Miracle-dz/UniFAR-FTUs huggingface dataset:
Jackknife variance estimation with survey data under hot deck imputation

SUMMARY Hot deck imputation is commonly employed for item nonresponse in sample surveys. It is also a common practice to treat the imputed values as if they are true values, and then compute the variance estimates using standard formulae. This procedure, however, could lead to serious underestimation of the true variance, when the proportion of missing values for an item is appreciable. We propose a jackknife variance estimator for stratified multistage surveys which is obtained by first adjusting the imputed values for each pseudo-replicate and then applying the standard jackknife formula. The proposed jackknife variance estimator is shown to be consistent as the sample size increases, assuming equal response probabilities within imputation classes and using a particular hot deck imputation.
The recurrence structure of general Markov processes

We study properties of a Markov process (X) with transition semigroup {P'(x, A)} in terms of the properties of the associated Markov chains with one-step transition probabilities KF(x, A) =JP'(x, A)F(dt) where F is a distribution on [0,00) with finite mean. We show that if (X) is Hunt, then (X,) and KF have the same recurrence structures if F has some convolution power non-singular with respect to Lebesgue measure; and if P' is continuous in t this extends to lattice F, and to arbitrary F if the continuity is uniform in the neighbourhoods of infinity. Here, by recurrence structures we mean such properties as a given subset being a maximal closed set or a maxima\ Harris set, or a grven maximal c,\()~ed set being indecomposable and properly essential or being not properly essential. This extends and unifies known results for resolvent chains (F exponential) and skeleton chains (F concentrated at h > 0).
Lyapunov function for power systems with transfer conductances: extension of the invariance principle

Summary form only given. In many engineering and physical problems, it is very difficult to find a Lyapunov function satisfying the classical version of the LaSalle's invariance principle. This difficulty has been a big drawback in the application of energetic methods to stability analysis of power systems with more realistic models. In this work, an extension of the invariance principle is used to support the proposal of a new function, which is an extended Lyapunov function for power systems incorporating the transfer conductances. This function was tested in a single-machine-infinite-bus system and also in some multimachine systems. The results show that the proposed function can be used to obtain good estimates of the critical clearing time.
CCD photometry of the distant young open cluster NGC 7510

CCD observations in B, V, and I passbands have been used to generate deep V, (B-V), and V,(V-I) color-magnitude diagrams for the open cluster NGC 7510. The sample consists of 592 stars reaching down to V = 21 mag. There appears to be nonuniform extinction over the face of the cluster with the value of color excess, E(B-V), ranging from 1.0 to 1.3 mag. The law of interstellar extinction in the direction of the cluster is found to be normal. A broad main sequence is clearly visible in both color-magnitude diagrams. From the bluest part of the color-magnitude diagrams, the true distance modulus to the cluster has been estimated as 12.5 ± 0.3 mag and an upper limit of 10 Myr has been assigned for the cluster age.
Adalimumab Serum Concentrations, Clinical and Endoscopic Disease Activity in Crohn’s Disease: A Cross-Sectional Multicentric Latin American Study

Despite some variability in ideal serum Adalimumab (ADA) concentrations, there is increasing evidence that higher concentrations of anti-TNF-α agents can be associated with sustained efficacy, and low or undetectable levels may lead to loss of response. This study aims to correlate serum ADA concentrations with clinical and endoscopic activity in patients with Crohn’s disease (CD). A cross-sectional and multicentric study was performed with patients with CD, who used ADA for at least 24 weeks. Patients were allocated into groups according to the presence of clinical or endoscopic disease activity. Serum ADA concentrations were measured and compared between groups. Overall, 89 patients were included. A total of 27 patients had clinically active CD and 62 were in clinical remission. Forty patients had endoscopic disease activity and 49 were in endoscopic remission. The mean serum ADA concentration was 10.2 μg/mL in patients with clinically active CD and 14.3 μg/mL in patients in clinical remission (p = 0.395). The mean serum ADA concentration in patients with endoscopic activity was 11.3 μg/mL as compared to 14.5 μg/mL in those with endoscopic remission (p = 0.566). There was no difference between serum ADA concentrations regarding clinical or endoscopic activity in CD, as compared to patients in remission
Improving Informative Writing in Inclusive and Linguistically-Diverse Elementary Classes through Self-Regulated Strategy Development

ABSTRACT Developing informative writing skills at the elementary level is critical for long-term academic and personal success. This study investigated impacts of a schoolwide implementation of Self-Regulated Strategy Development (SRSD) in inclusive classes to improve elementary students’ informative writing and teachers’ efficacy and perceptions of teaching SRSD for writing. Eighteen kindergarten through fifth-grade teachers participated in professional development and implemented SRSD with 276 students. Multilevel modeling was used to examine how students’ improvement in writing performance varied by their gender, classification (general education – receiving no additional services, receiving special education services, English Learners [ELs], and special education and EL), and number of lessons received. Student writing was scored for genre elements, holistic quality, total words written, and transition words. Results demonstrate that students in all grades improved on all measures. Gain scores of informative genre elements, holistic quality, and transition words remained significant even after controlling for student gender, classification, and the number of lessons received. In addition, teachers reported feeling more confident and skillful in teaching writing through SRSD.
Estimating contribution of permafrost to lake expansion by SBAS-InSAR: a case study from Hohxil Lake basin in the Tibetan Plateau

Due to climate warming and increased precipitation, the permafrost of the Tibet Plateau (TP) has undergone serious degradation along with obvious lake expansion in recent decades. Model simulation is often used to analyze the contribution of permafrost melting to lake expansion, which may have many limitations. Taking Hohxil Lake (HL) basin over north TP as an example, this study makes full use of Sentinel-1 images by an improved small baseline subset interferometric technique (SBAS-InSAR), monitors the permafrost deformation from 2015 to 2020, and estimates its contribution to the lake expansion. The results show that the permafrost settlements mainly occur in the flat terrain around HL. The average line of sight (LOS) de-formation rate of permafrost is -3.59 ± 0.001 cm/yr, where there existed many obvious funnel-shaped thawing areas around the lake, indicating a close relationship between lake expansion and permafrost under-ground ice melting. The long-term linear deformation rate of underground ice is inverted by the traditional linear model, and the melting rate is estimated to be (31.17 ± 0.0054) ×106 m3/yr with 9.3% contribution to the HL expansion. This study takes full advantage of Interferometric Synthetic Aperture Radar (InSAR) to quantitatively analyze the contribution of permafrost to lake expansion, which provides a new insight into the study of permafrost hydrological process and the proposed method can be easily extended to analyze lake water budget for underground ice in other watershed over the TP.
Spectral Analysis of Velocity Fluctuations in the Vicinity of a Bias Flow Liner With Respect to the Damping Efficiency

Bias flow liners are perforated walls with an additional bias flow through the perforation. A common application is their integration in walls of hot gas areas, e.g. in combustion chambers of aero engines, for cooling. It is wellknown for a long time that the bias flow additionally provides a substantial amount of acoustic damping. However, until now the detailed damping mechanisms are not fully understood. Therefore, this study takes a closer look at the energy transfer from a propagating acoustic wave to the flow velocity field, which can be measured in the vicinity of the perforated wall. Two laser-optical measurement techniques, Doppler global velocimetry with sinusoidal laser frequency modulation (FM-DGV) and acoustic particle image velocimetry (A-PIV), were applied to a bias flow liner. The time-continuous velocity signal measured by FM-DGV was used to perform a spectral analysis of the fluctuating velocity components above the liner surface. This was done for different acousticexcitation frequencies, where the liner exhibits different dissipation rates. After removal of the acoustic Content from the power spectral density, the hydrodynamic velocity components feature a spectral augmentation in the vicinity of the excitation frequency. The effect appears downstream of the holes. The amount of spectral Augmentation correlates to the dissipation rate of the liner at the different excitation frequencies. Consequently, a certain transfer of acoustic energy into turbulent velocity fluctuations occurs in different frequency regimes. This energy transfer is, as a matter of fact, a function of the dissipation rate of the liner. Moreover, it has a strong dependence on the spatial location with respect to the orifice of the bias flow liner.
The Accuracy of Sea Ice Drafts Measured from U.S. Navy Submarines

Abstract Navy submarines in the Arctic Ocean routinely obtain observations from an upward-looking sonar of the draft of the sea ice cover overhead. Draft data are now publicly available from some 40 cruises from 1975 to 2000 covering over 120 000 km of track in roughly the central half of the Arctic Ocean. To apply these observations to geophysics, error estimates are needed. This paper assesses how well the correction of the data during normal processing accounts for the major sources of error in the draft data from U.S. Navy submarines and what errors remain in the data. The error treated is the error for the average draft over tens of kilometers. The following sources of error are considered: measurement precision error; errors in identifying open water (as ice of zero draft); sound speed error; errors caused by variable sonar footprint size, by uncontrolled gain and thresholds, and by ship’s trim; and differences between data from analog charts and digitally recorded data. The bias with respect to the.
Gentle spilling breakers: crest profile evolution

The surface profile histories of gentle spilling breakers generated mechanically with a dispersive focusing technique are studied experimentally. Froude-scaled generation conditions are used to produce waves with three average frequencies: f0=1.42, 1.26, and 1.15 Hz. At each frequency, the strength of the breaker is varied by varying the overall amplitude of the wavemaker motion. It is found that in all cases the beginning of the breaking process is marked by the formation of a bulge in the profile at the crest on the forward face of the wave. The leading edge of this bulge is called the toe. As the breaking process continues, the bulge becomes more pronounced while the toe remains in nearly a fixed position relative to the crest. Capillary waves form ahead of the toe. At a time of about 0.1/f0 after the bulge first becomes visible, the toe begins to move down the face of the wave and very quickly accelerates to a constant velocity which scales with the wave crest speed. During this phase of the breaker evolution, the surface profile between the toe and the crest develops ripples which eventually are left behind the wave crest. It is found that the height of the toe above the mean water level scales with the nominal wavelength λ0=g/(2πf20) of the breaker, while the size and shape of the bulge and the length of the capillary waves ahead of the toe are independent of f0.
Reduced reflectance and altered color: The potential cost of external particulate matter accumulation on urban Rock Pigeon (Columba livia) feathers

Feather quality in birds is considered an honest signal of individual health as feather appearance and function depend on an individual’s ability to maintain them. In addition to flight and insulation, feathers are essential for social interactions and sexual selection in the form of visual signals. Airborne particulate matter (PM) can accumulate on feather surfaces and alter feather appearance. We quantified PM accumulation on Rock Pigeon (Columba livia) feathers and analyzed the spectral properties of extracted particulates. Feathers were sampled from two pigeon populations, one rural and one urban, in the Dallas-Fort Worth area, with 47 and 93% developed land cover, respectively, within 2 km of the populations. We determined accumulated PM gravimetrically after rinsing feathers and then measured the visible-near-infrared diffuse reflectance and color properties of extracted particulates. The rate of PM accumulation on rural birds was higher than on urban birds. However, feather particulates collected from urban pigeons had significantly lower total reflectance, reflectance in the visible portion of the spectrum, lightness, and hue angle compared to those of rural pigeons. The hue angle of rural feather particulates displayed a negative relationship with PM accumulation while total reflectance, reflectance in the visible range, and lightness of urban feather particulates were negatively related to PM accumulation. Our findings suggest that wild birds could incur an urban pollution penalty as PM accumulation has the potential to alter feather properties. Further research is needed to better understand the influence of external PM accumulation on the physiological and behavioral health of birds.
Effect of Phylantus ninuri leaf extract on kidney and liver histopathological features in formaldehyde-exposed rats

Formaldehyde (FA) metabolism in the body reduces glutathione levels, resulting in liver and kidney damage. Phylantus ninuri (meniran) has been demontrated to have hepatoprotective properties. However, the effect of meniran administration on the histological features of the liver and kidney in in formaldehyde-exposed rats has not been adequately studied. The study was aimed to determine the effect of meniran on the histopathological feature of liver and kidney cell. This was a posttest randomized control group design. A total of 24 male Wistar rats were divided into 4 groups of 6 rats each. Group 1 was a control group that received only oral formaldehyde. Group 2, Group 3, Group 4 was administered oral formaldehyde together with meniran extract at dose of 100 mg/kg BW, 200 mg/kg BW, and 300 mg /kg BW respectively for 14 days. The histopathological changes of the kidneys and liver were assesed using hematoxylin and eosin (HE) staining. The mean of kidney and liver damage in the meniran group at various doses was lower than that of control group. There was a significant difference in the mean of kidney damage between the control group and the meniran group at various doses (p<0.05). The mean histopathological score of liver damage showed a significant difference between the control group and various treatments (p<0.05). Ethanolic extract of meniran leaves ameliorates liver and kidney damage in formaldehyde-exposed rats.
Well-posedness of feedback systems: insights into exact robustness analysis

This paper establishes a general framework for robust stability analysis of linear time-invariant uncertain systems. The uncertainty is assumed to belong to an arbitrary subset of complex matrices. The key concept used here is well-posedness of feedback systems, leading to necessary and sufficient conditions for robust stability. Based on this concept, some insights into exact robust stability conditions are given.
Microdegree azimuth polarimeter using optical heterodyne detection

We have developed a highly accurate azimuth polarimeter using an optical heterodyne technique with a single-mode laser diode as a light source. Its minimum detectable rotation angle is 0.198 µdeg √ W/Hz ; i.e., it is inversely proportional to the square root of the laser power. Using a glass cell of 1-mm optical path length, we have also successfully observed the optical rotatory power of an aqueous glucose solution whose density is close to that of glucose in human blood.
Online Reinforcement Learning for Beam Tracking and Rate Adaptation in Millimeter-Wave Systems

In this article, we propose MAMBA, a restless multi-armed bandit framework for beam tracking in directional millimeter-wave (mmW) cellular systems. Instead of relying on explicit control messages, MAMBA utilizes the ACK/NACK packets transmitted by user equipments (UEs) to the base station (BS) as a part of the hybrid automatic repeat request (HARQ) procedure. These packets are used to measure the quality of the currently operating downlink beam, and select a new downlink beam along with an appropriate modulation and coding scheme (MCS) for future transmissions. At its core, MAMBA implements an online reinforcement learning technique called adaptive Thompson sampling (ATS), which determines a good beam and associated MCS to be used for the upcoming transmissions. To evaluate MAMBA's performance, we conduct extensive simulations and over-the-air (OTA) experiments over the 28 GHz band using phased-array antennas. We study fixed- as well as adaptive-rate variants of MAMBA, and contrast it with four other beam tracking strategies: a beam selection scheme similar to the one used in 5G NR (called ‘static oracle’), a theoretically optimal but practically infeasible beam tracking scheme (called ‘dynamic oracle’), an <inline-formula><tex-math notation="LaTeX">$\epsilon$</tex-math><alternatives><mml:math><mml:mi>ε</mml:mi></mml:math><inline-graphic xlink:href="krunz-ieq1-3243910.gif"/></alternatives></inline-formula>-greedy algorithm (Mohamed 2021), and the Unimodal Beam Alignment (UBA) algorithm (Hashemi et al. 2018). Our results show that MAMBA achieves 182% throughput gain over the ‘static oracle’ and is reasonably close to the throughput of the ‘dynamic oracle’. Compared to UBA, MAMBA achieves 25-35% gain in throughput, depending on UE mobility. Finally, when operated at a fixed MCS, MAMBA/ATS achieves 21% gain over the <inline-formula><tex-math notation="LaTeX">$\epsilon$</tex-math><alternatives><mml:math><mml:mi>ε</mml:mi></mml:math><inline-graphic xlink:href="krunz-ieq2-3243910.gif"/></alternatives></inline-formula>-greedy algorithm at the lowest applied MCS index, and 255% gain at the highest MCS index.
Propaganda Information of Internet Celebrity Influence: Young Adult Purchase Intention by Big Data Analysis

At present, internet celebrity marketing has become a driving force for the growth of mobile e-commerce; however, it has also become more apparent that the credibility and authenticity of the internet celebrity is directly correlated to the success of the marketing model. Therefore, in order to entice consumers into purchasing products, cooperations and internet celebrities must be deemed trustworthy. In addition, there are several factors that influence the trust between internet celebrities and consumers. To highlight these factors, this paper constructed an internet celebrity marketing model from the perspective of trust and takes internet celebrity features, marketing character, and product factor as three constructs. Furthermore, eight independent variables are defined, and the corresponding items are designed. Through a quite large data survey and analysis, they have three findings: all eight independent variables have significant influence on trust, and internet celebrities' popularity, interactivity, and professionalism are the top three important factors.
The Structure and Decay of a Rainband in Hurricane Irene (1981)

Abstract The mesoscale thermodynamic, kinematic and reflectivity structure of a rainband observed in Hurricane Irene on 27 September 1981 is presented. Data are from 16 aircraft passes, from 150 to 4700 m MSL through the rainband which was located SSW of the circulation center of the northward moving hurricane. Cross sections of the rainband as a function of height and radial distance from the storm center reveal the following: 1) little or no decrease of θe in the subcloud layer associated with the weak convective cells in the rainband; 2) large differences in static stability between the north and south sides of the band; 3) a change of the radial wind component in the subcloud layer, from flow toward the circulation center to flow away from it as the rainband weakens. The decay of the rainband is believed to be related to mesoscale subsidence and the location of the rainband relative to the motion of the hurricane. Melting and evaporation of hydrometeors falling between the eyewall and the rainband are.
Aspects of the energetics of the upper stratosphere during the January-February 1973 major sudden warming

Data from the Nimbus 5 selective chopper radiometer have been used to study certain features of the dynamics and energetics of the January-February 1973 sudden warming. Daily values of the energetics of the upper stratosphere during a sudden warming have been calculated. Analyses of the rates of change of temperature and geopotential wave amplitude give no support to the suggestion that the disturbance suffers a time lag with increasing height. Maximum rate of warming is shown to descend from the upper stratosphere. Interaction between travelling and quasi-stationary waves did not appear to be important in the development of the warming. Two main results arise from an analysis of the latitudinal distributions of the energetics. Firstly there is good evidence to suggest that the amplification of the temperature wave between 10 and 2mb results from a transfer of eddy potential energy from the 50–10mb layer, and not from the lower stratosphere or troposphere below 50mb. However, energy propagation above 2mb is initiated by a large increase in energy flux through the 50mb level. Secondly, despite considerable uncertainty in the kinetic energy budgets, it appears that eddy kinetic energy increases in high latitudes as a result of convergence of the vertical energy flux but increases in middle latitudes as a result of barotropic conversion from the zonal flow. The westerly zonal flow is decelerated in mid-latitudes and initially accelerated in high latitudes by divergence and convergence of large poleward eddy momentum transport. Eventually the effect of the induced mean meridional circulation leads to easterly acceleration in high as well as middle latitudes. Some strong resemblances are found in the numerically simulated zonal flow changes of some model warmings which show a meridional lag in the onset of easterly acceleration.