F0X01 Regulation of Islet Cell Development in the Human Fetal Pancreas.

Recent studies have outlined a major role for the forkhead protein FOXOl in (3- cell differentiation, proliferation, and stress resistance in the adult islet. The objective of this study was to characterize the expression pattern and function of FOXOl during human fetal islet cell development (8 to 21 weeks of fetal age). Using immunostaining, FOXOl co-localized with ductal and endocrine cell markers, in addition to PDX-1 and NGN3 transcription factors throughout development. In vitro, nuclear export of FOXOl occurred in islet-epithelial cell clusters (18 to 21 wks) exposed to high insulin concentrations in a PI3-Kinase/AKT dependent manner. Cells transfected with FOXOl siRNA demonstrated an up-regulation in NGN3 and NKX6-1 mRNA levels and protein cellular distribution in parallel with an increase in the (3-cell population, a down- regulation in the NGN3 inhibitory factor HES1, and no effect on PDX-1. In conclusion, these results outline a role by which FOXOl may contribute to islet cell development

An Approach to Conserve Gaza Architectural Heritage Through Digital Technology

Heritage is considered as one of the constituents that preserve culture and national identity of any community. This is because heritage is a witness of accumulating experiences of that community. During recent years, architectural styles have changed dramatically in our country. Modern and western styles of housing prevailed so much that the Palestinian heritage touches nearly disappeared. In addition, many of the historic buildings in Gaza City have been destroyed due to the lack of public awareness about the importance of this heritage. This situation created the need for restoring the inveterate Palestinian culture and heritage through 3D Visualizing of Architectural Heritage. Awareness of cultural heritage through publicizing the digitized simulation of this heritage by using virtual reality and 3D modelling and animation techni-ques would help in preserving it and achieving balanced environment which reflects both originality of past and modernity of contemporaneity

Identification Techniques Applied to a Passive Elasto-magnetic Suspension

The paper presents an experimental passive elasto-magnetic suspension based on rare-earth permanent magnets, characterized by negligible dependence on mass of its natural frequency. The nonlinear behaviour of this system, equipped with a traditional linear elastic spring coupled to a magnetic spring, is analysed in time domain, for non-zero initial conditions, and in frequency domain, by applying sweep excitations to the test rig base. The dynamics of the system is very complex in dependence of the magnetic contribution, showing both hardening behaviour in the elasto-magnetic setup, and softening motion amplitude dependent behaviour in the purely magnetic case. Hence it is necessary to adopt nonlinear identification techniques, such as non-parametric restoring force mapping method and direct parametric estimation technique, in order to identify the system parameters in the different configurations. Finally, it is discussed the ability of identified versus analytical models in reproducing the nonlinear dependency of frequency on motion amplitude and the presence of jump phenomen

Heart ventricular histology and microvasculature together with aortic histology and elastic lamellar structure: A comparison of a novel dual-purpose to a broiler chicken line

The use of dual-purpose chickens is a strategy to avoid killing one-day-old male chicks of egg laying lines. Lohmann Dual (LD) is a novel dual-purpose chicken line created by the crossbreeding of layer and broiler lines. However, many of the cardiovascular diseases of broilers are likely to be associated with intensive genetic selection for growth and feed conversion efficiency. This study aimed to compare the macroscopic and microscopic structure of the heart and the aorta of the LD chicken line with that of the broiler chicken line, Ross 308 (Ross) under typical husbandry conditions for meat production. Eighty, one-day-old male chicks of each line were housed for 5 weeks (Ross) and 9 weeks (LD). Six birds of each line were sampled weekly. Heart mass, thickness of ventricular walls, cardiomyocyte size and blood capillary density as well as aortic diameter and thickness, number of elastic lamellae and elastic fiber percentage in the aortic wall were determined. The growth patterns of the heart were the same in the two lines. Although LD chickens had a lower absolute heart mass than that of Ross chickens, the relative heart mass in both lines was similar. The cardiomyocytes of LD chickens were larger than those of Ross’s of the same body weight (BW), nevertheless both lines had similar thicknesses of their ventricular walls. The blood capillary density was greater in the LD heart than in that of the Ross heart. The aorta of LD chickens had proportionally; a greater aortic lumen radius, larger numbers of elastic lamellae and more elastic fibers than in Ross chickens. Our results suggest that the heart and aorta of the LD chickens have not been disadvantaged by their intensive genetic selection; furthermore, LD chickens have a better myocardial capillary supply and better aortic mechanical properties than those of Ross chickens

Langendorff’s isolated perfused rat heart technique: a review

The Langendorff’s isolated perfused small mammalian heart represents the optimal compromise in the conflict between the quantity and quality of data that can be acquired from an experimental model versus its clinical relevance, especially in relation to ischemia-reperfusion injury. We analyzed the important recent, as well as standard older articles to highlight the importance of Langendorff’s isolated heart technique using the rat as an experimental animal model. The retrograde perfusion of isolated rat heart preparation is the most commonly used technique in cardiovascular research experiments with many advantages. The longevity of this preparation is one of the main advantages. From the moment an ex vivo preparation is established, it starts to deteriorate and the rate will depend on number of factors such as the skill of the operator, the species of animal, age, initial heart rate, choice and composition of the perfusion fluid, flow rate, presence or absence of various drugs, preload pressure, and the temperature at which the studies are carried out. Recently, various techniques and variables measured have undergone modifications. This review article has attempted to address many of the issues, developments, and applications which will assist investigators to make the best possible use of this experimental model using the rat

Spectrum Assignment in Hardware-Constrained Cognitive Radio IoT Networks Under Varying Channel-Quality Conditions

[EN] The integration of cognitive radio (CR) technology with the future Internet-of-Things (IoT) architecture is expected to allow effective massive IoT deployment by providing huge spectrum opportunities to the IoT devices. Several communication protocols have been proposed for the CR networks while ignoring the adjacent channel interference (ACI) problem by assuming sharp filters at the transmit and receive chains of each CR device. However, in practice, such an assumption is not feasible for low-cost hardware-constrained CR-capable IoT (CR-IoT) devices. Specifically, when a large number of CR-IoT devices are operating in the same vicinity, guard-band channels (GBs) are needed to mitigate the ACI problem, introducing GB adds constraints on the efficient use of spectrum and protocol design. In this paper, we develop a channel assignment mechanism for the hardware-constrained CR-IoT networks under time-varying channel conditions with GB-awareness. The objective of our assignment is to serve the largest possible number of CR-IoT devices by assigning the least number of idle channels to each device subject to rate demand and interference constraints. The proposed channel assignment in this paper is conducted on a per-block basis for the contending CR-IoT devices while considering the time-varying channel conditions for each CRIoT transmission over each idle channel, such that spectrum efficiency is improved. Specifically, our channel assignment problem is formulated as a binary linear programming problem, which is NP-hard. Thus, we propose a polynomial-time solution using a sequential fixing algorithm that achieves a suboptimal solution. The simulation results demonstrate that our proposed assignment provides significant increase in the number of served IoT devices over existing assignment mechanisms.This work was supported in part by the QR Global Challenges Research Fund, Staffordshire University, Staffordshire, U.K.Salameh, HAB.; Al-Masri, S.; Benkhelifa, E.; Lloret, J. (2019). Spectrum Assignment in Hardware-Constrained Cognitive Radio IoT Networks Under Varying Channel-Quality Conditions. IEEE Access. 7:42816-42825. https://doi.org/10.1109/ACCESS.2019.2901902S4281642825

The Readiness of Government Schools to Deal with the Emergency and Crisis Situations from School Administrators View Point

The study aimed to identify the readiness of government schools to deal with emergency situations and crises from the viewpoint of their administrators. Totaling (326) male and female administrators, the sample was randomly chosen during the first semester (2018/2019), and a tool was developed consisting of (26) items distributed in three domains. The results showed that the estimates of the sample members on all domains came with a high degree of readiness, and showed that there are statistically significant differences attributable to the variable of the school gender and in favor of males, and the presence of statistically significant differences attributable to variable years of experience and in favor (from 10-5 years, and more than 10 years), and the absence of statistically significant differences attributable to the variable of the academic qualification with the exception of the domain of preparedness and prevention and in favor of postgraduate, and the presence of statistical differences due to the variable of the school level and in favor of the (secondary) schools. The study recommends employing early warning devices to detect any emergency occurring in educational institutions

A pilot Citizens' Assembly on Electricity and Energy Justice in Hamra, Lebanon

The Citizens’ Assembly Pilot (CA) on energy justice and electricity was a conceptual and a methodological experiment conducted over five sessions over three days in the neighborhood of Hamra and Beirut in October and November 2020. The CA aimed at exploring meanings, dimensions, priorities of energy justice in a deliberative democratic setting. The CA tackled five main questions: How did we get to where we are? What is energy justice to us? What is the energy-mix we would like to have? What do we need to be doing as individuals and communities to achieve a better energy future? How should we move forward with our decisions on the above questions? The responses produced interesting findings for researchers and international stakeholders to consider further; such as skepticism over renewable energy targets, the interest in circular solutions to solve multiple intersecting service sectors like waste and water in particular. It also raised questions over decentralization as well as privatization at different scales of governance

A novel implementation for generator rotor angle stability prediction using an adaptive artificial neural network application for dynamic security assessment

This paper addresses a new approach for predicting the generator rotor angle using an adaptive artificial neural network (AANN) for power system stability. The aim of this work is to predict the stability status for each generator when the system is under a contingency. This is based on the initial condition of an operating point, which is represented by the generator rotor angle at a certain load level. An automatic data generation algorithm is developed for the training and testing process. The proposed method has been successfully tested on the IEEE 9-bus test system and the 87-bus system for Peninsular Malaysia