Robust Determination Research Articles

Validation of PCR-based Markers Associated with Sex Determination in Date Palm (Phoenix dactylifera L.)

Phoenix dactylifera (Date palm) is one of the essential commercial and economical fruit crops which mainly grows in hot arid areas. A good source of food, shelter, and energy, date palm is widely known due to its unique characteristics. The dioecious nature of date palm made it challenging to prognosticate its sex until they flower almost 5 to 8 years after plantation. Researchers have developed many strategies to determine sex, including morphological study, biochemical studies, molecular-based studies as sequence characterized amplified regions (SCAR), randomly amplified polymorphic DNA (RAPD) marker, and polymerase chain reaction (PCR) assays, but still more endeavours are integral. To foretell sex at the seedling stage, specific PCR primers were employed in this study. These primers were designed on sex-linked regions that determine their gender. Date palm DNA was extracted through the CTAB method. The DNA was then amplified through PCR using sex-linked specific primers. PCR products have run on gel electrophoresis using 1.2% agarose to score the bands for sex determination. Four primers were employed in this study to determine sex. Two primers were SCAR markers, and one was a sex-linked tetra primer. Tetra-primer amplified the double band fragment of 430 and 320bp respectively in male plants, while a band of 430bp was amplified in female plants. The other primer named ALAMER1 was amplified by the single band fragment of 186bp in males with no band in females. The fourth primer, named as SCARdp, amplified the band fragment of 354bp fragment in males. These SCAR markers were established to be male-specific. Sex-linked markers provide a platform for robust, efficient, and accurate determination of sex in date palms.

When Political Ignorance is really harmful for Democracy: Moral Intuitions and Biased Attitudes in Voting Behaviour

Ignorance about political related issues has long been considered a threat to democracy. This paper revolves around the concept of political ignorance, focusing especially on Ilya Somin’s book Democracy and Political Ignorance and going beyond his standpoint in two ways. First of all, it moves away from the notion of factual knowledge by showing that political ignorance cannot be limited to a matter of information quality. On the contrary, it shows that ignorance concerns the formation of opinions about political facts, which are the bricks with which disagreement is built. Then, using the insights of the Moral Foundation Theory by Jonathan Haidt and his colleagues, the paper argues that moral intuitions represent an additional source of bias that current research on the problem of voters’ ignorance should address. While Somin argues that biased moral values are the outcome of ignorance, Moral Foundation Theory suggests that moral intuitions are a robust determinant of people’s political views as they make factual knowledge partially irrelevant and also make people with different moral minds unable to understand the basis of reciprocal factual argumentations.

Low-cost voltammetric sensors for robust determination of toxic Cd(II) and Pb(II) in environment and food based on shuttle-like α-Fe2O3 nanoparticles decorated β-Bi2O3 microspheres

Simultaneous determination of multiple heavy metal ions (HMIs) at trace level is of great significance for the environmental protection. Herein, a cost-effective voltammetric sensor was designed for the simultaneous determination of toxic Cd(II) and Pb(II) using shuttle-like α-Fe2O3 nanoparticles decorated β-Bi2O3 microspheres. After introducing the Fe2O3/Bi2O3 nanocomposites, the electroactive surface area and roughness factor increased significantly. The Fe2O3/Bi2O3 nanocomposites exhibited superior electrocatalytic activity than other modified electrodes, probably because the synergistic interaction between Fe2O3 and Bi2O3 greatly facilitated the deposition-stripping process. The Fe2O3/Bi2O3/GCE realized the simultaneous determination of nanomolar Cd(II) and Pb(II) with a wide dynamic range of 0.002–4 μM. Moreover, the Fe2O3/Bi2O3 nanocomposites showed robust stability in the voltammetric responses up to three weeks and excellent selectivity against the potential interfering such as metal ions and biomolecules. The Fe2O3/Bi2O3/GCE was successfully employed to simultaneously detect Cd2+ and Pb2+ from water and milk samples with good recovery.

Digital teaching in the context of Chinese universities and their impact on students for Ubiquitous Applications

The thesis aims to investigate the aspirations of Chinese educators and the use of innovations in education in the Chinese classroom due to the contradiction between the widespread encouragement of technological use in teaching and the latest research on educator software. Eight parameters such as presumed usage (PU), presumed ease of use (PEU), behavioral interpretation (BI), machine self-efficacy (MSE), software complexity (SC), ease of glass wall), and social constructivism educational values (CEVs) were introduced. Into the innovation diffusion model to investigate connections between these factors. Those would be the foundation of the technology acceptance framework. Digital teaching in the Chinese university's (DT-CU) framework is proposed in this research. Information was obtained from a Personality survey and evaluated with a conceptual model from 185 educators at five educational institutions. The findings show that the method suggested fits well. There were four values – PU, SC, and CEVs, while PEU and SC aren't the most robust determinants. In comparison, PU, CEV, and MSEs are important backgrounds for the technology usage of educator BIs. This research helped explain entrepreneurial intention hypotheses by putting the present study within the education system framework. It offered essential references for the decision formulation and personal success of educators related to technical.

The turnaround in Philippine growth: From disappointment to promising success

Philippine actual growth performance has improved during the last two decades. We obtain potential growth rate estimates for 1959-2019 using Kalman filter estimation of Okun's law. We find that potential growth has been increasing since the mid-1990s. It reached 6.1% in 2017-2019, the highest during the last six decades. As the trend labor force growth displays a downward trend, potential labor productivity growth has accounted for most of the country's potential growth rate recently. A decomposition of labor productivity growth shows that within-sector productivity growth accounted for 79% of overall labor productivity growth during 2009-2019. Most of the within-sector effect is due to manufacturing productivity growth. Analysis of the robust determinants of potential labor productivity growth using Bayesian Model Averaging indicates the relevance of proxy variables of both within-sector and reallocation effects, as well as of policy uncertainty.

The influence of maternal and paternal education on birth outcomes: an analysis of the Ottawa and Kingston (OaK) birth cohort

Background Education is considered one of the most robust determinants of health. However, it is unclear whether maternal education and paternal education have differential impacts on perinatal health outcomes. We assess maternal and paternal education differences and their association with adverse birth outcomes in a large birth cohort from Ontario, Canada. Methods The OaK Birth Cohort recruited patients from Ontario, Canada, between October 2002 and April 2009. We recruited mothers were recruited between 12 and 20 weeks’ gestation and collected both mother and infant data. The final sample size of the cohort was 8,085 participants. We use logistic regression to model the probability of preterm birth (less than 34 and 37 weeks’ gestation), small-for-gestational-age (SGA), or stillbirth as a function of maternal and paternal educational attainment. We adjust for household-level income, maternal and paternal race and ethnicity, and compare the strength of the association between maternal and paternal education on outcomes using Wald tests. Results 7,928 mother-father-offspring triads were available for the current analysis. 75% of mothers and fathers had college or university level education, and 8.7% of mothers experienced preterm delivery. Compared to mothers with college or university education, mothers with a high school education had an odds ratio of 1.37 (95% CI: 1.01–1.87) for SGA. Paternal education was not associated with infant outcomes. Comparing the odds ratios for maternal education and paternal education showed a stronger association than paternal education at the high school level for SGA birth (difference in odds ratio: 1.95, 95% CI: 1.13–3.36, p = .016) among women at least 25 years old. Conclusion Maternal education was associated with SGA, and this effect was more robust than paternal education, but both associations were weaker than previously reported.

Thermodynamic constants of formation of disulfide anion in aqueous solutions

This study is aimed at precise measurement of thermodynamic constants of disulfide (S22−) formation. It was demonstrated that these constants, K, for formation of longer polysulfides for reaction between hydrogen sulfide and orthorhombic cyclooctasulfur (α-S8) measured by independent techniques (potentiometry, spectrophotometry, chromatography) are in good agreement. For the most abundant polysulfides, S42−, S52− and S62−, the reported ranges of pK values are ≤0.72 pK units. On the other hand, pK2 values of the formation of S22− in this reaction measured by different techniques span from 11.46 to 14.43. The main difficulty in measurement of K2 is low abundance of disulfide in the solutions saturated with respect to α-S8. In this work, we applied chromatographic analysis for the samples, which are highly undersaturated with respect to α-S8. The results show that robust determination of K2 may be achieved at the molar ratio of S0 to S(II) ≤ 0.064. At these conditions the value of pK2 at 25 °C was found to be 12.77 ± 0.08. Based on this value, the standard Gibbs free energy of S22− formation was calculated. The standard enthalpy of formation and molar entropy were derived from the data obtained in experiments at the temperature range of 10 °C to 70 °C. Calculations based on these thermodynamic values show that while disulfide accounts for only a minor fraction of polysulfide zero-valent sulfur at saturation with α-S8, it can become the most abundant polysulfide at low S0 to S(II) molar ratios. In marine sediments and water columns low molar polysulfide S0 to S(II) ratio may exist in hydrogen sulfide-rich zero valent sulfur-poor systems as well as, due to kinetic constraints, in the zero valent sulfur-rich systems. Results of our work suggest that at the molar ratio of polysulfide S0 to S(II) > 0.064, the calculation of disulfide concentration should be based on concentrations of hydrogen sulfide and other polysulfides and the set of thermodynamic constants provided in this work. At the lower polysulfide S0 to S(II) ratios, the disulfide concentration should be either measured directly or calculated in case that it is below the detection limit of quantification method.

Determinants of Firm-Level Voluntary Corporate Disclosure in Emerging Markets: A Meta-Regression Analysis

The purpose of this paper is to determine which factors are most important in voluntary corporate disclosure at firm level in emerging markets. The study characteristics that cause differences in results in the original empirical studies are also examined. This study applies a meta- regression technique developed by Stanley and Jarrell (1989) to a sample of 32 empirical studies published between 2011 and 2020. The study findings reveal that the financial crisis variable, region of the study variable, and weighting of the dependent variable significantly affect study results of the original empirical researches. Moreover, the most important and robust determinants of corporate disclosure in emerging markets are board independence and foreign listing status. Study findings also indicate that firm size, which is identified by most empirical studies to be a significant and most robust determinant of corporate disclosure, to be insignificant in this meta-regression study. This study will help to resolve the ambiguity that has existed over the past decade in literature as to which factors are really important in voluntary corporate disclosure practices in emerging countries. Secondly, this study extends the literature relating to corporate disclosure practice in emerging countries.

Prevalence, overlap, and interrelationships of physical, cognitive, psychological, and social frailty among community-dwelling older people in Japan

Background The aim of this study is to explore the prevalence and overlap of physical, cognitive, psychological, and social frailty and their negative-interrelationships.Methods We conducted a survey of people aged ≥75 years in the region with the oldest population in Japan. Frailty was divided into physical, cognitive, psychological, and social frailty, which were evaluated with the Japanese version of the Cardiovascular Health Study (J-CHS) criteria, J-CHS and the Japanese version of the Montreal Cognitive Assessment, the Geriatric Depression Scale-15 and the Lubben Social Network Scale, respectively.Results Of the 268 participants (aged 81.5 ± 4.5 years), 48.1% and 8.6% had physical prefrailty and frailty; 68.3%, 13.0%, and 5.2% had mild cognitive impairment, dementia, and cognitive frailty; 25.7% and 5.2% had depressive mood and depression as psychological frailty; and 7.8% had social frailty, respectively. Path analysis showed that social frailty was associated with psychological frailty. Psychological frailty was associated with physical frailty. Physical frailty was associated with cognitive frailty. Multiple logistic regression analysis showed that independent determinants of physical robustness were female sex, age, and psychological robustness (odds ratio (OR) = 2.166, 0.831, 3.625, respectively). Determinants of cognitive robustness were age and psychological robustness (OR = 0.837, 7.079). Determinants of psychological robustness were physical, cognitive, and social robustness (OR = 3.759, 6.829, 5.037), and the determinant of social robustness was psychological robustness (OR = 4.489), respectively.Conclusions We demonstrated the prevalence, overlap, and interrelationships of different types of frailty and clarified the factors that may help to reduce frailty.

Conservatism, social isolation and political context: Why East Europeans would leave the EU in Exit referendums

The British decision to leave the European Union after the 2016 referendum raises questions about who could be next. This article analyzes why citizens in East European Member States would vote to leave the European Union in the event of further referendums. It proposes an analytical framework that seeks to explain this strong form of Euroscepticism through four variables that are rarely linked to the European Union: political apathy and alienation, dissatisfaction with domestic democracy and economy, conservative values, and social isolation. We use individual-level data from the 2018 wave of the European Social Survey to show that citizens’ conservative attitudes and social isolation are robust determinants of a potential European Union exit vote in Eastern Europe. We also identify several country-specific causes, which means that the European Union faces particular challenges across political settings.

The accuracy and robustness of plasma biomarker models for amyloid PET positivity

BackgroundPlasma biomarkers for Alzheimer’s disease (AD) have broad potential as screening tools in primary care and disease-modifying trials. Detecting elevated amyloid-β (Aβ) pathology to support trial recruitment or initiating Aβ-targeting treatments would be of critical value. In this study, we aimed to examine the robustness of plasma biomarkers to detect elevated Aβ pathology at different stages of the AD continuum. Beyond determining the best biomarker—or biomarker combination—for detecting this outcome, we also simulated increases in inter-assay coefficient of variability (CV) to account for external factors not considered by intra-assay variability. With this, we aimed to determine whether plasma biomarkers would maintain their accuracy if applied in a setting which anticipates higher variability (i.e., clinical routine).MethodsWe included 118 participants (cognitively unimpaired [CU, n = 50], cognitively impaired [CI, n = 68]) from the ADNI study with a full plasma biomarker profile (Aβ42/40, GFAP, p-tau181, NfL) and matched amyloid imaging. Initially, we investigated how simulated CV variations impacted single-biomarker discriminative performance of amyloid status. Then, we evaluated the predictive performance of models containing different biomarker combinations, based both on original and simulated measurements. Plasma Aβ42/40 was represented by both immunoprecipitation mass spectrometry (IP-MS) and single molecule array (Simoa) methods in separate analyses. Model selection was based on a decision tree which incorporated Akaike information criterion value, likelihood ratio tests between the best-fitting models and, finally, and Schwartz’s Bayesian information criterion.ResultsIncreasing variation greatly impacted the performance of plasma Aβ42/40 in discriminating Aβ status. In contrast, the performance of plasma GFAP and p-tau181 remained stable with variations >20%. When biomarker models were compared, the models “AG” (Aβ42/40 + GFAP; AUC = 86.5), “A” (Aβ42/40; AUC = 82.3), and “AGP” (Aβ42/40 + GFAP + p-tau181; AUC = 93.5) were superior in determining Aβ burden in all participants, within-CU, and within-CI groups, respectively. In the robustness analyses, when repeating model selection based on simulated measurements, models including IP-MS Aβ42/40 were also most often selected. Simoa Aβ42/40 did not contribute to any selected model when used as an immunoanalytical alternative to IP-MS Aβ42/40.ConclusionsPlasma Aβ42/40, as quantified by IP-MS, shows high performance in determining Aβ positivity at all stages of the AD continuum, with GFAP and p-tau181 further contributing at CI stage. However, between-assay variations greatly impacted the performance of Aβ42/40 but not that of GFAP and p-tau181. Therefore, when dealing with between-assay CVs that exceed 5%, plasma GFAP and p-tau181 should be considered for a more robust determination of Aβ burden in CU and CI participants, respectively.

The impact of state capacity on the cross-country variations in COVID-19 vaccination rates.

The initial period of vaccination shows strong heterogeneity between countries’ vaccinations rollout, both in the terms of the start of the vaccination process and in the dynamics of the number of people that are vaccinated. A predominant thesis for this observation is that a key determinant of the swift and extensive vaccine rollout is state capacity. Here, we utilize two measures that quantify different aspects of the state capacity: (i) the external capacity (measured through the soft power of the country) and (ii) the internal capacity (measured via the country’s government effectiveness) and provide an empirical test for their relationship with the coronavirus vaccination outcome in the initial period (up to 31st March 2021). By using data on 128 countries and a two-step Heckman approach, we find that the soft power is a robust determinant of whether a country has started with the vaccination process. In addition, the government effectiveness is a key factor that determines vaccine roll-out. Altogether, our findings are in line with the hypothesis that state capacity determines the observed heterogeneity between countries in the initial period of COVID-19 vaccines rollout. As such, they are a stark reminder for the need for transparent and fair global response regarding fair and equitable availability of vaccines to every country.

Absolute SESAM characterization via polarization-resolved non-collinear equivalent time sampling

Semiconductor saturable absorber mirrors (SESAMs) have enabled a wide variety of modelocked laser systems, which makes measuring their nonlinear properties an important step in laser design. Here, we demonstrate complete characterization of SESAMs using an equivalent time sampling apparatus. The light source is a free-running dual-comb laser, which produces a pair of sub-150-fs modelocked laser outputs at 1051 nm from a single cavity. The average pulse repetition rate is 80.1 MHz, and the full time window is scanned at 240 Hz. Cross-correlation between the beams is used to calibrate the time axis of the measurements, and we use a non-collinear pump-probe geometry on the sample. The measurements enable fast and robust determination of all the nonlinear reflectivity and recovery time parameters of the devices from a single setup, and show good agreement with conventional nonlinear reflectivity measurements. We compare measurements to a rate equation model, showing good agreement up to high pulse fluence values and revealing that the samples tested exhibit a slightly slower recovery at higher fluence values. Lastly, we examine the polarization dependence of the reflectivity, revealing a reduced rollover if cross-polarized beams are used or if the sample is oriented optimally around the beam axis.

The Devil is in the Details: On the Robust Determinants of Development Aid in G5 Sahel Countries

The Devil is in the Details: On the Robust Determinants of Development Aid in G5 Sahel Countries

Analysis insights for three FRET pairs of chemically unlinked two-molecule FRET cytometry.

Förster resonance energy transfer (FRET) is the direct energy exchange between two-component fluorescent molecules. FRET methods utilize chemically linked molecules or unlinked fluorescent molecules such as fluoresscent protein-protein interactions. FRET is therefore a powerful indicator of molecular proximity, but standardized determination of FRET efficiency is challenged when investigating natural (chemically unlinked) interactions. In this paper, we have examined the interactions of tumor necrosis factor receptor-1 (TNFR1) molecules expressed as recombinant C-terminal fusion proteins of cyan, yellow, or red fluorescent protein (-CFP, -YFP, or -RFP) to evaluate two-molecule chemically unlinked FRET by flow cytometry. We demonstrate three independent FRET pairs of TNFR1 CFP→YFP (FRET-1), YFP→RFP (FRET-2) and CFP→RFP (FRET-3), by comparing TNFR1+TNFR1 with non-interacting TNFR1+CD27 proteins, on both LSR-II and Fortessa X-20 cytometers. We describe genuine FRET activities reflecting TNFR1 homotypic interactions. The FRET events can be visualized during sample acquisition via the use of "spiked" FRET donor cells, together with TNFR1+TNFR1 co-transfected cells, as FRET channel mean fluorescence intensity (MFI) overlays. FRET events can also be indicated by comparing concatenated files of cells expressing either FRET positive events (TNFR1+TNFR1) or FRET negative events (TNFR1+CD27) to generate single-cell scatter plots showing loss of FRET donor brightness. Robust determination of FRET efficiency is then confirmed at the single-cell level by applying matrix calculations based on the measurements of FRET, using donor, acceptor, and FRET fluorescent intensities (I), detector channel emission coefficient (S), fluorescent protein extinction coefficients (ε) and the α factor. In this TNFR1-based system the mean CFP→YFP FRET-1 efficiency is 0.43 (LSR-II) and 0.41 (Fortessa X-20), the mean YFP→RFP FRET-2 efficiency is 0.30 (LSR-II) and 0.29 (Fortessa X-20), and the mean CFP→RFP FRET-3 efficiency is 0.56 (LSR-II) and 0.54 (Fortessa X-20). This study also embraces multi-dimensional clustering using t-SNE, Fit-SNE, UMAP, Tri-Map and PaCMAP to further demonstrate FRET. These approaches establish a robust system for standardized detection of chemically unlinked TNFR1 homotypic interactions with three individual FRET pairs.

SME’s Cost of Debt: A Meta-Analysis of Borrower, Creditor and Financial Statement Verification Attributes

Private firm financing, given the far-reaching importance of non-publicly traded companies for global output and employment, is still a relatively underexplored area. Since the seminal work of Petersen and Rajan (1994), only a small branch of research into private firms’ cost of debt has been established. We aggregate the full body of this research that has empirically investigated antecedents of private firms’ cost of debt in a meta-analysis. The foremost antecedents can be categorized into either borrower, creditor or financial statement verification attributes. Our results reveal a set of 11 highly significant and robust determinants.

"Bootstraping" metoda bazirana na minimalnoj kovarijansnoj determinanti za procenu podataka o dolascima putnika u vazdušnom saobraćaju

Air travel management is a case-special process since it includes different types of uncertainties such as ungovernable passenger mobility, variable costs as well as extraordinary restrictions like the Covid-19 pandemic. Therefore, the use of robust and reproducible statistical evaluations under uncertainty is required. The cornerstone of this study is the adaptation of bootstrapping and the robust Minimum Covariance Determinant (MCD)-based parameter estimation under a heterogeneous process. In addition, the study includes a novel bootstrapping regression implementation. The methodological developments have been tested by Serbia's air transport data. The results showed that combining robust estimator and bootstrapping provides some advantages for determining outliers and also making advanced diagnostics. Thus, a state-of-the-art approach based on accuracy, reproducibility, and transparency has been introduced and its usability in the air travel mobility process has been exhibited.

A Panel of Real-Time PCR Assays for the Direct Detection of All of the Xylella fastidiosa Subspecies.

The bacterial plant pathogen Xylella fastidiosa causes disease in hundreds of plant species worldwide including many crops, and as such accurate determination of the subspecies of the bacteria is vital to control, containment, and eradication measures. Conventional methods to determine the subspecies of X. fastidiosa rely on time consuming multilocus sequence typing (MLST), a laborious multistage process. This chapter provides a rapid alternative to MLST utilizing real-time PCR assays to provide highly specific and sensitive detection of the pathogen subspecies. Here we describe the methodology for sampling plant material, performing the DNA extraction and undertaking the real-time PCR assays. This method allows straightforward, robust, reliable, high-throughput, and rapid determination of the X. fastidiosa subspecies.

Water-soluble pillar[5]arene-modified graphdiyne functional material and its application towards ultrasensitive and robust electrochemical methylamphetamine determination

Schematic illustration of the application of the novel material WP5–GDY/GCE for the electrochemical sensing of methylamphetamine (MA).

How Economic, Political and Institutional Factors Influence the Choice of Exchange Rate Regimes? New Evidence from Selected Countries of the MENA Region

In this paper, we investigate how economic, political, and institutional factors affect the choice of exchange rate regimes using data on eight Middle East and North Africa (MENA) countries over the 1984-2016 period. Specifically, we run random-effects ordered probit regressions of the likelihood of exchange rate regimes on the potential determinants of exchange rate regimes. Three important findings emerge from the analysis. The first finding is that political and institutional factors play an important role in determining the exchange rate regime in MENA countries, where a democratic political regime and a low level of corruption increase the probability of opting for a fixed regime, while strong governments, political stability (such as less internal conflicts and more government stability), more law and order enforcement, and a left-wing government decrease the probability of opting for a fixed regime. The second finding is that bureaucracy, independent central banks, elections, terms of trade, and monetary independence have no effect on the choice of exchange rate regimes. The third finding is that financial development is not a robust determinant of the choice of exchange rate regimes. Our results still hold when considering alternative specifications, and they have important implications for policymakers in MENA countries