Central Compact Objects (CCOs) are a handful of sources located close to the geometrical center of young supernova remnants. They only show thermal-like, soft X-ray emission and have no counterparts ...at any other wavelength. While the first observed CCO turned out to be a very peculiar magnetar, discovery that three members of the family are weakly magnetised Isolated Neutron Stars (INSs) set the basis for an interpretation of the class. However, the phenomeology of CCOs and their relationship with other classes of INSs, possibly ruled by supernova fall-back accretion, are still far from being well understood.
Statistical analysis of the eigenfunctions of the Anderson tight-binding model with on-site disorder on regular random graphs strongly suggests that the extended states are multifractal at any finite ...disorder. The spectrum of fractal dimensions f(α) defined in Eq. (3) remains positive for α noticeably far from 1 even when the disorder is several times weaker than the one which leads to the Anderson localization; i.e., the ergodicity can be reached only in the absence of disorder. The one-particle multifractality on the Bethe lattice signals on a possible inapplicability of the equipartition law to a generic many-body quantum system as long as it remains isolated.
ABSTRACT The 6.67 hr periodicity and the variable X-ray flux of the central compact object (CCO) at the center of the supernova remnant RCW 103, named 1E 161348-5055, have been always difficult to ...interpret within the standard scenarios of an isolated neutron star (NS) or a binary system. On 2016 June 22, the Burst Alert Telescope (BAT) on board Swift detected a magnetar-like short X-ray burst from the direction of 1E 161348-5055, also coincident with a large long-term X-ray outburst. Here, we report on Chandra, Nuclear Spectroscopic Telescope Array, and Swift (BAT and XRT) observations of this peculiar source during its 2016 outburst peak. In particular, we study the properties of this magnetar-like burst, we discover a hard X-ray tail in the CCO spectrum during outburst, and we study its long-term outburst history (from 1999 to 2016 July). We find the emission properties of 1E 161348-5055 consistent with it being a magnetar. However, in this scenario, the 6.67 hr periodicity can only be interpreted as the rotation period of this strongly magnetized NS, which therefore represents the slowest pulsar ever detected, by orders of magnitude. We briefly discuss the viable slow-down scenarios, favoring a picture involving a period of fall-back accretion after the supernova explosion, similarly to what is invoked (although in a different regime) to explain the "anti-magnetar" scenario for other CCOs.
•A dynamic model to estimate the energy performance of buildings is presented.•The model is validated against leading software packages, TRNSYS and Energy Plus.•Modified degree days are introduced to ...account for solar irradiation effects.
Degree days represent a versatile climatic indicator which is commonly used in building energy performance analysis.
In this context, the present paper proposes a simple dynamic model to simulate heating/cooling energy consumption in buildings. The model consists of several transient energy balance equations for external walls and internal air according to a lumped-capacitance approach and it has been implemented utilizing the Matlab/Simulink® platform. Results are validated by comparison to the outcomes of leading software packages, TRNSYS and Energy Plus.
By using the above mentioned model, energy consumption for heating/cooling is analyzed in different locations, showing that for low degree days the inertia effect assumes a paramount importance, affecting the common linear behavior of the building consumption against the standard degree days, especially for cooling energy demand.
Cooling energy demand at low cooling degree days (CDDs) is deeply analyzed, highlighting that in this situation other factors, such as solar irradiation, have an important role. To take into account these effects, a correction to CDD is proposed, demonstrating that by considering all the contributions the linear relationship between energy consumption and degree days is maintained.
•The internal environment (IE) presumably supports the theory of homeostasis (TOH).•However, IE axioms have empirical and logical shortcomings.•In addition, “stability” has different, even opposite, ...meanings for IE and TOH.•Therefore, the theory of IE does not support the TOH.
The objective of this critique is to demonstrate that the theory of “internal environment” (TIE) does not support the theory of “homeostasis” (TOH). We review and conclude that remains valid the concept of “internal environment”, which corresponds anatomically to the extracellular fluid (ECF) that bathes tissue cells. The Claude Bernard's classification of “life”, a corollary of the TIE under a strict “reactive” paradigm, we then interpret as a classification of how animals behave in response to environmental changes. According to such interpretation, the two theories agree that, when facing changes in the external environment, animals with “free” behavior regulate essential metabolism factors present in the ECF. These are “internalized environmental factors” or IEF (temperature, O2, water, and basic organic and inorganic “nutrients”), a marine legacy of the evolution of the body fluid compartments. However, we show that have empirical and logical shortcomings key inferences derived from the TIE. Such inferences representing traditional premises of TOH we summarize here in two axioms: “if free behavior then regulated IEF” and “all behavioral mechanisms regulate the IEF”. In addition, whereas “stability” means “free behavior versus dormancy” in TIE, it means “tissue cells that resist destruction” in TOH. This leads to inevitable contradictions, here discussed at length, that reduce the scope of TOH. We might be in need of a theory that considers not only where TIE and TOH are superficially valid, but also where they crucially diverge, in order to explain “stability” as applied to physiology and behavior.
The melanocortin 4 receptor (MC4R) is a G protein-coupled receptor whose disruption causes obesity. We functionally characterized 61 MC4R variants identified in 0.5 million people from UK Biobank and ...examined their associations with body mass index (BMI) and obesity-related cardiometabolic diseases. We found that the maximal efficacy of β-arrestin recruitment to MC4R, rather than canonical Gαs-mediated cyclic adenosine-monophosphate production, explained 88% of the variance in the association of MC4R variants with BMI. While most MC4R variants caused loss of function, a subset caused gain of function; these variants were associated with significantly lower BMI and lower odds of obesity, type 2 diabetes, and coronary artery disease. Protective associations were driven by MC4R variants exhibiting signaling bias toward β-arrestin recruitment and increased mitogen-activated protein kinase pathway activation. Harnessing β-arrestin-biased MC4R signaling may represent an effective strategy for weight loss and the treatment of obesity-related cardiometabolic diseases.
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•61 variants in the Melanocortin-4 Receptor gene were found in 0.5 million people•Variants causing a gain of function were associated with protection from obesity•Variants biased toward β-arrestin signaling mediated the protective effects
Gain-of-function genetic variants in the Melanocortin-4 Receptor associated with protection against obesity exhibit signaling bias for the recruitment of β-arrestin rather than canonical Gαs-mediated cAMP production.
The detailed analysis of a solar collector is a complex task, due to the high number of parameters affecting its performance. In the last 40 years, several dynamic procedures have been developed and ...tested using numerical approaches, to obtain the behavior of the thermal solar collector without performing the set of complicated and expensive experimental tests usually adopted in steady-state approaches. Moreover, thanks to the improvement of the computing performance, these numerical models provide useful tools in reproducing for complex system behavior. In fact, when multiple energy sources are coupled together to build integrated systems (i.e., Solar-Assisted Heat Pumps, Ground-Source Solar-Assisted Heat Pump, etc.) the dynamics of each equipment has an noticeable influence on the behavior of the whole system. Therefore, these tools can be also profitably used to develop and optimize dynamic control criteria for these systems. In this context, a great effort has been made in the last years to improve the predictive potential of the dynamic models for solar collectors. Finally, thanks to the increase of the computational performance in the last years, Computational Fluid-Dynamics (CFD) approach has become a powerful tool to investigate the heat transfer phenomena. A lot of works have been made using both commercial and in-house developed codes, investigating several aspects concerning the heat transfer mechanism in a solar collector.
In the present work, an updated review of models for flat-plate thermal solar collectors is presented, including a proper classification and a description of their main characteristics and performance. A short description of the main works involving CFD analysis on thermal solar collectors is reported too.
Determining how cells vary with their local signaling environment and organize into distinct cellular communities is critical for understanding processes as diverse as development, aging, and cancer. ...Here we introduce EcoTyper, a machine learning framework for large-scale identification and validation of cell states and multicellular communities from bulk, single-cell, and spatially resolved gene expression data. When applied to 12 major cell lineages across 16 types of human carcinoma, EcoTyper identified 69 transcriptionally defined cell states. Most states were specific to neoplastic tissue, ubiquitous across tumor types, and significantly prognostic. By analyzing cell-state co-occurrence patterns, we discovered ten clinically distinct multicellular communities with unexpectedly strong conservation, including three with myeloid and stromal elements linked to adverse survival, one enriched in normal tissue, and two associated with early cancer development. This study elucidates fundamental units of cellular organization in human carcinoma and provides a framework for large-scale profiling of cellular ecosystems in any tissue.
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•EcoTyper enables large-scale profiling of cell states and multicellular ecosystems•Applicable to bulk, single-cell, and spatially resolved gene expression data•A reference atlas of 69 cell states and 10 ecosystems across 16 types of carcinoma•Carcinoma ecosystems have distinct biology, clinical outcomes, and spatial topology
EcoTyper, a machine learning framework for identifying and characterizing cell states and ecosystems from gene expression data, yields insights into the cellular landscape and community structure of human carcinoma, the leading cause of cancer-related mortality.
MicroRNA (miRNA) has shown to enhance or inhibit cell proliferation, differentiation and activity of different cell types in bone tissue. The discovery of miRNA actions and their targets has helped ...to identify them as novel regulations actors in bone. Various studies have shown that miRNA deregulation mediates the progression of bone-related pathologies, such as osteoporosis.
The present review intends to give an exhaustive overview of miRNAs with experimentally validated targets involved in bone homeostasis and highlight their possible role in osteoporosis development. Moreover, the review analyzes miRNAs identified in clinical trials and involved in osteoporosis.
•Review of miRNAs in osteogenic pathways•Review of miRNAs in osteoclastogenic pathways•Review of circulating miRNAs implicated in osteoporosis•Identification of circulating miRNAs as possible markers of osteoporosis
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