Miracle-dz/UniFAR-FTUs huggingface dataset:
A model for the boundary condition of a porous material. Part 1

In problems where a viscous fluid flows past a porous solid it has frequently been assumed that the tangential component of surface velocity is zero. When the porous solid has an open structure with large pores the external surface stress may produce a tangential flow below the surface. Recently, Beavers & Joseph (1967) have assumed that the surface velocity UB depends on the mean tangential stress $[\mu(d\overline{u}/dy)]_{y=0}$ in the fluid outside the porous solid through the relation \[ \left[\mu\frac{d\overline{u}}{dy}\right]_{y=0} = \frac{\mu\alpha}{k^{\frac{1}{2}}}(U_B-Q), \] where Q is the volume flow rate per unit cross-section within the porous material due to the pressure gradient, k is the Darcy constant and α is a constant which depends only on the nature of the porosity. An artificial mathematical model of a porous medium is proposed for which the flow can be calculated both inside and outside the surface. This conceptual model was materialized and the experimental results agree with the calculations. The calculated values of α so found are not quite independent of the external means of producing the external tangential stress.
A Balanced Approximation of the One-Layer Shallow-Water Equations on a Sphere

Abstract A global version of the equivalent barotropic vorticity equation is derived for the one-layer shallow-water equations on a sphere. The equation has the same form as the corresponding beta plane version, but with one important difference: the stretching (Cressman) term in the expression of the potential vorticity retains its full dependence on f 2, where f is the Coriolis parameter. As a check of the resulting system, the dynamics of linear Rossby waves are considered. It is shown that these waves are rather accurate approximations of the westward-propagating waves of the second class of the original shallow-water equations. It is also concluded that for Rossby waves with short meridional wavelengths the factor f 2 in the stretching term can be replaced by the constant value f02, where f0 is the Coriolis parameter at ±45° latitude.
Constraining Star-Formation Driven Outflows in Local Dwarf Galaxies with Herschel†

: Galactic feedback (i.e., outﬂows) plays a fundamental role in regulating galaxy formation and evolution. We investigate the physical properties of galactic outﬂows in a sample of 29 local low-metallicity dwarf galaxies drawn from the Dwarf Galaxy Survey. We make use of Herschel/PACS archival data to detect outﬂows in the broad wings of observed [CII] 158 µ m line proﬁles. We detect outﬂowing gas in 1/3 of the sample, and in the average galaxy population through line stacking. We ﬁnd typical mass-loading factors (i.e., outﬂow efﬁciencies) of the order of unity. Outﬂow velocities are larger than the velocities required from gas to escape the gravitational potential of our targets, suggesting that a signiﬁcant amount of gas and dust is brought out of their halos. Our results will be used as input for chemical models, posing new constraints on the processes of dust production/destruction in the interstellar medium of galaxies.
Dielectric charge measurements in capacitive microelectromechanical switches

Measurements of transient currents from the discharge of microelectromechanical capacitive switches after charging the dielectric with an ion gun are reported. It is shown that both the charge sign and the charge amount can be independently measured and that the values can be related to the pull-in shift as measured from C-V characteristics. Several capacitive switches of different sizes were fabricated and subjected to charging and discharging experiments. The analysis of the transients shows that several time constants are governing the charge dynamics, one of them is related to the resistivity-permittivity product of the dielectric.
Characterization of Cystatin B Interactome in Saliva from Healthy Elderly and Alzheimer’s Disease Patients

Cystatin B is a small, multifunctional protein involved in the regulation of inflammation, innate immune response, and neuronal protection and found highly abundant in the brains of patients with Alzheimer’s disease (AD). Recently, our study demonstrated a significant association between the level of salivary cystatin B and AD. Since the protein is able to establish protein-protein interaction (PPI) in different contexts and aggregation-prone proteins and the PPI networks are relevant for AD pathogenesis, and due to the relevance of finding new AD markers in peripheral biofluids, we thought it was interesting to study the possible involvement of cystatin B in PPIs in saliva and to evaluate differences and similarities between AD and age-matched elderly healthy controls (HC). For this purpose, we applied a co-immunoprecipitation procedure and a bottom-up proteomics analysis to purify, identify, and quantify cystatin B interactors. Results demonstrated for the first time the existence of a salivary cystatin B-linked multi-protein complex composed by 82 interactors and largely expressed in the body. Interactors are involved in neutrophil activation, antimicrobial activity, modulation of the cytoskeleton and extra-cellular matrix (ECM), and glucose metabolism. Preliminary quantitative data showed significantly lower levels of triosophosphate isomerase 1 and higher levels of mucin 7, BPI, and matrix Gla protein in AD with respect to HC, suggesting implications associated with AD of altered glucose metabolism, antibacterial activities, and calcification-associated processes. Data are available via ProteomeXchange with identifiers PXD039286 and PXD030679.
Onset and cessation of time-dependent, dissolution-driven convection in porous media

Motivated by convection in the context of geological carbon dioxide sequestration, we present the conditions for free, dissolution-driven convection in a horizontal, ideal porous layer from a time-dependent, pure-diffusion base state. We assume that solute as a separate phase is instantaneously placed in the pores above a given horizontal level at time zero, and gradually diffuses into the underlying liquid. As the concentration of dissolved solute in the liquid increases, its density increases and the system may eventually become gravitationally unstable and convection may begin. We define the amplitude of a perturbation as the mean square of the difference of the concentration profile and the pure-diffusion profile. To identify instability, we calculate the maximum possible instantaneous growth rate of the amplitude over all possible infinitesimal and finite perturbations. Instability exists where this growth rate is positive. We consider two scenarios. In the first scenario, the underlying liquid canno.
Slow Fluid Antenna Multiple Access

Fluid antennas offer a novel way to achieve massive connectivity by enabling each user to find a ‘port’ in space where the instantaneous interference undergoes a deep null for multiple access. While this unprecedented capability permits hundreds of users to share the same radio channel, each user needs to switch its best port on a symbol-by-symbol basis, which is impractical. Motivated by this, this paper considers the scenario in which the fluid antenna of each user updates its best port only if the fading channel changes. We refer to this approach as <italic>slow</italic> fluid antenna multiple access (<inline-formula> <tex-math notation="LaTeX">$s$ </tex-math></inline-formula>-FAMA). In this paper, we first investigate the interference immunity of <inline-formula> <tex-math notation="LaTeX">$s$ </tex-math></inline-formula>-FAMA through analyzing the outage probability. Then an outage probability upper bound is obtained, from which we shed light on the achievable multiplexing gain of the system and unpack the impacts of various system parameters on the performance. Numerical results reveal that despite having a weaker multiplexing power than the symbol-based, <italic>fast</italic> FAMA (i.e., <inline-formula> <tex-math notation="LaTeX">$f$ </tex-math></inline-formula>-FAMA), spatial multiplexing of 4 users or more is possible if the users’ fluid antennas have large numbers of ports.
Streamer inhibition for improving force and electric wind produced by DBD actuators

The use of thin wires from 13 to 300 µm in diameter as the exposed electrode of a surface dielectric barrier discharge (SDBD) plasma actuator is experimentally investigated by electrical and optical diagnostics, electrohydrodynamic force measurements and produced electric wind characterization from time-averaged and time-resolved measurements. The streamer inhibition and glow discharge enhancement due to the use of a thin wire active electrode fully modify the topology and the temporal behaviour of the thrust and the electric wind production. With a typical plate-to-plate DBD, the electric wind velocity increases during the negative going cycle. With a wire-to-plate design, both positive and negative going-cycle discharges result in an electric wind velocity increase. The four main quantitative results are as follows: (1) for a power consumption of 1 W cm−1, the force is increased from 65 to 95 mN m−1 when a 13 µm wire is used, (2) this corresponds to a 15% electric wind velocity enhancement, (3) electromechanical efficiency can be increased from 0.1% to 0.25%, (4) these improvements are applied for definition of a new multi-DBD design plasma actuator that allows us to produce a mean velocity of 10.5 m s−1.
Using LMIs to optimize robustness of observer‐based state‐feedback for a synchrotron

In this article, a synthesis method for linear systems subject to uncertain time‐varying parameters is proposed. Starting with the given values for the nominal parameters, the first objective is to find a constant state feedback such that the controlled system is stabilized and given dynamic specifications, such as a minimal decay rate, are met. In a second step, the constant feedback is then locally optimized such that the uncertain system parameters are allowed to vary around their nominal point as much as possible, whereas stabilization and dynamic specifications still hold. In addition, the procedure is extended toward observer‐based state feedback. Finally, this approach is applied to a synchrotron example, where the particle beam in longitudinal direction is to be stabilized and the coherent synchrotron frequency as well as the damping rate are uncertain. Copyright © 2013 John Wiley & Sons, Ltd.
A Cross-Sectional and Longitudinal Study of Pain among Middle-Aged and Older Adults in Thailand

Objective The present study aimed to assess the prevalence and risk factors of pain among ageing adults in Thailand. Methods Cross-sectional and longitudinal data were analysed from two consecutive national waves of the Health, Aging, and Retirement in Thailand (HART) study in 2015 and 2017. The dependent variable pain was defined as moderate or severe pain in any of the 13 areas of the body over the past month. Independent variables included sociodemographic factors, health risk behaviour, physical and mental health conditions, and healthcare utilization. Results The baseline or cross-sectional sample consisted of 5,616 participants (≥45 years), and the follow-up or incident sample consisted of 2,305 participants. The proportion of pain in the cross-sectional/baseline sample was 36.0%, and in the incident/follow-up sample 39.9%. In the cross-sectional/baseline multivariable model, poor self-reported mental health, sleep problem, arthritis or rheumatism, brain disease and/or psychiatric problems, lung disease, use of hospital in-patient, conventional out-patient, and traditional medicine practitioners were positively associated with pain. In the incident/follow-up multivariable model, older age, Buddhist religion, class I obesity, poor self-reported mental health, hospital in-patient, private clinic out-patient, and use of a practitioner of traditional medicine were positively associated with pain. Male sex and higher education were negatively associated with both cross-sectional and incident pain. Conclusions More than one-third of older adults in Thailand had past month moderate or severe pain. Risk factors of pain from cross-sectional and/or incident analysis included older age, female sex, lower education, obesity, poor self-reported mental health, sleep problem, arthritis or rheumatism, brain disease and/or psychiatric problems, lung disease, and conventional and traditional healthcare utilization.
The Cost and Benefit of Enhancing Cybersecurity for Hybrid AC/DC Grids

As critical interfaces of AC grids and DC grids inside a hybrid AC/DC grid, the voltage-sourced-converter (VSC) has been demonstrated to be vulnerable to false data injection (FDI) cyber-attacks. As a result, the cyber-attack-induced AC grid frequency deviations and DC grid voltage deviations threaten the secure operation. To enhance cybersecurity in a not only feasible but also cost-effective manner, this paper proposes a cost-benefit-based cyber-defense strategy for a hybrid AC/DC grid. First, this paper establishes a spatial-temporal dual cyber-attack evaluation model, in which the cyber-attack-induced frequency and voltage deviations are modelled in both a spatially and temporally dual manner. Then, the proposed cost-benefit-based cyber-defense strategy is modelled as a VSC commitment problem to achieve the trade-off between maximizing the cyber-defense benefits and minimizing the cyber-defense costs. The VSC commitment problem is then mathematically convexified into a mixed-integer second-order cone programming (MISOCP) problem, which could be efficiently solved in an event-triggered manner against unfolding cyber-attack events. Simulation results on a test hybrid AC/DC grid verified the feasibility and the cost-effectiveness of the proposed cyber-defense strategy.
Chromosome Segregation and Cell Division Defects in Escherichia coli Recombination Mutants Exposed to Different DNA-Damaging Treatments

Homologous recombination repairs potentially lethal DNA lesions such as double-strand DNA breaks (DSBs) and single-strand DNA gaps (SSGs). In Escherichia coli, DSB repair is initiated by the RecBCD enzyme that resects double-strand DNA ends and loads RecA recombinase to the emerging single-strand (ss) DNA tails. SSG repair is mediated by the RecFOR protein complex that loads RecA onto the ssDNA segment of gaped duplex. In both repair pathways, RecA catalyses reactions of homologous DNA pairing and strand exchange, while RuvABC complex and RecG helicase process recombination intermediates. In this work, we have characterised cytological changes in various recombination mutants of E. coli after three different DNA-damaging treatments: (i) expression of I-SceI endonuclease, (ii) γ-irradiation, and (iii) UV-irradiation. All three treatments caused severe chromosome segregation defects and DNA-less cell formation in the ruvABC, recG, and ruvABC recG mutants. After I-SceI expression and γ-irradiation, this phenotype was efficiently suppressed by the recB mutation, indicating that cytological defects result mostly from incomplete DSB repair. In UV-irradiated cells, the recB mutation abolished cytological defects of recG mutants and also partially suppressed the cytological defects of ruvABC recG mutants. However, neither recB nor recO mutation alone could suppress the cytological defects of UV-irradiated ruvABC mutants. The suppression was achieved only by simultaneous inactivation of the recB and recO genes. Cell survival and microscopic analysis suggest that chromosome segregation defects in UV-irradiated ruvABC mutants largely result from defective processing of stalled replication forks. The results of this study show that chromosome morphology is a valuable marker in genetic analyses of recombinational repair in E. coli.
UNIFORM SPECTRAL ASYMPTOTICS FOR SINGULARLY PERTURBED LOCALLY PERIODIC OPERATORS

ABSTRACT We consider the homogenization of the spectral problem for a singularly perturbed diffusion equation in a periodic medium. Denoting by ε the period, the diffusion coefficients are scaled as ε2 and vary both on the macroscopic scale and on the periodic microscopic scale. We make a structural hypothesis on the first cell eigenvalue, which is assumed to admit a unique minimum in the domain with non-degenerate quadratic behavior. We then prove an exponential localization phenomena at this minimum point. Namely, the k-th original eigenfunction is shown to be asymptotically given by the product of the first cell eigenfunction (at the ϵ scale) times the k-th eigenfunction of an homogenized problem (at the scale). The homogenized problem is a diffusion equation with quadratic potential in the whole space. We first perform asymptotic expansions, and then prove convergence by using a factorization strategy.
Dispersed droplet dynamics during produced water treatment in oil industry

For Lagrangian particle tracking applied to swirling flow produced water treatment the influence of the history force is investigated. In the expression for the history force an existing Reynolds number dependent kernel is adapted and validated for a range of experimental data for settling spheres. This kernel is used during the numerical simulation of oil-droplets in an idealized flow field as model for flow fields observed in swirling flow separators. It is shown that the history force should not be neglected for the motion of particles in such flows. However, for this specific type of flow it is shown that the contribution of the history force might be approximated as a drag-like expression. Subsequently, an efficient collision detection mechanism is developed to obtain collision detection with a work-load of O(Np lnNp). The scheme is validated for settling spheres and applied to the swirling flow field used during the investigation of the influence of the history force. Finally, two approaches for the lattice Boltzmann method, taking into account the equation of state for water, are presented. One approach utilizing a pressure corrected BGK approximation, the other a dense gas BBGKY approximation. A novel approach is used to obtain the macroscopic quantities and boundary conditions. It is shown that for modeling the flow of water around a particle an ideal-gas lattice Boltzmann method to simulate water is not capable of capturing all relevant details. However, modeling the flow with both proposed approaches, which take the equation of state into account, lead to similar results.
Copeptin, the prediction of poor ovarian reserve and the infertile women: Correspondence

We wants to share ideas on the publication “A potential marker for predicting poor ovarian reserve (POR) in the infertile women(1). ” To determine the association between the level of serum copeptin and the presence of POR in infertile women, Görkem and Yıldırım(1) conducted their research. According to Görkem and Yıldırım(1), this investigation verified that the infertile women with POR had a higher blood copeptin concentration and that copeptin may have a predictive value for developing POR. To elucidate the potential impacts of copeptin in the POR pathogenesis, future large-scale prospective investigations are necessary(1). We both agree that copeptin may be effective for ovarian reserve prediction. But it’s important to be aware of any confounding factors. The interpretation needs to be careful in areas where hemoglobinopathy is prevalent. High levels of copeptin have been linked to thalassemia(2).
The potential impact of a vaccine on Neisseria gonorrhoeae prevalence among heterosexuals living in a high prevalence setting.

BACKGROUND Treatment of Neisseria gonorrhoeae is under threat with the emergence and spread of antimicrobial resistance. Thus, there is a growing interest in the development of a gonorrhoea vaccine. We used mathematical modelling to assess the impact of a hypothetical vaccine in controlling gonorrhoea among heterosexuals living in a setting of relatively high N. gonorrhoeae prevalence (∼3 %). METHODS We developed a mathematical model of N. gonorrhoeae transmission among 15-49-year-old heterosexuals, stratified by age and sex, and calibrated to prevalence and sexual behaviour data from South Africa as an example of a high prevalence setting for which we have data available. Using this model, we assessed the potential impact of a vaccine on N. gonorrhoeae prevalence in the entire population. We considered gonorrhoea vaccines having differing impacts on N. gonorrhoeae infection and transmission and offered to different age-groups. RESULTS The model predicts that N. gonorrhoeae prevalence can be reduced by ∼50 % in 10 years following introduction of a vaccine if annual vaccination uptake is 10 %, vaccine efficacy against acquisition of infection is 25 % and duration of protection is 5 years, with vaccination available to the entire population of 15-49-year-olds. If only 15-24-year-olds are vaccinated, the predicted reduction in prevalence in the entire population is 25 % with equivalent vaccine characteristics and uptake. Although predicted reductions in prevalence for vaccination programmes targeting only high-activity individuals and the entire population are similar over the same period, vaccinating only high-activity individuals is more efficient as the cumulative number of vaccinations needed to reduce prevalence in the entire population by 50 % is ∼3 times lower for this programme. CONCLUSION Provision of a gonorrhoea vaccine could lead to substantial reductions in N. gonorrhoeae prevalence in a high prevalence heterosexual setting, even with moderate annual vaccination uptake of a vaccine with partial efficacy.
Mothers' Knowledge and Self-efficacy on Preventing Infections in Low-birth-weight Infants during the COVID-19 Pandemic

Low birth weight (LBW) infants are at risk for vertical and horizontal transmission of COVID-19. A mother’s ability to prevent infection in LBW infants is decided by their knowledge, self-efficacy, and abilities of the mother in carrying out infection-prevention care. This study aimed to analyze the relationship between mothers’ knowledge and self-efficacy with their ability to prevent infection in LBW infants during the COVID-19 pandemic. This study used a correlational design. This study included 84 respondents who were selected through purposive sampling in the perinatology room. The statistical test used was the Spearman Rho. The outcomes confirmed a relationship between a mother’s knowledge (r = 0.249; p = 0.022) and self-efficacy (r = 0.313; p = 0.004) with the mother’s ability to prevent infection in LBW infants. The level of strength of the positive relationship between a mother’s knowledge and the mother’s ability to prevent infection in LBW infants is 0.249, or very vulnerable. The level of the strength of the positive relationship between maternal self-efficacy and the mother’s ability to prevent infection in LBW infants is 0.313, or sufficient. Therefore, increased knowledge and self-efficacy of mothers may have an impact on increasing the ability of mothers to prevent infection in LBW. Keywords: knowledge, self-efficacy, ability to prevent infection, low birth weight, COVID-19 pandemic
County Immigration Enforcement in the Context of Unsettled Federalism: From Obama to Trump

We examine patterns of county participation in immigration enforcement across the Obama and Trump administrations and responses to the Trump administration’s efforts to mandate local compliance with Immigration and Customs Enforcement (ICE) directives. We focus on the policy that directly speaks to local discretion in enforcing federal law—namely, the willingness of local officials to render immigrant detainees to ICE. We find that underlying patterns of detainee transfers from counties to ICE were largely consistent between the Obama and Trump administrations. Nonetheless, the rate of detainee transfers increased during the Trump administration, an outcome associated with county support for Trump in the 2016 election. The findings suggest that partisanship is an entrenched source of diverging county enforcement practices, increasing intergovernmental conflict and undermining the “steam valve” potential of immigration federalism.