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Major updates to 1991 National Institutes of Health guidelines for bariatric surgery • Metabolic and bariatric surgery (MBS) is recommended for individuals with a body mass index (BMI) ≥35 kg/m2, regardless of presence, absence, or severity of co-morbidities. • MBS should be considered for individuals with metabolic disease and BMI of 30-34.9 kg/m2. • BMI thresholds should be adjusted in the Asian population such that a BMI ≥25 kg/m2 suggests clinical obesity, and individuals with BMI ≥27.5 kg/m2 should be offered MBS. • Long-term results of MBS consistently demonstrate safety and efficacy. • Appropriately selected children and adolescents should be considered for MBS. [ABSTRACT FROM AUTHOR]

• First study to assess native plant fitness in South African urban areas. • Nine native grassland plants are fit for Gauteng's urban climatic conditions. • Two forb species are less vulnerable to future climate change. Plants are essential components of urban microclimates, as they can help mitigate some of the adverse effects of urbanisation, enhance environmental quality, and thus contribute to overall species well-being and the sustainability of cities. Urban planners and policymakers often incorporate green infrastructure and urban greening into their strategies to create healthier and more livable urban environments. Plants are primary producers, serving as a baseline for the attraction and habitat of other species; they also provide vital ecosystem services, such as climate amelioration. Landscape designers and horticulturalists can influence plant selection through built environment interventions, increasing urban ecosystem services and benefits. Based on the evidence of native plant preferences by insects and people and their natural adaptation to regional climatic extremes, we tested, through an experimental study, the potential of native grassland plants to survive in assemblages in current urban environments. The study specifically monitored the tolerance of nine native grassland plant species to urban environments over six months in Gauteng, South Africa. A stratified random sampling was done by monitoring permanent quadrats in two purposefully engineered urban native gardens. Plant vitality was evaluated using chlorophyll a fluorescence. General climate data were obtained from a local weather station. Microclimatic temperature and humidity data were collected at each site and quadrat using Hygrochron High-Resolution Temperature and Humidity data loggers. The results indicated that all nine native plant species functioned with good photosynthetic health and can be recommended as resilient species that tolerate current urban conditions. Correlation studies indicated that two forb species, Haplocarpha lyrata and Scabiosa columbaria , showed great tolerance to current urban conditions. This vitality is likely contributed to their winter dormancy morphologically based on below-ground biomass, and their physiological adaptation to tolerate both wet and dry habitat conditions. This points to the potential of grassland forb species for urban use and the potential for climate adaptation in grassland areas. [ABSTRACT FROM AUTHOR]

The Kundelungu Plateau in the southeast of the Democratic Republic of the Congo (DRC) hosts numerous kimberlites, but up to now, only 34 bodies have been mapped. Locating these occurrences is hampered by the presence of sand cover on the plateau, a few tens of meters thick. Thus, most of the known pipes occur at the edge of the plateau where erosion has removed most of the sand cover. We report here on the Katuba kimberlite, a volcaniclastic kimberlite typical of a diatreme environment, with xenoliths of peridotite, carbonate, sandstone and shale, and lapilli-like microstructures. U-Pb analysis of perovskites from the Katuba kimberlite provides an age of 23 ± 1.8 Ma for the intrusion. Considering the age of 33 ± 4 Ma for perovskites from the Msipashi kimberlite pipe (also located on the same plateau), this new age suggests that the kimberlite magmatism in the Kundelungu Plateau lasted at least for 10 myr. The emplacement of these kimberlites is coeval with the opening of the Mweru graben, which is part of the East African Rift System (EARS), with structures oriented generally NW-SE and NE-SW. Some copper mineralisations inside the Katanga copperbelt, including those at Dikulushi and Kipushi, are located in similar structures, suggesting that the fluids responsible for the remobilisation of the mineralisation may be related to the kimberlite magmatism. Alternatively, the trigger for both the remobilisation of the mineralisation and the kimberlite magmatism is the tectonism that lead to the opening of the EARS. The upwelling of the asthenosphere or the mantle plume associated with the kimberlite magmatism may have supplied sufficient heat for fluid generation or contributed to the remobilisation of fluids. The location of the Katuba kimberlite along the NW-SE structures that were reactivated during the rifting inducing the opening of the Mweru graben, and which themselves are crosscut by the Luizi impact structure, provides another constraint on the relative age of the Luizi structure, which must be younger than the NW-SE structures and older than the emplacement of the Katuba kimberlite. • 44 perovskites from Katuba kimberlite provide an emplacement U-Pb age of 23 Ma. • The Kundelungu Plateau kimberlite magmatism lasted for a minimum of 10 m.y. • Luizi structure is older than this kimberlite magmatism and may be the trigger. • Heat source for mineralisation remobilisation is related to this magmatic activity. • The Katuba kimberlite is characteristic of a diatreme facies. [ABSTRACT FROM AUTHOR]

Charidotella ambita offers a unique opportunity for unambiguously locating its gold reflector by comparing the structure of reflecting and non-reflecting cuticle of the elytron and pronotum. Using light microscopy and TEM, the reflector was located underneath the macrofiber endocuticle just above the epidermis. The reflector is a multilayer comprising up to 50 bilayers alternating high and low density layers parallel to the surface of the cuticle. It is chirped, i.e., showing a progressive decrease in layer thickness from approximately 150 nm–100 nm across its depth. The high density layers in contact with the endocuticle fuse to the last macrofiber when the reflector is interrupted by a trabecula, demonstrating their cuticular nature. Simulated reflectance spectra from models of the multilayer matched the reflection spectra measured on the major gold patch of the elytron of living specimens. Previous reports in adult insects exhibiting metallic colors located their reflector in the upper strata and structures of the cuticle, i.e., epicuticle, exocuticle, scales and hairs. Thus, the endocuticular location of the reflector in C. ambita (and other tortoise beetles) appears unique for adult insects. Gold reflection appears in C. ambita only when the synthesis of the macrolayer endocuticle is complete, which may take up to 2 weeks. The development of the gold reflector coincides with the start of mating behavior, possibly suggesting a signaling function in conspecific recognition once sexual maturity has been reached. [ABSTRACT FROM AUTHOR]

Equivalent open chains generating the same motion as RC dyad with parallel axes are introduced based on equivalencies stemming from the algebraic structure of Lie group of the set of Euclidean displacements. These equivalent chains can be used to replace the RC limbs to deduce a family of RC // RC ― ― –like linkages. Cylindrical translation and exceptional mobility of 1-DoF translational linkages having RC limbs or equivalencies are revealed using the Lie-group property of the rigid-body displacement set. The intersections of two circular cylinders offer classification of various types of RC // RC ― ― linkages and the like. The discontinuous mobility of motion bifurcation in special RC // RC ― ― -like linkages is disclosed. General cases for the same phenomenon occur when an offset of translation displaces two RC subchains or equivalencies. At a singular posture of bifurcation, the coupler-bar locally has 2-DoF of infinitesimal translation and two working modes arise at the position of possible double point on the bicylindrical curve generated by two RC open sub-chains or equivalencies. Finally, the special case of Koenigs joint is described for the potential application in machinery. [ABSTRACT FROM AUTHOR]

The circular translation generated by a pseudo-planar parallelogram with four screw pairs having equal pitches and parallel axes is introduced and a special Delassus parallelogram producing the same motion is obtained through the addition of a second pseudo-planar parallelogram with another value of its equal pitches. A mechanical generator of spherical translation stemming from the circular translation generator is revealed. Combining a spherical translation generator and a pseudo-planar or special Delassus parallelogram leads to a new family of 6-screw (6H) paradoxical linkages with circular translation in a purely geometric way. Their architectural type belongs to the structural group with two alternate pairs of joint-axes parallel and one pair of opposite joint-axes parallel. Moreover, the one-degree-of-freedom (1-DoF) movability is conditioned by metric constraints. The already published 6R linkages having circular translation are special types of 6H with all screw-pitches zero. The parallel arrangement of three special 6R linkages produces a 3-UU parallel platform with circular translation (U denotes a universal joint with intersecting joint axes of revolute pairs). A more overconstrained m -UU case (m ≥ 4) with special joint-axes arrangements is disclosed too. [ABSTRACT FROM AUTHOR]

Background In patients with atrial fibrillation (AF), the autonomic nervous system is supposed to play an role in triggering AF; however, little is known of the effect on atrial conduction characteristics. Objective The purpose of this study was to study the effect of ganglionic plexus (GP) stimulation during sinus rhythm on atrial and pulmonary vein conduction in patients during thoracoscopic surgery for AF Methods In 25 patients, the anterior right ganglionic plexus (ARGP) was stimulated (16 Hz, at 1, 2, and 5 mA). Epicardial electrograms were recorded using a 48-electrode map from the right pulmonary vein (RPV) or right atrial (RA). Intra-atrial activation time (IAT), local activation time (LAT), and inhomogeneity of conduction (IIC) were determined. ECG parameters (P-P, P-R interval) were measured. Results P-P interval was 956 ± 157 ms (range 768–1368 ms), and P-R interval was 203 ± 37 ms (range 136–280 ms). After ARGP stimulation, a short-lasting increase of P-P interval was observed, more prominent at higher output (1 mA = 82 ms, 2 mA = 180 ms, 5 mA = 268 ms, all P <.01 vs baseline). P-R interval remained unchanged. IAT was 34.4 ms (range 5.6–50.3 ms) at the RA and 105.8 ms (range 79.7–163.3 ms) at the RPV. After 1-mA stimulation IAT increased, in patients taking beta-blockers ( P = .001), or it decreased, and this change persisted after subsequent stimulation at higher current (1 mA, P = .001; 2 mA, P = .401; 5 mA, P = .593). Similar changes were observed for LAT and IIC. Conclusion ARGP stimulation results in a short-lasting, output-dependent decrease in sinus node frequency due to a parasympathetic response. Stimulation of the ARGP induced a prolonged increase or decrease in conduction characteristics in patients with AF, consistent with a persistent differential parasympathetic and/or sympathetic response. [ABSTRACT FROM AUTHOR]

The dichloromethane/methanol (1:1) extract of the stem bark of Millettia usaramensis subspecies usaramensis was tested for its larvicidal activity against the 4th instar Aedes aegypti larvae and demonstrated activity with LC50 value of 50.8±0.06µg/mL at 48h. Compounds isolated from the extract were also tested for their larvicidal activities, and the rotenoid usararotenoid-A (LC50 4.3±0.8µg/mL at 48h) was identified as the most active principle. This compound appears to be the first rotenoid having a trans-B/C ring junction and methylenedioxy group at C-2/C-3 with high larvicidal activity. Related rotenoids with the same configuration at the B/C-ring junction did not show significant activity at 100µg/mL. [ABSTRACT FROM AUTHOR]

Abstract: Bricard one-DoF motion (abbreviated to BM) is a type of spatial motion in which all points of the moving body have spherical trajectories in the three-dimensional (3D) Euclidean space. This paper focuses on the mechanical realization of BM. The invariance characteristics and a visualization of three types of BM are provided in detail and the criterion for a possible full revolution is clarified too. The primitive Bricard motion generators (BMGs) are first proposed and geometrically verified. With the synthetic reasoning via the self-conjugation of any cylindrical 1-DoF motion and the invariance property of BM, two or more-loop BMGs are then synthesized systematically. These BMGs include isoconstrained mechanisms and overconstrained ones and the latter are exceptional and paradoxical chains. Besides, the platforms having BM, such as the Wren platform, LADD motion converter, algebraic screw joint, Griffis–Duffy (GD) type platform, etc. are clearly explained. A generalization of the GD platform and the general Verheyen-type mechanism with or without offset are newly revealed as well. [Copyright &y& Elsevier]

Highlights: [•] We consider the folded and unfolded SAW. [•] We show that these subsets are different for walks larger than 108 steps. [•] We detail the computational methods used to discover examples. [•] We present a tool for studying these subsets. [Copyright &y& Elsevier]

Abstract: A novel special motion called helical Cardan motion is introduced. The well known Cardanic motion is a special case with a zero pitch. A Cardan motion is a planar cycloidal motion, which can be produced by the internal rolling of a circle on a fixed circle whose diameter is twice the moving circle diameter. The newly studied motion is a combination of a Cardan motion with a helical motion. Any point lying on the surface of a cylinder having the smaller rolling circle as its cross section traces out a planar sinusoidal curve. Frame-free vector calculations are used to establish the essential properties of the special motion. Its corresponding characteristics are further utilized to make new derivations of related paradoxical chains, namely the new isosceles triangle HHHP chain, the HHHH rhomboid of Delassus and the two-loop Sarrus-type 6H-1P chain. A generalization of Sarrus'' mechanism for the generation of a rectilinear translational motion is derived as well. [Copyright &y& Elsevier]

Abstract: The product of two Schoenflies motion subgroups of the group of general displacements characterizes a noteworthy type of 5-dimensional (5D) displacement set called double Schoenflies or X–X motion. It includes any spatial translation and any two sequential rotations whose axes are parallel to two given independent vectors. The canonical irreducible representation of the 5D set of X–X motion is utilized to study various intersection sets of three distinct X–X motions. Three remarkable possibilities: 3-DoF translation motion, 3-DoF translation and 1-DoF infinitesimal rotation, and 3-DoF translation and 2-DoF infinitesimal rotation are discussed. Then we disclose the corresponding mechanisms with a mixture of finite and infinitesimal DoFs. Novel parallel mechanisms with 3-DoF finite translation and 2- or 1-DoF infinitesimal rotation are proposed. Parallel mechanisms whose infinitesimal mobility is specific of a singularity locus are derived, too. Meanwhile, it is established that the well-known SNU 3-UPU parallel manipulator with 3-DoF finite translation also has a mobility of 2-DoF infinitesimal rotation for a set of singular postures including its home configuration. [Copyright &y& Elsevier]

Background: Reduced expression of connexin43 (Cx43) and sodium channel (Nav1.5) and increased expression of collagen (fibrosis) are important determinants of impulse conduction in the heart. Objective: To study the importance and interaction of these factors at very low Cx43 expression, inducible Cx43 knockout mice with and without inducible ventricular tachycardia (VT) were compared through electrophysiology and immunohistochemistry. Methods: Cx43CreER(T)/fl mice were induced with tamoxifen and killed after 2 weeks. Epicardial activation mapping was performed on Langendorff-perfused hearts, and arrhythmia vulnerability was tested. Mice were divided into arrhythmogenic (VT+; n = 13) and nonarrhythmogenic (VT−; n = 10) animals, and heart tissue was analyzed for Cx43, Nav1.5, and fibrosis. Results: VT+ mice had decreased Cx43 expression with increased global, but not local, heterogeneity of Cx43 than did VT− mice. Nav1.5-immunoreactive protein expression was lower in VT+ than in VT− mice, specifically at sites devoid of Cx43. Levels of fibrosis were similar between VT− and VT+ mice. QRS duration was increased and epicardial activation was more dispersed in VT+ mice than in VT− mice. The effective refractory period was similar between the 2 groups. Premature stimulation resulted in a more severe conduction slowing in VT+ than in VT− hearts in the right ventricle. Separate patch-clamp experiments in isolated rat ventricular myocytes confirmed that the loss of Cx43 expression correlated with the decreased sodium current amplitude. Conclusions: Global heterogeneity in Cx43 expression and concomitant heterogeneous downregulation of sodium-channel protein expression and sodium current leads to slowed and dispersed conduction, which sensitizes the heart for ventricular arrhythmias. [Copyright &y& Elsevier]

Abstract: To improve the treatments for low back pain, new designs of total disk replacement have been proposed. The question is how well these designs can act as a functional replacement of the intervertebral disk. Four finite element models were made, for four different design concepts, to determine how well they can mimic the physiological intervertebral disk mechanical function. The four designs were a homogenous elastomer, a multi-stiffness elastomer, an elastomer with fiber jacket, and a hydrogel with fiber jacket. The best material properties of the four models were determined by optimizing the model behavior to match the behavior of the intervertebral disk in flexion–extension, axial rotation, and lateral bending. It was shown that neither a homogeneous elastomer nor a multi-stiffness elastomer could mimic the non-linear behavior within the physiological range of motion. Including a fiber jacket around an elastomer allowed for physiological motion in all degrees of freedom. Replacing the elastomer by a hydrogel yielded similar good behavior. Mimicking the non-linear behavior of the intervertebral disk, in the physiological range of motion is essential in maintaining and restoring spinal motion and in protecting surrounding tissues like the facet joints or adjacent segments. This was accomplished with designs mimicking the function of the annulus fibrosus. [Copyright &y& Elsevier]

Abstract: Based on the geometric properties of the oblique circular or elliptic cylinder and an invariant subset of translations, a family of related chains having a paradoxical mobility is systematically synthesized. First of all, vector calculation is used to describe the plane symmetry operation. The plane symmetry property of an oblique circular (OC) cylinder, which has circular directrices, is verified. Next, we introduce a mechanical generator of 2-DoF translation along the surface of an OC cylinder and derive a novel PaPPa paradoxical chain, where Pa denotes the composite joint of a 4-R hinged parallelogram with parallel axes. Then, we establish its corresponding chain. The implementation of pseudo-planar and Delassus parallelograms leads to more general chains of type PHPPH, where PH designates the composite joint of a 4-H parallelogram with four parallel axes. The related chain having two couples of H pairs with parallel axes and equal pitches separately is a new 1-DoF paradoxical linkage. [Copyright &y& Elsevier]

The evaluation of the biocidal activity of the fruit of Solanum sisymbriifolium involving non target organisms such as aquatic insects, fish and snails lead to the isolation of the steroidal alkaloids, solamargine and β-solamarine, from the active fractions. The fractions A3 and C, with biological activity against fish, snail and aquatic insect and larvae, are able to affect the good functioning of ecosystem found on alimentary chain. The fraction B seems to be less toxic to fish and aquatic insect and larvae. The fraction B could thus be used as molluscicide in the future. [Copyright &y& Elsevier]

Abstract: Schoenflies motion is often termed X-motion for conciseness. A set of X-motions with a given direction of its axes of rotations has the algebraic properties of a Lie group for the composition product of rigid-body motions or displacements. The product of two X-subgroups, which is the mathematical model of a serial concatenation of two kinematic chains generating two distinct X-motions, characterizes a noteworthy type of 5-dimensional (5D) displacement set called double Schoenflies motion or X–X motion for brevity. This X–X motion set is a 5D submanifold of the displacement 6D Lie group. Such a motion type includes any spatial translation (3T) and any two sequential rotations (2R) provided that the axes of rotation are parallel to two fixed independent vectors. This motion set also contains the rotations that are products of the foregoing two rotations. In the paper, some preliminary fundamentals on the 4D X-motion are recalled; the 5D set of X–X motions is emphasized. Then implementing serial arrays of one-dof Reuleaux pairs and hinged parallelograms, we enumerate all serial mechanical generators of X–X motion, which have no redundant internal mobility. Based on the group-theoretic concepts, one can differentiate two families of irreducible representations of an X–X motion. One family is realized by twenty-one open chains including the doubly planar motion generators as special cases. The other is generally classified into eight major categories in which one hundred and six distinct open chains generating X–X motion are revealed and nineteen more ones having at least one parallelogram are derived from them. Meanwhile, these kinematic chains are graphically displayed for a possible use in the structural synthesis of parallel manipulators. [Copyright &y& Elsevier]

Abstract: In this paper, we focus on some examples of practical applications of the primitive Schönflies-motion generators that are named also the primitive X-motion generators for conciseness. We address especially the serial SCARA-type robots and the 3-dof translational parallel manipulators. Based on the limb architectures of primitive X-motion generators, we systematically introduce general architectures of serial or parallel manipulators for the purpose of practical applications. The brief account of various achievements of some of the X-motion generators that are already described in the recent literature is also proposed and their obviously singular postures are preliminarily obtained. [Copyright &y& Elsevier]

Abstract: A noteworthy type of motion called Schoenflies motion and often termed X-motion for brevity is presented. A specified set of X-motions is endowed with the algebraic structure of a four-dimensional (4D) Lie group. This 4D displacement Lie subgroup includes any translation and any rotation provided that the axis of rotation is parallel to a given direction. In the paper, some preliminary fundamentals about the Lie group of displacements are recalled; the 4D Lie subgroup of X-motion is emphasized. Then serial concatenations of one-dof Reuleaux pairs and hinged parallelograms lead to the enumeration of all possible general architectures of mechanical generators for a given X subgroup. Meanwhile, their corresponding embodiments are graphically displayed for a future use in the structural synthesis of parallel manipulators. These generators are sorted into four classes based on the number of prismatic pairs. In total, forty-three distinct mechanical generators of X-motion are revealed and eighty-two ones having at least one parallelogram are also derived from them. Some chains that are defective generators of X-motion are also identified through an approach based on the group dependency. [Copyright &y& Elsevier]

Abstract: This paper presents an incremental learning algorithm for feed-forward neural networks used as approximators of real world data. This algorithm allows neural networks of limited size to be obtained, providing better performances. The algorithm is compared to two of the main incremental algorithms (Dunkin and cascade correlation) in the respective contexts of synthetic data and of real data consisting of radiation doses in homogeneous environments. [Copyright &y& Elsevier]

Embryonic stem (ES) cells and embryonal carcinoma (EC) cells express high amounts of functional connexin43 (Cx43). During mesoderm formation and subsequent cardiac differentiation, Cx43 is initially down-regulated but is up-regulated again as the emerging cardiomyocytes mature. In this study, we investigated the regulation of Cx43 expression during early phases of differentiation in F9 and P19 EC cells. We found a striking inverse correlation between the expression of Cx43 and that of the transcriptional repressor Snail1. No clear relationship was found with Smad-interacting-protein1 (SIP1), another transcription factor inducing epithelium-to-mesenchyme transition (EMT). Promoter-reporter assays indicated Cx43 repression at the promoter level by ectopically expressed Snail1. To establish whether the Cx43 down-regulation depends on endogenous Snail1, MES-1 cells, differentiated derivatives of P19 EC, were stably transfected by an siRNA construct silencing Snail1 expression. This resulted in a mesenchyme-to-epithelium transition, which was accompanied by increased levels of Cx43 mRNA and protein and enhanced metabolic and electrical coupling. We conclude that Snail1-mediated EMT results in a Cx43 repression. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a dynamical study of an imaginary Bragg grating. It shows that when the lasing threshold is reached, the standard transmission matrix approach is no longer valid and a more comprehensive model taking in account gain saturation is required. The grating has then been studied using a direct numerical solution of the time-dependant coupled-mode equations including gain saturation effects. This description is valid for analyzing imaginary Bragg gratings operating both below and above the lasing threshold, and it has demonstrated to provide a physically consistent solution, avoiding the group delay divergences and abnormalities which are predicted by the transfer-matrix model. [Copyright &y& Elsevier]

The susceptibility of planktonic and biofilm cells of Pseudomonas marginalis toward four commonly used biocides at different temperatures (15 and 30°C) and biofilm growth times (24 and 48 h) was assessed. Using the MBEC biofilm device, biofilm production in maple sap was shown to be highly reproducible for each set of conditions tested. Biofilm formation was influenced by growth temperature and time. A temperature of 15°C and incubation time of 24 h yielded fewer CFU per peg and showed fewer adhered cells and typical biofilm structures, based on scanning electron microscopy observations as com- pared with other conditions. Minimal biofilm eradication concentration values for P. marginalis were significantly greater (P < 0.001) than were MBCs for planktonic cells and for every biocide tested, with the exception of minimal biofilm eradication concentration values for peracetic acid at 15°C and 24 h. Sodium hypochlorite and peracetic acid sanitizers were able to eliminate P. marginalis biofilms at lower concentrations as compared with hydrogen peroxide- and quaternary ammonium-based sanitizers (P < 0.001). According to the results obtained, sodium hypochlorite and peracetic acid sanitizers would be more appropriate for maple sap collection system sanitation. [ABSTRACT FROM AUTHOR]

Abstract: The bacterial microflora of maple sap and biofilms in collection system tubing were studied through the use of bacterial counts, scanning electron microscopy (SEM) of surfaces and the analysis of 16S rRNA gene by denaturing gradient gel electrophoresis (DGGE). Samples were taken at five times during the 2002 and 2003 seasons in order to follow the changes in the microflora of this complex ecosystem. Bacterial counts showed the growth of bacterial populations as the season advanced. These populations were mainly composed of psychrotrophic bacteria and Pseudomonas spp. SEM results confirmed the suspected presence of biofilms on the inner surfaces of tubing samples. Bacterial colonization and biofilm formation progressively increased during the season for both lateral and main line surfaces, and biofilms were mainly composed of rod shape bacteria. The bacterial microflora profiles obtained for sap and corresponding biofilm by DGGE showed up to 12 major bands. The Shannon-Weaver index of diversity (H) calculated from DGGE bands were statistically higher for sap samples compared to biofilm. The diversity index was relatively stable or increasing for lateral line sap and biofilm samples during the season while the diversity index for sap and biofilm samples of the main line showed a decreasing profile as the season progressed. Sequence analysis of major DGGE bands revealed the predominance of bacteria from the genera Pseudomonas, Rahnella and another, unidentified genus. The results describe the composition of sap collection system microflora as well as the formation of biofilms and will be useful for further studies on factors affecting maple product quality. [Copyright &y& Elsevier]

Abstract: The paper introduces four families of three-DOFs translational-rotational Parallel-Kinematics Mechanisms (PKMs) as well as the mobility analysis of such families using Lie group theory. Two of these families are mechanisms with one-rotational two-translational degrees of freedom (DOFs) and each of the other two has one-translational two-rotational DOFs. Four novel mechanisms are presented and discussed as representatives of these four families. Although these mechanisms are asymmetric, the components used to realise them are very similar and, hence, there is no great departure from the favourable modularity of parallel-kinematics mechanisms. [Copyright &y& Elsevier]

Abstract: Based on the Lie-group-algebraic properties of the displacement set, the 3-dof generators of planar gliding motion ( G ) are introduced. Two serial generators of 3-dof planar gliding produce a 5-dof motion including 3 translations and 2 rotations (3T–2R) as it is established using the composition product of two Lie subgroups of G -motion. All possible 3T–2R 5-dof limbs generating double-planar ( G – G ) kinematic bonds are comprehensively enumerated. There are a total of 21 mechanical generators of G – G motion with distinct architectures. The parallel setting of three 5-dof G – G limb make up a translational parallel manipulator (TPM), which produces a motion subset of spatial translations. Moreover, related families of TPMs are also deducted using the commutation of factors in any products of spatial translations and rotations around an axis. By that way, some novel examples of 3-dof TPM including doubly planar kinematic chains are synthesized systematically. [Copyright &y& Elsevier]

Abstract: The paper deals with the structural synthesis of asymmetrical non-overconstrained 3-dof spherical parallel mechanisms (SPM). Most of SPM described in the literature are composed of three identical limbs, and they can be called symmetrical SPM. New SPM composed of three structurally distinct limbs, which we name asymmetrical SPM, are disclosed. This paper addresses the type synthesis of asymmetrical non-overconstrained SPM. Firstly, a mobility analysis is presented in order to find the degree of freedom of the limbs. In a second step the geometrical conditions of the limb assembly that achieves the spherical motion are established. Finally, limb architectures of asymmetrical non-overconstrained SPM are enumerated. The resulting kind of scientific catalogue is comprehensive under the hypothesis of non-paradoxical mobility. Moreover SPM 4-dof limbs without idle pairs were never revealed before. [Copyright &y& Elsevier]

Cortical bone has two systems of interconnected channels. The largest of these is the vascular porosity consisting of Haversian and Volkmann''s canals, with a diameter of about 50 μm, which contains a.o. blood vessels and nerves. The smaller is the system consisting of the canaliculi and lacunae: the canaliculi are at the submicron level and house the protrusions of the osteocytes. When bone is differentially loaded, fluids within the solid matrix sustain a pressure gradient that drives a flow. It is generally assumed that the flow of extracellular fluid around osteocytes plays an important role not only in the nutrition of these cells, but also in the bone''s mechanosensory system.The interaction between the deformation of the bone matrix and the flow of fluid can be modelled using Biot''s theory of poroelasticity. However, due to the inhomogeneity of the bone matrix and the scale of the porosities, it is not possible to experimentally determine all the parameters that are needed for numerical implementation. The purpose of this paper is to derive these parameters using composite modelling and experimental data from literature. A full set of constants is estimated for a linear isotropic description of cortical bone as a two-level porous medium. Bone, however, has a wide variety of mechanical and structural properties; with the theoretical relationships described in this note, poroelastic parameters can be derived for other bone types using their specific experimental data sets. [Copyright &y& Elsevier]

Focuses on the effects of 1,25-dihydroxyvitamin D3 and analogue, 1,25-dihydroxy-16ene-vitamin D3, on T helper subsets type 1 (Th1) or type 2 (Th2) that have distinctive functional characteristics in humans. Th1 and Th2 secretions; Sterol; Spontaneous autoimmunity.

Mechanotransduction is the initiation of an electrochemical signal as a result of mechanical stimuli. It is found predominately in biological tissue and its mechanisms are well documented. In the gel like tissues of the body, such as articular cartilage and intervertebral discs, mechanotransduction regulates matrix building and degrading processes as well as keeping the tissues adequately hydrated, both with the aim of minimizing degradation. The electrochemical responses to mechanical loading at constant volume of an inanimate hydrogel could assist in the understanding of these processes. There is considerable evidence that the modulus of hydrated tissues and hydrogels depend explicitly on ionic concentration. By modeling the mechano-electrochemical relationship of a hydrogel, the coupling of the elastic and electrochemical energies can be quantified. In turn, the mechanisms that govern this phenomenon can be better understood. This study modifies the Flory-Rehner theory of gels, using material-specific experimental data as input. The results show up to a 11% difference in equilibrium swelling magnitude compared to the Flory-Rehner model. Furthermore, under isochoric deformation, an increase in electrical potential is shown with increasing shear strain, something which is not possible with conventional Flory-Rehner and Donnan theory. This aligns the continuum model presented here more closely with both experiment and microscopic theories. The mechanosensing capabilities as well as varying swelling responses in different solution concentrations highlight the models potential applications in both biological and technological settings. Unlabelled Image • A mechano-electrochemical material model for hydrogels was derived. • Mechanical loading changes the electrical potential at constant volume. • The modulus changes effect hydrogel swelling magnitude at different concentrations. • The results indicate potential applications in biology and technology. [ABSTRACT FROM AUTHOR]