Miracle-dz/UniFAR-FTUs huggingface dataset:
An investigation on surface conditions for Si molecular beam epitaxial (MBE) growth

Contamination‐free Si substrate surfaces are vitally important to the subsequent molecular beam epitaxy (MBE) growth. A number of studies on the major contaminants, i.e., C and O, on Si surfaces have been done, and new cleaning procedures for reducing these contaminants have been proposed. However, to date the detailed behavior of C and O on Si surfaces and their effects on the subsequent Si MBE growths are not well established. In the present work, the behavior of the contaminants on heated Si surfaces were investigated using Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). Also, the chemical bonding of C on Si surfaces was studied by analyzing the AES line shapes of carbon and comparing them with those known carbon chemical states. For the chemical cleaning procedures used in this study, a silicon oxide protection layer is grown onto the cleaned Si surface prior to sample loading. The property of this silicon oxide layer is studied using ellipsometry measurements. To verify .
Resurrecting the Value Premium

The prolonged poor performance of the value factor has led to doubts about whether the value premium still exists. Some have noted that the observed returns still fall within statistical confidence intervals, but such arguments do not restore full confidence in the value premium. This article adds to the literature by showing that the academic value factor, HML, has not only suffered setbacks in recent years but has, in fact, been weak for decades already. However, the authors show that the value premium can be resurrected using insights that are well documented in the literature or common knowledge among practitioners. In particular, they include more powerful value metrics, apply some basic risk management, and make more effective use of the breadth of the liquid universe of stocks. Their enhanced value strategy also suffers in recent years, but this is largely explained by an extreme widening of valuation multiples similar to the late 1990s. The authors conclude that a solid value premium is still clearly present in the cross-section of stock returns. TOPICS: Analysis of individual factors/risk premia, developed markets, emerging markets, factor-based models Key Findings ▪ The standard academic value factor has been weak for decades already, but we show that the value premium can be resurrected with a more sophisticated approach. ▪ Our key enhancements are using more powerful value metrics, applying some basic risk management, and making more efficient use of opportunities in liquid stocks. ▪ The enhanced value strategy also suffers in recent years, but this is largely explained by an extreme widening of valuation multiples similar to the late 1990s.
Design of bionic goat quadruped robot mechanism and walking gait planning.

In order to improve the walking stability and obstacle jumping ability of the robot on the slope, the goat was taken as the bionic prototype, a kind of bionic goat quadruped robot has been designed. By the bionic principle, the mechanical structure of the quadruped robot was designed, and the Denavit-Hartenberg (D-H) method was used to build the kinematic model, through which the forward and inverse kinematics of the robot was calculated, thus the equations of velocity and acceleration of the joint angle change were obtained during the quadruped robot motion, providing control theory foundation for robots. During walk gait planning, a low contact compact foot trajectory planning method using a high order polynomial curve was used to carry out the foot trajectory planning of the robot for the swing phase and stance phase. Through MATLAB software simulation, the simulation results of MATLAB software showed that the trajectory of the foot of the quadruped robot was semi-elliptic in a gait cycle, which were basically consistent with the foot trajectory obtained from the previous goat slope walking test. Therefore, the simulation results by MATLAB software showed that the foot trajectory was reasonable. Based on this, a gait plan was carried out, and the sequence of the lift leg steps of the robot was obtained. The test platform for the whole machine was built. The results showed that the height of the leg of the quadruped robot was 7.37 cm, and the length of the gait was 28.40 cm. Compared with the planned average gait length S=30 cm and average step height H=7 cm, the error of the leg height and the gait length was 5.28% and 5.33%, respectively. The designed gait planning achieved the expected results. The knee joint angle varied from 126.3° to 156.1°, and the hip joint angle varied from 103.9° to 138.4°. The changes in the joint angle of the quadruped robot could prove the correctness of the foot motion trajectory planning, which will provide a theoretical basis for the structural design and gait planning of the quadruped robot. Keywords: bionic goat, quadruped robot, mechanism design, gait plan, D-H method, foot trajectory DOI: 10.25165/j.ijabe. 20201305.5769 Citation: Zhang F, Teng S, Wang Y F, Guo Z J, Wang J J, Xu R L. Design of bionic goat quadruped robot mechanism and walking gait planning. Int J Agric & Biol Eng, 2020; 13(5): 32–39.
Dump size and distance from the nest define the investment in waste management in Sericomyrmex mayri (Formicidae: Myrmicinae: Attini)

The farming system practiced by non-leaf-cutting ants Sericomyrmex mayri (Formicidae: Myrmicinae: Attini) involves a mutualistic interaction with symbiotic fungi. Their colonies’ success depends on several factors, such as the fungus garden protection against pathogens. Garden contamination may depend on the aspects involved in waste management. However, specific local conditions, including nest and dump sizes, nest-dump distances and abiotic conditions are relevant and overlooked, especially for non-leaf-cutting ants. We aimed to explore the natural history involved in Sericomyrmex mayri waste management. Hence, we documented the relationships between 1) the foraging rate and waste removal activities with dump size, 2) the size of refuse dumps and their distance from nest entrances, and 3) the foraging activity and the rate of waste disposal with climatic conditions. The study was developed in the Atlantic Forest, Southeastern Brazil, wherein 33 colonies’ activities were monitored for three consecutive days, during different day-periods. More prominent dumps received less waste and were located at further distances from the nest. Additionally, daily temperature and humidity positively influenced waste disposal and foraging activities, respectively. These findings provide information on how dump size and distance from the nest may define the investment of waste management of non-leaf-cutting ants.
Regenerated‐Cellulose/Multiwalled‐ Carbon‐Nanotube Composite Fibers with Enhanced Mechanical Properties Prepared with the Ionic Liquid 1‐Allyl‐3‐methylimidazolium Chloride

Carbon nanotubes (CNTs) have attracted tremendous attention since their discovery because of their unique electronic and mechanical properties. [1] It has been reported that CNTs are extremely strong, with strength of tens of gigapas-cals, and exceptionally stiff, with Young’s modulus in the tera-pascal range, yet remarkably flexible, with a breaking strain larger than 5%. [2] In addition, CNTs have high aspect ratios (> 100). [3] These properties make it of interest to use CNTs as excellent reinforcing agents in polymers. It has been generally recognized that the reinforcing efficiency of CNTs will strongly depend on their dispersion and orientation, as well as on the CNT/matrix interfacial strength. [4] Another critical issue that has been little-considered previously is the impact of the shape of the embedded CNTs on the effective mechanical properties of the nanotube-reinforced polymer. A study by Fisher et al. has demonstrated that inherent CNT curvature significantly reduces its effective reinforcement compared to straight CNTs. [5] The most effective approaches towards increasing the orientation of CNTs within a polymer matrix include stretching and spinning the composites to form films and fibers. [6] Spinning methods used to create composite fibers containing CNTs include melt-spinning, solution-spin-ning, and electrospinning. During the past several years, many kinds of polymers have been used to prepare polymer/CNT composite fibers. These polymers include polypropylene (PP), [6c] polyethylene (PE), [6d] polyacrylonitrile (PAN), [6e] poly(vinylidene fluoride) (PVDF), [6f] poly( p -phenylene ben-zobisoxazole
Protein chemical shifts arising from α-helices and β-sheets depend on solvent exposure

The NMR chemical shifts of certain atomic nuclei in proteins (1Hα,13Cα, and 13Cβ) depend sensitively on whether or not the amino acid residue is part of a secondary structure (α-helix, β-sheet), and if so, whether it is helix or sheet. The physical origin of the different chemical shifts of atomic nuclei in α-helices versus β-sheets is a problem of long standing. We report that the chemical shift contributions arising from secondary structure (secondary structure shifts) depend strongly on the extent of exposure to solvent. This behavior is observed for 1Hα, 13Cα, and 13Cβ (sheet), but not for13Cβ (helix), whose secondary structure shifts are small. When random coil values are subtracted from the chemical shifts of all1Hα nuclei (Pro residues excluded) and the residual chemical shifts are summed to plot the mean values against solvent exposure, the results give a funnel-shaped curve that approaches a small value at full-solvent exposure. When chemical shifts are plotted instead against Elocal, the electrostatic contribution to conformational energy produced by local dipole–dipole interactions, a well characterized dependence of 1Hα chemical shifts on Elocal is found. The slope of this plot varies with both the type of amino acid and the extent of solvent exposure. These results indicate that secondary structure shifts are produced chiefly by the electric field of the protein, which is screened by water dipoles at residues in contact with solvent.
Polycyclic aromatic hydrocarbons in topsoil: emergent trends in environmental assessment

Polycyclic aromatic hydrocarbons (PAHs) are extremely teratogenic, carcinogens and significant environmental pollutants. The conc. of 16 priority PHAs in soils from the urbanized/ industrialized outskirts in the vicinity of Jordan Petroleum Refinery Company were analyzed along with their associations with soil properties, its sources and spatial distribution. The selected soil properties include total organic carbon (% TOC), soil pH and cation exchange capacity. The pH of the soil samples varies from 7.0 to 8.2 with an average of 7.7. The total organic matter ranged from 0.2% to 3.6% with an average of 0.8 %. The CEC ranged from 14.46 to 42.9 cmol [Na+]/ Kg with an average of 28.5 cmol (Na+]/ Kg. PAHs were analyzed by using High Performance Liquid Chromatography having fluorescence detector. Only 11 PAH compounds were detected in almost all samples; anthracene, naphthalene, acenaphthene, anthracene, pyrene, fluorine, benzo[a] and benzo[b] fluoranthene, benzo[k] fluoranthene, benzo[a] perylene, dibenzo [g.h.i] pyrene and dibenzo[a, h] anthracene from the screened EPA 16 priority PAHs. Total PAHs concentration ranged from 32.7 to 573.5 μg /kg with an average of 219.9 μg/kg. Half of the sampling sites in the study area would be considered as uncontaminated with PAHs (<200 µg/kg) while the rest of sampling sites would be considered as weakly polluted (200-600 µg/kg). Factor analysis of PAHs identifies four major potential sources impact the study area; oil refinery emissions, Al-Hussein power plant, anthropogenic sources; industrial boilers; recycling mills, steel smelters and small size workshops and traffic emissions. The PAHs concentrations/ levels were used as the input data for a point-based contouring map, for studying the distribution of PAHs in the study area soil. The geochemical maps which generated provided a confirmation of the results in sources identified by factor analysis for PAHs analyzed.
Silver nanorods used to promote SERS as a quantitative analytical tool

We have fabricated silver nanorod arrays by electrodepositing the nanorods evenly in the shallow pores of porous anodic aluminum oxide (AAO) templates. The diameter and length were 28 and 44 nm, respectively. The maxima of the transverse and longitudinal modes of the surface plasmon were near 417 and 511 nm, respectively. A good surface-enhanced Raman scattering (SERS) spectrum was observed by excitation with the 514.5-nm laser line. The SERS intensity increased almost linearly upon malachite green isothiocyanate adsorption on the tips of the silver nanorods as the concentration of the mother solutions increased. Our results show that silver nanorods fabricated on AAO templates could be used as an SERS substrate for quantitative analyses. Copyright © 2009 John Wiley & Sons, Ltd.
Complete mitochondrial genomes of Karchaev goat (Capra hircus)

Abstract Karachaev goat (Capra hircus) is a local breed from North-Caucasus region, Russia. Here we present complete mitochondrial genome of Karachaev goat from the republic of Karachaevo-Cherkessia, Russia. The length of the studied sequence was 16,624 bp in size. It was shown that the studied specimen belonged to haplogroup A.
The spectrum of silicon hydride

A previously unrecorded band, stretching from about λ 4100 to λ 4200, was observed by Prof. A. Fowler on a photograph of the vacuum-arc spectrum of silicon taken with the first order of a 10-foot grating in 1919, and was con­sidered to be most probably due to silicon hydride. In 1921 Prof. Wood, in the course of his work on the hydrogen spectrum, observed a band of similar appearance, which he also considered to be due to a compound of silicon (from the glass walls of the discharge tube) and hydrogen. He gave a list of the wave-lengths of the band lines, and these agree well with the prominent lines on Prof. Fowler’s plate, although the latter contains many more lines. In the course of the present work it was found that the band observed by Prof. Fowler was in reality a mixture of the spectrum of silicon hydride and that of silicon nitride. The band of Prof. Wood’s plate includes, however, only lines now attributed to the compound SiH. Experimental . The conditions most favourable for the production of the band were first investigated with the aid of a spectrograph of very wide aperture and low dispersion (about 40 A. per millimetre at λ 4100). Photographs of the spectra of the silicon arc in vacuo , in water vapour, in hydrogen at atmospheric pressure and at very low pressure, were taken, but these sources all appear to be much inferior to the arc in hydrogen at pressures between about 3 and 9 cm. of mercury. Using the latter source photographs on a larger scale were then taken with the 10-foot grating spectrograph. Using the first order (5.5 A. per millimetre) a strong plate was obtained with an exposure of about ¼ hour. The current was approximately 6 amperes at 110 volts, and the pressure of hydrogen about 4 cm. of mercury.
The Electronic Role of the TiO2 Light-Scattering Layer in Dye-Sensitized Solar Cells

Dye-sensitized solar cells have been fabricated with different kinds of TiO2 films including SiO2 coated and bare TiO2 microparticles as light-scattering layer (LSL). Results show that the LSL barely affects the cell's dark current, whereas under illumination, it made a significant contribution to the total photocurrent. Photo-voltage decay measurements performed under bias illumination show the density of electronic states (DOS) of the LSL to be two times smaller than that of a transparent nanoparticle layer (TNL). Strikingly, DSCs fabricated from a 4. 5μm thick LSL alone showed a conversion efficiency of 5% despite of being pale pink in color. This impressive performance is attributed to light containment in the LSL and a low density of defect electronic states.
Accuracy comparison between the three-dimensional position of planned and placed implants with flapless fully-guided surgery: 1-year follow-up from a single-cohort retrospective study

Aim This research was performed to evaluate the in vivo accuracy of flapless, computer-guided implant placement by comparing the three-dimensional position of planned and placed implants. Materials and methods In this retrospective study the results from a 1-year follow-up of a single-cohort of 15 patients (30 implants) are reported. A 3D planning software was used to determine the correct placement, considering the bone volume, the functional and the aesthetic prosthetic result. CAD/CAM technology was used to turn the virtual plan into the surgical guide. Results The statistical analysis showed a mean radial deviation of the implant head of 0.3 mm (SD 0.21), a mean radial deviation of the implant apex of 0.58 mm (SD 0.33), a mean depth deviation of the implant head of 0.37 mm (SD 0.29), a mean depth deviation of the implant apex of 0.43 mm (SD 0.25) and a mean angular deviation of the long axis of 2.87° (SD 1.99); the mean actual translation between the planned and the placed implant was 0.66 mm (SD 0.35) at implant platform and 1.04 mm (SD 0.47) at apex. Conclusion Flapless and computer-guided implant placement proved to be a reliable clinical option for an accurate implant insertion.
Characterization of the complete mitochondrial genome of Hyphessobrycon herbertaxelrodi (Characiformes, Characidae) and phylogenetic studies of Characiformes

Abstract In this study, the complete mitochondrial genome of Hyphessobrycon herbertaxelrodi is presented, and we also discussed its mitochondrial characteristics. The full length of the mitochondrial genome was 17,417 bp, including 13 protein coding genes (PCGs), 2 ribosomal RNAs (12S and 16S), 22 transfer RNA genes, 1 non-coding control region (D-loop), and 1 origin of replication on the light-strand. The total nucleotide composition of mitochondrial DNA was 29.76%A, 29.88%T, 25.35%C, 15.01%G, and AT was 59.64%. The phylogenetic tree suggested that H. herbertaxelrodi shared the most recent common ancestor with Astyanax giton, Grundulus bogotensis, Astyanax paranae, and Oligosarcus argenteus.
Designing of Half-Masks of Filtering Respirators

Introduction. Diseases of the respiratory system head the list of occupational diseases. They are caused by pollution of the working zone air with harmful aerodispersed particles, use of improper individual respiratory protective devices. Problem Statement. The efficiency of filtering respirators depends on two components: time of protective effect and insulating properties of half-masks. This requires conducting relevant research in order to design the half-masks which allow providing high insulating properties. Purpose. Improvement of protective effect of filtering respirators by improving their design with respect to anthropometric peculiarities of workers’ faces. Materials and Methods. To develop the surface of a half-mask, the equation of free energy of a bent optional plate was used, which is outlined with a two-dimensional spline-surface, its unknown coefficients are defined by the method of proportional parts based on the data of three dimensional coordinates of the key points of anthropometric facial features. Results. Regularities of forming the surface of half-masks were defined based on the data of three dimensional coordinates of the key points of anthropometric facial features. A method was developed for measuring the temperature of obturator surface with a thermal imagery device based on output signal processing, which allows carrying out on-line control of areas where gaps occur along the obturation line as well as defining deterioration of insulating properties of a dust mask and estimating its protection factor. Conclusion. The algorithm of half-mask design was developed with respect to the results of 3D scanning of faces, digital models of head developing as well as half-masks surface and obturator construction associated with them. The reasonable parameters of filtering box, size of ioutlet for providing the minimum pressure difference and regular dust distribution on filtering surface were determined.
Complete chloroplast genome sequence of Murraya paniculata (Rutaceae): a widely used folk medicinal herb

Abstract Murraya paniculate, is traditionally used for management of gut, air way and cardiovascular disorders. In this study, we sequenced the complete chloroplast genome of M. paniculata based on next-generation sequencing and used the data to assess genomic resources. The chloroplast genome of M. paniculata is 160,280 bp in length consisting of large and small single-copy regions of length 87,605 and 18,609 bp, separated by two IR regions of 27,033 bp. The overall GC content was 38.61%. De novo assembly and annotation showed the presence of unique genes with 85 protein-coding genes, 29 tRNA genes, and eight rRNA genes. A maximum-likelihood phylogenomic analysis showed that M. paniculata was closely related to M. caloxylon.
Bacterial Community Structure on Membrane Surface and Characteristics of Strains Isolated from Membrane Surface in Submerged Membrane Bioreactor

Abstract In order to investigate the bacterial community structure and the characteristics of bacteria on the membrane surface, a submerged membrane bioreactor treating municipal wastewater was continuously operated under two different conditions. Bacterial community structures were examined by PCR‐denaturing gradient gel electrophoresis and PCR cloning of 16S rRNA genes. Bacterial strains isolated from membrane surface were identified and their growth curve, EPS concentration and hydrophobicity were measured. The structures of bacterial communities in the suspended solids and on the membrane surface were obviously different, and γ‐Proteobacteria more selectively adhere and grow on the membrane surface than other microorganisms. Most of the membrane isolates grew slowly as compared with the strains isolated from the suspended solids. Also, the membrane isolates were higher cell surface hydrophobicities, higher EPS concentrations, and higher ratios of protein to carbohydrate within the EPSs than the isolates from suspended solids.
Quantitative investigation of the influence of carbon surfactant on Ge surface diffusion and island nucleation on Si(100)

We investigated the surface diffusion and island nucleation of Ge on Si(100) in presence of a submonolayer coverage of carbon as surfactant by using scanning Auger microscopy and atomic force microscopy. Ge stripes have been deposited and lithographically etched on a Si substrate and used as sources for the surface diffusion of Ge promoted by annealing at 600, 650, and $700\text{ }\ifmmode^\circ\else\textdegree\fi{}\text{C}$. The diffusion coefficient has been determined by fitting the postannealing coverage profiles measured by Auger microscopy with a one-dimensional continuous model. The carbon coverage has been spatially modulated on a single sample, allowing the measurement of the diffusion coefficient as a function of the C thickness at $600\text{ }\ifmmode^\circ\else\textdegree\fi{}\text{C}$. We show that the reduction in the diffusion coefficient while increasing the surfactant coverage is described by a linear dependence of the diffusion activation energy on the C coverage. This dependence is discussed in terms of the chemical interactions among Si, C, and Ge, of the surface roughness and the local strain field induced by the C surfactant. Spontaneous nucleation of SiGe islands coexists with the continuous surface diffusion of Ge. The transition of the island nucleation as a function of the carbon coverage is observed to be continuous from the Stranski-Krastanov mode to the Volmer-Weber regime. We propose a consistent scenario correlating diffusion and nucleation parameters within a diffusion limited growth regime and show the existence of a threshold for C coverage below which no effect is observed.