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In Mimosa pudica plants, local and global responses to environmental stimuli are associated with different types of electrical activity. Non-damaging stimuli (e.g. cooling) generate action potentials (APs), whereas damaging stimuli (e.g. heating) are associated with variation potentials (VPs). Local cooling of Mimosa branches resulted in APs that propagated up to the branch-stem interface and caused drooping of the branch (local response). This electrical activation did not pass the interface. If the branch was triggered by heat, however, a VP was transferred to the stem and caused activation of the entire plant (global response). VPs caused by heat were always preceded by APs and summation of the two types of activation appeared to be necessary for the activation to pass the branch-stem interface. Mechanical cutting of leaves also resulted in VPs preceded by APs, but in those cases a time delay was present between the two activations, which prevented adequate summation and transmission of activation. Simultaneous cold-induced activation of a branch and the stem below the interface occasionally resulted in summation sufficient to activate the stem beyond the interface. To investigate the effect of activation delay on summation, a similar structure of excitable converging pathways, consisting of a star-shaped pattern of neonatal rat heart cells, was used. In this model, summation of activation was not hindered by a small degree of asynchrony. The observations indicate that summation occurs in excitable branching structures and suggest that summation of activation plays a role in the propagation of nocuous stimuli in Mimosa. [ABSTRACT FROM AUTHOR]

Trees in an urban setting, such as the exotic Oak (Quercus robur L.) trees in Potchefstroom (North West Province, South Africa), provide several ecosystem services on tree, street and city level. Since urban trees are very favourable to urban life, it is pivotal to study their health and conserve these trees as long as possible. Quercus robur trees in the historic Oak Avenue in this city have been showing a visual decrease in vitality since 1980, the cause of which is still largely unknown. This study aimed to determine the vitality of a section of the trees in the avenue with different types of surrounding soil cover by determining visual tree conditions and measuring leaf water potential, nutrient analysis and chlorophyll a fluorescence. Data obtained indicated that the parameters and indicators used to determine tree vitality were of value in determining plant health; however, this data alone does not account for the decline in the health of the trees. Though trees with impenetrable surfaces as soil cover under the trees, i.e. "sealed soil", showed lower water potentials, this nevertheless is not indicative of a water deficit. Other factors should be considered as the cause of the decline in the vitality of these street trees. Oak trees in the avenue in Potchefstroom should be monitored carefully in future to ensure successful conservation by scientists, residents of the city and the municipal authorities. [ABSTRACT FROM AUTHOR]

It is vital to enumerate the geographical distribution of future rainfall regimes to better manage rain-fed systems. These studies have shown that the resultant changes in extreme rainfall events are sensitive to the topography of the region and vary according to the type of model used, as well as the global warming scenario considered (Diallo I et al., i 2015; Fotso-Nguemo I et al., i 2018; Sonkoué I et al., i 2019). For instance, the results for Central Africa have revealed that, for both high and low greenhouse gas (GHG) emission scenarios, the projected changes in the distribution of heavy rainfall over this region will be more intense both in terms of rainfall amount and intensity (Pokam I et al., i 2018; Sonkoué I et al., i 2019; Fotso-Nguemo I et al., i 2019). In Cameroon, remotely sensed rainfall data and ground-based observation network studies that provided first-hand descriptive records of rainfall began a few decades and a century ago, respectively. [Extracted from the article]

Objective: Sex steroid hormones like estrogens have a key role in the regulation of energy homeostasis and metabolism. In transwomen, gender-affirming hormone therapy like estradiol (in combination with antiandrogenic compounds) could affect metabolism as well. Given that the under lying pathophysiological mechanisms are not fully understood, this study assessed circulating estradiol-driven microRNAs (miRs) in transwomen and their regulation of genes involved in metabolism in mice. Methods: Following plasma miR-sequencing (seq) in a transwomen discovery (n = 20) and validation cohort (n = 30), we identified miR-224 and miR-452. Subsequent systemic silencing of these miRs in male C57Bl/6 J mice (n = 10) was followed by RNA-seq-based gene expression analysis of brown and white adipose tissue in conjunction with mechanistic studies in cultured adipocytes. Results: Estradiol in transwomen lowered plasma miR-224 and -452 carried in extracellular vesicles (EVs) while their systemic silencing in mice and cultured adipocytes increased lipogenesis (white adipose) but reduced glucose uptake and mitochondrial respiration (brown adipose). In white and bro wn adipose tissue, differentially expressed (miR target) genes are associated with lipogenesis (white adipose) and mitochondrial respiration and glucose uptake (brown adipose). Conclusion: This study identified an estradiol-drive post-transcriptional n etwork that could potentially offer a mechanistic understanding of metabolism following gender-affirming estradiol therapy. [ABSTRACT FROM AUTHOR]

Though several countries have adopted the sexual violence law which criminalizes child marriage, the practice of early marriage persists in Sub-Saharan Africa. This paper examined the socio-economic and demographic determinants of early marriage among young women in four Sub-Saharan African (SSA) countries, namely Niger, Democratic Republic of Congo, Mali and Malawi. Descriptive and multivariate analyses were performed to show that young women without formal education have 1.62, 1.59, 1.55 and 2.08 times more risk of early union than their secondary or higher educated counterparts. The study recommends the implementation of a universal, free and compulsory basic education in SSA countries. [ABSTRACT FROM AUTHOR]

Background: Revisional bariatric surgery (RBS) constitutes a possible solution for patients who experience an inadequate response following bariatric surgery or significant weight regain following an initial satisfactory response. This paper reports results from the first modified Delphi consensus-building exercise on RBS.Methods: We created a committee of 22 recognised opinion-makers with a special interest in RBS. The committee invited 70 RBS experts from 27 countries to vote on 39 statements concerning RBS. An agreement amongst ≥ 70.0% experts was regarded as a consensus.Results: Seventy experts from twenty-seven countries took part. There was a consensus that the decision for RBS should be individualised (100.0%) and multi-disciplinary (92.8%). Experts recommended a preoperative nutritional (95.7%) and psychological evaluation (85.7%), endoscopy (97.1%), and a contrast series (94.3%). Experts agreed that Roux-Y gastric bypass (RYGB) (94.3%), One anastomosis gastric bypass (OAGB) (82.8%), and single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) (71.4%) were acceptable RBS options after gastric banding (84.3%). OAGB (84.3%), bilio-pancreatic diversion/duodenal switch (BPD/DS) (81.4%), and SADI-S (88.5%) were agreed as consensus RBS options after sleeve gastrectomy. lengthening of bilio-pancreatic limb was the only consensus RBS option after RYGB (94.3%) and OAGB (72.8%).Conclusion: Experts achieved consensus on a number of aspects of RBS. Though expert opinion can only be regarded as low-quality evidence, the findings of this exercise should help improve the outcomes of RBS while we develop robust evidence to inform future practice. [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]

Uncovering the genomic basis of climate adaptation in traditional crop varieties can provide insight into plant evolution and facilitate breeding for climate resilience. In the African cereal sorghum (Sorghum bicolor L. [Moench]), the genomic basis of adaptation to the semiarid Sahelian zone versus the subhumid Soudanian zone is largely unknown. To address this issue, we characterized a large panel of 421 georeferenced sorghum landrace accessions from Senegal and adjacent locations at 213,916 single‐nucleotide polymorphisms (SNPs) using genotyping‐by‐sequencing. Seven subpopulations distributed along the north‐south precipitation gradient were identified. Redundancy analysis found that climate variables explained up to 8% of SNP variation, with climate collinear with space explaining most of this variation (6%). Genome scans of nucleotide diversity suggest positive selection on chromosome 2, 4, 5, 7, and 10 in durra sorghums, with successive adaptation during diffusion along the Sahel. Putative selective sweeps were identified, several of which colocalize with stay‐green drought tolerance (Stg) loci, and a priori candidate genes for photoperiodic flowering and inflorescence morphology. Genome‐wide association studies of photoperiod sensitivity and panicle compactness identified 35 and 13 associations that colocalize with a priori candidate genes, respectively. Climate‐associated SNPs colocalize with Stg3a, Stg1, Stg2, and Ma6 and have allelic distribution consistent with adaptation across Sahelian and Soudanian zones. Taken together, the findings suggest an oligogenic basis of adaptation to Sahelian versus Soudanian climates, underpinned by variation in conserved floral regulatory pathways and other systems that are less understood in cereals. [ABSTRACT FROM AUTHOR]

Objectives: Respiratory syncytial virus (RSV) infection causes morbidity and mortality in cancer patients. However, studies describing this infection in patients with haematological malignancies are scarce. We sought to evaluate the clinical impact of RSV infection on this patient population.Methods: We reviewed the records of patients with haematological malignancies and RSV infections cared for at our institution between January 2000 and March 2013.Results: Of the 181 patients, 71 (39%) had AML, ALL or myelodysplastic syndrome, 12 (7%) had CML or CLL, 4 (2%) had Hodgkin lymphoma, 35 (19%) had non-Hodgkin lymphoma and 59 (33%) had multiple myeloma. Most patients [117 (65%)] presented with an upper respiratory tract infection (URTI) and 15 (13%) had a subsequent lower respiratory tract infection (LRTI). The overall LRTI rate was 44% and the 90 day mortality rate was 15%. Multivariable regression analysis showed that having both neutropenia and lymphocytopenia (adjusted OR = 7.17, 95% CI = 1.94-26.53, P < 0.01) and not receiving ribavirin-based therapy during RSV URTI (adjusted OR = 0.03; 95% CI = 0.01-0.11, P < 0.001) were independent risk factors for LRTI. Having both neutropenia and lymphocytopenia at RSV diagnosis was also a risk factor for death at 90 days after RSV diagnosis (adjusted OR = 4.32, 95% CI = 1.24-15.0, P = 0.021).Conclusions: Patients with haematological malignancies and RSV infections, especially those with immunodeficiency, may be at risk of LRTI and death; treatment with ribavirin during RSV URTI may prevent these outcomes. [ABSTRACT FROM AUTHOR]

The cause of a measured −1.4-dB dip at 80 GHz in a silicon capacitor was investigated and determined to be the primary resonance of the integrated metal seal ring (SR) enclosing the component. Specifically, the proximity of a capacitor electrode to the SR was found to activate two parasitic, parallel, and open-circuited coplanar strip transmission lines (TLs), each having their ${\lambda /2}$ resonance at this frequency. This model was confirmed with 3-D finite-element method electromagnetic simulations and measurements of modified SRs. Building on the proposed TL interpretation of the problem, an ultra-broadband equivalent circuit model was developed for such capacitors, successfully replicating the measured SR resonance. Then, the fundamental resonance frequency and related quality factor of various-sized integrated metal SRs were accurately predicted. Finally, potential solutions to damp or cancel such parasitic resonances were investigated. Although cutting the SR at selected locations to disable the parasitic lines was experimentally proven to be successful, damping the parasitic signal with highly doped silicon is found to be the best option in terms of effectiveness and practical implementation. Novel solutions, analogous to the use of radio frequency terminations, were also tested. This paper, to the best of our knowledge, is the first extensive characterization of parasitic resonance afflicting electronics enclosed by an integrated metal SR. The analysis, equivalent circuit model, and solutions reported here can be directly applied to arrays of components or circuits, and are scalable to any device size and operating frequency. [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]

In this paper, we explain why the chaotic mutation (CM) model of J. M. Bahi and C. Michel (2008) simulates the genes mutations over time with good accuracy. It is firstly shown that the CM model is a truly chaotic one, as it is defined by Devaney. Then, it is established that mutations occurring in genes mutations have indeed a same chaotic dynamic, thus making relevant the use of chaotic models for genomes evolution. Transposition and inversion dynamics are finally investigated. [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]

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]

Introduction: Antiretroviral therapy (ART) has been successful at decreasing the morbidity and mortality associated with human immunodeficiency virus type 1 (HIV-1) infection. HIV-1 drug resistance (HIVDR) among ART-naive patients has been documented to compromise the success of initial therapy. This study was conducted to determine the prevalence of HIVDR mutations among newly diagnosed drug-naive HIV-infected individuals in Lebanon. Methodology: Plasma samples from 37 newly diagnosed participants at various stages of HIV-1 infection were used to determine HIV-1 RNA viral load, isolate viral RNA, and amplify DNA by RT-PCR. Purified PCR products were used to perform genotypic resistance tests. Results: The prevalence of resistance mutations to nucleoside reverse transcriptase inhibitors (NRTI), non-nucleoside reverse transcriptase inhibitors (NNRT), and protease inhibitors (PI) were 5.4%, 10.8%, and 8%, respectively. The major mutations detected in the study participants conferred resistance to NRTIs and NNRTIs recommended for HIV-1 treatment. No significant relationship between HIV-1 viral load of participants and the mode of HIV-1 transmission or between the occurrence of HIVDR and the mode of transmission was found. Conclusions: To our knowledge, this is the first study on HIVDR mutations among newly diagnosed HIV-infected persons in Lebanon. The overall prevalence of HIVDR mutations detected in our study was 16%. Our results are important for evaluating the utility of the standard first-line regimens in use, determining the feasibility of HIVDR testing before the initiation of ART, as well as minimizing the emergence and transmission of HIVDR. [ABSTRACT FROM AUTHOR]

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]

Highlights: [•] Measurement of in vitro release characteristics of morphine from a P407 based gel. [•] Measurement was done with a dissolution cell. [•] The morphine release from the P407 based gel followed zero-order kinetics. [•] The constant release from the P407 based gel was 150μgcm−2 h−1. [ABSTRACT FROM AUTHOR]

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]

This research work presents a new class of non-blind information hiding algorithms that are stego-secure and robust. They are based on some finite domains iterations having the Devaney's topological chaos property. Owing to a complete formalization of the approach, we prove security against watermark-only attacks of a large class of steganographic algorithms. Finally a complete study of robustness is given in frequency DWT and DCT domains. [ABSTRACT FROM AUTHOR]

There is a growing interest in the use of video sensor networks in surveillance applications in order to detect intruders with low cost. The essential concern of such networks is whether or not a specified target can pass or intrude the monitored region without being detected. This concern forms a serious challenge to wireless video sensor networks of weak computation and battery power. In this paper, our aim is to prolong the whole network lifetime while fulfilling the surveillance application needs. We present a novel scheduling algorithm where only a subset of video nodes contributes significantly to detect intruders and prevent malicious attacker to predict the behavior of the network prior to intrusion. Our approach is chaos based, where every node based on its last detection, a hash value and some pseudorandom numbers easily compute a decision function to go to sleep or active mode. We validate the efficiency of our approach through theoretical analysis and demonstrate the benefits of our scheduling algorithm by simulations. Results show that in addition to being able to increase the whole network lifetime and to present comparable results against random attacks (low stealth time), our scheme is also able to withstand malicious attacks due to its fully unpredictable behavior. [ABSTRACT FROM AUTHOR]

Down syndrome (DS) leads to complex phenotypes and is the main genetic cause of birth defects and heart diseases. The Ts65Dn DS mouse model is trisomic for the distal part of mouse chromosome 16 and displays similar features with post-natal lethality and cardiovascular defects. In order to better understand these defects, we defined electrocardiogram (ECG) with a precordial set-up, and we found conduction defects and modifications in wave shape, amplitudes, and durations in Ts65Dn mice. By using a genetic approach consisting of crossing Ts65Dn mice with Ms5Yah mice monosomic for the App-Runx1 genetic interval, we showed that the Ts65Dn viability and ECG were improved by this reduction of gene copy number. Whole-genome expression studies confirmed gene dosage effect in Ts65Dn, Ms5Yah, and Ts65Dn/Ms5Yah hearts and showed an overall perturbation of pathways connected to post-natal lethality (Coq7, Dyrk1a, F5, Gabpa, Hmgn1, Pde10a, Morc3, Slc5a3, and Vwf) and heart function (Tfb1m, Adam19, Slc8a1/Ncx1, and Rcan1). In addition cardiac connexins (Cx40, Cx43) and sodium channel sub-units (Scn5a, Scn1b, Scn10a) were found down-regulated in Ts65Dn atria with additional down-regulation of Cx40 in Ts65Dn ventricles and were likely contributing to conduction defects. All these data pinpoint new cardiac phenotypes in the Ts65Dn, mimicking aspects of human DS features and pathways altered in the mouse model. In addition they highlight the role of the App-Runx1 interval, including Sod1 and Tiam1, in the induction of post-natal lethality and of the cardiac conduction defects in Ts65Dn. These results might lead to new therapeutic strategies to improve the care of DS people. [ABSTRACT FROM AUTHOR]

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]

Many research works deal with chaotic neural networks for various fields of application. Unfortunately, up to now, these networks are usually claimed to be chaotic without any mathematical proof. The purpose of this paper is to establish, based on a rigorous theoretical framework, an equivalence between chaotic iterations according to Devaney and a particular class of neural networks. On the one hand, we show how to build such a network, on the other hand, we provide a method to check if a neural network is a chaotic one. Finally, the ability of classical feedforward multilayer perceptrons to learn sets of data obtained from a dynamical system is regarded. Various boolean functions are iterated on finite states. Iterations of some of them are proven to be chaotic as it is defined by Devaney. In that context, important differences occur in the training process, establishing with various neural networks that chaotic behaviors are far more difficult to learn. [ABSTRACT FROM AUTHOR]

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]

There is a growing interest in the use of video sensor networks in surveillance applications in order to detect intruders with low cost. The essential concern of such networks is whether or not a specified target can pass or intrude the monitored region without being detected. This concern forms a serious challenge to wireless video sensor networks of weak computation and battery power. In this paper, our aim is to prolong the whole network lifetime while fulfilling the surveillance application needs. We present a novel scheduling algorithm where only a subset of video nodes contributes significantly to detect intruders and prevent malicious attacker to predict the behavior of the network prior to intrusion. Our approach is chaos based, where every node based on its last detection, a hash value and some pseudorandom numbers easily compute a decision function to go to sleep or active mode. We validate the efficiency of our approach through theoretical analysis and demonstrate the benefits of our scheduling algorithm by simulations. Results show that in addition to being able to increase the whole network lifetime and to present comparable results against random attacks (low stealth time), our scheme is also able to withstand malicious attacks due to its fully unpredictable behavior. [ABSTRACT FROM AUTHOR]

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 role of xanthine oxidase (XO) in the defense response of wheat ( Triticum aestivum L.) against the Russian wheat aphid (RWA) ( Diuraphis noxia) was studied. Xanthine oxidase catalyzes the oxidation of hypoxanthine to xanthine to uric acid, and oxygen radicals that are formed as a by-product at both of these oxidation steps may participate in plant defense reactions. A resistant wheat cultivar ( Tugela DN), and a close isogenic susceptible cultivar ( Tugela), were infested with 20-30 aphids per plant before inhibiting xanthine oxidase by adding allopurinol as a soil drench to the resistant plants. Increases in HO content were detected early after infestation in the resistant wheat, and the downstream defense related responses, chitinase and peroxidase activities, were selectively induced by RWA infestation. These downstream defense responses were substantially inhibited in allopurinol treated-resistant wheat, presumably as a response to inhibition of XO, and superoxide dismutase (SOD). We conclude that the production of active oxygen species through the XO system plays an important role in the induction of defense reactions in wheat against the RWA. [ABSTRACT FROM AUTHOR]

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]

We recorded fluctuations in a population of Orange-winged Amazon (Amazona amazonica) during 1 year at a roosting site on an island near Belém, Pará, Brazil. Parrots were counted from a boat by a minimum of three teams of two observers, each team oriented in different directions. Orange-winged Amazons were observed flying alone (14.2%), in pairs (75.7%), and small numbers in family groups (pairs with young) of three (8.7%), four (1.2%), or five (0.3%) individuals. The larger number of groups of three compared with groups of four and five individuals reflects the low survival rate of nestlings with generally only one surviving offspring per brood. The total number of parrots increased from April (3,899) to July (8,539), and began to decrease in August (5,351). This decrease was presumably due to onset of the breeding season, when paired individuals leave the roost in search of a nest, where they breed, nest, and rear young until the nestlings can fly. [ABSTRACT FROM AUTHOR]

Oxysterols from steroid autooxidation have numerous harmful effects, but their biodegradation is poorly understood. Microarrays were used to study mineralization of the most common oxysterol, 7-ketocholesterol (7KC), by Rhodococcusjostii RHA1. Growth on 7KC versus growth on cholesterol resulted in 363 differentially expressed genes, including upregulation of two large gene clusters putatively encoding steroid catabolism. Despite this difference, 7KC degradation required key genes involved in cholesterol degradation, indicating a common catabolic route. [ABSTRACT FROM AUTHOR]

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]

The article describes the use of a parallel algorithm to solve large ordinary differential equation (ODE) systems on distributed clusters. It presents several experiments which compare the parallel variable-coefficient ordinary differential equations (PVODE) solver and parallel algorithm. It relates that parallel algorithm is based on the waveform relaxation concept coupled with a sequential differential equations solver, and is well suited for grid environments connected through high latency network. It indicates that this algorithm reduces the number of messages exchanged between nodes, making it less sensitive to slow communications. Moreover, it reveals the efficiency of algorithm in a grid computing context with high latencies

We develop here a new class of stochastic models of gene evolution in which a random subset of the 64 possible trinucleotides mutates at each evolutionary time t according to some time dependent substitution probabilities. Therefore, at each time t , the numbers and the types of mutable trinucleotides are unknown. Thus, the mutation matrix changes at each time t . This pseudochaotic model developed generalizes the standard model in which all the trinucleotides mutate at each time t . It determines the occurrence probabilities at time t of trinucleotides which pseudochaotically mutate according to 3 time dependent substitution parameters associated with the 3 trinucleotide sites. The main result proves that under suitable assumptions, this pseudochaotic model converges to a uniform probability vector identical to that of the standard model. Furthermore, an application of this pseudochaotic model allows an evolutionary study of the 3 circular codes identified in both eukaryotic and prokaryotic genes. A circular code is a particular set of trinucleotides whose main property is the retrieval of the frames in genes locally, i.e., anywhere in genes and particularly without start codons, and automatically with a window of a few nucleotides. After a certain evolutionary time and with particular time dependent functions for the 3 substitution parameters, precisely an exponential decrease in the 1st and 2nd trinucleotide sites and an exponential increase in the 3rd one, this pseudochaotic model retrieves the main statistical properties of the 3 circular codes observed in genes. Furthermore, it leads to a circular code asymmetry stronger than the standard model (nonpseudochaotic) and, therefore, to a better correlation with the genes. [ABSTRACT FROM AUTHOR]

Based on the Lie-group-algebraic properties of the displacement set and intrinsic coordinate-free geometry, several novel 4-dof overconstrained hybrid parallel manipulators (HPMs) with uncoupled actuation of three spatial translations and one rotation (3T-1R) are proposed. In these HPMs, three limbs are those of Cartesian translational parallel mechanisms (CTPMs) and the fourth limb includes an Oldham-type constant velocity shaft coupling (CVSC). The Lie subgroup of Schoenflies ( X ) displacements of the displacement Lie group and its mechanical generators with nine categories of their general architectures are recalled. A comprehensive enumeration of all possible Oldham-type CVSC limbs is derived from X -motion generators. Their constant velocity (CV) transmissions are verified by group-algebraic approach. Then, combining one CTPM and one CVSC, we synthesize a lot of uncoupled 3T-1R overconstrained HPMs, which are classified into nine distinct classes of general architectures. In addition, all possible architectures with at least one hinged parallelogram or with one cylindrical pair are disclosed too. At last, related non-overconstrained HPMs are attained by the addition of one idle pair in each limb of the previous HPMs. [ABSTRACT FROM AUTHOR]

Catabolic insufficiency in humans leads to the gradual accumulation of a number of pathogenic compounds associated with age-related diseases, including atherosclerosis, Alzheimer's disease, and macular degeneration. Removal of these compounds is a widely researched therapeutic option, but the use of antibodies and endogenous human enzymes has failed to produce effective treatments, and may pose risks to cellular homeostasis. Another alternative is "medical bioremediation," the use of microbial enzymes to augment missing catabolic functions. The microbial genetic diversity in most natural environments provides a resource that can be mined for enzymes capable of degrading just about any energy-rich organic compound. This review discusses targets for biodegradation, the identification of candidate microbial enzymes, and enzyme-delivery methods. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the authors discuss various reports within the issue on topics include atria epicardial mapping in patients with atrial fibrillation (AF), the use of electrogram morphology to determine focal activity from reentry, and high-resolution mapping of AF.

Abstract: We develop here a new class of stochastic models of gene evolution in which the mutations are chaotic, i.e. a random subset of the 64 possible trinucleotides mutates at each evolutionary time t according to some substitution probabilities. Therefore, at each time t, the numbers and the types of mutable trinucleotides are unknown. Thus, the mutation matrix changes at each time t. The chaotic model developed generalizes the standard model in which all the trinucleotides mutate at each time t. It determines the occurrence probabilities at time t of trinucleotides which chaotically mutate according to three substitution parameters associated with the three trinucleotide sites. Two theorems prove that this chaotic model has a probability vector at each time t and that it converges to a uniform probability vector identical to that of the standard model. Furthermore, four applications of this chaotic model (with a uniform random strategy for the 64 trinucleotides and with a particular strategy for the three stop codons) allow an evolutionary study of the three circular codes identified in both eukaryotic and prokaryotic genes. A circular code is a particular set of trinucleotides whose main property is the retrieval of the frames in genes locally, i.e. anywhere in genes and particularly without start codons, and automatically with a window of a few nucleotides. After a certain evolutionary time and with particular values for the three substitution parameters, the chaotic models retrieve the main statistical properties of the three circular codes observed in genes. These applications also allow an evolutionary comparison between the standard and chaotic models. [Copyright &y& Elsevier]

Wireless sensor networks (WSN) constitute a major area of research developing at a very fast pace. Target localisation and coverage are core issues in the field of WSN and represent constraints that affect the effectiveness of WSN. This article focuses on localisation and coverage and identifies a relationship of dependence between the two issues. Throughout this article, a localisation algorithm is proposed and also an energy efficient approach that aims to preserve coverage. The use of a mobile beacon is suggested to divide the region of interest into unit squares following the same method used in the Hilbert space filling curve. A proper choice of the order of the Hilbert curve (i.e. the region subdivisions) is studied to guarantee the localisation of all nodes as well as the total area of coverage. The mobile beacon assists to determine the physical location of undetected nodes by sending beacon packets while traversing the region of interest. It also locally derives an activity scheduling between nodes with a relatively low cost in terms of energy spent by nodes compared to other approaches. In order to validate the effectiveness of the above proposed approach, a series of experiments have been conducted and will be mentioned throughout this article. [ABSTRACT FROM AUTHOR]

Over the last decade, there has been increased attention to the role of earlier HIV testing in the United States. Our objective was to determine if this has translated into changes in the proportion of inpatients with advanced disease at the time of initial HIV diagnosis. We identified inpatients discharged with a new diagnosis of HIV infection or AIDS between 1994 and 2004 at two academic medical centers. We examined trends in initial CD4 count at diagnosis over three time periods: 1994-1996, 1997-2000 and 2001-2004. Between 1994 and 2004, 235 inpatients were newly diagnosed with HIV infection or AIDS in the two centers. For the 217 patients with available CD4 count data, the median initial CD4 count was 41/µl (interquartile range 19-138/µl). Of the 217 patients, 184(85%) had CD4 ≤200/µl and 119/217 (55%) had CD4 ≤50/µl. There were no significant differences in median CD4 count by time period. A large majority of inpatients with newly diagnosed HIV infection at two academic medical centers between 1994 and 2004 had signs of advanced immunodeficiency. Over this recent 11-year period there was no evidence that inpatients with a new HIV diagnosis were identified at earlier stages of disease. [ABSTRACT FROM AUTHOR]

Congenital heart defects (CHD) are common in Down syndrome (DS, trisomy 21). Recently, cardiac sympathetic-parasympathetic imbalance has also been documented in DS adults free of any CHD. The KCNJ6 gene located on human chromosome 21 encodes for the Kir3.2/GIRK2 protein subunits of G protein-regulated K+(KG) channels and could contribute to this altered cardiac regulation. To elucidate the role of its overexpression, we used homozygous transgenic (Tg+/+) mice carrying copies of human KCNJ6. These mice showed human Kir3.2 mRNA expression in the heart and a 2.5-fold increased translation in the atria. Phenotypic alterations were assessed by recording electrocardiogram of urethane anesthetized mice. Chronotropic responses to direct (carbachol) and indirect (methoxamine) muscarinic stimulation were enhanced in Tg+/+mice with respect to wild-type (WT) mice. Alternating periods of slow and fast rhythm induced by CCPA (2-chloro-N-cyclopentyl-adenosine) were amplified in Tg+/+mice, resulting in a reduced negative chronotropic effect. These drugs reduced the atrial P wave amplitude and area. P wave variations induced by methoxamine and CCPA were respectively increased and reduced in the Tg+/+mice, while PR interval and ventricular wave showed no difference between Tg+/+and WT. These results indicate that Tg+/+mice incorporating the human KCNJ6 exhibit altered Kir3.2 expression and responses to drugs that would activate KGchannels. Moreover, these altered expression and responses are limited to sino-atrial node and atria that normally express large amounts of KGchannels. These data suggest that KCNJ6 could play an important role in altered cardiac regulation in DS patients. [ABSTRACT FROM AUTHOR]

Abstract: Osmolytes are small neutral solutes that provide osmotic pressure to the cell without interacting with or denaturing enzymes and cofactors. An increase in the concentration of osmolytes in mammalian renal cells during hyperosmotic stress has been demonstrated to assist in cell volume regulation. More recently uptake of taurine, a common osmolyte, has been reported in tilapia and the carp epithelial cell line, epithelioma papulosum cyprini (EPC), exposed to hyperosmotic stress. The current report investigated whether taurine transporters were present in anadromous salmon and might assist in adaptation to the marine environment. Cloning of the cDNA coding for the taurine transporter in salmon revealed a high degree of identity with the deduced amino acid sequences of taurine transporters from tilapia (93%), carp (90%) and canine (79%). Exposure of isolated tissues to hyperosmotic conditions revealed marked upregulation (2–5 fold) of transcript for the taurine transporter in branchial lamellae, kidney and heart tissue with maximum expression at 125 mM supplemental NaCl and from 24–72 h. Juvenile salmon transferred from freshwater to seawater exhibited a similar elevation in accumulation of taurine transporter mRNA which continued at least 72 h. Supplementation of hyperosmotic tissue culture medium with 5–30 μM taurine failed to reduce cell mortality or alleviate suppression of protein synthesis in branchial lamellae. Oral administration of taurine in the diet of juvenile salmon prior to and during seawater transfer reduced the quantity of taurine transporter mRNA in smolts but not parr. The results indicate that salmon possess a transporter for the osmolyte taurine and suggest it to be one component of an array of mechanisms involved in adaptation to the dehydrating marine environment. [Copyright &y& Elsevier]

Based on the Lie-group-algebraic properties of the displacement set, the three-degree-of-freedom (3DOF) pseudoplanar motion often termed Y motion for brevity is first introduced. Then, all possible general architectures of the mechanical generators of a given Y subgroup are obtained by implementing serial arrays of 1DOF Reuleaux pairs or hinged parallelograms. In total, five distinct mechanical generators of Y motion are revealed and seven ones having at least one parallelogram are also derived from them. In order to avoid the singularity that may occur in the limbs, all singular postures of Y-motion generators are also located by detecting the possible linear dependency of the joint twists and the group dependency of displacement sets. The parallel layout of three 4DOF limbs including Y-motion generators with orthogonal planes make up a Cartesian translational parallel manipulator, which produces a motion set of spatial translations. The 3DOF translation of the moving platform is directly controlled by the three 1DOF translations in three orthogonal prismatic fixed joints. [ABSTRACT FROM AUTHOR]

SUMMARYThe paper introduces a family of three-DOFs translational-rotational Parallel-Kinematics Mechanisms (PKMs) as well as the mobility analysis of such family using Lie-group theory. Each member of this family has two-rotational one-translational DOFs. A novel mechanism is presented and analyzed as a representative of that family. The use and the practical value of that modular mechanism are emphasized. [ABSTRACT FROM AUTHOR]

We examine the energetics of Q-balls in Maxwell–Chern–Simons theory in two space dimensions. Whereas gauged Q-balls are unallowed in this dimension in the absence of a Chern–Simons term due to a divergent electromagnetic energy, the addition of a Chern–Simons term introduces a gauge-field mass and renders finite the otherwise-divergent electromagnetic energy of the Q-ball. Similar to the case of gauged Q-balls , Maxwell–Chern–Simons Q-balls have a maximal charge. The properties of these solitons are studied as a function of the parameters of the model considered, using a numerical technique known as relaxation. The results are compared to expectations based on qualitative arguments. PACS Nos.: 11.10.Lm, 11.10.–z, 11.15.Kc [ABSTRACT FROM AUTHOR]