994 resultados para Flatness deviation


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Pysyäkseen kilpailukykyisenä vapautuneilla sähkömarkkinoilla on voimalaitoksen energiantuotantokustannusten oltava mahdollisimman matalia, tinkimättä kuitenkaan korkeasta käytettävyydestä. Polttoaineen energiasisällön mahdollisimman hyvä hyödyntäminen on ratkaisevan tärkeää voimalaitoksen kannattavuudelle. Polttoainekustannusten osuus on konvektiivisilla laitoksilla yleensä yli puolet koko elinjakson kustannuksista. Kun vielä päästörajat tiukkenevat koko ajan, korostuu polttoaineen korkea hyötykäyttö entisestään. Korkea energiantuotannon luotettavuus ja käytettävyys ovat myös elintärkeitä pyrittäessä kustannusten minimointiin. Tässä työssä on käyty läpi voimalaitoksen kustannuksiin vaikuttavia käsitteitä, kuten hyötysuhdetta, käytettävyyttä, polttoaineen hintoja, ylös- ja alasajoja ja tärkeimpiä häviöitä. Ajostrategiassa ja poikkeamien hallinnassa pyritään hyvään hyötysuhteeseen ja alhaisiin päästöihin joka käyttötilanteessa. Lisäksi on tarkasteltu tiettyjen suureiden, eli höyryn lämpötilan ja paineen, savukaasun hapen pitoisuuden, savukaasun loppulämpötilan, sekä lauhduttimen paineen poikkeamien vaikutusta ohjearvostaan energiantuotantokustannuksiin. Happi / hiilimonoksidi optimoinnissa on otettu huomioon myös pohjatuhkan palamattomat.

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Abstract Background: To evaluate the predictability of refraction following immediate sequential bilateral cataract surgery (ISBCS) performed under general anaesthesia. Methods: This is a retrospective review of all ISBCS performed at Kantonsspital Winterthur, Switzerland, between April 2000 and September 2013. The case notes of 250 patients were reviewed. Patients having full refraction reported (110 patients/220 eyes) were included. 210 (95 %) eyes had a straight forward phacoemulsification with posterior chamber intraocular lens implantation, seven eyes had a planned extracapsular cataract extraction (ECCE); three eyes had an intracapsular cataract extraction. Results: Both eyes of 110 patients (64 women, 46 men) with a mean age of 79.0 years, standard deviation (SD) ±11.4 (range 26 to 97 years) were included. Median preoperative best corrected visual acuity (BCVA) was 0.5 LogMAR in the first eye, the interquartile range (IQR) was [0.4, 1.2]; 0.7 LogMAR in the second eye with IQR [0.4, 1.8]. At one month, the median BCVA was 0.2 LogMAR, IQR [0.1, 0.3] in the first eye, median BCVA was 0.1 LogMAR and IQR [0.0, 0.5] in the second eye. There were 3 eyes (3 %) that lost 3 lines or more in BCVA at one month (control vs. pre-operatively). In all three cases, poor visual acuity had been recorded pre-operatively (>1 LogMAR). Achieved refraction was within ±1.0 D of the target in 83 % of eyes. There were only 5 % (n = 6) of cases where if delayed sequential bilateral extraction had been performed could potentially intraocular lens (IOL) choice have been adjusted, in four of these cases, target refraction was within ±1.0 D in the second eye. Conclusions: ISBCS performed under general anaesthesia achieves target refraction in 83 % of eyes after consideration of complications, ocular co-morbidities and systemic restrictions. In the majority of cases where IOL power calculation could be considered, the achieved refraction of the second surgical eye was within ±1.0 D of intended refraction. This undermines the utility of IOL power adjustments in the second surgical eye. Keywords: Cataract, Cataract surgery, Immediate sequential bilateral cataract surgery

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Työssä verrattiin perälaatikoilla 1 ja 2 valmistettujen papereiden rakenteellisia ominaisuuksia. Paperin rakenteessa formaatio oli tärkein ominaisuus ja sen jälkeen kuituorientaatio. Näytteiden valintaperusteena pidettiin sitä, että vertailtavilla näytteillä formaatio (pohja) oli paras kyseisellä perälaatikolla ja vetolujuussuhteet olivat samoja. Toinen valintatapa oli verrata samoissa virtausolosuhteissa valmistettuja papereita keskenään. Näytteiden formaatio mitattiin betaradiografialla. Fosforikuvalevystä skannattu kuva analysoitiin kuva-analyysillä. Mittauksen etuna oli suuri erottelukyky, joka mahdollisti monipuolisen tunnuslukujen laskennan. Näistä esimerkkeinä olivat keskihajonta, vinous ja huipukkuus. Lisäksi määritettiin flokkikokojakaumat sekä kone- että poikkisuuntaan. Kuituorientaation määrityksessä paperinäyte revittiin kerroksiin, kerrokset skannattiin ja kuvat analysoitiin kuvankäsittelyohjelmilla. Juova- ja kuituorientaatioanalyysissä määritettiin orientaatiokulma, max/min-arvo ja anisotropia. Virtaviiva-analyysin tunnusluku oli pyörrekoko. Käytettäessä tunnuslukuna variaatiokerrointa formaatio oli parempi perälaatikolla 1 ali- ja yliperällä. Tasaperän läheisyydessä formaatio oli huonompi. Keskihajonta oli pienempi perälaatikolla 1, mutta erot perälaatikoiden välillä tasaantuivat lähellä tasaperää. Flokkikoko oli koko s/v-alueella hieman suurempi perälaatikolla 1. Virtaviiva-analyysin avulla saatiin selville, että perälaatikolla 1 valmistettujen papereiden paikallinen orientaatiovaihtelu ja pintojen toispuoleisuus oli lievempää kuin perälaatikolla 2.

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Tutkimuksen tavoitteena on selvittää analyytikoiden ennustevirheiden suuruus sekä jakauma. Keskeisenä tavoitteena on selvittää, kuinka paljon yrityksen toimiala ja markkina-arvo vaikuttavat ennustevirheen suuruuteen ja tätä kautta vääristävät osakkeiden hinnoittelua. Tutkimus olettaa, että osakkeiden hinnoittelu perustuu tuotto-odotuksiin eli analyytikoiden tulosennusteisiin sekä riskiin. Tutkimuksessa on käytetty kvantitatiivisia menetelmiä. Tutkimusaineistona on käytetty Helsingin pörssin päälistalla vuosina 1998 – 1999 olleita yrityksiä, joille on annettu tulosennusteita. Tulosennusteet on poimittu manuaalisesti REUTTERS:in tietokannasta. Tulosennusteet vuosille 1998 - 1999 eivät ole selvästi positiivisia tai negatiivisia. Ennustevirheet eivät myöskään ole jakautuneet selvästi toimialan mukaan. Kuitenkin vuonna 1999 ”teollisuus” sekä ”palvelut” toimialoille annettiin selvästi liian pessimistisiä ennusteita. Myöskään yhtiön markkina-arvolla ei ole selvää yhteyttä ennustevirheen suuruuteen. Kuitenkin vuonna 1999 isojen yhtiöiden tuloksista on annettu liian pessimistisiä ja pienten liian positiivisia arvioita. Etsittäessä ennustevirheen selittäjiä regressioanalyysin avulla, vahvimmiksi selittäjiksi nousivat analyytikoiden määrä per yhtiö ja analyytikkoennusteiden keskihajonta. Selittäjät saavuttivat 40 prosentin selitysasteen.

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OBJECTIVE: To identify risk factors, circumstances, and outcomes for individuals with acute ischemic stroke (AIS) chameleons (AIS-C) arriving in the emergency department of a university hospital. METHODS: We retrospectively reviewed all patients with AIS from the prospectively constructed Acute Stroke Registry and Analysis of Lausanne during 8.25 years. AIS-C were defined as a failure to suspect stroke or as incorrect exclusion of stroke diagnosis. They were compared with patients diagnosed correctly at the time of admission. RESULTS: Forty-seven of 2,200 AIS were missed (2.1%). These AIS-C were either very mild or very severe strokes. Multivariate analysis showed a younger age in patients with AIS-C (odds ratio [OR] per year 0.98, p < 0.01), less prestroke statin treatment (OR 0.29, p = 0.04), and lower diastolic admission blood pressure (OR 0.98 p = 0.04). They showed less eye deviation (OR 0.21, p = 0.04) and more cerebellar strokes (OR 3.78, p < 0.01). AIS-C were misdiagnosed as other neurologic (42.6% of cases) or nonneurologic (17.0%) disease, as unexplained decreased level of consciousness (21.3%), and as concomitantly present disease (19.1%). At 12 months, patients with AIS-C had less favorable outcomes (adjusted OR 0.21, p < 0.01) and higher mortality (adjusted OR 4.37, p < 0.01). CONCLUSIONS: AIS are missed in patients with younger age with a lower cerebrovascular risk profile and may be masked by other acute conditions. Patients with chameleons present more often with milder strokes or coma, fewer focal signs and cerebellar strokes, and have higher disability and mortality rates at 12 months. These findings may be used to raise awareness in emergency departments to recognize and treat such patients appropriately.

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The semiclassical Wigner-Kirkwood ̄h expansion method is used to calculate shell corrections for spherical and deformed nuclei. The expansion is carried out up to fourth order in ̄h. A systematic study of Wigner-Kirkwood averaged energies is presented as a function of the deformation degrees of freedom. The shell corrections, along with the pairing energies obtained by using the Lipkin-Nogami scheme, are used in the microscopic-macroscopic approach to calculate binding energies. The macroscopic part is obtained from a liquid drop formula with six adjustable parameters. Considering a set of 367 spherical nuclei, the liquid drop parameters are adjusted to reproduce the experimental binding energies, which yields a root mean square (rms) deviation of 630 keV. It is shown that the proposed approach is indeed promising for the prediction of nuclear masses.

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Contralesional brain connectivity plasticity was previously reported after stroke. This study aims at disentangling the biological mechanisms underlying connectivity plasticity in the uninjured motor network after an ischemic lesion. In particular, we measured generalized fractional anisotropy (GFA) and magnetization transfer ratio (MTR) to assess whether poststroke connectivity remodeling depends on axonal and/or myelin changes. Diffusion-spectrum imaging and magnetization transfer MRI at 3T were performed in 10 patients in acute phase, at 1 and 6 months after stroke, which was affecting motor cortical and/or subcortical areas. Ten age- and gender-matched healthy volunteers were scanned 1 month apart for longitudinal comparison. Clinical assessment was also performed in patients prior to magnetic resonance imaging (MRI). In the contralesional hemisphere, average measures and tract-based quantitative analysis of GFA and MTR were performed to assess axonal integrity and myelination along motor connections as well as their variations in time. Mean and tract-based measures of MTR and GFA showed significant changes in a number of contralesional motor connections, confirming both axonal and myelin plasticity in our cohort of patients. Moreover, density-derived features (peak height, standard deviation, and skewness) of GFA and MTR along the tracts showed additional correlation with clinical scores than mean values. These findings reveal the interplay between contralateral myelin and axonal remodeling after stroke.

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The goal of this study was to investigate the performance of 3D synchrotron differential phase contrast (DPC) imaging for the visualization of both macroscopic and microscopic aspects of atherosclerosis in the mouse vasculature ex vivo. The hearts and aortas of 2 atherosclerotic and 2 wild-type control mice were scanned with DPC imaging with an isotropic resolution of 15 μm. The coronary artery vessel walls were segmented in the DPC datasets to assess their thickness, and histological staining was performed at the level of atherosclerotic plaques. The DPC imaging allowed for the visualization of complex structures such as the coronary arteries and their branches, the thin fibrous cap of atherosclerotic plaques as well as the chordae tendineae. The coronary vessel wall thickness ranged from 37.4 ± 5.6 μm in proximal coronary arteries to 13.6 ± 3.3 μm in distal branches. No consistent differences in coronary vessel wall thickness were detected between the wild-type and atherosclerotic hearts in this proof-of-concept study, although the standard deviation in the atherosclerotic mice was higher in most segments, consistent with the observation of occasional focal vessel wall thickening. Overall, DPC imaging of the cardiovascular system of the mice allowed for a simultaneous detailed 3D morphological assessment of both large structures and microscopic details.

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OBJECTIVE: White coat hypertensive is a pre-hypertensive state that has been associated with increased sympathetic drive. The objective of the study was to compare the exposure of the kidney to sympathetic nerve activity using urinary normetanephrine (UNMN) as a marker of renal sympathetic exposure in white coat hypertensive (WCH) and healthy normotensive (HN) participants. DESIGN AND METHOD: This was a double-blind randomized placebo-controlled crossover study. WCH were included if office blood pressure was >140/80 mmHg and ambulatory blood pressure <135/85 mmHg and HN if OBP was <140/90 mmHg and ABP <135/85 mmHg Participants were randomized to receive either 16 mg of candesartan or a matched placebo for one week before study day. On the study day systemic and renal hemodynamics as well as plasma norepinephrine and urinary excretion of normetanephrine (measured by LC/MS-MS were measured after one hour of baseline, one hour of lower body negative pressure and one hour of recovery period. Excretion of UNMN was expressed as the total of UNMN excreted during these three hours (cumUNMN). Paired or unpaired t-test were used for comparison. RESULTS: 25 HN and 12 WCH participants were included in the study. Mean age (±standard deviation), BMI were respectively 31.0±10.5 years and 22.0 ± 2.2 Kg/m2 in HN and 40.7±17.8 years and 26.7 ± 6.3 Kg/m2 in WCH.Table 1 Baseline mean blood pressure, plasma noradrenaline and cumulated UNMN during placebo and candesartan(Figure is included in full-text article.)Mean blood pressure was higher during placebo and candesartan in WCH compared to HN. Cumulated UNMN was higher in both groups after candesartan treatment. Cumulated UNMN was higher in WCH than in HN only after candesartan treatment. CONCLUSIONS: Urinary excretion of normetanephrine is increased in WCH compared to HN when treated with candesartan. The increased excretion of uNMN when the renin angiotensin system is blocked might reflect an increased sensitivity of WCH to stress conditions such as orthostatic stress.

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Background Most of the proteins in the Protein Data Bank (PDB) are oligomeric complexes consisting of two or more subunits that associate by rotational or helical symmetries. Despite the myriad of superimposition tools in the literature, we could not find any able to account for rotational symmetry and display the graphical results in the web browser. Results BioSuper is a free web server that superimposes and calculates the root mean square deviation (RMSD) of protein complexes displaying rotational symmetry. To the best of our knowledge, BioSuper is the first tool of its kind that provides immediate interactive visualization of the graphical results in the browser, biomolecule generator capabilities, different levels of atom selection, sequence-dependent and structure-based superimposition types, and is the only web tool that takes into account the equivalence of atoms in side chains displaying symmetry ambiguity. BioSuper uses ICM program functionality as a core for the superimpositions and displays the results as text, HTML tables and 3D interactive molecular objects that can be visualized in the browser or in Android and iOS platforms with a free plugin. Conclusions BioSuper is a fast and functional tool that allows for pairwise superimposition of proteins and assemblies displaying rotational symmetry. The web server was created after our own frustration when attempting to superimpose flexible oligomers. We strongly believe that its user-friendly and functional design will be of great interest for structural and computational biologists who need to superimpose oligomeric proteins (or any protein). BioSuper web server is freely available to all users at http://ablab.ucsd.edu/BioSuper webcite.

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The time required to image large samples is an important limiting factor in SPM-based systems. In multiprobe setups, especially when working with biological samples, this drawback can make impossible to conduct certain experiments. In this work, we present a feedfordward controller based on bang-bang and adaptive controls. The controls are based in the difference between the maximum speeds that can be used for imaging depending on the flatness of the sample zone. Topographic images of Escherichia coli bacteria samples were acquired using the implemented controllers. Results show that to go faster in the flat zones, rather than using a constant scanning speed for the whole image, speeds up the imaging process of large samples by up to a 4x factor.

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[SPA] OBJETIVO: El artículo presenta los resultados obtenidos en la investigación que dio origen a la tesis doctoral defendida por la autora en la Universitat de Lleida (España), cuyo objetivo fue identificar las Competencias Profesionales de los nutricionistas que trabajan en el ámbito de la Nutrición Deportiva. MÉTODOS: Fueron investigados 14 expertos provenientes de Australia (n=1), Brasil (n=7), España (n=3) y Estados Unidos (n=3). La herramienta metodológica utilizada fue la técnica Delphi, compuesta de tres rondas de cuestionarios. En la primera ronda los expertos proporcionaron, a través de sus discursos, la identificación de un listado de Competencias Profesionales, información que en la segunda y tercera ronda pudieron ser evaluadas y posteriormente analizadas a través de cálculos estadísticos descriptivos (media, moda, mediana y desviación Standard). RESULTADOS: De esta manera, se llegó al consenso entre los expertos sobre 147 competencias profesionales identificadas. Las competencias fueron clasificadas en cuatro macro categorías de Competencias Profesionales: Competencias Técnicas (38), Metodológicas (62), Participativas (24) y Personales (23). CONCLUSIÓN: Los resultados demostraron que el estudio sistematizado de las Competencias Profesionales del Nutricionista Deportivo contribuye para el establecimiento de los contenidos que deben componer la disciplina de Nutrición Deportiva a ser incorporada en los itinerarios curriculares de las carreras de Nutrición Humana y Dietética.

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The purpose of this study was to evaluate the competence of nurse teachers, who are teaching nursing at polytechnic level in Finland. The following research questions were framed for the study: What kind of evaluation nurse teachers of their nursing competence, teaching skills, evaluation skills, personality factors and relationships with students. The data were collected by a questionnaire (A Tool for Evaluation of Requirements of Nurse Teacher, ERNT). The questionnaire regarded background factors and 20 statements divided in five categories. The five competence categories were: Nursing competence, Teaching skills, Evaluation skills, Personality factors and Relationships with students. The evaluation scale was a 5-point Likert-scale. The respondents were nurse teachers, teacher for emergency nursing, public health nurse and midwifery teachers from all polytechnics in Finland. Response rate to the questionnaire was 46 % (n=342). The data were analysed by using descriptive statistics. Mean scores and standard deviations for each item were calculated. Category scores were obtained by summing scores of all items within a category. The results of this study showed that nurse teacher evaluated their competence on a high level. Concerning the category Relationships with students (mean 4.61, standard deviation 0.71) they got the highest averages. The lowest scores were gained regarding the requirements associated with teaching skills (mean 4.30, standard deviation 0.82). Concerning a single question, the best score was achieved in ability to take students seriously (mean 4.66, standard deviation 0.71) and the lowest score was achieved for their guidance of students to advance in decision making (mean 4.15, Std 0.69). The nurse teachers evaluated themselves with relatively high scores concerning competence categories as a hole. In future it is important to study nurse teacher competence with students or authorities of health service.

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Pain is defined as an unpleasant sensory or emotional experience, associated with tissue damage, that is a reality linked to the surgical procedure and the postoperative period. Objective: Knowing the degree of pain experienced by patients after cardiac surgery, depending on the type of intervention they underwent, over the post-operative period in an intensive care unit (ICU). Method: Descriptive observational study. Pain was assessed by the visual analog scale (VAS), going from 0 to 10, thereby obtaining the first VAS1 assessment at 2 h post-extubation and every 8 hours thereafter up to 48 hours or until discharge to floor VAS7. It included patients having undergone cardiac surgery [valve surgery, bypass, combined procedure (including valve surgery and bypass) and mediastinitis]. Data were processed using Spss.v 20. Results: 120 patients 70 years old on average (standard deviation (SD): 13.3 years old) were included, out of which 70% were male. 40.8% of them had underwent bypass coronary revascularization. Patients subjected to the bypass technique showed an VAS1 mean value of 4.35 (SD: 2.45), unlike those subjected to valve surgery, who showed a mean value of 2.89 (SD: 2.27), those subjected to the combined procedure, who showed a mean value of 3.87 (SD: 2.90), and those with mediastinitis, who showed a mean value of 3.33 (SD: 3.51); (p < 0.031). 28.5% of patients had underwent revascularization (n = 49 ) by an internal mam mary artery (IMA) graft. These patients showed a mean value for VAS1 of 5.4 (SD: 1.89), unlike those who had underwent a combined procedure [IMA and saphenous vein (SV)], who showed a mean value of 3.9 (SD: 2.6), and those who had underwent a SV procedure , who showed a mean value of 3.5 (SD: 2.1); (p < 0.045). Conclusions: Patients having underwent bypass and IMA procedures perceive more pain than in other cardiac surgery and graft interventions

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This chapter presents possible uses and examples of Monte Carlo methods for the evaluation of uncertainties in the field of radionuclide metrology. The method is already well documented in GUM supplement 1, but here we present a more restrictive approach, where the quantities of interest calculated by the Monte Carlo method are estimators of the expectation and standard deviation of the measurand, and the Monte Carlo method is used to propagate the uncertainties of the input parameters through the measurement model. This approach is illustrated by an example of the activity calibration of a 103Pd source by liquid scintillation counting and the calculation of a linear regression on experimental data points. An electronic supplement presents some algorithms which may be used to generate random numbers with various statistical distributions, for the implementation of this Monte Carlo calculation method.