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Along with a strict determinism of early embryogenesis in most living organisms, some of them exhibit variability of cell fates and developmental pathways. Here we discuss the phenomena of determinism and variability of developmental pathways, defining its dependence upon cell potency, cell sensitivity to the external signals and cell signaling. We propose a set of conjectures on the phenomenon of variability of developmental pathways, and denote a difference between a normal (local) variability, leading to an invariant final structure (e.g., embryo shape), and fundamental one, which is a switching between different developmental pathways, leading to different possible structures. For illustrating our conjectures, we analyzed early developmental stages of plant embryos with different levels of variability of morphogenesis pathways, and provide a set of computational experiments by Morphogenesis Software.

The paper deals with the issues of text mining based on a vector classification model. The term frequency and inverse document frequency function (TF IDF) is used as a measure to evaluate the selection of terms. The text preprocessing stage performs tokenization and normalization of the text. The algorithms of stemming and lemmatization of the Russian-language text are used during normalization. A set of programs has been created that makes it possible to analyze the selected subject area, create a thesaurus for thematic search for violations of the public procurement Federal Law of the Russian Federation, as well as to implement functionality for automated search and analysis of documents of arbitration courts within the framework of this law.

The article consists information about feasibility of foamed polyethylene based materials for a seamless thermal insulation sheath. Foamed polyethylene with and without metallized coating were used for examination. The formation of a seamless sheath is carried out by connecting individual sheets into a lock with subsequent welding of the lock joints with hot air. The strength of the weld is the defining durability characteristic of an insulating seamless sheath. The tensile strength in the longitudinal direction for products with a metallized coating is 80–92 kPa, without a metallized coating – 80–87 kPa, and for a weld joint – 29–32 kPa. The performance characteristics of insulation sheath based on foamed polyethylene meet the requirements for materials and systems operating at negative and alternating temperatures while having low vapor permeability. The features of the implementation of insulation systems in the construction of frame and frameless buildings in agriculture are also described.

The 3D structure of a fire front propagating through a homogeneous porous solid-fuel layer was studied numerically at laboratory and field scales. At laboratory scale, wind-tunnel fires propagating through laser-cut cardboard fuel were numerically reproduced, while at field scale, simulations of grassland fires with quasi-infinite fire front were carried out for different wind speeds. These simulations were performed using FIRESTAR3D, based on a multiphase formulation that includes the main physical phenomena governing fire behavior. An unsteady RANS approach and a Large Eddy Simulation (LES) approach were used to simulate the reactive turbulent flow, whereas turbulent combustion was modeled using Eddy Dissipation Concept (EDC). Unlike other 3D wildfire tools available in the community, such as FIRETEC and WFDS, the model is based on an implicit, low-Mach number resolution of the governing equations, and makes no empirical assumptions in the resolution of the radiative transfer equation. The comparison with the experimental data concerned mainly the Rate of Spread (ROS) of fire, the fireline intensity, the flame-zone depth, and the wavelength characterizing the crest-and-trough structure of the fire front along the transverse direction. Particular attention was drawn to the similitude in the fire front dynamics between small and large scales. In order to highlight the physical mechanisms responsible for this dynamics, a dimensional analysis was carried out by introducing Byram's convection number NC based on the fireline intensity and Froude's numbers Fr based on the characteristic wavelength of the fire-front structure. The analysis shows that all the results (wind-tunnel fires and grassland fires, experimental and numerical) collapsed on a single scaling law in the form F r = N C − 2 / 3 .

In most taxa of plant and animal kingdoms the initial steps of embryogenesis and the final morphology of an organism are strongly determined. However, these two phenomena do not correlate from phylogenetic point of view, namely, different unrelated taxa can have the same type of early embryogenesis, while there can be different types of cleavage inside one taxon. Here we discuss an approach enabling giving an insight into the understanding of this phenomenon. First, we propose a strategy for constructing developmental graphs (trees) that provide mathematical formalization of a process of embryogenesis. Second, we suggested an algorithm of trees comparison, developed specifically for this type of labeled graphs, which allows calculating a distance between two developmental trees, and thus clustering them into groups. Next we performed the analysis of correspondence between the obtained clusters and the inception of morphological characters in given clustered groups of organisms, which allows describing several particular cases of interrelation between developmental trends and formation of morphological structures. Here we present some illustrations of the suggested methodology on the analysis of plant angiosperm species belonging to different taxa of various ranks.

We study a two dimensional version of Neuhauser's long range sexual reproduction model and prove results that give bounds on the critical values λ f for the process to survive from a finite set and λ e for the existence of a nontrivial stationary distribution. Our first result comes from a standard block construction, while the second involves a comparison with the “generic population model” of Bramson and Gray (1991) [3] . An interesting new feature of our work is the suggestion that, as in the one dimensional contact process, edge speeds characterize critical values. We are able to prove the following for our quadratic contact process when the range is large but suspect they are true for two dimensional finite range attractive particle systems that are symmetric with respect to reflection in each axis. There is a speed c ( θ ) for the expansion of the process in each direction. If c ( θ ) > 0 in all directions, then λ > λ f , while if at least one speed is positive, then λ > λ e . It is a challenging open problem to show that if some speed is negative, then the system dies out from any finite set.

A new model describing the periodic vibrations caused by the interaction between the moving ice floe and a simple oscillator is proposed. The equations obtained estimate the forces affecting the oscillator under its interaction with ice. The influence of the velocity of ice movement on different vibration regimes is analysed.

Flows of different fluids through single-walled carbon nanotubes (SWCNTs) with boundary walls having the perfect and defective graphene structures have been investigated by means of molecular dynamics (MD) simulations. It has been shown that the boundary wall structure has a very strong influence on not only an average fluid flow rate but also on shapes of trajectories of individual fluid atoms (molecules) and fluid centres of mass. The fluid flows through SWCNTs surrounded by different liquid environments have been also simulated and an influence of these environments on the average fluid flow rates have been studied. It has been revealed a strong dependence of the average fluid flow rate on a molecular polarity of fluids flowing through SWCNTs and those surrounding the tubes. It has been shown that, for multi-walled carbon nanotubes (MWCNTs), an effect of liquid environment on the fluid flow can be significantly suppressed.

Let $\theta$ be an inner function satisfying the connected level set condition of B. Cohn, and let $K^{1}_{\theta}$ be the shift-coinvariant subspace of the Hardy space $H^1$ generated by $\theta$. We describe the dual space to $K^{1}_{\theta}$ in terms of a bounded mean oscillation with respect to the Clark measure $\sigma_\alpha$ of $\theta$. Namely, we prove that $(K^{1}_{\theta} \cap zH^1)^* = {\rm BMO}(\sigma_\alpha)$. The result implies a two-sided estimate for the operator norm of a finite Hankel matrix of size $n\times n$ via ${\rm BMO}(\mu_{2n})$-norm of its standard symbol, where $\mu_{2n}$ is the Haar measure on the group $\{\xi \in \mathbb{C}: \xi^{2n} = 1\}$., Comment: 24 pages

Background: The self-rated auto-questionnaire, the Temperament Scale of Memphis, Pisa, Paris and San Diego (TEMPS-A) is the latest development in the study of temperamental attributes. It has been used and validated in different cultures and countries. The current study aims at validating the Chinese (Cantonese) version of the TEMPS-A and comparing the psychometric properties of the long and short forms of the translated scale. Methods: The Chinese (Cantonese) version of TEMPS-A was prepared with the standard translation and back-translation method, and approved by the original authors (HSA & KKA). It was administered to medical students of the two local universities, and results were analyzed. Results: 613 valid questionnaires were returned. The Cronbach-Alpha coefficients for the depressive, cyclothymic, hyperthymic, irritable and anxious temperament subscales were 0.63, 0.82, 0.78, 0.80, and 0.84, respectively. The strongest correlation was observed between the cyclothymic and irritable temperaments (R ¼0.600). Factor analysis yielded one large composite (depressive and anxious) and four homogenous factors, cyclothymic, anxious, hyperthymic and irritable. A newly reconstituted 43item short form, based on methods suggested by the original authors yielded similar factor structure. Limitations: The narrow age range of subjects somewhat limits generalization of the results. However, external and concurrent validations against other validated scales have been demonstrated for the original English versions as well as against the most commonly used languages of the world; furthermore, such validation has also been demonstrated for Chinese (Mandarin). Conclusions: The Chinese (Cantonese) version of TEMPS-A and the reconstituted 43-item short form were found to have good internal consistency and factor structures comparable to those of other languages from diverse cultures across the planet. We propose that the Cantonese TEMPS-A is a useful tool for local use.

Background: The purpose is to measure the worsening of the Quality of Life (QoL) in people with Multiple Sclerosis (MS) and the concomitant role of co-morbid Major Depressive Disorder (MDD) and Bipolar Disorder (BD), the latter not yet studied even though it was found strictly associated with MS. Methods: Cases: 201 consecutive-MS-patients. Controls: 804 sex-and-age-matched subjects without MS, randomly selected from an epidemiological database study. Psychiatric diagnoses according to DSM-IV were determined by physicians using structured interview tools (ANTAS-SCID). Bipolar Spectrum Disorders were identified by Mood Disorders Questionnaire (MDQ). QoL was measured by SF-12. Results: MS was the strongest determinant in worsening the QoL in the overall sample. Both MDD and BD type-II lifetime diagnoses were significantly associated with a poorer quality of life in the total sample as in cases of MS. In MS the impairment of the QoL attributable to BD type-II was even greater than that in MDD. Limitations: The MS diagnosis was made differently in cases and controls. Although this may have produced false negatives in controls, it would have reinforced the null hypothesis (no role of MS in worsening the QoL); therefore, it does not invalidate the study. Conclusions: MDD as well BD type-II are co-determinants in worsening QoL in MS. Clinicians should consider depressive symptoms as well as the hypomanic and mixed components in MS. Additional research is required to confirm our results and further clarify the manner in which BD and the mixed symptoms of BD type-II may affect awareness of both the underlying disease and psychiatric component and finally to what extent they impact treatment adherence with the available therapies for MS. & 2014 Elsevier B.V. All rights reserved. 1. Background

A simple, low-cost and easy scale-up technique for fabrication of conductive interconnects for flexible electronic devices is presented. A thin seed layer of nickel or copper was formed on the surface of PEN substrate via reactive inkjet printing of metal salt and reducing agent instead of traditional seed layers such as palladium nanoparticles and palladium or silver salts. For deposition of a uniform metal coating a polymer substrate patterned with the seed layer was immersed in an electroless plating bath. The electrical resistivity of deposited nickel–phosphorus and copper layers was 3.8±0.2 mΩ·cm and 29±2 µΩ·cm, respectively. The obtained structures possess excellent adhesion to polymeric substrates and reveal only slight decrease of conductivity after 20,000 bending cycles.

Thin epitaxial La 1− х K х MnO 3 films were grown using two-stage procedure. Influence of substitution of La 3+ ions with K + ions on the optical and electrical properties of La 1− x K x MnO 3 films ( х =0.05, 0.10, 0.15 и 0.18) has been studied in detail. A noticeable magnetorefractive effect in the films under study was detected in the infrared range. Magnetorefractive effect as well as transverse magneto-optical Kerr effect and magnetoresistance have the maximum in optimally doped sample with x =0.18 corresponding to the highest Curie temperature. The experimental data for compositions close to optimally doped films are in good agreement with the data calculated in the framework of a theory developed for manganites. The resonance-like contribution to magnetoreflection spectra of manganite films has been observed in the vicinity of the phonon bands. It is shown that magnetic and charge inhomogeneities strongly influence on the magneto-optical effects in films. Thin films of La 1− x K x MnO 3 with the large values of Kerr and magnetorefractive effect are promising magneto-optical material in the infrared range.