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Journal articles on the topic 'Α-β filter'

Author: Grafiati

Published: 4 June 2025

Last updated: 15 July 2025

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Shibata, Takanori, та Kenshi Saho. "Correct Stability Condition and Fundamental Performance Analysis of the α-β-γ-δ Filter". Applied Sciences 8, № 12 (2018): 2523. http://dx.doi.org/10.3390/app8122523.

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This paper theoretically analyzes the fundamental performance of a fourth-order steady-state moving object tracking filter, called an α - β - γ - δ filter. The α - β - γ - δ filter considers estimations of jerk (time-derivative of acceleration) in the motion of targets. First, regarding the stability conditions of the α - β - γ - δ filter, we prove that there are unstable cases even when the conventionally derived stability conditions are satisfied, and then we derive the correct stability conditions. Next, we analytically derive performance indices that indicate the steady-state errors for targets with typical motions. Based on the derived indices, the optimal performance of the α - β - γ - δ filter is theoretically analyzed and compared with that of the traditional second- and third-order steady-state tracking filters, i.e., α - β and α - β - γ filters. Numerical analyses and simulations are used to verify the advantages and disadvantages of the α - β - γ - δ filter over the above-mentioned filters. The practicality of the use of jerk for the tracking filtering problem is revealed in this paper.

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Bandaru, Ravikumar, Jeong Gi Kang, Amal S. Alali та Young Bae Jun. "Γ α , β -BE-Algebras". Journal of Mathematics 2023 (24 лютого 2023): 1–10. http://dx.doi.org/10.1155/2023/4270107.

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The concept of Γ α , β -BE-algebra is introduced as a generalization of a Γ α -BE-algebra and a Γ β -BE-algebra and its properties are studied. We introduced the concepts of α , β -subalgebra and α , β -filter of a Γ α , β -BE-algebra and discussed the relation between these two concepts. We provided conditions for an α , β -subalgebra to be an α , β -filter. We provided equivalent conditions for the formation of an α , β -filter from a nonempty subset of a Γ α , β -BE-algebra. We introduced the concept of α , β -atomic Γ α , β -BE-algebra and studied its properties. We introduced the concept of atomic α , β -filter a Γ α , β -BE-algebra and gave the necessary and sufficient condition for an α , β -filter to be atomic.

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Yang, Dong He. "Face Tracking Based on Particle Filtering and α-β-γ Filtering". Applied Mechanics and Materials 651-653 (вересень 2014): 2306–9. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.2306.

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In view of the traditional particle filter algorithm cannot guarantee effective tracking in the case of target rotation or obscured. The study proposes a tracking method based on α-β-γ filter and particle filter. The algorithm uses α-β-γ filtering prediction position as the next frame image target candidate model of computing center of particle filter algorithm. The algorithm uses α-β-γ filtering prediction position as the next frame image target candidate model of computing center of particle filter. To reduce the number of iterations of particle filter algorithm, strengthen the real-time tracking of moving face. When detect the face is obscured, with α-β-γ filter prediction point as facial movement position, so as to realize the continuity of the movement. The experimental results show that the proposed algorithm improves the traditional particle filter for real-time face tracking, enhancing the ability of anti-occlusion.

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Khan, Junaid, та Kyungsup Kim. "A Performance Evaluation of the Alpha-Beta (α-β) Filter Algorithm with Different Learning Models: DBN, DELM, and SVM". Applied Sciences 12, № 19 (2022): 9429. http://dx.doi.org/10.3390/app12199429.

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In this paper, we present a new Multiple learning to prediction algorithm model that used three different combinations of machine-learning methods to improve the accuracy of the α-β filter algorithm. The parameters of α and β were tuned in dynamic conditions instead of static conditions. The proposed system was designed to use the deep belief network (DBN), the deep extreme learning machine (DELM), and the SVM as three different learning algorithms. Then these learned parameters were trained by the machine-learning algorithms tuned to the α-β filter algorithm as a prediction module, and they gave the final predicted results. The MAE and RMSE were used to evaluate the performance of the proposed α-β filter with different learning algorithms. Each algorithm recorded different best-case accuracy results; for the DBN, we achieved 3.60 and 2.61; for the DELM, we obtained the best-case result of 3.90 and 2.81; and finally, for the SVM, 4.0 and 3.21 were attained in terms of the RMSE and MAE, respectively, as compared to 5.21 and 3.95. When assessed in comparison with the typical alpha–beta filter algorithm, the proposed system provided results with better accuracy.

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Matet, P. "Partitions and filters." Journal of Symbolic Logic 51, no. 1 (1986): 12–21. http://dx.doi.org/10.2307/2273937.

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In [2], Carlson and Simpson proved a dualized version of Ramsey's theorem obtained by coloring partitions of ω instead of subsets of ω. It was at the suggestion of Simpson that the author undertook to study the notion dual to that of a Ramsey ultrafilter. After stating the basic terminology and notation used in the paper in §1, in §2 we establish some basic properties of the lattice of all partitions of a cardinal κ. §3 is devoted to the study of families of pairwise disjoint partitions of ω. §4 is concerned with descending sequences of partitions. In §5, we give some examples of filters of partitions. Properties of such filters are discussed in §6. Co-Ramsey filters are introduced in §7, and it is shown how they can be associated with Ramsey ultrafilters. The main result of §8 is Proposition 8.1, which asserts the existence of a co-Ramsey filter under the continuum hypothesis.We use standard set theoretic conventions and notation. Let κ be a cardinal. We set κ* = κ − {0}. For every ordinal α ≤ κ, (κ)α denotes the set of those sequences X(ν), ν < α, of pairwise disjoint nonempty subsets of κ such that ⋃ν<αX(ν) = κ, and ⋂X(ν) < ⋂X(ν′) whenever ν < ν′. We also let (κ)≤α = ⋃β≤α(κ)β and (κ)<α = ⋃β<α(κ)β. Given X ∈ (κ)α, we put xν = ⋂X(ν) for every ν < α, and we denote by Ax the set of all xν, 0 < ν < α.

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Ding, Yong, Yuan Lu, Ke Yun, Jin’e Liu, and Nan Liang. "The Study on Porosity Controllable Filter Material for the Integrated Gasification Combined Cycle." Solid State Phenomena 315 (March 2021): 10–15. http://dx.doi.org/10.4028/www.scientific.net/ssp.315.10.

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The porous ceramic filter material is the most effective filter materials in the integrated gasification combined cycle. The porous silicon nitride due to its higher mechanical strength, as well as good corrosion resistance, is considered as a promising material in the integrated gasification combined cycle, and it were prepared directly though the SiO2 and α-Si3N4 through carbothermal reduction - pressureless sintering in nitrogen. There was a great lot weight loss in this reaction, so it was expected to create the high porosity materials. The rod-like β-Si3N4 grains and uniform pores were formed through changing the content of α-Si3N4, SiO2 and C. So high-performance and porosity controlled porous silicon nitride filter material was obtained. With an increasing in the α-Si3N4 content, the weight loss, the linear shrinkage, and the porosity decreased, the flexural strength increased accordingly. The porous silicon nitride filter material with addition of 50wt% α-Si3N4 showed a higher aspect ratio β-Si3N4 grains and better mechanical properties .

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COMEDANG, TADA, та PATTNA INTANI. "A ± 0.2 V, 0.12 μW CCTA USING VTMOS AND AN APPLICATION FRACTIONAL-ORDER UNIVERSAL FILTER". Journal of Circuits, Systems and Computers 23, № 09 (2014): 1450126. http://dx.doi.org/10.1142/s0218126614501266.

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In this paper, a variable threshold voltage metal oxide semiconductor (VTMOS) field effect transistor is used to improve an ultra-low voltage, ultra-low power current conveyor transconductance amplifier (CCTA). To achieve the desired result, an analytical subthreshold VTMOS model is used. Designs that utilize the TSMC 0.18 μm technology are verified using PSPICE simulation. The power consumption is simply 0.12 μW at a ± 0.2 V supply voltage. The proposed CCTA is synthesized using fractional-order (FO) universal filters that can simultaneously realise low pass (LP), high pass (HP) and bandpass (BP) responses with independent control of quality factor and pole frequency by transconductances (gm). Moreover, the circuit has low input and high output impedance which would be an ideal choice for cascading in current-mode circuit. The FO filters are constructed using two FO capacitors of orders α and β (0 < α, β ≤ 1). The FO filters provide improved performance in terms of pole frequency compared with conventional-order filters. The filter has a low power consumption of 0.71 μW at a ± 0.2 V supply voltage. The validity of the proposed filter is verified through PSPICE simulations.

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Ikenoue, Masato, Shunshoku Kanae, Zi-Jiang Yang та Kiyoshi Wada. "On Bias-Compensated Least-Squares Methods Using α-filter and β-filter". Proceedings of the ISCIE International Symposium on Stochastic Systems Theory and its Applications 2005 (5 травня 2005): 114–19. http://dx.doi.org/10.5687/sss.2005.114.

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Kim, Jung-Beom, and Sang-Won Choi. "On the Design of Kalman Filter with Low Complexity for 6G-Based ISAC: Alpha and Alpha–Beta Filter Perspectives." Electronics 14, no. 10 (2025): 1938. https://doi.org/10.3390/electronics14101938.

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This study addresses the performance degradation of α and α-β filters in 6G Integrated Sensing and Communications (ISAC) scenarios, attributed to violations of linearity and steady-state assumptions. These filters are originally designed with time-invariant gains derived under such assumptions to ensure low computational complexity. However, deviations from ideal conditions—such as non-white, biased, or non-Gaussian process noise—necessitate corrective mechanisms. We propose a weighted process noise approach that accounts for increased uncertainty due to assumption violations while preserving the filters’ closed-form structure and computational efficiency. By integrating uncertainty into the conventional gain formulation, the proposed method achieves performance closer to the optimal filter. Numerical results demonstrate superior accuracy over conventional filters across various noise variances and scenarios, without requiring parameter tuning. Notably, performance improvements become more pronounced as the measurement interval decreases.

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Hong, Zheng, Jing Qian, Di-Yi Chen та H. C. Iu Herbert. "Fractional-order L β C α filter circuit network". Chinese Physics B 24, № 8 (2015): 080204. http://dx.doi.org/10.1088/1674-1056/24/8/080204.

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Yoo, Jae-Chern, та Young-Soo Kim. "Alpha–beta-tracking index (α–β–Λ) tracking filter". Signal Processing 83, № 1 (2003): 169–80. http://dx.doi.org/10.1016/s0165-1684(02)00388-2.

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Zhao, Xinlin, Song Wang, and Jifeng Liu. "Searching for Accreting Compact Binary Systems from Spectroscopy and Photometry: Application to LAMOST Spectra." Astrophysical Journal 984, no. 1 (2025): 9. https://doi.org/10.3847/1538-4357/adc1b9.

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Abstract Compact objects undergoing mass transfer exhibit significant (and double-peaked) H α emission lines. Recently, new methods have been developed to identify black hole X-ray binaries and calculate their systematic parameters using H α line parameters, such as the full width at half-maximum (FWHM), equivalent width (EW), and separation of double peaks. In addition, the FWHM–EW plane from spectroscopy and the H α color–color diagram from photometry can be used for rapid stellar classification. We measure the H α and H β profiles (e.g., FWHM and EW) using the LAMOST DR9 low- and medium-resolution spectra, and calculate the systematic parameters (e.g., velocity semiamplitude of the donor star, mass ratio, inclination angle, and mass of the accretor). A new correlation between FWHM and K 2, K 2 = 0.205(18) FWHM, is obtained for cataclysmic variables (CVs) in our sample. Both the FWHM–EW plane and the H α color–color diagram can distinguish CVs with FWHM ≳ 1000 km s−1 from Be stars and young stellar objects to some extent. To improve classification accuracy and enhance the selection of compact objects, we propose a new set of idealized filters with effective widths of 30, 130, and 400 Å for the narrow H α filter, broad H α filter, and r-band filter, respectively.

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Narayan, Sunil, Utkal Mehta, Rıta Iro, Hılda Sıkwa'ae, Kajal Kothari, and Nikhil Singh. "Realization of fractional band pass filter on reconfigurable analog device." International Review of Applied Sciences and Engineering 13, no. 1 (2021): 63–69. http://dx.doi.org/10.1556/1848.2021.00308.

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Abstract This paper presents a realization of fractional-order Band pass-filter (FOBF) based on the concepts of fractional order inductors and fractional order capacitors. The FOBF is designed and implemented using both simulation and hardware approaches. The proposed filter order is considered up to second order or less with any real positive number. One of the cases is considered when α ≤ 1 and β ≥ 1. In the second case, the filter is designed when β ≤ 1 and α ≥ 1. In order to calculate the optimal filter parameters, the modified Particle Swarm Optimization (mPSO) algorithm has been utilized for coefficient tuning. Also, a generalized approach to design any second order FOBF is discussed in this work. The realization and performance assessment have been carried out in simulation environment as well as in lab experiment with field programmable analog array (FPAA) development board. The experimental results indicate the value of efforts to realize the fractional filter.

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Wu, Chun-Mu, Paul P. Lin, Zhen-Yu Han та Shu-Rong Li. "Simulation-based optimal design of α-β-γ-δ filter". International Journal of Automation and Computing 7, № 2 (2010): 247–53. http://dx.doi.org/10.1007/s11633-010-0247-8.

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Khan, Junaid, Umar Zaman, Eunkyu Lee, et al. "Optimizing prediction accuracy in dynamic systems through neural network integration with Kalman and alpha-beta filters." PLOS ONE 19, no. 10 (2024): e0311734. http://dx.doi.org/10.1371/journal.pone.0311734.

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In the realm of dynamic system analysis, the Kalman filter and the alpha-beta filter are widely recognized for their tracking and prediction capabilities. However, their performance is often limited by static parameters that cannot adapt to changing conditions. Addressing this limitation, this paper introduces innovative neural network-based prediction models that enhance the adaptability and accuracy of these conventional filters. Our approach involves the integration of neural networks within the filtering algorithms, enabling the dynamic augmentation of parameters in response to performance feedback. We present two modified filters: a neural network-based Kalman filter and an alpha-beta filter, each augmented to incorporate neural network-driven parameter tuning. The alpha-beta filter is enhanced with neural network outputs for its α and β parameters, while the Kalman filter employs a neural network to optimize its internal parameter R and noise factor F. We assess these advanced models using the root mean square error (RMSE) metric, where our neural network-based alpha-beta filter demonstrates a significant 38.2% improvement in prediction accuracy, and the neural network-based Kalman filter achieves a 53.4% enhancement. Hence, our novel approach of integrating neural networks into filtering algorithms stands out as an effective strategy to significantly enhance their performance in dynamic environments.

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Mao, Jingjing, and Zhihui Wu. "A Denoising Scheme for Scanned Wood Grain Images via Adaptive Color Substitution." Forests 14, no. 9 (2023): 1803. http://dx.doi.org/10.3390/f14091803.

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Real-world image denoising is a challenging problem in low-level vision. In order to reduce the luminance noise on scanned wood grain images randomly generated by the Microtek Phantom 9900XL scanner, the images were classified and sorted according to the noise size. The proposed denoising scheme reduces noise by substituting dissimilar pixels within a certain window size. The No.1 to No. 6 wood images with noise size of approximately (or no greater than) 3 pixels × 3 pixels were processed using coarse denoising with a 7 × 7 window (α = 100, β = 30), fine denoising with a 5 × 5 window (α = 90, β = 40), and the Dust & Scratches filter at settings of 1 (pixels) and 35 (levels). The No.7 to No. 16 wood images with noise size of approximately (or no greater than) 1 pixel × 1 pixel were processed using fine denoising with a 5 × 5 window (α = 100, β = 30), and the Dust & Scratches filter at settings of 1 (pixel) and 35 (levels). The proposed Scheme I and II was then compared with Wiener filtering, Gaussian filtering, median filtering, and the Dust & Scratches filter under designated settings. The results of subjective and objective evaluations demonstrated that the proposed Scheme outperformed the above denoising methods on reducing the luminance noise. When using the median values of R (red), G (green), and B (blue) channels within a certain window to substitute the R, G, and B values of the luminance noise, the denoising ranges of α≥100 and β≤30 were suitable for the No.1 to No.16 wood images.

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Saleem, Mohamed Muftah. "New Method to Harmonic Isolation Based on High Selectivity Filter to Control of Shunt Active Filter with Experimental Validation Using DSPACE System." Applied Mechanics and Materials 666 (October 2014): 53–58. http://dx.doi.org/10.4028/www.scientific.net/amm.666.53.

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This paper presents a new control method of a parallel active power filters based on improved harmonic isolation with hardware implementation. The harmonic isolator is based on High Selectivity Filters (it can be tuned at any frequency) and the current control technique consists in a modulated hysteresis current controller. This active filter is intended for harmonic compensation of a diode rectifier feeding a RL load. The study of the active filter control is divided in two parts. The first part deals with the harmonic isolator which generates the harmonic reference currents and is implemented into a DSPACE DS1104 prototyping card. The second part focuses on the generation of the switching pattern of the IGBTs of the inverter by the modulated hysteresis current controller, implemented into an analogue card. The use of High Selectivity Filters instead of classical extraction filters allows extracting directly the voltage and current fundamental components in the α-β axis at high performances. The effectiveness of the new proposed method is verified by computer simulation and by experimental study.

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Kim, Yeo-Won, So-Jeong Lee, Tae-Yeong Jin, Jeong-Yoon Choi, SungHo Lee та Byeong-Gyun Jeon. "Study on Application Possibility of β-glucose from Plant Cellulose for Cellular Energy Source". Korean Science Education Society for the Gifted 14, № 2 (2022): 100–113. http://dx.doi.org/10.29306/jseg.2022.14.2.100.

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The present study investigated the application possibility of β-glucose derived from plant cellulose for a cellular energy source. The β-glucose was firstly extracted by the cellulase treatment from filter paper. The A549, AGS and HCT-116 cancer cell lines was properly proliferated in the DMEM containing 2% serum and 4.5 g/L glucose. Following cancer (A549, AGS and HCT-116), and normal (MRC-5 and DSC) cells treatment in the β-glucose DMEM media, the rate of glucose uptake and cell growth was similar to that of the α-glucose DMEM media, implying that the β-glucose could be used for cellular energy source. Moreover, the differentiation capacity of cancer cells (A549, AGS and HCT-116) into adipocytes in the β-glucose DMEM media was also similar to that of the α-glucose DMEM media, implying that the β-glucose could be also used for energy storage source. Taken together, we concluded that β-glucose derived from plant cellulose could be used as a potential source of cellular energy and storage, like starch α-glucose from starch.

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Laala, Zakaria, Amar Benaissa, Boualaga Rabhi, and Mohamed Fouad Benkhoris. "Neural network controller for five phases shunt active power filter applied for five phase embarked electrical network." International Journal of Power Electronics and Drive Systems (IJPEDS) 14, no. 2 (2023): 1024. http://dx.doi.org/10.11591/ijpeds.v14.i2.pp1024-1032.

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This paper discusses neural network ANN controller applied for five phase shunt active power filter. Three-phase shunt active power filters are widely studied, however in this paper we investigate to extend their application to five phase embarked electrical network. Two-level five phase inverter is used as a shunt active power filter to reduce harmonics and compensate reactive power injected by a five-phase diode rectifier. An artificial neural network controller has been used to regulate the DC side of the inverter, thereby contributing to the calculation of the reference harmonic currents on the one side and controlling the injected harmonic currents on the other. Self-tuning filter (STF) is used to calculate the reference current. By using STF allow to extract the voltage and current fundamental components in the α-β-axis directly without the use of a phase-locked loop (PLL). Simulation results shows that the ANN controller presents appreciable performances in references tracking and the proposed five-phase shunt active power filter provides a sinusoidal supply current in phase with the line voltage with low harmonic distortion.

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Hathiram, Nenavath, та Kumar Jatoth Ravi. "A New Method for Ball Tracking Based on α-β, Linear Kalman and Extended Kalman Filters Via Bubble Sort Algorithm". Indonesian Journal of Electrical Engineering and Computer Science 10, № 3 (2018): 989–99. https://doi.org/10.11591/ijeecs.v10.i3.pp989-999.

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Object tracking is one of the challenging issues in computer vision and video processing, which has several potential applications. In this paper, initially, a moving object is selected by frame differencing method and extracted the object by segment thresholding. The bubble sort algorithm (BSA) arranges the regions (large to small) to make sure that there is at least one big region (object) in object detection process. To track the object, a motion model is constructed to set the system models of Alpha-Beta (α-β) filter, Linear Kalman filter (LKF) and Extended Kalman filter (EKF). Many experiments have been conducted on balls with different sizes in image sequences and compared their tracking performance in normal light and bad light conditions. The parameters obtained are the root mean square error (RMSE), absolute error (AE), object tracking error (OTE), Tracking detection rate (TDR), and peak signal-to-noise ratio (PSNR) and they are compared to find the algorithm that performs the best for two conditions.

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Shin, Sang-Jin, та Wan-Gyu Kim. "A Study for Assessment of Track Accuracy of Phased Array Radar Associated with α-β Filter". Journal of Korean Institute of Electromagnetic Engineering and Science 26, № 9 (2015): 828–36. http://dx.doi.org/10.5515/kjkiees.2015.26.9.828.

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Vo-Dinh, Tuan, and Ala Alak. "Enhanced Room-Temperature Phosphorescence of Anthracene on Cyclodextrin-Treated Filter Paper." Applied Spectroscopy 41, no. 6 (1987): 963–66. http://dx.doi.org/10.1366/0003702874447752.

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This study investigates the enhancement of room-temperature phosphorescence (RTP) for anthracene when the compound is adsorbed on cyclodextrin (CD)-treated filter paper. The results show that β-CD treatment induces a significant increase in anthracene RTP emission, which is normally extremely weak. The α-CD does not produce any strong RTP enhancement, while γ-CD produces relatively lower enhancement than does β-CD. The CD treatment procedure is very simple and improves the analytical usefulness of the RTP method. The binding constants of anthracene to cyclodextrin were measured with the use of thin-layer chromatographic retention values. Anthracene has a higher binding constant with β-CD than with γ-CD, in agreement with the RTP enhancement results.

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Wu, Chun-Mu, Ching-Kao Chang та Tung-Te Chu. "A new EP-based α–β–γ–δ filter for target tracking". Mathematics and Computers in Simulation 81, № 9 (2011): 1785–94. http://dx.doi.org/10.1016/j.matcom.2011.02.002.

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Kellenberger, Stephan, Nicole Hoffmann-Pochon, Ivan Gautschi, Estelle Schneeberger, and Laurent Schild. "On the Molecular Basis of Ion Permeation in the Epithelial Na+ Channel." Journal of General Physiology 114, no. 1 (1999): 13–30. http://dx.doi.org/10.1085/jgp.114.1.13.

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The epithelial Na+ channel (ENaC) is highly selective for Na+ and Li+ over K+ and is blocked by the diuretic amiloride. ENaC is a heterotetramer made of two α, one β, and one γ homologous subunits, each subunit comprising two transmembrane segments. Amino acid residues involved in binding of the pore blocker amiloride are located in the pre-M2 segment of β and γ subunits, which precedes the second putative transmembrane α helix (M2). A residue in the α subunit (αS589) at the NH2 terminus of M2 is critical for the molecular sieving properties of ENaC. ENaC is more permeable to Li+ than Na+ ions. The concentration of half-maximal unitary conductance is 38 mM for Na+ and 118 mM for Li+, a kinetic property that can account for the differences in Li+ and Na+ permeability. We show here that mutation of amino acid residues at homologous positions in the pre-M2 segment of α, β, and γ subunits (αG587, βG529, γS541) decreases the Li+/Na+ selectivity by changing the apparent channel affinity for Li+ and Na+. Fitting single-channel data of the Li+ permeation to a discrete-state model including three barriers and two binding sites revealed that these mutations increased the energy needed for the translocation of Li+ from an outer ion binding site through the selectivity filter. Mutation of βG529 to Ser, Cys, or Asp made ENaC partially permeable to K+ and larger ions, similar to the previously reported αS589 mutations. We conclude that the residues αG587 to αS589 and homologous residues in the β and γ subunits form the selectivity filter, which tightly accommodates Na+ and Li+ ions and excludes larger ions like K+.

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Sanandiya, Naresh D., Kamalesh Prasad, Ramavatar Meena, and Arup K. Siddhanta. "Cellulose of Salicornia brachiata." Natural Product Communications 5, no. 4 (2010): 1934578X1000500. http://dx.doi.org/10.1177/1934578x1000500421.

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Cellulose was extracted from the roots, stems and stem tips of Salicornia brachiata Roxb. Each crude cellulose sample obtained was fractionated into α- and β-celluloses. The yields of crude cellulose from the stems and stem tips were greatest and lowest, respectively, while the yields of α- and β-celluloses were in the order, roots > stems > stem tips. The cellulose samples were characterized by Fourier transform infrared spectroscopy (FTIR), solid state cross polarisation magic angle spinning carbon-13 nuclear magnetic resonance spectroscopy (CP/MAS 13C NMR), X-ray diffraction pattern (XRD), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). The data were compared with those of the celluloses (predominantly α-cellulose) isolated from Whatman filter paper No. 4 (WFP).

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Abreu, José Alano Peres de, Roberto Célio Limão de Oliveira та João Viana da Fonseca Neto. "Rocket tracking impact point prediction using α-β, standard Kalman, extended, Kalman, and unscented Kalman filters: a comparative analysis". Research, Society and Development 9, № 3 (2020): e42932022. http://dx.doi.org/10.33448/rsd-v9i3.2022.

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Accurate information about the impact point (IP) of a suborbital rocket on Earth’s surface during a launch is an important requirement for range safety operations. Four different estimators, i.e., the α-β filter, standard Kalman filter (SKF), extended Kalman filter (EKF), and unscented Kalman filter (UKF), are considered for the suborbital rocket tracking problem, whose data are used specifically for improving the accuracy of the IP prediction (IPP) of these vehicles. This paper presents a comparative analysis between the results of the estimators. Rocket flight data are discussed to demonstrate the advantages and disadvantages of the estimators and to determine the inherent limitations in predicting the aerodynamic effects found in certain flight situations. We discuss the appropriate mathematical model of a filter capable of running the real-time algorithm for the estimation of target position and velocity. This work uses actual data from a radar sensor to evaluate the tracking algorithms. We insert the filter result into the mathematical model developed to predict the rocket IP on Earth's surface. The main goal of this study is to evaluate the performance of four different estimators when specifically applied for the improvement of the IPP of suborbital rockets. It is demonstrated that the UKF outperforms all other tracking algorithms in terms of the accuracy and robustness of IP estimation.

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Bhat, M. K. "Potential application of cellulase and hemicellulase assay techniques for assessing the forage quality and performance of rumen micro-organisms." BSAP Occasional Publication 22 (1998): 290–93. http://dx.doi.org/10.1017/s0263967x00032900.

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Cellulose and hemicellulose are the major structural polysaccharides of plant cell wall. The efficient utilization of these polysaccharides by ruminants is often restricted by the presence of lignin. Cellulose and hemicellulose are hydrolysed by a group of enzymes called cellulases and hemicellulases. The present paper describes the cellulase and hemicellulase assay methods and their potential applications.Carboxymethyl (CM)-cellulose, Avicel, cellobiose, xylobiose, p-nitrophenyl-p β-D-glucoside (pNPG), p-nitrophenyl-β-D-cellobioside (pNPC), p-nitrophenyl-β-D-xyloside (pNPX) and p-nitrophenyl- α-L-arabinofuranoside (pNPAf) were from Sigma. Birchwood xylan and filter paper are from Carl Roth GmbH and Co., Germany and Whatman International Ltd, UK, respectively. H3P04-Swollen cellulose and 4-O-methyl-α-D-glucuronyl-xylotriose (mGpA-Xyl3) were prepared as described (Wood, 1988; Khandkeet al., 1989a).

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Martelli, Pier Luigi, Piero Fariselli, Gianluca Tasco, and Rita Casadio. "The Prediction of Membrane Protein Structure and Genome Structural Annotation." Comparative and Functional Genomics 4, no. 4 (2003): 406–9. http://dx.doi.org/10.1002/cfg.308.

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New methods, essentially based on hidden Markov models (HMM) and neural networks (NN), can predict the topography of both β-barrel and all-α membrane proteins with high accuracy and a low rate of false positives and false negatives. These methods have been integrated in a suite of programs to filter proteomes of Gram-negative bacteria, searching for new membrane proteins.

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KOSUGE, Yoshio, and Masayoshi ITO. "Stability of an ^|^alpha;-^|^beta;-^|^gamma; Filter and Optimal Gains." Transactions of the Society of Instrument and Control Engineers 38, no. 4 (2002): 361–68. http://dx.doi.org/10.9746/sicetr1965.38.361.

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Faiza, Aouiouat A., Sebaa Morsli, and Allaoui Tayeb. "Self Tuning Filter Based Fuzzy Logic Controller for Active Power Filter." Journal Européen des Systèmes Automatisés 53, no. 5 (2020): 739–45. http://dx.doi.org/10.18280/jesa.530517.

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The performance of the Active Power Filter (APF) depends on the identification strategy of the reference currents and their control. Among the control strategies proposed in the literature to identifying the reference currents, that based on Self Tuning Filter (STF) which allows extracting directly the voltage and current fundamental components in the α-β axis at high performances, without any Phase Locked Loop (PLL). The performance of STF is function of its proportional parameter. However, there is no technique existed in the literature to dimensioning the proportional parameter of the STF filter. This paper presents an improved method for identifying the reference harmonic currents to be generated by the APF, based on STF for the extraction of harmonic currents and equipped with a Fuzzy Logic Corrector (FLC) in order to improve the waveform of the electric lines currents. The FLC adjust in real time the proportional parameter of the STF filter. The proposed FLC-STF regulator allows to having an optimal extraction of the harmonic currents. The conventional hysteresis method was used for the current control technique to generate the switching sequences of the static switches of the APF voltage inverter. The obtained simulation results, performed under the MATLAB/Simulink® environment on a system feeding a non-linear load, show good performance.

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Nenavath, Hathiram, та Ravi Kumar Jatoth. "A New Method for Ball Tracking Based on α-β, Linear Kalman and Extended Kalman Filters Via Bubble Sort Algorithm". Indonesian Journal of Electrical Engineering and Computer Science 10, № 3 (2018): 989. http://dx.doi.org/10.11591/ijeecs.v10.i3.pp989-999.

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Uyar, Tamer, Rasmus Havelund, Jale Hacaloglu, Flemming Besenbacher та Peter Kingshott. "Functional Electrospun Polystyrene Nanofibers Incorporating α-, β-, and γ-Cyclodextrins: Comparison of Molecular Filter Performance". ACS Nano 4, № 9 (2010): 5121–30. http://dx.doi.org/10.1021/nn100954z.

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Liu, Man, Choong-Min Kang, J. Mikhail Wolfson та ін. "Measurements of Gross α- and β-Activities of Archived PM2.5 and PM10 Teflon Filter Samples". Environmental Science & Technology 54, № 19 (2020): 11780–88. http://dx.doi.org/10.1021/acs.est.0c02284.

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Azurdia-Meza, Cesar A., Kyujin Lee та Kyesan Lee. "PAPR Reduction in Single Carrier FDMA Uplink by Pulse Shaping Using a β-α Filter". Wireless Personal Communications 71, № 1 (2012): 23–44. http://dx.doi.org/10.1007/s11277-012-0794-0.

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Peicheng, Shi, Wang Chen, Zhang Rongyun, and Wang Suo. "Research on sensorless control method of permanent magnet synchronous motor based on iterated cubature Kalman filter." Science Progress 103, no. 1 (2019): 003685041989027. http://dx.doi.org/10.1177/0036850419890272.

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Aiming at the problems of high cost, increased volume, low reliability, and environmental interference caused by sensor installation on permanent magnet synchronous motor, estimation method for motor speed and rotor position is proposed based on iterated cubature Kalman filter algorithm and applied to permanent magnet synchronous motor sensorless control. First, discrete mathematical model of permanent magnet synchronous motor in α-β coordinate system is established. Then, based on cubature Kalman filter and iterated cubature Kalman filter, simulation model of sensorless vector control system with dual closed-loop of permanent magnet synchronous motor speed and current is established. Also, simulation verification of two working conditions with given rotation speed and load is carried out. Finally, hardware experimental verification platform is built based on TMS320F28335 chip. Both simulation analysis and experimental results show that iterated cubature Kalman filter application to sensorless control of permanent magnet synchronous motor demonstrates good anti-load variation interference, stable motor operation, high motor speed and rotor position estimation accuracy, which suits the application with high requirement for precise motor control and mean important reference value and promotion significance.

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Zhou, Chenyang, and Yanxia Shen. "Suppression of Wind Generator Speed Vibration Based on the Internal Model Control with Three Degrees of Freedom." Energies 15, no. 19 (2022): 7445. http://dx.doi.org/10.3390/en15197445.

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When the wind power system is working in the maximum wind energy tracking area, or when its mechanical drivetrain system vibrates and the vibration frequency is relatively high, the system cannot suppress the speed vibration of the generator in the drivetrain system by adjusting the pitch angle. In this paper, a generator speed control system based on the three degrees of freedom internal model control (3-DOF-IMC) is established to control the generator speed. Thus, a scheme of using the feedback filter in the 3-DOF-IMC to suppress generator speed vibration caused by drivetrain shaft elasticity and gear clearance in the drivetrain system is proposed. Firstly, the vibration problem and waveform of the two-mass wind power drivetrain systems are discussed, and the generator’s vector control and speed control systems are analyzed. Secondly, the principle of the 3-DOF-IMC is described, and the influence of the three controllers on the speed tracking performance and anti-interference performance of the generator is discussed. The suppression ability of the feedback filter for different forms of disturbance signals is emphasized. Finally, the feedback filter controls the generator speed and eliminates the influence of drivetrain vibration on the generator speed. To verify the superiority of the proposed method, the vibration suppression effect, tracking performance and anti-interference performance of the proposed method are compared with the engineering design method (EDM) and conventional IMC (1-DOF-IMC) method. When the parameter α/β = 0.66, the generator speed amplitude overshoot of the proposed method is the same as the EDM. When α/β = 1, it is only 4% of the amplitude overshoot of the EDM. In addition, the tracking performance and anti-interference performance of the proposed method can be adjusted independently, and it is better than the EDM and the 1-DOF-IMC method.

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REGELE, HEINRICH M., EDITH FILLIPOVIC, BRIGITTE LANGER, et al. "Glomerular Expression of Dystroglycans Is Reduced in Minimal Change Nephrosis But Not in Focal Segmental Glomerulosclerosis." Journal of the American Society of Nephrology 11, no. 3 (2000): 403–12. http://dx.doi.org/10.1681/asn.v113403.

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Abstract. Extensive flattening of podocyte foot processes and increased permeability of the glomerular capillary filter are the major pathologic features of minimal change nephrosis (MCN) and focal segmental glomerulosclerosis (FSGS). Adhesion proteins anchor and stabilize podocytes on the glomerular basement membrane (GBM), and presumably are involved in the pathogenesis of foot process flattening. Thus far, α3 β1-integrin was localized to basal cell membrane domains. In this report, α- and β-dystroglycan (DG) were detected at precisely the same location by immunoelectron microscopy, and the presence of α- and β-DG chains was confirmed by immunoblotting on isolated human glomeruli. Because the major DG binding partners in the GBM (laminin, agrin, perlecan), and the intracellular dystrophin analogue utrophin are also present in glomeruli, it appears that podocytes adhere to the GBM via DG complexes, similar to muscle fibers in which actin is linked via dystrophin and DG to the extracellular matrix. As with muscle cells, it is therefore plausible that podocytes use precisely actin-guided DG complexes at their “soles” to actively govern the topography of GBM matrix proteins. Expression of the α/β-DG complex was reported to be reduced in muscular dystrophies, and therefore a search for similar pathologic alterations in archival kidney biopsies from patients with MCN (n = 16) and FSGS (n = 8) was conducted by quantitative immunoelectron microscopy. The density of α-DG on the podocyte's soles was significantly reduced to 25% in MCN, whereas it was not different in normal kidneys and FSGS. The expression of β-DG was reduced to >50% in MCN, and was slightly increased in FSGS. Levels of DG expression returned to normal in MCN after steroid treatment (n = 4). Expression of β1-integrin remained at normal levels in all conditions. These findings point to different potentially pathogenic mechanisms of foot process flattening in MCN and FSGS.

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Bentley, J. "Interfacial Segregation and Concentration Profiles by Energy-Filtered Transmission Electron Microscopy: Issues and Guidelines." Microscopy and Microanalysis 4, S2 (1998): 158–59. http://dx.doi.org/10.1017/s1431927600020912.

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Over the several years that imaging energy filters have been available commercially, numerous and wide-ranging applications have demonstrated elemental mapping at resolutions approaching 1 nm. From reviewing applications of energy-filtered transmission electron microscopy (EFTEM) to interfacial segregation and concentration profiles in metals and ceramics, some guidelines and issues may be identified. The work has been performed with a Gatan imaging filter (GIF) interfaced to a Philips CM30 operated at 300 kV with a LaB6 cathode.For quantitative elemental mapping by EFTEM a number of interrelated parameters [field of view, resolution, collection angle (β), slit width (Δ), incident beam divergence (α), illumination uniformity, probe current (i), drift rate, exposure time (T), and local specimen thickness (t)] have always to be properly selected and controlled. For example, the collection angle should be large enough for a strong signal, but not so large that the signal/background (S/B) and chromatic-aberration-limited spatial resolution (δ) are both degraded.

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Mironyuk, I. F., T. R. Tatarchuk, H. V. Vasylyeva, I. P. Yaremiy, and I. M. Mykytyn. "Morphology, phase composition and radiological properties of fly ash obtained from the Burshtyn thermal power plant." Фізика і хімія твердого тіла 19, no. 2 (2019): 171–78. http://dx.doi.org/10.15330/pcss.19.2.171-178.

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The physic-chemical properties of ash extracted from smoke during the combustion of coal at the Burshtyn thermal power plant were investigated. The particles formed in the flame are crystallized glass beads with a size of 0.8–600 μm. It was found that the ash particles are heterogeneous in their chemical composition. The mass content of the ferric oxides can vary from 2.1% to 96.4%, however, despite this, the Al2O3/SiO2 ratio in the glass balls remains constant at a value of 0.47±0.02. Phase analysis confirmed the presence of α-quartz particles (~ 62 wt%), mullite (~ 32 wt%) and α-FeOOH, α-Fe2O3 and Fe3O4 mixtures (totaling 6 wt%). Radiological studies have revealed higher β- and γ-activity of fly ash, selected from the dump, compared with the fly ash from the electro-filter. This is due to the accumulation of 214Pb and 214Bi radionuclides particles formed on the surface of the particles due to due to decay of 222Rn.

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Graham, Emelie L., Cheng Wu, David M. Bell, et al. "Volatility of aerosol particles from NO₃ oxidation of various biogenic organic precursors." Atmospheric Chemistry and Physics 23, no. 13 (2023): 7347–62. http://dx.doi.org/10.5194/acp-23-7347-2023.

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Abstract. Secondary organic aerosol (SOA) is formed through the oxidation of volatile organic compounds (VOCs), which can be of both natural and anthropogenic origin. While the hydroxyl radical (OH) and ozone (O3) are the main atmospheric oxidants during the day, the nitrate radical (NO3) becomes more important during the nighttime. Yet, atmospheric nitrate chemistry has received less attention compared to OH and O3. The Nitrate Aerosol and Volatility Experiment (NArVE) aimed to study the NO3-induced SOA formation and evolution from three biogenic VOCs (BVOCs), namely isoprene, α-pinene, and β-caryophyllene. The volatility of aerosol particles was studied using isothermal evaporation chambers, temperature-dependent evaporation in a volatility tandem differential mobility analyzer (VTDMA), and thermal desorption in a filter inlet for gases and aerosols coupled to a chemical ionization mass spectrometer (FIGAERO-CIMS). Data from these three setups present a cohesive picture of the volatility of the SOA formed in the dark from the three biogenic precursors. Under our experimental conditions, the SOA formed from NO3 + α-pinene was generally more volatile than SOA from α-pinene ozonolysis, while the NO3 oxidation of isoprene produced similar although slightly less volatile SOA than α-pinene under our experimental conditions. β-Caryophyllene reactions with NO3 resulted in the least volatile species. Four different parameterizations for estimating the saturation vapor pressure of the oxidation products were tested for reproducing the observed evaporation in a kinetic modeling framework. Our results show that the SOA from nitrate oxidation of α-pinene or isoprene is dominated by low-volatility organic compounds (LVOCs) and semi-volatile organic compounds (SVOCs), while the corresponding SOA from β-caryophyllene consists primarily of extremely low-volatility organic compounds (ELVOCs) and LVOCs. The parameterizations yielded variable results in terms of reproducing the observed evaporation, and generally the comparisons pointed to a need for re-evaluating the treatment of the nitrate group in such parameterizations. Strategies for improving the predictive power of the volatility parameterizations, particularly in relation to the contribution from the nitrate group, are discussed.

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Ueta, Wataru, Yoshio Ohta, and Mikito Kitayama. "Development of Silicon Nitride Porous Bodies with Micro-Macro Complex Pore Structure for the Application of the ‘Bio-Filter’." Materials Science Forum 750 (March 2013): 332–35. http://dx.doi.org/10.4028/www.scientific.net/msf.750.332.

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In order to develop the ‘Bio-filter’, Si3N4 porous bodies with micro-macro complex pore structure were fabricated. The micro-pores were successfully introduced by inserting PE meshes between the green tapes. Micro-pore size was controlled by adding a small amount of the β-Si3N4 ‘seed’ particles to the α-Si3N4 raw powder. It is expected that the aerobic microbes colonize along the micro-pores consuming dissolved oxygen, which makes the anaerobic ones colonized within the micro-pores to develop the microbe consortium. In this study, this concept was verified by using the S. cerevisiae and B. bifidum as the aerobic and anaerobic microbes, respectively.

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Jaoui, Mohammed, Tadeusz E. Kleindienst, Kenneth S. Docherty, Michael Lewandowski та John H. Offenberg. "Secondary organic aerosol formation from the oxidation of a series of sesquiterpenes: α-cedrene, β-caryophyllene, α-humulene and α-farnesene with O3, OH and NO3 radicals". Environmental Chemistry 10, № 3 (2013): 178. http://dx.doi.org/10.1071/en13025.

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Environmental context Sesquiterpenes, chemicals emitted by terrestrial vegetation, are oxidised in the ambient atmosphere leading to the formation of secondary organic aerosol. Although secondary organic aerosol can have significant effects on air quality from local to global scales, considerable gaps remain in our understanding of their various sources and formation mechanisms. We report studies on the oxidation of sesquiterpenes aimed at improving aerosol parameterisation for these reactions for incorporation into future air quality models. Abstract A series of sesquiterpenes (SQT) were individually oxidised under a range of conditions, including irradiation in the presence of NOx, reactions with O3 or reactions with NO3 radicals. Experiments were conducted in either static mode to observe temporal evolution of reactants and products or in dynamic mode to ensure adequate collection of aerosol at reasonably low reactant concentrations. Although some measurements of gas-phase products have been made, the focus of this work has been particle phase analysis. To identify individual products, filter samples were extracted, derivatised and analysed using gas chromatography mass spectrometry techniques. The results indicate that secondary organic aerosol (SOA) is readily formed from SQT oxidation. The high reactivity of these systems and generally high conversion into SOA products gives rise to high SOA levels. SOA yields (ratio of SOA formed to hydrocarbon reacted) averaged 0.53 for ozonolysis, 0.55 for photooxidation and 1.19 for NO3 reactions. In select experiments, SOA was also analysed for the organic matter/organic carbon (OM/OC) ratio, and the effective enthalpy of vaporisation (ΔHvapeff). The OM/OC ranged from 1.8 for ozonolysis and photooxidation reactions to 1.6 for NO3 reactions, similar to that from SOA generated in monoterpene systems. ΔHvapeff was measured for β-caryophyllene–NOx, β-caryophyllene–O3, β-caryophyllene–NO3, α-humulene–NOx and α-farnesene–NOx systems and found to be 43.9, 41.1, 44.9, 48.2 and 27.7 kJ mol–1. Aerosol yields and products identified in this study are generally in good agreement with results from several studies. A detailed examination of the chamber aerosol for the presence of chemical tracer compounds was undertaken. Only β-caryophyllinic acid, observed mainly under β-caryophyllene photooxidation and ozonolysis experiments, was detected in ambient aerosol. Chemical analysis yielded compounds having oxygen and nitrogen moieties present, which indicates continued evolution of the particles over time and presents high dependence on the SQT–oxidant system studied. This study suggests that SOA from laboratory ozonolysis experiments may adequately represent ambient aerosol in areas with SQT emissions.

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Kosuge, Yoshio, та Masayoshi Ito. "Evaluating an α–β filter in terms of increasing a track update-sampling rate and improving measurement accuracy". Electronics and Communications in Japan (Part I: Communications) 86, № 10 (2003): 10–20. http://dx.doi.org/10.1002/ecja.10113.

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Kosuge, Yoshio. "Optimal gains of an α–β filter derived from a tracking method using a weighted measurement covariance matrix". Electronics and Communications in Japan (Part I: Communications) 89, № 10 (2006): 34–43. http://dx.doi.org/10.1002/ecja.20273.

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Huang, Fang, and Ying Liu. "Study of Interaction between Human Serum Albumin and Miconazole Nitrate Using Multi-Spectroscopic Methods." Advanced Materials Research 955-959 (June 2014): 475–78. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.475.

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The interaction of human serum albumin (HSA) and miconazole nitrate (MIN) had been studied by multi-spectroscopic methods. The inner filter effect was corrected before used the original data. The results indicated that MIN induced the fluorescence quenching of HSA was static quenching procedure. According to the Van’t Hoff equation, the interaction of HSA and MIN was determined by negative enthalpy change and positive entropy change, which showed that electrostatic forces were the major force in the binding process. The displacement experiments revealed that MIN binds in the vicinity of site I of HSA. The binding distance between Trp214 of HSA and MIN was 3.82 nm. Furthermore, the alternations of HSA secondary structure were calculated by FT-IR spectra. Upon formation of HSA-MIN complexes, the amount of α-helix structure reduced from 43.28% to 29.92%, β-sheet reduced from 22.59% to 18.79%, β-turn increased from 20.33% to 30.11% and random increased from 13.80% to 21.19%.

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Beyoro-Amado, Zeleke, Miguel Sánchez-Portal, Ángel Bongiovanni, et al. "GLACE survey: Galaxy activity in ZwCl0024+1652 cluster from strong optical emission lines." Monthly Notices of the Royal Astronomical Society 501, no. 2 (2020): 2430–50. http://dx.doi.org/10.1093/mnras/staa3812.

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ABSTRACT Although ZwCl0024+1652 galaxy cluster at z ∼ 0.4 has been thoroughly analysed, it lacks a comprehensive study of star formation and nuclear activity of its members. With GaLAxy Cluster Evolution (GLACE) survey, a total of 174 H α emission-line galaxies (ELGs) were detected, most of them having [N ii]. We reduced and analysed a set of [O iii] and H β tunable filter (TF) observations within GLACE survey. Using H α priors, we identified [O iii] and H β in 35 (∼20 per cent) and 59 (∼34 per cent) sources, respectively, with 21 of them having both emission lines, and 20 having in addition [N ii]. Applying BPT-NII diagnostic diagram, we classified these ELGs into 40 per cent star-forming (SF), 55 per cent composites, and 5 per cent LINERs. Star formation rate (SFR) measured through extinction corrected H α fluxes increases with stellar mass (M*), attaining its peak at $\mathrm{\mathit{ M}}_{*}\sim 10^{9.8}\, \mathrm{M}_\odot$. We observed that the cluster centre to ∼ 1.3 Mpc is devoid of SF galaxies and AGN. Our results suggest that the star formation efficiency declines as the local density increases in the cluster medium. Moreover, the SF and AGN fractions drop sharply towards high-density environments. We observed a strong decline in SF fraction in high M*, confirming that star formation is highly suppressed in high-mass cluster galaxies. Finally, we determined that SFR correlates with M* while specific SFR (sSFR) anticorrelates with M*, both for cluster and field. This work shows the importance and strength of TF observations when studying ELGs in clusters at higher redshifts. We provide with this paper a catalogue of ELGs with H β and/or [O iii] lines in ZwCl0024+1652 cluster.

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Rizzo, Alessandro, Francesco Cardellini, Claudio Poggi, et al. "Novel Algorithm for Radon Real-Time Measurements with a Pixelated Detector." Sensors 22, no. 2 (2022): 516. http://dx.doi.org/10.3390/s22020516.

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Nowadays, radon gas exposure is considered one of the main health concerns for the population because, by carrying about half the total dose due to environmental radioactivity, it is the second cause of lung cancer after smoking. Due to a relatively long half-life of 3.82 days, the chemical inertia and since its parent Ra-226 is largely diffuse on the earth’s crust and especially in the building materials, radon can diffuse and potentially saturate human habitats, with a concentration that can suddenly change during the 24 h day depending on temperature, pressure, and relative humidity. For such reasons, ‘real-time’ measurements performed by an active detector, possibly of small dimensions and a handy configuration, can play an important role in evaluating the risk and taking the appropriate countermeasures to mitigate it. In this work, a novel algorithm for pattern recognition was developed to exploit the potentialities of silicon active detectors with a pixel matrix structure to measure radon through the α emission, in a simple measurement configuration, where the device is placed directly in air with no holder, no collection filter or electrostatic field to drift the radon progenies towards the detector active area. This particular measurement configuration (dubbed as bare) requires an α/β-discrimination method that is not based on spectroscopic analysis: as the gas surrounds the detector the α particles are emitted at different distances from it, so they lose variable energy amount in air depending on the traveled path-length which implies a variable deposited energy in the active area. The pixels matrix structure allows overcoming this issue because the interaction of α, β and γ particles generate in the active area of the detector clusters (group of pixels where a signal is read) of different shape and energy dispersion. The novel algorithm that exploits such a phenomenon was developed using a pixelated silicon detector of the TimePix family with a compact design. An α (Am-241) and a β (Sr-90) source were used to calibrate the algorithm and to evaluate its performances in terms of β rejection capability and α recognition efficiency. Successively, the detector was exposed to different radon concentrations at the ENEA-INMRI radon facility in ‘bare’ configuration, in order to check the linearity of the device response over a radon concentration range. The results for this technique are presented and discussed, highlighting the potential applications especially the possibility to exploit small and handy detectors to perform radon active measurements in the simplest configuration.

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Schuger, Lucia, Amy P. N. Skubitz, Jun Zhang, Lydia Sorokin та Li He. "Laminin α1 Chain Synthesis in the Mouse Developing Lung: Requirement for Epithelial–Mesenchymal Contact and Possible Role in Bronchial Smooth muscle Development". Journal of Cell Biology 139, № 2 (1997): 553–62. http://dx.doi.org/10.1083/jcb.139.2.553.

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Laminins, the main components of basement membranes, are heterotrimers consisting of α, β, and γ polypeptide chains linked together by disulfide bonds. Laminins-1 and -2 are both composed of β1 and γ1 chains and differ from each other on their α chain, which is α1 and α2 for laminin-1 and -2, respectively. The present study shows that whereas laminins-1 and -2 are synthesized in the mouse developing lung and in epithelial–mesenchymal cocultures derived from it, epithelial and mesenchymal monocultures lose their ability to synthesize the laminin α1 chain. Synthesis of laminin α1 chain however returns upon re-establishment of epithelial–mesenchymal contact. Cell–cell contact is critical, since laminin α1 chain is not detected in monocultures exposed to coculture-conditioned medium or in epithelial–mesenchymal cocultures in which heterotypic cell–cell contact is prevented by an interposing filter. Immunohistochemical studies on cocultures treated with brefeldin A, an inhibitor of protein secretion, indicated both epithelial and mesenchymal cells synthesize laminin α1 chain upon heterotypic cell– cell contact. In a set of functional studies, embryonic lung explants were cultured in the presence of monoclonal antibodies to laminin α1, α2, and β/γ chains. Lung explants exposed to monoclonal antibodies to laminin α1 chain exhibited alterations in peribronchial cell shape and decreased smooth muscle development, as indicated by low levels of smooth muscle α actin and desmin. Taken together, our studies suggest that laminin α1 chain synthesis is regulated by epithelial–mesenchymal interaction and may play a role in airway smooth muscle development.

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Descamps, Lilian R., Carolina Sánchez Chopa, and Adriana A. Ferrero. "Activity of Schinus Areira (Anacardiaceae) Essential Oils against the Grain Storage Pest Tribolium castaneum." Natural Product Communications 6, no. 6 (2011): 1934578X1100600. http://dx.doi.org/10.1177/1934578x1100600632.

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Essential oils extracted from leaves and fruits of Schinus areira (Anacardiaceae) were tested for their repellent, toxic and feeding deterrent properties against Tribolium castaneum (Coleoptera: Tenebrionidae) larvae and adults. A topical application assay was employed for the contact toxicity study and filter paper impregnation for the fumigant assay. A treated diet was also used to evaluate the repellent activity and a flour disk bioassay for the feeding deterrent action and nutritional index alteration. The essential oil of the leaves contained mainly monoterpenoids, with α-phellandrene, 3-carene and camphene predominant, whereas that from the fruits contained mainly α-phellandrene, 3-carene and β-myrcene. The leaf essential oil showed repellent effects, whereas that from the fruit was an attractant. Both oils produced mortality against larvae in topical and fumigant bioassays, but fumigant toxicity was not found against adults. Moreover, both essential oils produced some alterations in nutritional index. These results show that the essential oils from S. areira could be applicable to the management of populations of Tribolium castaneum.

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Zhang, Li Yang, Fang Huang, and Ying Liu. "Characterization of the Interaction between Human Serum Albumin and Minocycline by Spectroscopic Methods." Advanced Materials Research 955-959 (June 2014): 293–96. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.293.

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In this paper, the interaction between human serum album (HSA) and minocycline (MNC) in physiological solution had been studied by fluorescence spectroscopy, UV spectrum and FT-IR spectroscopy. The inner filter effect was corrected. The results indicated that the fluorescence quenching of HSA was primarily due to static quenching, and thermodynamic parameters exhibited hydrogen bond and van der Waals force played the major role in stabilizing HSA-MNC complex. Through site marker competitive experiments had been assigned to possess the high-affinity binding site for MNC in subdomain IIA of HSA. Binding constant was obtained to be 1.64×106L·mol-1(298K) and 1.16×104L·mol-1(310K), the number of binding sites were both 1. The alternations of HSA secondary structure, such as α-helix and β-sheet were quantitatively calculated from FT-IR.

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