Spreading of a density front in the K\"untz-Lavall\'ee model of porous media

We analyze spreading of a density front in the K\"untz-Lavall\'ee model of porous media. In contrast to previous studies, where unusual properties of the front were attributed to anomalous diffusion, we find that the front evolution is controlled by normal diffusion and hydrodynamic flow, the latter being responsible for apparent enhancement of the front propagation speed. Our finding suggests that results of several recent experiments on porous media, where anomalous diffusion was reported based on the density front propagation analysis, should be reconsidered to verify the role of a fluid flow

Finite-size anisotropy in statistically uniform porous media

Anisotropy of the permeability tensor in statistically uniform porous media of sizes used in typical computer simulations is studied. Although such systems are assumed to be isotropic by default, we show that de facto their anisotropic permeability can give rise to significant changes of transport parameters such as permeability and tortuosity. The main parameter controlling the anisotropy is $a/L$, being the ratio of the obstacle to system size. Distribution of the angle $\alpha$ between the external force and the volumetric fluid stream is found to be approximately normal, and the standard deviation of $\alpha$ is found to decay with the system size as $(a/L)^{d/2}$, where $d$ is the space dimensionality. These properties can be used to estimate both anisotropy-related statistical errors in large-scale simulations and the size of the representative elementary volume.Comment: 7 pages, 9 figure

Effect of Aging on A1C Levels in Individuals Without Diabetes: Evidence from the Framingham Offspring Study and the National Health and Nutrition Examination Survey 2001–2004

OBJECTIVE—Although glycemic levels are known to rise with normal aging, the nondiabetic A1C range is not age specific. We examined whether A1C was associated with age in nondiabetic subjects and in subjects with normal glucose tolerance (NGT) in two population-based cohorts

Glucokinase (GCK) Mutations and Their Characterization in MODY2 Children of Southern Italy

Type 2 Maturity Onset Diabetes of the Young (MODY2) is a monogenic autosomal disease characterized by a primary defect in insulin secretion and hyperglycemia. It results from GCK gene mutations that impair enzyme activity. Between 2006 and 2010, we investigated GCK mutations in 66 diabetic children from southern Italy with suspected MODY2. Denaturing High Performance Liquid Chromatography (DHPLC) and sequence analysis revealed 19 GCK mutations in 28 children, six of which were novel: p.Glu40Asp, p.Val154Leu, p.Arg447Glyfs, p.Lys458_Cys461del, p.Glu395_Arg397del and c.580-2A>T. We evaluated the effect of these 19 mutations using bioinformatic tools such as Polymorphism Phenotyping (Polyphen), Sorting Intolerant From Tolerant (SIFT) and in silico modelling. We also conducted a functional study to evaluate the pathogenic significance of seven mutations that are among the most severe mutations found in our population, and have never been characterized: p.Glu70Asp, p.His137Asp, p.Phe150Tyr, p.Val154Leu, p.Gly162Asp, p.Arg303Trp and p.Arg392Ser. These seven mutations, by altering one or more kinetic parameters, reduced enzyme catalytic activity by >40%. All mutations except p.Glu70Asp displayed thermal-instability, indeed >50% of enzyme activity was lost at 50°C/30 min. Thus, these seven mutations play a pathogenic role in MODY2 insurgence. In conclusion, this report revealed six novel GCK mutations and sheds some light on the structure-function relationship of human GCK mutations and MODY2

Organisation changes in Polish agriculture in the last 10 years on the background of the EU

Transformation to a market economy in 1990 year and accession to the European Union in 2004 year had a big impact on the functioning of our agricultural sector and the organisation of farms in Poland. The aim of the paper is try to determine the organisation changes and process of production concentration in Polish agriculture on the background of selected countries in EU. The results indicate that the concentration and specialisation of production is necessary for economic and organisational reasons. This underpins the increase in productivity, improvement of the economic condition and easier sale of agricultural products. Unfortunately, these processes are also associated with an increase in pressure from agriculture on the natural environment

Assessment of regional diversity of correlations between environmental and organisational-production factors in Polish agriculture

W pracy oceniono regionalne zróżnicowanie interakcji pomiędzy czynnikami przyrodniczymi i organizacyjnymi w polskim rolnictwie. Przeprowadzona w ujęciu dynamicznym analiza obejmowała lata 2002-2013, a wskaźniki dla poszczególnych województw porównywano do średnich dla Polski, jako układu odniesienia. W badaniach, oprócz statystyk opisowych, zastosowano również grupowanie województw z wykorzystaniem analizy skupień metodą k-średnich. Przeprowadzone badania wskazują, że kierunek i siła wzajemnego oddziaływania wybranych czynników przyrodniczych i organizacyjnych jest zróżnicowana pomiędzy poszczególnymi regionami Polski. Obserwowane ogólnokrajowe tendencje i wzajemne zależności analizowanych czynników przyrodniczych i organizacyjnych nie odzwierciedlają właściwie skali i skutków ich zmian w różnych regionach kraju. Ze względu na wieloczynnikowe uwarunkowania prowadzenia produkcji rolniczej skutki ich oddziaływania w poszczególnych regionach są mocno zróżnicowane. Przejawem tego jest realizacja, w poszczególnych częściach Polski, odmiennych modeli produkcji rolniczej, charakteryzujących się różnym poziomem organizacji i intensywności. Dokonana analiza wskazuje na konieczności regionalizacji krajowej polityki rolnej, w tym Programu Rozwoju Obszarów Wiejskich. Podejście takie powinno przyczynić się do bardziej efektywnego wydatkowania środków kierowanych do rolnictwa i na obszary wiejskie, poprzez optymalizowanie procesu ich rozwoju.In the paper are assessed regional differences in the interaction between the natural and organizational factors in Polish agriculture. The analysis carried out in the dynamic approach covering the years 2002-2013, and the indicators for individual voivodships were compared to the average for Polish as a reference system. In research, in addition to descriptive statistics, it was also used grouping of voivodships with the use of cluster analysis with method of k-means. Conducted research indicates that the direction and strength of the interaction of selected environmental and organizational factors is differentiated between Polish regions. Observed nationwide trends and interdependence of analyzed natural and organizational factors do not reflect properly to the scale and effects of changes in different regions of the country. Because of the multifactorial determinants of agricultural production consequences of their impact in the regions are highly different. Manifestation of this is the realization, in various parts of the Polish, different models of agricultural production, which are characterized by different levels of the organization and intensity. The analysis indicates the need for regionalization of national agricultural policy, including the Rural Development Programme. This approach should contribute to more effective spending of funds addressed to agriculture and rural areas, by optimizing the process of their development

Yielding and biometric characters of energy willow depending on the habitat conditions

Rozwój produkcji roślinnej na cele energetyczne jest zagadnieniem często poruszanym w ostatnich latach. Aktualnie spośród roślin uprawianych na cele energetyczne w krótkiej rotacji największym zainteresowaniem cieszy się wierzba wiciowa. W pracy omówiono plonowanie i cechy biometryczne dziewięciu klonów/odmian tej wierzby, uprawianej w trzech siedliskach. Uzyskiwane plony suchej masy wierzby zbieranej co roku wynosiły, w zależności od warunków siedliska i przebiegu pogody, od 11,1 do 20,4 t x ha-1. Średnio z 5 lat, niezależnie od klonu i odmiany wierzba plonowała od 12,7 t x ha-1 na glebie średniej (kompleks 4) do 14,1 t x ha-1 na glebie lekkiej (kompleks 5). Plon suchej masy wierzby zbieranej w cyklu 3-letnim, średnio dla wszystkich porównywanych klonów i odmian, był na glebie ciężkiej o 28%, a na glebie średniej o 21% większy niż suma plonów z trzech corocznych zbiorów. Zaobserwowano dużą zmienność plonowania w latach, uzależnioną od przebiegu warunków pogodowych, które - oprócz siedliska - determinują poziom uzyskiwanych plonów.The development of crop production for energy purposes is an issue enjoying in last years with the strong interest. Currently, among the crops grown for energy purposes in short rotation, the interest is in the basket willow (Salix viminalis). This paper described the yielding and biometric characteristics of eight willow cultivars grown in three localizations. Dry matter yields of the willow obtained in one year cycle harvest, depending on the habitat and weather conditions, fluctuate between 11.1 and 20.4 t x ha-1. On average for the five years, regardless of cultivar, the willow yielded from 12.7 t x ha-1 on the medium soil to 14.1 t x ha-1 on sandy soil. The yield of willow dry matter per year as harvested in three year cycle - on average for all cultivars compared - was higher by 28% on heavy soil and by 21% on medium soil, than the sum of yields from 3 annual harvests. In the course of experiments high variability of yielding was observed in particular years, as dependent on the weather conditions, which - apart from the habitat - determine the level of yields