Process modelling for information system description

My previous experiences and some preliminary studies of the relevant technical literature allowed me to identify several reasons for which the current state of the database theory seemed unsatisfactory and required further research. These reasons included: insufficient formalism of data semantics, misinterpretation of NULL values, inconsistencies in the concept of the universal relation, certain ambiguities in domain definition, and inadequate representation of facts and constraints. The commonly accepted ’sequentiality’ principle in most of the current system design methodologies imposes strong restrictions on the processes that a target system is composed of. They must be algorithmic and must not be interrupted during execution; neither may they have any parallel subprocesses as their own components. This principle can no longer be considered acceptable. In very many existing systems multiple processors perform many concurrent actions that can interact with each other. The overconcentration on data models is another disadvantage of the majority of system design methods. Many techniques pay little (or no) attention to process definition. They assume that the model of the Real World consists only of data elements and relationships among them. However, the way the processes are related to each other (in terms of precedence relation) may have considerable impact on the data model. It has been assumed that the Real World is discretisable, i.e. it may be modelled by a structure of objects. The word object is to be interpreted in a wide sense so it can mean anything within the boundaries of this part of the Real World that is to be represented in the target system. An object may then denote a fact or a physical or abstract entity, or relationships between any of these, or relationships between relationships, or even a still more complex structure. The fundamental hypothesis was formulated stating the necessity of considering the three aspects of modelling - syntax, semantics and behaviour, and these to be considered integrally. A syntactic representation of an object within a target system is called a construct A construct which cannot be decomposed further (either syntactically or semantically) is defined to be an atom. Any construct is a result of the following production rules: construct ::= atom I function construct; function ::= atom I construct. This syntax forms a sentential notation. The sentential notation allows for extensive use of denotational semantics. The meaning of a construct may be defined as a function mapping from a set of syntactic constructs to the appropriate semantic domains; these in turn appear to be sets of functions since a construct may have a meaning in more than one class of objects. Because of its functional form the meaning of a construct may be derived from the meaning of its components. The issue of system behaviour needed further investigation and a revision of the conventional model of computing. The sequentiality principle has been rejected, concurrency being regarded as a natural property of processes. A postulate has been formulated that any potential parallelism should be constructively used for data/process design and that the process structure would affect the data model. An important distinction has been made between a process declaration - considered as a form of data or an abstraction of knowledge - and a process application that corresponds to a physical action performed by a processor, according to a specific process declaration. In principle, a process may be applied to any construct - including its own representation - and it is a matter of semantics to state whether or not it is sensible to do so. The process application mechanism has been explained in terms of formal systems theory by introducing an abstract machine with two input and two output types of channels. The system behaviour has been described by defining a process calculus. It is based on logical and functional properties of a discrete time model and provides a means to handle expressions composed of process-variables connected by logical functors. Basic terms of the calculus are: constructs and operations (equivalence, approximation, precedence, incidence, free-parallelism, strict-parallelism). Certain properties of these operations (e.g. associativity or transitivity) allow for handling large expressions. Rules for decomposing/integrating process applications, analogous in some sense to those forming the basis for structured programming, have been derived

Longitudinal antimüllerian hormone and its correlation with pubertal milestones.

ObjectiveTo examine the changes in AMH levels longitudinally over time and their relationship with both body composition, particularly abdominal adiposity, and milestones of pubertal development in female children.DesignSecondary analysis of a prospective, longitudinal study.SettingUniversity affiliated research center and laboratories.PatientsEighty-nine females were examined between 1990 and 2015 to study child growth and development.InterventionsDemographic, anthropometric, growth, and pubertal milestone data with serum samples stored and subsequently analyzed for AMH.Main outcome measuresLongitudinal change in AMH and predicted AMH levels based on body composition, age, and pubertal milestones including, pubarche, thelarche, and menarche.ResultsNatural log-transformed AMH (AMHlog) levels appeared to have a nonlinear relationship with age, decreasing between 10 and 14 years of age, increasing until 16 years. A mixed effect linear model demonstrated that increased abdominal adiposity (waist/height ratio, WHtR) was significantly associated with the predicted increased AMHlog levels (β=1.37). As females progressed through the Tanner stages, the model predicted decreasing AMHlog values when adjusting for age and WHtR.ConclusionsDeclining AMH levels during puberty may not be reflective of diminished ovarian reserve as observed in adults, but may suggest a permissive role of AMH in the activation of the hypothalamic-pituitary-ovarian axis

Longitudinal antimüllerian hormone and its correlation with pubertal milestones

Objective: To examine the changes in AMH levels longitudinally over time and their relationship with both body composition, particularly abdominal adiposity, and milestones of pubertal development in female children. Design: Secondary analysis of a prospective, longitudinal study. Setting: University affiliated research center and laboratories. Patient(s): Eighty-nine females were examined between 1990 and 2015 to study child growth and development. Intervention(s): Demographic, anthropometric, growth, and pubertal milestone data with serum samples stored and subsequently analyzed for AMH. Main Outcome Measure(s): Longitudinal change in AMH and predicted AMH levels based on body composition, age, and pubertal milestones including, pubarche, thelarche, and menarche. Result(s): Natural log-transformed AMH (AMHlog) levels appeared to have a nonlinear relationship with age, decreasing between 10 and 14 years of age, increasing until 16 years. A mixed effect linear model demonstrated that increased abdominal adiposity (waist/height ratio, WHtR) was significantly associated with the predicted increased AMHlog levels (β=1.37). As females progressed through the Tanner stages, the model predicted decreasing AMHlog values when adjusting for age and WHtR. Conclusion(s): Declining AMH levels during puberty may not be reflective of diminished ovarian reserve as observed in adults, but may suggest a permissive role of AMH in the activation of the hypothalamic-pituitary-ovarian axis

Physically Constrained Receptor Modelling of PM10 from Winter Time Krakow

Krakow is Poland¿s second largest city and one of the most polluted cities in Europe with regards to particulate matter (PM) and associated compounds, such as benzo(a)pyrene (B(a)P). The study was designed to apportion coal combustion sources in comparison with other main sources for these pollutants PM10 samples were collected in Krakow during typical winter pollution events from 5 sampling sites, all with little different source profiles, industry, traffic, residential, urban background and rural background areas. The receptor samples were chemically analyzed together with PM emissions samples from 20 major sources and the obtained data was subjected to multivariate receptor modeling. 46 individual compounds were included comprising elementary and organic carbon (EC/OC), major anions and cations, trace elements, polyaromatic hydrocarbons and azaarenes. The source apportionment was accomplished by physically constrained positive matrix factorization (CMF). The hybrid receptor model between chemical mass balance and factor analysis with physically meaningful constraints was developed in the early 90ties by Wåhlin (Wåhlin, 1993). Subject for constraints was to gain reduced rotational ambiguity and physically more interpretable factors. In this study, these ideas are developed further by not only constraining ratios of specific elements, but allowing the constraint to be variable within uncertainty limits. The limits for constraints can be obtained from experimental uncertainties of source profiles or expert knowledge about specific elemental ratios, e.g. evaporation or chemical transformation that changes the original source fingerprint from one form to an other. Furthermore, the uncertainties for semivolatile PACs were scaled using temperature corrected subcooled liquid vapor pressures (Fernández et al., 2002). CMF takes advantage of the multi-linear engine ME-2 model tool developed by Paatero,(1999), which facilitate the running of PMF in various constrained modes. The highest primary contributions to the PM10 pollution in the city of Krakow and in particularbackground site Zakopane was from Home heating. In Krakow this source covers 30-50% andin Zakopane to 80-90% of total PM10, which is in agreement with high number of small stoves in Krakow and Zakopane. The second highest primary contribution of PM10 was estimated to come from industrial power generation (coal), 30-40% in Krakow and 5-10% in Zakopane to 80-90%. Traffic and re-suspension was estimated by to be lowest primary source explains to 8-10% in Krakow and less than 2% in Zakopane. The contribution from secondary aerosols was estimated to contribute with 20-21% in Krakow and less than 8-10% in Zakopane.JRC.H.4-Transport and air qualit

Are hospitalized or ambulatory patients with heart failure treated in accordance with European Society of Cardiology guidelines? Evidence from 12 440 patients of the ESC Heart Failure Long-Term Registry.

AIMS: To evaluate how recommendations of European guidelines regarding pharmacological and non-pharmacological treatments for heart failure (HF) are adopted in clinical practice. METHODS AND RESULTS: The ESC-HF Long-Term Registry is a prospective, observational study conducted in 211 Cardiology Centres of 21 European and Mediterranean countries, members of the European Society of Cardiology (ESC). From May 2011 to April 2013, a total of 12 440 patients were enrolled, 40.5% with acute HF and 59.5% with chronic HF. Intravenous treatments for acute HF were heterogeneously administered, irrespective of guideline recommendations. In chronic HF, with reduced EF, renin-angiotensin system (RAS) blockers, beta-blockers, and mineralocorticoid antagonists (MRAs) were used in 92.2, 92.7, and 67.0% of patients, respectively. When reasons for non-adherence were considered, the real rate of undertreatment accounted for 3.2, 2.3, and 5.4% of the cases, respectively. About 30% of patients received the target dosage of these drugs, but a documented reason for not achieving the target dosage was reported in almost two-thirds of them. The more relevant reasons for non-implantation of a device, when clinically indicated, were related to doctor uncertainties on the indication, patient refusal, or logistical/cost issues. CONCLUSION: This pan-European registry shows that, while in patients with acute HF, a large heterogeneity of treatments exists, drug treatment of chronic HF can be considered largely adherent to recommendations of current guidelines, when the reasons for non-adherence are taken into account. Observations regarding the real possibility to adhere fully to current guidelines in daily clinical practice should be seriously considered when clinical practice guidelines have to be written

Hyponatraemia and changes in natraemia during hospitalization for acute heart failure and associations with in-hospital and long-term outcomes - from the ESC HFA EORP Heart Failure Long-Term Registry

Aims: To comprehensively assess hyponatraemia in acute heart failure (AHF) regarding prevalence, associations, hospital course, and post-discharge outcomes. Methods and results: Of 8,298 patients in the ESC-HF Long-Term Registry hospitalized for AHF with any ejection fraction, 20% presented with hyponatraemia (serum sodium <135 mmol/L). Independent predictors included lower systolic blood pressure, estimated glomerular filtration rate (eGFR) and haemoglobin, along with diabetes, hepatic disease, use of thiazide diuretics, mineralocorticoid receptor antagonists, digoxin, higher doses of loop diuretics, and non-use of angiotensin-converting-enzyme inhibitors/angiotensin receptor blockers and beta-blockers. In-hospital death occurred in 3.3%. The prevalence of hyponatraemia and in-hospital mortality with different combinations were: 9% hyponatraemia both at admission and discharge (hyponatraemia Yes/Yes, in-hospital mortality 6.9%), 11% Yes/No (in-hospital mortality 4.9%), 8% No/Yes (in-hospital mortality 4.7%), and 72% No/No (in-hospital mortality 2.4%). Correction of hyponatraemia was associated with improvement in eGFR. In-hospital development of hyponatraemia was associated with greater diuretic use and worsening eGFR but also more effective decongestion. Among hospital survivors, 12-month mortality was 19% and adjusted hazard ratios were for hyponatraemia Yes/Yes 1.60 (1.35-1.89), Yes/No 1.35 (1.14-1.59), and No/Yes 1.18 (0.96-1.45). For death or HF hospitalization they were 1.38 (1.21-1.58), 1.17 (1.02-1.33), and 1.09 (0.93-1.27), respectively. Conclusion: Among patients with AHF, 20% had hyponatraemia at admission, which was associated with more advanced HF and normalized in half of patients during hospitalization. Admission hyponatraemia (possibly dilutional), especially if it did not resolve, was associated with worse in-hospital and post-discharge outcomes. Hyponatraemia developing during hospitalization (possibly depletional) was associated with lower risk. This article is protected by copyright. All rights reserved