982 resultados para Fk-960


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Over the last decades, the presence of methylmercury (MeHg) in the Amazon region of Brazil and its adverse human health effects have given rise to much concern. The biotransformation of MeHg occurs mainly through glutathione (GSH) in the bile mediated by conjugation with glutathione S-transferases (GST). Epidemiological evidence has shown that genetic polymorphisms may affect the metabolism of MeHg. The aim of this study was to evaluate the association between GST polymorphisms, GSH, and Hg levels in blood (B-Hg) and in hair (H-Hg) of an Amazon population chronically exposed to the metal through fish consumption. Blood and hair samples were collected from 144 volunteers (71 men, 73 women). B-Hg and H-Hg levels were determined by inductively coupled plasma-mass spectrometry, and GSH levels were evaluated by a spectrophotometric method. GSTM1 and T1 genotyping evaluation were carried out by multiplex polymerase chain reaction (PCR). Mean levels of B-Hg and H-Hg were 37.7 +/- 24.5 mu g/L and 10.4 +/- 7.4 mu g/g, respectively; GSH concentrations ranged from 0.52 to 2.89 mu M/ml of total blood. Distributions for GSTM1/T1, GSTM1/GSTT1*0, GSTM1*0/T1, and GSTM1*0/GSTT1*0 genotypes were 35.4, 22.2, 25.0, and 17.4%, respectively. GSTT1 genotype carriers presented lower levels of B-Hg and H-Hg when compared to other genotypes carriers. In addition, GSTM1*0/GSTT1*0 individuals presented higher Hg levels in blood and hair than subjects presenting any other genotypes. There appeared to be no evidence of an effect of polymorphisms on GSH levels. Therefore, our data suggest that GST polymorphisms may be associated with MeHg detoxification.

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New geochronological and geochemical constraints on Precambrian sedimentary and volcanic successions exposed in the western part of the Central Domain of the Borborema Province, NE Brazil, indicate the presence of two distinct tectono-stratigraphic complexes: Riacho Gravata and Sao Caetano. Both complexes and associated orthogneisses are referred in the literature as the Cariris Velhos belt, having depositional, extrusive, or intrusive ages within the interval 985-913 Ma. The Riacho Gravata complex consists of bimodal (but mostly felsic) volcanic and volcanoclastic rocks, muscovite+/-graphite schists, quartzites, and marble with local occurrences of banded-iron-formation. The Sao Caetano complex mainly consists of metagreywackes, marbles, calc-silicate rocks, and rare meta-mafic rocks. Meta-mafic rocks from both complexes have geochemical signatures similar to those of continental flood basalts, with epsilon Nd (1.0 Ga) values ranging from -1.0 to -2.8. Felsic volcanic rocks from the Riacho Gravata complex show epsilon Nd (1.0 Ga) values ranging from -1.0 to -7.4 and geochemical signatures similar to A(2)-type granitoids. New SHRIMP U-Pb zircon data from felsic volcanic rocks within the Riacho Gravata complex yielded ages of 1091 +/- 13 Ma and 996 +/- 13 Ma. In contrast, meta-graywackes from the Sao Caetano complex show a maximum deposition age of ca. 806 Ma in the northern part and ca. 862 Ma in the southern part of the outcrop area. The orthogneisses show epsilon Nd (1.0 Ga) values ranging from 1.0 to -4.2 with U/Pb TIMS and SHRIMP ages ranging from 960 to 926 Ma and geochemical signatures of A(2)-type granitoids. The data reported in this paper suggest at least two periods of extension within the Central Domain of the Borborema Province, the first starts ca. 1091 Ma with magmatism and deposition, creating the Riacho Gravata basin and continued intrusion of A-type granites to 920 Ma. A second rift event, which reactivated old faults, generated a basin with a maximum deposition age of ca. 806 Ma. Furthermore, the oldest granitoids cutting these metasedimentary rocks have crystallization ages of ca. 600 Ma. This suggests that the second rift event could be early Brasiliano in age. The resulting Sao Caetano basin received detritus from a variety of sources, although detritus from the Riacho Gravata complex dominated. Deposition ages of the Riacho Gravata and the Sao Caetano complexes are coeval with deposits in other basins of the Borborema Province (Riacho do Tigre in the Central Domain; Macurure and Maranco in the Sergipano Belt of the Southern domain). The Macaubas Group from SE Brazil and its counterparts in Africa, the Zadanian and Mayumbian Groups, in the western edge of the Congo Craton are also coeval. Closure of the Riacho Gravata and Sao Caetano basins occurred during the Brasiliano convergence (705-600 Ma). During the last stage of convergence, ca. 612 Ma, pull-apart basins were created and filled; final basin closure took place 605-592 Ma, after deposition ceased. (C) 2011 Elsevier B.V. All rights reserved.

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Purpose: To report the clinical outcome of the treatment of dry eyes using 0.03% tacrolimus eye drops (olive oil + tacrolimus 0.03%) (Ophthalmos, Sao Paulo, Brazil). Methods: Sixteen eyes of 8 patients with Sjogren syndrome dry eyes (age, 51.13 +/- 9.45 years) were enrolled in this study (prospective noncontrolled interventional case series). Patients were instructed to use topical 0.03% tacrolimus eye drops twice a day (every 12 hours) in the lower conjunctival sac. Schirmer I test, break-up time, corneal fluorescein, and rose bengal staining score were performed in all patients 1 day before, and 14, 28, and 90 days after treatment with 0.03% tacrolimus eye drops. Results: The average fluorescein staining and rose bengal staining scores improved statistically significantly after 14 days of treatment and improved even more after 28 and 90 days. The average Schirmer I test did not improve statistically significantly after 28 days of treatment, although we did observe a significant improvement after 90 days of treatment with 0.03% tacrolimus eye drops. The average break-up time did not improve statistically after 14 days of treatment, although we observed a significant improvement after 28 and 90 days of treatment with 0.03% tacrolimus eye drops. Conclusions: Topical 0.03% tacrolimus eye drops successfully improved tear stability and ocular surface status in patients with dry eyes.

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Background: Bevacizumab improves the efficacy of oxaliplatin-based chemotherapy in metastatic colorectal cancer. Our aim was to assess the use of bevacizumab in combination with oxaliplatin-based chemotherapy in the adjuvant treatment of patients with resected stage III or high-risk stage II colon carcinoma. Methods: Patients from 330 centres in 34 countries were enrolled into this phase 3, open-label randomised trial. Patients with curatively resected stage III or high-risk stage II colon carcinoma were randomly assigned (1: 1: 1) to receive FOLFOX4 (oxaliplatin 85 mg/m(2), leucovorin 200 mg/m(2), and fluorouracil 400 mg/m(2) bolus plus 600 mg/m(2) 22-h continuous infusion on day 1; leucovorin 200 mg/m(2) plus fluorouracil 400 mg/m(2) bolus plus 600 mg/m(2) 22-h continuous infusion on day 2) every 2 weeks for 12 cycles; bevacizumab 5 mg/kg plus FOLFOX4 (every 2 weeks for 12 cycles) followed by bevacizumab monotherapy 7.5 mg/kg every 3 weeks (eight cycles over 24 weeks); or bevacizumab 7.5 mg/kg plus XELOX (oxaliplatin 130 mg/m(2) on day 1 every 2 weeks plus oral capecitabine 1000 mg/m(2) twice daily on days 1-15) every 3 weeks for eight cycles followed by bevacizumab monotherapy 7.5 mg/kg every 3 weeks (eight cycles over 24 weeks). Block randomisation was done with a central interactive computerised system, stratified by geographic region and disease stage. Surgery with curative intent occurred 4-8 weeks before randomisation. The primary endpoint was disease-free survival, analysed for all randomised patients with stage III disease. This study is registered with ClinicalTrials.gov, number NCT00112918. Findings: Of the total intention-to-treat population (n=3451), 2867 patients had stage III disease, of whom 955 were randomly assigned to receive FOLFOX4, 960 to receive bevacizumab-FOLFOX4, and 952 to receive bevacizumab-XELOX. After a median follow-up of 48 months (range 0-66 months), 237 patients (25%) in the FOLFOX4 group, 280 (29%) in the bevacizumab-FOLFOX4 group, and 253 (27%) in the bevacizumab-XELOX group had relapsed, developed a new colon cancer, or died. The disease-free survival hazard ratio for bevacizumab-FOLFOX4 versus FOLFOX4 was 1.17 (95% CI 0.98-1.39; p=0.07), and for bevacizumab-XELOX versus FOLFOX4 was 1.07 (0.90-1.28; p=0.44). After a minimum follow-up of 60 months, the overall survival hazard ratio for bevacizumab-FOLFOX4 versus FOLFOX4 was 1.27 (1.03-1.57; p=0.02), and for bevacizumab-XELOX versus FOLFOX4 was 1.15 (0.93-1.42; p=0.21). The 573 patients with high-risk stage II cancer were included in the safety analysis. The most common grade 3-5 adverse events were neutropenia (FOLFOX4: 477 [42%] of 1126 patients, bevacizumab-FOLFOX4: 416 [36%] of 1145 patients, and bevacizumab-XELOX: 74 [7%] of 1135 patients), diarrhoea (110 [10%], 135 [12%], and 181 [16%], respectively), and hypertension (12 [1%], 122 [11%], and 116 [10%], respectively). Serious adverse events were more common in the bevacizumab groups (bevacizumab-FOLFOX4: 297 [26%]; bevacizumab-XELOX: 284 [25%]) than in the FOLFOX4 group (226 [20%]). Treatment-related deaths were reported in one patient receiving FOLFOX4, two receiving bevacizumab-FOLFOX4, and five receiving bevacizumab-XELOX. Interpretation: Bevacizumab does not prolong disease-free survival when added to adjuvant chemotherapy in resected stage III colon cancer. Overall survival data suggest a potential detrimental effect with bevacizumab plus oxaliplatin-based adjuvant therapy in these patients. On the basis of these and other data, we do not recommend the use of bevacizumab in the adjuvant treatment of patients with curatively resected stage III colon cancer.

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Auxyn type herbicides such as dicamba and 2,4-D are alternative herbicides that can be used to control glyphosate-resistant hairy fleabane. With the forthcoming possibility of releasing dicamba-resistant and 2,4-D-resistant crops, use of these growth regulator herbicides will likely be an alternative that can be applied to the control of glyphosate resistant hairy fleabane (Conyza bonariensis). The objective of this research was to model the efficacy, through dose-response curves, of glyphosate, 2,4-D, isolated dicamba and glyphosatedicamba combinations to control a brazilian hairy fleabane population resistant to glyphosate. The greenhouse dose-response studies were conducted as a completely randomized experimental design, and the rates used for dose response curve construction were 0, 120, 240, 480, 720 and 960 g a.i. ha-1 for 2,4-D, dicamba and the dicamba combination, with glyphosate at 540 g a.e. ha-1. The rates for glyphosate alone were 0, 180, 360, 540, 720 and 960 g a.e. ha-1. Herbicides were applied when the plants were in a vegetative stage with 10 to 12 leaves and height between 12 and 15 cm. Hairy fleabane had low sensitivity to glyphosate, with poor control even at the 960 g a.e. ha-1 rate. Dicamba and 2,4-D were effective in controlling the studied hairy fleabane. Hairy fleabane responds differently to 2,4-D and dicamba. The combination of glyphosate and dicamba was not antagonistic to hairy fleabane control, and glyphosate may cause an additive effect on the control, despite the population resistance.

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Objetivo: avaliar os efeitos de precondicionamento isquêmico remoto (PCI-R) no modelo de transplante de intestino delgado fetal. Métodos: foram constituídos dois grupos: transplante isogênico (Iso, camundongos C57BL/6, n=24) e transplante alogênico (Alo, camundongos BALB/c, n=24). Em cada grupo, distribuíram-se os animais com e sem PCI-R, que foi realizado por oclusão da artéria femoral esquerda da fêmea prenhe durante 10 minutos, seguida por tempo igual de reperfusão. O imunossupressor utilizado foi Tacrolimo (Fk, 5 mg/kg/dia v.o.). Ao final obteve-se os seguintes subgrupos: Alo-Tx, Alo-Pci, Alo-Fk, Alo-Pci-Fk, Iso-Tx, Iso-Pci, Iso-Fk e Iso-Pci-Fk. O enxerto foi transplantado no espaço entre o músculo reto-abdominal e pré- peritoneal dos receptores a meio centímetro do apêndice xifóide, à esquerda da linha mediana. Após o sétimo dia de seguimento, o enxerto foi removido, fixado e embebido em parafina para avaliação histomorfológica (desenvolvimento e rejeição) e análise imunohistoquímica (anti-PCNA e anti-caspase-3 clivada). Os dados foram analisados usando ANOVA e testes complementares e foi considerado significante quando p <0.05. Resultados: A avaliação do desenvolvimento do enxerto no grupo de Iso mostrou que o PCI-R reduziu o desenvolvimento comparado com Iso-Tx (5,2±0,4 vs 9,0±0,8), o Fk e sua associação com PCI-R aumentaram o desenvolvimento do enxerto comparado com PCI-R (11,2±0,7 e 10,2±0,8, respectivamente). No grupo Alo, o Fk e/ou sua associação com PCI-R aumentaram o desenvolvimento comparado com Alo-Tx e Alo com PCI-R (6,0±0,8, 9,0±1,2, 0,0±0,0, 0,5±0,3, respectivamente). A expressão de PCNA foi maior no grupo ISO em animais tratados com Fk e PCI-R comparados a outros grupos (12,2±0,8 vs Tx: 8,8±0,9, PCI-R: 8,0±0,4 e Fk: 9,0±0,6). No grupo Alo, a expressão de PCNA não diferiu entre grupos. A rejeição do enxerto foi menor nos grupos tratados com PCI-R (-18%), Fk (- 68%) ou ambos (-61%) comparados com Alo-Tx. A expressão de caspase-3 clivada foi menor no grupo Iso em animais tratados com associação de PCI-R e Fk (6,2 ±0,9 vs Tx: 8,6±0,5; PCI-R: 5,8 ±0,9 e Fk: 6,0 ±0,3). Conclusão: O PCIR mostrou efeito benéfico sobre a lesão de isquemia e reperfusão do enxerto intestinal fetal nos transplantes isogênico e alogênico, aumentando o número de células caliciformes e a proliferação celular. No transplante alogênico, aumentou o desenvolvimento do enxerto, diminuiu o grau de rejeição aguda na ausência de imunossupressão, porém não apresentou efeito sinérgico com o imunossupressor. No transplante isogênico houve diminuição do grau de desenvolvimento do enxerto, porém foi efetivo na redução da apoptose.

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This thesis presents and uses the techniques of computational chemistry to explore two different processes induced in human skin by ultraviolet light. The first is the transformation of urocanic acid into a immunosuppressing agent, and the other is the enzymatic action of the 8-oxoguanine glycosylase enzyme. The photochemistry of urocanic acid is investigated by time-dependent density functional theory. Vertical absorption spectra of the molecule in different forms and environments is assigned and candidate states for the photochemistry at different wavelengths are identified. Molecular dynamics simulations of urocanic acid in gas phase and aqueous solution reveals considerable flexibility under experimental conditions, particularly for for the cis isomer where competition between intra- and inter-molecular interactions increases flexibility. A model to explain the observed gas phase photochemistry of urocanic acid is developed and it is shown that a reinterpretation in terms of a mixture between isomers significantly enhances the agreement between theory and experiment , and resolves several peculiarities in the spectrum. A model for the photochemistry in the aqueous phase of urocanic acid is then developed, in which two excited states governs the efficiency of photoisomerization. The point of entrance into a conical intersection seam is shown to explain the wavelength dependence of photoisomerization quantum yield. Finally some mechanistic aspects of the DNA repair enzyme 8-oxoguanine glycosylase is investigated with density functional theory. It is found that the critical amino acid of the active site can provide catalytic power in several different manners, and that a recent proposal involving a SN1 type of mechanism seems the most efficient one.

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[EN] The presence of emerging contaminants has been previously described in reclaimed water and groundwater of Gran Canaria (Spain). Despite of the environmental risk associated to irrigation with reclaimed water (R), this practice is necessary considering sustainability of the hydrological cycle in semiarid zones, especially regarding agricultural activity. The aim of this study was: i) to analyse the evolution during two years of contaminants of emerging concern, priority substances (2008/105/EC) and heavy metals in reclaimed water (R) and in a volcanic aquifer in the NE of Gran Canaria where a golf course has been irrigated with R since 1976 and ii) to relate this presence with physicochemical water properties and hydrogeological media. Reclaimed water and groundwater (GW) were monitoring quarterly from July 2009 to September 2011. Sorption and degradation processes in soil account for more compounds being detected in R. Diazinon and chlorfenvinphos were detected always in R and terbuthylazine, terbutryn and diuron at 90% of frequency. Considering all the samples, the most frequent compounds were chlorpyrifos ethyl, fluorene, phenanthrene and pyrene. Although their concentrations were frequently below 50 ngL-1, some contaminants, were occasionally detected at higher concentrations. Chlorpyrifos ethyl and diuron are priority substances detected frequently and at high concentrations so they must be included in monitoring studies. Geology and location seem to be related to the emerging compounds presence due to occasional contamination events (not related to R irrigation) and therefore not to an existence of a dangerous diffuse contamination level. Thus, it is preferable to select wells with less stable chemical water quality, in order to monitor the risk of emerging compounds presence. Considering the relationship between contaminant presence, chemical water quality, seasonal variation, hydrogeological characteristics and wells location we can conclude that chlorpyrifos ethyl and diuron were the most dangerous priority substances in terms of GW quality so they must be included in all of the monitoring studies, at least in Canary Islands.

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The inherent stochastic character of most of the physical quantities involved in engineering models has led to an always increasing interest for probabilistic analysis. Many approaches to stochastic analysis have been proposed. However, it is widely acknowledged that the only universal method available to solve accurately any kind of stochastic mechanics problem is Monte Carlo Simulation. One of the key parts in the implementation of this technique is the accurate and efficient generation of samples of the random processes and fields involved in the problem at hand. In the present thesis an original method for the simulation of homogeneous, multi-dimensional, multi-variate, non-Gaussian random fields is proposed. The algorithm has proved to be very accurate in matching both the target spectrum and the marginal probability. The computational efficiency and robustness are very good too, even when dealing with strongly non-Gaussian distributions. What is more, the resulting samples posses all the relevant, welldefined and desired properties of “translation fields”, including crossing rates and distributions of extremes. The topic of the second part of the thesis lies in the field of non-destructive parametric structural identification. Its objective is to evaluate the mechanical characteristics of constituent bars in existing truss structures, using static loads and strain measurements. In the cases of missing data and of damages that interest only a small portion of the bar, Genetic Algorithm have proved to be an effective tool to solve the problem.

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Il lavoro svolto, in collaborazione con “Ducati Motor Holding”, si propone l’analisi, mediante l’applicazione di un software FEM (HyperWorks 9.0), delle strutture rappresentate dall’assieme paracoppa-parasassi e dal silenziatore. Il primo obiettivo consiste nell’ottenimento di un modello agli elementi finiti della struttura. Le simulazioni di calcolo consistono in analisi di tipo dinamico per determinare i modi di vibrare delle strutture. Sulla base di ulteriori simulazioni sulla risposta al transitorio del sistema si è studiato il loro comportamento nelle condizioni di funzionamento. La finalità del lavoro risiede dunque nella determinazione delle criticità strutturali che i componenti hanno manifestato durante prove sperimentali verificandole attraverso calcolo numerico e applicazione delle potenzialità del software applicato, per l’analisi degli aspetti sopra esposti.

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In dieser Arbeit werden zehn neue symmetrische (176,50,14) Designs und ein neues symmetrisches (144,66,30) Design durch Vorgabe von nichtauflösbaren Automorphismengruppen konstruiert. Im Jahre 1969 entdeckte G. Higman ein symmetrisches (176,50,14) Design, dessen volle Automorphismengruppe die sporadische einfache Gruppe HS der Ordnung 44.352.000 ist. Hier wurden nun Designs gesucht, die eine Untergruppe von HS zulassen. Folgende Untergruppen wurden betrachtet: die transitive und die intransitive Erweiterung einer elementarabelschen Gruppe der Ordnung 16 durch Alt(5), AGL(3,2), das direkte Produkt einer zyklischen Gruppe der Ordnung 5 mit Alt(5) und PSL(2,11). Die transitive Erweiterung von E(16) durch Alt(5) lieferte zwei neue Designs mit Automorphismengruppen der Ordnungen 960 bzw. 11.520; letzteres konnte auch mit der transitiven Erweiterung erhalten werden. Die Gruppe PSL(2,11) operiert auf den Punkten des Higman-Designs in drei Bahnen; sucht man nach symmetrischen (176,50,14) Designs, auf denen diese Gruppe in zwei Bahnen operiert, so erhält man acht neue Designs. Die übrigen Gruppen lieferten keine neuen Designs. Schließlich konnte ein neues symmetrisches (144,66,30) Design unter Verwendung der sporadischen Mathieu-Gruppe M(12) konstruiert werden. Dies war zu diesem Zeitpunkt außer dem Higman-Design das einzige bekannte symmetrische Design, dessen volle Automorphismengruppe im Wesentlichen eine sporadische einfache Gruppe ist.

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Im Rahmen der vorliegenden Arbeit wurde erstmals Laser-Atomspektroskopie an einem Element durchgeführt, für das bisher keine atomaren Niveaus bekannt waren. Die Experimente wurden am Element Fermium mit der Ordnungszahl Z=100 mit der Resonanzionisationsspektroskopie (RIS) in einer Puffergaszelle durchgeführt. Verwendet wurde das Isotop 255Fm mit einer Halbwertszeit von 20.1 h, das im Hochflusskernreaktor des ORNL, Oak Ridge, USA, hergestellt wurde. Die von einem elektrochemischen Filament in das Argon-Puffergas bei einer Temperatur von 960(20)°C abgedampften Fm-Atome wurden mit Lasern in einem Zweistufenprozess resonant ionisiert. Dazu wurde das Licht eines Excimerlaser gepumpten Farbstofflasers für den ersten Anregungsschritt um die Wellenlänge 400 nm durchgestimmt. Ein Teil des Excimer (XeF) Laser Pumplichtes mit den Wellenlänge 351/353 nm wurde für die nicht-resonante Ionisation verwendet. Die Ionen wurden mit Hilfe elektrischer Felder aus der optischen Zelle extrahiert und nach einem Quadrupol Massenfilter mit einem Channeltron-Detektor massenselektiv nachgewiesen. Trotz der geringen Probenmenge von 2.7 x 10^10 eingesetzten Atomen wurden zwei atomare Resonanzen bei Energien von 25099.8(2) cm-1 und 25111.8(2) cm-1 gefunden und das Sättigungsverhalten dieser Linien gemessen. Es wurde ein theoretisches Modell entwickelt, dass sowohl das spektrale Profil der sättigungsverbreiterten Linien als auch die Sättigungskurven beschreibt. Durch Anpassung an die Messdaten konnten die partiellen Übergangsraten in den 3H6 Grundzustand Aki=3.6(7) x 10^6/s und Aki=3.6(6) x 10^6/s bestimmt werden. Der Vergleich der Niveauenergien und Übergangsraten mit Multikonfigurations Dirac-Fock Rechnungen legt die spektroskopische Klassifizierung der beobachteten Niveaus als 5f12 7s7p 5I6 und 5G6 Terme nahe. Weiterhin wurde ein Übergang bei 25740 cm-1 gefunden, der aufgrund der beobachteten Linienbreite von 1000 GHz als Rydbergzustand Zustand mit der Niveauenergie 51480 cm-1 interpretiert wurde und über einen Zweiphotonen Prozess angeregt werden kann. Basierend auf dieser Annahme wurde die Obergrenze für die Ionisationsenergie IP = 52140 cm-1 = 6.5 eV abgeschätzt. In den Messungen wurden Verschiebungen in den Zeitverteilungsspektren zwischen den mono-atomaren Ionen Fm+ und Cf+ und dem Molekül-Ion UO+ festgestellt und auf Driftzeitunterschiede im elektrischen Feld der gasgefüllten optischen Zelle zurückgeführt. Unter einfachen Modellannahmen wurde daraus auf die relativen Unterschiede Delta_r(Fm+,Cf+)/r(Cf+) ˜ -0.2 % und Delta_r(UO+,Cf+)/r(Cf+) ˜ 20 % in den Ionenradien geschlossen. Über die Bestimmung der Abnahme der Fm-a Aktivität des Filamentes auf der einen Seite und die Messung der Resonanzzählrate auf der anderen Seite, wurde die Nachweiseffizienz der Apparatur zu 4.5(3) x 10^-4 bestimmt. Die Nachweisapparatur wurde mit dem Ziel weiterentwickelt, Laserspektroskopie am Isotop 251Fm durchzuführen, das über die Reaktion 249Cf(a,2n)251Fm direkt in der optischen Zelle erzeugt werden soll. Das Verfahren wurde am chemischen Homolog Erbium getestet. Dabei wurde das Isotop 163Er über die Reaktion 161Dy(a,2n)163Er erzeugt und nach Resonanzionisation nachgewiesen. Die Nachweiseffizienz der Methode wurde zu 1 x 10^-4 bestimmt.

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Preface: The improvements of the social-environmental conditions, and medical cares and the quality of life caused a general improvement of the health status of the population, with a consequent reduction of the overall morbidity and mortality, resulting in an increase of life expectancy that has rose dramatically in the last century. Stroke represents the 3rd cause of death and 1st cause of disability in Europe and in Italy. Aim: The aim of this research is to explore the prevalence of stroke in 1.176 90+ Italian sibs, collected from the north, centre and south of the peninsula, and examine the presence of functional and cognitive disability in the stroke affected sibs. Materials and Methods: We divided our sample in three main categories a)Stroke free(960 subjects, 88.72%), b)Young age stroke, reported age of Stroke incidence < 85 y.o.(42 subjects, 3.88%), c)Old age stroke, reported age of Stroke incidence ≥ 85y.o.(80 subjects, 7.39%). We examine cognitive impairment using the MMSE and functional disability using the ADL scale, the chair stand and hand-grip test. The three groups for each test have been analysed according the following parameters: age at interview, sex, ability to understand the questions, can the participant walk 500 m without help, smoke habit, alcohol daily consumption, presence of serious memory impairments (e.g. dementia), Daily Exercise or daily light housework, History of arthritis. Results: After performing mulrivariate analysis, amazingly the young ictus group had worst performance in all the cognitive and functional variables.