Academic literature on the topic 'And Correlations: BasicConcepts and Methods'

In management education and psychology there are certain concepts that cannot bewell defined and then various discussions arise about the true meaning of the concept.Concepts such as management intelligence, personality, attitudes, interests, ambitions, socialprejudice and social status are hypothetical constructs that are not available in operationalmethods that can directly measure them. Concepts such as intelligence, personality, attitudes,interests, ambitions, social prejudice, social status are hypothetical constructs that are notavailable operational methods that can directly measure them. This study aims to determine thebackground of the use of Structural Equation Modeling (SEM), understanding SEM, basicconcepts of SEM: constructs, manifest variables, validity, reliability, factor analysis, polycoriccorrelation, causal relationships, LISREL: Linear Structural Relationship, SEM procedures :definition of variance and covariance, model specifications, model identification, modelestimation, model formation, model compatibility test, model specification, LISREL programoutput. Symbols in SEM and SEM mathematical equations. The method used during this studytook place, namely using a literature study method which functions so that in research,researchers continue to add insight.

Conducting survey research involves making choices concerning the methods of gathering attitude data. Several methods are available, each with its advantages and disadvantages. Three methods were compared in this study. They included ratings, rankings, and paired comparisons. The responses of 392 undergraduate students were included in the analyses. Each participant completed a survey consisting of three attitude objects of five items each, one set formatted using a rating scale, another using rankings, and a third using paired comparisons. Three survey forms were developed so that each attitude object could be presented in each format. The three forms were presented randomly to approximately equal numbers of participants. Analyses consisted of obtaining means or scale values for each item. Correlations among methods were computed for each of the three attitude objects. Correlations for one well-researched attitude object were all above .80. Other correlations ranged from .41 to .89. Consistently the highest correlations were between rankings and paired comparisons, a finding that is not surprising in view of the fact that tasks required of these two scales are very similar.

Numerical and statistical methods are used to analyze and classify computer programs. Both computer source code and object files are examined. The results of the application of the Pearson and Spearman correlation methods to the source code are coupled with the random walk model applied to the binary code. One of the practical consequences of the analysis is the ability to quantify the degree of similarity between different computer programs and, hence, identify cases of plagiarism.

We present a method based on three-particle azimuthal correlation cumulants for the study of the interaction of jets with the medium produced in heavy ion collisions at RHIC and LHC where jets cannot be reconstructed on an event-by-event basis with conventional jet finding algorithms. The method is specifically designed to distinguish a range of jet interaction mechanisms such as Mach cone emission, gluon Cerenkov emission, jet scattering, and jet broadening. We discuss how anisotropic flow background conti-butions of second order (e.g. [Formula: see text]) are suppressed in three-particle azimuthal correlation cumulants, and discussed specific model representations of di-jets, away-side scattering, and Mach cone emission.

It is well known that very few models of interacting systems particularly those in dimension higher than two, can be solved exactly. The mean-field treatment is the first step in approximate calculations for such models. Although mean-field approximation leads to sufficiently accurate results of the thermodynamic properties of these systems away from critical points, most often it fails miserably close to the critical points. In this thesis, we propose to study direct methods (not based on any mean-field type approximations) for proving the exponential decay of the two point-correlation functions and the analyticity of the pressure (free energy per unit volume) for models of Kac type. The methods are based on the Helffer-Sjöstrand formula for the covariance in terms of Witten's Laplacians.

Correlation effects in the one-dimensional Hubbard model are studied by application of the L-resolvent method. The calculations are well beyond one-particle mean field approximation. All correlations involving two neighboring sites are included exactly and higher order correlations are approximated. The effects of varying temperature, band filling, Coulomb repulsion and external magnetic field are investigated. Two-site correlations for non-half-filled band fillings are calculated for the first time. Some exact relations between correlation functions are derived by electron-hole symmetry. Results indicate that short-range spin correlations always favor antiferromagnetic order. Large Coulomb repulsion induces a gap in the excitation spectrum and a metal-insulator transition is predicted as the Coulomb repulsion parameter is changed.
Ph. D.

Abstract Background: According to the World Health Organization, 39 million people is completely blind. Between the genetic disorders causing visual impairment, by affecting 1 person to 3000-4000, Inherited Retinal Dystrophies, Occult Macular Dystrophy and Age-related Macular Degeneration are the most diffuse. Inherited Retinal Disorders (IRD) are retinal degenerations caused by mutations in at least 280 genes and more loci. IRD can be both syndromic or not-syndromic, inherited or sporadic, and all the inheritance patterns are possible. In fact, in addition to the autosomal dominant, autosomal recessive and the X-linked forms, sporadic, digenic and mitochondrial ones are possible. One of the most significant characteristics is their great genetic heterogeneity, due to the high number of genes and possible mutations involved. These genes transduce proteins involved in phototransduction and visual cycle processes, expressed in retinal pigmented epithelium or photoreceptors cells. The diseases are progressive and characterized by difficulties in night vision, loss of peripheral vision and photophobia, until complete blindness. Besides the genetic heterogeneity, these pathologies are characterized by allelic and clinical heterogeneity, which make the clinical diagnosis and the genotype-phenotype correlations complex, whenever the genetic cause is known. If genetic heterogeneity is determined by the presence of different mutations that induce the same clinical manifestation, clinical (or allelic) heterogeneity occurs in the presence of mutations on the same gene that cause different phenotypes. While Occult Macular Dystrophy (OMD) is an inherited macular dystrophy caused by mutation in RP1L1 gene with an autosomal dominant pattern of inheritance, Age-related Macular Degeneration (AMD) is a complex disorder caused by an association of genetic, environmental and advanced age susceptibility. Currently no diagnostic tests or definitive treatment for these disorders are available. Aim of the study: The objective of this project is the development of diagnostic tests valid for the genetic characterization of patients affected by IRD or OMD. For this purpose, 620 patients and affected family members were clinically characterized, and a genetic biobank was created from the collection of their DNA, available for possible genetic testing. Based on the pathology they are affected, diagnostic tests were performed using Sanger sequencing or Next Generation Sequencing (NGS), following which correlations between the genotype and the phenotype were made. Materials and methods: IRD patients were recruited and DNA extracted from blood samples. Retinal tissue and biopsies were collected too, in accordance with the current legal regulations. Genetic screening of 190 patients was realized using NGS targeted technology by MiSeq Illumina and identified mutations were then confirmed using Sanger sequencing. Genotype-phenotype correlations were elaborated, and risk factors determination was performed in 118 patients by means TaqMan PCR for 7 polymorphisms. OMD patients were screened for RP1L1 gene and 60 proband suspected to be affected by X-linked retinitis pigmentosa for RP2 and RPGR genes using Sanger sequencing. After a clinical anamnesis and in-depth visual examination, the patients were subjected to blood sampling from which the DNA was extracted and stored in the biobank. In parallel, a retinal biobank was generated from the collection of donors' retinas, collected according to the regulations in force. Genetic screening was performed on 190 patients affected by different autosomal recessive or dominant forms of IRD, using the targeted NGS technology, with panels of 25 genes. After selecting the variants or mutations identified by the analysis, Sanger sequencing was performed to confirm them. The correct attribution of the results to the analyzed individuals was achieved by comparing the genetic profiles obtained from the biobank DNA and the residual one from the NGS analysis. Genetic screening of patients with X-linked forms of IRD (n = 60) or OMD (n = 5) was obtained by means of Sanger sequencing of RPGR and RP2 (IRD) or RP1L1 (OMD) genes. A genetic susceptibility tool was developed and applied to 118 patients (39 of whom previously screened with NGS), using real time PCR, to evaluate the expression of 7 polymorphisms associated with AMD in subjects affected by IRD. Results: With NGS screening 256 variants/mutations were identified in 126 patients. Among these, 49% is represented by novel alterations. The most mutated genes are USH2A (15%) and ABCA4 (14%), while no alteration was found in the BEST1, CRX, LRAT and RLBP1 genes. 27% of cases were completely resolved, while 39% only partially, due to the identification of only one recessive mutation or of variants of uncertain significance. Missense variants cover 80% of the total, followed by nonsense mutations (9%), frameshift insertions/deletions (8%), in-frame insertions/deletions (2%) and splicing alterations (1%). The correlation of the identified genotype with the diagnosed phenotype was possible in about half of genetically characterized patients. From the comparison it was possible to identify triallelic forms, often with the missense G1961E mutation of ABCA4 as an aggravating allele, and a new gene-disease association for the PRPF31 gene that in three patients causes Usher's syndrome. The analysis of the probands with X-linked forms of Retinitis Pigmentosa allowed the identification of a frameshift insertion in the ORF15 of the RPGR gene, a nonsense mutation in RPGR gene and an already known missense mutation in RP2, in three distinct families. Among the patients with OMD, the missense S1199F mutation in RP1L1 was identified for two of them. The susceptibility test for the 7 SNPs showed a high genetic high of AMD in 38 subjects, medium high in 16, medium in 36, and low in 28. Conclusions: NGS technology has proved to be a useful diagnostic tool for the autosomal dominant or autosomal recessive forms of retinal dystrophies, allowing massive and parallel sequencing of many genes and patients. The percentage of genetically characterized patients is consistent with the data in the literature. The use of a panel of genes turns out to be an acceptable compromise between the results obtained and the criticality related to the large amount of output data, compared to whole genome or whole exome sequencing. Much of the genetic data has been correlated with the clinical manifestations of the patients. Sanger technology, gold standard of sequencing, is optimal for the identification of the genetic cause in all pathologies where one or a few genes are involved, such as the X-linked forms of IRD or the OMD. The expression of risk factors, predisposing to macular degeneration, while not correlating with the severity of the confirmed mutations, could provide important relationships with the pathologies of which the subjects are affected. The identification of the genetic causes of these pathologies will bring a new thrust to the development of gene and cell therapies, fundamental for the treatment of hereditary retinal diseases.
Riassunto Presupposti dello studio: Secondo l’organizzazione mondiale della sanità, 39 milioni di persone sono ciechi. Tra principali cause genetiche che inducono compromissione visiva, con una prevalenza di 1:2500-4000, le Distrofie Retiniche Ereditarie (i.e. Inherited Retinal Dystrophy - IRD), la Distrofia Maculare Occulta (OMD) e la Degenerazione Maculare legate all’Età (AMD) sono le più diffuse. Le prime sono un gruppo di patologie che inducono degenerazioni retiniche indotte da mutazione in almeno 280 geni e molti loci. Le forme di IRD possono essere sindromiche o non sindromiche, sporadiche o ereditarie, con tutti i pattern di eredità possibili. Infatti, oltre alle forme autosomiche dominati e recessive e le forme legate al cromosoma X, sono possibili forme sporadiche, digeniche e mitocondriali. Una delle principali caratteristiche di queste patologie è la loro elevata eterogeneità, legata all’elevato numero di geni e di mutazioni coinvolti. Questi geni, infatti, codificano proteine coinvolte nei processi di foto-trasduzione e del ciclo visivo, espressi principalmente nelle cellule dell’epitelio pigmentato retinico o nei fotorecettori. Queste malattie hanno un andamento progressivo che inizia, generalmente, con difficoltà nella visione notturna, perdita della visione periferica e fotofobia, fino alla cecità assoluta. Oltre alla eterogeneità genetica, queste patologie sono caratterizzate da eterogeneità allelica e clinica, che rendono complessa la diagnosi clinica ed anche le correlazioni genotipo-fenotipo, qualora si conosca la causa genetica del paziente. Se l‘eterogeneità genetica è determinata dalla presenza di differenti mutazioni che inducono la stessa manifestazione clinica, l’eterogeneità clinica (o allelica) si ha in presenza di mutazioni sullo stesso gene che causano fenotipi differenti. Mentre la Degenerazione Maculare Occulta è una distrofia maculare ereditaria causata da mutazioni nel gene RP1L1, con una trasmissione autosomica dominate, la Degenerazione Maculare legata all’Età è una patologia complessa causata dall’associazione di fattori genetici, ambientali e dall’età avanzata. Attualmente per queste patologie non sono disponibili né test diagnostici né cure. Scopo dello studio: L’obiettivo di questo progetto è lo sviluppo di test diagnostici validi per la caratterizzazione genetica dei pazienti affetti da IRD o OMD. Per tale scopo, 620 pazienti e familiari affetti sono stati clinicamente caratterizzati e dalla collezione dei loro DNA è stata creata una biobanca genetica disponibile per eventuali test genetici. In base alla patologia di cui sono affetti, i test diagnostici sono stati eseguiti mediante utilizzo di Sanger sequencing o Next Generation Sequencing (NGS) al seguito del quale sono stati realizzate delle correlazioni tra il genotipo e il fenotipo. Materiali e metodi: Dopo anamnesi clinica e approfondito esame visivo, i pazienti sono stati sottoposti a prelievo di sangue da cui è stato estratto il DNA stoccato all’interno della biobanca. In parallelo una biobanca retinica è stata generata dalla collezione di retine di domatori, raccolte in accordo alle normative vigenti. Lo screening genetico è stato eseguito su 190 pazienti affetti da differenti forme autosomiche recessive o dominanti di IRD, mediante la tecnologia targeted NGS, con pannelli di 25 geni. Dopo la selezione delle varianti o mutazioni identificate dall’analisi, è stato eseguito il sequenziamento Sanger per la loro conferma. La corretta attribuzione dei risultati agli individui analizzati è stata realizzata grazie alla comparazione di profili genetici ottenuti dal DNA della biobanca e quello residuo dall’analisi NGS. Lo screening genetico, dei pazienti affetti da forme X-linked di IRD (n=60) o da OMD (n=5) è stato ottenuto da sequenziamento Sanger dei geni RPGR e RP2 (IRD) o RP1L1 (OMD). Un test di suscettibilità genetica è stato sviluppato e applicato a 118 pazienti (39 dei quali precedentemente screenati con NGS), mediante real time PCR, per valutare l’espressione di 7 polimorfismi associati all’AMD nei soggetti affetti da IRD. Risultati: Con lo screening NGS 256 varianti/mutazioni sono state identificate in 126 pazienti. Tra queste il 49% è rappresentato da alterazioni non note in letteratura. I geni maggiormente mutati sono USH2A (15%) e ABCA4 (14%), mentre nessuna alterazione è stata riscontrata nei geni BEST1, CRX, LRAT and RLBP1. Il 27% dei casi è stato completamente risolto, mentre il 39% solo parzialmente, a causa dell’identificazioni di una sola mutazione recessiva o di varianti di significato incerto. Le varianti missenso coprono l'80% del totale, seguite dalle mutazioni nonsenso (9%), dalle inserzioni/delezioni frameshift (8%), dalle inserzioni/delezioni in-frame (2%) e dalle alterazioni di splicing (1%). La correlazione del genotipo identificato con il fenotipo diagnosticato è stata possibile in quasi la metà dei pazienti geneticamente caratterizzati. Dalla comparazione è stato possibile identificare forme trialleliche, con la mutazione missenso G1961E di ABCA4 come allele aggravante, e una nuova associazione gene-malattia per il gene PRPF31 che in tre pazienti causa la sindrome di Usher. L’analisi dei probandi affetti da forme X-linked di Retinite Pigmentosa ha permesso l’identificazione di un’inserzione framshift nell’ORF15 del gene RPGR, una mutazione nonsenso in RPGR gene e una mutazione missenso nota in RP2, in tre famiglie distinte. Tra i pazienti affetti da OMD, è stata identificato per due di essi la mutazione missenso S1199F in RP1L1. Il test di suscettibilità per i 7 SNP ha evidenziato un elevato alto genetico di AMD in 38 soggetti, medio alto in 16, medio in 36, e basso in 28. Conclusioni: La tecnologia NGS si è rivelata un utile strumento diagnostico per le forme autosomiche dominanti o recessive di distrofie retiniche, permettendo il sequenziamento massivo e parallelo di molti geni e pazienti. La percentuale di pazienti geneticamente caratterizzati è coerente con i dati presenti in letteratura. L’uso di un pannello di geni risulta essere un accettabile compromesso tra la i risultati ottenuti e le criticità legate alla grande quantità di dati output, rispetto alle analisi di whole genome o whole exome sequencing. Buona parte dei dati genetici sono stati correlati alle manifestazioni cliniche dei pazienti. La tecnologia Sanger, gold standard del sequenziamento, è ottimale per l’identificazione della causa genetica in tutte le patologie ove uno o pochi geni sono coinvolti, come le forme X-linked di IRD o la OMD. L’espressione di fattori di rischio, predisponenti alla degenerazione maculare, pur non correlando con la severità delle mutazioni confermate, potrebbe fornire importanti relazioni con le patologie di cui i soggetti sono affetti. L'identificazione delle cause genetiche di queste patologie porterà una nuova spinta nello sviluppo di nuove terapie geniche e cellulari, fondamentali per il trattamento delle patologie retiniche ereditarie.

Combining multiple forecasts in order to generate a single, more accurate one is a well-known approach. A simple average of forecasts has been found to be robust despite theoretically better approaches, increasing availability in the number of expert forecasts, and improved computational capabilities. The dominance of a simple average is related to the small sample sizes and to the estimation errors associated with more complex methods. We study the role that expert correlation, multiple experts, and their relative forecasting accuracy have on the weight estimation error distribution. The distributions we find are used to identify the conditions when a decision maker can confidently estimate weights versus using a simple average. We also propose an improved expert weighting approach that is less sensitive to covariance estimation error while providing much of the benefit from a covariance optimal weight. These two improvements create a new heuristic for better forecast aggregation that is simple to use. This heuristic appears new to the literature and is shown to perform better than a simple average in a simulation study and by application to economic forecast data.

The purpose of the current study was to address the relationship between Body Mass Index (BMI) status and psychological distress within the adolescent population. Data was acquired from the California Health Interview Survey (CHIS) 2011-2012, a state-wide phone survey which addresses health issues among the resident population. The present study used data from 2,1 04 California adolescents, utilizing variables relating to demographics, general health condition, and mental health.

Results indicated a statistically significant relationship between BMI and psychological distress, with overweight adolescents experiencing more distress and depression than their underweight/healthy weight counterparts. Gender and perceived general health condition were both significantly related to distress, with females and those of poor perceived general health condition experiencing greater psychological distress, regardless of weight status. This study has implications for social work policy and practice, especially in work with youth and families.

Abstract Increasing environmental and economic awareness are driving the development of combustion technologies to efficient biomass use and clean burning. To accomplish these goals, quantitative information about combustion variables is needed. However, for small-scale combustion units the existing monitoring methods are often expensive or complex. This study aimed to quantify correlations between flue gas temperatures and combustion variables, namely typical emission components, heat output, and efficiency. For this, data acquired from four small-scale combustion units and a large circulating fluidised bed boiler was studied. The fuel range varied from wood logs, wood chips, and wood pellets to biomass residue. Original signals and a defined set of their mathematical transformations were applied to data analysis. In order to evaluate the strength of the correlations, a multivariate distance measure based on information theory was derived. The analysis further assessed time-varying signal correlations and relative time delays. Ranking of the analysis results was based on the distance measure. The uniformity of the correlations in the different data sets was studied by comparing the 10-quantiles of the measured signal. The method was validated with two benchmark data sets. The flue gas temperatures and the combustion variables measured carried similar information. The strongest correlations were mainly linear with the transformed signal combinations and explicable by the combustion theory. Remarkably, the results showed uniformity of the correlations across the data sets with several signal transformations. This was also indicated by simulations using a linear model with constant structure to monitor carbon dioxide in flue gas. Acceptable performance was observed according to three validation criteria used to quantify modelling error in each data set. In general, the findings demonstrate that the presented signal transformations enable real-time approximation of the studied combustion variables. The potentiality of flue gas temperatures to monitor the quality and efficiency of combustion allows development toward cost effective control systems. Moreover, the uniformity of the presented signal correlations could enable straightforward copies of such systems. This would cumulatively impact the reduction of emissions and fuel consumption in small-scale biomass combustion
Tiivistelmä Kasvava ympäristö- ja kustannustietoisuus ohjaa polttoteknologioiden kehitystä yhä tehokkaampaan biomassan hyödyntämiseen ja puhtaampaan palamiseen. Näiden tavoitteiden saavuttamiseen tarvitaan mittaustietoa palamismuuttujista. Nykyiset palamisen seurantaan tarkoitetut ratkaisut ovat kuitenkin pienpolttolaitteita ajatellen usein kalliita tai monimutkaisia. Tässä työssä tutkittiin mitattujen savukaasun lämpötilojen riippuvuussuhdetta tyypillisiin kaasukomponentteihin, lämpötehoon ja tehokkuuteen. Tätä varten analysoitiin mittausaineistot neljästä erityyppisestä pienpolttolaitteesta ja suuresta kiertoleijupeti-kattilasta. Puupolttoaineina olivat klapi, hake, pelletti ja hakkuujäte. Analyysi tehtiin alkuperäisillä mittaussignaaleilla ja niistä matemaattisesti muunnetuilla signaaleilla. Riippuvuussuhteiden selvittämiseksi johdettiin informaatioteoriaan perustuva monimuuttuja-etäisyysmitta, jonka lukuarvolla mitataan signaalien samankaltaisuutta. Esitetty analyysimenetelmä sisälsi myös riippuvuuksien ajallisen muutoksen ja suhteellisten aikaviiveiden arvioinnin. Tulosten arvojärjestys perustui etäisyysmitan arvoon. Riippuvuussuhteiden samankaltaisuutta mittausaineistojen välillä vertailtiin 10-kvantiileilla. Analyysimenetelmän toimivuus vahvistettiin kahdella tunnetulla koeaineistolla. Savukaasun lämpötilojen ja palamismuuttujien mittaussignaaleissa oli samankaltainen informaatiosisältö. Vahvimmat riippuvuudet olivat muunnettujen signaalien yhdistelmillä pääosin lineaarisia ja palamisteorian mukaisia. Merkittävää oli, että tietyillä signaalimuunnos- ja palamismuuttujapareilla oli sama riippuvuussuhde kaikissa mittausaineistossa. Tämä todettiin myös simuloinneilla arvioitaessa savukaasujen hiilidioksidipitoisuutta lineaarisella, kiinteällä mallirakenteella. Mallin tarkkuus oli riittävä kolmella erityyppisellä kriteerillä jokaisessa mittausaineistossa. Tulosten perusteella signaalimuunnoksilla voidaan arvioida palamismuuttujia reaaliaikaisesti. Savukaasujen lämpötilojen potentiaali palamisen laadun ja tehokkuuden seurannassa mahdollistaa kustannustehokkaiden säätöratkaisujen kehityksen. Löydettyjä yleistettäviä riippuvuussuhteita hyödyntämällä niiden käyttöönotto lukuisissa polttolaitteissa helpottuisi. Pienpolton päästöjen ja polttoaineen kulutuksen vähentyminen olisi tällöin kumulatiivista

Due to civilian noise complaints and damage claims, there is a need to establish an accurate record of impulse noise generated at military installations. Current noise monitoring systems are susceptible to false positive detection of impulse events due to wind noise. In order to analyze the characteristics of noise events, multiple channel data methods were investigated. A microphone array was used to collect four channel data of military impulse noise and wind noise. These data were then analyzed using cross-correlation functions to characterize the input waveforms. Four different analyses of microphone array data are presented. A new value, the min peak correlation coefficient, is defined as a measure of the likelihood that a given waveform originated from a correlated noise source. Using a sound source localization technique, the angle of incidence of the noise source can be calculated. A method was also developed to combine the four individual microphone channels into one. This method aimed to preserve the correlated part of the overall signal, while minimizing the effects of uncorrelated noise, such as wind. Lastly, a statistical method called the acoustic likelihood test is presented as a method of determining if a signal is correlated or not.

Recently the statistical characterizations of financial markets based on physics concepts and methods attract considerable attentions. The correlation matrix formalism and concept of multifractality are used to study temporal aspects of the Ukraine Stock Market evolution. Random matrix theory (RMT) is carried out using daily returns of 431 stocks extracted from database time series of prices the First Stock Trade System index (www.kinto.com) for the ten-year period 1997-2006. We find that a majority of the eigenvalues of C fall within the RMT bounds for the eigenvalues of random correlation matrices. We test the eigenvalues of C within the RMT bound for universal properties of random matrices and find good agreement with the results for the Gaussian orthogonal ensemble of random matrices—implying a large degree of randomness in the measured cross-correlation coefficients. Further, we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the RMT bound display systematic deviations from the RMT prediction. We analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks. Our analysis of the remaining deviating eigenvectors shows distinct groups, whose identities correspond to conventionally identified business sectors. Comparison with the Mantegna minimum spanning trees method gives a satisfactory consent. The found out the pseudoeffects related to the artificial unchanging areas of price series come into question We used two possible procedures of analyzing multifractal properties of a time series. The first one uses the continuous wavelet transform and extracts scaling exponents from the wavelet transform amplitudes over all scales. The second method is the multifractal version of the detrended fluctuation analysis method (MF-DFA). The multifractality of a time series we analysed by means of the difference of values singularity stregth (or Holder exponent) ®max and ®min as a suitable way to characterise multifractality. Singularity spectrum calculated from daily returns using a sliding 250 day time window in discrete steps of 1. . . 10 days. We discovered that changes in the multifractal spectrum display distinctive pattern around significant “drawdowns”. Finally, we discuss applications to the construction of crushes precursors at the financial markets.

Background : Nonalcoholic fatty liver disease (NAFLD) is increasingly recognized as a cause of chronic liver disease, and often results in the devastating outcomes of decompensated liver cirrhosis and hepatocellular carcinoma and is an important feature of metabolic syndromes and insulin resistance. The assessment of liver brosis is essential for predicting the prognosis and outcome of all forms of chronic liver disease. A liver biopsy is the gold standard for the assessment of liver brosis, but it has its limitations, which include life-threatening complications. Alternative methods of non-invasive laboratory and radiological testing for the assessment of liver brosis in NAFLD have evolved during the past decade, and these methods may be able to overcome the limitations of liver biopsy. These methods include the AST/ALT ratio, the AST platelet ratio index (APRI), and the Fibrosis 4 (FIB-4) score. This study was conducted in order to assess liver brosis using Fibroscan, and to compare these results to the use of AST platelet ratio index (APRI scores), and the AST/ALT ratios on NAFLD patients. METHODS: This was a cross sectional study conducted in King George Hospital Visakhapatnam,A total 122 patients were studied of which 65 were males and 57 were females.all the patients were subjected to relevant investigations including ultrasound abdomen,serum liver enzymes,broscan. The (SPSS) version 20 was used for the analysis.A Student's t-test was used to compare the AST/ALT ratio to the APRI scores between patients with advanced brosis higher than F2 and patients with mild to moderate brosis of F2 or less. RESULTS :The data showed that a high percentage of the NAFLD patients exhibited advanced stages of liver brosis based on the Fibroscan examinations. These results were supported by the strong correlation between the Fibroscan results and the AST/ALT ratio and APRI scores. Correlation analysis showed a signicant positive correlation between age and brosis scores (r = 0.27 with P = 0.004 for Pearson correlations). On the other hand, a signicant negative correlation between platelet count and stiffness scores was obtained (r = - 0.315 with P= 0.001 for Pearson correlations). Serum ALT level was determined to be signicantly negatively correlated with age by using Spearman correlations (r = - 0.232, and P = 0.022). A signicant positive correlation was observed between serum ALT and hepatic stiffness measurements using Spearman correlations (r = 0.284, and P = 0.005). This study has shown that the combination of Fibroscan CONCLUSION: and AST/ALT and APRI methods provides a valuable approach for assessing liver brosis in NAFLD patients. This can eliminate the need for liver biopsy in patients without clear indication

Tis report�reviews research by the Pipeline Research Committee (PRC) of the Pipeline Research Council International Inc. (PRCI, Inc.) related to multiphase flow in pipelines. For the past decade the PRC has sponsored field tests to obtain multiphase data from operating pipelines, laboratory experiments at large pipe size and high gas density, the development of a Design Manual for multiphase methods, and assessment of the methods against data from the fieId and the laboratory, Validation and assessment of mechanistic multiphase predictions against operating data shows a significant improvement of pressure drop and holdup calculations over empirical methods used by many designers and in several popular computer programs. Pressure drop and holdup can be predicted within about 25% with mechanistic methods, whereas correlations are often unreliable except for pipe sizes and flow conditions for the data from which they are derived.

This seminar introduces the Lavaan multilevel latent variable modeling framework and describes multilevel variance and effect decomposition, and then proceeds with multilevel path analysis, multilevel CFA, and multilevel SEM, including approaches for handling strong correlations at the between-group level, indirect effects (multilevel mediation), interaction effects (multilevel moderation), conditional indirect effects (multilevel moderated mediation), bootstrapping, and instrumental variable methods for identifying multilevel causal effects. An official Instats certificate of completion is provided at the conclusion of the seminar. For European PhD students, the seminar offers 2 ECTS Equivalent point.

In this report, we study the use of Multi-Level Monte Carlo (MLMC) methods for time dependent problems. It was found that the usability of MLMC methods depends strongly on whether or not the underlying time dependent problem is chaotic in nature. Numerical experiments are conducted on both simple problems, as well as fluid flow problems of practical interest to the ExaQUte project, to demonstrate this. For the non-chaotic cases, the hypotheses that enable the use of MLMC methods were found to be satisfied. For the chaotic cases, especially the case of high Reynolds’ number fluid flow, the hypotheses were not satisfied. However, it was found that correlations between the different levels were high enough to merit the use of multi-fidelity or control-variate approaches. It was also noted that MLMC methods could work for chaotic problems if the time window of analysis were chosen to be small enough. Future studies are proposed to examine this possibility.

This project is a JIP project with the overall objective of demonstrating that hardness data from randomly selected pipe samples could be used to determine the lower bound YS of an entire pipeline segment at a quantified confidence level, and that results would be conservative in comparison to results determined using the methods currently described in 49 CFR Part 192 and 195. Three different types of field portable hardness testers and a laboratory Rockwell B tester were used on 50 pipe sample. The hardness testing using field portable testers was performed in accordance with ASME CRTD-Vol. 91. The hardness test results were converted to a calculated lower bound YS values using the correlations described in ASME CRTD-Vol. 57. The calculated lower bound YS was compared to the results of standard API 5L tensile tests. In addition, the metallurgical attributes of each pipe were characterized to determine if certain subsets of pipes produced better (or worse) correlations of lower bound YS calculated from hardness data to YS determined from tensile tests. The results showed that hardness data can be used to determine conservative values of lower bound YS using a range of different confidence levels.

A major goal in Israeli and U.S. agroecosystems is to maximize nitrogen availability to crops while minimizing nitrogen losses to air and water resources. This goal has presented a significant challenge to global agronomists and scientists because crops require large inputs of nitrogen (N) fertilizer to maximize yield, but N fertilizers are easily lost to surrounding ecosystems where they contribute to water pollution and greenhouse gas concentrations. Determination of the optimum N fertilizer input is complex because the amount of N produced from soil organic matter varies with time, space and management. Indicators of soil N availability may help to guide requirements for N fertilizer inputs and are increasingly viewed as indicators of soil health To address these challenges and improve N availability indicators, project 4550 “Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile organic matter fractions” addressed the following objectives: Link the quantity and quality of labile soil organic matter fractions to indicators of soil fertility and environmental quality including: i) laboratory potential net N mineralization ii) in situ gross N mineralization iii) in situ N accumulation on ion exchange resins iv) crop uptake of N from mineralized soil organic matter sources (non-fertilizer N), and v) soil nitrate pool size. Evaluate and compare the potential for hot water extractable organic matter (HWEOM) and particulate organic matter quantity and quality to characterize soil N dynamics in biophysically variable Israeli and U.S. agroecosystems that are managed with different N fertility sources. Ultimately, we sought to determine if nitrogen availability indicators are the same for i) gross vs. potential net N mineralization processes, ii) diverse agroecosystems (Israel vs. US) and, iii) management strategies (organic vs. inorganic N fertility sources). Nitrogen availability indicators significantly differed for gross vs. potential N mineralization processes. These results highlight that different mechanisms control each process. Although most research on N availability indicators focuses on potential net N mineralization, new research highlights that gross N mineralization may better reflect plant N availability. Results from this project identify the use of ion exchange resin (IERs) beads as a potential technical advance to improve N mineralization assays and predictors of N availability. The IERs mimic the rhizosphere by protecting mineralized N from loss and immobilization. As a result, the IERs may save time and money by providing a measurement of N mineralization that is more similar to the costly and time consuming measurement of gross N mineralization. In further search of more accurate and cost-effective predictors of N dynamics, Excitation- Emission Matrix (EEM) spectroscopy analysis of HWEOM solution has the potential to provide reliable indicators for changes in HWEOM over time. These results demonstrated that conventional methods of labile soil organic matter quantity (HWEOM) coupled with new analyses (EEM) may be used to obtain more detailed information about N dynamics. Across Israeli and US soils with organic and inorganic based N fertility sources, multiple linear regression models were developed to predict gross and potential N mineralization. The use of N availability indicators is increasing as they are incorporated into soil health assessments and agroecosystem models that guide N inputs. Results from this project suggest that some soil variables can universally predict these important ecosystem process across diverse soils, climate and agronomic management. BARD Report - Project4550 Page 2 of 249

Knowledge of flow regime, holdup and pressure drop is needed in order to design gas and oil pipelines confidently and to minimize construction and operating costs. Previous public studies of two-phase flow in inclined pipes have used small diameter pipes two inches in diameter or less, and have primarily used air and water as the working fluids at low pressure (near one atmosphere). Present design methods are based upon the results of these experiments. In most advanced analyses available today, the flow regime transition is governed by a Froude number, the balance between inertial and buoyancy forces. The primary objective of the work has been to obtain experimental data to challenge the present two-phase flow analysis methods for large pipe size, high gas density, and pipe inclination. Present analysis and design methods for two-phase flow in pipelines are based on correlations of data from small pipes of order 2-inches diameter or less, for air-water flows at pressures near one atmosphere. To achieve this objective, Creare performed experiments in an existing test facility with a special test section assembled for this project. Pipe diameter and gas density are closer to prototypical oil and gas pipeline conditions than previous experiments reported in the literature. The key experimental results include flow regime observations, pressure drops, and holdup measurements. The instrumentation in the test facility allows detailed characteristics of the flow such as slug velocity, slug frequency, liquid film velocity, and slug length to be measured in the slug flow regime.