Spectral Analysis of Discrete Metastable Diffusions

We consider a discrete Schrödinger operator Hε = −ε2ε + Vε on 2(εZd ), where ε > 0 is a small parameter and the potential Vε is defined in terms of a multiwell energy landscape f on Rd . This operator can be seen as a discrete analog of the semiclassical Witten Laplacian of Rd . It is unitarily equivalent to the generator of a diffusion on εZd , satisfying the detailed balance condition with respect to the Boltzmann weight exp (− f/ε). These type of diffusions exhibit metastable behavior and arise in the context of disordered mean field models in Statistical Mechanics. We analyze the bottom of the spectrum of Hε in the semiclassical regime ε 1 and show that there is a one-to-one correspondence between exponentially small eigenvalues and local minima of f . Then we analyze in more detail the bistable case and compute the precise asymptotic splitting between the two exponentially small eigenvalues. Through this purely spectral-theoretical analysis of the discrete Witten Laplacian we recover in a self-contained way the Eyring–Kramers formula for the metastable tunneling time of the underlying stochastic process

Beyond Income and Inequlity: The Role of Socio-Political Factors for Alleviating Energy Poverty in Europe

In each country, the occurrence of energy poverty among resident households is usually related to low income and its unequal distribution. Like other manifestations of material deprivation, however, such a phenomenon is likely to be also correlated with some internal socio-political factors that allow its persistence by preventing effective solutions. In this paper, we build and analyse a dataset for European countries by assessing the role of the perceived quality of internal public governance on different measures of energy deprivation. Specifically, we rely on the Worldwide Governance Indicators provided by the World Bank and estimate an array of panel models. After controlling for income, income inequality, energy prices, and weather conditions, we find that high government effectiveness, good regulatory quality, widespread property rights, contract enforcement, and corruption control are significantly associated with lower energy poverty. In addition, we consider the policy implications of this broader perspective on energy deprivation

Cardiovascular Responses to Simultaneous Diving and Muscle Metaboreflex Activation

Background: The aim of study was to assess hemodynamic changes during the simultaneous activation of muscle metaboreflex (MM) and diving reflex (DR) in a laboratory setting. We hypothesized that as long as the exercise intensity is mild DR can overwhelm the MM. Methods: Ten trained divers underwent all four phases (randomly assigned) of the following protocol. (A) Postexercise muscle ischemia session (PEMI): 3 min of resting followed by 3 min of handgrip at 30% of maximum force, followed immediately by 3 min of PEMI on the same arm induced by inflating a sphygmomanometer. Three minutes of recovery was further allowed after the cuff was deflated for a total of 6 min of recovery. (B) Control exercise recovery session: the same rest-exercise protocol used for A followed by 6 min of recovery without inflation. (C) DR session: the same rest-exercise protocol used for A followed by 1 min of breath-hold (BH) with face immersion in cold water. (D) PEMI-DR session: the same protocol used for A with 60 s of BH with face immersion in cold water during the first minute of PEMI. Stroke volume (SV), heart rate (HR), and cardiac output (CO) were collected by means of an impedance method. Results: At the end of apnea, HR was decreased in condition C and D with respect to A (−40.8 and −40.3%, respectively vs. −9.1%; p < 0.05). Since SV increase was less pronounced at the same time point (C = +32.4 and D = +21.7% vs. A = +6.0; p < 0.05), CO significantly decreased during C and D with respect to A (−23 and −29.0 vs. −1.4%, respectively; p < 0.05). Conclusion: Results addressed the hypothesis that DR overcame the MM in our setting

Geology and mineralogy of the Auki Crater, Tyrrhena Terra, Mars: A possible post impact-induced hydrothermal system

A variety of hydrothermal environments have been documented in terrestrial impact structures. Due to both past water interactions and meteoritic bombardment on the surface of Mars, several authors have predicted various scenarios that include the formation of hydrothermal systems. Geological and mineralogical evidence of past hydrothermal activity have only recently been found on Mars. Here, we present a geological and mineralogical study of the Auki Crater using the spectral and visible imagery data acquired by the CRISM (Compact Reconnaissance Imaging Spectrometer for Mars), CTX (Context Camera) and HiRISE (High Resolution Imaging Science Experiment) instruments on board the NASA MRO mission. The Auki Crater is a complex crater that is ∼38 km in diameter located in Tyrrhena Terra (96.8°E and 15.7°S) and shows a correlation between its mineralogy and morphology. The presence of minerals, such as smectite, silica, zeolite, serpentine, carbonate and chlorite, associated with morphological structures, such as mounds, polygonal terrains, fractures and veins, suggests that the Auki Crater may have hosted a post impact-induced hydrothermal system. Although the distribution of hydrated minerals in and around the central uplift and the stratigraphic relationships of some morphological units could also be explained by the excavation and exhumation of carbonate-rich bedrock units as a consequence of crater formation, we favor the hypothesis of impact-induced hydrothermal circulation within fractures and subsequent mineral deposition. The hydrothermal system could have been active for a relatively long period of time after the impact, thus producing a potential transient habitable environment. It must be a spectrally neutral component to emphasize the spectral features; It is an average of spectra taken in the same column of the numerator spectra to correct the residual instrument artifacts and reduce detector noise that changes from column to column; It must be taken in the neighborhood of the area of interest to reduce most of the common mineral component. It is not always possible to satisfy all of the criteria listed above and this must be taken into account in the interpretation of the ratioed spectra. Moreover, this procedure works well if the denominator spectra have a phase similar to that of numerator spectra, but, as we will see, that is not always the case. The ratioed spectra may continue to have multiple phases that contribute to the spectrum with its spectral features (Wiseman et al., 2013). For this reason, when we compare a ratioed spectrum with those from the laboratory, it must be taken into account that more phases may continue to affect the band positions.For the geological and morphometric analyses, we used high-resolution imagery and topography from ESA Mars Express and NASA MRO (Mars Reconnaissance Orbiter) missions. In particular, HRSC (High Resolution Stereo Camera, Neukum et al., 2004) data (visible nadir image at 12.5 m/pixel and stereo-derived topography at 100 m/pixel) were used for the overall crater context, while CTX (ConTeXt, Malin et al., 2007) and HiRISE (High Resolution Imaging Science Experiment, McEwen et al., 2007) images supported the detailed analysis of the floor and central part of the crater. The latter two datasets were also used to derive high-resolution topography (down to 7 m/pixel from CTX and 1 m/pixel from HiRISE) through the NASA Stereo Pipeline software (Moratto et al., 2010). All of the data were georeferenced and co-registered using the equirectangular projection and the Mars IAU2000 reference ellipsoid. Finally, the imagery, spectral data and topography were imported into the GIS (Geographic Information System, ArcGIS v.10.2.2) environment to obtain a multitemporal/multisensor/multiscale view of the studied crater. We delineated the map units, taking into account their morphology/morphometry, surface properties, texture at different scales (e.g., relative tonal differences from visible imagery, thermal inertia, rough or smooth texture), and their internal sedimentary structure when possible (from erosional windows, crater walls or scarps). The latter approach allowed us to i) identify the main geological/geomorphological units and to ii) correlate the defined units with the mineralogical observations from CRISM (Figs. 1 and 4).</ce:section

Graphene-based Schottky Device Detecting NH3 at ppm level in Environmental Conditions

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Warming-up the immune cell engagers (ICEs) era in breast cancer: state of the art and future directions

The advent of immune checkpoint inhibitors (ICIs) has deeply reshaped the therapeutic algorithm of triple-negative breast cancer (TNBC). However, there is considerable scope for better engagement of the immune system in other BC subtypes. ICIs have paved the way for investigations into emerging immunotherapeutic strategies, such as immune cell engagers (ICEs) that work by promoting efficient tumor cell killing through the redirection of immune system against cancer cells. Most ICEs are bispecific antibodies that simultaneously recognize and bind to both cancer and immune cells generating an artificial synapse. Major side effects are cytokine release syndrome, hepatotoxicity, and neurotoxicity related to inappropriate immune system activation. Here, we provide a comprehensive overview of this compounds, the available preclinical and clinical evidence supporting their investigation and development in BC also highlighting the challenges that have prevented their widespread use in oncology. Finally, major strategies are explored to broaden their use in BC