Effect of straw reinforcement on the shearing and creep behaviours of Quaternary loess

In addition to the shearing behavior of soil, the creep character is also considered crucial in determining the long-term shear strength. This especially holds true for the loess that possesses the metastable microstructure and is prone to landslide hazards. This study explored the potential application of straw reinforcement to enhance the shearing and creep properties of the Quaternary loess. The mechanism responsible for the straw reinforcement to elevate the peak shear strength was revealed. Furthermore, three creep characters, namely attenuating creep, non-attenuating creep, and viscous flow were identified in this study. The unreinforced and reinforced specimen behaved in a different manner under identical shear stress ratio condition. The reinforced specimen was superior in limiting the particle relative movement within the shear plane than the unreinforced specimen. The chain reaction of interparticle contact loss, accompanied with excessive viscous displacement, rapid weakening of creep resistance, and eventually accelerated creep displacement, provided an evidence for the formation mechanism of slow-moving landslide. The long-term shear strength using the isochronal stress–strain relationship may be used for optimising the design of high-fill embankment works.

Aging Effects on Categorical Perception of Mandarin Lexical Tones in Noise

Purpose The purpose of this study was to examine the aging effects on the categorical perception (CP) of Mandarin lexical Tones 1–4 and Tones 1–2 in noise. It also investigated whether listeners' categorical tone perception in noise correlated with their general tone identification of 20 natural vowel-plus-tone signals in noise. Method Twelve younger and 12 older listeners with normal hearing were recruited in both tone identification and discrimination tasks in a CP paradigm where fundamental frequency contours of target stimuli varied systematically from the flat tone (Tone 1) to the rising/falling tones (Tones 2/4). Both tasks were conducted in quiet and noise with signal-to-noise ratios set at −5 and −10 dB, respectively, and general tone identification of natural speech signals was also tested in noise conditions. Results Compared with younger listeners, older listeners had shallower identification slopes and smaller discrimination peakedness in Tones 1–2/4 perception in all listening conditions, except for Tones 1–4 perception in quiet where no group differences were found. Meanwhile, noise affected Tones 1–2/4 perception: The signal-to-noise ratio condition at −10 dB brought shallower slope in Tones 1–2/4 identification and less peakedness in Tones 1–4 discrimination for both listener groups. Older listeners' CP in noise, the identification slopes in particular, positively correlated with their general tone identification in noise, but such correlations were partially missing for younger listeners. Conclusions Both aging and the presence of speech-shaped noise significantly reduced the CP of Mandarin Tones 1–2/4. Listeners' Mandarin tone recognition may be related to their CP of Mandarin tones.

The Traces Left Behind

Fulfilling one’s all-things-considered duty sometimes requires violating pro tanto duties. According to W. D. Ross and Robert Nozick, the pro tanto-duty-violating, wrong-making features of acts in these cases can leave ‘traces’ of wrongfulness that require specific responses: feeling compunction for the wrongfulness and/or providing compensation to the negatively affected person. Failure to respond in the appropriate way to lingering wrong-making features can itself be wrongful. Unfortunately, criteria for determining when traces remain are largely lacking. In this piece, I argue for three necessary conditions for the existence of a trace: ‘The Non-Consequentialist Duty Condition,’ ‘The Identity Condition,’ and ‘The Ratio Condition.’

Design of Howland current sources using differential evolution optimization

Howland circuits have been widely used in Electrical Bioimpedance Spectroscopy applications as reliable current sources. This paper presents an algorithm based on Differential Evolution for the automated design of Enhanced Howland Sources according to arbitrary design constraints while respecting the Howland ratio condition. Results showed that the algorithm can obtain solutions to commonly sought objectives, such as maximizing the output impedance at a given frequency, making it a versatile method to be employed in the design of sources with specific requirements. The mathematical modeling of the source output impedance and transconductance, considering a non-ideal operational amplifier, was validated against SPICE simulations, with results matching up to 10 MHz.

Tax-to-GDP Ratio and the Relation of Tax Revenue with GDP: Nepalese Perspective

This study aims to show the tax-to-GDP ratio condition and explore the relation of tax revenue with Nepal's GDP. It is based on the secondary data that is collected from various published sources. Descriptive and exploratory research designs are used to explore the relationship between tax revenue and GDP. Some statistical and econometric tools like mean, depression, correlation, Johnsen Co-integration Test, Vector Error Correction Model (VECM), serial correlation, heteroskedasticity test, and normality test are used. There is a high degree of the positive relationship between tax revenue and GDP of Nepal. The tax revenue and GDP are co-integrated, or they have a long-run association ship. The tax-to-GDP ratio of Nepal lies in the high rank among the various developing countries. So, tax to GDP ratio alone cannot ensure its economic growth. It is advised to the concerned authorities to increase the income to increase the tax revenue; otherwise, it increases the general public's dissatisfaction with the government.

Sex disparities determined by biometric and hematological measurements in Astyanax bimaculatus

ABSTRACT This study aimed to compare the body indexes and hematological characteristics between Astyanax bimaculatus males and females. Four hundred fish were randomly distributed into four polyethylene tanks (100 fish/unit) in a recirculation system and fed four times a day (3% of biomass). After 90 days, ten fish (five ♀ and five ♂) were removed to perform blood tests and to measure weight, height, total length, height/length ratio, condition factor and index determination: vicerosomatic (VSI), hepatosomatic (HSI), and gonadosomatic (GSI). The results showed a higher average weight (g) in females (12.32±0.71) compared to males (6.98±0.75), the same happened to height (cm) = (3.01±0.07) and (2.40±0.05), total length (cm) = (3.01±0.07) and (2.40±0.05), VSI (%) = (11.43±0.81) and (3.55±1.05), HSI (%) = (0.72±0.08) and (0.30±0.04), respectively. Mean corpuscular hemoglobin (pg) was higher in females (3.72±1.20) than in males (2.99±1.51). Regarding the number of thrombocytes (103.µL-1), there was an increase in males (25.71±3.91) compared to females (17.40±6.40).

Wind Tunnel Test of the Icing Characteristics of Airfoil Rotating around a Vertical Axis

To determine the process of icing on the rotating machinery, an icing experiment on a rotating airfoil blade was carried out in this paper. First, an icing wind tunnel was fabricated, and its conditional parameters were calibrated. The calibration results showed that the performance of this icing wind tunnel was reliable and stable. The experimental temperature was -15°C, and the MVD was 50 μm. Then, an icing experiment on the rotating blade with the NACA0018 airfoil was carried out. The characteristics of icing, including icing distribution, growth rate of icing, and thickness of the ice layer, were defined and quantitatively analyzed under different tip speed ratios and setting angles. The results show that the type of icing changes from rime ice to glaze ice with an increase in the tip speed ratio. The dimensionless icing area and dimensionless thickness of the ice layer both increase with an increase in the icing time. The growth rate of icing increases rapidly at the initial icing stage and then decreases dramatically under each tip speed ratio condition.

Wharton’s Jelly-derived mesenchymal stromal cells retain their immunophenotype and immunomodulating characteristics after transfection with polyethylenimine

BackgroundWharton’s Jelly-derived mesenchymal stromal cells (WJ-MSCs) present several advantages over other sources of multipotent stem cells, not only because they are obtained from neonatal umbilical cord, which is considered a biological waste, but also display higher proliferation rate and low senescence at later passages compared to stromal cells obtained from other sources. In the field of tissue engineering, WJ-MSCs have a wide therapeutic potential, due to their multipotential capacity, which can be reinforced if cells are genetically modified to direct their differentiation towards a specific lineage; unfortunately, as primary cells, WJ-MSC are difficult to transfect. Therefore, the objective of the present work was to standardize a protocol for the transfection of WJ-MSCs using a cationic polymer. Such protocol is important for future developments that contemplate the genetic modification of WJ-MSCs for therapeutic purposes.MethodsIn this work, WJ-MSCs were genetically modified using polyethylenimine (PEI) and a lentiviral plasmid that encodes for green fluorescent protein (pGFP). To achieve WJ-MSCs transfection, complexes between PEI and pGFP, varying its composition (N/P ratio), were evaluated and characterized by size, zeta potential and cytotoxicity. At the N/P ratio condition where the highest transfection efficiencies were obtained, immunophenotype, immunomodulation properties and multipotential capacity of WJ-MSCs were evaluated.ResultsHere, we present the standardization of the transfection conditions of the WJ-MSCs in a monolayer culture with PEI. The concentrations of plasmid and PEI that have the best transfection efficiencies were establishedConclusionsTransfection with PEI doesn’t affect immunophenotype, immunomodulatory properties and differentiation capacity of WJ-MSCs.