The manifest association structure of the single-factor model: insights from partial correlations

The association structure between manifest variables arising from the single-factor model is investigated using partial correlations. The additional insights to the practitioner provided by partial correlations for detecting a single-factor model are discussed. The parameter space for the partial correlations is presented, as are the patterns of signs in a matrix containing the partial correlations that are not compatible with a single-factor model

Microscopic theory for quantum mirages in quantum corrals

Scanning tunneling microscopy permits to image the Kondo resonance of a single magnetic atom adsorbed on a metallic surface. When the magnetic impurity is placed at the focus of an elliptical quantum corral, a Kondo resonance has been recently observed both on top of the impurity and on top of the focus where no magnetic impurity is present. This projection of the Kondo resonance to a remote point on the surface is referred to as quantum mirage. We present a quantum mechanical theory for the quantum mirage inside an ideal quantum corral and predict that the mirage will occur in corrals with shapes other than elliptical

Influence of CaCl2.2H2O Content on the Productive Process of Composites from Cotton Gin Waste

AbstractPrevious studies have shown the feasibility of production of masonry blocks and panels from agglomeration of cotton gin waste and calcium binders. Cotton gin waste is a serious problem for ginning plants, because in Argentina approximately 300,000 t of lignocellulosic wastes are produced annually without any final disposal destination. The accumulation of these residues is associated with pests and fire hazards. Since these composites are produced with simple equipment and a minimum energy requirement, their cost depends mainly on the binder (Portland cement) used and the process efficiency, since with a high productivity model, labor and equipment depreciation costs are significantly reduced. This paper analyzes the influence of CaCl2.2H2O (added as an accelerator for cement paste strength) on the minimum molding time required for composites manufacturing. A central composite experimental design was developed in order to study the interrelated variables. The influence of CaCl2.2H2O content on physical-mechanical cement paste properties and their relationship with composites stability are also evaluated. The results of this work show that CaCl2.2H2O content has significant influence on the efficiency of composites manufacturing as it reduces the molding time required

Antimicrobial activity of a continuous visible light disinfection system

We evaluated the ability of high-intensity visible violet light with a peak output of 405 nm to kill epidemiologically important pathogens. The high irradiant light significantly reduced both vegetative bacteria and spores at some time points over a 72-hour exposure period

Drivers of long-term variability in CO2 net ecosystem exchange in a temperate peatland

Land–atmosphere exchange of carbon dioxide (CO2) in peatlands exhibits marked seasonal and inter-annual variability, which subsequently affects the carbon (C) sink strength of catchments across multiple temporal scales. Long-term studies are needed to fully capture the natural variability and therefore identify the key hydrometeorological drivers in the net ecosystem exchange (NEE) of CO2. Since 2002, NEE has been measured continuously by eddy-covariance at Auchencorth Moss, a temperate lowland peatland in central Scotland. Hence this is one of the longest peatland NEE studies to date. For 11 years, the site was a consistent, yet variable, atmospheric CO2 sink ranging from −5.2 to −135.9 g CO2-C m−2 yr−1 (mean of −64.1 ± 33.6 g CO2-C m−2 yr−1). Inter-annual variability in NEE was positively correlated to the length of the growing season. Mean winter air temperature explained 87% of the inter-annual variability in the sink strength of the following summer, indicating an effect of winter climate on local phenology. Ecosystem respiration (Reco) was enhanced by drought, which also depressed gross primary productivity (GPP). The CO2 uptake rate during the growing season was comparable to three other sites with long-term NEE records; however, the emission rate during the dormant season was significantly higher. To summarise, the NEE of the peatland studied is modulated by two dominant factors: - phenology of the plant community, which is driven by winter air temperature and impacts photosynthetic potential and net CO2 uptake during the growing season (colder winters are linked to lower summer NEE), - water table level, which enhanced soil respiration and decreased GPP during dry spells. Although summer dry spells were sporadic during the study period, the positive effects of the current climatic trend towards milder winters on the site's CO2 sink strength could be offset by changes in precipitation patterns especially during the growing season

Effects of total and regional fat loss on plasma CRP and IL-6 in overweight and obese, older adults with knee osteoarthritis

SummaryObjectiveTo describe associations between total and regional body fat mass loss and reduction of systemic levels of inflammation (C-reactive protein (CRP) and interleukin-6 (IL-6)) in obese, older adults with osteoarthritis (OA), undergoing intentional weight loss.DesignData come from a single-blind, 18-month, randomized controlled trial in adults (age: 65.6 ± 6.2; Body mass index (BMI): 33.6 ± 3.7) with knee OA. Participants were randomized to diet-induced weight loss plus exercise (D + E; n = 150), diet-induced weight loss-only (D; n = 149), or exercise-only (E; n = 151). Total body and region-specific (abdomen and thigh) fat mass were measured at baseline and 18 months. High-sensitivity CRP and IL-6 were measured at baseline, six and 18 months. Intervention effects were assessed using mixed models and associations between inflammation and adiposity were compared using logistic and mixed linear regression models.ResultsIntentional total body fat mass reduction was associated with significant reductions in log-adjusted CRP (β = 0.06 (95% CI = 0.04, 0.08) mg/L) and IL-6 (β = 0.02 (95% CI = 0.01, 0.04) pg/mL). Loss of abdominal fat volume was also associated with reduced inflammation, independent of total body fat mass; although models containing measures of total adiposity yielded the best fit. The odds of achieving clinically desirable levels of CRP (<3.0 mg/L) and IL-6 (<2.5 pg/mL) were 3.8 (95% CI = 1.6, 8.9) and 2.2 (95% CI = 1.1, 4.6), respectively, with 5% total weight and fat mass loss.ConclusionsAchievement of clinically desirable levels of CRP and IL-6 more than double with intentional 5% loss of total body weight and fat mass. Global, rather than regional, measures of adiposity are better predictors of change in inflammatory burden.Clinical Trial Registration NumberNCT00381290

Carrier induced ferromagnetism in diluted magnetic semi-conductors

We present a theory for carrier induced ferromagnetism in diluted magnetic semi-conductor (DMS). Our approach treats on equal footing quantum fluctuations within the RPA approximation and disorder within CPA. This method allows for the calculation of $T_c$, magnetization and magnon spectrum as a function of hole, impurity concentration and temperature. It is shown that, sufficiently close to $T_c$, and within our decoupling scheme (Tyablicov type) the CPA for the itinerant electron gas reduces to the Virtual Crystal Approximation. This allows, in the low impurity concentration and low density of carriers to provide analytical expression for $T_c$. For illustration, we consider the case of $Ga_{1-c}Mn_{c}As$ and compare our results with available experimental data.Comment: 5 figures included. to appear in Phys. Rev. B (brief report

Single and double qubit gates by manipulating degeneracy

A novel mechanism is proposed for single and double qubit state manipulations in quantum computation with four-fold degenerate energy levels. The principle is based on starting with a four fold degeneracy, lifting it stepwise adiabatically by a set of control parameters and performing the quantum gate operations on non-degenerate states. A particular realization of the proposed mechanism is suggested by using inductively coupled rf-squid loops in the macroscopic quantum tunnelling regime where the energy eigen levels are directly connected with the measurable flux states. The one qubit and two qubit controlled operations are demonstrated explicitly. The appearance of the flux states also allows precise read-in and read-out operations by the measurement of flux.Comment: 6 pages + 5 figures (separately included

The Topological B-model on a Mini-Supertwistor Space and Supersymmetric Bogomolny Monopole Equations

In the recent paper hep-th/0502076, it was argued that the open topological B-model whose target space is a complex (2|4)-dimensional mini-supertwistor space with D3- and D1-branes added corresponds to a super Yang-Mills theory in three dimensions. Without the D1-branes, this topological B-model is equivalent to a dimensionally reduced holomorphic Chern-Simons theory. Identifying the latter with a holomorphic BF-type theory, we describe a twistor correspondence between this theory and a supersymmetric Bogomolny model on R^3. The connecting link in this correspondence is a partially holomorphic Chern-Simons theory on a Cauchy-Riemann supermanifold which is a real one-dimensional fibration over the mini-supertwistor space. Along the way of proving this twistor correspondence, we review the necessary basic geometric notions and construct action functionals for the involved theories. Furthermore, we discuss the geometric aspect of a recently proposed deformation of the mini-supertwistor space, which gives rise to mass terms in the supersymmetric Bogomolny equations. Eventually, we present solution generating techniques based on the developed twistorial description together with some examples and comment briefly on a twistor correspondence for super Yang-Mills theory in three dimensions.Comment: 55 pages; v2: typos fixed, published versio

Antimicrobial activity of a continuously active disinfectant against healthcare pathogens

A novel disinfectant studied using an EPA protocol demonstrated sustained antimicrobial activity (ie, 3-5 log10 reduction) in 5 minutes after 24 hours for Staphylococcus aureus, vancomycin-resistant Enterococcus, Candida auris, carbapenem-resistant Escherichia coli and antibiotic-susceptible E. coli, and Enterobacter spp. Only ∼2 log10 reduction occurred with carbapenem-resistant Enterobacter spp and K. pneumoniae, and antibiotic-susceptible K. pneumoniae