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31.
Unconditional quantum teleportation 总被引:5,自引:0,他引:5
A Furusawa JL Sorensen SL Braunstein CA Fuchs HJ Kimble ES Polzik 《Science (New York, N.Y.)》1998,282(5389):706-709
Quantum teleportation of optical coherent states was demonstrated experimentally using squeezed-state entanglement. The quantum nature of the achieved teleportation was verified by the experimentally determined fidelity Fexp = 0.58 +/- 0.02, which describes the match between input and output states. A fidelity greater than 0.5 is not possible for coherent states without the use of entanglement. This is the first realization of unconditional quantum teleportation where every state entering the device is actually teleported. 相似文献
32.
Real-time ultrasound imaging was used in a clinical study to estimate the number of follicles of different sizes, ovulation and conception rates, and to study follicle dynamics following oestrus-induction of bitches.
Follicles were identified during late anoestrus (between 100 and 60 days prior to the pre-ovulatory LH surge) and there appeared to be a shift in the population from small follicles (1–3 mm in diameter) to large follicles (>4 mm diameter) approximately 2 days prior to the LH surge. Corpora lutea could be reliably identified although the majority were cavitated. High ovulation rates (97–100%) and pregnant rates (86–100%) were detected, and although the conception rate was approximately 70% it varied between 8 and 92%. Within the narrow range of the clinical population studied there were trends relating age to reproduction performance. Oestrus induction with a gonadotrophin regime appeared to result in large numbers of small follicles that did not ovulate, whilst when using cabergoline the number of small and large follicels and the number of copora lutea were similar to those of control cycles. 相似文献
Follicles were identified during late anoestrus (between 100 and 60 days prior to the pre-ovulatory LH surge) and there appeared to be a shift in the population from small follicles (1–3 mm in diameter) to large follicles (>4 mm diameter) approximately 2 days prior to the LH surge. Corpora lutea could be reliably identified although the majority were cavitated. High ovulation rates (97–100%) and pregnant rates (86–100%) were detected, and although the conception rate was approximately 70% it varied between 8 and 92%. Within the narrow range of the clinical population studied there were trends relating age to reproduction performance. Oestrus induction with a gonadotrophin regime appeared to result in large numbers of small follicles that did not ovulate, whilst when using cabergoline the number of small and large follicels and the number of copora lutea were similar to those of control cycles. 相似文献
33.
Acute toxicity in five dogs after ingestion of a commercial snail and slug bait containing iron EDTA 总被引:1,自引:1,他引:0
This case series of five dogs describes the effects of ingesting large amounts of an iron EDTA snail-bait product. In all cases signs of toxicity occurred between 6 and 24 h after ingestion and included abdominal pain and haemorrhagic gastroenteritis. Two of the dogs had pretreatment serum iron levels measured and in both cases the levels were above normal limits. All of the dogs were treated with iron chelation therapy and supportive care including intravenous fluids, analgesics, gastric protectants and antibiotics. Chelation therapy with desferrioxamine mesylate did not cause adverse effects in any of the dogs and all survived to discharge. The effects of iron EDTA snail bait in dogs requires further study and minimum toxic doses need to be established. 相似文献
34.
35.
Davina Van Goethem Sebastiaan De Smedt Roland Valcke Denis O'Connor Pat O'Connell Sonja Denollin Roeland Samson Geert Potters 《世界竹藤通讯》2012,10(5):46
在寻找可再生能源和生物基材料方面,竹子已经被作为一种高产的生物质产品,可以用来作为土壤污染的修复性植物。由于这个原因,一个产量指示的增长模型需要一个健康的指标参数来检测植物的性能。因此,本研究对位于爱尔兰都伯林的Ballyboughalo公司的毛竹蒿草(Phyllostachys humilis)叶子的叶绿素荧光进行了测量。本研究测量结果涵盖了这种竹类每个节点的叶子,并且建立在了随季节性变化的基础上。最常使用的叶绿素荧光参数是Fv/Fm值,又称TRO/ABS (即被困的光子与吸收的光子数之比)。随季节的推移以及这个参数较大的变化,本研究将春天与一年中其它的季节进行对比观察测量。在过去的一年,这种植物的上部叶片比下部叶片表现更好。本研究的发现被整合在一个数学模型中,其目的是为预测和解释在其它立地条件下的植物的性能。 相似文献
36.
SL Walker RF Smith DN Jones JE Routly MJ Morris H Dobson 《Reproduction in domestic animals》2010,45(1):109-117
The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 ± 1.4 days postpartum (n = 59), including 18 non‐lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin‐releasing‐hormone (GnRH) followed by prostaglandin F2α (PG) 7 days later. Lameness shortened the period when herd‐mates attempted to mount the lame cows (1.83 ± 0.69 h vs 5.20 ± 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 ± 1.3 h vs non‐lame 15.2 ± 1.3 h). Lameness also lowered the intensity of oestrus [1417 ± 206 points (n = 18) vs 2260 ± 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd‐mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p ≤ 0.05). Fewer lame cows were observed in oestrus following PG (non‐lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd‐mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples. 相似文献
37.
38.
Résumé Au cours de la campagne d'importation de pommes de terre de consommation d'Amérique du Nord (hiver 1976–1977), près de 300
tubercules ont été analysés séparément par 3 méthodes vis-à-vis du flétrissement bactérien (Corynebacterium sepedonicum): Gram in situ. immunofluorescence (IF) in situ et isolementcaractérisation.
L'isolement est une technique peu sensible et les colonies croissent beaucoup trop lentement pour un test de détection. Le
Gram in situ se montre presque aussi sensible que l'IF et plus simple à effectuer. Néanmoins son manque de spécificité gêne
considérablement la détection, en particulier sur des tubercules décomposés. L'IF ne pose pas de problème de spécificité sérologique
avec la flore des tubercules, exception faite d'une réaction commune et réciproque avecErwinia carotovora var.atroseptica.
Ne pouvant pas déterminer le niveau de tolérance, ce qui ne peut se réaliser qu'en pays contaminé. nous avons fixé un seuil
arbitraire de positivité du test IF, supérieur au bruit de fond de la méthode.
Summary During the winter 1976–1977, ware potatoes were imported from North America. About 300 tubers with and without visible symptoms were tested for the presence ofCorynebacterium sepedonicum, using 3 methods: Gram staining in situ, immunofluorescent staining (IF) in situ and isolation-characterization. In each case the heel end of the tuber was peeled and the net of vascular bundles removed and cut into 1-mm long pieces in sterile water. Three drops of extract from the same tuber were tested comparatively. Isolation was made on an enriched medium (21 C, 15 to 20 days) and the bacteria characterized on the basis of cultural features. Gram staining. behaviour on Hugh and Leifson glucose medium and hypersensitive reaction on tobacco. IF staining was performed by the indirect method. withC. sepedonicum anti-serum (INRA-CNBP 1154=NCPPB 1499) diluted to 1–200. The result of a smear was based on the estimated number of fluorescent bacteria in 200 microscope fields. Isolation was by far the least sensitive method for the detection ofC. sepedonicum (22 postitive tubers (Table 1)) and the colonies were too slow growing for a detection test (10 to 21 days). Gram staining was roughly as sensitive as IF (41 positive tubers (Table 2)) and easier to perform. Nevertheless, its lack of specificity prevented reliable detection, particularly in degraded tubers invaded by numerous Gram-positive coccoid bacteria (Lactobacillaceae). IF staining showed high serological specificity against other tuber flora (200 bacteria tested), except for a reciprocal serological reaction withErwinia carotovora var.atroseptica found in 9 tubers. In tuber tissue,C. sepedonicum appeared much smaller thanErwinia and coccoid: IF staining was less intense with both heterologous sera. For routine detection. absorption of the common antibodies may be necessary. Regarding visible symptoms: some apparently healthy tubers yieldedC. sepedonicum (Gram. IF, even isolation), whereas many tubers showing brown vascular fibers were free ofC. sepedonicum, typical symptoms being a broad shiny yellow vascular ring, then, in an ultimate phase, detachment of the cortex of the tuber with complete degradation of vascular tissues often accompanied by a corky reaction. Unfortunately, facilities for eggplant bioassay were not available at the time. Without knowing the tolerance level (number of bacteria in the seed tuber below which the disease does not appear even under optimal conditions), a threshold that could only be determined in a country in which the disease was endemic, we settled for an arbitrary level of positive response to the IF test (if in 200 microscope fields, a positive smear showed more than 1 fluorescent bacterium per field on average), higher than the background of the method. We noticed that in the majority of positive tests (even without visible tuber symptoms) the smears showed from 100 to 500 fluorescent bacteria per microscope field. The IF test may be successfully used to detectC. sepedonicum in seed tubers. During that winter of 1976–1977, 7 consignments of ware potatoes were intercepted at French ports. 6 were shipped from Maine (USA) and 1 from New Brunswick (Canada) (Table 3).
Zusammenfassung W?hrend des Winters 1976–1977 wurden Speisekartoffeln aus Nordamerika importiert. Ungef?hr 300 Knollen, welche zum Teil sichtliche Symptome vonCorynebacterium sepedonicum aufwiesen, wurden nach 3 verschiedenen Methoden untersucht: Gram-F?rbung in situ. Immunofluoreszenz (IF) in situ und Bestimmung nach Isolierung. Vom gesch?lten Nabelende der Knolle wurde die Gef?ssbündelpartie entnommen und in sterilem Wasser in Fragmente von 1 mm geschnitten. Zum Vergleich wurden 3 Tropfen desselben Extraktes untersucht. Die Isolierung wurde auf einem angereicherten Milieu vorgenommen (21 C, 15 bis 20 Tage): dann wurden die Bakterien bestimmt aufgrund ihres Kulturzustandes. Gram-F?rbung. Verhalten in Hugh und Leifsonglukose und Hypersensibilit?treaktion auf Tabak. Die IF wurde nach der indirekten Methode untersucht, mit einem anti-C. sepedonicum-Serum (INRA-CNBP 1154=NCPPB 1499) auf 1–200 verdünnt. Die Ergebnisse eines Pr?parates wurden bonitiert durch Sch?tzung der Anzahl fluoreszierender Bakterien in 200 Mikroskopiefeldern. Die Isolierung ist eine schwach empfindliche Methode fürC. sepedonicum (22 positive Knollen, siehe Tabelle 1), und die Kolonien wachsen zu langsam für einen Befallsbestimmungstest (10 21 Tage). Die Methode der Gram-F?rbung in situ scheint gleich empfindlich wie die IF (41 positive Knollen, siehe Tabelle 1) und ist leichter durchführbar. Die Unspezifizit?t dieser Methode st?rt jedoch bei der Bestimmung, vor allem bei faulen Knollen in denen viele kokkenf?rmige Gram-positive Bakterien wachsen (Lactobacillaceae). Die IF-Methode bereitet keine Schwierigkeiten bezüglich der serologischen Spezifizit?t der Knollenflora (200 Bakterienkulturen wurden getestet) mit Ausnahme einer gemeinsamen und reziproken Reaktion mitErwinia carotovora var.atroseptica. In den Geweben istC. sepedonicum kleiner alsErwinia und kokkenf?rmig; die IF-Reaktion erscheint mit einer geringeren Intensit?t. Vermutlich ist für Routinebestimmung die Absorption dieser gemeinsamen Antik?rper notwendig. Was die sichtbaren Symptome betrifft. wurden alle Stadien beobachtet: scheinbare gesunde Knollen zeigtenC. sepedonicum (Gram, IF, manchmal Isolierung); viele Knollen mit braun gef?rbtem Gef?ssbündel waren jedoch frei vonC. sepedonicum: die typischen sichtbaren Symptome sind haupts?chlich ein verdickter, gelbgl?nzender Gef?ssbündelring, welcher sich in einem vorgerückten Stadium vom Rest der Knollen l?st, nach kompleter Zerst?rung des Gewebes der Gef?ssbündelpartie: manchmal wurden auch Korkbildungsreaktionen beobachtet. Leider konnte der biologische Test auf Eierpflanzen zu diesem Zeitpunkt nicht durchgeführt werden. Da die Toleranzgrenze nicht bekannt ist (Anzahl Bakterien in einer Pflanzknolle, unter welcher keine Welkung auftritt, auch unter optimalen Bedingungen) — diese kann nur in einem Lande mit Befall untersucht werden haben wir eine willkürliche Grenze der Positivit?t des IF-Testes angesetzt (Untersuchung von 200 Mikroskopiefelder, auf einem positiven Pr?parat befinden sich im Mittel mehr als 1 fluoreszierendes Bakterium) h?her als die Hintergrundfluoreszenz. Wir haben beobachtet. dass in den meisten positiven Pr?paraten (auch von Knollen ohne sichtbare Symptome) 100–500 fluoreszierende Bakterien pro Feld auftreten. Der IF-Test kann mit Erfolg für den Nachweis vonC. sepedonicum in Saatknollen angewendet werden. W?hrend des Winters 1976–1977 wurden 7 Schiffsladungen in den franz?sischen H?fen beschlagnahmt, 6 kamen vom Staat Maine (USA) und 1 von New-Brunswick (Kanada) (siehe Tabelle 3).相似文献
39.
Species of Trichocomaceae occur commonly and are important to both industry and medicine. They are associated with food spoilage and mycotoxin production and can occur in the indoor environment, causing health hazards by the formation of β-glucans, mycotoxins and surface proteins. Some species are opportunistic pathogens, while others are exploited in biotechnology for the production of enzymes, antibiotics and other products. Penicillium belongs phylogenetically to Trichocomaceae and more than 250 species are currently accepted in this genus. In this study, we investigated the relationship of Penicillium to other genera of Trichocomaceae and studied in detail the phylogeny of the genus itself. In order to study these relationships, partial RPB1, RPB2 (RNA polymerase II genes), Tsr1 (putative ribosome biogenesis protein) and Cct8 (putative chaperonin complex component TCP-1) gene sequences were obtained. The Trichocomaceae are divided in three separate families: Aspergillaceae, Thermoascaceae and Trichocomaceae. The Aspergillaceae are characterised by the formation flask-shaped or cylindrical phialides, asci produced inside cleistothecia or surrounded by Hülle cells and mainly ascospores with a furrow or slit, while the Trichocomaceae are defined by the formation of lanceolate phialides, asci borne within a tuft or layer of loose hyphae and ascospores lacking a slit. Thermoascus and Paecilomyces, both members of Thermoascaceae, also form ascospores lacking a furrow or slit, but are differentiated from Trichocomaceae by the production of asci from croziers and their thermotolerant or thermophilic nature. Phylogenetic analysis shows that Penicillium is polyphyletic. The genus is re-defined and a monophyletic genus for both anamorphs and teleomorphs is created (Penicillium sensu stricto). The genera Thysanophora, Eupenicillium, Chromocleista, Hemicarpenteles and Torulomyces belong in Penicilliums. str. and new combinations for the species belonging to these genera are proposed. Analysis of Penicillium below genus rank revealed the presence of 25 clades. A new classification system including both anamorph and teleomorph species is proposed and these 25 clades are treated here as sections. An overview of species belonging to each section is presented. TAXONOMIC NOVELTIES: New sections, all in Penicillium: sect. Sclerotiora Houbraken & Samson, sect. Charlesia Houbraken & Samson, sect. Thysanophora Houbraken & Samson,sect. Ochrosalmonea Houbraken & Samson, sect. Cinnamopurpurea Houbraken & Samson, Fracta Houbraken & Samson, sect. Stolkia Houbraken & Samson, sect. Gracilenta Houbraken & Samson, sect. Citrina Houbraken & Samson, sect. Turbata Houbraken & Samson, sect. Paradoxa Houbraken & Samson, sect. Canescentia Houbraken & Samson. New combinations:Penicillium asymmetricum (Subramanian & Sudha) Houbraken & Samson, P. bovifimosum (Tuthill & Frisvad) Houbraken & Samson, P. glaucoalbidum (Desmazières) Houbraken & Samson, P. laeve (K. Ando & Manoch) Houbraken & Samson, P. longisporum (Kendrick) Houbraken & Samson, P. malachiteum (Yaguchi & Udagawa) Houbraken & Samson, P. ovatum (K. Ando & Nawawi) Houbraken & Samson, P. parviverrucosum (K. Ando & Pitt) Houbraken & Samson, P. saturniforme (Wang & Zhuang) Houbraken & Samson, P. taiwanense (Matsushima) Houbraken & Samson. New names:Penicillium coniferophilum Houbraken & Samson, P. hennebertii Houbraken & Samson, P. melanostipe Houbraken & Samson, P. porphyreum Houbraken & Samson. 相似文献
40.
N. Van den Bilcke K. Alaerts S. Ghaffaripour D. J. Simbo R. Samson 《Genetic Resources and Crop Evolution》2014,61(2):537-553
Tamarind (Tamarindus indica L.) is a tropical fruit tree highly valued for its fruit pulp. It has been identified as one of the priority species with great potential for domestication in the Sahelian countries of Sub-Saharan Africa. An important step in the domestication process is the characterization of the local natural variation of the species in order to select the most interesting phenotypes/genotypes which possess several desired traits for breeding purposes. Four provenances covering contrasting agro-ecological zones in Mali were selected for fruit morphological and nutritional traits (tartaric acid and sugars). Tamarind trees from the driest provenance contained smaller fruits with a smaller amount of pulp compared to provenances from wetter zones. Tamarind trees in Mali have a low real pulp value (maximum 9.5) and bear sour fruits (high tartaric acid content of 9–12 %). Some sweet-fruited trees could be identified, but the sweetness was low (maximum 8). Fruit traits seem to be influenced by climate and soil characteristics, which should be taken into account in the domestication process, when planting trees in a different region of origin. We selected a few elite trees within each provenance, containing the best combination for the most desirable fruit traits, using web diagrams. Frequency distributions of the different fruit traits showed some traits are probably the target of selection by farmers. All provenances, except the driest one, indicated a possible very first stage of domestication. 相似文献