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The design of efficient helical pile structures is complicated because existing design standards lack clarity. In this work, we discuss a method for determining the ultimate bearing capacity of a pile using the screwing torque recorded during its sinking. The parameters of the corresponding correlation dependence and a method for determining the soil contact friction along the cylinder and tapered lateral surfaces of the screwed pile shaft were determined. [ABSTRACT FROM AUTHOR]

Cell migration plays an essential role in wound healing and inflammatory processes inside the human body. Peripheral blood neutrophils, a type of polymorphonuclear leukocyte (PMN), are the first cells to be activated during inflammation and subsequently migrate toward an injured tissue or infection site. This response is dependent on both biochemical signaling and the extracellular environment, one aspect of which includes increased temperature in the tissues surrounding the inflammation site. In our study, we analyzed temperature-dependent neutrophil migration using differentiated HL-60 cells. The migration speed of differentiated HL-60 cells was found to correlate positively with temperature from 30 to 42 °C, with higher temperatures inducing a concomitant increase in cell detachment. The migration persistence time of differentiated HL-60 cells was higher at lower temperatures (30–33 °C), while the migration persistence length stayed constant throughout the temperature range. Coupled with the increased speed observed at high temperatures, this suggests that neutrophils are primed to migrate more effectively at the elevated temperatures characteristic of inflammation. Temperature gradients exist on both cell and tissue scales. Taking this into consideration, we also investigated the ability of differentiated HL-60 cells to sense and react to the presence of temperature gradients, a process known as thermotaxis. Using a two-dimensional temperature gradient chamber with a range of 27–43 °C, we observed a migration bias parallel to the gradient, resulting in both positive and negative thermotaxis. To better mimic the extracellular matrix (ECM) environment in vivo, a three-dimensional collagen temperature gradient chamber was constructed, allowing observation of biased neutrophil-like differentiated HL-60 migration toward the heat source. [ABSTRACT FROM AUTHOR]

Previously, impulses were used to model abrupt changes in dynamic biological systems. This paper introduces a hybrid-index model that can characterize instantaneity of the impulsive behavior more effectively, compared with the existing impulsive Boolean network models. Using the hybrid-index model, we investigate the set stabilization of Boolean control networks with state-triggered impulses in the hybrid-domain and the time-domain. We establish necessary and sufficient conditions for set stabilizability in the hybrid and time domains, using the methods of k-domain and quotient mapping, respectively. Further, we obtain algorithms for constructing all hybrid-optimal and time-optimal set stabilizers by partitioning the state space into layers. The relationships between different set stabilizabilities are summarized. In addition, we have shared two examples to demonstrate the main results. [ABSTRACT FROM AUTHOR]

The Jin-Neelin model for the El Niño-Southern Oscillation (ENSO for short) is considered for which the authors establish existence and uniqueness of global solutions in time over an unbounded channel domain. The result is proved for initial data and forcing that are sufficiently small. The smallness conditions involve in particular key physical parameters of the model such as those that control the travel time of the equatorial waves and the strength of feedback due to vertical-shear currents and upwelling; central mechanisms in ENSO dynamics.From the mathematical view point, the system appears as the coupling of a linear shallow water system and a nonlinear heat equation. Because of the very different nature of the two components of the system, the authors find it convenient to prove the existence of solution by semi-discretization in time and utilization of a fractional step scheme. The main idea consists of handling the coupling between the oceanic and temperature components by dividing the time interval into small sub-intervals of length k and on each sub-interval to solve successively the oceanic component, using the temperature T calculated on the previous sub-interval, to then solve the sea-surface temperature (SST for short) equation on the current sub-interval. The passage to the limit as k tends to zero is ensured via a priori estimates derived under the aforementioned smallness conditions. [ABSTRACT FROM AUTHOR]

Alcohol dehydrogenases (ADHs), which belong to the oxidoreductase superfamily, catalyze the interconversion between alcohols and aldehydes or ketones with high stereoselectivity under mild conditions. ADHs are widely employed as biocatalysts for the dynamic kinetic resolution of racemic substrates and for the preparation of enantiomerically pure chemicals. This review provides an overview of biotechnological applications for ADHs in the production of chiral pharmaceuticals and fine chemicals. [ABSTRACT FROM AUTHOR]

We introduce an algorithm, called KarmaLego, for the discovery of frequent symbolic time interval-related patterns (TIRPs). The mined symbolic time intervals can be part of the input, or can be generated by a temporal-abstraction process from raw time-stamped data. The algorithm includes a data structure for TIRP-candidate generation and a novel method for efficient candidate-TIRP generation, by exploiting the transitivity property of Allen's temporal relations. Additionally, since the non-ambiguous definition of TIRPs does not specify the duration of the time intervals, we propose to pre-cluster the time intervals based on their duration to decrease the variance of the supporting instances. Our experimental comparison of the KarmaLego algorithm's runtime performance with several existing state of the art time intervals pattern mining methods demonstrated a significant speed-up, especially with large datasets and low levels of minimal vertical support. Furthermore, pre-clustering by time interval duration led to an increase in the homogeneity of the duration of the discovered TIRP's supporting instances' time intervals components, accompanied, however, by a corresponding decrease in the number of discovered TIRPs. [ABSTRACT FROM AUTHOR]

This paper is concerned with the convergence analysis of the horizontal method of lines for evolution equations of the parabolic type. Following a semidiscretization in time by $$S$$ -stage one-step methods, the resulting elliptic stage equations per time step are solved with adaptive space discretization schemes. We investigate how the tolerances in each time step must be tuned in order to preserve the asymptotic temporal convergence order of the time stepping also in the presence of spatial discretization errors. In particular, we discuss the case of linearly implicit time integrators and adaptive wavelet discretizations in space. Using concepts from regularity theory for partial differential equations and from nonlinear approximation theory, we determine an upper bound for the degrees of freedom for the overall scheme that are needed to adaptively approximate the solution up to a prescribed tolerance. [ABSTRACT FROM AUTHOR]

Posterior pedicle screw fixation is now the standard treatment for surgical correction of idiopathic scoliosis and has largely replaced anterior techniques, but there have been reports describing a lordogenic effect of segmental pedicle screw instrumentation in the thoracic spine. This clinical study compared anterior dual rod instrumentation with posterior pedicle screw fixation for idiopathic thoracic lordoscoliosis, including 42 patients (7 male, 35 female; average age 16 years, range 12-34) who underwent posterior pedicle screw fixation ( n = 20) or anterior dual rod instrumentation ( n = 22) at two centers. The average follow-up period was 33 months (24-108 months). Inclusion criteria were a diagnosis of adolescent idiopathic scoliosis with a structural thoracic curve (Lenke 1-3) and thoracic hypokyphosis (T4-T12 < 20°). The main thoracic curve magnitude and sagittal profile on standing radiographs were evaluated. Thoracic kyphosis was significantly restored from preoperatively 10.2° to 23.4° postoperatively in the anterior group and from 7.6° to 12.9° in the posterior group ( P < 0.005). Kyphosis improved significantly better in the anterior group than in the posterior group ( P < 0.005). The preoperative and postoperative main thoracic curve values were 63° (48-80°) and 25.2° in the anterior group and 60.6° (50-88°) and 23.6° in the posterior group, with no significant differences between the groups. No neurological or other severe complications were observed. Anterior dual rod instrumentation in patients with thoracic lordoscoliosis allows significantly better restoration of thoracic kyphosis than posterior pedicle screw instrumentation. [ABSTRACT FROM AUTHOR]

Littoral siliciclastic shallow marine horizontal conformable beds (a heterolithic succession), Middle to Late Miocene, outcropping in northeastern Argentina (Itizaingó Formation) and overlying transitional conformable horizontal regolithic mantle-rock bed derived from them (the Pampean and Post-Pampean Formations), were geochemically analyzed. The focus of this study is placed on the application of geochemical parameter and signature analyses related with the aforementioned geological units, which are of subcontinental extension into South America. The encountered results show an outstandingly similar geochemical behaviour between them. The main conclusion is that regolithic mantle-rock beds were derived from the littoral shallow marine mudstone (silty-argillaceous) beds. This is in oposition to previous aeolian processes proposed early in the 50's and later. These mudstone beds constitute important sections of the littoral shallow marine sequence beds (outcropping HST parasequence). Such regolitization proposed for the Pampean and Post-Pampean Formations predominantly developed in-situ during the Late Pleistocene and Holocene. The main erosional and mobilized agents were the surface free water (pluvial, fluvial and laminar water sheets) and vadose water. So, the wind flows and/or the immense air flow hurricanes are of insignificant sedimentological influence. Otherwise, there is not a proved appropiate sandy-silty reservoir for a reasonable support of the "aeolian hypothesis", as well as clear aeolian structures settled in the regolithic mantle-rock bed. In spite of these lines of equality textural-structural evidence, the geochemical values for both major elements and trace elements, demonstrate that the Miocene heterolithic marine succession was the mother rock of the overlying regolithic mantle-rock bed, which was formed as an in-situ mantle-rock bed. [ABSTRACT FROM AUTHOR]

A priori global identifiability deals with the (theoretical) uniqueness of solutions of model parameters from noise free input–output data. This issue is particularly critical when dealing with physiological systems where a different numerical estimate can distinguish a pathological state from a normal state. Recently, differential algebra tools have been applied to study identifiability of dynamic systems described by polynomial or rational equations. These methods are based on elimination theory for algebraic differential systems, the main tool being the computation of the so-called characteristic set of a differential ideal associated to the polynomials defining the dynamic system. This characteristic set can be found by symbolic computation and provides the so-called exhaustive summary of the model.The reparametrization of the input–output relation of the system by the exhaustive summary plays a major role not only in a priori identifiability but also in parameter estimation of nonlinear models. It is in fact a linear reparametrization and can be used to derive explicit one-shot least-squares estimates of the parameters. This allows to avoid the usual bottleneck of nonlinear parameter optimization which has to be performed by iterative optimization routines which are often unreliable, e.g. they give no guarantee of converging to a true minimum, and hence require time-consuming random search in the parameter space. Our algorithm has been tested in one- and two-dimensional Michaelis–Menten model where the choice of initial values of the parameters is critical since nonlinear least-squares minimization problem shows many local minima. Our method structurally has only one minimum and does not require initial values for the unknown parameters. However, when noise in the data is present, the optimization problem is highly ill-conditioned and the solution of the problem in the general case is still under study. [ABSTRACT FROM AUTHOR]

In this paper a spectral analysis methodology is introduced for stochastically sampled linear, dynamic, and stochastic continuous-time systems. This particular problem is considered for the purpose of investigating the spectral analysis issues associated with turbulent velocity measurements. The properties of the equivalent linear discrete-time system allow for the determination of the covariance between observations as a function of the number of in-between measurements. Subsequently, this autocovariance function is analyzed in the frequency domain. [ABSTRACT FROM AUTHOR]

In this paper we prove the existence of solutions of nonlinear equations of the type-div( a( x, u, Du)+H( x, u, Du)= f, where a and H are Caratheodory functions and f is a bounded Radon measure. We remark that the operator can be not coercive. We give also some regularity results. [ABSTRACT FROM AUTHOR]

We show that the tensor product of commutative Banach algebras possesses a finite universal Korovkin system, if and only if each of the factors does, and present an explicit construction of finite universal Korovkin systems for several commutative Banach algebras of vector-valued functions. The same questions are answered for the formation of direct sums and the passage to an ideal resp. its associated quotient algebra. [ABSTRACT FROM AUTHOR]

Sister chromatid exchanges (SCE) and structural chromosome aberrations were analyzed in peripheral blood lymphocytes of 100 individuals, and correlated to age and sex. No correlation was found between the frequency of SCE and age, but older individuals had significantly more structural aberrations than younger. Females had significantly more SCE as well as structural chromosome aberrations than males. The positive correlations of SCE and structural aberrations to age and sex were also significant when these factors, as well as smoking habits, were taken into consideration in an analysis of covariance. [ABSTRACT FROM AUTHOR]

The amount of alien chromatin introgressed in eight wheat/ Ae. longissima Pm13 recombinant lines, involving breakpoints on the short arms of wheat chromosomes 3B and 3D, was evaluated by cytogenetic and molecular approaches. For each line the residual homologous synaptic ability of the recombinant chromosome in its proximal wheat and distal alien portion was estimated through meiotic analyses. Subsequently, telocentric and RFLP mapping were used to assess the genetic distance from the wheat centromere to the wheat/ Ae. longissima breakpoints. One 3B recombinant line was distinguished from the other four by the chromosome pairing and telocentric mapping analyses. RFLP analysis succeeded in differentiating the remaining four lines into two groups. Chromosome pairing and telocentric mapping of the three 3D recombinant lines suggested that all had distinct breakpoints. However, the RFLP data could not discriminate between the two more proximal translocations. Physical locations for some RFLP loci were determined by a comparison of genotypes and C-banding karyotypes. This showed a considerable expansion of the genetic map compared to its physical length. [ABSTRACT FROM AUTHOR]

Linkage relationships were established between the secalin loci, Sec 1 (40-K gamma and omega secalins, homologous to the wheat gliadins) and Sec 3 (HMW = high-molecular-weight secalins, homologous to the wheat HMW glutenin subunits), and five chromosomal rearrangements involving chromosome 1R of rye ( Secale cereale L.). These were: interchanges T273W ( 1RL/5RS), T306W ( 1RS/5RL), and T850W ( 1RS/ 4RL), Robertsonian centromere split Rb1RW and the interchanged Robertsonian split Rb2R/248W. The analysis established the linkage relationships between the secalin loci and the breakpoints of the rearrangements, in addition to the quantitative effects of the rearrangements on the linkage. Sec-1 is located in the satellite at a position at least 2.5 cMorgan from the proximal border of the terminal C-band, and about 30 cMorgan from the nucleolar organizing region (NOR). The locus is also physically closer to the terminal C-band than to the NOR, but not as much as corresponds with the map distances. Similarly, the physical distance between Sec-3 and the centromere is greater than corresponds with the recombination frequency (0%-9%). Although overall recombination in 1RL remains the same, recombination between the centromere and Sec-3 is greatly reduced in the Robertsonian split combined with the interchange. This is not the case with the single Robertsonian split. [ABSTRACT FROM AUTHOR]

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