Statistical Certainty Research Articles

Detection and localization of changes in a panel of densities

We propose a new methodology for identifying and localizing changes in the Fréchet mean of a multivariate time series of probability densities. The functional data objects we study are random densities fs,t indexed by discrete time t and a vector component s, which can be treated as a broadly understood spatial location. Our main objective is to identify the set of components s, where a change occurs with statistical certainty. A challenge of this analysis is that the densities fs,t are not directly observable and must be estimated from sparse and potentially imbalanced data. Such setups are motivated by the analysis of two data sets that we investigate in this work. First, a hitherto unpublished large data set of Brazilian Covid infections and a second, a financial data set derived from intraday prices of U.S. Exchange Traded Funds. Chief statistical advances are the development of change point tests and estimators of components of change for multivariate time series of densities. We prove the theoretical validity of our methodology and investigate its finite sample performance in a simulation study.

Accuracy of the WatchBP Office Central as a Type 2 device for non-invasive estimation of central aortic blood pressure in children and adolescents

High blood pressure (BP) in childhood is a recognised precursor of elevated cardiovascular risk in adulthood. Brachial BP is normally used for clinical decision making, but central BP may be a better marker of pressure load on the heart. There is a paucity of validated non-invasive, automated devices for estimating central BP in children and adolescents. In this study, we compared the WatchBP Office Central (a Type 2 central pressure estimation device) against a high-fidelity micromanometer in the ascending aorta of anaesthetised patients undergoing clinically-indicated catheterisation (n = 15, age 4–16 years). As a secondary aim, central systolic BP (cSBP) was also compared to two non-invasive estimation methods in 34 awake patients undergoing routine cardiac MRI (age 10–18 years). WatchBP substantially overestimated cSBP compared to the intra-arterial gold-standard reference (26.1 ± 7.4 mmHg), and recruitment was terminated at n = 11 (included in the analysis) due to high statistical certainty that the device would not pass the validation criteria of 5±8 mmHg. WatchBP cSBP was also substantially higher than values obtained from a phase contrast MRI method (11.8 ± 7.9 mmHg) and the SphygmoCor XCEL (13.5 ± 8.9 mmHg) in the awake patient group, which translate to 21–23 mmHg on average after accounting for known/estimated biases in these non-invasive comparators. Compared with invasive central diastolic and systolic BPs, the brachial measures from WatchBP yielded errors of 0.1 ± 5.6 and 12.5 ± 6.0 mmHg respectively. We conclude that the WatchBP substantially overestimates cSBP in children and adolescents. These findings reinforce the need for central BP-measuring devices to be further developed and validated in this population.

DESCRIPTION OF SOME SOIL AGROCHEMICAL CHARACTERISTICS THROUGH PCA ANALYSIS

The study evaluated how certain agrochemical indices, used in soil characterization, were classified. The study area, where the soil samples came from, was in the "Padurea Cenad" Protected Area, Timis County, Romania. The considered agrochemical indices resulted from soil analysis for agricultural land and forest land. The agrochemical indices were represented by soil reaction (pH), the content of some macroelements (Nt, P, K, Ca, Mg), microelements (Fe, Mn, Cu, Zn), and heavy metals (Cr, Ni, Pb). The soil reaction was considered with each group of elements in the analysis. According to the PCA analysis, in the case of macroelements, pH, Nt, K, Ca were grouped in PC1, and P and Mg were grouped in PC2. In the case of microelements, pH, Mn, Zn were grouped in PC1, and Cu and Fe were grouped in PC2. In the case of heavy metals, all elements were grouped in PC1. The soil reaction (pH) showed negative action in relation to macroelements (r = -0.999), and in relation to heavy metals (r = -0.972), and positive action in relation to microelements (r = 0.847). Negative action was also recorded in the case of Ca (r = -0.970). In the case of macroelements, Mg showed a strong action (r = 0.770), and the other elements showed a very strong action (r > 0.900). In the case of microelements, pH and Fe showed a strong action (r = 0.847; r = 0.877), and the other elements showed a very strong action (r > 0.900). In the case of heavy metals, Cr showed a weak action (r = 0.576), and the other elements showed a very strong action (r > 0.900). In all three analyzed groups, the results showed statistical certainty (p < 0.001).

A Summary Prospecting of Possibilities of Providing Public Health Services at the Level of North-East Region of Romania

This paper investigates issues related to the public health system in the North-East Region of Romania, focusing on possibilities for addressing/improving specific deficiencies/difficulties. The concerned region is characterized by the highest and densest population in the country, with a significant proportion of residents in rural areas (55%) and a high level of poverty. Population health indicators are among the weakest nationally, and the healthcare infrastructure is inadequate for the population's needs, with an uneven distribution that generates significant inequalities in access to medical services in the respective counties. Starting from the (statistical) certainty that Romania ranks among EU member states with the highest avoidable mortality, the paper addresses both preventable causes through public health interventions and treatable causes through quality care. After a brief introduction, the overall state of the public health system in Romania is examined, followed by a detailed analysis of the main issue stated in the title, highlighting multiple critical aspects based on data and information from official reports of prestigious institutions. Special attention is given to specific issues in local communities related to healthcare infrastructure and the provision of medical services, as well as possible solutions offered through the implementation of the General Regional Health Services Plan 2021-2027 in the North-East Region. The paper concludes with a section of conclusions, which includes perspectives on the future development of the analyzed sector.

Determining Oral Health Status and Lifestyle related Behaviors on the Example of 149 Children Aged 7 to 12 Years Old Living in Tbilisi

The level of oral hygiene in school-aged children in different countries is primarily low. Behavioral factors are the most important contributors to this low level of hygiene. It is also important to note that identifying the specific behaviors that significantly reduce disease burden is critical. The research was provided in Tbilisi, in public schools, to evaluate Oral health indicators (OHI, DMF, def), mean value of intensity of caries in school-aged children (7 to 12 years old), the role of behavioral factors in relation to oral hygiene and carbohydrate nutrition, and the popularity and relevance of preventive measures were determined. A cross-sectional study was conducted, where 149 children aged 7 to 12 were selected by simple random sampling from Tbilisi public schools. Evaluation of DEF, def, and S-OHI indices was carried out. Based on the oral health questionnaire, children’s oral care and carbohydrate nutrition behaviors were assessed, as well as attitudes toward preventive interventions. SPSS version 23 software for statistical data processing was used for statistical analysis. On the example of 149 children in the 7-12-year-old population of Tbilisi, the simplified hygiene index is evaluated by the criterion average (1.56). Urban distribution affects the hygiene index, which is statistically significant (P=0.009). Caries intensity and hygiene index in primary and permanent dentition do not depend on gender - statistical certainty is not fixed. Caries intensity is “medium” for both permanent (3.2) and primary dentition (3.9), and the mean value of caries intensity for the whole population is 6.31, which is rated as “high.” The popularity and relevance of preventive measures are low. Lifestyle behaviors related to both oral hygiene and carbohydrate-rich diets are not consistent with the recommendations provided by the FDI to reduce caries burden.

Late Pleistocene emergence of an anthropogenic fire regime in Australia’s tropical savannahs

At the time of European arrival on the Australian continent, sophisticated Indigenous societies practiced land management across Australia’s extensive tropical savannahs. Fire was one of the main tools people used to manipulate fuel loads and connectivity to reduce uncontrolled wildfire, maintain vegetation structure and enhance biodiversity. When this alteration of a ‘natural’ fire regime to a human-dominated fire regime occurred is not known. Here we assessed fire incidence and intensity over the past 150,000 years through a continuous lacustrine record by comparing the accumulation rates of micro-charcoal and stable polycyclic aromatic hydrocarbon that form during the combustion of vegetation. We also compared grass (mainly C4) pollen as a percentage of total dryland pollen with the carbon isotope composition of the stable polycyclic aromatic hydrocarbon. We established with high statistical certainty that a change in fire regime occurred at least 11,000 years ago from less-frequent, more-intense fires to more-frequent, less-intense fires. This change marked the overprinting of a largely natural fire regime by one at least modulated by Indigenous management. Our findings demonstrate that human fire use has modified fire regimes throughout the Holocene and also show how people have managed the potential for the type of high-intensity fires that are likely to increase in the future.

Evaluación del programa juntos y su relación con el bienestar de los hogares

· Recibido: 15 de julio de 2023 · Arbitrado: 8 de agosto de 2023 · Aceptado: 10 de octubre de 2023 · Publicado: 1 de febrero de 2024 The objective of this article is to determine how the evaluation of the Juntos Program is related to the well-being of affiliated households in the district of San Martín de Pangoa, Satipo, Junín region, period 2023. It was hypothetical-deductive, applied and correlational level, the quantitative approach and the non-experimental and transversal design. The population was 2,958 benefited households for the year 2023 and the sample was 343 affiliated families. The survey was used as a technique and the questionnaire as an instrument. The results were the non-existence of a relationship between the Evaluation of the Juntos Program and Well-being in the Homes in the community of the district of San Martín de Pangoa, Satipo, due to its Sig., 0.617, this being greater than 0.005 error and a correlation coefficient of the Spearman test (rho= 0.027). Concluding that, there is statistical certainty suitable to assert that there is no relationship between the evaluation of the Juntos Program and the well-being of affiliated households.

Utilizing Massively Parallel Sequencing (MPS) of Human Leukocyte Antigen (HLA) Gene Polymorphism to Assess Relatedness in Deficiency Parentage Testing.

In the realm of DNA testing with legal implications, the reliability and precision of genetic markers play a pivotal role in confirming or negating paternity claims. This study aimed to assess the potential utility of human leukocyte antigen (HLA) gene polymorphism through massively parallel sequencing (MPS) technology as robust forensic markers for parentage testing involving genetic deficiencies. It sought to redefine the significance of HLA genes in this context. Data on autosomal short tandem repeat (aSTR) mutational events across 18 paternity cases involving 16 commonly employed microsatellite loci were presented. In instances where traditional aSTR analysis failed to establish statistical certainty, kinship determination was pursued via HLA genotyping, encompassing the amplification of 17 linked HLA loci. Within the framework of this investigation, phase-resolved genotypes for HLA genes were meticulously generated, resulting in the definition of 34 inherited HLA haplotypes. An impressive total of 274 unique HLA alleles, which were classified at either the field 3 or 4 level, were identified, including the discovery of four novel HLA alleles. Likelihood ratio (LR) values, which indicated the likelihood of the observed data under a true biological relationship versus no relationship, were subsequently calculated. The analysis of the LR values demonstrated that the HLA genes significantly enhanced kinship determination compared with the aSTR analysis. Combining LR values from aSTR markers and HLA loci yielded conclusive outcomes in duo paternity cases, showcasing the potential of HLA genes and MPS technology for deeper insights and diversity in genetic testing. Comprehensive reference databases and high-resolution HLA typing across diverse populations are essential. Reintegrating HLA alleles into forensic identification complements existing markers, creating a potent method for future forensic analysis.

Cryogenic multiplexing using selective area grown nanowires

Bottom-up grown nanomaterials play an integral role in the development of quantum technologies but are often challenging to characterise on large scales. Here, we harness selective area growth of semiconductor nanowires to demonstrate large-scale integrated circuits and characterisation of large numbers of quantum devices. The circuit consisted of 512 quantum devices embedded within multiplexer/demultiplexer pairs, incorporating thousands of interconnected selective area growth nanowires operating under deep cryogenic conditions. Multiplexers enable a range of new strategies in quantum device research and scaling by increasing the device count while limiting the number of connections between room-temperature control electronics and the cryogenic samples. As an example of this potential we perform a statistical characterization of large arrays of identical quantum dots thus establishing the feasibility of applying cross-bar gating strategies for efficient scaling of future selective area growth quantum circuits. More broadly, the ability to systematically characterise large numbers of devices provides new levels of statistical certainty to materials/device development.

MRI-based measurements of spondylolisthesis and kyphosis in degenerative cervical myelopathy

BackgroundTo provide normative data and to determine accuracy and reliability of preoperative measurements of spondylolisthesis and kyphosis on supine static magnetic resonance imaging (MRI) of patients with degenerative cervical myelopathy.MethodsT2-weighted midsagittal images of the cervical spine were in 100 cases reviewed twice by one junior observer, with an interval of 3 months, and once by a senior observer. The spondylolisthesis slip (SSlip, mm) and the modified K-line interval (mK-line INT, mm) were assessed for accuracy with the standard error of measurement (SEm) and the minimum detectable change (MDC). Intraobserver and interobserver reliability levels were determined using the intraclass correlation coefficient (ICC).ResultsThe SEm was 0.5 mm (95% CI 0.4–0.6) for spondylolisthesis and 0.6 mm (95% CI 0.5–0.7) for kyphosis. The MDC, i.e., the smallest difference between two examinations that can be detected with statistical certainty, was 1.5 mm (95% CI 1.2–1.8) for spondylolisthesis and 1.6 mm (95% CI 1.3–1.8) for kyphosis. The highest reliability levels were seen between the second observation of the junior examiner and the senior observer (ICC = 0.80 [95% CI 0.70–0.87] and ICC = 0.96 [95% CI 0.94–0.98] for SSlip and mK-line INT, respectively).ConclusionsThis study provides normative values of alignment measurements of spondylolisthesis and kyphosis in DCM patients. It further shows the importance of taking measurement errors into account when defining cut-off values for cervical deformity parameters and their potential clinical application in surgical decision-making.

Whole-brain multivariate hemodynamic deconvolution for functional MRI with stability selection

Conventionally, analysis of functional MRI (fMRI) data relies on available information about the experimental paradigm to establish hypothesized models of brain activity. However, this information can be inaccurate, incomplete or unavailable in multiple scenarios such as resting-state, naturalistic paradigms or clinical conditions. In these cases, blind estimates of neuronal-related activity can be obtained with paradigm-free analysis methods such as hemodynamic deconvolution. Yet, current formulations of the hemodynamic deconvolution problem have three important limitations: (1) their efficacy strongly depends on the appropriate selection of regularization parameters, (2) being univariate, they do not take advantage of the information present across the brain, and (3) they do not provide any measure of statistical certainty associated with each detected event. Here we propose a novel approach that addresses all these limitations. Specifically, we introduce multivariate sparse paradigm free mapping (Mv-SPFM), a novel hemodynamic deconvolution algorithm that operates at the whole brain level and adds spatial information via a mixed-norm regularization term over all voxels. Additionally, Mv-SPFM employs a stability selection procedure that removes the need to select regularization parameters and also lets us obtain an estimate of the true probability of having a neuronal-related BOLD event at each voxel and time-point based on the area under the curve (AUC) of the stability paths. Besides, we present a formulation tailored for multi-echo fMRI acquisitions (MvME-SPFM), which allows us to better isolate fluctuations of BOLD origin on the basis of their linear dependence with the echo time (TE) and to assign physiologically interpretable units (i.e., changes in the apparent transverse relaxation ΔR2∗) to the resulting deconvolved events. Remarkably, we demonstrate that Mv-SPFM achieves comparable performance even when using a single-echo formulation. We demonstrate that this algorithm outperforms existing state-of-the-art deconvolution approaches, and shows higher spatial and temporal agreement with the activation maps and BOLD signals obtained with a standard model-based linear regression approach, even at the level of individual neuronal events. Furthermore, we show that by employing stability selection, the performance of the algorithm depends less on the selection of temporal and spatial regularization parameters λ and ρ. Consequently, the proposed algorithm provides more reliable estimates of neuronal-related activity, here in terms of ΔR2∗, for the study of the dynamics of brain activity when no information about the timings of the BOLD events is available. This algorithm will be made publicly available as part of the splora Python package.

The Effect of Methane–Ammonia and Methane–Hydrogen Blends on Ignition and Light-Around in an Annular Combustor

Abstract The use of hydrogen and ammonia in gas turbines, either alone or blended with natural gas, poses various technical challenges for combustion systems, including ignition. Depending on the fuel composition, the laminar flame speed and the ratio of unburned to burned gas density (dilatation ratio) of hydrogen and ammonia flames can be well outside the range seen in natural gas flames. Previous studies in annular combustion chambers have provided evidence of the importance of these properties in determining the ignition dynamics including light-around times. So far, these studies have mostly considered hydrocarbon fuels, have been limited to only a few runs, and have not yet systematically investigated variations in the dilatation ratio and the flame speed but rather have considered them as a lumped parameter. To investigate these effects in more detail, experiments characterizing the light-around times were carried out on an atmospheric annular combustor in which the dilatation ratio and the laminar flame speed was independently varied. This was achieved by varying the equivalence ratio and employing a variety of different hydrocarbon fuels (ethylene, propane, and methane) and fuel blends of methane–ammonia and methane–hydrogen. Light-around times were evaluated from global chemiluminescence measurements obtained using an azimuthal array of photomultipliers placed round the combustor chamber as well as high speed imaging. To improve statistical certainty, more than 3000 ignition and light-around times were measured with 30 repetitions obtained for each operating condition. To provide some insight into the light-around dynamics in specific cases, 900 of the 3000 sets included high-speed OH* chemiluminescence images. Light-around times for premixed pure hydrocarbon flames showed a similar dependence on the laminar flame speed as reported in previous studies. For the range of ammonia fuel blends investigated, an increase in laminar flame speed leads to a predictable increase in the flame propagation speed, as in the case of hydrocarbon fuel. Furthermore, collapse of this dependence for all blends could be achieved when corrected for an effective Lewis number, noting that all Lewis numbers for these blends were above unity. However, for hydrogen fuel blends, a decrease in dilatation ratio was found to decrease the light-around time counter to existing experimental results on the ignition of hydrocarbon fuels for which we currently do not have an explanation.

Impact Assessment of Road Construction on Landslide Susceptibility in Mountainous Region using GIS-Based Statistical Modelling

Abstract Landslide susceptibility is crucial for effective hazard management, planning mitigation, and risk reduction strategies. The present study assessed the impact of road construction on landslide susceptibility for the Mandi district. 1723 landslides data for Mandi district was compiled from the various sources with eleven causative factors. The eleven landslide causative factors were selected from numerous hydrological, geological, and topographical factors. The landslide susceptibility analysis was carried out using three bivariate statistical models, namely, Frequency Ratio (FR), Certainty Factor (CF), and Shannon Entropy (SE). Two sets of Landslide Susceptibility Maps were generated to assess the impact of road construction and divided into five landslide susceptibility classes. The SE model had the highest prediction and validation accuracy of (83-86%). The percentage area in high and very high classes of landslide susceptibility increased by 2.67-4.17% due to road construction activities in the study area.

VARIATION OF SOME PHYSIOLOGICAL INDICES IN Tagetes erecta L. ACCORDING TO GROWTH SUBSTRATE

The study evaluated the influence of some growing substrates with variable content of compost from biodegradable waste on some physiological indices and growth parameters in the Tagetes erecta L. species. Different components were used to prepare the growth substrates, and depending on the weight of participation, the experimental variants resulted: V1 – garden soil 100%; V2 – compost 100%; V3 – compost 20% + peat 70% + vermiculite 10%; V4 – compost 30% + peat 60% + vermiculite 10%; V5 – compost 40% + peat 50% + vermiculite 10% (each variant in four repetitions). The biological material was represented by the Tagetes erecta L. species. The genotype "Tagetes erecta F1 Discovery Orange" was cultivated. Physiological indices and biometric parameters were evaluated, considered representative to quantify the plants response to growth substrates: plant height (Ph), shoots number (Sn), plant diameter (Pd) and shoots diameter (Sd). Several determinations were made during the vegetation period, at different times: April 22 (T1), May 22 (T2), June 18 (T3), July 21 (T4) and August 27 (T5). A strong, positive correlation was recorded between plant height (Ph) and shoot diameter (Sd), r=0.881***. Moderate correlations were recorded between plant height (Ph) and shoot number (Sn), r=0.715***, between plant height (Ph) and plant diameter (Pd), r=0.754***, between shoot number (Sn ) and shoot diameter (Sd), r=0.700***, and between plant diameter (Pd) and shoot diameter (Sd), r=0.781***. Weak correlation was recorded between shoot number (Sn) and plant diameter (Pd), r=0.669*** (*** p < .001). In the PCA evaluation, PC1 explained 83.581% of variance, and PC2 explained 10.035% of variance. The cluster analysis, in relation to the important parameters considered (Ph, Pd) facilitated obtaining a dendrogram of association of the variants (Coph.corr.=0.881). The dynamics of the plants main parameters (Pd, Ph) on the experimental variants in relation to time, was described by polynomial equations of the 2nd degree under differentiated conditions of statistical certainty. A variable increase (D) in the evaluated parameters (positive and negative values) was recorded in the experimental variants (V2 – V5) in relation to the control variant (V1) and the moments of determination during the study period.

Analysis of prescription eyewear for personal identification in forensic optometry

Prescription eyewear offers characteristics that describe the refractive errors associated with the wearer's visual acuity. When found at the crime scene as evidence, it can help to establish a link with the owner. Eyewear characteristics can be statistically measured, allowing for scientific validation of the evidence details beyond simply matching them to the owner. Personal effects such as clothing, hair characteristics, and appearances have, at times, immensely helped to corroborate identification characteristics. The role of eyewear for forensic identification has been unexplored; hence, it is essential to understand its potential to aid identification. The present study was done by identifying the prescription values, i.e., refractive errors of 694 volunteers, and statistically analyzing these to check their relation with sex and age. It was found that there was a significant relationship between refractive errors and age, but not sex. Eyewear can thus be used to narrow the identity, and eyewear characteristics can serve as an antemortem record for identification and comparison. Additionally, combined with another type of evidence, it provides greater statistical certainty for forensic applications.

Evaluation of the Safety of Neauvia Stimulate Injectable Product in Patients with Autoimmune Thyroid Diseases Based on Histopathological Examinations and Retrospective Analysis of Medical Records

The aim of this study was to test the effect of hyaluronic acid cross-linked with polyethylene glycol containing micronized portions of calcium hydroxyapatite (Neauvia Stimulate) on both local tissue and systemic consequences, which are crucial from the perspective of long-term safety, in patients suffering from Hashimoto’s disease. This most common autoimmune disease is a frequently mentioned contraindication to the use of fillers based on hyaluronic acid as well as biostimulants based on calcium hydroxyapatite. Broad-spectrum aspects of histopathology were analyzed to identify key features of inflammatory infiltration before the procedure and 5, 21, and 150 days after the procedure. A statistically significant effect on the reduction of the intensity of the inflammatory infiltration in the tissue in relation to the state before the procedure was demonstrated, combined with a reduction in the occurrence of both antigen-recognizing (CD4) and cytotoxic (CD8) T lymphocytes. With complete statistical certainty, it was demonstrated that the treatment with Neauvia Stimulate had no effect on the levels of these antibodies. All this corresponds with the risk analysis that showed no alarming symptoms during the time of observation. The choice of hyaluronic acid fillers cross-linked with polyethylene glycol should be considered justified and safe in the case of patients suffering from Hashimoto’s disease.

Nafion-Pt IPMC electroactive behavior changes in response to environmental nonequilibrium conditions

Electroactive polymers (EAPs) continue to gain attention for their potential to offer unique and versatile solutions in the soft robotic and flexible electronic industries. Ionic polymer-metal composites (IPMCs) are a class of ionic-type EAPs which can be configured as capacitor actuators with very low voltage requirements (⩽5 V AC or DC). Their compact, portable, and lightweight properties, coupled with a biomimetic bending actuation response make them ideal for human-machine integrated technologies such as medical implants, active skins, and artificial muscles. This work tested the IPMC’s actuation and electrical response in varying saturation conditions (70% RH, 85% RH, 95% RH, and DI water liquid immersion) and voltage application schemes (direct current voltage (DCV) cycled, continuously applied, and relaxation responses upon voltage removal). This information was then used to establish actuation and back-relaxation response patterns through repetitive testing for statistical certainty. These demonstrated maximized actuation in water vapor conditions where the IPMC’s dielectric permittivity is maximized (), and the dissipation factor is minimized (). The response trends in vapor conditions are gradual but yield larger actuation ranges with increasing hydration. Liquid immersion restricts the IPMC’s range of motion but produces a sharper response pattern. These trends were validated against previously published IPMC actuator models. All of this creates a more pragmatic perspective on the potential of this technology which aids in the advancement of this material’s evolution towards viable real-world application configurations which capitalize on the material’s natural responses.

Single-cell transcriptome sequencing allows genetic separation, characterization and identification of individuals in multi-person biological mixtures

Identifying individuals from biological mixtures to which they contributed is highly relevant in crime scene investigation and various biomedical research fields, but despite previous attempts, remains nearly impossible. Here we investigated the potential of using single-cell transcriptome sequencing (scRNA-seq), coupled with a dedicated bioinformatics pipeline (De-goulash), to solve this long-standing problem. We developed a novel approach and tested it with scRNA-seq data that we de-novo generated from multi-person blood mixtures, and also in-silico mixtures we assembled from public single individual scRNA-seq datasets, involving different numbers, ratios, and bio-geographic ancestries of contributors. For all 2 up to 9-person balanced and imbalanced blood mixtures with ratios up to 1:60, we achieved a clear single-cell separation according to the contributing individuals. For all separated mixture contributors, sex and bio-geographic ancestry (maternal, paternal, and bi-parental) were correctly determined. All separated contributors were correctly individually identified with court-acceptable statistical certainty using de-novo generated whole exome sequencing reference data. In this proof-of-concept study, we demonstrate the feasibility of single-cell approaches to deconvolute biological mixtures and subsequently genetically characterise, and individually identify the separated mixture contributors. With further optimisation and implementation, this approach may eventually allow moving to challenging biological mixtures, including those found at crime scenes.

Studying and enhancing the methods for distance teaching of computer science in Kazakh secondary school students during the pandemic

Introduction. In 2020, the first two weeks of the enforced transformation of all the levels of school education, which was initiated as one of the measures against the Coronavirus disease (COVID-19), revealed a range of issues hampering the appropriate distance education. The absence of the methodological basis for conducting online classes in the Kazakh pedagogical community defined the need to study and enhance forms and technologies that would be efficient to use to interact with students during the transition of the national education system to distance education.Aim. The aim of this research lies in defining efficient methods for distance teaching of computer science in the Kazakh secondary school students in terms of ensuring the maintenance of the quality of knowledge and the academic progress of students at the sufficient level corresponding to that of the traditional in-person education.Methodology and research methods. A total of five educators and 320 students of three Kazakh schools took part in the study. At the moment of the experiment, the students were aged 12 to 18 years old. The participants were divided into seven groups according to the educational level (5th–11th forms) in order to make it more convenient to trace qualitative changes in the academic progress depending on the selected method for distance teaching of computer science. The authors conducted three control evaluations of the quality of knowledge in each of the 320 participants. The t-test for unpaired samples for every group was conducted to prove the statistical certainty of the calculated average reference values, which were required to confirm the viability of the conducted research. The analysis of the data obtained at the concluding stage of the experiment allowed to compare them with the reference values calculated at the preliminary stage of the research in question. For the comparison, The authors applied the Mann–Whitney U test for independent samples.Results. The preliminary analysis of the quality of knowledge related to the discipline of computer science in the participants revealed generally high and average level of both acquisition of theoretical information and development of the subject-related skills, which was registered based of the results of in-person education. The leading experience of the specialists composing the authors’ initiative research group allowed developing a structural scheme for an online lesson. The lessons applying this scheme were conducted up to the end of the academic quarter. By conducting the Mann–Whitney U test, we discovered that the obtained average values of the quality of teaching computer science to the participants statistically increased (I group – Uemp = 6.49 (p ≤ 0.05), II group – Uemp = 7.46 (p ≤ 0.05), III group – Uemp = 6.05 (p ≤ 0.01), IV group – Uemp = 6.71 (p ≤ 0.05), V group – Uemp = 6.91 (p ≤ 0.01), VI group – Uemp = 6.65 (p ≤ 0.05), VII group – Uemp = 6.21 (p ≤ 0.05)). Despite temporary fall in the efficiency of teaching computer science registered during the transition to the distance model, it was managed to achieve the level of academic progress and acquisition of knowledge corresponding to that of in-person education.Scientific novelty. TThe significance of the collected and analysed data was statistically proved. The data confirmed the efficiency of the use of defined and adapted approaches and teaching techniques, which were able to compensate the absence of traditional in-person lessons, while preventing the fall in the academic progress and the quality of knowledge in students.Practical significance. The obtained results evidence the success of the arrangements aimed at the enhancement of the methods for distance teaching of computer science in the Kazakh secondary school students during the transition to distance education enforced due to the pandemic.

Modifications of Kompetitive Allele-Specific PCR (KASP) Genotyping for Detection of Rare Alleles.

KASP is commonly used to genotype bi-allelic SNPs and In/Dels, and the standard protocol works well when both alleles are nearly equally prevalent in the DNA template. To detect rare alleles in bulked samples or to distinguish more than three genotypes, such as tri-allelic loci or mutations across orthologous genes in polyploids, adjustments to the protocol and/or data analysis are required. In this chapter, we present modified protocols for these non-traditional applications, including reaction conditions that enhance the fluorophore signal from rare alleles, resulting in increased KASP assay sensitivity. We also describe alternative KASP data analysis approaches that increase statistical certainty of genotyping calls. Furthermore, this increased assay sensitivity enables high-throughput genotyping using KASP, as samples can be pooled and tested in a single reaction. For example, rare alleles can be detected in mixed seed pools when present in ratios as low as 1 in 200. The assay modifications presented here expand the options available for complex genotyping, and retain KASP's advantages of being cheap, fast, and accurate.