Bistability in the Tunnelling Current through a Ring of NN Coupled Quantum Dots

We study bistability in the electron transport through a ring of N coupled quantum dots with two orbitals in each dot. One orbital is localized (called b orbital) and coupling of the b orbitals in any two dots is negligible; the other is delocalized in the plane of the ring (called d orbital), due to coupling of the d orbitals in the neighboring dots, as described by a tight-binding model. The d orbitals thereby form a band with finite width. The b and d orbitals are connected to the source and drain electrodes with a voltage bias V, allowing the electron tunnelling. Tunnelling current is calculated by using a nonequilibrium Green function method recently developed to treat nanostructures with multiple energy levels. We find a bistable effect in the tunnelling current as a function of bias V, when the size N>50; this effect scales with the size N and becomes sizable at N~100. The temperature effect on bistability is also discussed. In comparison, mean-field treatment tends to overestimate the bistable effect.Comment: Published in JPSJ; minor typos correcte

Measurement invariance of the Satisfaction with Life Scale by sexual orientation

The Satisfaction with Life Scale (SWLS) has shown strong evidence of reliability, validity, and gender invariance, and there is some evidence of invariance across age, culture, and educational levels. So far, invariance across sexual orientation has not been studied, despite the number of works that relate well-being to sexual orientation. The SWLS should be invariant across sexual orientation to be able to compare group means. This study aimed to explore the invariance of the SWLS across sexual orientation. A non-probabilistic sample with 553 Spanish adults (208 males, 345 females; 212 heterosexuals, 182 gays, and 138 bisexuals among other sexual orientations) participated in a survey. We tested a one-factor model using confirmatory factor analysis. We tested the configural, metric, and scalar invariance of the factorial structure of the SWLS across sexual orientation with heterosexual, lesbian/gay, and bisexual groups. According to our results, the Spanish version of the SWLS shows scalar invariance across sexual orientations, allowing a valid comparison between sexual minority and heterosexual people. Moreover, in our sample, lesbian/gay and bisexual participants obtained lower scores in life satisfaction than heterosexual participants. Bisexual people obtained the lowest score in well-being compared with the other groups. Implications related to the importance of checking instrument invariance before comparing mean differences between groups are discussed.info:eu-repo/semantics/publishedVersio

A whole-cell biosensor for the detection of gold

Geochemical exploration for gold (Au) is becoming increasingly important to the mining industry. Current processes for Au analyses require sampling materials to be taken from often remote localities. Samples are then transported to a laboratory equipped with suitable analytical facilities, such as Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) or Instrumental Neutron Activation Analysis (INAA). Determining the concentration of Au in samples may take several weeks, leading to long delays in exploration campaigns. Hence, a method for the on-site analysis of Au, such as a biosensor, will greatly benefit the exploration industry. The golTSB genes from Salmonella enterica serovar typhimurium are selectively induced by Au(I/III)-complexes. In the present study, the golTSB operon with a reporter gene, lacZ, was introduced into Escherichia coli. The induction of golTSB::lacZ with Au(I/III)-complexes was tested using a colorimetric β-galactosidase and an electrochemical assay. Measurements of the β-galactosidase activity for concentrations of both Au(I)- and Au(III)-complexes ranging from 0.1 to 5 µM (equivalent to 20 to 1000 ng g⁻¹ or parts-per-billion (ppb)) were accurately quantified. When testing the ability of the biosensor to detect Au(I/III)-complexes(aq) in the presence of other metal ions (Ag(I), Cu(II), Fe(III), Ni(II), Co(II), Zn, As(III), Pb(II), Sb(III) or Bi(III)), cross-reactivity was observed, i.e. the amount of Au measured was either under- or over-estimated. To assess if the biosensor would work with natural samples, soils with different physiochemical properties were spiked with Au-complexes. Subsequently, a selective extraction using 1 M thiosulfate was applied to extract the Au. The results showed that Au could be measured in these extracts with the same accuracy as ICP-MS (P<0.05). This demonstrates that by combining selective extraction with the biosensor system the concentration of Au can be accurately measured, down to a quantification limit of 20 ppb (0.1 µM) and a detection limit of 2 ppb (0.01 µM).Carla M. Zammit, Davide Quaranta, Shane Gibson, Anita J. Zaitouna, Christine Ta, Joël Brugger, Rebecca Y. Lai, Gregor Grass, Frank Reit

Pleosporales

One hundred and five generic types of Pleosporales are described and illustrated. A brief introduction and detailed history with short notes on morphology, molecular phylogeny as well as a general conclusion of each genus are provided. For those genera where the type or a representative specimen is unavailable, a brief note is given. Altogether 174 genera of Pleosporales are treated. Phaeotrichaceae as well as Kriegeriella, Zeuctomorpha and Muroia are excluded from Pleosporales. Based on the multigene phylogenetic analysis, the suborder Massarineae is emended to accommodate five families, viz. Lentitheciaceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae and Trematosphaeriaceae

Activation of peroxydisulfate and peroxymonosulfate by zero-valent iron and FeCu bimetals for 4-chlorophenol oxidation in water

This work systematically evaluates the application of disc-milled iron‐copper (FeCu) bimetals for activating peroxydisulfate (PDS) and peroxymonosulfate (PMS), providing insights into both systems behavior. 4-chlorophenol (4-CP) was chosen as the model pollutant to evaluate the performance of bimetals compared to traditional iron-based activators (Fe2+ and Fe0). The influence of different factors was addressed, including i) bimetals composition (0, 5, and 50 % Cu content), ii) disc-milling, and iii) bimetals concentration. FeCu bimetal with 5 % Cu content showed a better synergy when combined with PMS, resulting in the highest 4-CP degradation, dechlorination, and mineralization (92 %, 62 %, and 60 %, respectively, within 120 min). Different quenchers and PMSO were used to identify the main reactive species in the bimetallic systems, showing the production of Fe4+ with both oxidants and a relevant contribution of 1O2 in the case of PMS. Finally, practical considerations for implementing the FeCu systems have been carefully evaluated, including the potential secondary effects on water quality due to iron and copper release, as well as the stability and reusability of these activators. Adjusting the final pH to 8.0 effectively precipitated dissolved metals, ensuring compliance with Italian environmental quality standards (Fe ≤ 2 mg/L and Cu ≤ 0.1 mg/L). Moreover, Fe5Cu bimetals have shown outstanding stability in repeated uses. Thus, this study introduces a novel, and eco-friendly approach for synthesizing active FeCu bimetals capable of efficiently activating oxidants, offering a promising solution for environmental pollution remediation. While optimal treatment conditions are thoroughly discussed, further studies are needed for full-scale application

Spanish Validation of the Flourishing Scale in the General Population

Well-being research and its measurement have grown in the last two decades. The objective of this study was to adapt and validate the Flourishing Scale in a sample of Spanish adults. This was a cross-sectional study using a non-probabilistic sample of 999 Spanish general adult population participants. The psychometric properties of the scale were analysed from an exploratory and confirmatory perspective. Exploratory factor analysis showed a one-factor solution explaining 42.3% of the variance; an internal consistency of .846; temporal reliability correlation of .749; convergent validity with the Satisfaction with Life Scale of .521 and criterion validity with positive and negative affect (PANAS), pessimism and optimism (LOT-R) ranging from .270 to .488. Confirmatory factor analysis testing the one-factor solution showed a χ2 of 65.57 df = 20; CFI of .982, RMSEA of .06, average variance extracted index of .518 and composite reliability index of .841. Results showed that the Spanish version of the FS is a reliable and valid method for measuring high levels of well-bein

Innate invariant NKT cell recognition of HIV-1-infected dendritic cells is an early detection mechanism targeted by viral immune evasion

Invariant NKT (iNKT) cells are innate-like T cells that respond rapidly with a broad range of effector functions upon recognition of glycolipid Ags presented by CD1d. HIV-1 carries Nef-and Vpu-dependent mechanisms to interfere with CD1d surface expression, indirectly suggesting a role for iNKT cells in control of HIV-1 infection. In this study, we investigated whether iNKT cells can participate in the innate cell-mediated immune response to HIV-1. Infection of dendritic cells (DCs) with Nef-and Vpudeficient HIV-1 induced upregulation of CD1d in a TLR7-dependent manner. Infection of DCs caused modulation of enzymes in the sphingolipid pathway and enhanced expression of the endogenous glucosylceramide Ag. Importantly, iNKT cells responded specifically to rare DCs productively infected with Nef-and Vpu-defective HIV-1. Transmitted founder viral isolates differed in their CD1d downregulation capacity, suggesting that diverse strains may be differentially successful in inhibiting this pathway. Furthermore, both iNKT cells and DCs expressing CD1d and HIV receptors resided in the female genital mucosa, a site where HIV-1 transmission occurs. Taken together, these findings suggest that innate iNKT cell sensing of HIV-1 infection in DCs is an early immune detection mechanism, which is independent of priming and adaptive recognition of viral Ag, and is actively targeted by Nef-and Vpu-dependent viral immune evasion mechanisms

Metacognitive scaffolding boosts cognitive and neural benefits following executive attention training in children

Version of Record online: 25 October 2018Interventions including social scaffolding and metacognitive strategies have been used in educational settings to promote cognition. In addition, increasing evidence shows that computerized process-based training enhances cognitive skills. However, no prior studies have examined the effect of combining these two training strategies. The goal of this study was to test the combined effect of metacognitive scaffolding and computer-based training of executive attention in a sample of typically developing preschoolers at the cognitive and brain levels. Compared to children in the regular training protocol and an untrained active control group, children in the metacognitive group showed larger gains on intelligence and significant increases on an electrophysiological index associated with conflict processing. Moreover, changes in the conflict-related brain activity predicted gains in intelligence in the metacognitive scaffolding group. These results suggest that metacognitive scaffolding boosts the influence of process-based training on cognitive efficiency and brain plasticity related to executive attention.Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: PSI2014-55833-

Clinical Usefulness Of Sars-Cov-2 Rapid Antigen Tests In Adults During High Prevalence Community Outbreaks

We evaluated performance of Abbott PanBio® COVID-19 Rapid Antigen Test Device (RATD) to detect SARS-CoV-2 infection in adults during high prevalence COVID-19 outbreaks. We found high accuracy in correct diagnosis (88% CI 85-91%, p<0.05) regardless of gender, presence of symptoms, disease timeline. Test sensitivity appeared to increase with age, specificity seemed to decline. Best diagnostic accuracy was obtained in middle-aged adults (94% CI 89-97%, p<0.05), but remained high through all ages. These results support RATD as a reliable measure to determine isolation of infected individuals during outbreaks. More studies are needed to assess RATD performance in low prevalence post-vaccination scenarios.http://deepblue.lib.umich.edu/bitstream/2027.42/166596/1/AFM-177-21_PP.pdfDescription of AFM-177-21_PP.pdf : Main ArticleSEL

Implication of mitochondria-derived ROS and cardiolipin peroxidation in N-(4-hydroxyphenyl)retinamide-induced apoptosis

We have studied the effect of N-(4-hydroxyphenyl)retinamide on either malignant human leukaemia cells or normal cells and investigated its mechanism of action. We demonstrate that 4HPR induces reactive oxygen species increase on mitochondria at a target between mitochondrial respiratory chain complex I and II. Such oxidative stress causes cardiolipin peroxidation which in turn allows cytochrome c release to cytosol, caspase-3 activation and therefore apoptotic consumption. Moreover, this apoptotic pathway seems to be bcl-2/bax independent and count only on malignant cells but not normal nor activated lymphocytes