AMPK Phosphorylation Is Controlled by Glucose Transport Rate in a PKA-Independent Manner

To achieve growth, microbial organisms must cope with stresses and adapt to the environment, exploiting the available nutrients with the highest efficiency. In Saccharomyces cerevisiae, Ras/PKA and Snf1/AMPK pathways regulate cellular metabolism according to the supply of glucose, alternatively supporting fermentation or mitochondrial respiration. Many reports have highlighted crosstalk between these two pathways, even without providing a comprehensive mechanism of regulation. Here, we show that glucose-dependent inactivation of Snf1/AMPK is independent from the Ras/PKA pathway. Decoupling glucose uptake rate from glucose concentration, we highlight a strong coordination between glycolytic metabolism and Snf1/AMPK, with an inverse correlation between Snf1/AMPK phosphorylation state and glucose uptake rate, regardless of glucose concentration in the medium. Despite fructose-1,6-bisphosphate (F1,6BP) being proposed as a glycolytic flux sensor, we demonstrate that glucose-6-phosphate (G6P), and not F1,6BP, is involved in the control of Snf1/AMPK phosphorylation state. Altogether, this study supports a model by which Snf1/AMPK senses glucose flux independently from PKA activity, and thanks to conversion of glucose into G6P.     

Endometrial cytology during menstrual cycle, menopause and progestinic treatment

The AA. examined 72 cytological smears of the human normal endometrium. Twenty-three were taken during the proliferative phase, 17 during the secretory phase, 21 during menopause and 11 during estro-progestinic treatment. The study pointed out that the endometrial smear, which has been employed up to now almost exclusively in the cyto-oncological field, is also quite suitable for a dynamic cyto-functional evaluation of ovarian function, because of the series of interpretative elements, easily and readily identifiable at the microscope, which it furnishes.     

Numerical Analysis of Convective Instabilities in a Transient Short-Hot-Wire Setup for Measurement of Liquid Thermal Conductivity

Numerical simulation has been used to investigate the effects of natural convection on measurements of the thermal conductivity of fluids by transient hot-wire methods. Comparison of the numerical data with the experimental results obtained with a custom-built setup exploiting a short-wire geometry allows fixing an operationally useful time scale, where convective effects can be safely neglected.     

Nanoparticle deposition effects on the minimum heat flux point and quench front speed during quenching in water-based alumina nanofluids

The quenching characteristics of metallic rodlets and spheres were investigated in pure water and water-based nanofluids with alumina nanoparticles of 0.1% by volume. The experiments were performed at both saturated and subcooled conditions under atmospheric pressure. The results demonstrate that while the initial quenching behavior in nanofluids is identical to that in pure water, both the minimum heat flux point temperature and quench front speed are significantly enhanced in subsequent quenching repetitions due to nanoparticle deposition. The nanoparticle effects on the quenching process were analyzed with focus on the intermittent liquid–solid contacts in the film boiling regime. It appears that the liquid–solid interaction during such short-lived contacts is more vigorous when a nanoparticle layer with improved surface wettability and roughness is present, which leads to the premature disruption of film boiling and quenching acceleration.     

Energy consumption feedback in perspective: integrating Australian data to meta-analyses on in-home displays

Providing homeowners with real-time feedback on their electricity consumption through a dedicated display device has been shown to reduce consumption by approximately 6–10 %. However, recent advances in smart grid technology have enabled larger sample sizes and more representative sample selection and recruitment methods for display trials. By analyzing these factors using data from current studies, this paper argues that a realistic, large-scale conservation effect from feedback is in the range of 3–5 %. Subsequent analysis shows that providing real-time feedback may not be a cost effective strategy for reducing carbon emissions in Australia, but that it may enable additional benefits such as customer retention and peak-load shift.     

Functionalized Fe‐Filled Multiwalled Carbon Nanotubes as Multifunctional Scaffolds for Magnetization of Cancer Cells

With the aim to design addressable magnetically‐active carbon nanotubes (CNTs) for cancer treatment, the use of Fe‐filled CNTs (Fe@MWCNTs) as multifunctional scaffolds is reported for exohedrally anchoring a monoclonal antibody (mAb) known to bind a plasma membrane receptor over‐expressed in several cancer cells (EGFR). Comprehensive microscopic (transmission electron microscopy, atomic force microscopy, and scanning electron microscopy) and spectroscopic (Raman, ⁵⁷Fe Mossbauer, energy dispersive spectroscopy, X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction) characterizations reveal the efficient confinement of magnetically‐active Fe phases (α‐Fe and Fe₃C), while compositional evaluations through XPS, thermogravimetric analysis and gel electrophoresis confirm that mAb immobilization onto Fe@MWCNTs occurs. Enzyme‐linked immunosorbent assay (ELISA), confocal microscopy imaging and western blotting confirm the targeting action toward EGFR‐overexpressing cell lines (EGFR+). In vitro magnetic filtration experiments demonstrate that a selective removal of EGFR+ cells from a mixed population of healthy cell lines could be obtained in very short times (≈10 min). Cytotoxicity evaluations by classic cell staining procedures after application of an electromagnetic radiation inducing magnetic fluid hyperthermia (MFH), show a selective suppression of the EGFR+ cell line. Molecular dynamics and docking simulations of the hybrid mAb/Fe@MWCNTs conjugates nicely show how the presence of the CNT framework does not sterically affect the conformational properties of the two antigen binding regions, further supporting the biochemical findings.     

Two‐Color Emitting Colloidal Nanocrystals as Single‐Particle Ratiometric Probes of Intracellular pH

Intracellular pH is a key parameter in many biological mechanisms and cell metabolism and is used to detect and monitor cancer formation and brain or heart diseases. pH‐sensing is typically performed by fluorescence microscopy using pH‐responsive dyes. Accuracy is limited by the need for quantifying the absolute emission intensity in living biological samples. An alternative with a higher sensitivity and precision uses probes with a ratiometric response arising from the different pH‐sensitivity of two emission channels of a single emitter. Current ratiometric probes are complex constructs suffering from instability and cross‐readout due to their broad emission spectra. Here, we overcome such limitations using a single‐particle ratiometric pH probe based on dot‐in‐bulk CdSe/CdS nanocrystals (NCs). These nanostructures feature two fully‐separated narrow emissions with different pH sensitivity arising from radiative recombination of core‐ and shell‐localized excitons. The core emission is nearly independent of the pH, whereas the shell luminescence increases in the 3–11 pH range, resulting in a cross‐readout‐free ratiometric response as strong as 600%. In vitro microscopy demonstrates that the ratiometric response in biologic media resembles the precalibralation curve obtained through far‐field titration experiments. The NCs show good biocompatibility, enabling us to monitor in real‐time the pH in living cells.     

Exact Solution for Transverse Electric Polarized Nonlinear Guided Waves in Saturable Media

Abstract

The power dependent wave-vector and stationary field distributions for TE polarized nonlinear waves guided by an interface between a linear dielectric and a saturable nonlinear self-focusing medium characterized by the dielectric function ? = ?_c + α_c¦E¦² + β_c¦E¦⁴ are exactly calculated. Exact nonlinear wave solutions are also given for TE polarized nonlinear waves guided by dielectric or metallic films bounded on one side by a self-focusing saturable medium characterized by the above dielectric function. The stability on propagation of these nonlinear stationary wave solutions was investigated numerically.