824 research outputs found

    Compact and explicit physical model for lateral metal-oxide-semiconductor field-effect transistor with nanoelectromechanical system based resonant gate

    Get PDF
    We propose a simple analytical model of a metal-oxide-semiconductor field-effect transistor with a lateral resonant gate based on the coupled electromechanical equations, which are self-consistently solved in time. All charge densities according to the mechanical oscillations are evaluated. The only input parameters are the physical characteristics of the device. No extra mathematical parameters are used to fit the experimental results. Theoretical results are in good agreement with the experimental data in static and dynamic operation. Our model is comprehensive and may be suitable for any electromechanical device based on the field-effect transduction

    Erosion Surface and Granitic Morphology in the Sierra de Lihuel Calel, Province of La Pampa, Argentina

    Get PDF
    Fil: Aguilera, Emilia Yolanda. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Sato, Ana María. Centro de Investigaciones Geológicas (CIG). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Llambías, Eduardo Jorge. Centro de Investigaciones Geológicas (CIG). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Tickyj, Hugo. Departamento de Ciencias Naturales. Facultad de Ciencias Exactas y Naturales. Universidad Nacional de La Pampa; Argentin

    A cross-national study on the antecedents of work–life balance from the fit and balance perspective

    Get PDF
    Drawing on the perceived work–family fit and balance perspective, this study investigates demands and resources as antecedents of work–life balance (WLB) across four countries (New Zealand, France, Italy and Spain), so as to provide empirical cross-national evidence. Using structural equation modelling analysis on a sample of 870 full time employees, we found that work demands, hours worked and family demands were negatively related to WLB, while job autonomy and supervisor support were positively related to WLB. We also found evidence that resources (job autonomy and supervisor support) moderated the relationships between demands and work–life balance, with high resources consistently buffering any detrimental influence of demands on WLB. Furthermore, our study identified additional predictors of WLB that were unique to some national contexts. For example, in France and Italy, overtime hours worked were negatively associated with WLB, while parental status was positively associated with WLB. Overall, the implications for theory and practice are discussed.Peer ReviewedPostprint (author's final draft

    Clarification on protected area management efforts in Madagascar during periods of heightened uncertainty and instability

    Get PDF
    In early May 2022, Eklund and colleagues published an article in Nature Sustainability in which they attempted to demonstrate that the early 2020 lockdown imposed in Madagascar by the emerging COVID-19 pandemic had a direct impact on Protected Areas (PAs), with an increase in the number of fires, which then stabilized once the lockdown was over. The authors, undoubtedly in good faith but based on an incomplete understanding of the situation on the ground, were attempting to draw the attention of the international community and donors to the need to maintain and strengthen PA management efforts. Their contribution, while highlighting a real and urgent need, does not, however, do justice to Madagascar’s PA managers, who, in collaboration with the populations living in the vicinity of parks and reserves, maintained and in some instances increased efforts to ensure the integrity of parks and reserves during the COVID-19 period. Following the publication of this paper, we contacted the authors as well as the editors of Nature Sustainability in a collegial effort to draw their attention to the errors identified in the analysis and to point out how this led to a misinterpretation of what actually transpired during the lockdown. We submitted a carefully worded and argued rebuttal for possible publication in Nature Sustainability, which we regarded as justified given the nature and significance of the considerations we had carefully presented

    A TOMM40 poly-T variant modulates gene expression and is associated with vocabulary ability and decline in nonpathologic aging

    Get PDF
    The Translocase of Outer Mitochondrial Membrane 40 Homolog and Apolipoprotein E (TOMM40-APOE) locus has been associated with a number of age-related phenotypes in humans including nonpathologic cognitive aging, late-onset Alzheimer's disease, and longevity. Here, we investigate the influence of the TOMM40 intron 6 poly-T variant (rs10524523) on TOMM40 gene expression and cognitive abilities and decline in a cohort of 1613 community-dwelling elderly volunteers who had been followed for changes in cognitive functioning over a period of 14 years (range = 12–18 years). We showed that the shorter length poly-T variants were found to act as a repressor of luciferase gene expression in reporter gene constructs. Expression was reduced to approximately half of that observed for the very long variant. We further observed that the shorter poly-T variant was significantly associated with reduced vocabulary ability and a slower rate of vocabulary decline with age compared to the very long poly-T variants. No significant associations were observed for memory, fluid intelligence or processing speed, although the direction of effect, where the short variant was correlated with reduced ability and slower rate of decline was observed for all tests. Our results indicate that the poly-T variant has the ability to interact with transcription machinery and differentially modulate reporter gene expression and influence vocabulary ability and decline with age

    Sedimentation record in the Konkan-Kerala Basin: implications for the evolution of the Western Ghats and the Western Indian passive margin

    Get PDF
    The Konkan and Kerala Basins constitute a major depocentre for sediment from the onshore hinterland of Western India and as such provide a valuable record of the timing and magnitude of Cenozoic denudation along the continental margin. This paper presents an analysis of sedimentation in the Konkan-Kerala Basin, coupledwith a mass balance study, and numerical modelling of flexural responses to onshore denudational unloading and o¡shore sediment loading in order to test competing conceptual models for the development of high-elevation passive margins. The Konkan-Kerala Basin contains an estimated 109,000 km<sup>3</sup>; of Cenozoic clastic sediment, a volume difficult to reconcile with the denudation of a downwarped rift flank onshore, and more consistent with denudation of an elevated rift flank. We infer from modelling of the isostatic response of the lithosphere to sediment loading offshore and denudation onshore that flexure is an important component in the development of the Western Indian Margin.There is evidence for two major pulses in sedimentation: an early phase in the Palaeocene, and a second beginning in the Pliocene. The Palaeocene increase in sedimentation can be interpreted in terms of a denudational response to the rifting between India and the Seychelles, whereas the mechanism responsible for the Pliocene pulse is more enigmatic

    Exploring the performance of the spectrometer prisma in heavy zirconium and xenon mass regions

    Get PDF
    We present results from two recent runs which illustrate the performance of the PRISMA spectrometer in the proximity of the upper limit of its operational interval, namely 96Zr + 124Sn at Elab = 500 MeV and 136Xe + 208Pb at Elab = 930 MeV. In the latter run, the γ array CLARA also allowed us to identify previously unknown γ transitions in the nuclides 136Cs and 134I

    Nano Electro Mechanical Devices for Physical and Chemical Sensing

    Get PDF
    The emergence of MEMS in consumer applications has dramatically increased market perspectives but also puts very strong constraints on cost and integration issues. Addressing these issues through further size reduction is not always relevant as it does not allow maintaining a correct signal to noise ratio (SNR) for the ubiquitous capacitive MEMS sensors. Different solutions are presented here according to the nature of the signal to be sensed: For physical sensors a new concept mixing a micron sized proof mass and a nano-sized detection structure is described. For chemical sensors, the reduction in size actually presents some advantages in terms of high resonant frequency, reduced gas damping, and high sensitivity to applied forces or added mass. Application of nano-resonators to gaz sensing is depicted. Developed originally at the end of the 80's, Micro Electro Mechanical Systems (MEMS) have by now given rise to a mature industry generating this year almost a 10 billion US$ turnover: Silicon micromachining techniques made possible the realisation of ultra-miniature and low cost sensors that allowed the deployment of airbags in cars (MEMS accelerometers are used there to measure the deceleration related to an accident), and more recently, new functions in smart phones. This deployment in large volume applications has triggered interest from large semiconductor industries (STM, TI, Freescale…) and a strong competition towards lower cost and higher integration: The new Grail of the industry is the realization of a 9 Degrees of Freedom sensor, combining the measurement in the 3 directions of space of acceleration, rotation speed and earth magnetic field. As inspired by the semiconductor industry, an obvious answer to these needs is to further decrease the size of the sensors, from Micro to Nano Electro Mechanical Systems (NEMS). However, even taking apart the technological challenges, this is not that simple as physics laws are not always in favour of scaling down: A simple homothetic size reduction does not allow maintaining a correct signal to noise ratio (SNR). As it will be seen here, different types of sensors require different approaches. Nano size detection for physical sensors. As mentioned before, inertial sensors are becoming one of the most ubiquitous sensor today, with applications in industrial, automotive or consumer applications. Further miniaturization is highly sought, as it allows both to decrease the cost (proportional to the surface of silicon) and increase integration (mandatory in portable applications such as smartphones, tablets…). However simple reduction of the seismic mass affects the sensitivity and reduces the nominal capacitance (95% of commercial MEM

    Molecular analysis of HLA-DQB1 alleles in childhood common acute lymphoblastic leukaemia.

    Get PDF
    Epidemiological studies suggest that childhood common acute lymphoblastic leukaemia (c-ALL) may be the rare outcome of early post-natal infection with a common infectious agent. One of the factors that may determine whether a child succumbs to c-ALL is how it responds to the candidate infection. Since immune responses to infection are under the partial control of (human leucocyte antigen) HLA genes, an association between an HLA allele and c-ALL could provide support for an infectious aetiology. To define the limit of c-ALL susceptibility within the HLA region, we have compared HLA-DQB1 allele frequencies in a cohort of 62 children with c-ALL with 76 newborn controls, using group-specific polymerase chain reaction (PCR) amplification, and single-strand conformation polymorphism (SSCP) analysis. We find that a significant excess of children with c-ALL type for DQB1*05 [relative risk (RR): 2.54, uncorrected P=0.038], and a marginal excess with DQB1*0501 (RR: 2.18; P=0.095). Only 3 of the 62 children with c-ALL have the other susceptibility allele, DPB1*0201 as well as DQB1*0501, whereas 15 had one or the other allele. This suggests that HLA-associated susceptibility may be determined independently by at least two loci, and is not due to linkage disequilibrium. The combined relative risk of the two groups of children with DPB1*0201 and/or DQB1*0501 is 2.76 (P=0.0076). Analysis of amino acids encoded by exon 2 of DQB1 reveal additional complexity, with significant (P<0.05) or borderline-significant increases in Gly26, His30, Val57, Glu66-Val67 encoding motifs in c-ALL compared with controls. Since these amino acids are not restricted to DQB1*0501, our results suggest that, as with DPB1, the increased risk of c-ALL associated with DQB1 is determined by specific amino acid encoding motifs rather than by an individual allele. These results also suggest that HLA-associated susceptibility to c-ALL may not be restricted to the region bounded by DPB1 and DQB1
    corecore