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HortScience ◽  
2022 ◽  
Vol 57 (1) ◽  
pp. 154-163
Author(s):  
Ji-Eun Jeong ◽  
Sin-Ae Park

This study was conducted to determine the physiological and psychological benefits of integrating software coding and horticultural activity. Participants included 30 adults in their 20s. The subjects randomly engaged in activities—namely, connecting Arduino components, coding, planting, and a combined coding and horticultural activities. During the activity, two subjective evaluations were conducted at the end of each activity, and participants’ brain waves were measured. The spectral edge frequency 50% of alpha spectrum band (ASEF50) and ratio of sensorimotor rhythm from mid beta to theta (RSMT) were activated in the prefrontal lobe as participants performed combined coding and horticultural activities. When performing these combined activities, relative beta (RB) increased, and relative theta (RT) decreased in the prefrontal lobe. In addition, ASEF50, relative low beta (RLB), and relative mid beta (RMB) were activated during plant-based activities (planting and a combined coding and horticultural activities). The subjective evaluations revealed that the plant-based activities had a positive effect on participants’ emotions. This study shows that activities combining coding and horticulture had a positive impact on physiological relaxation and increased concentration in adults compared with other activities and was also linked with positive subjectively reported emotions.


2021 ◽  
pp. 096739112110350
Author(s):  
Samet Kocabay ◽  
Mehmet Refik Bahar ◽  
Suat Tekin ◽  
Recep Akkaya ◽  
Birnur Akkaya

In the present study, chitosan oligomer was modified to sulfated chitosan oligomer (ShCsO) to mimic heparin. Its chemical structure was determined by infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis. The results showed that the FT-IR spectrum band at 799 cm−1 corresponds to C–O–S and that at 1212 cm−1 corresponds to S=O bond stretching, which prove that the sulfate groups are incorporated into chitosan oligomer successfully. The antimicrobial activity of ShCsO against to Bacillus subtilis in 1% concentration was 89.1 ± 1.7% . The IC50 (μg/ml) of ShCsO was 67.75, 56.07, 85.47, and 84.68 for A2780, MCF-7, DU-145, and HepG2, respectively. The results show that this newly synthesized material is a potential candidate to heparin-like chitosan derivatives. According to the literature, it was the first time that chitosan oligomer was modified to mimic heparin.


Author(s):  
Shijia Sun ◽  
Qi Wei ◽  
Bing-Xuan Li ◽  
Xingjun Shi ◽  
feifei yuan ◽  
...  

The pure and Nd3+-doped YMgB5O10 (YMB, Nd:YMB) crystals were grown successfully by the top-seeded solution growth method with composite fluxes Li2O-B2O3-LiF. The systematic investigation of crystal structure, transmission spectrum, band...


Author(s):  
Н.К. Морозова ◽  
И.Н. Мирошникова

Intense CdS luminescence in the blue and green spectral regions is widely used in all areas of optoelectronics. In this spectrum band are working on lasers CdS. This paper presents the results of a study of the exciton region of the CdS spectrum based on the theory of anti-intersecting bands (bands anticrossing theory - BAC) with the involvement of broader initial data for the analysis of optical properties. Depending on the growth conditions of CdS, the presence and change in the oxygen concentration, as well as the equilibrium of intrinsic point defects, which determines the change in the composition of the crystals. The concept of the nonuniform distribution of isoelectronic centers in the bulk of CdS due to their predominant segregation on compensating stacking faults is introduced. Cathodoluminescence (CL) spectra were studied using various recording methods, excitation intensity and temperature, as well as pulsed CL at high excitation intensities. In a scanning electron microscope from local registration and a high excitation density, the emission of the edge luminescence components of CdS was detected at 300 K To analyze the optical data, we used the capabilities of the method for constructing band models based on the BAC theory, which. collects extensive and multilateral information about specific samples. A model of a CdS O multizone with stacking faults is presented, which determines the spectrum of edge emission. An explanation of the nature of the green edge emission of cadmium sulfide as excitons localized on oxygen-containing complexes in SF layers has been obtained for the first time. It was found that the system of levels of localized excitons at stacking faults does not change either with temperature up to 300 K, or with a change in the oxygen solubility in the crystal to the limiting one. It is shown that the presence of isoelectronic oxygen centers appear itself in the electro-physical properties of crystals. Recommendations are given for the diagnostics of crystals suitable for the creation of luminescent systems or lasers that are stable in operation.


Electronics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2092
Author(s):  
Mahyar TajDini ◽  
Volodymyr Sokolov ◽  
Ievgeniia Kuzminykh ◽  
Stavros Shiaeles ◽  
Bogdan Ghita

Over the last decade, the area of electroencephalography (EEG) witnessed a progressive move from high-end large measurement devices, relying on accurate construction and providing high sensitivity, to miniature hardware, more specifically wireless wearable EEG devices. While accurate, traditional EEG systems need a complex structure and long periods of application time, unwittingly causing discomfort and distress on the users. Given their size and price, aside from their lower sensitivity and narrower spectrum band(s), wearable EEG devices may be used regularly by individuals for continuous collection of user data from non-medical environments. This allows their usage for diverse, nontraditional, non-medical applications, including cognition, BCI, education, and gaming. Given the reduced need for standardization or accuracy, the area remains a rather incipient one, mostly driven by the emergence of new devices that represent the critical link of the innovation chain. In this context, the aim of this study is to provide a holistic assessment of the consumer-grade EEG devices for cognition, BCI, education, and gaming, based on the existing products, the success of their underlying technologies, as benchmarked by the undertaken studies, and their integration with current applications across the four areas. Beyond establishing a reference point, this review also provides the critical and necessary systematic guidance for non-medical EEG research and development efforts at the start of their investigation.


Author(s):  
Emmanuel U. Ogbodo ◽  
David G. Dorrell ◽  
Adnan M. Abu-Mahfouz

Background: A cognitive radio sensor network (CRSN)-based Smart Grid (SG) is a new paradigm for a modern SG. It is totally different from the traditional power grid and conventional SG. Currently, an SG uses a static resource allocation technique to allocate resources to sensor nodes in the SG network. Static resource allocation is not efficient due to the heterogeneous nature of CRSN-based SGs. Hence, an appropriate mechanism such as dynamic radio resource allocation (RRA) is required for efficient resource allocation in CRSNs for SGs. Objective: The objective of this paper is to investigate and propose suitable dynamic RRA for efficient resource allocation in CRSNs-based SGs. This involves a proposal for appropriate strategy that will address poor throughput and excessive errors in resource allocation. Methods: In this paper, the dynamic RRA approach is used to allocate resources such as frequency, energy, channels and spectrum to the sensor nodes. This is because of the heterogeneity in a CRSN which differs for SG applications. The dynamic RRA approach is based on optimization of resource allocation criteria such as energy efficiency, throughput maximization, QoS guarantee, etc. The methods include an introduced model called “guaranteed network connectivity channel allocation for throughput maximization” (GNC-TM). Also used, is an optimal spectrum-band determination in RRA for improved throughput. Results: The results show that the model outperforms the existing protocol of channel allocation in terms of throughput and error probability. Conclusion: This study explores RRA schemes for CRSNs for SGs. The paper proposed a GNC-TM model, including demonstration of suitable spectrum band operation in CRSNs for SGs.


2020 ◽  
Vol 180 ◽  
pp. 107387 ◽  
Author(s):  
R Rajaguru ◽  
K. Vimala Devi ◽  
P Marichamy

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