996 resultados para Without Buffer Gas


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OBJECTIVE: Although sleep is a biomarker for general health and pathological conditions, its changes across age and gender are poorly understood. METHODS: Subjective evaluation of sleep was assessed by questionnaires in 5,064 subjects, and 2,966 were considered without sleep disorders. Objective evaluation was performed by polysomnography in 2,160 subjects, and 1,147 were considered without sleep disorders. Only subjects without sleep disorders were included (aged 40-80 years). RESULTS: Aging was strongly associated with morning preference. Older subjects, especially women, complained less about sleepiness, and pathological sleepiness was significantly lower than in younger subjects. Self-reported sleep quality and daytime functioning improved with aging. Sleep latency increased with age in women, while sleep efficiency decreased with age in both genders. Deep slow-wave sleep decreased with age, but men were more affected. Spectral power densities within slow waves (< 5 Hz) and fast spindles (14-14.75 Hz) decreased, while theta-alpha (5-1 Hz) and beta (16.75-25 Hz) power in non-rapid eye movement sleep increased with aging. In REM sleep, aging was associated with a progressive decrease in delta (1.25-4.5 Hz) and increase in higher frequencies. CONCLUSIONS: Our findings indicate that sleep complaints should not be viewed as part of normal aging but should prompt the identification of underlying causes.

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BACKGROUND & AIMS: The standard liver volume (SLV) is widely used in liver surgery, especially for living donor liver transplantation (LDLT). All the reported formulas for SLV use body surface area or body weight, which can be influenced strongly by the general condition of the patient. METHODS: We analyzed the liver volumes of 180 Japanese donor candidates and 160 Swiss patients with normal livers to develop a new formula. The dataset was randomly divided into two subsets, the test and validation sample, stratified by race. The new formula was validated using 50 LDLT recipients. RESULTS: Without using body weight-related variables, age, thoracic width measured using computed tomography, and race independently predicted the total liver volume (TLV). A new formula: 203.3-(3.61×age)+(58.7×thoracic width)-(463.7×race [1=Asian, 0=Caucasian]), most accurately predicted the TLV in the validation dataset as compared with any other formulas. The graft volume for LDLT was correlated with the postoperative prothrombin time, and the graft volume/SLV ratio calculated using the new formula was significantly better correlated with the postoperative prothrombin time than the graft volume/SLV ratio calculated using the other formulas or the graft volume/body weight ratio. CONCLUSIONS: The new formula derived using the age, thoracic width and race predicted both the TLV in the healthy patient group and the SLV in LDLT recipients more accurately than any other previously reported formulas.

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A headspace-gas chromatography-tandem mass spectrometry (HS-GC-MS/MS) method for the trace measurement of perfluorocarbon compounds (PFCs) in blood was developed. Due to oxygen carrying capabilities of PFCs, application to doping and sports misuse is speculated. This study was therefore extended to perform validation methods for F-tert-butylcyclohexane (Oxycyte(®)), perfluoro(methyldecalin) (PFMD) and perfluorodecalin (PFD). The limit of detection of these compounds was established and found to be 1.2µg/mL blood for F-tert-butylcyclohexane, 4.9µg/mL blood for PFMD and 9.6µg/mL blood for PFD. The limit of quantification was assumed to be 12µg/mL blood (F-tert-butylcyclohexane), 48µg/mL blood (PFMD) and 96µg/mL blood (PFD). HS-GC-MS/MS technique allows detection from 1000 to 10,000 times lower than the estimated required dose to ensure a biological effect for the investigated PFCs. Thus, this technique could be used to identify a PFC misuse several hours, maybe days, after the injection or the sporting event. Clinical trials with those compounds are still required to evaluate the validation parameters with the calculated estimations.

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To-date, there has been no effective chiral capillary electrophoresis-mass spectrometry (CE-MS) method reported for the simultaneous enantioseparation of the antidepressant drug, venlafaxine (VX) and its structurally-similar major metabolite, O-desmethylvenlafaxine (O-DVX). This is mainly due to the difficulty of identifying MS compatible chiral selector, which could provide both high enantioselectivity and sensitive MS detection. In this work, poly-sodium N-undecenoyl-L,L-leucylalaninate (poly-L,L-SULA) was employed as a chiral selector after screening several dipeptide polymeric chiral surfactants. Baseline separation of both O-DVX and VX enantiomers was achieved in 15min after optimizing the buffer pH, poly-L,L-SULA concentration, nebulizer pressure and separation voltage. Calibration curves in spiked plasma (recoveries higher than 80%) were linear over the concentration range 150-5000ng/mL for both VX and O-DVX. The limit of detection (LOD) was found to be as low as 30ng/mL and 21ng/mL for O-DVX and VX, respectively. This method was successfully applied to measure the plasma concentrations of human volunteers receiving VX or O-DVX orally when co-administered without and with indinivar therapy. The results suggest that micellar electrokinetic chromatography electrospray ionization-tandem mass spectrometry (MEKC-ESI-MS/MS) is an effective low cost alternative technique for the pharmacokinetics and pharmacodynamics studies of both O-DVX and VX enantiomers. The technique has potential to identify drug-drug interaction involving VX and O-DVX enantiomers while administering indinivar therapy.

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En este trabajo se presenta un estudio químico y estructural de las capas metálicas de Pt y TaSix utilizadas como puerta catalítica en sensores de gas de alta temperatura basados en dispositivos MOS de SiC. Para ello se han depositado capas de diferentes espesores sobre substratos de Si. Los resultados muestran que con la reducción del espesor de Pt y con un recocido se consigue aumentar la rugosidad de las capas de puerta, lo que debería aumentar la sensibilidad y la velocidad de respuesta de los dispositivos que las incorporasen. Otro efecto del recocido es la transformación química del material de la puerta que, para capas delgadas de Pt con TaSix, produce la transformación total Pt en Pt2Ta, lo que podría afectar a las características catalíticas de la puerta. Los primeros resultados eléctricos indican que, a pesar de que las capas de Pt empleadas son gruesas y compactas, los diodos MOS túnel de SiC son sensibles a los gases CO y NO2, aunque presentan una velocidad de respuesta bastante lenta.

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Very large molecular systems can be calculated with the so called CNDOL approximate Hamiltonians that have been developed by avoiding oversimplifications and only using a priori parameters and formulas from the simpler NDO methods. A new diagonal monoelectronic term named CNDOL/21 shows great consistency and easier SCF convergence when used together with an appropriate function for charge repulsion energies that is derived from traditional formulas. It is possible to obtain a priori molecular orbitals and electron excitation properties after the configuration interaction of single excited determinants with reliability, maintaining interpretative possibilities even being a simplified Hamiltonian. Tests with some unequivocal gas phase maxima of simple molecules (benzene, furfural, acetaldehyde, hexyl alcohol, methyl amine, 2,5 dimethyl 2,4 hexadiene, and ethyl sulfide) ratify the general quality of this approach in comparison with other methods. The calculation of large systems as porphine in gas phase and a model of the complete retinal binding pocket in rhodopsin with 622 basis functions on 280 atoms at the quantum mechanical level show reliability leading to a resulting first allowed transition in 483 nm, very similar to the known experimental value of 500 nm of "dark state." In this very important case, our model gives a central role in this excitation to a charge transfer from the neighboring Glu(-) counterion to the retinaldehyde polyene chain. Tests with gas phase maxima of some important molecules corroborate the reliability of CNDOL/2 Hamiltonians.

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Työssä vertaillaan eri sähköntuotantovaihtoehtojen taloudellista kannattavuutta. Kannattavuusvertailu suoritetaan pelkkää sähköä tuottaville voimalaitoksille. Sähkön ja lämmön yhteistuotannon lisärakentaminen tulee kattamaan tietyn osuuden lähitulevaisuuden sähkön hankinnan vajeesta, mutta sen lisäksi tarvitaan myös uutta lauhdetuotantokapasiteettia. Tutkittavat voimalaitostyypit ovat: ydinvoimalaitos, maakaasukombilauhdevoimalaitos, kivihiililauhdevoimalaitos, turvelauhdevoimalaitos, puulauhdevoimalaitos ja tuulivoimala. Kannattavuustarkastelu suoritetaan annuiteettimenetelmällä käyttäen 5 % reaalikorkoa ja tammikuun 2008 hintatasoa. Laskelmien perusteella 8000 tunnin huipunkäyttöajalla ydinsähkön tuotantokustannus olisi 35,0 € /MWh, kaasusähkön 59,2 €/MWh ja hiilisähkön 64,4 €/MWh, kun hiilidioksidipäästöoikeuden hintana käytetään 23 €/t. Ilman päästökauppaa kaasusähkön hinta on 51,2 €/MWh ja hiilisähkön 45,7 €/MWh ydinsähkön hinnan pysyessä ennallaan. Herkkyystarkastelun tulosten perusteella ydinvoiman kilpailukyky korostuu muihin tarkasteltuihin tuotantomuotoihin verrattuna. Ydinpolttoaineen suurellakaan hinnan muutoksella ei ole merkittävää vaikutusta ydinsähkön tuotantokustannukseen, kun taas maakaasusähkö on erittäin riippuvainen polttoaineen hinnasta. Myös päästöoikeuden hinnan kasvu lisää merkittävästi ydinvoiman kilpailukykyä kaasu- ja hiilisähköön verrattuna. Ydinvoimainvestoinnin kannattavuutta ja takaisinmaksua tarkastellaan myös yksinään siten, että investoinnilla saavutettavien tuottojen laskennassa käytetään useita eri sähkön markkinahintoja. Investoinnin kannattavuus on erittäin hyvä, kun sähkön markkinahinta on 50 €/MWh tai suurempi.

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Cells couple growth with division and regulate size in response to nutrient availability. In rod-shaped fission yeast, cell-size control occurs at mitotic commitment. An important regulator is the DYRK-family kinase Pom1, which forms gradients from cell poles and inhibits the mitotic activator Cdr2, itself localized at the medial cortex. Where and when Pom1 modulates Cdr2 activity is unclear as Pom1 medial cortical levels remain constant during cell elongation. Here we show that Pom1 re-localizes to cell sides upon environmental glucose limitation, where it strongly delays mitosis. This re-localization is caused by severe microtubule destabilization upon glucose starvation, with microtubules undergoing catastrophe and depositing the Pom1 gradient nucleator Tea4 at cell sides. Microtubule destabilization requires PKA/Pka1 activity, which negatively regulates the microtubule rescue factor CLASP/Cls1/Peg1, reducing CLASP's ability to stabilize microtubules. Thus, PKA signalling tunes CLASP's activity to promote Pom1 cell side localization and buffer cell size upon glucose starvation.

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This article describes a photocatalytic nanostructured anatase coating deposited by cold gas spray (CGS)supported on titanium sub-oxide (TiO22x) coatings obtained by atmospheric plasma spray (APS) onto stainless steel cylinders. The photocatalytic coating was homogeneous and preserved the composition and nanostructure of the starting powder. The inner titanium sub-oxide coating favored the deposition of anatase particles in the solid state. Agglomerated nano-TiO2 particles fragmented when impacting onto the hard surface of the APS TiO22x bond coat. The rough surface provided by APS provided an ideal scenario for entrapping the nanostructured particles, which may be adhered onto the bond coat due to chemical bonding; a possible bonding mechanism is described. Photocatalytic experiments showed that CGS nano-TiO2 coating was active for photodegrading phenol and formic acid under aqueous conditions. The results were similar to the performance obtained by competitor technologies and materials such as dip-coating P25 photocatalysts. Disparity in the final performance of the photoactive materials may have been caused by differences in grain size and the crystalline composition of titanium dioxide.

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This review presents the evolution of steroid analytical techniques, including gas chromatography coupled to mass spectrometry (GC-MS), immunoassay (IA) and targeted liquid chromatography coupled to mass spectrometry (LC-MS), and it evaluates the potential of extended steroid profiles by a metabolomics-based approach, namely steroidomics. Steroids regulate essential biological functions including growth and reproduction, and perturbations of the steroid homeostasis can generate serious physiological issues; therefore, specific and sensitive methods have been developed to measure steroid concentrations. GC-MS measuring several steroids simultaneously was considered the first historical standard method for analysis. Steroids were then quantified by immunoassay, allowing a higher throughput; however, major drawbacks included the measurement of a single compound instead of a panel and cross-reactivity reactions. Targeted LC-MS methods with selected reaction monitoring (SRM) were then introduced for quantifying a small steroid subset without the problems of cross-reactivity. The next step was the integration of metabolomic approaches in the context of steroid analyses. As metabolomics tends to identify and quantify all the metabolites (i.e., the metabolome) in a specific system, appropriate strategies were proposed for discovering new biomarkers. Steroidomics, defined as the untargeted analysis of the steroid content in a sample, was implemented in several fields, including doping analysis, clinical studies, in vivo or in vitro toxicology assays, and more. This review discusses the current analytical methods for assessing steroid changes and compares them to steroidomics. Steroids, their pathways, their implications in diseases and the biological matrices in which they are analysed will first be described. Then, the different analytical strategies will be presented with a focus on their ability to obtain relevant information on the steroid pattern. The future technical requirements for improving steroid analysis will also be presented.

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The economical competitiveness of various power plant alternatives is compared. The comparison comprises merely electricity producing power plants. Combined heat and power (CHP) producing power will cover part of the future power deficit in Finland, but also condensing power plants for base load production will be needed. The following types of power plants are studied: nuclear power plant, combined cycle gas turbine plant, coal-fired condensing power plant, peat-fired condensing power plant, wood-fired condensing power plant and wind power plant. The calculations are carried out by using the annuity method with a real interest rate of 5 % per annum and with a fixed price level as of January 2008. With the annual peak load utilization time of 8000 hours (corresponding to a load factor of 91,3 %) the production costs would be for nuclear electricity 35,0 €/MWh, for gas based electricity 59,2 €/MWh and for coal based electricity 64,4 €/MWh, when using a price of 23 €/tonCO2 for the carbon dioxide emission trading. Without emission trading the production cost of gas electricity is 51,2 €/MWh and that of coal electricity 45,7 €/MWh and nuclear remains the same (35,0 €/MWh) In order to study the impact of changes in the input data, a sensitivity analysis has been carried out. It reveals that the advantage of the nuclear power is quite clear. E.g. the nuclear electricity is rather insensitive to the changes of nuclear fuel price, whereas for natural gas alternative the rising trend of gas price causes the greatest risk. Furthermore, increase of emission trading price improves the competitiveness of the nuclear alternative. The competitiveness and payback of the nuclear power investment is studied also as such by using various electricity market prices for determining the revenues generated by the investment. The profitability of the investment is excellent, if the market price of electricity is 50 €/MWh or more.

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Aim of this study was to investigate the means to reduce nutrient flows to water systems. Focus in this study was to examine peatland buffer zones as a solution to protect water bodies as well as to examine methane and nitrous oxide release from buffer zones. The literature survey covers a review of research which has been done till this day concerning the effects of forestry on water bodies. It also contains a review of the significance of forests and mires in hydrological cycle, effects of forestry on nutrient loads to water systems and a review of different solutions to diminish it. The solutions contain ditch shaping, submerged dams, sludge sumps, sedimentation ponds and buffer zones. The literature survey also covers nitrous oxide and methane gas emissions from buffer zones. Methane and nitrous oxide emissions from six different mires were studied during the summer of 2007. Measurements were conducted once a month using the static chamber method. Emissions of methane and nitrous oxide were calculated. Effects of water table level and peat temperature on emissions were also studied. The results showed a tendency to increased methane-emissions from natural peat lands when compared with restored buffer zones. The results showed also a tendency to increased CH4 emissions and decreased NO2 emissions with rising level of water table. Other mechanisms that influence emissions are vegetation composition and peat temperature. Considering the global warming as a result of increased greenhouse gas emissions, the emissions of CH4 and NO2 measured in the present study were not particularly high.

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Aim: We have previously documented the feasibility of neoadjuvant chemotherapy and EPP in a multicenter trial of MPM (Weder, Ann Oncol 18: 1196, 2007). The objectives of the trimodality trial SAKK17/04 (NCT00334594) were to evaluate the time to loco-regional relapse with or without high dose hemithoracic radiotherapy in a prospective multicenter randomized phase II trial in patients with R0 and R1 resection after neoadjuvant chemotherapy and EPP. Methods: Eligible patients had pathologically confirmed MPM, surgically resectable TNM stage (T1-3 N0-2 M0), PS0-1, ages 18-70 years. Part 1 had a phase II design, and included neoadjuvant chemotherapy with 3 cycles of cisplatin and pemetrexed, followed by restaging and EPP. The primary endpoint of part 1 was complete macroscopic resection (R0-1). Part 2 randomized consenting patients with R0-1 resection into two parallel phase II arms (control arm A and radiotherapy arm B). The primary endpoint for part 2 was loco-regional relapse-free survival (RFS). To detect a 1 year increase with 80% power and 10% alpha, 37 patients were needed for arm B. Secondary endpoints included operability, tolerability of chemotherapy and radiotherapy, survival, and translational research Results: Because accrual of part 2 was slower than planned, the trial was stopped in 2013. Overall, 153 patients entered the trial, of whom 125 underwent surgery and 99 had a complete macroscopic resection (primary endpoint part 1). Of the later patients, 54 could be randomized 1:1 into each arm. Reasons for non-randomization included patient refusal in 24 and ineligibility or protocol deviations in 21. Of the 27 patients randomized to hemithoracic radiotherapy, 25 completed the treatment as planned. For part 1 the median RFS was 8.8 (95%CI: 7.3-10.7) and median OS was 15.0 (95% CI: 12.1-19.3) months. For part 2 the median local RFS for group A was 7.6 (95%CI: 5.5-10.7) and for group B 9.4 (95%CI: 6.5-11.9) months (primary endpoint part 2), while the overall RFS and OS for group A were 5.7 (95%CI: 3.5-8.8) and 16.9 (95%CI: 10.7-23.6) months and for group B 7.6 (95% CI:5.2-10.6) and 14.9 (95%CI: 7.0-17.6) months. Conclusions: This study did not reach the primary endpoint which was defined as one-year increase in loco-regional relapse-free survival and thus does not support the routine use of hemithoracic RT after neoadjuvant chemotherapy and EPP. Disclosure: All authors have declared no conflicts of interest.