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Bucher E, Millet GP, Wehrlin JP, Steiner T. Test-retest reliability of ski-specific aerobic, sprint, and neuromuscular performance tests in highly trained cross-country skiers. Scand J Med Sci Sports 2023; 33:2482-2498. [PMID: 37635277 DOI: 10.1111/sms.14473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/02/2023] [Accepted: 08/01/2023] [Indexed: 08/29/2023]
Abstract
PURPOSE Laboratory tests are commonly performed by cross-country (XC) skiers due to the challenges of obtaining reliable performance indicators on snow. However, only a few studies have reported reliability data for ski-specific test protocols. Therefore, this study examined the test-retest reliability of ski-specific aerobic, sprint, and neuromuscular performance tests. METHODS Thirty-nine highly trained XC skiers (26 men and 13 women, age: 22 ± 4 years, V̇O2max : 70.1 ± 4.5 and 58.8 ± 4.4 mL·kg-1 ·min-1 , respectively) performed two test trials within 6 days of a diagonal V̇O2max test, n = 27; skating graded exercise test to assess the second lactate threshold (LT2 ), n = 27; 24-min double poling time trial (24-min DP, n = 25), double poling sprint test (SprintDP1 , n = 27), and 1-min self-paced skating sprint test (Sprint1-min , n = 26) using roller skis on a treadmill, and an upper-body strength test (UB-ST, n = 27) to assess peak power (Ppeak ) with light, medium, and heavy loads. For each test, the coefficient of variation (CV), intraclass correlation coefficient (ICC), and minimal detectable change (MDC) were calculated. RESULTS V̇O2max demonstrated good-to-excellent reliability (CV = 1.4%; ICC = 0.99; MDC = 112 mL·min-1 ), whereas moderate-to-excellent reliability was found for LT2 (CV = 3.1%; ICC = 0.95). Performance during 24-min DP, SprintDP1 , and Sprint1-min showed good-to-excellent reliability (CV = 1.0%-2.3%; ICC = 0.96-0.99). Absolute reliability for UB-ST Ppeak was poor (CV = 4.9%-7.8%), while relative reliability was excellent (ICC = 0.93-0.97) across the loads. CONCLUSION In highly trained XC skiers, sport-specific aerobic and sprint performance tests demonstrated high test-retest reliability, while neuromuscular performance for the upper body was less reliable. Using the presented protocols, practitioners can assess within- and between-season changes in relevant performance indicators.
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Affiliation(s)
- Elias Bucher
- Section for Elite Sport, Swiss Federal Institute of Sport Magglingen, Magglingen, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Grégoire P Millet
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Jon P Wehrlin
- Section for Elite Sport, Swiss Federal Institute of Sport Magglingen, Magglingen, Switzerland
| | - Thomas Steiner
- Section for Elite Sport, Swiss Federal Institute of Sport Magglingen, Magglingen, Switzerland
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Blokker T, Bucher E, Steiner T, Wehrlin JP. Effect of cold ambient temperature on heat flux, skin temperature, and thermal sensation at different body parts in elite biathletes. Front Sports Act Living 2022; 4:966203. [PMID: 36406769 PMCID: PMC9666787 DOI: 10.3389/fspor.2022.966203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 10/07/2022] [Indexed: 01/25/2023] Open
Abstract
INTRODUCTION When exercising in the cold, optimizing thermoregulation is essential to maintain performance. However, no study has investigated thermal parameters with wearable-based measurements in a field setting among elite Nordic skiers. Therefore, this study aimed to assess the thermal response and sensation measured at different body parts during exercise in a cold environment in biathletes. METHODS Thirteen Swiss national team biathletes (6 females, 7 males) performed two skiing bouts in the skating technique on two consecutive days (ambient temperature: -3.74 ± 2.32 °C) at 78 ± 4% of maximal heart rate. Heat flux (HF), core (Tcore) and skin (Tskin) temperature were measured with sensors placed on the thigh, back, anterior and lateral thorax. Thermal sensation (TS) was assessed three times for different body parts: in protective winter clothing, in a race suit before (PRE) and after exercise (POST). RESULTS HF demonstrated differences (p < 0.001) between sensor locations, with the thigh showing the highest heat loss (344 ± 37 kJ/m2), followed by the back (269 ± 6 kJ/m2), the lateral thorax (220 ± 47 kJ/m2), and the anterior thorax (192 ± 37 kJ/m2). Tcore increased (p < 0.001). Tskin decreased for all body parts (p < 0.001). Thigh Tskin decreased more than for other body parts (p < 0.001). From PRE to POST, TS of the hands decreased (p < 0.01). CONCLUSION Biathletes skiing in a race suit at moderate intensity experience significant heat loss and a large drop in Tskin, particularly at the quadriceps muscle. To support the optimal functioning of working muscles, body-part dependent differences in the thermal response should be considered for clothing strategy and for race suit design.
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Bucher E, Torgerson PR, Hertzberg H. [Control of gastrointestinal helminths in goats in a mixed grazing system with cattle]. SCHWEIZ ARCH TIERH 2021; 163:565-576. [PMID: 34465560 DOI: 10.17236/sat00314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Due to the widespread resistance of small ruminant gastrointestinal nematodes (GIN) against anthelmintic drugs the established control strategies need to get adapted, aiming to reduce their high dependence from chemical drugs. Host-specific development of GIN can be used as a tool when grazing different species on the same pastures. The aim of this study was to estimate the effect of mixed grazing with cattle on the development of GIN infections in goats. Goat flocks with 3 heifers (Group Mix; Visp: n = 12, Chur: n = 15) and without heifers (Group Solo; Visp: n = 7, Chur: n = 15) were grazed separately on pastures at altitudes of 910 m (location Chur) and 1240 m (location Visp) above sea level resp. during one grazing season each. The composition of the mixed groups aimed to achieve a similar intake of roughage of both species. The stocking rate and the availability of roughage in the solo groups was balanced proportionately according to the situation in the mixed groups. The individual GIN egg excretion, the composition of the GIN larvae in the faeces, the FAMACHA©-Score and the pasture contamination with infective GIN larvae was determined in monthly intervals. At both sites the goats in the mixed groups showed a significantly lower mean GIN egg excretion compared with those of the Solo groups (p .
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Affiliation(s)
- E Bucher
- Institut für Parasitologie, Vetsuisse Fakultät, Universität Zürich
| | - P R Torgerson
- Abteilung für Veterinärepidemiologie, Vetsuisse-Fakultät, Universität Zürich
| | - H Hertzberg
- Institut für Parasitologie, Vetsuisse Fakultät, Universität Zürich
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Hibrand Saint-Oyant L, Ruttink T, Hamama L, Kirov I, Lakhwani D, Zhou NN, Bourke PM, Daccord N, Leus L, Schulz D, Van de Geest H, Hesselink T, Van Laere K, Debray K, Balzergue S, Thouroude T, Chastellier A, Jeauffre J, Voisine L, Gaillard S, Borm TJA, Arens P, Voorrips RE, Maliepaard C, Neu E, Linde M, Le Paslier MC, Bérard A, Bounon R, Clotault J, Choisne N, Quesneville H, Kawamura K, Aubourg S, Sakr S, Smulders MJM, Schijlen E, Bucher E, Debener T, De Riek J, Foucher F. A high-quality genome sequence of Rosa chinensis to elucidate ornamental traits. Nat Plants 2018; 4:473-484. [PMID: 29892093 DOI: 10.1101/254102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/01/2018] [Indexed: 05/27/2023]
Abstract
Rose is the world's most important ornamental plant, with economic, cultural and symbolic value. Roses are cultivated worldwide and sold as garden roses, cut flowers and potted plants. Roses are outbred and can have various ploidy levels. Our objectives were to develop a high-quality reference genome sequence for the genus Rosa by sequencing a doubled haploid, combining long and short reads, and anchoring to a high-density genetic map, and to study the genome structure and genetic basis of major ornamental traits. We produced a doubled haploid rose line ('HapOB') from Rosa chinensis 'Old Blush' and generated a rose genome assembly anchored to seven pseudo-chromosomes (512 Mb with N50 of 3.4 Mb and 564 contigs). The length of 512 Mb represents 90.1-96.1% of the estimated haploid genome size of rose. Of the assembly, 95% is contained in only 196 contigs. The anchoring was validated using high-density diploid and tetraploid genetic maps. We delineated hallmark chromosomal features, including the pericentromeric regions, through annotation of transposable element families and positioned centromeric repeats using fluorescent in situ hybridization. The rose genome displays extensive synteny with the Fragaria vesca genome, and we delineated only two major rearrangements. Genetic diversity was analysed using resequencing data of seven diploid and one tetraploid Rosa species selected from various sections of the genus. Combining genetic and genomic approaches, we identified potential genetic regulators of key ornamental traits, including prickle density and the number of flower petals. A rose APETALA2/TOE homologue is proposed to be the major regulator of petal number in rose. This reference sequence is an important resource for studying polyploidization, meiosis and developmental processes, as we demonstrated for flower and prickle development. It will also accelerate breeding through the development of molecular markers linked to traits, the identification of the genes underlying them and the exploitation of synteny across Rosaceae.
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Affiliation(s)
- L Hibrand Saint-Oyant
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Ruttink
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - L Hamama
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - I Kirov
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
- Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Moscow, Russia
| | - D Lakhwani
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - N N Zhou
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - P M Bourke
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - N Daccord
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - L Leus
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - D Schulz
- Leibniz Universität, Hannover, Germany
| | - H Van de Geest
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - T Hesselink
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - K Van Laere
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - K Debray
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Balzergue
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Thouroude
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - A Chastellier
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - J Jeauffre
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - L Voisine
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Gaillard
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T J A Borm
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - P Arens
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - R E Voorrips
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - C Maliepaard
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - E Neu
- Leibniz Universität, Hannover, Germany
| | - M Linde
- Leibniz Universität, Hannover, Germany
| | - M C Le Paslier
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - A Bérard
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - R Bounon
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - J Clotault
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - N Choisne
- URGI, INRA, Université Paris-Saclay, Versailles, France
| | - H Quesneville
- URGI, INRA, Université Paris-Saclay, Versailles, France
| | - K Kawamura
- Osaka Institute of Technology, Osaka, Japan
| | - S Aubourg
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Sakr
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - M J M Smulders
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - E Schijlen
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - E Bucher
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Debener
- Leibniz Universität, Hannover, Germany
| | - J De Riek
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - F Foucher
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France.
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Hibrand Saint-Oyant L, Ruttink T, Hamama L, Kirov I, Lakhwani D, Zhou NN, Bourke PM, Daccord N, Leus L, Schulz D, Van de Geest H, Hesselink T, Van Laere K, Debray K, Balzergue S, Thouroude T, Chastellier A, Jeauffre J, Voisine L, Gaillard S, Borm TJA, Arens P, Voorrips RE, Maliepaard C, Neu E, Linde M, Le Paslier MC, Bérard A, Bounon R, Clotault J, Choisne N, Quesneville H, Kawamura K, Aubourg S, Sakr S, Smulders MJM, Schijlen E, Bucher E, Debener T, De Riek J, Foucher F. A high-quality genome sequence of Rosa chinensis to elucidate ornamental traits. Nat Plants 2018; 4:473-484. [PMID: 29892093 PMCID: PMC6786968 DOI: 10.1038/s41477-018-0166-1] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/01/2018] [Indexed: 05/18/2023]
Abstract
Rose is the world's most important ornamental plant, with economic, cultural and symbolic value. Roses are cultivated worldwide and sold as garden roses, cut flowers and potted plants. Roses are outbred and can have various ploidy levels. Our objectives were to develop a high-quality reference genome sequence for the genus Rosa by sequencing a doubled haploid, combining long and short reads, and anchoring to a high-density genetic map, and to study the genome structure and genetic basis of major ornamental traits. We produced a doubled haploid rose line ('HapOB') from Rosa chinensis 'Old Blush' and generated a rose genome assembly anchored to seven pseudo-chromosomes (512 Mb with N50 of 3.4 Mb and 564 contigs). The length of 512 Mb represents 90.1-96.1% of the estimated haploid genome size of rose. Of the assembly, 95% is contained in only 196 contigs. The anchoring was validated using high-density diploid and tetraploid genetic maps. We delineated hallmark chromosomal features, including the pericentromeric regions, through annotation of transposable element families and positioned centromeric repeats using fluorescent in situ hybridization. The rose genome displays extensive synteny with the Fragaria vesca genome, and we delineated only two major rearrangements. Genetic diversity was analysed using resequencing data of seven diploid and one tetraploid Rosa species selected from various sections of the genus. Combining genetic and genomic approaches, we identified potential genetic regulators of key ornamental traits, including prickle density and the number of flower petals. A rose APETALA2/TOE homologue is proposed to be the major regulator of petal number in rose. This reference sequence is an important resource for studying polyploidization, meiosis and developmental processes, as we demonstrated for flower and prickle development. It will also accelerate breeding through the development of molecular markers linked to traits, the identification of the genes underlying them and the exploitation of synteny across Rosaceae.
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Affiliation(s)
- L Hibrand Saint-Oyant
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Ruttink
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - L Hamama
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - I Kirov
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
- Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Moscow, Russia
| | - D Lakhwani
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - N N Zhou
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - P M Bourke
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - N Daccord
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - L Leus
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - D Schulz
- Leibniz Universität, Hannover, Germany
| | - H Van de Geest
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - T Hesselink
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - K Van Laere
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - K Debray
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Balzergue
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Thouroude
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - A Chastellier
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - J Jeauffre
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - L Voisine
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Gaillard
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T J A Borm
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - P Arens
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - R E Voorrips
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - C Maliepaard
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - E Neu
- Leibniz Universität, Hannover, Germany
| | - M Linde
- Leibniz Universität, Hannover, Germany
| | - M C Le Paslier
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - A Bérard
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - R Bounon
- INRA, US 1279 EPGV, Université Paris-Saclay, Evry, France
| | - J Clotault
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - N Choisne
- URGI, INRA, Université Paris-Saclay, Versailles, France
| | - H Quesneville
- URGI, INRA, Université Paris-Saclay, Versailles, France
| | - K Kawamura
- Osaka Institute of Technology, Osaka, Japan
| | - S Aubourg
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - S Sakr
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - M J M Smulders
- Plant Breeding, Wageningen University & Research, Wageningen, The Netherlands
| | - E Schijlen
- Wageningen University & Research, Business Unit Bioscience, Wageningen, The Netherlands
| | - E Bucher
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France
| | - T Debener
- Leibniz Universität, Hannover, Germany
| | - J De Riek
- ILVO, Flanders Research Institute for Agriculture, Fisheries and Food, Plant Sciences Unit, Melle, Belgium
| | - F Foucher
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, Beaucouzé, France.
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Korkola JE, Watson S, Smith R, Thompson W, Dame M, Liby T, Bucher E, Sudar D, Nederlof M, Heiser L, Gray JW. Abstract PD5-01: Microenvironment microarrays show that microenvironment mediated resistance mechanisms to lapatinib differ between basal and luminal HER2+ cells. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-pd5-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cell lines represent a valuable model system for the study of breast cancer, as they capture the cellular diversity, mutational spectrum, expression subtypes, and genomic alterations that are observed in clinical specimens. However, like any model system, cell lines are imperfect, particularly when it comes to capturing the effects of the myriad of signals and interactions they encounter in their microenvironment (ME). We are utilizing a technology known as microenvironment microarrays (MEMA) to begin to unravel the consequences of interactions of breast cancer cells with the ME. MEMA consist of thousands of unique combinations of insoluble matrix proteins that are printed to form growth pads with ligands added to the media. Cells are grown on the MEMA spots and the effects of the specific ME that they are exposed to can be read out using immunofluorescent stains of interest. When combined with automated imaging and sophisticated image processing and analysis, the MEMA platform enables the identification of specific ME conditions that alter the phenotypes of cells. We have applied MEMA to understand both baseline responses to the ME as well as how the ME might mediate response to therapeutics. We performed a pilot experiment to investigate the effects of the ME on the response to the HER2-targeted inhibitor lapatinib. We found that HCC1954 cells continued to proliferate robustly in the presence of HGF when treated with 500 nM lapatinib. In contrast, AU565 cells were proliferative in the presence of NRG1 and lapatinib, but not HGF. Focused follow up studies showed that HGF is effective in rescuing only basal HER2+ cells, while NRG1 is effective in rescuing only luminal subtype HER2+cells. Rescue with the relevant growth factor was also observed in 3-d matrigel studies, showing this was not an artifact of the 2-d culture system. We investigated the effects of drug combinations using lapatinib plus drugs that target either MET (Crizotinib) or HER3-HER2 dimers (pertuzumab). These drug combinations were able to overcome the resistance mediated by HGF and NRG1 in basal and luminal cells respectively. We found the effectiveness of pertuzumab particularly interesting, given that lapatinib should still be inhibiting HER2 kinase activity. Parallel studies found that inhibitors targeting other kinase receptors such as IGF1R partially restored sensitivity to HER2 in the presence of NRG1, suggesting a role for such receptors in the resistance. Immunoprecipitation studies showed that IGF1R co-immunoprecipitated with HER2/HER3 when pertuzumab was absent, but that additional of pertuzumab abrogated the binding of IGF1R to HER3, suggesting the formation of HER2-dependent higher order structures that can signal even when HER2 is inhibited. These studies highlight the importance of understanding the effects of the ME on cancer cells, and demonstrate the differences between ME factors that can confer resistance to HER2 targeted inhibitors in basal and luminal HER2+ cells. These findings suggest that both subtype and ME composition may be important in determining response to combinatorial treatments and may be useful to inform clinical decision making.
Citation Format: Korkola JE, Watson S, Smith R, Thompson W, Dame M, Liby T, Bucher E, Sudar D, Nederlof M, Heiser L, Gray JW. Microenvironment microarrays show that microenvironment mediated resistance mechanisms to lapatinib differ between basal and luminal HER2+ cells [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD5-01.
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Affiliation(s)
- JE Korkola
- Oregon Health & Science University, Portland, OR
| | - S Watson
- Oregon Health & Science University, Portland, OR
| | - R Smith
- Oregon Health & Science University, Portland, OR
| | - W Thompson
- Oregon Health & Science University, Portland, OR
| | - M Dame
- Oregon Health & Science University, Portland, OR
| | - T Liby
- Oregon Health & Science University, Portland, OR
| | - E Bucher
- Oregon Health & Science University, Portland, OR
| | - D Sudar
- Oregon Health & Science University, Portland, OR
| | - M Nederlof
- Oregon Health & Science University, Portland, OR
| | - L Heiser
- Oregon Health & Science University, Portland, OR
| | - JW Gray
- Oregon Health & Science University, Portland, OR
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Meyer-Zehnder B, Bucher E, Vogt DR, Pargger H. [Existential questions prior to elective surgery. Survey in a preoperative anesthesia consultation service]. Anaesthesist 2016; 65:258-66. [PMID: 27033115 DOI: 10.1007/s00101-016-0153-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 02/18/2016] [Accepted: 02/19/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND Existential questions concerning the limitation of treatment must be answered when a major complication occurs after an elective operation. In these situations, the patient himself/herself cannot be asked about his/her will. Therefore, medical professionals must attempt to determine the patient's presumed will either through an existing advance directive (AD) or by consulting with the patient's relatives. Only one-fifth of all patients create an AD in advance, and the relatives cannot always reliably reproduce the patient's presumed will. Thus, it is important to talk about issues such as do-not-resuscitate before a patient undergoes elective major surgery. However, such discussions may unsettle and frighten the patient. This study aimed to determine if patients are willing to talk about difficult questions such as resuscitation before major surgery. How many patients create an AD? Who should decide when patients themselves are no longer capable? OBJECTIVES Between March 1 and October 30, 2014, patients who attended the preoperative anaesthesia consultation service received a one-page questionnaire. In addition to a few personal questions (e.g. sex, age, surgery, health status), the questionnaire included four questions that could be answered according to a four-point Likert scale, with a yes or no response, or a with a selection of answers. RESULTS 272 men (45.5%) and 321 women (53.7%) with a mean age of 52.9 years (standard deviation: 17.8 years) completed a questionnaire. 312 patients (52.2%) claimed to be healthy, while 116 patients (19.4%) observed a minimal health restriction. 125 patients (19.4%) suffered from a chronic illness that markedly (n = 108) or strongly (n = 17) limited daily life. More than three-fourths of the respondents were very ready (377/63.0%) or ready (79 patients/13.2%) to talk about the treatment of severe complications after an elective operation. 12.7% of the patients would rather not to talk about this topic (n = 47) or refused (n = 37). 58 patients (9.7%) checked the box "I do not know" or gave no answer. There was no significant difference between men and women (p = 0.58). The patient's state of health did not significantly affect the patient's willingness to talk (p = 0.61). 110 patients (18.4%) had already completed an AD. The probability of having an AD is highly dependent on the age and state of health. The likelihood of having one increases by 4% for each year of life, and in health-impaired patients it is 73% higher than in healthy ones. If the patient could no longer decide for himself/herself, the following options were selected from multiple possible answers: a relative decides (n = 272), discussing this with a physician prior to surgery (n = 212), previously created AD (n = 198), the treatment team decides (n = 28), I do not know/not (n = 48). CONCLUSIONS Although the majority of the respondents were willing to talk about difficult issues before an operation, it remains unclear to what extent these results can be generalized. However, the results justify efforts to carefully inquire about and document the will of sick patients prior to major surgery. Both the treatment team and the relatives are relieved if the patient's will is known when difficult decisions have to be made.
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Affiliation(s)
- B Meyer-Zehnder
- Departement für Anästhesie, Operative Intensivbehandlung, präklinische Notfallmedizin und Schmerztherapie, Universitätsspital Basel, Spitalstraße 21, 4031, Basel, Schweiz.
| | - E Bucher
- Departement für Anästhesie, Operative Intensivbehandlung, präklinische Notfallmedizin und Schmerztherapie, Universitätsspital Basel, Spitalstraße 21, 4031, Basel, Schweiz
| | - D R Vogt
- Clinical Trial Unit, Universitätsspital Basel, Basel, Schweiz
| | - H Pargger
- Departement für Anästhesie, Operative Intensivbehandlung, präklinische Notfallmedizin und Schmerztherapie, Universitätsspital Basel, Spitalstraße 21, 4031, Basel, Schweiz
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8
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Range KJ, Klement U, Döll G, Bucher E, Baumann JR. Notizen: The Crystal Structure of MnIn2Se4, a Ternary Layered Semiconductor. Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-1991-0825] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Single crystals of MnIn2Se4 have been grown by the chemical vapour phase transport technique using AlCl3 as the transporting agent. The structure was refined to R = 0.064, Rw, = 0.059 for 609 reflections. MnIn2Se4 (R 3̄m, hexagonal axes a = 4.051(1), c = 39.464(2) Å, c/a = 9.74, Z = 3) crystallizes with a nearly close-packed layered structure (sequence of the Se layers ABCA|CABC|BCAB) with Moct (= 0.56 Mn + 0.44 In) in octahedral coordination (Moct,–Se = 6 × 2.721(1) A) and Mtet (= 0.78 In + 0.22 Mn) in tetrahedral coordination (Mtet-Se = 1 × 2.527(2) and 3 × 2.593(1) Å). The overall layer sequences is ΑβΒαCyA| Cα AγBβC| BγCβAα B.
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Affiliation(s)
- K.-J. Range
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstraße 31, D-8400 Regensburg, Germany
| | - U. Klement
- Institut für Anorganische Chemie, Universität Regensburg, Universitätsstraße 31, D-8400 Regensburg, Germany
| | - G. Döll
- Fakultät für Physik, Universität Konstanz, Postfach 5560, D-7750 Konstanz, Germany
| | - E. Bucher
- Fakultät für Physik, Universität Konstanz, Postfach 5560, D-7750 Konstanz, Germany
| | - J. R. Baumann
- Fakultät für Physik, Universität Konstanz, Postfach 5560, D-7750 Konstanz, Germany
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Hohl H, Ramirez AP, Kaefer W, Fess K, Thurner C, Kloc C, Bucher E. A New Class of Materials with Promising Thermoelectric Properties: MNiSn (M = Ti, Zr, Hf). ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-478-109] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractTiNiSn, ZrNiSn and HfNiSn are members of a large group of intermetallic compounds which crystallize in the cubic MgAgAs-type structure. Polycrystalline samples of these compounds have been prepared and investigated for their thermoelectric properties. With thermopowers of about –200 μV/K and resistivities of a few mΩcm, power factors S2/ρ as high as 38 μW/K2 cm were obtained at 700 K. These remarkably high power factors are, however, accompanied by a thermal conductivity which is too high for applications. In order to reduce the parasitic lattice thermal conductivity, solid solutions Zrl−xHfxNiSn, Zrl−xTixNiSn, and Hfl−xTixNiSn were formed. The figure of merit of Zr0.5Hf0.5NiSn at 700 K (ZT = 0.41) exceeds the end members ZrNiSn (ZT = 0.26) and HfNiSn (ZT = 0.22).
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10
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Tributsch H, Gerischer H, Clemen C, Bucher E. On the Photopotential Output of Electrochemical Solar Cells Based on Layer-Type d-Band Semiconductors. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19790830703] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Gspan C, Grogger W, Bitschnau B, Bucher E, Sitte W, Hofer F. Crystal structure of La0.4Sr0.6CoO2.71 investigated by TEM and XRD. J SOLID STATE CHEM 2008. [DOI: 10.1016/j.jssc.2008.06.058] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Cherepanov V, Gavrilova L, Aksenova T, Ananyev M, Bucher E, Caraman G, Sitte W, Voronin V. Synthesis, structure and oxygen nonstoichiometry of La0.4Sr0.6Co1−yFeyO3−δ. PROG SOLID STATE CH 2007. [DOI: 10.1016/j.progsolidstchem.2007.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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13
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von Ungern-Sternberg BS, Regli A, Bucher E, Reber A, Schneider MC. Impact of spinal anaesthesia and obesity on maternal respiratory function during elective Caesarean section*. Anaesthesia 2004; 59:743-9. [PMID: 15270963 DOI: 10.1111/j.1365-2044.2004.03832.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Spinal anaesthesia for Caesarean section has gained widespread acceptance. We assessed the impact of spinal anaesthesia and body mass index (BMI) on spirometric performance. In this prospective study, we consecutively assessed 71 consenting parturients receiving spinal anaesthesia with hyperbaric bupivacaine and fentanyl for elective Caesarean section. We performed spirometry during the antepartum visit (baseline), immediately after spinal anaesthesia, 10-20 min, 1 h, 2 h after the operation, and after mobilisation (3 h). Baseline values were within normal ranges. There was a significant decrease in all spirometric parameters after effective spinal anaesthesia that persisted throughout the study period. The decrease in respiratory function was significantly greater in obese (BMI > 30 kg x m(-2)) than in normal-weight parturients (BMI < 25 kg x m(-2)), e.g. median (IQR) vital capacity directly after spinal anaesthesia; -24 (-16 to -31)% vs. -11 (-6 to -16)%, p < 0.001 and recovery was significantly slower. We conclude that both spinal anaesthesia and obesity significantly impair respiratory function in parturients.
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Abstract
Lumbar epidural analgesia during labour has gained widespread acceptance. The impact of epidural analgesia based on mixtures of low-dose local anaesthetic solutions and lipophilic opioids on most clinically relevant obstetric outcomes is minimal. Since the pregnant state per se is associated with important alterations in respiration, we assessed whether a subtle degree of motor blockade brought about by epidural analgesia might compromise respiratory function as assessed by spirometry. Sixty consenting parturients receiving epidural analgesia were consecutively included in this prospective study. We performed spirometry during the antepartum visit and in labour after effective epidural analgesia was established; at both assessments the women were pain-free. Values were within normal ranges but increased significantly after effective epidural analgesia; median (IQR [range]) increase for vital capacity 7.4 (3.0-13 [-12-27])% (p < 0.001); forced vital capacity 4.4 (1.7-9.8 [-13-26])% (p < 0.001); forced expiratory volume in 1 s 5.5 (1.7-8.6 [-14-28])% (p < 0.001); and peak expiratory flow rate 2.3 (-1.6-5.8 [-18-16])% (p = 0.01)). We conclude that epidural analgesia for labour significantly improved respiratory function.
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15
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Bucher E, Sitte W, Papst I, Grogger W, Hofer F. Ionische Leitfähigkeit und Mikrostruktur von La1−xSrxCoO3−δ. Z Anorg Allg Chem 2002. [DOI: 10.1002/1521-3749(200209)628:9/10<2229::aid-zaac2229>3.0.co;2-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Sitte W, Bucher E, Preis W. Transporteigenschaften von Sr‐dotiertem LaCoO
3
und LaFeO
3. Z Anorg Allg Chem 2002. [DOI: 10.1002/1521-3749(200209)628:9/10<2229::aid-zaac11112229>3.0.co;2-#] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- W. Sitte
- Institut für Physikalische Chemie, Montanuniversität Leoben, A‐8700 Leoben
| | - E. Bucher
- Institut für Physikalische Chemie, Montanuniversität Leoben, A‐8700 Leoben
| | - W. Preis
- Institut für Physikalische Chemie, Montanuniversität Leoben, A‐8700 Leoben
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18
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Sitte W, Bucher E, Benisek A, Preis W. Oxygen nonstoichiometry and ionic transport properties of La0.4Sr0.6CoO3-delta . Spectrochim Acta A Mol Biomol Spectrosc 2001; 57:2071-2076. [PMID: 11666086 DOI: 10.1016/s1386-1425(01)00489-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Homogeneous samples of La0.4Sr0.6CoO3-delta were obtained by the glycine nitrate process. The oxygen nonstoichiometry was determined from oxygen exchange measurements as a function of oxygen partial pressure (10(-4) bar < PO2 < 10(-2) bar) and temperature (300 degrees C < T< 900 degrees C). The chemical diffusion coefficient D was obtained from oxygen exchange measurements applying a stepwise variation of the oxygen partial pressure of the ambient atmosphere of a disk-shaped sample. The amount of oxygen absorbed or desorbed by the perovskite was analyzed as a function of time. Chemical diffusion data were evaluated using simplified and exact fitting procedures taking into account the surface exchange coefficient. Alternatively, galvanostatic polarization measurements were performed in a PO2-range between 10(-4) and 10(-2) bar to yield D and the ionic conductivity sigma(i) from the long time solution of the diffusion equation. Values for D from polarization measurements at T= 775 degrees C and from oxygen exchange measurements at T= 725 degrees C are in good agreement with each other. D and sigma(1) increase with increasing PO2 (10(-4) to 10(-2) bar). The ionic conductivity shows a maximum at 3-delta approximately 2.82 and decreases with decreasing oxygen content indicating the possible formation of vacancy ordered structures.
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Affiliation(s)
- W Sitte
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Austria.
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Wölfing B, Kloc C, Teubner J, Bucher E. High performance thermoelectric Tl9BiTe6 with an extremely low thermal conductivity. Phys Rev Lett 2001; 86:4350-4353. [PMID: 11328172 DOI: 10.1103/physrevlett.86.4350] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2000] [Indexed: 05/23/2023]
Abstract
Tl 9BiTe (6) exhibits a thermoelectric figure of merit of ZT approximately 1.2 around 500 K, which significantly exceeds the state-of-the-art materials in this temperature range. The extraordinary thermoelectric performance is mainly due to the extremely low thermal conductivity of Tl 9BiTe (6) [ 0.39 W/(m times K) at 300 K]. In fact, the minimum lifetime of the phonons has to be taken into account to describe the thermal conductivity data.
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Affiliation(s)
- B Wölfing
- Bell Laboratories, Lucent Technologies, Mountain Avenue, Murray Hill, New Jersey 07974, USA.
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20
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Albrecht M, Maret M, Kohler J, Gilles B, Poinsot R, Hazemann JL, Tonnerre JM, Teodorescu C, Bucher E. Ferromagnetic hcp chromium in Cr/Ru(0001) superlattices. Phys Rev Lett 2000; 85:5344-5347. [PMID: 11135992 DOI: 10.1103/physrevlett.85.5344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2000] [Indexed: 05/23/2023]
Abstract
We report the first observation of a weak ferromagnetic state of Cr in Cr/Ru(0001) superlattices, based on magnetic hysteresis and corroborated by x-ray magnetic circular dichroism at the CrL(2,3) edges. In situ reflection high-energy electron diffraction, x-ray diffraction, and Cr K-edge polarized x-ray absorption investigations have shown that the Cr layers thinner than 8 angstroms adopt a slightly distorted hcp structure, accompanied by a large atomic volume expansion of up to 14% compared to the bcc packing volume. The expanded hcp structure clearly induces the observed ferromagnetism, in agreement with theory.
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Affiliation(s)
- M Albrecht
- Department of Physics, University of Konstanz, D-78457 Konstanz, Germany.
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21
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Reinert F, Nicolay G, Eltner B, Ehm D, Schmidt S, Hufner S, Probst U, Bucher E. Observation of a BCS spectral function in a conventional superconductor by photoelectron spectroscopy. Phys Rev Lett 2000; 85:3930-3933. [PMID: 11041963 DOI: 10.1103/physrevlett.85.3930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2000] [Indexed: 05/23/2023]
Abstract
We present high-resolution photoelectron spectra on the A15-type conventional superconductor V 3Si, where-for the first time-both singularities of the BCS density of states can be resolved by photoemission spectroscopy (PES). With a transition temperature of about T(c) approximately 17 K the gap Delta(gap) of this compound has a magnitude of approximately 5 meV. A measurement by PES on this small energy scale requires a very high energy resolution (DeltaE less, similar5 meV) and sample temperatures significantly below T(c).
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Affiliation(s)
- F Reinert
- Universitat des Saarlandes, Fachrichtung 7.2-Experimentalphysik, D-66041 Saarbrucken, Germany
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22
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Bucher E, Trampuz A, Donati L, Zimmerli W. Spondylodiscitis associated with bacteraemia due to coagulase-negative staphylococci. Eur J Clin Microbiol Infect Dis 2000; 19:118-20. [PMID: 10746498 DOI: 10.1007/s100960050441] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Three cases are reported of spondylodiscitis caused by coagulase-negative staphylococci in patients without osteosynthetic material. All three patients had bacteraemia associated with an infected intravascular device left in place. On the basis of this observation, it is concluded that such devices should be removed promptly in cases of prolonged or relapsing bacteraemia. Furthermore, spondylodiscitis should be suspected in patients with back pain after bacteraemia caused by coagulase-negative staphylococci.
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Affiliation(s)
- E Bucher
- Division of Infectious Diseases, University Hospitals, Basel, Switzerland
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Abstract
Recent work on solar cells based on interpenetrating polymer networks and solid-state dye-sensitized devices shows that efficient solar-energy conversion is possible using organic materials. Further, it has been demonstrated that the performance of photovoltaic devices based on small molecules can be effectively enhanced by doping the organic material with electron-accepting molecules. But as inorganic solar cells show much higher efficiencies, well above 15 per cent, the practical utility of organic-based cells will require their fabrication by lower-cost techniques, ideally on flexible substrates. Here we demonstrate efficiency enhancement by molecular doping in Schottky-type photovoltaic diodes based on pentacene--an organic semiconductor that has received much attention as a promising material for organic thin-film transistors, but relatively little attention for use in photovoltaic devices. The incorporation of the dopant improves the internal quantum efficiency by more than five orders of magnitude and yields an external energy conversion efficiency as high as 2.4 per cent for a standard solar spectrum. Thin-film devices based on doped pentacene therefore appear promising for the production of efficient 'plastic' solar cells.
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Affiliation(s)
- J H Schon
- Bell Laboratories, Lucent Technologies, New Jersey 07974-0636, USA.
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Pardo F, de la Cruz F, Gammel PL, Bucher E, Bishop DJ. Observation of smectic and moving-Bragg-glass phases in flowing vortex lattices. Nature 1998. [DOI: 10.1038/24581] [Citation(s) in RCA: 153] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fehr T, Naim HY, Bachmann MF, Ochsenbein AF, Spielhofer P, Bucher E, Hengartner H, Billeter MA, Zinkernagel RM. T-cell independent IgM and enduring protective IgG antibodies induced by chimeric measles viruses. Nat Med 1998; 4:945-8. [PMID: 9701248 DOI: 10.1038/nm0898-945] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
B-cell activation depends on the intensity of B-cell receptor cross-linking. Studies of haptenated antigens and vesicular stomatitis virus (VSV) have demonstrated a correlation between antigen repetitiveness and the degree to which B-cell activation is independent of T cells. Here, we compare neutralizing antibody responses to inactivated VSV with those to two inactivated human pathogenic viruses: highly cytopathic poliovirus (PV) and poorly cytopathic measles virus (MV). The rigidly structured PV efficiently induced neutralizing IgM antibodies independent of T cells. In contrast, neutralizing antibodies to the pleomorphic MV were dependent on helper T cells. To test whether this resulted from the differences in virus structure or the capacity of MV to induce cell fusion and/or immunosuppression, we analyzed antibody responses to chimeric MV expressing VSV glycoprotein instead of MV fusion protein and hemagglutinin. IgM antibodies were independent of T cells; in addition, we found IgG responses dependent on T-cell help that were enduring and protective against lethal VSV infection. Because chimeric MV viruses look like MV ultrastructurally, we conclude that not only structural differences in the envelope but also the ability of MV to induce immunosuppression may limit its capacity to directly activate B cells. These findings are relevant for our understanding of B-cell activation by two prototypic human pathogenic viruses and for the design of new recombinant vaccines.
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Affiliation(s)
- T Fehr
- Institute of Experimental Immunology, University Hospital, Zürich, Switzerland
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Fehr T, Bachmann MF, Bucher E, Kalinke U, Di Padova FE, Lang AB, Hengartner H, Zinkernagel RM. Role of repetitive antigen patterns for induction of antibodies against antibodies. J Exp Med 1997; 185:1785-92. [PMID: 9151704 PMCID: PMC2196322 DOI: 10.1084/jem.185.10.1785] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Antibody responses against antibodies, such as rheumatoid factors, are found in several immunopathological diseases and may play a role in disease pathogenesis. Experience shows that they are usually difficult to induce experimentally. Antibodies specific for immunoglobulin constant regions (anti-allotypic) or for variable regions (anti-idiotypic) have been investigated in animal models; the latter have even been postulated to regulate antibody and T cell responses via network-like interactions. Why and how such anti-antibodies are induced during autoimmune diseases, has remained largely unclear. Because repetitively arranged epitopes in a paracrystalline structure of a viral envelope cross-link B cell receptors efficiently to induce a prompt T-independent IgM response, this study used immune complexes containing viruses or bacteria to evaluate the role of antigen pattern for induction of anti-antibody responses. We present evidence that antibodies bound to strictly ordered, but not to irregularly arranged, antigens dramatically enhance induction of anti-antibodies, already after a single immunization and without using adjuvants. The results indicate a novel link between anti-antibody responses and infectious agents, and suggest a similar role for repetitive self-antigens such as DNA or collagen involved in chronic immunopathological diseases.
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Affiliation(s)
- T Fehr
- Institute of Experimental Immunology, University of Zürich, CH-8091 Zürich, Switzerland
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30
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López-Macías C, Kalinke U, Fehr T, Bucher E, Zinkemagel R, Hengartner H. Induction of T-cell dependent VSV neutralizing antibodies by a fusion protein comprising VSV-G and the human IgG1 Fc portion. Immunol Lett 1997. [DOI: 10.1016/s0165-2478(97)86211-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Schön JH, Schenker O, Riazi-Nejad H, Friemelt K, Kloc C, Bucher E. Characterization of Defect Levels in Doped and Undoped CuGaSe2 by Means of Photoluminescence Measurements. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/1521-396x(199705)161:1<301::aid-pssa301>3.0.co;2-q] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Kalinke U, Krebber A, Krebber C, Bucher E, Plückthun A, Zinkernagel RM, Hengartner H. Monovalent single-chain Fv fragments and bivalent miniantibodies bound to vesicular stomatitis virus protect against lethal infection. Eur J Immunol 1996; 26:2801-6. [PMID: 8977271 DOI: 10.1002/eji.1830261202] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Several antibody-dependent mechanisms have been postulated to mediate neutralization of different animal viruses, including blocking of docking to receptors, induction of conformational changes in the virus coat, and Fc-dependent opsonization. We have studied the molecular requirements for antibody-mediated neutralization of vesicular stomatitis virus (VSV) in vitro and protection against lethal disease in vivo with a single-chain Fv fragment (scFv) and the corresponding bivalent miniantibody (scFv-dHLX) generated from a VSV-neutralizing monoclonal antibody. Both monovalent scFv and bivalent scFv-dHLX miniantibodies were able to neutralize VSV in vitro and to protect interferon-alphabeta receptor-deficient (IFN-alphabeta R-/-) mice against lethal disease after intravenous injection of 50 plaque-forming units (pfu) VSV pre-incubated with the scFv reagents. Similarly, severe-combined immunodeficient (SCID) mice infected with immune complexes of 10(8) pfu VSV and bivalent scFv-dHLX were protected against lethal disease; however, mice infected with immune complexes of 10(8) pfu VSV and monovalent scFv were not. Although repeated scFv-dHLX treatment reduced virus quantities in the blood, neither SCID nor IFN-alphabeta R-/- mice were protected against lethal disease after passive immunization and subsequent VSV infection. This was due to the short half-life of 17 min of scFv-dHLX in the circulation. These data demonstrate that neutralization of VSV and protection against lethal disease do not require Fc-mediated mechanisms and that cross-linking is not crucial for protection against physiologically relevant virus doses in vivo.
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Affiliation(s)
- U Kalinke
- Institute of Experimental Immunology, Department of Pathology, University of Zürich, Switzerland.
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D'Anna G, Gammel PL, Ramirez AP, Yaron U, Oglesby CS, Bucher E, Bishop DJ. Evidence of surface superconductivity in 2H-NbSe2 single crystals. Phys Rev B Condens Matter 1996; 54:6583-6586. [PMID: 9986676 DOI: 10.1103/physrevb.54.6583] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Claessen R, Anderson RO, Gweon G, Allen JW, Ellis WP, Janowitz C, Olson CG, Shen ZX, Eyert V, Skibowski M, Friemelt K, Bucher E, Hüfner S. Complete band-structure determination of the quasi-two-dimensional Fermi-liquid reference compound TiTe2. Phys Rev B Condens Matter 1996; 54:2453-2465. [PMID: 9986092 DOI: 10.1103/physrevb.54.2453] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Duarte A, Bolle CA, Gammel PL, Oglesby CS, Bucher E, Batlogg B, Bishop DJ. Dynamically induced disorder in the vortex lattice of 2H-NbSe2. Phys Rev B Condens Matter 1996; 53:11336-11339. [PMID: 9982746 DOI: 10.1103/physrevb.53.11336] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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37
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Arushanov E, Respaud M, Broto JM, Kloc C, Leotin J, Bucher E. Magnetic properties of beta -FeSi2 single crystals. Phys Rev B Condens Matter 1996; 53:5108-5111. [PMID: 9984102 DOI: 10.1103/physrevb.53.5108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Bucher B, Schlesinger Z, Mandrus D, Fisk Z, Sarrao J, DiTusa JF, Oglesby C, Aeppli G, Bucher E. Charge dynamics of Ce-based compounds: Connection between the mixed valent and Kondo-insulator states. Phys Rev B Condens Matter 1996; 53:R2948-R2951. [PMID: 9983892 DOI: 10.1103/physrevb.53.r2948] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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39
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Pollack L, Hoch MJ, Jin C, Smith EN, Parpia JM, Hawthorne DL, Geller DA, Lee DM, Richardson RC, Hinks DG, Bucher E. Low-temperature order in the heavy-fermion compound CeCu6. Phys Rev B Condens Matter 1995; 52:15707-15710. [PMID: 9980937 DOI: 10.1103/physrevb.52.r15707] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Yaron U, Gammel PL, Huse DA, Kleiman RN, Oglesby CS, Bucher E, Batlogg B, Bishop DJ, Mortensen K, Clausen KN, Bolle CA. Yaron et al. reply. Phys Rev Lett 1995; 75:3373. [PMID: 10059568 DOI: 10.1103/physrevlett.75.3373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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41
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Isaacs ED, Zschack P, Broholm CL, Burns C, Aeppli G, Ramirez AP, Palstra TT, Erwin RW, Stücheli N, Bucher E. Antiferromagnetism and its relation to the superconducting phases of UPt3. Phys Rev Lett 1995; 75:1178-1181. [PMID: 10060225 DOI: 10.1103/physrevlett.75.1178] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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42
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Yaron U, Gammel PL, Huse DA, Kleiman RN, Oglesby CS, Bucher E, Batlogg B, Bishop DJ, Mortensen K, Clausen KN. Structural evidence for a two-step process in the depinning of the superconducting flux-line lattice. Nature 1995. [DOI: 10.1038/376753a0] [Citation(s) in RCA: 163] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Arushanov E, Bucher E, Kloc C, Kulikova O, Kulyuk L, Siminel A. Photoconductivity in n-type beta -FeSi2 single crystals. Phys Rev B Condens Matter 1995; 52:20-23. [PMID: 9979558 DOI: 10.1103/physrevb.52.20] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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44
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Ramirez AP, Stücheli N, Bucher E. Magnetic field dependent specific heat across the middle and upper critical field lines in UPt3. Phys Rev Lett 1995; 74:1218-1221. [PMID: 10058964 DOI: 10.1103/physrevlett.74.1218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Yaron U, Gammel PL, Huse DA, Kleiman RN, Oglesby CS, Bucher E, Batlogg B, Bishop DJ, Mortensen K, Clausen K, Bolle CA. Neutron diffraction studies of flowing and pinned magnetic flux lattices in 2H-NbSe2. Phys Rev Lett 1994; 73:2748-2751. [PMID: 10057182 DOI: 10.1103/physrevlett.73.2748] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Gammel PL, Huse DA, Kleiman RN, Batlogg B, Oglesby CS, Bucher E, Bishop DJ, Mason TE, Mortensen K. Small angle neutron scattering study of the magnetic flux-line lattice in single crystal 2H-NbSe2. Phys Rev Lett 1994; 72:278-281. [PMID: 10056104 DOI: 10.1103/physrevlett.72.278] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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48
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Kleiman RN, Broholm C, Aeppli G, Bucher E, Stücheli N, Bishop DJ, Clausen KN, Mortensen K, Pedersen JS, Howard B. Neutron diffraction from the vortex lattice in the heavy-fermion superconductor UPt3. Phys Rev Lett 1992; 69:3120-3123. [PMID: 10046730 DOI: 10.1103/physrevlett.69.3120] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Gliddon MJ, Poole CA, Johannsen FH, Bucher E, Thalmann A, Dresbach C, Abramowski B. Microbiological assay of avoparcin in animal feeds and pre-mixes--co-operative study. Analyst 1992; 117:1401-5. [PMID: 1443637 DOI: 10.1039/an9921701401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A microbiological method for the determination of the antibiotic growth promoter avoparcin in animal feeds and pre-mixes was first published in 1979. The existing method has been applied to new matrices as commercial use of avoparcin has spread. Problems with the existing analytical procedure have been reported, particularly in Germany. This paper identifies the causes of the problems and includes revisions to the existing analytical procedure. The testing of these revisions in co-operative studies with up to five German official laboratories is also reported.
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Affiliation(s)
- M J Gliddon
- Product Research and Development Laboratory, Cyanamid of Great Britain Limited, Gosport, Hampshire, UK
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Mason TE, Aeppli G, Ramirez AP, Clausen KN, Broholm C, Stücheli N, Bucher E, Palstra TT. Spin gap and antiferromagnetic correlations in the Kondo insulator CeNiSn. Phys Rev Lett 1992; 69:490-493. [PMID: 10046952 DOI: 10.1103/physrevlett.69.490] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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