851 resultados para ent kaurane diterpene
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The biosynthetic origin of the dichloroimine functional group in the marine sponge terpene metabolites stylotellanes A ( 3) and B ( 4) was probed by the use of [C-14]-labelled precursor experiments. Incubation of the sponge Stylotella aurantium with [C-14]-labelled cyanide or thiocyanate resulted in radioactive terpenes in which the radiolabel was shown by hydrolytic chemical degradation to be associated specifically with the dichloroimine carbons. Additionally, label from both precursors was incorporated into farnesyl isothiocyanate ( 2). A time course experiment with [ 14C]cyanide revealed that the specific activity for farnesyl isothiocyanate decreases over time, but increases for stylotellane B ( 4), consistent with the rapid formation of farnesyl isothiocyanate ( 2) from inorganic precursors followed by a slower conversion to stylotellane B ( 4). The advanced precursors farnesyl isothiocyanate ( 2) and farnesyl isocyanide ( 5) were supplied to S. aurantium, and shown to be incorporated efficiently into stylotellane A ( 3) and B ( 4). Feeding of [C-14]-farnesyl isothiocyanate ( 2) resulted in a higher incorporation of label than with [C-14]-farnesyl isocyanide ( 5). Farnesyl isocyanide was incorporated into farnesyl isothiocyanate in agreement with labelling studies in other marine sponges. Both farnesyl isocyanide and isothiocyanate were further incorporated into axinyssamide A ( 11) as well as the cyclized dichloroimines (12)-(14), ( 16) that represent more advanced biosynthetic products of this pathway. These results identify the likely biosynthetic pathway leading to the major metabolites of S. aurantium.
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The absolute stereochemistry of amphilectene metabolites from Cribochalina sp. has been revised by a detailed NMR spectroscopic study of the Mosher ester derivatives of a related alcohol. The relative stereochemistry of the previously described amphilectenes has been reinvestigated and reassigned on the basis of the X-ray structural analysis carried out on one of them. The structure of a new amphilectene metabolite, which is an isothiocyanato analogue is also presented. (c) 2005 Elsevier Ltd. All rights reserved.
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Specific 3-azabicyclo[3.3.1]nonane derivatives undergo skeletal cleavage when subjected to light or Lewis acidic conditions affording novel heteratricycles, which is in stark contrast to 3-oxabicyclo[3.3.1]nonanes. (c) 2005 Elsevier Ltd. All rights reserved.
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We conducted a feasibility study to examine whether a paediatric patient at a regional hospital could be assessed by an ear, nose and throat (ENT) specialist via videoconference, therefore saving at least one journey to the tertiary hospital for a pre-admission appointment. A video-otoscope was used with standard videoconference equipment, and realtime images were transmitted at a bandwidth of 384 kbit/s. In all, 13 telepaediatric ENT clinics were conducted between November 2003 and April 2005, and 98 consultations were facilitated for 64 patients. The main reasons for referral were recurrent tonsillitis (25%) and obstructive sleep apnoea (23%). Of the 64 patients examined by telemedicine, 42 (66%) were recommended for surgery and placed on the surgical waiting list. About 12 patients (19%) required travel to the tertiary centre for further investigations and tests not available locally, while four patients (6%) were reviewed via videoconference during a scheduled clinic. Six patients (9%) required no further follow-up after their initial telepaedliatric consultation. Videoconferencing is an effective method of assessing ENT conditions of paediatric patients and for pre-screening potential surgical admissions to a tertiary hospital. Careful consideration of a number of economic and logistical factors needs to be made before large investments are made to expand the service.
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Existem muitas controvérsias sobre a real interferência da respiração no crescimento craniofacial. Este estudo avaliou a possível relação da influência do padrão respiratório com as variáveis cefalométricas: 1) variáveis esqueléticas sagitais: convexidade do ponto A, profundidade facial, profundidade da maxila e comprimento do corpo mandibular; 2) variáveis esqueléticas verticais: altura facial inferior, eixo facial, cone facial, plano palatal, plano mandibular, altura facial posterior e arco mandibular; 3) variáveis dentárias: protrusão do incisivo inferior e protrusão do incisivo superior. A amostra constituiu-se de 120 crianças do sexo masculino e do sexo feminino com más-oclusões dentárias de Classe I e II-1, respiradores bucais e nasais na fase da dentadura mista e permanente, com indicação para tratamento ortodôntico. Após as avaliações ortodôntica, otorrinolaringológica e fonoaudiológica a amostra foi dividida em 2 grupos: 60 crianças portadoras de más-oclusões Classe I e Classe II-1 respiradoras bucais e 60 crianças portadoras de más-oclusões Classe I e Classe II-1 respiradoras nasais, sendo cada grupo divididos em 3 subgrupos nas faixas etárias: 7 a 8 anos, 9 a 10 anos e 11 a 12 anos. Após a obtenção dos resultados e a interpretação da análise estatística, foi possível concluir que: 1) das relações entre os padrões respiratórios (bucal e nasal) e as variáveis esqueléticas sagitais: constatou-se que houve diferença estatisticamente significante, apresentando-se as variáveis cefalométricas: Convexidade pto. A: aumentada no grupo de respiração bucal, idade de 7 a 8 anos com má-oclusão Classe I. Profundidade facial : aumentada no grupo de respiração bucal, idade de 9 a 10 anos com má-oclusão Classe II-1. Profundidade maxila: aumentada no grupo de respiração bucal, idade de 9 a 10 anos com má-oclusão Classe II-1; 2) das relações entre os padrões respiratórios (bucal e nasal) e as variáveis esqueléticas verticais: constatou-se que houve diferença estatisticamente significante, apresentando-se as variáveis cefalométricas: Cone facial: diminuída no grupo de respiração bucal, idade 9 a 10 anos com má-oclusão Classe I. Arco mandibular : diminuída no grupo de respiração bucal, idade 7 a 8 anos com má-oclusão Classe II-1.; 3) das relações entre os padrões respiratórios (bucal e nasal) e as variáveis dentárias: constatou-se que não houve diferença estatisticamente significante para nenhuma das variáveis dentárias analisadas: protrusão do incisivo inferior e superior , não se relacionando com os padrões respiratórios (bucal e nasal).
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AIM To develop a short, enhanced functional ability Quality of Vision (faVIQ) instrument based on previous questionnaires employing comprehensive modern statistical techniques to ensure the use of an appropriate response scale, items and scoring of the visual related difficulties experienced by patients with visual impairment. METHODS Items in current quality-of-life questionnaires for the visually impaired were refined by a multi-professional group and visually impaired focus groups. The resulting 76 items were completed by 293 visually impaired patients with stable vision on two occasions separated by a month. The faVIQ scores of 75 patients with no ocular pathology were compared to 75 age and gender matched patients with visual im pairm ent. RESULTS Rasch analysis reduced the faVIQ items to 27. Correlation to standard visual metrics was moderate (r=0.32-0.46) and to the NEI-VFQ was 0.48. The faVIQ was able to clearly discriminate between age and gender matched populations with no ocular pathology and visual impairment with an index of 0.983 and 95% sensitivity and 95% specificity using a cut off of 29. CONCLUSION The faVIQ allows sensitive assessm ent of quality-of-life in the visually im paired and should support studies which evaluate the effectiveness of low vision rehabilitation services. © Copyright International Journal of Ophthalmology Press.
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In this paper we study some of the characteristics of the art painting image color semantics. We analyze the color features of differ- ent artists and art movements. The analysis includes exploration of hue, saturation and luminance. We also use quartile’s analysis to obtain the dis- tribution of the dispersion of defined groups of paintings and measure the degree of purity for these groups. A special software system “Art Paint- ing Image Color Semantics” (APICSS) for image analysis and retrieval was created. The obtained result can be used for automatic classification of art paintings in image retrieval systems, where the indexing is based on color characteristics.
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INTRODUCTION: Severe maternal morbidity , also known as maternal near miss , has been used as an alternative to the study of maternal mortality , since being more frequent shares the same determinants and enables the implementati on of epidem iological surveillance of cases . Since then, hospital audits ha ve been carried out to determine the rates of maternal near miss, its mai n causes and associated factors . More recently, population surveys based on self - reported morbidity have als o been presented as vi able in identifying these cases . OBJECTIVE: The aim of this study was to determine the prevalence and associated factors of maternal near miss and complications during pregnancy and puerperal period in Natal/RN. METHODS: A cross - secti onal population - based study was conducted in Natal /RN , Brazil, which has as its target population women aged 15 to 49 years who were pregnant in the last five years. It was carried out a probabilistic sam pling design based on a multi - stage complex sample , in which 60 census tracts were selected from three strata (north , south - east and west). Afterwards, domiciles were visited in order to obtain a sample of the 908 eligible women in whom a questionnaire was applied. The descriptive analyzes and bivariate ass ociations were performed using the Chi - square test and the estimate of the prevalence ratio (PR ) with 95% confidence interval (CI) and considering the weights and design effects . The Poisson regression analysis , also with 5% significance and 95% CI, was us ed for analyzes of associated factors. RESULTS: 848 women were identified and interviewed after visits in 8.227 households corresponding to a response rate of 93 . 4 %. The prevalence of maternal near miss was 41 . 1 /1 000NV, being the Intensive Care Unity stay i ng (19 . 1 /1 000 LB ) and eclampsia (13 . 5/1000LB) the most important marker s . The prevalence of complications in the puerperal peri od was 21 . 2 %, and hemorrhage (10 . 7%) and urinary tract infection (10 . 7%) the most frequently reported clinical conditions and rema in ing in the hospital for over a week after delivery the mo st frequent intervention (5.4%) . Regarding associated factors , the bivariate analysis showed an association between the increased number of complications in women of black/brown race ( PR= 1 . 23; CI95 % : 1 . 04 - 1 . 46) and lower socioeconomic status ( PR= 1 . 33; CI95%: 1 . 12 - 1 . 58) in women who had pre natal care in public service ( PR= 1 . 42; CI95%: 1 . 16 to 1 . 72 ) and that were not advised during prenatal about where they should do the d elivery (PR= 1 . 24; CI95%: 1 . 05 - 1 . 46), made the del ivery in the public service (PR= 1 . 63; CI95%: 1 . 30 - 2 . 03), had to search for more than one hospital for delivery (PR=1 . 22; CI95%: 1 . 03 - 1 . 45) and had no companion during childbirth ( PR =1 . 19; CI95%: 1 . 01 - 1 . 41) or at all times of childbirth c are - before, during and after childbirth - ( PR= 1 . 25, CI95%: 1 . 05 - 1 . 48) . Moreover, the number of days postpartum hospitalization was higher in women who had more complications (P R= 1 . 59 ; CI95%: 1 . 36 - 1 . 86). In the final regression model for both birth place (P R= 1 . 21 ; CI 95% : 1 . 02 to 1 . 44 ) and socioeconomic status (PR = 1.54 ; CI95%: 1 . 25 - 1 . 90 ) the association remained. CONCLUSION : Conducting population surveys using the pragmatic definition of near miss is feasible and may add importa nt information about this ev ent . It was possible to find the expression of health inequalities related to maternal health in the analysis of both socioeconomic conditions and on the utilization of health services.
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The soil heat flux and soil thermal diffusivity are important components of the surface energy balance, especially in ar id and semi-arid regions. The obj ective of this work was to carry out to estimate the soil heat flux from th e soil temperature measured at a single depth, based on the half-order time derivative met hod proposed by Wang and Bras (1999), and to establish a method capable of es timating the thermal diffusivity of the soil, based on the half order derivative, from the temporal series of soil temperature at two depths. The results obtained in the estimates of soil heat flux were compared with the values of soil heat flux measured through flux plates, and the thermal di ffusivity estimated was compared with the measurements carried out in situ. The results obtained showed excellent concordance between the estimated and measured soil heat flux, with correlation (r), coeffici ent of determination (R 2 ) and standard error (W/m 2 ) of: r = 0.99093, R 2 = 0.98194 and error = 2.56 (W/m 2 ) for estimated period of 10 days; r = 0,99069, R 2 = 0,98147 and error = 2.59 (W/m 2 ) for estimated period of 30 days; and r = 0,98974, R 2 = 0,97958 and error = 2.77 (W/m 2 ) for estimated period of 120 days. The values of thermal di ffusivity estimated by the proposed method showed to be coherent and consis tent with in situ measured va lues, and with the values found in the literature usi ng conventional methods.
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Software bug analysis is one of the most important activities in Software Quality. The rapid and correct implementation of the necessary repair influence both developers, who must leave the fully functioning software, and users, who need to perform their daily tasks. In this context, if there is an incorrect classification of bugs, there may be unwanted situations. One of the main factors to be assigned bugs in the act of its initial report is severity, which lives up to the urgency of correcting that problem. In this scenario, we identified in datasets with data extracted from five open source systems (Apache, Eclipse, Kernel, Mozilla and Open Office), that there is an irregular distribution of bugs with respect to existing severities, which is an early sign of misclassification. In the dataset analyzed, exists a rate of about 85% bugs being ranked with normal severity. Therefore, this classification rate can have a negative influence on software development context, where the misclassified bug can be allocated to a developer with little experience to solve it and thus the correction of the same may take longer, or even generate a incorrect implementation. Several studies in the literature have disregarded the normal bugs, working only with the portion of bugs considered severe or not severe initially. This work aimed to investigate this portion of the data, with the purpose of identifying whether the normal severity reflects the real impact and urgency, to investigate if there are bugs (initially classified as normal) that could be classified with other severity, and to assess if there are impacts for developers in this context. For this, an automatic classifier was developed, which was based on three algorithms (Näive Bayes, Max Ent and Winnow) to assess if normal severity is correct for the bugs categorized initially with this severity. The algorithms presented accuracy of about 80%, and showed that between 21% and 36% of the bugs should have been classified differently (depending on the algorithm), which represents somewhere between 70,000 and 130,000 bugs of the dataset.
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Peer reviewed
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Peer reviewed
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The greater part of this Monograph is devoted to detailed descriptions of 1426 samples of deposits from the floor of the Atlantic Ocean stored in the Challenger Office, Edinburgh, which had been collected during thirty-five cruising expeditions between 1857 and 1911. The remaining part discusses the results of the work. The work of examining and describing in detail this abundant mass of material was in progress when the late Sir JOHN MURRAY met his death in March 1914. By that time about three-fourths of the descriptive work had been completed under his supervision. Sir John's trustees arranged for the completion of the descriptive work by Mr Chumley, and this was done in the Challenger Office during the two succeeding years. Later, after he had removed to Glasgow, Mr Chumley prepared the notes discussing the results. The trustees have pleasure in recording, on the suggestion of Mr Chumley, the courtesy of Dr G. W. Lee of the Geological Survey of Scotland, for help in determining many of the rarer mineral particles contained in the deposits.
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With the development of the Internet-of-Things, more and more IoT platforms come up with different structures and characteristics. Making balance of their advantages and disadvantages, we should choose the suitable platform in differ- ent scenarios. For this project, I make comparison of a cloud-based centralized platform, Microsoft Azure IoT hub and a fully distributed platform, Sensi- bleThings. Quantitative comparison is made for performance by 2 scenarios, messages sending speed adds up, devices lie in different location. General com- parison is made for security, utilization and the storage. Finally I draw the con- clusion that SensibleThings performs more stable when a lot of messages push- es to the platform. Microsoft Azure has better geographic expansion. For gener- al comparison, Microsoft Azure IoT hub has better security. The requirement of local device for Microsoft Azure IoT hub is lower than SensibleThings. The SensibleThings are open source and free while Microsoft Azure follow the con- cept “pay as you go” with many throttling limitations for different editions. Microsoft is more user-friendly.
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Lors du transport du bois de la forêt vers les usines, de nombreux événements imprévus peuvent se produire, événements qui perturbent les trajets prévus (par exemple, en raison des conditions météo, des feux de forêt, de la présence de nouveaux chargements, etc.). Lorsque de tels événements ne sont connus que durant un trajet, le camion qui accomplit ce trajet doit être détourné vers un chemin alternatif. En l’absence d’informations sur un tel chemin, le chauffeur du camion est susceptible de choisir un chemin alternatif inutilement long ou pire, qui est lui-même "fermé" suite à un événement imprévu. Il est donc essentiel de fournir aux chauffeurs des informations en temps réel, en particulier des suggestions de chemins alternatifs lorsqu’une route prévue s’avère impraticable. Les possibilités de recours en cas d’imprévus dépendent des caractéristiques de la chaîne logistique étudiée comme la présence de camions auto-chargeurs et la politique de gestion du transport. Nous présentons trois articles traitant de contextes d’application différents ainsi que des modèles et des méthodes de résolution adaptés à chacun des contextes. Dans le premier article, les chauffeurs de camion disposent de l’ensemble du plan hebdomadaire de la semaine en cours. Dans ce contexte, tous les efforts doivent être faits pour minimiser les changements apportés au plan initial. Bien que la flotte de camions soit homogène, il y a un ordre de priorité des chauffeurs. Les plus prioritaires obtiennent les volumes de travail les plus importants. Minimiser les changements dans leurs plans est également une priorité. Étant donné que les conséquences des événements imprévus sur le plan de transport sont essentiellement des annulations et/ou des retards de certains voyages, l’approche proposée traite d’abord l’annulation et le retard d’un seul voyage, puis elle est généralisée pour traiter des événements plus complexes. Dans cette ap- proche, nous essayons de re-planifier les voyages impactés durant la même semaine de telle sorte qu’une chargeuse soit libre au moment de l’arrivée du camion à la fois au site forestier et à l’usine. De cette façon, les voyages des autres camions ne seront pas mo- difiés. Cette approche fournit aux répartiteurs des plans alternatifs en quelques secondes. De meilleures solutions pourraient être obtenues si le répartiteur était autorisé à apporter plus de modifications au plan initial. Dans le second article, nous considérons un contexte où un seul voyage à la fois est communiqué aux chauffeurs. Le répartiteur attend jusqu’à ce que le chauffeur termine son voyage avant de lui révéler le prochain voyage. Ce contexte est plus souple et offre plus de possibilités de recours en cas d’imprévus. En plus, le problème hebdomadaire peut être divisé en des problèmes quotidiens, puisque la demande est quotidienne et les usines sont ouvertes pendant des périodes limitées durant la journée. Nous utilisons un modèle de programmation mathématique basé sur un réseau espace-temps pour réagir aux perturbations. Bien que ces dernières puissent avoir des effets différents sur le plan de transport initial, une caractéristique clé du modèle proposé est qu’il reste valable pour traiter tous les imprévus, quelle que soit leur nature. En effet, l’impact de ces événements est capturé dans le réseau espace-temps et dans les paramètres d’entrée plutôt que dans le modèle lui-même. Le modèle est résolu pour la journée en cours chaque fois qu’un événement imprévu est révélé. Dans le dernier article, la flotte de camions est hétérogène, comprenant des camions avec des chargeuses à bord. La configuration des routes de ces camions est différente de celle des camions réguliers, car ils ne doivent pas être synchronisés avec les chargeuses. Nous utilisons un modèle mathématique où les colonnes peuvent être facilement et naturellement interprétées comme des itinéraires de camions. Nous résolvons ce modèle en utilisant la génération de colonnes. Dans un premier temps, nous relaxons l’intégralité des variables de décision et nous considérons seulement un sous-ensemble des itinéraires réalisables. Les itinéraires avec un potentiel d’amélioration de la solution courante sont ajoutés au modèle de manière itérative. Un réseau espace-temps est utilisé à la fois pour représenter les impacts des événements imprévus et pour générer ces itinéraires. La solution obtenue est généralement fractionnaire et un algorithme de branch-and-price est utilisé pour trouver des solutions entières. Plusieurs scénarios de perturbation ont été développés pour tester l’approche proposée sur des études de cas provenant de l’industrie forestière canadienne et les résultats numériques sont présentés pour les trois contextes.