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1

Host range comparison of the causal agents of pepper yellow vein and lettuce big vein  

Microsoft Academic Search

A number of solanaceous and composite plant species were tested as hosts for the causal agents of pepper yellow vein (PYVA) and lettuce big vein (LBVA), transmitted by a pepper and a lettuce isolate ofOlpidium brassicae, respectively. The agents had the following artificial hosts in common:Lycopersicon esculentum, Solanum melongena, Physalis floridana, Nicandra physaloides, Lactuca sativa, Sonchus oleraceus andL. virosa. Capsicum

A. Th. B. Rast

1992-01-01

2

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

PubMed

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

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

2014-10-01

3

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

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. PMID:17294343

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

2007-01-01

4

Pathogenicity and insect transmission of a begomovirus complex between tomato yellow leaf curl virus and Ageratum yellow vein betasatellite.  

PubMed

Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein betasatellite (AYVB) are members of the genus Begomovirus (family Geminiviridae). TYLCV and AYVB have been found in Japan over the last 15 years, and are associated with tomato leaf curl and the tomato yellow leaf curl diseases (TYLCD). AYVB is also associated with some monopartite begomoviruses. We have cloned both TYLCV and AYVB and demonstrated that TYLCV can trans-replicate with AYVB in Nicotiana benthamiana and tomato plants. A mixed infection of TYLCV and AYVB induced more severe symptoms of upward leaf curl, stunting, vein thickening, and swelling compared with TYLCV infection alone. The symptoms induced by infection of AYVB included a rise in abnormal cell proliferation, and pigmentation around leaf vein tissues. This is the first study to show that a complex of TYLCV and AYVB can be transmitted by vector insects among tomato plants. These results indicate that TYLCV possesses the potential to induce severe TYLCD by associating with AYVB. PMID:22105924

Ueda, Shigenori; Onuki, Masatoshi; Yamashita, Masataka; Yamato, Yoichi

2012-04-01

5

The 3? terminal region is strictly required for clover yellow vein virus genome replication  

Microsoft Academic Search

Summary.  ?To identify the cis-element in the 3? terminal region of infectious cDNA required for replication of clover yellow vein virus (ClYVV), a series\\u000a of mutants with duplications or deletions of the 3? terminal non-coding region (3?-NCR) of the genome that did not affect\\u000a the ORFs in the genome was constructed. These were tested for infectivity, and the 3? terminal regions

H. Sekiguchi; Y. Tacahashi; I. Uyeda

2003-01-01

6

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

PubMed

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

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

2007-04-01

7

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

PubMed

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. PMID:21400195

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

2011-05-01

8

A Nanovirus-like DNA Component Associated with Yellow Vein Disease of Ageratum conyzoides: Evidence for Interfamilial Recombination between Plant DNA Viruses  

Microsoft Academic Search

Yellow vein disease of Ageratum conyzoides, a weed species that is widely distributed throughout Asia, has been attributed to infection by the geminivirus Ageratum yellow vein virus (AYVV). In addition to a single AYVV genomic component (DNA A), we have previously demonstrated that infected plants contain chimeric defective viral components, comprising DNA A and nongeminiviral sequences, that act as defective

Keith Saunders; John Stanley

1999-01-01

9

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

PubMed

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-?) of ~1,350 nucleotides in length associated with Croton yellow vein mosaic begomovirus (CYVMV) in croton plants. The expression of genes from DNA-? requires the begomovirus for packaged, replication, insect transmission and movement in plants. The present study demonstrates the effect of the ?C1 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 ?C1 gene accumulated cognate small-interfering RNAs and remained symptom-free after exposure to CYVMV and its satellite. These results suggest that ?C1 interferes with silencing mechanism. PMID:25086625

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

2014-11-01

10

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

PubMed Central

Background Many monopartite begomoviruses are associated with betasatellites, but only several promoters from which were isolated and studied. In this study, the ?C1 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 ?C1 open reading frame of MYVB and a series of deletions within this fragment were constructed and fused to the ?-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 ?C1 promoter of MYVB displayed a constitutive expression pattern and a 5?UTR Py-rich stretch motif regulated both ?C1 promoter activity and MYVB replication. PMID:23057573

2012-01-01

11

Host Range Studies for Tomato chlorosis virus , and Cucumber vein yellowing virus Transmitted by Bemisia  tabaci (Gennadius)  

Microsoft Academic Search

The Bemisia  tabaci (Gennadius) biotype B transmitted host range of Tomato chlorosis virus (ToCV), genus Crinivirus, Family Closteroviridae, and Cucumber vein yellowing virus (CVYV), genus Ipomovirus, Family Potyviridae, was studied. New experimental hosts were identified for each of these viruses. Seventeen species in eight plant families\\u000a were assessed as potential hosts for ToCV. Infection in asymptomatic Anthriscus  cereifolium (chervil) test

Jane Morris; Elspeth Steel; Penny Smith; Neil Boonham; Nicola Spence; Ian Barker

2006-01-01

12

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

PubMed

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

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

2014-01-01

13

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

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

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

2014-01-01

14

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

PubMed

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. PMID:23963765

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

2013-12-01

15

Strains of a new bipartite begomovirus, pepper yellow leaf curl Indonesia virus, in leaf-curl-diseased tomato and yellow-vein-diseased ageratum in Indonesia.  

PubMed

The complete nucleotide sequences of begomoviruses from pepper with leaf curl and yellowing symptoms, tomato with leaf curl symptoms, and ageratum with yellow vein in Indonesia were determined. On the basis of genome organization and sequence homology, they were proposed to belong to a new species, Pepper yellow leaf curl Indonesia virus (PepYLCIV), which includes the new strains PepYLCIV-Tomato and PepYLCIV-Ageratum. These viruses had bipartite genomes. Pepper virus DNAs from Indonesia (PepYLCIV, PepYLCIV-Tomato and PepYLCIV-Ageratum DNA-As) were noticeably distinct, forming a separate branch from the viruses infecting pepper. Considerable divergence was observed in the common region (CR) of the genomic components of PepYLCIV (77%), PepYLCIV-Tomato (82%) and PeYLCIV-Ageratum (75%). A stem-loop-forming region and a Rep-binding motif were identical in the CR of the three viruses. The CRs of PepYLCIV-Ageratum DNA-A was approximately 10 nucleotides longer than that of PepYLCIV DNA-A and PepYLCIV-Tomato DNA-A. A similar insertion was also found in the CR of PepYLCIV-Ageratum DNA-B. PepYLCIV DNA-A alone was infectious in pepper and Nicotiana benthamiana plants, and association with DNA-B increased symptom severity. PMID:19015934

Sakata, Jyun-Ji; Shibuya, Yutaka; Sharma, Pradeep; Ikegami, Masato

2008-01-01

16

The C2 protein of Bhendi yellow vein mosaic virus plays an important role in symptom determination and virus replication.  

PubMed

Bhendi yellow vein mosaic virus (BYVMV) that causes bhendi yellow vein mosaic disease is a monopartite begomovirus with an associated betasatellite. Previous studies have shown that C2 protein of BYVMV acts as a suppressor of post transcriptional gene silencing, activates transcription, localizes to nucleus, and interacts with karyopherin ?. To probe the role of C2 in symptom determination and virus replication, the infectious clones of BYVMV containing two stop codons in the C2 ORF were created and used for infection studies. The Nicotiana benthamiana plants infiltrated with the infectious clones harboring stop codons in the C2 ORF did not develop any symptoms unlike plants infiltrated with wild-type BYVMV. Southern blotting and real time PCR analysis revealed that the viral load was reduced drastically in the plants infected with BYVMV containing the nontranslatable version of C2 ORF. However, there was a recovery in viral DNA replication, when co-infiltrated with wild-type betasatellite. Hence we conclude that the C2 protein of BYVMV plays an important role in symptom determination and viral DNA replication. PMID:24122068

Chandran, Sam A; Jeyabharathy, C; Usha, R

2014-02-01

17

Detection of Cereal yellow dwarf virus using small interfering RNAs and enhanced infection rate with Cocksfoot streak virus in wild cocksfoot grass (Dactylis glomerata).  

PubMed

Small RNA sequences were obtained from leaf extracts of wild Dactylis glomerata (cocksfoot grass) using deep sequencing (454 Life Sciences, Roche Diagnostics), and were screened against virus sequences in GenBank using a local BLASTn search program (BioEdit). Putative small interfering (si)RNAs complementary in sequence to Cereal yellow dwarf virus (CYDV, genus Luteovirus) genomes were identified. Primer sequences were made against the "high scoring" siRNA sequences and RT-PCR was used to amplify a 438 bp CYDV fragment in total RNA extracts from D. glomerata leaves. Sequencing of the RT-PCR product confirmed the occurrence of a previously undescribed CYDV population with phylogenetic affinity to CYDV-RPS. In D. glomerata the CYDV infection rates were 42.3% (n=78) in 2008 and 50.0% (n=48) in 2009. Specific RT-PCR tests also showed that this D. glomerata population harboured Cocksfoot streak virus (CSV, genus Potyvirus). Dual infections by these viruses were observed in 20.5-22.9% of all plants tested in 2008-2009. Interestingly, infections of either CYDV or CSV enhanced the occurrence of the other virus in individual grasses. Opportunities are discussed for using siRNA sequencing approaches in virus survey and other ecology studies under field conditions. PMID:20558208

Pallett, Denise W; Ho, Thien; Cooper, Ian; Wang, Hui

2010-09-01

18

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

PubMed

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

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

2013-03-01

19

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

PubMed

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

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

2013-09-01

20

Identification of the virulence factors and suppressors of posttranscriptional gene silencing encoded by Ageratum yellow vein virus, a monopartite begomovirus.  

PubMed

Ageratum yellow vein disease (AYVD) is caused by the association of a Tomato leaf curl Java betasatellite [Indonesia:Indonesia 1:2003] (ToLCJB-[ID:ID1:03]) with a begomovirus component. Our previous results demonstrated that ToLCJB-[ID:ID:03] is essential for induction of leaf curl symptoms in plants and transgene expression of its betaC1 gene in Nicotiana benthamiana plants induces virus-like symptoms. Here we show that Ageratum yellow vein virus-Indonesia [Indonesia: Tomato] (AYVV-ID[ID:Tom]) alone could systemically infect the plants and induced upward leaf curl symptoms. ToLCJB-[ID:ID1:03] was required, in addition to AYVV-ID[ID:Tom], for induction of severe downward leaf curl disease in N. benthamiana plants. However, DNAbeta01fsbetaC1, which encompasses a frameshift mutation, did not induce severe symptoms in N. benthamiana when co-inoculated with AYVV-ID[ID:Tom]. The infectivity analysis of AYVV-ID[ID:Tom] and its associated betasatellite encoded genes using Potato virus X (PVX) vector were carried out in N. benthamiana, indicate that the V2 and betaC1 genes are symptom determinants. We have identified the DNA encoded V2 and its betasatellite, ToLCJB-[ID:ID1:03], encoded betaC1 proteins as efficient silencing suppressors of posttranscriptional gene silencing (PTGS) by using an Agrobacterium co-infiltration or heterologous PVX vector assays. However, the results also showed weak suppression of gene silencing activities for C2 and C4 induced by GFP and mRNA associated with GFP was detected. Furthermore, confocal imaging analysis of ToLCJB-[ID:ID1:03] betaC1 in the epidermal cells of N. benthamiana shows that this protein is accumulated towards the periphery of the cell and around the nucleus, however, V2 accumulated in the cell cytoplasm, C4 associated with plasma membrane and C2 exclusively targeted into nucleus. In this study, we identified as many as four distinct suppressors of RNA silencing encoded by AYVV-ID[ID:Tom] and its cognate betasatellite in the family Geminiviridae, counteracting innate antiviral response. PMID:20079777

Sharma, P; Ikegami, M; Kon, T

2010-04-01

21

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

PubMed

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

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

2011-01-01

22

[The C4 proteins of Ageratum yellow vein China virus and Stachytarpheta leaf curl virus are suppressors of RNA silencing].  

PubMed

RNA silencing is a highly conserved mechanism in many eukaryotic organisms that involves sequence-specific RNA degradation. One of the important roles of RNA silencing is antiviral infection. To counter this defense mechanism, many plant viruses have evolved or acquired functional proteins (suppressors) for suppression of RNA silencing. Geminiviruses are a family of small circular single-stranded DNA (ssDNA) viruses that cause severe diseases in major crop plants worldwide. AC2 (C2) and AC4 (C4) proteins of many geminiviruses were reported to be suppressors of RNA silencing. Ageratum yellow vein China virus (AYVCNV) and Stachytarpheta leaf curl virus are two distinct geminiviruses identified in China. In this study, the functions of C4 of AYVCNV and StaLCV were studied, analysis of infectivity of AYVCNV and StaLCV C4 genes using Tobacco rattle virus (TRV) vector were carried out in Nicotiana benthamiana plants, N. benthamiana plants expressing C4 can induce the virus-like symptoms, indicating that the C4 gene of AYVCNV or StaLCV is symptom determinant. In experiment of suppression of RNA silencing, C4 protein of AYVCNV or StaLCV can suppresses the local silencing of gfp in transgenic N. benthamiana plants (16c), suggests that both of them are suppressors of RNA silencing. The above results indicate that C4 of PMID:17436621

Xiong, Qing; Zhou, Xue-Ping

2007-02-01

23

Characterization of the cryptic AV3 promoter of ageratum yellow vein virus in prokaryotic and eukaryotic systems.  

PubMed

A cryptic prokaryotic promoter, designated AV3 promoter, has been previously identified in certain begomovirus genus, including ageratum yellow vein virus isolate NT (AYVV-NT). In this study, we demonstrated that the core nucleotides in the putative -10 and -35 boxes are necessary but not sufficient for promoter activity in Escherichia coli, and showed that AYVV-NT AV3 promoter could specifically interact with single-stranded DNA-binding protein and sigma 70 of E. coli involved in transcription. Several AYVV-NT-encoded proteins were found to increase the activity of AV3 promoter. The transcription start sites downstream to AV3 promoter were mapped to nucleotide positions 803 or 805 in E. coli, and 856 in Nicotiana benthamiana. The eukaryotic activity of AV3 promoter and the translatability of a short downstream open reading frame were further confirmed by using a green fluorescent protein reporter construct in yeast (Saccharomyces cerevisiae) cells. These results suggested that AV3 promoter might be a remnant of evolution that retained cryptic activity at present. PMID:25268755

Wang, Wei-Chen; Wu, Chia-Ying; Lai, Yi-Chin; Lin, Na-Sheng; Hsu, Yau-Heiu; Hu, Chung-Chi

2014-01-01

24

Characterization of the Cryptic AV3 Promoter of Ageratum Yellow Vein Virus in Prokaryotic and Eukaryotic Systems  

PubMed Central

A cryptic prokaryotic promoter, designated AV3 promoter, has been previously identified in certain begomovirus genus, including ageratum yellow vein virus isolate NT (AYVV-NT). In this study, we demonstrated that the core nucleotides in the putative ?10 and ?35 boxes are necessary but not sufficient for promoter activity in Escherichia coli, and showed that AYVV-NT AV3 promoter could specifically interact with single-stranded DNA-binding protein and sigma 70 of E. coli involved in transcription. Several AYVV-NT-encoded proteins were found to increase the activity of AV3 promoter. The transcription start sites downstream to AV3 promoter were mapped to nucleotide positions 803 or 805 in E. coli, and 856 in Nicotiana benthamiana. The eukaryotic activity of AV3 promoter and the translatability of a short downstream open reading frame were further confirmed by using a green fluorescent protein reporter construct in yeast (Saccharomyces cerevisiae) cells. These results suggested that AV3 promoter might be a remnant of evolution that retained cryptic activity at present. PMID:25268755

Wang, Wei-Chen; Wu, Chia-Ying; Lai, Yi-Chin; Lin, Na-Sheng; Hsu, Yau-Heiu; Hu, Chung-Chi

2014-01-01

25

Replication promiscuity of DNA-beta satellites associated with monopartite begomoviruses; deletion mutagenesis of the Ageratum yellow vein virus DNA-beta satellite localizes sequences involved in replication.  

PubMed

Pseudorecombination studies in Nicotiana benthamiana demonstrate that Ageratum yellow vein virus (AYVV) and Eupatorium yellow vein virus (EpYVV) can functionally interact with DNA-beta satellites associated with AYVV, EpYVV, cotton leaf curl Multan virus (CLCuMV) and honeysuckle yellow vein virus (HYVV). In contrast, CLCuMV shows some specificity in its ability to interact with distinct satellites and HYVV is able to interact only with its own satellite. Using an N. benthamiana leaf disk assay, we have demonstrated that HYVV is unable to trans-replicate other satellites. To investigate the basis of trans-replication compatibility, deletion mutagenesis of AYVV DNA-beta has been used to localize the origin of replication to approximately 360 nt, encompassing the ubiquitous nonanucleotide/stem-loop structure, satellite conserved region (SCR) and part of the intergenic region immediately upstream of the SCR. Additional deletions within this intergenic region have identified a region that is essential for replication. The capacity for DNA-beta satellites to functionally interact with distinct geminivirus species and its implications for disease diversification are discussed. PMID:19008407

Saunders, Keith; Briddon, Rob W; Stanley, John

2008-12-01

26

Wind Streaks  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 17 September 2003

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

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

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

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

2003-01-01

27

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

PubMed

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. PMID:23307365

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

2013-06-01

28

Primitive Streak (dorsal view)  

NSDL National Science Digital Library

This FlashTM animation is the first of a seven part series that presents the primitive streak from different angles. This installment displays the dorsal view, which provides an overview of elongation and regression. Epiblast is seen migrating medially, towards and into the streak. The appearance of the neural tube and somites demonstrates that morphogenesis commences before the streak recedes away.

PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

2011-06-23

29

Breakdown of host resistance by independent evolutionary lineages of Beet necrotic yellow vein virus involves a parallel c/u mutation in its p25 gene.  

PubMed

ABSTRACT Breakdown of sugar beet Rz1-mediated resistance against Beet necrotic yellow vein virus (BNYVV) infection was previously found, by reverse genetics, to be caused by a single mutation in its p25 gene. The possibility of alternative breaking mutations, however, has not been discarded. To explore the natural diversity of BNYVV in the field and its effects on overcoming Rz1, wild-type (WT) and resistance-breaking (RB) p25 genes from diverse production regions of North America were characterized. The relative titer of WT p25 was inversely correlated with disease expression in Rz1 plants from Minnesota and California. In Minnesota, the predominant WT p25 encoded the A(67)C(68) amino acid signature whereas, in California, it encoded A(67)L(68). In both locations, these WT signatures were associated with asymptomatic BNYVV infections of Rz1 cultivars. Further analyses of symptomatic resistant plants revealed that, in Minnesota, WT A(67)C(68) was replaced by V(67)C(68) whereas, in California, WT A(67)L(68) was replaced by V(67)L(68). Therefore, V(67) was apparently critical in overcoming Rz1 in both pathosystems. The greater genetic distances between isolates from different geographic regions rather than between WT and RB from the same location indicate that the underlying C to U transition originated independently in both BNYVV lineages. PMID:20055646

Acosta-Leal, Rodolfo; Bryan, Becky K; Smith, Jessica T; Rush, Charles M

2010-02-01

30

Safflor yellow B suppresses angiotensin II-mediated human umbilical vein cell injury via regulation of Bcl-2/p22(phox) expression.  

PubMed

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(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. PMID:23994555

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

2013-11-15

31

A series of eIF4E alleles at the Bc-3 locus are associated with recessive resistance to Clover yellow vein virus in common bean.  

PubMed

Clover yellow vein virus (ClYVV) is capable of causing severe damage to common bean (Phaseolus vulgaris L.) production worldwide. The snap bean market class is particularly vulnerable because infection may lead to distortion and necrosis of the fresh green pods and rejection of the harvest. Three putatively independent recessive genes (cyv, desc, bc-3) have been reported to condition resistance to ClYVV; however, their allelic relationships have not been resolved. We identified, evaluated, and characterized the phenotypic and molecular genetic variation present in 21 informative common bean genotypes for resistance to ClYVV. Allelism testing phenotypes from multiple populations provided clear evidence that the three genes were a series of recessive alleles at the Bc-3 locus that condition unique potyvirus strain- and species-specific resistance spectra. Candidate gene analysis revealed complete association between the recessive resistance alleles and unique patterns of predicted amino acid substitutions in P. vulgaris eukaryotic translation initiation factor 4E (PveIF4E). This led to the discovery and characterization of two novel PveIF4E alleles associated with resistance to ClYVV, PveIF4E (3) , and PveIF4E (4) . We developed KASPar allele-specific SNP genotyping assays and demonstrated their ability to accurately detect and differentiate all of the PveIF4E haplotypes present in the germplasm, allelism testing, and in three separate segregating populations. The results contribute to an enhanced understanding and accessibility of the important potyvirus resistance conditioned by recessive alleles at Bc-3. The KASPar assays should be useful to further enable germplasm exploration, allelic discrimination, and marker-assisted introgression of bc-3 alleles in common bean. PMID:23933781

Hart, John P; Griffiths, Phillip D

2013-11-01

32

The cysteine-rich proteins of beet necrotic yellow vein virus and tobacco rattle virus contribute to efficient suppression of silencing in roots.  

PubMed

Many plant viruses encode proteins that suppress RNA silencing, but little is known about the activity of silencing suppressors in roots. This study examined differences in the silencing suppression activity of different viruses in leaves and roots of Nicotiana benthamiana plants. Infection by tobacco mosaic virus, potato virus Y and cucumber mosaic virus but not potato virus X (PVX) resulted in strong silencing suppression activity of a transgene in both leaves and roots, whereas infection by beet necrotic yellow vein virus (BNYVV) and tobacco rattle virus (TRV) showed transgene silencing suppression in roots but not in leaves. For most viruses tested, viral negative-strand RNA accumulated at a very low level in roots, compared with considerable levels of positive-strand genomic RNA. Co-inoculation of leaves with PVX and either BNYVV or TRV produced an increase in PVX negative-strand RNA and subgenomic RNA (sgRNA) accumulation in roots. The cysteine-rich proteins (CRPs) BNYVV p14 and TRV 16K showed weak silencing suppression activity in leaves. However, when either of these CRPs was expressed from a PVX vector, there was an enhancement of PVX negative-strand RNA and sgRNA accumulation in roots compared with PVX alone. Such enhancement of PVX sgRNAs was also observed by expression of CRPs of other viruses and the well-known suppressors HC-Pro and p19 but not of the potato mop-top virus p8 CRP. These results indicate that BNYVV- and TRV-encoded CRPs suppress RNA silencing more efficiently in roots than in leaves. PMID:22647371

Andika, Ida Bagus; Kondo, Hideki; Nishiguchi, Masamichi; Tamada, Tetsuo

2012-08-01

33

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

PubMed Central

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

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

2014-01-01

34

Microchannel plate streak camera  

DOEpatents

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.

Wang, C.L.

1984-09-28

35

Microchannel plate streak camera  

DOEpatents

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.

Wang, Ching L. (Livermore, CA)

1989-01-01

36

Microchannel plate streak camera  

DOEpatents

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.

Wang, C.L.

1989-03-21

37

Complex Wind Streaks  

NASA Technical Reports Server (NTRS)

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

2004-01-01

38

Visible Embryo: Primitive Streak  

NSDL National Science Digital Library

the page on early placentation and primitive streak formation from a comprehensive resource of information on human development from conception to birth, designed for both medical student and interested lay people.

Carmen Arbona (Mouseworks)

2006-09-08

39

Wheat Streak Mosaic Virus  

E-print Network

Virus First discovered in Nebraska in 1922, wheat streak mosaic virus (WSMV) remains a threat today across most of the U.S. Central Plains. WSMV affects spring wheat, barley, corn, triticale, rye and numerous other annual and perennial grasses... Virus First discovered in Nebraska in 1922, wheat streak mosaic virus (WSMV) remains a threat today across most of the U.S. Central Plains. WSMV affects spring wheat, barley, corn, triticale, rye and numerous other annual and perennial grasses...

Morgan, Gaylon

2005-01-26

40

Devil-Streaked Plain  

NASA Technical Reports Server (NTRS)

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

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

2006-01-01

41

Streak camera receiver definition study  

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

42

Black Streak of Edible Burdock Caused by Itersonilia perplexans in Japan  

Microsoft Academic Search

  Black streak disease of edible burdock (Arctium lappa L.) has been observed periodically in Hokkaido Prefecture, Japan since 1988. Symptoms appeared initially as small, dark brown\\u000a to black spots on the leaf veins and petioles. The necrotic spots developed longitudinally along the leaf veins or petioles.\\u000a Diseased leaf veins or petioles occasionally snapped off at the necrotic lesions. An Itersonilia

Harukuni HORITA; Shinji YASUOKA

2002-01-01

43

Universal Streak Camera  

NASA Astrophysics Data System (ADS)

A universal streak camera which works in synchroscan and single-shot modes with 3 plug-ins (synchroscan, fast and slow) has been developed utilizing a microchannel plate-incorporated streak tube. The synchroscan plug-in features low jitter of less than 4 ps, and high-speed sine-wave deflection from 80 to 160 MHz, achieving a limiting temporal resolution of 5 ps. The fast plug-in offers temporal resolution of better than 2 ps with triggering jitter of less than t20 ps. The slow plug-in provides longer time windows from 10 ns to 1 ms/15 mm in 16 ranges. Shutter operation down to 100 ns in duration is available with a maximum repetition rate of 1 - 10 KHz for the 3 plug-ins. An on-off ratio of more than 1:106 has been achieved by using double gate operation at photocathode and built-in microchannel plate.

Tsuchiya, Y.; Takeshima, A.; Inuzuka, E.; Suzuki, K.; Koishi, M.; Kinoshita, K.

1985-02-01

44

Dust Devil Streaks  

NASA Technical Reports Server (NTRS)

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

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

2005-01-01

45

Dust Devil Streaks  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

At first glance, the dust devil streaks observed in this THEMIS image of the martian northern plains may look similar to many other images. However, what makes this THEMIS image so interesting are the many streaks that trend over hills, mounds, and valleys. Many of the dust devil streaks previously observed occur in very flat and dusty regions. This unique image gives hints to the dynamic nature of the dust devil streak formational process.

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.

Image information: VIS instrument. Latitude 53.8, Longitude 200.9 East (159.1 West). 19 meter/pixel resolution.

2003-01-01

46

Bright Devil Streaks  

NASA Technical Reports Server (NTRS)

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

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

2005-01-01

47

Strategies for the detection of potential beet necrotic yellow vein virus genome recombinations which might arise as a result of growing A type coat protein gene-expressing sugarbeets in soil containing B type virus.  

PubMed

We have searched for beet necrotic yellow vein virus (BNYVV) populations with a recombined genome which could possibly arise when transgenic sugarbeets expressing the coat protein gene of A type BNYVV are grown in soil containing Polymyxa betae carrying B type BNYVV, in soil samples from previous field release experiments and in a greenhouse model experiment. In order to accelerate the potential evolution of virus populations with recombined genomes in the model experiment, eight successive crops of sugarbeet plantlets were grown in the same soil samples over a period of 3 years. For the sensitive detection of recombined BNYVV genomes, we used nested PCRs with sense primers that are preferentially extended on the A type BNYVV sequence in the region of the coat protein gene and antisense primers which are preferentially extended on the B type BNYVV sequence in a region downstream of the coat protein gene which is not present in the transgene. Controls with mixtures of sap from plants which were singly infected with A or with B type BNYVV only revealed that, unless proper precautions are taken, PCR-mediated recombination artifacts may readily be produced. A method was developed that is able to detect A type/B type recombinant RNA molecules up to dilutions of one to a million in pure B type RNA molecules. Inspite of this high sensitivity we failed to detect any BNYVV with a recombined genome in the transgenic plants of the model experiment or at the sites of the previous field release experiments. PMID:15070072

Koenig, R; Büttner, G

2004-02-01

48

The P25 pathogenicity factor of Beet necrotic yellow vein virus targets the sugar beet 26S proteasome involved in the induction of a hypersensitive resistance response via interaction with an F-box protein.  

PubMed

P25, a Beet necrotic yellow vein virus (BNYVV) pathogenicity factor, interacts with a sugar beet protein with high homology to Arabidopsis thaliana kelch repeat containing F-box family proteins (FBK) of unknown function in yeast. FBK are members of the Skp1-Cullin-F-box (SCF) complex that mediate protein degradation. Here, we confirm this sugar beet FBK-P25 interaction in vivo and in vitro and provide evidence for in planta interaction and similar subcellular distribution in Nicotiana tabacum leaf cells. P25 even interacts with an FBK from A. thaliana, a BNYVV nonhost. FBK functional classification was possible by demonstrating the interaction with A. thaliana orthologs of Skp1-like (ASK) genes, a member of the SCF E3 ligase. By means of a yeast two-hybrid bridging assay, a direct effect of P25 on SCF-complex formation involving ASK1 protein was demonstrated. FBK transient Agrobacterium tumefaciens-mediated expression in N. benthamiana leaves induced a hypersensitive response. The full-length F-box protein consists of one F-box domain followed by two kelch repeats, which alone were unable to interact with P25 in yeast and did not lead to cell-death induction. The results support the idea that P25 is involved in virus pathogenicity in sugar beet and suggest suppression of resistance response. PMID:22512382

Thiel, Heike; Hleibieh, Kamal; Gilmer, David; Varrelmann, Mark

2012-08-01

49

Cerberus Wind Streaks  

NASA Technical Reports Server (NTRS)

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

2002-01-01

50

Spider Veins  

MedlinePLUS

... damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkled Skin Treatments and Procedures Ambulatory Phlebectomy Blepharoplasty ... damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkled Skin Treatments and Procedures Ambulatory Phlebectomy Blepharoplasty ...

51

Eragrostis minor streak virus: an Asian streak virus in Africa  

Microsoft Academic Search

The genus Mastrevirus of the single-stranded DNA virus family Geminiviridae consists of four distinct virus lineages that have been sampled in different parts of the Old World. These include the Panicoideae-infecting African streak viruses (ten described species including the geographical outlier, Digitaria streak virus [DSV] from Vanuatu) and Australian striate mosaic viruses (three described species), the dicotyledonous-plant-infecting mastreviruses (seven described

Darren P. Martin; Daphne Linderme; Pierre Lefeuvre; Dionne N. Shepherd; Arvind Varsani

2011-01-01

52

Streak camera time calibration procedures  

NASA Technical Reports Server (NTRS)

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

Long, J.; Jackson, I.

1978-01-01

53

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. ...

54

On sublayer streaks  

NASA Astrophysics Data System (ADS)

Turbulent sublayer streaks are studied with the aid of a simplified theoretical model. In this the nonlinear activity is assumed to be intermittent and to act locally in space during a very short initial time so as to set up the initial conditions for the subsequent linear and inviscid evolution of the resulting three-dimensional flow disturbance. The mean shear flow is taken as a parallel one and a correction for the long-tern effects of viscosity is applied. A model for the initial nonlinear phase is chosen to represent the local Reynolds stresses that would be produced by a patch of local inflectional instability. The streamwise dimension of the resulting eddy is found to grow linearly with time in accordance with the algebraic instability mechanism (Landahl 1980). The associated Reynolds shear stress is expressible in a simple manner in terms of the liftup of the fluid elements and is suggestive of an algebraic-type Reynolds stress model similar to, but not identical to, that of Prandtl's (1925) mixing-length theory.

Landahl, M. T.

1990-03-01

55

Circular Scan Streak Tube Development  

NASA Technical Reports Server (NTRS)

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.

Nevin, S.

1980-01-01

56

Statistics of optimal particle streak photography  

Microsoft Academic Search

A number of statistical problems pertinent to the optimal use of particle streak photography are examined with the goal of deriving error bars and practical rules of thumb. The seeding density of particles is analyzed with the goal of maximizing the number of isolated streaks from randomly distributed particles. The number of overlapped streaks, the main source of ‘‘noise’’ in

Donald B. Altman

1991-01-01

57

Streak tube characterization for transient recording  

Microsoft Academic Search

This paper describes the methods used by EG and G Energy Measurements to characterize a streak tube. Both radiometric (QE, uniformity, gain, linearity, extinction ratio, opacity) and resolution (static, spatial, and temporal) tests are covered. The significance of these measurements with respect to streak camera applications is discussed. The results of the measurements on a streak tube designed and built

T. B. Jennings; R. W. Olsen

1987-01-01

58

Gated SIT vidicon streak tube  

SciTech Connect

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-change 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 greater than or equal to10/sup 3/ are achieved with only 10 KV accelerating voltage. This is compared with much lower gains (approx.50) at much higher voltages (approx.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 (approx.30 lp/mm), variable scan formats, and high speed electrostatic deflection (250 mm/sup 2/ 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 Sb/sub 2/S/sub 3/ FPS vidicons. Sweep sensitivity, shutter ratio, and record lengths for nanosecond duration (20 to 200 ns) streak applications are discussed.

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

1985-01-01

59

Varicose veins  

PubMed Central

Introduction Varicose veins are caused by poorly functioning valves in the veins, and decreased elasticity of the vein wall, allowing pooling of blood within the veins, and their subsequent enlargement. Varicose veins affect up to 40% of adults, and are more common in obese people, and in women who have had more than two pregnancies. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments in adults with varicose veins? We searched: Medline, Embase, The Cochrane Library and other important databases up to January 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 39 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression stockings, endovenous laser, injection sclerotherapy, radiofrequency ablation, self-help (advice, avoidance of tight clothing, diet, elevation of legs, exercise), and surgery (stripping, avulsion, powered phlebectomy). PMID:21477400

2011-01-01

60

Dark streaks on talus slopes, Mars  

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

61

Subterranean clover red leaf virus and bean yellow mosaic virus in alsike clover  

Microsoft Academic Search

Subterranean clover red leaf virus (SCRLV) and bean yellow mosaic virus (BYMV) were isolated from alsike clover (Trifolium hybridum L.) grown in experimental plots on the Canterbury Plains. SCRLV caused reddening of older leaves, and BYMV caused yellowing and streaking of the leaves of infected plants. Some plants were infected by both viruses. A survey in the mid-altitude zone (50D-1000

J. W. Ashby

1976-01-01

62

Notes on the IMACON 500 streak camera system  

SciTech Connect

The notes provided are intended to supplement the instruction manual for the IMACON 500 streak camera system. The notes cover the streak analyzer, instructions for timing the streak camera, and calibration. (LEW)

Clendenin, J.E.

1985-01-31

63

Statistics of optimal particle streak photography  

Microsoft Academic Search

To derive error bars and practical rules of thumb, statistical problems of optimal particle streak photography (PSP) have been examined. Four practical problems are discussed, including the seeding density of particles necessary for maximizing the number of isolated streaks from randomly distributed particles, estimation of the mean of an arbitrary velocity field with randomly placed noise-free measurements, determination of the

Donald B. Altman

1991-01-01

64

Laminar streaks with spanwise wall forcing  

NASA Astrophysics Data System (ADS)

The influence of steady sinusoidal oscillations of spanwise wall velocity on the Klebanoff modes, i.e. unsteady streaky fluctuations induced by free-stream turbulence in the pre-transitional Blasius boundary layer, is investigated numerically. The wall motion induces a spanwise boundary layer which grows downstream as x1/6 and has an asymptotic analytical solution at large downstream distances. While the forcing has no effect on the initial growth of the streaks, their intensity eventually increases or decreases substantially depending on the relative magnitude between the forcing wavelength and the characteristic length scales of the streaks. The wall actuation enhances the streak intensity if the streak spanwise length scale is much larger than the Blasius boundary layer thickness. The streak energy is instead attenuated when the spanwise viscous diffusion effects play a key role. Wall pressure fluctuations may also be significantly damped in this case. The Klebanoff modes generated by full-spectrum free-stream turbulence are predicted to be attenuated by the wall motion. The asymptotic scaling analysis reveals that there exists an optimal forcing wavelength for full-spectrum streak attenuation as long as the spanwise length scales of the dominant streaks are as large as or smaller than the Blasius boundary layer thickness, a common scenario encountered in experiments. The optimal forcing wavelength is found to be comparable with the streak streamwise length scale. As the amplitude of the wall forcing increases, the reduction of streak intensity grows monotonically. The streaks are completely suppressed in the limit of large amplitude.

Ricco, Pierre

2011-06-01

65

Electro-optic phase grating streak spectrometer  

NASA Astrophysics Data System (ADS)

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. Since 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.

Goldin, Fletcher

2012-10-01

66

Atomic and molecular phases through attosecond streaking  

SciTech Connect

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

Baggesen, Jan Conrad; Madsen, Lars Bojer [Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)

2011-02-15

67

Yellow Fever Vaccine  

MedlinePLUS

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

68

Yellow Fever  

Microsoft Academic Search

\\u000a In 1951, Max Theiler (Fig. 10.1), a Rockefeller Foundation scientist, became the only person to be awarded the Nobel Prize\\u000a in Medicine and Physiology for the development of a virus vaccine (Norrby 2007). His live, attenuated 17D vaccine was not\\u000a the first yellow fever vaccine to be tested in humans, but it was by far the most successful one. More

Thomas P. Monath

69

Large Reynolds number streak description using RNS  

NASA Astrophysics Data System (ADS)

It has been recently shown [Choi, Nature, April 06 - Cossu et al., PRL, February 06] that the inclusion of 3D streaky structures in the boundary layer can make it remain laminar longer than the purely 2D Blasius flow. We compute the development of 3D streaks in the boundary layer over a flat plate using the so-called Reduced Navier Stokes equations (RNS). The RNS are a boundary layer like formulation, which is derived from the Navier-Stokes equations making use of the fact that in the large Re limit two very different spatial scales are present: one long (streamwise direction) and two short (spanwise and wall-normal direction). The resulting RNS are a nonlinear, parabolic, Re independent system that describes the streak structure in the large Re limit. The RNS streak computations are also much more less CPU costly than DNS for high Re, and they don't have the numerical problems that the PSE formulation exhibits (divergence of the results for small ?x, or blow-up of the solution when the amplitude of the deviation from Blasius is not small). In this work we comment the details of the numerical integration of the RNS, and we present some comparisons of the RNS results with the linear computations of streak development together with some fully nonlinear computations of streak evolution.

Martin, Juan; Martel, Carlos

2009-11-01

70

Travelers' Health: Yellow Fever  

MedlinePLUS

... the Geographic Risk of Yellow Fever. Map 3-17. Yellow fever vaccine recommendations in the Americas 1 ... and yellow fever vaccination. Lancet. 2004 Sep 11–17;364(9438):936. Cavalcanti DP, Salomao MA, Lopez- ...

71

Deep Vein versus Pseudo Deep Vein Thrombosis  

PubMed Central

An acutely swollen, painful calf is usually caused by deep vein thrombosis or pseudo deep vein thrombosis; however, the differential diagnosis and management of these 2 entities can prove difficult and even hazardous unless a careful, systematic approach is used. This article describes the use of 2 invasive techniques (ascending venography and arthrography) and several noninvasive methods (magnetic resonance imaging, computerized axial tomography, and non-Doppler ultrasound) to differentiate between deep vein thrombosis and pseudo deep vein thrombosis. The author discusses a practical, cost-effective approach to diagnosing and managing the acutely swollen, painful calf. (Texas Heart Institute Journal 1989;16:280-6) Images PMID:15227382

Ansari, Azam

1989-01-01

72

Frost streaks in the south polar cap of Mars  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

73

The first satellite laser echoes recorded on the streak camera  

NASA Technical Reports Server (NTRS)

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

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

1993-01-01

74

Perception of Randomness: On the Time of Streaks  

ERIC Educational Resources Information Center

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

Sun, Yanlong; Wang, Hongbin

2010-01-01

75

Optociliary veins and central retinal vein occlusion  

Microsoft Academic Search

In a follow up of 94 patients with central retinal vein occlusion (CRVO) whose onset had taken place less than 1 year earlier, optociliary veins (OCVs) were found in 7.4% at first examination. Among the 79 eyes in which the fundus of the eye was very visible after a follow up of more than 1 year OCVs were found in

G Giuffrè; C Palumbo; G Randazzo-Papa

1993-01-01

76

Streaks Of Colored Water Indicate Surface Airflows  

NASA Technical Reports Server (NTRS)

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

Wilcox, Floyd J., Jr.

1994-01-01

77

What Are Varicose Veins?  

MedlinePLUS

... Gets Them? Varicose veins are more common in women, and people are more likely to get them as they get older. These veins can be genetic (say: juh-NEH-tik). That means that if your mom or your sister ... veins. Sometimes women who are pregnant get them, too. If someone ...

78

Wind Streaks on Venus: Clues to Atmospheric Circulation  

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

79

How accurate is the attosecond streak camera?  

PubMed

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

Ivanov, Misha; Smirnova, Olga

2011-11-18

80

Streak breakdown instability in pipe Poiseuille flow  

Microsoft Academic Search

This work is devoted to the study of the stability of Hagen–Poiseuille flow or pipe flow. The analysis is focused on the streak breakdown process by which two-dimensional streamwise-independent finite amplitude perturbations transiently modulate the basic flow leading to a profile that contains saddle points and is linearly unstable with respect to very small streamwise-dependent perturbations. This mechanism is one

A´lvaro Meseguer

2003-01-01

81

Streak breakdown instability in pipe Poiseuille flow  

Microsoft Academic Search

This work is devoted to the study of the stability of Hagen-Poiseuille flow or pipe flow. The analysis is focused on the streak breakdown process by which two-dimensional streamwise-independent finite amplitude perturbations transiently modulate the basic flow leading to a profile that contains saddle points and is linearly unstable with respect to very small streamwise-dependent perturbations. This mechanism is one

Álvaro Meseguer

2003-01-01

82

Vein of Galen Aneurysms  

PubMed Central

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

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

2001-01-01

83

Preventing Deep Vein Thrombosis  

MedlinePLUS

... birth control methods that contain estrogen or hormone therapy for menopause symptoms • Certain illnesses, including heart failure, inflammatory bowel disease, and some kidney disorders • Obesity • Smoking • Varicose veins • ...

84

Brassicaceae (Mustard family) Yellow rocket  

E-print Network

Brassicaceae (Mustard family) Yellow rocket Barbarea vulgaris R. Br. Life cycle Erect winter annual, gradually becoming smaller toward the top. Yellow rocket seedling. Yellow rocket flowers. Back in cross-section. Reproduction Seeds. Yellow rocket lower leaf. Yellow rocket rosette. Yellow rocket

85

X-ray streak crystal spectography  

SciTech Connect

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

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

1983-07-01

86

Radar-visible wind streaks in the Altiplano of Bolivia  

NASA Technical Reports Server (NTRS)

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.

Greeley, R.; Christensen, P.

1984-01-01

87

RESEARCH ARTICLE Bichromatic particle streak velocimetry bPSV  

E-print Network

RESEARCH ARTICLE Bichromatic particle streak velocimetry bPSV Interfacial, volumetric three-component velocimetry using a single camera Bjo¨rn Voss · Julian Stapf · Andre´ Berthe · Christoph S. Garbe Received: 20 three-component (3D3C) interfacial flow measurement. It is based on the particle streak velocimetry

Garbe, Christoph S.

88

Fluid dynamical implications of anastomosing slope streaks on Mars  

Microsoft Academic Search

The Mars Global Surveyor mission has imaged slope streaks, some of which have formed in periods as short as 109 days. These features are one of the most currently active surface processes on Mars. Some slope streaks have flow-like morphologic characteristics, which include anastomosing patterns influenced by small topographic barriers. In order to understand what processes gave rise to these

Hideaki Miyamoto; James M. Dohm; Ross A. Beyer; Victor R. Baker

2004-01-01

89

Streak breakdown instability in pipe Poiseuille flow  

NASA Astrophysics Data System (ADS)

This work is devoted to the study of the stability of Hagen-Poiseuille flow or pipe flow. The analysis is focused on the streak breakdown process by which two-dimensional streamwise-independent finite amplitude perturbations transiently modulate the basic flow leading to a profile that contains saddle points and is linearly unstable with respect to very small streamwise-dependent perturbations. This mechanism is one possible route of transition to turbulence in subcritical shear flows. The exploration is carried out for initial disturbances of different finite amplitudes and axial and azimuthal periodicity. This study covers a wide range of Reynolds numbers and the double threshold curve obtained for transition is consistent with experimental observations.

Meseguer, Álvaro

2003-05-01

90

The study of streak camera dynamic distortion  

NASA Astrophysics Data System (ADS)

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

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

2012-10-01

91

Inducible Resistance to Maize Streak Virus  

PubMed Central

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

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

2014-01-01

92

High performance imaging streak camera for the National Ignition Facility  

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

93

High performance imaging streak camera for the National Ignition Facility.  

PubMed

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

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

2012-12-01

94

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

SciTech Connect

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

Not Available

1993-11-20

95

Workshop on standards for photonic streak camera characterization  

SciTech Connect

A summary paper proposing standardization of definitions and parameter measurements related to photonic streak cameras was generated at the 16th International Congress of High Speed Photography and Photonics at Strasborg, France (August 1984). An international committee appointed by the general Workshop on Picosecond Streak Cameras met and discussed the areas appropriate for standardization and proposed specific definitions, measurements and complementary parameter sets to be used in characterizing photonic streak cameras. These proposals were compiled into a summary paper by the committee co-chairmen, Noel Fleurot (CEA-Limeil) and Gary L. Stradling (Los Alamos National Laboratory), with the intent that it be distributed to interested streak camera users and manufacturers and that appropriate improvements and additions be solicited.

Stradling, G.L.

1985-01-01

96

Note: X-ray streak camera sweep speed calibration.  

PubMed

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

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

2010-05-01

97

Attosecond streaking of photoelectron emission from disordered solids  

E-print Network

Attosecond streaking of photoelectrons emitted by extreme ultraviolet light has begun to reveal how electrons behave during their transport within simple crystalline solids. Many sample types within nanoplasmonics, thin-film physics, and semiconductor physics, however, do not have a simple single crystal structure. The electron dynamics which underpin the optical response of plasmonic nanostructures and wide-bandgap semiconductors happen on an attosecond timescale. Measuring these dynamics using attosecond streaking will enable such systems to be specially tailored for applications in areas such as ultrafast opto-electronics. We show that streaking can be extended to this very general type of sample by presenting streaking measurements on an amorphous film of the wide-bandgap semiconductor tungsten trioxide, and on polycrystalline gold, a material that forms the basis of many nanoplasmonic devices. Our measurements reveal the near-field temporal structure at the sample surface, and photoelectron wavepacket te...

Okell, W A; Fabris, D; Arrell, C A; Hengster, J; Ibrahimkutty, S; Seiler, A; Barthelmess, M; Stankov, S; Lei, D Y; Sonnefraud, Y; Rahmani, M; Uphues, Th; Maier, S A; Marangos, J P; Tisch, J W G

2014-01-01

98

Tests for Wet Mechanism of Slope Streaks Formation on Mars.  

NASA Astrophysics Data System (ADS)

Slope streaks are forming in some equatorial regions on Mars. They have been mostly interpreted as a result of dry mass wasting of dust. Recently a striking morphological similarity with wet slope streaks in the Antarctic Dry Valleys has been demonstrated. Physical conditions on Mars do not allow the same mechanism. We propose a "wet" mechanism on Mars, which inherits the main feature of the Antarctic slope streaks responsible for their distinctive planforms, namely, shallow subsurface percolation of liquid above the ice table. This mechanism assumes some ice in the shallow subsurface, which had been emplaced under previous wetter climate conditions and currently is undergoing slow desiccation. This icy soil is overlaid by a layer highly enriched in chlorides. On top of this layer, there is a thin layer of dry fine dust. During the warm season, droplets of highly concentrated brines are formed in the salty layer. Sometimes at some places, the droplets coalesce; the liquid percolates downhill, wicks up through the dust layer and dries up. This alters the uppermost dust layer structure, which affects the surface albedo and observable as a dark streak. Further gradual changes of this new surface structure lead to slow brightening of the streak and final fading away. Such a mechanism is at the margin of physical possibility and consistency with observational constraints. Prospective observational tests for "wet" mechanism: (1) Spectral signature of hydrated chlorides in fresh streaks, would make "wet" hypothesis much more probable. (2) Gentle slope of slope streaks, especially of their uppermost parts would strongly favor "wet" mechanism. (3) Observation of slope streak formation during cold seasons, when the day-average surface temperature is below 190 K would reject "wet" mechanism. (4) Observation of a slope streak in the process of formation (a streak that lengthens from earlier to later image) would almost prove "wet" mechanism, at least, almost reject dry avalanche scenario. (5) Absence of a shallow high-thermal-inertia layer would be inconsistent with a "wet" scenario. (6) Geomorphologic observations supporting subsurface ice in the slope streak regions would favor the "wet" mechanism.

Kreslavsky, M.; Head, J.

2007-12-01

99

Shuttle radar images of wind streaks in the Altiplano, Bolivia  

Microsoft Academic Search

Shuttle imaging radar (SIR-A) coverage across Bolivia shows the major physiographic provinces, including the Andean Altiplano. The Altiplano contains a variety of eolian features, many of which are visible as radar-dark, radar-mottled, and radar-bright streaks aligned parallel to the prevailing winds. The streaks form downwind from hills and are as much as 15 km long and 800 m wide. Dark

Ronald Greeley; Philip Christensen; Raul Carrasco

1989-01-01

100

Streak image denoising and segmentation using adaptive Gaussian guided filter.  

PubMed

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

Jiang, Zhuocheng; Guo, Baoping

2014-09-10

101

[Sclerosis in varicose veins].  

PubMed

The authors report their experience in the sclerotherapy of varicose veins. They have used the technique of French school: with the patient half sitting, direct puncture not far from the gulf of saphena without tourniquet, on a weekly basis. PMID:9835187

Perilli, G; Scioscia, P; Ferretti, L

1998-10-01

102

Yellow Legged Frog  

USGS Multimedia Gallery

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

2009-07-23

103

Sublingual vein injection in rodents  

Microsoft Academic Search

SUMMARY A simple and rapid technique for intravenous IllJection into the sub- lingual veins of common laboratory rodents is described. No prior pre- paration other than light anaesthesia is required and repeated injections can be made into the same vein. 35 The major problem associated with intravenous administration in common laboratory rodents is the inaccessibility of the veins. In most

H. B. Waynforth; R. Parkin

1969-01-01

104

Extrahepatic portal vein aneurysm.  

PubMed

Portal vein aneurysms (PVAs) are usually incidental on imaging and asymptomatic. If it is symptomatic or associated with a pathologic finding, a treatment is recommended. We report a case of a 75-year-old Caucasian man presenting with symptomatic and size-increasing portosplenomesenteric aneurysms. Interventional radiology was not indicated because of the large size. A surgical approach was chosen for the patient. Surgical technique consists of an aneurysmorrhaphy in the first time and in the second time, a Goretex prosthesis placement involving the vein. Early complication was treated with a radiologic approach. Six months after surgery, patient had no more symptoms. PVA management remains a surgical challenge for surgeon, for timing and type of treatment. PMID:24456867

Levi Sandri, Giovanni Battista; Sulpice, Laurent; Rayar, Michel; Bosquet, Elise; Boudjema, Karim; Meunier, Bernard

2014-07-01

105

Portal vein thrombosis  

Microsoft Academic Search

Opinion statement  Portal vein thrombosis (PVT) can be a difficult clinical problem to assess and manage. A high index of suspicion is needed\\u000a for a PVT diagnosis given the subtle presentation and potentially serious long-term complications. It should be considered\\u000a a clue to the presence of one or several underlying disorders, including prothrombotic disorders, whether or not a local precipitating\\u000a factor

Hector Rodriguez-Luna; Hugo E. Vargas

2007-01-01

106

Unsteady analysis of hot streak migration in a turbine stage  

NASA Technical Reports Server (NTRS)

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'.

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

1990-01-01

107

Hitting Is Contagious in Baseball: Evidence from Long Hitting Streaks  

PubMed Central

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

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

2012-01-01

108

Characteristics of an ultrafast x-ray streak camera  

SciTech Connect

The detection and temporal dispersion of the x-rays using x-ray streak cameras has been limited to a resolution of 2 ps, primarily due to the transit time dispersion of the electrons between the photocathode and the acceleration grid. The transit time spread of the electrons traveling from the photocathode to the acceleration grid is inversely proportional to the accelerating field. By increasing the field by a factor of 7, we have minimized the effects of transit time dispersion in the photocathode/accelerating grid region and produce an x-ray streak camera with sub-picosecond temporal resolution ({approximately}900 fs). The streak camera has been calibrated using a Michelson interferometer and 100 fs, 400 nm laser light. Time resolved x-ray data is shown from an aluminum target heated at 10{sup 18} W/cm{sup 2} with a 100 fs, 400 nm laser .

Shepherd, R.; Booth, R.; Price, D. [and others

1994-06-01

109

A time-resolved image sensor for tubeless streak cameras  

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

110

Presumed ocular histoplasmosis syndrome and linear streak lesions.  

PubMed Central

Five cases of subretinal neovascular membranes in the macula associated with punched out chorioretinal scars and linear streaks were seen in five Dutch patients. Clinically the fundus lesions are consistent with those of presumed ocular histoplasmosis syndrome (POHS) seen in the United States of America. Cutaneous serological testing for histoplasmin reactivity was negative in the three patients tested. Of special interest is the presence of linear streaks in association with POHS. They have not been previously described in patients from Europe with this syndrome. Images PMID:2757993

Bottoni, F G; Deutman, A F; Aandekerk, A L

1989-01-01

111

Fluorescence lifetime imaging microscopy using a streak camera  

NASA Astrophysics Data System (ADS)

We present the development of a fluorescence lifetime imaging microscopy system using a streak camera (SC-FLIM), which uses ultrafast infrared laser for multiphoton excitation and a streak camera for lifetime measurement. A pair of galvo mirrors are employed to accomplish quick time-resolved scanning on a line and 2D fluorescence lifetime imaging. The SC-FLIM system was calibrated using an F-P etalon and several standard fluorescent dyes, and was also used to perform fluorescence lifetime imaging of fluorescent microspheres and a prepared plant stem slide.

Liu, Lixin; Li, Yahui; Sun, Luogeng; Li, Heng; Peng, Xiao; Qu, Junle

2014-02-01

112

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

NASA Astrophysics Data System (ADS)

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.

Roback, Richard J.; Dring, Robert P.

1992-06-01

113

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

NASA Technical Reports Server (NTRS)

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.

Roback, Richard J.; Dring, Robert P.

1992-01-01

114

Mass movement within a slope streak on Mars Cynthia B. Phillips,1  

E-print Network

Mass movement within a slope streak on Mars Cynthia B. Phillips,1 Devon M. Burr,1 and Ross A. Beyer 2007. [1] Slope streaks on Mars represent a currently active geological process. Various theories streak on Mars, Geophys. Res. Lett., 34, L21202, doi:10.1029/2007GL031577. 1. Introduction [2] Slope

Perfect, Ed

115

Particle streak velocimetry and CH laser-induced fluorescence diagnostics in strained, premixed,  

E-print Network

Particle streak velocimetry and CH laser-induced fluorescence diagnostics in strained, premixed, 91125 Abstract We present the use of simultaneous Particle Streak Velocimetry (PSV) and CH Planar Laser Streak Velocimetry (PSV) [1­3], a tech- nique similar to particle tracking velocimetry [4], is used

Barr, Al

116

Media Online Yellow Pages  

NSDL National Science Digital Library

The Media Online Yellow Pages is another good place (along with the Big List and Newslink mentioned last week) to find media sources on the Internet. Does not appear to be searchable but the index is well-organized for browsing.

117

Photo yellowing of human hair  

Microsoft Academic Search

In general, human hair is claimed to turn yellower after sun exposure. This is particularly affirmed for white hair. However, quantitative data relating yellowness to hair type and to the radiation wavelength are missing. This work shows results of the effect of full or UVB-filtered radiation of a mercury vapor or a xenon-arc lamp on the yellowness of virgin white,

A. C. S. Nogueira; M. Richena; L. E. Dicelio; I. Joekes

2007-01-01

118

Microrobotic Streak Seeding For Protein Crystal Growth CUCS04104  

E-print Network

Microrobotic Streak Seeding For Protein Crystal Growth CUCS­041­04 Atanas Georgiev 1 Peter Allen 1 that consists of picking individual protein crystal from growth solution the purpose X­ray data collection) transferred protein solution that optimized their growth. building high­throughput protein crystal production

119

Reliable and repeatable characterization of optical streak cameras.  

PubMed

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

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

2008-10-01

120

The Cause of Streaks upon Lath and Plaster Walls  

Microsoft Academic Search

IN reply to Mr. Thomas D. Cope's letter in NATURE of January 21, it may be stated that he is correct in supposing that the best explanation of the streaks on the plaster he refers to is that they are due to the hot-air molecules driving the dust particles into contact with the plaster, and the colder the plaster the

John Aitken

1915-01-01

121

JAMA Patient Page: Treatment of Varicose Veins  

MedlinePLUS

... removal of varicose veins just below the skin’s surface. • Sclerotherapy —a solution is injected into the vein causing it to scar down and visibly fade. This therapy is recommended for telangiectasias, reticular veins, or small ...

122

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

PubMed

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

Vemana, K; Jain, R K

2010-10-01

123

[Yellow fever: new recommendations].  

PubMed

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

Rochat, L; Genton, B

2014-05-01

124

Vein matching using artificial neural network in vein authentication systems  

NASA Astrophysics Data System (ADS)

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.

Noori Hoshyar, Azadeh; Sulaiman, Riza

2011-10-01

125

Streaked x-ray microscopy of laser-fusion targets  

SciTech Connect

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.

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

126

Megahertz streak-mode Fourier domain optical coherence tomography  

NASA Astrophysics Data System (ADS)

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

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

2011-06-01

127

rf streak camera based ultrafast relativistic electron diffraction.  

PubMed

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

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

2009-01-01

128

Development of streak camera with anisotropic focusing electron optical system  

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

129

Detection of episomal banana streak badnavirus by IC-PCR  

Microsoft Academic Search

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

Glyn Harper; Ganesh Dahal; George Thottappilly; R. Hull

1999-01-01

130

Attosecond streaking experiments on atoms: quantum theory versus simple model  

E-print Network

A new theoretical approach to the description of the attosecond streaking measurements of atomic photoionization is presented. It is a fully quantum mechanical description based on numerical solving of the time-dependent Schroedinger equation which includes the atomic field as well as the fields of the XUV and IR pulses. Also a simple semiempirical description based on sudden approximation is suggested which agrees very well with the exact solution.

Kazansky, A K

2006-01-01

131

Serum bone GLA protein in streak gonad syndrome  

Microsoft Academic Search

Summary  Osteoporosis is one of the most common complications of streak gonad syndrome (SGS), however its pathogenesis is still unclear.\\u000a Bone Gla protein (BGP) has been found to be a serum marker of bone turnover in various metabolic disease states. In the present\\u000a study serum BGP and alkaline phosphatase (AP) were measured in 13 osteoporotic patients with SGS and in 56

János Zséli; Péter Bösze; Péter Lakatos; Péter Vargha; Gábor Tarján; Éva Kollin; Csaba Horváth; János László; István Holló

1991-01-01

132

Design of microcontroller based system for automation of streak camera.  

PubMed

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

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

2010-08-01

133

Streaking at high energies with electrons and positrons  

SciTech Connect

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

Ipp, Andreas; Evers, Joerg; Keitel, Christoph H.; Hatsagortsyan, Karen Z. [Institut fuer Theoretische Physik, Technische Universitaet Wien, 1040 Vienna (Austria); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

2012-07-09

134

Slope streaks on Mars: A new “wet” mechanism  

NASA Astrophysics Data System (ADS)

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

Kreslavsky, Mikhail A.; Head, James W.

2009-06-01

135

Perception of randomness: On the time of streaks.  

PubMed

People tend to think that streaks in random sequential events are rare and remarkable. When they actually encounter streaks, they tend to consider the underlying process as non-random. The present paper examines the time of pattern occurrences in sequences of Bernoulli trials, and shows that among all patterns of the same length, a streak is the most delayed pattern for its first occurrence. It is argued that when time is of essence, how often a pattern is to occur (mean time, or, frequency) and when a pattern is to first occur (waiting time) are different questions and bear different psychological relevance. The waiting time statistics may provide a quantitative measure to the psychological distance when people are expecting a probabilistic event, and such measure is consistent with both of the representativeness and availability heuristics in people's perception of randomness. We discuss some of the recent empirical findings and suggest that people's judgment and generation of random sequences may be guided by their actual experiences of the waiting time statistics. PMID:20728080

Sun, Yanlong; Wang, Hongbin

2010-12-01

136

Design of microcontroller based system for automation of streak camera  

SciTech Connect

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.

Joshi, M. J.; Upadhyay, J.; Deshpande, P. P.; Sharma, M. L.; Navathe, C. P. [Laser Electronics Support Division, RRCAT, Indore 452013 (India)

2010-08-15

137

Varicose Veins and Venous Insufficiency  

MedlinePLUS

... flowing toward the heart—against the force of gravity. When the valves do not perform their function, ... the vein, an interventional radiologist inserts a thin tube known as a catheter, about the size of ...

138

Inflammation in Retinal Vein Occlusion  

PubMed Central

Retinal vein occlusion is a common, vision-threatening vascular disorder. The role of inflammation in the pathogenesis and clinical consequences of retinal vein occlusion is a topic of growing interest. It has long been recognized that systemic inflammatory disorders, such as autoimmune disease, are a significant risk factor for this condition. A number of more recent laboratory and clinical studies have begun to elucidate the role inflammation may play in the molecular pathways responsible for the vision-impairing consequences of retinal vein occlusion, such as macular edema. This improved understanding of the role of inflammation in retinal vein occlusion has allowed the development of new treatments for the disorder, with additional therapeutic targets and strategies to be identified as our understanding of the topic increases. PMID:23653882

Deobhakta, Avnish; Chang, Louis K.

2013-01-01

139

Benefits of Endoscopic Vein Harvesting  

Microsoft Academic Search

.   The purpose of this study was to evaluate and compare the benefits of endoscopic saphenous vein harvesting (EVH) with the\\u000a traditional incision technique (TIT) for coronary artery bypass grafting (CABG) in respect to the technical procedure and\\u000a clinical outcome. In a prospective nonrandomized, case-matched study the greater saphenous vein was harvested for CABG in\\u000a 22 patients using the endoscopic

Bettina Marty; Ludwig Karl von Segesser; Piergiorgio Tozzi; Juan Guzmann; Philippe Frascarolo; Xavier Muller; Daniel Hayoz

2000-01-01

140

Streak camera based SLR receiver for two color atmospheric measurements  

NASA Technical Reports Server (NTRS)

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

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

1993-01-01

141

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

NASA Technical Reports Server (NTRS)

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.

Roback, Richard J.; Dring, Robert P.

1992-01-01

142

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

PubMed

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

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

2014-06-01

143

Defrosting Polar Dunes--Dark Spots and Wind Streaks  

NASA Technical Reports Server (NTRS)

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

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

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

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

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

1999-01-01

144

Streaks of Aftershocks Following the 2004 Sumatra-Andaman Earthquake  

NASA Astrophysics Data System (ADS)

Five years after the devastating 26 December, 2004 M 9.3 Sumatra-Andaman earthquake, regional and global seismic networks have recorded tens of thousands of aftershocks. We use bulletin data from the International Seismological Centre (ISC) and the National Earthquake Information Center (NEIC), and waveforms from IRIS, to relocate more than 20,000 hypocenters between 1964 and 2008 using teleseimic cross-correlation and double-difference methods. Relative location uncertainties of a few km or less allow for detailed analysis of the seismogenic faults activated as a result of the massive stress changes associated with the mega-thrust event. We focus our interest on an area of intense aftershock activity off-shore Banda Aceh in northern Sumatra, where the relocated epicenters reveal a pattern of northeast oriented streaks. The two most prominent streaks are ~70 km long with widths of only a few km. Some sections of the streaks are formed by what appear to be small, NNE striking sub-streaks. Hypocenter depths indicate that the events locate both on the plate interface and in the overriding Sunda plate, within a ~20 km wide band overlying the plate interface. Events on the plate interface indicate that the slab dip changes from ~20° to ~30° at around 50 km depth. Locations of the larger events in the overriding plate indicate an extension of the steeper dipping mega thrust fault to the surface, imaging what appears to be a major splay fault that reaches the surface somewhere near the western edge of the Aceh basin. Additional secondary splay faults, which branch off the plate interface at shallower depths, may explain the diffuse distribution of smaller events in the overriding plate, although their relative locations are less well constrained. Focal mechanisms support the relocation results. They show a narrowing range of fault dips with increasing distance from the trench. Specifically, they show reverse faulting on ~30° dipping faults above the shallow (20°) dipping plate interface. The observation of active splay faults associated with the mega thrust event is consistent with co- and post-seismic motion data, and may have significant implications on the generation and size of the tsunami that caused 300,000 deaths.

Waldhauser, F.; Schaff, D. P.; Engdahl, E. R.; Diehl, T.

2009-12-01

145

Ultrashort pulse characterization with a terahertz streak camera.  

PubMed

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

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

2011-11-15

146

Agrobacterium-mediated infectivity of cloned digitaria streak virus DNA.  

PubMed

A monomeric clone of double-stranded DNA synthesized in vitro DNA of the geminivirus Digitaria streak (DSV) was subcloned as a tandem dimeric unit into a binary vector of Agrobacterium tumefaciens, creating a plasmid pDS2. Inoculation of digitaria sanguinalis with A. tumefaciens carrying pDS2 resulted in viral infection. The symptoms, virus particles, and DNA forms obtained were indistinguishable from those of a natural DSV infection of D. sanguinalis. Inoculations have also induced infections in Zea mays and Avena sativa. The sequence of the Agrobacterium-mediated infectious clone of DSV has been determined. PMID:3341112

Donson, J; Gunn, H V; Woolston, C J; Pinner, M S; Boulton, M I; Mullineaux, P M; Davies, J W

1988-01-01

147

ETIOLOGY OF YELLOW FEVER  

PubMed Central

By the employment of methods designed to promote the growth both of aerobic and anaerobic organisms, particularly those belonging to the class of spirochetes, it was possible to obtain a pure culture of a delicate organism, the morphological features of which place it in the genus Leptospira. On three occasions, that is, from three out of eleven cases of yellow fever, the organism was directly cultivated. These three strains were found to induce the characteristic symptoms and lesions when tested on guinea pigs. The organism was designated Leptospira icteroides. Leptospira icteroides was also obtained in pure culture from the blood of guinea pigs which succumbed to infection after being inoculated with the blood or organ emulsions from patients suffering from yellow fever. These cultures also proved to be virulent when tested on susceptible animals. The morphological characteristics and certain biological properties of the organism were considered in detail. It is invisible under translucent illumination and is difficult to stain by most aniline dyes. It is highly sensitive to the presence of bacteria and is rapidly destroyed in a medium in which certain other organisms are present. The presence of blood serum (man, sheep, horse, rabbit, etc.) seems to be essential for its growth. It grows well at a temperature of about 25–26°C. and more quickly at 37°C., though at the latter temperature it dies out within a few weeks. At 25°C. under favorable conditions and in suitable culture media it remains viable for several months without losing its virulence. Leptospira icteroides multiplies by transverse division. The virulence attained by some strains was such that 0.00001 cc. of a culture could induce typical fatal infection in guinea pigs. There exists a considerable variation among guinea pigs in their susceptibility to Leptospira icteroides. The organism is killed within 10 minutes at a temperature of 55°C. and is also destroyed by complete desiccation or freezing and thawing. Bile and bile salts dissolve it in certain concentrations, but not saponin. Leptospira icteroides passes through the pores of Berkefeld filters V and N, and there is a possibility of its having a granular phase of life under certain conditions. PMID:19868342

Noguchi, Hideyo

1919-01-01

148

Microprocessor-controlled, wide-range streak camera  

SciTech Connect

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.

Amy E. Lewis, Craig Hollabaugh

2006-09-01

149

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

SciTech Connect

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)

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

1987-01-30

150

A possible role for chemotaxis in primitive streak formation  

NASA Astrophysics Data System (ADS)

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

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

2010-03-01

151

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

PubMed

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

Gray, Rob; Allsop, Jonathan

2013-08-01

152

Microprocessor-controlled wide-range streak camera  

NASA Astrophysics Data System (ADS)

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.

Lewis, Amy E.; Hollabaugh, Craig

2006-08-01

153

A Monte Carlo Approach to Joe DiMaggio and Streaks in Baseball  

Microsoft Academic Search

We examine Joe DiMaggio's 56-game hitting streak and look at its likelihood, using a number of simple models. And it turns out that, contrary to many people's expectations, an extreme streak, while unlikely in any given year, is not unlikely to have occurred about once within the history of baseball. Surprisingly, however, such a record should have occurred far earlier

Samuel Arbesman; S. H. Strogatz

2008-01-01

154

Yellow Fever Virus Infection  

PubMed Central

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

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

1971-01-01

155

Turnip Yellow Mosaic Virus  

NASA Technical Reports Server (NTRS)

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

2000-01-01

156

Characterization of X-ray streak cameras for use on Nova  

SciTech Connect

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

Kalantar, D.H.; Bell, P.M.; Costa, R.L.; Hammel, B.A.; Landen, O.L.; Orzechowski, T.J. [Lawrence Livermore National Lab., CA (United States); Hares, J.D.; Dymoke-Bradshaw, A.K.L. [Kentech Instruments Ltd., Didcot (United Kingdom)

1996-09-01

157

Space charge effects in the axis-photonique PX-1 x-ray streak camera  

NASA Astrophysics Data System (ADS)

The Axis-Photonique PX1 fast X-ray streak camera records the temporal structure of events with picosecond accuracy. Using a potassium iodide photocathode the streak camera has been characterised for the effects of space charge. In a recent grazing incidence pumping X-ray laser experiment the streak camera was coupled to the output of a flat field spectrometer to observe first order diffraction. The second order was observed using a CCD camera. In this paper data is presented from this experiment comparing the brightness of the X-ray laser emission with the dispersion of the streaked image both temporally and spectrally (non temporal direction). Consequently measurements of the dynamic range of the streak camera are made. The results are compared with data from previous experiments.

Edwards, M. H.; Booth, N.; Zhai, Z.; Tallents, G. J.; Dzelzainis, T.; Lewis, C. L. S.; Foster, P.; Streeter, M.; Neely, D.

2007-09-01

158

Aerosols Over Yellow Sea Sediments  

NASA Technical Reports Server (NTRS)

This SeaWiFS image shows complex phytoplankton distribution patterns in the Bohai and Yellow seas. A wide band of brownish water along the coast north and south of the mouth of the Yangtze River indicates a heavy load of suspended sediment. The air over eastern central China and the Yellow Sea is thick with aerosols. Farther north over the Manchurian Plain and Greater Khingan Range, the air is much clearer.

2002-01-01

159

A unique Yellow River-derived distal subaqueous delta in the Yellow Sea  

E-print Network

A unique Yellow River-derived distal subaqueous delta in the Yellow Sea Z.S. Yang a , J.P. Liu b deposited around the eastern tip of the Shandong Peninsula in the Yellow Sea. This clinoform deposit re-suspended and transported out of the Bohai Sea into the Yellow Sea. Overall, the Yellow River

Liu, Paul

160

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

SciTech Connect

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

Schellhammer, Frank, E-mail: frank.schellhammer@med.uni-duesseldorf.d [University Hospital Duesseldorf, Institute of Diagnostic Radiology (Germany); Esch, Jan Schulte am [University Hospital Duesseldorf, Department of General, Visceral and Pediatric Surgery (Germany); Hammerschlag, Sascha [University Hospital Duesseldorf, Institute of Diagnostic Radiology (Germany); Knoefel, Wolfram Trudo [University Hospital Duesseldorf, Department of General, Visceral and Pediatric Surgery (Germany); Fuerst, Guenter [University Hospital Duesseldorf, Institute of Diagnostic Radiology (Germany)

2008-07-15

161

TAIL VEIN INJECTION (SOP-7) INTRODUCTION  

E-print Network

TAIL VEIN INJECTION (SOP-7) INTRODUCTION Several techniques can be employed which allow within the vein. If the injection is placed subcutaneously, the tail may also blanch but the resistance, the tail can be warmed under a heat lamp. Warming the tail causes the veins to dilate. 3. Locate the right

Kleinfeld, David

162

Hemodilution therapy in central retinal vein occlusion  

Microsoft Academic Search

Systemic hemorheologic abnormalities may play a part in the pathogenesis of central retinal vein occlusions. A statistically significant elevation of plasma viscosity was found in patients with acute central retinal vein occlusion compared with control patients. Local retinal blood flow parameters including arteriovenous passage time and mean arterial dye bolus velocity were significantly altered in the central retinal vein occlusion

Sebastian Wolf; Oliver Arend; Bernd Bertram; Andreas Remky; Karin Schulte; Kenneth J. Wald; Martin Reim

1994-01-01

163

Posterolateral cervical vein as a recipient vein in reconstructive microvascular surgery of the head and neck.  

PubMed

Free flaps are becoming the preferred method of choice for head and neck reconstruction. However, many patients who have undergone radiotherapy and radical neck dissection or who require treatment for recurrent tumor, often present difficulty in choosing recipient vessels. The authors have noted a potential recipient vein coursing vertically along the anterior ridge of the trapezius muscle. They used this vein as the recipient vein in two patients; the two free flaps were transferred successfully without complications. This vein, which they provisionally named the posterolateral cervical vein (PLCV), is considered an important option as a recipient vein in head and neck reconstruction when more commonly used recipient cervical veins are unavailable. PMID:17230316

Yagi, Shunjiro; Nakayama, Bin; Kamei, Yuzuru; Takahashi, Masakathu; Torii, Shuhei

2007-01-01

164

The superficial femoral vein: a valuable conduit for a short renal vein in kidney transplantation.  

PubMed

A variety of techniques have been developed to improve the problem with a short renal vein in kidney transplantation. Those techniques range from thorough mobilization of the recipient common and external iliac veins (iliac vein transposition) to donor vein elongation with a saphenous or gonadal vein or a polytetrafluoroethylene graft. Right renal vein extension using the inferior vena cava represents an excellent option for cadaveric kidney transplantation; however, for kidneys from living donors, that is not a suitable alternative. We present two cases where the superficial femoral vein was used as a conduit with good results; there was no additional morbidity for the patient. Although uncommon, renal vein extensions are sometimes needed in kidney transplantation. The superficial femoral vein comes close to representing the ideal conduit for a short renal vein when compared with a synthetic or an autologous graft due to its diameter and harvesting technique. PMID:19545768

Alcocer, F; Zazueta, E; Montes de Oca, J

2009-06-01

165

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

PubMed Central

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

2014-01-01

166

Attosecond Streaking in the Low-Energy Region  

NASA Astrophysics Data System (ADS)

The low-energy photonelectron (PEs) ionized by a single attosecond pulse can be controlled by a moderately intense infrared field (IR). The electric field of the IR pulse can drive part of the PEs back to the parent ion and induce multiple rescattering of the electrons. Interesting interference patterns are observed in the photoelectron momentum distributions, which are formed by the rescattered electrons and the directly ionized PEs. By analyzing the interference patterns with a simple semiclassical model, which considers the particular PE trajectories incorporating the rescattering with the core, we demonstrate that the low-energy attosecond streaking offers a promising method of holographic imaging of atomic and molecular potential. In addition, we show that neither strong field approximation (SFA) or Coulomb-Volkov approximation (CVA) is able to reproduce these interesting structures at the low energy region.

Geng, Ji-Wei; Peng, Liang-You; Xu, Ming-Hui; Gong, Qihuang

2014-04-01

167

High-speed TV cameras for streak tube readout  

SciTech Connect

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

Yates, G.J.; Gallegos, R.A.; Holmes, V.H. (Los Alamos National Lab., NM (United States)); Turko, B.T. (Lawrence Berkeley Lab., CA (United States))

1991-01-01

168

Laser streaking of free electrons at 25 keV  

NASA Astrophysics Data System (ADS)

Recording electronic motion in atomic systems requires attosecond and picometre resolutions. Current attosecond technology provides photon pulses up to an energy range of 100 eV, with wavelengths far too long to access structures on the atomic scale. In contrast, ultrashort free-electron pulses with sub-Ångstrom de Broglie wavelengths offer the potential to resolve sub-atomic structures. Here, we demonstrate an optical-field-driven streak camera for their temporal characterization. Our concept is to have an electron beam and a laser beam intersect at an ultrathin metal mirror, and potentially offers attosecond resolution. The technique will be instrumental in advancing ultrafast electron diffraction towards ever higher temporal resolution in the pursuit of the long-term goal of sub-atomic four-dimensional imaging. As a first application, we study the influence of electron-electron interactions on the characteristics of few-electron pulses.

Kirchner, F. O.; Gliserin, A.; Krausz, F.; Baum, P.

2014-01-01

169

Replicative intermediates of maize streak virus found during leaf development.  

PubMed

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. PMID:20032206

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

2010-04-01

170

Streaking and Wigner time delays in photoemission from atoms and surfaces  

SciTech Connect

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.

Zhang, C.-H.; Thumm, U. [Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)

2011-09-15

171

Detection Algorithm of Small and Fast orbital objects using Faint Streaks; application to geosynchronous orbit objects  

NASA Astrophysics Data System (ADS)

This paper proposes an algorithm to detect small or apparently fast orbital objects from optical images making use of their faint streaks. In the conventional algorithm, a high signal-to-background-noise-ratio (e.g., 3 or more) is required to detect objects. In our algorithm, we sum signals along the streak direction to improve sensitivity. By applying this algorithm to multi-images, we can detect lower signal-to-noise ratio objects. The algorithm consists of following steps; 1) take local sums of signal intensity on each pixel along preliminarily predicted streak direction, 2) find middle point candidates of streaks on each image, 3) search candidates of a sequence of points aligning in a straight line, and 4) select the candidate with the best linearity and reliability. In this paper, we focus on objects around geosynchronous orbit where most of streaks are oriented to South-North direction. We note that it is not reasonable to apply this algorithm to low Earth orbit objects having no specific streak direction because of limited computational resources. It requires orbit information from other facilities (e.g., space-based sensors). We confirmed that we can detect a streak appeared on images with approximately 1 signal-to-background-noise-ratio with applying the algorithm.

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

172

Smog Yellows Taj Mahal  

NASA Technical Reports Server (NTRS)

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.

2007-01-01

173

Familial central retinal vein occlusion  

Microsoft Academic Search

AimTo report four cases of central retinal vein occlusion (CRVO) in a French family.Patients and methodsOphthalmological examination and medical work-up of seven members of the family.ResultsThere were four cases of CRVO in two consecutive generations. Three of them had CRVO in both eyes. Arterial hypertension was present in two, associated to glaucoma in one. Medical work-up did not reveal additional

J-F Girmens; S Scheer; E Héron; J-A Sahel; E Tournier-Lasserve; M Paques

2008-01-01

174

Central vein stenosis: a nephrologist's perspective.  

PubMed

Central vein stenosis is commonly associated with placement of central venous catheters and devices. Central vein stenosis can jeopardize the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity. Occurrence of central vein stenosis in association with indwelling intravascular devices including short-term, small-diameter catheters such as peripherally inserted central catheters, long-term hemodialysis catheters, as well as pacemaker wires, has been recognized for over two decades. Placement of multiple catheters, longer duration, location in subclavian vein, and placement on the left-hand side of neck seem to predispose to the development of central vein stenosis. Endothelial injury with subsequent changes in the vessel wall results in development of microthrombi, smooth muscle proliferation, and central vein stenosis. Central vein stenosis is often asymptomatic in nondialysis patients, but can result in edema of ipsilateral extremity and breast when challenged by increased flow from an arteriovenous fistula or arteriovenous graft. Bilateral central vein stenosis or superior vena cava stenosis can produce a clinical picture of superior vena cava syndrome, associated with engorgement of face and neck. Endovascular interventions are the mainstay of management of central vein stenosis. Percutaneous angioplasty and stent placement for elastic and recurring lesions can restore the functionality of the vascular access, at least temporarily. Frequent or multiple interventions are usually required. In recalcitrant cases, surgical bypass of the obstruction is an option. In resistant cases with severe symptoms, occlusion of the functioning vascular access will usually provide relief of symptoms. Further study of mechanisms of development of central vein stenosis and search for a targeted therapy is likely to lead to better ways of managing central vein stenosis. Prevention of central vein stenosis is the key to avoid access failure and other complications from central vein stenosis and relies upon avoidance of central vein stenosis placement and timely placement of arteriovenous fistula in prospective dialysis patient. PMID:17244123

Agarwal, Anil K; Patel, Bhairavi M; Haddad, Nabil J

2007-01-01

175

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

SciTech Connect

'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.

Brumby, Steven P.; Vaniman, D. T. (David T.); Bish, D. L. (David L.)

2003-01-01

176

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

PubMed

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

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

2012-10-01

177

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

PubMed

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

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

2012-01-15

178

Ultra fast x-ray streak camera for ten inch manipulator based platformsa)  

NASA Astrophysics Data System (ADS)

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

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

2012-10-01

179

Blue Nevus with a Dermoscopic Appearance of Peripheral Streaks with Branches  

PubMed Central

Blue nevi are dermal dendritic melanocytic proliferations presenting as papules, nodules or plaques of blue, blue-gray or blue-brown color. Dermoscopic appearance commonly shows global patterns as homogeneous mono/dichromatic pigmentation and multichromatic pigmentation. Here, we report the case of a blue nevus with the dermoscopic feature of peripheral streaks with branches. With histopathologic deep sections, we confirmed that dermal dendritic melanocytes were distributed in the direction of the streaks. We emphasize that streaks are a rare but important sign of blue nevi. PMID:24707253

Sakamoto, Sachiko; Oiso, Naoki; Narita, Tomohiko; Kawada, Akira

2014-01-01

180

Ultra Fast X-ray Streak Camera for TIM Based Platforms  

SciTech Connect

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.

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

2012-05-02

181

Bigeminal pulmonary vein ectopy suppressed by pulmonary vein isolation.  

PubMed

A 58-year-old man with atrial fibrillation underwent pulmonary vein (PV) isolation (PVI). Bigeminal atrial premature beats persisted from the beginning of the PVI. The cardiac recordings from a basket catheter (BC) revealed the PV ectopic origin in the distal right superior PV. Successful PVI with the guidance of BC was confirmed by the appearance of concealed ectopy. Surprisingly, the PV ectopy completely disappeared immediately after the successful PVI. The findings suggest that the generation of PV trigger is sometimes dependent on left atrial input and that the underlying mechanism of the PV trigger may have been triggered activity or reentry. PMID:18360071

Yamada, Takumi; Murakami, Yoshimasa; Toyama, Junji; Murohara, Toyoaki

2008-01-01

182

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

PubMed Central

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

2012-01-01

183

A Family By Yellow River  

E-print Network

A Family by Yellow River (Outline) Written by CCTV Re-written in English by Kenong Guan This filmed record of a small village community, namely Lijiashan (Li’s Mountains) of Qikou, Shanxi Province, might serve as an illustration for a profoundly...

China Central Television (CCTV)

2005-04-06

184

Anaphylaxis from yellow fever vaccine  

Microsoft Academic Search

Background: There are very few reports of anaphylactic reactions to yellow fever (YF) vaccine in the literature, and these date from the 1940s. Objective: We sought to estimate the rate of YF vaccine–related anaphylaxis. Methods: All reports of adverse reactions to YF vaccine submitted to the Vaccine Adverse Event Reporting System between 1990 and 1997 were reviewed for those meeting

John M. Kelso; Gina T. Mootrey; Theodore F. Tsai

1999-01-01

185

Holocene development of the Yellow River's subaqueous delta, North Yellow Sea  

E-print Network

Holocene development of the Yellow River's subaqueous delta, North Yellow Sea J. Paul Liua,*, John Yellow Sea reveal a 20­40-m-thick subaqueous clinoform delta that wraps around the eastern end of the Shandong Peninsula, extending into the South Yellow Sea. This complex sigmoidal-oblique clinoform

Liu, Paul

186

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

PubMed Central

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

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

2014-01-01

187

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

NASA Astrophysics Data System (ADS)

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

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

2014-07-01

188

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

PubMed

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

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

2014-01-01

189

fisheriesresearch Yellow perch (Perca flavescens) is  

E-print Network

fisheriesresearch feature Yellow perch (Perca flavescens) is an important ecological and economic.g., Evans 1986). Yellow perch are caught from piers, small boats, and party boats; thus, they are available to nearly all segments of the angling public. Historically, yellow perch supported a commercial fishery

Miller, Tom

190

Yellow Sea Thermohaline and Acoustic Variability  

E-print Network

Yellow Sea Thermohaline and Acoustic Variability Peter C Chu, Carlos J. Cintron Naval Postgraduate School, USA Steve Haeger Naval Oceanographic Office, USA #12;Yellow Sea Bottom Sediment Chart · Four Bottom Sediment types 1. MudMud 2. Sand2. Sand 3.3. GravelGravel 4.4. RockRock #12;Yellow Sea Bottom

Chu, Peter C.

191

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

PubMed Central

There exist many variations in the manner of formation, dimensions and place of termination of the central adrenal veins. In addition, some superficial adrenal veins may be substantial in size and may themselves drain directly into the renal veins and/or into other vessels which communicate with azygos and lumbar veins. This provides a route for venous adrenal blood to the heart via the azygos system and the superior vena cava rather than via the inferior vena cava. Variations in the formation and disposition of the renal veins are also described and the patterns of communication between somatic veins (including veins of the azygos and lumbar systems) and the left renal vein are illustrated and discussed in relation to the findings of others. Images Fig. 7 Fig. 8 Fig. 6 PMID:3693053

Monkhouse, W S; Khalique, A

1986-01-01

192

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

NASA Technical Reports Server (NTRS)

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.

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

1999-01-01

193

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

NASA Technical Reports Server (NTRS)

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.

Blumberg, Dan G.; Greeley, Ronald

1995-01-01

194

Treatment of central retinal vein occlusion by injection of tissue plasminogen activator into a retinal vein  

Microsoft Academic Search

Purpose: To report the injection of tissue plasminogen activator into a retinal vein to treat central retinal vein occlusion.Methods: An 81-year-old woman with visual loss of the right eye secondary to central retinal vein occlusion developed central retinal vein occlusion and visual loss in her left eye. Treatment of her left eye with topical ocular hypotensive medications, pentoxifylline, and laser

Jeffrey N. Weiss

1998-01-01

195

Inheritance of yellow-flowered characteristic and yellow pigments in diploid cyclamen ( Cyclamen persicum Mill.) cultivars  

Microsoft Academic Search

The mode of inheritance of the yellow-flowered phenotype of yellow-flowered cyclamen was investigated. All F1 progenies obtained by reciprocal crosses between yellow- and white-flowered cultivars were white-flowered and did not contain chalcone, the main pigment of yellow-flowered cyclamen. The segregation ratio of flower colors in most of F2 and BC1 progenies fitted the expected Mendelian ratio, showing that the yellow-flowered

Takejiro Takamura; Tsuyoshi Tomihama; Ikuo Miyajima

1995-01-01

196

Pedestal Craters and Wind Streaks, South Medusae Fossae  

NASA Technical Reports Server (NTRS)

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.

1999-01-01

197

Serotyping and strain identification of maize streak virus isolates.  

PubMed

Four strains of maize streak virus, namely the Panicum maximum, Digitaria setigera and sugarcane strains, have been identified from 19 isolates by ELISA using polyclonal antisera cross-absorbed with particles of the maize strain. The results suggest there is an epitope of the maize strain which is not dependent on the capsid being intact and which is common to all the members of the group; other strain-specific epitopes are probably conformation-dependent. A specific epitope (probably internal) occurs on the coat protein of a maize strain isolate, D(R)D, grown in D. velutina, that is also present on the coat protein of the D. setigera (previously reported as D. sanguinalis) strain. Specific internal epitopes also occur in the coat proteins of sugarcane and P. maximum strains. The use of indirect ELISA was necessary for accurate serotyping. The serological reactivities of particles of all the members of each type were identical irrespective of the host from which they were extracted. Sap extracts proved to be more reliable sources of antigen than virus preparations, which could vary in their serological reactivity. Nevertheless, serological differentiation index values determined in tests using either type of antigen proved reliable and consistent. PMID:1697327

Pinner, M S; Markham, P G

1990-08-01

198

Serotonin (5HT) in Veins: Not All in Vain  

Microsoft Academic Search

The circulatory system consists of veins and arteries. Com- pared with arteries, veins have been neglected in cardiovascu- lar research. Although veins are significantly less muscular than similarly sized arteries, the contribution of veins to cardiovas- cular homeostasis cannot be left un-noted because veins ac- commodate 70% of the circulating blood. Circulating blood platelets contain the majority of systemic 5-HT

A. Elizabeth Linder; Wei Ni; Jessica L. Diaz; Theodora Szasz; Robert Burnett; Stephanie W. Watts

2007-01-01

199

Facial vein draining into external jugular vein in humans: its variations, phylogenetic retention and clinical relevance  

Microsoft Academic Search

The superficial veins, especially the external jugular vein (EJV), are increasingly being utilized for cannulation to conduct diagnostic procedures or intravenous therapies. Ultrasound-guided venipuncture is a viable possibility in cases of variations in the patterns of superficial veins, and their knowledge is also important for surgeons doing reconstructive surgery. This study was done on 89 dissected adult cadavers (178 sides)

V. Gupta; A. Tuli; R. Choudhry; S. Agarwal; A. Mangal

2003-01-01

200

21 CFR 880.6980 - Vein stabilizer.  

Code of Federal Regulations, 2010 CFR

...prongs. The device is placed on the skin so that the prongs are on either side of a vein and hold it stable while a hypodermic needle is inserted into the vein. (b) Classification. Class I (general controls). The device is exempt from the...

2010-04-01

201

Duplex ultrasonography in portal vein thrombosis  

Microsoft Academic Search

Duplex ultrasonography (US) was performed in 23 patients with portal vein thrombosis. In 7 children and 16 adults, duplex US demonstrated intraluminal thrombi (4 cases), thrombus and periportal collaterals (2 cases), and cavernomatous transformation of the portal vein (17 cases). Real-time US is a suitable means of demonstrating the anatomy of the portal venous system; pulsed Doppler provided information on

Z. Harkányi; M. Temesi; G. Varga; V. Weszelits

1989-01-01

202

That's the Second-Biggest Hitting Streak I've Ever Seen! Verifying Simulated Historical Extremes in Baseball  

Microsoft Academic Search

There is considerable interest in two consecutive game streak records in baseball, namely, the celebrated 56-game hitting streak of Joe DiMaggio and the less famous 84-games-reaching-base streak of Ted Williams, and how likely these records would be predicted to occur if the history of Major League Baseball were repeated. I strive to answer this question through simulated replication using a

Andrew C. Thomas

2010-01-01

203

Element transport in veins during serpentinization  

NASA Astrophysics Data System (ADS)

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 ?m and > 200 ?m, respectively, from the orthopyroxene. We infer that brucite is not stable in close proximity to orthopyroxene due to elevated SiO2 derived from orthopyroxene breakdown. Orthopyroxene serpentinization results in net transfer of Al2O3 into serpentine, but only in the immediate vicinity of the orthopyroxene. Overall, our study indicates that the extent of orthopyroxene serpentinization controls SiO2 and Al2O3 availability in the fluid and therefore the mineral assemblages present in the veins. The net transfer of SiO2 is manifested by the lack of talc in serpentine veins in orthopyroxene and the lack of brucite in serpentine veins proximal to orthopyroxene grain boundaries. Within veins, local transport of Si, Mg and Fe takes place during reaction of serpentine + brucite with H2O to form magnetite + Mg-rich serpentine + Mg-rich brucite.

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

2013-12-01

204

21 CFR 880.6970 - Liquid crystal vein locator.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Liquid crystal vein locator. 880.6970 Section 880...Miscellaneous Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a device used to...

2010-04-01

205

21 CFR 880.6970 - Liquid crystal vein locator.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Liquid crystal vein locator. 880.6970 Section 880...Miscellaneous Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a device used to...

2012-04-01

206

21 CFR 880.6970 - Liquid crystal vein locator.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Liquid crystal vein locator. 880.6970 Section 880...Miscellaneous Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a device used to...

2013-04-01

207

21 CFR 880.6970 - Liquid crystal vein locator.  

...2014-04-01 2014-04-01 false Liquid crystal vein locator. 880.6970 Section 880...Miscellaneous Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a device used to...

2014-04-01

208

21 CFR 880.6970 - Liquid crystal vein locator.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Liquid crystal vein locator. 880.6970 Section 880...Miscellaneous Devices § 880.6970 Liquid crystal vein locator. (a) Identification. A liquid crystal vein locator is a device used to...

2011-04-01

209

Enhancing the contrast of subcutaneous veins  

NASA Astrophysics Data System (ADS)

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

Zeman, Herbert D.; Lovhoiden, Gunnar

1999-07-01

210

[News in the lower extremity veins morphology].  

PubMed

This comprehensive article notifies on the latest information concerning the morphology of the lower extremity veins, including their anatomical terminology. As a consequence of vehement development of the diagnostic and therapeutic techniques, the more detailed knowledge of anatomy, terminology, venous system variants and venous wall structure is necessary both for the phlebologists, sonographists and for the surgeons and cardiosurgeons. The histological part brings information about the content of collagen and elastin fibers in all layers of the superficial veins wall and about the arrangement of the vasa vasorum in both normal and varicose vena saphena magna. The anatomical-terminological part enlightens the variability of the superficial venous system of the lower extremity and the completion of the terminology of some superficial and deep veins, veins of the pelvis and perforating veins. The simple and clear anatomical terminology is the base for easy and non-problematic communication and discussion between inland and foreign specialists. PMID:19110951

Riedlová, J; Smrzová, T

2008-10-01

211

A high degree of African streak virus diversity within Nigerian maize fields includes a new mastrevirus from Axonopus compressus.  

PubMed

The A-strain of maize streak virus (MSV-A; genus Mastrevirus, family Geminiviridae), the causal agent of maize streak disease, places a major constraint on maize production throughout sub-Saharan Africa. In West-African countries such as Nigeria, where maize is not cultivated year-round, this MSV strain is forced to overwinter in non-maize hosts. In order to both identify uncultivated grasses that might harbour MSV-A during the winter season and further characterise the diversity of related maize-associated streak viruses, we collected maize and grass samples displaying streak symptoms in a number of Nigerian maize fields. From these we isolated and cloned 18 full mastrevirus genomes (seven from maize and 11 from various wild grass species). Although only MSV-A isolates were obtained from maize, both MSV-A and MSV-F isolates were obtained from Digitaria ciliaris. Four non-MSV African streak viruses were also sampled, including sugarcane streak Reunion virus and Urochloa streak virus (USV) from Eleusine coacana, USV from Urochloa sp., maize streak Reunion virus (MSRV) from both Setaria barbata and Rottboellia sp., and a novel highly divergent mastrevirus from Axonopus compressus, which we have tentatively named Axonopus compressus streak virus (ACSV). Besides the discovery of this new mastrevirus species and expanding the known geographical and host ranges of MSRV, we have added D. ciliaris to the list of uncultivated species within which Nigerian MSV-A isolates are possibly able to overwinter. PMID:24796552

Oluwafemi, Sunday; Kraberger, Simona; Shepherd, Dionne N; Martin, Darren P; Varsani, Arvind

2014-10-01

212

An Optical Streaking Method for Measuring Femtosecond Electron Bunches  

SciTech Connect

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

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

2011-12-14

213

[Causes of postoperative recurrent varicose veins of lower extremities].  

PubMed

We analysed venograms of recurrent varicose veins in 180 cases (206 lower limbs). Deep vein valvular insufficiency resulted in varicose veins in 52.9% cases, and post-thrombotic syndrome in 18.9%. The causes of postoperative recurrent varicose veins varied: blindly performed single superficial veins operation, low ligation of the long saphenous trunk, incomplete stripping of varicose veins, missing of the short varicose saphena or incomplete ligation of the perforating veins and failure of deep vein valvular repairs. Venography is of value in making correct diagnosis and choosing appropriate operations. PMID:7553147

Gu, X; Yang, Z; Chen, J

1995-06-01

214

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

PubMed Central

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

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

215

A Reappraisal of Saphenous Vein Grafting  

PubMed Central

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

Yuan, Shi-Min; Jing, Hua

2011-01-01

216

CONTROLLING YELLOW-BILLED MAGPIES (Pica nuttalli)  

Microsoft Academic Search

The yellow-billed magpie is a little smaller than the American or black-billed magpie, but the difference in size is very slight. The birds look exactly alike, except one has a black beak and the other has a yellow bill and a bit of yellow skin back of the eye.There are concentrated populations in the Los Banos area, Gustine area, and

Lynda Rex II

1962-01-01

217

Operational experience with optical streak cameras at the National Ignition Facility  

NASA Astrophysics Data System (ADS)

The National Ignition Facility (NIF) utilizes over 6 optical streak camera systems that collect data from 350 to 1053 nm band during a full system laser shot. The camera systems are configured to collect single or multiple intensity profile signals, spectrally resolved data, spatially resolved interferometry data, and spatially resolved intensity data. The output data format represents the temporal resolution of the recorded event as a two dimensional image. For all these configurations, the time record ranges from 3ns to 100 ns. The precision of the recorded data requires several calibration techniques that provide an overall 2D space-time warp correction that is applied to the raw streak data. The article shall review the typical applications of the optical streak cameras on NIF, the performance of the calibration applied to shot data while in operation and the overall performance and reliability of the camera systems over the several years of operation.

Datte, Philip; Celliers, Peter; Kalantar, Daniel; Moody, John; Bond, Essex; Hibbard, Robin; Krauter, Kerry; Nelson, Jarom; Warrick, Abbie

2013-09-01

218

MAPping Out Arteries and Veins  

NSDL National Science Digital Library

Growing evidence suggests that a genetic program specifies the identity of arteries and veins before the onset of circulation. A signaling cascade involving sonic hedgehog (Shh), vascular endothelial growth factor (VEGF), the VEGF receptor 2 (VEGFR2), homeobox proteins Foxc1 and Foxc2, the Notch receptor, and the downstream transcription factor gridlock is required for expression of arterial markers, whereas only a single transcription factor, COUP-TFII (chicken ovalbumin upstream promoter–transcription factor II), has previously been implicated in maintaining venous fate. Recent work has now implicated two competing pathways downstream of VEGFR2 in arterial versus venous specification: Activation of the phospholipase C–γ (PLC-γ)–mitogen-activated protein kinase (MAPK) pathway acts in arterial specification, whereas the phosphoinositide 3-kinase (PI3K)–Akt pathway acts to allow a venous fate by inhibition of the PLC-γ–MAPK pathway. Here, we review this work and discuss how activation of the MAPK signaling cascade could stimulate an arterial fate.

Ryan E. Lamont (Canada;University of Calgary, Calgary AB REV); Sarah Childs (Canada;University of Calgary, Calgary AB REV)

2006-10-03

219

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

SciTech Connect

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

Zhang, C.-H.; Thumm, U. [Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)

2011-12-15

220

Dielectric response effects in attosecond time-resolved streaked photoelectron spectra of metal surfaces  

E-print Network

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

Zhang, Chang-hua

2011-01-01

221

A Monte Carlo Approach to Joe DiMaggio and Streaks in Baseball  

E-print Network

We examine Joe DiMaggio's 56-game hitting streak and look at its likelihood, using a number of simple models. And it turns out that, contrary to many people's expectations, an extreme streak, while unlikely in any given year, is not unlikely to have occurred about once within the history of baseball. Surprisingly, however, such a record should have occurred far earlier in baseball history: back in the late 1800's or early 1900's. But not in 1941, when it actually happened.

Arbesman, S

2008-01-01

222

Optimizing data recording for the NIF core diagnostic x-ray streak camera  

NASA Astrophysics Data System (ADS)

Quantitative measurements of the sensitivity, dynamic range, and image resolution of a Nova secondary ion mass-based x-ray streak camera have been made. Comparisons were made using film versus a 4k×4k optical charge-coupled device for data readout. These tests were performed with and without an optical image intensifier tube, and with a direct electron-sensitive microchannel plate. We present results from these tests and recommendations for the National Ignition Facility core x-ray streak camera.

Kalantar, D. H.; Bell, P. M.; Perry, T. S.; Sewall, N.; Kimbrough, J.; Weber, F.; Diamond, C.; Piston, K.

2001-01-01

223

A grazing incidence x-ray streak camera for ultrafast, single-shot measurements  

SciTech Connect

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.

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

224

Accurate and efficient characterization of streak camera using etalon and fitting method with constraints.  

PubMed

Streak camera is widely used in continuous time diagnostics in fast physical process. To produce accurate result, it requires delicate calibration and a reliable analysis method. High quality sweep-rate data with uncertainty smaller than 0.5% are obtained over the full record area by a constrained fitting method of peak position measurement, with a short pulse laser and an etalon as the fiducial source. The temporal response is linearized by this full-screen sweep-rate data, which eliminates errors in measurement due to nonlinearity and space-distortion inherent in streak camera. PMID:22128970

Yang, Dong; Wang, Zhebin; Jiang, Xiaohua; Liu, Yonggang; Peng, Xiaoshi; Zhu, Tuo; Zhang, Huan; Li, Zhichao; Li, Sanwei; Ding, Yongkun

2011-11-01

225

Inhibition of maize streak virus (MSV) replication by transient and transgenic expression of MSV replication-associated protein mutants  

Microsoft Academic Search

Maize streak disease is a severe agricultural problem in Africa and the development of maize genotypes resistant to the causal agent, Maize streak virus (MSV), is a priority. A transgenic approach to engineering MSV-resistant maize was developed and tested in this study. A pathogen- derived resistance strategy was adopted by using targeted deletions and nucleotide-substitution mutants of the multifunctional MSV

Dionne N. Shepherd; Tichaona Mangwende; Darren P. Martin; Marion Bezuidenhout; Jennifer A. Thomson; Edward P. Rybicki

2007-01-01

226

Epithelioid hemangioendothelioma encasing the left brachiocephalic vein  

PubMed Central

Epithelioid hemangioendotheliomas are rare vascular tumors, often arising from medium to large veins in the extremities. Symptoms of these tumors vary depending upon location. Rarely, tumors may arise in chest and involve large vessels in the mediastinum. We present a case of a 17-year-old male presenting with compressive symptoms of the left upper extremity who was found to have a large epithelioid hemangioendothelioma encasing the left brachiocephalic vein. PMID:24898409

Long, Kristin; Skinner, Sean; Martin, Jeremiah

2014-01-01

227

Gross anatomy of primary varicose veins observed in endoscopic surgery.  

PubMed

The gross anatomy of varicose veins is one of the most important factors in the study of varicosity. Because of wide variations in the extent of involvement and degree of severity of varicose veins, it is difficult to obtain live and intact specimens of varicose veins. With good illumination and magnified monitor viewing, the varicositic main channel, its tributaries, and the incompetent perforating veins can be dissected and visualized clearly during endoscopic surgery. Thus, the whole range of varicosities can be observed directly in situ. Characteristic features of the varicosities of 350 limbs have been recorded by video and photographs for study and classification. These features include: 1) poor contractility of varicose veins; 2) dilated and tortuous changes of varicose veins; 3) saccular or lateral bulging deformities of vein walls, or both; 4) uniformly dilated and tortuous deformities of a long vein; 5) varicositic changes of the accessory vein; 6) anatomic abnormalities of varicose veins, such as supernumerary tributaries, varicositic clusters, and a crowded relationship among the long saphenous vein, perforating vein and tributaries; 7) various conditions of the perforating veins; and 8) the close relationship among the long saphenous vein, perforating veins, and the saphenous nerve. These data provide valuable information for the study and management of primary varicose veins. PMID:12461435

Lin, Sin-Daw; Chang, Kao-Ping; Yang, Yu-Li; Lee, Su-Shin; Lin, Tsai-Ming; Tsai, Chih-Cheng; Lai, Chung-Sheng

2002-12-01

228

Veins improve fracture toughness of insect wings.  

PubMed

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

Dirks, Jan-Henning; Taylor, David

2012-01-01

229

Scattering Removal for Finger-Vein Image Restoration  

PubMed Central

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

Yang, Jinfeng; Zhang, Ben; Shi, Yihua

2012-01-01

230

21 CFR 172.490 - Yellow prussiate of soda.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Yellow prussiate of soda. 172.490 Section 172.490 Food and...Agents § 172.490 Yellow prussiate of soda. (a) The food additive yellow prussiate of soda (sodium ferrocyanide decahydrate; Na4...

2010-04-01

231

History of Epidemiological Aspects of Yellow Fever  

PubMed Central

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

Downs, Wilbur G.

1982-01-01

232

Love is Yellow in Vietnamese Popular Music  

E-print Network

Yellow music is a profane practice that makes children cry;children in tears; they are unable study their lessons due to the musical affect of yellow musicmusic was critiqued in the media (ibid). In the cartoon of the crying the children,

Nguyen, Minh Xuan

2012-01-01

233

Outcome of patients with pre-existing portal vein thrombosis undergoing arterialization of the portal vein during liver transplantation  

Microsoft Academic Search

Arterialization of the portal vein is being propagated as a technical possibility in liver transplant recipients with pre-existing portal vein thrombosis. In our own small series, portal vein arterialization (PVA) was carried out in four patients undergoing orthotopic liver transplantation. In three of these cases, the portal vein was anastomosed to the aorta via an interposed iliac artery, and in

Rudolf Ott; Cathrin Böhner; Susanna Müller; Thomas Aigner; Michaela Bussenius-Kammerer; Suleyman Yedibela; Hermann Kissler; Werner Hohenberger; Thomas Reck; Volker Müller

2003-01-01

234

Minor vein structure and sugar transport in Arabidopsis thaliana  

Microsoft Academic Search

.   Leaf and minor vein structure were studied in Arabidopsis thaliana (L.) Heynh. to gain insight into the mechanism(s) of phloem loading. Vein density (length of veins per unit leaf area) is\\u000a extremely low. Almost all veins are intimately associated with the mesophyll and are probably involved in loading. In transverse\\u000a sections of veins there are, on average, two companion

Edith Haritatos; Richard Medville; Robert Turgeon

2000-01-01

235

Cephalic Vein Transposition versus Vein Grafts for Venous Outflow in Free-flap Breast Reconstruction  

PubMed Central

Introduction: When recipient veins for free-flap breast reconstruction are unavailable or inadequate, vein grafts or cephalic vein transposition (CVT) an option to provide alternate venous outflow. There are no comparative data to elucidate the indications and outcomes for each. We hypothesize that the CVT is as reliable as vein grafts when indicated. Methods: All consecutive cases where a CVT or venous vein grafts were used for free-flap breast reconstruction between 2000 and 2012 were reviewed. Patient demographics, operative notes, indications, and flap survival were compared between the 2 groups. Results: Ten patients underwent a CVT and 38 patients received a vein graft for insufficient venous outflow. There were no differences in average age, body mass index, or comorbid conditions between the groups. Similarly, there was no difference in previous radiotherapy, timing of reconstruction, or side of reconstruction. A CVT was used for salvage following venous thrombosis in 7 patients (70.0%) and for primary venous outflow in the remaining patients due to inability to use the internal mammary vein. Vein grafts were performed primarily in 31 patients, 22 for augmenting venous drainage (supercharge), 9 for the dominant venous outflow, and 7 for salvage of a thrombosis. One patient in each group suffered a complete loss of the free flap (cephalic: 10.0% vs vein graft: 14.3%, P = 0.36). Conclusions: The CVT is a reliable alternate venous outflow that can be used as a primary recipient vein or as a salvage option following venous thrombosis. Surgeons should consider a CVT when primary recipient veins are compromised or unavailable. PMID:25289334

Chang, Edward I.; Fearmonti, Regina M.; Chang, David W.

2014-01-01

236

The pink topaz-bearing calcite, quartz, white mica veins from Ghundao Hill (North West Frontier Province, Pakistan): K\\/Ar age, stable isotope and REE data  

Microsoft Academic Search

Summary  In the area of the Ghundao Hill (Northern Frontier Province, Pakistan) an orange-yellow to cherry-red topaz is found in calcite,\\u000a quartz, white mica veins crosscutting the schistosity of probably Silurian to Devonian gray limestones. Topaz with such a\\u000a range of colours is traded as Imperial Topaz. Low fluorine contents of about 15?wt.%, oxygen isotope thermometry, K\\/Ar age\\u000a determination on white

G. Morteani; A. Voropaev

2007-01-01

237

Host range and some characterization of Tobacco streak virus isolated from lettuce in Iran  

Microsoft Academic Search

Lettuce (Lactuca sativa) is one of the most common vegetable planted in the world, so the identification of its viral disease is important because this kind of pathogen causes the loss of quantitative and qualitative characteristic of lettuce. Tobacco streak virus (TSV) is an ilarvirus with quasi-isometric particles, 27 - 35 nm in diameter. It has a wide host range

F. S. Abtahi; M. Koohi Habibi

2008-01-01

238

Microrobotic Streak Seeding For Protein Crystal Growth CUCS-041-04  

E-print Network

Microrobotic Streak Seeding For Protein Crystal Growth CUCS-041-04 Atanas Georgiev1 , Peter K the task known as crystal mounting that consists of picking an individual protein crystal from its growth Abstract We present a microrobotic system for protein crystal micromanipulation tasks. The focus

239

Asymmetric Vshaped streaks recorded on board DEMETER satellite above powerful thunderstorms  

E-print Network

Asymmetric Vshaped streaks recorded on board DEMETER satellite above powerful thunderstorms F. El are associated with intense and numerous 0+ whistlers generated in the VLF range by active thunderstorms network. A relationship between the local inclination of the magnetic field above active thunderstorms

240

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

SciTech Connect

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.

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

1991-01-01

241

Photoemissive materials for 0. 35. mu. m laser fiducials in x-ray streak cameras  

SciTech Connect

Using a soft x-ray streak camera, materials are tested for suitability as transmission photocathodes when irradiated by 0.35..mu..m laser pulses. Preliminary measurements of sensitivity, dynamic range and temporal resolution are reported. A practical fiber optic fiducial under development for laser fusion x-ray diagnostics on the LLNL Nova laser system is described.

Hale, C.P.; Medecki, H.; Lee, P.H.Y.

1984-01-01

242

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

SciTech Connect

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.

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

1981-08-28

243

Improvements in avalanche-transistor sweep circuitry for electrooptic streak cameras  

Microsoft Academic Search

The performance of the avalanche transistor deflector driver (sweep) circuitry used in the high speed, electrooptic streak camera was improved. In the previous design for the sweep circuit, trigger to output delay time drifted on some cameras. This delay drift is a function of a somewhat randomly unstable breakdown voltage of some avalanche transistors. Both temperature and differences in manufacturing

S. W. Thomas; R. L. Griffith; W. R. McDonald

1984-01-01

244

Picosecond streak camera display of an intermodal coupling matrix at a multimode fiber splice  

NASA Technical Reports Server (NTRS)

A technique is developed that permits direct visualization of the coupling matrix for all guided modes of a moderately multimode fiber optic at a splice or mode coupler. The matrix is formed by an array of spots at the output of a picosecond streak camera. The technique also permits unambiguous determination of the phase velocity and group velocity of the modes.

Louradour, F.; Shaklan, Stuart

1991-01-01

245

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

PubMed

The x-ray streak camera and x-ray framing camera for the National Ignition Facility were redesigned to improve electromagnetic pulse hardening, protect high voltage circuits from pressure transients, and maximize the use of common parts and operational software. Both instruments use the same PC104 based controller, interface, power supply, charge coupled device camera, protective hermetically sealed housing, and mechanical interfaces. Communication is over fiber optics with identical facility hardware for both instruments. Each has three triggers that can be either fiber optic or coax. High voltage protection consists of a vacuum sensor to enable the high voltage and pulsed microchannel plate phosphor voltage. In the streak camera, the high voltage is removed after the sweep. Both rely on the hardened aluminum box and a custom power supply to reduce electromagnetic pulse/electromagnetic interference (EMP/EMI) getting into the electronics. In addition, the streak camera has an EMP/EMI shield enclosing the front of the streak tube. PMID:21034058

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

2010-10-01

246

Deblurring Low-light Images with Light Streaks Sunghyun Cho2  

E-print Network

Deblurring Low-light Images with Light Streaks Zhe Hu1 Sunghyun Cho2 Jue Wang2 Ming-Hsuan Yang1 1 University of California, Merced 2 Adobe Research Abstract Images taken in low-light conditions with handheld been made recently on image deblurring, state-of-the-art approaches often fail on low-light images

Yang, Ming-Hsuan

247

Holographic particle-streak velocimetry Lisa Dixon, Fook Chiong Cheong and David G. Grier  

E-print Network

Holographic particle-streak velocimetry Lisa Dixon, Fook Chiong Cheong and David G. Grier. Willert, S. T. Wereley, and J. Kompenhans, Particle Image Velocimetry: A Practical Guide (Springer, Berlin and motions," Appl. Opt. 45(16), 3893�3901 (2006). 1. Introduction Particle image velocimetry (PIV) is widely

Grier, David

248

Projected and slice emittance measurements using multi-quadrupole scan and streak readout at PITZ  

E-print Network

Projected and slice emittance measurements using multi-quadrupole scan and streak readout at PITZ R electron beam. One of the main characteristics of the beam is its normalized emittance. Development of injectors is targeted towards producing beams with low normalized emittance, thus high resolution emittance

249

Deep vein thrombosis: a clinical review  

PubMed Central

Background: Deep vein thrombosis (DVT) is the formation of blood clots (thrombi) in the deep veins. It commonly affects the deep leg veins (such as the calf veins, femoral vein, or popliteal vein) or the deep veins of the pelvis. It is a potentially dangerous condition that can lead to preventable morbidity and mortality. Aim: To present an update on the causes and management of DVT. Methods: A review of publications obtained from Medline search, medical libraries, and Google. Results: DVT affects 0.1% of persons per year. It is predominantly a disease of the elderly and has a slight male preponderance. The approach to making a diagnosis currently involves an algorithm combining pretest probability, D-dimer testing, and compression ultrasonography. This will guide further investigations if necessary. Prophylaxis is both mechanical and pharmacological. The goals of treatment are to prevent extension of thrombi, pulmonary embolism, recurrence of thrombi, and the development of complications such as pulmonary hypertension and post-thrombotic syndrome. Conclusion: DVT is a potentially dangerous condition with a myriad of risk factors. Prophylaxis is very important and can be mechanical and pharmacological. The mainstay of treatment is anticoagulant therapy. Low-molecular-weight heparin, unfractionated heparin, and vitamin K antagonists have been the treatment of choice. Currently anticoagulants specifically targeting components of the common pathway have been recommended for prophylaxis. These include fondaparinux, a selective indirect factor Xa inhibitor and the new oral selective direct thrombin inhibitors (dabigatran) and selective factor Xa inhibitors (rivaroxaban and apixaban). Others are currently undergoing trials. Thrombolytics and vena caval filters are very rarely indicated in special circumstances. PMID:22287864

Kesieme, Emeka; Kesieme, Chinenye; Jebbin, Nze; Irekpita, Eshiobo; Dongo, Andrew

2011-01-01

250

Experimental therapies for yellow fever  

PubMed Central

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

Julander, Justin G.

2013-01-01

251

Formation and evolution of a hairpin vortex induced by subharmonic sinuous low-speed streaks  

NASA Astrophysics Data System (ADS)

In this paper, a process of the formation and evolution of hairpin vortices, which originated from the interaction between the spanwise-aligned low-speed streaks with a subharmonic sinuous (SS) oscillation mode, is studied using a direct numerical simulation method in a small periodic local region of an incompressible plane channel flow. The initial artificial perturbations are used to excite the SS-mode oscillation of two spanwise-aligned low-speed streaks in such a flow. A new mechanism of formation and decay of the hairpin vortices is proposed in which the shear layer induced by the spanwise collision and merging between the low-speed streaks is emphasized. Our results show that the streamwise vortices can be induced by the SS-mode streaks and then developed into an X-like pattern at the initial stage due to the mutual induction effect. The X-like vortices further enhance the spanwise oscillation and lift-up of the two streaks that thus lead to the spanwise collision and merging of the low-speed streaks and produce a low-speed region in high-speed fluid. The strong shear layer between the high- and low-speed fluids gives rise to the spanwise vorticity that connects the X-like streamwise vortices and forms the ?-like vortex. Once the low-speed region entirely enters the high-speed fluid, the shear layer shows the ring shape and results in the transition from a ?-like vortex to ?-like one. After that, the viscous diffusion of the low-speed region in the high-speed fluid leads to the decay of the ?-like vortex; the collision and merging of the low-speed streaks simultaneously reoccur upstream and give birth to a secondary ?-like vortex, which exhibits behavior that is nearly similar with that of the primary one. Although the hairpin vortex packet is not observed in the present plane channel flow, the regeneration of the hairpin vortex suggests that this type of vortical structure plays an important role in the wall-bounded flow.

Li, Jian; Dong, Gang; Lu, Ziheng

2014-10-01

252

Varicose Veins, Deep Vein Thrombosis, and Haemorrhoids: Epidemiology and Suggested Aetiology  

PubMed Central

Current concepts on the aetiology of varicose veins, deep vein thrombosis, and haemorrhoids have been examined and, in the light of epidemiological evidence, found wanting. It is suggested that the fundamental cause of these disorders is faecal arrest which is the result of a low-residue diet. PMID:5032782

Burkitt, Denis P.

1972-01-01

253

Correct patterning of the primitive streak requires the anterior visceral endoderm.  

PubMed

Anterior-posterior axis specification in the mouse requires signalling from a specialised extra-embryonic tissue called the anterior visceral endoderm (AVE). AVE precursors are induced at the distal tip of the embryo and move to the prospective anterior. Embryological and genetic analysis has demonstrated that the AVE is required for anterior patterning and for correctly positioning the site of primitive streak formation by inhibiting Nodal activity. We have carried out a genetic ablation of the Hex-expressing cells of the AVE (Hex-AVE) by knocking the Diphtheria toxin subunit A into the Hex locus in an inducible manner. Using this model we have identified that, in addition to its requirement in the anterior of the embryo, the Hex-AVE sub-population has a novel role between 5.5 and 6.5dpc in patterning the primitive streak. Embryos lacking the Hex-AVE display delayed initiation of primitive streak formation and miss-patterning of the anterior primitive streak. We demonstrate that in the absence of the Hex-AVE the restriction of Bmp2 expression to the proximal visceral endoderm is also defective and expression of Wnt3 and Nodal is not correctly restricted to the posterior epiblast. These results, coupled with the observation that reducing Nodal signalling in Hex-AVE ablated embryos increases the frequency of phenotypes observed, suggests that these primitive streak patterning defects are due to defective Nodal signalling. Together, our experiments demonstrate that the AVE is not only required for anterior patterning, but also that specific sub-populations of this tissue are required to pattern the posterior of the embryo. PMID:21445260

Stuckey, Daniel W; Di Gregorio, Aida; Clements, Melanie; Rodriguez, Tristan A

2011-01-01

254

Twelve signals multiplexed with the Lawrence Livermore National Laboratory (LLNL) optical streak camera  

SciTech Connect

At our Nova laser facility, the temporal history of incident and reflected laser energy is recorded on LLNL optical streak cameras. Currently, six cameras are used to record the incident 1.06-{mu}m, incident 0.35{mu}m power of each of the ten Nova beams. Each camera records seven multiplexed signals: typically one signal from each of five beam lines, a fiducial pulse, and time mark generator signal. The optical signals are transported to the camera through optical fibers. The output end of each fiber is placed in the slit plane of the camera. The light exiting the fiber is focused to the streak camera photocathode by the streak camera relay lens. One camera can record a signal from each of the ten Nova beams plus a fiducial and time mark generator signal if the number of multiplexed channels can be increased from seven to twelve. This would allow one camera to record the same data that currently requires two cameras. At a savings of $150 per camera/CCD system, this represents a savings of $450K. Additionally, camera/CCD maintenance and operation complexity would be cut in half and three streak cameras would be freed for use in other experiments. Recent laboratory measurements suggest that the number of multiplexed signals per camera can indeed be increased from seven to twelve without noticeably increasing the crosstalk between signal channels. In this memorandum, we describe recent work in which seven and twelve signals were multiplexed to one streak camera. We describe the effect focusing has on the crosstalk channels and the effect wavelength has on focusing. We conclude the memorandum with suggestions concerning the implementation of a twelve channel system.

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

1990-08-28

255

Animal Model of Acute Deep Vein Thrombosis  

SciTech Connect

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

Roy, Sumit; Laerum, Frode [Institute for Surgical Research, National Hospital, N-0027 Oslo (Norway); Brosstad, Frank [Research Institute for Internal Medicine, National Hospital, N-0027 Oslo (Norway); Kvernebo, Knut [Department of Surgery, Ulleval Hospital, Kirkevien 166, N-0407 Oslo (Norway); Sakariassen, Kjell S. [Nycomed Bioreg A/S, Forskningsparken, Gaustadalleen 21, N-0371 Oslo (Norway)

1998-07-15

256

Optimization of subcutaneous vein contrast enhancement  

NASA Astrophysics Data System (ADS)

A technique for enhancing the contrast of subcutaneous veins has been demonstrated. This techniques uses a near IR light source and one or more IR sensitive CCD TV cameras to produce a contrast enhanced image of the subcutaneous veins. This video image of the veins is projected back onto the patient's skin using a n LCD video projector. The use of an IR transmitting filter in front of the video cameras prevents any positive feedback from the visible light from the video projector from causing instabilities in the projected image. The demonstration contrast enhancing illuminator has been tested on adults and children, both Caucasian and African-American, and it enhances veins quite well in all cases. The most difficult cases are those where significant deposits of subcutaneous fat are present which make the veins invisible under normal room illumination. Recent attempts to see through fat using different IR wavelength bands and both linearly and circularly polarized light were unsuccessful. The key to seeing through fat turns out to be a very diffuse source of RI light. Results on adult and pediatric subjects are shown with this new IR light source.

Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

2000-05-01

257

A new approach for sclera vein recognition  

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

258

A clinicopathological study of human yellow fever*  

PubMed Central

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

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

1972-01-01

259

A clinicopathological study of human yellow fever.  

PubMed

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

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

1972-01-01

260

Atrioesophageal fistula after cryoballoon pulmonary vein isolation.  

PubMed

The risk of atrioesophageal fistula after cryoballoon pulmonary vein isolation is thought to be much lower than after radiofrequency ablation, seeing that no data exist on this complication so far. We report for the first time on the occurrence of an atrioesophageal fistula 4 weeks after cryoballoon ablation at the site of the left inferior pulmonary vein. We suggest that even when using cryothermal ablation technique, an imaging modality to assess the proximity of esophagus and left atrium should be routinely performed to avoid this fatal complication. PMID:22486804

Stöckigt, Florian; Schrickel, Jan W; Andrié, René; Lickfett, Lars

2012-11-01

261

University of Hawaii at Mnoa Yellow Ribbon Program  

E-print Network

University of Hawaiÿi at Mänoa Yellow Ribbon Program Policies and Procedures 2013 ­ 2014 Academic Year The University of Hawaiÿi at Mänoa (UHM) is participating in the Yellow Ribbon Program (YRP) for the 2013 ­ 2014 academic year. The Yellow Ribbon GI Education Enhancement Program (Yellow Ribbon Program

262

Assessing Sites for Yellow Legged Frog  

USGS Multimedia Gallery

Assessing suitable sites in southern California for reintroducing endangered southern mountain yellow-legged frogs, USGS scientists rediscovered a population in the San Jacinto Wilderness, 50 years since this frog was last seen there....

2009-07-23

263

Lost Trust: A Yellow Fever Patient Response  

PubMed Central

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

Runge, John S.

2013-01-01

264

Teachable Fiction Comes to Yellow Sky.  

ERIC Educational Resources Information Center

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

Tietz, Stephen

2001-01-01

265

Turnip Yellow Mosaic Virus Structure  

NASA Technical Reports Server (NTRS)

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.

2000-01-01

266

Redox alters yellow dragonflies into red  

PubMed Central

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

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

2012-01-01

267

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

SciTech Connect

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

Lumpkin, A.; Yang, B.; Gai, W. [Argonne National Lab., IL (United States); Cieslik, W. [Hamamatsu Photonic Systems, Bridgewater, NJ (United States)

1995-07-01

268

78 FR 24199 - Streak Products, Inc. v. UTi, United States, Inc.; Notice of Filing of Complaint and Assignment  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 13--04] Streak Products, Inc. v. UTi, United States, Inc.; Notice of Filing of Complaint...hereinafter ``Complainant,'' against UTi, United States, Inc. (``UTi''), hereinafter ``Respondent.''...

2013-04-24

269

varicose veins smoking obesity swine flu high blood pressure  

E-print Network

varicose veins smoking obesity swine flu high blood pressure parkinson's stress depression muscle smoking obesity swine flu high blood pressure parkinson's stress depression muscle stiffness heart attack arthritis prostate disease bladder infection incontinence cancer varicose veins smoking obesity swine flu

Diggle, Peter J.

270

Why Do Some Pregnant Women Get Varicose Veins?  

MedlinePLUS

... Social Media: Connect With Us Why Do Some Pregnant Women Get Varicose Veins? KidsHealth > Parents > Q&A > Pregnancy and Infants > Why Do Some Pregnant Women Get Varicose Veins? Print A A A Text ...

271

Tectonic fibrous veins: initiation and evolution. Ouachita Orogen, Arkansas  

E-print Network

these fractures initiate where they do and how the vein evolves once started. We studied veins from the Lower Ordovician Mazarn Formation in the Arkansas’ Ouachitas combining textural observations, stable isotopes, fluid inclusions, SEM-based cathodoluminescence...

Cervantes, Pablo

2009-05-15

272

Portal vein embolization before major hepatectomy  

Microsoft Academic Search

Abstract Abstract Abstract Abstract To discuss the rationale, techniques and the unsolved issues regarding preoperative portal vein embolization (PVE) before major hepatectomy. After a systematic search of Pubmed, we reviewed and retrieved literature related to PVE. Preoperative PVE is an approach that is gaining increasing acceptance in the preoperative treatment of selected patients prior to major hepatic resection. Induction of

Hai Liu; Yong Fu

273

Deep vein thrombosis: related to anemophilous pollen?  

PubMed

The etiology of deep vein thrombosis (DVT) is still not elucidated nowadays. Based on the accordance between DVT incidence and the anemophilous pollen concentration in the air, we proposed the hypothesis that allergic reaction induced by anemophilous pollen may cause "idiopathic" DVT, and proinflammatory factors may play an important role in the thrombosis process. PMID:21823027

Zhou, Bin; Li, Yiqing; Shang, Dan; Dang, Yiping; Wang, Weici; Sheng, Shi; Kong, Xianghai; Jin, Bi

2011-08-01

274

Thoracic Outlet Decompression for Subclavian Vein Thrombosis  

Microsoft Academic Search

Hypothesis:Thereisadifferenceinoutcomeswhenpa- tients have neurogenic thoracic outlet syndrome in ad- dition to subclavian vein thrombosis. Methods: Analysis of a prospectively developed data- base, medical record review, and a patient question- naire were used to summarize clinical experience from December 1990 to December 2001 on the basis of the patient's original evaluation. Patients were stratified on the presence (group 1) or absence

Vasu Divi; Mary C. Proctor; David A. Axelrod; Lazar J. Greenfield

2005-01-01

275

Endoscopic vein harvesting: technique, outcomes, concerns & controversies  

PubMed Central

The choice of the graft conduit for coronary artery bypass grafting (CABG) has significant implications both in the short- and long-term. The patency of a coronary conduit is closely associated with an uneventful postoperative course, better long-term patient survival and superior freedom from re-intervention. The internal mammary artery is regarded as the primary conduit for CABG patients, given its association with long-term patency and survival. However, long saphenous vein (LSV) continues to be utilized universally as patients presenting for CABG often have multiple coronary territories requiring revascularization. Traditionally, the LSV has been harvested by creating incisions from the ankle up to the groin termed open vein harvesting (OVH). However, such harvesting methods are associated with incisional pain and leg wound infections. In addition, patients find such large incisions to be cosmetically unappealing. These concerns regarding wound morbidity and patient satisfaction led to the emergence of endoscopic vein harvesting (EVH). Published experience comparing OVH with EVH suggests decreased wound related complications, improved patient satisfaction, shorter hospital stay, and reduced postoperative pain at the harvest site following EVH. Despite these reported advantages concerns regarding risk of injury at the time of harvest with its potential detrimental effect on vein graft patency and clinical outcomes have prevented universal adoption of EVH. This review article provides a detailed insight into the technical aspects, outcomes, concerns, and controversies associated with EVH. PMID:24251019

Sarang, Zubair

2013-01-01

276

Central retinal vein occlusion in young people  

Microsoft Academic Search

In a study performed on 20 subjects with central retinal vein occlusion (CRVO) aged 40 years or less we found the ischemic form in 20%. Disc edema was a common finding at the onset, while macular edema was less frequently seen. Systemic or ocular disorders that could be related with the development of the CRVO were often found; a patient

Giuseppe Giuffré; Gaetano Randazzo-Papa; Carlo Palumbo

1992-01-01

277

Management of Central Retinal Vein Occlusion  

Microsoft Academic Search

The management of central retinal vein occlusion (CRVO) is discussed briefly. Since the prognosis, complications, visual outcome and management of nonischemic and ischemic CRVO are very different, the first essential step in the management of CRVO is to determine which type of CRVO one is dealing with. The various parameters which help to differentiate the two types reliably are described

Sohan Singh Hayreh

2003-01-01

278

Progression of Nonischemic Central Retinal Vein Occlusion  

Microsoft Academic Search

Progression of nonischemic central retinal vein occlusion (CRVO) to ischemic CRVO occurs in up to 5–20 % of patients with nonischemic CRVO. Eyes presenting with nonischemic CRVO and exhibiting an increase in intraretinal hemorrhages together with angiographic findings of aggravation of venule wall staining were assumed to be showing early signs of progression. Eight eyes of 7 patients were followed

A. Pollack; H. Leiba; M. Oliver

1997-01-01

279

Central retinal vein occlusion and thrombophilia  

Microsoft Academic Search

Central retinal vein occlusion is one of the commonest vascular diseases of the eye. The pathogenesis is multifactorial with both local factors and systemic diseases being aetiologically important. Many thrombophilic conditions have recently been identified and studies looking at their potential role in CRVO have been undertaken. The aim of this review is to critically appraise these studies as to

C D Fegan

2002-01-01

280

Preoperative portal vein embolization for hepatocellular carcinoma  

Microsoft Academic Search

As a countermeasure to portal tumor thrombi, which are a serious danger in liver cancer, we did portal vein embolization (PVE) during percutaneous transhepatic portography. Our 21 patients later underwent hepatic resection. After PVE, portal pressure increased and there was slight liver function damage, but this procedure was safer than transarterial embolization (TAE). We examined the pathologic specimens to view

Hiroaki Kinoshita; Katsuji Sakai; Kazuhiro Hirohashi; Sumito Igawa; Osamu Yamasaki; Shoji Kubo

1986-01-01

281

Streaked radiography of an irradiated foam sample on the National Ignition Facility  

SciTech Connect

Streaked x-ray radiography images of annular patterns in an evolving tantalum oxide foam under the influence of a driven, subsonic radiation wave were obtained on the National Ignition Facility. This is the first successful radiography measurement of the evolution of well-defined foam features under a driven, subsonic wave in the diffusive regime. A continuous record of the evolution was recorded on an x-ray streak camera, using a slot-apertured point-projection backlighter with an 8 ns nickel source (7.9 keV). Radiography images were obtained for four different annular patterns, which were corrected using a source-dependent flat-field image. The evolution of the foam features was well-modeled using the 3D KULL radiation hydrodynamics code. This experimental and modeling platform can be modified for scaled high-energy-density laboratory astrophysics experiments.

Cooper, A. B. R.; Schneider, M. B.; MacLaren, S. A.; Young, P. E.; Hsing, W. W.; Seugling, R.; Foord, M. E.; Sain, J. D.; May, M. J.; Marrs, R. E.; Maddox, B. R.; Lu, K.; Dodson, K.; Smalyuk, V. [Lawrence Livermore National Laboratory, 7000 East Ave Livermore, California 94550 (United States); Moore, A. S.; Graham, P.; Foster, J. M. [Atomic Weapons Establishment, Aldermaston, Reading RG7 4PR (United Kingdom); Back, C. A.; Hund, J. F. [General Atomics, San Diego, California 92121 (United States)

2013-03-15

282

Time-resolved spectra of dense plasma focus using spectrometer, streak camera, and CCD combinationa)  

NASA Astrophysics Data System (ADS)

A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially Czerny-Turner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments.

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

2010-10-01

283

Attochirp-corrected photo ionization time delays using coincidence attosecond streaking  

E-print Network

Recent measurements have demonstrated the possibility of probing single-photon ionization time delays of electrons originating from different initial states [1,2]. Here, we show for the first time the importance of the temporal structure of the ionizing single attosecond pulse (i.e. attochirp) in the extraction of time delays in attosecond streaking experiments. We have demonstrated this by measuring the time delay between valence electrons from different atomic species by combining attosecond streaking with a coincidence detection scheme. This novel technique allows for the simultaneous measurement of both species under identical conditions. We find that the attochirp introduces an artificial time delay that may exceed the atomic time delay and present a general procedure, which corrects for this contribution. Our analysis, exemplarily applied to argon (Ar) and neon (Ne), reveals an energy-dependent atomic time delay of a few tens of attoseconds in agreement with theoretical predictions.

Sabbar, M; Boge, R; Lucchini, M; Gallmann, L; Cirelli, C; Keller, U

2014-01-01

284

Effects of diabatic heating on the ageostrophic circulation of an upper tropospheric jet streak  

NASA Technical Reports Server (NTRS)

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.

Keyser, D. A.; Johnson, D. R.

1982-01-01

285

An approach for megahertz OCT: streak mode Fourier domain optical coherence tomography  

NASA Astrophysics Data System (ADS)

We report a technique, which uses an area-scan camera to record the interference spectrum. Traditional point-scanning is remained in this streak-mode FDOCT so that the small aperture of the single-mode fiber functions as a confocal gate and screens multiply scattered photons very well. While the sample beam is scanning the specimen laterally, the interference spectrum is physically scanned on the area scan camera using a streak scanner. Therefore, pixels of the camera are illuminated by the spectrum of OCT signal row by row, corresponding to each A-scan at different lateral position. A unidirectional B-scan of 700 lines is obtained in 1 ms; thus, an A-scan time of 1.4 ?s is achieved. A Day 4 chick embryo sampled is imaged using this method. This technique is highly potential for multi-Megahertz OCT imaging.

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

2011-03-01

286

4D imaging of embryonic chick hearts by streak-mode Fourier domain optical coherence tomography  

NASA Astrophysics Data System (ADS)

Recently, we developed the streak-mode Fourier domain optical coherence tomography (OCT) technique in which an area-scan camera is used in a streak-mode to record the OCT spectrum. Here we report the application of this technique to in ovo imaging HH18 embryonic chick hearts with an ultrahigh speed of 1,016,000 axial scans per second. The high-scan rate enables the acquisition of high temporal resolution 2D datasets (1,000 frames per second or 1 ms between frames) and 3D datasets (10 volumes per second), without use of prospective or retrospective gating technique. This marks the first time that the embryonic animal heart has been 4D imaged using a megahertz OCT.

Wang, Rui; Yun, Julie X.; Goodwin, Richard; Markwald, Roger; Borg, Thomas K.; Runyan, Raymond B.; Gao, Bruce

2012-02-01

287

Single-Shot Visualization of Evolving Laser Wakefields Using an All-Optical Streak Camera  

NASA Astrophysics Data System (ADS)

We visualize ps-time-scale evolution of an electron density bubble—a wake structure created in atmospheric density plasma by an intense ultrashort laser pulse—from the phase "streak" that the bubble imprints onto a probe pulse that crosses its path obliquely. Phase streaks, recovered in one shot using frequency-domain interferometric techniques, reveal the formation, propagation, and coalescence of the bubble within a 3 mm long ionized helium gas target. 3D particle-in-cell simulations validate the observed density-dependent bubble evolution, and correlate it with the generation of a quasimonoenergetic ˜100 MeV electron beam. The results provide a basis for understanding optimized electron acceleration at a plasma density ne?2×1019 cm-3, inefficient acceleration at lower density, and dephasing limits at higher density.

Li, Zhengyan; Tsai, Hai-En; Zhang, Xi; Pai, Chih-Hao; Chang, Yen-Yu; Zgadzaj, Rafal; Wang, Xiaoming; Khudik, V.; Shvets, G.; Downer, M. C.

2014-08-01

288

Streaked radiography of an irradiated foam sample on the National Ignition Facility  

NASA Astrophysics Data System (ADS)

Streaked x-ray radiography images of annular patterns in an evolving tantalum oxide foam under the influence of a driven, subsonic radiation wave were obtained on the National Ignition Facility. This is the first successful radiography measurement of the evolution of well-defined foam features under a driven, subsonic wave in the diffusive regime. A continuous record of the evolution was recorded on an x-ray streak camera, using a slot-apertured point-projection backlighter with an 8 ns nickel source (7.9 keV). Radiography images were obtained for four different annular patterns, which were corrected using a source-dependent flat-field image. The evolution of the foam features was well-modeled using the 3D KULL radiation hydrodynamics code. This experimental and modeling platform can be modified for scaled high-energy-density laboratory astrophysics experiments.

Cooper, A. B. R.; Schneider, M. B.; MacLaren, S. A.; Moore, A. S.; Young, P. E.; Hsing, W. W.; Seugling, R.; Foord, M. E.; Sain, J. D.; May, M. J.; Marrs, R. E.; Maddox, B. R.; Lu, K.; Dodson, K.; Smalyuk, V.; Graham, P.; Foster, J. M.; Back, C. A.; Hund, J. F.

2013-03-01

289

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

PubMed

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. PMID:19044647

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

2008-10-01

290

Time-resolved X-ray excited optical luminescence using an optical streak camera  

NASA Astrophysics Data System (ADS)

We report the development of a time-resolved XEOL (TR-XEOL) system that employs an optical streak camera. We have conducted TR-XEOL experiments at the Canadian Light Source (CLS) operating in single bunch mode with a 570 ns dark gap and 35 ps electron bunch pulse, and at the Advanced Photon Source (APS) operating in top-up mode with a 153 ns dark gap and 33.5 ps electron bunch pulse. To illustrate the power of this technique we measured the TR-XEOL of solid-solution nanopowders of gallium nitride - zinc oxide, and for the first time have been able to resolve near-band-gap (NBG) optical luminescence emission from these materials. Herein we will discuss the development of the streak camera TR-XEOL technique and its application to the study of these novel materials.

Ward, M. J.; Regier, T. Z.; Vogt, J. M.; Gordon, R. A.; Han, W.-Q.; Sham, T. K.

2013-03-01

291

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

PubMed

A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially Czerny-Turner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments. PMID:21034059

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

2010-10-01

292

Dynamical image-charge effects in attosecond time-resolved streaked photoelectron spectra of metal surfaces  

NASA Astrophysics Data System (ADS)

The release of conduction-band electrons from a metal surface by a sub-femtosecond extreme ultraviolet (XUV) pulse, and their propagation through and near the solid [1], provokes a dielectric response in the solid that acts back on the photoelectron wave packet. We calculated the (wake) potential associated with this photoelectron self-interaction in terms of bulk and surface plasmon excitations and show that it induces a considerable, XUV-frequency-dependent temporal shift in laser-streaked XUV-photoemission spectra [2], suggesting the observation of the ultrafast solid-state dielectric response in contemporary streaked photoemission experiments. [4pt] [1] C.-H. Zhang and U. Thumm, Phys. Rev. Lett. 102, 123601(2009); Phys. Rev. A 80, 032902 (2009).[0pt] [2] C.-H. Zhang and U. Thumm, Phys. Rev. A 82, 043405(2010).

Zhang, Chang-Hua; Thumm, Uwe

2011-06-01

293

Simulating Record Accomplishments in Baseball Or, That's the Second-Biggest Hitting Streak I've Ever Seen  

Microsoft Academic Search

Simulations of baseball history have been presented as a means of demonstrat- ing the degree of exceptionality of certain feats in the game, notably the 56-game hitting streak of Joe DiMaggio and the less-celebrated 84-game on base streak by Ted Williams. These simulations typically ignore regression to the mean in their estimates of true ability, and do not verify other

Andrew C. Thomas

294

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

PubMed Central

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 establish a novel paradigm for investigating the fetal/placental relationship. PMID:19191225

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

2010-01-01

295

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

PubMed

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. PMID:23566871

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

2013-05-01

296

Hepatopetal collaterals after portal vein thrombosis following liver transplantation  

Microsoft Academic Search

Two liver transplant patients with hepatopetal collaterals after portal vein thrombosis are described. Angiographically, the\\u000a appearance is similar to cavernous transformation of the portal vein. The demonstration of hepatopetal collaterals is diagnosic\\u000a of portal vein occlusion from whatever cause. After portal vein occlusion, collaterals develop from preexisting periportal\\u000a vessels which undergo compensatory enlargement and reconstitute the intraheptic portal vessels. In

Albert B. Zajko; Klaus M. Bron

1986-01-01

297

Comparison of cesium iodide and gold photocathodes for x-ray streak cameras  

Microsoft Academic Search

X-ray streak cameras at Lawrence Livermore Laboratory use gold transmission photocathodes for x-ray detection. Other photocathode materials which might provide improved sensitivity without loss of temporal resolution are of interest. Of particular interest are dielectrics such as cesium iodide. Simultaneous measurements of the sensitivity to 500 eV x-rays of both gold and cesium iodide photocathodes in the LLL Soft X-ray

G. L. Stradling; H. Medecki; D. T. Attwood; R. L. Kauffman; B. L. Henke

1979-01-01

298

Integration of Banana Streak Badnavirus into the MusaGenome: Molecular and Cytogenetic Evidence  

Microsoft Academic Search

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 andMusasequences and a complex

Glyn Harper; Julian O. Osuji; Roger Hull

1999-01-01

299

Improvements in avalanche-transistor sweep circuitry for electro-optic streak cameras  

Microsoft Academic Search

The authors have improved the performance of the avalanche-transistor deflector-driver (sweep) circuitry used in the high-speed, electro-optic streak camera at Lawrence Livermore National Laboratory. In the previous design for the sweep circuit, trigger-to-output delay time drifted on some cameras. This delay drift is a function of a somewhat randomly unstable breakdown voltage of some avalanche transistors. Both temperature and differences

S. W. Thomas; R. L. Griffith; W. R. McDonald

1986-01-01

300

Comparison of lightning flash rates from the PBE sensor and streak counting from the DMSP satellite  

Microsoft Academic Search

A comparison of lightning trigger rates from the PBE sensor and streaks recorded by the accompanying optical scanner provides a calibration between these two lightning detection techniques. From this calibration is inferred the areal sensitivity of the optical scanner for lightning detection (2.6 x 10⁴ km²). Lightning flash density can be calculated from equations 9 and 10, and global flash

Turman

1984-01-01

301

Signs of the principle body axes prior to primitive streak formation in the rabbit embryo  

Microsoft Academic Search

An early common element during anterior-posterior axis formation amongst amniotes is the primitive streak, running longitudinally in the two-layered embryonic disc. In mammals the primordium of this transient structure is the first definite morphological sign of the anterior-posterior axis, while in avian embryos the axis is visible and apparently defined earlier. Here we scrutinize suggestions that in mammals also there

Christoph Viebahn; Barbara Mayer; Martin Hrabé Angelis

1995-01-01

302

Complete Genome Sequence of an Emerging Genotype of Tobacco Streak Virus in the United States  

PubMed Central

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

Padmanabhan, Chellappan; Gao, Shan; Li, Rugang; Zhang, Shouan; Fei, Zhangjun

2014-01-01

303

Portal vein absence and nodular regenerative hyperplasiaof the liver with giant inferior mesenteric vein  

Microsoft Academic Search

.   We present a patient with nodular regenerative hyperplasia of the liver (NRH) and portal vein absence studied with CT, MR\\u000a imaging, and MR angiography. The most striking feature was exuberant hemorrhoids due to a giant hepatofugal inferior mesenteric\\u000a vein. A relationship between unbalanced portal blood flow and nodular regenerative transformation of the liver is suggested\\u000a in this patient.

E. Arana; L. Martí-Bonmatí; V. Martínez; M. Hoyos; H. Montes

1997-01-01

304

Pulsed Doppler duplex sonography and CT of portal vein thrombosis  

Microsoft Academic Search

Five patients with partial or complete portal vein thrombosis were examined by both computed tomography (CT) and pulsed Doppler duplex scanning. Duplex scanning correctly identified portal vein thrombosis in all five. Duplex sonography may be the preferred technique to detect and follow portal vein thrombosis because of lower cost, lack of need for intravenous contrast material, and easier availability for

Valerie E. Miller; Lincoln L. Berland

1985-01-01

305

Long-term assessment of cryopreserved vein bypass grafting success  

Microsoft Academic Search

Purpose: When autogenous vein is unavailable, cryopreserved veins have been used in patients as a means of attempted limb salvage. We evaluated the long-term patency and limb salvage rates for patients undergoing bypass grafting with cryopreserved veins. Methods: Medical records were reviewed for patients undergoing cryovein bypass grafting at two hospitals from 1992 to 1997. Follow-up data were obtained from

Linda Harris; Monica O'Brien-Irr; John J. Ricotta

2001-01-01

306

Axial Length and Refraction in Retinal Vein Occlusions  

Microsoft Academic Search

To assess whether axial length and refraction are risk factors for retinal vein occlusion, we measured these parameters in 88 consecutive patients with unilateral branch retinal vein occlusion (BRVO), in 58 consecutive patients with unilateral central retinal vein occlusion (CRVO) and in 50 patients selected as a control group. Patients and controls were free or affected by systemic or local

Francesco Bandello; Alessandra Tavola; Luisa Pierro; Giulio Modorati; Claudio Azzolini; Rosario Brancato

1998-01-01

307

Systemic diseases associated with various types of retinal vein occlusion  

Microsoft Academic Search

PURPOSE: To investigate systemic diseases associated with various types of retinal vein occlusion.METHODS: We investigated prospectively in 1090 consecutive patients with retinal vein occlusion, almost all Caucasian (consistent with the racial pattern here), the prevalence of associated systemic disorders before or at the onset of various types of retinal vein occlusion. The patients were categorized into six types of retinal

Sohan Singh Hayreh; Bridget Zimmerman; Mark J. McCarthy; Patricia Podhajsky

2001-01-01

308

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

DOEpatents

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.

Nilson, David G. (Oakland, CA); Campbell, E. Michael (Pleasanton, CA); MacGowan, Brian J. (Livermore, CA); Medecki, Hector (Livermore, CA)

1988-01-01

309

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

PubMed

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. PMID:23262622

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

310

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

PubMed

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

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

2014-06-24

311

Oct4 Is Required ~E7.5 for Proliferation in the Primitive Streak  

PubMed Central

Oct4 is a widely recognized pluripotency factor as it maintains Embryonic Stem (ES) cells in a pluripotent state, and, in vivo, prevents the inner cell mass (ICM) in murine embryos from differentiating into trophectoderm. However, its function in somatic tissue after this developmental stage is not well characterized. Using a tamoxifen-inducible Cre recombinase and floxed alleles of Oct4, we investigated the effect of depleting Oct4 in mouse embryos between the pre-streak and headfold stages, ?E6.0–E8.0, when Oct4 is found in dynamic patterns throughout the embryonic compartment of the mouse egg cylinder. We found that depletion of Oct4 ?E7.5 resulted in a severe phenotype, comprised of craniorachischisis, random heart tube orientation, failed turning, defective somitogenesis and posterior truncation. Unlike in ES cells, depletion of the pluripotency factors Sox2 and Oct4 after E7.0 does not phenocopy, suggesting that ?E7.5 Oct4 is required within a network that is altered relative to the pluripotency network. Oct4 is not required in extraembryonic tissue for these processes, but is required to maintain cell viability in the embryo and normal proliferation within the primitive streak. Impaired expansion of the primitive streak occurs coincident with Oct4 depletion ?E7.5 and precedes deficient convergent extension which contributes to several aspects of the phenotype. PMID:24244203

DeVeale, Brian; Brokhman, Irina; Mohseni, Paria; Babak, Tomas; Yoon, Charles; Lin, Anthony; Onishi, Kento; Tomilin, Alexey; Pevny, Larysa; Zandstra, Peter W.; Nagy, Andras; van der Kooy, Derek

2013-01-01

312

A compact UV timing fiducial system for use with x-ray streak cameras at NIF  

NASA Astrophysics Data System (ADS)

We present the design of a compact UV (263-nm) timing fiducial system for use with x-ray streak cameras at the National Ignition Facility (NIF). The design consists of remote fiber amplification of an infrared 1053-nm (1?) seed, a free-space optical path that has two stages of frequency conversion from 1? to the fourth harmonic (4?), and fiber delivery of the 4? signal via output fiber for use with an x-ray streak camera. This is all contained within an airbox that can reside in a vacuum. The 1? seed and the pump light for the fiber amplifier is delivered to the airbox via optical fiber ( 100 meters) from a location in the NIF that is shielded from neutron radiation generated from imploding targets during system shots. When complete, the system will be able to provide timing fiducials to multiple x-ray streak cameras on the same system shot. We will present data that demonstrates end-to-end system performance.*

Homoelle, Doug; Bowers, Mark; Browning, Don; Burns, Scott; Erbert, Gaylen; Golick, Brad; Haley, Jim; McCarville, Tom; Opachich, Yekaterina; Padilla, Ernesto; Palmer, Nathan; Perfect, Brad; Pelz, Larry; Spinka, Tom; Throop, Alan; Wong, J. Nan

2012-10-01

313

Femtosecond streaking of electron diffraction patterns to study structural dynamics in crystalline matter  

NASA Astrophysics Data System (ADS)

A table-top femtosecond, non-relativistic, electron diffraction setup is combined with a low-jitter, photo-triggered streak camera to follow the optically induced structural dynamics in complex solids. A temporal resolution of 550 fs is experimentally demonstrated, while the route to streaking with sub-250 fs temporal resolution is outlined. The streaking technique allows for parallel capturing of temporal information as opposed to the serial data acquisition in a conventional scanning femtosecond electron diffraction. Moreover, its temporal resolution is not corrupted by increasing the number of electrons per pulse. Thus, compared to the conventional scanning approach, a substantial increase in signal-to-noise ratio (SNR) can be achieved. These benefits are demonstrated by studying a photo-induced charge density wave phase transition in 4Hb-TaSe2 using both methods. Within the same data acquisition time a three-fold increase in SNR is achieved when compared to the scanning method, with ways for a further improvement outlined.

Eichberger, M.; Erasmus, N.; Haupt, K.; Kassier, G.; von Flotow, A.; Demsar, J.; Schwoerer, H.

2013-03-01

314

Biological and Genomic Sequence Characterization of Maize streak virus Isolates from Wheat.  

PubMed

ABSTRACT Maize streak virus (MSV) is best known as the causal agent of maize streak disease. However, only a genetically uniform subset of the viruses within this diverse species is actually capable of producing severe symptoms in maize. Whereas these "maize-type" viruses all share greater than 95% sequence identity, MSV strains isolated from grasses may share as little as 79% sequence identity with the maize-type viruses. Here, we present the complete genome sequences and biological characterization of two MSV isolates from wheat that share approximately 89% sequence identity with the maize-type viruses. Clonal populations of these two isolates, named MSV-Tas and MSV-VW, were leafhopper-transmitted to Digitaria sanguinalis and a range of maize, wheat, and barley genotypes. Whereas the two viruses showed some differences in their pathogenicity in maize, they were both equally pathogenic in D. sanguinalis and the various wheat and barley genotypes tested. Phylogenetic analyses involving the genome sequences of MSV-Tas and MSV-VW, a new maize-type virus also fully sequenced in this study (MSV-VM), and all other available African streak virus sequences, indicated that MSV-Tas and MSV-VW are close relatives that together represent a distinct MSV strain. Sequence analyses revealed that MSV-VM has a recombinant genome containing MSV-Tas/VW-like sequences within its movement protein gene. PMID:18944143

Willment, J A; Martin, D P; Van der Walt, E; Rybicki, E P

2002-01-01

315

Isolated Left-sided Scimitar Vein Connecting All Left Pulmonary Veins to the Right Inferior Vena Cava  

Microsoft Academic Search

When the common pulmonary vein fails to develop, the embryonic connections of the pulmonary veins to one or more of the systemic\\u000a veins almost always persist. Anomalous pulmonary venous connections to the inferior vena cava (IVC) are typically characterized\\u000a by hypoplasia of the involved pulmonary veins and pulmonary artery, as well as abnormal parenchyma of the involved lung. Such\\u000a cases

A. L. Juraszek; H. Cohn; R. Van Praagh; S. Van Praagh

2005-01-01

316

Ophthalmodynamometric assessment of the central retinal vein collapse pressure in eyes with retinal vein stasis or occlusion  

Microsoft Academic Search

Purpose. Using a new Goldmann contact lens associated ophthalmodynamometric device, it was the purpose of the present study to determine the central retinal vein collapse pressure in eyes with retinal vein occlusions or retinal venous stasis.Methods. The prospective clinical non-interventional comparative study included 19 patients with central retinal vein occlusion (n=8), branch retinal vein occlusion (n=4), or retinal venous stasis

Jost B. Jonas

2003-01-01

317

Complete genome sequence of a new begomovirus associated with yellow mosaic disease of Hemidesmus indicus in India.  

PubMed

The complete DNA A genome of a virus isolate associated with yellow mosaic disease of a medicinal plant, Hemidesmus indicus, from India was cloned and sequenced. The length of DNA A was 2825 nucleotides, 35 nucleotides longer than the unit genome of monopartite begomoviruses. Comparison of the nucleotide sequence of DNA A of the virus isolate with those of other begomoviruses showed maximum sequence identity of 69 % to DNA A of ageratum yellow vein China virus (AYVCNV; AJ558120) and 68 % with tomato yellow leaf curl virus- LBa4 (TYLCV; EF185318), and it formed a distinct clade in phylogenetic analysis. The genome organization of the present virus isolate was found to be similar to that of Old World monopartite begomoviruses. The genome was considered to be monopartite, because association of DNA B and ? satellite DNA components was not detected. Based on its sequence identity (<70 %) to all other begomoviruses known to date and ICTV (International Committee on Taxonomy of Viruses) species demarcating criteria (<89 % identity), it is considered a member of a novel begomovirus species, and the tentative name "Hemidesmus yellow mosaic virus" (HeYMV) is proposed. PMID:24276235

Reddy, M Sreekanth; Kanakala, S; Srinivas, K P; Hema, M; Malathi, V G; Sreenivasulu, P

2014-05-01

318

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein  

PubMed Central

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart. PMID:25379351

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

319

Transcutaneous laser treatment of leg veins.  

PubMed

Leg telangiectasias and reticular veins are a common complaint affecting more than 80% of the population to some extent. To date, the gold standard remains sclerotherapy for most patients. However, there may be some specific situations, where sclerotherapy is contraindicated such as needle phobia, allergy to certain sclerosing agents, and the presence of vessels smaller than the diameter of a 30-gauge needle (including telangiectatic matting). In these cases, transcutaneous laser therapy is a valuable alternative. Currently, different laser modalities have been proposed for the management of leg veins. The aim of this article is to present an overview of the basic principles of transcutaneous laser therapy of leg veins and to review the existing literature on this subject, including the most recent developments. The 532-nm potassium titanyl phosphate (KTP) laser, the 585-600-nm pulsed dye laser, the 755-nm alexandrite laser, various 800-983-nm diode lasers, and the 1,064-nm neodymium yttrium-aluminum-garnet (Nd:YAG) laser and various intense pulsed light sources have been investigated for this indication. The KTP and pulsed dye laser are an effective treatment option for small vessels (<1 mm). The side effect profile is usually favorable to that of longer wavelength modalities. For larger veins, the use of a longer wavelength is required. According to the scarce evidence available, the Nd:YAG laser produces better clinical results than the alexandrite and diode laser. Penetration depth is high, whereas absorption by melanin is low, making the Nd:YAG laser suitable for the treatment of larger and deeply located veins and for the treatment of patients with dark skin types. Clinical outcome of Nd:YAG laser therapy approximates that of sclerotherapy, although the latter is associated with less pain. New developments include (1) the use of a nonuniform pulse sequence or a dual-wavelength modality, inducing methemoglobin formation and enhancing the optical absorption properties of the target structure, (2) pulse stacking and multiple pass laser treatment, (3) combination of laser therapy with sclerotherapy or radiofrequency, and (4) indocyanin green enhanced laser therapy. Future studies will have to confirm the role of these developments in the treatment of leg veins. The literature still lacks double-blind controlled clinical trials comparing the different laser modalities with each other and with sclerotherapy. Such trials should be the focus of future research. PMID:24220848

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

2014-03-01

320

Comprehensive Management of Subclavian Vein Effort Thrombosis  

PubMed Central

Subclavian vein (SCV) effort thrombosis, also known as the Paget-Schroetter syndrome, is a relatively uncommon condition that affects young, active, otherwise healthy individuals. It is considered a form of thoracic outlet syndrome, arising as a consequence of compression and repetitive injury of the SCV between the first rib and the overlying clavicle, as well as the anterior scalene muscle, subclavius muscle, and costoclavicular ligament. Effort thrombosis is distinct from other forms of deep vein thrombosis with respect to pathophysiology, clinical presentation, and functional consequences, and it requires treatment considerations unique to effective management of thoracic outlet compression as well as the obstructed SCV. In this review the comprehensive management of SCV effort thrombosis is addressed, with an emphasis on current interventional radiology techniques used in conjunction with definitive surgical treatment, based on early catheter-based venography, thrombolytic therapy, and prompt paraclavicular thoracic outlet decompression with direct SCV reconstruction. PMID:23448848

Thompson, Robert W.

2012-01-01

321

Electroretinography in central retinal vein occlusion  

Microsoft Academic Search

In 149 eyes with central retinal vein occlusion (CRVO), we prospectively investigated the role of routine, clinical electroretinography (ERG) in differentiating ischemic (60 eyes) from nonischemic CRVO (89 eyes). Single-flash photopic and scotopic ERGs were recorded. Data for the amplitudes and implicit times of a- and b-waves and for the b-\\/a-wave amplitude ratio were analyzed in detail. The study revealed

Sohan Singh Hayreh; Marie R. Klugman; Patricia Podhajsky; Hansjoerg E. Kolder

1989-01-01

322

Yellow nail syndrome: a rarity in Indians?  

PubMed

Reports of yellow nail syndrome have been few and far between. The classical triad of the syndrome has not been reported in Indian literature. We report a case of yellow nail syndrome in a forty-year-old male, who had yellowish-brown nails from birth. He developed lymphoedema of the legs at the age of twenty years and presented with pleural effusion at the age of forty years. Although a case of yellow nail syndrome has been reported from India, the classical triad of the syndrome is yet to be documented from our country. The condition may be missed because of the long time difference in presentation of different components of the syndrome and also because of the dark skin colour of Indians. PMID:16892747

Nair, V K; Sukumaran, P

1996-01-01

323

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

SciTech Connect

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

Qiao, J.; Jaanimagi, P. A.; Boni, R.; Bromage, J.; Hill, E. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)] [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)

2013-07-15

324

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

NASA Astrophysics Data System (ADS)

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

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

2013-07-01

325

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

PubMed

Short-pulse measurements using a streak camera are sensitive to space-charge broadening, which depends on the pulse duration and shape, and on the uniformity of photocathode illumination. An anamorphic-diffuser-based beam-homogenizing system and a space-charge-broadening calibration method were developed to accurately measure short pulses using an optical streak camera. This approach provides a more-uniform streak image and enables one to characterize space-charge-induced pulse-broadening effects. PMID:23902041

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

2013-07-01

326

Retrospective Comparison of Clinical Outcomes between Endovenous Laser and Saphenous Vein-sparing Surgery for Treatment of Varicose Veins  

Microsoft Academic Search

Background  The purpose of the present study was to compare management of varicose veins by endovenous laser ablation (EVL) and a vein-sparing\\u000a procedure (CHIVA: Conservatrice et Hémodynamique de l’Insuffisance Veineuse en Ambulatoire) for management of varicose veins.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Data from 82 consecutive patients with great saphenous vein (GSV) reflux and primary varicose veins presenting to the vascular\\u000a clinic at the Far Eastern

Chih-Yang Chan; Tzu-Chun Chen; Yung-Kun Hsieh; Jih-Hsin Huang

327

Percutaneous Transumbilical Portal Vein Embolization in a Patient with a Ruptured Hepatocellular Carcinoma Supplied by the Portal Vein  

SciTech Connect

We describe a case of a ruptured hepatocellular carcinoma supplied by the portal vein that was successfully treated with portal vein embolization via a percutaneous transumbilical approach. A contrast material-enhanced computed tomographic (CT) scan showed the presence of a large hypervascular tumor on portal venous phase as well as right hepatic vein thrombosis and hemoperitoneum that prevented portal vein embolization by the use of the percutaneous and transjugular transhepatic approach. The use of percutaneous transumbilical portal vein embolization can be an alternative option in this situation.

Kim, Soo Chin; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Chung, Jin Wook; Jae, Hwan Jun; Park, Jae Hyung [Seoul National University College of Medicine, Department of Radiology (Korea, Republic of)

2011-02-15

328

Fundus Autofluorescence and Optical Coherence Tomography Findings in Branch Retinal Vein Occlusion  

PubMed Central

Purpose. To describe the findings of fundus autofluorescence (FAF) and optical coherence tomography (OCT) in patients with branch retinal vein occlusion (BRVO). Methods. In this institutional, retrospective, observational case series, FAF was evaluated in 65 eyes with BRVO in 64 consecutive patients and compared with visual acuity, OCT findings, and other clinical observations. Results. Five types of autofluorescence appeared during the course of BRVO: (1) petaloid-shaped hyperautofluorescence in the area of macular edema and (2) hyperautofluorescence coincident with yellow subretinal deposits. (3) Diffuse hyperautofluorescence appeared within the area of serous retinal detachment (SRD) and OCT showed precipitates on the undersurface of the retina in 5/5 of these eyes (100%). (4) The area of vein occlusion showed diffuse hyperautofluorescence after resolution of the retinal bleeding. (5) Hard exudates exhibited hyper- or hypoautofluorescence. OCT indicated that most of the hard exudates with hyperautofluorescence were located on the retinal pigment epithelium. Conclusions. Hyperautofluorescence associated with subretinal fluid or hard exudate appeared in the subretinal space. This type of hyperautofluorescence may be attributed to blood cell or macrophages. FAF and OCT are noninvasive modalities that provide additional information regarding macular edema due to BRVO. PMID:23209881

Sekiryu, Tetsuju; Iida, Tomohiro; Sakai, Eiichi; Maruko, Ichiro; Ojima, Akira; Sugano, Yukinori

2012-01-01

329

Metabolic effects of portal vein sensing.  

PubMed

The extrinsic gastrointestinal nerves are crucial in the sensing of nutrients and hormones and its translation in terms of control of food intake. Major macronutrients like glucose and protein are sensed by the extrinsic nerves located in the portal vein walls, which signal to the brain and account for the satiety phenomenon they promote. Glucose is sensed in the portal vein by neurons expressing the glucose receptor SGLT3, which activate the main regions of the brain involved in the control of food intake. Proteins indirectly act on food intake by inducing intestinal gluconeogenesis and its sensing by the portal glucose sensor. The mechanism involves a prior antagonism by peptides of the ?-opioid receptors present in the portal vein nervous system and a reflex arc with the brain inducing intestinal gluconeogenesis. In a comparable manner, short-chain fatty acids produced from soluble fibre act via intestinal gluconeogenesis to exert anti-obesity and anti-diabetic effects. In the case of propionate, the mechanism involves a prior activation of the free fatty acid receptor FFAR3 present in the portal nerves and a reflex arc initiating intestinal gluconeogenesis. PMID:25200297

Mithieux, G

2014-09-01

330

[Recurrent varicose veins. Surgical procedure--results].  

PubMed

We report 96 patients (107 legs) with recurrence after varicose vein surgery. We define a recurrent varicose vein as a new transfascial insufficiency after incomplete interruption of the saphenofemoral as well as popliteal junction with reflux in the epifascial venous system. 92 patients underwent external primary surgery. Morphologically an insufficient high ligation of the V. saphena magna (Moszkowicz's operation) led in 30 cases to a recurrent varicose vein. In 47 cases an incomplete isolated, in 29 cases an incomplete saphenofemoral ligation during a Babcock procedure and in one case an incomplete saphenopopliteal ligation for V. saphena parva insufficiency were the reasons for the recurrence. As recurrent surgery we performed 106 ligations of the saphenofemoral junction. In 38 of these cases an isolated saphenofemoral ligation and in 68 cases an additional stage-adjusted ligation of the V. saphena magna were carried out. In one case of recurrent saphenopopliteal insufficiency a repeated ligation of the V. saphena parva was performed. The recurrence is an avoidable complication of a not perfect primary surgery. The main cause is an inadequate access with incomplete saphenofemoral or -popliteal ligation. PMID:11503464

Pourhassan, S; Zarras, K; Mackrodt, H G; Stock, W

2001-07-01

331

Conditions for veining in the Barrandian Basin (Lower Palaeozoic), Czech Republic: evidence from fluid inclusion and apatite fission track analysis  

NASA Astrophysics Data System (ADS)

The interplay between fracture propagation and fluid composition and circulation has been examined by deciphering vein sequences in Silurian and Devonian limestones and shales at Kosov quarry in the Barrandian Basin. Three successive vein generations were recognised that can be attributed to different stages of a basinal cycle. Almost all generations of fracture cements host abundant liquid hydrocarbon inclusions that indicate repeated episodes of petroleum migration through the strata during burial, tectonic compression and uplift. The earliest veins that propagated prior to folding were displacive fibrous "beef" calcite veins occurring parallel to the bedding of some shale beds. Hydrocarbon inclusions within calcite possess homogenisation temperatures between 58 and 68 °C and show that the "beef" calcites originated in the deeper burial environment, during early petroleum migration from overpressured shales. E-W-striking extension veins that postdate "beef" calcite formed in response to Variscan orogenic deformations. Based on apatite fission track analysis (AFTA) data and other geological evidence, the veins probably formed 380-315 Ma ago, roughly coinciding with peak burial heating of the strata, folding and the intrusion of Variscan synorogenic granites. The veins that crosscut diagenetic cements and low-amplitude stylolites in host limestones are oriented semi-vertically to the bedding plane and are filled with cloudy, twinned calcite, idiomorphic smoky quartz and residues of hardened bitumen. Calcite and quartz cements contain abundant blue and blue-green-fluorescing primary inclusions of liquid hydrocarbons that homogenise between 50 and 110 °C. Geochemical characteristics of the fluids as revealed by gas chromatography-mass spectrometry, particularly the presence of olefins and parent aromatic hydrocarbons (phenonthrene), suggest that the oil entrapped in the inclusions experienced intense but geologically fast heating that resulted in thermal pyrolysis of its hydrocarbons. This implies that the organic fluids in the fractures may have been partly influenced by heating associated with igneous intrusions that are hidden below the surface. Subvertical N-S-striking veins represent the most recent fracturing event(s). Some of these veins are only a few millimeters thick and sparsely mineralised with thin leaf-like quartz crystals that contain tiny blue and yellow-orange-fluorescing hydrocarbon inclusions. Most of the N-S veins, however, occur as thick calcite veins that generally crystallised at 70 °C or less from H 2O-NaCl solutions of variable salinity with admixture of petroleum. The origin of these fluids is interpreted in terms of deeply circulating meteoric waters that partially mixed with deep basinal fluids. Wider structural considerations combined with fission-track analysis of adjacent host sediments suggest that N-S veins formed during post-Mesozoic uplift of the area, probably in response to major Tertiary Alpine deformations transmitted far into the Bohemian Massif.

Suchy, V.; Dobes, P.; Filip, J.; Stejskal, M.; Zeman, A.

2002-04-01

332

Habitat Suitability Index Models: Yellow Perch  

USGS Publications Warehouse

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.

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

1983-01-01

333

Yellow fever vaccine-associated viscerotropic disease.  

PubMed

Yellow fever is a mosquito-transmitted hemorrhagic viral disease that is endemic to tropical regions in South America and Africa. It remains a significant health concern for deploying military personnel, accordingly vaccination is frequently performed on troops. Although the vaccine is generally administered with only minor complications, rare severe complications are also reported. Herein, we report a mild case of yellow fever vaccine-associated viscerotropic disease 4 days after administration of the vaccine. The various complications of the vaccine and their pathogenesis are also reviewed. PMID:22594140

Rowland, Michael; Plackett, Timothy P; Smith, Richard

2012-04-01

334

Hepatectomy With Portal Vein Resection for Hilar Cholangiocarcinoma  

PubMed Central

Objective: To better determine the role of portal vein resection and its effect on survival, as well as to appreciate the impact of portal vein invasion on prognosis in hilar cholangiocarcinoma. Summary Background Data: Hepatectomy with portal vein resection is sometimes performed for locally advanced hilar cholangiocarcinoma. However, the significance of microscopic invasion of the portal vein has not been determined. Methods: Medical records of 160 patients with hilar cholangiocarcinoma who underwent macroscopically curative hepatectomy with (n = 52) or without portal vein resection (n = 108) were reviewed. Invasion of the portal vein was assessed histologically on the surgical specimen, and results were correlated with clinicopathologic features and survival. Results: Surgical mortality, including all hospital deaths, was similar in patients who did and did not undergo portal vein resection (9.6% vs. 9.3%), but the primary tumor was more advanced in patients who underwent portal vein resection. Histologically, no invasion was found in 16 (30.8%) of resected portal veins. However, dense fibrosis adjacent to the portal vein was common, and the mean distance between the leading edge of cancer cells and the adventitia of the portal vein was 437 ± 431 ?m. The prognosis was worse in patients with than without portal vein resection (5-year survival, 9.9% vs. 36.8%; P < 0.0001). The presence or absence of microscopic invasion of the resected portal vein did not influence survival (16.6 months in patients with microscopic invasion vs. 19.4 months in those without; P = 0.1506). Multivariate analysis identified histologic differentiation, lymph node metastasis, and macroscopic portal vein invasion as independent prognostic factors. Conclusions: Microscopic invasion of the portal vein may be misdiagnosed clinically in patients with hilar cholangiocarcinoma. However, the distance between tumor and adventitia is so narrow that curative resection without portal vein resection is unlikely to be possible. Gross portal vein invasion has a negative impact on survival, and hepatectomy with portal vein resection can offer long-term survival in some patients with advanced hilar cholangiocarcinoma. PMID:14578735

Ebata, Tomoki; Nagino, Masato; Kamiya, Junichi; Uesaka, Katsuhiko; Nagasaka, Tetsuro; Nimura, Yuji

2003-01-01

335

Occlusion of azygos vein via direct percutaneous puncture of innominate vein following cavopulmonary anastomosis.  

PubMed

A 2-year-10-month-old boy was diagnosed with a complex congenital heart disease: right atrial isomerism, left superior vena cava (LSVC), complete atrioventricular septal defect, secundum type atrial septal defect, transposition of the great arteries with pulmonary atresia, patent ductus arteriosus, absence of a right superior vena cava (RSVC), and dextrocardia. He had received a left Blalock-Taussig (BT) shunt at the age of 3 months and a left bidirectional Glenn shunt one year after BT shunt. Progressive cyanosis was noted after the second operation and cardiac catheterization showed a functional Glenn shunt with an engorged azygos vein, which was inadvertently skipped for ligation. Because of the absence of RSVC, transcatheter occlusion of the azygos vein was performed successfully via direct puncture of the innominate vein. PMID:10850539

Chen, M R; Yang, F S

2000-03-01

336

Anomalous formation of external jugular vein and its clinical implication  

PubMed Central

Introduction: The superficial veins, especially the external jugular vein (EJV), are increasingly being utilized for cannulation to conduct diagnostic procedures or intravenous therapies. EJV is also used in microsurgical procedures,used as a recipient for the free flaps. Materials and Methods: During routine dissection a variation was observed in the formation of EJV unilaterally on the left side. Result: In the anterior triangle of the neck submandibular vein joined with the anterior jugular vein to form a large venous trunk (V1). Facial vein joined this venous trunk (V1) to form another common channel (V2). The retromandibular vein divided into unusually long anterior and posterior divisions. Anterior division did not join the facial vein but drained into the common channel V2.The posterior division of retromandibular vein also drained into V2 which further continued as EJV and drained into the subclavian vein. Conclusion: The knowledge of variations in the patterns of superficial veins is important for the surgeons to avoid any intraoperative error which might lead to unnecessary bleeding. PMID:22442610

Chauhan, Navneet Kumar; Rani, Archana; Chopra, Jyoti; Rani, Anita; Srivastava, A. K.; Kumar, Vijay

2011-01-01

337

Bedding parallel veins and their relationship to folding  

NASA Astrophysics Data System (ADS)

Laminated bedding parallel veins hosted in turbiditic sandstone shale sequences from central Victoria, Australia, consist of stacked, millimetre thick, sub-parallel sheets of quartz separated by micaceous layers, wall rock slivers and pressure solution seams. They have very high length to thickness ratios, are laterally continuous over tens to hundreds of metres, and have relatively uniform thickness compared to other vein types. They are intimately associated with and folded by chevron folds, and the quartz grain shape elongation lineation is commonly orthogonal to mesoscopic and macroscopic fold hinge lines. The bedding parallel veins have two morphological forms. Type I are thin (commonly 5-10 cm) laminated veins which have complex microstructures dominated by phyllosilicate inclusion surfaces, related to oblique opening along bedding with varying rates of deposition (opening) relative to shear displacement (slip) along the bedding surfaces. More common are Type II, thicker (generally <20 cm), banded veins of alternating milky-white quartz with wall rock inclusion laminae (formerly fragments) bounded by stylolitic partings parallel to both bedding and the vein margins. The inclusion surfaces in Type I veins track the opening direction during vein formation. Vein opening-sense criteria suggest cyclical pore fluid pressure fluctuations which predate the amplification and propagation of the host chevron folds; i.e. prior to attainment of significant limb dip. Different layer parallel shortening and amplification rates for individual layers within the sedimentary sequence may lead to bedding parallel veins with an opening sense unrelated to the flexural slip folds which eventually follow.

Jessell, M. W.; Willman, C. E.; Gray, D. R.

1994-06-01

338

YELLOW-BELLIED MARMOTS (MARMOTA FLAVIVENTRIS) HIBERNATE SOCIALLY  

E-print Network

YELLOW-BELLIED MARMOTS (MARMOTA FLAVIVENTRIS) HIBERNATE SOCIALLY DANIEL T. BLUMSTEIN,* SOYEON IM Marmota, Family Sciuridae), only 2, the woodchuck (M. monax) and yellow- bellied marmot (M. flaviventris patterns. Key words: climate change, evolution of sociality, Marmota flaviventris, social hibernation

Grether, Gregory

339

21 CFR 137.275 - Yellow corn meal.  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.275 Yellow corn meal. Yellow corn meal...

2012-04-01

340

21 CFR 137.275 - Yellow corn meal.  

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.275 Yellow corn meal. Yellow corn meal...

2014-04-01

341

21 CFR 137.280 - Bolted yellow corn meal.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow...

2013-04-01

342

21 CFR 137.275 - Yellow corn meal.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.275 Yellow corn meal. Yellow corn meal...

2013-04-01

343

21 CFR 137.280 - Bolted yellow corn meal.  

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow...

2014-04-01

344

21 CFR 137.280 - Bolted yellow corn meal.  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow...

2012-04-01

345

Comparative Genome Analysis of the Yellow Fever Mosquito Aedes aegypti  

E-print Network

Comparative Genome Analysis of the Yellow Fever Mosquito Aedes aegypti with Drosophila melanogaster aegypti, and Culex pipiens, the primary vectors for malaria, yellow fever and dengue, and lymphatic 103

Severson, David

346

Streak-photographic investigation of shock wave emission after laser-induced plasma formation in water  

NASA Astrophysics Data System (ADS)

The shock wave emission after dielectric breakdown in water was investigated to assess potential shock wave effects in plasma mediated tissue ablation and intraocular photodisruption. Of particular interest was the dependence of shock wave pressure as a function of distance from the plasma for different laser pulse energies. We have generated plasmas in water with a Nd:YAG laser system delivering pulses of 6 ns duration. The pulses, with energies between 0.4 and 36 mJ (approximately equals 180 times threshold), were focused into a cuvette containing distilled water. The shock wave was visualized with streak photography combined with a schlieren technique. An important advantage of this technique is that the shock position as a function of time can directly be obtained from a single streak and hence a single event. Other methods (e.g. flash photography or passage time measurements between fixed locations) in contrast rely on reproducible events. Using the shock wave speed obtained from the streak images, shock wave peak pressures were calculated providing detailed information on the propagation of the shock. The shock peak pressure as a function of distance r from the optical axis was found to decrease faster than 1/r2 in regions up to distances of 100-150 micrometers . For larger distances it was found to be roughly proportional to 1/r. The scaling law for maximum shock pressure p, at a given distance was found to be proportional to the square root of the laser pulse energy E for distances of 50-200 micrometers from the optical axis.

Noack, Joachim; Vogel, Alfred

1995-05-01

347

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

PubMed

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 ?m) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ("hotspot") was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/cm(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. PMID:22938275

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

2012-08-01

348

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

NASA Astrophysics Data System (ADS)

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 ?m) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ("hotspot") was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/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.

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

2012-08-01

349

A new tubeless nanosecond streak camera based on optical deflection and direct CCD imaging  

SciTech Connect

A new optically deflected streaking camera with performance of nanosecond-range resolution, superior imaging quality, high signal detectability, and large format recording has been conceived and developed. Its construction is composed of an optomechanical deflector that deflects the line-shape image of spatial-distributed time-varying signals across the sensing surface of a cooled scientific two-dimensional CCD array with slow readout driving electronics, a lens assembly, and a desk-top computer for prompt digital data acquisition and processing. Its development utilizes the synergism of modern technologies in sensor, optical deflector, optics and microcomputer. With laser light as signal carrier, the deflecting optics produces near diffraction-limited streak images resolving to a single pixel size of 25{mu}. A 1kx1k-pixel array can thus provide a vast record of 1,000 digital data points along each spatial or temporal axis. Since only one photon-to-electron conversion exists in the entire signal recording path, the camera responses linearly to the incident light over a wide dynamic range in excess of 10{sup 4}:1. Various image deflection techniques are assessed for imaging fidelity, deflection speed, and capacity for external triggering. Innovative multiple-pass deflection methods for utilizing optomechanical deflector have been conceived and developed to attain multi-fold amplification for the optical scanning. speed across the CCD surface at a given angular deflector speed. Without significantly compromising imaging. quality or flux throughput efficiency, these optical methods enable a sub-10 ns/pixel streak speed with the deflector moving benignly at 500 radians/second, or equivalently 80 revolutions /second. Test results of the prototype performance are summarized including a spatial resolution of 10 lp/mm at 65% CTF and a temporal resolution of 11.4 ns at 3.8 ns/pixel.

Lai, C.C.

1992-12-01

350

A new tubeless nanosecond streak camera based on optical deflection and direct CCD imaging  

SciTech Connect

A new optically deflected streaking camera with performance of nanosecond-range resolution, superior imaging quality, high signal detectability, and large format recording has been conceived and developed. Its construction is composed of an optomechanical deflector that deflects the line-shape image of spatial-distributed time-varying signals across the sensing surface of a cooled scientific two-dimensional CCD array with slow readout driving electronics, a lens assembly, and a desk-top computer for prompt digital data acquisition and processing. Its development utilizes the synergism of modern technologies in sensor, optical deflector, optics and microcomputer. With laser light as signal carrier, the deflecting optics produces near diffraction-limited streak images resolving to a single pixel size of 25[mu]. A 1kx1k-pixel array can thus provide a vast record of 1,000 digital data points along each spatial or temporal axis. Since only one photon-to-electron conversion exists in the entire signal recording path, the camera responses linearly to the incident light over a wide dynamic range in excess of 10[sup 4]:1. Various image deflection techniques are assessed for imaging fidelity, deflection speed, and capacity for external triggering. Innovative multiple-pass deflection methods for utilizing optomechanical deflector have been conceived and developed to attain multi-fold amplification for the optical scanning. speed across the CCD surface at a given angular deflector speed. Without significantly compromising imaging. quality or flux throughput efficiency, these optical methods enable a sub-10 ns/pixel streak speed with the deflector moving benignly at 500 radians/second, or equivalently 80 revolutions /second. Test results of the prototype performance are summarized including a spatial resolution of 10 lp/mm at 65% CTF and a temporal resolution of 11.4 ns at 3.8 ns/pixel.

Lai, C.C.

1992-12-01

351

Yellow-bellied marmots are generalist herbivores  

Microsoft Academic Search

Yellow-bellied marmots (Marmota flaviventris) eat a wide variety of grasses, forbs, and seeds, but do not feed on all items in proportion to their abundance in the environment. In this study, relationships between the marmot diet and estimated protein, water, caloric value, relative biomass, and toxicity of the available plant species were investigated. The epidermis of all forb species did

B. A. Frase; K. B. Armitage

1989-01-01

352

Cardiovascular effects of yellow oleander ingestion.  

PubMed

Yellow oleander (Thevetia neriifolia) is a commonly grown tree found widely in Eastern India. The seeds of yellow oleander are highly poisonous and contain three glycosides--thevetin, thevetoxin and peruvoside. Yellow oleander seed ingestion is usually with suicidal intent in Eastern India. Manifestations range from mild to potentially fatal. It has significant cardiovascular effects with varying rhythm abnormalities. Effects of yellow oleander seed ingestion (YOI) were studied in 300 patients from 1986 to 1990 at BS Medical College, Bankura. Majority i.e., 246 (82%) were females and 226 (75.33%) were young in the age group 11-20 years. Most reported for treatment 6 to 8 hours after ingestion of seeds. The number of seeds swallowed varied from half to fifteen. Two hundred and ninety-two (97.33%) ingested seeds in the crushed form; 156 (52%) were asymptomatic, 92 (30.66%) had vomiting and 36 (12%) had palpitation. In electrocardiogram (ECG), 138 (46%) revealed varying types of arrhythmias including sinus bradycardia in 68 cases (49.27%). Ischaemic changes were present in 118 cases (39.33%). Number of seeds ingested did not bear any relationship with ECG changes in YOI. All 14 cases of death were autopsied. Subendocardial and perivascular haemorrhage with focal myocardial oedema was present in all. Median hospital stay was 5 days (range 2 to 24). During discharge, 256 (85.33%) had normal ECG, 14 (4.66%) had sinus bradycardia and 16 (5.33%) demonstrated ischaemic changes. PMID:10638101

Bose, T K; Basu, R K; Biswas, B; De, J N; Majumdar, B C; Datta, S

1999-10-01

353

Lettuce necrotic yellows virus in New Zealand  

Microsoft Academic Search

Lettuce necrotic yellows virus, found in lettuce (Lactuca saliva L.) and sowthistle (Sonchus oleraceus L.) near Blenheim in 1965 caused severe losses in an Auckland lettuce crop in 1969. The virus was transmitted between S. oleraceus plants by the aphid Hyperomyzus lactucae L., which occurs throughout the year but is least plentiful during winter. Most infectivity in sap extracts was

P. R. Fry; R. C. Close; C. H. Procter; R. Sunde

1973-01-01

354

Volume III, Chapter 16 Yellow Warbler  

E-print Network

........................................................................................................... 16-1 16.2 Life History and Habitat Requirements; Sauer et al. 2003). 16.2 Life History and Habitat Requirements 16.2.1 Life History 16.2.1.1 Diet Yellow................................................................. 16-1 16.2.1 Life History

355

Phytoplankton and sediments in Yellow Sea  

NASA Technical Reports Server (NTRS)

Sediment and phytoplankton cloud the waters of the Yellow Sea in this true-color MODIS image acquired March 18, 2002. The swirls of sediment appear as a murky brownish blue color, while the phytoplankton are purely blue green and are concentrated around the small island in the lower right corner of the image.

2002-01-01

356

Vectors based on maize streak virus can replicate to high copy numbers in maize plants.  

PubMed

The genome of maize streak virus (MSV) consists of one molecule of circular, single-stranded DNA of 2.7 kb. A reporter gene (bar) coding for phosphinothricin acetyl-transferase was inserted into the small non-coding region of the MSV genome. The recombinant bar-containing MSV vectors were introduced into maize seedlings via agroinfection. The chimeric viral DNA was found to replicate to high copy numbers in maize leaves resistant to the application of the herbicide Basta. This establishes the usefulness of MSV as an efficient replicating vector in cells of maize plants. PMID:9049343

Shen, W H; Hohn, B

1995-04-01

357

Physics and roller coasters-The Blue Streak at Cedar Point  

NASA Astrophysics Data System (ADS)

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

Speers, Robert R.

1991-06-01

358

Frequency-domain streak camera for ultrafast imaging of evolving light-velocity objects.  

PubMed

We demonstrate a frequency-domain streak camera (FDSC) that captures the picosecond time evolution of luminal-velocity refractive index structures in a single shot. In our prototype FDSC, a probe-reference pulse pair propagates obliquely to a subpicosecond pump pulse that creates an evolving nonlinear index structure in glass, supplementing a conventional frequency-domain holographic probe-reference pair that copropagates with the pump. A single spectrometer acquires data from both pairs via spatial or temporal multiplexing, demonstrating the feasibility of a compact frequency-domain tomographic system in which a single spectrometer processes data from multiple probing angles. PMID:21165098

Li, Z; Zgadzaj, R; Wang, X; Reed, S; Dong, P; Downer, M C

2010-12-15

359

High resolution vidicon-based readout system for photon-counting streak camera applications  

NASA Technical Reports Server (NTRS)

The design, implementation, and evaluation of a high-resolution vidicon-based reconfigurable imaging system for integration into a photon-counting streak camera that can be readily coupled to a standard interface and computer have been achieved. Experimental results are reported which demonstrate that the design goals are met, providing the capability to measure differential time to better than 3 picosecond accuracy. Augmented by real-time calibration, the accuracy, linearity, noise levels, and stability of the system are adequate to support dual wavelength laser ranging.

Varghese, Thomas K.; Steggerda, Charles; Selden, Mike; Oldham, Thomas; Degnan, John J.

1992-01-01

360

Subpicosecond hard x-ray streak camera using single-photon counting.  

PubMed

We have developed and characterized a hard x-ray accumulating streak camera that achieves subpicosecond time resolution by using single-photon counting. A high repetition rate of 2 kHz was achieved by use of a readout camera with built-in image processing capabilities. The effects of sweep jitter were removed by using a UV timing reference. The use of single-photon counting allows the camera to reach a high quantum efficiency by not limiting the divergence of the photoelectrons. PMID:20890339

Enquist, Henrik; Navirian, Hengameh; Nüske, Ralf; von Korff Schmising, Clemens; Jurgilaitis, Andrius; Herzog, Marc; Bargheer, Matias; Sondhauss, Peter; Larsson, Jörgen

2010-10-01

361

Resolving the shape of a sonoluminescence pulse in sulfuric acid by the use of streak camera.  

PubMed

A streak camera is used to measure the shape of sonoluminescence pulses from a cavitation bubble levitated stably in a sulfuric acid solution. The shape and response to an acoustic pressure field of the sonoluminescence pulse in 85% by weight sulfuric acid are qualitatively similar to those in water. However, the pulse width in sulfuric acid is wider than that in water by over one order of magnitude. The width of the sonoluminescence pulse is strongly dependent on the concentration of the sulfuric acid solution, while the skewed distribution of the shape remains unchanged. PMID:19507941

Huang, Wei; Chen, Weizhong; Cui, Weicheng

2009-06-01

362

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

SciTech Connect

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

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

2005-08-21

363

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

SciTech Connect

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.

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

1981-02-01

364

Achieving 280 fs resolution with a streak camera by reducing the deflection dispersion  

SciTech Connect

The factors that limit the temporal resolution in a streak camera operating in an accumulative mode were studied. By controlling the timing jitter, the transit-time dispersion and the technical resolution of the camera on the order of 100 fs, the role of the deflection dispersion was investigated experimentally. It was done by changing the electron beam size in the deflection plates with a variable slit in front of the plates. The temporal resolution of the camera reached 280 fs when the slit width was a 5 {mu}m slit.

Shakya, Mahendra Man; Chang Zenghu [J.R. MacDonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)

2005-07-25

365

Characterization of complete genome and small RNA profile of pagoda yellow mosaic associated virus, a novel badnavirus in China.  

PubMed

A new badnavirus was discovered from pagoda trees showing yellow mosaic symptoms on the leaves by high throughput sequencing of small RNAs. The complete genome of this virus was determined to comprise 7424 nucleotides, and the virus shared 40.4-45.1% identity with that of other badnaviruses. The genome encodes five open reading frames (ORFs) on the plus strand, which includes three conserved badnaviral ORFs. These results suggest that this virus is a new member of the genus Badnavirus in the family Caulimoviridae. The virus is tentatively named pagoda yellow mosaic associated virus (PYMAV). Phylogenetic analysis suggested that this virus together with gooseberry vein banding virus (GVBV) and grapevine vein-clearing virus (GVCV) forms a separate group that is distinct two other well characterized badnaviral groups. Additionally, the viral derived small RNA (vsRNA) profile of PYMAV was analyzed and compared with that of viruses within the same family. Results showed that the most abundant PYMAV vsRNAs were 21-nt, whereas other viruses in the same family have a predominance of 22- or 24-nt vsRNA. The percentage of sense PYMAV vsRNA was almost equal to that of antisense vsRNA, whereas vsRNAs of other viruses in the family display preferences toward the sense strand of their genome. Furthermore, PYMAV vsRNAs were symmetrically distributed along the genome with no obvious vsRNA generating hotspots. PMID:24751798

Wang, Yilun; Cheng, Xiaofei; Wu, Xiaoxia; Wang, Aiming; Wu, Xiaoyun

2014-08-01

366

Evaluation of Three Egg Collection Techniques for Yellow Perch  

E-print Network

Evaluation of Three Egg Collection Techniques for Yellow Perch Matthew Ward, Todd St. Sauver, Dave Lucchesi, Bruce Johnson, Kevin Hoffman, and Jason Stahl #12;The yellow perch is a popular "panfish" among South Dakota anglers, supporting substantial summer and winter fisheries. #12;Yellow perch have a rather

367

Yellow (Perca flavescens) and Eurasian (P. fluviatilis) perch distinguished in  

E-print Network

292 Yellow (Perca flavescens) and Eurasian (P. fluviatilis) perch distinguished in fried fish to substitute Eurasian perch (P. fluviatilis Linnaeus) or some other species for yellow perch because of the decline of stocks of yellow perch in the Great Lakes and because of rising prices, both of which raise

368

21 CFR 573.1020 - Yellow prussiate of soda.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Yellow prussiate of soda. 573.1020 Section 573.1020 Food and Drugs...Additive Listing § 573.1020 Yellow prussiate of soda. Yellow prussiate of soda (sodium ferrocyanide decahydrate: Na4...

2010-04-01

369

21 CFR 573.1020 - Yellow prussiate of soda.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Yellow prussiate of soda. 573.1020 Section 573.1020 Food and Drugs...Additive Listing § 573.1020 Yellow prussiate of soda. Yellow prussiate of soda (sodium ferrocyanide decahydrate: Na4...

2011-04-01

370

Absorption of light by yellow substance in freshwater lakes  

Microsoft Academic Search

A spectrophotometric study was made of the absorption of light by yellow substance (gilvin, gelbstofl) in 12 freshwater lakes of diverse optical and biochemical character in which concen- trations of yellow substance ranged 50-fold. The shapes of the spectra of yellow substance absorp- tion, g,, suitably corrected for residual light scattering in the spectrophotometer, were well described by an exponential

R. J. DAVIES-COLLEY; W. N. VANT

1987-01-01

371

49 CFR 172.440 - RADIOACTIVE YELLOW-III label.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false RADIOACTIVE YELLOW-III label. 172.440...PLANS Labeling § 172.440 RADIOACTIVE YELLOW-III label. (a) Except for size and color, the RADIOACTIVE YELLOW-III label must be as...

2010-10-01

372

49 CFR 172.440 - RADIOACTIVE YELLOW-III label.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false RADIOACTIVE YELLOW-III label. 172.440...PLANS Labeling § 172.440 RADIOACTIVE YELLOW-III label. (a) Except for size and color, the RADIOACTIVE YELLOW-III label must be as...

2012-10-01

373

49 CFR 172.440 - RADIOACTIVE YELLOW-III label.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false RADIOACTIVE YELLOW-III label. 172.440...PLANS Labeling § 172.440 RADIOACTIVE YELLOW-III label. (a) Except for size and color, the RADIOACTIVE YELLOW-III label must be as...

2011-10-01

374

49 CFR 172.440 - RADIOACTIVE YELLOW-III label.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false RADIOACTIVE YELLOW-III label. 172.440...PLANS Labeling § 172.440 RADIOACTIVE YELLOW-III label. (a) Except for size and color, the RADIOACTIVE YELLOW-III label must be as...

2013-10-01

375

49 CFR 172.440 - RADIOACTIVE YELLOW-III label.  

...2014-10-01 2014-10-01 false RADIOACTIVE YELLOW-III label. 172.440...PLANS Labeling § 172.440 RADIOACTIVE YELLOW-III label. (a) Except for size and color, the RADIOACTIVE YELLOW-III label must be as...

2014-10-01

376

88—A SPECTROPHOTOMETRIC STUDY OF YELLOWING IN WOOL FABRIC  

Microsoft Academic Search

The differential spectrophotometric method of measuring colour in wool fabric reveals that the fabric yellows much more slowly when heated in air than in aqueous solution. Yellowing by heating in buffer solutions increases with pH value and is also markedly affected by the nature of the buffer ions, glycine and related nitrogen compounds causing least yellowing and pyrophosphate most when

F. G. Lennox

1960-01-01

377

Yellow Sea Acoustic Uncertainty Caused by Hydrographic Data Error  

E-print Network

Yellow Sea Acoustic Uncertainty Caused by Hydrographic Data Error Peter C. Chu, Carlos J. Cintron is presented by Prof. Kevin Smith at NPS #12;Yellow Sea Bottom Sediment Chart · Four Bottom Sediment types 1. Mud 2. Sand 3. Gravel 4. Rock #12;Yellow Sea Bottom Topography · Water depth in most of the region

Chu, Peter C.

378

YELLOW SEA ACOUSTIC UNCERTAINTY CAUSED BY HYDROGRAPHIC DATA ERROR  

E-print Network

YELLOW SEA ACOUSTIC UNCERTAINTY CAUSED BY HYDROGRAPHIC DATA ERROR PETER C. CHU AND CARLOS J) Modular Ocean Data Assimilation System (MODAS) model in shallow water (such as the Yellow Sea) mine errors) on the acoustic uncertainty in the Yellow Sea is investigated using CASS/GRAB. 2 Environment

Chu, Peter C.

379

Wind-driven effects on the Yellow Sea Warm Current  

Microsoft Academic Search

The Yellow Sea is a shallow basin with an average depth of 44 m located between China_and the Korean Peninsula. One of the dominant ocean circulation features of the Yellow Sea is a warm water intrusion known as the Yellow Sea Warm Current. This feature is present throughout the year but reaches its farthest northward extension in winter. The circulation

Andrea C. Mask; James J. O'Brien; Ruth Preller

1998-01-01

380

A unique Yellow River-derived distal subaqueous delta in the Yellow Sea  

Microsoft Academic Search

Newly acquired high-resolution Chirp sonar profiles reveal a unique Yellow River-derived, alongshore distributed, bidirectional (landward and seaward) across-shelf transported, omega-shaped (“?”) distal subaqueous deltaic lobe deposited around the eastern tip of the Shandong Peninsula in the Yellow Sea. This clinoform deposit directly overlies the postglacial transgressive surface, featured by convex-up seafloor morphology, up to 40 m thick locally. Radiocarbon-14 dates from

Z. S. Yang; J. P. Liu

2007-01-01

381

Holocene development of the Yellow River's subaqueous delta, North Yellow Sea  

Microsoft Academic Search

High-resolution seismic profiles from the North Yellow Sea reveal a 20–40-m-thick subaqueous clinoform delta that wraps around the eastern end of the Shandong Peninsula, extending into the South Yellow Sea. This complex sigmoidal-oblique clinoform, containing an estimated 400 km3 of sediment, overlies prominent relict transgressive surfaces. The nearshore topset of the clinoform, <30-m water depth, has a ?1:1000 gradient, with

J. Paul Liu; John D. Milliman; Shu Gao; Peng Cheng

2004-01-01

382

Portal vein arterialization technique for liver transplantation patients  

PubMed Central

Liver transplantations were performed on two patients with hepatic failure caused by liver cirrhosis. Hard obsolete thrombi and portal venous sclerosis were observed in the major portal veins of both patients. The arteria colica media of one recipient and the portal vein of the donor were anastomosed end-to-end. The hepatic artery of the first donor was anastomosed end-to end with the gastroduodenal artery of the first recipient; meanwhile, the portal vein of the second donor was simultaneously anastomosed end- to-end with the common hepatic artery of the second recipient. The blood flow of the portal vein, the perfusion of the donor liver and liver function were satisfactory after surgery. Portal vein arterialization might be an effective treatment for patients whose portal vein reconstruction was difficult.

Zhang, Kun; Jiang, Yi; Lv, Li-Zhi; Cai, Qiu-Cheng; Yang, Fang; Hu, Huan-Zhang; Zhang, Xiao-Jin

2014-01-01

383

Loop-mediated isothermal amplification for rapid detection of the causal agents of cassava brown streak disease.  

PubMed

The causal agents of cassava brown streak disease have recently been identified as Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Primers have been developed for rapid detection of these viruses by reverse transcription loop-mediated isothermal amplification (RT-LAMP). Performance of the RT-LAMP assays compared favourably with published RT-PCR and real-time RT-PCR methods. Furthermore, amplification by RT-LAMP is completed in 40 min and does not require thermal cycling equipment. Modification of the RT-LAMP reactions to use labelled primers allowed rapid detection of amplification products using lateral flow devices containing antibodies specific to the incorporated labels, avoiding the need for fluorescence detection or gel electrophoresis. PMID:22820076

Tomlinson, J A; Ostoja-Starzewska, S; Adams, I P; Miano, D W; Abidrabo, P; Kinyua, Z; Alicai, T; Dickinson, M J; Peters, D; Boonham, N; Smith, J

2013-08-01

384

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

SciTech Connect

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.

Li Zhengyan; Zgadzaj, Rafal; Wang Xiaoming; Reed, Stephen; Dong Peng; Downer, Michael C. [Department of Physics, University of Texas at Austin, Austin, TX, 78712 (United States)

2010-11-04

385

Deep vein thrombosis chemoprophylaxis in plastic surgery.  

PubMed

The practice of plastic surgery is a unique mixture of art and science, and both must be carefully balanced to provide the best possible care for patients. To do that, clinicians should be practicing evidence-based medicine. This article discusses the prevalence and risks associated with deep vein thrombosis and the reasons and options for its possible chemoprophylaxis. Until evidence-based medicine best-practice recommendations can be developed, it would be prudent for clinicians to empirically select and consistently apply a risk stratification system and prophylaxis regimen of their choice for the benefit of their patients. PMID:23830748

Gold, Alan

2013-07-01

386

Prognostic Evaluation Based on Cortical Vein Score Difference in Stroke  

PubMed Central

Background and Purpose Multimodal imaging in acute ischemic stroke defines the extent of arterial collaterals, resultant penumbra, and associated infarct core, yet limitations abound. We identified superficial and deep venous drainage patterns that predict outcomes in patients with a proximal arterial occlusion of the anterior circulation. Methods An observational study that used computed tomography (CT) angiography to detail venous drainage in a consecutive series of patients with a proximal anterior circulation arterial occlusion. The principal veins that drain the cortex (superficial middle cerebral, vein of Trolard, vein of Labbé, and basal vein of Rosenthal) and deep structures were scored with a categorical scale on the basis of degree of contrast enhancement. The Prognostic Evaluation based on Cortical vein score difference In Stroke score encompassing the interhemispheric difference of the composite scores of the veins draining the cortices (superficial middle cerebral+vein of Trolard+vein of Labbé+basal vein of Rosenthal) was analyzed with respect to 90-day modified Rankin Scale outcomes. Results Thirty-nine patients were included in the study. A Prognostic Evaluation based on Cortical vein score difference In Stroke score of 4 to 8 accurately predicted poor outcomes (modified Rankin Scale, 3–6; odds ratio, 20.53; P<0.001). On stepwise logistic regression analyses adjusted for CT Alberta stroke program early CT score, CT angiography collateral grading and National Institutes of Health Stroke Scale score, a Prognostic Evaluation based on Cortical vein score difference In Stroke score of 4 to 8 (odds ratio, 23.598; P=0.009) and an elevated admission National Institutes of Health Stroke Scale (odds ratio, 1.423; P=0.023) were independent predictors of poor outcome. Conclusions The Prognostic Evaluation based on Cortical vein score difference In Stroke score, a novel measure of venous enhancement on CT angiography, accurately predicts clinical outcomes. Venous features on computed tomography angiography provide additional characterization of collateral perfusion and prognostication in acute ischemic stroke. PMID:23887836

Parthasarathy, Rajsrinivas; Kate, Mahesh; Rempel, Jeremy L.; Liebeskind, David S.; Jeerakathil, Thomas; Butcher, Kenneth S.; Shuaib, Ashfaq

2014-01-01

387

Kinematics of crystal growth in syntectonic fibrous veins  

Microsoft Academic Search

Abstract--Detaded observations of a set of fibrous antitaxial calcite veins in a slate reveal that some,of the calcite fibres do not connect material markers,on both sides of the vein and can therefore not have tracked the full opening trajectory dunng,vein growth. Thts calls for a better understanding,of the mechanisms,of fibre formation and reliable criteria to test the tracking hypothesis. Based

J. L. Urai; P. F. Williams; H VANROERMUND

1991-01-01

388

Towards measurement of outcome for patients with varicose veins  

Microsoft Academic Search

OBJECTIVE--To develop a valid and reliable outcome measure for patients with varicose veins. DESIGN--Postal questionnaire survey of patients with varicose veins. SETTING--Surgical outpatient departments and training general practices in Grampian region. SUBJECTS--373 patients, 287 of whom had just been referred to hospital for their varicose veins and 86 who had just consulted a general practitioner for this condition and, for

A M Garratt; L M Macdonald; D A Ruta; I T Russell; J K Buckingham; Z H Krukowski

1993-01-01

389

Auxin Is Required for Leaf Vein Pattern in Arabidopsis  

Microsoft Academic Search

To investigate possible roles of polar auxin transport in vein patterning, cotyledon and leaf vein patterns were compared for plants grown in medium containing polar auxin transport inhibitors (N-1-naphthylphthalamic acid, 9-hydroxyfluorene-9-carboxylic acid, and 2,3,5-triiodobenzoic acid) and in medium containing a less well-characterized inhibitor of auxin-mediated processes, 2-(p- chlorophynoxy)-2-methylpropionic acid. Cotyledon vein pattern was not affected by any inhibitor treatments, although

Leslie E. Sieburth

1999-01-01

390

An idiopathic azygos vein aneurysm mimicking a mediastinal mass.  

PubMed

Azygos vein aneurysms are very rare causes of mediastinal masses and are usually accidental findings on chest roentgenography. Most are detected in patients with portal hypertension or venous malformations. An idiopathic azygos vein aneurysm is assumed to be congenital and is much more exceptional. We present the case of a 76-year-old man who underwent excision of an idiopathic azygos vein aneurysm by video-assisted thoracoscopic surgery (VATS). PMID:24996721

Ichiki, Yoshinobu; Hamatsu, Takayuki; Suehiro, Taketoshi; Koike, Makiko; Tanaka, Fumihiro; Sugimachi, Keizo

2014-07-01

391

Pulsed Doppler duplex sonography and CT of portal vein thrombosis  

SciTech Connect

Five patients with partial or complete portal vein thrombosis were examined by both computed tomography (CT) and pulsed Doppler duplex scanning. Duplex scanning correctly identified portal vein thrombosis in all five. Duplex sonography may be the preferred technique to detect and follow portal vein thrombosis because of lower cost, lack of need for intravenous contrast material, and easier availability for multiple follow-up examinations.

Miller, V.E.; Berland, L.L.

1985-07-01

392

Formation of retinochoroidal collaterals in central retinal vein occlusion  

Microsoft Academic Search

Purpose: To demonstrate the drainage routes that compensate the venous congestion in central retinal vein occlusion.Methods: Indocyanine green angiography was performed in 13 eyes of 13 patients with central retinal vein occlusion at the involutional stage using a scanning laser ophthalmoscope. The interval between onset of central retinal vein occlusion and indocyanine green angiography ranged from 1.0 to 9.3 years

Kyoichi Takahashi; Kanemitsu Muraoka; Shoji Kishi; Koichi Shimizu

1998-01-01

393

Computed tomography findings in pseudothrombosis of the iliofemoral vein.  

PubMed

Computed tomography findings in 3 patients with apparent thrombosis of an iliofemoral vein due to mixing artifact related to venous collateral formation are presented, 1 with portosystemic collaterals and 2 with collaterals secondary to subclavian vein thrombosis. Mixing artifact or asymmetric enhancement related to collateral formation should be considered for an apparent thrombus in the iliofemoral vein. Examination of axial and reformatted images may facilitate recognition and help avoid an erroneous diagnosis of deep venous thrombosis. PMID:20118738

Desai, Gaurav; Poder, Liina; Wang, Zhen J; Yeh, Benjamin M; Webb, Emily M; Coakley, Fergus V

2010-01-01

394

[Video endoscopy-assisted saphenous vein occlusion--minimal invasive concept for treatment of varicose veins].  

PubMed

Videoendoscopy-assisted saphena occlusion (VASO) is an minimally invasive technique for the treatment of varicosis with crossectomy, dissection of perforating veins and occlusion of the saphena by endoscopic control. The advantages are lower level of pain, remobilisation without problems, and fewer complications of wound healing. Early results correspond to stripping. PMID:9102018

Klose, G; Weber, B

1996-01-01

395

Advantages of using volar vein repair in finger replantations.  

PubMed

Providing adequate venous outflow is essential in finger replantation surgeries. For a successful result, the quality and quantity of venous repairs should be adequate to drain arterial inflow. The digital dorsal venous plexus is a reliable source of material for venous repairs. Classically, volar digital veins have been used only when no other alternative was available. However, repairing volar veins to augment venous outflow has a number of technical advantages and gives a greater chance of survival. Increasing the repaired vein:artery ratio also increases the success of replantation. The volar skin, covering the volar vein, is less likely to be avulsed during injury and is also less likely to turn necrotic, than dorsal skin, after the replantation surgery. Primary repair of dorsal veins can be difficult due to tightness ensuing from arthrodesis of the underlying joint in flexion. In multiple finger replantations, repairing the volar veins after arterial repair and continuing to do so for each finger in the same way without changing the position of the hand and surgeon save time. In amputations with tissue loss, the size discrepancy is less for volar veins than for dorsal veins. We present the results of 366 finger replantations after volar vein repairs. PMID:23982066

Mersa, Berkan; Kabakas, Fatih; Pürisa, Hüsrev; Özçelik, Ismail Bülent; Ye?ilo?lu, Nebil; Sezer, Ilker; Tunçer, Serdar

2014-01-01

396

Finger-Vein Verification Based on Multi-Features Fusion  

PubMed Central

This paper presents a new scheme to improve the performance of finger-vein identification systems. Firstly, a vein pattern extraction method to extract the finger-vein shape and orientation features is proposed. Secondly, to accommodate the potential local and global variations at the same time, a region-based matching scheme is investigated by employing the Scale Invariant Feature Transform (SIFT) matching method. Finally, the finger-vein shape, orientation and SIFT features are combined to further enhance the performance. The experimental results on databases of 426 and 170 fingers demonstrate the consistent superiority of the proposed approach. PMID:24196433

Qin, Huafeng; Qin, Lan; Xue, Lian; He, Xiping; Yu, Chengbo; Liang, Xinyuan

2013-01-01

397

Wind Streaks  

NASA Technical Reports Server (NTRS)

[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.

2004-01-01

398

Imported yellow fever in a United States citizen.  

PubMed

The last imported case of yellow fever seen in this country was in 1924. We report a case of yellow fever acquired by an American tourist who visited the jungles of Brazil along the Rio Negro and Amazon Rivers. The patient died 6 days after hospital admission and 10 days after his first symptoms appeared. Yellow fever virus was recovered from clinical specimens, and the isolate was genetically similar to the E genotype IIB of South American yellow fever viruses. This patient's illness represents a case of vaccine-preventable death since he failed to be immunized with a recommended preexposure yellow fever vaccine. PMID:9402373

McFarland, J M; Baddour, L M; Nelson, J E; Elkins, S K; Craven, R B; Cropp, B C; Chang, G J; Grindstaff, A D; Craig, A S; Smith, R J

1997-11-01

399

Slit-mounted LED fiducial system for rotating mirror streak cameras  

SciTech Connect

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.

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

1991-01-01

400

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

NASA Astrophysics Data System (ADS)

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.

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

2012-09-01

401

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

NASA Astrophysics Data System (ADS)

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 103) 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.

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

2014-08-01

402

Gas-phase lifetimes of nucleobase analogues by picosecond pumpionization and streak techniques.  

PubMed

The picosecond (ps) timescale is relevant for the investigation of many molecular dynamical processes such as fluorescence, nonradiative relaxation, intramolecular vibrational relaxation, molecular rotation and intermolecular energy transfer, to name a few. While investigations of ultrafast (femtosecond) processes of biological molecules, e.g. nucleobases and their analogues in the gas phase are available, there are few investigations on the ps time scale. We have constructed a ps pump-ionization setup and a ps streak camera fluorescence apparatus for the determination of lifetimes of supersonic jet-cooled and isolated molecules and clusters. The ps pump-ionization setup was used to determine the lifetimes of the nucleobase analogue 2-aminopurine (2AP) and of two 2AP?(H2O)n water cluster isomers with n=1 and 2. Their lifetimes lie between 150 ps and 3 ns and are strongly cluster-size dependent. The ps streak camera setup was used to determine accurate fluorescence lifetimes of the uracil analogue 2-pyridone (2PY), its self-dimer (2PY)2, two isomers of its trimer (2PY)3 and its tetramer (2PY)4, which lie in the 7-12 ns range. PMID:24983611

Blaser, Susan; Frey, Hans-Martin; Heid, Cornelia G; Leutwyler, Samuel

2014-01-01

403

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

SciTech Connect

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.

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

1994-09-01

404

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

SciTech Connect

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.

Droemer, Darryl W. [National Security Technologies, LLC; Crain, Marlon D.; Lare, Gregory A. [National Security Technologies, LLC; Bennett, Nichelle L. [National Security Technologies, LLC; Johnston, Mark D. [Sandia National Laboratories

2013-06-13

405

Can deep vein thrombosis be predicted after varicose vein operation in women in rural areas?  

PubMed

Introduction. Chronic venous disease is a group of symptoms caused by functional and structural defects of the venous vessels. One of the most common aspects of this disease is the occurrence of varicose veins. There are many ways of prevention and treatment of varicose veins, but in Poland the leading one is still surgery. As in every medical procedure there is the possibility of some complications. One of them is deep vein thrombosis (DVT). The diagnosis of DVT can be difficult, especially when access to a specialist is limited, such as in case of rural patients. The aim of the study. The aim of the study was estimation of the influence of LMWH primary prophylaxis on the formation of postoperative DVT, as well as sensitivity and specificity of clinical examination and D-dimer value in diagnosis of postoperative DVT in women. Materials and methods. The study was conducted in a group of 93 women operated on in the Department of General, Vascular Surgery and Angiology at the Karol Marcinkowski University of Medical Sciences in Pozna?, Poland. The patients had undergone a varicose vein operation and were randomly divided into two groups: A - 48 women receiving LMWH during two days of the perioperative period, B - 45 women receiving LMWH during seven days of the perioperative period. Results. There was no significant difference in the postoperative DVT complications in both groups. The value of D-dimer > 0.987 mcg/ml and swelling > 1.5 cm of shin (in comparison to the preoperative period) plays a significant role in diagnosis of DVT. Conclusions. The extended primary prophylaxis with LMWH does not affect the amount or quality of thrombotic complications after varicose vein operation. If the DVT occurs, the evaluation of the D - dimer and careful clinical examination can be a useful method for its diagnosis. PMID:25292137

Warot, Marcin; Synowiec, Tomasz; Wencel-Warot, Agnieszka; Daroszewski, Przemys?aw; Bojar, Iwona; Micker, Maciej; Ch?ci?ski, Pawe?

2014-09-01

406

Percutaneous transhepatic portal vein stenting in a patient with benign non-transplant postoperative portal vein stenosis: A case report  

PubMed Central

Extrahepatic portal vein stenosis is caused by a variety of benign and malignant diseases and results in development of symptoms due to portal hypertension. Benign post-surgical adhesions causing portal vein stenosis in non-transplant population is an uncommon etiology of portal hypertension. Endovascular treatment of such patients with angioplasty and stenting is uncommonly reported in literature. We report a case of portal hypertension caused by benign postoperative portal vein fibrosis, successfully treated by self-expandable metallic stent. PMID:24604941

Madhusudhan, KS; Agrawal, Nikhil; Srivastava, Deep N; Pal, Sujoy; Gupta, Arun K

2013-01-01

407

Suitability of Varicose Veins for Endovenous Treatments  

SciTech Connect

The aim of the study was to assess the suitability of radiofrequency ablation (RFA), endovenous laser ablation (EVLA), and foam sclerotherapy (FS) for patients with symptomatic varicose veins (VVs). The study comprised 403 consecutive patients with symptomatic VVs. Data on 577 legs from 403 consecutive patients with symptomatic VVs were collected for the year 2006. Median patient age was 55 years (interquartile range 45-66), and 62% patients were women. A set of criteria based on duplex ultrasonography was used to select patients for each procedure. Great saphenous vein (GSV) reflux was present in 77% (446 of 577) of legs. Overall, 328 (73%) of the legs were suitable for at least one of the endovenous options. Of the 114 legs with recurrent GSV reflux disease, 83 (73%) were suitable to receive endovenous therapy. Patients with increasing age were less likely to be suitable for endovenous therapy (P = 0.03). Seventy-three percent of patients with VVs caused by GSV incompetence are suitable for endovenous therapy.

Goode, S. D., E-mail: s.goode@sheffield.ac.u [Sheffield Teaching Hospitals, Department of Radiology (United Kingdom); Kuhan, G.; Altaf, N.; Simpson, R.; Beech, A.; Richards, T.; MacSweeney, S. T.; Braithwaite, B. D. [Queens Medical Centre, Department of Vascular and Endovascular Surgery (United Kingdom)

2009-09-15

408

High-efficiency 20 W yellow VECSEL.  

PubMed

A high-efficiency optically pumped vertical-external-cavity surface-emitting laser emitting 20 W at a wavelength around 588 nm is demonstrated. The semiconductor gain chip emitted at a fundamental wavelength around 1170-1180 nm and the laser employed a V-shaped cavity. The yellow spectral range was achieved by intra-cavity frequency doubling using a LBO crystal. The laser could be tuned over a bandwidth of ~26 nm while exhibiting watt-level output powers. The maximum conversion efficiency from absorbed pump power to yellow output was 28% for continuous wave operation. The VECSEL's output could be modulated to generate optical pulses with duration down to 570 ns by directly modulating the pump laser. The high-power pulse operation is a key feature for astrophysics and medical applications while at the same time enables higher slope efficiency than continuous wave operation owing to decreased heating. PMID:24663985

Kantola, Emmi; Leinonen, Tomi; Ranta, Sanna; Tavast, Miki; Guina, Mircea

2014-03-24

409

Marylanders defeat Philadelphia: yellow fever updated.  

PubMed Central

Those strategic points which influence this amateur historian to declare a victory for Baltimore and Maryland over Philadelphia are: I. Based upon clinical and epidemiological data, two Marylanders, Potter and Davidge, were among the first to contest Rush and his contagion theory; they told him so and published their views. To prove this point, Potter went to the extreme of inoculating himself with presumedly infected material. Stubbins Ffirth, a young University of Pennsylvania medical student, did the same four years later. To Rush's credit was ultimate abandonment of his originally held views. II. John Crawford, of Baltimore, although not the originator of the insect concept of transmission of infectious agents, published his concepts in 1811. III. Henry Rose Carter, a Maryland graduate, clearly delineated, in 1898, that after identification of an index case of yellow fever an extrinsic incubation period was necessary before the evolution of secondary cases. IV. James Carroll, another University of Maryland graduate, who worked as Deputy under Walter Reed with Lazear and Agramonte, helped prove Finlay's original concept that the Aedes aegypti mosquito was the natural vector of yellow fever. Carroll himself was the first experimentally induced case. V. Studies in primates provide new approaches for management of yellow fever. Nutritional support and treatment with specific anti-viral agents may be useful for therapy of human yellow fever. Maryland members of the Climatological are mindful of Philadelphia's rich medical heritage and of the many battles won in the City of Brotherly Love. Physicians in colonial and early America experienced The best and worst of times, theirs was an age of foolishness and belief, of incredulity and light, of darkness, despair and hope. This tale of two cities ends in peace. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 10 Fig. 11 PMID:822563

Woodward, T. E.; Beisel, W. R.; Faulkner, R. D.

1976-01-01

410

Comparison of black, purple, and yellow barleys  

Microsoft Academic Search

Many barley landraces are purple-or black-seeded, but the chemical composition of these purple-and black- seeded barley is rarely examined. Therefore, studies were conducted to determine if the chemical composition of purple and black barleys differs from that of yellow barleys. Four sets of genetic materials were used for these studies: 96 doubled-haploid (DH) lines, 10 near-isogenic lines, 40 landraces, and

Thin Meiw Choo; Bernard Vigier; Keh Ming Ho; Salvatore Ceccarelli; Stefania Grando; Jerome D. Franckowiak

2005-01-01

411

Preventing intimal thickening of vein grafts in vein artery bypass using STAT-3 siRNA  

PubMed Central

Background Proliferation and migration of vascular smooth muscle cells (VSMCs) play a key role in neointimal formation which leads to restenosis of vein graft in venous bypass. STAT-3 is a transcription factor associated with cell proliferation. We hypothesized that silencing of STAT-3 by siRNA will inhibit proliferation of VSMCs and attenuate intimal thickening. Methods Rat VSMCs were isolated and cultured in vitro by applying tissue piece inoculation methods. VSMCs were transfected with STAT 3 siRNA using lipofectamine 2000. In vitro proliferation of VSMC was quantified by the MTT assay, while in vivo assessment was performed in a venous transplantation model. In vivo delivery of STAT-3 siRNA plasmid or scramble plasmid was performed by admixing with liposomes 2000 and transfected into the vein graft by bioprotein gel applied onto the adventitia. Rat jugular vein-carotid artery bypass was performed. On day 3 and7 after grafting, the vein grafts were extracted, and analyzed morphologically by haematoxylin eosin (H&E), and assessed by immunohistochemistry for expression of Ki-67 and proliferating cell nuclear antigen (PCNA). Western-blot and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect the protein and mRNA expression in vivo and in vitro. Cell apoptosis in vein grafts was detected by TUNEL assay. Results MTT assay shows that the proliferation of VSMCs in the STAT-3 siRNA treated group was inhibited. On day 7 after operation, a reduced number of Ki-67 and PCNA positive cells were observed in the neointima of the vein graft in the STAT-3 siRNA treated group as compared to the scramble control. The PCNA index in the control group (31.3 ± 4.7) was higher than that in the STAT-3 siRNA treated group (23.3 ± 2.8) (P < 0.05) on 7d. The neointima in the experimental group(0.45 ± 0.04 ?m) was thinner than that in the control group(0.86 ± 0.05 ?m) (P < 0.05).Compared with the control group, the protein and mRNA levels in the experimental group in vivo and in vitro decreased significantly. Down regulation of STAT-3 with siRNA resulted in a reduced expression of Bcl-2 and cyclin D1. However, apoptotic cells were not obviously found in all grafts on day 3 and 7 post surgery. Conclusions The STAT-3 siRNA can inhibit the proliferation of VSMCs in vivo and in vitro and attenuate neointimal formation. PMID:22216901

2012-01-01

412

Early results of a prospective randomized trial of spliced vein versus polytetrafluoroethylene graft with a distal vein cuff for limb-threatening ischemia  

Microsoft Academic Search

Objective: Single-piece vein remains the conduit of choice in patients who need bypass grafting for limb salvage. When this option is not available, two of the remaining options are prosthetic bypass graft or several segments of vein spliced together. In this study, we compare spliced vein bypass grafting versus polytetrafluoroethylene grafting with a distal vein cuff in patients with limb-threatening

Paul B. Kreienberg; R. Clement Darling; Benjamin B. Chang; Bradley J. Champagne; Philip S. K. Paty; Sean P. Roddy; William E. Lloyd; Kathleen J. Ozsvath; Dhiraj M. Shah

2002-01-01

413

Pulmonary Vein Stenosis After Catheter Ablation of Atrial Fibrillation  

Microsoft Academic Search

Background—This report describes the complication of pulmonary vein stenosis with resultant severe pulmonary hypertension that developed in 2 patients after successful catheter ablation of chronic atrial fibrillation. Methods and Results—Three months after successful catheter ablation of atrial fibrillation, both patients developed progressive dyspnea and pulmonary hypertension. Both were found to have severe stenosis of all 4 pulmonary veins near the

Ivan M. Robbins; Edward V. Colvin; Thomas P. Doyle; W. Evans Kemp; James E. Loyd; William S. McMahon; G. Neal Kay

414

Calcite veins in northeastern Puente Hills, southern California  

Microsoft Academic Search

Calcite vein fillings are locally exposed in the northeastern Puente Hills, 2 mi southwest of Pomona on the northeast margin of the Los Angeles basin. They occur within northeast- and northwest-trending faults in the middle Miocene Glendora Volcanics and in the Soquel Member of the upper Miocene Puente Formation. The veins range in width from 1 in. to 15 ft,

M. O. Spira; D. H. Zenger

1986-01-01

415

Splenic Vein Thrombosis and Gastrointestinal Bleeding in Chronic Pancreatitis  

Microsoft Academic Search

The most common cause of isolated thrombosis of the splenic vein is chronic pancreatitis caused by perivenous inflammation. Although splenic vein thrombosis (SVT) has been reported in up to 45% of patients with chronic pancreatitis, most patients with SVT remain asymptomatic. In those patients with gastrointestinal bleeding secondary to esophageal or gastric varices, the diagnostic test of choice to assess

Sharon M. Weber; Layton F. Rikkers

2003-01-01

416

[Crossectomy in ascending superficial thrombophlebitis of the leg veins].  

PubMed

Ascending thrombophlebitis of the superficial leg veins is known to propagate into the deep leg veins and to embolize. In a prospective study we followed up 44 patients with sonographically diagnosed ascending thrombophlebitis into the deep veins (V. saphena magna n = 40, V. saphena parva n = 4). In 15 of 44 cases (34%) thrombosis of the crossing veins was found intraoperatively and 6 of 44 crossings were filled with floating thrombi into the deep vein lumina (14%). Among complications of treatment (11.4%) recurrence of thrombi in the ligated superficial residual vein stump was seen in 2 of 44 cases. One of these patients suffered a symptomatic, non-fulminant pulmonary embolism. The other patient developed a femoral vein thrombosis. 1 patient had an abscess and 1 a seroma of the groin. In 11% of all cases ascending thrombophlebitis diagnosed duplex sonographically was not effective in preventing propagation of thrombi into the deep veins thromboembolism remains a complication of ascending thrombophlebitis. PMID:9454490

Kock, H J; Krause, U; Albrecht, K H; van der Laan, E; Rudofsky, G; Eigler, F W

1997-01-01

417

Tissue Fibrinolytic Activity in Different Types of Varicose Veins  

Microsoft Academic Search

The fibrinolytic activity of the venous wall was investigated by using Todd's technique 1 in 92 patients with different types of varicosis.A control group consisted of 19 patients with apparently normal superficial veins who had had a saphenectomy prior to an aortocoronary bypass operation. Fibrinolytic activity was mainly localized in the adventitia of varicose and nor mal veins. It significantly

Viola Hach; Monika Fink; Norbert Blees; Inge Scharrer

1986-01-01

418

Hand Vein Biometry Based on Geometry and Appearance Methods  

E-print Network

1 Hand Vein Biometry Based on Geometry and Appearance Methods Aycan Yuksel*, Lale Akarun. These patterns in the hands are assumed to be unique to each individual and they do not change over time except features for personal identification. In this study, we present a novel hand vein database and a biometric

419

Green Veining: Landscape Determinants of Biodiversity in European Agricultural Landscapes  

Microsoft Academic Search

Many semi-natural landscape elements, the so-called green veining, are disappearing from the intensively used agricultural landscapes of Europe. In order to develop or restore biodiversity in these networks, it is necessary to quantify the relation between biodiversity and amount, spatial arrangement and management intensity of green veining elements. In this review, we investigate whether biodiversity increases with the amount of

Carla J. Grashof-Bokdam; Frank van Langevelde

2005-01-01

420

Exercise-Induced Deep Vein Thrombosis of the Upper Extremity  

Microsoft Academic Search

Paget-Schroetter syndrome or effort-related upper extremity deep vein thrombosis is a rare condition that usually afflicts young healthy individuals, most commonly males. The cause is multifactorial but almost always involves extrinsic compression of the subclavian vein at the thoracic inlet, causing venous stenosis from repetitive trauma. The diagnosis of this condition may be difficult, and its delay may contribute to

Leonardo R. Brandão; Suzan Williams; Walter H. A. Kahr; Clodagh Ryan; Michael Temple; Anthony K.C. Chan

2006-01-01

421

Cellular repopulation of human vein allograft bypass grafts  

Microsoft Academic Search

Purpose: Vein allografts are an alternative conduit for patients lacking available autogenous vein. The ability to develop a neoendothelium is a potential advantage of allografts over other nonautogenous grafts, because endothelial cells have been shown to play numerous essential roles in vessel survival. However, repopulation by endothelial cells has not previously been demonstrated or characterized in human subjects. Methods: In

Todd R Johnson; John E Tomaszewski; Jeffrey P Carpenter

2000-01-01

422

Gender does not impact infrainguinal vein bypass graft outcome  

Microsoft Academic Search

Background: The percentage of women requiring infrainguinal bypass graft operations continues to increase, whereas the effect of gender on postoperative outcome remains unclear. The purpose of this study was to assess the influence of gender on patient selection and outcome in patients requiring infrainguinal vein bypass grafting procedures. Methods: This retrospective study reviewed 217 infrainguinal vein bypass grafts performed over

Spiros G Frangos; Suzanne Karimi; Morris D Kerstein; Mona Harpavat; Bauer Sumpio; Andrew B Roberts; Vivian Gahtan

2000-01-01

423

Relation between retinal vein occlusions and axial length  

Microsoft Academic Search

AIMS: To evaluate the ocular axial length as a risk factor for development of central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO). METHODS: Ocular axial lengths were measured, by A-scan ultrasonography, in 17 patients with CRVO and 41 patients with BRVO and compared with those of contralateral unaffected eyes and 66 age matched controls. RESULTS: In 17

N. Aritürk; Y. Oge; D. Erkan; Y. Süllü; F. Mohajerý

1996-01-01

424

Pseudoexfoliation and glaucoma in eyes with retinal vein occlusion  

Microsoft Academic Search

Purpose: To evaluate pseudoexfoliation (PE) and pre-existent glaucoma in eyes with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). Methods: Consecutive eyes with a diagnosis of BRVO (73 eyes of 70 patients) and CRVO (53 eyes of 49 patients) examined between July and December 1998 comprised the study eyes. Age-matched control group consisted of 384 eyes of

Osman A. Saatci; Sevgi Tongal Ferliel; Murat Ferliel; Süleyman Kaynak; Mehmet H. Ergin

1999-01-01

425

Plasma Homocysteine and Cysteine Levels in Retinal Vein Occlusion  

Microsoft Academic Search

PURPOSE. To determine plasma homocysteine and cysteine lev- els in patients with retinal vein occlusion (RVO) and in healthy subjects and to ascertain whether there are statistically signif- icant differences between patients and control subjects. METHODS. In this case- control study, the study group consisted of 75 consecutive patients with RVO: 33 had central retinal vein occlusion (CRVO), and 42

Antonio Pinna; Ciriaco Carru; Angelo Zinellu; Stefano Dore; Luca Deiana; Francesco Carta

2006-01-01

426

Cardiovascular and thrombophilic risk factors for central retinal vein occlusion  

Microsoft Academic Search

Retinal vein occlusion (RVO) is a relatively common disease that is often associated with a variety of systemic disorders including arterial hypertension, diabetes mellitus, dyslipidemia, and systemic vasculitis. There are various types of RVO, categorized on the basis of the site of occlusion and on the type of consequent vascular damage. Central retinal vein occlusion (CRVO) is the most frequently

Domenico Prisco; Rossella Marcucci; Laura Bertini; Anna Maria Gori

2002-01-01

427

Composition of arsenopyrite from topaz greisen veins in southeastern Missouri  

Microsoft Academic Search

Arsenopyrite occurs in greisen-sulfide veins hosted by unmetamorphosed Precambrian granite and rhyolite in the Silver Mine district of southeastern Missouri, Greisenization and sulfide mineralization appear to have been a continuous depositional sequence which recorded falling temperature in a near-surface vein environment. Textural criteria imply that equilibrium existed between arsenopyrite and pyrite and that this pair crystallized in an intermediate paragenetic

G. R. Lowell; C. Gasparrini

1982-01-01

428

Endoscopic versus traditional saphenous vein harvesting: a prospective, randomized trial  

Microsoft Academic Search

Background. Saphenous vein harvested with a traditional longitudinal technique often results in leg wound complications. An alternative endoscopic harvest technique may decrease these complications.Methods. One hundred twelve patients scheduled for elective coronary artery bypass grafting were prospectively randomized to have vein harvested using either an endoscopic (group A, n = 54) or traditional technique (group B, n = 58). Groups

Keith B Allen; Gary L Griffith; David A Heimansohn; Robert J Robison; Robert G Matheny; John J Schier; Edward B Fitzgerald; Carl J Shaar

1998-01-01

429

Applications of a streak-camera-based imager with simultaneous high space and time resolution  

NASA Astrophysics Data System (ADS)

A high-speed imaging device has been built that is capable of recording several hundred images over a time span of 25 to 400 ns. The imager is based on a streak camera, which provides both spatial and temporal resolution. The system's current angular resolution is 16 X 16 pixels, with a time resolution of 250 ps. It was initially employed to provide 3-D images of objects, in conjunction with a short-pulse (approximately 100 ps) laser. For the 3-D (angle-angle-range) laser radar, the 250 ps time resolution corresponds to a range resolution of 4 cm. In the 3-D system, light from a short-pulse laser (a frequency-doubled, Q-switched, mode-locked Nd:YAG laser operating at a wavelength of 532 nm) flood-illuminates a target of linear dimension approximately 1 m. The returning light from the target is imaged, and the image is dissected by a 16 X 16 array of optical fibers. At the other end of the fiber optic image converter, the 256 fibers form a vertical line array, which is input to the slit of a streak camera. The streak camera sweeps the input line across the output phosphor screen so that horizontal position is directly proportional to time. The resulting 2-D image (fiber location vs. time) at the phosphor is read by an intensified (SIT) vidicon TV tube, and the image is digitized and stored. A computer subsequently decodes the image, unscrambling the linear pixels into an angle-angle image at each time or range bin. We are left with a series of snapshots, each one depicting the portion of target surface in a given range bin. The pictures can be combined to form a 3-D realization of the target. Continuous recording of many images over a short time span is of use in imaging other transient phenomena. These applications share a need for multiple images from a nonrepeatable transient event of time duration on the order of nanoseconds. Applications discussed for the imager include (1) pulsed laser beam diagnostics -- measuring laser beam spatial and temporal structure, (2) reflectivity monitoring during pulsed laser annealing of microelectronics, and (3) detonics or shock wave research, especially microscopic studies of shocks produced by laser pulses.

Klick, David I.; Knight, Frederick K.

1993-01-01

430

Deep Vein Thrombosis: Symptoms, Diagnosis, Treatment and Latest NIH Research | NIH MedlinePlus the Magazine  

MedlinePLUS

... Feature: Deep Vein Thrombosis Deep Vein Thrombosis: Symptoms, Diagnosis, Treatment and Latest NIH Research Past Issues / Spring ... pain Red or discolored skin on the leg Diagnosis Your doctor will diagnose deep vein thrombosis (DVT) ...

431

Resolution limitations and optimization of the ITT F4157 streak tube focus for fast (10 ps) operation  

SciTech Connect

The ITT F4157 image tube is biased at voltages far from the original design for operation in an ultrafast (10 ps) streak camera. Its output resolution at streak camera operating potentials has been measured as a function of input slit width, incident-light wavelength, and focus-grid voltage. The results are similar to those reported for the RCA C73435 streak tube. Indeed, the two tubes can be substituted for each other with minor mechanical modifications. The temporal resolution is insensitive to focus-grid voltage for a narrow (50 ..mu..m) input slit, but is very sensitive to focus-grid voltage for a wide (500 ..mu..m) input slit. Spatial resolution is nearly independent of focus-grid voltage for values that give good temporal resolution. Both temporal and spatial resolution depend on the incident-light wavelength. Streak camera operation is simulated with a computer program that calculates photoelectron trajectories. Electron ray tracing describes the observed effects of slit width, incident-light wavelength, and focus-grid voltage on the output resolution. 6 refs., 10 figs., 1 tab.

Lerche, R.A.; Grasz, E.L.; Griffith, R.L.; Simpson, R.A.; Posey, R.

1987-11-01

432

Chirp Measurement of Multimode Q Switched Laser Diode Pulses by Use of a Streak Camera and a Grating Monochromator  

Microsoft Academic Search

We discuss spectrotemporal measurements of laser diode pulses performed with a streak camera and a grating monochromator to yield a precise evaluation of chirping effects in Q -switched multimode emissions. We experimentally illustrate several causes of errors, depending on the grating size and period as well as on the adjustment of the collimating lens at the monochromator output. An analytical

Alexandre Bresson; Nikolaï Stelmakh; Jean-Michel Lourtioz; Alexandre Shen; Claude Froehly

1998-01-01

433

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

NASA Astrophysics Data System (ADS)

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.

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

2011-08-01

434

1 Introduction Gazing at a flower garden through a window streaked with rain, one is aware of the  

E-print Network

1 Introduction Gazing at a flower garden through a window streaked with rain, one is aware of the properties of two surfaces in one direction, albeit at different depths. In this situation, monocular before being combined for awareness by a process that integrates over about 120 ms. A final experiment

Holcombe, Alex O.

435

Determination of shaped-jet characteristics by double orthogonal synchro streak technique and double x-ray technique  

Microsoft Academic Search

This paper presents a method that allows very accurate measurements for a full characterization of shaped charge jets. A double visualization of the jets is achieved by means of both a modified high speed camera CORDIN in Double Orthogonal Synchro Streak Technique (DOSST) configuration and a classical Double XRays Technique (DXRT). The interests of this method are twofold: Firstly, the

Robert Tosello; Mohamed Mehaddi; Henry Marrot

1995-01-01

436

Two dimensions are not better than one: STREAK and the univariate signal detection model of remember\\/know performance  

Microsoft Academic Search

We evaluated STREAK and the univariate signal detection model of Remember\\/Know (RK) judgments in terms of their ability to fit empirical data and produce psychologically meaningful parameter estimates. Participants studied pairs of words and completed item recognition tests with RK judgments as well as associative recognition tests. Fits to the RK data showed that the univariate model provided a better

Jeffrey J. Starns; Roger Ratcliff

2008-01-01

437

Computational Phlebology: The Simulation of a Vein Valve  

NASA Astrophysics Data System (ADS)

We present a three-dimensional computer simulation of the dynamics of a vein valve. In particular, we couple the solid mechanics of the vein wall and valve leaflets with the fluid dynamics of the blood flow in the valve. Our model captures the unidirectional nature of blood flow in vein valves; blood is allowed to flow proximally back to the heart, while retrograde blood flow is prohibited through the occlusion of the vein by the valve cusps. Furthermore, we investigate the dynamics of the valve opening area and the blood flow rate through the valve, gaining interesting insights into the physics of vein valve operation. It is anticipated that through computer simulations we can help raise our understanding of venous hemodynamics and various forms of venous dysfunction.

Buxton, Gavin; Clarke, Nigel

2007-03-01

438

Finger vein image quality evaluation using support vector machines  

NASA Astrophysics Data System (ADS)

In an automatic finger-vein recognition system, finger-vein image quality is significant for segmentation, enhancement, and matching processes. In this paper, we propose a finger-vein image quality evaluation method using support vector machines (SVMs). We extract three features including the gradient, image contrast, and information capacity from the input image. An SVM model is built on the training images with annotated quality labels (i.e., high/low) and then applied to unseen images for quality evaluation. To resolve the class-imbalance problem in the training data, we perform oversampling for the minority class with random-synthetic minority oversampling technique. Cross-validation is also employed to verify the reliability and stability of the learned model. Our experimental results show the effectiveness of our method in evaluating the quality of finger-vein images, and by discarding low-quality images detected by our method, the overall finger-vein recognition performance is considerably improved.

Yang, Lu; Yang, Gongping; Yin, Yilong; Xiao, Rongyang

2013-02-01

439

Portal Vein Embolization: What Do We Know?  

SciTech Connect

Portal vein embolization (PVE) has been developed to increase the size of the future remnant liver (FRL) left in place after major hepatectomy, thus reducing the risk of postoperative liver insufficiency. PVE consist in embolizing preoperatively portal branches of the segments that will be resected. Indication is based on preoperative measurements of the FRL by computed tomography and its ratio with either the theoretical liver volume or by direct measurement of the functional liver volume. After PVE, the volume and function of the FRL increases in 3 to 6 weeks, permitting extensive resections in patients otherwise contraindicated for liver resection. The PVE technique is variable from one center to another; however n-butyl-cyano-acrylate provides an interesting compromise between hypertrophy rate and procedure risk.

Denys, Alban, E-mail: Alban.Denys@chuv.ch [Centre Hospitalo Universitaire Vaudois, Department of Radiology and Interventional Radiology Unit (Switzerland); Prior, John [Centre Hospitalo Universitaire Vaudois, Department of Nuclear Medicine (Switzerland); Bize, Pierre; Duran, Rafael [Centre Hospitalo Universitaire Vaudois, Department of Radiology and Interventional Radiology Unit (Switzerland); Baere, Thierry De [Institut Gustave Roussy, Department of Interventional Radiology (France); Halkic, Nermin; Demartines, Nicolas [Centre Hospitalo Universitaire Vaudois, Department of Visceral Surgery (Switzerland)

2012-10-15

440

Vein quality in infrainguinal revascularisation: assessment by angioscopy and histology.  

PubMed Central

The concept of vein quality has been slow to gain widespread acceptance, but an increasing body of evidence suggests that vein quality is relevant to the success of bypass grafting for peripheral vascular disease. The angioscope represents an additional tool for monitoring and preparing vein grafts during infrainguinal revascularisation. Within the overall theme of vein quality, this paper presents the cumulative experience with vascular endoscopy at Bristol Royal Infirmary. In clinical studies, the diagnostic role of angioscopy in quality control was evaluated by grafting preexisting, angioscopically detected, intraluminal abnormalities and correlating them with histological appearances. There were significant associations between angioscopy/histology grades and graft patency. To enable quantification of images, an innovative computerised video image processing method has been developed and validated against simultaneous ultrasound measurements of segments of saphenous vein. The therapeutic applications of angioscopy in vein graft preparation were studied prospectively in patients undergoing in situ femoropopliteal/distal bypasses by randomisation to full angioscopic or conventional preparation. There was a significant reduction in wound morbidity. Completion angioscopy and arteriography were complementary in the detection of technical defects. Harvested vein was maintained in organ culture to assess further the influence of pre-existing pathology and the potentially traumatic effects of angioscopy on development of neointimal hyperplasia. There was a significant correlation between the extent of pre-existing abnormality and smooth muscle cell proliferative activity in culture and although angioscopy caused endothelial cell loss, this did not stimulate neointimal hyperplasia in vitro. This work confirms that vein quality can be evaluated prospectively by angioscopy and that substandard vein is associated with inferior patency rates. Angioscopic and histological evaluation, together with vein organ culture studies, have definite application in helping to elucidate the mechanisms underlying graft failure. Images Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 8 PMID:9579121

Wilson, Y. G.

1998-01-01

441

Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review.  

PubMed

The objective of the study was to review the literature reporting visual disturbance (VD) following sclerotherapy for varicose veins. Underlying mechanisms will be discussed. A literature search of the databases Medline and Google Scholar was performed. Original articles including randomized trials, case series and case reports reporting VD in humans following sclerotherapy for varicose veins were included. Additional references were also obtained if they had been referenced in related publications. The search yielded 4948 results of which 25 reports were found to meet the inclusion criteria. In larger series with at least 500 included patients the prevalence of VD following sclerotherapy ranges from 0.09% to 2%. In most reports foam sclerotherapy was associated with VD (19); exclusive use of liquid sclerosant was reported in two cases, some reports included foam and liquid sclerosant (4). There were no persistent visual disorders reported. VD occurred with polidocanol and sodium tetradecyl sulphate in different concentrations (0.25-3%). Various forms of foam preparation including various ways of foam production and the liquid - air ratio (1 or 2 parts of liquid mixed with 3, 4 or 5 parts of air) were reported in association with the occurrence of VD. VDs following sclerotherapy for varicose veins are rare and all reported events were transient. Bubble embolism or any kind of embolism seems unlikely to be the only underlying mechanism. A systemic inflammatory response following sclerotherapy has been suggested. Further research to clarify the mechanism of action of sclerosants is required. PMID:23202140

Willenberg, T; Smith, P C; Shepherd, A; Davies, A H

2012-11-30

442

Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review.  

PubMed

The objective of the study was to review the literature reporting visual disturbance (VD)following sclerotherapy for varicose veins. Underlying mechanisms will be discussed. A literature search of the databases Medline and Google Scholar was performed. Original articles including randomized trials, case series and case reports reporting VD in humans following sclerotherapy for varicose veins were included. Additional references were also obtained if they had been referenced in related publications. The search yielded 4948 results of which 25 reports were found to meet the inclusion criteria. In larger series with at least 500 included patients the prevalence of VD following sclerotherapy ranges from 0.09% to 2%. In most reports foam sclerotherapy was associated with VD (19); exclusive use of liquid sclerosant was reported in two cases, some reports included foam and liquid sclerosant (4). There were no persistent visual disorders reported. VD occurred with polidocanol and sodium tetradecyl sulphate in different concentrations (0.25–3%). Various forms of foam preparation including various ways of foam production and the liquid –air ratio (1 or 2 parts of liquid mixed with 3, 4 or 5 parts of air) were reported in association with the occurrence of VD. VDs following sclerotherapy for varicose veins are rare and all reported events were transient. Bubble embolism or any kind of embolism seems unlikely to be the only underlying mechanism. A systemic inflammatory response following sclerotherapy has been suggested. Further research to clarify the mechanism of action of sclerosants is required. PMID:23761921

Willenberg, T; Smith, P C; Shepherd, A; Davies, A H

2013-04-01

443

P552 X-Ray Streak Tube With Removable Photocathode, Improved Spatial Resolution And Temporal Fiducial  

NASA Astrophysics Data System (ADS)

We present here the P552 soft X-ray streak tube which is derived from the P500-P550 X-ray tube from RTC 1. To meet the requirements of X-ray diagnostics in high power laser interaction experiments performed at Centre d' Etudes de Limeil-Valenton some modifications were carried out to allow an easier control of the photocathode and the insertion of an optical fiducial of the laser pulse. We describe the main features of the whole device. This tube associated with a Thomson 2 TSN 505 camera has been used in laser plasma experiments and we present here some results obtained on the PHFBUS laser facility at CEL-V.

de Mascureau, J.; Bourgade, J.-L.; Mens, A.; Sauneif, R.; Rebuffie, J.-C.; Roux, J.-P.

1989-02-01

444

Characterization Of A Large-Format, High-Fidelity, Picosecond, Optical Streak Camera  

NASA Astrophysics Data System (ADS)

We have completed preliminary characterizations of a new 3-grid, large-format, ITT1 streak camera tube operating with about a 2.3-kV extraction voltage. We have found that the best attainable impulse response is 10 ps at low input intensity. However, the impulse response increases to only 30 ps with an increase of nearly three orders of magnitude in input intensity. Further, the spatial resolution remains greater than 5 line pairs/mm at 50% contrast over these three orders of magnitude of input intensity. We have also done preliminary computational modeling of the tube's temporal response as a function of focus voltage, illumina-tion spot size, and wavelength.

Lowry, Mark; Lancaster, Greg; Jander, Don; Grasz, Erna; Simpson, Bob; Lerche, Richard; Rickard, Bryan; Imhoff, C.

1988-02-01

445

Investigation of thin laser-driven flyer plates using streak imaging and stop motion microphotography  

SciTech Connect

The dynamic behavior of laser-accelerator flyers has been studied using high-speed streak imaging in combination with stop motion microphotography. With very thin targets, melting and plasma penetration of the flyer material occur in rapid sequence. The time delay from the onset of motion to flyer breakup increases with flyer thickness and decreasing incident energy. Flyer materials examined include pure aluminum (0.25-2.6 {mu}m thick) and composite targets (0.5-2.0 {mu}m thick) containing an insulating layer of aluminum oxide. While flyer breakup is observed in both types of material, the Al{sub 2}O{sub 3} barrier significantly delays the deleterious effects of deep thermal diffusion.

Frank, A.M. [Lawrence Livermore National Lab., CA (United States); Trott, W.M. [Sandia National Labs., Albuquerque, NM (United States)

1995-09-01

446

Operation and maintenance manual for LEA76-1334 compact streak camera  

SciTech Connect

This manual describes the ultra-fast streak camera which measures photon intensity vs time. The input photon wavelength range is from the near infrared of about 1.2 ..mu..m (longest usable wavelength for the S1 photo cathode) to below 100 eV x-rays (12 nm). The camera is capable of resolving events separated in time by 7 to 10 ps. The window or aperture time is adjustable from a minimum of about 1.6 ns to 50 ns or longer, with a total of 200 resolvable spots during the aperture time. The linear dynamic range of input intensity exceeds 1000 and is nominally about 2500. Included in the approximately 100 pages of the manual are specifications, precautions, operating instructions, theory of operation, checkout procedure, maintenance instructions, and other information.

Thomas, S.W.

1982-09-10

447

Microstructure investigations of streak formation in 6063 aluminum extrusions by optical metallographic techniques.  

PubMed

The present study investigates the effect of the solidification strategy for AA 6063 alloy on the surface appearance of anodized extrusions. The microstructure of the samples was analyzed using both light optical microscopy and scanning electron microscopy. Results show that if heavy segregation occurs from rapid solidification, coarse Mg2Si particles form, thus reducing the potential for precipitation strengthening by the finer ?-Mg2Si developed in the solid state. Differentially-strained regions formed during hot extrusion induce differences in particle size for magnesium silicide (Mg2Si) precipitates. Anodizing generates surface roughness due to Mg2Si particle dissolution and AlFeSi decohesion, which is related to both particle size and deformation. During anodizing, an oxide layer forms on the surface of the extruded products, which can lead to streak formation, usually a subject of rejection due to unacceptable heterogeneous reflectivity. PMID:23481588

Vander Voort, George; Suárez-Peña, Beatriz; Asensio-Lozano, Juan

2013-04-01

448

Streaked laser shadowgraphy of tungsten wire array implosions on the Saturn generator  

SciTech Connect

A combination of a 400 ns, 300 mJ, 640 nm dye laser, and an optical streak camera have been used to demonstrate that time-resolved shadowgrams can be made of the implosion phase of tungsten wire arrays. Initial experiments have shown that mirror lifetime and spatial resolution are issues for this diagnostic technique. Nonetheless, these experiments have provided new information on wire array dynamics; specifically, they show that even with a 0.46 mm wire spacing, the high density regions formed by the wires, are separate until 30 ns into the main drive current. Peak currents of 6.6 MA were obtained 40 ns after the start of the current, while peak radiated powers of 85 TW were measured at 50 ns. {copyright} {ital 1997 American Institute of Physics.}

Deeney, C.; McGurn, J.; Noack, D.; Porter, J.L.; Spielman, R.B.; Seamen, J.F.; Jobe, D.O.; Vargas, M.F.; Gilliland, T.; Douglas, M.R.; Matzen, M.K. [Sandia National Laboratory, Albuquerque, New Mexico 87185-1194 (United States)] [Sandia National Laboratory, Albuquerque, New Mexico 87185-1194 (United States)

1997-01-01

449

Solid-state ultrafast all-optical streak camera enabling high-dynamic-range picosecond recording.  

PubMed

We demonstrate an ultrafast optical recording system based on a novel optical beam deflection technique. An optical pump temporarily creates an array of prisms that deflect an optical signal beam within a GaAs/AlGaAs planar waveguide. The fabricated device yielded, to our knowledge, the fastest sustained optical deflection reported to date and was used to create spatial representations of ultrafast temporal waveforms. A conventional camera was then used to record single-shot waveforms with a 2.5 ps resolution over a 50 ps record with a dynamic range in excess of 3000:1. Through further development, this all-optical streak camera could provide insight into previously unmeasurable phenomena in many fields. PMID:20436579

Sarantos, Chris H; Heebner, John E

2010-05-01

450

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

PubMed

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. PMID:18851095

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

2008-09-01

451

Posterior Malformations in Dact1 mutant mice arise through misregulated Vangl2 at the Primitive Streak  

PubMed Central

Mice homozygous for mutations in Dact1 (Dpr/Frodo) phenocopy human malformations involving the spine, genitourinary system, and distal digestive tract. We trace this phenotype to disrupted germ layer morphogenesis at the primitive streak (PS). Remarkably, heterozygous mutation of Vangl2, a transmembrane component of the Planar Cell Polarity (PCP) pathway, rescues recessive Dact1 phenotypes, whereas loss of Dact1 reciprocally rescues semidominant Vangl2 phenotypes. We show that Dact1, an intracellular protein, forms a complex with Vangl2. In Dact1 mutants, Vangl2 is increased at the PS where cells ordinarily undergo an epithelial-mesenchymal transition. This is associated with abnormal E-cadherin distribution and changes in biochemical measures of the PCP pathway. We conclude that Dact1 contributes to morphogenesis at the PS by regulating Vangl2 upstream of cell adhesion and the PCP pathway. PMID:19701191

Suriben, Rowena; Kivimae, Saul; Fisher, Daniel A.; Moon, Randall T.; Cheyette, Benjamin N.R.

2009-01-01

452

Mapping of Digitaria streak virus transcripts reveals different RNA species from the same transcription unit.  

PubMed Central

All, except 19 [corrected] bp, of the Digitaria streak virus (DSV) genome is transcribed. Two RNA transcripts (1+ and 2+) are encoded by the virion DNA strand and up to five (1- to 5-) by the complementary DNA strand [corrected]. Detailed mapping of these RNAs has revealed evidence for splicing in one species (RNA 4-), which together with its more abundant unspliced counterpart (RNA 2-) could synthesize both a 30.5 and 41 kd polypeptide from the same transcription unit. This extensive overlapping of spliced and unspliced RNAs could indicate that the initiation and splicing of transcripts is temporally regulated. At least one transcript (RNA 1-) may have a non-translational role. Transcription of the DSV genome shows similarities to some animal DNA viruses, particularly the papovaviruses. Images PMID:2472960

Accotto, G P; Donson, J; Mullineaux, P M

1989-01-01

453

Electron streaking and dissociation in laser-assisted photoionization of molecular hydrogen  

NASA Astrophysics Data System (ADS)

We report ab initio calculations on laser-assisted photoionization of the hydrogen molecule in the energy region where autoionization from doubly excited states is expected to occur. We use a UV-pump/IR-probe scheme in which an isolated attosecond UV pulse and a 750 nm IR pulse are combined. The IR pulse has a relatively low intensity (1012 W cm-2), which allows us to perform a perturbative analysis of the calculated ionization probabilities differential in either electron or nuclear energy or both. We show that, for dissociative ionization, the electron energy distributions as a function of time delay exhibit unusual streaking patterns that are due to the presence of autoionizing states. These patterns significantly differ from the standard ones observed in direct single ionization of atoms and molecules. We also show that, by using such a pump-probe scheme, one can suppress autoionization from doubly excited states for time delays between 0 and 4 fs.

Palacios, Alicia; González-Castrillo, Alberto; Martín, Fernando

2014-06-01

454

Yellow-e Determines the Color Pattern of Larval Head and Tail Spots of the Silkworm Bombyx mori*  

PubMed Central

Yellow proteins form a large family in insects. In Drosophila melanogaster, there are 14 yellow genes in the genome. Previous studies have shown that the yellow gene is necessary for normal pigmentation; however, the roles of other yellow genes in body coloration are not known. Here, we provide the first evidence that yellow-e is required for normal body color pattern in insect larvae. In two mutant strains, bts and its allele bts2, of the silkworm Bombyx mori, the larval head cuticle and anal plates are reddish brown instead of the white color found in the wild type. Positional cloning revealed that deletions in the Bombyx homolog of the Drosophila yellow-e gene (Bmyellow-e) were responsible for the bts/bts2 phenotype. Bmyellow-e mRNA was strongly expressed in the trachea, testis, and integument, and expression markedly increased at the molting stages. This profile is quite similar to that of Bmyellow, a regulator of neonatal body color and body markings in Bombyx. Quantitative reverse transcription-PCR analysis showed that Bmyellow-e mRNA was heavily expressed in the integument of the head and tail in which the bts phenotype is observed. The present results suggest that Yellow-e plays a crucial role in the pigmentation process of lepidopteran larvae. PMID:19996320

Ito, Katsuhiko; Katsuma, Susumu; Yamamoto, Kimiko; Kadono-Okuda, Keiko; Mita, Kazuei; Shimada, Toru

2010-01-01

455

Streaked x-ray spectrometer having a discrete selection of Bragg geometries for Omegaa)  

NASA Astrophysics Data System (ADS)

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)], 10.1016/S0030-4018(96)00325-2 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.

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

2012-10-01

456

Perivascular innate immune events modulate early murine vein graft adaptations  

PubMed Central

Objective Innate immunity drives numerous cardiovascular pathologies. Vein bypass grafting procedures are frequently accompanied by low-grade wound contamination. We hypothesized that a peri-graft innate immune challenge, via an outside-in route, augments inflammatory responses, which subsequently drive a component of negative vein graft wall adaptations; moreover, adipose tissue mediates this immune response. Methods The inferior vena cava from a donor mouse was implanted into the common carotid artery of a recipient mouse utilizing a validated cuff technique (9-week-old male C57BL/6J mice). Slow-release low-dose (5 ?g) lipopolysaccharide (LPS) (n = 9) or vehicle (n = 9) was applied peri-graft; morphologic analysis was completed (day 28). In parallel, vein-grafted mice received peri-graft LPS (n = 12), distant subcutaneous LPS (n = 6), or vehicle (n = 12), then day-1 and -3 harvest of grafts and adipose tissue for cytokines and toll-like receptor (TLR) signaling mRNA expression (qRT-PCR). Results All recipient mice survived, and all vein grafts were patent. Acute low-dose local LPS challenge enhanced vein graft lumen loss (P = .04) and tended to augment intimal hyperplasia (P = .06). The surgical trauma of vein grafting universally upregulated key pro- and anti-inflammatory mediators within the day-1 graft wall, but varied on TLR signaling gene expression. Local and distant LPS accentuated these patterns until at least postoperative day 3. LPS challenge enhanced the inflammatory response in adipose tissue (locally > distantly); local LPS upregulated adipose TLR-4 dramatically. Conclusions Perivascular and distant inflammatory challenges potentiate the magnitude and duration of inflammatory responses in the early vein graft wall, negatively modulating wall adaptations, and thus, potentially contribute to vein graft failure. Furthermore, surgery activates innate immunity in adipose tissue, which is augmented (regionally > systemically) by LPS. Modulation of these local and distant inflammatory signaling networks stands as a potential strategy to enhance the durability of vascular interventions such as vein grafts. (J Vasc Surg 2013;57:486-92.) Clinical Relevance Vein graft failure is traditionally considered as a process driven by luminal hemodynamic forces and endothelial injury. We report that the “outside-in” mechanism of local perivascular and distant inflammatory challenges potentiate the magnitude and duration of inflammatory responses in the early vein graft wall, negatively modulating wall adaptations, and thus potentially contribute to vein graft failure. Modulation of these inflammatory signaling networks (eg, extension of antibiotic administration beyond standard wound prophylaxis regimens) stands as a potential strategy to enhance the durability of vascular interventions such as vein grafts. PMID:23127978

Nguyen, Binh T.; Yu, Peng; Tao, Ming; Hao, Shuai; Jiang, Tianyu; Ozaki, C. Keith

2013-01-01

457

Trace metals in fleece wool and correlations with yellowness.  

PubMed

The presence of copper and iron in metal-doped wool has been shown previously to be associated with the production of free radicals and yellowing in photo-irradiated wool. In this study, the yellowness and trace metal content of 700 wool samples was measured to determine if photoyellowing, catalysed by metals, is a major determinant of the colour of fleece wool. Iron and copper content did not positively correlate with yellowness and yellower wool tended to have lower levels of these metals. Instead, a strong positive correlation of yellowness with the calcium, manganese and magnesium content was observed in yellow wools. High levels of calcium and magnesium is consistent with biofilm formation by Pseudomonas bacteria that have previously been associated with non-scourable staining of wool. PMID:23292316

King, A L; Millington, K R

2013-03-01

458

Influence of vein fabric on strain distribution and fold kinematics  

NASA Astrophysics Data System (ADS)

Abundant pre-folding, bedding-parallel fibrous dolomite veins in shale are found associated with the Nkana-Mindola stratiform Cu-Co deposit in the Central African Copperbelt, Zambia. These monomineralic veins extend for several meters along strike, with a fibrous infill orthogonal to low-tortuosity vein walls. Growth morphologies vary from antitaxial with a pronounced median surface to asymmetric syntaxial, always with small but quantifiable growth competition. Subsequently, these veins were folded. In this study, we aim to constrain the kinematic fold mechanism by which strain is accommodated in these veins, estimate paleorheology at time of deformation and investigate the influence of vein fabric on deformation during folding. Finally, the influence of the deformation on known metallogenetic stages is assessed. Various deformation styles are observed, ultimately related to vein attitude across tight to close lower-order, hectometre-scale folds. In fold hinges, at low to average dips, veins are (poly-)harmonically to disharmonically folded as parasitic folds in single or multilayer systems. With increasing distance from the fold hinge, parasitic fold amplitude decreases and asymmetry increases. At high dips in the limbs, low-displacement duplication thrusts of veins at low angles to bedding are abundant. Slickenfibres and slickenlines are sub-perpendicular to fold hinges and shallow-dipping slickenfibre-step lineations are