Solar air Collector is used to transform the solar energy into heat energy. Solar heating technologies use only free, renewable and clean energy. More number of previous studies was done. The ...roughness element is changed to enhance the airflow’s capacity to absorb heat. In this study Experimental investigates the glazed solar air heater with quatrefoil shaped artificial roughness is placed above the absorber plate in the solar air heater. The solar air heaters (SAH) with quatrefoil shaped artificial roughness and conventional solar air heater are tested. The outcome indicates that the maximum temperatures for conventional SAH and purposely roughened SAH are 670C and 470C, respectively. By the increased of heat transfer area and increased the turbulence lead to higher heat recovery rate of quatrefoil shaped artificial roughness is 47% more compared to conventional type. The solar air heater is predicted by using Adaptive Neuro Fuzzy Inference System (ANFIS) and accuracy is measured as 90%.
ABSTRACT Odontomes are the most common benign odontogenic tumors of the jaw which are usually slow-growing and non-aggressive. They are generally asymptomatic and diagnosed during routine ...radiographic investigations and are mostly associated with tooth eruption disturbances. The present case series report covers seven cases of odontomes discussing on clinical, radiographic, and histopathologic features (ground section and decalcification) along with a brief review of the literature.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Synthetic petroleum-based products are normally used for food-packaging application which results in environmental pollution. This creates a need to develop biodegradable polymer and polymer-based ...films to maintain the stability of packed materials for a defined period of time that will overcome the drawbacks of the synthetic petroleum-based packaging system. The current work is focussed on evaluating the potential of cellulose agar bio-nanocomposite films in food packaging application. The physical and mechanical properties such as its tensile strength (TS), Young’s modulus (YM) and elongation at break (
E
) were found to be increased on loading with cellulose microfibre (CMF). TS is found to be increased from 38.8 ± 3.2 to 49.4 ± 4.3 and there is about 6% increase in the elongation at break. Similarly, CMF films exhibit 54 ± 0.2% water solubility, 1.304 opacity and 1.71 ± 0.07 GPa, respectively. Also, the bio-nanocomposite film showed less swelling property and an increase in soil degradation rate, enabling it to be applied in food packaging.
Prediction of IoT traffic in the current era has attracted noteworthy attention to utilize the bandwidth and channel capacity optimally. In this paper, the problem of IoT traffic prediction has been ...studied, and solutions have been proposed by using machine learning method ARIMA and learning time series algorithms such as LSTM and gated recurrent unit (GRU-NN) based on neural networks. The proposed GRU-NN predicts the traffic on the basis of transfer learning. The advantage of the GRU-NN over LSTM is also highlighted by solving the problem of gradient disappearance. The proposed GRU-NN memorizes the traffic characteristics of the IoT environment for a long time which eventually helps the system to forecast the upcoming traffic from the existing traces of the traffic. The proposed GRU-NN makes use of the transfer learning technique to handle the problem of insufficient IoT traffic data along with the gradient boosting training method for achieving better accuracy in predicting the network traffic in the IoT environment. The results reveal that the proposed GRU-NN model outperforms the other traffic predictors in terms of statistical performance evaluation parameters such as MAE, RMSE, MRE, and MSE. The results show that the GRU-NN provides the most accurate predictions followed by the LSTM predictor and then ARIMA and other approaches taken up for the comparative study.
Rapid solidification during metal additive manufacturing (AM) leads to non-equilibrium microsegregation, which can result in the formation of detrimental phases and cracking. Most of the ...microsegregation models assume a Scheil-type solidification, where the solidification interface is planar and there exists a local equilibrium at the interface along with either zero or infinite solute diffusion in the respective participating phases—solid and liquid. This assumption leads to errors in prediction. One has to account for finite solute diffusion and the curvature at the dendritic tip for more accurate predictions. In this work, we compare different microsegregation models, that do and do not consider finite diffusion and dendrite tip kinetics, against experiments. We also propose a method to couple dendrite tip kinetics with the diffusion module (DICTRA®) implemented in Thermo-Calc®. The models which accounted for both finite diffusion and dendrite tip kinetics matched well with the experimental data.
In vitro cell viability tests are usually done using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) method. A new spectrofluorometry method was ...developed using acridine orange (AO) and propidium iodide (PI) using multi-label microplate reader. Nine biogenic amines (BAs) histamine (HIM), putrescine (PUT), cadaverine (CAD), 2-phenylethylamine (PHM), tyramine (TYM), tryptamine (TPM), spermine (SPM), spermidine (SPD) and agmatine (AGM) were exposed to RAW 264.7 macrophage in singles at 37°C with 5% carbon dioxide supplementation for 18-24 hours and cell viability was determined using MTS method and AO/PI developed method using dual-spectrofluorometry. Based on MTS assay, SPM and SPD were found to be cytotoxic and it was supported by AO/PI assay. The precedence of disintegration in the nucleus rather than mitochondria upon cell non-viability was also supported by transmission electron microscopy (TEM). The results showed that AO/PI method could be used as an alternative method to determine cytotoxicity besides usual usage in confocal microscopy.
High-strength materials are hard to machine with ordinary tools and necessitates tool inserts of high strength and hardness to machine them. One of the methods to improve the physical properties of ...an insert material is cryogenic treatment which involves the treating of materials at low temperatures. In the current experiments, two multilayer carbide tool inserts WS40PM and F40M were analyzed by cryogenically treating them. Three class of cutting tool inserts were taken for comparison: untreated, cryogenically treated and cryogenically treated and tempered (CTT). The microstructural changes were observed through scanning electron microscopy, and the change in microstructure of all classes of tool inserts was compared and contrasted. Hardness of the tool inserts was measured using Vickers microhardness tester, and the variation of crystallite size in tool inserts was examined through X-ray diffraction studies. Rate of tool wear (through flank wear) was observed by performing shoulder milling operation on the mild steel EN8 grade steel at constant velocity in a CNC vertical machining center using treated and untreated tool inserts. The results showcased the increase in insert hardness, microstructure and tool life of treated tools when compared with untreated tool inserts. Highest hardness was achieved for CTT tool inserts and was found to be 1142 HV for WS40PM and 1483 for F40M inserts, respectively. From the flank wear studies, F40M inserts experienced a wear of 203 µm and WS40PM inserts experienced 269 µm upon machining EN8 grade steel.
•45% of the vaccinated healthcare workers had COVID-19 during the Omicron period in Malaysia•A vaccinated person with a pre-Omicron infection has a lower risk for Omicron infection•Immunity event of ...<90 days lowers Omicron risk, suggesting good timing for the fourth dose
To study the incidence of Omicron infections in Malaysia and the exposures that could reduce the hazard of attaining Omicron infection.
We used a multicenter, prospective cohort to study 482 healthcare workers vaccinated with two and three doses of BNT162b2 for SARS-CoV-2 infection during the Omicron-dominant period in Malaysia.
Between January 31 and July 31, 2022, the cumulative incidence was 44.6% (95% CI 40.2-49.1%), and the incidence rate was 3.33 (95% CI 2.91-3.80) per 1000 person-days. Our study found that protection against Omicron infection was significantly higher for persons with previous SARS-CoV-2 infection (hazard ratio HR 0.41, 95% CI 0.27-0.62) and persons with a more recent immunity event (<30 days reference vs >90 days, HR 3.82, 95%CI 1.34-10.90) from the beginning of the Omicron period.
Pre-Omicron natural infection and a recent immunity event protect against future Omicron infections.
The synthesis of ZnO nanoparticles using biological method is always eco friendly and attractive. The current study focuses on the production of ZnO nanoparticles using the aqueous root extracts of ...Zingiber officinale (ginger). The root extracts were found to be rich in flavonoids which were confirmed by the flavonoid test thereby enhancing the biogenic synthesis of ZnO nanoparticle. The Scanning Electron Microscope with the Energy Dispersive X-ray studies were used for characterization that provides the size and the elemental composition of the synthesized ZnO nanoparticles. The average size of the nanoparticles was found to be 30-50nm. The FTIR analysis played a pivotal role in displaying the important functional groups present in the ZnO nanoparticle, which showed that the sample had strong absorbance in the range of 1600 – 1450 cm-1. Hence the biogenic synthesis of ZnO nanoparticles using Zingiber officinale, can be an alternative to chemical synthesis.
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