Littérature scientifique sur le sujet « Tripletti »
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Articles de revues sur le sujet "Tripletti"
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Egic, Amira, Zeljko Mikovic, Dejan Filimonovic et Anka Cirovic. « Birth weight discordance and perinatal mortality among triplets ». Srpski arhiv za celokupno lekarstvo 133, no 5-6 (2005) : 254–57. http://dx.doi.org/10.2298/sarh0506254e.
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INTRODUCTION. The incidence of multiple births has increased in the last decade. Perinatal mortality in triplets is significantly greater than in twin and singleton births. OBJECTIVE. The objective of this study was to describe the extent of birth weight discordance among triplets and to identify its association with an increased risk of perinatal mortality. METHOD A retrospective analysis of triplet births, for the period 1993-2003, was conducted at the Gynaecological-Obstetric Clinic "Narodni Front" in Belgrade. Birth weight discordance was defined as the difference in birth weight between the largest and the smallest triplet's weight of more than 20%. RESULTS. The rate of triplets has increased by almost 75% between the first (7.7%) and the last (29.6%) 5-year period of the last decade. Triplets are becoming more common because of the frequent use of assisted reproductive technology as a treatment for infertility. In the period 1993-2003, there were a total of 40 triplet live births (24 weeks and greater) with incidence of 0.06%. There was no clear association between maternal age, parity, method of conception, birth gestational age, and disorders complicating pregnancy with birth discordance more than 20%. Regarding birth weight groups, statistical significance occurred only in the <999 grams group for discordant and in the 2000-2499 grams group for concordant triplets. Overall, the perinatal mortality rate in the group was 10.8%, the foetal mortality rate was 1.7% (2/120), and the neonatal (0-28 days) mortality rate was 9.1% (11/120). An odds ratio of 95% confidence interval shows 3 times greater risk for adverse perinatal outcome in the discordant group. However, the difference was not significant. CONCLUSION. Increasing birth weight discordance may increase the risk of adverse perinatal outcome. Triplet pregnancies, being high risk, require intensive antenatal care in order to prevent preterm delivery and ultrasound in order to diagnose foetal growth abnormality and discordance, which increase foetal surveillance, through the use of biophysical profiles, non-stress tests, and Doppler velocimetry, thus assessing foetal well-being and the appropriate moment for obstetric intervention.
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Fennessy, Kristy M., Lex W. Doyle, Kentia Naud, Karen Reidy et Mark P. Umstad. « Triplet Pregnancy : Is the Mode of Conception Related to Perinatal Outcomes ? » Twin Research and Human Genetics 18, no 3 (30 avril 2015) : 321–27. http://dx.doi.org/10.1017/thg.2015.27.
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Many triplets are conceived as a consequence of assisted reproductive technology (ART). Concerns have been raised that triplet pregnancies conceived by ART are more complicated than those conceived spontaneously. The purpose of this study was to evaluate all triplet pregnancies managed over a 12-year period to determine if there were any differences in outcome based on the mode of conception. All triplet pregnancies between 1999 and 2011 that reached at least 20 weeks’ gestation and that were managed at the Royal Women's Hospital (RWH), Melbourne, Victoria were identified. Maternal and neonatal outcomes were compared between ART conceived and spontaneously conceived triplets. In the study period, 53 sets of triplets managed in our institution met the eligibility criteria. Twenty-five triplet sets were conceived by ART and 28 were conceived spontaneously. More ART conceptions resulted in trichorionic triamniotic (TCTA) triplets than did spontaneous conceptions (p= .015). There were no differences between ART and spontaneously conceived triplets for any of the maternal or neonatal complications studied. Trichorionic (TC) triplets delivered at a later gestation than other triplets: 32.1 (SD2.9) versus 30.4 (SD3.9) weeks (p= .08). TC triplets were significantly less likely to die than monochorionic (MC) or dichorionic (DC) triplets: 3/93 (3%) versus 13/66 (20%) (p= .025). In conclusion, triplets conceived by ART are more likely to have TCTA placentation and TCTA triplet sets had lower mortality rates than other triplet combinations. Outcomes for triplets conceived by ART were similar to those of triplets conceived spontaneously.
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Eriksson, A. W. « President's Address : Twinning in Families of Triplets ». Acta geneticae medicae et gemellologiae : twin research 39, no 3 (juillet 1990) : 279–93. http://dx.doi.org/10.1017/s0001566000005195.
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AbstractA study was conducted on twinning in relatives of consecutive triplet sets in the Åland Islands in the years 1740-1939. The incidence of twinning in sibships of triplets was extremely high, 80/1000 (56/1000 before and 143/1000 after the triplet maternity). In Finland as a whole, 1905-1954, the twinning rate was among mothers of triplets 38/1000, ie, about 2.6 times the rate in general population, and was higher after (48/1000) than before the triplet maternity (34/1000). In the sibships of fathers of triplets there was a low rate of twinning (below 10/1000) both of same-sexed (SS) and of opposite-sexed (OS) triplets. Among sibships of mothers of OS triplets the twinning rate was 18/1000 and among mothers' sibships of SS triplets 26/1000. The series of triplet families from both Åland and Finland as a whole indicate a considerably higher frequency of twinning on the maternal than on the paternal side. The sibships of OS triplets in Finland have higher twinning rates than sibships of SS triplets (50/1000 vs 27/1000). In sibships of triplets, not only the DZ but also the MZ twinning rates were approximately twice as high as those in the general population. The triplet rates in Finland were increasing strongly with maternal age and were in the last century among mothers of 30-39 years of age considerably higher than among mothers from this century. This, in combination with higher mean parity, may explain the high rates of multiple maternities in sibships of triplets in the past. The rate of triplet maternities seems to be more sensitive to sociodemographic changes than the rate of twin maternities. Mothers of triplets in Finland had a high frequency (more than 40%) of prenuptially conceived firstborn children. This, and a short protogenesic interval indicate that triplet-prone mothers are more fecundable, ie, they conceive with greater ease and/or may have a better physical condition than other women for completing a gestation with multiple embryos.
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Merz, Maximilian, Vishal Patel, Lucie Kutikova, Andrea Lebioda, Martina Schoehl, Lenka Kellermann et Hartmut Goldschmidt. « Treatment Patterns in Patients (pts) with Refractory/Relapsed Multiple Myeloma (RRMM) in Germany between 2016 and 2018 ». Blood 134, Supplement_1 (13 novembre 2019) : 4734. http://dx.doi.org/10.1182/blood-2019-128030.
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Background: The RRMM treatment landscape has increased in complexity in recent years due to the availability of novel agents. In this study, we evaluated treatment patterns over 3 years in real-world RRMM pts treated with regimens containing one or more of the following agents: carfilzomib (K), bortezomib (V), lenalidomide (R), pomalidomide (P), ixazomib (I), daratumumab (D), and elotuzumab (E). Methods: We retrospectively analysed data from a German longitudinal database (TherapyMonitor) for pts receiving RRMM treatment (2nd-line [2L] and beyond) between January 2016 and December 2018. Patient demographics, treatment details and clinical characteristics were described by line of treatment and regimen for a patients most recent treatment. Treatment patterns were described by year of treatment initiation (2016, 2017 or 2018). Results: Of the total study population of 2033 RRMM pts, the most recent treatment line was 2L for 1047 and 3L+ for 986 pts. 2L/3L+ pts had a median age of 70/71 years (22%/27% >75 years; most were aged 66-75 years); 57%/61% had ISS stage III; 43%/50% had ECOG ≥2; 10%/9% had renal dysfunction; 56%/56% had ≥1 comorbidity and 14%/17% had received stem cell transplantation at 1L, respectively. In 2L pts, across 2016-2018, R non-triplet (24%) was the most common treatment regimen, with 18% and 10% of pts receiving K+R and D+R triplets, respectively. In 3L+ pts, the most common treatment regimens were D-based (29% [12% non-triplet, 9% D+V triplet and 8% D+R triplet]), P non-triplet (9%), K non-triplet or I/R triplet (both 8%), and R non-triplet (7%). In 2L pts, the most frequent prior treatments were V triplets/non-triplets (45%/19%) and R non-triplets (15%). In 3L+ pts, the most frequent prior treatments were R non-triplets (27%) and K non-triplets (16%). Triplet regimens were mostly administered in 2L to pts ≤65 years. Age had no clear impact on 3L+ treatment patterns. ECOG status impacted treatment patterns in 2L (doublet therapy more frequent in ECOG ≥2) but not in 3L+ (most pts had ECOG ≥2 but were frequently treated with E/D/I triplets). Regarding trends over time (2016 to 2018), considering all treatments, V triplet+ was the most frequently used regimen prior to 2L (37 to 43%), while V-non-triplet use decreased (32% to 19%) and R-based non-triplet use doubled (7% to 16%). In 2L, K-based regimen use increased from 25% to 38%, mainly due to increased use of K non-triplet (10% to 19%). 2L D-based triplet use increased from 0% to 15% and use of R non-triplet halved (55% to 27%). Patients receiving K- or D-based triplet or R non-triplet at 2L predominantly received V triplet regimens at 1L. Most 2L pts receiving non-triplet regimens also received V or R non-triplets at 1L. These trends suggest a shift in use of R non-triplets from 2L to 1L, replacing 1L V non-triplets and resulting in greater use of 2L K non-triplets. Specifically, for 2L in 2018, of the 27% of pts treated with R non-triplets (Figure), the most common 1L regimens were V-triplet (44%), V non-triplet (29%) and other non-novel agent containing regimens (15%). For the 19% of pts receiving 2L K+R triplet regimen, the most common 1L regimens were V-triplet+ (66%), other regimens containing novel agents (24%) and V and R non-triplets (5% each). Of the 19% of pts receiving 2L K non-triplet regimens, R non-triplet (35%), V non-triplet (28%) and V-triplet+ (24%) were the most common 1L treatments. For the 11% of pts receiving 2L DR-triplet regimens, V-triplet+ (57%), other regimens containing novel agents (20%), R non-triplet (14%), and V non-triplet (6%) were the most common 1L treatments. Conclusions: Multiple approvals of novel RRMM agents in Europe resulted in changes in the treatment landscape, with a more immediate impact in countries with earlier access to new drugs. In this RRMM population we found increased 1L use of R non-triplets and decreased V non-triplet use between 2016-2018. Use of D-based regimens increased in 2L; P-, I-, and E-based regimens were infrequently used in 2L (≤4% in 2018). Pts receiving 1L non-triplets generally received 2L non-triplet treatment; those receiving 1L triplet generally also received 2L triplet treatment. 3L pts were mostly R-pretreated due to high use of 2L R-based triplets. Germany may serve as an example for the adoption of novel treatments as there is adoption of all RRMM agents approved since 2016. Figure Disclosures Merz: Takeda Vertrieb GmbH: Other: Travel grants, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees, Other: Travel grants; Janssen: Other: Travel grants; Abbvie: Other: Travel grants; Celgene: Other: Travel grants. Patel:Amgen: Employment. Kutikova:Amgen: Employment. Lebioda:Amgen: Employment. Schoehl:Amgen: Employment. Kellermann:Takeda: Research Funding; Amgen: Research Funding; BMS: Research Funding; Celgene: Research Funding; Janssen: Research Funding; Sanofi: Research Funding. Goldschmidt:Dietmar-Hopp-Stiftung: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Chugai: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Molecular Partners: Research Funding; MSD: Research Funding; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Mundipharma: Research Funding; Janssen: Consultancy, Research Funding; John-Hopkins University: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive Biotechnology: Membership on an entity's Board of Directors or advisory committees; John-Hopkins University: Research Funding.
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Lamb, Diane J., Jacqueline M. Vink, Christel M. Middeldorp, Catharina E. M. van Beijsterveldt, Monique C. Haak, Lucy I. H. Overbeek et Dorret I. Boomsma. « Effects of Chorionicity and Zygosity on Triplet Birth Weight ». Twin Research and Human Genetics 15, no 2 (28 mars 2012) : 149–57. http://dx.doi.org/10.1375/twin.15.2.149.
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Birth weight in triplets is, on average, lower than in singletons and twins, and more children are classified as having very low or extremely low birth weight. Still, there is limited research on factors that affect triplet birth weight, and samples under study are often small. Chorionicity and zygosity influence triplet birth weight, but it is unknown whether the effect of zygosity can be entirely ascribed to the effect of chorionicity or whether zygosity has an additional effect on triplet birth weight. This question was investigated in 346 triplets (from 116 trios) registered with the Netherlands Twin Register for whom data on chorionicity were available. ‘Triplet’ refers to one child and the set of three triplets is referred to as ‘trio’. Trios and triplets were classified based on zygosity and chorionicity. With regression analysis, the effects of zygosity and chorionicity on triplet birth weight were examined, while controlling for gestational age, sex, and maternal smoking during pregnancy. In addition, within the dizygotic trios a within-family comparison was made between the birth weight of the triplets that were part of a monozygotic pair (with some pairs sharing a chorion), and the birth weight of the dizygotic triplet. Based on the classification on individual level, monozygotic, monochorionic triplets had a lower mean birth weight than dizygotic, dichorionic triplets. Most remarkably, in dizygotic trios, monozygotic pairs only had a lower mean birth weight than their dizygotic sibling triplet when the pair shared a chorion. We conclude that having shared a chorion, rather than being monozygotic, increases the risk of a low birth weight.
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Strube, Michael J. « What Did Triplett Really Find ? A Contemporary Analysis of the First Experiment in Social Psychology ». American Journal of Psychology 118, no 2 (1 juillet 2005) : 271–86. http://dx.doi.org/10.2307/30039059.
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Abstract In 1898, Norman Triplett published was has been called the first experiment in social psychology and sports psychology. Claiming to demonstrate "the dynamogenic factors in pacemaking and competition," this oft-cited article began the serious investigation of social facilitation. This area of research now numbers in the hundreds of published works, includes the study of humans and other animals, and encompasses basic research and applied settings. But what did Triplett really find? I examine Triplett’s original data and show that very little evidence existed for the social facilitation of the simple task he investigated. These analyses indicate the need to correct contemporary accounts of Triplett’s work and underscore the differences in how research was evaluated at that time compared with today.
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Han, Huixia, Xinyue Li et Kaijun Wu. « Op-Trans : An Optimization Framework for Negative Sampling and Triplet-Mapping Properties in Knowledge Graph Embedding ». Applied Sciences 13, no 5 (22 février 2023) : 2817. http://dx.doi.org/10.3390/app13052817.
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Knowledge graphs are a popular research field in artificial intelligence, and store large amounts of real-world data. Since data are enriched over time, the knowledge graph is often incomplete. Therefore, knowledge graph completion is particularly important as it predicts missing links based on existing facts. Currently, the family of translation models delivers a better performance in knowledge graph completion. However, most of these models randomly generate negative triplets during the training process, resulting in the low quality of negative triplets. In addition, such models ignore the important characteristics of triplet-mapping properties during model learning. Therefore, we propose an optimization framework based on the translation models (Op-Trans). It enhances the knowledge-graph completion effect from both negative sampling and triplet-mapping properties. First, we propose a clustering cache to generate negative triplets, which generate negative triplets based on entity similarity. This sampling method can directly use the cache to track the negative triplets with large scores. In addition, we focus on the different contributions of the triplets to the optimization goal. We calculate the distinct weight for each triplet according to its mapping properties. In this way, the scoring function deals with each triplet depending on its own weight. The experimental results show that Op-Trans can help the state-of-the-art baselines to obtain a better performance in a link prediction task.
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Poorheravi, Parisa Abdolrahim, Benyamin Ghojogh, Vincent Gaudet, Fakhri Karray et Mark Crowley. « Acceleration of Large Margin Metric Learning for Nearest Neighbor Classification Using Triplet Mining and Stratified Sampling ». Journal of Computational Vision and Imaging Systems 6, no 1 (15 janvier 2021) : 1–5. http://dx.doi.org/10.15353/jcvis.v6i1.3534.
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Metric learning is a technique in manifold learning to find a projection subspace for increasing and decreasing the inter- and intra-class variances, respectively. Some metric learning methods are based on triplet learning with anchor-positive-negative triplets. Large margin metric learning for nearest neighbor classification is one of the fundamental methods to do this. Recently, Siamese networks have been introduced with the triplet loss. Many triplet mining methods have been developed for Siamese nets; however, these techniques have not been applied on the triplets of large margin metric learning. In this work, inspired by the mining methods for Siamese nets, we propose several triplet mining techniques for large margin metric learning. Moreover, a hierarchical approach is proposed, for acceleration and scalability of optimization, where triplets are selected by stratified sampling in hierarchical hyper-spheres. We analyze the proposed methods on three publicly available datasets.
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Pedrini, Jacopo, Angelo Monguzzi et Francesco Meinardi. « Cascade sensitization of triplet–triplet annihilation based photon upconversion at sub-solar irradiance ». Physical Chemistry Chemical Physics 20, no 15 (2018) : 9745–50. http://dx.doi.org/10.1039/c8cp01176a.
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Feingold, M., C. Cetrulo, M. Peters, A. Chaudhury, S. Shmoys et O. Geifman. « Mode of Delivery in Multiple Birth of Higher Order ». Acta geneticae medicae et gemellologiae : twin research 37, no 1 (janvier 1988) : 105–9. http://dx.doi.org/10.1017/s0001566000004323.
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AbstractA retrospective review of triplets delivered at a Boston perinatal center from 1977 to 1986 was performed. Comparison was made between this group (study group) and previously published data on triplets in our institution (control group). Since 1977 there was a more liberal use of abdominal delivery. Cesarean sections (CS) of all triplets with malpresentation was our protocol. Of the 15 sets of triplet pregnancies in the study group, 11 were delivered by CS and 4 by vaginal delivery, vs only 1 CS in the control group wich consisted also of 15 triplets. The corrected mortality rate in the study group was lower than in the control group (2.6% vs 7.1%) but did not reach statistical significance. Apgar scores at 1 and 5 minutes were significantly higher in the study group (P < 0.002). Apgar scores for the third triplet were also higher in the study group (P < 0.05). In comparing the combined mortality and morbidity between the study group and the control group, no difference was found in the first triplet, but those of the second and third triplets were significantly lower in the study group. Of interest is the finding that the combined mortality and morbidity was not different statistically among the first, second, and third triplets in the study group, while in the control group an increase from the first to the third triplet was noted (21%, 31%, and 43%, respectively). A more liberal approach toward abdominal delivery of pregnancies of higher fetal number is advocated.
Thèses sur le sujet "Tripletti"
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RONCHI, ALESSANDRA. « Hybrid and Nanostructured materials for low power photon upconversion based on triplet-triplet annihilation ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/370864.
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Durante il dottorato ho investigato il processo fotofisico di "upconversion" assistito da annichilazione tripletto-tripletto (TTA-UC) tramite studi di spettroscopia in sistemi profondamente differenti gli uni dagli altri. In TTA-UC radiazione ad alta energia è emessa dalla ricombinazione radiativa dello stato di singoletto eccitato di una molecola emettitore, popolato precedentemente dall'annichilazione dei tripletti di due emettitori. Un sensibilizzatore immagazzina la luce incidente a bassa energia e trasferisce l'eccitazione agli emettitori tramite trasferimento di energia alla Dexter. Poiché il suo funzionamento si basa su tripletti mestastabili, TTA-UC può essere altamente efficiente anche in condizioni di luce non coerente e a bassa energia. Come tale, è particolarmente adatto per dispositivi che sfruttano l'energia solare poiché è in grado di aumentarne l'efficienza di conversione limitando le perdite per trasmissione. Mi sono concentrata su due problemi importanti che tuttora limitano l'impiego di materiali che attuano TTA-UC (upconverters), ossia la limitata capacità di immagazzinare energia dei comuni sensibilizzatori organici e le scarse prestazioni di TTA-UC in upconverters a stato solido, i quali sono più adatti per applicazioni tecnologiche rispetto a sistemi liquidi. Per risolvere il primo problema ho investigato sensibilizzatori ibridi, composti da nanostrutture a semiconduttore decorate con molecole organiche, con ampio assorbimento. Nanocristalli di CdSe drogati con cationi d'oro e decorati con acido antracenico carbossilico si sono dimostrati essere sensibilizzatori ibridi efficienti ed innovativi. Il drogante introduce nel gap energetico dei nanocristalli livelli localizzati su cui le lacune si localizzano sulla scala dei picosecondi, più velocemente dell'estrazione di lacune sul livello HOMO dei leganti. Con tale strategia ho raggiunto l'efficienza di UC del 12%, record per sistemi ibridi. Ho poi mostrato come le proprietà superficiali e fotofisiche di nanoplatelets di CdSe le rendano ottimali candidati in sensibilizzatori ibridi. Ho mostrato che il ricoprimento delle superfici non è omogeneo, ma procede ad isole e l'interazione di "π- π stacking" porta alla formazione di aggregati sulle superfici delle nanoplatelets, con il risultato di ridurre l'energia dei tripletti dei leganti con profonde ripercussioni sulle prestazioni di TTA-UC e sulla scelta della specie emettitrice. Riguardo al secondo problema, ho studiato due upconverters a stato solido, polimeri vetrosi nanostrutturati che mostrano proprietà macroscopiche simili ma realizzati con tecniche differenti. Essi presentano domini liquidi di dimensione inferiore a 50 nm dove le specie che attuano TTA-UC si accumulano, racchiuse in una matrice rigida polimerica che fornisce protezione da ossigeno e qualità ottica eccellenti e stabilità a lungo termine. Il confinamento molecolare permette di aumentare la densità locale di eccitoni aumentando l'efficienza di UC a basse potenze grazie alle ridotte distanze intermolecolari e all'attivazione del regime di TTA-UC confinato.Ho inoltre studiato un nuovo emettitore derivato da perilene, realizzato con lo scopo di aumentarne l'efficienza di fluorescenza. Grazie a questo emettitore ho raggiunto l'efficienza record di UC di 42%, dovuta proprio alla struttura molecolare dell'emettitore che permette di limitare la formazione di aggregati, garantendo un'eccellente efficienza di generazione di singoletti tramite TTA. Infine, ho presentato una prospettiva riguardo alle prestazioni che possono essere raggiunte combinando le due tematiche trattate, ossia inserendo sensibilizzatori ad ampio assorbimento in polimeri nanostrutturati. Trovando il giusto compromesso tra taglia dei domini liquidi e distribuzione dell'energia di eccitazione si raggiungerebbe la massima efficienza di UC a potenze minori dell'irradianza solare, promuovendo lo sviluppo di upconverters a stato solido per tecnologie a energia solareIn my PhD project, I investigated the photophysical process of photon upconversion assisted by triplet-triplet annihilation (sTTA-UC) through spectroscopy studies in a variety of systems, profoundly different on many levels. In sTTA-UC high energy radiation is emitted from the fluorescent recombination of the excited singlet of an emitter molecule, previously populated via annihilation of the metastable triplet states of two emitters. This is a sensitized process since a sensitizer is necessary to harvest the low energy incident light and to transfer the stored energy to the emitters via Dexter energy transfer. Because its functioning relies on long-lived metastable triplets, this process can be highly efficient also under low power, noncoherent light. As such, sTTA-UC is particularly suited for solar applications as it can increase the conversion efficiency by reducing transmission losses. During my studies, I focused on addressing two crucial issues that still limit the application of upconverters in solar technologies, i.e. the limited storage ability of common organic sensitizers and the poor sTTA-UC performance in solid-state upconverters, which are intrinsically better suited than liquid solutions for technological applications. To solve the first problem, I investigated hybrid sensitizers, composed of semiconductor nanostructures decorated with conjugated organic ligands characterized by broadband absorption. CdSe nanocrystals (NCs) doped with gold cations and decorated with 9-anthracene carboxylic acid demonstrated to be efficient innovative broadband hybrid sensitizers. The doping strategy inserts into the NCs energy gap localized hole-accepting states where the holes localize on the picosecond timescale, outpacing hole transfer to the ligand HOMO. With this strategy, I achieved the UC efficiency of 12%, the record performance obtained so far for hybrid upconverters. I then discussed how the CdSe nanoplatelets surface and photophysical properties make them potential optimal light harvesters. My studies on the nanoplatelets-to-ligands energy transfer dependency on the surface ligand density revealed that the surface coverage is not homogeneous but proceeds in an island-like way promoted by π- π stacking and results in the formation of ligands aggregates on the nanoplatelets surfaces, which causes a redshift of the ligand triplet energy with critical repercussions on the sTTA-UC performance and on the emitter selection. To address the second issue, I investigated two solid-state upconverters, i.e. nanostructured glassy polymers that show similar macroscopic properties but fabricated via different approaches. They both feature liquid droplets of mean size less than 50 nm where the upconverting dyes accumulate, embedded in a rigid polymer matrix that grants excellent oxygen protection and optical quality and long-term stability. The dyes confinement allows to increase the effective local excitons density resulting in an enhanced UC efficiency at low excitation intensities, thanks to the reduced intermolecular distances and the activation of the confined sTTA-UC regime. I also introduced a new perylene derivative as emitter, specifically designed to prevent molecular aggregation to maximize its fluorescence efficiency. By employing this emitter, I achieved the record UC efficiency of 42%, which directly stems from the emitter molecular structure, as it limits the formation of aggregates, while guaranteeing excellent singlet generation efficiency upon TTA. I finally presented a perspective of the performances that can be achieved by combining the two topics considered, i.e. loading broadband sensitizers in nanostructured polymers. I highlighted that if the best trade-off between nanostructure size and energy distribution is met the maximum UC efficiency can be achieved at excitation powers orders of magnitude lower that the solar irradiance, therefore promoting the development of real-world solid-state upconverters.
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Ferreira, Giovana Chimello. « \"Fotopolimerização iniciada por tioxantona e outros indicadores - Estudos fundamentais e aplicações\" ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-29012007-112944/.
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A cinética de fotopolimerização do monômero metacrilato de metila (MMA) foi investigada usando o fotoiniciador tioxantona (TX) e o co-iniciador trietilamina (TEA), a fim de elucidar o mecanismo de fotopolimerização. A dilatometria foi usada como técnica para a determinação das cinéticas de polimerização. Determinaram-se os rendimentos quânticos de polimerização. Os estados excitados foram estudados por fluorescência estática para determinar as constantes de supressão de fluorescência pela amina e pelo monômero. Medidas de fotólise por pulso de laser permitiram obter o espectro de absorção triplete-triplete da tioxantona, bem como a constante de supressão do estado triplete. Os resultados mostraram que a supressão ocorre por um processo colisional no estado singlete e que os radicais eficientes na fotoiniciação são originados da amina TEA. A massa molecular média dos polímeros obtidos foi determinada por medidas de cromatografia de permeação em gel (GPC). Em uma segunda etapa, foi investigada a polimerização fotoiniciada por fotoiniciadores usados em resinas dentárias, canforquinona (CQ), 1,2-fenilpropanodiona (PPD), Lucirin e Irgacure. A velocidade de polimerização foi acompanhada por dilatometria usando excitação acima de 348 nm. Obteve-se os rendimentos quânticos de polimerização e os polímeros foram caracterizados por GPC. A maior constante de velocidade de polimerização obtida foi para o Irgacure e o maior rendimento quântico de polimerização obtido foi para o Lucirin. As diferenças na eficiência da polimerização são atribuídas à formação de radicais e à capacidade de gerar radicais a partir da absorção da luz incidente. Por fim, investigou-se os espectros de absorção triplete-triplete (TTA) da TX em diferentes solventes usando a técnica de fotólise por pulso de laser. Observou-se a formação de três bandas, duas referentes ao triplete da TX (uma em 300 nm e outra em 600 nm) e em 400 nm, observou-se a formação do radical cetila da TX. A abstração de hidrogênio do solvente pela TX pode ocorrer em 340 nm em solventes com constante de abstração de hidrogênio (kabstr) alto. Esse fator pode ser observado nos solventes 2-propanol e etanol. O substituinte na TX mostrou, através do parâmetro de Hammett do substituinte que com o aumento da eletronegatividade há um deslocamento do máximo de absorção do transiente para comprimentos de onda menores.The photopolymerization of the monomer methyl methacrylate (MMA) using thioxanthone (TX) as photoinitiator and triethylamine (TEA) as co-initiator, was investigated in order to explain the photopolymerization mechanism. Dilatometry was used to determine the kinetics of polymerization. The polymerization quantum yields were determined. The excited states were studied using static fluorescence in order to determine the fluorescence rate quenching by the amine and the monomer. The triplet-triplet absorption (TTA) spectrum of thioxanthone and the rate constant of quenching of the triplet state were obtained using flash photolysis technique. The results showed that the singlet state quenching occurs by a colisional process and the efficient radicals in the photoinitiation process are originated from the amine TEA. The molar mass of the obtained polymers was determined by gel permeation chromatography (GPC). The polymerization photoinitiated by the photoinitiators used in dental resins, Camphorquinone (CQ), 1,2- Phenylpropanodione (PPD), Lucirine and Irgacure was investigated in a second step. The rate of polymerization was studied by dilatometry with excitation above 348 nm. The polymerization quantum yields were obtained and the polymers were characterized by GPC. The larger rate constant of polymerization was found for Irgacure and the larger polymerization quantum yield was obtained for Lucirine. The differences in polymerization efficiencies can be tracked to the formation of radicals and the capability to produce the radicals after incident light absorption. Finally, the TTA of TX was studied in different solvents using the flash photolysis technique. The spectrum presented three bands, two due to the transient of TX (at 300 and 600 nm), and one at 400 nm assigned to the cetyl radical. The abstraction of a solvent hydrogen by TX is observed at 340 nm in solvents with high hydrogen abstraction constant (kabstr). This fact can be observed in 2-propanol and ethanol. An increase in the solvent polarity stabilizes the electronic pp* states and unstabilizes the np* states. The substitution in the TX molecule produced a shift to lower wavelength in the maximum absorption of transient with the increase of the electronegativity, as indicated by the dependence of the Hammett parameter.
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Reineke, Sebastian. « Controlling Excitons : Concepts for Phosphorescent Organic LEDs at High Brightness ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-39520.
Texte intégralRésumé :
This work focusses on the high brightness performance of phosphorescent organic light-emitting diodes (OLEDs). The use of phosphorescent emitter molecules in OLEDs is essential to realize internal electron-photon conversion efficiencies of 100 %. However, due to their molecular nature, the excited triplet states have orders of magnitude longer time constants compared to their fluorescent counterparts which, in turn, strongly increases the probability of bimolecular annihilation. As a consequence, the efficiencies of phosphorescent OLEDs decline at high brightness – an effect known as efficiency roll-off, for which it has been shown to be dominated by triplet-triplet annihilation (TTA). In this work, TTA of the archetype phosphorescent emitter Ir(ppy)3 is investi- gated in time-resolved photoluminescence experiments. For the widely used mixed system CBP:Ir(ppy)3, host-guest TTA – an additional unwanted TTA channel – is experimentally observed at high excitation levels. By using matrix materials with higher triplet energies, this effect is efficiently suppressed, however further studies show that the efficiency roll-off of Ir(ppy)3 is much more pronounced than predicted by a model based on Förster-type energy transfer, which marks the intrinsic limit for TTA. These results suggest that the emitter molecules show a strong tendency to form aggregates in the mixed film as the origin for enhanced TTA. Transmission electron microscopy images of Ir(ppy)3 doped mixed films give direct proof of emitter aggregates. Based on these results, two concepts are developed that improve the high brightness performance of OLEDs. In a first approach, thin intrinsic matrix interlayers are incorporated in the emission layer leading to a one-dimensional exciton confinement that suppresses exciton migration and, consequently, TTA. The second concept reduces the efficiency roll-off by using an emitter molecule with slightly differ- ent chemical structure, i.e. Ir(ppy)2(acac). Compared to Ir(ppy)3, this emitter has a much smaller ground state dipole moment, suggesting that the improved performance is a result of weaker aggregation in the mixed film. The knowledge gained in the investigation of triplet-triplet annihilation is further used to develop a novel emission layer design for white organic LEDs. It comprises three phosphorescent emitters for blue, green, and red emission embedded in a multilayer architecture. The key feature of this concept is the matrix material used for the blue emitter FIrpic: Its triplet energy is in resonance with the FIrpic excited state energy which enables low operating voltages and high power efficiencies by reducing thermal relaxation. In order to further increase the device efficiency, the OLED architecture is optically optimized using high refractive index substrates and thick electron transport layers. These devices reach efficiencies which are on par with fluorescent tubes – the current efficiency benchmark for light sourcesDiese Arbeit richtet ihren Fokus auf die Untersuchung der Leistungsfähigkeit von phosphoreszenten, Licht-emittierenden organischen Dioden (OLEDs) im Bereich hoher Betriebshelligkeiten. Phosphoreszente Emittermoleku ̈le werden in OLEDs eingesetzt, um interne Elektron-Photon Konversionseffizienzen von 100% zu erreichen. Begründet in ihrer chemischen Struktur, weisen die angeregten Triplett-Zustände dieser Emitter um Größenordnungen längere Zeitkonstanten als die Emission fluo- reszenter Materialien auf, sodass die Wahrscheinlichkeit bimolekularer Auslöschung stark ansteigt. Dies resultiert in einem deutlichen Effizienzrückgang phosphoreszenter OLEDs bei großen Leuchtdichten. Dieser als Roll-off bekannter Effekt wird bei hohen Anregungsdichten hauptsächlich durch Triplett-Triplett Annihilation (TTA) bestimmt. In der Arbeit wird TTA an einem Modellmolekül, dem phosphoreszenten Emit- ter Ir(ppy)3, in zeitaufgelösten Photolumineszenz Experimenten untersucht. Für das bekannte Emittersystem CBP:Ir(ppy)3 wird bei hohen Anregungsdichten Host-Guest TTA beobachtet, was einen zusätzlichen, ungewünschten TTA Kanal darstellt. Dieser Effekt wird durch das Verwenden von Matrix Materialien mit höherer Triplett Energie vermieden, jedoch zeigt sich in weiteren Untersuchungen, dass der Roll-off deutlich stärker ist als von einem auf Förster Energieübertrag basierendem Modell vorhergesagt, welches selbst ein intrinsisches Limit für TTA in phosphoreszenten Systemen beschreibt. Die Diskrepanz zwischen experimenteller Beobachtung und Modellvorhersage wird durch eine starke Tendenz des Emitters, Aggregate zu bilden, erklärt, was TTA deutlich verstärkt. Diese Aggregate werden mit Hilfe von Transmissionselektronenmikroskopie an Ir(ppy)3-dotierten Mischsystemen direkt nachgewiesen. Basierend auf diesen Resultaten werden zwei Konzepte entwickelt, um die Effizienz phosphoreszenter Systeme bei hohen Helligkeiten zu verbessern. Im ersten Ansatz werden dünne intrinsische Schichten des Matrixmaterials in die Emissionsschicht eingebaut, was die Exzitonenbewegung in einer Raumrichtung und damit auch TTA stark unterdrückt. Das zweite Konzept reduziert den Effizienz Roll-off durch die Verwendung eines phosphoreszenten Emitters Ir(ppy)2(acac) mit einer leicht abgeänderten Molekularstruktur. Im Vergleich mit Ir(ppy)3 weist dieser ein deutlich kleineres Dipolmoment im molekularen Grundzustand auf, wodurch die Aggregation vermindert wird. Aufbauend auf den Ergebnissen der TTA wird ein neuartiges Emissionsschicht-Design für weißes Licht entwickelt. In diesem Konzept werden drei phosphoreszente Materialien für blaue, grüne und rote Farbe in eine Vielschicht-Architektur eingebracht. Das Hauptmerkmal der Emissionsschicht ist die Wahl des Matrix-Materials für dem blauen Emitter FIrpic: Seine Triplett Energie liegt resonant zu dem FIrpic Triplett Zustand, wodurch niedrige Betriebsspannungen und hohe Leistungseffizienzen ermöglicht werden, da die thermische Relaxierung reduziert wird. Um die Ef- fizienz dieser weißen OLEDs weiter zu erhöhen, wird die entwickelte OLED Architektur zusätzlich durch die Verwendung von hochbrechenden Substraten und dicken Elektronen-Transportschichten optisch optimiert. Bei beleuchtungsrelevanten Helligkeiten erreichen diese OLEDs das Effizienzniveau von Leuchtstoffröhren – letztere stellen heute den Effizienz-Maßstab dar
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Piper, Roland. « Bimolecular triplet-triplet annihilation upconversion for photovoltaics ». Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24858.
Texte intégralRésumé :
Organic upconversion of photons through triplet energy exchange between two or more molecules (OUC) has been investigated through transient absorption and fluorescence spectroscopy, kinetic rate modelling and morphological analysis of thin films. An OUC system, consisting of one sensitising molecule (PQ4Pd) and an emitting molecule (rubrene), was first studied to explore the possibility of modelling the entire OUC process with a kinetic rate model. Transient absorption spectroscopy allowed for the intermediate steps of OUC to be directly observed and fitted, producing rate constants for each step in the process. This complete model was then optimised against fluorescence measurements from a system containing PtTPBP (sensitiser) and perylene (emitter) to calculate rate constants for that system from a single fluorescence type experiment, as opposed to several orthogonal Stern-Volmer type experiments. The possibility of fabricating a thin film OUC has been investigated through microscopy, fluorescence spectroscopy and a simple Monte-Carlo model. Using a system of PtOEP (sensitiser) and DPA (emitter), it was shown that the maximal efficiency of a thin film containing these molecules suspended in a PMMA matrix is found when the matrix is between 80 and 85 weight% of the total mixture. It was shown that on short timescales (a few seconds to a few minutes), atmospheric oxygen does not adversely affect thin film upconverters of this type as local oxygen is extremely rapidly quenched (less than a ms) and fresh oxygen is not able to diffuse back into the matrix at a rate that is competitive to OUC. It was shown that the degree of intermixing of active materials is of absolute importance in this fabrication, and a novel optical technique for measuring this intermixing in air was developed, some preliminary results are included.
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Deng, Fan. « Photon Upconversion Based on Triplet-Triplet Annihilation ». Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1395249331.
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Wilke, Bryn. « UPCONVERTING LOW POWER PHOTONS THROUGH TRIPLET-TRIPLET ANNIHILATION ». Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1335378364.
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Alazemi, Abdulrahman. « Investigation of Factors in Triplet-Triplet Annihilation Upconversion ». University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1521189118425574.
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Cao, Xian. « Investigation of Photochemical Upconversion Based on Triplet-Triplet Annihilation ». University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1455209554.
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Ruß, Carsten. « From Triplet Correlations to Triplet Interactions in Colloidal Suspensions ». [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-36883.
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Hope, Adam John. « Fluorinated emitter molecules for triplet-triplet annihilation up-conversion media ». Thesis, Durham University, 2014. http://etheses.dur.ac.uk/10623/.
Texte intégralRésumé :
This thesis details the synthesis, characterisation and photophysical properties of various fluorinated emitters for triplet-triplet annhilation up-conversion systems. The theory and mechanism of TTAUC is evaluated and the molecular design of the annihilating emitter molecule reviewed to allow improvement of the external up-conversion quantum yield and overall energy efficiency of the process. Three main series of chromaphores were investigated, based on diphenylanthracenes, bisphenylperylenes, and 3,5,8-triphenylBODIPYs. These were synthesised by metal catalysed aryl-aryl coupling (Suzuki-Miyaura) or nucleophilic substitution reactions and, when paired with appropriate sensitizing molecules, allowed the up-conversion of green to blue; red to green; and near IR/red to orange respectively. The effect of increasing fluorination on the ease of synthesis and photophysical properties of these emitter systems was studied with a view to their application in up-conversion systems. Fluorinated emitter molecules were shown to be highly resistant to degradation by UV light compared to their non-fluorinated analogues. The up-conversion ability of these systems was evaluated and novel fluorinated BODIPY based dyes were produced that have high fluorescence quantum yields of over 90%. Finally the up-conversion of up-converting nanoparticles incorporating fluorinated emitters was evaluated.
Livres sur le sujet "Tripletti"
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Triplets. New York : F. Watts, 1988.
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ill, Roche Christine, dir. Triplets. New York, N.Y., U.S.A : Viking, 1991.
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Yektai, Niki. Triplets ! Brookfield, Conn : Millbrook Press, 1998.
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Triplet. London : Arrow Books, 1988.
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Zahn, Timothy. Triplet. New York, N.Y : Baen Books, 1987.
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Stewart, Pat. Parenting triplets. Coogee, NSW : Australian Multiple Birth Association, 1995.
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Copyright Paperback Collection (Library of Congress), dir. Triplet code. New York : Berkley Prime Crime, 2001.
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Diamond, Jacqueline. The holiday triplets. Toronto : Harlequin, 2010.
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Roser, Capdevila i. Valls, dir. Meet the triplets. New York : Derrydale Books, 1986.
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Gore, N. T. Triplet Pregnancy & Your First Year with Triplets. CreateSpace Independent Publishing Platform, 2014.
Trouver le texte intégralChapitres de livres sur le sujet "Tripletti"
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Backman, Brian. « Triplets ». Dans Thinking in Threes, 12. New York : Routledge, 2021. http://dx.doi.org/10.4324/9781003239048-3.
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Weik, Martin H. « triplet ». Dans Computer Science and Communications Dictionary, 1838. Boston, MA : Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_20150.
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Mahmood, Zafar, Shaomin Ji, Jianzhang Zhao, Mushraf Hussain, Farhan Sadiq, Noreen Rehmat et Muhammad Imran. « Organic Triplet Photosensitizers for Triplet-Triplet Annihilation Upconversion ». Dans Emerging Strategies to Reduce Transmission and Thermalization Losses in Solar Cells, 71–105. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70358-5_5.
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Gray, Victor. « Photon upconversion through triplet–triplet annihilation ». Dans Photochemistry, 404–20. Cambridge : Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788016520-00404.
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Shekhar, Shashi, et Hui Xiong. « Image Triplet ». Dans Encyclopedia of GIS, 480. Boston, MA : Springer US, 2008. http://dx.doi.org/10.1007/978-0-387-35973-1_589.
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Tomioka, Hideo. « Triplet Carbenes ». Dans Reactive Intermediate Chemistry, 375–461. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2005. http://dx.doi.org/10.1002/0471721492.ch9.
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English, Neil. « Triplet Apos ». Dans Patrick Moore's Practical Astronomy Series, 143–65. New York, NY : Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-6403-8_10.
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Jansson, Jesper, Andrzej Lingas et Eva-Marta Lundell. « The Approximability of Maximum Rooted Triplets Consistency with Fan Triplets and Forbidden Triplets ». Dans Combinatorial Pattern Matching, 272–83. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-19929-0_23.
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Romano, Antonio. « Doublets and Triplets ». Dans Geometric Optics, 145–55. Boston : Birkhäuser Boston, 2009. http://dx.doi.org/10.1007/978-0-8176-4872-5_7.
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Romano, Antonio, et Roberto Cavaliere. « Doublets and Triplets ». Dans Geometric Optics, 163–73. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43732-3_8.
Texte intégralActes de conférences sur le sujet "Tripletti"
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Perrot, Michael, et Ulrike von Luxburg. « Boosting for Comparison-Based Learning ». Dans Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California : International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/255.
Texte intégralRésumé :
We consider the problem of classification in a comparison-based setting: given a set of objects, we only have access to triplet comparisons of the form ``object A is closer to object B than to object C.'' In this paper we introduce TripletBoost, a new method that can learn a classifier just from such triplet comparisons. The main idea is to aggregate the triplets information into weak classifiers, which can subsequently be boosted to a strong classifier. Our method has two main advantages: (i) it is applicable to data from any metric space, and (ii) it can deal with large scale problems using only passively obtained and noisy triplets. We derive theoretical generalization guarantees and a lower bound on the number of necessary triplets, and we empirically show that our method is both competitive with state of the art approaches and resistant to noise.
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Kumari, Priyadarshini, Ritesh Goru, Siddhartha Chaudhuri et Subhasis Chaudhuri. « Batch Decorrelation for Active Metric Learning ». Dans Twenty-Ninth International Joint Conference on Artificial Intelligence and Seventeenth Pacific Rim International Conference on Artificial Intelligence {IJCAI-PRICAI-20}. California : International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/ijcai.2020/312.
Texte intégralRésumé :
We present an active learning strategy for training parametric models of distance metrics, given triplet-based similarity assessments: object $x_i$ is more similar to object $x_j$ than to $x_k$. In contrast to prior work on class-based learning, where the fundamental goal is classification and any implicit or explicit metric is binary, we focus on perceptual metrics that express the degree of (dis)similarity between objects. We find that standard active learning approaches degrade when annotations are requested for batches of triplets at a time: our studies suggest that correlation among triplets is responsible. In this work, we propose a novel method to decorrelate batches of triplets, that jointly balances informativeness and diversity while decoupling the choice of heuristic for each criterion. Experiments indicate our method is general, adaptable, and outperforms the state-of-the-art.
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Bullimore, Mark A., David B. Elliot et Ian L. Bailey. « Improving the Reliability of the Pelli-Robson Contrast Sensitivity Test ». Dans Noninvasive Assessment of the Visual System. Washington, D.C. : Optica Publishing Group, 1991. http://dx.doi.org/10.1364/navs.1991.md12.
Texte intégralRésumé :
The clinical applications of contrast sensitivity testing have been discussed in numerous reports, and a number of printed contrast sensitivity tests are commercially available. Some of these tests use letters as targets rather than sine or square wave gratings (Regan and Neima, 1983; Pelli et al., 1988). Letter contrast sensitivity charts have the advantage of being quick to administer and the nature of the task is familiar to both the patient and the practitioner. The letter identification task has the advantage of being a multiple-alternative forced-choice procedure that limits patient criterion effects (Vaegen and Halliday, 1983). The Pelli-Robson chart (Pelli et al., 1988) consists of sixteen triplets of letters, with each letter subtending 3 degrees at the recommended viewing distance of 1 meter. Within each triplet the letters have the same contrast and the contrast in each successive triplet decreases by a factor of 0.15 log units (√2). Pelli et al. recommend scoring contrast sensitivity as the lowest contrast level at which at least two of the triplet are identified correctly.
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Enayat, S. M., F. G. H. Hill, Y. Sultan et C. W. Williams. « STUDY OF IIA VON WILLEBRAND'S DISEASE (VWD) VARIANTS TO DETERMINE DEGREE AND TYPES OF HETEROGENEITY ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644102.
Texte intégralRésumé :
Thirty four IIA vWD patients (16 from kindred I, 2 from kindred II and 17 unrelated patients) from 19 families were studied to compare multimer patterns using discontinuous SDS gel electrophoresis on a variety of agarose gels. Platelet multi-mers and effect of EDTA on plasma multimers were also studied in some.The large kindred and 9 other patients showed identical multimer and triplet abnormalities. The 11 other patients showed different multimer patterns either by having intermediate multimers or different triplet patterns. The second kindred had a similar triplet abnormality to kindred I but had intermediate multimers. Two other patients showed similar patterns except on 2% agarose gels when differences in the lowest multimer was seen. Of the 3 patients of YS, one showed the common IIA pattern but also had intermediate multimers, another had an unusually faint upper triplet band, while the third in addition to a faint upper triplet band with ESVWF 2+ had no identification of minor or major bands with ESVWF 10+ Another patient lacked high and some intermediate multimers but had a normal triplet pattern. The pattern we have seen in Kernoff's patient (1) still appears unique. In kindred II abnormal triplets persisted and high multimers appeared in EDTA plasma. In kindred I (and similar patients) intermediate multimers and a change in triplet pattern was observed in EDTA while lysed platelets showed an abnormal pattern different to the plasma one.This emphasizes the heterogeneity of IIA vWD and the need to consider multimer deletion, triplet pattern, platelet multimers, effect of EDTA in trying to subclassify in order to study structure function relationships of vWF.1. Kernoff PBA, Gruson R, Rizza CR. (1974) A variant of factor VIII related antigen. Br. J. Haematol. 26: 435.+ESVWF 2 and 10 are monoclonal antibodies to vWF epitopes.
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Gorbova, E. V. « ASPECTUAL TRIPLETS OF THE RUSSIAN VERB IN DIACHRONY : EVIDENCE FROM THE RUSSIAN NATIONAL CORPUS ». Dans International Conference on Computational Linguistics and Intellectual Technologies "Dialogue". Russian State University for the Humanities, 2020. http://dx.doi.org/10.28995/2075-7182-2020-19-321-347.
Texte intégralRésumé :
The paper deals with the so-called aspectual triplets of the Russian verb. Based on the data from the Russian National Corpus, it proposes a diachronic method to study triplets as well as a two-component model of the Russian aspect as an alternative to the traditional word-based classification model. The first component of the model is a morphological mechanism of the imperfectivizing suffixation of prefixed verbs that is inflectional (ras-kry-t’PFV — ras-kryva-t’IPFV2 ‘disclose, reveal’), but has a limited scope of action (prefixed verbs only). The second component of the model is the actionality (lexical aspect) with a maximal scope. Related to the verb class as a whole, it is especially crucial for non-prefixed simplexes. Actionality enables the functioning and perfective / imperfective characterization of simplexes which do not fall under the inflectional grammatical aspect. The analysis of ten biimperfective triplets resulted in several observations and conclusions. One of them concerns the role of a ‘joker’, which all imperfective simplexes (IPFV1) have in the aspectual triplets as (quasi)synonyms for corresponding secondary imperfectives (IPFV2). A working hypothesis on the predominance of IPFV1 over PFV in every triplet, based on the broader polysemy of the former, has not been confirmed. However, the two-component model has explanatory power for the cases of reverse frequency (PFV over IPFV1) through its lexical aspect component. Another working hypothesis on a possible increase or a decrease in the number of secondary imperfectives in diachrony was partially confirmed — an increase was noted for the 20/21st century.
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Ilieş, Horea T., et Vadim Shapiro. « A Class of Forms From Function : The Case of Parts Moving in Contact ». Dans ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/dtm-21704.
Texte intégralRésumé :
Abstract We consider the general problem of designing mechanical parts moving in contact under the influence of externally applied loads. Geometrically, the problem may be characterized in terms of a conjugate triplet which is formed by the two shapes moving in contact and their relative motion. We show that every such triplet belongs to at least two classes of functionally equivalent designs that may be represented uniquely by maximal triplets, corresponding respectively to the two largest contact shapes that are guaranteed to contain all other possible solutions to the contact design problem. In practical terms, the proposed characterization of the contact problem enables the systematic exploration of the design space using fully defined representatives of the functionally equivalent class of parts. Furthermore, such exploration may be performed using standard tools from geometric modeling, and without assuming any particular parametrization that necessarily restrict both the design space and possible computational techniques for exploring feasible designs. Because it supports generation of an essentially unlimited space of design solutions for a given contact problem, the proposed approach is particularly effective at the conceptual design stage.
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Polak, Daniel, Harriet Coulthard, Rahul Jayaprakash, Kealan Fallon, Anastasia Leventis, Hugo Bronstein, John Anthony, David G. Lidzey, Jenny Clark et Andrew Musser. « A tale of two triplets : manipulating and harvesting triplet pairs with strong light-matter coupling (Conference Presentation) ». Dans Physical Chemistry of Semiconductor Materials and Interfaces XVII, sous la direction de Hugo A. Bronstein et Felix Deschler. SPIE, 2018. http://dx.doi.org/10.1117/12.2321172.
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Ye, Rui, Xin Li, Yujie Fang, Hongyu Zang et Mingzhong Wang. « A Vectorized Relational Graph Convolutional Network for Multi-Relational Network Alignment ». Dans Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California : International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/574.
Texte intégralRésumé :
Alignment of multiple multi-relational networks, such as knowledge graphs, is vital for AI applications. Different from the conventional alignment models, we apply the graph convolutional network (GCN) to achieve more robust network embedding for the alignment task. In comparison with existing GCNs which cannot fully utilize multi-relation information, we propose a vectorized relational graph convolutional network (VR-GCN) to learn the embeddings of both graph entities and relations simultaneously for multi-relational networks. The role discrimination and translation property of knowledge graphs are adopted in the convolutional process. Thereafter, AVR-GCN, the alignment framework based on VR-GCN, is developed for multi-relational network alignment tasks. Anchors are used to supervise the objective function which aims at minimizing the distances between anchors, and to generate new cross-network triplets to build a bridge between different knowledge graphs at the level of triplet to improve the performance of alignment. Experiments on real-world datasets show that the proposed solutions outperform the state-of-the-art methods in terms of network embedding, entity alignment, and relation alignment.
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McLean, Daniel G., et Mark C. Brant. « Triplet-triplet nonlinear absorption dynamics in C60 ». Dans OE/LASE'93 : Optics, Electro-Optics, & Laser Applications in Science& Engineering, sous la direction de Bodil Braren et Mikhail N. Libenson. SPIE, 1993. http://dx.doi.org/10.1117/12.147613.
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Zhou, Haoyi, Jianxin Li, Jieqi Peng, Shuai Zhang et Shanghang Zhang. « Triplet Attention ». Dans KDD '21 : The 27th ACM SIGKDD Conference on Knowledge Discovery and Data Mining. New York, NY, USA : ACM, 2021. http://dx.doi.org/10.1145/3447548.3467241.
Texte intégralRapports d'organisations sur le sujet "Tripletti"
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Saillant, Eric, Jason Lemus et James Franks. Culture of Lobotes surinamensis (Tripletail). Mississippi Department of Marine Resources, janvier 2014. http://dx.doi.org/10.18785/ose.001.
Texte intégralRésumé :
The Tripletail, Lobotes surinamensis, is a pelagic fish found in tropical and sub-tropical waters of all oceans. Tripletails are often associated with floating debris and make frequent incursions in bays and estuaries where they are targeted by recreational fishermen. In Mississippi waters the species is typically present during the late spring and summer season that also correspond to the period of sexual maturation and spawning (Brown-Peterson and Franks 2001). Tripletail is appreciated as a gamefish but is also prized for its flesh of superior quality. The fast growth rate of juveniles in captivity documented by Franks et al. (2001) and the excellent quality of Tripletail flesh both contribute to the potential of this species for marine aquaculture. In addition, the production of cultured juveniles would be precious to develop a better understanding of the biology, early life history and habitat use of Tripletail larvae and juveniles, a topic largely undocumented to date, through experimental releases and controlled studies. The culture of tripletail thus supports the Tidelands Trust Fund Program through improved conservation of natural resources, potential enhancement of fisheries productivity and potential development of a new economic activity on the Gulf coast producing tripletail via aquaculture. The Objective of this project was to initiate development of methods and techniques needed to spawn captive held tripletail broodfish and raise their offspring to evaluate their growth and development in captivity. In this report we will present the results of studies aiming to develop methods and protocols for captive spawning of tripletail and the first data obtained on the early development of tripletail larvae. A major issue that was encountered with tripletail broodstock development during the project lied in the difficulties associated with identifying the sex of adults caught in the wild and candidates for being incorporated in mating sets for spawning. This issue was addressed during the course of the project by examining the potential of a non-lethal method of hormonal sexing. The results of these preliminary investigations are presented in the third part of this report. All protocols used in the project were determined with the guidance of the Institutional Animal Care and Use Committee (IACUC) of the University of Southern Mississippi (USM IACUC protocol number 10100108).
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Pavlopoulos, T. G. Triplet-Triplet Absorption and Polarization Spectra of Anthracene. Fort Belvoir, VA : Defense Technical Information Center, mai 1991. http://dx.doi.org/10.21236/ada235895.
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Iverson, R. GTF Triplet Optics. Office of Scientific and Technical Information (OSTI), janvier 2005. http://dx.doi.org/10.2172/839649.
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Welch, Kimo M. Contrived Vacuum Impedances in the Triplet Cryostat. Office of Scientific and Technical Information (OSTI), juillet 1995. http://dx.doi.org/10.2172/1119217.
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Pavlopoulos, Theodore G., et Daniel J. Golich. Triplet Extinction Coefficients of Some Laser Dyes II. Fort Belvoir, VA : Defense Technical Information Center, avril 1989. http://dx.doi.org/10.21236/ada207135.
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Partee, J., J. Shinar, S. W. Jessen, A. J. Epstein et W. Graupner. Intrinsically Trapped Triplet Excitons in pi-Conjugated Polymers. Fort Belvoir, VA : Defense Technical Information Center, septembre 1997. http://dx.doi.org/10.21236/ada330211.
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Peggs, S., et S. Tepikian. Roll Misalignments and Skew Errors of IR Triplet Quads. Office of Scientific and Technical Information (OSTI), septembre 1993. http://dx.doi.org/10.2172/1119407.
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Wei, J., et S. Peggs. Requested Systematic Body b5 Multipoles in RHIC Triplet Quadrupoles. Office of Scientific and Technical Information (OSTI), décembre 1993. http://dx.doi.org/10.2172/1119414.
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Pilat, F. Correction of the Triplet Skew Quadrupole Errors in RHIC. Office of Scientific and Technical Information (OSTI), mars 1995. http://dx.doi.org/10.2172/1119452.
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Castellano, Felix N. Programmable Triplet Formation and Decay in Metal-Organic Chromophores. Fort Belvoir, VA : Defense Technical Information Center, décembre 2011. http://dx.doi.org/10.21236/ada567091.
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