Quantum-SAR Extension of the Spectral-SAR Algorithm. Application to Polyphenolic Anticancer Bioactivity

Aiming to assess the role of individual molecular structures in the molecular mechanism of ligand-receptor interaction correlation analysis, the recent Spectral-SAR approach is employed to introduce the Quantum-SAR (QuaSAR) “wave” and “conversion factor” in terms of difference between inter-endpoint inter-molecular activities for a given set of compounds; this may account for inter-conversion (metabolization) of molecular (concentration) effects while indicating the structural (quantum) based influential/detrimental role on bio-/eco- effect in a causal manner rather than by simple inspection of measured values; the introduced QuaSAR method is then illustrated for a study of the activity of a series of flavonoids on breast cancer resistance protein

On Heisenberg Uncertainty Relationship, Its Extension, and the Quantum Issue of Wave-Particle Duality

Within the path integral Feynman formulation of quantum mechanics, the fundamental Heisenberg Uncertainty Relationship (HUR) is analyzed in terms of the quantum fluctuation influence on coordinate and momentum estimations. While introducing specific particle and wave representations, as well as their ratio, in quantifying the wave-to-particle quantum information, the basic HUR is recovered in a close analytical manner for a large range of observable particle-wave Copenhagen duality, although with the dominant wave manifestation, while registering its progressive modification with the factor 1-n2, in terms of magnitude n∈[0,1]. of the quantum fluctuation, for the free quantum evolution around the exact wave-particle equivalence. The practical implications of the present particle-to-wave ratio as well as of the free-evolution quantum picture are discussed for experimental implementation, broken symmetry and the electronic localization function

Assessment of the Impacts of ACLS on the ISS Life Support System Using Dynamic Simulations in V-HAB

The Advanced Closed Loop System (ACLS) is currently under development by Airbus Defense and Space and is slated for launch to the International Space Station (ISS) in 2017. The addition of new hardware into an already complex system such as the ISS life support system (LSS) always poses operational risks. It is therefore important to understand the impacts ACLS will have on the existing systems to ensure smooth operations for the ISS. This analysis can be done by using dynamic computer simulations and one possible tool for such a simulation is the Virtual Habitat (V-HAB). Based on MATLAB, V-HAB has been under development at the Institute of Astronautics of the Technical University of Munich (TUM) since 2004 and in the past has been successfully used to simulate the ISS life support systems. The existing V-HAB ISS simulation model treated the interior volume of the space station as one large, ideally-stirred container. This model was improved to allow the calculation of the atmospheric composition inside individual modules of the ISS by splitting it into twelve distinct volumes. The virtual volumes are connected by a simulation of the inter-module ventilation flows. This allows for a combined simulation of the LSS hardware and the atmospheric composition aboard the ISS. A dynamic model of ACLS is added to the ISS Simulation and several different operating modes for both ACLS and the existing ISS life support systems are studied and the impacts of ACLS on the rest of the system are determined. The results suggest that the US, Russian and ACLS CO2 systems can operate at the same time without impeding each other. Furthermore, based on the results of this analysis, the US and ACLS Sabatier systems can be operated in parallel as well to a achieve a very low CO2 concentration in the cabin atmosphere

Bedrock erosion by root fracture and tree throw: A coupled biogeomorphic model to explore the humped soil production function and the persistence of hillslope soils

In 1877, G. K. Gilbert reasoned that bedrock erosion is maximized under an intermediate soil thickness and declines as soils become thinner or thicker. Subsequent analyses of this “humped” functional relationship proposed that thin soils are unstable and that perturbations in soil thickness would lead to runaway thinning or thickening of the soil. To explore this issue, we developed a numerical model that simulates the physical weathering of bedrock by root fracture and tree throw. The coupled biogeomorphic model combines data on conifer population dynamics, rootwad volumes, tree throw frequency, and soil creep from the Pacific Northwest (USA). Although not hardwired into the model, a humped relationship emerges between bedrock erosion and soil thickness. The magnitudes of the predicted bedrock erosion rates and their functional dependency on soil thickness are consistent with independent field measurements from a coniferous landscape in the region. Imposed perturbations of soil erosion during model runs demonstrate that where bedrock weathering is episodic and localized, hillslope soils do not exhibit runaway thinning or thickening. The pit-and-mound topography created by tree throw produces an uneven distribution of soil thicknesses across a hillslope; thus, although episodes of increased erosion can lead to temporary soil thinning and even the exposure of bedrock patches, local areas of thick soils remain. These soil patches provide habitat for trees and serve as nucleation points for renewed bedrock erosion and soil production. Model results also suggest that where tree throw is a dominant weathering process, the initial mantling of bedrock is not only a vertical process but also a lateral process: soil mounds created by tree throw flatten over time, spreading soil over bedrock surfaces

The Effects of Restoring Logged Tropical Forests on Avian Phylogenetic and Functional Diversity.

Selective logging is the most prevalent land-use change in the tropics. Despite the resulting degradation of forest structure, selectively logged forests still harbour a substantial amount of biodiversity leading to suggestions that their protection is the next best alternative to conserving primary, old-growth forests. Restoring carbon stocks under Reducing Emissions from Deforestation and Forest Degradation (REDD+) schemes is a potential method for obtaining funding to protect logged forests, via enrichment planting and liberation cutting of vines. This study investigates the impacts of restoring logged forests in Borneo on avian phylogenetic diversity-the total evolutionary history shared across all species within a community-and on functional diversity, with important implications for the protection of evolutionarily unique species and the provision of many ecosystem services. Overall and understorey avifaunal communities were studied using point count and mist-netting surveys, respectively. Restoration caused a significant loss in phylogenetic diversity and MPD (mean pairwise distance) leaving an overall bird community of less total evolutionary history and more closely related species compared to unlogged forests, while the understorey bird community had MNTD (mean nearest taxon distance) that returned towards the lower levels found in a primary forest, indicating more closely related species pairs. The overall bird community experienced a significant loss of functional strategies and species with more specialized traits in restored forests compared to that of unlogged forests, which led to functional clustering in the community. Restoration also led to a reduction in functional richness and thus niches occupied in the understorey bird community compared to unlogged forests. While there are additional benefits of restoration for forest regeneration, carbon sequestration, future timber harvests, and potentially reduced threat of forest conversion, this must be weighed against the apparent loss of phylogenetic and functional diversity from unlogged forest levels, making the biodiversity-friendliness of carbon sequestration schemes questionable under future REDD+ agreements. To reduce perverse biodiversity outcomes, it is important to focus restoration only on the most degraded areas or at reduced intensity where breaks between regimes are incorporated. This article is protected by copyright. All rights reserved

Composite quasiparticle formation and the low-energy effective Hamiltonians of the one- and two-dimensional Hubbard Model

We investigate the effect of hole doping on the strong-coupling Hubbard model at half-filling in spatial dimensions $D\ge 1$. We start with an antiferromagnetic mean-field description of the insulating state, and show that doping creates solitons in the antiferromagnetic background. In one dimension, the soliton is topological, spinless, and decoupled from the background antiferromagnetic fluctuations at low energies. In two dimensions and above, the soliton is non-topological, has spin quantum number 1/2, and is strongly coupled to the antiferromagnetic fluctuations. We derive the effective action governing the quasiparticle motion, study the properties of a single carrier, and comment on a possible description at finite concentration.Comment: REVTEX 3.0, 22 pages with 14 figures in the PostScript format compressed using uufile. Submitted to Phys. Rev. B. The complete PostScript file including figures can be obtained via ftp at ftp://serval.berkeley.edu/hubbard.ps . It is also available via www at http://roemer.fys.ku.dk/recent.ht

Estimating upper limb discomfort level due to intermittent isometric pronation torque with various combinations of elbow angles, forearm rotation angles, force and frequency with upper arm at 90 degrees abduction

peer-reviewedIndustrial jobs involving upper arm abduction have a strong association with musculoskeletal disorders and injury. But there is still paucity of data on the different risk factors that are responsible for the genesis of such disorders or injuries. The current laboratory study is an attempt in that direction. Thirty-six right-handed male university students participated in a full factorial model of three forearm rotation angles (60% prone and supine and neutral range of motion), three elbow angles (45 degrees, 90 degrees and 135 degrees), two exertion frequencies (10 and 20/min) and two levels of pronation torque (10% and 20% MVC). Discomfort rating after each five-minute treatment was recorded on a visual analogue scale. Repeated measures ANCOVA with grip endurance time as a covariate indicated that forearm rotation angle (p = 0.001), elbow flexion angle (p = 0.016), MVC torque (p = 0.001) and frequency (p = 0.049) were significant. Grip endurance time was not significant (p = 0.74). EMG activity of the Pronator Teres (PT) and the Extensor Carpi Radialis Brevis (ECRB) revealed that both muscles were affected by forearm rotation and level of MVC torque. A supplementary experiment in which MVC pronation torque at different articulations was measured showed that some of the increased discomfort appeared to be due to increased relative NIVC at some of the extreme articulations. The findings indicated that, with the upper arm in abduction, an elbow angle of 45 degrees and forearm prone, are a posture vulnerable to injury and should be avoided. Grip endurance time as a covariate warrants further investigation. Relevance to industry There is still a paucity of data on risk factors for musculoskeletal disorders for upper arm articulations typical of industrial jobs, especially postures involving upper arm abduction. Industrial jobs involving upper arm abduction have a strong association with injury as operators must often maintain static upper arm abduction while performing tasks for long durations. This study presents discomfort and pronation torque MVC data at different upper arm articulations to identify and control high-risk tasks in industry well before they develop into Musculoskeletal Disorders, especially at the design stage when using biomechanical models. (c) 2007 Elsevier B.V. All rights reserved.ACCEPTEDpeer-reviewe

Isolation and characterization of saprophytic and pathogenic strains of Leptospira from water sources in the Midwestern United States

The genus Leptospira is a diverse and unique group of bacteria comprising multiple saprophytic and pathogenic species, which survive and persist in suitable moist environments. Pathogenic species cause human and animal leptospirosis, a global and neglected zoonotic disease. Disease transmission occurs by exposure to contaminated water and moist soil environments or by contact with domestic animals and wildlife acting as reservoir hosts that shed Leptospira via urine. Here, we describe the unexpected diversity of saprophytic and pathogenic species of Leptospira isolated from water in the Midwestern United States. Samples were collected by volunteers in 11 counties in Iowa from water sources, including puddles, sewage, creeks, ponds, lakes, and rivers, during the summer of 2021. One hundred and five water samples were tested by culture for the presence of saprophytic and pathogenic species and by lipL32 qPCR specific for the detection of pathogens; 82 (78.1%) were culture positive and five (4.8%) were positive by lipL32 qPCR. Whole genome sequencing of isolates cultured from water samples identified 10 species of saprophytes, namely L. montravelensis, L. kemamanensis, L. bandrabouensis, L. bourretii, L. bouyouniensis, L. chreensis, L. ellinghausenii, L. terpstrae, L. yanagawae, and L. abararensis, as well as three novel saprophytic species. Whole genome sequencing also identified two novel pathogenic species. The remaining cultures comprised mixed populations of saprophytic species and six comprised a mixture of saprophytic and pathogenic species. One of these mixed cultures was enriched to select for a clonal isolate of pathogenic Leptospira, strain WS101.C1, which was classified as L. interrogans serogroup Djasiman serovar Djasiman. Cumulatively, 9.5% (10/105) of water samples were positive for pathogenic Leptospira. This study emphasizes the diversity of Leptospira present in water sources in the Midwestern United States and provides unique opportunities to explore the geographic diversity and evolution of this genus. The identification of known and novel pathogenic species circulating in local water sources highlights their potential usefulness as diagnostic antigens, as well as the role of water in the transmission of infection to human and animal populations. Integrating knowledge on human, animal, and environmental health is essential to control and predict risk for zoonoses

Adult digit ratio (2D:4D) is not related to umbilical cord androgen or estrogen concentrations, their ratios or net bioactivity

Background: Ratio of second digit length to fourth digit length (2D:4D) has been extensively used in human and experimental research as a marker of fetal sex steroid exposure. However, very few human studies have measured the direct relationship between fetal androgen or estrogen concentrations and digit ratio. Aims: We investigated the relationships between both androgen and estrogen concentrations in umbilical cord blood and digit ratio in young adulthood. In addition we calculated measures of total serum androgen and total estrogen bioactivity and investigated their relationship to digit ratio. Study design: Prospective cohort study. Subjects: An unselected subset of the Western Australian Pregnancy Cohort (Raine) Study (159 female; 182 male). Outcome measures: Cord serum samples were collected immediately after delivery. Samples were assayed for androgen (testosterone, Δ4-androstenedione, dehydroepiandrosterone) and estrogen (estrone, estradiol, estriol, estetrol) concentrations using liquid-chromatography mass-spectrometry. Digit ratio measurements were taken from hand photocopies at age 19–22 years. Results: For both males and females, there were no significant correlations between digit ratio and any androgen or estrogen concentrations considered individually, the testosterone to estradiol ratio, total androgen bioactivity measure or ratio of androgen to estrogen bioactivity (all p > .05). In males, but not females, total estrogen bioactivity was negatively correlated with left hand digit ratio (r = − .172, p = .02), but this relationship was no longer significant when adjusted for variables known to affect sex steroid concentrations in cord blood. Conclusions: Our findings indicate that digit ratio is not related to fetal androgens or estrogens at late gestation

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte