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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. 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...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. 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...

  5. Yellowing disease in zucchini squash produced by mixed infections of Cucurbit yellow stunting disorder virus and Cucumber vein yellowing virus.

    PubMed

    Gil-Salas, Francisco M; Peters, Jeff; Boonham, Neil; Cuadrado, Isabel M; Janssen, Dirk

    2011-11-01

    Zucchini squash is host to Cucurbit yellow stunting disorder virus (CYSDV), a member of the genus Crinivirus, and Cucumber vein yellowing virus (CVYV), a member of the genus Ipomovirus, both transmitted by the whitefly Bemisia tabaci. Field observations suggest the appearance of new symptoms observed on leaves of zucchini squash crops when both viruses were present. When infected during controlled experiments with CYSDV only, zucchini plants showed no obvious symptoms and the virus titer decreased between 15 and 45 days postinoculation (dpi), after which it was no longer detected. CVYV caused inconspicuous symptoms restricted to vein clearing on some of the apical leaves and the virus accumulated progressively between 15 and 60 dpi. Similar accumulations of virus followed single inoculations with the potyvirus Zucchini yellow mosaic virus (ZYMV) and plants showed severe stunting, leaf deformation, and mosaic yellowing. However, in mixed infections with CYSDV and CVYV, intermediate leaves showed chlorotic mottling which evolved later to rolling, brittleness, and complete yellowing of the leaf lamina, with exception of the veins. No consistent alteration of CVYV accumulation was detected but the amounts of CYSDV increased ≈100-fold and remained detectable at 60 dpi. Such synergistic effects on the titer of the crinivirus and symptom expression were not observed when co-infected with ZYMV.

  6. 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.

  7. A begomovirus associated with Ageratum yellow vein disease in Indonesia: evidence for natural recombination between tomato leaf curl Java virus and Ageratum yellow vein virus-[Java].

    PubMed

    Kon, T; Kuwabara, K; Hidayat, S H; Ikegami, M

    2007-01-01

    A begomovirus (2747 nucleotides) and a satellite DNA beta component (1360 nucleotides) have been isolated from Ageratum conyzoides L. plants with yellow vein symptoms growing in Java, Indonesia. The begomovirus is most closely related to Tomato leaf curl Java virus (ToLCJV) (91 and 98% in the total nucleotide and coat protein amino acid sequences, respectively), although the products of ORFs C1 and C4 are more closely related to those of Ageratum yellow vein virus-[Java] (91 and 95% identity, respectively). For this reason, the begomovirus it is considered to be a strain of ToLCJV and is referred to as ToLCJV-Ageratum. The virus probably derives from a recombination event in which nucleotides 2389-2692 of ToLCJV have been replaced with the corresponding region of the AYVV-[Java] genome, which includes the 5' part of the intergenic region and the C1 and C4 ORFs. Infection of A. conyzoides with ToLCJV-Ageratum alone produced no symptoms, but co-infection with DNAbeta induced yellow vein symptoms. Symptoms induced in Nicotiana benthamiana by ToLCJV-Ageratum, ToLCJV and AYVV-[Java] are consistent with the exchange of pathogenicity determinant ORF C4 during recombination.

  8. 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...

  9. 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...

  10. 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...

  11. First report of the complete sequence of Sida golden yellow vein virus from Jamaica.

    PubMed

    Stewart, Cheryl S; Kon, Tatsuya; Gilbertson, Robert L; Roye, Marcia E

    2011-08-01

    Begomoviruses are phytopathogens that threaten food security [18]. Sida spp. are ubiquitous weed species found in Jamaica. Sida samples were collected island-wide, DNA was extracted via a modified Dellaporta method, and the viral genome was amplified using degenerate and sequence-specific primers [2, 11]. The amplicons were cloned and sequenced. Sequence analysis revealed that a DNA-A molecule isolated from a plant in Liguanea, St. Andrew, was 90.9% similar to Sida golden yellow vein virus-[United States of America:Homestead:A11], making it a strain of SiGYVV. It was named Sida golden yellow vein virus-[Jamaica:Liguanea 2:2008] (SiGYVV-[JM:Lig2:08]). The cognate DNA-B, previously unreported, was successfully cloned and was most similar to that of Malvastrum yellow mosaic Jamaica virus (MaYMJV). Phylogenetic analysis suggested that this virus was most closely related to begomoviruses that infect malvaceous hosts in Jamaica, Cuba and Florida in the United States.

  12. Molecular characterization and population structure of blackberry vein banding associated virus, new Ampelovirus associated with yellow vein disease.

    PubMed

    Thekke-Veetil, Thanuja; Aboughanem-Sabanadzovic, Nina; Keller, Karen E; Martin, Robert R; Sabanadzovic, Sead; Tzanetakis, Ioannis E

    2013-12-26

    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 species of the genus Ampelovirus in the family Closteroviridae. The genome of the virus, provisionally named blackberry vein banding associated virus (BVBaV), consists of 18,643 nucleotides and contains 10 open reading frames (ORFs). These ORFs encode closterovirid signature replication-associated and quintuple gene block proteins, as well as four additional proteins of unknown function. Phylogenetic analyses of taxonomically relevant products consistently placed BVBaV in the same cluster with GLRaV-3 and other members of the subgroup I of the genus Ampelovirus. The virus population structure in the U.S. was studied using the replication associated polyprotein 1a, heat shock 70 homolog and minor coat proteins of 25 isolates. This study revealed significant intra-species variation without any clustering among isolates based on their geographic origin. Further analyses indicated that these proteins are under stringent purifying selections. High genetic variability and incongruent clustering of isolates suggested the possible involvement of recombination in the evolution of BVBaV.

  13. The genome sequence of pepper vein yellows virus (family Luteoviridae, genus Polerovirus).

    PubMed

    Murakami, Ritsuko; Nakashima, Nobuhiko; Hinomoto, Norihide; Kawano, Shinji; Toyosato, Tetsuya

    2011-05-01

    The complete genome of pepper vein yellows virus (PeVYV) was sequenced using random amplification of RNA samples isolated from vector insects (Aphis gossypii) that had been given access to PeVYV-infected plants. The PeVYV genome consisted of 6244 nucleotides and had a genomic organization characteristic of members of the genus Polerovirus. PeVYV had highest amino acid sequence identities in ORF0 to ORF3 (75.9 - 91.9%) with tobacco vein distorting polerovirus, with which it was only 25.1% identical in ORF5. These sequence comparisons and previously studied biological properties indicate that PeVYV is a distinctly different virus and belongs to a new species of the genus Polerovirus.

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

    PubMed

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

    2010-11-01

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

  15. 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...

  16. The begomoviruses Honeysuckle yellow vein mosaic virus and Tobacco leaf curl Japan virus with DNAbeta satellites cause yellow dwarf disease of tomato.

    PubMed

    Ogawa, T; Sharma, P; Ikegami, M

    2008-11-01

    The complete nucleotide sequences of two begomoviruses (Nara virus-1 and Nara virus-2), a satellite DNA (DNAbeta-Nara) and defective DNAs were obtained from honeysuckle (Lonicera japonica) showing characteristic yellow vein mosaic symptoms in Nara Prefecture, Japan. One begomovirus (Ibaraki virus) and a satellite DNA (DNAbeta-Ibaraki) was isolated and cloned from honeysuckle plants exhibited typical yellowing of veins and small elliptical shaped enations along veins on the under side of the leaves in Ibaraki Prefecture, Japan. The genome organization of the three viruses is the same as those of other Old World monopartite begomoviruses. Nara virus-1 had overall nucleotide sequence identity with Nara virus-2 of 94% and Ibaraki virus of 90%. DNAbeta-Nara had overall nucleotide sequence identity with DNAbeta-Ibaraki of 83%. Comparison of the nucleotide sequences with other begomoviruses revealed that Nara virus-1 and Nara virus-2 are strains of Honeysuckle yellow vein mosaic virus (HYVMV), hence named as HYVMV-Nara1 and HYVMV-Nara2, whereas Ibaraki virus was a strain of Tobacco leaf curl Japan virus (TbLCJV), designated as TbLCJV-Hs[Iba]. HYVMV-Nara1 and HYVMV-Nara2 have hybrid genomes, which are likely to have formed recombination between HYVMV and TbLCJV. TbLCJV-Hs[Iba] or HYVMV-Nara2 could infect and cause yellowing, leaf crinkling and stunting symptoms when partial tandem dimeric constructs were agroinoculated on tomato plants. However, in the presence of DNAbeta, both TbLCJV-Hs[Iba] or HYVMV-Nara2 produced more severe stunting symptoms in tomato plants. Therefore, these viruses along with their satellites are causal agents of tomato yellow dwarf disease in Japan, and honeysuckle acts as a potential reservoir host. Previously available evidence indicated that DNAbeta elements do not contain iteron sequences of their helper viruses; hence this is the first evidence that DNAbeta satellites have the iteron of their helper virus.

  17. 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.

  18. RNAi mediated gene silencing against betasatellite associated with Croton yellow vein mosaic begomovirus.

    PubMed

    Sahu, Anurag Kumar; Marwal, Avinash; Nehra, Chitra; Choudhary, Devendra Kumar; Sharma, Pradeep; Gaur, Rajarshi Kumar

    2014-11-01

    Plant viruses encode suppressors of posttranscriptional gene silencing, an adaptive antiviral defense responses that confines virus infection. Previously, we identified single-stranded DNA satellite (also known as DNA-β) of ~1,350 nucleotides in length associated with Croton yellow vein mosaic begomovirus (CYVMV) in croton plants. The expression of genes from DNA-β requires the begomovirus for packaged, replication, insect transmission and movement in plants. The present study demonstrates the effect of the βC1 gene on the silencing pathway as analysed by using both transgenic systems and transient Agrobacterium tumefaciens based delivery. Plants that carry an intron-hairpin construct covering the βC1 gene accumulated cognate small-interfering RNAs and remained symptom-free after exposure to CYVMV and its satellite. These results suggest that βC1 interferes with silencing mechanism.

  19. 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 ...

  20. Development and evaluation of ELISA and qRT-PCR for identification of Squash vein yellowing virus in cucurbits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enzyme linked-immunosorbent assay (ELISA) and quantitative reverse transcription-PCR (qRT-PCR) assays were developed for identification of Squash vein yellowing virus (SqVYV), the cause of viral watermelon vine decline. Both assays were capable of detecting SqVYV in a wide range of cucurbit hosts. ...

  1. 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 ...

  2. 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...

  3. Identification and characterization of citrus yellow vein clearing virus, a putative new member of the genus Mandarivirus.

    PubMed

    Loconsole, G; Onelge, N; Potere, O; Giampetruzzi, A; Bozan, O; Satar, S; De Stradis, A; Savino, V; Yokomi, R K; Saponari, M

    2012-12-01

    Molecular features and genomic organization were determined for Citrus yellow vein clearing virus (CYVCV), the putative viral causal agent of yellow vein clearing disease of lemon trees, reported in Pakistan, India, and more recently in Turkey and China. CYVCV isolate Y1 from Adana, Turkey, was used for deep sequencing analysis of the virus-induced small RNA fractions and for mechanical and graft inoculation of herbaceous and citrus indicator plants. A polyclonal antiserum was developed from CYVCV-Y1 purified from Phaseolus vulgaris and used in western blot assays to characterize the coat protein of CYVCV-Y1 and determine its serological relationship with related viruses. Contigs assembled from the Illumina sequenced short reads were used to construct the whole genome of Citrus yellow vein clearing virus (CYVCV), consisting in a positive-sense RNA of 7,529 nucleotides and containing six predicted open reading frames. The CYVCV genome organization and size resembled that of flexiviruses, and search for sequence homologies revealed that Indian citrus ringspot virus (ICRSV) (Mandarivirus, Alphaflexiviridae) is the most closely related virus. However, CYVCV had an overall nucleotide sequence identity of ≈74% with ICRSV. Although the two viruses were similar with regard to genome organization, viral particles, and herbaceous host range, CYVCV caused different symptoms in citrus and was serologically distinct from ICRSV. Primer pairs were designed and used to detect the virus by conventional and quantitative reverse transcription-polymerase chain reaction on yellow vein clearing symptomatic field trees as well as graft- and mechanically inoculated host plants. Collectively, these data suggest that CYVCV is the causal agent of yellow vein clearing disease and represents a new species in the genus Mandarivirus.

  4. Characterization of sequence elements from Malvastrum yellow vein betasatellite regulating promoter activity and DNA replication

    PubMed Central

    2012-01-01

    Background Many monopartite begomoviruses are associated with betasatellites, but only several promoters from which were isolated and studied. In this study, the βC1 promoter from Malvastrum yellow vein betasatellite (MYVB) was characterized and important sequence elements were identified to modulate promoter activity and replication of MYVB. Results A 991 nucleotide (nt) fragment upstream of the translation start site of the βC1 open reading frame of MYVB and a series of deletions within this fragment were constructed and fused to the β-glucuronidase (GUS) and green fluorescent protein (GFP) reporter genes, respectively. Agrobacterium-mediated transient expression assays showed that the 991 nt fragment was functional and that a 28 nt region (between −390 nt and −418 nt), which includes a 5′UTR Py-rich stretch motif, was important for promoter activity. Replication assays using Nicotiana benthamiana leaf discs and whole plants showed that deletion of the 5′UTR Py-rich stretch impaired viral satellite replication in the presence of the helper virus. Transgenic assays demonstrated that the 991 nt fragment conferred a constitutive expression pattern in transgenic tobacco plants and that a 214 nt fragment at the 3'-end of this sequence was sufficient to drive this expression pattern. Conclusion Our results showed that the βC1 promoter of MYVB displayed a constitutive expression pattern and a 5′UTR Py-rich stretch motif regulated both βC1 promoter activity and MYVB replication. PMID:23057573

  5. 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

  6. 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

    2014-01-14

    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.

  7. Molecular identification of Ageratum enation virus, betasatellite and alphasatellite molecules isolated from yellow vein diseased Amaranthus cruentus in India.

    PubMed

    Srivastava, Ashish; Raj, Shri Krishana; Kumar, Susheel; Snehi, Sunil Kumar; Kulshreshtha, Aditya; Hallan, Vipin; Pande, Sunil Sohanlal

    2013-12-01

    Natural occurrence of yellow vein disease on Amaranthus cruentus was observed at Lucknow, India in the year 2008. The causal virus was successfully transmitted through whiteflies (Bemisia tabaci) from diseased A. cruentus to healthy seedlings of A. cruentus and other test species which indicated begomovirus infection. The begomovirus DNA-A, betasatellite, and alphasatellite components associated with yellow vein disease were amplified by rolling circle amplification using Ø-29 DNA polymerase from diseased A. cruentus and characterized by their sequence analyses. The begomovirus DNA-A genome contained six ORFs: AV2 and AV1 in virion sense and AC3, AC2, AC1, and AC4 in complementary sense strand; and a non-translated intergenic region having the conserved geminiviral nonanucleotide sequence. The virus isolate showed 97-99% sequence identities and close phylogenetic relationships with various isolates of Ageratum enation virus (AgEV); therefore, the isolate under study was identified as AgEV. The beta- and alphasatellite molecules were also identified to be associated with the disease based on their high sequence identities and close phylogenetic relationships with the respective molecules reported worldwide. Co-infiltration of agro-infectious clones of AgEV DNA-A and its betasatellite DNA induced leaf curl and enation symptoms after 25-35 days on A. cruentus, Nicotiana benthamiana, and N. glutinosa plants. We report the association of AgEV, betasatellite and alphasatellite components with yellow vein disease of A. cruentus from India.

  8. Development of a VIGS vector based on the β-satellite DNA associated with bhendi yellow vein mosaic virus.

    PubMed

    Jeyabharathy, C; Shakila, H; Usha, R

    2015-01-02

    Bhendi yellow vein mosaic virus (BYMV) is a monopartite begomovirus with an associated β-satellite. βC1 ORF encoded by the β-satellite is the symptom determinant and a strong suppressor of post transcriptional gene silencing. To create a virus induced gene silencing vector based upon the β-satellite associated with BYVMV the βC1 ORF was replaced with multiple cloning sites. GFP transgene and plant endogenous genes Su, PDS, PCNA and AGO1 were cloned into β-satellite based VIGS vector. GFP expression was silenced in the GFP expressing transgenic 16c Nicotiana benthamiana plants infiltrated with VIGS vector carrying GFP gene inside. N. benthamiana plants infiltrated with the VIGS vector harboring the endogenous genes Su, PDS, PCNA and AGO1 produced the phenotypic symptoms yellowing of the veins, photobleaching of the veins, stunting of the plant and upward leaf curling, respectively. Real time PCR analyses revealed a reduction in the levels of the corresponding transgene or endogenous target mRNA. The β-satellite based VIGS vector was able to silence the target genes effectively. Hence, BYVMV β-satellite based VIGS vector can be used in functional genomics studies.

  9. Tobacco streak virus isolated from lettuce.

    PubMed

    Abtahi, F S; Khodai Motlagh, M

    2009-05-01

    Tobacco streak virus (TSV) is an ilarvirus with a worldwide distribution. This virus infects many plants and causes significant yield losses. In this study, 300 samples of lettuce were collected from lettuce fields in Tehran Province. Infected plants show symptoms such as: mosaic, vein clearing, vein necrosis, yellowing and leaf distortion. DAS-ELISA (Double Antibody Sandwich-ELISA) was used with a polyclonal antiserum against TSV. Five isolates (T1, T2, T3, T4 and T5), which are collected, respectively from Mohammad Abad (Karaj), Malek Abad (Karaj), Hashtgerd (Karaj), Tarand Balla (Varamin) and Deh mah sin (Pishva) were inoculated on 29 species of Cucurbitaceae, Amaranthaceae, Solanacea, Compositae, Leguminosae and Chenopodiacea. Chenopodium quinoa 6 days after inoculation showed necrotic local lesions. Gomphrena globosa 10 days after inoculation developed chlorotic local lesions. Systemic symptoms were produced in Datura stramonium. Phaseolus vulgaris cv. Red Kidney 5 days after inoculation developed necrotic local lesions. Nicotiana tabacum 7 days after inoculation showed necrotic and chlorotic local lesions. Nicotiana clevelandii 15 days after inoculation developed leaf distortion and vein necrosis. Lactuca sativa 10-15 days after inoculation developed leaf istortion and mosaic. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was performed using one primer pairs designed by DSMZ. An approximately 710 bp fragment was amplified with a specific primer.

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

    PubMed

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

    2013-03-01

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

  11. Cloning of the coat protein gene from beet necrotic yellow vein virus and its expression in sugar beet hairy roots.

    PubMed

    Ehlers, U; Commandeur, U; Frank, R; Landsmann, J; Koenig, R; Burgermeister, W

    1991-06-01

    Expression of the beet necrotic yellow vein virus (BNYVV) coat protein (CP) gene in transgenic sugar beet hairy roots was accomplished as a step towards CP-mediated virus resistance. A cDNA for the CP gene and its 5' terminal untranslated leader sequence was prepared from BNYVV RNA, using two oligodeoxynucleotides to prime the synthesis of both strands. Second-strand synthesis and amplification of the cDNA were done by Taq DNA polymerase chain reactions. Run-off transcripts of the cloned cDNA sequence were obtained and translated in vitro, yielding immunoreactive CP. A binary vector construction containing the CP gene under the control of the 35S promoter of cauliflower mosaic virus was prepared and used for Agrobacterium rhizogenes-mediated transformation of sugar beet tissue. Stable integration and expression of the CP gene in sugar beet hairy roots was demonstrated by Southern, Northern, and Western blot analysis, respectively.

  12. 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...

  13. 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.

  14. Quantitative detection of Cucumber vein yellowing virus in susceptible and partially resistant plants using real-time PCR.

    PubMed

    Picó, Belén; Sifres, Alicia; Nuez, Fernando

    2005-09-01

    A method for the detection of Cucumber vein yellowing virus (CVYV) that combines reverse transcription with real-time PCR (SYBR((R)) Green chemistry) was developed using specific primers designed from a nucleotide sequence of the RNA polymerase gene (NIb) conserved among all the available CVYV strains. This method provided a linear assay over five to six orders of magnitude and reproducibly detected titres as low as 10(3) molecules of the target CVYV cDNA. Real-time PCR gave reproducible results for the quantification of CVYV in young leaves of susceptible and resistant cucumber landraces after mechanical inoculation. Significant differences in the starting amount of target cDNA were found between the analyzed genotypes, indicating differences in viral accumulation that correlated to their different levels of resistance. Real-time PCR results validated our previous findings using slot-blot hybridization, the dominance of the strong resistance to CVYV displayed by C.sat 10, and provided improved reliability and sensitivity of detection. This method has great potential in resistance breeding for germplasm screening, characterization of resistance mechanisms and genetic studies.

  15. 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.

  16. 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.

  17. Analysis of sequences from field samples reveals the presence of the recently described pepper vein yellows virus (genus Polerovirus) in six additional countries.

    PubMed

    Knierim, Dennis; Tsai, Wen-Shi; Kenyon, Lawrence

    2013-06-01

    Polerovirus infection was detected by reverse transcription polymerase chain reaction (RT-PCR) in 29 pepper plants (Capsicum spp.) and one black nightshade plant (Solanum nigrum) sample collected from fields in India, Indonesia, Mali, Philippines, Thailand and Taiwan. At least two representative samples for each country were selected to generate a general polerovirus RT-PCR product of 1.4 kb length for sequencing. Sequence analysis of the partial genome sequences revealed the presence of pepper vein yellows virus (PeVYV) in all 13 samples. A 1990 Australian herbarium sample of pepper described by serological means as infected with capsicum yellows virus (CYV) was identified by sequence analysis of a partial CP sequence as probably infected with a potato leaf roll virus (PLRV) isolate.

  18. Efficient dsRNA-mediated transgenic resistance to Beet necrotic yellow vein virus in sugar beets is not affected by other soilborne and aphid-transmitted viruses.

    PubMed

    Lennefors, Britt-Louise; van Roggen, Petra M; Yndgaard, Flemming; Savenkov, Eugene I; Valkonen, Jari P T

    2008-04-01

    Rhizomania caused by Beet necrotic yellow vein virus (BNYVV) is one of the most devastating sugar beet diseases. Sugar beet plants engineered to express a 0.4 kb inverted repeat construct based on the BNYVV replicase gene accumulated the transgene mRNA to similar levels in leaves and roots, whereas accumulation of the transgene-homologous siRNA was more pronounced in roots. The roots expressed high levels of resistance to BNYVV transmitted by the vector, Polymyxa betae. Resistance to BNYVV was not decreased following co-infection of the plants with Beet soil borne virus and Beet virus Q that share the same vector with BNYVV. Similarly, co-infection with the aphid-transmitted Beet mild yellowing virus, Beet yellows virus (BYV), or with all of the aforementioned viruses did not affect the resistance to BNYVV, while they accumulated in roots. These viruses are common in most of the sugar beet growing areas in Europe and world wide. However, there was a competitive interaction between BYV and BMYV in sugar beet leaves, as infection with BYV decreased the titres of BMYV. Other interactions between the viruses studied were not observed. The results suggest that the engineered resistance to BNYVV expressed in the sugar beets of this study is efficient in roots and not readily compromised following infection of the plants with heterologous viruses.

  19. Streak camera meeting summary

    SciTech Connect

    Dolan, Daniel H.; Bliss, David E.

    2014-09-01

    Streak cameras are important for high-speed data acquisition in single event experiments, where the total recorded information (I) is shared between the number of measurements (M) and the number of samples (S). Topics of this meeting included: streak camera use at the national laboratories; current streak camera production; new tube developments and alternative technologies; and future planning. Each topic is summarized in the following sections.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Identification of amino acids of the beet necrotic yellow vein virus p25 protein required for induction of the resistance response in leaves of Beta vulgaris plants.

    PubMed

    Chiba, Soutaro; Miyanishi, Masaki; Andika, Ida Bagus; Kondo, Hideki; Tamada, Tetsuo

    2008-05-01

    The RNA3-encoded p25 protein of beet necrotic yellow vein virus (BNYVV) is responsible for the production of rhizomania symptoms of sugar beet roots (Beta vulgaris subsp. vulgaris). Here, it was found that the presence of the p25 protein is also associated with the resistance response in rub-inoculated leaves of sugar beet and wild beet (Beta vulgaris subsp. maritima) plants. The resistance phenotype displayed a range of symptoms from no visible lesions to necrotic or greyish lesions at the inoculation site, and only very low levels of virus and viral RNA accumulated. The susceptible phenotype showed large, bright yellow lesions and developed high levels of virus accumulation. In roots after Polymyxa betae vector inoculation, however, no drastic differences in virus and viral RNA accumulation levels were found between plants with susceptible and resistant phenotypes, except at an early stage of infection. There was a genotype-specific interaction between BNYVV strains and two selected wild beet lines (MR1 and MR2) and sugar beet cultivars. Sequence analysis of natural BNYVV isolates and site-directed mutagenesis of the p25 protein revealed that 3 aa residues at positions 68, 70 and 179 are important in determining the resistance phenotype, and that host-genotype specificity is controlled by single amino acid changes at position 68. The mechanism of the occurrence of resistance-breaking BNYVV strains is discussed.

  5. Arabian Slope Streaks

    NASA Technical Reports Server (NTRS)

    2003-01-01

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

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

  6. 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.

  7. 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.

  8. Expression of the Beet necrotic yellow vein virus p25 protein induces hormonal changes and a root branching phenotype in Arabidopsis thaliana.

    PubMed

    Peltier, Claire; Schmidlin, Laure; Klein, Elodie; Taconnat, Ludivine; Prinsen, Els; Erhardt, Mathieu; Heintz, Dimitri; Weyens, Guy; Lefebvre, Marc; Renou, Jean-Pierre; Gilmer, David

    2011-06-01

    The RNA-3-encoded p25 protein was previously characterized as one of the major symptom determinants of the Beet necrotic yellow vein virus. Previous analyses reported the influence of the p25 protein in root proliferation phenotype observed in rhizomania disease on infected sugar beets (Beta vulgaris). A transgenic approach was developed, in which the p25 protein was constitutively expressed in Arabidopsis thaliana Columbia (Col-0) ecotype in order to provide new clues as to how the p25 protein might promote alone disease development and symptom expression. Transgenic plants were characterized by Southern blot and independent lines carrying single and multiple copies of the transgene were selected. Mapping of the T-DNA insertion was performed on the monocopy homozygote lines. P25 protein was localized both in the nucleus and in the cytoplasm of epidermal and root cells of transgenic plants. Although A. thaliana was not described as a susceptible host for BNYVV infection, abnormal root branching was observed on p25 protein-expressing A. thaliana plants. Moreover, these transgenic plants were more susceptible than wild-type plants to auxin analog treatment (2,4-D) but more resistant to methyl jasmonate (MeJA), abscisic acid (ABA) and to lesser extend to salicylic acid (SA). Hormonal content assays measuring plant levels of auxin (IAA), jasmonate (JA) and ethylene precursor (ACC) revealed major hormonal changes. Global transcript profiling analyses on roots displayed differential gene expressions that could corroborate root branching phenotype and stress signaling modifications.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Quantitative and Qualitative Involvement of P3N-PIPO in Overcoming Recessive Resistance against Clover Yellow Vein Virus in Pea Carrying the cyv1 Gene

    PubMed Central

    Choi, Sun Hee; Hagiwara-Komoda, Yuka; Atsumi, Go; Shimada, Ryoko; Hisa, Yusuke; Naito, Satoshi

    2013-01-01

    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

  14. 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.

  15. 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

  16. Streak speckle velocimetry

    NASA Astrophysics Data System (ADS)

    Re Calegari, Gabriele; Ferri, Fabio

    2014-01-01

    We present a method for fluid velocimetry based on a single-exposure analysis of the streak speckle pattern generated by sub-micron tracking particles illuminated with coherent light. It works in real-time and provides two dimensional velocity mappings in the direction orthogonal to the optical axis, independently of particle concentration and size. It is immune of any spurious light acting as undesired heterodyne signal and can probe velocities much higher (˜three orders of magnitude) than methods based on double-exposure analysis. The method has been tested by using rigid diffusers of different heterodyne strength and applied to map the flow of a confined fluid.

  17. 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…

  18. 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

  19. P3N-PIPO, a Frameshift Product from the P3 Gene, Pleiotropically Determines the Virulence of Clover Yellow Vein Virus in both Resistant and Susceptible Peas

    PubMed Central

    Suzuki, Haruka; Miyashita, Yuri; Choi, Sun Hee; Hisa, Yusuke; Rihei, Shunsuke; Shimada, Ryoko; Jeon, Eun Jin; Abe, Junya; Uyeda, Ichiro

    2016-01-01

    ABSTRACT Peas carrying the cyv1 recessive resistance gene are resistant to clover yellow vein virus (ClYVV) isolates No.30 (Cl-No.30) and 90-1 (Cl-90-1) but can be infected by a derivative of Cl-90-1 (Cl-90-1 Br2). The main determinant for the breaking of cyv1 resistance by Cl-90-1 Br2 is P3N-PIPO produced from the P3 gene via transcriptional slippage, and the higher level of P3N-PIPO produced by Cl-90-1 Br2 than by Cl-No.30 contributes to the breaking of resistance. Here we show that P3N-PIPO is also a major virulence determinant in susceptible peas that possess another resistance gene, Cyn1, which does not inhibit systemic infection with ClYVV but causes hypersensitive reaction-like lethal systemic cell death. We previously assumed that the susceptible pea cultivar PI 226564 has a weak allele of Cyn1. Cl-No.30 did not induce cell death, but Cl-90-1 Br2 killed the plants. Our results suggest that P3N-PIPO is recognized by Cyn1 and induces cell death. Unexpectedly, heterologously strongly expressed P3N-PIPO of Cl-No.30 appears to be recognized by Cyn1 in PI 226564. The level of P3N-PIPO accumulation from the P3 gene of Cl-No.30 was significantly lower than that of Cl-90-1 Br2 in a Nicotiana benthamiana transient assay. Therefore, Cyn1-mediated cell death also appears to be determined by the level of P3N-PIPO. The more efficiently a ClYVV isolate broke cyv1 resistance, the more it induced cell death systemically (resulting in a loss of the environment for virus accumulation) in susceptible peas carrying Cyn1, suggesting that antagonistic pleiotropy of P3N-PIPO controls the resistance breaking of ClYVV. IMPORTANCE Control of plant viral disease has relied on the use of resistant cultivars; however, emerging mutant viruses have broken many types of resistance. Recently, we revealed that Cl-90-1 Br2 breaks the recessive resistance conferred by cyv1, mainly by accumulating a higher level of P3N-PIPO than that of the nonbreaking isolate Cl-No.30. Here we show that a

  20. Varicose Veins

    MedlinePlus

    ... has surface (superficial) veins that are connected to deep veins by bridging (perforator) veins. Unlike arteries, which ... the valve leaflets and can develop in the deep, perforator, or superficial veins. View this table: View ...

  1. 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.

  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. 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.

  4. 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.

  5. 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

  6. Gated SIT Vidicon Streak Tube

    NASA Astrophysics Data System (ADS)

    Dunbar, D. L.; Yates, G. J.; Black, J. P.

    1986-01-01

    A recently developed prototype streak tube designed to produce high gain and resolution by incorporating the streak and readout functions in one envelope thereby minimizing photon-to-charge transformations and eliminating external coupling losses is presented. The tube is based upon a grid-gated Silicon-Intensified-Target Vidicon (SITV) with integral Focus Projection Scan (FPS) TV readout. Demagnifying electron optics (m=0.63) in the image section map the 40-mm-diameter photocathode image unto a 25-mm-diameter silicon target where gains >= 103 are achieved with only 10 KV accelerating voltage. This is compared with much lower gains (~ 50) at much higher voltages (~ 30 KV) reported for streak tubes using phosphor screens. Because SIT technology is well established means for electron imaging in vacuum, such fundamental problems as "backside thinning" required for electron imaging unto CCDs do not exist. The high spatial resolution (~ 30 1p/mm), variable scan formats, and high speed electrostatic deflection (250 mm2 areas are routinely rastered with 256 scan lines in 1.6 ms) available from FPS readout add versatility not available in CCD devices. Theoretical gain and spatial resolution for this design (developed jointly by Los Alamos National Laboratory and General Electric Co.) are compared with similar calculations and measured data obtained for RCA 73435 streaks fiber optically coupled to (1) 25-mm-diameter SIT FPS vidicons and (2) 40-mm-diameter MCPTs (proximity-focused microchannel plate image intensifier tubes) fiber optically coupled to 18-mm-diameter Sb2S3 FPS vidicons. Sweep sensitivity, shutter ratio, and record lengths for nanosecond duration (20 to 200 ns) streak applications are discussed.

  7. 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.

  8. Spider Veins

    MedlinePlus

    ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ...

  9. Vein Problems Related to Varicose Veins

    MedlinePlus

    ... varicose veins include venous lakes, reticular veins, and hemorrhoids. Venous lakes are varicose veins that appear on ... flat blue veins often seen behind the knees. Hemorrhoids are varicose veins in and around the anus. ...

  10. Laminar streak enhancement using streamwise grooves

    NASA Astrophysics Data System (ADS)

    Martel, Carlos; Martín, Juan Ángel

    2011-11-01

    Laminar streak promotion in a flat plate boundary layer results in an increase of the stability of the Tollmien-Schlichting waves with respect to that of the 2D Blasius profile. This stabilization delays the laminar-turbulent transition, increasing the laminar phase of the flow. The stabilization effect is stronger for higher streak amplitudes, and therefore simple ways of generating high amplitude stable streaks are sought to be used as boundary layer flow control methods. In a recent experiment [Tallamelli & Franson,AIAA 2010-4291] high amplitude stable steady streaks have been produced using Miniature Vortex Generators (MGVs), where one array of MGVs is used to excite the streak and a second array is used downstream to enhance their amplitude. In this presentation we numerically explore the possibility of enhancing the streaks using a different passive mechanism: streamwise grooves carved in the plate. We will present some numerical simulations for different values of the spanwise period of the streaks and of the grooves, and we will show the combinations that provide maximum streak amplitude.

  11. 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

  12. Time-resolved photoemission using attosecond streaking

    NASA Astrophysics Data System (ADS)

    Nagele, S.; Pazourek, R.; Wais, M.; Wachter, G.; Burgdörfer, J.

    2014-04-01

    We theoretically study time-resolved photoemission in atoms as probed by attosecond streaking. We review recent advances in the study of the photoelectric efect in the time domain and show that the experimentally accessible time shifts can be decomposed into distinct contributions that stem from the feld-free photoionization process itself and from probe-field induced corrections. We perform accurate quantum-mechanical as well as classical simulations of attosecond streaking for efective one-electron systems and determine all relevant contributions to the time delay with attosecond precision. In particular, we investigate the properties and limitations of attosecond streaking for the transition from short-ranged potentials (photodetachment) to long-ranged Coulomb potentials (photoionization). As an example for a more complex system, we study time-resolved photoionization for endohedral fullerenes A@C60 and discuss how streaking time shifts are modifed due to the interaction of the C60 cage with the probing infrared streaking field.

  13. Yellow Fever

    MedlinePlus

    ... on symptoms, physical findings, laboratory testing, and travel history, including the possibility of exposure to infected mosquitoes. There is no specific treatment for yellow fever; care is based on symptoms. Steps to prevent yellow fever virus infection ... and ...

  14. 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...

  15. Topographic measurements of slope streaks on Mars

    NASA Astrophysics Data System (ADS)

    Brusnikin, Eugene S.; Kreslavsky, Mikhail A.; Zubarev, Anatoly E.; Patratiy, Vyacheslav D.; Krasilnikov, Sergey S.; Head, James W.; Karachevtseva, Irina P.

    2016-11-01

    Slope streaks are enigmatic, actively forming albedo features occurring on slopes in high-albedo, low-thermal-inertia, dust-rich equatorial regions on Mars. They are a specifically martian phenomenon with no direct analogs on the Earth. Their morphology suggests that the streaks are initiated at their upslope tips and propagate down to their termini; however, the physical mechanism of their formation is uncertain. We performed a large series of measurements of slopes associated with slope streaks using stereo pairs of high-resolution orbital images obtained by HiRISE camera and generated several digital elevation models for selected streaks. We found that: (1) slopes at the upslope streak tips range widely, however, there is a strong indication that streaks can be initiated only on slopes steeper than ∼20°; (2) slopes of the streak termini show an even wider range, with some streaks terminating at slopes as steep as their tips, while others propagate all the way down to horizontal surfaces; (3) the streaks can propagate stably for long (many hundreds of meters) distances and can turn, following the topographic gradient on ∼10°-15° slopes; (4) no uphill propagation of streaks is detected over baselines of tens of meters; (5) the slope streaks often propagate over 1-2 m high obstacles and can climb 1-2 m uphill over short (meters) distances. We used these findings to assess the viability of two classes of hypotheses about slope streak formation mechanisms proposed earlier: 1) "dry", some kind of run-away avalanche-like dry granular flow, and 2) "wet", some kind of run-away propagation of a front of percolating brines in the shallow subsurface. No specific observation unambiguously proves or rejects either of the two mechanisms. Several of our findings are readily explained by the "dry" mechanism and cannot be easily explained with any kind of "wet" mechanism, while other findings are closely consistent with the "wet" mechanism and are difficult to reconcile

  16. 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.

  17. Ozone, jet streaks and severe weather

    NASA Technical Reports Server (NTRS)

    Sechrist, Frank S.; Petersen, Ralph A.; Brill, Keith F.; Krueger, Arlin J.; Uccellini, Louis W.

    1987-01-01

    Data from three independent observing platforms are synthesized to study the role of jet streaks in severe weather. The three data types are: conventional radiosondes; 6.7 micron water vapor imagery from the GOES satellite; and total ozone imagery from Nimbus 7. Diagnoses are then made of potential vorticity, mid-tropospheric moisture, and total ozone at and below the level of jet streaks. Potential vorticity and total ozone distributions are both tracers of stratospheric air. Theoretically, both should respond to the transverse, vertical circulations expected in the vicinity of jet streaks. Both should increase due to the sinking above the left front quadrant of the streaks. Moisture, on the other hand, increases in the ascent under the left front quadrant. This study shows striking agreement between the three parameters independently observed from three different observing platforms. Moreover, the three severe weather case studies suggest a unique distribution of ozone, potential vorticity, and mid-tropospheric moisture relative to a jet streak. This, in turn, led to the creation of a new ozone/jet streak model which shows that the total ozone distribution provides a signature in the vicinity of jet streaks and permits identification of areas most likely to experience severe weather at a later time. The value of such observations to operational forecasting is discussed.

  18. 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.

  19. Streak instability in viscoelastic Couette flow

    NASA Astrophysics Data System (ADS)

    Biancofiore, Luca; Brandt, Luca; Zaki, Tamer

    2015-11-01

    The secondary instability of streaks and transition to turbulence in viscoelastic Couette flow are studied using direct numerical simulations (DNS). Viscoelasticity is modeled using the FENE-P constitutive equations, and both the polymer concentration and Weissenberg number are varied in order to assess their effect on transition at moderate Reynolds number, Re = 400 .The base streaks are obtained from nonlinear simulations of the Couette flow response to a streamwise vortex, and can be classified as quasi-Newtonian streaks according to the terminology introduced by Page & Zaki (2014). At every streak amplitude of interest, harmonic forcing is introduced to trigger the secondary instability and breakdown to turbulence. The critical amplitude of this forcing decreases at higher Weissenberg number and also with increasing polymer concentration. The results demonstrate the destabilizing effect of elasticity at moderate Reynolds numbers.

  20. Sclerotherapy of Varicose Veins and Spider Veins

    MedlinePlus

    ... Index A-Z Sclerotherapy of Varicose Veins and Spider Veins Sclerotherapy uses injections from a very fine, ... Sclerotherapy? What is Sclerotherapy of Varicose Veins and Spider Veins? Sclerotherapy is a minimally invasive treatment used ...

  1. 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.

  2. Yellow fever.

    PubMed

    Monath, Thomas P; Vasconcelos, Pedro F C

    2015-03-01

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

  3. Varicose Veins and Spider Veins

    MedlinePlus

    ... are sold in medical supply and drugstores. Prescription-strength gradient compression hose, which offer the greatest amount ... the face. Exercise regularly to improve your leg strength, circulation, and vein strength. Focus on exercises that ...

  4. Gullies and Streaks on Crater wall Kaiser

    NASA Technical Reports Server (NTRS)

    2002-01-01

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

  5. 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 ...

  6. 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

  7. Yellow fever

    MedlinePlus

    ... liver, and kidney. Bleeding disorders, seizures, coma, and delirium may also occur. Symptoms may include: Fever, headache, ... tongue Yellow skin and eyes (jaundice) Decreased urination Delirium Irregular heartbeats (arrhythmias) Bleeding (may progress to hemorrhage) ...

  8. Varicose Veins

    MedlinePlus

    ... Wearing loose clothing and avoiding long periods of standing can also help. If varicose veins are painful or you don't like the way they look, your doctor may recommend procedures to remove them. NIH: National Heart, Lung, and Blood Institute

  9. 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.

  10. Preventing Deep Vein Thrombosis

    MedlinePlus

    ... Education & Events Advocacy For Patients About ACOG Preventing Deep Vein Thrombosis Home For Patients Search FAQs Preventing ... Vein Thrombosis FAQ174, August 2011 PDF Format Preventing Deep Vein Thrombosis Women's Health What is deep vein ...

  11. Wind Streaks on Venus: Clues to Atmospheric Circulation

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

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

  12. Streaking Artifact Reduction for Quantitative Susceptibility Mapping of Sources with Large Dynamic Range

    PubMed Central

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

    2015-01-01

    Quantitative susceptibility mapping (QSM) is a novel MRI technique for measuring tissue magnetic susceptibility in 3D. While there are numerous algorithms developed to solve this ill-posed inverse problem, estimating susceptibility maps with a wide range of values is still problematic. In cases such as large veins, contrast agent uptake, and intracranial hemorrhages, extreme susceptibility values in focal areas cause severe streaking artifacts. To enable the reduction of these artifacts while preserving subtle susceptibility contrast, a two-level QSM reconstruction algorithm (STAR-QSM) was developed in this study by tuning a regularization parameter to automatically reconstruct both large and small susceptibility values. Compared to current state-of-the-art QSM methods such as iLSQR, STAR-QSM significantly reduced streaking artifacts while preserving sharp boundaries for blood vessels of mouse brains in vivo and fine anatomical details of high resolution mouse brains ex vivo. Brain image data from patients with cerebral hematoma and multiple sclerosis further illustrated the superiority of this method in reducing streaking artifacts caused by large susceptibility sources while maintaining sharp anatomical details. STAR-QSM is implemented in STI Suite, a comprehensive shareware for susceptibility imaging and quantification. PMID:26313885

  13. 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.

  14. Streaking of shake-up ionization

    NASA Astrophysics Data System (ADS)

    Pazourek, Renate; Nagele, Stefan; Feist, Johannes; Kaltenbäck, Andreas; Persson, Emil; Schneider, Barry I.; Collins, Lee A.; Burgdörfer, Joachim

    2010-03-01

    We investigate whether an apparent ``time delay'' between electrons ionized by an attosecond XUV pulse with and without shake-up excitation of the remaining ion can be extracted using XUV-IR streaking setups. The classical interpretation of attosecond streaking states that the release time of an electron can be directly mapped to the momentum shift which the electron acquires from the IR pulse. However, detailed quantum mechanical investigations show that the ionization and shake-up process itself are modified by the IR field, leading to additional momentum shifts of the ionized electrons which are not related to a real ``time delay.'' We address this problem for the helium atom for which we solve the full time-dependent Schr"odinger equation including all correlation effects.

  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 ... How can I prevent yellow fever?Yellow fever vaccine can prevent yellow fever. ... only at designated vaccination centers. After getting the vaccine, you ...

  16. 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.

  17. Understanding baseball team standings and streaks

    NASA Astrophysics Data System (ADS)

    Sire, C.; Redner, S.

    2009-02-01

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

  18. Spider Vein Removal

    MedlinePlus

    Spider veins: How are they removed? I have spider veins on my legs. What options are available ... M.D. Several options are available to remove spider veins — thin red lines or weblike networks of ...

  19. What Causes Varicose Veins?

    MedlinePlus

    ... weak or damaged, blood can back up and pool in your veins. This causes the veins to ... pressure in your veins due to overweight or obesity or pregnancy. Rate This Content: NEXT >> Updated: February ...

  20. The mevalonate pathway regulates primitive streak formation via protein farnesylation

    PubMed Central

    Okamoto-Uchida, Yoshimi; Yu, Ruoxing; Miyamura, Norio; Arima, Norie; Ishigami-Yuasa, Mari; Kagechika, Hiroyuki; Yoshida, Suguru; Hosoya, Takamitsu; Nawa, Makiko; Kasama, Takeshi; Asaoka, Yoichi; Alois, Reiner Wimmer; Elling, Ulrich; Penninger, Josef M.; Nishina, Sachiko; Azuma, Noriyuki; Nishina, Hiroshi

    2016-01-01

    The primitive streak in peri-implantation embryos forms the mesoderm and endoderm and controls cell differentiation. The metabolic cues regulating primitive streak formation remain largely unknown. Here we utilised a mouse embryonic stem (ES) cell differentiation system and a library of well-characterised drugs to identify these metabolic factors. We found that statins, which inhibit the mevalonate metabolic pathway, suppressed primitive streak formation in vitro and in vivo. Using metabolomics and pharmacologic approaches we identified the downstream signalling pathway of mevalonate and revealed that primitive streak formation requires protein farnesylation but not cholesterol synthesis. A tagging-via-substrate approach revealed that nuclear lamin B1 and small G proteins were farnesylated in embryoid bodies and important for primitive streak gene expression. In conclusion, protein farnesylation driven by the mevalonate pathway is a metabolic cue essential for primitive streak formation. PMID:27883036

  1. Picosecond x-ray streak cameras

    NASA Astrophysics Data System (ADS)

    Averin, V. I.; Bryukhnevich, Gennadii I.; Kolesov, G. V.; Lebedev, Vitaly B.; Miller, V. A.; Saulevich, S. V.; Shulika, A. N.

    1991-04-01

    The first multistage image converter with an X-ray photocathode (UMI-93 SR) was designed in VNIIOFI in 1974 [1]. The experiments carried out in IOFAN pointed out that X-ray electron-optical cameras using the tube provided temporal resolution up to 12 picoseconds [2]. The later work has developed into the creation of the separate streak and intensifying tubes. Thus, PV-003R tube has been built on base of UMI-93SR design, fibre optically connected to PMU-2V image intensifier carrying microchannel plate.

  2. 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

  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. GHz modulation detection using a streak camera: Suitability of streak cameras in the AWAKE experiment

    NASA Astrophysics Data System (ADS)

    Rieger, K.; Caldwell, A.; Reimann, O.; Muggli, P.

    2017-02-01

    Using frequency mixing, a modulated light pulse of ns duration is created. We show that, with a ps-resolution streak camera that is usually used for single short pulse measurements, we can detect via an FFT detection approach up to 450 GHz modulation in a pulse in a single measurement. This work is performed in the context of the AWAKE plasma wakefield experiment where modulation frequencies in the range of 80-280 GHz are expected.

  5. Streak Camera 101: Visualizing Charged-Particle Beam Dynamics

    NASA Astrophysics Data System (ADS)

    Yang, Bingxin

    2006-11-01

    Radiation generated by high-energy particle beams such as optical transition radiation (OTR) and optical synchrotron radiation (OSR) is widely used to characterize the beam properties. It has enabled dual-sweep streak cameras to visualize charged-particle beam dynamics. In this introductory paper, we will discuss properties of dual-sweep streak cameras and basic optics systems for imaging charged-particle bunches at different projection angles to produce top view, side view, and front view. Examples will be used to illustrate the beam dynamics that streak images reveal. We will also discuss practical considerations of optical transport line design to preserve spatial and temporal resolution of the camera system.

  6. 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.

  7. Deep Vein Thrombosis

    MedlinePlus

    ... vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem in the lung, called a pulmonary embolism. Sitting still for a long time can make ...

  8. Deep vein thrombosis - discharge

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000027.htm Deep vein thrombosis - discharge To use the sharing features ... page, please enable JavaScript. You were treated for deep vein thrombosis ( DVT ). This is a condition in ...

  9. Varicose vein stripping

    MedlinePlus

    ... noninvasive treatment Varicose veins Venous insufficiency Patient Instructions Surgical wound care - open Varicose veins - what to ask your doctor Review Date 6/6/2016 ... Interventional Radiology & Surgical Critical Care, Philadelphia, PA. Review provided by VeriMed ...

  10. Focus on Varicose Veins

    MedlinePlus

    ... work- ing properly or have evidence of reflux. Measurement of the venous function of the leg may ... Vein stripping was the traditional treatment for bad values in the veins however it is rarely used ...

  11. 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

  12. 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

  13. 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.

  14. 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

  15. Shielding a streak camera from hard x rays

    NASA Astrophysics Data System (ADS)

    Schneider, M. B.; Sorce, C.; Loughman, K.; Emig, J.; Bruns, C.; Back, C.; Bell, P. M.; Compton, S.; Hargrove, D.; Holder, J. P.; Landen, O. L.; Perry, T. S.; Shepherd, R.; Young, B. K.

    2004-10-01

    The targets used in the hot halfraum campaign at OMEGA create many hot electrons, which result in a large flux of hard x rays. The hard x rays produce a high background in the streak camera. The background was significantly reduced by wrapping the streak camera with a high-Z material; in this case, 1/8 in. of Pb. The large hard x-ray flux also adds noise to images from framing cameras which use charge-coupled devices.

  16. 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.

  17. Streak instability induced by bedload diffusion

    NASA Astrophysics Data System (ADS)

    Abramian, Anaïs; Seizilles, Grégoire; Devauchelle, Olivier; Lajeunesse, Eric

    2016-04-01

    The bed of an alluvial river is made of the sediment it transports. Its shape and size are controlled mostly by bedload transport which, at first order, entrains sediment grains along the flow. Gravity also pulls the moving grains towards the center of the channel, thus eroding the banks continually (Parker 1978). However, laboratory observations show that, due to the bed roughness, the trajectory of a transported grain fluctuates in the transverse direction (Seizilles et al. 2014). The bedload layer is therefore a collection of random walkers which diffuse towards the less active areas of the bed. In a river at equilibrium, bedload diffusion counteracts gravity to maintain the banks. If an initially flat bed of sediment is perturbed with longitudinal streaks, the flow-induced shear stress is weaker where the flow is shallower. Therefore, we expect bedload diffusion to induce a flux of sediment towards the crests of the perturbation. This positive feedback induces an instability which can generate new channels. We suggest that this mechanism could explain the transition from a single-thread river to a braided one.

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

    PubMed

    Jiang, Zhuocheng; Guo, Baoping

    2014-09-10

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

  19. Visual and infrared observations of wind streaks on Mars

    NASA Technical Reports Server (NTRS)

    Peterfreund, A. R.

    1981-01-01

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

  20. Sea surface wind streaks in spaceborne synthetic aperture radar imagery

    NASA Astrophysics Data System (ADS)

    Zhao, Yuan; Li, Xiao-Ming; Sha, Jin

    2016-09-01

    Wind streaks are often observed in Synthetic aperture radar (SAR) images. They are used to determine the sea surface wind direction for sea surface wind field retrievals. It is generally understood that visible wind streaks are caused by roll vortices in the marine atmospheric boundary layer. In this study, 227 X-band spaceborne SAR images of TerraSAR-X and TanDEM-X acquired from the three FiNO platforms in the North Sea and Baltic Sea were thoroughly analyzed for a comprehensive understanding of the manifestation of wind streaks in SAR images. Approximately 48.0% of the 227 SAR images displayed wind streaks, among which 67.3%, 20.0%, and 12.7% occurred under unstable, neutral, and stable atmospheric conditions, respectively. The proportions indicate that wind streaks are more likely to be generated from thermal convection. Further investigations suggest that the inflection point and the wind shear may be essential for the appearance of wind streaks in SAR images under stable atmospheric conditions.

  1. 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

  2. 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

  3. Vein of Galen Aneurysms

    PubMed Central

    Komiyama, M.; Nakajima, H.; Nishikawa, M.; Yamanaka, K.; Iwai, Y.; Yasui, T.; Morikawa, T.; Kitano, S.; Sakamoto, H.; Nishio, A.

    2001-01-01

    Summary Eleven patients with so-called “vein of Galen aneurysms ” are reported, six of whom presented with vein of Galen aneurysmal malformations (four with choroidal type and two with mural type malformations). The remaining five patients presented with vein of Galen aneurysmal dilatations secondarily due to an arteriovenous malformation in one patient, an arteriovenous fistula in another, dural arteriovenous fistulas in two patients, and a varix in another. Treatments for these patients were individualised with consideration given to the clinical manifestations and the angioarchitecture of their lesions. Endovascular intervention played a critical role in the treatment of these vein of Galen aneurysms. PMID:20663385

  4. 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.

  5. Unsteady analysis of hot streak migration in a turbine stage

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel J.; Davis, Roger L.; Edwards, David E.; Madavan, Nateri K.

    1990-01-01

    Two- and three-dimensional Navier-Stokes analyses are used to predict unsteady viscous rotor-stator interacting flow in the presence of a combustor hot streak. Predicted results are presented for a two-dimensional three-stator/four-rotor, a two-dimensional one-stator/one-rotor, and a three-dimensional one-stator/one-rotor simulation of hot streak migration through a turbine stage. Comparison of these results with experimental data demonstrates the capability of the three-dimensional procedure to capture most of the flow physics associated with hot streak migration including the effects of combustor hot streaks on turbine rotor surface temperatures. It is noted that blade count ratio has little effect on predicted time-averaged surface pressure and temperature distributions, but a substantial effect on the unsteady flow characteristics. It is shown that high-temperature hot streak fluid accumulates on the pressure surface of the rotor blades, resulting in a high time-averaged surface temperature 'hot spots'.

  6. 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

  7. 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.

  8. Support for varicose veins.

    PubMed Central

    Fentem, P H; Goddard, M; Gooden, B A

    1976-01-01

    A method has been devised to allow reliable comparison of different strengths and constructions of support hosiery. Five garments were evaluated for the compression they exerted on the leg and their ability to limit the distension of a model varicose vein. Stockings and tights which provide modest compression can achieve worthwhile control of vein distension. PMID:1247807

  9. Prepancreatic preduodenal portal vein.

    PubMed

    Lal, N S; Kuruvila, A P; Natesh, P B; Koshy, M M; Anandakumar, M

    1992-10-01

    We report a 17 year old girl with prepancreatic and preduodenal portal vein. She presented with recurrent vomiting. Barium study revealed malrotation of the gut. Laparotomy confirmed malrotation of the gut with a prepancreatic and preduodenal portal vein. The patient is asymptomatic after gastrojejunostomy and vagotomy.

  10. Performance of Laser Megajoule's x-ray streak camera

    NASA Astrophysics Data System (ADS)

    Zuber, C.; Bazzoli, S.; Brunel, P.; Burillo, M.; Fronty, J. P.; Gontier, D.; Goulmy, C.; Moreau, I.; Oudot, G.; Rubbelynck, C.; Soullié, G.; Stemmler, P.; Trosseille, C.

    2016-11-01

    A prototype of a picosecond x-ray streak camera has been developed and tested by Commissariat à l'Énergie Atomique et aux Énergies Alternatives to provide plasma-diagnostic support for the Laser Megajoule. We report on the measured performance of this streak camera, which almost fulfills the requirements: 50-μm spatial resolution over a 15-mm field in the photocathode plane, 17-ps temporal resolution in a 2-ns timebase, a detection threshold lower than 625 nJ/cm2 in the 0.05-15 keV spectral range, and a dynamic range greater than 100.

  11. 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.

  12. A wide dynamic range x-ray streak camera system

    SciTech Connect

    Niu Lihong; Yang Qinlao; Niu Hanben; Liao Hua; Zhou Junlan; Ding Yunkun

    2008-02-15

    An x-ray streak camera with wide dynamic range and a large slit photocathode of 30 mm length has been developed and calibrated. In order to achieve wide dynamic range, a conventional streak tube has been improved and the camera system has been designed without microchannel plate electron amplifier. As a result, a dynamic range of 922 is achieved in a single shot mode with laser pulse of 30 ps (full width at half maximum) at time resolution of better than 31 ps.

  13. How Are Varicose Veins Diagnosed?

    MedlinePlus

    ... injected into your veins. The dye outlines your veins on x-ray images. An angiogram can help your doctor confirm whether you have varicose veins or another condition. Rate This Content: NEXT >> Updated: ...

  14. 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.

  15. Wheat streak mosaic virus resistance in eight wheat germplasm lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat Streak Mosaic Virus (WSMV) disease is an important disease in wheat. Use of resistant cultivars is the most effective approach to reduce the yield losses caused by the disease. To identify new sources of resistance to WSMV, eight resistant wheat lines that were selected based on the results fr...

  16. 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.

  17. 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.

  18. Reliable and repeatable characterization of optical streak cameras.

    PubMed

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

    2008-10-01

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

  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. Attosecond streaking of correlated two-electron transitions

    NASA Astrophysics Data System (ADS)

    Pazourek, Renate; Nagele, Stefan; Feist, Johannes; Burgdörfer, Joachim

    2012-06-01

    Attosecond streaking is one of the most fundamental processes in attosecond science allowing for a mapping of temporal information to the energy domain. For the measurement of the release time of electrons in atomic photoemission a time-resolution on the sub-100 attosecond time scale could be achieved [Science 328, 1658 (2010)]. The measured time shifts contain timing (or spectral phase) information associated with the Eisenbud-Wigner-Smith (EWS) time delay. Considerable additional time shifts caused by the probing infrared field could be identified on the single-particle level. In this contribution we adress the role of electron correlation in the streaking process. We study two-electron systems for which we solve the full time-dependent Schr"odinger equation. For final ionic states with small polarizability correlation effects beyond those of the one-photon transition already included in the EWS time delay are absent. However, for shake-up ionization we find an additional streaking time shift due to the correlated dynamics of the dressed bound electron and the streaked continuum electron.

  1. Deep Vein Thrombosis (DVT)

    MedlinePlus

    ... helps reduce the chances that your blood will pool and clot. You should wear these stockings during ... Make lifestyle changes. Lose weight and quit smoking. Obesity and smoking increase your risk of deep vein ...

  2. What Are Varicose Veins?

    MedlinePlus

    ... family history, older age, gender, pregnancy, overweight or obesity , lack of movement, and leg trauma. Varicose veins are treated with lifestyle changes and medical procedures. The goals of treatment ...

  3. 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.

  4. 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.

  5. Banana streak virus is very diverse in Uganda.

    PubMed

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

    2004-03-01

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

  6. The diversity of Banana streak virus isolates in Uganda.

    PubMed

    Harper, G; Hart, D; Moult, S; Hull, R; Geering, A; Thomas, J

    2005-12-01

    In a study of the variation among isolates of Banana streak virus (BSV) in Uganda, 140 sequences were obtained from 49 samples by PCR across the conserved reverse transcriptase/RNaseH region of the genome. Pairwise comparison of these sequences suggested that they represented 15 different species and phylogenetic analyses showed that all species fell into three major clades based on 28% sequence difference. In addition to the Ugandan sequences, clade I also contained BSV species that are known as both integrated sequences and episomal viruses; clade II also contained integrated BSV sequences but which have not previously been identified as episomal viruses. Clade III comprised of Sugarcane bacilliform virus isolates and Ugandan BSV sequences and for which there is no evidence of integration. The possible reasons for the extraordinary levels of virus sequence variation and the potential origins and epidemiology of these viruses causing banana streak disease are discussed.

  7. Streaked x-ray microscopy of laser-fusion targets

    SciTech Connect

    Price, R.H.; Campbell, E.M.; Rosen, M.D.; Auerbach, J.M.; Phillion, D.W.; Whitlock, R.R.; Obenshain, S.P.; McLean, E.A.; Ripin, B.H.

    1982-08-01

    An ultrafast soft x-ray streak camera has been coupled to a Wolter axisymmetric x-ray microscope. This system was used to observe the dynamics of laser fusion targets both in self emission and backlit by laser produced x-ray sources. Spatial resolution was 7 ..mu..m and temporal resolution was 20 ps. Data is presented showing the ablative acceleration of foils to velocities near 10/sup 7/ cm/sec and the collision of an accelerated foil with a second foil, observed using 3 keV streaked x-ray backlighting. Good agreement was found between hydrocode simulations, simple models of the ablative acceleration and the observed velocities of the carbon foils.

  8. 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

  9. 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.

  10. The development of an improved streak tube for fusion diagnostics

    NASA Astrophysics Data System (ADS)

    Howorth, J. R.; Milnes, J. S.; Fisher, Y.; Jadwin, A.; Boni, R.; Jaanimagi, P. A.

    2016-11-01

    The fusion diagnostic community, including the National Ignition Facility, the Laboratory for Laser Energetics, Megajoule in France, and others require optical recording instruments with precise time resolution covering a dynamic range of many orders of magnitude. In 2012, LLE, Photek, and Sydor Instruments embarked on the re-design of an improved streak tube for fusion diagnostics. As a baseline we started with the Photek ST-Y streak tube which is a member of the RCA design dating back to 1957, because the tube body can accommodate a 35 mm long photocathode, and consequently more fibre coupled diagnostic channels than smaller designs. Electron optical modelling was carried out by both Paul Jaanimagi in the US and by Photek with different software packages in a parallel exercise. Our goal was to address some of the short-comings of this tube, the initial approach being to increase the field between the photocathode and extractor electrode from 700 to 1300 V/mm to reduce space charge effects and to improve time resolution. Many changes and modifications were made: the time resolution was improved to 5 ps, the usable cathode length was increased from 20 mm to 32 mm under high extraction field operation, and the off-axis spatial resolution was substantially improved compared to other tubes of this format. Several tubes have been built and tested in Sydor ROSS-5800 streak cameras.

  11. A new design of filter system in streak camera

    NASA Astrophysics Data System (ADS)

    Zhou, Pengyu; Bai, Yonglin

    2015-10-01

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

  12. 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.

  13. 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.

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

    PubMed

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

    2010-08-01

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

  15. Travelers' Health: Yellow Fever

    MedlinePlus

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

  16. Cell streak imaging cytometry for rare cell detection.

    PubMed

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

    2015-02-15

    Detection of rare cells, such as circulating tumor cells, have many clinical applications. To measure rare cells with increased sensitivity and improved data managements, we developed an imaging flow cytometer with a streak imaging mode capability. The new streak mode imaging mode utilizes low speed video to capture moving fluorescently labeled cells in a flow cell. Each moving cell is imaged on multiple pixels on each frame, where the cell path is marked as a streak line proportional to the length of the exposure. Finding rare cells (e.g., <1 cell/mL) requires measuring larger sample volumes to achieve higher sensitivity, therefore we combined streak mode imaging with a "wide" high throughput flow cell (e.g. flow rates set to 10 mL/min) in contrast to the conventional "narrow" hydrodynamic focusing cells typically used in cytometry that are inherently limited to low flow rates. The new flow cell is capable of analyzing 20 mL/min of fluorescently labeled cells. To further increase sensitivity, the signal to noise ratio of the images was also enhanced by combining three imaging methods: (1) background subtraction, (2) pixel binning, and (3) CMOS color channel selection. The streaking mode cytometer has been used for the analysis of SYTO-9 labeled THP-1 human monocytes in buffer and in blood. Samples of cells at 1 cell/mL and 0.1 cell/mL were analyzed in 30 mL with flow rates set to 10 mL/min and frame rates of 4 fps (frame per second). For the target of 1 cell/mL, an average concentration of 0.91 cell/mL was measured by cytometry, with a standard error of 0.03 (C(95) = 0.85-0.97). For the target of 0.1 cell/mL, an average concentration of 0.083 cell/mL was measured, with a standard error of 0.01 (C(95) = 0.065-0.102). Whole blood was also spiked with SYTO-9 labeled cells to a concentration of 10 cell/mL, and the average flow cytometry measurement was 8.7 cells/mL (i.e. 0.87 cells/mL in diluted blood) with a 95% CL of 8.1-9.2 cells/mL. This demonstrated the ability

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  18. 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.

  19. 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

  20. [Deep vein thrombosis prophylaxis.

    PubMed

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

    2013-01-01

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

  1. 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.

  2. 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.

  3. Transition due to streamwise streaks in a supersonic flat plate boundary layer

    NASA Astrophysics Data System (ADS)

    Paredes, Pedro; Choudhari, Meelan M.; Li, Fei

    2016-12-01

    Transition induced by stationary streaks undergoing transient growth in a supersonic flat plate boundary layer flow is studied using numerical computations. While the possibility of strong transient growth of small-amplitude stationary perturbations in supersonic boundary layer flows has been demonstrated in previous works, its relation to laminar-turbulent transition cannot be established within the framework of linear disturbances. Therefore, this paper investigates the nonlinear evolution of initially linear optimal disturbances that evolve into finite amplitude streaks in the downstream region, and then studies the modal instability of those streaks as a likely cause for the onset of bypass transition. The nonmodal evolution of linearly optimal stationary perturbations in a supersonic, Mach 3 flat plate boundary layer is computed via the nonlinear plane-marching parabolized stability equations (PSE) for stationary perturbations, or equivalently, the perturbation form of parabolized Navier-Stokes equations. To assess the effect of the nonlinear finite-amplitude streaks on transition, the linear form of plane-marching PSE is used to investigate the instability of the boundary layer flow modified by the spanwise periodic streaks. The onset of transition is estimated using an N -factor criterion based on modal amplification of the secondary instabilities of the streaks. In the absence of transient growth disturbances, first mode instabilities in a Mach 3, zero pressure gradient boundary layer reach N =10 at Rex≈107 . However, secondary instability modes of the stationary streaks undergoing transient growth are able to achieve the same N -factor at Rex<2 ×106 when the initial streak amplitude is sufficiently large. In contrast to the streak instabilities in incompressible flows, subharmonic instability modes with twice the fundamental spanwise wavelength of the streaks are found to have higher amplification ratios than the streak instabilities at fundamental

  4. [Puncture of the brachiocephalic vein].

    PubMed

    Schlarb, K

    1986-09-01

    A specific central vein catheter for puncture of the brachiocephalic vein has been developed which is provided with a valve by which air-embolism and unwanted bleeding from the catheter are eliminated. Typical and often serious complications, which can develop on insertion of central vein catheter, can nearly be totally avoided by the puncture technique described.

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

    NASA Astrophysics Data System (ADS)

    Bade, Kyle; Naguib, Ahmed

    2012-11-01

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

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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...

  11. 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.

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

    SciTech Connect

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

    1987-01-30

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

  13. Microprocessor-controlled wide-range streak camera

    NASA Astrophysics Data System (ADS)

    Lewis, Amy E.; Hollabaugh, Craig

    2006-08-01

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

  14. Complete genome sequence and in planta subcellular localization of maize fine streak virus proteins.

    PubMed

    Tsai, Chi-Wei; Redinbaugh, Margaret G; Willie, Kristen J; Reed, Sharon; Goodin, Michael; Hogenhout, Saskia A

    2005-05-01

    The genome of the nucleorhabdovirus maize fine streak virus (MFSV) consists of 13,782 nucleotides of nonsegmented, negative-sense, single-stranded RNA. The antigenomic strand consisted of seven open reading frames (ORFs), and transcripts of all ORFs were detected in infected plants. ORF1, ORF6, and ORF7 had significant similarities to the nucleocapsid protein (N), glycoprotein (G), and polymerase (L) genes of other rhabdoviruses, respectively, whereas the ORF2, ORF3, ORF4, and ORF5 proteins had no significant similarities. The N (ORF1), ORF4, and ORF5 proteins localized to nuclei, consistent with the presence of nuclear localization signals (NLSs) in these proteins. ORF5 likely encodes the matrix protein (M), based on its size, the position of its NLS, and the localization of fluorescent protein fusions to the nucleus. ORF2 probably encodes the phosphoprotein (P) because, like the P protein of Sonchus yellow net virus (SYNV), it was spread throughout the cell when expressed alone but was relocalized to a subnuclear locus when coexpressed with the MFSV N protein. Unexpectedly, coexpression of the MFSV N and P proteins, but not the orthologous proteins of SYNV, resulted in accumulations of both proteins in the nucleolus. The N and P protein relocalization was specific to cognate proteins of each virus. The subcellular localizations of the MFSV ORF3 and ORF4 proteins were distinct from that of the SYNV sc4 protein, suggesting different functions. To our knowledge, this is the first comparative study of the cellular localizations of plant rhabdoviral proteins. This study indicated that plant rhabdoviruses are diverse in genome sequence and viral protein interactions.

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

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

    2016-09-01

    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.

  1. The enigmatic primitive streak: prevailing notions and challenges concerning the body axis of mammals

    PubMed Central

    Downs, Karen M.

    2010-01-01

    The primitive streak establishes the antero-posterior body axis in all amniote species. It is thought to be the conduit through which mesoderm and endoderm progenitors ingress and migrate to their ultimate destinations. Despite its importance, the streak remains poorly defined and one of the most enigmatic structures of the animal kingdom. In particular, the posterior end of the primitive streak has not been satisfactorily identified in any species. Unexpectedly, and contrary to prevailing notions, recent evidence suggests that the murine posterior primitive streak extends beyond the embryo proper. In its extraembryonic site, the streak creates a node-like cell reservoir from which the allantois, a universal caudal appendage of all amniotes and the future umbilical cord of placental mammals, emerges. This new insight into the fetal/umbilical relationship may explain the etiology of a large number of umbilical-associated birth defects, many of which are correlated with abnormalities of the embryonic midline. PMID:19609969

  2. Lipid droplets in atherosclerotic fatty streaks of human aorta

    PubMed Central

    Lang, P. Dieter; Insull, William

    1970-01-01

    Preparations of lipid droplets and droplet-free tissue residue (cytoplasm + membranes + nuclei) were obtained by homogenization and centrifugal separation from intimal fatty streak lesions of aortic atherosclerosis of 21 adults who had died suddenly. Neutral lipids and phospholipids were analyzed by quantitative thin-layer chromatography and cholesteryl ester fatty acids by gas-liquid chromatography. Optical properties of droplets were evaluated by differential counting and sizing procedures with the polarizing microscope. The droplets occurred in mixtures of two forms distinguished by their optical properties, anisotropic (i.e. liquid crystals) and isotropic (true liquids). Both forms had average diameters of about 1.8 μ, with a range of 0.5-5μ. The proportions of the two forms varied with temperature as individual droplets changed their form; anisotropic forms averaged 83.7% at °C and 37.8% at 37°C, with isotropic forms being 16.3 and 62.2% respectively. The proportions of anisotropic forms at 22°C decreased with age. These forms were not separated for chemical analysis. The droplets contained about half the lipid in the lesions. The composition of the lipids of the droplet mixture was remarkably uniform and strikingly different from that of the droplet-free residue, respectively: cholesteryl esters 94.9% vs. 38.7%, free cholesterol 1.7% vs. 18.6%, total phospholipids 1.0% vs. 38.6%, and triglycerides 2.4% vs. 4.0%. The proportions of individual phospholipids, with the exception of lysolecithin, were also different between the preparations. In the droplets only the proportions of lecithin correlated positively with the proportion of anisotropic forms (at 22°C). Droplet cholesteryl esters were particularly rich in oleic acid and when compared to residue esters had more palmitoleic (+0.7%), oleic (+12.3%), and eicosatrienoic (+2.4%) and less palmitic (-2.2%), linoleic (-12.4%), and arachidonic (-1.6%) acids. The proportions of most individual fatty acids of

  3. Genetic variants of Banana streak virus in Mauritius.

    PubMed

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

    2006-01-01

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

  4. Detection of episomal banana streak badnavirus by IC-PCR.

    PubMed

    Harper, G; Dahal, G; Thottappilly, G; Hull, R

    1999-04-01

    A polymerase chain reaction (PCR) based strategy to detect episomal banana streak badnavirus (BSV) in banana and plantain plants that carry integrated BSV sequences was developed. Antisera used in immuno-capture polymerase chain reaction (IC-PCR) are capable of binding a large number of BSV serotypes. The primers used for PCR are capable of annealing to and amplifying across the aspartic protease-reverse transcriptase domain boundaries of both episomal and integrated BSV sequences and result in similar or identical sequence size fragments from either template. However, we show that under the conditions selected for IC-PCR, nuclear, mitochondrial or chloroplast genomic sequences are not amplified and thus only captured episomal BSV is amplified. IC-PCR is suitable for the large-scale screening of Musa for episomal BSV which is necessary for germplasm movement.

  5. Replicative intermediates of maize streak virus found during leaf development.

    PubMed

    Erdmann, Julia B; Shepherd, Dionne N; Martin, Darren P; Varsani, Arvind; Rybicki, Edward P; Jeske, Holger

    2010-04-01

    Geminiviruses of the genera Begomovirus and Curtovirus utilize three replication modes: complementary-strand replication (CSR), rolling-circle replication (RCR) and recombination-dependent replication (RDR). Using two-dimensional gel electrophoresis, we now show for the first time that maize streak virus (MSV), the type member of the most divergent geminivirus genus, Mastrevirus, does the same. Although mastreviruses have fewer regulatory genes than other geminiviruses and uniquely express their replication-associated protein (Rep) from a spliced transcript, the replicative intermediates of CSR, RCR and RDR could be detected unequivocally within infected maize tissues. All replicative intermediates accumulated early and, to varying degrees, were already present in the shoot apex and leaves at different maturation stages. Relative to other replicative intermediates, those associated with RCR increased in prevalence during leaf maturation. Interestingly, in addition to RCR-associated DNA forms seen in other geminiviruses, MSV also apparently uses dimeric open circular DNA as a template for RCR.

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

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

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

  7. 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.

  8. 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.

  9. 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

  10. Field Level RNAi-Mediated Resistance to Cassava Brown Streak Disease across Multiple Cropping Cycles and Diverse East African Agro-Ecological Locations

    PubMed Central

    Wagaba, Henry; Beyene, Getu; Aleu, Jude; Odipio, John; Okao-Okuja, Geoffrey; Chauhan, Raj Deepika; Munga, Theresia; Obiero, Hannington; Halsey, Mark E.; Ilyas, Muhammad; Raymond, Peter; Bua, Anton; Taylor, Nigel J.; Miano, Douglas; Alicai, Titus

    2017-01-01

    Cassava brown streak disease (CBSD) presents a serious threat to cassava production in East and Central Africa. Currently, no cultivars with high levels of resistance to CBSD are available to farmers. Transgenic RNAi technology was employed to combat CBSD by fusing coat protein (CP) sequences from Ugandan cassava brown streak virus (UCBSV) and Cassava brown streak virus (CBSV) to create an inverted repeat construct (p5001) driven by the constitutive Cassava vein mosaic virus promoter. Twenty-five plant lines of cultivar TME 204 expressing varying levels of small interfering RNAs (siRNAs) were established in confined field trials (CFTs) in Uganda and Kenya. Within an initial CFT at Namulonge, Uganda, non-transgenic TME 204 plants developed foliar and storage root CBSD incidences at 96–100% by 12 months after planting. In contrast, 16 of the 25 p5001 transgenic lines showed no foliar symptoms and had less than 8% of their storage roots symptomatic for CBSD. A direct positive correlation was seen between levels of resistance to CBSD and expression of transgenic CP-derived siRNAs. A subsequent CFT was established at Namulonge using stem cuttings from the initial trial. All transgenic lines established remained asymptomatic for CBSD, while 98% of the non-transgenic TME 204 stake-derived plants developed storage roots symptomatic for CBSD. Similarly, very high levels of resistance to CBSD were demonstrated by TME 204 p5001 RNAi lines grown within a CFT over a full cropping cycle at Mtwapa, coastal Kenya. Sequence analysis of CBSD causal viruses present at the trial sites showed that the transgenic lines were exposed to both CBSV and UCBSV, and that the sequenced isolates shared >90% CP identity with transgenic CP sequences expressed by the p5001 inverted repeat expression cassette. These results demonstrate very high levels of field resistance to CBSD conferred by the p5001 RNAi construct at diverse agro-ecological locations, and across the vegetative cropping cycle

  11. Streaking and Wigner time delays in photoemission from atoms and surfaces

    SciTech Connect

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

    2011-09-15

    Streaked photoemission metrology allows the observation of an apparent relative time delay between the detection of photoelectrons from different initial electronic states. This relative delay is obtained by recording the photoelectron yield as a function of the delay between an ionizing ultrashort extended ultraviolet pulse and a streaking infrared (IR) pulse. Theoretically, photoemission delays can be defined based on (i) the phase shift the photoelectron wave function accumulates during the release and propagation of the photoelectron (''Wigner delay'') and, alternatively, (ii) the streaking trace in the calculated photoemission spectrum (''streaking delay''). We investigate the relation between Wigner and streaking delays in the photoemission from atomic and solid-surface targets. For solid targets and assuming a vanishing IR skin depth, both Wigner and streaking delays can be interpreted as an average propagation time needed by photoelectrons to reach the surface, while the two delays differ for nonvanishing skin depths. For atomic targets, the difference between Wigner and streaking delays depends on the range of the ionic potential.

  12. Yellow Fever Vaccine: What You Need to Know

    MedlinePlus

    ... www. immunize. org/ vis 1 What is yellow fever? Yellow fever is a serious disease caused by the ... serious cases) 2 How can I prevent yellow fever? Yellow fever vaccine Yellow fever vaccine can prevent yellow ...

  13. 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.

  14. 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.

  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. 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.

  17. 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.

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

    PubMed Central

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

    2015-01-01

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

  19. 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.

  20. 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.

    2010-10-01

    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.

  1. 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.

  2. Secondary instability analysis of pre-transitional streaks in boundary layers

    NASA Astrophysics Data System (ADS)

    Hack, M. J. Philipp; Zaki, Tamer

    2011-11-01

    In the presence of free-stream vortical disturbances, laminar boundary layers develop streamwise-elongated perturbations of high amplitude, commonly known as Klebanoff streaks. The regions of shear surrounding these primary structures provide the potential for the growth of secondary instabilities which ultimately initiate bypass transition. By means of linear analysis, we examine the secondary instability which precedes the formation of turbulent spots. The base state is extracted from direct numerical simulations of the bypass process. The simulation setup is similar to the work of Jacobs & Durbin (2001), where transition is triggered by broadband free-stream vortical forcing. The velocity field therefore includes a spectrum of streaks with different structures and amplitudes. The stability analysis can nevertheless identify the streaks which indeed develop secondary instabilities and break down to turbulence. The predictions of linear theory, in particular the instability wavelength and phase speed, are compared to the streak instabilities recorded in the DNS of the full bypass process.

  3. 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

  4. Pedestal Craters and Wind Streaks, South Medusae Fossae

    NASA Technical Reports Server (NTRS)

    1999-01-01

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

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

  5. 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.

  6. Genetic Diversity Among Banana streak virus Isolates from Australia.

    PubMed

    Geering, A D; McMichael, L A; Dietzgen, R G; Thomas, J E

    2000-08-01

    ABSTRACT Banana streak virus (BSV) is an important pathogen of bananas and plantains (Musa spp.) throughout the world. We have cloned and sequenced part of the genomes of four isolates of BSV from Australia, designated BSV-RD, BSV-Cav, BSV-Mys, and BSV-GF. These isolates originated from banana cvs. Red Dacca, Williams, Mysore, and Goldfinger, respectively. All clones contained a sequence covering part of open reading frame III and the intergenic region of the badnavirus genome. The sequences were compared with those of other badnaviruses, including BSV-Onne, a previously characterized isolate from Nigeria. The BSV-RD sequence was virtually identical to that of BSV-Onne, differing by only two nucleotides over 1,292 bp. However, BSV-Cav, -Mys, and -GF were divergent in nucleotide sequence. Phylogenetic analyses using conserved sequences in the ribonuclease H domain revealed that all BSV isolates were more closely related to each other than to any other badnavirus. BSV-Cav was most closely related to BSV-Onne, and there was 95.1% identity between the two amino acid sequences. Other relationships between the BSV isolates were less similar, with sequence identities ranging from 66.4 to 78.2%, which is a magnitude comparable to the distance between some of the recognized badnavirus species. Immunocapture-polymerase chain reaction assays have been developed, allowing specific detection and differentiation of the four isolates of BSV.

  7. 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.

  8. 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

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

    PubMed

    Yamaue, Yasuhiro; Hosaka, Yoshinao Z; Uehara, Masato

    2015-02-01

    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/mm(2). 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.

  10. 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.

  11. 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.

  12. 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.

  13. Varicose Veins and Venous Insufficiency

    MedlinePlus

    ... that impact a person’s quality of life. Endovenous laser ablation treatment (EVLT) EVLT is a minimally invasive ... ray images ), the interventional radiologist threads a thin laser fiber into the problem vein through a tiny ...

  14. How Are Varicose Veins Treated?

    MedlinePlus

    ... and scarring. Sclerotherapy Sclerotherapy (SKLER-o-ther-ah-pe) uses a liquid chemical to close off a ... Microsclerotherapy Microsclerotherapy (MI-kro-SKLER-o-ther-ah-pe) is used to treat spider veins and other ...

  15. What Is Deep Vein Thrombosis?

    MedlinePlus

    ... deep vein of the leg can break off, travel to the lungs, and block blood flow. Rate This Content: NEXT >> Updated: October 28, 2011 Twitter Facebook YouTube Google+ SITE INDEX ACCESSIBILITY PRIVACY STATEMENT FOIA NO FEAR ACT ...

  16. [Surgery of essential varicose veins].

    PubMed

    Maraval, M

    1994-03-15

    Idiopathic varicose veins of the lower limbs are a frequent but benign disorder. Surgery is only a moment in the course of the disease. Although not the only treatment of essential varicose veins, surgery by an experienced team performing crossectomy, stripping by intussusception using a stripper, and phlebectomy gives fully satisfactory results, both to patient and to physician, in over 80% of cases. New techniques were recently developed that, at present, have not confirmed early hopes.

  17. Streak Imaging Flow Cytometer for Rare Cell Analysis.

    PubMed

    Balsam, Joshua; Bruck, Hugh Alan; Ossandon, Miguel; Prickril, Ben; Rasooly, Avraham

    2017-01-01

    There is a need for simple and affordable techniques for cytology for clinical applications, especially for point-of-care (POC) medical diagnostics in resource-poor settings. However, this often requires adapting expensive and complex laboratory-based techniques that often require significant power and are too massive to transport easily. One such technique is flow cytometry, which has great potential for modification due to the simplicity of the principle of optical tracking of cells. However, it is limited in that regard due to the flow focusing technique used to isolate cells for optical detection. This technique inherently reduces the flow rate and is therefore unsuitable for rapid detection of rare cells which require large volume for analysis.To address these limitations, we developed a low-cost, mobile flow cytometer based on streak imaging. In our new configuration we utilize a simple webcam for optical detection over a large area associated with a wide-field flow cell. The new flow cell is capable of larger volume and higher throughput fluorescence detection of rare cells than the flow cells with hydrodynamic focusing used in conventional flow cytometry. The webcam is an inexpensive, commercially available system, and for fluorescence analysis we use a 1 W 450 nm blue laser to excite Syto-9 stained cells with emission at 535 nm. We were able to detect low concentrations of stained cells at high flow rates of 10 mL/min, which is suitable for rapidly analyzing larger specimen volumes to detect rare cells at appropriate concentration levels. The new rapid detection capabilities, combined with the simplicity and low cost of this device, suggest a potential for clinical POC flow cytometry in resource-poor settings associated with global health.

  18. The evolution of amniote gastrulation: the blastopore-primitive streak transition.

    PubMed

    Stower, Matthew J; Bertocchini, Federica

    2017-03-01

    In the animal kingdom, gastrulation, the process by which the primary germ layers are formed involves a dramatic transformation in the topology of the cells that give rise to all of the tissues of the adult. Initially formed as a mono-layer, this tissue, the epiblast, becomes subdivided through the internalization of cells, thereby forming a two (bi-laminar) or three (tri-laminar) layered embryo. This morphogenetic process coordinates the development of the fundamental body plan and the three-body axes (antero-posterior, dorso-ventral, and left-right) and begins a fundamental segregation of cells toward divergent developmental fates. In humans and other mammals, as well as in avians, gastrulating cells internalize along a structure, called the primitive streak, which builds from the periphery toward the center of the embryo. How these morphogenetic movements are orchestrated and evolved has been a question for developmental biologists for many years. Is the primitive streak a feature shared by the whole amniote clade? Insights from reptiles suggest that the primitive streak arose independently in mammals and avians, while the reptilian internalization site is a structure half-way between an amphibian blastopore and a primitive streak. The molecular machinery driving primitive streak formation has been partially dissected using mainly the avian embryo, revealing a paramount role of the planar cell polarity (PCP) pathway in streak formation. How did the employment of this machinery evolve? The reptilian branch of the amniote clade might provide us with useful tools to investigate the evolution of the amniote internalization site up to the formation of the primitive streak. WIREs Dev Biol 2017, 6:e262. doi: 10.1002/wdev.262 For further resources related to this article, please visit the WIREs website.

  19. 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.

  20. Identification and molecular characterization of a novel sugarcane streak mastrevirus and an isolate of the A-strain of maize streak virus from sugarcane in Nigeria.

    PubMed

    Yahaya, Adama; Dangora, Danladi B; Alegbejo, Matthew D; Kumar, P Lava; Alabi, Olufemi J

    2017-02-01

    Sugarcane and maize plants showing symptoms typical of those described for the so-called "African streak viruses" (AfSVs) were encountered during field surveys conducted from February to July 2015 to document viruses infecting both crops across the northern Guinea savannah region of Nigeria. As part of this study, two categories of complete mastrevirus-like genome sequences were obtained from nine samples (maize = 2; sugarcane = 7). In pairwise comparisons, the full-length genomes of the first sequence category (2,687 nt each; maize = 2; sugarcane = 2) shared 96 to 99% identity with global isolates of the A-strain of maize streak virus (MSV-A), indicating that sugarcane may also serve as a reservoir host to MSV-A. Analysis of the complete genomes belonging to the second sequence category (2,757 nt each; sugarcane = 5) showed that they shared 42 to 67% identity with their closest AfSV relatives, thus indicating that they represent sequences of a novel mastrevirus. Both sequence categories shared 61-62% sequence identity with each other. Further analysis revealed that the novel sugarcane-infecting virus, tentatively named as sugarcane chlorotic streak virus (SCSV), arose from a putative interspecific recombination event involving two grass-infecting mastreviruses, eragrostis streak virus and urochloa streak virus, as putative parental sequences. The results of this study add to the repertoire of diverse AfSVs present in cereal and sugarcane mixed cropping landscapes in the northern Guinea savannah region of Nigeria, with implications for disease epidemiology.

  1. 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

  2. Gypsum veins in Triassic Moenkopi mudrocks of southern Utah: Analogs to calcium sulfate veins on Mars

    NASA Astrophysics Data System (ADS)

    Young, B. W.; Chan, M. A.

    2017-01-01

    Well-exposed gypsum veins in the Triassic Moenkopi formation in southern Utah, USA, are similar to veins at Endeavour and Gale Craters on Mars. Both Moenkopi and Mars veins are hydrated calcium sulfate, have fibrous textures, and crosscut other diagenetic features. Moenkopi veins are stratigraphically localized with strontium and sulfur isotope ratios similar to primary Moenkopi sulfate beds and are thus interpreted to be sourced from within the unit. Endeavour veins seem to be distributed by lithology and may have a local source. Gale veins cut across multiple lithologies and appear to be sourced from another stratigraphic interval. Evaluation of vein network geometries indicates that horizontal Moenkopi veins are longer and thicker than vertical veins. Moenkopi veins are also generally oriented with the modern stress field, so are interpreted to have formed in the latest stages of exhumation. Endeavour veins appear to be generally vertical and oriented parallel to the margins of Cape York and are interpreted to have formed in response to topographic collapse of the crater rim. Gale horizontal veins appear to be slightly more continuous than vertical veins and may have formed during exhumation. Abrupt changes in orientation, complex crosscutting relationships, and fibrous (antitaxial) texture in Moenkopi and Mars veins suggest emplacement via hydraulic fracture at low temperatures. Moenkopi and Mars veins are interpreted as late-stage diagenetic features that have experienced little alteration since emplacement. Moenkopi veins are useful terrestrial analogs for Mars veins because vein geometry, texture, and chemistry record information about crustal deformation and vein emplacement.

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

    NASA Astrophysics Data System (ADS)

    Settles, Gary

    2013-11-01

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

  4. Distinct Wnt-driven primitive streak-like populations reflect in vivo lineage precursors

    PubMed Central

    Tsakiridis, Anestis; Huang, Yali; Blin, Guillaume; Skylaki, Stavroula; Wymeersch, Filip; Osorno, Rodrigo; Economou, Costas; Karagianni, Eleni; Zhao, Suling; Lowell, Sally; Wilson, Valerie

    2014-01-01

    During gastrulation, epiblast cells are pluripotent and their fate is thought to be constrained principally by their position. Cell fate is progressively restricted by localised signalling cues from areas including the primitive streak. However, it is unknown whether this restriction accompanies, at the individual cell level, a reduction in potency. Investigation of these early transition events in vitro is possible via the use of epiblast stem cells (EpiSCs), self-renewing pluripotent cell lines equivalent to the postimplantation epiblast. Strikingly, mouse EpiSCs express gastrulation stage regional markers in self-renewing conditions. Here, we examined the differentiation potential of cells expressing such lineage markers. We show that undifferentiated EpiSC cultures contain a major subfraction of cells with reversible early primitive streak characteristics, which is mutually exclusive to a neural-like fraction. Using in vitro differentiation assays and embryo grafting we demonstrate that primitive streak-like EpiSCs are biased towards mesoderm and endoderm fates while retaining pluripotency. The acquisition of primitive streak characteristics by self-renewing EpiSCs is mediated by endogenous Wnt signalling. Elevation of Wnt activity promotes restriction towards primitive streak-associated lineages with mesendodermal and neuromesodermal characteristics. Collectively, our data suggest that EpiSC pluripotency encompasses a range of reversible lineage-biased states reflecting the birth of pioneer lineage precursors from a pool of uncommitted EpiSCs similar to the earliest cell fate restriction events taking place in the gastrula stage epiblast. PMID:24595287

  5. 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

  6. Minimally invasive treatments for perforator vein insufficiency

    PubMed Central

    Salazar, Gloria Maria; Prabhakar, Anand M.; Ganguli, Suvranu

    2016-01-01

    Incompetent superficial veins are the most common cause of lower extremity superficial venous reflux and varicose veins; however, incompetent or insufficient perforator veins are the most common cause of recurrent varicose veins after treatment, often unrecognized. Perforator vein insufficiency can result in pain, skin changes, and skin ulcers, and often merit intervention. Minimally invasive treatments have replaced traditional surgical treatments for incompetent perforator veins. Current minimally invasive treatment options include ultrasound guided sclerotherapy (USGS) and endovascular thermal ablation (EVTA) with either laser or radiofrequency energy sources. Advantages and disadvantages of each modality and knowledge on these treatments are required to adequately address perforator venous disease. PMID:28123979

  7. Molecular genetic analysis and evolution of begomoviruses and betasatellites causing yellow mosaic disease of bhendi.

    PubMed

    Kumar, R Vinoth; Prasanna, H C; Singh, A K; Ragunathan, D; Garg, G K; Chakraborty, S

    2017-04-01

    In India, Bhendi yellow vein mosaic disease (BYVMD) is one of the most economically important diseases of bhendi/okra and is caused by a complex of monopartite begomovirus (Bhendi yellow vein mosaic virus-BYVMV) and betasatellite (Bhendi yellow vein betasatellite-BYVB). In this study, we have analyzed the role of possible evolutionary factors involved in the evolution of BYVMV and BYVB isolates. Evidence of inter-species and inter-strain recombination events was detected among the viral isolates, and majority of these recombinant isolates possess microsatellites in their genome. Recombination analysis suggests that cotton-infecting and bhendi-infecting begomoviruses probably share a recent common ancestor. In addition to genetic differentiation and gene flow, high degree of genetic variability was detected among the viral population. A strong purifying selection seems to be acting on the viral coding regions. The nucleotide substitution rate of V1 gene (for BYVMV) and βC1 gene (for BYVB) was estimated to be 7.55 × 10(-4) and 2.25 × 10(-3) nucleotide substitutions/site/year, respectively. The present study underlines that the evolution of BYVMD-associated viral components is driven by selection acting on the genetic variation generated by recombination and mutation.

  8. Leiomyosarcoma of the splenic vein.

    PubMed

    Aguilar, Cristian; Socola, Francisco; Donet, Jean A; Gallastegui, Nicolas; Hernandez, Gabriel A

    2013-01-01

    Leiomyosarcomas arising from the wall of blood vessels are rare and aggressive neoplasm. We report a case of a previously healthy 66-year-old woman who presented with intermittent abdominal pain, progressive constipation, and weight loss. Abdominal computed tomography showed a 12 cm solid heterogeneous tumor in the tail of the pancreas. The patient subsequently underwent surgical resection of the pancreatic mass. Surprisingly, histological and immunohistochemical analyses revealed leiomyosarcoma arising from the smooth muscle of the splenic vein. After surgery, she received adjuvant chemotherapy. One year later, there was no evidence of local recurrence. In this paper, we discuss the available information about leiomyosarcomas of splenic vein and its management.

  9. Extrahepatic Portal Vein Obstruction and Portal Vein Thrombosis in Special Situations: Need for a New Classification

    PubMed Central

    Wani, Zeeshan A.; Bhat, Riyaz A.; Bhadoria, Ajeet S.; Maiwall, Rakhi

    2015-01-01

    Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized. PMID:26021771

  10. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

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

  12. Variable features on Mars V - Evidence for crater streaks produced by wind erosion

    NASA Technical Reports Server (NTRS)

    Veverka, J.

    1975-01-01

    High-resolution television pictures obtained by Mariner 9 are presented as evidence to show that the ragged dark streaks which appeared behind many dark craters several months after the end of the 1971 global dust storm resulted from wind erosion of a thin surface veneer consisting of dust-storm fallout. The pictures were taken over an area near the border between Mare Serpentis and Pandorae Fretum (approximately 30 deg S, 335 deg W). The high-resolution pictures are compared with low-resolution views of the same area, and it is shown that one very long dark streak is interrupted by a rille. It is concluded that this interruption proves that the dark streaks were produced by the present erosional mechanism.

  13. 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.

  14. Angiosarcoma of common iliac vein

    PubMed Central

    Ibis, Kamuran; Usta, Ufuk; Cosar, Rusen; Ibis, Cem

    2015-01-01

    Angiosarcoma is a rare malignant tumour of endothelial cells. Primary angiosarcoma of venous origin is extremely rare, and has a very poor prognosis. A 63-year-old woman with retroperitoneal mass underwent en bloc resection on a part of iliac vein followed by adjuvant radiotherapy. No recurrence was detected during 3 years of follow-up. PMID:25596292

  15. Phylogenetic and recombination analysis of rice black-streaked dwarf virus segment 9 in China.

    PubMed

    Zhou, Yu; Weng, Jian-Feng; Chen, Yan-Ping; Liu, Chang-Lin; Han, Xiao-Hua; Hao, Zhuan-Fang; Li, Ming-Shun; Yong, Hong-Jun; Zhang, De-Gui; Zhang, Shi-Huang; Li, Xin-Hai

    2015-04-01

    Rice black-streaked dwarf virus (RBSDV) is an economically important virus that causes maize rough dwarf disease and rice black-streaked dwarf disease in East Asia. To study RBSDV variation and recombination, we examined the segment 9 (S9) sequences of 49 RBSDV isolates from maize and rice in China. Three S9 recombinants were detected in Baoding, Jinan, and Jining, China. Phylogenetic analysis showed that Chinese RBSDV isolates could be classified into two groups based on their S9 sequences, regardless of host or geographical origin. Further analysis suggested that S9 has undergone negative and purifying selection.

  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. Self-sustaining process through streak generation in a flat-plate boundary layer.

    PubMed

    Duriez, Thomas; Aider, Jean-Luc; Wesfreid, José Eduardo

    2009-10-02

    The existence of a self-sustaining process between streamwise vortices and streaks has been suggested at moderate Reynolds numbers. Such a mechanism has never been demonstrated experimentally. Using small cylinders as vortex generators to create streamwise counterrotating vortices, we show, through the characterization of the spatial transient growth of the energy of the longitudinal and spanwise velocity perturbations, that such a mechanism exists above a given Reynolds number. From instantaneous particle image velocimetry fields in a horizontal plane, we show that the self-sustaining process can also be associated with the longitudinal destabilization of streamwise streaks.

  18. 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

  19. How Is Deep Vein Thrombosis Diagnosed?

    MedlinePlus

    ... Vein Thrombosis Diagnosed? Your doctor will diagnose deep vein thrombosis (DVT) based on your medical history, a physical exam, and test results. He or she will identify your risk factors and rule out other causes of your symptoms. ...

  20. What Are Varicose Veins? (For Kids)

    MedlinePlus

    ... Dictionary of Medical Words En Español What Other Kids Are Reading Taking Care of Your Ears Taking ... X-ray What Are Varicose Veins? KidsHealth > For Kids > What Are Varicose Veins? Print A A A ...

  1. 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.

  2. Common femoral vein reconstruction using internal jugular vein after blast injury.

    PubMed

    Holt, Andrew M; West, Charles A; Davis, James A; Gilani, Ramyar; Askenasy, Eric

    2014-10-01

    Common femoral vein traumatic injuries are rare. Surgical management is controversial and by nature case specific. In this report, we present an unusual case of an isolated common femoral vein injury from a gunshot blast repaired with an interposition internal jugular vein bypass. To our knowledge, this is the first reported case of an isolated common femoral vein reconstructed in this manner.

  3. 17DD yellow fever vaccine

    PubMed Central

    Martins, Reinaldo M.; Maia, Maria de Lourdes S.; Farias, Roberto Henrique G.; Camacho, Luiz Antonio B.; Freire, Marcos S.; Galler, Ricardo; Yamamura, Anna Maya Yoshida; Almeida, Luiz Fernando C.; Lima, Sheila Maria B.; Nogueira, Rita Maria R.; Sá, Gloria Regina S.; Hokama, Darcy A.; de Carvalho, Ricardo; Freire, Ricardo Aguiar V.; Filho, Edson Pereira; Leal, Maria da Luz Fernandes; Homma, Akira

    2013-01-01

    Objective: To verify if the Bio-Manguinhos 17DD yellow fever vaccine (17DD-YFV) used in lower doses is as immunogenic and safe as the current formulation. Results: Doses from 27,476 IU to 587 IU induced similar seroconversion rates and neutralizing antibodies geometric mean titers (GMTs). Immunity of those who seroconverted to YF was maintained for 10 mo. Reactogenicity was low for all groups. Methods: Young and healthy adult males (n = 900) were recruited and randomized into 6 groups, to receive de-escalating doses of 17DD-YFV, from 27,476 IU to 31 IU. Blood samples were collected before vaccination (for neutralization tests to yellow fever, serology for dengue and clinical chemistry), 3 to 7 d after vaccination (for viremia and clinical chemistry) and 30 d after vaccination (for new yellow fever serology and clinical chemistry). Adverse events diaries were filled out by volunteers during 10 d after vaccination. Volunteers were retested for yellow fever and dengue antibodies 10 mo later. Seropositivity for dengue was found in 87.6% of volunteers before vaccination, but this had no significant influence on conclusions. Conclusion: In young healthy adults Bio-Manguinhos/Fiocruz yellow fever vaccine can be used in much lower doses than usual. International Register ISRCTN 38082350. PMID:23364472

  4. 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.

  5. Varicose veins; a practical approach to treatment.

    PubMed

    ELLENBURG, R

    1958-05-01

    Adequate treatment of varicose veins requires thorough mapping of perforating veins, communicating veins and "blow out" areas. Combined ligations, stripping and injection of sclerotic substances after operation is the most effective regimen of therapy. The technique of stripping is facilitated by isolating the saphenous vein at the ankle, inserting the stripper from below upward, then making a transverse groin incision over the palpable stripper. The tip of the stripper should be twice the diameter of the vein to be removed. Stripping should be done with the patient in the Trendelenburg position. All patients must be examined at regular intervals after operation and injection of sclerosing material carried out as necessary.

  6. Preduodenal portal vein: surgery and radiographic appearance.

    PubMed

    Fernandes, E T; Burton, E M; Hixson, S D; Hollabaugh, R S

    1990-12-01

    Preduodenal portal vein is rare, with 63 cases reported in the literature. In general, this anomaly occurs in children with associated small bowel obstruction. We report a newborn infant who presented with duodenal stenosis, mongolism, and preduodenal portal vein. Treatment consisted of a duodenoduodenal anastomosis without mobilizing the portal vein. The correlation between imaging techniques and the operative findings is discussed. Because identification of preduodenal portal vein at surgery is important, preoperative sonography may be useful in selected cases to define the position of the vein.

  7. Streak camera measurements of laser pulse temporal dispersion in short graded-index optical fibers

    SciTech Connect

    Lerche, R.A.; Phillips, G.E.

    1981-08-28

    Streak camera measurements were used to determine temporal dispersion in short (5 to 30 meter) graded-index optical fibers. Results show that 50-ps, 1.06-..mu..m and 0.53-..mu..m laser pulses can be propagated without significant dispersion when care is taken to prevent propagation of energy in fiber cladding modes.

  8. A time-dependent vector field topology based on streak surfaces.

    PubMed

    Uffinger, Markus; Sadlo, Filip; Ertl, Thomas

    2013-03-01

    It was shown recently how the 2D vector field topology concept, directly applicable to stationary vector fields only, can be generalized to time-dependent vector fields by replacing the role of stream lines by streak lines. The present paper extends this concept to 3D vector fields. In traditional 3D vector field topology separatrices can be obtained by integrating stream lines from 0D seeds corresponding to critical points. We show that in our new concept, in contrast, 1D seeding constructs are required for computing streak-based separatrices. In analogy to the 2D generalization we show that invariant manifolds can be obtained by seeding streak surfaces along distinguished path surfaces emanating from intersection curves between codimension-1 ridges in the forward and reverse finite-time Lyapunov exponent (FTLE) fields. These path surfaces represent a time-dependent generalization of critical points and convey further structure in time-dependent topology of vector fields. Compared to the traditional approach based on FTLE ridges, the resulting streak manifolds ease the analysis of Lagrangian coherent structures (LCS) with respect to visual quality and computational cost, especially when time series of LCS are computed. We exemplify validity and utility of the new approach using both synthetic examples and computational fluid dynamics results.

  9. 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...

  10. Two-color spatial and temporal temperature measurements using a streaked soft x-ray imager

    NASA Astrophysics Data System (ADS)

    Moore, A. S.; Benstead, J.; Ahmed, M. F.; Morton, J.; Guymer, T. M.; Soufli, R.; Pardini, T.; Hibbard, R. L.; Bailey, C. G.; Bell, P. M.; Hau-Riege, S.; Bedzyk, M.; Shoup, M. J.; Regan, S. P.; Agliata, T.; Jungquist, R.; Schmidt, D. W.; Kot, L. B.; Garbett, W. J.; Rubery, M. S.; Skidmore, J. W.; Gullikson, E.; Salmassi, F.

    2016-11-01

    A dual-channel streaked soft x-ray imager has been designed and used on high energy-density physics experiments at the National Ignition Facility. This streaked imager creates two images of the same x-ray source using two slit apertures and a single shallow angle reflection from a nickel mirror. Thin filters are used to create narrow band pass images at 510 eV and 360 eV. When measuring a Planckian spectrum, the brightness ratio of the two images can be translated into a color-temperature, provided that the spectral sensitivity of the two images is well known. To reduce uncertainty and remove spectral features in the streak camera photocathode from this photon energy range, a thin 100 nm CsI on 50 nm Al streak camera photocathode was implemented. Provided that the spectral shape is well-known, then uncertainties on the spectral sensitivity limits the accuracy of the temperature measurement to approximately 4.5% at 100 eV.

  11. 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...

  12. Stable Resistance to Wheat streak mosaic virus in wheat mediated by RNAi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is one of the major wheat viruses in the Great Plains of the United States. Cultural practices are the primary method of disease management, though not fully effective. Genetic resistance is available but is temperature sensitive. Alternative approaches to viral res...

  13. Resistance to Wheat streak mosaic virus identified in synthetic wheat lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is a significant pathogen in wheat that causes economic loss each year. WSMV is typically controlled using cultural practices such as the removal of volunteer wheat. Genetic resistance is limited. Until recently, no varieties have been available with major resista...

  14. 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...

  15. 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...

  16. Simultaneous velocity interferometry and electronic streak photography of laser-launched plates

    SciTech Connect

    Paisley, D.L.; Stahl, D.B.; Garcia, I.A.

    1991-01-01

    Laser-launched, miniature, pseudo-one-dimensional flyer plates are evaluated by three distinct optical techniques that may be incorporated into an optical diagnostic system to give a complete understanding of the plate performance. These techniques are: velocity interferometry, streak photography, and pulsed laser stereo photography. 2 refs., 5 figs.

  17. 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...

  18. 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...

  19. Jet streak modification via diabatic heating during periods of intense cool-season precipitation

    NASA Astrophysics Data System (ADS)

    Market, Patrick Shawn

    The propagation of a jet streak in the presence of predominately stable latent heat release is examined. Unlike many prior studies which emphasized latent heat release due to mesoscale convective system activity this work addresses cool season mid-latitude weather systems in which stable latent heat release played a significant role. In both cool and warm seasons, the result is the same: the amplification of a pre-existing jet streak, or the in situ development of a new jet streak. The former situation is more typical of the cool season when thermal gradients and the jet stream are both stronger and more conducive to the transient baroclinic waves which engender streaks in the jet stream flow, while the latter development tends to be the product of a warm season environment when the background thermal and flow patterns are weaker. In this work, the development of a pre-existing straight- line jet streak upstream of its prior location (``backbuilding'') presumably due to latent heat release is studied. Both dry and moist adiabatic simulations with a mesoscale numerical model indicate that backbuilding occurs in the absence of latent heat release (dry run) due to confluence but is enhanced when such heating is included (moist run). This is due to the latent heat release and consequent warming of the column in which it occurs, thus altering the height gradient. Such a process causes accelerations in the flow. Moreover, the mid-tropospheric nature of the stable latent heating causes the backbuilding to be maximized in the mid-troposphere (500 to 400 hPa). Isentropic coordinate analyses of the model output are employed in the estimation of latent heating and ageostrophic wind components. In terms of sensible weather, the propagating jet streak tends to initiate precipitation in its right entrance region because of the induced ascent. In the present case, the latent heat release associated with this precipitation acted to anchor the jet streak in place and even build

  20. 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.

  1. Management of varicose veins and venous insufficiency.

    PubMed

    Hamdan, Allen

    2012-12-26

    Chronic venous disease, reviewed herein, is manifested by a spectrum of signs and symptoms, including cosmetic spider veins, asymptomatic varicosities, large painful varicose veins, edema, hyperpigmentation and lipodermatosclerosis of skin, and ulceration. However, there is no definitive stepwise progression from spider veins to ulcers and, in fact, severe skin complications of varicose veins, even when extensive, are not guaranteed. Treatment options range from conservative (eg, medications, compression stockings, lifestyle changes) to minimally invasive (eg, sclerotherapy or endoluminal ablation), invasive (surgical techniques), and hybrid (combination of ≥1 therapies). Ms L, a 68-year-old woman with varicose veins, is presented. She has had vein problems over the course of her life. Her varicose veins recurred after initial treatment, and she is now seeking guidance regarding her current treatment options.

  2. Laboratory Simulations and Spectral Analyses of Recurring Slope Streaks on Mars

    NASA Astrophysics Data System (ADS)

    Wing, B.; Irvin, B.; Hibbitts, C.; Mushkin, A.

    2014-12-01

    Low albedo streaks on Martian slopes have been cited as possible evidence for present-day intermittent and repeated surface flow of water, or brine (Mushkin et al., 2010). Also termed as Recurring Slope Lineae (1), such streaks can grow, fade, and recur repeatedly on the same slopes. Although distinguishable by being darker than surrounding terrain slope streaks have no diagnostic spectral absorption features (2). A leading hypothesis is formation by multiple wetting and drying events. Laboratory investigations have previously explored this possibility (e.g 3). When wetted with brines, soils darken, but as the sample dries, it brightens again. Wetting also results in absorption bands near 1.5 and 2 microns, which are not detected in spectra of slope streaks. Additionally, dried brines of most salts such as MgSO4, or other sulfates and many chlorides are brighter than Martian soils. However, iron chlorides are a salt that have lower albedo than most other salts and may present a mechanism for darkening slope streaks without inducing a spectral absorption feature. To explore this hypothesis, we have begun to conduct experiments investigating the spectra of iron chloride chloride solutions wetting palagonite and subsequently drying under Martian atmospheric conditions. Preliminary experiments demonstrate that FeIII chloride dried onto palagonite has no absorption features in the NIR and SWIR and remains dark and red. However, these chlorides will oxidize under terrestrial conditions forming Fe2O3 as they dry. We have constructed an environmental chamber that mimics Martian oxygen fugacity though a combination of vacuum and N2 purging, allowing for sample wetting and drying while concurrently taking spectra from 0.4 to 2.4 microns. Results from this experimental setup under Martian atmospheric conditions will be presented. References: (1) McEwen et al., (2011) Science, 333, 740-743, (2) Mushkin et al., (2010) Geophys. Res. Lett., 37, L22201, doi: 10.1029/2010GL044535

  3. Mortality after portal vein embolization

    PubMed Central

    Lee, Eung Chang; Park, Sang-Jae; Han, Sung-Sik; Park, Hyeong Min; Lee, Seung Duk; Kim, Seong Hoon; Lee, In Joon; Kim, Hyun Beom

    2017-01-01

    Abstract Portal vein embolization (PVE) is increasingly performed worldwide to reduce the possibility of liver failure after extended hepatectomy, by inducing future liver remnant (FLR) hypertrophy and atrophy of the liver planned for resection. The procedure is known to be very safe and to have few procedure-related complications. In this study, we described 2 elderly patients with Bismuth–Corlette type IV Klatskin tumor who underwent right trisectional PVE involving the embolization of the right portal vein, the left medial sectional portal branch, and caudate portal vein. Within 1 week after PVE, patients went into sepsis combined with bile leak and died within 1 month. Sepsis can cause acute liver failure in patients with chronic liver disease. In this study, the common patient characteristics other than sepsis, that is, trisectional PVE; chronic alcoholism; aged >65 years; heart-related comorbidity; and elevated serum total bilirubin (TB) level (7.0 mg/dL) at the time of the PVE procedure in 1 patient, and concurrent biliary procedure, that is, percutaneous transhepatic biliary drainage in the other patient might have affected the outcomes of PVE. These cases highlight that PVE is not a safe procedure. Care should be taken to minimize the occurrence of infectious events because sepsis following PVE can cause acute liver failure. Additionally, prior to performing PVE, the extent of PVE, chronic alcohol consumption, age, comorbidity, long-lasting jaundice, concurrent biliary procedure, etc. should be considered for patient safety. PMID:28178122

  4. Interaction of tomato yellow leaf curl virus with diverse betasatellites enhances symptom severity.

    PubMed

    Ito, Takuya; Kimbara, Junji; Sharma, Pradeep; Ikegami, Masato

    2009-01-01

    The complete nucleotide sequence was determined for a begomovirus isolated from tomato exhibiting leaf curling and yellowing symptoms in Tochigi Prefecture in Japan. The genome organization of this virus was similar to those of other Old World monopartite begomoviruses. Neither a DNA betasatellite nor a DNA-B component was detected. It had the highest total nucleotide sequence identity (99%) with tomato yellow leaf curl virus-Israel[Japan:Tosa:2005] (TYLCV-IL[JR:Tos:05]) and TYLCV-Israel[Japan:Haruno:2005] (TYLCV-IL[JR:Han:05]). Its coat protein V1 also showed an identical amino acid sequence with those of TYLCV-IL[JR:Tos:05] and TYLCV-IL[JR:Han:05]. Thus, the begomovirus was determined to be an isolate of TYLCV-IL designated as TYLCV-Israel[Japan:Tochigi:2007] (TYLCV-IL[JR:Toc:07]). We investigated the interaction of TYLCV-IL[JR:Toc:07] with two known satellites associated with tomato yellow dwarf disease in Japan, tobacco leaf curl Japan betasatellite [Japan:Ibaraki:2006] and honeysuckle yellow vein mosaic betasatellite [Japan:Nara:2006], as well as with tomato leaf curl Philippines betasatellite [Philippines:Laguna1:2008], in tomato and Nicotiana benthamiana plants. TYLCV-IL[JR:Toc:07] trans-replicated these betasatellites, inducing more severe tomato yellow leaf curl disease-related symptoms than TYLCV-IL[JR:Toc:07] alone.

  5. Veins of the thoracic limb of the Van cat.

    PubMed

    Ozüdoğru, Z; Aksoy, G; Soygüder, Z; Ozmen, E

    2003-04-01

    The drainage of the thoracic limb of the Van cat was performed by the superficial and deep vein systems. The superficial system was constituted by the cephalic vein and its branches. The deep vein system was constituted by the axillary vein and its branches. The two vein systems anastomosed with each other at various points along their courses. The cephalic vein emerged from the external jugular vein together with the superficial cervical vein. The axillary vein continued the subclavian vein. It ran caudoventrally and gave off the subscapular vein, at the level of the shoulder joint, then gave off two independent branches, which were the external thoracic veins. Then the rest of the vessel continued as the brachial vein. The thoracodorsal vein was formed by the communicate ramus vein which arose between the subscapular vein and the brachial vein. The cranial circumflex humeral vein arose double from the subscapular vein. One of them anastomosed with the deep brachial vein and the other one drained the biceps and the deep pectoral muscles. The cranial interosseous vein from the caudal aspects of the brachial vein and passed the interosseous space of the antebrachium then ran to the lateral aspect of the forearm. The caudal interosseous vein arose from the ulnar vein (in two specimens) and the median vein together with the ulnar vein (in two specimens) or independently from the median vein (in one specimen). Although many similarities were found in the veins of the thoracic limb of the Van cat as compared with the domestic cat, some significant differences were noted in the origin, course, anastomosing and ramification of veins of the thoracic limb.

  6. Improving the off-axis spatial resolution and dynamic range of the NIF X-ray streak cameras (invited)

    NASA Astrophysics Data System (ADS)

    MacPhee, A. G.; Dymoke-Bradshaw, A. K. L.; Hares, J. D.; Hassett, J.; Hatch, B. W.; Meadowcroft, A. L.; Bell, P. M.; Bradley, D. K.; Datte, P. S.; Landen, O. L.; Palmer, N. E.; Piston, K. W.; Rekow, V. V.; Hilsabeck, T. J.; Kilkenny, J. D.

    2016-11-01

    We report simulations and experiments that demonstrate an increase in spatial resolution of the NIF core diagnostic x-ray streak cameras by at least a factor of two, especially off axis. A design was achieved by using a corrector electron optic to flatten the field curvature at the detector plane and corroborated by measurement. In addition, particle in cell simulations were performed to identify the regions in the streak camera that contribute the most to space charge blurring. These simulations provide a tool for convolving synthetic pre-shot spectra with the instrument function so signal levels can be set to maximize dynamic range for the relevant part of the streak record.

  7. Improving the off-axis spatial resolution and dynamic range of the NIF X-ray streak cameras (invited).

    PubMed

    MacPhee, A G; Dymoke-Bradshaw, A K L; Hares, J D; Hassett, J; Hatch, B W; Meadowcroft, A L; Bell, P M; Bradley, D K; Datte, P S; Landen, O L; Palmer, N E; Piston, K W; Rekow, V V; Hilsabeck, T J; Kilkenny, J D

    2016-11-01

    We report simulations and experiments that demonstrate an increase in spatial resolution of the NIF core diagnostic x-ray streak cameras by at least a factor of two, especially off axis. A design was achieved by using a corrector electron optic to flatten the field curvature at the detector plane and corroborated by measurement. In addition, particle in cell simulations were performed to identify the regions in the streak camera that contribute the most to space charge blurring. These simulations provide a tool for convolving synthetic pre-shot spectra with the instrument function so signal levels can be set to maximize dynamic range for the relevant part of the streak record.

  8. 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.

  9. The small saphenous vein and other 'neglected' veins of the popliteal fossa: a review.

    PubMed

    O'Donnell, T F; Iafrati, M D

    2007-01-01

    The small saphenous vein (SSV) and other veins in the popliteal fossa merit little discussion in the literature or in didactic programmes regarding their role in chronic venous insufficiency (CVI) and, in this sense, they are neglected. The purpose of this review is to present both duplex ultrasound findings and the associated clinical characteristics of patients with SSV reflux, from several large series. Both the anatomic variations and the epidemiology of the SSV, as well as other veins of the popliteal fossa, the gastrocnemius veins, Gocamini vein, popliteal area veins and popliteal vein, will be discussed. Findings from our review of the current available literature will demonstrate the important role that these veins play in association with CVI. The implications for open and endovenous surgery will be underlined.

  10. Tissue remodeling investigation in varicose veins

    PubMed Central

    Ghaderian, Sayyed Mohammad Hossein; Khodaii, Zohreh

    2012-01-01

    Although the etiology of varicose veins remains unknown, recent studies have focused on endothelial cell integrity and function because the endothelium regulates vessel tone and synthesizes many pro- and anti-inflammatory factors. The aim of this study was to investigate the evidence involving the endothelium in the development of varicose vein disease. In addition, tissue remodeling was investigated in varicose veins to determine the expression of different types of collagen. Tissue specimens of superficial varicose veins and control saphenous vein were used for immunohistochemical and transmission electron microscope (TEM). α-smooth muscle actin, and collagen I, III, IV antibodies were applied for immunohistochemical investigation. Findings of this study showed alterations of the intima, such as focal intimal discontinuity and denudation of endothelium; and the media, such as irregular arrangements of smooth muscle cells and collagen fibres in varicose veins. Our findings showed some changes in terms of distribution of types I, III and IV collagen in the intima and media of varicose vein walls compared with controls. These alterations to the media suggest that the pathological abnormality in varicose veins may be due to the loss of muscle tone as a result of the breakup of its regular structure by the collagen fibres. These findings only described some changes in terms of distribution of these types of collagen in the intima and media of varicose vein walls which may result in venous wall dysfunction in varicosis. PMID:24551759

  11. Small hepatic veins Budd-Chiari syndrome.

    PubMed

    Riggio, Oliviero; Marzano, Chiara; Papa, Alessia; Pasquale, Chiara; Gasperini, Maria Ludovica; Gigante, Antonietta; Valla, Dominique Charles; Plessier, Aurélie; Amoroso, Antonio

    2014-05-01

    Budd-Chiari syndrome is a rare disorder characterized by hepatic venous outflow obstruction at any level from the small hepatic veins to the atrio-caval junction, in the absence of heart failure or constrictive pericarditis. Various imaging modalities are available for investigating the gross hepatic vascular anatomy but there are rare forms of this disease where the obstruction is limited to the small intrahepatic veins, with normal appearance of the large hepatic veins at imaging. In this cases only a liver biopsy can demonstrate the presence of a small vessels outflow block. We report two cases of small hepatic veins Budd-Chiari syndrome.

  12. Clinically silent deep vein thrombosis in patients with superficial thrombophlebitis and varicose veins at legs.

    PubMed

    Jerkic, Zoran; Karic, Alen; Karic, Amela

    2009-01-01

    Although superficial thrombophlebitis is a common disorder until recently it was considered as benign disorder. Also it is associated with varicose vein at legs and it was treated effectively with conservative methods, walking and non-steroid anti-inflammatory drugs. Aims of our investigation were: determine frequency of clinically silent deep vein thrombosis at legs in patient with and without superficial thrombophlebitis, determine correlation between superficial thrombophlebitis and deep vein thrombosis regardless of localization of superficial thrombophlebitis in superficial veins of legs and determine adequacy and safety vein phlebography in early diagnosis clinically silent deep vein thrombosis in patients with superficial thrombophlebitis. Using flebography in prospective study was evaluated incidence of clinically silent deep vein thrombosis in 92 patients with varicose veins at legs. By phlebograpy in patients with varicose veins at legs and superficial thrombophlebitis at legs and without clinical signs of DVT at legs of the 49 patients we detected DVT in 12 patients (24, 48%), in three male and nine female. We detected localization of DVT in ilijacofemoral junction in 4,08% patients, although localization of DVT in femoropopliteal region was observed in 6, 12% patients and localization in crural region was in 14.28% patients. Localization of DVT at legs was detected in iliac vein in 16.66% patients, in femoral vein in 25% patients, popliteal vein 8.33% patients, anterior tibial vein 16.66%, posterior tibial vein in 25% and crural veins 8.33% patients. Also we deduced significant difference between two group of patients (chi2 = 10, 76). Such result proves thesis that in most patients with superficial thrombophlebitis and varicose veins is possibility of developing of DVT.

  13. 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.

  14. 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.

  15. Mach-zehnder based optical marker/comb generator for streak camera calibration

    DOEpatents

    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.

  16. Upgrades to the VISAR-streaked optical pyrometer (SOP) system on NIF

    NASA Astrophysics Data System (ADS)

    Manuel, A. M.; Millot, M.; Seppala, L. G.; Frieders, G.; Zeid, Z.; Christensen, K.; Celliers, P. M.

    2015-08-01

    The Velocity Interferometer System for Any Reflector (VISAR) is a critical diagnostic in Inertial Confinement Fusion and High Energy Density research as it has the ability to track shock fronts or interfaces moving 0.1-100 km/s with great accuracy. At the National Ignition Facility (NIF), the VISAR has recently been used successfully for implosion tuning and equation of state measurements. However, the initial design of the companion Streaked Optical Pyrometer (SOP) to measure spectral radiance - hence shock temperature - suffers from large background levels and poor spatial resolution. We report on an upgrade to improve the spatial resolution in the 560-640nm band by using custom lenses and replacing the Dove prism with a K-mirror and implementing a gating-circuit for the streak camera to reduce background signal. We envision that upgraded SOP will provide high quality data collection matching NIF VISAR's standards.

  17. 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.

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

    SciTech Connect

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

    2016-02-28

    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. (acoustooptics)

  19. A novel compact high speed x-ray streak camera (invited).

    PubMed

    Hares, J D; Dymoke-Bradshaw, A K L

    2008-10-01

    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.

  20. Simultaneous streak and frame interferometry for electron density measurements of laser produced plasmas

    SciTech Connect

    Quevedo, H. J. McCormick, M.; Wisher, M.; Bengtson, Roger D.; Ditmire, T.

    2016-01-15

    A system of two collinear probe beams with different wavelengths and pulse durations was used to capture simultaneously snapshot interferograms and streaked interferograms of laser produced plasmas. The snapshots measured the two dimensional, path-integrated, electron density on a charge-coupled device while the radial temporal evolution of a one dimensional plasma slice was recorded by a streak camera. This dual-probe combination allowed us to select plasmas that were uniform and axisymmetric along the laser direction suitable for retrieving the continuous evolution of the radial electron density of homogeneous plasmas. Demonstration of this double probe system was done by measuring rapidly evolving plasmas on time scales less than 1 ns produced by the interaction of femtosecond, high intensity, laser pulses with argon gas clusters. Experiments aimed at studying homogeneous plasmas from high intensity laser-gas or laser-cluster interaction could benefit from the use of this probing scheme.

  1. A comparison of flat-field measurement techniques for optical streak cameras

    SciTech Connect

    Montgomery, D.S.; Wiedwald, J.D.

    1988-08-01

    A technique for calibrating the flat-field response and geometric distortion of optical steak cameras using high-power lasers and electro-optic pulse shaping hardware was reported previously. The laser hardware provides a temporally-flat light pulse that can be used to calibrate streak cameras operating with sweep durations of 3- 10 ns. Although this technique is successful, the hardware involved is expensive and the process is complex. Based on the analysis of calibrations made at these fast sweep rates, we developed a new technique to measure the flat-field response of an optical streak camera using an array of visible light emitting diodes (LED) and a slow (/approximately/10..mu..s) sweep generator. We will discuss the new slow technique, and will present a comparison between calibration measurements made using the two techniques. 6 refs., 5 figs.

  2. 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.

  3. Stability and accuracy of the sweep rate measurements for LLNL optical streak cameras

    SciTech Connect

    Montgomery, D.S.

    1989-08-04

    Precise pulse shaping is vital for present and future high-power lasers that will attempt to achieve low-entropy laser-fusion implosions. Multichannel, streak-camera-based systems are used to make such measurements. Such systems must be accurately calibrated in order to correct for time-base and flat-field variations. We use an on-line calibration system in order to measure the sweep rate, and in our recent work we have evaluated the accuracy of this measurement technique. By analyzing a large number of calibrations, and the effect of noise on our measurement technique, we have concluded that the sweep rate for our streak camera systems is reproducible to a least {plus minus}1.2% and that our measurement technique contributes an additional {plus minus}0.5% uncertainty in the measurement. 18 refs., 3 figs., 1 tab.

  4. 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.

  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.

    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.

  6. Yellow fever in the Americas.

    PubMed

    Bryan, Charles S; Moss, Sandra W; Kahn, Richard J

    2004-06-01

    Dutch slave traders brought yellow fever to the Americas from Africa during the mid-seventeenth century. For the next two and a half centuries, the disease terrorized seaports throughout the Americas. Proof of the mosquito hypothesis was delayed because of two aspects of the disease: patients are viremic only during the first several days of clinical illness, and most mosquitoes require about 2 weeks of viral incubation before becoming infectious. Control of Aedes aegypti in urban centers failed to eliminate the disease because of its transmission by tree-hole-breeding mosquitoes that spend their winged lives mainly in forest canopies. Yellow fever continues to be a significant public health problem in parts of South America and Africa.

  7. Turbulent Dispersion of Film Coolant and Hot Streaks in a Turbine Vane Cascade

    DTIC Science & Technology

    2015-01-18

    turbine vane. The overall objective was to understand the turbulent mixing in a complex flow and develop tools to determine the non uniform temperature...distribution incident on a downstream turbine rotor. Magnetic resonance velocimetry provided the three component velocity distribution throughout a...Approved for Public Release; Distribution Unlimited Final Report: Turbulent Dispersion of Film Coolant and Hot Streaks in a Turbine Vane Cascade The

  8. Changes Over a Martian Year -- New Dark Slope Streaks in Lycus Sucli

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Now in its Extended Mission, Mars Global Surveyor (MGS) is into its second Mars year of systematic observations of the red planet. With the Extended Mission slated to run through April 2002, the Mars Orbiter Camera (MOC) is being used, among other things, to look for changes that have occurred in the past martian year. Because Mars is farther from the Sun than Earth, its year is longer--about 687 Earth days.

    The two pictures shown here cover the same portion of Lycus Sulci, a rugged, ridged terrain north of the giant Olympus Mons volcano. The interval between the pictures span 92% of a martian year (August 2, 1999 to April 27, 2001). Dark streaks considered to result from the avalanching of dry, fine, bright dust are seen in both images. The disruption of the surface by the avalanching materials is thought to cause them to appear darker than their surroundings, just as the 1997 bouncing of Mars Pathfinder's airbags and the tire tracks made by the Sojourner rover left darkened markings indicating where the martian soil had been disrupted and disturbed. The arrows in the April 2001 picture indicate eight new streaks that formed on these slopes in Lycus Sulci since August 1999. These observations suggest that a new streak forms approximately once per martian year per kilometer (about 0.62 miles) along a slope.

    In both images, north is toward the top/upper right and sunlight illuminates each from the left. Dark (as well bright) slope streaks are most common in the dust-covered martian regions of Tharsis, Arabia, and Elysium.

  9. Molecular characterization of Banana streak virus isolate from Musa Acuminata in China.

    PubMed

    Zhuang, Jun; Wang, Jian-Hua; Zhang, Xin; Liu, Zhi-Xin

    2011-12-01

    Banana streak virus (BSV), a member of genus Badnavirus, is a causal agent of banana streak disease throughout the world. The genetic diversity of BSVs from different regions of banana plantations has previously been investigated, but there are relatively few reports of the genetic characteristic of episomal (non-integrated) BSV genomes isolated from China. Here, the complete genome, a total of 7722bp (GenBank accession number DQ092436), of an isolate of Banana streak virus (BSV) on cultivar Cavendish (BSAcYNV) in Yunnan, China was determined. The genome organises in the typical manner of badnaviruses. The intergenic region of genomic DNA contains a large stem-loop, which may contribute to the ribosome shift into the following open reading frames (ORFs). The coding region of BSAcYNV consists of three overlapping ORFs, ORF1 with a non-AUG start codon and ORF2 encoding two small proteins are individually involved in viral movement and ORF3 encodes a polyprotein. Besides the complete genome, a defective genome lacking the whole RNA leader region and a majority of ORF1 and which encompasses 6525bp was also isolated and sequenced from this BSV DNA reservoir in infected banana plants. Sequence analyses showed that BSAcYNV has closest similarity in terms of genome organization and the coding assignments with an BSV isolate from Vietnam (BSAcVNV). The corresponding coding regions shared identities of 88% and -95% at nucleotide and amino acid levels, respectively. Phylogenetic analysis also indicated BSAcYNV shared the closest geographical evolutionary relationship to BSAcVNV among sequenced banana streak badnaviruses.

  10. 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.

  11. Streak-camera recording of simultaneous optical and x-ray signals

    SciTech Connect

    Lerche, R.A.; Medecki, H.; Phillips, G.E.; Thomas, S.W.

    1981-04-20

    An S-1 optical streak camera with 10-ps (optical) temporal resolution simultaneously records reflected 1.06-..mu..m laser light and suprathermal (> 30 keV) x rays from laser fusion targets. To make these measurements, the camera x-ray sensitivity is increased 30-fold without significant loss of temporal resolution by increasing the effective slit width from the normal 50 ..mu..m to 1500 ..mu..m. The measurement system is described and sample data are presented.

  12. 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.

  13. A new streaked soft x-ray imager for the National Ignition Facility

    DOE PAGES

    Benstead, J.; Moore, A. S.; Ahmed, M. F.; ...

    2016-05-27

    Here, a new streaked soft x-ray imager has been designed for use on high energy-density (HED) physics experiments at the National Ignition Facility based at the Lawrence Livermore National Laboratory. This streaked imager uses a slit aperture, single shallow angle reflection from a nickel mirror, and soft x-ray filtering to, when coupled to one of the NIF’s x-ray streak cameras, record a 4× magnification, one-dimensional image of an x-ray source with a spatial resolution of less than 90 μm. The energy band pass produced depends upon the filter material used; for the first qualification shots, vanadium and silver-on-titanium filters weremore » used to gate on photon energy ranges of approximately 300–510 eV and 200–400 eV, respectively. A two-channel version of the snout is available for x-ray sources up to 1 mm and a single-channel is available for larger sources up to 3 mm. Both the one and two-channel variants have been qualified on quartz wire and HED physics target shots.« less

  14. A streaked X-ray spectroscopy platform for rapidly heated, near-solid density plasmas

    NASA Astrophysics Data System (ADS)

    Stillman, C. R.; Nilson, P. M.; Ivancic, S. T.; Mileham, C.; Begishev, I. A.; Junquist, R. K.; Nelson, D. J.; Froula, D. H.

    2016-11-01

    A picosecond, time-resolved, x-ray spectroscopy platform was developed to study the thermal line emission from rapidly heated solid targets containing buried aluminum or iron layers. The targets were driven by high-contrast 1ω or 2ω laser pulses at focused intensities up to 1 × 1019 W/cm2. The experimental platform combines time-integrating and time-resolved x-ray spectrometers. Picosecond time resolution was achieved with a pair of ultrafast x-ray streak cameras coupled to high-throughput Hall spectrometers. Time-integrated spectra were collected on each shot to correct the streaked data for variations in x-ray photocathode spectral sensitivity. The time-integrated spectrometer uses three elliptical crystals to disperse x rays with energies between 800 and 2100 eV with moderate (E/ΔE ˜ 450) resolving power. The streaked spectrometers accept four interchangeable conical crystals with higher resolving power (E/ΔE ˜ 650) to measure the brightest thermal lines in the 1300 to 1700 eV spectral range.

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

    PubMed Central

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

    2016-01-01

    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

  16. 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.

  17. Signal-to-noise performance analysis of streak tube imaging lidar systems. I. Cascaded model.

    PubMed

    Yang, Hongru; Wu, Lei; Wang, Xiaopeng; Chen, Chao; Yu, Bing; Yang, Bin; Yuan, Liang; Wu, Lipeng; Xue, Zhanli; Li, Gaoping; Wu, Baoning

    2012-12-20

    Streak tube imaging lidar (STIL) is an active imaging system using a pulsed laser transmitter and a streak tube receiver to produce 3D range and intensity imagery. The STIL has recently attracted a great deal of interest and attention due to its advantages of wide azimuth field-of-view, high range and angle resolution, and high frame rate. This work investigates the signal-to-noise performance of STIL systems. A theoretical model for characterizing the signal-to-noise performance of the STIL system with an internal or external intensified streak tube receiver is presented, based on the linear cascaded systems theory of signal and noise propagation. The STIL system is decomposed into a series of cascaded imaging chains whose signal and noise transfer properties are described by the general (or the spatial-frequency dependent) noise factors (NFs). Expressions for the general NFs of the cascaded chains (or the main components) in the STIL system are derived. The work presented here is useful for the design and evaluation of STIL systems.

  18. 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.

  19. 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.

  20. 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.

  1. Picosecond Streaked K-Shell Spectroscopy of Near Solid-Density Aluminum Plasmas

    NASA Astrophysics Data System (ADS)

    Stillman, C. R.; Nilson, P. M.; Ivancic, S. T.; Mileham, C.; Froula, D. H.; Golovkin, I. E.

    2016-10-01

    The thermal x-ray emission from rapidly heated solid targets containing a buried-aluminum layer was measured. The targets were driven by high-contrast 1 ω or 2 ω laser pulses at focused intensities up to 1 ×1019W/Wcm2 cm2 . A streaked x-ray spectrometer recorded the Al Heα and lithium-like satellite lines with 2-ps temporal resolution and moderate resolving power (E/E ΔE 700). Time-integrated measurements over the same spectral range were used to correct the streaked data for variations in photocathode sensitivity. Line widths and intensity ratios from the streaked data were interpreted using a collisional radiative atomic model to provide the average plasma conditions in the buried layer as a function of time. It was observed that the resonance line tends toward lower photon energies at high electron densities. The measured shifts will be compared to predicted shifts from Stark-operator calculations at the inferred plasma conditions. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944, the office of Fusion Energy Sciences Award Number DE-SC0012317, and the Stewardship Science Graduate Fellowship Grant Number DE-NA0002135.

  2. A new streaked soft x-ray imager for the National Ignition Facility

    SciTech Connect

    Benstead, J.; Moore, A. S.; Ahmed, M. F.; Morton, J.; Guymer, T. M.; Pardini, T.; Soufli, R.; Hibbard, R. L.; Bailey, C. G.; Bell, P. M.; Hau-Riege, S.; Bedzyk, M.; Shoup, III, M. J.; Reagan, S.; Agliata, T.; Jungquist, R.; Schmidt, D. W.; Kot, L. B.; Garbett, W. J.; Rubbery, M. S.; Skidmore, J. W.; Gullikson, E.; Salmassi, F.

    2016-05-27

    Here, a new streaked soft x-ray imager has been designed for use on high energy-density (HED) physics experiments at the National Ignition Facility based at the Lawrence Livermore National Laboratory. This streaked imager uses a slit aperture, single shallow angle reflection from a nickel mirror, and soft x-ray filtering to, when coupled to one of the NIF’s x-ray streak cameras, record a 4× magnification, one-dimensional image of an x-ray source with a spatial resolution of less than 90 μm. The energy band pass produced depends upon the filter material used; for the first qualification shots, vanadium and silver-on-titanium filters were used to gate on photon energy ranges of approximately 300–510 eV and 200–400 eV, respectively. A two-channel version of the snout is available for x-ray sources up to 1 mm and a single-channel is available for larger sources up to 3 mm. Both the one and two-channel variants have been qualified on quartz wire and HED physics target shots.

  3. A new streaked soft x-ray imager for the National Ignition Facility.

    PubMed

    Benstead, J; Moore, A S; Ahmed, M F; Morton, J; Guymer, T M; Soufli, R; Pardini, T; Hibbard, R L; Bailey, C G; Bell, P M; Hau-Riege, S; Bedzyk, M; Shoup, M J; Reagan, S; Agliata, T; Jungquist, R; Schmidt, D W; Kot, L B; Garbett, W J; Rubery, M S; Skidmore, J W; Gullikson, E; Salmassi, F

    2016-05-01

    A new streaked soft x-ray imager has been designed for use on high energy-density (HED) physics experiments at the National Ignition Facility based at the Lawrence Livermore National Laboratory. This streaked imager uses a slit aperture, single shallow angle reflection from a nickel mirror, and soft x-ray filtering to, when coupled to one of the NIF's x-ray streak cameras, record a 4× magnification, one-dimensional image of an x-ray source with a spatial resolution of less than 90 μm. The energy band pass produced depends upon the filter material used; for the first qualification shots, vanadium and silver-on-titanium filters were used to gate on photon energy ranges of approximately 300-510 eV and 200-400 eV, respectively. A two-channel version of the snout is available for x-ray sources up to 1 mm and a single-channel is available for larger sources up to 3 mm. Both the one and two-channel variants have been qualified on quartz wire and HED physics target shots.

  4. 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

    2016-02-05

    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.

  5. Development of a Data Reduction Algorithm for Optical Wide Field Patrol (OWL) II: Improving Measurement of Lengths of Detected Streaks

    NASA Astrophysics Data System (ADS)

    Park, Sun-Youp; Choi, Jin; Roh, Dong-Goo; Park, Maru; Jo, Jung Hyun; Yim, Hong-Suh; Park, Young-Sik; Bae, Young-Ho; Park, Jang-Hyun; Moon, Hong-Kyu; Choi, Young-Jun; Cho, Sungki; Choi, Eun-Jung

    2016-09-01

    As described in the previous paper (Park et al. 2013), the detector subsystem of optical wide-field patrol (OWL) provides many observational data points of a single artificial satellite or space debris in the form of small streaks, using a chopper system and a time tagger. The position and the corresponding time data are matched assuming that the length of a streak on the CCD frame is proportional to the time duration of the exposure during which the chopper blades do not obscure the CCD window. In the previous study, however, the length was measured using the diagonal of the rectangle of the image area containing the streak; the results were quite ambiguous and inaccurate, allowing possible matching error of positions and time data. Furthermore, because only one (position, time) data point is created from one streak, the efficiency of the observation decreases. To define the length of a streak correctly, it is important to locate the endpoints of a streak. In this paper, a method using a differential convolution mask pattern is tested. This method can be used to obtain the positions where the pixel values are changed sharply. These endpoints can be regarded as directly detected positional data, and the number of data points is doubled by this result.

  6. 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.

  7. 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...

  8. 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...

  9. Vascular Streak Dieback of cacao in Southeast Asia and Melanesia: in planta detection of the pathogen and a new taxonomy.

    PubMed

    Samuels, Gary J; Ismaiel, Adnan; Rosmana, Ade; Junaid, Muhammad; Guest, David; McMahon, Peter; Keane, Philip; Purwantara, Agus; Lambert, Smilja; Rodriguez-Carres, Marianela; Cubeta, Marc A

    2012-01-01

    Vascular Streak Dieback (VSD) disease of cacao (Theobroma cacao) in Southeast Asia and Melanesia is caused by a basidiomycete (Ceratobasidiales) fungus Oncobasidium theobromae (syn. =Thanatephorus theobromae). The most characteristic symptoms of the disease are green-spotted leaf chlorosis or, commonly since about 2004, necrotic blotches, followed by senescence of leaves beginning on the second or third flush behind the shoot apex, and blackening of infected xylem in the vascular traces at the leaf scars resulting from the abscission of infected leaves. Eventually the shoot apex is killed and infected branches die. In susceptible cacao the fungus may grow through the xylem down into the main stem and kill a mature cacao tree. Infections in the stem of young plants prior to the formation of the first 3-4 lateral branches usually kill the plant. Basidiospores released from corticioid basidiomata developed on leaf scars or along cracks in the main vein of infected leaves infect young leaves. The pathogen commonly infects cacao but there are rare reports from avocado. As both crops are introduced to the region, the pathogen is suspected to occur asymptomatically in native vegetation. The pathogen is readily isolated but cultures cannot be maintained. In this study, DNA was extracted from pure cultures of O. theobromae obtained from infected cacao plants sampled from Indonesia. The internal transcribed spacer region (ITS), consisting of ITS1, 5.8S ribosomal RNA and ITS2, and a portion of nuclear large subunit (LSU) were sequenced. Phylogenetic analysis of ITS sequences placed O. theobromae sister to Ceratobasidium anastomosis groups AG-A, AG-Bo, and AG-K with high posterior probability. Therefore the new combination Ceratobasidium theobromae is proposed. A PCR-based protocol was developed to detect and identify C. theobromae in plant tissue of cacao enabling early detection of the pathogen in plants. A second species of Ceratobasidium, Ceratobasidium ramicola

  10. Element transport in veins during serpentinization

    NASA Astrophysics Data System (ADS)

    Schwarzenbach, E. M.; Beard, J. S.; Caddick, M. J.

    2013-12-01

    Serpentinization of ultramafic rocks has wide ranging implications for the petrology, rheology, and petrophysical properties of the oceanic lithosphere. During hydration of the peridotite, fluid-rock ratios and temperature control mineral formation in the veins. We studied a partly serpentinized peridotite from the Santa Elena ophiolite complex in Costa Rica and tracked element mobility during water-rock interaction. Serpentinization of the studied harzburgite is around 30 to 40%, with serpentinization of olivine being more advanced than serpentinization of orthopyroxene. Element mapping and point analyses show that the veins preserve characteristic element distributions within orthopyroxene and olivine, and with distance to orthopyroxene-hosted serpentine veins. With increasing distance from the orthopyroxene the following vein assemblages were observed in olivine: pure serpentine veins, serpentine + brucite veins, serpentine + brucite + magnetite veins. Veins are enriched in SiO2 in the proximity of orthopyroxene suggesting that a net transfer of SiO2 takes place from serpentinizing orthopyroxene to olivine. The magnetite-bearing serpentine veins mostly consist of Mg-rich serpentine (Mg# = 90 - 95) and Fe-rich brucite (Mg# = 70 - 75) finely intergrown. In contrast, the center of these veins contains a thin zone of high-Mg serpentine (Mg# 97), and high-Mg brucite (Mg# 92 - 94) next to magnetite. We infer from thermodynamic calculations that these mineral assemblages are controlled by H2O activity and low SiO2 activities. Within orthopyroxene, serpentine (Mg# = 84 - 89) with an elevated Al2O3 content (< 4.14wt.%) was detected, but talc was absent, indicating net loss of SiO2 from orthopyroxene during serpentinization. CaO and Al2O3 migrate from orthopyroxene, but occur only as trace components in serpentine at > 100 μm and > 200 μm, respectively, from the orthopyroxene. We infer that brucite is not stable in close proximity to orthopyroxene due to elevated SiO2

  11. [Preduodenal portal vein (author's transl)].

    PubMed

    Tovar, J A; Benavent, M; Bachiller, C; Díez-Pardo, J A

    1978-01-01

    Three cases of preduodenal portal vein (PDPV) observed in newborns and young infants are reported. In two patients the diagnosis was made during operations for duodenal stenosis and in the remaining one while operating for midgut volvulus and necrosis. In no case was the PDPV responsible for the clinical picture but in all three patients it was accompanied by other causes of obstruction: annular pancreas, extrinsic adhesive bands and malrotation. In one case there was also an asplenia, and polisplenia was present in another one. Both had malrotation and some degree of abnormal visceral asimmetry. The incidence of associated malformations in 52 previously reported cases is analyzed, and the more convincing embriological explanation for this anomaly is commented upon.

  12. Assessment and management of patients with varicose veins.

    PubMed

    Allen, Louise

    Varicose veins are enlarged superficial veins found in the legs. This article explores the anatomy and physiology of the venous system to assist nurses to assess, manage and treat patients with varicose veins.

  13. Lung Pathology in Pediatric Pulmonary Vein Stenosis.

    PubMed

    Pogoriler, Jennifer E; Kulik, Thomas J; Casey, Alicia M; Baird, Christopher W; Mullen, Mary P; Jenkins, Kathy J; Vargas, Sara O

    2016-01-01

    Pulmonary vein stenosis is a rare progressive narrowing of the extrapulmonary pulmonary veins, presenting predominantly in infancy and virtually always lethal. It typically arises following repair of congenital heart disease, particularly anomalous pulmonary venous return. Histologic characterization of pediatric pulmonary vein stenosis, not previously well described, may provide insight into the disease pathobiology. We retrieved archival lung specimens (biopsy, explant, or autopsy) from patients with pediatric pulmonary vein stenosis. Medical records were reviewed. Microscopic examination included hematoxylin and eosin (H&E)-stained slides, and for a subset of patients, elastic, trichrome, smooth-muscle actin, and D2-40. Groups with different clinical disease features were compared using Fisher's exact test. A total of 33 patients (median age, 7 months) had available tissue and 52% had congenital heart disease; 18% were premature. Within the lungs, interlobular septal veins showed thickened muscular coats (in 58%), proliferation/tortuosity (in 6%), and fibromyxoid intimal proliferation (in 3%). Associated arterial hypertensive changes were seen in 30 (91%). The one patient with intrapulmonary venous fibromyxoid intimal proliferation was the only patient with apparent primary familial disease. Lymphangiectasia and arterial medial hypertrophy were histologic features that correlated with clinical grouping. We conclude that in pediatric pulmonary vein stenosis, intrapulmonary pulmonary veins commonly show muscular thickening, best interpreted as venous hypertensive remodeling. Fibromyxoid intimal proliferation resembling that of the extrapulmonary pulmonary veins is uncommon. Awareness of intrapulmonary features in various clinical subtypes of pulmonary vein stenosis may be diagnostically and therapeutically informative considering that current catheter-based and surgical therapy is directed at the extrapulmonary component of pulmonary vein stenosis.

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

    PubMed

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

    2012-11-01

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

  15. Isolation of yellow catfish β-actin promoter and generation of transgenic yellow catfish expressing enhanced yellow fluorescent protein.

    PubMed

    Ge, Jiachun; Dong, Zhangji; Li, Jingyun; Xu, Zhiqiang; Song, Wei; Bao, Jie; Liang, Dong; Li, Junbo; Li, Kui; Jia, Wenshuang; Zhao, Muzi; Cai, Yongxiang; Yang, Jiaxin; Pan, Jianlin; Zhao, Qingshun

    2012-10-01

    Yellow catfish (Pelteobagrus fulvidraco Richardson) is one of the most important freshwater farmed species in China. However, its small size and slow growth rate limit its commercial value. Because genetic engineering has been a powerful tool to develop and improve fish traits for aquaculture, we performed transgenic research on yellow catfish in order to increase its size and growth rate. Performing PCR with degenerate primers, we cloned a genomic fragment comprising 5'-flanking sequence upstream of the initiation codon of β-actin gene in yellow catfish. The sequence is 1,017 bp long, containing the core sequence of proximal promoter including CAAT box, CArG motif and TATA box. Microinjecting the transgene construct Tg(beta-actin:eYFP) of the proximal promoter fused to enhanced yellow fluorescent protein (eYFP) reporter gene into zebrafish and yellow catfish embryos, we found the promoter could drive the reporter to express transiently in both embryos at early development. Screening the offspring of five transgenic zebrafish founders developed from the embryos microinjected with Tg(ycbeta-actin:mCherry) or 19 yellow catfish founders developed from the embryos microinjected with Tg(beta-actin:eYFP), we obtained three lines of transgenic zebrafish and one transgenic yellow catfish, respectively. Analyzing the expression patterns of the reporter genes in transgenic zebrafish (Tg(ycbeta-actin:mCherry)nju8/+) and transgenic yellow catfish (Tg(beta-actin:eYFP)nju11/+), we found the reporters were broadly expressed in both animals. In summary, we have established a platform to make transgenic yellow catfish using the proximal promoter of its own β-actin gene. The results will help us to create transgenic yellow catfish using "all yellow catfish" transgene constructs.

  16. 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

    2015-10-02

    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.

  17. 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...

  18. 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...

  19. 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.

  20. Atypical tryptamine receptors in sheep pulmonary vein.

    PubMed Central

    Eyre, P

    1975-01-01

    Both the pulmonary artery and vein of the sheep contracted dose-dependently to histamine, carbamoylcholine, prostaglandin F2a, noradrenaline and bradykinin and relaxed in the presence of isoprenaline or prostaglandin E1. 2 The effect of 5-hydroxytryptamine (5-HT) on the artery was consistently to produce dose-dependent contractions without tachyphylaxis. The effect on the vein was biphasic. 5HT 5 X 10(-10) to 5 X 10(-8) M relaxed the partially constricted vein. 5-HT 10(-7) to 10(-6) m caused brief venoconstriction followed by relaxation. 5-HT greater than 10(-6) M caused dose-related contraction of the vein. 3 Methysergide effectively blocked the contractile response of the artery to 5-HT, but only weakly inhibited the contractions of the vein (dose-ratio less than 20). 4 Each of ten antagonists tested failed to inhibit the 5-HT-induced relaxation of the vein. Sheep pulmonary vein possesses tryptamine receptors which mediate relaxation and which are not of the classicl M- or D-type. These receptors appear not to be involved directly or indirectly with responses to acetylcholine, catecholamines, histamine or prostaglandins. PMID:1203621

  1. Preduodenal portal vein in the adult.

    PubMed

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

    2000-09-01

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

  2. Radiological features of azygous vein aneurysm.

    PubMed

    Choudhary, Arabinda Kumar; Moore, Michael

    2014-04-01

    Mediastinal masses are most commonly associated with malignancy. Azygous vein aneurysm is a very rare differential diagnosis of mediastinal mass. We report here three cases of azygous vein aneurysm including children and adult patients. In the pediatric patient it was further complicated by thrombosis and secondary pulmonary embolism. We describe the radiological features on CXR, MRI, CT, PET-CT, US and angiogram and their differential diagnosis. Imaging findings of continuity with azygous vein, layering of contrast medium on enhanced CT and dynamic MRA showing filling of the mass at the same time as the azygous vein without prior enhancement will be strongly suggestive of azygous vein aneurysm with transtracheal ultrasound being the definitive test in these patients. It is important to keep a vascular origin mass in the differential diagnosis of mediastinal masses. Also, in young healthy patients with pulmonary embolism, a vascular etiology such as azygous vein aneurysm should be carefully evaluated. This article will help the clinicians to learn about the imaging features of azygous vein aneurysm on different imaging modalities.

  3. A Reappraisal of Saphenous Vein Grafting

    PubMed Central

    Yuan, Shi-Min; Jing, Hua

    2011-01-01

    Autologous saphenous vein grafting has been broadly used as a bypass conduit, interposition graft, and patch graft in a variety of operations in cardiac, thoracic, neurovascular, general vascular, vascular access, and urology surgeries, since they are superior to prosthetic veins. Modified saphenous vein grafts (SVG), including spiral and cylindrical grafts, and vein cuffs or patches, are employed in vascular revascularization to satisfy the large size of the receipt vessels or to obtain a better patency. A loop SVG helps flap survival in a muscle flap transfer in plastic and reconstructive surgery. For dialysis or transfusion purposes, a straight or loop arteriovenous fistula created in the forearm or the thigh with an SVG has acceptable patency. The saphenous vein has even been used as a stent cover to minimize the potential complications of standard angioplasty technique. However, the use of saphenous vein grafting is now largely diminished in treating cerebrovascular disorders, superior vena cava syndrome, and visceral revascularization due to the introduction of angioplasty and stenting techniques. The SVG remains the preferable biomaterial in coronary artery bypass, coronary ostioplasty, free flap transfer, and surgical treatment of Peyronie disease. Implications associated with saphenous vein grafting in vascular access surgery for the purpose of dialysis and chemotherapy are considerable. Vascular cuffs and patches have been developed as an important and effective means of enhancing the patency rates of the grafts by linking the synthetic material to the receipt vessel. In addition, saphenous veins can be a cell source for tissue engineering. We review the versatile roles that saphenous vein grafting has played as well as its current status in therapy. PMID:21245602

  4. [Yellow fever epidemiology in Brazil].

    PubMed

    Mondet, B

    2001-08-01

    We have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in Brazil from 1954 to 1972 and especially from 1973 to 1999. This study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. The endemic area is located within the Amazon basin; here cases are scattered and generally limited in number. However, there are also "foci of endemic emergence" within this area, where cases are less rare, although occurrence remains irregular. The epidemic area is for the most part situated outside the Amazon basin, to the north east and particularly to the south. It has been divided into two parts according to whether the occurrence of yellow fever is cyclic or sporadic. The epidemics, which are all sylvatic, follow either a circular path (in the forest area) or a linear path (in forest-galleries of the savannah area). The study of the development of the 3 main epidemics (1972-74; 1979-82; 1986-92) in the cyclic emergence area showed that, on each occasion, the yellow fever virus appeared at a particularly active outbreak site located in the "serra dos Carajás", and from there, it followed the courses of the Tocantins and Araguaia rivers upstream, moving southwards during the "pre-epidemic phase" which may be visible due to the occurrence of a few cases, or may remain invisible. Subsequently the virus reached the emergence area, where it appeared in the form of epidemics. In this zone, it also followed privileged south-western pathways, moving from one hydraulic basin to another along the upstream courses of the rivers. Almost exactly the same pathways have been identified for each of the 3 epidemics studied. The distances travelled by the virus over a period of one year--when it goes rapidly--can reach several hundred kilometers. On the other hand, it may be stationary for a period of one or two consecutive years, occasionally three, remaining

  5. Yellow nail syndrome: a review.

    PubMed

    Vignes, Stéphane; Baran, Robert

    2017-02-27

    Yellow nail syndrome (YNS; OMIM 153300, ORPHA662) is a very rare disorder that almost always occurs after 50 years of age but a juvenile or familial form has also been observed. YNS is diagnosed based on a triad associating yellow nail discoloration, pulmonary manifestations (chronic cough, bronchiectasia, pleural effusion) and lower limb lymphedema. Chronic sinusitis is frequently associated with the triad. YNS etiology remains unknown but a role of lymphatic impairment is usually evoked. YNS is more frequently isolated but may be associated in rare cases with autoimmune diseases, other clinical manifestations implicating lymphatic functions or cancer and, hence, is also considered a paraneoplastic syndrome. YNS management is symptomatic and not codified. YNS can resolve spontaneously. Oral vitamin E alone or even better when associated with triazole antifungals may achieve partial or total disappearance of nail discoloration. Pleural effusion can be treated surgically, with decortication/pleurectomy or pleurodesis. Antibiotic prophylaxis is prescribed for bronchiectasia with chronic sputum production. Lymphedema treatment is based on low-stretch bandages and the wearing of elastic compression garments combined with skin care, exercises and, as needed, manual lymph drainage.

  6. 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.

  7. A Virus-Derived Stacked RNAi Construct Confers Robust Resistance to Cassava Brown Streak Disease.

    PubMed

    Beyene, Getu; Chauhan, Raj Deepika; Ilyas, Muhammad; Wagaba, Henry; Fauquet, Claude M; Miano, Douglas; Alicai, Titus; Taylor, Nigel J

    2016-01-01

    Cassava brown streak disease (CBSD) threatens food and economic security for smallholder farmers throughout East and Central Africa, and poses a threat to cassava production in West Africa. CBSD is caused by two whitefly-transmitted virus species: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) (Genus: Ipomovirus, Family Potyviridae). Although varying levels of tolerance have been achieved through conventional breeding, to date, effective resistance to CBSD within East African cassava germplasm has not been identified. RNAi technology was utilized to integrate CBSD resistance into the Ugandan farmer-preferred cassava cultivar TME 204. Transgenic plant lines were generated expressing an inverted repeat construct (p5001) derived from coat-protein (CP) sequences of CBSV and UCBSV fused in tandem. Northern blots using probes specific for each CP sequence were performed to characterize 169 independent transgenic lines for accumulation of CP-derived siRNAs. Transgenic plant lines accumulating low, medium and high levels of siRNAs were bud graft challenged with the virulent CBSV Naliendele isolate alone or in combination with UCBSV. Resistance to CBSD in the greenhouse directly correlated to levels of CP-derived siRNAs as determined by visual assessment of leaf and storage root symptoms, and RT-PCR diagnosis for presence of the pathogens. Low expressing lines were found to be susceptible to CBSV and UCBSV, while medium to high accumulating plant lines were resistant to both virus species. Absence of detectable virus in the best performing p5001 transgenic lines was further confirmed by back-inoculation via sap or graft challenge to CBSD susceptible Nicotiana benthamiana and cassava cultivar 60444, respectively. Data presented shows robust resistance of transgenic p5001 TME 204 lines to both CBSV and UCBSV under greenhouse conditions. Levels of resistance correlated directly with levels of transgene derived siRNA expression such that the

  8. 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.

  9. A Virus-Derived Stacked RNAi Construct Confers Robust Resistance to Cassava Brown Streak Disease

    PubMed Central

    Beyene, Getu; Chauhan, Raj Deepika; Ilyas, Muhammad; Wagaba, Henry; Fauquet, Claude M.; Miano, Douglas; Alicai, Titus; Taylor, Nigel J.

    2017-01-01

    Cassava brown streak disease (CBSD) threatens food and economic security for smallholder farmers throughout East and Central Africa, and poses a threat to cassava production in West Africa. CBSD is caused by two whitefly-transmitted virus species: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) (Genus: Ipomovirus, Family Potyviridae). Although varying levels of tolerance have been achieved through conventional breeding, to date, effective resistance to CBSD within East African cassava germplasm has not been identified. RNAi technology was utilized to integrate CBSD resistance into the Ugandan farmer-preferred cassava cultivar TME 204. Transgenic plant lines were generated expressing an inverted repeat construct (p5001) derived from coat-protein (CP) sequences of CBSV and UCBSV fused in tandem. Northern blots using probes specific for each CP sequence were performed to characterize 169 independent transgenic lines for accumulation of CP-derived siRNAs. Transgenic plant lines accumulating low, medium and high levels of siRNAs were bud graft challenged with the virulent CBSV Naliendele isolate alone or in combination with UCBSV. Resistance to CBSD in the greenhouse directly correlated to levels of CP-derived siRNAs as determined by visual assessment of leaf and storage root symptoms, and RT-PCR diagnosis for presence of the pathogens. Low expressing lines were found to be susceptible to CBSV and UCBSV, while medium to high accumulating plant lines were resistant to both virus species. Absence of detectable virus in the best performing p5001 transgenic lines was further confirmed by back-inoculation via sap or graft challenge to CBSD susceptible Nicotiana benthamiana and cassava cultivar 60444, respectively. Data presented shows robust resistance of transgenic p5001 TME 204 lines to both CBSV and UCBSV under greenhouse conditions. Levels of resistance correlated directly with levels of transgene derived siRNA expression such that the

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

    PubMed

    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/cm(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.

  11. Modes on a short SPEAR bunch as observed with a streak camera

    SciTech Connect

    Sabersky, A.P.; Donald, M.H.R.

    1981-02-01

    The longitudinal structure of electron bunches in the storage ring SPEAR on a single pass was studied with time resolution approx. 10 ps. The measuring instrument used is an image-converter streak camera, a specialized device heretofore used mostly by laser workers. Unexpectedly, under some conditions the charge in a single RF bucket breaks up into two short sub-bunches which seem to rotate about a common center in energy-phase space. No evidence is seen for other, higher-frequency structure on the bunches.

  12. 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.

  13. Inoculation and virulence assay for bacterial blight and bacterial leaf streak of rice.

    PubMed

    Yang, Bing; Bogdanove, Adam

    2013-01-01

    Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc) cause bacterial blight and bacterial leaf streak in rice, respectively. Despite being very closely related, the pathogens colonize different tissues and cause distinct diseases. The diseases are economically important and also serve as model systems for studying plant-bacterial interactions. Here we describe protocols for Xoo and Xoc inoculation and disease scoring methods that are appropriate to their different modes of infection. These methods are routinely used to evaluate pathogen virulence or host responses under controlled environmental conditions.

  14. Design of a streaked radiography instrument for ICF ablator tuning measurements.

    PubMed

    Olson, R E; Hicks, D G; Spears, B K; Celliers, P M; Holder, J P; Landen, O L; Geissel, M; Kellogg, J W; Bennett, G R; Edens, A D; Atherton, B W; Leeper, R J

    2008-10-01

    A streaked radiography diagnostic has been proposed as a technique to determine the ablator mass remaining in an inertial confinement fusion ignition capsule at peak velocity. This instrument, the "HXRI-5," has been designed to fit within a National Ignition Facility Diagnostic Instrument Manipulator. The HXRI-5 will be built at Sandia National Laboratories (SNL), and initial testing will be done at the SNL Z-Beamlet Facility. In this paper, we will describe the National Ignition Campaign requirements for this diagnostic, the instrument design, and the planned test experiments.

  15. Study of the Performance of a Streaked Optical Pyrometer System for Temperature Measurement of Shocked Materials

    NASA Astrophysics Data System (ADS)

    Zhang, Chen; Liu, Hao; Wang, Zhebin; Jiang, Xiaohua; Zhang, Huige; Liu, Yonggang; Li, Zhichao; Li, Sanwei; Yang, Dong; Ding, Yongkun; Zhao, Bin; Hu, Guangyue; Zheng, Jian

    2014-06-01

    A streaked optical pyrometer (SOP) is developed and calibrated for the measurement of the temperature of shocked materials. In order to achieve a higher relative sensitivity, a one-channel scheme is adopted for the system. The system is calibrated with a shocked step-shaped aluminum sample in the SG-III prototype laser facility. The relation between the count number in the detection system and the sample temperature is thus obtained, which can be adopted to infer the temperature of any shocked materials in future experiments.

  16. Progression of Thrombus in Portal Vein, Superior Mesenteric Vein, and Splenic Vein Even on Anticoagulation in a Patient with Ascending Colonic Malignancy with Liver Metastasis: Portal Vein Thrombosis versus Portal Vein Tumor Thrombosis.

    PubMed

    Sule, Ashish; Borja, Annamarie; Chin, Tay Jam

    2016-12-01

    Portal vein thrombosis (PVT) in a setting of liver metastasis is not easy to treat as it may be portal vein tumor thrombus (PVTT). A 77-year-old male patient was diagnosed as ascending colon carcinoma, underwent right hemicolectomy in 1991 with a recurrence in July 2009. In August 2009, he underwent computed tomography (CT) scan of the abdomen which showed evidence of superior mesenteric vein thrombosis with no liver metastasis. He was started with anticoagulation and decision was to treat long term. He was admitted with mesenteric artery ischemic symptoms in February 2012 on anticoagulation. CT scan abdomen and pelvis in February 2012 showed tumor thrombus involving the superior mesenteric vein, portal vein, and splenic vein with hepatic metastasis. His tumor marker chorioembryonic antigen was 34 µg/L. He was continued on anticoagulation. A repeat CT scan abdomen after 2 years (in January 2014) showed, increase in size of hepatic metastasis, extensive thrombus involving the superior mesenteric vein, portal vein, and splenic vein with collaterals. Mesentery was congested due to extensive superior mesenteric vein thrombus. He finally succumbed in June 2014. It is very important to differentiate PVT from PVTT as the prognosis is different. PVTT progresses despite of long-term anticoagulation with poor prognosis.

  17. Who Is at Risk for Varicose Veins?

    MedlinePlus

    ... better within 3 to 12 months of delivery. Overweight or Obesity Being overweight or obese can put extra pressure on your ... lead to varicose veins. For more information about overweight and obesity, go to the Health Topics Overweight ...

  18. Varicose veins - what to ask your doctor

    MedlinePlus

    ... what to ask your doctor References Goldman MP, Weiss RA. Phleblogy and treatment of leg veins. In: ... and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

  19. [Retinal vein occlusion in a young patient].

    PubMed

    Zemba, Mihail; Ochinciuc, Uliana; Sarbu, Laura; Avram, Corina; Camburu, Raluca; Stamate, Alina

    2013-01-01

    We present a case report of a 27 years old pacient with central retinal vein occlussion and macular edema. The pacient has a significant reduction of the macular aedema with complete recovery of vision after the treatment.

  20. 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.

  1. Renal Vein Injury During Percutaneous Nephrolithotomy Procedure

    PubMed Central

    Toffeq, Hewa Mahmood

    2016-01-01

    Abstract Background: Percutaneous nephrostolithotomy is an important approach for removing kidney stones. Puncturing and dilatation are two mandatory steps in percutaneous nephrolithotomy (PCNL). Uncommonly, during dilatation, the dilators can cause direct injury to the main renal vein or to their tributaries. Case Presentation: A 75-year-old female underwent PCNL for partial staghorn stone in the left kidney. During puncturing and dilatation, renal vein tributary was injured, and the nephroscope entered the renal vein and inferior vena cava, which was clearly recognized. Injection of contrast material through the nephroscope confirms the false pathway to the great veins (renal vein and inferior vena cava). Bleeding was controlled intraoperatively by applying Amplatz sheath over the abnormal tract, the procedure was continued and stones were removed. At the end of the procedure, a Foley catheter was used as a nephrostomy tube and its balloon was inflated inside the renal pelvis and pulled back with light pressure to the lower calix, which was the site of injury to the renal vein tributaries, then the nephrostomy tube was closed; by this we effectively controlled the bleeding. The patient remained hemodynamically stable; antegrade pyelography was done on the second postoperative day, there was distally patent ureter with no extravasation, neither contrast leak to renal vein, and was discharged home at third postoperative day. After 2 weeks, the nephrostomy tube was gradually removed in the operative room, without bleeding, on the next day, Double-J stent was removed. Conclusion: Direct injury and false tract to the renal vein tributaries during PCNL can result in massive hemorrhage, and can be treated conservatively in hemodynamically stable patients, using a nephrostomy catheter as a tamponade. PMID:27704054

  2. Isolated inferior mesenteric portal hypertension with giant inferior mesenteric vein and anomalous inferior mesenteric vein insertion

    PubMed Central

    Prasad, G. Raghavendra; Billa, Srikar; Bhandari, Pavaneel; Hussain, Aijaz

    2013-01-01

    Extrahepatic portal hypertension is not an uncommon disease in childhood, but isolated inferior mesenteric portal varices and lower gastrointestinal (GI) bleed have not been reported till date. A 4-year-old girl presented with lower GI bleed. Surgical exploration revealed extrahepatic portal vein obstruction with giant inferior mesenteric vein and colonic varices. Inferior mesenteric vein was joining the superior mesenteric vein. The child was treated successfully with inferior mesenteric – inferior vena caval anastomosis. The child was relieved of GI bleed during the follow-up. PMID:23798814

  3. Improvements of deep vein reflux following radiofrequency ablation for saphenous vein incompetence.

    PubMed

    Kim, Suh Min; Jung, In Mok; Chung, Jung Kee

    2017-02-01

    Objectives The aim of this study was to describe the changes of deep vein reflux after radiofrequency ablation for great saphenous vein incompetence. Method The data on 139 limbs which were treated with radiofrequency ablation for great saphenous vein incompetence were prospectively collected and reviewed. Results Deep vein reflux was present in 43 of 139 limbs (30.9%). There were no significant differences in the rate of successful closure, the incidence of procedure-related complications, and the improvements of symptoms and quality of life between the limbs with or without deep vein reflux. With a mean follow-up of 5.9 months, the peak reflux velocity and duration of reflux were improved in all limbs with deep vein reflux and it was completely corrected in 13 limbs (30.2%) after radiofrequency ablation. Conclusions The presence of deep vein reflux does not affect the treatment outcomes of radiofrequency ablation for great saphenous vein incompetence and is improved in all patients. Deep vein reflux is not a barrier to performing radiofrequency ablation.

  4. Wind Streaks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 12 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth.

    Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms.

    Windstreaks are features caused by the interaction of wind and topographic landforms. The raised rims and bowls of impact craters causes a complex interaction such that the wind vortex in the lee of the crater can both scour away the surface dust and deposit it back in the center of the lee. If you look closely, you will see evidence of this in a darker 'rim' enclosing a brighter interior.

    Image information: VIS instrument. Latitude 6.9, Longitude 69.4 East (290.6 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 California Institute of Technology in Pasadena.

  5. 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.

  6. Subclavian vein thrombosis: A continuing challenge

    SciTech Connect

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

    1990-07-01

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

  7. Experimental therapies for yellow fever

    PubMed Central

    Julander, Justin G.

    2013-01-01

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

  8. Fine structures of embryonic discs of in vivo post-hatching porcine blastocysts at the pre-primitive streak stage.

    PubMed

    Xia, P; Liu, Z; Qin, P

    2011-04-01

    To date, reports about the ultrastructure of porcine embryonic discs have not shown details of the primitive streak. The main objective of this study was to examine the ultrastructure of interior and exterior embryonic discs in porcine in vivo blastocysts with diameters of 1, 3 and 9 mm using scanning electron microscopy and transmission electron microscopy. For the first time, we revealed the ultrastructure of the unusual group of cells in the pre-primitive streak area of embryonic discs. The cells were 1-2 μm in diameter, had high electron density and contained abundant, free ribosomes and endoplasmic reticulum. These primitive streak cells could represent original embryonic stem cells or represent a stem cell niche. The results also showed three types of cells on the exterior surface of the embryonic discs. Moreover, our results provided morphological evidence of condensed nuclei in the smooth cells on the surface of the embryonic disc.

  9. Frequency-Domain Streak Camera and Tomography for Ultrafast Imaging of Evolving and Channeled Plasma Accelerator Structures

    SciTech Connect

    Li Zhengyan; Zgadzaj, Rafal; Wang Xiaoming; Reed, Stephen; Dong Peng; Downer, Michael C.

    2010-11-04

    We demonstrate a prototype Frequency Domain Streak Camera (FDSC) that can capture the picosecond time evolution of the plasma accelerator structure in a single shot. In our prototype Frequency-Domain Streak Camera, a probe pulse propagates obliquely to a sub-picosecond pump pulse that creates an evolving nonlinear index 'bubble' in fused silica glass, supplementing a conventional Frequency Domain Holographic (FDH) probe-reference pair that co-propagates with the 'bubble'. Frequency Domain Tomography (FDT) generalizes Frequency-Domain Streak Camera by probing the 'bubble' from multiple angles and reconstructing its morphology and evolution using algorithms similar to those used in medical CAT scans. Multiplexing methods (Temporal Multiplexing and Angular Multiplexing) improve data storage and processing capability, demonstrating a compact Frequency Domain Tomography system with a single spectrometer.

  10. Picosecond-resolved X-ray absorption spectroscopy at low signal contrast using a hard X-ray streak camera

    SciTech Connect

    Adams, Bernhard W.; Rose-Petruck, Christoph; Jiao, Yishuo

    2015-06-24

    A picosecond-resolving hard-X-ray streak camera has been in operation for several years at Sector 7 of the Advanced Photon Source (APS). Several upgrades have been implemented over the past few years to optimize integration into the beamline, reduce the timing jitter, and improve the signal-to-noise ratio. These include the development of X-ray optics for focusing the X-rays into the sample and the entrance slit of the streak camera, and measures to minimize the amount of laser light needed to generate the deflection-voltage ramp. For the latter, the photoconductive switch generating the deflection ramp was replaced with microwave power electronics. With these, the streak camera operates routinely at 88 MHz repetition rate, thus making it compatible with all of the APS fill patterns including use of all the X-rays in the 324-bunch mode. Sample data are shown to demonstrate the performance.

  11. Frequency-Domain Streak Camera and Tomography for Ultrafast Imaging of Evolving and Channeled Plasma Accelerator Structures

    NASA Astrophysics Data System (ADS)

    Li, Zhengyan; Zgadzaj, Rafal; Wang, Xiaoming; Reed, Stephen; Dong, Peng; Downer, Michael C.

    2010-11-01

    We demonstrate a prototype Frequency Domain Streak Camera (FDSC) that can capture the picosecond time evolution of the plasma accelerator structure in a single shot. In our prototype Frequency-Domain Streak Camera, a probe pulse propagates obliquely to a sub-picosecond pump pulse that creates an evolving nonlinear index "bubble" in fused silica glass, supplementing a conventional Frequency Domain Holographic (FDH) probe-reference pair that co-propagates with the "bubble". Frequency Domain Tomography (FDT) generalizes Frequency-Domain Streak Camera by probing the "bubble" from multiple angles and reconstructing its morphology and evolution using algorithms similar to those used in medical CAT scans. Multiplexing methods (Temporal Multiplexing and Angular Multiplexing) improve data storage and processing capability, demonstrating a compact Frequency Domain Tomography system with a single spectrometer.

  12. Sinogram-based coil selection for streak artifact reduction in undersampled radial real-time magnetic resonance imaging

    PubMed Central

    Frahm, Jens

    2016-01-01

    Background Streak artifacts are a common problem in radial magnetic resonance imaging (MRI). We therefore developed a method for automatically excluding receiver coil elements which lead to these artifacts. Methods The proposed coil selection relates to real-time MRI data based on highly undersampled radial acquisitions. It exploits differences between high- and low-resolution sinograms reconstructed from datasets acquired during preparatory scans. Apart from phantom validations, the performance was assessed for real-time MRI studies of different human organ systems in vivo. Results The algorithm greatly reduces streak artifact strength without compromising image quality in other parts of the image. It is robust with respect to different experimental settings and fast to be included in the online reconstruction pipeline for real-time MRI. Conclusions The proposed method enables a fast reduction of streak artifacts in radial real-time MRI. PMID:27942475

  13. 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.

  14. The Allantoic Core Domain: New Insights Into Development of the Murine Allantois and Its Relation to the Primitive Streak

    PubMed Central

    Downs, Karen M.; Inman, Kimberly E.; Jin, Dexter X.; Enders, Allen C.

    2010-01-01

    The whereabouts and properties of the posterior end of the primitive streak have not been identified in any species. In the mouse, the streak’s posterior terminus is assumed to be confined to the embryonic compartment, and to give rise to the allantois, which links the embryo to its mother during pregnancy. In this study, we have refined our understanding of the biology of the murine posterior primitive streak and its relation to the allantois. Through a combination of immunostaining and morphology, we demonstrate that the primitive streak spans the posterior extraembryonic and embryonic regions at the onset of the neural plate stage (~7.0 days postcoitum, dpc). Several hours later, the allantoic bud emerges from the extraembryonic component of the primitive streak (XPS). Then, possibly in collaboration with overlying allantois-associated extraembryonic visceral endoderm, the XPS establishes a germinal center within the allantois, named here the Allantoic Core Domain (ACD). Microsurgical removal of the ACD beyond headfold (HF) stages resulted in the formation of allantoic regenerates that lacked the ACD and failed to elongate; nevertheless, vasculogenesis and vascular patterning proceeded. In situ and transplantation fate mapping demonstrated that, from HF stages onward, the ACD’s progenitor pool contributed to the allantois exclusive of the proximal flanks. By contrast, the posterior intraembryonic primitive streak (IPS) provided the flanks. Grafting the ACD into TC/TC hosts, whose allantoises are significantly foreshortened, restored allantoic elongation. These results revealed that the ACD is essential for allantoic elongation, but the cues required for vascularization lie outside of it. On the basis of these and previous findings, we conclude that the posterior primitive streak of the mouse conceptus is far more complex than was previously believed. Our results provide new directives for addressing the origin and development of the umbilical cord, and

  15. Small Near-Earth Asteroids in the Palomar Transient Factory Survey: A Real-Time Streak-detection System

    NASA Astrophysics Data System (ADS)

    Waszczak, Adam; Prince, Thomas A.; Laher, Russ; Masci, Frank; Bue, Brian; Rebbapragada, Umaa; Barlow, Tom; Surace, Jason; Helou, George; Kulkarni, Shrinivas

    2017-03-01

    Near-Earth asteroids (NEAs) in the 1–100 meter size range are estimated to be ∼1,000 times more numerous than the ∼15,000 currently cataloged NEAs, most of which are in the 0.5–10 kilometer size range. Impacts from 10–100 meter size NEAs are not statistically life-threatening, but may cause significant regional damage, while 1–10 meter size NEAs with low velocities relative to Earth are compelling targets for space missions. We describe the implementation and initial results of a real-time NEA-discovery system specialized for the detection of small, high angular rate (visually streaked) NEAs in Palomar Transient Factory (PTF) images. PTF is a 1.2-m aperture, 7.3 deg2 field of view (FOV) optical survey designed primarily for the discovery of extragalactic transients (e.g., supernovae) in 60-second exposures reaching ∼20.5 visual magnitude. Our real-time NEA discovery pipeline uses a machine-learned classifier to filter a large number of false-positive streak detections, permitting a human scanner to efficiently and remotely identify real asteroid streaks during the night. Upon recognition of a streaked NEA detection (typically within an hour of the discovery exposure), the scanner triggers follow-up with the same telescope and posts the observations to the Minor Planet Center for worldwide confirmation. We describe our 11 initial confirmed discoveries, all small NEAs that passed 0.3–15 lunar distances from Earth. Lastly, we derive useful scaling laws for comparing streaked-NEA-detection capabilities of different surveys as a function of their hardware and survey-pattern characteristics. This work most directly informs estimates of the streak-detection capabilities of the Zwicky Transient Facility (ZTF, planned to succeed PTF in 2017), which will apply PTF’s current resolution and sensitivity over a 47-deg2 FOV.

  16. Depth resolution improvement of streak tube imaging lidar using optimal signal width

    NASA Astrophysics Data System (ADS)

    Ye, Guangchao; Fan, Rongwei; Lu, Wei; Dong, Zhiwei; Li, Xudong; He, Ping; Chen, Deying

    2016-10-01

    Streak tube imaging lidar (STIL) is an active imaging system that has a high depth resolution with the use of a pulsed laser transmitter and streak tube receiver to produce three-dimensional (3-D) range images. This work investigates the optimal signal width of the lidar system, which is helpful to improve the depth resolution based on the centroid algorithm. Theoretical analysis indicates that the signal width has a significant effect on the depth resolution and the optimal signal width can be determined for a given STIL system, which is verified by both the simulation and experimental results. An indoor experiment with a planar target was carried out to validate the relation that the range error decreases first and then increases with the signal width, resulting in an optimal signal width of 8.6 pixels. Finer 3-D range images of a cartoon model were acquired by using the optimal signal width and a minimum range error of 5.5 mm was achieved in a daylight environment.

  17. Identification of rice black-streaked dwarf fijivirus in maize with rough dwarf disease in China.

    PubMed

    Fang, S; Yu, J; Feng, J; Han, C; Li, D; Liu, Y

    2001-01-01

    Three virus isolates from maize with rough dwarf in different provinces in China were analyzed at the molecular level. When compared to an isolate from diseased rice plants in Hubei Province, all four isolates had identical genomic RNA electrophoretic profiles, which were composed of ten double-stranded (ds) RNAs. Full-length cDNAs of segment 10 (S10) from each of the four isolates were cloned by RT-PCR and the complete sequences were determined. Analysis of the sequences revealed that each consisted of 1801 nucleotides and contained a single open reading frame (ORF) which potentially encoded a protein with 558 amino acids. Further, the sequences showed more than 97.0% and 98.0% identity at nucleotide and amino acid levels, respectively. In addition, their identities to rice black-streaked dwarf virus S10 were significantly higher than those to maize rough dwarf virus S10. Based on these results, it is suggested that the virus which causes this maize disease in China is rice black-streaked dwarf virus.

  18. Streak Tectonics associated with the Irregular Slab Topography at Subduction Zones

    NASA Astrophysics Data System (ADS)

    Eguchi, T.

    2015-12-01

    We demonstrate the physical features of streak tectonics (or abrasion tectonics) associated with the irregular surface topography, such as local convex rise or seamount(s), on the downgoing slab at subduction zones. Marine surveys such as sophisticated multichannel seismic experiments have revealed the detailed vertical structure of the overriding lithosphere as well as the upper-most part of downgoing slab at the fore-arc zone from the trench axis through the inclined plate interface zone at a depth of 10 - 15km. As previously, some researchers (e.g., Eguchi, 1979, 1996; Hilde, 1983; Suzan, 2010) demonstrated the influence of the surface irregular topography of the slab on the occurrence regime of greater interplate seismic events with the low-angle underthrusting slip. However, the earlier studies didn't incorporate any effects due to the spherical buckling of oceanic lithosphere with the age-dependent elastic thickness at subduction zones. In the case of a subduction zone where the slab age has gradually been decreasing or increasing, the spherical buckling of elastic shell (e.g., Eguchi, 2012) suggests that the interplate mechanical coupling strength varies with time and space. Next, we argue some tectonic features of strain-rate dependent deformation at areas surrounding an isolated-seamount on the downgoing slab, such as the quasi-static fluid lubrication, boundary lubrication or plastic deformation. We then discuss how to represent mathematically the streak process during a larger interplate seismic event at the non-uniform plate interface zone.

  19. Direct evidence for encoding of motion streaks in human visual cortex

    PubMed Central

    Apthorp, Deborah; Schwarzkopf, D. Samuel; Kaul, Christian; Bahrami, Bahador; Alais, David; Rees, Geraint

    2013-01-01

    Temporal integration in the visual system causes fast-moving objects to generate static, oriented traces (‘motion streaks’), which could be used to help judge direction of motion. While human psychophysics and single-unit studies in non-human primates are consistent with this hypothesis, direct neural evidence from the human cortex is still lacking. First, we provide psychophysical evidence that faster and slower motions are processed by distinct neural mechanisms: faster motion raised human perceptual thresholds for static orientations parallel to the direction of motion, whereas slower motion raised thresholds for orthogonal orientations. We then used functional magnetic resonance imaging to measure brain activity while human observers viewed either fast (‘streaky’) or slow random dot stimuli moving in different directions, or corresponding static-oriented stimuli. We found that local spatial patterns of brain activity in early retinotopic visual cortex reliably distinguished between static orientations. Critically, a multivariate pattern classifier trained on brain activity evoked by these static stimuli could then successfully distinguish the direction of fast (‘streaky’) but not slow motion. Thus, signals encoding static-oriented streak information are present in human early visual cortex when viewing fast motion. These experiments show that motion streaks are present in the human visual system for faster motion. PMID:23222445

  20. Synchroscan streak camera imaging at a 15-MeV photoinjector with emittance exchange

    NASA Astrophysics Data System (ADS)

    Lumpkin, A. H.; Ruan, J.; Thurman-Keup, R.

    2012-09-01

    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 fast single-sweep module of the Hamamatsu C5680 streak camera with an intrinsic shot-to-shot trigger jitter of 10-20 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 ˜1 ps over 10 s of minutes. These steps allowed us to measure both the UV laser pulse train at 263 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 0.25-1 nC per micropulse. The phase-locked delay box allowed us to assess chromatic temporal effects and instigated another upgrade to an all-mirror input optics barrel. In addition, we added a slow sweep horizontal deflection plug-in unit to provide dual-sweep capability for the streak camera. We report on a series of measurements made during the commissioning of these upgrades including bunch-length and phase effects using the emittance exchange beamline and simultaneous imaging of a UV drive laser component, OTR, and the 800 nm diagnostics laser.

  1. Slit-mounted LED fiducial system for rotating mirror streak cameras

    SciTech Connect

    Shaw, L.L.; Muelder, S.A.; Rivera, A.T.

    1991-01-01

    We have developed a fiducial system for rotating mirror streak cameras that utilizes light emitting diodes mounted at the slit position of the camera. The diodes are driven to the required high brightness by a unique pulse power circuit designed to provide high voltage, high current pulses 18 nanoseconds in length at a frequency of up to 2.5 megahertz. The availability of super bright light emitting diodes with a wavelength of 630 to 640 nanometers allows us to record fiducial pulses, at streaking speeds in excess of 20mm per microsecond, on all the black and white films commonly used in high speed photography. The time marks on the film record are referenced to the real time of the experiment from a clock-driver that controls the start and frequency of the fiducial pulse train and by three adjustable and discreet blanked fiducials. This paper discusses the development of this system and describes the full setup as used at LLNL. 6 refs., 4 figs.

  2. Absolute calibration of the OMEGA streaked optical pyrometer for temperature measurements of compressed materials

    DOE PAGES

    Gregor, M. C.; Boni, R.; Sorce, A.; ...

    2016-11-29

    Experiments in high-energy-density physics often use optical pyrometry to determine temperatures of dynamically compressed materials. In combination with simultaneous shock-velocity and optical-reflectivity measurements using velocity interferometry, these experiments provide accurate equation-of-state data at extreme pressures (P > 1 Mbar) and temperatures (T > 0.5 eV). This paper reports on the absolute calibration of the streaked optical pyrometer (SOP) at the Omega Laser Facility. The wavelength-dependent system response was determined by measuring the optical emission from a National Institute of Standards and Technology–traceable tungsten-filament lamp through various narrowband (40 nm-wide) filters. The integrated signal over the SOP’s ~250-nm operating range ismore » then related to that of a blackbody radiator using the calibrated response. We present a simple closed-form equation for the brightness temperature as a function of streak-camera signal derived from this calibration. As a result, error estimates indicate that brightness temperature can be inferred to a precision of <5%.« less

  3. Absolute calibration of the OMEGA streaked optical pyrometer for temperature measurements of compressed materials

    NASA Astrophysics Data System (ADS)

    Gregor, M. C.; Boni, R.; Sorce, A.; Kendrick, J.; McCoy, C. A.; Polsin, D. N.; Boehly, T. R.; Celliers, P. M.; Collins, G. W.; Fratanduono, D. E.; Eggert, J. H.; Millot, M.

    2016-11-01

    Experiments in high-energy-density physics often use optical pyrometry to determine temperatures of dynamically compressed materials. In combination with simultaneous shock-velocity and optical-reflectivity measurements using velocity interferometry, these experiments provide accurate equation-of-state data at extreme pressures (P > 1 Mbar) and temperatures (T > 0.5 eV). This paper reports on the absolute calibration of the streaked optical pyrometer (SOP) at the Omega Laser Facility. The wavelength-dependent system response was determined by measuring the optical emission from a National Institute of Standards and Technology-traceable tungsten-filament lamp through various narrowband (40-nm-wide) filters. The integrated signal over the SOP's ˜250-nm operating range is then related to that of a blackbody radiator using the calibrated response. We present a simple closed-form equation for the brightness temperature as a function of streak-camera signal derived from this calibration. Error estimates indicate that brightness temperature can be inferred to a precision of <5%.

  4. Absolute calibration of the OMEGA streaked optical pyrometer for temperature measurements of compressed materials

    SciTech Connect

    Gregor, M. C.; Boni, R.; Sorce, A.; Kendrick, J.; McCoy, C. A.; Polsin, D. N.; Boehly, T. R.; Celliers, P. M.; Collins, G. W.; Fratanduono, D. E.; Eggert, J. H.; Millot, M.

    2016-11-29

    Experiments in high-energy-density physics often use optical pyrometry to determine temperatures of dynamically compressed materials. In combination with simultaneous shock-velocity and optical-reflectivity measurements using velocity interferometry, these experiments provide accurate equation-of-state data at extreme pressures (P > 1 Mbar) and temperatures (T > 0.5 eV). This paper reports on the absolute calibration of the streaked optical pyrometer (SOP) at the Omega Laser Facility. The wavelength-dependent system response was determined by measuring the optical emission from a National Institute of Standards and Technology–traceable tungsten-filament lamp through various narrowband (40 nm-wide) filters. The integrated signal over the SOP’s ~250-nm operating range is then related to that of a blackbody radiator using the calibrated response. We present a simple closed-form equation for the brightness temperature as a function of streak-camera signal derived from this calibration. As a result, error estimates indicate that brightness temperature can be inferred to a precision of <5%.

  5. PS-1/S1 picosecond streak camera application for multichannel laser system diagnostics

    SciTech Connect

    Garanin, S G; Bel'kov, S A; Rogozhnikov, G S; Rukavishnikov, N N; Romanov, V V; Voronich, I N; Vorob'ev, N S; Gornostaev, P B; Lozovoi, V I; Shchelev, M Ya

    2014-08-31

    A PS-1/S1 picosecond image-tube streak camera (ITSC) with slit scan (streak camera), developed and manufactured at the General Physics Institute RAS, has been used to measure the spatiotemporal characteristics of ultrashort laser pulses generated by a petawatt-power laser installation 'FEMTO' at the Institute of Laser Physics Research in Sarov. It is found that such a camera is suitable for measuring the spatial and temporal parameters of single laser pulses with an accuracy of about one picosecond. It is shown that the intensity time profile of a train of picosecond pulses may be precisely defined for the pulses separated in time by a few picoseconds. The camera allows the contrast of radiation to be determined with a high (no less than 10{sup 3}) accuracy; spatial distribution of the laser pulses can be measured with an accuracy of tens of microns, and the temporal separation of single laser pulses can be identified with an accuracy of 1 – 1.5 ps. (extreme light fields and their applications)

  6. Nonlinear response of the photocathode of an x-ray streak camera to UV light

    SciTech Connect

    Kyrala, G.A.; Oro, D.M.; Studebaker, J.K.; Wood, W.M.; Schappert, G.T.; Watts, S.; Fulton, R.D.

    1994-09-01

    We have found that a potassium-iodide photocathode of an x-ray streak camera responds to UV light at {lambda}=308 nm. The photocathode surface work function, 6.5 eV, is larger than the 4 eV energy of the UV photon, hence the source of the response is interesting. We will present results on the response of a transmission type potassium-iodide photocathode to the UV light from a {lambda}308 nm, subpicosecond XeCl laser and from a {lambda}=326 nm HeCd laser. We will test for the nonlinearity of the yield to measure of the number of photons that are needed to be absorbed before a signal is recorded. We will present data on the effect of the UV irradiance on the yield, as well as on the temporal width of the recorded signal. We will give an explanation of the observation and its effect on the dynamic-range response of the streak-camera. We will show that the response is linear with the incident irradiance, up to an incident irradiance of 10{sup 8} W/cm{sup 2} and we will explain the observation.

  7. Immunodiagnosis of episomal Banana streak MY virus using polyclonal antibodies to an expressed putative coat protein.

    PubMed

    Sharma, Susheel Kumar; Kumar, P Vignesh; Baranwal, Virendra Kumar

    2014-10-01

    A cryptic Badnavirus species complex, known as banana streak viruses (BSV) poses a serious threat to banana production and genetic improvement worldwide. Due to the presence of integrated BSV sequences in the banana genome, routine detection is largely based on serological and nucleo-serological diagnostic methods which require high titre specific polyclonal antiserum. Viral structural proteins like coat protein (CP) are the best target for in vitro expression, to be used as antigen for antiserum production. However, in badnaviruses precise CP sequences are not known. In this study, two putative CP coding regions (p48 and p37) of Banana streak MY virus (BSMYV) were identified in silico by comparison with caulimoviruses, retroviruses and Rice tungro bacilliform virus. The putative CP coding region (p37) was in vitro expressed in pMAL system and affinity purified. The purified fusion protein was used as antigen for raising polyclonal antiserum in rabbit. The specificity of antiserum was confirmed in Western blots, immunosorbent electron microscopy (ISEM) and antigen coated plate-enzyme linked immunosorbent assay (ACP-ELISA). The antiserum (1:2000) was successfully used in ACP-ELISA for specific detection of BSMYV infection in field and tissue culture raised banana plants. The antiserum was also utilized in immuno-capture PCR (IC-PCR) based indexing of episomal BSMYV infection. This is the first report of in silico identification of putative CP region of BSMYV, production of polyclonal antiserum against recombinant p37 and its successful use in immunodetection.

  8. An Optical Streak Diagnostic for Observing Anode-Cathode Plasmas for Radiographic Source Development

    SciTech Connect

    Droemer, Darryl W.; Crain, Marlon D.; Lare, Gregory A.; Bennett, Nichelle L.; Johnston, Mark D.

    2013-06-13

    National Security Technologies, LLC, and Sandia National Laboratories are collaborating in the development of pulsed power–driven flash x-ray radiographic sources that utilize high-intensity electron beam diodes. The RITS 6 (Radiographic Integrated Test Stand) accelerator at Sandia is used to drive a self magnetic pinch diode to produce a Bremsstrahlung x-ray source. The high electric fields and current densities associated with these short A-K gap pinch beam diodes present many challenges in diode development. Plasmas generated at both the anode and cathode affect the diode performance, which is manifested in varying spot (source) sizes, total dose output, and impedance profiles. Understanding the nature of these plasmas including closure rates and densities is important in modeling their behavior and providing insight into their mitigation. In this paper we describe a streak camera–based optical diagnostic that is capable of observing and measuring plasma evolution within the A-K gap. By imaging a region of interest onto the input slit of a streak camera, we are able to produce a time-resolved one-dimensional image of the evolving plasma. Typical data are presented.

  9. An effective preprocessing method for finger vein recognition

    NASA Astrophysics Data System (ADS)

    Peng, JiaLiang; Li, Qiong; Wang, Ning; Abd El-Latif, Ahmed A.; Niu, Xiamu

    2013-07-01

    The image preprocessing plays an important role in finger vein recognition system. However, previous preprocessing schemes remind weakness to be resolved for the high finger vein recongtion performance. In this paper, we propose a new finger vein preprocessing that includes finger region localization, alignment, finger vein ROI segmentation and enhancement. The experimental results show that the proposed scheme is capable of enhancing the quality of finger vein image effectively and reliably.

  10. 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.

  11. Hippocrates, cardiology, Confucius and the Yellow Emperor.

    PubMed

    Cheng, T O

    2001-12-01

    Although Hippocrates (460-c.375 BC) has been traditionally recognized as the Father of Medicine, the fact that he was seminal in the development of cardiology is much less well known. Evidence is presented to support the notion that Hippocrates could also be considered the Father of Cardiology. Hippocrates also had many of the teachings and practices in common with Confucius (c.551-c.479 BC) and the Yellow Emperor of China (2695-2589 BC). Whereas Confucius was not a physician, the Yellow Emperor was an ancient Chinese physician whose Huang Di Neijing, the Yellow Emperor's Canon of Internal Medicine, is the oldest known treatise of medicine in existence.

  12. Clara Maass, yellow fever and human experimentation.

    PubMed

    Chaves-Carballo, Enrique

    2013-05-01

    Clara Louise Maass, a 25-year-old American nurse, died of yellow fever on August 24, 1901, following experimental inoculation by infected mosquitoes in Havana, Cuba. The human yellow fever experiments were initially conducted by MAJ Walter Reed, who first used written informed consent and proved the validity of Finlay's mosquito-vector hypothesis. Despite informed consent form and an incentive of $100 in U.S. gold, human subjects were exposed to a deadly virus. The deaths of Clara Maass and two Spanish immigrants resulted in a public outcry and the immediate cessation of yellow fever human experiments in Cuba.

  13. Adventitial cystic disease of the common femoral vein presenting as deep vein thrombosis.

    PubMed

    Kim, Young-Kyun; Chun, Ho Jong; Hwang, Jeong Kye; Kim, Ji Il; Kim, Sang Dong; Park, Sun-Cheol; Moon, In Sung

    2016-07-01

    Adventitial cystic disease of the common femoral vein is a rare condition. We herein report the case of a 50-year-old woman who presented with painless swelling in her left lower leg that resembled deep vein thrombosis. She underwent femoral exploration and excision of the cystic wall. The presentation, investigation, treatment, and pathology of this condition are discussed with a literature review.

  14. 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. PMID:27418788

  15. 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

  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, 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...

  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, 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. Portal vein aneurysm: What to know.

    PubMed

    Laurenzi, Andrea; Ettorre, Giuseppe Maria; Lionetti, Raffaella; Meniconi, Roberto Luca; Colasanti, Marco; Vennarecci, Giovanni

    2015-11-01

    Portal vein aneurysm is an unusual vascular dilatation of the portal vein, which was first described by Barzilai and Kleckner in 1956 and since then less than 200 cases have been reported. The aim of this article is to provide an overview of the international literature to better clarify various aspects of this rare nosological entity and provide clear evidence-based summary, when available, of the clinical and surgical management. A systematic literature search of the Pubmed database was performed for all articles related to portal vein aneurysm. All articles published from 1956 to 2014 were examined for a total of 96 reports, including 190 patients. Portal vein aneurysm is defined as a portal vein diameter exceeding 1.9 cm in cirrhotic patients and 1.5 cm in normal livers. It can be congenital or acquired and portal hypertension represents the main cause of the acquired version. Surgical indication is considered in case of rupture, thrombosis or symptomatic aneurysms. Aneurysmectomy and aneurysmorrhaphy are considered in patients with normal liver, while shunt procedures or liver transplantation are the treatment of choice in case of portal hypertension. Being such a rare vascular entity its management should be reserved to high-volume tertiary hepato-biliary centres.

  12. Robotic Assisted Cannulation of Occluded Retinal Veins

    PubMed Central

    Meenink, Thijs C. M.; Janssens, Tom; Vanheukelom, Valerie; Naus, Gerrit J. L.; Beelen, Maarten J.; Meers, Caroline; Jonckx, Bart; Stassen, Jean-Marie

    2016-01-01

    Purpose To develop a methodology for cannulating porcine retinal venules using a robotic assistive arm after inducing a retinal vein occlusion using the photosensitizer rose bengal. Methodology Retinal vein occlusions proximal to the first vascular branch point were induced following intravenous injection of rose bengal by exposure to 532nm laser light delivered by slit-lamp or endolaser probe. Retinal veins were cannulated by positioning a glass catheter tip using a robotically controlled micromanipulator above venules with an outer diameter of 80μm or more and performing a preset piercing maneuver, controlled robotically. The ability of a balanced salt (BSS) solution to remove an occlusion by repeat distention of the retinal vein was also assessed. Results Cannulation using the preset piercing program was successful in 9 of 9 eyes. Piercing using the micromanipulator under manual control was successful in only 24 of 52 attempts, with several attempts leading to double piercing. The best location for cannulation was directly proximal to the occlusion. Infusion of BSS did not result in the resolution of the occlusion. Conclusion Cannulation of venules using a robotic microassistive arm can be achieved with consistency, provided the piercing is robotically driven. The model appears robust enough to allow testing of therapeutic strategies aimed at eliminating a retinal vein thrombus and its evolution over time. PMID:27676261

  13. A new approach for sclera vein recognition

    NASA Astrophysics Data System (ADS)

    Thomas, N. L.; Du, Yingzi; Zhou, Zhi

    2010-04-01

    The vein structure in the sclera is stable over time, unique to each person, and well suited for human identification. A few researchers have performed sclera vein pattern recognition and reported promising initial results. Sclera recognition poses several challenges: the vein structure moves and deforms with the movement of the eye; images of sclera patterns are often defocused and/or saturated; and, most importantly, the vein structure in the sclera is multi-layered and has complex non-linear deformation. In this paper, we proposed a new method for sclera recognition: First, we developed a color-based sclera region estimation scheme for sclera segmentation. Second, we designed a Gabor wavelet-based sclera pattern enhancement method, and an adaptive thresholding method to emphasize and binarize the sclera vein patterns. Third, we proposed a line descriptor-based feature extraction, registration, and matching method that is illumination-, scale-, orientation-, and deformation-invariant, and can mitigate the multi-layered deformation effects exhibited in the sclera and tolerate segmentation error. It is empirically verified using the UBIRIS database that the proposed method can perform accurate sclera recognition.

  14. Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

    PubMed Central

    Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B.

    2014-01-01

    62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. Conclusion The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival. PMID:25568802

  15. GPU-accelerated Faint Streak Detection for Uncued Surveillance of LEO

    NASA Astrophysics Data System (ADS)

    Zimmer, P.; Ackermann, M.; McGraw, J. T.

    2013-09-01

    By astronomical standards, small objects (<10cm) in LEO illuminated by the Sun under terminator conditions are quite bright, depositing 100's to 1000's of photons per second into small telescope apertures (< 1m diameter). The challenge in discovering these objects with no a priori knowledge of their orbit (i.e. uncued surveillance) is that their relative motion with respect to a ground-based telescope makes them appear to have large angular rates of motion, up to and exceeding 1 degree per second. Thus in even a short exposure, the signal from the object is smeared out in a streak with low signal-to-noise per pixel. Go Green Termite (GGT), Inc. of Gilroy, CA, in collaboration with the University of New Mexico (UNM), is building two proof-of-concept wide-field imaging systems to test, develop and prove a novel streak detection technique. The imaging systems are built from off-the-shelf optics and detectors resulting in a 350mm aperture and a 6 square degree field of view. For streak detection, field of view is of critical importance because the maximum exposure time on the object is limited by its crossing time. In this way, wider fields of view impact surveys for LEO objects both by increasing the survey volume and increasing sensitivity. Using our newly GPU-accelerated detection scheme, the proof-of-concept systems are expected to be able to detect objects fainter than 12th magnitude moving at 1 degree per second and possibly as faint as 13th magnitude for slower moving objects. Meter-class optical systems using these techniques should be able to detect objects fainter than 14th magnitude, which is roughly equivalent to a golf ball at 1000km altitude. The goal of this work is to demonstrate a scalable system for near real time detection of fast moving objects that can be then handed off to other instruments capable of tracking and characterizing them. The two proof-of-concept systems, separated by ~30km, work together by taking simultaneous images of the same

  16. Analysis of Dark Slope Streaks on Mars based on Multitemporal HRSC Data

    NASA Astrophysics Data System (ADS)

    Schreiner, Björn; van Gasselt, Stephan; Jan-Peter, Muller

    2016-04-01

    Recurring slope lineae (RSL) on Mars are dark and narrow downhill oriented surface features found in equatorial regions (1) associated with water or hydrated salt flows (2). On the other hand there are Dark Slope Streaks which seem to be dry avalanches on dust covered slopes (3). The origin of both ist still under discussion. We found linear features in eastern Noctis Labyrinthus region (6°S, 265°E) with lengths of up to several kilometres and lateral extensions of 20-30 metres. As described by (4), RSL fade and recur in the same location over multiple Mars years. Similarily, Dark Slope Streaks form on at least annual to decade-long timescales (5). During 10 years of HRSC observation time (2005-2015) several linear features in Noctis Labyrinthus changed in visibility. Slope parameters and seasonal illumination conditions are investigated based on a digital elevation model derived from HRSC data. For large datasets a feature identification is presented which involves spatial filtering in conjunction with elevation data analysis. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under iMars grant agreement n° 607379. (1) McEwen, A.S., et al. (2014): Recurring slope lineae in equatorial regions of Mars. Nat. Geosci 7: 53-58. (2) Ojha, L. et al. (2015): Spectral evidence for hydrated salts in recurring slope linear on Mars. Nat. Geosci, DOI:10.1038/NGEO2546. (3) Sullivan, R. et al. (2001). Mass Movement Slope Streaks Imaged by the Mars Orbiter Camera. J. Geophys. Res., 106(E10), 23,607-23,633. (4) McEwen, A.S., et al. (2011): Seasonal Flows on Warm Martian Slopes. Science, Vol. 333, Issue 6043, pp. 740-743. (5) Malin, M.C.; Edgett, K.S. (2001). Mars Global Surveyor Mars Orbiter Camera: Interplanetary cruise through primary mission. J. Geophys. Res., 106(E10), 23,429-23,570.

  17. 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

  18. Lost trust: a yellow fever patient response.

    PubMed

    Runge, John S

    2013-12-13

    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.

  19. A Nonlinear Thin-Wall Model for Vein Buckling.

    PubMed

    Lee, Avione Y; Han, Hai-Chao

    2010-12-01

    Tortuous or twisted veins are often seen in the retina, cerebrum, and legs (varicose veins) of one-third of the aged population, but the underlying mechanisms are poorly understood. While the collapse of veins under external pressure has been well documented, the bent buckling of long vein segments has not been studied. The objectives of this study were to develop a biomechanical model of vein buckling under internal pressure and to predict the critical pressure. Veins were modeled as thin-walled nonlinear elastic tubes with the Fung exponential strain energy function. Our results demonstrated that veins buckle due to high blood pressure or low axial tension. High axial tension stabilized veins under internal pressure. Our buckling model estimated the critical pressure accurately compared to the experimental measurements. The buckling equation provides a useful tool for studying the development of tortuous veins.

  20. Oversized vein grafts develop advanced atherosclerosis in hypercholesterolemic minipigs

    PubMed Central

    2012-01-01

    Background Accelerated atherosclerosis is the main cause of late aortocoronary vein graft failure. We aimed to develop a large animal model for the study of pathogenesis and treatment of vein graft atherosclerosis. Methods An autologous reversed jugular vein graft was inserted end-to-end into the transected common carotid artery of ten hypercholesteroemic minipigs. The vein grafts were investigated 12-14 weeks later with ultrasound and angiograpy in vivo and microscopy post mortem. Results One minipig died during follow up (patent vein graft at autopsy), and one vein graft thrombosed early. In the remaining eight patent vein grafts, the mean (standard deviation) intima-media thickness was 712 μm (276 μm) versus 204 μm (74 μm) in the contralateral control internal jugular veins (P < .01). Advanced atherosclerotic plaques were found in three of four oversized vein grafts (diameter of graft > diameter of artery). No plaques were found in four non-oversized vein grafts (P < .05). Conclusions Our model of jugular vein graft in the common carotid artery of hypercholesterolemic minipigs displayed the components of human vein graft disease, i.e. thrombosis, intimal hyperplasia, and atherosclerosis. Advanced atherosclerosis, the main cause of late failure of human aortocoronary vein grafts was only seen in oversized grafts. This finding suggests that oversized vein grafts may have detrimental effects on patient outcome. PMID:22463679

  1. 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.

  2. Wheat streak mosaic virus-encoded NIa-Pro and coat protein are involved in virus superinfection exclusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cross protection or superinfection exclusion (SE) is defined as the phenomenon whereby initial infection by one virus prevents subsequent infection by closely related viruses. The mechanisms of SE are just beginning to be understood. Wheat streak mosaic virus (WSMV; genus: Tritimovirus; family: Poty...

  3. Prediction of the perceived quality of streak distortions in offset-printing with a psychophysically motivated multi-channel model

    NASA Astrophysics Data System (ADS)

    Gadzicki, Konrad; Zetzsche, Christoph

    2013-08-01

    The evaluation of printing machines poses the problem of how distortions like streaks caused by the machine can be detected and assessed automatically. Although luminance variations in prints can be measured quite precisely, the measured functions bear little relevance for the lightness of streaks and other distortions of prints as perceived by human observers. First, the measurements sometimes indicate changes of luminance in regions which are perceived as homogeneous by humans. Second, the measured strength of a distortion correlates often weakly with its perceived strength, which is influenced by a variety of factors, like the shape of a streak's luminance profile and the distribution of luminance variations in its spatial surround. We have used a model of human perception, based on fundamental neurophysiological and psychophysical properties of the visual system, in order to predict the perceptual strength of streaks (i.e. the distortion as perceived by a human observer) from the measured physical luminance signal. For the evaluation of the model, tests with naive and expert observers have been conducted. The results show that the model yields a good correlation (?) to the assessments of human observers and is thus well suited for use in an automatic evaluation system.

  4. Resistance to wheat streak mosaic virus and Triticum mosaic virus in wheat lines carrying Wsm1 and Wsm3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are important viruses of wheat (Triticum aestivum L.) in the Great Plains of United States. In addition to agronomic practices to prevent damage from these viruses, temperature sensitive resistance genes Wsm1, Wsm2 and Wsm3, have bee...

  5. Environmental factors influencing the development of black leaf streak (Mycosphaerella fijiensis Morelet) on bananas in Puerto Rico.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of environmental factors on the development of black leaf streak (BLS) were studied in Puerto Rico under field conditions. Environmental factors evaluated included temperature, relative humidity, rainfall and solar radiation. Their effect on BLS was determined by recording the youngest...

  6. A four-quadrant sequential streak technique to evaluate Campylobacter selective broths for suppressing background flora in broiler carcass rinses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ecometric technique is a semi-quantitative scoring method used in the quality control of culture media in microbiology laboratories. This technique involves inoculation with defined populations of a specific culture onto solid media via a standardized chronological streaking technique, leading ...

  7. Necrotic streak disease of tomato in Florida caused by a new ilarvirus species related to Tulare apple mosaic virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel ilarvirus for which the name Tomato necrotic streak virus (TomNSV) is proposed was detected in Florida tomato plants beginning in October 2013. Symptoms including necrosis of leaves, petioles and stems, and necrotic rings or spots on fruits were observed. This report provides an overview o...

  8. Genomic and biological characterization of Tomato necrotic streak virus, a novel subgroup 2 ilarvirus infecting tomato in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato necrotic streak virus (TomNSV) is a recently described ilarvirus that was detected in tomato in Florida. The full TomNSV genome sequence revealed it to be a novel subgroup 2 ilarvirus with little nucleotide identity to other previously reported tomato-infecting ilarviruses. Experimental hos...

  9. Development and validation of high-throughput single nucleotide polymorphisms for wheat streak mosaic virus resistance gene Wsm2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) can cause significant yield loss in wheat (Triticum aestivum L.) in the Great Plains of North America. A recently identified WSMV resistance gene, Wsm2, was mapped to chromosome 3BS in germplasm line ‘CO960293–2’. Effective genetic markers tightly linked to the gene ...

  10. Transcriptome of the plant virus vector Graminella nigrifrons, and the molecular interactions of Maize fine streak rhabdovirus transmission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Leafhoppers (Hemiptera:Cicadellidae) are plant-phloem feeders that are known for their ability to vector plant pathogens. The black-faced leafhopper (Graminella nigrifrons) has been identified as the only known vector for the Maize fine streak virus (MFSV), an emerging plant pathogen in...

  11. A 'chemotactic dipole' mechanism for large-scale vortex motion during primitive streak formation in the chick embryo.

    PubMed

    Sandersius, S A; Chuai, M; Weijer, C J; Newman, T J

    2011-08-01

    Primitive streak formation in the chick embryo involves significant coordinated cell movement lateral to the streak, in addition to the posterior-anterior movement of cells in the streak proper. Cells lateral to the streak are observed to undergo 'polonaise movements', i.e. two large counter-rotating vortices, reminiscent of eddies in a fluid. In this paper, we propose a mechanism for these movement patterns which relies on chemotactic signals emitted by a dipolar configuration of cells in the posterior region of the epiblast. The 'chemotactic dipole' consists of adjacent regions of cells emitting chemo-attractants and chemo-repellents. We motivate this idea using a mathematical analogy between chemotaxis and electrostatics, and test this idea using large-scale computer simulations. We implement active cell response to both neighboring mechanical interactions and chemotactic gradients using the Subcellular Element Model. Simulations show the emergence of large-scale vortices of cell movement. The length and time scales of vortex formation are in reasonable agreement with experimental data. We also provide quantitative estimates for the robustness of the chemotaxis dipole mechanism, which indicate that the mechanism has an error tolerance of about 10% to variation in chemotactic parameters, assuming that only 1% of the cell population is involved in emitting signals. This tolerance increases for larger populations of cells emitting signals.

  12. Evaluation of triticale accessions for resistance to wheat bacterial leaf streak caused by Xanthomonas translucens pv. undulosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The bacterium Xanthomonas translucens pv. undulosa (Xtu) causes bacterial leaf streak (BLS) on wheat and other small grains. Several triticale accessions were reported to possess high levels of resistance to wheat Xtu strains. In this study, we evaluated a worldwide collection of 502 triticale acces...

  13. Association mapping of quantitative trait loci responsible for resistance to Bacterial Leaf Streak and Spot Blotch in spring wheat landraces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa, and spot blotch (SB), caused by Cochliobolus sativus are two major diseases of wheat (Triticum aestivum L.). Planting resistant cultivars is the best approach to manage these diseases and identifying new sources of resistan...

  14. Compositions of Low Albedo Intracrater Materials and Wind Streaks on Mars: Examination of MGS TES Data in Western Arabia Terra

    NASA Technical Reports Server (NTRS)

    Bandfield, J. L.; Wyatt, M. B.; Christensen, P.; McSween, H. Y., Jr.

    2001-01-01

    Basalt and andesite surface compositions are identified within individual low albedo intracrater features and adjacent dark wind streaks. High resolution mapping of compositional heterogeneities may help constrain origin hypotheses for these features. Additional information is contained in the original extended abstract.

  15. First report of bacterial streak of fennel (Foeniculum vulgare) in California caused by Pseudomonas syringae pv. apii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new bacterial streak disease appeared on fennel leaves, stems and bulbs grown in Salinas California production fields. Initial symptoms consisted of small black lesions on stems that spread down the stem to the bulbs and up the stem to leaves as the disease progressed. The disease rendered the pl...

  16. Effect of temperature on wheat streak mosaic virus replication and movement in resistant and susceptible wheat cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is an economically important virus causing annual average yield losses of ~2-3% in winter wheat across the Great Plains. Temperature is one of the most important environmental factors that influences disease development and severity. The objective of this study was t...

  17. Wheat streak mosaic virus P1: Defining the minimal region required for the suppression of RNA silencing activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is the most economically important wheat virus in the Great Plains region of USA. WSMV is the type species of the genus Tritimovirus in the family Potyviridae, and is transmitted by the wheat curl mite, Aceria tosichella Keifer. Previously, we reported that WSMV P1 f...

  18. Introgression of chromosome segments from multiple alien species in wheat breeding lines with wheat streak mosaic virus resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyramiding of alien-derived Wheat streak mosaic virus (WSMV) resistance and resistance enhancing genes in wheat is a costeffective and environmentally safe strategy for disease control. PCR-based markers and cytogenetic analysis with genomic in situ hybridisation were applied to identify alien chrom...

  19. Modified ecometric technique (four-quadrant sequential streak) to evaluate Campylobacter enrichment broth proficiency in suppressing background microflora

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecometric technique is a semi-quantitative scoring method used for quality control of culture media in microbiological laboratories. The technique involves inoculation with defined populations of specific culture onto solid media via a standardized chronological streaking technique, leading to ever-...

  20. Identification of distinct functions of Wheat streak mosaic virus coat protein in virion assembly and virus movement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) is the type member of Tritimovirus genus of the family Potyviridae. The WSMV coat protein (CP) was subjected to point and deletion mutation analyses. WSMV mutants changing aspartic acid residues at amino acid (aa) positions 289, 290, 326, 333, and 334 to alanine elic...

  1. Winter wheat cultivars with temperature sensitive resistance to wheat streak mosaic virus do not recover from early season infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV), Triticum mosaic virus, and Wheat mosaic virus, all vectored by the wheat curl mite Aceria tosichella Keifer, frequently cause devastating losses to winter wheat production throughout the central and western Great Plains. Resistant 'Mace' and 'RonL' are commercially ...

  2. Cholestasis in children with portal vein obstruction.

    PubMed

    Gauthier-Villars, Marion; Franchi, Stéphanie; Gauthier, Frédéric; Fabre, Monique; Pariente, Danièle; Bernard, Olivier

    2005-04-01

    We describe cholestasis as a result of bile duct abnormalities in 8 children with portal vein obstruction. In a clinical, biochemical and radiological investigation of 121 children with cavernous transformation of the portal vein seen between 1986 and 2000, 8 presented with jaundice, pruritus, and/or raised serum aminotransferases and/or gamma glutamyl transpeptidase (gamma GT) activities. Each displayed dilation and narrowing of intra- and/or extrahepatic bile ducts. Surgical decompression of the portal system (portal-systemic or Rex anastomosis) resulted in the regression of the signs of cholestasis in all children. We conclude that children with portal vein obstruction may exhibit clinically significant cholestasis as a result of external compression of the bile duct by the cavernoma.

  3. 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

  4. Pathogenesis of varicose veins - lessons from biomechanics.

    PubMed

    Pfisterer, Larissa; König, Gerd; Hecker, Markus; Korff, Thomas

    2014-03-01

    The development of varicose veins or chronic venous insufficiency is preceded by and associated with the pathophysiological remodelling of the venous wall. Recent work suggests that an increase in venous filling pressure is sufficient to promote varicose remodelling of veins by augmenting wall stress and activating venous endothelial and smooth muscle cells. In line with this, known risk factors such as prolonged standing or an obesity-induced increase in venous filling pressure may contribute to varicosis. This review focuses on biomechanically mediated mechanisms such as an increase in wall stress caused by venous hypertension or alterations in blood flow, which may be involved in the onset of varicose vein development. Finally, possible therapeutic options to counteract or delay the progress of this venous disease are discussed.

  5. Isolated Cortical Vein Thrombosis - The Cord Sign

    PubMed Central

    Sharma, Vijay K.; Teoh, Hock L

    2009-01-01

    Isolated cortical vein thrombosis is an uncommon condition and often difficult to diagnose, both clinically and radiologically. We report a case of a 38 years old man who presented with headache of new onset and clinical examination was unremarkable. The unenhanced brain CT did not reveal any abnormality. In view of unrelenting headache and partial seizures, we performed magnetic resonance imaging (with axial T1, T2 and gradient echo sequences, coronal FLAIR, diffusion weighted imaging as well as Gadolinium contrast-enhanced images) and magnetic resonance venography of the brain that revealed an isolated parietal cortical vein thrombosis with the rarely reported 'cord sign'. We report the clinical and radiological findings in our patient with isolated parietal cortical vein thrombosis. PMID:22470649

  6. Redox alters yellow dragonflies into red.

    PubMed

    Futahashi, Ryo; Kurita, Ryoji; Mano, Hiroaki; Fukatsu, Takema

    2012-07-31

    Body color change associated with sexual maturation--so-called nuptial coloration--is commonly found in diverse vertebrates and invertebrates, and plays important roles for their reproductive success. In some dragonflies, whereas females and young males are yellowish in color, aged males turn vivid red upon sexual maturation. The male-specific coloration plays pivotal roles in, for example, mating and territoriality, but molecular basis of the sex-related transition in body coloration of the dragonflies has been poorly understood. Here we demonstrate that yellow/red color changes in the dragonflies are regulated by redox states of epidermal ommochrome pigments. Ratios of reduced-form pigments to oxidized-form pigments were significantly higher in red mature males than yellow females and immature males. The ommochrome pigments extracted from the dragonflies changed color according to redox conditions in vitro: from red to yellow in the presence of oxidant and from yellow to red in the presence of reductant. By injecting the reductant solution into live insects, the yellow-to-red color change was experimentally reproduced in vivo in immature males and mature females. Discontinuous yellow/red mosaicism was observed in body coloration of gynandromorphic dragonflies, suggesting a cell-autonomous regulation over the redox states of the ommochrome pigments. Our finding extends the mechanical repertoire of pigment-based body color change in animals, and highlights an impressively simple molecular mechanism that regulates an ecologically important color trait.

  7. Redox alters yellow dragonflies into red

    PubMed Central

    Futahashi, Ryo; Kurita, Ryoji; Mano, Hiroaki; Fukatsu, Takema

    2012-01-01

    Body color change associated with sexual maturation—so-called nuptial coloration—is commonly found in diverse vertebrates and invertebrates, and plays important roles for their reproductive success. In some dragonflies, whereas females and young males are yellowish in color, aged males turn vivid red upon sexual maturation. The male-specific coloration plays pivotal roles in, for example, mating and territoriality, but molecular basis of the sex-related transition in body coloration of the dragonflies has been poorly understood. Here we demonstrate that yellow/red color changes in the dragonflies are regulated by redox states of epidermal ommochrome pigments. Ratios of reduced-form pigments to oxidized-form pigments were significantly higher in red mature males than yellow females and immature males. The ommochrome pigments extracted from the dragonflies changed color according to redox conditions in vitro: from red to yellow in the presence of oxidant and from yellow to red in the presence of reductant. By injecting the reductant solution into live insects, the yellow-to-red color change was experimentally reproduced in vivo in immature males and mature females. Discontinuous yellow/red mosaicism was observed in body coloration of gynandromorphic dragonflies, suggesting a cell-autonomous regulation over the redox states of the ommochrome pigments. Our finding extends the mechanical repertoire of pigment-based body color change in animals, and highlights an impressively simple molecular mechanism that regulates an ecologically important color trait. PMID:22778425

  8. Time-resolved measurements with streaked diffraction patterns from electrons generated in laser plasma wakefield

    NASA Astrophysics Data System (ADS)

    He, Zhaohan; Nees, John; Hou, Bixue; Krushelnick, Karl; Thomas, Alec; Beaurepaire, Benoît; Malka, Victor; Faure, Jérôme

    2013-10-01

    Femtosecond bunches of electrons with relativistic to ultra-relativistic energies can be robustly produced in laser plasma wakefield accelerators (LWFA). Scaling the electron energy down to sub-relativistic and MeV level using a millijoule laser system will make such electron source a promising candidate for ultrafast electron diffraction (UED) applications due to the intrinsic short bunch duration and perfect synchronization with the optical pump. Recent results of electron diffraction from a single crystal gold foil, using LWFA electrons driven by 8-mJ, 35-fs laser pulses at 500 Hz, will be presented. The accelerated electrons were collimated with a solenoid magnetic lens. By applying a small-angle tilt to the magnetic lens, the diffraction pattern can be streaked such that the temporal evolution is separated spatially on the detector screen after propagation. The observable time window and achievable temporal resolution are studied in pump-probe measurements of photo-induced heating on the gold foil.

  9. Time-resolved spectra of single-bubble sonoluminescence in sulfuric acid with a streak camera.

    PubMed

    Chen, Weizhong; Huang, Wei; Liang, Yue; Gao, Xianxian; Cui, Weicheng

    2008-09-01

    The time-resolved spectra of single-bubble sonoluminescence (SBSL) in sulfuric acid have been observed with a streak camera after a spectrograph. The spectral center evolves from infrared to ultraviolet gradually within a SBSL duration, which corresponds to an increase of temperature. The peak temperature within one sonoluminescence (SL) duration is 5-9 times higher than the average temperature based on the average spectrum in our experiment. Furthermore, the ratio of the peak temperature to average temperature increases with the increase of driving pressure. The SBSL flash dies out after a dramatic heating-up, and there is no cooling procedure observed at the time resolution of 110 SL duration, which is incompatible with the radius-related adiabatic heating model as the mechanism of SBSL.

  10. Time-resolved spectra of single-bubble sonoluminescence in sulfuric acid with a streak camera

    NASA Astrophysics Data System (ADS)

    Chen, Weizhong; Huang, Wei; Liang, Yue; Gao, Xianxian; Cui, Weicheng

    2008-09-01

    The time-resolved spectra of single-bubble sonoluminescence (SBSL) in sulfuric acid have been observed with a streak camera after a spectrograph. The spectral center evolves from infrared to ultraviolet gradually within a SBSL duration, which corresponds to an increase of temperature. The peak temperature within one sonoluminescence (SL) duration is 5 9 times higher than the average temperature based on the average spectrum in our experiment. Furthermore, the ratio of the peak temperature to average temperature increases with the increase of driving pressure. The SBSL flash dies out after a dramatic heating-up, and there is no cooling procedure observed at the time resolution of 1/10 SL duration, which is incompatible with the radius-related adiabatic heating model as the mechanism of SBSL.

  11. Integration of banana streak badnavirus into the Musa genome: molecular and cytogenetic evidence.

    PubMed

    Harper, G; Osuji, J O; Heslop-Harrison, J S; Hull, R

    1999-03-15

    Breeding and tissue culture of certain cultivars of bananas (Musa) have led to high levels of banana streak badnavirus (BSV) infection in progeny from symptomless parents. BSV DNA hybridized to genomic DNA of one such parent, Obino l'Ewai, suggesting integration of viral sequences. Sequencing of clones of Obino l'Ewai genomic DNA revealed an interface between BSV and Musa sequences and a complex BSV integrant. In situ hybridization revealed two different BSV sequence locations in Obino l'Ewai chromosomes and a complex arrangement of BSV and Musa sequences was shown by probing stretched DNA fibers. This is the first report of integrated sequences that possibly lead to a plant pararetrovirus episomal infection by a mechanism differing markedly from animal retroviral systems.

  12. A quill vibrating mechanism for a sounding apparatus in the streaked tenrec (Hemicentetes semispinosus).

    PubMed

    Endo, Hideki; Koyabu, Daisuke; Kimura, Junpei; Rakotondraparany, Felix; Matsui, Atsushi; Yonezawa, Takahiro; Shinohara, Akio; Hasegawa, Masami

    2010-05-01

    The streaked tenrec (Hemicentetes semispinosus) is equipped with a quill vibrating mechanism on the dorsal side of the caudal trunk that has evolved as an extraordinary sounding apparatus for communication. An arrangement of 15 or 16 light-brown quills was observed. Thickened cutaneous muscles were confirmed beneath quills. We named this structure the "quill vibrator disc" (QVD). The QVD was 16.8 mm long and 8.55 mm wide in a typical adult. Longitudinal musculature symmetrical about the sagittal plane was developed in the QVD. Myocytes were found immunohistochemically to contain mainly fast myosin but not slow myosin. These findings indicate that the QVD is a specialized apparatus in the cutaneous muscle that contributes to the vibration of quills and to the production of sound for communication.

  13. The complete nucleotide sequence and genome organization of pea streak virus (genus Carlavirus).

    PubMed

    Su, Li; Li, Zhengnan; Bernardy, Mike; Wiersma, Paul A; Cheng, Zhihui; Xiang, Yu

    2015-10-01

    Pea streak virus (PeSV) is a member of the genus Carlavirus in the family Betaflexiviridae. Here, the first complete genome sequence of PeSV was determined by deep sequencing of a cDNA library constructed from dsRNA extracted from a PeSV-infected sample and Rapid Amplification of cDNA Ends (RACE) PCR. The PeSV genome consists of 8041 nucleotides excluding the poly(A) tail and contains six open reading frames (ORFs). The putative peptide encoded by the PeSV ORF6 has an estimated molecular mass of 6.6 kDa and shows no similarity to any known proteins. This differs from typical carlaviruses, whose ORF6 encodes a 12- to 18-kDa cysteine-rich nucleic-acid-binding protein.

  14. Antimicrobial Screening of Actinobacteria using a Modified Cross-Streak Method

    PubMed Central

    Velho-Pereira, Sonashia; Kamat, N M

    2011-01-01

    Out of the 30 actinobacterial cultures screened for antimicrobial activity, 28 cultures were found to produce active products against various pathogenic microorganisms such as Gram-negative, Gram-positive bacteria and yeast, using a modified cross streak method. The modified method helped in easy quantification of results and also in ruling out probable mutual antibiosis. The actinobacterial strains that showed the ability to produce antimicrobial compounds belonged to Streptomyces (53%), Micromonospora (13%) and Actinomadura (10%) genera. Streptomyces sp. strain MMA-5 showed the highest multispecific antibiosis efficiency score value. Broad antibiotic spectrum activity was exhibited by Streptomyces sp. strain MMA-2 and Micromonospora sp. strain MMA-8. The multidrug resistant human pathogenic yeast strain Candida albicans was inhibited by 18 actinobacterial strains. PMID:22303068

  15. Carrier-Envelope-Phase Characterization for an Isolated Attosecond Pulse by Angular Streaking

    NASA Astrophysics Data System (ADS)

    He, Pei-Lun; Ruiz, Camilo; He, Feng

    2016-05-01

    The carrier envelope phase (CEP) is a crucial parameter for a few-cycle laser pulse since it substantially determines the laser waveform. Stepping forward from infrared to extreme ultraviolet (EUV) pulses, we propose a strategy to directly characterize the CEP of an isolated attosecond pulse (IAP) by numerically simulating the tunneling ionization of a hydrogen atom in a combined IAP and phase-stabilized circularly polarized IR laser pulse. The fine modulations of the combined laser fields, due to the variation of the CEP of the IAP, are exponentially enlarged onto the distinct time-dependent tunneling ionization rate. Electrons released at different time with distinct tunneling ionization rates are angularly streaked to different directions. By measuring the resulting photoelectron momentum distribution, the CEP of the IAP can be retrieved. The characterization of the CEP of an IAP will open the possibility of capturing sub-EUV-cycle dynamics.

  16. Myosin II-mediated cell shape changes and cell intercalation contribute to primitive streak formation

    PubMed Central

    Song, Feifei; Sang, Helen M.; Martin, René; Knölker, Hans-Joachim; MacDonald, Michael P; Weijer, Cornelis J

    2016-01-01

    Primitive streak formation in the chick embryo involves large scale highly coordinated flows of over 100.000 cells in the epiblast. These large scale tissue flows and deformations can be correlated with specific anisotropic cell behaviours in the forming mesendoderm through a combined light-sheet microscopy and computational analysis. Relevant behaviours include apical contraction, elongation along the apical-basal axis followed by ingression as well as asynchronous directional cell intercalation of small groups of mesendoderm cells. Cell intercalation is associated with sequential, directional contraction of apical junctions, the onset, localisation and direction of which correlate strongly with the appearance of active Myosin II cables in aligned apical junctions in neighbouring cells. Use of a class specific Myosin inhibitors and gene specific knockdowns show that apical contraction and intercalation are Myosin II dependent and also reveal critical roles for Myosin I and Myosin V family members in the assembly of junctional Myosin II cables. PMID:25812521

  17. High-Resolving-Power, Streaked X-Ray Spectroscopy on the OMEGA EP Laser System

    NASA Astrophysics Data System (ADS)

    Nilson, P. M.; Ehrne, F.; Mileham, C.; Mastrosimone, D.; Jungquist, R. K.; Taylor, C.; Boni, R.; Hassett, J.; Stillman, C. R.; Ivancic, S. T.; Lonobile, D. J.; Kidder, R. W.; Shoup, M. J., III; Solodov, A. A.; Stoeckl, C.; Theobald, W.; Froula, D. H.; Hill, K. W.; Gao, L.; Bitter, M.; Efthimion, P.; Meyerhofer, D. D.

    2016-10-01

    A high-resolving-power, streaked x-ray spectrometer is being developed and tested on the OMEGA EP Laser System to study temperature-equilibration dynamics in rapidly heated solid matter. Temporal spectral shifts of the Cu Kα line in isochorically heated solid targets provide a fairly simple system where the spectrometer performance will be validated. The goal is to achieve a resolving power of several thousand and 2-ps temporal resolution. A time-integrating survey spectrometer has been developed and deployed on OMEGA EP to evaluate the throughput, focusing fidelity, and spectral resolution of two different crystal geometries. The results from these measurements will be presented and used to justify the down-selected time-resolved spectrometer design. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  18. Carrier-Envelope-Phase Characterization for an Isolated Attosecond Pulse by Angular Streaking.

    PubMed

    He, Pei-Lun; Ruiz, Camilo; He, Feng

    2016-05-20

    The carrier envelope phase (CEP) is a crucial parameter for a few-cycle laser pulse since it substantially determines the laser waveform. Stepping forward from infrared to extreme ultraviolet (EUV) pulses, we propose a strategy to directly characterize the CEP of an isolated attosecond pulse (IAP) by numerically simulating the tunneling ionization of a hydrogen atom in a combined IAP and phase-stabilized circularly polarized IR laser pulse. The fine modulations of the combined laser fields, due to the variation of the CEP of the IAP, are exponentially enlarged onto the distinct time-dependent tunneling ionization rate. Electrons released at different time with distinct tunneling ionization rates are angularly streaked to different directions. By measuring the resulting photoelectron momentum distribution, the CEP of the IAP can be retrieved. The characterization of the CEP of an IAP will open the possibility of capturing sub-EUV-cycle dynamics.

  19. Successful liver allograft inflow reconstruction with the right gastroepiploic vein.

    PubMed

    Pinheiro, Rafael S; Cruz, Ruy J; Nacif, Lucas S; Vane, Matheus F; D'Albuquerque, Luiz A C

    2016-02-01

    Portal vein thrombosis is a common complication in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusual case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric orthotopic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advantage of avoiding the need of venous jump graft.

  20. How Vein Sealing Boosts Fracture Opening

    NASA Astrophysics Data System (ADS)

    Nüchter, Jens-Alexander

    2015-04-01

    Veins from from cracks. As such, a stage of brittle failure and fracturing is to be set apart from a stage of opening and sealing. The process of fracture opening requires distortion of the host rocks to create space for the evolving vein. To keep a crack arrested and, at the same time, to widen or stabilize the cavity, the stress intensity factor K_I=(P-S3)(πa) must remain below the fracture toughness K_IC of the host rock, and P-S3 >0 (P and S3 denote pore fluid pressure and absolute minimum principal stress, respectively and 'a' refers to the half-length of the fracture). For purely elastic distortion of the host rocks, maximum aperture W0=K_IC (1-ν^2)/(E(π/8)^1/2))(2a)^1/2 depends on on K_IC, Poisson's ratio ν, and Young's modulus E of the host rocks. Owing to the low values for rock K_IC typically ranging between 0.1 and 1 MPa m^1/2, veins formed by purely elastic distortion of the host rocks are restricted to high aspect ratios 2a/W. In metamorphic rocks, veins with low aspect ratios are common; inelastic deformation and viscous creep in the host rocks must have contributed to final vein shapes. In the present study, I use finite element models to simulate fracture opening and cavity formation supported by viscous creep distributed in the host rock. Simulations are carried out on 2D plate models containing elliptical fractures. The walls of the fractures are coated by thin layers simulating incipient sealing; a residual cavity prevails in the centre of the model veins. Constant displacement is applied to the plate boundaries oriented normal to the cracks. I run a series of models with various viscosity contrasts between the rocks and the sealing. The results of these models indicate the following. (1) Fracture opening is most effective when the viscosity of the sealing ηs exceeds the viscosity of the host rocks ηr (2) The rate of fracture opening increases with increasing values for ηs/ηr . (3) An increase in the thickness of the sealing layer causes

  1. Conduits for Coronary Bypass: Vein Grafts

    PubMed Central

    Farkas, Emily A

    2012-01-01

    The saphenous vein has been the principal conduit for coronary bypass grafting from the beginning, circa 1970. This report briefly traces this history and concomitantly presents one surgeons experience and personal views on use of the vein graft. As such it is not exhaustive but meant to be practical with a modest number of references. The focus is that of providing guidance and perspective which may be at variance with that of others and recognizing that there may be many ways to accomplish the task at hand. Hopefully the surgeon in training/early career may find this instructive on the journey to surgical maturity. PMID:23130300

  2. Postpartum Ovarian Vein Thrombophlebitis with Staphylococcal Bacteremia

    PubMed Central

    Parino, Eduardo; Mulinaris, Eric; Saccomano, Edgardo; Gallo, Juan Cruz; Kohan, Gabriel

    2015-01-01

    A 34-year-old female patient presented with fever and right flank pain ten days after uncomplicated vaginal delivery. CT examination revealed right ovarian vein thrombosis and methicillin-resistant Staphylococcus aureus (MRSA) was isolated from blood cultures. No other source of bacteremia was found. Antibiotic therapy and anticoagulation with enoxaparin were instituted. Fourteen days after admission, she was discharged in good condition. Although a very uncommon complication after spontaneous vaginal delivery, septic ovarian vein thrombophlebitis should be suspected in cases of persistent puerperal fever when other diagnostic possibilities have been excluded. PMID:26221549

  3. Tracing dynamics of laser-induced fields on ultrathin foils using complementary imaging with streak deflectometry

    NASA Astrophysics Data System (ADS)

    Abicht, F.; Braenzel, J.; Priebe, G.; Koschitzki, Ch.; Andreev, A. A.; Nickles, P. V.; Sander, W.; Schnürer, M.

    2016-09-01

    We present a detailed study of the electric and magnetic fields, which are created on plasma vacuum interfaces as a result of highly intense laser-matter interactions. For the field generation ultrathin polymer foils (30-50 nm) were irradiated with high intensity femtosecond (1019 - 1020 W /cm2 ) and picosecond (˜1017 W /cm2 ) laser pulses with ultrahigh contrast (1010 - 1011 ). To determine the temporal evolution and the spatial distribution of these fields the proton streak deflectometry method has been developed further and applied in two different imaging configurations. It enabled us to gather complementary information about the investigated field structure, in particular about the influence of different field components (parallel and normal to the target surface) and the impact of a moving ion front. The applied ultrahigh laser contrast significantly increased the reproducibility of the experiment and improved the accuracy of the imaging method. In order to explain the experimental observations, which were obtained by applying ultrashort laser pulses, two different analytical models have been studied in detail. Their ability to reproduce the streak deflectometry measurements was tested on the basis of three-dimensional particle simulations. A modification and combination of the two models allowed for an extensive and accurate reproduction of the experimental results in both imaging configurations. The controlled change of the laser pulse duration from 50 femtoseconds to 2.7 picoseconds led to a transition of the dominating force acting on the probing proton beam at the rear side of the polymer foil. In the picosecond case the (v ⇀ x B ⇀ ) -term of the Lorentz force dominated over the counteracting E ⇀-field and was responsible for the direction of the net force. The applied proton deflectometry method allowed for an unambiguous determination of the magnetic field polarity at the rear side of the ultrathin foil.

  4. High density lipoprotein plasma fractions inhibit aortic fatty streaks in cholesterol-fed rabbits.

    PubMed

    Badimon, J J; Badimon, L; Galvez, A; Dische, R; Fuster, V

    1989-03-01

    The effects of in vivo administration of high density lipoprotein-very high density lipoprotein (HDL-VHDL) on the development of aortic fatty streaks were studied in cholesterol-fed rabbits. The rabbits received a 0.5% cholesterol-rich diet for 8 weeks. During this period, the HDL-VHDL group was intravenously administered with 50 mg/week of homologous HDL-VHDL protein; the control group received normal saline (0.9% NaCl). HDL-VHDL fraction was obtained at density range 1.063 to 1.25 gm/ml by ultracentrifugation of normal rabbit plasma. Along the study, plasma lipid levels followed a similar profile in both groups. At the completion of the study, atherosclerotic-like lipid-rich lesions covered 37.9 +/- 6% (X +/- SEM) of the intimal aortic surface in the control group, and 14.9 +/- 2.1% in the treated group (p less than 0.001). The values of total and free cholesterol, esterified cholesterol, and phospholipids deposited within vessel wall were significantly lower in the aortas of the HDL-VHDL treated group than those in the control group. Cholesterol accumulation in the livers was also significantly lower (p less than 0.01) in the treated group than in the control. We concluded that administration of homologous HDL-VHDL lipoprotein fraction to cholesterol-fed rabbits, dramatically inhibited the extent of aortic fatty streaks and lowered lipid deposition in the arterial wall and liver without modification of the plasma lipid levels.

  5. The ECM Moves during Primitive Streak Formation—Computation of ECM Versus Cellular Motion

    PubMed Central

    Zamir, Evan A; Rongish, Brenda J; Little, Charles D

    2008-01-01

    Galileo described the concept of motion relativity—motion with respect to a reference frame—in 1632. He noted that a person below deck would be unable to discern whether the boat was moving. Embryologists, while recognizing that embryonic tissues undergo large-scale deformations, have failed to account for relative motion when analyzing cell motility data. A century of scientific articles has advanced the concept that embryonic cells move (“migrate”) in an autonomous fashion such that, as time progresses, the cells and their progeny assemble an embryo. In sharp contrast, the motion of the surrounding extracellular matrix scaffold has been largely ignored/overlooked. We developed computational/optical methods that measure the extent embryonic cells move relative to the extracellular matrix. Our time-lapse data show that epiblastic cells largely move in concert with a sub-epiblastic extracellular matrix during stages 2 and 3 in primitive streak quail embryos. In other words, there is little cellular motion relative to the extracellular matrix scaffold—both components move together as a tissue. The extracellular matrix displacements exhibit bilateral vortical motion, convergence to the midline, and extension along the presumptive vertebral axis—all patterns previously attributed solely to cellular “migration.” Our time-resolved data pose new challenges for understanding how extracellular chemical (morphogen) gradients, widely hypothesized to guide cellular trajectories at early gastrulation stages, are maintained in this dynamic extracellular environment. We conclude that models describing primitive streak cellular guidance mechanisms must be able to account for sub-epiblastic extracellular matrix displacements.

  6. Streaked x-ray spectrometer having a discrete selection of Bragg geometries for Omega

    SciTech Connect

    Millecchia, M.; Regan, S. P.; Bahr, R. E.; Romanofsky, M.; Sorce, C.

    2012-10-15

    The streaked x-ray spectrometer (SXS) is used with streak cameras [D. H. Kalantar, P. M. Bell, R. L. Costa, B. A. Hammel, O. L. Landen, T. J. Orzechowski, J. D. Hares, and A. K. L. Dymoke-Bradshaw, in 22nd International Congress on High-Speed Photography and Photonics, edited by D. L. Paisley and A. M. Frank (SPIE, Bellingham, WA, 1997), Vol. 2869, p. 680] positioned with a ten-inch manipulator on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] and OMEGA EP [L. J. Waxer et al., Presented at CLEO/QELS 2008, San Jose, CA, 4-9 May 2008 (Paper JThB1)] for time-resolved, x-ray spectroscopy of laser-produced plasmas in the 1.4- to 20-keV photon-energy range. These experiments require measuring a portion of this photon-energy range to monitor a particular emission or absorption feature of interest. The SXS relies on a pinned mechanical reference system to create a discrete set of Bragg reflection geometries for a variety of crystals. A wide selection of spectral windows is achieved accurately and efficiently using this technique. It replaces the previous spectrometer designs that had a continuous Bragg angle adjustment and required a tedious alignment calibration procedure. The number of spectral windows needed for the SXS was determined by studying the spectral ranges selected by OMEGA users over the last decade. These selections are easily configured in the SXS using one of the 25 discrete Bragg reflection geometries and one of the six types of Bragg crystals, including two curved crystals.

  7. Streaked x-ray spectrometer having a discrete selection of Bragg geometries for Omega.

    PubMed

    Millecchia, M; Regan, S P; Bahr, R E; Romanofsky, M; Sorce, C

    2012-10-01

    The streaked x-ray spectrometer (SXS) is used with streak cameras [D. H. Kalantar, P. M. Bell, R. L. Costa, B. A. Hammel, O. L. Landen, T. J. Orzechowski, J. D. Hares, and A. K. L. Dymoke-Bradshaw, in 22nd International Congress on High-Speed Photography and Photonics, edited by D. L. Paisley and A. M. Frank (SPIE, Bellingham, WA, 1997), Vol. 2869, p. 680] positioned with a ten-inch manipulator on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] and OMEGA EP [L. J. Waxer et al., Presented at CLEO∕QELS 2008, San Jose, CA, 4-9 May 2008 (Paper JThB1)] for time-resolved, x-ray spectroscopy of laser-produced plasmas in the 1.4- to 20-keV photon-energy range. These experiments require measuring a portion of this photon-energy range to monitor a particular emission or absorption feature of interest. The SXS relies on a pinned mechanical reference system to create a discrete set of Bragg reflection geometries for a variety of crystals. A wide selection of spectral windows is achieved accurately and efficiently using this technique. It replaces the previous spectrometer designs that had a continuous Bragg angle adjustment and required a tedious alignment calibration procedure. The number of spectral windows needed for the SXS was determined by studying the spectral ranges selected by OMEGA users over the last decade. These selections are easily configured in the SXS using one of the 25 discrete Bragg reflection geometries and one of the six types of Bragg crystals, including two curved crystals.

  8. Transitional features in human atherosclerosis. Intimal thickening, cholesterol clefts, and cell loss in human aortic fatty streaks.

    PubMed Central

    Guyton, J. R.; Klemp, K. F.

    1993-01-01

    The possible transition from a subset of fatty streaks to fibrous plaques in human atherosclerosis has long been postulated, but transitional features in lesions have rarely been demonstrated. We examined human aortic fatty streaks to determine whether significant tendencies toward intimal thickening and toward deep extracellular lipid deposition might be found. To provide accurate ultrastructural assessment of lipid, tissues were processed by new electron microscopic cytochemical techniques. Unilateral fatty streaks exhibited a 60% increase in intimal thickness when compared to contralateral control tissue. Fat droplets in intimal cells accounted for approximately half of the increase; nonfat portions of cells and extracellular matrix accounted for the remainder. Six of 32 fatty streaks (19%) contained cholesterol clefts, which were found in the musculo-elastic (deep) layer of the intima or in the tunica media. Volume fractions occupied by cells in deep intima were reduced when cholesterol clefts were evident, suggesting loss of cells in early core regions. Light and electron microscopy showed structures consistent with lipid-rich core regions in lesions with cholesterol clefts and in a few lesions without cholesterol clefts. The findings of intimal thickening, core region formation, and disappearance of intimal cells constitute new evidence that some fatty streaks are progressive lesions and sites of eventual fibrous plaque development. The findings also suggest that the lipid-rich core region does not originate primarily from the debris of dead foam cells in the superficial intima, but instead arises from lipids accumulating gradually in the extracellular matrix of the deep intima. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:8238260

  9. Infraclavicular access to the axillary vein - new possibilities for the catheterization of the central veins in the intensive care unit.

    PubMed

    Gawda, Ryszard; Czarnik, Tomasz; Łysenko, Lidia

    2016-01-01

    Central vein cannulation is one of the most commonly performed procedures in intensive care. Traditionally, the jugular and subclavian vein are recommended as the first choice option. Nevertheless, these attempts are not always obtainable for critically ill patients. For this reason, the axillary vein seems to be a rational alternative approach. In this narrative review, we evaluate the usefulness of the infraclavicular access to the axillary vein. The existing evidence suggests that infraclavicular approach to the axillary vein is a reliable method of central vein catheterization, especially when performed with ultrasound guidance.

  10. Drosophila gypsy insulator and yellow enhancers regulate activity of yellow promoter through the same regulatory element.

    PubMed

    Melnikova, Larisa; Kostuchenko, Margarita; Silicheva, Margarita; Georgiev, Pavel

    2008-04-01

    There is ample evidence that the enhancers of a promoterless yellow locus in one homologous chromosome can activate the yellow promoter in the other chromosome where the enhancers are inactive or deleted, which is indicative of a high specificity of the enhancer-promoter interaction in yellow. In this paper, we have found that the yellow sequence from -100 to -69 is essential for stimulation of the heterologous eve (TATA-containing) and white (TATA-less) promoters by the yellow enhancers from a distance. However, the presence of this sequence is not required when the yellow enhancers are directly fused to the heterologous promoters or are activated by the yeast GAL4 activator. Unexpectedly, the same promoter proximal region defines previously described promoter-specific, long-distance repression of the yellow promoter by the gypsy insulator on the mod(mdg4) ( u1 ) background. These finding suggest that proteins bound to the -100 to -69 sequence are essential for communication between the yellow promoter and upstream regulatory elements.

  11. [Anatomicosurgical study of the superior mesenteric vein].

    PubMed

    Dell'Isola, C; Tucci, G F

    1991-01-01

    Results of an autoptic study of the superior mesenteric vein in thirty cadavers are reported. The anatomo-surgical patterns of the venous axis are emphasized. In fact, a better knowledge of this vessel allows an easier and safer surgical approach during pancreatic resections.

  12. Duodenal web with preduodenal portal vein.

    PubMed

    Golombek, S; Bilgi, J; Ukabiala, O

    1995-06-01

    This article described an unusual case of an infant with duodenal atresia and preduodenal portal vein without Down's syndrome or other anatomical anomalies associated with this condition. Duodenoduodenostomy was effective. Enteral feeding was re-established 72 hours post-operatively and the patient was discharged home one day later.

  13. 21 CFR 880.6980 - Vein stabilizer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 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...

  14. 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.

  15. Hepatic vein obstruction (Budd-Chiari)

    MedlinePlus

    ... your provider if: You have symptoms of hepatic vein obstruction You are being treated for this condition and you develop new symptoms Alternative Names Budd-Chiari syndrome; Hepatic veno-occlusive disease Images Digestive system Digestive system organs Blood clot formation ...

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

    MedlinePlus

    ... around the varicose vein. Signs of telangiectasias are clusters of red veins that you can see just under the surface of your skin. These clusters usually are found on the upper body, including ...

  17. Omental vein catheter thrombolysis for acute porto-mesenteric vein thrombosis.

    PubMed

    Fonseca, Annabelle L; Cleary, Muriel A; Cholewczynski, Walter; Sumpio, Bauer E; Atweh, Nabil A

    2013-05-01

    Mesenteric venous thrombosis (MVT) is an uncommon clinical condition with potential high morbidity. We report here a patient who presented with acute-onset MVT and bowel infarction, which was successfully ameliorated with intramesenteric vein thrombolytic therapy.

  18. A Finger Vein Identification Method Based on Template Matching

    NASA Astrophysics Data System (ADS)

    Zou, Hui; Zhang, Bing; Tao, Zhigang; Wang, Xiaoping

    2016-01-01

    New methods for extracting vein features from finger vein image and generating templates for matching are proposed. In the algorithm for generating templates, we proposed a parameter-templates quality factor (TQF) - to measure the quality of generated templates. So that we can use fewer finger vein samples to generate templates that meet the quality requirement of identification. The recognition accuracy of using proposed methods of finger vein feature extraction and template generation strategy for identification is 97.14%.

  19. An unusual complication of femoral vein catheterisation: pneumoperitoneum.

    PubMed

    Yildizdas, D; Tepe, T; Parlak, M; Akcali, M

    2007-12-01

    A 2-month-old girl with severe pneumonia required a central venous line. Femoral vein catheterisation was attempted but insertion was difficult. Pneumoperitoneum developed, which is a rare complication of femoral vein catheterisation. It is important when undertaking femoral vein catheterisation to use the correct landmarks in the femoral triangle below the inguinal ligament and an appropriate size of catheter.

  20. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  1. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  2. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  3. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  4. 21 CFR 880.6970 - Liquid crystal vein locator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Liquid crystal vein locator. 880.6970 Section 880... Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  5. Who Is at Risk for Deep Vein Thrombosis?

    MedlinePlus

    ... on Twitter. Who Is at Risk for Deep Vein Thrombosis? The risk factors for deep vein thrombosis (DVT) include: A history of DVT. Conditions or factors that make your blood thicker or more likely to clot than normal. Some inherited ... to a deep vein from surgery, a broken bone, or other trauma. ...

  6. Preduodenal portal vein in an adult--angiography and CT.

    PubMed

    Sasai, K; Sano, A; Nishizawa, S; Imanaka, K; Kuroda, Y

    1985-01-01

    We report on an adult case of preduodenal portal vein illustrated by computed tomography (CT) and angiography. These diagnostic modalities were initially performed to evaluate a coexisting pancreatic cancer. Contrast-enhanced CT demonstrated unusual positioning of the portal vein ventral to the duodenum. The superior mesenteric-portal vein, which was L-shaped and convexly caudad, strongly suggested this anomalous condition.

  7. Venous thrombosis in subclavian, axillary, brachial veins with extension to internal jugular vein, right sigmoid sinus and simultaneous pulmonary embolism

    PubMed Central

    Tamizifar, Babak; Beigi, Arash; Rismankarzadeh, Maryam

    2013-01-01

    We present a rare case of Venous Thrombosis in Subclavian, Axillary, Brachial Veins with extension to Internal Jugular vein, right sigmoid sinus and simultaneous Pulmonary embolism during the treatment with low molecular weight heparin. PMID:23901341

  8. Induction of Yellow Pigmentation in Serratia marcescens

    PubMed Central

    Trias, Joaquim; Viñas, Miquel; Guinea, Jesús; Lorén, José G.

    1988-01-01

    The appearance of yellow pigmentation in nonpigmented strains of Serratia sp. has been demonstrated to be due to the production of a muconic acid, 2-hydroxy-5-carboxymethylmuconic acid semialdehyde. The 3,4-dihydroxyphenylacetate 2,3-dioxygenase responsible for the synthesis of this muconic acid was induced in all strains tested. Another muconic acid, the β-cis-cis-carboxymuconic acid, could also be synthesized from 3,4-dihydroxybenzoate, but this product was not colored. Mutants that were unable to grow on tyrosine and produced yellow pigment were isolated from nonpigmented strains. These mutants had properties similar to those of the yellow-pigmented strains. The ability to produce pigment may be more widespread among Serratia marcescens strains than is currently known. PMID:16347803

  9. Increasing use of yellow colors in Kyoto

    NASA Astrophysics Data System (ADS)

    Akita, Munehira; Nara, Iwao

    2002-06-01

    Colors used for commercial signboards, displayed outdoors as well as indoors through windows, such as a store sign, an advertising sign, a sky sign, a poster, a placard, and a billboard were extensively surveyed in Kyoto City, Japan, in 1998. The survey showed that various kinds of yellow painted signs have increased rapidly and invaded a center area and suburbs of the city. Vivid yellow, what we called it the Y98 virus, is specially considered a color unpleasantly matched to the city image of Kyoto which was the capital of Japan for nearly 1000 years (794 to 1868) and is endowed with cultural and historic heritage. Discussions trying to find out what we could do to prevent the rapid spread of a big commercial display painted with vivid yellows what we called 'the Y98 virus' over the city will be summarized in a main text.

  10. Yellow fever vaccination in the Americas.

    PubMed

    1984-01-01

    Outbreaks of yellow fever in recent years in the Americas have prompted concern about the possible urbanization of jungle fever. Vaccination, using the 17D strain of yellow fever virus, provides an effective, practical method of large scale protection against the disease. Because yellow fever can reappear in certain areas after a 2-year dormancy period, some countries maintain routine vaccination programs in areas where jungle yellow fever is endemic. The size of the endemic area (approximately half of South America), transportation and communication difficulties, and the inability to ensure a reliable cold chain are problems facing these programs. In addition, the problem of reaching dispersed and isolated populations has been addressed by the use of mobile teams, radio monitoring, and educational methods. During yellow fever outbreaks, many countries institute massive vaccination campaigns, targeted at temporary workers and migrants. Because epidemics in South America may involve extensive areas, these campaigns may not effectively address the problem. The ped-o-jet injector method, used in Brazil and Colombia, should be used in outbreak situations, as it is effective for large-scale vaccination. Vaccine by needle, suggested for maintenance programs, should be administered to those above 1 year of age. An efficient monitoring method to avoid revaccination, and to assess immunity, should be developed. The 17D strain produces seroconversion in 95% of recipients, and most is prepared in Brazil and Colombia. But, problems with storage methods, instability in seed lots, and difficulties in large-scale production were identified in 1981 by the Pan American Health Organization and WHO. The group recommended modernization of current production techniques and further research to develop a vaccine that could be produced in cell cultures. Brazil and Colombia have acted on these recommendations, modernizing vaccine production and researching thermostabilizing media for

  11. Segmentation and reconstruction of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset.

    PubMed

    Lou, Li; Liu, Shu Wei; Zhao, Zhen Mei; Heng, Pheng Ann; Tang, Yu Chun; Li, Zheng Ping; Xie, Yong Ming; Chui, Yim Pan

    2009-12-01

    Three-dimensional (3D) reconstruction of intrahepatic vessels is very useful in visualizing the complex anatomy of hepatic veins and intrahepatic portal vein. It also provides a 3D anatomic basis for diagnostic imaging and surgical operation on the liver. In the present study, we built a 3D digitized model of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset of the liver. The dataset was obtained using the digital freezing milling technique. The pre-reconstructed structures were identified and extracted, and then were segmented by the method of manual intervention. The digitized model of hepatic veins and intrahepatic portal vein was established using 3D medical visualization software. This model facilitated a continuous and dynamic displaying of the hepatic veins and intrahepatic portal vein at different orientations, which demonstrated the complicated relationship of adjacent hepatic veins and intrahepatic portal vein realistically in the 3D space. This study indicated that high-quality 2D images, precise data segmentation, and suitable 3D reconstruction methods ensured the reality and accuracy of the digital visualized model of hepatic veins and intrahepatic portal vein.

  12. Transcutaneous laser treatment of leg veins.

    PubMed

    Meesters, Arne A; Pitassi, Luiza H U; Campos, Valeria; Wolkerstorfer, Albert; Dierickx, Christine C

    2014-03-01

    Leg telangiectasias and reticular veins are a common complaint affecting more than 80% of the population to some extent. To date, the gold standard remains sclerotherapy for most patients. However, there may be some specific situations, where sclerotherapy is contraindicated such as needle phobia, allergy to certain sclerosing agents, and the presence of vessels smaller than the diameter of a 30-gauge needle (including telangiectatic matting). In these cases, transcutaneous laser therapy is a valuable alternative. Currently, different laser modalities have been proposed for the management of leg veins. The aim of this article is to present an overview of the basic principles of transcutaneous laser therapy of leg veins and to review the existing literature on this subject, including the most recent developments. The 532-nm potassium titanyl phosphate (KTP) laser, the 585-600-nm pulsed dye laser, the 755-nm alexandrite laser, various 800-983-nm diode lasers, and the 1,064-nm neodymium yttrium-aluminum-garnet (Nd:YAG) laser and various intense pulsed light sources have been investigated for this indication. The KTP and pulsed dye laser are an effective treatment option for small vessels (<1 mm). The side effect profile is usually favorable to that of longer wavelength modalities. For larger veins, the use of a longer wavelength is required. According to the scarce evidence available, the Nd:YAG laser produces better clinical results than the alexandrite and diode laser. Penetration depth is high, whereas absorption by melanin is low, making the Nd:YAG laser suitable for the treatment of larger and deeply located veins and for the treatment of patients with dark skin types. Clinical outcome of Nd:YAG laser therapy approximates that of sclerotherapy, although the latter is associated with less pain. New developments include (1) the use of a nonuniform pulse sequence or a dual-wavelength modality, inducing methemoglobin formation and enhancing the optical absorption

  13. [The fourth horseman: The yellow fever].

    PubMed

    Vallejos-Parás, Alfonso; Cabrera-Gaytán, David Alejandro

    2017-01-01

    Dengue virus three, Chikunguya and Zika have entered the national territory through the south of the country. Cases and outbreaks of yellow fever have now been identified in the Americas where it threatens to expand. Although Mexico has a robust epidemiological surveillance system for vector-borne diseases, our country must be alert in case of its possible introduction into the national territory. This paper presents theoretical assumptions based on factual data on the behavior of yellow fever in the Americas, as well as reflections on the epidemiological surveillance of vector-borne diseases.

  14. Habitat Suitability Index Models: Yellow perch

    USGS Publications Warehouse

    Krieger, Douglas A.; Terrell, James W.; Nelson, Patrick C.

    1983-01-01

    A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for yellow perch (Perca flavescens). The models are scaled to produce an index of habitat suitability between 0 (unsuitable habitat) to 1 (optimally suitable habitat) for riverine, lacustrine, and palustrine habitat in the 48 contiguous United States. Habitat Suitability Indexes (HSI's) are designed for use with the Habitat Evaluation Procedures developed by the U.S. Fish and Wildlife Service. Also included are discussions of Suitability Index (SI) curves as used in the Instream Flow Incremental Methodology (IFIM) and SI curves available for an IFIM analysis of yellow perch habitat.

  15. Dust Devils Seen Streaking Across Mars: PART II--They're the Work of the Devil!

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    [figure removed for brevity, see original site]

    In December 1999, the MOC team finally had an answer! A dust devil, shown in the above left figure, was caught in the act of creating a swirly, dark streak! An eerie sensation washed over the first team members who saw this picture--here was an event on Mars 'caught in the act' just hours before the picture was played back to Earth. A 'smoking gun.'

    The first dust devil seen making a streak--located in Promethei Terra (above, left)--was traveling from right (east) to left (west). A columnar shadow was cast by sunlight coming from the upper left. This shadow indicates the true shape of the dust devil. The bright dust devil itself does not look like a column because the picture was taken from a camera looking straight down on it. The dust devil is less than 100 meters (less than 100 yards) wide and the picture covers an area approximately 1.5 by 1.7 kilometers (about 1 by 1 mile).

    Dust devils are spinning, columnar vortices of wind that move across the landscape, pick up dust, and look somewhat like miniature tornadoes. Dust devils are a common occurrence in dry and desert landscapes on Earth as well as Mars. They form when the ground heats up during the day, warming the air immediately above the surface. As the warmed air nearest the surface begins to rise, it spins. The spinning column begins to move across the surface and picks up loose dust (if any is present). The dust makes the vortex visible and gives it the 'dust devil' or tornado-like appearance. On Earth, dust devils typically last for only a few minutes.

    The fourth picture (above, right) shows a surface in southwestern Terra Sirenum near 63oS, 168oW, that has seen the activity of so many dust devils that it looks like a plate of dark gray spaghetti. This image, taken in early summer during February 2000, covers an area 3 km wide and 30 km long (1.9 by 19 miles). In fact, a dust devil

  16. Recombination hotspots and host susceptibility modulate the adaptive value of recombination during maize streak virus evolution

    PubMed Central

    2011-01-01

    Background Maize streak virus -strain A (MSV-A; Genus Mastrevirus, Family Geminiviridae), the maize-adapted strain of MSV that causes maize streak disease throughout sub-Saharan Africa, probably arose between 100 and 200 years ago via homologous recombination between two MSV strains adapted to wild grasses. MSV recombination experiments and analyses of natural MSV recombination patterns have revealed that this recombination event entailed the exchange of the movement protein - coat protein gene cassette, bounded by the two genomic regions most prone to recombination in mastrevirus genomes; the first surrounding the virion-strand origin of replication, and the second around the interface between the coat protein gene and the short intergenic region. Therefore, aside from the likely adaptive advantages presented by a modular exchange of this cassette, these specific breakpoints may have been largely predetermined by the underlying mechanisms of mastrevirus recombination. To investigate this hypothesis, we constructed artificial, low-fitness, reciprocal chimaeric MSV genomes using alternating genomic segments from two MSV strains; a grass-adapted MSV-B, and a maize-adapted MSV-A. Between them, each pair of reciprocal chimaeric genomes represented all of the genetic material required to reconstruct - via recombination - the highly maize-adapted MSV-A genotype, MSV-MatA. We then co-infected a selection of differentially MSV-resistant maize genotypes with pairs of reciprocal chimaeras to determine the efficiency with which recombination would give rise to high-fitness progeny genomes resembling MSV-MatA. Results Recombinants resembling MSV-MatA invariably arose in all of our experiments. However, the accuracy and efficiency with which the MSV-MatA genotype was recovered across all replicates of each experiment depended on the MSV susceptibility of the maize genotypes used and the precise positions - in relation to known recombination hotspots - of the breakpoints

  17. Aorto-coronary vein graft 'Y' anastomosis made easy.

    PubMed

    Jarvis, Martin Amadee

    2011-10-01

    Vein graft-to-vein graft anastomosis, creating a 'Y' graft, is a useful technique when there is a lack of good-quality autologous vein to perform individual aorto-coronary bypass grafts or when the ascending aorta is short or atheromatous, limiting the space for proximal graft anastomosis. Unlike artery-to-artery composite grafts, which are resistant to flow-limiting technique-based distortions, the accurate construction of vein-to-vein anastomoses is critical. A technique is described that facilitates accurate placement of the anastomosis that prevents kinking, twisting or displacement.

  18. [Clinical estimation of the central vein catheterization in phthysiosurgical patients].

    PubMed

    Opanasenko, M S; Levanda, L I; Kononenko, V A; Klymenko, V I; Tereshkovych, O V; Kalenychenko, M I; Konik, B M; Obrems'ka, O K; Demus, R S; Kshanovs'kyĭ, O E

    2013-04-01

    The issue of actuality of the central veins catheterization application was studied in phthysiosurgical patients. The author's view, concerning indications and choosing of the central vein catheterization side, was presented. The data, concerning frequency of the certain veins catheterization, were adduced. General succeeding in performing central veins catheterization have had constituted 96%. While having complications rate of 11.8%, this included mechanical--8.2%, thrombotic--2.3%, infective--1.3%. There was substantiated one of the most optimal and secure procedure among central accesses--the internal jugular vein catheterization.

  19. Internal vein texture and vein evolution of the epithermal Shila-Paula district, southern Peru

    NASA Astrophysics Data System (ADS)

    Chauvet, Alain; Bailly, Laurent; André, Anne-Sylvie; Monié, Patrick; Cassard, Daniel; Tajada, Fernando Llosa; Vargas, Juan Rosas; Tuduri, Johann

    2006-07-01

    The epithermal Shila-Paula Au-Ag district is characterized by numerous veins hosted in Tertiary volcanic rocks of the Western Cordillera (southern Peru). Field studies of the ore bodies reveal a systematic association of a main E-W vein with secondary N55-60°W veins—two directions that are also reflected by the orientation of fluid-inclusion planes in quartz crystals of the host rock. In areas where this pattern is not recognized, such as the Apacheta sector, vein emplacement seems to have been guided by regional N40°E and N40°W fractures. Two main vein-filling stages are identified. stage 1 is a quartz-adularia-pyrite-galena-sphalerite-chalcopyrite-electrum-Mn silicate-carbonate assemblage that fills the main E-W veins. stage 2, which contains most of the precious-metal mineralization, is divided into pre-bonanza and bonanza substages. The pre-bonanza substage consists of a quartz-adularia-carbonate assemblage that is observed within the secondary N45-60°W veins, in veinlets that cut the stage 1 assemblage, and in final open-space fillings. The two latter structures are finally filled by the bonanza substage characterized by a Fe-poor sphalerite-chalcopyrite-pyrite-galena-tennantite-tetrahedrite-polybasite-pearceite-electrum assemblage. The ore in the main veins is systematically brecciated, whereas the ore in the secondary veins and geodes is characteristic of open-space crystallization. Microthermometric measurements on sphalerite from both stages and on quartz and calcite from stage 2 indicate a salinity range of 0 to 15.5 wt% NaCl equivalent and homogenization temperatures bracketed between 200 and 330°C. Secondary CO2-, N2- and H2S-bearing fluid inclusions are also identified. The age of vein emplacement, based on 40Ar/39Ar ages obtained on adularia of different veins, is estimated at around 11 Ma, with some overlap between adularia of stage 1 (11.4±0.4 Ma) and of stage 2 (10.8±0.3 Ma). A three-phase tectonic model has been constructed to explain the

  20. Transmission grating streaked spectrometer for the diagnosis of soft x-ray emission from ultrahigh intensity laser heated targets

    SciTech Connect

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

    2004-10-01

    A free-standing gold transmission grating with a period of 5000 A has been coupled to a soft x-ray sensitive streak camera with a limiting temporal resolution of 10 ps. The streak camera is equipped with a caesium iodide transmission photocathode and observations have been made in the 10-100 A regime. For a small source (200 {mu}m diameter) the spectral resolution is predicted to be around 2.5 A. This has been confirmed by examination of the Lyman-{alpha} line in hydrogen-like laser heated boron. A recorded linewidth of 2.44 A is demonstrated. The instrument has been used to diagnose the soft x-ray emission from a plastic (CH) foil target heated by an ultra-intense (2x10{sup 20} W cm{sup -2}) laser pulse.

  1. Transmission grating streaked spectrometer for the diagnosis of soft x-ray emission from ultrahigh intensity laser heated targets

    NASA Astrophysics Data System (ADS)

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

    2004-10-01

    A free-standing gold transmission grating with a period of 5000 Å has been coupled to a soft x-ray sensitive streak camera with a limiting temporal resolution of 10 ps. The streak camera is equipped with a caesium iodide transmission photocathode and observations have been made in the 10-100 Å regime. For a small source (200 μm diameter) the spectral resolution is predicted to be around 2.5 Å. This has been confirmed by examination of the Lyman-α line in hydrogen-like laser heated boron. A recorded linewidth of 2.44 Å is demonstrated. The instrument has been used to diagnose the soft x-ray emission from a plastic (CH) foil target heated by an ultra-intense (2×1020 W cm-2) laser pulse.

  2. The President's Day cyclone 17-19 February 1979: An analysis of jet streak interactions prior to cyclogenesis

    NASA Technical Reports Server (NTRS)

    Uccellini, L. W.; Kocin, P. J.; Walsh, C. H.

    1981-01-01

    The President's Day cyclone, produced record breaking snowfall along the East Coast of the United States in February 1979. Conventional radiosonde data, SMS GOES infrared imagery and LFM 2 model diagnostics were used to analyze the interaction of upper and lower tropospheric jet streaks prior to cyclogenesis. The analysis reveals that a series of complex scale interactive processes is responsible for the development of the intense cyclone. The evolution of the subsynoptic scale mass and momentum fields prior to and during the period of rapid development of the President's Day cyclone utilizing conventional data and SMS GOES imagery is documented. The interaction between upper and lower tropospheric jet streaks which occurred prior to the onset of cyclogenesis is discussed as well as the possible effects of terrain modified airflow within the precyclogenesis environment. Possible deficiencies in the LFM-2 initial wind fields that could have been responsible, in part, for the poor numerical forecast are examined.

  3. Successful Portal Vein Stent Placement in a Child with Cavernomatous Replacement of the Portal Vein After Partial Liver Transplantation: The Importance of a Recognizable Portal Vein Remnant.

    PubMed

    Miraglia, Roberto; Maruzzelli, Luigi; Caruso, Settimo; Ricotta, Calogero; Riva, Silvia; Burgio, Gaetano; Spada, Marco; Luca, Angelo

    2015-12-01

    Late portal vein thrombosis with cavernomatous replacement has been reported in 4.5% of pediatric patients who have undergone partial liver transplantation. In such cases, minimally invasive radiological treatments have a high failure rate. We report a successful case of percutaneous recanalization of the portal vein remnant, and subsequent stent placement, in a pediatric patient who underwent left lateral split liver transplantation with cavernomatous replacement of the portal vein.

  4. Augmented reality based real-time subcutaneous vein imaging system

    PubMed Central

    Ai, Danni; Yang, Jian; Fan, Jingfan; Zhao, Yitian; Song, Xianzheng; Shen, Jianbing; Shao, Ling; Wang, Yongtian

    2016-01-01

    A novel 3D reconstruction and fast imaging system for subcutaneous veins by augmented reality is presented. The study was performed to reduce the failure rate and time required in intravenous injection by providing augmented vein structures that back-project superimposed veins on the skin surface of the hand. Images of the subcutaneous vein are captured by two industrial cameras with extra reflective near-infrared lights. The veins are then segmented by a multiple-feature clustering method. Vein structures captured by the two cameras are matched and reconstructed based on the epipolar constraint and homographic property. The skin surface is reconstructed by active structured light with spatial encoding values and fusion displayed with the reconstructed vein. The vein and skin surface are both reconstructed in the 3D space. Results show that the structures can be precisely back-projected to the back of the hand for further augmented display and visualization. The overall system performance is evaluated in terms of vein segmentation, accuracy of vein matching, feature points distance error, duration times, accuracy of skin reconstruction, and augmented display. All experiments are validated with sets of real vein data. The imaging and augmented system produces good imaging and augmented reality results with high speed. PMID:27446690

  5. Augmented reality based real-time subcutaneous vein imaging system.

    PubMed

    Ai, Danni; Yang, Jian; Fan, Jingfan; Zhao, Yitian; Song, Xianzheng; Shen, Jianbing; Shao, Ling; Wang, Yongtian

    2016-07-01

    A novel 3D reconstruction and fast imaging system for subcutaneous veins by augmented reality is presented. The study was performed to reduce the failure rate and time required in intravenous injection by providing augmented vein structures that back-project superimposed veins on the skin surface of the hand. Images of the subcutaneous vein are captured by two industrial cameras with extra reflective near-infrared lights. The veins are then segmented by a multiple-feature clustering method. Vein structures captured by the two cameras are matched and reconstructed based on the epipolar constraint and homographic property. The skin surface is reconstructed by active structured light with spatial encoding values and fusion displayed with the reconstructed vein. The vein and skin surface are both reconstructed in the 3D space. Results show that the structures can be precisely back-projected to the back of the hand for further augmented display and visualization. The overall system performance is evaluated in terms of vein segmentation, accuracy of vein matching, feature points distance error, duration times, accuracy of skin reconstruction, and augmented display. All experiments are validated with sets of real vein data. The imaging and augmented system produces good imaging and augmented reality results with high speed.

  6. Finger vein extraction using gradient normalization and principal curvature

    NASA Astrophysics Data System (ADS)

    Choi, Joon Hwan; Song, Wonseok; Kim, Taejeong; Lee, Seung-Rae; Kim, Hee Chan

    2009-02-01

    Finger vein authentication is a personal identification technology using finger vein images acquired by infrared imaging. It is one of the newest technologies in biometrics. Its main advantage over other biometrics is the low risk of forgery or theft, due to the fact that finger veins are not normally visible to others. Extracting finger vein patterns from infrared images is the most difficult part in finger vein authentication. Uneven illumination, varying tissues and bones, and changes in the physical conditions and the blood flow make the thickness and brightness of the same vein different in each acquisition. Accordingly, extracting finger veins at their accurate positions regardless of their thickness and brightness is necessary for accurate personal identification. For this purpose, we propose a new finger vein extraction method which is composed of gradient normalization, principal curvature calculation, and binarization. As local brightness variation has little effect on the curvature and as gradient normalization makes the curvature fairly uniform at vein pixels, our method effectively extracts finger vein patterns regardless of the vein thickness or brightness. In our experiment, the proposed method showed notable improvement as compared with the existing methods.

  7. Distributed Blowing and Suction for the Purpose of Streak Control in a Boundary Layer Subjected to a Favorable Pressure Gradient

    NASA Technical Reports Server (NTRS)

    Forgoston, Eric; Tumin, Anatoli; Ashpis, David E.

    2005-01-01

    An analysis of the optimal control by blowing and suction in order to generate stream- wise velocity streaks is presented. The problem is examined using an iterative process that employs the Parabolized Stability Equations for an incompressible uid along with its adjoint equations. In particular, distributions of blowing and suction are computed for both the normal and tangential velocity perturbations for various choices of parameters.

  8. Pulmonary vein stenosis: Etiology, diagnosis and management.

    PubMed

    Pazos-López, Pablo; García-Rodríguez, Cristina; Guitián-González, Alba; Paredes-Galán, Emilio; Álvarez-Moure, María Ángel De La Guarda; Rodríguez-Álvarez, Marta; Baz-Alonso, José Antonio; Teijeira-Fernández, Elvis; Calvo-Iglesias, Francisco Eugenio; Íñiguez-Romo, Andrés

    2016-01-26

    Pulmonary vein stenosis (PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques (transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS.

  9. Leuprolide acetate and central retinal vein occlusion.

    PubMed

    Federici, Thomas J

    2007-01-01

    A 63-year-old man suffered a central retinal vein occlusion 2 months after he began taking leuprolide acetate for prostate cancer. Despite control for possible systemic hypertension (126/90 mm Hg) and mild hypercholesterolemia (total cholesterol level =246 mg/dL [range: 16 to 200 mg/dL], high-density lipoprotein level =67 mg/dL [range: 40 to 59 mg/dL], and low-density lipoprotein level =144 mg/dL [range: 0 to 130 mg/dL]), progression of the venous occlusive disease occurred. Leuprolide acetate, which is associated with thromboembolic events and diffuse intravascular coagulation, may be implicated in central retinal vein occlusion.

  10. Leiomyosarcoma arising from the inferior mesenteric vein

    PubMed Central

    Clemente, Gennaro; Sarno, Gerardo; Barbaro, Brunella; Nuzzo, Gennaro

    2009-01-01

    Leyomiosarcomas arising from the portal/mesenteric venous system are very rare tumours, and only a few cases have been reported in the global literature. As the other leyomiosarcomas of vascular origin, they are associated with a poor prognosis. The present report describes the case of a 66-year-old woman with a leyomiosarcoma of the inferior mesenteric vein, unexpectedly found during a CT scan performed for another indication. A brief review of the literature is also given. The patient underwent radical surgical excision and enjoys a good health, without radiological signs of recurrence, 24 months after surgery. In this case, an early incidental diagnosis determined an early treatment and, probably, a favourable prognosis. This is the second case of leyomiosarcoma of the inferior mesenteric vein reported in the literature. PMID:21686492

  11. Endovascular Radiofrequency Ablation for Varicose Veins

    PubMed Central

    2011-01-01

    Executive Summary Objective The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost–effectiveness of endovascular radiofrequency ablation (RFA) for the treatment of primary symptomatic varicose veins. Background The Ontario Health Technology Advisory Committee (OHTAC) met on August 26th, 2010 to review the safety, effectiveness, durability, and cost-effectiveness of RFA for the treatment of primary symptomatic varicose veins based on an evidence-based review by the Medical Advisory Secretariat (MAS). Clinical Condition Varicose veins (VV) are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad

  12. Varicose vein therapy and nerve lesions.

    PubMed

    Hirsch, Tobias

    2017-03-01

    Treating varicose veins using endovenous thermal techniques - especially laser and radio frequency ablation - has emerged as an effective alternative to open surgery with stripping and high ligation. Even though these methods are very gentle and patient-friendly, they are nevertheless accompanied by risks and side effects. Compared to open surgical therapy, the risk of damage to peripheral and motor nerves is reduced; however, it still exists as a result of heat exposure and tumescent anaesthesia. Non-thermal methods that can be applied without tumescent anaesthesia have been introduced to the market. They pose a considerably lower risk of nerve lesions while proving to be much more effective. This paper investigates data on postoperative nerve damage and paraesthesia using internet research (PubMed). It analyses the current state of knowledge regarding non-thermal treatment methods and takes into account the latest developments in the use of cyanoacrylate to close insufficient saphenous veins.

  13. The great brain versus vein debate.

    PubMed

    Menon, Ravi S

    2012-08-15

    From the earliest fMRI experiments, it was quickly appreciated by those working with BOLD at high field that the signal change originated from visible veins whose spatial localization was relatively coarse ("the macrovasculature"), and smaller vessels ("the microvasculature") that were not individually visible in BOLD images. It was expected that a functional brain imaging technique that was predominantly sensitive to the macrovasculature would not have the same effective resolution as one sensitive to the microvasculature. Elimination of the venous signal and enhancement of the microvascular one offered the tantalizing ability to image columnar and lamellar structures in the brain and distinguished fMRI from its predecessor techniques. This article reviews a brief history of how these signal sources were first identified and separated and some of the controversy associated with the "brain versus vein" debate.

  14. Pulmonary vein stenosis: Etiology, diagnosis and management

    PubMed Central

    Pazos-López, Pablo; García-Rodríguez, Cristina; Guitián-González, Alba; Paredes-Galán, Emilio; Álvarez-Moure, María Ángel De La Guarda; Rodríguez-Álvarez, Marta; Baz-Alonso, José Antonio; Teijeira-Fernández, Elvis; Calvo-Iglesias, Francisco Eugenio; Íñiguez-Romo, Andrés

    2016-01-01

    Pulmonary vein stenosis (PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques (transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS. PMID:26839659

  15. A pilot/introducer needle for central vein cannulation.

    PubMed

    Suzuki, T; Kanazawa, M; Kinefuchi, Y; Fukuyama, H; Takiguchi, M; Yamamoto, M; Abe, K; Okuda, Y

    1995-12-01

    A kit for safe and easy insertion of a central vein cannula was devised. A small gauge (22 gauge) metal pilot needle was equipped with a Y-shaped hub which had a side-port to accept a small gauge (0.46 mm) Seldinger guide wire. Once the needle reached the vein, guidewire was threaded in through the side-port. There was no need to remove the pilot needle and no need to repeat vein puncture with a larger-bore needle. Three puncture methods were used with the kit: (1) the central approach via the internal jugular vein, (2) the supraclavicular approach via the junction of the internal jugular vein and subclavian vein, and (3) the infraclavicular approach via the subclavian vein. Each method was used on 20 patients, for total of 60 patients, with a high success rate. Less than 3 minutes were required from puncture to catheter insertion. No serious complications were encountered.

  16. Asymptomatic Pulmonary Vein Stenosis: Hemodynamic Adaptation and Successful Ablation

    PubMed Central

    Weinberg, Denis

    2016-01-01

    Pulmonary vein stenosis is a well-established possible complication following an atrial fibrillation ablation of pulmonary veins. Symptoms of pulmonary vein stenosis range from asymptomatic to severe exertional dyspnea. The number of asymptomatic patients with pulmonary vein stenosis is greater than originally estimated; moreover, only about 22% of severe pulmonary vein stenosis requires intervention. We present a patient with severe postatrial fibrillation (AF) ablation pulmonary vein (PV) stenosis, which was seen on multiple imaging modalities including cardiac computed tomography (CT) angiogram, lung perfusion scan, and pulmonary angiogram. This patient did not have any pulmonary symptoms. Hemodynamic changes within a stenosed pulmonary vein might not reflect the clinical severity of the obstruction if redistribution of pulmonary artery flow occurs. Our patient had an abnormal lung perfusion and ventilation (V/Q) scan, suggesting pulmonary artery blood flow redistribution. The patient ultimately underwent safe repeat atrial fibrillation ablation with successful elimination of arrhythmia. PMID:28105376

  17. Spontaneous thrombosis of vein of Galen malformation

    PubMed Central

    Kariyappa, Kalpana Devi; Krishnaswami, Murali; Gnanaprakasam, Francis; Ramachandran, Madan; Krishnaswamy, Visvanathan

    2016-01-01

    Vein of Galen malformation (VOGM) is a rare intracranial vascular malformation. Before the advent and advancement of various endovascular techniques, there was dismal prognosis. Rarely, this condition may spontaneously thrombose without the need for surgical or endovascular treatment with good prognosis. We report a case of an 8-month-old infant who had serial imaging, suggestive of VOGM and presented to us for further management, wherein the imaging revealed spontaneous thrombosis. PMID:27857804

  18. Streak instability and generation of hairpin-vortices by a slotted jet in channel crossflow: Experiments and linear stability analysis

    NASA Astrophysics Data System (ADS)

    Philip, Jimmy; Karp, Michael; Cohen, Jacob

    2016-01-01

    Streaks and hairpin-vortices are experimentally generated in a laminar plane Poiseuille crossflow by injecting a continuous jet through a streamwise slot normal to the crossflow, with air as the working media. Small disturbances form stable streaks, however, higher disturbances cause the formation of streaks which undergo instability leading to the generation of hairpin vortices. Particular emphasis is placed on the flow conditions close to the generation of hairpin-vortices. Measurements are carried out in the cases of natural and phase-locked disturbance employing smoke visualisation, particle image velocimetry, and hot-wire anemometry, which include, the dominant frequency, wavelength, and the disturbance shape (or eigenfunctions) associated with the coherent part of the velocity field. A linear stability analysis for both one- and two-dimensional base-flows is carried out to understand the mechanism of instability and good agreement of wavelength and eigenfunctions are obtained when compared to the experimental data, and a slight under-prediction of the growth-rates by the linear stability analysis consistent with the final nonlinear stages in transitional flows. Furthermore, an energy analysis for both the temporal and spatial stability analysis revels the dominance of the symmetric varicose mode, again, in agreement with the experiments, which is found to be governed by the balance of the wallnormal shear and dissipative effects rather than the spanwise shear. In all cases the anti-symmetric sinuous modes governed by the spanwise shear are found to be damped both in analysis and in our experiments.

  19. A Robust In-Situ Warp-Correction Algorithm For VISAR Streak Camera Data at the National Ignition Facility

    SciTech Connect

    Labaria, George R.; Warrick, Abbie L.; Celliers, Peter M.; Kalantar, Daniel H.

    2015-01-12

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a 192-beam pulsed laser system for high-energy-density physics experiments. Sophisticated diagnostics have been designed around key performance metrics to achieve ignition. The Velocity Interferometer System for Any Reflector (VISAR) is the primary diagnostic for measuring the timing of shocks induced into an ignition capsule. The VISAR system utilizes three streak cameras; these streak cameras are inherently nonlinear and require warp corrections to remove these nonlinear effects. A detailed calibration procedure has been developed with National Security Technologies (NSTec) and applied to the camera correction analysis in production. However, the camera nonlinearities drift over time, affecting the performance of this method. An in-situ fiber array is used to inject a comb of pulses to generate a calibration correction in order to meet the timing accuracy requirements of VISAR. We develop a robust algorithm for the analysis of the comb calibration images to generate the warp correction that is then applied to the data images. Our algorithm utilizes the method of thin-plate splines (TPS) to model the complex nonlinear distortions in the streak camera data. In this paper, we focus on the theory and implementation of the TPS warp-correction algorithm for the use in a production environment.

  20. Cassava brown streak virus has a rapidly evolving genome: implications for virus speciation, variability, diagnosis and host resistance

    PubMed Central

    Alicai, Titus; Ndunguru, Joseph; Sseruwagi, Peter; Tairo, Fred; Okao-Okuja, Geoffrey; Nanvubya, Resty; Kiiza, Lilliane; Kubatko, Laura; Kehoe, Monica A.; Boykin, Laura M.

    2016-01-01

    Cassava is a major staple food for about 800 million people in the tropics and sub-tropical regions of the world. Production of cassava is significantly hampered by cassava brown streak disease (CBSD), caused by Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). The disease is suppressing cassava yields in eastern Africa at an alarming rate. Previous studies have documented that CBSV is more devastating than UCBSV because it more readily infects both susceptible and tolerant cassava cultivars, resulting in greater yield losses. Using whole genome sequences from NGS data, we produced the first coalescent-based species tree estimate for CBSV and UCBSV. This species framework led to the finding that CBSV has a faster rate of evolution when compared with UCBSV. Furthermore, we have discovered that in CBSV, nonsynonymous substitutions are more predominant than synonymous substitution and occur across the entire genome. All comparative analyses between CBSV and UCBSV presented here suggest that CBSV may be outsmarting the cassava immune system, thus making it more devastating and harder to control. PMID:27808114