This systematic review and meta-analysis were conducted to study the prevalence and pattern of sleep disturbances in children and adolescents during the COVID-19 pandemic.
MEDLINE, EMBASE, and Web of ...Science were searched for original studies describing sleep abnormalities in children and adolescents with or without pre-existing neurobehavioral disorders during the COVID-19 pandemic. The pooled estimates for various sleep abnormalities were calculated using a random-effect model.
Of 371 articles screened, 16 studies were included. Among these, five studies were in preschool children, two were in children with pre-existing neurobehavioral disorders and the remaining were in school going children and adolescents. The outcome measures used for sleep were markedly heterogeneous across the studies.
The pooled prevalence of any sleep disturbance in children during the pandemic was 54%(95%CI:50–57%). Interestingly, the prevalence in pre-school children was lower than pre-pandemic times (RR = 0.87; 95% CI:0.58–1.30) but this was not statistically significant. The pooled prevalence of children not meeting sleep recommendation was 49% (95%CI: 39–58%).
The prevalence of sleep problems in children and adolescents during the COVID-19 pandemic is alarming. Pre-school children had a trend towards relatively fewer sleep disturbances due to home confinement measures in comparison with pre-pandemic times. Sleep duration recommendations were not met in nearly half of healthy children. However, these conclusions need to be seen in light of limited literature on the topic, few included studies done in heterogenous populations, and dubious quality of inferences drawn from these studies which were predominantly online surveys.
CRD42020213788.
•The prevalence of sleep problems in children during COVID-19 pandemic is alarming.•The pooled prevalence of any sleep disturbance was 54% (95%CI:50–57%).•The pooled prevalence of children with worsening of sleep quality was 27% (95%CI:12–49%) and with reduced sleep duration was 16%(95%CI: 5–14%).•The pooled prevalence of children with worsening of sleep quality was 27% (95%CI:12–49%) and with reduced sleep duration was 16%(95%CI: 5–14%).•Pre-school children had a trend towards fewer sleep disturbances when compared with pre-pandemic times.
‘Big data’ is massive amounts of information that can work wonders. It has become a topic of special interest for the past two decades because of a great potential that is hidden in it. Various ...public and private sector industries generate, store, and analyze big data with an aim to improve the services they provide. In the healthcare industry, various sources for big data include hospital records, medical records of patients, results of medical examinations, and devices that are a part of internet of things. Biomedical research also generates a significant portion of big data relevant to public healthcare. This data requires proper management and analysis in order to derive meaningful information. Otherwise, seeking solution by analyzing big data quickly becomes comparable to finding a needle in the haystack. There are various challenges associated with each step of handling big data which can only be surpassed by using high-end computing solutions for big data analysis. That is why, to provide relevant solutions for improving public health, healthcare providers are required to be fully equipped with appropriate infrastructure to systematically generate and analyze big data. An efficient management, analysis, and interpretation of big data can change the game by opening new avenues for modern healthcare. That is exactly why various industries, including the healthcare industry, are taking vigorous steps to convert this potential into better services and financial advantages. With a strong integration of biomedical and healthcare data, modern healthcare organizations can possibly revolutionize the medical therapies and personalized medicine.
Functionalities/coatings on fiber; increased surface energy and surface roughness to promote fiber/matrix adhesion strength.
Carbon fiber reinforcements with an excellent mechanical performance to ...weight ratio are primarily preferred for advanced composite applications. The poor interfacial adhesion between carbon fiber surfaces and polymer molecules caused intrinsically by hydrophobicity and chemical inertness of carbon is a long existing issue to overcome. The article intends to review the research work carried out over the past couple of years in the area of carbon fiber surface modifications and carbon fiber/polymer interfacial adhesion. This paper provides a systematic and up-to-date account of various ‘wet’, ‘dry’ and ‘multi-scale’ fiber surface modification techniques, i.e., sizing, plasma, chemical treatments and carbon nano-tubes/nano-particles coating, for increasing the wettability and interfacial adhesion with polymeric matrices. The review highlights strategies for retaining the carbon fiber mechanical strength after surface modification and stresses its significance.
Glucagon‐like peptide 1 (GLP‐1) is a growth factor that has demonstrated neuroprotective properties in a range of studies. In an APPswe/PS1ΔE9 mouse model of Alzheimer's disease (AD), we previously ...found protective effects on memory formation, synaptic plasticity, synapse survival and a reduction of amyloid synthesis and plaque load in the brain. Here, we analyse the neuroprotective properties of the GLP‐1 analogue liraglutide in human neuroblastoma cell line SH‐SY5Y during methyl glyoxal stress. We show for the first time that cell viability was enhanced by liraglutide (XTT assay) in a dose‐dependent way, while cytotoxicity (LDH assay) and apoptosis were reduced. Expression of the pro‐survival Mcl1 signaling protein was increased, as was activation of cell survival kinases Akt, MEK1/2 and the transcription factor p90RSK. Liraglutide also decreased pro‐apoptotic Bax and Bik expression. In addition, the membrane potential and the influx of calcium into the cell were enhanced by liraglutide. GLP‐1 receptor expression was also increased by the drug. The results demonstrate a range of growth factor‐related cytoprotective processes induced by liraglutide, which is currently on the market as a treatment for type 2 diabetes (Victoza®). It is also tested in clinical trials in patients with Alzheimer disease.
We investigated the neuroprotective properties of the GLP‐1 analogue liraglutide in SH‐SY5Y cells during methyl glyoxal stress. Cell survival was enhanced, while cytotoxicity and apoptosis was reduced. Expression of the pro‐survival Mcl1 signaling protein, activation of Akt, MEK1/2 and the transcription factor p90RSK was increased. Pro‐apoptotic Bax and Bik expression was reduced, and the influx of calcium into the cell was normalised. The results demonstrate a range of growth factor related cytoprotective processes induced by the drug liraglutide.
We investigated the neuroprotective properties of the GLP‐1 analogue liraglutide in SH‐SY5Y cells during methyl glyoxal stress. Cell survival was enhanced, while cytotoxicity and apoptosis was reduced. Expression of the pro‐survival Mcl1 signaling protein, activation of Akt, MEK1/2 and the transcription factor p90RSK was increased. Pro‐apoptotic Bax and Bik expression was reduced, and the influx of calcium into the cell was normalised. The results demonstrate a range of growth factor related cytoprotective processes induced by the drug liraglutide.
Abstract
We present a detailed study of structural, magnetic and thermodynamic properties of a series of Heusler alloys Fe
2-x
Mn
x
CrAl (x = 0, 0.25, 0.5, 0.75 and 1). Structural investigation of ...this series is carried out using high resolution synchrotron X-ray diffraction. Results suggest that with increasing Mn concentration, the
L
2
1
structure of Fe
2
CrAl is destabilized. The DC magnetization results show a decrement in paramagnetic (PM) to ferromagnetic (FM) phase transition temperature (
T
C
) with increasing Mn concentration. From the systematic analysis of magnetic memory effect, heat capacity, time dependent magnetization, and DC field dependent AC susceptibility studies it is observed that, Fe
2
CrAl exhibits cluster glass(CG)-like transition approximately at 3.9 K (
T
f2
). The alloys, Fe
1.75
Mn
0.25
CrAl and Fe
1.5
Mn
0.5
CrAl exhibit double CG-like transitions near
T
f1
~ 22 K,
T
f2
~ 4.2 K and
T
f1
~ 30.4 K,
T
f2
~ 9.5 K respectively, however, in Fe
1.25
Mn
0.75
CrAl, a single CG-like transition is noted at
T
f2
~ 11.5 K below
T
C
. Interestingly, FeMnCrAl shows the absence of long ranged magnetic ordering and this alloy undergoes three CG-like transitions at ~22 K (
T
f
*
), 16.6 K (
T
f1
) and 11 K (
T
f2
). At high temperatures, a detailed analysis of temperature response of inverse DC susceptibility clearly reveals the observation of Griffiths phase (GP) above 300 K (
T
*) in Fe
2
CrAl and this phase persists with Mn concentration with a decrement in
T
*.
In this paper, we develop a multi-agent reinforcement learning (MARL) framework to obtain online power control policies for a large energy harvesting (EH) multiple access channel, when only causal ...information about the EH process and wireless channel is available. In the proposed framework, we model the online power control problem as a discrete-time mean-field game (MFG), and analytically show that the MFG has a unique stationary solution. Next, we leverage the fictitious play property of the mean-field games, and the deep reinforcement learning technique to learn the stationary solution of the game, in a completely distributed fashion. We analytically show that the proposed procedure converges to the unique stationary solution of the MFG. This, in turn, ensures that the optimal policies can be learned in a completely distributed fashion. In order to benchmark the performance of the distributed policies, we also develop a deep neural network (DNN) based centralized as well as distributed online power control schemes. Our simulation results show the efficacy of the proposed power control policies. In particular, the DNN based centralized power control policies provide a very good performance for large EH networks for which the design of optimal policies is intractable using the conventional methods such as Markov decision processes. Further, performance of both the distributed policies is close to the throughput achieved by the centralized policies.
•A compliant TLD is proposed to facilitate tuning and vibration control of short period structures.•TLD parameters are optimized and improved performance over conventional TLD is established.•The ...effectiveness of the response control is demonstrated by numerical simulation.•Findings from simulation are substantiated experimentally by shake table testing.•Effectiveness of the proposed TLD is demonstrated in a real building.
Tuning of sloshing frequency of liquid to short period structures possess challenges in Tuned Liquid Dampers (TLD). However, seismic vulnerability of short period structures cannot be overemphasized. In such instances, frequency tuning is facilitated by inserting a spring between the structure and the TLD. An implementation of this is presented herein by mounting the TLD on an array of compliant elastomeric pads, referred herein as compliant TLD. The effectiveness of compliant TLD is demonstrated through simulation that involve numerical solution of the derived equation of motion. The nonlinear sloshing, wave breaking and resulting dissipation are described by Sun's model. The infeasibility of tuning of conventional TLD to short period structures and consequent inefficiency are shown to be largely eliminated by the proposed implementation. Significant reductions in the peak and root mean square (r.m.s) floor accelerations and storey displacements are observed while (the structures are) subjected to a suite of ground motions pertaining to varying hazard level. The parameters for the proposed system are chosen based on the parametric variations of the controlled responses. The performances of the compliant TLD are also verified with experimental investigations using shake table test on scaled model of a building-TLD system. The experimental results corroborate with the trends observed from simulation. The tuning invoked by the compliant mechanism is observed to largely retain the sloshing and dissipation through wave breaking. Further, the design of the compliant TLD is presented and enumerated with an example of realistic building frame.
This review highlights the development of energy saving transparent heat regulating (THR) materials and coating for energy saving window applications. Current state-of-the-art technologies including ...transparent heat reflecting mirror (THM), thermo-chromic (TC). transparent solar cells (TSC), and luminescent based materials have been discussed. The coating performance primarily depends on the selection of materials, surface and structural morphology, dielectric passivation growth process and architecture of the multi-layered structure. The micro-structural properties of thin metal/metal oxide layer, and its impact on the heat reflecting coating have been studied extensively. Growth of high quality continuous thin film with fewer defects is an essential part of the infrared reflecting and/or heat regulating coatings. Henceforth, in this review, detailed analysis of growth of continuous and thin metal layer influence of the seed layer (germanium and nickel) and doping on the growth mechanism of thin metal have been discussed. Surface morphology and electronic properties of metal layer/multi-layered coatings have been studied in detail for THR applications. A wide range of metal oxides and their physical properties have been considered for use as passivation layer in the THR coating structure. Among several THR structures, the architecture comprising of dielectric-metal-dielectric (DMD) stack is known to exhibit the best heat reflecting performances. While the metal component typically comprises of silver (Ag), copper (Cu), and nitride based materials, dielectrics are made from metal oxides such as BaSnO3, TiO2, SnO2, ZnO, HfO2, Cu2O, and ZrO2. Selection of passivation layer and tuning of micro-structural properties are very crucial to enhance the visible transmittance without sacrificing infrared reflectance. Optical properties of the dielectric layer can be controlled with growth mechanism and varying content of impurity dopant. Metal doped dielectrics play a key role to enhance the visible light transmission while maintaining infra-red reflection. Through in-situ materials engineering, crystal quality of the dielectric improves which has significant role on the THR performance. Furthermore, impact of rapid thermal annealing (RTA) technique to improve crystal quality of metal oxides without oxidizing the thin metal layer is also emphasized. In the subsequent sections, synthesis of thin films by using sputtering methods, thermal evaporation and e-beam evaporation methods using inexpensive materials for large scale deployment of coating have been discussed. Neutral colored Cu-based THR smart windows is developed through tuning the structural property of TiO2. The simulated Cu-based THR window shows >10 CC temperature reduction when compared to conventional glass based windows. Thermal stability of copper and silver based multilayer enhanced through ultra-thin metal and dielectric interface engineering. Transparent conducting oxides (TCOs) are also an essential candidate for the wide band gap semiconductor based THR application. Recent progress in TCOs material has been briefly discussed in one of the section of the review. Hetero-epitaxy of metal oxides (ITO/ZnO) shows promising characteristics as heat insulating materials. Impact of growth process and surface morphology of the TCO have been studied to evaluate the performance of the TCO as heat insulating materials. In addition, advanced hybrid composite based heat reflector coatings for energy efficient building applications is also highlighted in the later section of the review. The industrial utilization and efficacy of heat reflector metal oxides, when incorporated into poiymeric/pigments/fibers and heat reflecting durable paints as advanced hybrid composites coatings has been discussed. The progression of solution based metal nanowire (MNW) and optical properties for the heat regulating applications have been included. Dielectric/metal-NW/dielectric multilayer can be a potential candidate for the development of low cost THR film. The solution based THR methods has potential to be mass customized in economic ways and can be viable at industrial scale. Thermo-chromic materials are also considered as prospective candidate for the transparent coating applications. Recent development of VO2 bilayer, trilayer, micro-pattern and nano-plate films have been discusses to enhance the luminous transmittance and solar modulation ability. Transparent solar cells, based on the infra-red absorption through up-conversion nanoparticles are viable candidates for the development of environmental friendly heat regulating systems. Recent advancement of inorganic, polymer, perovskite, and luminescent based transparent solar cell (TSCs) with heat reflecting mirror have been evaluated for smart windows applications. For the deployment of large scale THR film, low cost materials, roll-to-roll (R2R) sputter and atmospheric pressure chemical vapour deposition (APCVD) have been assessed for the industrial applicability. The progression of THR materials with thermo-chromics, self-cleaning and TSCs materials can enhance the overall performance of the smart/transparent coatings for thermal management and heat regulating functionalities.
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