Connexins: a myriad of functions extending beyond assembly of gap junction channels

Connexins constitute a large family of trans-membrane proteins that allow intercellular communication and the transfer of ions and small signaling molecules between cells. Recent studies have revealed complex translational and post-translational mechanisms that regulate connexin synthesis, maturation, membrane transport and degradation that in turn modulate gap junction intercellular communication. With the growing myriad of connexin interacting proteins, including cytoskeletal elements, junctional proteins, and enzymes, gap junctions are now perceived, not only as channels between neighboring cells, but as signaling complexes that regulate cell function and transformation. Connexins have also been shown to form functional hemichannels and have roles altogether independent of channel functions, where they exert their effects on proliferation and other aspects of life and death of the cell through mostly-undefined mechanisms. This review provides an updated overview of current knowledge of connexins and their interacting proteins, and it describes connexin modulation in disease and tumorigenesis

Connecting Numerical Relativity and Data Analysis of Gravitational Wave Detectors

Gravitational waves deliver information in exquisite detail about astrophysical phenomena, among them the collision of two black holes, a system completely invisible to the eyes of electromagnetic telescopes. Models that predict gravitational wave signals from likely sources are crucial for the success of this endeavor. Modeling binary black hole sources of gravitational radiation requires solving the Eintein equations of General Relativity using powerful computer hardware and sophisticated numerical algorithms. This proceeding presents where we are in understanding ground-based gravitational waves resulting from the merger of black holes and the implications of these sources for the advent of gravitational-wave astronomy.Comment: Appeared in the Proceedings of 2014 Sant Cugat Forum on Astrophysics. Astrophysics and Space Science Proceedings, ed. C.Sopuerta (Berlin: Springer-Verlag

Laminin and biomimetic extracellular elasticity enhance functional differentiation in mammary epithelia

In the mammary gland, epithelial cells are embedded in a ‘soft' environment and become functionally differentiated in culture when exposed to a laminin-rich extracellular matrix gel. Here, we define the processes by which mammary epithelial cells integrate biochemical and mechanical extracellular cues to maintain their differentiated phenotype. We used single cells cultured on top of gels in conditions permissive for β-casein expression using atomic force microscopy to measure the elasticity of the cells and their underlying substrata. We found that maintenance of β-casein expression required both laminin signalling and a ‘soft' extracellular matrix, as is the case in normal tissues in vivo, and biomimetic intracellular elasticity, as is the case in primary mammary epithelial organoids. Conversely, two hallmarks of breast cancer development, stiffening of the extracellular matrix and loss of laminin signalling, led to the loss of β-casein expression and non-biomimetic intracellular elasticity. Our data indicate that tissue-specific gene expression is controlled by both the tissues' unique biochemical milieu and mechanical properties, processes involved in maintenance of tissue integrity and protection against tumorigenesis

The third post-Newtonian gravitational wave polarisations and associated spherical harmonic modes for inspiralling compact binaries in quasi-circular orbits

The gravitational waveform (GWF) generated by inspiralling compact binaries moving in quasi-circular orbits is computed at the third post-Newtonian (3PN) approximation to general relativity. Our motivation is two-fold: (i) To provide accurate templates for the data analysis of gravitational wave inspiral signals in laser interferometric detectors; (ii) To provide the associated spin-weighted spherical harmonic decomposition to facilitate comparison and match of the high post-Newtonian prediction for the inspiral waveform to the numerically-generated waveforms for the merger and ringdown. This extension of the GWF by half a PN order (with respect to previous work at 2.5PN order) is based on the algorithm of the multipolar post-Minkowskian formalism, and mandates the computation of the relations between the radiative, canonical and source multipole moments for general sources at 3PN order. We also obtain the 3PN extension of the source multipole moments in the case of compact binaries, and compute the contributions of hereditary terms (tails, tails-of-tails and memory integrals) up to 3PN order. The end results are given for both the complete plus and cross polarizations and the separate spin-weighted spherical harmonic modes.Comment: includes corrections to be published in an erratum; the changes are: in Eq (5.15b), -484/105 -> -188/35; in Eq (8.9g), 81127/10080 -> 1369/160; Eq (8.10g), -48239/5040 -> -2419/240; Eq (9.4b), -995/84 -> -353/2

The performance of a heat pipe based solar PV/T roof collector and its potential contribution in district heating applications

Photovoltaic–thermal water collectors have the ability to convert solar energy into electricity and heat, simultaneously. Furthermore, the combination of photovoltaic–thermal solar collectors with a water cooling system can increase significantly the electrical and thermal efficiencies of the system, which can improve the total thermal efficiency of buildings. In this paper, the findings of six experimental configurations of solar-thermal collectors are presented and analysed. Five of the solar-thermal panel configurations were implemented with a cooling cycle. Two of the solar-thermal panels were equipped with monocrystalline silicon modules, the other two collectors were equipped with polycrystalline silicone modules, one of the collectors was based on heat pipe technology and was equipped with a cooling system, while the last collector did not include any cooling cycle. The duration of the experiments was four days during the September of 2014 and they were conducted under different solar radiation conditions. The second part of the paper presents the simulation results for five of the solar-thermal panels connected with a cooling water tank (volume of 500 litre), a domestic hot water tank (volume 350 litre) and a water-water heat pump, in terms of covering the hot water demands of a single family dwelling. The results showed that the hybrid solar collectors would be able to cover approximately 60% of the dwelling’s hot water needs for days with low levels of solar radiation, while for days with high solar radiation they could cover the hot water requirements of the family by 100%

Prevalence of Malnutrition among Syrian Refugee Children from Lebanon

Today, the situation of Syrian refugees is one of the world’s worst humanitarian crises. To estimate the prevalence of malnutrition among pediatric populations of Syrian refugees, 176 Syrian refugee children, with stays of more than two years at three refugee camps (Zalhé, Deddeh, and Kfar Jouz) or from the town of Yohmor, Lebanon were authorized by their parents to participate in this study. The children were anthropometrically evaluated and height-for-age Z-score (HAZ), weight-for-age Z-score (WAZ), and weight-for-height (WHZ) Z-scores were obtained and compared with WHO standards. Furthermore, mid-upper arm circumference (MUAC) was analyzed for screening children 6–59 months old. According to the anthropometric measures, no child met the criteria for chronic, global, acute malnutrition (CGAM), severe acute malnutrition (SAM), or moderate acute malnutrition (MAM). In the total sample, 49.4% of participants were moderately thin, with girls presenting a higher prevalence of thinness than that of boys. Thus, the absence of high rates of malnutrition was verified despite the magnitude of the Syrian refugee’s problem. The data provided by this study identify the need to carry out further research to assess anthropometric growth and nutritional status among long-staying refugee children in order to prevent any health issues that may arise in the future

Overview of the mobility related security challenges in LPWANs

International audienceThe Internet of Things (IoT) is a new emerging system of interconnected devices that experiences significant growth in a wide variety of applications. The rising communication technologies for IoT are the Low Power Wide Area Networks (LPWANs) having long range, low cost and low power characteristics. In this context, an important part of the applications requires the mobility of the end devices with secure communications. In this paper, we consider the mobility management solutions in LPWAN networks and we investigate how they ensure security. We first review the basic IoT security requirements and the typical IoT protocol stack. We then focus on the existing mobility management solutions in LPWAN and we highlight the mobility related security issues by checking the attacks that can be performed in case of mobility. Furthermore, we evaluate the security in each mobility solution by checking the aforementioned attacks and we draw a comparison study

A Neural Network Based Handover for Multi-RAT Heterogeneous Networks with Learning Agent

International audienceThe wireless communication networks continue to evolve with multiple radio access technologies (LTE, WIFI, WIMAX..) included in the same device. Thus, the end-nodes have the flexibility to decide which radio technology to select according to their availability and location. In this case, they must be made intelligent and autonomous enough in order to select automatically the best available wireless technology. Neural Networks represent a promising machine learning technique to be used to make such decisions. The proposed system is implemented on a System on Chip (SoC) integrating both processors and FPGA logic fabrics on the same chip with fast interconnection between them. This allows designing Software/Hardware systems with optimized performance. The adopted SoC offers the partial reconfiguration (PR) feature on the FPGA, which adds more flexibility to these high performance devices. In this paper, we propose a Neural Network based system for heterogeneous networks. The system is based on reinforcement learning that aims to make the system intelligent enough when deciding to perform vertical handover between multiple wireless systems. The switching between the wireless systems standards is implemented using PR technique. © 2018 IEEE