi, Louai; Pflugfelder, Daniel; Huber, Gregor; Scharr, Hanno; Hülskamp, 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

  14. 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.

  15. 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.

  16. 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

  17. Black leaf streak disease affects starch metabolism in banana fruit.

    PubMed

    Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

    2013-06-12

    Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots. PMID:23692371

  18. 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.

  19. Prediction of long saphenous vein graft adaptation.

    PubMed

    Davies, A H; Magee, T R; Hayward, J K; Baird, R N; Horrocks, M

    1994-07-01

    The ability of vein to dilate may allow smaller veins to be used for bypass if this change could be predicted. Sixty patients undergoing femorodistal popliteal or infrapopliteal bypass have had their long saphenous vein studied. Diameter measurements of the long saphenous vein have been performed using an ATL Duplex scanner at the groin, mid-thigh and knee. Measurements were performed preoperatively both at rest and with a venous occlusion cuff to dilate the vein and subsequently at 7 days and 3, 6, 9, 12 months after implantation. The mean diameter of the vein at the mid thigh was 4.2 mm non dilated, 5.1 mm with occlusion, 5.4 mm 7 days postoperatively and 5.5 mm at 12 months (p < 0.01 ANOVA). The mean diameter of the vein at the knee was 3.8 mm non-dilated, 4.8 mm with occlusion, 4.8 mm at 7 days and 5.0 mm at 12 months after operation (p < 0.01 ANOVA). If the minimum resting internal diameter of vein regarded as being suitable for bypass was 3 mm, this technique would have increased the vein utilisation rate by 22%. These results show that by using a technique of venous occlusion at the time of preoperative vein mapping the adaptive response of the vein can be predicted and this can result in an increased rate of vein utilisation. PMID:8088400

  20. Optimizing Data Recording for the NIF Core Diagnostic X-ray Streak Camera

    SciTech Connect

    Kalantar, D H; Bell, P M; Perry, T S; Sewall, N; Diamond, C; Piston, K

    2000-06-13

    The x-ray streak camera is an important instrument for recording a continuous time history of x-ray emitted from laser target experiments. X-ray streak cameras were used to diagnose experiments in inertially confined fusion and high energy density sciences on the Nova laser. These streak cameras are now used for similar experiments conducted at the OMEGA laser facility, and cameras of this type will be used for experiments on the National Ignition Facility (NIF). The Nova x-ray streak cameras (SSCs) used a sealed optical image intensifier coupled to film to record the streaked x-ray data. In order to develop the core x-ray streak camera for NIF (ref Kimbrough) using a CCD based recording system, we evaluate the performance of the SSCs under a variety of detector configurations. We performed laboratory bench characterization tests of the SSCs to measure the spatial resolution and to evaluate the dynamic range and signal to noise for different configurations of the SSC. We present results of these tests here.

  1. Effects of streaking laser intensity on the characterization of isolated attosecond pulses

    NASA Astrophysics Data System (ADS)

    Wang, He; Khan, Sabih; Chini, Michael; Chen, Shouyuan; Chang, Zenghu

    2009-05-01

    Single isolated attosecond extreme ultraviolet (XUV) pulses can be characterized by streaking photoelectrons using a near infrared (NIR) laser field. Classically, the streaking resolution is determined by the Rayleigh criterion, which requires the minimum NIR intensity of 5.5x10^13 W/cm^2 to resolve 90 as XUV pulses. Under such high NIR intensity, the electrons generated from multi-photon processes overlap with the streaked electrons in the spectrogram, which unavoidably introduces errors in the final XUV reconstruction. When the FROG-CRAB (Frequency-Resolved Optical Gating for Complete Reconstruction of Attosecond Bursts) technique is used to reconstruct the XUV pulses from the spectrogram, it was found that the minimum streaking intensity needed to resolve single attosecond pulses is dependent on the maximum count of the spectrogram. With a peak count of 100 in the spectrogram, chirped attosecond pulses with spectral bandwidth supporting 90-as transform limited pulse durations can be retrieved from the spectrogram with streaking intensity two orders of magnitude smaller than that derived from the Rayleigh criterion. Such low streaking field intensity is desirable to suppress the ATI background, which is important for the characterization of even shorter XUV attosecond pulses because it significantly reduces the intensity constraints on the experiments.

  2. 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.

  3. On the origin and evolution of streaks in polymeric shear flows

    NASA Astrophysics Data System (ADS)

    Page, Jacob; Zaki, Tamer

    2013-11-01

    Streaks are a ubiquitous feature in transitional shear flows of both Newtonian and complex fluids. A model problem is formulated where streaks are generated in response to forcing by a decaying streamwise vortex in an Oldroyd-B fluid, and the effects of inertia and elasticity are examined. The dynamics are found to be largely governed by a single parameter: the ratio of the solvent diffusion to the polymer relaxation timescales. When the time scales are disparate, the ``quasi-Newtonian'' and ``elastic'' dynamics can be distinguished. The ``quasi-Newtonian'' evolution of the streaks in the polymeric flow matches the Newtonian equivalent at the same total (solvent) Reynolds number when polymer relaxation is very fast (slow). The ``elastic'' response is significant, when the polymer relaxation time is long, and leads to significant streak amplification even with very weak inertia. When the diffusion and polymer relaxation timescales are commensurate, the streaks are re-energised in a periodic cycle. This behaviour is enhanced in the instantaneously elastic limit where the governing equation reduces to a wave equation with harmonic forcing. The streak re-energisation is demonstrated to be a superposition of trapped inertio-elastic shear waves.

  4. Spatial relationships among the cellular tapetum, visual streak and rod density in dogs

    PubMed Central

    YAMAUE, Yasuhiro; HOSAKA, Yoshinao Z.; UEHARA, Masato

    2014-01-01

    The dog visual system is well suited to dim light conditions due to rod-dominated retina and the reflective tapetum. The topographical distributions of rods and thickness of the tapetum of the dog were quantified in retinal whole mounts stained with thionine, and spatial relationships among the tapetum, rod density and visual streak of high ganglion cell density were elucidated. The relationship between the retina and tapetum was analyzed in parasagittal sections stained with thionine or hematoxylin-eosin. The tapetum was thick in its center, and the thickest part consisted of 9 to 12 tapetal cell layers. Rod density ranged from 200,000 to 540,000/mm2. Maximum rod density was found in the area dorsal to the visual streak, and the density in that area was significantly higher than the rod density in the visual streak and accorded spatially with the thickest part of the tapetum. The horizontal visual streak was found over the horizontal line through the optic disc in the temporal half and extended slightly into the nasal half. The central area of the highest density of ganglion cells was approximately located midway between the nasal and temporal ends of the visual streak. The visual streak was located within the tapetal area, but ventrally to the thick part of the tapetum. PMID:25728250

  5. Seasonal and secular variation of wind streaks on Mars - An analysis of Mariner 9 and Viking data

    NASA Technical Reports Server (NTRS)

    Thomas, P.; Veverka, J.

    1979-01-01

    Viking orbiter observations extending over 1 Martian year have been used in conjunction with Mariner 9 data obtained in 1971-1972 to study the seasonal and secular behavior of several kinds of wind streaks. Most bright streaks, inferred to consist of dust storm fallout in the lees of obstacles, have changed very little in form or orientation over a period of 3 Martian years. Some are extremely stable and have experienced no effective eolian action over the 3 years. A few bright streaks changed rapidly during global dust storms; these streaks are located in areas subject to both global and topographic winds. Viking images have shown for the first time that dark, erosional streaks are stable from the time of their formation after major dust storms until the onset of the next episode of major storm activity. Available evidence shows that the large, dark streaks in Oxia Palus consist of material deflated from dune fields within the associated craters. These streaks lengthened secularly since 1972; changes appear to occur episodically during southern summer. The great majority of all streaks reflect winds during the period from late southern spring to early southern fall, although some changes occur throughout the year. The global pattern of wind streaks and the variability of the streaks thus depend strongly upon the current south-north asymmetry of seasons on Mars.

  6. 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.

  7. 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.

  8. Abnormal patterns of the renal veins

    PubMed Central

    Azari, Hassan; Abedinzadeh, Mehdi

    2012-01-01

    Knowledge of the renal vascular anatomy may greatly contribute to the success of surgical, invasive and radiological procedures of the retroperitoneal region. Here, morphometric and histological studies of a human cadaveric specimen presented a complex, anomalous pattern of renal veins. The left renal vein had an oblique retro-aortic course and received two lumbar veins. It bifurcated near its drainage point into the inferior vena cava. The right renal vein received the right testicular vein. In addition, the left kidney was located at a low position. The spleen was enlarged. The present case is unique and provides information that may help surgeons or angiologists to apply safer interventions. PMID:22536553

  9. Mechanical buckling of veins under internal pressure.

    PubMed

    Martinez, Ricky; Fierro, Cesar A; Shireman, Paula K; Han, Hai-Chao

    2010-04-01

    Venous tortuosity is associated with multiple disease states and is often thought to be a consequence of venous hypertension and chronic venous disease. However, the underlying mechanisms of vein tortuosity are unclear. We hypothesized that increased pressure causes vein buckling that leads to a tortuous appearance. The specific aim of this study was to determine the critical buckling pressure of veins. We determined the buckling pressure of porcine jugular veins and measured the mechanical properties of these veins. Our results showed that the veins buckle when the transmural pressure exceeds a critical pressure that is strongly related to the axial stretch ratio in the veins. The critical pressures of the eight veins tested were 14.2 +/- 5.4 and 26.4 +/- 9.0 mmHg at axial stretch ratio 1.5 and 1.7, respectively. In conclusion, veins buckle into a tortuous shape at high lumen pressures or reduced axial stretch ratios. Our results are useful in understanding the development of venous tortuosity associated with varicose veins, venous valvular insufficiency, diabetic retinopathy, and vein grafts. PMID:20094913

  10. Mechanical Buckling of Veins under Internal Pressure

    PubMed Central

    Martinez, Ricky; Fierro, Cesar A.; Shireman, Paula K.; Han, Hai-Chao

    2010-01-01

    Venous tortuosity is associated with multiple disease states and is often thought to be a consequence of venous hypertension and chronic venous disease. However, the underlying mechanisms of vein tortuosity are unclear. We hypothesized that increased pressure causes vein buckling that leads to a tortuous appearance. The specific aim of this study was to determine the critical buckling pressure of veins. We determined the buckling pressure of porcine jugular veins and measured the mechanical properties of these veins. Our results showed that veins buckle when the transmural pressure exceeds a critical pressure that is strongly related to the axial stretch ratio in the veins. The critical pressures of the eight veins tested were 14.2 ± 5.4 mmHg and 26.4 ± 9.0 mmHg at axial stretch ratio 1.5 and 1.7, respectively. In conclusion, veins buckle into a tortuous shape at high lumen pressures or reduced axial stretch ratios. Our results are useful in understanding the development of venous tortuosity associated with varicose veins, venous valvular insufficiency, diabetic retinopathy and vein grafts. PMID:20094913

  11. Leiomyosarcoma of the renal vein.

    PubMed

    Imao, Tetsuya; Amano, Toshiyasu; Takemae, Katsurou

    2011-02-01

    A 43-year-old woman was referred to our clinic for evaluation of a left retroperitoneal mass. She presented to our internal medicine department complaining of back pain. Computed tomography (CT) scan revealed a left retroperitoneal mass 55 mm in size in the hilum of the left kidney. Enhanced CT scan and magnetic resonance imaging (MRI) disclosed a poorly staining mass. Metaiodobenzylguanidine scintigraphy demonstrated no accumulation in the mass; moreover, endocrinologic examination was normal. Laparoscopic resection of the left retroperitoneal tumor was attempted; however, strong adhesion between the tumor and the left renal vein was encountered. Thus, left nephrectomy after open conversion was performed. Histological findings indicated leiomyosarcoma originating from the left renal vein. The postoperative course has been uneventful; neither recurrence nor metastasis is evident 2 years postsurgery. PMID:20694494

  12. [ENDOVENOUS LASER TREATMENT FOR VARICOSE VEINS].

    PubMed

    Tezuka, Masahiro; Kanaoka, Yuji; Ohki, Takao

    2015-05-01

    Varicose veins are a common condition attecting approximately 10 million patients in Japan. The main cause of varicose veins is reflux of the saphenous vein, and conventional treatment for several decades was stripping the affected saphenous vein and phlebectomy. Endovenous laser treatment (EVLT) is a less-invasive treatment method in which the saphenous vein is ablated with a laser under local anesthesia. EVLT has been approved by the Japanese Ministry of Health, Labor and Welfare since 2011, and we have performed EVLT on 5,160 legs with saphenous insufficiency with no severe complications including deep vein thrombosis except for one case of arteriovenous fistula. EVLT appears to be a safe, effective treatment option for varicose veins with saphenous insufficiency. PMID:26281654

  13. Chiral oily streaks in a smectic-A liquid crystal.

    PubMed

    Nemitz, Ian R; Ferris, Andrew J; Lacaze, Emmanuelle; Rosenblatt, Charles

    2016-08-21

    The liquid crystal octylcyanobiphenyl (8CB) was doped with the chiral agent CB15 and spin-coated onto a substrate treated for planar alignment of the director, resulting in a film of thickness several hundred nm in the smectic-A phase. In both doped and undoped samples, the competing boundary conditions - planar alignment at the substrate and vertical alignment at the free surface - cause the liquid crystal to break into a series of flattened hemicylinders to satisfy the boundary conditions. When viewed under an optical microscope with crossed polarizers, this structure results in a series of dark and light stripes ("oily streaks") of period ∼1 μm. In the absence of chiral dopant the stripes run perpendicular to the substrate's easy axis. However, when doped with chiral CB15 at concentrations up to c = 4 wt%, the stripe orientation rotates by a temperature-dependent angle φ with respect to the c = 0 stripe orientation, where φ increases monotonically with c. φ is largest just below the nematic - smectic-A transition temperature TNA and decreases with decreasing temperature. As the temperature is lowered, φ relaxes to a steady-state orientation close to zero within ∼1 °C of TNA. We suggest that the rotation phenomenon is a manifestation of the surface electroclinic effect: The rotation is due to the weak smectic order parameter and resulting large director tilt susceptibility with respect to the smectic layer normal near TNA, in conjunction with an effective surface electric field due to polar interactions between the liquid crystal and substrate. PMID:27426740

  14. 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.

  15. Dust Devils Seen Streaking Across Mars: PART 1--What Are These?

    NASA Technical Reports Server (NTRS)

    2000-01-01

    PIA02376 [figure removed for brevity, see original site]

    PIA02377 [figure removed for brevity, see original site]

    Dark streaks, everywhere! Many Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images of the middle latitudes of the northern and southern hemispheres of Mars show wild patterns of criss-crossing dark streaks. Many of these streaks are straight and narrow, others exhibit curly arcs, twists, and loops. They often cross over hills, run straight across dunes and ripples, and go through fields of house-sized boulders. The two examples shown above were acquired in the last three months. Both pictures are illuminated by sunlight from the upper left. The first picture (left), showing dark streaks on the rippled flats of Argyre Planitia, covers an area 3 km by 5 km (1.9 by 3.1 miles) at a latitude of 51oS. The second picture (right) shows an area approximately 3 km by 5 km in Promethei Terra at a latitude of 58oS.

    For many months the MOC science team was seeing streaks such as these, but were uncertain how they formed. One speculation was that they might result from the passage of dust devils. Each dust devil would leave a dark streak by removing bright dust from the terrain in its path, revealing a darker surface underneath. An image described by the MOC team in July 1998 showed examples of streaks that were, at the time, speculated to be caused by dust devils.

  16. 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

  17. 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

  18. 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

  19. Ets2-dependent trophoblast signalling is required for gastrulation progression after primitive streak initiation.

    PubMed

    Polydorou, Christiana; Georgiades, Pantelis

    2013-01-01

    Although extraembryonic ectoderm trophoblast signals the embryo for primitive streak initiation, a prerequisite for gastrulation, it is unknown whether it also signals for the progression of gastrulation after primitive streak initiation. Here, using Ets2-/- mice, we show that trophoblast signalling is also required in vivo for primitive streak elongation, completion of intraembryonic mesoderm epithelial-mesenchymal transition and the development of anterior primitive streak derivatives such as the node. We show that Ets2-dependent trophoblast signalling is required for the maintenance of high levels of Nodal and Wnt3 expression in the epiblast and for the induction of Snail expression in the primitive streak, between embryonic day 6.3 and 6.7. Within extraembryonic ectoderm trophoblast, Ets2 maintains the expression of the transcription factors Elf5, Cdx2 and Eomes, and that of the signalling molecule Bmp4. We propose a model that provides a genetic explanation as to how Ets2 in trophoblast mediates the progression of gastrulation within the epiblast. PMID:23552073

  20. Shifts in leaf vein density through accelerated vein formation in C4 Flaveria (Asteraceae)

    PubMed Central

    McKown, Athena D.; Dengler, Nancy G.

    2009-01-01

    Background and Aims Leaf venation in many C4 species is characterized by high vein density, essential in facilitating rapid intercellular diffusion of C4 photosynthetic metabolites between different tissues (mesophyll, bundle sheath). Greater vein density has been hypothesized to be an early step in C4 photosynthesis evolution. Development of C4 vein patterning is thought to occur from either accelerated or prolonged procambium formation, relative to ground tissue development. Methods Cleared and sectioned tissues of phylogenetically basal C3 Flaveria robusta and more derived C4 Flaveria bidentis were compared for vein pattern in mature leaves and vein pattern formation in developing leaves. Key Results In mature leaves, major vein density did not differ between C3 and C4 Flaveria species, whereas minor veins were denser in C4 species than in C3 species. The developmental study showed that both major and minor vein patterning in leaves of C3 and C4 species were initiated at comparable stages (based on leaf length). An additional vein order in the C4 species was observed during initiation of the higher order minor veins compared with the C3 species. In the two species, expansion of bundle sheath and mesophyll cells occurred after vein pattern was complete and xylem differentiation was continuous in minor veins. In addition, mesophyll cells ceased dividing sooner and enlarged less in C4 species than in C3 species. Conclusions Leaf vein pattern characteristic to C4 Flaveria was achieved primarily through accelerated and earlier offset of higher order vein formation, rather than other modifications in the timing of vein pattern formation, as compared with C3 species. Earlier cessation of mesophyll cell division and reduced expansion also contributed to greater vein density in the C4 species. The relatively late expansion of bundle sheath and mesophyll cells shows that vein patterning precedes ground tissue development in C4 species. PMID:19759038

  1. Gold Veins near Great Falls, Maryland

    USGS Publications Warehouse

    Reed, John Calvin, Jr.; Reed, John C.

    1969-01-01

    Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian (?) age. The veins cut granitic rocks of Devonian or pre-Devonian age and may be as young as Triassic. Further development of the deposits is unlikely under present economic conditions because of their generally low gold content and because much of the vein system lies on park property, but study of the Great Falls vein system may be useful in the search for similar deposits elsewhere in the Appalachian Piedmont.

  2. Preduodenal portal vein: its surgical significance.

    PubMed

    Makey, D A; Bowen, J C

    1978-11-01

    Preduodenal portal vein is a rare anatomical variant which may be one of many anomalies in the neonate with duodenal "atresia." Preduodenal portal vein also may be an occasional finding in an adult undergoing biliary, gastric, or pancreatic surgery. Awareness and recognition of the anomaly are essential for the avoidance of injury during such operations. We report here a symptomless patient whose preduodenal portal vein was discovered at cholecystectomy. PMID:715684

  3. Laser leg vein treatment: a brief overview.

    PubMed

    Ross, Victor; Domankevitz, Yacov

    2003-12-01

    Laser treatment of leg veins has been associated with a number of disadvantages, but the introduction of new devices has increased the role of lasers in the treatment of leg veins. This paper reviews the role of laser devices applied from the surface in the treatment of reticular and spider veins. Success is determined by the proper selection of wavelength, fluence, pulse duration, spot size, and number and frequency of treatments. PMID:14741827

  4. Intravitreal ranibizumab for bilateral choroidal neovascularisation in a patient with angioid streaks

    PubMed Central

    Yilmaz, Ihsan; Ozkaya, Abdullah; Alkin, Zeynep; Yazici, Ahmet Taylan

    2014-01-01

    Angioid streaks are described as irregular lines deep into the retina, configured in a radiating fashion which results from breaks in Bruch’s membrane. Optic nerve head drusen are acellular, globular deposits located within the optic nerve head. Angioid streaks and optic nerve head drusen may coexist in patients with pseudoxanthoma elasticum. Both disorders may cause choroidal neovascularisation. In this case report we aimed to present a 48-year-old man with pseudoxanthoma elasticum. The patient had bilateral choroidal neovascularisation secondary to angioid streaks and was treated with intravitreal ranibizumab injections. Visual acuity was increased and maintained at the same level during the follow-up time. There was no complication related to the injection. PMID:25073527

  5. 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.

    1984-01-01

    Higher temporal resolution data from NASA's fourth Atmospheric Variability Experiment (April 24-25, 1975) are used to study the role of diabatic heating within the convective region in altering the ageostrophic mass circulation in the entrance region of the jet streak. The modifying effect this diabatic heating in the mesoscale storm exerts on the synoptic-scale environmental flow through dynamical mechanisms which link the mass circulation of these two scales is examined. The effect of diabatic heating on the ageostrophic motion within the thermally direct circulation of the jet streak and the mesoscale convective complexes is investigated. Diabatic modes of ageostrophic motion that intensify the upper tropospheric jet streak downstream are identified.

  6. Critical evaluation of attosecond time delays retrieved from photoelectron streaking measurements

    NASA Astrophysics Data System (ADS)

    Wei, Hui; Morishita, Toru; Lin, C. D.

    2016-05-01

    A photoelectron streaking experiment which was conceived as a means to extract the electron wave packet of single-photon ionization has also been employed to retrieve time delays in the fundamental photoemission processes. The discrepancies between the time delays thus measured and those from many sophisticated theoretical calculations have generated a great deal of controversy in recent years. Here we present a careful examination of the methods that were used to retrieve the time delays and demonstrate the difficulty of achieving an accuracy of the retrieved time delays of a few to tens of attoseconds in typical streaking measurements. The difficulty owes more to the lower sensitivity of the streaking spectra to the phase of the photoionization transition dipole than to the spectral phase of the attosecond light pulse in the experiment. The retrieved time delay contains extra errors when the attochirp of the attosecond pulse is large so that the dipole phase becomes negligible compared to it.

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

    SciTech Connect

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

    2015-09-15

    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:Al{sub 2}O{sub 3} solid state laser oscillator and also a fiber oscillator.

  8. 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.

  9. Imaging plasmonic fields near gold nanospheres in attosecond time-resolved streaked photoelectron spectra

    NASA Astrophysics Data System (ADS)

    Li, Jianxiong; Thumm, Uwe

    2016-05-01

    To study time-resolved photoemission from gold nanospheres, we introduce a quantum-mechanical approach, including the plasmonic near-field-enhancement of the streaking field at the surface of the nanosphere. We use Mie theory to calculate the plasmonically enhanced fields near 10 to 200 nm gold nanospheres, driven by incident near infrared (NIR) or visible laser pulses. We model the gold conduction band in terms of a spherical square well potential. Our simulated streaked photoelectron spectra reveal a plasmonic amplitude enhancement and phase shift related to calculations that exclude the induced plasmonic field. The phase shift is due to the plasma resonance. This suggests the use of streaked photoelectron spectroscopy for imaging the dielectric response and plasmonic field near nanoparticles. Supported by the NSD-EPSCoR program, NSF, and the USDoE.

  10. 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.

  11. 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.

  12. 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

  13. The adrenal and renal veins of man and their connections with azygos and lumbar veins.

    PubMed

    Monkhouse, W S; Khalique, A

    1986-06-01

    There exist many variations in the manner of formation, dimensions and place of termination of the central adrenal veins. In addition, some superficial adrenal veins may be substantial in size and may themselves drain directly into the renal veins and/or into other vessels which communicate with azygos and lumbar veins. This provides a route for venous adrenal blood to the heart via the azygos system and the superior vena cava rather than via the inferior vena cava. Variations in the formation and disposition of the renal veins are also described and the patterns of communication between somatic veins (including veins of the azygos and lumbar systems) and the left renal vein are illustrated and discussed in relation to the findings of others. PMID:3693053

  14. 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.

  15. 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.

  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. Linear stability of optimal streaks in the log-layer of turbulent channel flows

    NASA Astrophysics Data System (ADS)

    Alizard, Frédéric

    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, Reτ = 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 λz ≈ y/0.3 and a streamwise length of λx ≈ 3λz, 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

  18. What Are the Signs and Symptoms of Varicose Veins?

    MedlinePlus

    ... from the NHLBI on Twitter. What Are the Signs and Symptoms of Varicose Veins? The signs and symptoms of varicose veins include: Large veins ... skin in the area around the varicose vein. Signs of telangiectasias are clusters of red veins that ...

  19. 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...

  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 Virchow’s 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

  1. Isotopic streaks suggest a stripy plume under the Marquesas

    NASA Astrophysics Data System (ADS)

    Chauvel, C.; Blais, S.; Maury, R.; Lewin, E.

    2009-12-01

    underlying the southern and the northern islands is the same. We believe that the stripes are mantle plume characteristics. Their presence and persistent occurrence for the 5 Ma of Marquesas volcanism suggest that isotopically distinct mantle sources cohabitate but do not mix at distances less than 100 km. Furthermore, the isotopic range observed at the island scale is also very large, suggesting melting of extremely heterogeneous plume material. To account for all these observations, as well as the geophysical constraints and the age distribution of the islands, we suggest a model like that of Davaille (Nature, 1999) for general plume structures, and Farnetani and Hofmann (EPSL, 2009) for the internal structure of the Hawaiian plume: several small conduits that originated in a single deep mantle plume bring magma to the surface at different locations at the same time. The material melting in the plume is highly heterogeneous at all scales (10 to 100 km) but because systematic trends occur, an organized pattern must persist through time. The inference is that the heterogeneities in the plume were streaked out vertically and parallel to the direction of plume ascent.

  2. 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...

  3. 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

  4. 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...

  5. 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. ...

  6. 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...

  7. 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....

  8. Numerical analysis of three-dimensional unsteady hot streak migration and shock interaction in a turbine stage

    SciTech Connect

    Saxer, A.P.; Felici, H.M.

    1996-04-01

    A three-dimensional unsteady flow computation has been performed for a transonic first turbine stage under the influence of streaks of hot gas exiting the combustion chamber. Realistic flow conditions are obtained by using an unequal stator-to-rotor pitch, a single-streak/multistator channel configuration, and periodic boundary conditions. The resulting unsteady shock wave system and the hot streak migration as well as the shock wave/streak interaction are presented and discussed. In addition, the time average of the periodic unsteady solution is analyzed and compared with a steady-state computation. The steady-state solution matches the time-averaged one in terms of the pressure field and the maximum stagnation temperature on the rotor blade surface. However, the rotor blade temperature patterns are different with a stronger radial secondary flow present in the time-averaged solution due to the retention of the circumferential streak variations at the stator/rotor interface.

  9. 21 CFR 880.6980 - Vein stabilizer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vein stabilizer. 880.6980 Section 880.6980 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Miscellaneous Devices § 880.6980 Vein stabilizer. (a)...

  10. Who Is at Risk for Varicose Veins?

    MedlinePlus

    ... risk for varicose veins, including family history, older age, gender, pregnancy, overweight or obesity , lack of movement, and leg trauma. Family History Having family members who have varicose veins may ... of them. Older Age Getting older may raise your risk for varicose ...

  11. [Aneurysm of the femoral and popliteal vein].

    PubMed

    Hansen, L G; Boris, P

    1986-04-01

    Aneurysms of the popliteal and femoral veins are rare and may be seen as casual findings with no clinical manifestations whatsoever. On the other hand they may be potential source of recurrent pulmonary embolism. A case is reported, where an aneurysm of the femoral vein was found in a clinically symptomless woman aged 48. PMID:3715020

  12. [Pseudotumor aspect of ovarian vein thrombosis].

    PubMed

    Randoux, B; Goudot, D; Clément, O; Deux, J F; Lecuru, F; Taurelle, R; Frija, G

    1997-11-01

    Ovarian vein thrombosis is an unusual puerperal illness (1 in 600 deliveries) which usually recovers spontaneously or under treatment. We report a rare follow-up observation of a puerperal ovarian vein thrombophlebitis, first diagnosed by computed tomography, which evolved to a 6 x 10 cm pseudotumoral cavernoma mass after 18 months. PMID:9499957

  13. Pancreatic pseudocyst rupture into the portal vein.

    PubMed

    Dawson, Brian C; Kasa, David; Mazer, Mark A

    2009-07-01

    A patient with a pancreatic pseudocyst rupture into the portal vein with a resultant noninfectious systemic inflammatory response syndrome and subsequent portal vein thrombosis diagnosed by computed tomography and ultrasonography is reported. A review of the existing English literature on this rare complication is also provided. PMID:19561436

  14. Recombinant Human Elastase Treatment of Cephalic Veins

    PubMed Central

    Wong, Marco D; Bingham, Karen; Moss, Emma; Warn, J Donald; Smirnov, Igor; Bland, Kimberly S; Starcher, Barry; Franano, F Nicholas; Burke, Steven K

    2016-01-01

    Background Vessel injury at the time of Arteriovenous Fistula (AVF) creation may lead to neointimal hyperplasia that impairs AVF maturation. Vonapanitase, a recombinant human chymotrypsin-like elastase family member 1, is an investigational drug under development to improve AVF maturation and patency. The current studies were designed to document vonapanitase effects in human cephalic veins that are used in AVF creation. Methods Human cephalic veins were mounted on a perfusion myograph. Vonapanitase 1.2, 4, 13.2, and 40 μg/ml or saline was applied drop wise on the vein followed by saline rinse. Vein segments were cut into rings for elastin content determination by desmosine radioimmunoassay and histology. Fluorescently-labelled vonapanitase was applied to veins and adventitial imaging was performed using laser scanning confocal microscopy. In vivo time course experiments were performed by treating rabbit jugular veins and harvesting 1 h and 4 h after vonapanitase treatment. Results / Conclusion Vonapanitase reduced desmosine content in a dose-related manner. Histology also confirmed a dose-related reduction in elastic fiber staining. Fluorescently-labelled vonapanitase persistently localized to elastic fibers in the vein adventitia. In vivo experiments showed a reduction in desmosine content in jugular veins from 1 h to 4 h following treatment. These data suggest that vonapanitase targets elastin in elastic fibers in a dose related manner and that elastase remains in the vessel wall and has catalytic activity for at least 1 h.

  15. Vein graft in stapes surgery.

    PubMed

    Kamal, S A

    1996-03-01

    Sealing the opening of the oval window during stapes surgery is essential; it prevents postoperative complications, such as perilymph fistula and sensorineural hearing loss. In this small series of 269 cases with otosclerosis, tympanosclerosis, and congenital ossicular abnormality, vein grafting was used to seal the opening of the footplate. Hearing improvement after surgery was acceptable, and none had total hearing loss or perilymphatic fistula. World literature from the last half of this century on grafting the oval window is reviewed. Absorbable gelatin sponge (Gelfoam) seems to be causing more complications, so its use is highly discouraged. Temporalis fascia, fat, and perivenous loose areolar tissue have been used by different authors at different times in footplate surgery. The opening created in the oval window during stapes surgery must not be left uncovered. PMID:8723953

  16. Phlebectasia of Internal Jugular Vein

    PubMed Central

    Bindal, Satish K.; Vasisth, Gaurav O. P.; Chibber, Puneet

    2012-01-01

    Internal jugular phlebectasia (IJP) is a rare disease in which there is a fusiform dilatation of internal jugular vein, usually presenting as a neck mass in children. Accurate diagnosis from careful history, physical examination, and radiological study can be made. We report a 12-year-old boy with history of swelling appearing on the right side of the neck only on straining, coughing, or during a Valsalva maneuver. Diagnosis of right IJP was made. Exploration and wrapping the dilated segment in an 8-mm-diameter polytetrafluoroethylene tube graft was done. Because of its rarity, this entity is frequently ignored or misdiagnosed. This case report intends to stress the importance of keeping IJP as differential diagnosis while dealing with such a swelling to avoid invasive investigations and inappropriate treatment. PMID:23741586

  17. Retinal vein occlusion: current treatment.

    PubMed

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management. PMID:20938213

  18. Treatment of deep vein thrombosis

    PubMed Central

    Douketis, James D.

    2005-01-01

    OBJECTIVE To identify patients with deep vein thrombosis (DVT) for whom in-hospital treatment should be considered. QUALITY OF EVIDENCE The literature was searched for studies on outpatient treatment of DVT. Seventeen studies were assessed: seven were randomized controlled trials (level I evidence), and 10 were non-randomized trials (level II evidence). MAIN MESSAGE Four criteria can be used to identify patients with DVT for whom outpatient treatment might not be appropriate: presence of massive DVT, presence of symptomatic pulmonary embolism, high risk of bleeding with anticoagulant therapy, and presence of comorbid conditions or other factors that warrant in-hospital care. CONCLUSION Four criteria can be used to identify patients with DVT for whom in-hospital treatment should be considered. PMID:15751565

  19. 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.

  20. Guide wire migration during femoral vein catheterization.

    PubMed

    Khatami, Mohammad Reza; Abbasi, Rozita; Sadigh, Gelareh

    2010-10-01

    Central vein catheterization is a routine and relatively safe procedure in critically ill patients. Complications with this procedure depend to the site of catheterization and the skill of the operator. In addition to the common complications with femoral vein catheterization there are some rare usually preventable side effects related to guide wire and catheter. In our patient who underwent femoral catheterization for acute hemodialysis, we report migration of guide wire through the systemic circulation from the femoral vein to the jugular vein. This is a very rare complication that is a human error and is totally preventable by doing the procedure by a skilled doctor and considering the standards described for central vein catheter insertion. PMID:20852377

  1. Adventitial cystic disease of common femoral vein

    PubMed Central

    Suh, Bo-Yang

    2011-01-01

    Adventitial cystic disease (ACD) of venous system is an extremely rare condition. Very few reports of ACD in venous system have been described. In this report we discuss two cases of common femoral vein ACD that presented with a swollen leg by the obstruction of the vein. Ultrasound imaging showed the typical hypoechoic fluid filled cyst with a posterior acoustic window. Computed tomography scan and ascending venogram showed a stenosis to flow in the common femoral vein caused by an extrinsic mass. Trans-adventitial evacuation of cyst with removal of vein wall was performed for both cases. During operation we found the gelatinous material in the cysts arising in the wall of the common femoral vein and compressing the lumen. The patients were released after short hospitalization and have remained symptom free with no recurrence. PMID:22066091

  2. Upper extremity deep vein thrombosis

    PubMed Central

    Saseedharan, Sanjith; Bhargava, Sunil

    2012-01-01

    A 56-year-old female, recently (3 months) diagnosed with chronic kidney disease (CKD), on maintenance dialysis through jugular hemodialysis lines with a preexisting nonfunctional mature AV fistula made at diagnosis of CKD, presented to the hospital for a peritoneal dialysis line. The recently inserted indwelling dialysis catheter in left internal jugular vein had no flow on hemodialysis as was the right-sided catheter which was removed a day before insertion of the left-sided line. The left-sided line was removed and a femoral hemodialysis line was cannulated for maintenance hemodialysis, and the next day, a peritoneal catheter was inserted in the operation theater. However, 3 days later, there was progressive painful swelling of the left hand and redness with minimal numbness. The radial artery pulsations were felt. There was also massive edema of forearm, arm and shoulder region on the left side. Doppler indicated a steal phenomena due to a hyperfunctioning AV fistula for which a fistula closure was done. Absence of relief of edema prompted a further computed tomography (CT) angiogram (since it was not possible to evaluate the more proximal venous segments due to edema and presence of clavicle). Ct angiogram revealed central vein thrombosis for which catheter-directed thrombolysis and venoplasty was done resulting in complete resolution of signs and symptoms. Upper extremity DVT (UEDVT) is a very less studied topic as compared to lower extremity DVT and the diagnostic and therapeutic modalities still have substantial areas that need to be studied. We present a review of the present literature including incidences, diagnostic and therapeutic modalities for this entity. Data Sources: MEDLINE, MICROMEDEX, The Cochrane database of Systematic Reviews from 1950 through March 2011. PMID:22624098

  3. 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 vein thrombosis ( ... serious, possibly life-threatening problems if not treated. Deep Vein Thrombosis Only about half of the people who have ...

  4. [SUBFASCIAL ENDOSCOPIC PERFORATOR VEIN SURGERY IN THE TREATMENT OF SEVERE VARICOSE VEINS].

    PubMed

    Tabuchi, Atsushi; Masaki, Hisao; Tanemoto, Kazuo

    2015-05-01

    Surgical treatment of severe varicose veins (CEAP classification : C4b-C6) should involve not only interruption of incompetent superficial veins to prevent venous regurgitation due to valve incompetence but also interruption of incompetent perforator veins. Subfascial endoscopic perforator vein surgery (SEPS) is performed via a small skin incision and involves interruption of perforator veins by the insertion of an endoscope into the subfascial space. SEPS produces good surgical outcomes: it is accurate in detecting and transecting perforator veins; has a low frequency of surgical wound complications; prevents lipodermatosclerosis and formation of pigmented skin lesions; and is minimally invasive compared with Linton's operation. Thus, SEPS is an excellent procedure for patients with incompetent perforator veins. SEPS has been covered by the Japanese national health insurance system since April 2014, and it is expected that SEPS will be further developed and become more widespread in use. PMID:26281656

  5. Role of wheat streak mosaic virus-encoded proteins in disease development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eriophyid mite-transmitted wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are the type species of Tritimovirus and Poacevirus genera, respectively, in the family Potyviridae. TriMV and WSMV exhibit differential symptom phenotypes on wheat: TriMV elicits mild mosaic and mottling ...

  6. 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...

  7. 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...

  8. 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...

  9. 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.

  10. 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...

  11. Chromatin Structure of Wheat Breeding Lines Resistant to Wheat Streak Mosaic Virus.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat Streak Mosaic Virus (WSMV) is an important disease limiting wheat production, however no WSMV resistance effective above 18°C is present within the primary genetic pool of wheat (Triticum aestivum L.). In contrast, the wild relative Thinopyrum intermedium (2n=6x=42) shows good resistance to WS...

  12. Physiological responses of hard red winter wheat to infection by wheat streak mosaic virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) causes significant yield loss in hard red winter wheat in the U.S. Southern High Plains. Despite the prevalence of this pathogen, little is known about the physiological response of wheat to WSMV infection. A 2-year study was initiated to (i) investigate the effect o...

  13. 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...

  14. 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...

  15. 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...

  16. 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. PMID:26933280

  17. 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.

  18. 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

  19. Diverse soybean accessions identified with temperature-sensitive resistance to Tobacco streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tobacco streak virus (TSV) is a pathogen that has been reported in soybean in Brazil and the United States, for which resistance has only been reported in the “hay-type” soybean cultivar Tanner. To find additional resistant soybean genotypes, over 1000 soybean accessions from the USDA Soybean Germpl...

  20. The umbilical and paraumbilical veins of man.

    PubMed Central

    Martin, B F; Tudor, R G

    1980-01-01

    During its transit through the umbilicus structural changes occur in the thick wall of the extra-abdominal segment of the umbilical vein whereby the components of the intra-abdominal segment acquire an essentially longitudinal direction and become arranged in fibro-elastic and fibro-muscular zones. The vein lumen becomes largely obliterated by asymmetrical proliferation of loose subendothelial conective tissue. The latter forms a new inner zone within which a small segment of the lumen persists in an eccentric position. This residual lumen transmits blood to the portal system from paraumbilical and systemic sources, and is retained in the upper part of the vein, even in old age. A similar process of lumen closure is observed in the ductus venosus. In early childhood the lower third of the vein undergoes breakdown, with fatty infiltration, resulting in its complete division into vascular fibro-elastic strands, and in old age some breakdown occurs in the outermost part of the wall of the upper two thirds. The paraumbilical veins are thick-walled and of similar structure to the umbilical vein. Together they constitute an accessory portal system which is confined between the layers of the falciform ligament and is in communication with the veins of the ventral abdominal wall. The constituents form an ascending series, namely, Burow's veins, the umbilical vein, and Sappey's inferior and superior veins. The main channel of Sappey's inferior veins may be the remnant of the right umbilical vein since it communicates with the right rectus sheath and often communicates directly with the portal system within the right lobe of the liver. The results are of significance in relation to clinical usage of the umbilical vein. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 21 Fig. 22 Fig. 23 Fig. 24 Fig. 25 Fig. 26 Fig. 27 Fig. 28 Fig. 29 PMID:7400038

  1. 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

  2. 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

  3. Personal authentication through dorsal hand vein patterns

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Bin; Hao, Shu-Sheng; Lee, Jen-Chun

    2011-08-01

    Biometric identification is an emerging technology that can solve security problems in our networked society. A reliable and robust personal verification approach using dorsal hand vein patterns is proposed in this paper. The characteristic of the approach needs less computational and memory requirements and has a higher recognition accuracy. In our work, the near-infrared charge-coupled device (CCD) camera is adopted as an input device for capturing dorsal hand vein images, it has the advantages of the low-cost and noncontact imaging. In the proposed approach, two finger-peaks are automatically selected as the datum points to define the region of interest (ROI) in the dorsal hand vein images. The modified two-directional two-dimensional principal component analysis, which performs an alternate two-dimensional PCA (2DPCA) in the column direction of images in the 2DPCA subspace, is proposed to exploit the correlation of vein features inside the ROI between images. The major advantage of the proposed method is that it requires fewer coefficients for efficient dorsal hand vein image representation and recognition. The experimental results on our large dorsal hand vein database show that the presented schema achieves promising performance (false reject rate: 0.97% and false acceptance rate: 0.05%) and is feasible for dorsal hand vein recognition.

  4. Yellow nails following hemodialysis in chronic renal failure: is it yellow nail syndrome or a variant?

    PubMed

    Mehta, Vandana; Vasanth, Vani; Balachandran, C

    2008-01-01

    Yellow nail syndrome (YNS) is triad of yellow nails, lymphedema, and respiratory tract involvement. The exact pathogenesis of nail changes in YNS is unknown. We present a case of yellow nails and localized lymphedema secondary to artificial AV fistula in a 55-year-old chronic renal failure patient on hemodialysis for 5 years. To the best of our knowledge, this is the first case of yellow nail syndrome reported in association with artificial AV fistula. PMID:19094857

  5. 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...

  6. 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...

  7. 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.

  8. Echocardiographic diagnosis of pulmonary vein varix.

    PubMed

    Shiraishi, Jun; Tatsumi, Tetsuya; Kimata, Masaki; Kambayashi, Daisuke; Mano, Akiko; Yamanaka, Satoshi; Kobara, Miyuki; Azuma, Akihiro; Nakagawa, Masao

    2003-09-01

    Pulmonary vein varix is a rare abnormality, often resembling a pulmonary or mediastinal mass on chest radiographs, and pulmonary angiography has been the mainstay of diagnosis. An unusual case of pulmonary vein varix was clearly defined by echocardiography performed in a 47-year-old woman with chest discomfort who had been found to have an abnormal structure behind the cardiac silhouette on a chest radiograph. The diagnosis of left lower pulmonary vein varix was noninvasively confirmed by transthoracic echocardiography and transesophageal echocardiography. PMID:12939558

  9. [Endovenous ablation of saphenous vein varicosis].

    PubMed

    Schuller-Petrovic, Sanja

    2016-06-01

    In the past 15 years, the minimally invasive endovenous treatments of varicose veins have been widely accepted. The efficacy of the different endovenous methods and the minimal post operative side effects are meanwhile well documented in a large number of evidence based publications. The recent NICE Guidelines (2013) considering the varicose vein treatment recommend in case of an insufficiency of saphenous veins first the endovenous thermal ablation with radiofrequency or laser, then the ultrasound guided sclerotherapy and as the third line the classic surgical treatment with stripping and high ligation. PMID:27295103

  10. [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

  11. Retinal vein occlusion: pathophysiology and treatment options

    PubMed Central

    Karia, Niral

    2010-01-01

    This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms. PMID:20689798

  12. Complications of umbilical vein catherisation. Case Report

    PubMed Central

    Bothur-Nowacka, Joanna; Czech-Kowalska, Justyna; Gruszfeld, Dariusz; Nowakowska-Rysz, Monika; Kościesza, Andrzej; Polnik, Dariusz; Dobrzańska, Anna

    2011-01-01

    Summary Background: Umbilical vein catheterization is a relatively easy procedure performed routinely on the neonate intensive care units. It provides a fast central vein access, but some complications have been described in the literature. Case Reports: We presented a case report of a premature infant (34 hbd) with extravasation of the parenteral nutrition and drugs to the liver after umbilical vein catheterization. Fever and increasing biochemical markers of infection were observed. USG revealed a heterogenic, well-limited space of 4 cm in diameter, located in the right lobe of the liver. CT excluded liver abscess. Considering neoplastic process or incorrect location of the catheter of the central vein, we performed liver biopsy. Results: Cytological and biochemical analysis of the aspirated fluid revealed extravasation of parenteral nutrition to the liver. Our case confirms the necessity of controlling a proper location of the central catheter right after its insertion and during hospitalization. PMID:22802847

  13. Control strategies for yellow nutsedge and nightshade

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow nutsedge is a perennial weed that is difficult to control in several crops once established. It is particularly problematic in onion production. Yellow nutsedge reproduces and is dispersed primarily by tubers that are formed at the apical ends of underground rhizomes. Tubers may remain viable...

  14. Yellow Fever Outbreak, Southern Sudan, 2003

    PubMed Central

    Onyango, Clayton O.; Grobbelaar, Antoinette A.; Gibson, Georgina V.F.; Sang, Rosemary C.; Sow, Abdourahmane; Swanepoel, Robert

    2004-01-01

    In May 2003, an outbreak of fatal hemorrhagic fever, caused by yellow fever virus, occurred in southern Sudan. Phylogenetic analysis showed that the virus belonged to the East African genotype, which supports the contention that yellow fever is endemic in East Africa with the potential to cause large outbreaks in humans. PMID:15498174

  15. History of Epidemiological Aspects of Yellow Fever

    PubMed Central

    Downs, Wilbur G.

    1982-01-01

    This review attempts to follow the trail of the development of epidemiological aspects and concepts of yellow fever and yellow fever transmission (vectors, vertebrate hosts, spacing of epidemic outbreaks) with less emphasis on well-documented early history and more emphasis on epidemiological problems still remaining, plus discussion of possible means of resolving certain of these problems. PMID:6758368

  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. 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

  18. The role of splenomesenteric vein anastomosis after division of the splenic vein in pancreatoduodenectomy.

    PubMed

    Misuta, Koichiro; Shimada, Hiroshi; Miura, Yasuhiko; Kunihiro, Osamu; Kubota, Toru; Endo, Itaru; Sekido, Hitoshi; Togo, Shinji

    2005-02-01

    Division of the splenic vein was performed in 29 patients who underwent pancreatoduodenectomy to achieve lymph node dissection and neural resection around the superior mesenteric artery. The basic protocol for the splenic vein reconstruction to reduce congestion of the spleen and stomach is as follows. When the inferior mesenteric vein (IMV) drained into the splenic vein, the confluence was preserved without reconstruction of the splenic vein. When the IMV drained into the superior mesenteric vein (SMV) or the splenomesenteric angle, the division of the IMV and spleno-IMV anastomosis were performed. In postoperative venography, nine patients showed downward flow (from the splenic vein to the IMV) and three patients showed upward flow (from the IMV to the splenic vein). Postoperative computed tomography scans showed venous dilatation and splenomegaly in the upward flow group; there were no patients in the downward flow group. In selected patients, splenic vein reconstruction is necessary to reduce congestion of the spleen and stomach. When the flow is downward, spleno-IMV flow should be preserved. When the flow is upward, spleno-SMV anastomosis is necessary instead of spleno-IMV anastomosis. PMID:15694821

  19. Posttraumatic arteriovenous fistula and subclavian vein thrombosis: treatment by percutaneous arterial embolization and vein angioplasty.

    PubMed

    Gobin, Y P; Soulez, G; Riadh, A; Houdart, E; Herbreteau, D; Merland, J J

    1993-09-01

    A 71-year-old woman had edema and venous dilatation of her upper right limb that caused painful functional disability following a shoulder injury. Arteriograms demonstrated an arteriovenous fistula between the subclavian artery and vein associated with thrombosis of the vein at the same level. The arteriovenous fistula was found to have multiple arteriovenous communications. Because of associated distal venous thrombosis, venous drainage was retrograde through the brachial vein. The inflow arteries of the fistula were embolized and then the subclavian vein thrombosis was recanalized, dilated, and an endoluminal stent inserted. Clinical signs completely resolved. PMID:8268095

  20. Veins improve fracture toughness of insect wings.

    PubMed

    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

  1. 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

  2. Scattering removal for finger-vein image restoration.

    PubMed

    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

  3. Optical streak camera images of wire-array z-pinches on the 1-MA COBRA pulsed power generator

    NASA Astrophysics Data System (ADS)

    McBride, Ryan; Pikuz, Sergei; Blesener, Isaac; Zhao, Yu Tao; Greenly, John; Hammer, David; Kusse, Bruce

    2006-10-01

    Initial optical streak camera imaging experiments of wire array z-pinches on the 1 MA COBRA pulsed power generator are presented. The imaging system makes use of a Hamamatsu C7700 streak unit, which is coupled to a V7669-06 image intensifier with an MCP, and a C4742-98 CCD camera. A long focal length optical system is employed to relay the z-pinch produced light from the experiment chamber to the input slit of the streak camera -- a total transmission distance of approximately 14 m. The optical streak camera images produced, along with data from other supporting diagnostics, are presented for z-pinch implosions of various wire array geometries and materials.

  4. Initial tests of the dual-sweep streak camera system planned for APS particle-beam diagnostics

    SciTech Connect

    Lumpkin, A.; Yang, B.; Gai, W.; Cieslik, W.

    1995-07-01

    Initial tests of a dual-sweep streak system planned for use on the Advanced Photon Source (APS) have been performed using assets of the Argonne Wakefield Accelerator (AWA) facility. The short light pulses from the photoelectric injector drive laser in both the visible ({lambda}=496 nm, {Delta}t{approximately}1.5 ps (FWHM)), and the ultraviolet ({lambda}=248 nm, {Delta}t{approximately}5 ps (FWHM)) were used. Both a UV-visible S20 photocathode streak tube and a UV-to-x-ray Au photocathode streak tube were tested. Calibration data with an etalon were also obtained. A sample of dual-sweep streak data using optical synchrotron radiation on the APS injector synchrotron is also presented.

  5. 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.

  6. 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.

  7. A distinct tospovirus causing necrotic streak on Alstroemeria sp. in Colombia.

    PubMed

    Hassani-Mehraban, Afshin; Botermans, Marleen; Verhoeven, J Th J; Meekes, Ellis; Saaijer, Janneke; Peters, Dick; Goldbach, Rob; Kormelink, Richard

    2010-03-01

    A tospovirus causing necrotic streaks on leaves was isolated from Alstroemeria sp. in Colombia. Infected samples reacted positively with tomato spotted wilt virus (TSWV) antiserum during preliminary serological tests. Further analysis revealed a close serological relationship to tomato chlorotic spot virus (TCSV) and groundnut ringspot virus (GRSV). A major part of the S-RNA segment, encompassing the nucleocapsid (N) protein gene, the 5' untranslated region and a part of the intergenic region 3' of the N gene, was cloned and sequenced. The deduced N protein sequence showed highest amino acid identity (82%) to that of TCSV, indicating that the virus represents a new tospovirus species, for which the name Alstroemeria necrotic streak virus (ANSV) is coined. Phylogenetic analysis based on the N protein sequence revealed that this Alstroemeria-infecting tospovirus clustered with tospoviruses from the American continent. Frankliniella occidentalis was identified as potential vector species for ANSV. PMID:20151164

  8. 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 Czerny–Turner, 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.

  9. Time-resolved spectra of dense plasma focus using spectrometer, streak camera, and CCD combination

    SciTech Connect

    Goldin, F. J.; Meehan, B. T.; Hagen, E. C.; Wilkins, P. R.

    2010-10-15

    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 Czerny-Turner, 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.

  10. Protocol for observing molecular dipole excitations by attosecond self-streaking

    NASA Astrophysics Data System (ADS)

    Wachter, Georg; Nagele, Stefan; Sato, Shunsuke A.; Pazourek, Renate; Wais, Michael; Lemell, Christoph; Tong, Xiao-Min; Yabana, Kazuhiro; Burgdörfer, Joachim

    2015-12-01

    We propose a protocol to probe the ultrafast evolution and dephasing of coherent electronic excitation in molecules in the time domain by the intrinsic streaking field generated by the molecule itself. Coherent electronic motion in the endohedral fullerene Ne@C 60 is initiated by a moderately intense femtosecond UV-visible pulse leading to coherent oscillations of the molecular dipole moment that persist after the end of the laser pulse. The resulting time-dependent molecular near field is probed through the momentum modulation of photoemission from the central neon atom by a time-delayed attosecond XUV pulse. Our ab initio time-dependent density functional theory and classical trajectory simulations predict that this self-streaking signal accurately traces the molecular dipole oscillations in real time. We discuss the underlying processes and give an analytical model that captures the essence of our ab initio simulations.

  11. Extra-embryonic Wnt3 regulates the establishment of the primitive streak in mice

    PubMed Central

    Yoon, Yeonsoo; Huang, Tingting; Tortelote, Giovane G.; Wakamiya, Maki; Hadjantonakis, Anna-Katerina; Behringer, Richard R.; Rivera-Pérez, Jaime A.

    2015-01-01

    The establishment of the head to tail axis at early stages of development is a fundamental aspect of vertebrate embryogenesis. In mice, experimental embryology, genetics and expression studies have suggested that the visceral endoderm, an extra-embryonic tissue, plays an important role in anteroposterior axial development. Here we show that absence of Wnt3 in the posterior visceral endoderm leads to delayed formation of the primitive streak and that interplay between anterior and posterior visceral endoderm restricts the position of the primitive streak. Embryos lacking Wnt3 in the visceral endoderm, however, appear normal by E9.5. Our results suggest a model for axial development in which multiple signals are required for anteroposterior axial development in mammals. PMID:25907228

  12. Recording the synchrotron radiation by a picosecond streak camera for bunch diagnostics in cyclic accelerators

    NASA Astrophysics Data System (ADS)

    Vereshchagin, A. K.; Vorob'ev, N. S.; Gornostaev, P. B.; Dorokhov, V. L.; Kryukov, S. S.; Lozovoi, V. I.; Meshkov, O. I.; Nikiforov, D. A.; Smirnov, A. V.; Shashkov, E. V.; Schelev, M. Ya

    2016-02-01

    A PS-1/S1 picosecond streak camera with a linear sweep is used to measure temporal characteristics of synchrotron radiation pulses on a damping ring (DR) at the Budker Institute of Nuclear Physics (BINP) of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk). The data obtained allow a conclusion as to the formation processes of electron bunches and their 'quality' in the DR after injection from the linear accelerator. The expediency of employing the streak camera as a part of an optical diagnostic accelerator complex for adjusting the injection from a linear accelerator is shown. Discussed is the issue of designing a new-generation dissector with a time resolution up to a few picoseconds, which would allow implementation of a continuous bunch monitoring in the DR during mutual work with the electron-positron colliders at the BINP.

  13. Route to One Atomic Unit of Time: Development of a Broadband Attosecond Streak Camera

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Zhang, Qi; Chini, Michael; Chang, Zenghu

    A new attosecond streak camera based on a three-meter-long magnetic-bottle time-of-flight electron spectrometer (MBES) is developed. The temporal resolution of the photoelectron detection system is measured to be better than 250 ps, which is sufficient to achieve an energy resolution of 0.5 eV at 150 eV photoelectron energy. In preliminary experiments, a 94-as isolated XUV pulse was generated and characterized. With a new algorithm to retrieve the amplitude and phase of XUV pulses (PROOF—phase retrieval by omega oscillation filtering), the attosecond streak camera will be able to characterize isolated attosecond pulses as short as one atomic unit of time (25 as).

  14. 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

  15. Temporal resolution limit estimation of x-ray streak cameras using a CsI photocathode

    SciTech Connect

    Li, Xiang; Gu, Li; Zong, Fangke; Zhang, Jingjin; Yang, Qinlao

    2015-08-28

    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.

  16. 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.

  17. 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.

  18. Experimental therapies for yellow fever.

    PubMed

    Julander, Justin G

    2013-02-01

    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

  19. [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

  20. High-Speed Observer: Automated Streak Detection for the Aerospike Engine

    NASA Technical Reports Server (NTRS)

    Rieckhoff, T. J.; Covan, M. A.; OFarrell, J. M.

    2001-01-01

    A high-frame-rate digital video camera, installed on test stands at Stennis Space Center (SSC), has been used to capture images of the aerospike engine plume during test. These plume images are processed in real time to detect and differentiate anomalous plume events. Results indicate that the High-Speed Observer (HSO) system can detect anomalous plume streaking events that are indicative of aerospike engine malfunction.

  1. Complete genome sequence of an emerging genotype of tobacco streak virus in the United States.

    PubMed

    Padmanabhan, Chellappan; Gao, Shan; Li, Rugang; Zhang, Shouan; Fei, Zhangjun; Ling, Kai-Shu

    2014-01-01

    We report here the complete genome sequence of an emerging genotype of tobacco streak virus (TSV) infecting zucchini squash in Florida (TSV_FL13-07), obtained using deep sequencing of short RNAs (sRNAs) and validation by Sanger sequencing. TSV_FL13-07 shares only <90% sequence identity in all three genomic RNAs to several known U.S. isolates. PMID:25377714

  2. Molecular organization of the cholesteryl ester droplets in the fatty streaks of human aorta.

    PubMed Central

    Engelman, D M; Hillman, G M

    1976-01-01

    X-ray diffraction patterns from human arterial specimens containing atherosclerotic fatty streak lesions exhibited a single sharp reflection, corresponding to a structural spacing of about 35 A. Specimens without lesions did not. When specimens with fatty streaks were heated, an order-to-disorder phase transition was revealed by the disappearance of the sharp reflection. The transition was thermally reversible and its temperature varied from aorta to aorta over a range from 28 degrees to 42 degrees C. Since cholesteryl ester droplets are a major component of fatty streaks, comparison studies were made of the diffraction behavior from pure cholesteryl esters. We found that the diffraction patterns of the fatty streak material could be accounted for by the organization of the cholesteryl esters into a liquid-crystalline smectic phase that melts from the smectic to a less ordered phase upon heating. When combined with the conclusions of others from polarized light microscopy, our study shows that a droplet in the smectic phase has well-defined concentric layers of lipid molecules. In each layer, the long axes of the molecules have a net radial orientation with respect to the droplet, but the side-to-side organization is disordered. We suggest that the accessibility of portions of the lipids for specific binding to enzymes or transport proteins may be restricted when they are in the smectic state, and that exchange of lipids with surrounding membranes or other potential binding sites may likewise be inhibited. The restriction in the smectic phase should be greater than in the less ordered phases that exist at higher temperatures. Images PMID:965500

  3. 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

  4. 2-ps Hard X-Ray Streak Camera Measurements at Sector 7 Beamline of the Advanced Photon Source

    SciTech Connect

    Chollet, M.; Ahr, B.; Walko, D.A.; Rose-Petruck, C.; Adams, B.

    2011-08-02

    A hard X-ray streak camera capable of 2-ps time resolution is in operation at the Sector 7 beamline of the Advanced Photon Source. It is used for laser-pump, X-ray probe experiments using the Ti:Sapphire femtosecond laser system installed on the beamline. This streak camera, combined with standardized and prealigned experimental setups, can perform time-resolved liquid-phase absorption spectroscopy, reflectivity, and diffraction experiments.

  5. RNAi-mediated resistance to Cassava brown streak Uganda virus in transgenic cassava.

    PubMed

    Yadav, Jitender S; Ogwok, Emmanuel; Wagaba, Henry; Patil, Basavaprabhu L; Bagewadi, Basavaraj; Alicai, Titus; Gaitan-Solis, Eliana; Taylor, Nigel J; Fauquet, Claude M

    2011-09-01

    Cassava brown streak disease (CBSD), caused by Cassava brown streak Uganda virus (CBSUV) and Cassava brown streak virus (CBSV), is of new epidemic importance to cassava (Manihot esculenta Crantz) production in East Africa, and an emerging threat to the crop in Central and West Africa. This study demonstrates that at least one of these two ipomoviruses, CBSUV, can be efficiently controlled using RNA interference (RNAi) technology in cassava. An RNAi construct targeting the near full-length coat protein (FL-CP) of CBSUV was expressed constitutively as a hairpin construct in cassava. Transgenic cassava lines expressing small interfering RNAs (siRNAs) against this sequence showed 100% resistance to CBSUV across replicated graft inoculation experiments. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed the presence of CBSUV in leaves and some tuberous roots from challenged controls, but not in the same tissues from transgenic plants. This is the first demonstration of RNAi-mediated resistance to the ipomovirus CBSUV in cassava. PMID:21726367

  6. Development of intelligent control system for X-ray streak camera in diagnostic instrument manipulator

    NASA Astrophysics Data System (ADS)

    Pei, Chengquan; Wu, Shengli; Tian, Jinshou; Liu, Zhen; Fang, Yuman; Gao, Guilong; Liang, Lingliang; Wen, Wenlong

    2015-11-01

    An intelligent control system for an X ray streak camera in a diagnostic instrument manipulator (DIM) is proposed and implemented, which can control time delay, electric focusing, image gain adjustment, switch of sweep voltage, acquiring environment parameters etc. The system consists of 16 A/D converters and 16 D/A converters, a 32-channel general purpose input/output (GPIO) and two sensors. An isolated DC/DC converter with multi-outputs and a single mode fiber were adopted to reduce the interference generated by the common ground among the A/D, D/A and I/O. The software was designed using graphical programming language and can remotely access the corresponding instrument from a website. The entire intelligent control system can acquire the desirable data at a speed of 30 Mb/s and store it for later analysis. The intelligent system was implemented on a streak camera in a DIM and it shows a temporal resolution of 11.25 ps, spatial distortion of less than 10% and dynamic range of 279:1. The intelligent control system has been successfully used in a streak camera to verify the synchronization of multi-channel laser on the Inertial Confinement Fusion Facility.

  7. High-Throughput Single-Cell Cultivation on Microfluidic Streak Plates.

    PubMed

    Jiang, Cheng-Ying; Dong, Libing; Zhao, Jian-Kang; Hu, Xiaofang; Shen, Chaohua; Qiao, Yuxin; Zhang, Xinyue; Wang, Yapei; Ismagilov, Rustem F; Liu, Shuang-Jiang; Du, Wenbin

    2016-04-01

    This paper describes the microfluidic streak plate (MSP), a facile method for high-throughput microbial cell separation and cultivation in nanoliter sessile droplets. The MSP method builds upon the conventional streak plate technique by using microfluidic devices to generate nanoliter droplets that can be streaked manually or robotically onto petri dishes prefilled with carrier oil for cultivation of single cells. In addition, chemical gradients could be encoded in the droplet array for comprehensive dose-response analysis. The MSP method was validated by using single-cell isolation of Escherichia coli and antimicrobial susceptibility testing of Pseudomonas aeruginosa PAO1. The robustness of the MSP work flow was demonstrated by cultivating a soil community that degrades polycyclic aromatic hydrocarbons. Cultivation in droplets enabled detection of the richest species diversity with better coverage of rare species. Moreover, isolation and cultivation of bacterial strains by MSP led to the discovery of several species with high degradation efficiency, including four Mycobacterium isolates and a previously unknown fluoranthene-degrading Blastococcus species. PMID:26850294

  8. Attosecond streaking of molecules in the low-energy region studied by a wavefunction splitting scheme

    NASA Astrophysics Data System (ADS)

    Hou, Xue-Feng; Peng, Liang-You; Ning, Qi-Cheng; Gong, Qihuang

    2012-04-01

    We present a theoretical study of the low-energy photoelectron spectra of hydrogen molecular ion generated by a single attosecond pulse in the presence of an infrared (IR) laser field. In order to investigate this type of attosecond streaking of molecules, we developed a very efficient grid-based numerical method to solve the two-centre time-dependent Schrödinger equation (TDSE) in the prolate spheroidal coordinates. Specifically, the radial coordinate is discretized with the finite-element discrete variable representation (FE-DVR) for easy parallel computation and the angular coordinate with the usual DVR. A wavefunction splitting scheme is utilized to reduce the demanding requirement of the computational resource to solve the corresponding TDSE when an IR field is present. After verification of the accuracy and efficiency of our method, we then apply it to investigate the attosecond streaking spectra of H+2 in the low-energy region. In contrast to the usual attosecond streaking in the high-energy region, part of the low-energy electrons may be driven back to rescatter with the residual two-centre core. Very interesting interference structures are present in the low-energy region. When the internuclear distance is small, they are very similar to what we have recently observed in the atomic case.

  9. Optical fiducial timing system for X-ray streak cameras with aluminum coated optical fiber ends

    DOEpatents

    Nilson, David G.; Campbell, E. Michael; MacGowan, Brian J.; Medecki, Hector

    1988-01-01

    An optical fiducial timing system is provided for use with interdependent groups of X-ray streak cameras (18). The aluminum coated (80) ends of optical fibers (78) are positioned with the photocathodes (20, 60, 70) of the X-ray streak cameras (18). The other ends of the optical fibers (78) are placed together in a bundled array (90). A fiducial optical signal (96), that is comprised of 2.omega. or 1.omega. laser light, after introduction to the bundled array (90), travels to the aluminum coated (82) optical fiber ends and ejects quantities of electrons (84) that are recorded on the data recording media (52) of the X-ray streak cameras (18). Since both 2.omega. and 1.omega. laser light can travel long distances in optical fiber with only a slight attenuation, the initial arial power density of the fiducial optical signal (96) is well below the damage threshold of the fused silica or other material that comprises the optical fibers (78, 90). Thus the fiducial timing system can be repeatably used over long durations of time.

  10. Altitude Starting Characteristics of an Afterburner with Autoignition and Hot-streak Ignition

    NASA Technical Reports Server (NTRS)

    Renas, P E; Jansen, E T; Harvey, R W , Sr

    1953-01-01

    An investigation was conducted in an altitude test chamber at the NACA Lewis Laboratory to determine the altitude starting characteristics of an afterburner with autoignition and with hot-streak ignition. Transient afterburner ignition data were obtained over a range of altitudes from 30,000 to 50,000 feet at a flight Mach number of 0.60. Afterburner ignition with a torch igniter located axially at approximately the midpoint of the combustion chamber was possible over the entire range, but ignition ignition with a torch igniter located in the transition section 1 5/8 inches upstream of the turbine stators proved unsatisfactory at an altitude of 50,000 feet due to the inability to obtain flame through the turbine. Increasing the afterburner-inlet total pressure at a constant afterburner fuel-air ratio decreased the afterburner ignition time. Hot-streak ignition was possible within 2 seconds after the time required to obtain the preset, normal afterburner fuel pressure, whereas autoignition required 4 to 7 seconds for the range of altitudes investigated. Following the ignition there was a period of oscillatory operation existing in the engine-afterburner before steady-state operation was attained. The time required for steady-state stable operation decreased as afterburner inlet total pressure increased. The duration of oscillations also decreased with hot-streak ignition because the fuel-air mixture was ignited before a large volume of combustible mixture was accumulated in the afterburner.

  11. Artificial microRNA-derived resistance to Cassava brown streak disease

    PubMed Central

    Wagaba, Henry; Patil, Basavaprabhu L.; Mukasa, Settumba; Alicai, Titus; Fauquet, Claude M.; Taylor, Nigel J.

    2016-01-01

    Artificial miRNAs (amiRNA) were generated targeting conserved sequences within the genomes of the two causal agents of Cassava brown streak disease (CBSD): Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Transient expression studies on ten amiRNAs targeting 21 nt conserved sequences of P1(CBSV and UCBSV), P3(CBSV and UCBSV), CI(UCBSV), NIb(CBSV and UCBSV), CP(UCBSV) and the un-translated region (3′-UTR) were tested in Nicotiana benthamiana. Four out of the ten amiRNAs expressed the corresponding amiRNA at high levels. Transgenic N. benthamiana plants were developed for the four amiRNAs targeting the P1 and NIb genes of CBSV and the P1 and CP genes of UCBSV and shown to accumulate miRNA products. Transgenic plants challenged with CBSV and UCBSV isolates showed resistance levels that ranged between ∼20–60% against CBSV and UCBSV and correlated with expression levels of the transgenically derived miRNAs. MicroRNAs targeting P1 and NIb of CBSV showed protection against CBSV and UCBSV, while amiRNAs targeting the P1 and CP of UCBSV showed protection against UCBSV but were less efficient against CBSV. These results indicate a potential application of amiRNAs for engineering resistance to CBSD-causing viruses in cassava. PMID:26912232

  12. Unsteady numerical simulation of hot streak/blades interaction and film cooling

    NASA Astrophysics Data System (ADS)

    Yi, Weilin; Ji, Lucheng; Xiao, Yunhan

    2010-10-01

    Deeply research on management and application of hot streak is an important way to breakthrough technique obstacle of aero engine hot components. Numerical method is a useful instrument to investigate the correlative problems. Firstly the paper developed independently three dimensional unsteady parallel computational code-MpiTurbo based on Fortran 90 and MPI at Linux operating system. Then unsteady numerical simulation was carried out to investigate impacts of the factors, which included circumferential locations of hot streak and clocking positions of blade rows, on the thermal environment of a 1+1 counter-rotating turbine. The results clearly indicated that clocking positions of hot streak/blade row and blade row/blade row had great influence on the time-averaged temperature distribution of the third blade row. Therefore, it can be effective for improving thermal environment of turbine to optimize blade parameters and clocking positions. Lastly film cooling layout was designed by the repetitious steady simulation based on source term method. And the flow structure detail was given by the unsteady simulation.

  13. A possible scenario for the evolution of Banana streak virus in banana.

    PubMed

    Iskra-Caruana, Marie-Line; Chabannes, Matthieu; Duroy, Pierre-Olivier; Muller, Emmanuelle

    2014-06-24

    Outbreaks of Banana streak virus (BSV) have been recorded worldwide where Musa spp. is grown during the last 20 years with no convincing evidence of epidemics. Epidemics were previously reported in Uganda where BSV is currently endemic. BSV is a plant pararetrovirus of the family Caulimoviridae, genus Badnavirus it causes chlorosis leaf streak disease. The information currently available on banana streak disease makes it possible to identify a complex of distinct BSV species each causing the same disease. BSV exists in two states: one as an episomal form, infecting plant cells; the other as viral DNA integrated within the B genome of banana (endogenous BSV-eBSV) forming a viral genome for de novo viral particles. Both forms can be infectious in banana plants. The BSV phylogeny is polyphyletic with BSV distributed in two clades. Clade 1 clusters BSV species that occur worldwide and may have an eBSV counterpart, whereas Clade 3 only comprises BSV species from Uganda. Clearly, two distinct origins explain such BSV diversity. However, the epidemiology/outbreaks of BSV remains unclear and the role of eBSV needs to be clarified. In this review, the biodiversity of BSV is explained and discussed in the light of field and molecular epidemiology data. A scheme is proposed for the co-evolution of BSV and banana based on old or recent infection hypotheses related to African domestication sites and banana dissemination to explain the disease context. PMID:24457073

  14. Artificial microRNA-derived resistance to Cassava brown streak disease.

    PubMed

    Wagaba, Henry; Patil, Basavaprabhu L; Mukasa, Settumba; Alicai, Titus; Fauquet, Claude M; Taylor, Nigel J

    2016-05-01

    Artificial miRNAs (amiRNA) were generated targeting conserved sequences within the genomes of the two causal agents of Cassava brown streak disease (CBSD): Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Transient expression studies on ten amiRNAs targeting 21nt conserved sequences of P1(CBSV and UCBSV), P3(CBSV and UCBSV), CI(UCBSV), NIb(CBSV and UCBSV), CP(UCBSV) and the un-translated region (3'-UTR) were tested in Nicotiana benthamiana. Four out of the ten amiRNAs expressed the corresponding amiRNA at high levels. Transgenic N. benthamiana plants were developed for the four amiRNAs targeting the P1 and NIb genes of CBSV and the P1 and CP genes of UCBSV and shown to accumulate miRNA products. Transgenic plants challenged with CBSV and UCBSV isolates showed resistance levels that ranged between ∼20-60% against CBSV and UCBSV and correlated with expression levels of the transgenically derived miRNAs. MicroRNAs targeting P1 and NIb of CBSV showed protection against CBSV and UCBSV, while amiRNAs targeting the P1 and CP of UCBSV showed protection against UCBSV but were less efficient against CBSV. These results indicate a potential application of amiRNAs for engineering resistance to CBSD-causing viruses in cassava. PMID:26912232

  15. Laser Activated Streak Camera for Measurement of Electron Pulses with Femtosecond Resolution

    NASA Astrophysics Data System (ADS)

    Zandi, Omid; Desimone, Alice; Wilkin, Kyle; Yang, Jie; Centurion, Martin

    2015-05-01

    The duration of femtosecond electron pulses used in time-resolved diffraction and microscopy experiments is challenging to measure in-situ. To overcome this problem, we have fabricated a streak camera that uses the time-varying electric field of a discharging parallel plate capacitor. The capacitor is discharged using a laser-activated GaAs photoswitch, resulting in a damped oscillation of the electric field. The delay time between the laser pulse and electron pulse is set so that the front and back halves of the bunch encounter opposite electric fields of the capacitor and are deflected in opposite directions. Thus, the electron bunch appears streaked on the detector with a length proportional to its duration. The temporal resolution of the streak camera is proportional to the maximum value of the electric field and the frequency of the discharge oscillation. The capacitor is charged by high voltage short pulses to achieve a high electric field and prevent breakdown. We have achieved an oscillation frequency in the GHz range by reducing the circuit size and hence its inductance. The camera was used to measure 100 keV electron pulses with up to a million electrons that are compressed transversely by magnetic lenses and longitudinally by an RF cavity. This work was supported mainly by the Air Force Office of Scientific Research, Ultrashort Pulse Laser Matter Interaction program, under grant # FA9550-12-1-0149.

  16. Corrosion cast study of the canine hepatic veins.

    PubMed

    Uršič, M; Vrecl, M; Fazarinc, G

    2014-11-01

    This study presents a detailed description of the distribution, diameters and drainage patterns of hepatic veins on the basis of the corrosion cast analysis in 18 dogs. We classified the hepatic veins in three main groups: the right hepatic veins of the caudate process and right lateral liver lobe, the middle hepatic veins of the right medial and quadrate lobes and the left hepatic veins of both left liver lobes and the papillary process. The corrosion cast study showed that the number of the veins in the Nomina Anatomica Veterinaria and most anatomical textbooks is underestimated. The number of various-sized hepatic veins of the right liver division ranged from 3 to 5 and included 1 to 4 veins from the caudate process and 2 to 4 veins from the right lateral liver lobe. Generally, in all corrosion casts, one middle-sized vein from the right part of the right medial lobe, which emptied separately in the caudal vena cava, was established. The other vein was a large-sized vein from the remainder of the central division, which frequently joined the common left hepatic vein from the left liver lobes. The common left hepatic vein was the largest of all the aforementioned hepatic veins. PMID:25448906

  17. The Incidence, Clinical Importance and Management of Incompetent Gastrocnemius Vein

    PubMed Central

    2016-01-01

    Purpose: To report the incidence, clinical importance and management of the incompetent gastrocnemius vein. Methods: The incompetency was examined by duplex and pulse-Doppler ultrasound at the popliteal fossa in a standing position between July 2006 and August 2014. Results: Among 1805 legs surveyed, 14 legs showed primary incompetent gastrocnemius vein (0.78%). The incompetency was in medial gastrocnemius vein in 13 legs (93%). Clinical manifestation was varicose vein in the small saphenous territory in nine, varicose vein in great saphenous territory in one, congestive dermatitis in two, calf clamp in one and no symptom in one. The nine cases with varicose vein in the small saphenous territory received surgical management. These included three cases with residual varicose veins after saphenopopliteal disconnection and stripping small saphenous vein. The root of the gastrocnemius vein was divided leaving no complication. In cases without varicose vein in small saphenous territory, an elastic compression socks was useful in some degree. Conclusions: Incompetency of gastrocnemius vein was not so rare. When a case is accompanied by small saphenous varicose veins, division of the root of gastrocnemius vein along with small saphenous vein stripping is recommended in order to reduce residual varicose vein. PMID:27087871

  18. Low Albedo Surfaces and Eolian Sediment: Mars Orbiter Camera Views of Western Arabia Terra Craters and Wind Streaks

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2001-01-01

    High spatial resolution (1.5 to 12 m/pixel) Mars Global Surveyor Mars Orbiter Camera images obtained September 1997 through June 2001 indicate that the large, dark wind streaks of western Arabia Terra each originate at a barchan dune field on a crater floor. The streaks consist of a relatively thin coating of sediment deflated from the dune fields and their vicinity. This sediment drapes a previous mantle that more thickly covers nearly all of western Arabia Terra. No dunes or eolian bedforms are found within the dark wind streaks, nor do any of the intracrater dunes climb up crater walls to provide sand to the wind streaks. The relations between dunes, wind streak, and subjacent terrain imply that dark-toned grains finer than those which comprise the dunes are lifted into suspension and carried out of the craters to be deposited on the adjacent terrain. Such grains are most likely in the silt size range (3.9-62.5 micrometers). The streaks change in terms of extent, relative albedo, and surface pattern over periods measured in years, but very little evidence for recent eolian activity (dust plumes, storms, dune movement) has been observed.

  19. Double left renal veins and multiple right renal veins found in Japanese adults.

    PubMed

    Yahiro, J; Miyoshi, S

    1993-12-01

    A case of circumaortic renal venous collar, the first such collar to be observed in a Japanese female cadaver, is presented, and its anatomical organization is compared with that in another case in which four right renal veins accompanied four right and three left renal arteries in a Japanese male cadaver. Double left renal veins are formed by persistence of a more central retroaortic venous anastomosis, in contrast to multiple right renal veins, which are formed by persistence of some embryonic renal veins arranged in ladder-like patterns. In our case, the dorsal limb of the renal collar communicated with the azygos system veins and lumbar veins. The azygos system veins were considered to have atrophied as a result of some persisting retroaortic venous anastomoses located in the thorax. Therefore, we believe that the renal collar was related to the atrophy of the azygos system veins. To determine whether there are racial differences in incidence of renal collar, further studies in Asians are required. PMID:8202308

  20. A clinicopathological study of human yellow fever*

    PubMed Central

    Francis, T. I.; Moore, D. L.; Edington, G. M.; Smith, J. A.

    1972-01-01

    During an epidemic of yellow fever in the Jos Plateau area of Nigeria, 9 adult males with clinically diagnosed yellow fever were studied by haematological, biochemical, virological, serological, and liver biopsy methods. The ages of the patients ranged from 20 to 55 years and the duration of illness was 3-62 days. No virus was isolated from any patient but all patients should biochemical evidence of severe hepatocellular damage. Leucopenia was a feature of the late acute stage of the disease. Five sera had antibodies to yellow fever at titres greater than 1: 32, 3 of them being monospecific for yellow fever. The classical histological features of yellow fever were present only in the acute or late acute stages, when complement-fixation tests may be negative. With convalescence and the production of complement-fixing antibodies in high titres, the histological features resembled those of a persisting nonspecific hepatitis. In an endemic area, the histological features of yellow fever will depend on the stage of the disease and a picture of nonspecific hepatitis would not exclude yellow fever in the absence of confirmation from serological tests. ImagesFig. 1Fig. 2AFig. 2BFig. 3Fig. 4Fig. 5Fig. 6 PMID:4538039

  1. Animal Model of Acute Deep Vein Thrombosis

    SciTech Connect

    Roy, Sumit; Laerum, Frode; Brosstad, Frank; Kvernebo, Knut; Sakariassen, Kjell S.

    1998-07-15

    Purpose: To develop an animal model of acute deep vein thrombosis (DVT). Methods: In part I of the study nine juvenile domestic pigs were used. Each external iliac vein was transluminally occluded with a balloon catheter. Thrombin was infused through a microcatheter in one leg according to one of the following protocols: (1) intraarterial (IA): 1250 U at 25 U/min in the common femoral artery (n= 3); (2) intravenous (IV): 5000 U in the popliteal vein at 500 U/min (n= 3), or at 100 U/min (n= 3). Saline was administered in the opposite leg. After the animals were killed, the mass of thrombus in the iliofemoral veins was measured. The pudendoepiploic (PEV), profunda femoris (PF), and popliteal veins (PV) were examined. Thrombosis in the tributaries of the superficial femoral vein (SFVt) was graded according to a three-point scale (0, +, ++). In part II of the study IV administration was further investigated in nine pigs using the following three regimens with 1000 U at 25 U/min serving as the control: (1) 1000 U at 100 U/min, (2) 250 U at 25 U/min, (3) 250 U at 6.25 U/min. Results: All animals survived. In part I median thrombus mass in the test limbs was 1.40 g as compared with 0.25 g in the controls (p= 0.01). PEV, PFV and PV were thrombosed in all limbs infused with thrombin. IV infusion was more effective in inducing thrombosis in both the parent veins (mass 1.32-1.78 g) and SVFt (++ in 4 of 6 legs), as compared with IA infusion (mass 0.0-1.16 g; SFVt ++ in 1 of 3 legs). In part II thrombus mass in axial veins ranged from 1.23 to 2.86 g, and showed no relationship with the dose of thrombin or the rate of infusion. Tributary thrombosis was less extensive with 250 U at 25 U/min than with the other regimens. Conclusion: Slow distal intravenous thrombin infusion in the hind legs of pigs combined with proximal venous occlusion induces thrombosis in the leg veins that closely resembles clinical DVT in distribution.

  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

  3. Giacomini vein: thigh extension of the small saphenous vein - report of two cases and review of the literature

    PubMed Central

    Natsis, K; Paraskevas, G; Lazaridis, N; Sofidis, G; Piagkou, M

    2015-01-01

    Background Varicose vein surgery is very commonly performed. Also, it is very frequently employed for recurrent disease. The recognition of the normal or variant veins, inducing incompetency, is a prerequisite for effective treatment. The thigh extension of the small saphenous vein, the so-called Giacomini vein, was extensively described in 1873 by Carlo Giacomini in an incidence of 72%. However, such a vein is usually underestimated in classic surgical textbooks. Description of cases We present two cases of Giacomini vein found in two cadavers, dissected for academic purposes in the Department of Anatomy, where the small saphenous vein displayed a thigh extension without terminating into the popliteal vein. In one case Giacomini vein drained into the large saphenous vein, while in the other case the vein divided into two branches, separately draining into the large saphenous vein and the subcutaneous tissue of the gluteal region. Conclusion Due to the fact that Giacomini vein could be incompetent, associated with or without varicose saphenous vein trunks, the vascular surgeon should keep in mind that anatomical entity, to include it in preoperative ultrasound scanning control. Moreover, this vein could be utilized as an autologous graft, when the large saphenous is not available. Hippokratia 2015; 19 (3): 263-265.

  4. 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.

  5. 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

  6. Spontaneous Resolution of Portal Vein Thrombosis

    PubMed Central

    Banumukala, Vishnu; Babu, Adarsh

    2008-01-01

    A 56-year-old male was admitted with symptoms of belching, abdominal pain and weight loss of 2 weeks duration. Examination revealed hepatosplenomegaly which was confirmed by computed tomography (CT). CT images also revealed filling defects in the portal vein and intrahepatic branches consistent with thrombosis and hepatosplenic infarcts. Alkaline phosphatase was elevated at 688 units, all other investigations, including full blood count, coagulation screen and tumour markers, were normal. Magnetic resonance cholangiopancreatography did not reveal any mass in the porta hepatis. Upper gastrointestinal endoscopy and colonoscopy were normal. Liver biopsy was normal and did not reveal any evidence of lymphoma. The raised alkaline phosphatase settled to reference range over a period of 3 weeks. Thrombophilia screen was negative. Contrast CT of the abdomen performed after 4 weeks displayed revascularisation of the previously thrombosed portal vein and intrahepatic branches. The patient has remained asymptomatic since and we note spontaneous recanalisation of the previously occluded portal vein. PMID:21490872

  7. Spontaneous resolution of portal vein thrombosis.

    PubMed

    Banumukala, Vishnu; Babu, Adarsh

    2008-01-01

    A 56-year-old male was admitted with symptoms of belching, abdominal pain and weight loss of 2 weeks duration. Examination revealed hepatosplenomegaly which was confirmed by computed tomography (CT). CT images also revealed filling defects in the portal vein and intrahepatic branches consistent with thrombosis and hepatosplenic infarcts. Alkaline phosphatase was elevated at 688 units, all other investigations, including full blood count, coagulation screen and tumour markers, were normal. Magnetic resonance cholangiopancreatography did not reveal any mass in the porta hepatis. Upper gastrointestinal endoscopy and colonoscopy were normal. Liver biopsy was normal and did not reveal any evidence of lymphoma. The raised alkaline phosphatase settled to reference range over a period of 3 weeks. Thrombophilia screen was negative. Contrast CT of the abdomen performed after 4 weeks displayed revascularisation of the previously thrombosed portal vein and intrahepatic branches. The patient has remained asymptomatic since and we note spontaneous recanalisation of the previously occluded portal vein. PMID:21490872

  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. Deringing procedure for congenital pulmonary vein stenosis.

    PubMed Central

    Victor, S; Nayak, V M

    1995-01-01

    We operated on a 14-year-old boy who had an echocardiographic diagnosis of ventricular septal defect. At surgery we found, in addition, an anomalous and obstructive intraventricular muscle bundle. Detection of a continuous thrill over the right pulmonary veins, prior to cardiopulmonary bypass, led to exploration of the left atrium. The ostia of the right superior and inferior pulmonary veins were impeded by circumferential membranous rings of endocardium with central stenotic openings. Excision of these annular rings relieved the obstruction. The left lung was drained by a long intrapericardial common venous channel that entered the left atrium through a stenotic ostium; excision of an annular ridge of endocardium restored normal flow. The patient remains asymptomatic after 23 months. The case is reported for the new deringing technique and the rarity of successful correction of congenital pulmonary vein stenosis. Images PMID:7647600

  10. 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

  11. Can tuffisite veins help dictate eruption styles?

    NASA Astrophysics Data System (ADS)

    Kolzenburg, S.; Heap, M. J.; Lavallee, Y.; Russell, J. K.; Meredith, P. G.; Dingwell, D. B.

    2010-12-01

    The ability of magmas to degas during ascent may affect eruption style. The permeability of the magma and/or the conduit wall rocks may therefore dictate whether an eruption will be explosive or effusive. Fractures increase permeability. Fractures filled by veins of autoclastic, cataclastic and tuffisitic glass shards and crystal fragments are common in shallow conduit systems. These veins have the potential to dramatically increase permeability and provide pathways for gas loss. Here we present the first study on the porosity, permeability, strength, P-and S-wave and dynamic elastic moduli of andesite containing tuffisite veins at Volcán de Colima, Mexico. Porosity was measured via pycnometry. The strength and mechanisms of deformation were investigated on tuffisite-bearing and tuffisite-free samples in a uniaxial press at 940°C by loading at 2 MPa/min until failure. The permeability, P- and S-wave velocity, and dynamic elastic moduli were measured in a high-pressure permeameter/pore volumometer up to effective confining pressures of 50 MPa (ca. 2km depth). Measurements were made on cylindrical samples prepared as: (1) without tuffisite veins and with tuffisite veins (2) perpendicular and (3) sub-parallel to flow (i.e., the samples’ axial direction). Petrographic analysis reveals that the tuffisites are comprised almost exclusively of micron-size crystal fragments. Dilatometric measurements of tuffisite (10°C/min up to 1000°C), failed to reveal a Tg, indicating the absence of interstitial glass. In contrast, the dome rocks exhibits viscous relaxation between 770 and 885 °C, indicating glass. The high-temperature (940°C) deformation experiments on samples containing tuffisite veins showed an absence of ductile deformation and a uniaxial strength of 116 MPa; i.e, slightly weaker than tuffisite-free rock (~130 MPa) and stronger than erupted dome lavas (~30 MPa). The presence of tuffisite increases the porosity. Permeability measurements show that tuffisite

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 35. Ca. 1930 historic view facing northeast, showing Yellow Mill ...

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

    35. Ca. 1930 historic view facing northeast, showing Yellow Mill Bridge and inset showing former ca. 1901 Yellow Mill Bridge. Photo located at the Bridgeport Public Library, Bridgeport, CT. - Yellow Mill Bridge, Spanning Yellow Mill Channel at Stratford Avenue, Bridgeport, Fairfield County, CT

  8. 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...

  9. 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)

  10. 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

  11. Teachable Fiction Comes to Yellow Sky.

    ERIC Educational Resources Information Center

    Tietz, Stephen

    2001-01-01

    Proposes that teachable fiction is efficient, strategically sound, and very visual. Analyzes Stephen Crane's "The Bride Comes to Yellow Sky" to show it fulfills these three characteristics. Suggests the story should be taught later in the semester. (PM)

  12. 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.

  13. Quantification of southern rice black streaked dwarf virus and rice black streaked dwarf virus in the organs of their vector and nonvector insect over time.

    PubMed

    Hajano, Jamal-U-Ddin; Wang, Biao; Ren, Yingdang; Lu, Chuantao; Wang, Xifeng

    2015-10-01

    Southern rice black streaked dwarf virus (SRBSDV) and rice black streaked dwarf virus (RBSDV) are serious rice-infecting reoviruses, which are transmitted by different planthoppers in a persistent propagative manner. In this study, we quantitatively compared the spatial distribution of SRBSDV and RBSDV contents over time in their vector and nonvector insects using real time-PCR. Genome equivalent copies (GEC) were assessed every 2 days from 0 to 14 days after a 3-days acquisition access period (AAP) on infected plants. Results revealed 293.2±21.6 to 404.1±46.4 SRBSDV GEC/ng total RNA in whole body of white-backed planthopper (WBPH, Sogatella furcifera) at day 0 and 12 and 513.5±88.4 to 816.8±110.7 RBSDV GEC/ng total RNA in the whole body of small brown planthopper (SBPH, Laodelphax striatellus) at day 0 and 14, respectively, after 3-days AAP. Highest GEC of both viruses were found in the gut of their respective vectors. Although SRBSDV was detected in the gut of SBPH, it did not spread into the hemolymph or other organs. After an 8-day latent period, the transmission efficiency of SRBSDV and RBSDV by their respective vectors was significantly positively correlated with GEC in the salivary gland (r(2)=0.7808, P=0.0036 and r(2)=0.9351, P<0.0001, respectively, at α=0.05). Together, these results confirm that accumulation of >200 SRBSDV or RBSDV GEC/ng total RNA in the gut of vector, indicated threshold for further spread and the virus content in the salivary gland was significantly correlated with transmission efficiency by their respective vectors. PMID:26116274

  14. [Retinal vein occlusion: an interdisciplinary approach].

    PubMed

    Hatz, Katja; Martinez, Maria

    2016-01-01

    Retinal vein occlusion provide a common cause of significant visual reduction but also late ocular complications. The medical care of these patients pursue two goals: On the one hand vision threatening complications need to be identified and treated, and on the other hand treatable risk factors are need to be identified and treated. This paper summarizes the common ophthalmological therapeutic approaches as well as recommended medical evaluations carried out by the general practitioner. This supports the interdisciplinary approach in evaluating and treating retinal vein occlusions by ophthalmologists and the general practitioners/specialist in internal medicine. PMID:26982647

  15. Saphenous vein graft aneurysm: an incidental finding

    PubMed Central

    Rana, Omar; Greaves, Kim; Shepherd, David; Parvin, Simon; Swallow, Rosie

    2009-01-01

    Saphenous vein graft aneurysm (SVGA) is an uncommon complication of coronary artery bypass graft surgery (CABG). An 82-year-old man underwent contrast-enhanced computed tomography to investigate aorto-iliac disease. He was coincidentally noted to have an aneurysm of the saphenous vein graft to his right coronary artery. This was visualised on transthoracic echocardiography, computed tomography and coronary angiography. In the absence of symptoms and in view of high surgical risk, conservative management with anticoagulation was chosen. The patient was commenced on warfarin and remains asymptomatic. PMID:21686801

  16. Vein morphology, host rock deformation and the origin of the fabrics of echelon mineral veins

    NASA Astrophysics Data System (ADS)

    Nicholson, R.

    A system of sigmoidal echelon veins from a sample of sandstone from the Upper Carboniferous Culm sequence of southwest England is described. Veins are separated from one another by strips of sandstone, and divided internally by thin seams with crack—seal fabrics. The latter extend as thin veins into the sandstone host rock without change of fabric. Seams appear to be merely parts of crack—seal veins formed in a first phase of deposition in only minutely opened fractures. This phase ended as rates of fracture opening greatly increased. To allow for this widespread opening host rock between dilatating fractures (sandstone strips and seams) had to be deformed. This deformation was limited, however, to rotation, bending and fracture. Shear displacement was a function of dilatation, not zone-parallel ductile shear strain. The textures of the quartz and carbonate aggregates filling the sigmoidal veins show that second-phase crystallization took place into cavities opening more rapidly than growth was able to fill them. Growth for the greater part took place from fibres in seams and not off vein walls of the sandstone host rock. Coarsest aggregates fill the arcs of folds in seams, where rates of vein opening might be expected to have been highest and the scope for competitive cavity growth greatest.

  17. Measuring 8–250 ps short pulses using a high-speed streak camera on kilojoule, petawatt-class laser systems

    SciTech Connect

    Qiao, J.; Jaanimagi, P. A.; Boni, R.; Bromage, J.; Hill, E.

    2013-07-15

    Short-pulse measurements using a streak camera are sensitive to space-charge broadening, which depends on the pulse duration and shape, and on the uniformity of photocathode illumination. An anamorphic-diffuser-based beam-homogenizing system and a space-charge-broadening calibration method were developed to accurately measure short pulses using an optical streak camera. This approach provides a more-uniform streak image and enables one to characterize space-charge-induced pulse-broadening effects.

  18. Synchronous time-resolved optical and x-ray emission from simultaneous optical and x-ray streak cameras driven by a master ramp generator

    SciTech Connect

    Balmer, J.E.; Lampert, W.; Roschger, E.; Hares, J.D.; Kilkenny, J.D.

    1985-05-01

    An optical and an x-ray streak camera have been synchronized by driving the deflection plates of both cameras from the same ramp generator. The relative timing of the two cameras was calibrated by running UV light onto the x-ray streak camera. The x-ray streak camera was then used to measure the time of the x-ray emission from a laser plasma with respect to the laser pulse.

  19. 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 6.7±1.8 mm and 12.5±8.5 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

  20. Clinical Significance of the Soleal Vein and Related Drainage Veins, in Calf Vein Thrombosis in Autopsy Cases with Massive Pulmonary Thromboembolism

    PubMed Central

    Kageyama, Norimasa

    2015-01-01

    Objective: To clarify the histopathological characteristics of deep vein thrombosis (DVT) resulting in lethal pulmonary thromboembolism (PE). Subjects and Methods: We investigated 100 autopsy cases of PE from limb DVT. The distribution and chronology of DVT in each deep venous segment were examined. Venous segments were classified into three groups: iliofemoral vein, popliteal vein and calf vein (CV). The CV was subdivided into two subgroups, drainage veins of the soleal vein (SV) and non drainage veins of SV. Results: Eighty-nine patients had bilateral limb DVTs. CV was involved in all limbs with DVT with isolated calf DVTs were seen in 47% of patients. Fresh and organized thrombi were detected in 84% of patients. SV showed the highest incidence of DVTs in eight venous segments. The incidence of DVT gradually decreased according to the drainage route of the central SV. Proximal tips of fresh thrombi were mainly located in the popliteal vein and tibioperoneal trunk, occurring in these locations in 63% of limbs. Conclusions: SV is considered to be the primary site of DVT; the DVT then propagated to proximal veins through the drainage veins. Lethal thromboemboli would occur at proximal veins as a result of proximal propagation from calf DVTs. PMID:27087868

  1. Splenic Vein Thrombosis with Oesophageal Varices: A Late Complication of Umbilical Vein Catheterization

    PubMed Central

    Vos, L. J. M.; Potocky, V.; Bröker, 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

  2. Transgenic RNA interference (RNAi)-derived field resistance to cassava brown streak disease.

    PubMed

    Ogwok, Emmanuel; Odipio, John; Halsey, Mark; Gaitán-Solís, Eliana; Bua, Anton; Taylor, Nigel J; Fauquet, Claude M; Alicai, Titus

    2012-12-01

    Cassava brown streak disease (CBSD), caused by the Ipomoviruses Cassava brown streak virus (CBSV) and Ugandan Cassava brown streak virus (UCBSV), is considered to be an imminent threat to food security in tropical Africa. Cassava plants were transgenically modified to generate small interfering RNAs (siRNAs) from truncated full-length (894-bp) and N-terminal (402-bp) portions of the UCBSV coat protein (ΔCP) sequence. Seven siRNA-producing lines from each gene construct were tested under confined field trials at Namulonge, Uganda. All nontransgenic control plants (n = 60) developed CBSD symptoms on aerial tissues by 6 months after planting, whereas plants transgenic for the full-length ΔCP sequence showed a 3-month delay in disease development, with 98% of clonal replicates within line 718-001 remaining symptom free over the 11-month trial. Reverse transcriptase-polymerase chain reaction (RT-PCR) diagnostics indicated the presence of UCBSV within the leaves of 57% of the nontransgenic controls, but in only two of 413 plants tested (0.5%) across the 14 transgenic lines. All transgenic plants showing CBSD were PCR positive for the presence of CBSV, except for line 781-001, in which 93% of plants were confirmed to be free of both pathogens. At harvest, 90% of storage roots from nontransgenic plants were severely affected by CBSD-induced necrosis. However, transgenic lines 718-005 and 718-001 showed significant suppression of disease, with 95% of roots from the latter line remaining free from necrosis and RT-PCR negative for the presence of both viral pathogens. Cross-protection against CBSV by siRNAs generated from the full-length UCBSV ΔCP confirms a previous report in tobacco. The information presented provides proof of principle for the control of CBSD by RNA interference-mediated technology, and progress towards the potential control of this damaging disease. PMID:22845735

  3. Absolute calibration method for nanosecond-resolved, time-streaked, fiber optic light collection, spectroscopy systems

    SciTech Connect

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

    2012-08-15

    This paper describes a convenient and accurate method to calibrate fast (<1 ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such systems are inherently difficult to calibrate due to the lack of sufficiently intense, calibrated light sources. Such a system is used to collect spectral data on plasmas generated in electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA) at Sandia National Laboratories. On RITS, plasma light is collected through a small diameter (200 {mu}m) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ('hotspot') was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/cm{sup 2}/steradian/nm). Error analysis shows this method to be accurate to within +/- 20%, which represents a high level of accuracy for this type of measurement.

  4. Significant seismic streaks corresponding to lithological contrasts in Mesozoic and Paleozoic accretion units, southwest Japan

    NASA Astrophysics Data System (ADS)

    Maeda, S.; Toda, S.; Katao, H.

    2014-12-01

    While high-density seismic streaks are commonly seen in aftershocks of a strike-slip earthquake, significant linear clusters in background seismicity are rare. A typical example of such sustained streaks is observed along the creeping section of the San Andreas fault, in which strain localization associated with frictional heterogeneity takes a responsibility. Here we show other examples from Tamba and Wakayama regions, around Osaka-Kyoto district, where a number of several-to-20-km-long seismic streaks are observed. We explore the role of geologic heterogeneity into the seismicity comparing spatial distribution of earthquakes with geologic structure in both regions, where a significant high background rate of seismicity has been continuously recorded since the mid-1900. Epicenters of numerous small earthquakes are located mainly on the Mesozoic metamorphic rocks and Mesozoic-Paleozoic accretion units, whereas low seismicity is characterized in granite and ultra-mafic rocks. Within the Wakayama seismic zone, in particular, we observe many E-W and ENE-WSW trending dense seismic clusters in hypocenters of Japan Meteorological Agency (JMA) data relocated with the hypo DD algorithm of Waldhauser and Ellsworth (2000). Most of the E-W trending seismic clusters possibly correspond to the E-W trending local scale geologic faults, folds, bedding planes, and schistosity. However, well-determined fault plane solutions by JMA and the National Research Institute for Earth Science and Disaster Prevention (NIED) show NS-trending reverse faults corresponding to EW compression. We further sought the focal mechanisms for smaller earthquakes using waveform data recorded in the SATARN seismic network system of DPRI, Kyoto University. As a result, among the many reverse fault mechanisms, we found some amounts of strike-slip ones, which may associate with the visible EW-trending seismic clusters.

  5. Absolute calibration method for nanosecond-resolved, time-streaked, fiber optic light collection, spectroscopy systems

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

    This paper describes a convenient and accurate method to calibrate fast (<1 ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such systems are inherently difficult to calibrate due to the lack of sufficiently intense, calibrated light sources. Such a system is used to collect spectral data on plasmas generated in electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA) at Sandia National Laboratories. On RITS, plasma light is collected through a small diameter (200 μm) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ("hotspot") was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/cm2/steradian/nm). Error analysis shows this method to be accurate to within +/- 20%, which represents a high level of accuracy for this type of measurement.

  6. A Dust Devil Making a Streak and Climbing a Crater Wall

    NASA Technical Reports Server (NTRS)

    2002-01-01

    MGS MOC Release No. MOC2-318, 8 August 2002 [figure removed for brevity, see original site] One of the key elements of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission is to look for and monitor changes taking place on the planet over the course of a second--and, eventually, a third--martian year. MGS is now well into its second Mars year, which will draw to a close in December 2002. Among the changes the MOC has observed are streaks believed to be caused by the passage of dust devils. Thousands of MOC images show these streaks, dozens show that they change over time, but far fewer images have actually captured a dust devil in the act of creating a streak. At the center right of this image (above left) is a dust devil that, on May 21, 2002, was seen climbing the wall of a crater at 4.1oS, 9.5oW. This crater (above right) is in western Terra Meridiani. The dust devil was moving toward the northeast (upper right), leaving behind a dark trail where a thin coating of surficial dust was removed or disrupted as the dust devil advanced. Dust devils most commonly form after noon on days when the martian air is still (that is, when there isn't even a faint breeze). On such days, the ground is better able to heat up the air immediately above the surface. As the warmed near-surface air begins to rise, it also begins to spin, creating a vortex. The spinning column then moves across the surface and picks up loose dust (if any is present). The dust makes the vortex visible and gives it a tornado-like appearance. The dust devil in this image has a very short, dark shadow cast to the right of the bright column; this shadow is short because the sun was nearly overhead.

  7. Effect of Amirkabiria odorastissima mozaffarian on the development and progression of fatty streaks in hypercholesterolemic rabbits.

    PubMed

    Asgary, S; Naderi, Gh; Dashti, Gh; Paknahad, Z

    2004-05-01

    New studies have introduced atherosclerosis as an inflammatory disease. Different factors affect the development of inflammation that can be linked to free radicals, hypertention, diabetes mellitus, genetic changes, hypercholesterolemia and some of the microorganisms. Using anti-inflammatory drugs can be useful in preventing atherosclerosis. Finding drugs from natural sources and without side-effects can be useful. Amirkabiria odoratissima (umbelliferae) is from Iranian fl ora and is used traditionally as an anti-inflammatory drug. This study was designed to assess the effects of this plant on the development and progression of fatty streaks. Male rabbits were fed: (a) rabbit chow; (b) 1% cholesterol diet; (c) cholesterol diet supplemented with the plant; (d) normal diet supplemented with the plant. After 12 weeks, the animals were sacrificed and the aorta, right and left branches of coronary arteries were dissected and histologically processed. Before and after the end of the study, biochemical factors were measured. The amounts of cholesterol, LDL, HDL, triglyceride and fasting blood sugar (FBS) were determined by enzymatic methods, quantitative CRP was determined by turbidimetric methods, malondialdehyde (MDA) and antioxidant capacity were determined by speceterophotometric methods. The results indicate that there is a significant difference between the groups supplemented with herbal medicine and others (p < 0.05) in the mean grade of fatty streak of right and left coronary artery and aorta. At the end of the 12-week period cholesterol, LDL and CRP were significantly reduced in the groups which received herbal medicine (p < 0.05). The data suggests that Amirkabiria odoratissima Mozaffarian has beneficial effects to prevent development of fatty streak; however, further studies are needed to understand the mechanisms whereby this plant exerts its anti-atherosclerotic effects. PMID:15173995

  8. Pancreatectomy with vein reconstruction: technique matters

    PubMed Central

    Dua, Monica M; Tran, Thuy B; Klausner, Jill; Hwa, Kim J; Poultsides, George A; Norton, Jeffrey A; Visser, Brendan C

    2015-01-01

    Background A variety of techniques have been described for portal vein (PV) and/or superior mesenteric vein (SMV) resection/reconstruction during a pancreatectomy. The ideal strategy remains unclear. Methods Patients who underwent PV/SMV resection/reconstruction during a pancreatectomy from 2005 to 2014 were identified. Medical records and imaging were retrospectively reviewed for operative details and outcomes, with particular emphasis on patency. Results Ninety patients underwent vein resection/reconstruction with one of five techniques: (i) longitudinal venorrhaphy (LV, n = 17); (ii) transverse venorrhaphy (TV, n = 9); (iii) primary end-to-end (n = 28); (iv) patch venoplasty (PV, n = 17); and (v) interposition graft (IG, n = 19). With a median follow-up of 316 days, thrombosis was observed in 16/90 (18%). The rate of thrombosis varied according to technique. All patients with primary end-to-end or TV remained patent. LV, PV and IG were all associated with significant rates of thrombosis (P = 0.001 versus no thrombosis). Comparing thrombosed to patent, there were no differences with respect to pancreatectomy type, pre-operative knowledge of vein involvement and neoadjuvant therapy. Prophylactic aspirin was used in 69% of the total cohort (66% of patent, 81% of thrombosed) and showed no protective benefit. Conclusions Primary end-to-end and TV have superior patency than the alternatives after PV/SMV resection and should be the preferred techniques for short (<3 cm) reconstructions. PMID:26223388

  9. 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

  10. Puzzles in practice: splenic vein thrombosis.

    PubMed

    McIntyre, Brittany; Marsh, Melanie; Walden, Jeffrey

    2016-06-01

    This report details a 58-year-old gentleman who presented to his outpatient primary care physician's clinic several times over four weeks for ongoing epigastric pain radiating into his left flank, dry heaving, and constipation. He was presumed to have gastritis at each visit and prescribed escalating doses of proton pump inhibitors. Due to the unrelenting pain, he eventually was admitted to the hospital and diagnosed with splenic vein thrombosis after computed tomography imaging of the abdomen. Our literature search revealed that pancreatic pathology is overwhelmingly the contributing factor to splenic vein thrombosis. Our patient had prominent collateral vasculature, suggesting that his splenic vein thrombosis was chronic in nature and likely the cause of his ongoing abdominal pain. Splenic vein thrombosis is an uncommon cause of abdominal pain, but one that should be included in the treating physician's differential diagnoses when abdominal pain is ongoing despite medical therapy. Although he had no evidence of initial findings on radiography, our patient was eventually diagnosed with biopsy-proven pancreatic cancer. Our case report demonstrates how patients presenting with persistent or worsening abdominal pain despite the use of proton pump inhibitors or other acid reducing agents and potential 'red flag' findings such as decreased appetite and weight loss should be worked up for other potential sources of abdominal pathology. PMID:27157637

  11. Crossectomy and great saphenous vein stripping.

    PubMed

    Winterborn, R J; Earnshaw, J J

    2006-02-01

    Crossectomy and stripping have been the standard of care for primary great saphenous varicose veins since the high failure rates of sclerotherapy became apparent in the 1970s. As the specialty of venous surgery has evolved, a number of clinical trials have established the optimal methods of surgical treatment, and the clinical benefit of routine stripping. Long-term trials, however, have uncovered a high recurrence rate after varicose vein surgery that approaches 70% after 10 years. There is much debate about whether this is the result of the dilatation of existing tributaries in the groin or the growth of new veins as a result of angiogenesis that follows surgical treatment and healing (neovascularisation). The addition of barrier technology to current crossectomy has the potential to improve the results of surgery in the future. In the meanwhile, new techniques are evolving to obliterate the great saphenous vein, including endovenous laser, radiofrequency ablation and foam sclerotherapy. Randomised clinical trials are urgently required to compare these new treatments against standard surgery, and they will need to focus on whether the short-term gains in reduced convalescence and morbidity are balanced by durable long-term results. PMID:16434942

  12. Left renal vein compression syndrome ("nutcracker phenomenon").

    PubMed

    Stassen, C M; Weil, E H; Janevski, B K

    1989-06-01

    Four cases are presented with clinical diagnosis of scrotal varicocele on the left side, and one case with ureter varices and left-sided haematuria as a result of compression of the left renal vein between the aorta and superior mesenteric artery (SMA), also known as "nutcracker phenomenon". The clinical signs and the radiological diagnostic methods of the condition are discussed. PMID:2544950

  13. 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 Masson’s 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

  14. 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

  15. Direct Shock-Timing Measurements in CH Using Streaked X-Ray Radiography

    NASA Astrophysics Data System (ADS)

    Nilson, P. M.; Lafon, M.; Stillman, C. R.; Mileham, C.; Boni, R.; Boehly, T. R.; Froula, D. H.; Meyerhofer, D. D.

    2014-10-01

    One-dimensional streaked x-ray radiography is used to measure shock coalescence in multishocked plastic. A two-shock system was generated using a ramped drive on the OMEGA EP Laser System. The data show the first shock wave propagating into solid material, followed 2 ns later by the second shock wave. The measured shock trajectories were used to track the system dynamics and determine the shock-coalescence times for different initial shock strengths. The measured shock timings are compared to radiation-hydrodynamic model predictions. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  16. Physics and roller coasters-The Blue Streak at Cedar Point

    NASA Astrophysics Data System (ADS)

    Speers, Robert R.

    1991-06-01

    The use of a roller coaster for external classroom studies of kinematics, forces, dynamics, and energy conservation is discussed. Experimental accelerometer measurements of the vertical forces acting on riders of the Blue Streak at Cedar Point in Sandusky, Ohio are presented. Theoretically, the track profile is used to calculate/predict the vertical forces acting on a rider at the hilltops, valley bottoms, and several other points of interest along the track. Finally the experimental results and theoretical predictions are compared in the context of a rider's experiences.

  17. Capsule Ablator Inflight Performance Measurements Via Streaked Radiography Of ICF Implosions On The NIF*

    NASA Astrophysics Data System (ADS)

    Dewald, E. L.; Tommasini, R.; Mackinnon, A.; MacPhee, A.; Meezan, N.; Olson, R.; Hicks, D.; LePape, S.; Izumi, N.; Fournier, K.; Barrios, M. A.; Ross, S.; Pak, A.; Döppner, T.; Kalantar, D.; Opachich, K.; Rygg, R.; Bradley, D.; Bell, P.; Hamza, A.; Dzenitis, B.; Landen, O. L.; MacGowan, B.; LaFortune, K.; Widmayer, C.; Van Wonterghem, B.; Kilkenny, J.; Edwards, M. J.; Atherton, J.; Moses, E. I.

    2016-03-01

    Streaked 1-dimensional (slit imaging) radiography of 1.1 mm radius capsules in ignition hohlraums was recently introduced on the National Ignition Facility (NIF) and gives an inflight continuous record of capsule ablator implosion velocities, shell thickness and remaining mass in the last 3-5 ns before peak implosion time. The high quality data delivers good accuracy in implosion metrics that meets our requirements for ignition and agrees with recently introduced 2-dimensional pinhole radiography. Calculations match measured trajectory across various capsule designs and laser drives when the peak laser power is reduced by 20%. Furthermore, calculations matching measured trajectories give also good agreement in ablator shell thickness and remaining mass.

  18. Loop-mediated Isothermal Amplification Assay to Rapidly Detect Wheat Streak Mosaic Virus in Quarantined Plants

    PubMed Central

    Lee, Siwon; Kim, Jin-Ho; Choi, Ji-Young; Jang, Won-Cheoul

    2015-01-01

    We developed a loop-mediated isothermal amplification (LAMP) method to rapidly diagnose Wheat streak mosaic virus (WSMV) during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections. PMID:26674930

  19. Loop-mediated Isothermal Amplification Assay to Rapidly Detect Wheat Streak Mosaic Virus in Quarantined Plants.

    PubMed

    Lee, Siwon; Kim, Jin-Ho; Choi, Ji-Young; Jang, Won-Cheoul

    2015-12-01

    We developed a loop-mediated isothermal amplification (LAMP) method to rapidly diagnose Wheat streak mosaic virus (WSMV) during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections. PMID:26674930

  20. Temporal Characterization of Electron Beam Bunches with a Fast Streak Camera at the JLab FEL Facility

    SciTech Connect

    S. Zhang; S.V. Benson; D. Douglas; D. Hardy; C. Hernandez-Garcia; K. Jordan; G. Neil; Michelle D. Shinn

    2005-08-21

    The design and construction of an optical transport that brings synchrotron radiation from electron bunches to a fast streak camera in a remote area has become a useful tool for online observation of bunch length and stability. This paper will report on the temporal measurements we have done, comparison with simulations, and the on-going work for another imaging optical transport system that will make possible the direct measurement of the longitudinal phase space by measuring the bunch length as a function of energy