683 resultados para 13200-077
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Background: Findings from the phase 3 FLEX study showed that the addition of cetuximab to cisplatin and vinorelbine significantly improved overall survival, compared with cisplatin and vinorelbine alone, in the first-line treatment of EGFR-expressing, advanced non-small-cell lung cancer (NSCLC). We investigated whether candidate biomarkers were predictive for the efficacy of chemotherapy plus cetuximab in this setting. Methods: Genomic DNA extracted from formalin-fixed paraffin-embedded (FFPE) tumour tissue of patients enrolled in the FLEX study was screened for KRAS codon 12 and 13 and EGFR kinase domain mutations with PCR-based assays. In FFPE tissue sections, EGFR copy number was assessed by dual-colour fluorescence in-situ hybridisation and PTEN expression by immunohistochemistry. Treatment outcome was investigated according to biomarker status in all available samples from patients in the intention-to-treat population. The primary endpoint in the FLEX study was overall survival. The FLEX study, which is ongoing but not recruiting participants, is registered with ClinicalTrials.gov, number NCT00148798. Findings: KRAS mutations were detected in 75 of 395 (19%) tumours and activating EGFR mutations in 64 of 436 (15%). EGFR copy number was scored as increased in 102 of 279 (37%) tumours and PTEN expression as negative in 107 of 303 (35%). Comparisons of treatment outcome between the two groups (chemotherapy plus cetuximab vs chemotherapy alone) according to biomarker status provided no indication that these biomarkers were of predictive value. Activating EGFR mutations were identified as indicators of good prognosis, with patients in both treatment groups whose tumours carried such mutations having improved survival compared with those whose tumours did not (chemotherapy plus cetuximab: median 17·5 months [95% CI 11·7-23·4] vs 8·5 months [7·1-10·8], hazard ratio [HR] 0·52 [0·32-0·84], p=0·0063; chemotherapy alone: 23·8 months [15·2-not reached] vs 10·0 months [8·7-11·0], HR 0·35 [0·21-0·59], p<0·0001). Expression of PTEN seemed to be a potential indicator of good prognosis, with patients whose tumours expressed PTEN having improved survival compared with those whose tumours did not, although this finding was not significant (chemotherapy plus cetuximab: median 11·4 months [8·6-13·6] vs 6·8 months [5·9-12·7], HR 0·80 [0·55-1·16], p=0·24; chemotherapy alone: 11·0 months [9·2-12·6] vs 9·3 months [7·6-11·9], HR 0·77 [0·54-1·10], p=0·16). Interpretation: The efficacy of chemotherapy plus cetuximab in the first-line treatment of advanced NSCLC seems to be independent of each of the biomarkers assessed. Funding: Merck KGaA. © 2011 Elsevier Ltd.
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A pulsed impinging jet is used to simulate the gust front of a thunderstorm downburst. This work concentrates on investigating the peak transient loading conditions on a 30 mm cubic model submerged in the simulated downburst flow. The outflow induced pressures are recorded and compared to those from boundary layer and steady wall jet flow. Given that peak winds associated with downburst events are often located in the transient frontal region, the importance of using a non-stationary modelling technique for assessing peak downburst wind loads is highlighted with comparisons.
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Novel nano zero-valent iron/palygorskite composite materials prepared by evaporative and centrifuge methods are tested for the degradation of bisphenol A in an aqueous medium. A systematic study is presented which showed that nano zero-valent iron material has little effect on bisphenol A degradation. When hydrogen peroxide was added to initiate the reaction, some percentage of bisphenol A removal (∼20%) was achieved; however, with the aid of air bubbles, the percentage removal can be significantly increased to ∼99%. Compared with pristine nano zero-valent iron and commercial iron powder, nano zero-valent iron/palygorskite composite materials have much higher reactivity towards bisphenol A and these materials are superior as they have little impact on the solution pH. However, for pristine nano zero-valent iron, it is difficult to maintain the reaction system at a favourable low pH which is a key factor in maintaining high bisphenol A removal. All materials were characterized by X-ray diffraction, scanning electron microscopy, elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. The optimum conditions were obtained based on a series of batch experiments. This study has extended the application of nano zero-valent iron/palygorskite composites as effective materials for the removal of phenolic compounds from the environment.
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We present a determination of Delta(f)H(298)(HOO) based upon a negative. ion thermodynamic cycle. The photoelectron spectra of HOO- and DOO- were used to measure the molecular electron affinities (EAs). In a separate experiment, a tandem flowing afterglow-selected ion flow tube (FA-SIFT) was used to measure the forward and reverse rate constants for HOO- + HCdropCH reversible arrow HOOH + HCdropC(-) at 298 K, which gave a value for Delta(acid)H(298)(HOO-H). The experiments yield the following values: EA(HOO) = 1.078 +/- 0.006 eV; T-0((X) over tilde HOO - (A) over tilde HOO) = 0.872 +/- 0.007 eV; EA(DOO) = 1.077 +/- 0.005 eV; T-0((X) over tilde DOO - (A) over tilde DOO) = 0.874 +/- 0.007 eV; Delta(acid)G(298)(HOO-H) = 369.5 +/- 0.4 kcal mol(-1); and Delta(acid)H(298)(HOO-H) = 376.5 +/- 0.4 kcal mol(-1). The acidity/EA thermochemical cycle yields values for the bond enthalpies of DH298(HOO-H) = 87.8 +/- 0.5 kcal mol(-1) and Do(HOO-H) = 86.6 +/- 0.5 kcal mol(-1). We recommend the following values for the heats of formation of the hydroperoxyl radical: Delta(f)H(298)(HOO) = 3.2 +/- 0.5 kcal mol(-1) and Delta(f)H(0)(HOO) = 3.9 +/- 0.5 kcal mol(-1); we recommend that these values supersede those listed in the current NIST-JANAF thermochemical tables.
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This paper reports on the use of a local order measure to quantify the spatial ordering of a quantum dot array (QDA). By means of electron ground state energy analysis in a quantum dot pair, it is demonstrated that the length scale required for such a measure to characterize the opto-electronic properties of a QDA is of the order of a few QD radii. Therefore, as local order is the primary factor that affects the opto-electronic properties of an array of quantum dots of homogeneous size, this order was quantified through using the standard deviation of the nearest neighbor distances of the quantum dot ensemble. The local order measure is successfully applied to quantify spatial order in a range of experimentally synthesized and numerically generated arrays of nanoparticles. This measure is not limited to QDAs and has wide ranging applications in characterizing order in dense arrays of nanostructures.
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In this paper conditional hidden Markov model (HMM) filters and conditional Kalman filters (KF) are coupled together to improve demodulation of differential encoded signals in noisy fading channels. We present an indicator matrix representation for differential encoded signals and the optimal HMM filter for demodulation. The filter requires O(N3) calculations per time iteration, where N is the number of message symbols. Decision feedback equalisation is investigated via coupling the optimal HMM filter for estimating the message, conditioned on estimates of the channel parameters, and a KF for estimating the channel states, conditioned on soft information message estimates. The particular differential encoding scheme examined in this paper is differential phase shift keying. However, the techniques developed can be extended to other forms of differential modulation. The channel model we use allows for multiplicative channel distortions and additive white Gaussian noise. Simulation studies are also presented.
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Objective Migraine is a highly disabling disease affecting a significant proportion of the Australian population. The Methylenetetrahydrofolate Reductase (MTHFR) C677T variant has been associated with increased levels of homocysteine and risk of migraine with aura (MA). Folic acid, Vitamin B6 and B12 supplementation has been previously shown to reduce increased levels of homocysteine and decrease migraine symptoms. However the influence of dietary folate intake on migraine has been unclear. The aim of the current study was to analyse the association of dietary folate intake in the form of dietary folate equivalent (DFE), folic acid (FA) and total food folate (TFF) on migraine frequency, severity and disability. Methods A cohort of 141 adult females of Caucasian descent with MA was genotyped for the MTHFRC677T variant using restriction enzyme digestion. Dietary folate information was collected from all participants and analysed using the “FoodWorks” 2009 package. Folate consumption was compared to migraine frequency, severity and disability using linear regression. Results A significant inverse relation was observed between DFE [R2= 0.201, P= 0.045, CI (-0.004, -0.001)] and FA [R2= 0.255, P= 0.036, 95% CI (-0.009, -0.002)] consumption and migraine frequency. It was also observed that in individuals with the CC genotype for the MTHFR C677T variant, migraine frequency was significantly linked to FA consumption [R2= 0.077, P= 0.029, CI (-0.009, -0.005)]. Conclusions The results from this study indicate that folate intake in the form of folic acid may influence migraine frequency in female MA sufferers.
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This study investigates the rates of primary psychotic disorders (PPD) and substance induced psychotic disorders (SIPDs) in methamphetamine (MA) users accessing needle and syringe programs (NSPs). The aim was to determine if there are systematic differences in the characteristics of MA users with PPDs and SIPDs compared to those with no psychotic disorder. Participants were 198 MA users reporting use in the previous month. Diagnosis was determined using the Psychiatric Research Interview for DSM-IV Substance and Mental Disorders (PRISM-IV). Current psychiatric symptoms and substance use were also measured. Just over half (N=101) of participants met DSM-IV criteria for a lifetime psychotic disorder, including 81 (80%) with a SIPD and 20 (20%) with a PPD. Those with a younger age of onset of weekly MA use were at increased risk of a lifetime SIPD. A current psychotic disorder was found in 62 (39%), comprising 49 SIPDs (79%) and 13 PPDs (21%). MA users with a current PPD were more likely to have received psychiatric treatment in the past month than those with a current SIPD, despite a similar level of psychotic symptom severity. A high proportion of MA users accessing NSPs have psychotic disorders, the majority of which are substance-induced.
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Mr=300.33 , triclinic, P1, a=5.635 (2), b=11.077(2), c=11.582(2)A, a= 70.48 (1), fl= 88.16 (3), y=80.56(3) ° , V= 670.325 A3, Z=2, D x = 1.49 Mg m -3, Cu Ka, n= 1.54184 ,A, g = 2.308mm -1, F(000)=316, T=301K, R=0.054, R w = 0.093 for 1944 observed counter reflections. The sulphur position with respect to the dihydrouracil ring, which is of possible relevance to the action of thymidylate synthetase, is axial in molecule A and equatorial in B. Both molecules show the anti conformation about the glycosidic bond [torsion angle C(6)-N(1)-C(1')-O(4'), 2'CN = 21.6 (9) and 29.4 (10) °] and have the C(4')-endo, O(4')-exo (40T) sugar conformation. The dioxolane-ring conformation is O(2')-endo in A and C(7)-endo in B. The dihydrouracil rings show self base pairing with hydrogen bondsN(3A)...O(ZB) and N(3B)...O(ZA).
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The physicochemical and functional properties of flours from 25 Papua New Guinean and Australian sweetpotato cultivars were evaluated. The cultivars (white-, orange-, cream-, and purple-fleshed, and with dry matter, from 15 to 28 g/100 g), were obovate, oblong, elliptic, curved, irregular in shape, and essentially thin-cortexed (1-2 mm). Flour yield was less than 90 g/100 g solids, while starch, protein, amylose, water absorption and solubility indices, as well as total sugars, varied significantly (p < 0.05). Potassium, sodium, calcium, and phosphorus were the major minerals measured, and there were differences in the pasting properties, which showed four classes of shear-thinning and shear-thickening behaviours. Differential scanning calorimetry showed single-stage gelatinisation behaviour, with cultivar-dependent temperatures (61-84 degrees C) and enthalpies (12-27 J/g dry starch). Oval-, round- and angular-shaped granules were observed with a scanning electron microscope, while X-ray diffraction revealed an A-type diffraction pattern in the cultivars, with about 30% crystallinity. This study shows a wide range of sweetpotato properties, reported for the first time.
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C 15H 1602 (a synthetic precursor to dodecahedrane), monoclinic, P21/n, a = 12.171 (5), b = 6.976(5), c = 13.868 (3) A, B = 102.56 (3) ° , Z = 4, D m = 1.30, D c = 1.318 g cm -3, F(000) = 488, g(Mo K¢t) = 0.92 cm- 1. Intensity data were collected on a Nonius CAD-4 diffractometer and the structure was solved by direct methods. Full-matrix least-squares refinement gave R = 0.077 (R w = 0.076) for 1337 observed reflections. All the five-membered rings are cis fused and have envelope (C s symmetry) conformations.
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The crystal structure of ferroelectric sodium meta vanadate, NaVO3 has been solved using three dimensional X-ray data and refined to an R-value of 0.077 for 375 observed reflections. The crystal belongs to the monoclinic system with space group Cc and with unit cell dimensions a = 10.494 (9) Aring, b = 9.434 (7) Aring, c = 5.863 (6) Aring and β = 108° 48' in the room temperature ferroelectric phase. The unit cell dimensions in the high temperature paraelectric phase (above 380°C) are a = 10.595 (15) Aring, b = 9.671 (10) Aring, c = 5.926 (8) Aring and β = 108° 45' with space group C2/c. The crystal structure may be viewed as consisting of alternate channels of sodium polyhedra and VO4 tetrahedra.
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Internationally there is a growing interest in the mental wellbeing of young people. However, it is unclear whether mental wellbeing is best conceptualized as a general wellbeing factor or a multidimensional construct. This paper investigated whether mental wellbeing, measured by the Mental Health Continuum-Short Form (MHC-SF), is best represented by: (1) a single-factor general model; (2) a three-factor multidimensional model or (3) a combination of both (bifactor model). 2,220 young Australians aged between 16 and 25 years completed an online survey including the MHC-SF and a range of other wellbeing and mental ill-health measures. Exploratory factor analysis supported a bifactor solution, comprised of a general wellbeing factor, and specific group factors of psychological, social and emotional wellbeing. Confirmatory factor analysis indicated that the bifactor model had a better fit than competing single and three-factor models. The MHC-SF total score was more strongly associated with other wellbeing and mental ill-health measures than the social, emotional or psychological subscale scores. Findings indicate that the mental wellbeing of young people is best conceptualized as an overarching latent construct (general wellbeing) to which emotional, social and psychological domains contribute. The MHC-SF total score is a valid and reliable measure of this general wellbeing factor.
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An apolar helical decapeptide with different end groups, Boc- or Ac-, crystallizes in a completely parallel fashion for the Boc-analog and in an antiparallel fashion for the Ac-analog. In both crystals, the packing motif consists of rows of parallel molecules. In the Boc-crystals, adjacent rows assemble with the helix axes pointed in the same direction. In the Ac-crystals, adjacent rows assemble with the helix axes pointed in opposite directions. The conformations of the molecules in both crystals are quite similar, predominantly alpha-helical, except for the tryptophanyl side chain where chi 1 congruent to 60 degrees in the Boc- analog and congruent to 180 degrees in the Ac-analog. As a result, there is one lateral hydrogen bond between helices, N(1 epsilon)...O(7), in the Ac-analog. The structures do not provide a ready rationalization of packing preference in terms of side-chain interactions and do not support a major role for helix dipole interactions in determining helix orientation in crystals. The crystal parameters are as follow. Boc-analog: C60H97N11O13.C3H7OH, space group Pl with a = 10.250(3) A, b = 12.451(4) A, c = 15.077(6) A, alpha = 96.55(3) degrees, beta = 92.31(3) degrees, gamma = 106.37(3) degrees, Z = 1, R = 5.5% for 5581 data ([F] greater than 3.0 sigma(F)), resolution 0.89 A. Ac-analog: C57H91N11O12, space group P2(1) with a = 9.965(1) A, b = 19.707(3) A, c = 16.648(3) A, beta = 94.08(1), Z = 2, R = 7.2% for 2530 data ([F] greater than 3.0 sigma(F)), resolution 1.00 A.
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The reported incidence of human campylobacteriosis in Finland is higher than in most other European countries. A high annual percentage of sporadic infections is of foreign origin, although a notable proportion of summer infections is domestically acquired. While chickens appear to be a major source of campylobacters for humans in most countries, the prevalence of campylobacters is very low in chicken slaughter batches in Finland. Data on other potential animal reservoirs of human pathogenic campylobacters in Finland are scarce. Consequently, this study aimed to investigate the status of Finnish cattle as a potential source of thermophilic Campylobacter spp. and antibiotic-resistant Campylobacter jejuni for human sporadic campylobacter infections of domestic origin. A survey of the prevalence of thermophilic Campylobacter spp. in Finnish cattle studied bovine rectal faecal samples (n=952) and carcass surface samples (n=948) from twelve Finnish slaughterhouses from January to December 2003. The total prevalence of Campylobacter spp. in faecal samples was 31.1%, and in carcass samples 3.5%. Campylobacter jejuni, the most common species, was present in 19.5% of faecal samples and in 3.1% of carcasses. In addition to thermophilic Campylobacter spp., C. hyointestinalis ssp. hyointestinalis was present in bovine samples. The prevalence of campylobacters was higher among beef cattle than among dairy cattle. Using the enrichment method, the number of positive faecal samples was 7.5 times higher than that obtained by direct plating. The predominant serotypes of faecal C. jejuni, determined by serotyping with a set of 25 commercial antisera for heat-stable antigens (Penner), were Pen2 and Pen4-complex, which covered 52% of the samples. Genotyping with pulsed-field gel electrophoresis (PFGE) using SmaI restriction yielded a high diversity of C. jejuni subtypes in cattle. Determining the minimum inhibitory concentrations of ampicillin, enrofloxacin, erythromycin, gentamicin, nalidixic acid, and oxytetracycline among bovine C. jejuni isolates using a commercial broth microdilution method yielded 9% of isolates resistant to at least one of the antimicrobials examined. No multiresistant isolates were found among the bovine C. jejuni strains. The study of the shedding patterns of Campylobacter spp. among three Finnish dairy cattle herds included the examination of fresh faecal samples and tank milk samples taken five times, as well as samples from drinking troughs taken once during the one-year study. The semiquantitative enrichment method detected C. jejuni in 169 of the 340 faecal samples, mostly at low levels. In addition, C. jejuni was present in one drinking trough sample. The prevalence between herds and sampling occasions varied widely. PFGE, using SmaI as restriction enzyme, identified only a few subtypes in each herd. In two 2 of the herds, two subtypes persisted throughout the sampling. Individual animals presented various shedding patterns during the study. Comparison of C. jejuni isolates from humans, chickens and cattle included the design of primers for four new genetic markers selected from completely sequenced C. jejuni genomes 81-176, RM1221 and NCTC 11168, and the PCR examination of domestic human isolates from southern Finland in 1996, 2002 and 2003 (n=309), chicken isolates from 2003, 2006 and 2007 (n=205), and bovine isolates from 2003 (n=131). The results revealed that bovine isolates differed significantly from human and chicken isolates. In particular, the - glutamyl transpeptidase gene was uncommon among bovine isolates. The PFGE genotyping of C. jejuni isolates, using SmaI and KpnI restriction enzymes, included a geographically representative collection of isolates from domestic sporadic human infections, chicken slaughter batches, and cattle faeces and carcasses during the seasonal peak of campylobacteriosis in the summer of 2003. The study determined that 55.4% of human isolates were indistinguishable from those of chickens and cattle. Temporal association between isolates from humans and chickens was possible in 31.4% of human infections. Approximately 19% of the human infections may have been associated with cattle. However, isolates from bovine carcasses and human cases represented different PFGE subtypes. In conclusion, this study suggests that Finnish cattle is a notable reservoir of C. jejuni, the most important Campylobacter sp. in human enteric infections. Although the concentration of these organisms in bovine faeces appeared to be low, excretion can be persistent. The genetic diversity and presence or absence of marker genes support previous suggestions of host-adapted C. jejuni strains, and may indicate variations in virulence between strains from different hosts. In addition to chickens, Finnish cattle appeared to be an important reservoir and possible source of C. jejuni in domestic sporadic human infections. However, sources of campylobacters may differ between rural and urban areas in Finland, and in general, the transmission of C. jejuni of bovine origin probably occurs via other routes than food.