958 resultados para refined multiscale entropy


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Background: As the long-term efficacy of stereotactic body radiation therapy (SBRT) becomes established and other prostate cancer treatment approaches are refined and improved, examination of quality of life (QOL) following prostate cancer treatment is critical in driving both patient and clinical treatment decisions. We present the first study to compare QOL after SBRT and radical prostatectomy, with QOL assessed at approximately the same times pre- and post-treatment and using the same validated QOL instrument. Methods: Patients with clinically localized prostate cancer were treated with either radical prostatectomy (n = 123 Spanish patients) or SBRT (n = 216 American patients). QOL was assessed using the Expanded Prostate Cancer Index Composite (EPIC) grouped into urinary, sexual, and bowel domains. For comparison purposes, SBRT EPIC data at baseline, 3 weeks, 5, 11, 24, and 36 months were compared to surgery data at baseline, 1, 6, 12, 24,and 36 months. Differences in patient characteristics between the two groups were assessed using Chi-squared tests for categorical variables and t-tests for continuous variables. Generalized estimating equation (GEE) models were constructed for each EPIC scale to account for correlation among repeated measures and used to assess the effect of treatment on QOL. Results: The largest differences in QOL occurred in the first 1-6 months after treatment, with larger declines following surgery in urinary and sexual QOL as compared to SBRT, and a larger decline in bowel QOL following SBRT as compared to surgery. Long-term urinary and sexual QOL declines remained clinically significantly lower for surgery patients but not for SBRT patients. Conclusions: Overall, these results may have implications for patient and physician clinical decision making which are often influenced by QOL. These differences in sexual, urinary and bowel QOL should be closely considered in selecting the right treatment, especially in evaluating the value of non-invasive treatments, such as SBRT.

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Puupelletti on puumurskeesta puristamalla valmistettu polttoainejaloste, jonka raaka- aineita ovat mekaanisen metsäteollisuuden sivutuotteet kutterinlastu ja sahanpuru. Sylinterin muotoiset pelletit ovat yleensä halkaisijaltaan 6-10 mm ja pituudeltaan 10 - 30 mm. Tässä diplomityössä tarkastellaan pellettiketjua valmistuksesta loppukäyttöön. Työ sisältää valmistuksen, kuljetuksen ja käytön niin tekniset puolet, kuin taloudelliset näkökohdatkin. Myös muiden maiden pellettimarkkinoiden tilanne tuodaan esille. Työn lopussa kuvataan muutama case-esimerkki onnistuneista pellettiketjuista. Suomessa puupellettimarkkinoiden kehitys alkoi 1998 Vöyrissä auenneen pellettitehtaan myötä. Pellettien tuotanto ja kulutus ovat sen jälkeen kasvaneet nopeasti ja nyt vuonna 2001 pellettien tuotantokapasiteetti on 150 000 t/a. Pellettimarkkinoiden nopea kehitys Suomessa perustuu öljyn korkeaan hintaan, käytön helppouteen ja ympäristöystävällisyyteen. Käyttölaitteistojen yleistyessä ja jakelun tehostuessa pellettiliiketoiminta tulee vahvistamaan asemaansa entisestään Suomessa

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Työn tavoitteena oli optimoida LWC-paperitehtaan kahden hiomolinjan rejektinkäsittelyt. Uusituilla rejektilinjoilla on käytössä keskisakeusrejektinjauhatus. Työn keskeinen osa oli teräkoeajot, teräsarjoja tutkittiin kuusi, kolme molemmilla linjoilla. Kahdessa ensimmäisessä teräkoeajossa oli molemmilla linjoilla samanlaiset jauhinterät. Teräkoeajojen tuloksista havaittiin yleisellä tasolla, että suurin osa mitatuista ominaisuuksista parani jauhatusastetta nostettaessa. Ainoastaan repäisylujuus heikkeni. Terävaihtoehdoista pystyttiin poimimaan molemmille linjoille sopiva terävaihtoehto. Rejektinlajittelun havaittiin parantavan edelleen massan laatuominaisuuksia, paitsi repäisylujuutta. Toisena osuutena vertailtiin keskisakeusjauhimen terävaihtoehtoa, jolla saavutettiin hyviä tuloksia, toisen paperitehtaan korkeassa sakeudessa jauhettuun rejektiin. Korkeasakeusjauhimen terää ei erityisesti valikoitu koeajoa varten. Tuloksista havaittiin, että keskisakeusjauhimella saadaan aikaan varsin hyvää LWC-paperiin käytettävää massaa. Keskisakeudessa jauhettu massa oli monilta ominaisuuksiltaan jopa parempaa kuin korkeasakeusjauhimen massa. Työn kolmannessa osuudessa ajettiin rejektilinjalla sakeuskoeajo. Sakeuskoeajosta havaittiin, että optiset ominaisuudet olivat parhaimmillaan jauhimen MC-sakeusalueen keskivaiheilla. Jauhatussakeuden noustessa kuidut jäivät jäykemmiksi ja karkeammiksi. Tikkupitoisuus oli sitä pienempi, mitä alhaisempaa jauhatussakeutta käytettiin. Sakeudella ei ollut selvää vaikutusta lujuusominaisuuksiin. Tulosten perusteella paras jauhatussakeus keskisakeusjauhimella oli sakeusalueen puoliväli. Työn viimeisenä osana selvitettiin miten kytkentämuutos, jossa rejektilinjan viimeisen lajittimen rejekti käännettiin palaamaan jälkilajittelun sijaan rejektilinjan kaariseulalle, vaikutti koko hiomon kapasiteettiin ja rejektilinjan massan laatuun. Koeajojen tuloksena havaittiin, että kytkentämuutolla pystyttiin nostamaan koko hiomon kapasiteettia ja rejektilinjan akseptin laatu parani.

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Maximum entropy modeling (Maxent) is a widely used algorithm for predicting species distributions across space and time. Properly assessing the uncertainty in such predictions is non-trivial and requires validation with independent datasets. Notably, model complexity (number of model parameters) remains a major concern in relation to overfitting and, hence, transferability of Maxent models. An emerging approach is to validate the cross-temporal transferability of model predictions using paleoecological data. In this study, we assess the effect of model complexity on the performance of Maxent projections across time using two European plant species (Alnus giutinosa (L.) Gaertn. and Corylus avellana L) with an extensive late Quaternary fossil record in Spain as a study case. We fit 110 models with different levels of complexity under present time and tested model performance using AUC (area under the receiver operating characteristic curve) and AlCc (corrected Akaike Information Criterion) through the standard procedure of randomly partitioning current occurrence data. We then compared these results to an independent validation by projecting the models to mid-Holocene (6000 years before present) climatic conditions in Spain to assess their ability to predict fossil pollen presence-absence and abundance. We find that calibrating Maxent models with default settings result in the generation of overly complex models. While model performance increased with model complexity when predicting current distributions, it was higher with intermediate complexity when predicting mid-Holocene distributions. Hence, models of intermediate complexity resulted in the best trade-off to predict species distributions across time. Reliable temporal model transferability is especially relevant for forecasting species distributions under future climate change. Consequently, species-specific model tuning should be used to find the best modeling settings to control for complexity, notably with paleoecological data to independently validate model projections. For cross-temporal projections of species distributions for which paleoecological data is not available, models of intermediate complexity should be selected.

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The local thermodynamics of a system with long-range interactions in d dimensions is studied using the mean-field approximation. Long-range interactions are introduced through pair interaction potentials that decay as a power law in the interparticle distance. We compute the local entropy, Helmholtz free energy, and grand potential per particle in the microcanonical, canonical, and grand canonical ensembles, respectively. From the local entropy per particle we obtain the local equation of state of the system by using the condition of local thermodynamic equilibrium. This local equation of state has the form of the ideal gas equation of state, but with the density depending on the potential characterizing long-range interactions. By volume integration of the relation between the different thermodynamic potentials at the local level, we find the corresponding equation satisfied by the potentials at the global level. It is shown that the potential energy enters as a thermodynamic variable that modifies the global thermodynamic potentials. As a result, we find a generalized Gibbs-Duhem equation that relates the potential energy to the temperature, pressure, and chemical potential. For the marginal case where the power of the decaying interaction potential is equal to the dimension of the space, the usual Gibbs-Duhem equation is recovered. As examples of the application of this equation, we consider spatially uniform interaction potentials and the self-gravitating gas. We also point out a close relationship with the thermodynamics of small systems.

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Morphogenesis emerges from complex multiscale interactions between genetic and mechanical processes. To understand these processes, the evolution of cell shape, proliferation and gene expression must be quantified. This quantification is usually performed either in full 3D, which is computationally expensive and technically challenging, or on 2D planar projections, which introduces geometrical artifacts on highly curved organs. Here we present MorphoGraphX ( www.MorphoGraphX.org), a software that bridges this gap by working directly with curved surface images extracted from 3D data. In addition to traditional 3D image analysis, we have developed algorithms to operate on curved surfaces, such as cell segmentation, lineage tracking and fluorescence signal quantification. The software's modular design makes it easy to include existing libraries, or to implement new algorithms. Cell geometries extracted with MorphoGraphX can be exported and used as templates for simulation models, providing a powerful platform to investigate the interactions between shape, genes and growth.

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Diplomityön keskeisenä tavoitteena oli selvittää painehiomon tuotantokapasiteetin lisäyksen vaikutus painehiokkeen laatuominaisuuksiin. Tarkasteltavina painehiomon tuotanto-kapasiteettiin vaikuttavina tekijöinä olivat painehiomakoneen suihkuveden lämpötilan lasku sekä uuden rejektijauhimen käyttöönotto. Painehiomakoneen suihkuveden lämpötilan lasku 95 ºC:sta 70 ºC:een toteutettiin kahden viikon mittaisena koeajona. Tarkoituksena oli selvittää painehiontaprosessissa ja painehiokkeen sekä paperin laadussa tapahtuva muutos. PGW70-koeajolla saavutettiin mahdollisuus nostaa tuotantonopeutta hiomakivillä silti kuormittamatta liiaksi lajittelua ja rejektinkäsittelyä. Tarkasteltaessa painehiokkeen laatua PGW70-koeajossa kiteytyi tapahtunut laatumuutos lyhentyneestä kuidun pituudesta aiheutu-neeksi. Havaittiin, että alentamalla hiontalämpötilaa on mahdollista saavuttaa paremmat painehiokkeen pinta- ja optiset ominaisuudet lujuusominaisuuksien heiketessä hieman. Rejektijauhimen käyttöönottoon liittyvien tarkasteluiden tavoitteena oli selvittää uuden rejektijauhimen käyttöönoton myötä painehiokkeessa mahdollisesti tapahtuva laatumuutos. Lisäksi haluttiin tarkastella jauhetun rejektin laatuominaisuuksia rejektijauhimen energian ominaiskulutuksen eri tasoilla ja mahdollisuutta siirtää kuidutuksen painopistettä hiomakiviltä rejektijauhatukseen nostamalla kivenalusfreenestä. Varsinaisessa rejektijauhimen käyttöönottovaiheessa ei painehiokkeen laatumuutosta ollut havaittavissa. Rejektijauhimen kuormituskoeajossa ajettiin rejektijauhimella 2 koesarjaa, matalalla ja korkealla kivenalusfreeneksellä, kasvattaen rejektijauhimen EOK:a. Lisä-muuttujaksi koeajossa muodostui tahattomasti jauhatussakeus. Koejossa paras kuidun muokkau-tuvuus saavutettiin alhaisemmalla kivenalusfreeneksellä (130-140 ml) ja jauhatussakeudella (alle 40 %) korkeimmalla saavutetulla EOK:lla eli 0,80 MWh/t. Korkealla kivenalusfreeneksellä ja jauhatussakeudella tapahtunut jauhatus osoittautui kuituja katkovaksi. Karkeaan painehiokerejektiin tulisi kohdistaa huomattavasti enemmän jauhatusenergiaa kuin koeajossa oli mahdollista. Ongelmaksi siis muodostui rejektijauhimen heikko kuormitettavuus, jota tulee parantaa esimerkiksi terävalinnoin.

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Diplomityö käsittelee nostopuomin hitsauksen ja koneistuksen kehittämistä alihankinta-konepajassa. Työn tavoitteena on nostopuomin valmistuksen tehostaminen. Työssä kes-kitytään hitsauksen osalta tuotantolayoutin kehittämiseen, kaariaikasuhteen parantami-seen sekä hitsausmuodonmuutosten ehkäisyyn ja ennakointiin. Koneistuksessa keskity-tään tuotantolayoutin kehittämiseen sekä kappaleen kiinnittämiseen ja työkaluvalintoi-hin. Työn teoriaosa käsittelee hitsauksen ja koneistuksen seikkoja, jotka vaikuttavat valmis-tuksen tehokkuuteen. Lisäksi teoriaosassa perehdytään tuotantomuotoihin, tuotantojär-jestelmiin ja tuotannonohjaukseen. Käytännön osuudessa käsitellään niitä valmistuksen tehostamiskeinoja, jotka soveltuvat metsäkoneen nostopuomien sarjatuotantoon Jormet Oy:ssä. Työssä esitellään valmistuksen työvaiheet sekä selvitetään tuotannon ongelmakohdat ja pullonkaulat. Ongelmana tuotannossa on suuri jalostamattoman työn osuus, joka koos-tuu siirroista, nostoista, muodonmuutosten oikomisesta sekä koneistuksessa puomin kiinnittämisestä ja irrottamisesta. Layout muutokset, hitsauskiinnittimien ja pyörityslaitteiden kehittäminen sekä töiden ohjeistus nostavat kaariaikasuhdetta ja lyhentävät hitsausaikaa. Koneistuksessa layoutin ja kiinnittimen kehittäminen vähentävät jalostamattoman työn osuutta parantaen samalla koneistuksen tehokkuutta. Lastuamistehokkuus paranee oikeiden työkalu- ja parametri-valintojen avulla.

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Olive oil decreases the risk of CVD. This effect may be due to the fatty acid profile of the oil, but it may also be due to its antioxidant content which differs depending on the type of olive oil. In this study, the concentrations of oleic acid and antioxidants (phenolic compounds and vitamin E) in plasma and LDL were compared after consumption of three similar olive oils, but with differences in their phenolic content. Thirty healthy volunteers participated in a placebo-controlled, double-blind, crossover, randomized supplementation trial. Virgin, common, and refined olive oils were administered during three periods of 3 weeks separated by a 2-week washout period. Participants were requested to ingest a daily dose of 25 ml raw olive oil, distributed over the three meals of the day, during intervention periods. All three olive oils caused an increase in plasma and LDL oleic acid (P,0·05) content. Olive oils rich in phenolic compounds led to an increase in phenolic compounds in LDL (P,0·005). The concentration of phenolic compounds in LDL was directly correlated with the phenolic concentration in the olive oils. The increase in the phenolic content of LDL could account for the increase of the resistance of LDL to oxidation, and the decrease of the in vivo oxidized LDL, observed in the frame of this trial. Our results support the hypothesis that a daily intake of virgin olive oil promotes protective LDL changes ahead of its oxidation.

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In this paper we explore the use of non-linear transformations in order to improve the performance of an entropy based voice activity detector (VAD). The idea of using a non-linear transformation comes from some previous work done in speech linear prediction (LPC) field based in source separation techniques, where the score function was added into the classical equations in order to take into account the real distribution of the signal. We explore the possibility of estimating the entropy of frames after calculating its score function, instead of using original frames. We observe that if signal is clean, estimated entropy is essentially the same; but if signal is noisy transformed frames (with score function) are able to give different entropy if the frame is voiced against unvoiced ones. Experimental results show that this fact permits to detect voice activity under high noise, where simple entropy method fails.

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In recent years, massive protostars have turned out to be a possible population of high-energy emitters. Among the best candidates is IRAS 16547-4247, a protostar that presents a powerful outflow with clear signatures of interaction with its environment. This source has been revealed to be a potential high-energy source because it displays non-thermal radio emission of synchrotron origin, which is evidence of relativistic particles. To improve our understanding of IRAS 16547-4247 as a high-energy source, we analyzed XMM-Newton archival data and found that IRAS 16547-4247 is a hard X-ray source. We discuss these results in the context of a refined one-zone model and previous radio observations. From our study we find that it may be difficult to explain the X-ray emission as non-thermal radiation coming from the interaction region, but it might be produced by thermal Bremsstrahlung (plus photo-electric absorption) by a fast shock at the jet end. In the high-energy range, the source might be detectable by the present generation of Cherenkov telescopes, and may eventually be detected by Fermi in the GeV range.

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We present a detailed evaluation of the seasonal performance of the Community Multiscale Air Quality (CMAQ) modelling system and the PSU/NCAR meteorological model coupled to a new Numerical Emission Model for Air Quality (MNEQA). The combined system simulates air quality at a fine resolution (3 km as horizontal resolution and 1 h as temporal resolution) in north-eastern Spain, where problems of ozone pollution are frequent. An extensive database compiled over two periods, from May to September 2009 and 2010, is used to evaluate meteorological simulations and chemical outputs. Our results indicate that the model accurately reproduces hourly and 1-h and 8-h maximum ozone surface concentrations measured at the air quality stations, as statistical values fall within the EPA and EU recommendations. However, to further improve forecast accuracy, three simple bias-adjustment techniques mean subtraction (MS), ratio adjustment (RA), and hybrid forecast (HF) based on 10 days of available comparisons are applied. The results show that the MS technique performed better than RA or HF, although all the bias-adjustment techniques significantly reduce the systematic errors in ozone forecasts.

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How a stimulus or a task alters the spontaneous dynamics of the brain remains a fundamental open question in neuroscience. One of the most robust hallmarks of task/stimulus-driven brain dynamics is the decrease of variability with respect to the spontaneous level, an effect seen across multiple experimental conditions and in brain signals observed at different spatiotemporal scales. Recently, it was observed that the trial-to-trial variability and temporal variance of functional magnetic resonance imaging (fMRI) signals decrease in the task-driven activity. Here we examined the dynamics of a large-scale model of the human cortex to provide a mechanistic understanding of these observations. The model allows computing the statistics of synaptic activity in the spontaneous condition and in putative tasks determined by external inputs to a given subset of brain regions. We demonstrated that external inputs decrease the variance, increase the covariances, and decrease the autocovariance of synaptic activity as a consequence of single node and large-scale network dynamics. Altogether, these changes in network statistics imply a reduction of entropy, meaning that the spontaneous synaptic activity outlines a larger multidimensional activity space than does the task-driven activity. We tested this model's prediction on fMRI signals from healthy humans acquired during rest and task conditions and found a significant decrease of entropy in the stimulus-driven activity. Altogether, our study proposes a mechanism for increasing the information capacity of brain networks by enlarging the volume of possible activity configurations at rest and reliably settling into a confined stimulus-driven state to allow better transmission of stimulus-related information.

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BACKGROUND: Lung clearance index (LCI), a marker of ventilation inhomogeneity, is elevated early in children with cystic fibrosis (CF). However, in infants with CF, LCI values are found to be normal, although structural lung abnormalities are often detectable. We hypothesized that this discrepancy is due to inadequate algorithms of the available software package. AIM: Our aim was to challenge the validity of these software algorithms. METHODS: We compared multiple breath washout (MBW) results of current software algorithms (automatic modus) to refined algorithms (manual modus) in 17 asymptomatic infants with CF, and 24 matched healthy term-born infants. The main difference between these two analysis methods lies in the calculation of the molar mass differences that the system uses to define the completion of the measurement. RESULTS: In infants with CF the refined manual modus revealed clearly elevated LCI above 9 in 8 out of 35 measurements (23%), all showing LCI values below 8.3 using the automatic modus (paired t-test comparing the means, P < 0.001). Healthy infants showed normal LCI values using both analysis methods (n = 47, paired t-test, P = 0.79). The most relevant reason for false normal LCI values in infants with CF using the automatic modus was the incorrect recognition of the end-of-test too early during the washout. CONCLUSION: We recommend the use of the manual modus for the analysis of MBW outcomes in infants in order to obtain more accurate results. This will allow appropriate use of infant lung function results for clinical and scientific purposes. Pediatr Pulmonol. 2015; 50:970-977. © 2015 Wiley Periodicals, Inc.

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The international HyMeX (Hydrological Mediterranean Experiment) program aims to improve our understanding of the water cycle in the Mediterranean, using a multidisciplinary and multiscale approach and with emphasis on extreme events. This program will improve our understanding and our predictive ability of hydrometeorological hazards including their evolution within the next century. One of the most important results of the program will be its observational campaigns, which will greatly improve the data available, leading to significant scientific results. The interest of the program for the Spanish research groups is described, as the active participation of some of them in the design and execution of the observational activities. At the same time, due to its location, Spain is key to the program, being a good observation platform. HyMeX will enrich the work of the Spanish research groups, it will improve the predictive ability of the weather services, will help us to have a better understanding of the impacts of hydrometeorological extremes on our society and will lead to better strategies for adapting to climate change.