Tag: statistics

FASEB Bioadv. 2023 Sep 8;5(10):412-426. doi: 10.1096/fba.2023-00070. eCollection 2023 Oct.

ABSTRACT

Early detection and recurrence prediction are challenging in triple-negative breast cancer (TNBC) patients. We aimed to develop mitochondrial DNA (mtDNA)-based liquid biomarkers to improve TNBC management. Mitochondrial genome (MG) enrichment and next-generation sequencing mapped the entire MG in 73 samples (64 tissues and 9 extracellular vesicles [EV] samples) from 32 metastatic TNBCs. We measured mtDNA and cardiolipin (CL) contents, NDUFB8, and SDHB protein expression in tumors and in corresponding circulating EVs. We identified 168 nonsynonymous mtDNA mutations, with 73% (123/186) coding and 27% (45/168) noncoding in nature. Twenty percent of mutations were nucleotide transversions. Respiratory complex I (RCI) was the key target, which harbored 44% (74/168) of the overall mtDNA mutations. A panel of 11 hotspot mtDNA mutations was identified among 19%-38% TNBCs, which were detectable in the serum-derived EVs with 82% specificity. Overall, 38% of the metastatic tumor-signature mtDNA mutations were traceable in the EVs. An appreciable number of mtDNA mutations were homoplasmic (18%, 31/168), novel (14%, 23/168), and potentially pathogenic (9%, 15/168). The overall and RCI-specific mtDNA mutational load was higher in women with African compared to European ancestry accompanied by an exclusive abundance of respiratory complex (RC) protein NDUFB8 (RCI) and SDHB (RCII) therein. Increased mtDNA (p < 0.0001) content was recorded in both tumors and EVs along with an abundance of CL (p = 0.0001) content in the EVs. Aggressive tumor-signature mtDNA mutation detection and measurement of mtDNA and CL contents in the EVs bear the potential to formulate noninvasive early detection and recurrence prediction strategies.

PMID:37810173 | PMC:PMC10551276 | DOI:10.1096/fba.2023-00070

Heliyon. 2023 Sep 7;9(9):e19848. doi: 10.1016/j.heliyon.2023.e19848. eCollection 2023 Sep.

ABSTRACT

A non-linear system of differential equations was used to explain the spread of the COVID-19 virus and a SEIQR model was developed and tested to provide insights into the spread of the pandemic. This article, which is related to the aforementioned work as well as other work covering variations of SIR models, Hermite Wavelets Transform, and also the Generalized Compartmental COVID-19 model, we develop a mathematical control model and apply it to represent optimal vaccination strategy against COVID-19 using Pontryagin’s Maximum Principle and also factoring in the effect of facemasks on the spread of the virus. As background work, we analyze the mathematical epidemiology model with the facemask effect on both reproduction number and stability, we also analyze the difference between confirmed COVID-19 cases of the Quarantine class and anonymous cases of the Infectious class that is expected to recover. We also apply control theory to mine insights for effective virus spread prevention strategies. Our models are validated using Matlab mathematical model validation tools. Statistical tests against data from Jordan are used to validate our work including the modeling of the relation between the facemask effect and COVID-19 spread. Furthermore, the relation between control measure ξ, cost, and Infected cases is also studied.

PMID:37810168 | PMC:PMC10559238 | DOI:10.1016/j.heliyon.2023.e19848

Heliyon. 2023 Sep 1;9(9):e19729. doi: 10.1016/j.heliyon.2023.e19729. eCollection 2023 Sep.

ABSTRACT

Forecasts for key macroeconomic variables are almost always made simultaneously by the same organizations, presented together, and used together in policy analyses and decision-makings. It is therefore important to know whether the forecasters are skillful enough to forecast the future values of those variables. Here a method for joint evaluation of skill in directional forecasts of multiple variables is introduced. The method is simple to use and does not rely on complicated assumptions required by the conventional statistical methods for measuring accuracy of directional forecast. The data on GDP growth and inflation forecasts of three organizations from Thailand, namely, the Bank of Thailand, the Fiscal Policy Office, and the Office of the National Economic and Social Development Council as well as the actual data on GDP growth and inflation of Thailand between 2001 and 2021 are employed in order to demonstrate how the method could be used to evaluate the skills of forecasters in practice. The overall results indicate that these three organizations are somewhat skillful in forecasting the direction-of-changes of GDP growth and inflation when no band and a band of ± 1 standard deviation of the forecasted outcome are considered. However, when a band of ± 0.5% of the forecasted outcome is introduced, the skills in forecasting the direction-of-changes of GDP growth and inflation of these three organizations are, at best, little better than intelligent guess work.

PMID:37810150 | PMC:PMC10558991 | DOI:10.1016/j.heliyon.2023.e19729

Heliyon. 2023 Aug 25;9(9):e19533. doi: 10.1016/j.heliyon.2023.e19533. eCollection 2023 Sep.

ABSTRACT

The literature on entrepreneurship and technology transfer highlights several factors that impact the creation of university Spin-Offs. However, there is a limited body of research that specifically explores the impact of university-industry collaborations on the performance creation of these spinoffs. This study aims to fill this gap by examining the effects of university-industry collaborations on the creation of Spin-Offs from two perspectives: the number of university collaborations with different companies and the number of previous collaborations between the same university-industry dyad. The research employs joint patents as a source to measure the university-industry collaborations and statistical methods to empirically examine the impact of these collaborations on Spin-Off creation. The study is based on data from 108 universities between the years 2014 and 2017. The findings of this study reveal that both the number of collaborations and specially the presence of previous collaborations between the university and industry have a positive effect on the creation of Spin-Offs. These results suggest that universities and companies should consider these findings when formulating their strategies or policies for technology transfer and innovation management by encouraging university-industry collaborations.

PMID:37810148 | PMC:PMC10558740 | DOI:10.1016/j.heliyon.2023.e19533

Heliyon. 2023 Aug 29;9(9):e19378. doi: 10.1016/j.heliyon.2023.e19378. eCollection 2023 Sep.

ABSTRACT

Empirical observation, controlled experiments, and pedestrian dynamics models are used to research pedestrian movement. These studies rely on single-file fundamental diagrams. Experiments were conducted in Ghana, and African students in China and Germany undertook experiments (Seyfried et al., 2005) [1]. Different groups of pedestrians were tested, and then told the entrance group conducted three corridor rotations. A t-test and z-test were employed to compare all measurement findings statistically. The study found significant spatial and cultural implications on single-file pedestrian travel. African pupils in China have an R² of 0.63 (63%), while Ghanaians have an R² of 0.77 (77%). Both groups are African, suggesting that location influences single-file pedestrian principles. According to a comparable study, Indian and German pedestrian fundamental diagrams [2,3], German and Brazil [4,5] show considerable variances. This research examines whether locations and culture affect single-file pedestrian travel.

PMID:37810143 | PMC:PMC10558330 | DOI:10.1016/j.heliyon.2023.e19378

Heliyon. 2023 Aug 30;9(9):e19651. doi: 10.1016/j.heliyon.2023.e19651. eCollection 2023 Sep.

ABSTRACT

Spatial heterogeneity is a fundamental research topic in the field of geography, and Geodetector is a widely used tool for studying this phenomenon. To understand the research advancements and knowledge diffusion trends surrounding Geodetector, we constructed an author evolutionary tree structure fusing its 847 core citations in the Web of Science database and Geotree model for the first time. The results of our literature statistics indicated that Geodetector has garnered the attention of 3123 authors from 48 countries since its publication in the Ecological Indicators journal in 2010, who have published core papers concerning ten important topics. The majority of these studies focused on spatial heterogeneity and its influencing factors. Our analysis of Geotree data revealed a significant correlation between the publication rate of scholars in large teams and their academic activities. Our analysis of the knowledge diffusion chain shown that only 2% of the total number of authors have contributed to over 20% of the scientific collaborations and knowledge diffusion, and they were recognized as experts in Geodetector research. To provide a comprehensive reference for future scholars, we have summarized the citing countries, five classical articles, main scientific domains, and core teams of Geodetector research.

PMID:37810142 | PMC:PMC10558907 | DOI:10.1016/j.heliyon.2023.e19651

Heliyon. 2023 Sep 1;9(9):e19604. doi: 10.1016/j.heliyon.2023.e19604. eCollection 2023 Sep.

ABSTRACT

This study aims to evaluate the safety, biocompatibility, and functionality of a new accommodative intraocular lens (IOL) (LUZ, patent PCT/ES2016/070,813) after implantation in rabbit eyes. LUZ (Study) and EyeCee® plus a capsular ring (Control) were implanted in rabbits (n = 8 each) after phacoemulsification. Intraoperative follow-up, long-term clinical follow-up, and functional IOL studies were carried out periodically for up to 180 days. A macroscopic examination of the eyeballs to reveal abnormalities and determine the implant centering and a microscopic examination to semi-quantify cell and tissue response were performed. Statistical analysis of the collected data was finally achieved. During follow-up, no significant changes in the general condition nor the clinical evaluation were observed between both groups. However, Study IOL remained centered throughout the study and did not present severe complications as observed in the Control group. Functional studies did not reveal significant differences between both materials. Study showed better centering, fewer adhesions, and maintenance of an opening capsular bag compared to the Control. Local biological effects caused by Study implantation are minimal and comparable to the Control. Therefore, LUZ showed no clinical signs or histological response of adverse reaction to the implanted material, according to UNE-EN ISO 11979-5 and 10993-6. Functionality must be confirmed in another animal species with greater lens accommodation capacity than the rabbit. LUZ keeps the capsular bag open, favoring its centering and avoiding fibrosis and adherence to the bag; this allows potential accommodation of this IOL and theoretically enables the patient to focus dynamically.

PMID:37810139 | PMC:PMC10558835 | DOI:10.1016/j.heliyon.2023.e19604

Heliyon. 2023 Sep 4;9(9):e19753. doi: 10.1016/j.heliyon.2023.e19753. eCollection 2023 Sep.

ABSTRACT

BACKGROUND: Hamstring muscle tightness contributes to disability in people with chronic low back pain (CLBP). HM stretching improves flexibility in healthy individuals, but the immediate effect of stretching is unknown in people with CLBP. Moreover, the stretching effect could be influenced by psychosocial factors.

OBJECTIVES: To evaluate the immediate effect of passive HM stretching on flexibility in people with CLBP and the relationships between psychosocial factors and change in hamstring flexibility.

DESIGN: Non-randomized, pilot trial.

METHOD: One minute of passive stretching was performed in 90 people with CLBP. Change in Active Knee Extension and Straight Leg Raise angles (digital inclinometer), and Fingertips-to-Floor distance (measuring tape) were measured before and immediately after stretching. Correlations between change in flexibility and baseline Fear-Avoidance Beliefs Questionnaire (FABQ) and Hospital Anxiety and Depression Scale (HADS) scores were analyzed.

RESULTS: Hamstring flexibility improved significantly after stretching; Active Knee Extension mean difference was 4° (95% CI, 2.4 to 5.1; p < 0.001, right ES = 0.24, left ES = 0.23); Straight Leg Raise mean difference was 7° (95% CI, 5.5 to 8.6, p < 0.001, right ES = 0.44, left ES = 0.42), Fingertips-to-Floor mean difference was 2 cm (95% CI, 1.7 to 3.0, p < 0.001, ES = 0.20). No correlation was found between improvement in any of the hamstring flexibility measurements and FABQ or HADS scores (p > 0.05).

CONCLUSIONS: Passive hamstring stretching induced an immediate, statistically significantly improvement in hamstring flexibility, but only the change in Straight Leg Raise amplitude was clinically important. Psychosocial factors were not related to improvements in flexibility after hamstring stretching.

PMID:37810115 | PMC:PMC10559058 | DOI:10.1016/j.heliyon.2023.e19753

Heliyon. 2023 Sep 6;9(9):e19899. doi: 10.1016/j.heliyon.2023.e19899. eCollection 2023 Sep.

ABSTRACT

Crop quality and productivity are the fundamental strategies of agricultural practice and technology; consequently, one of the priorities in agriculture is to be aware of new and innovative field experiments and production practices. The effectiveness of innovative practices and resources is influenced by a multitude of factors. This study aimed to propose a new quantum-based approach in agriculture using homoeopathic methodology which incorporates theories and concepts of quantum physics and employs a wave-based methodology for the functional measurement phase. A novel utilization of thermal imaging technology is suggested, wherein each pixel of the image indicates the wave parameters, frequency, or amplitude of wave, is proposed to analyse the functional information of the plant. The relationship between the new quantum-agriculture-based method and the functional characteristics of flour as measured by bio-photonic emissions was estimated, and the findings of this preliminary study on wheat flour are presented. Our preliminary results (i) confirm the superior performance of quantum agriculture (QA) based proposed soil and plant treatments, and (ii) suggest that quantitative analysis based on precise measurements of biophoton emission will provide a novel reliable tool for monitoring the quality of wheat in the future. Further investigations are required to replicate the results of this study under different environmental conditions. Additionally, incorporating comparative chemical analyses that would enhance our knowledge of the proposed agronomic practice.

PMID:37810108 | PMC:PMC10559271 | DOI:10.1016/j.heliyon.2023.e19899

Heliyon. 2023 Aug 23;9(9):e19307. doi: 10.1016/j.heliyon.2023.e19307. eCollection 2023 Sep.

ABSTRACT

Spline curves are very prominent in the mathematics due to their simple construction, accuracy of assessment and ability to approximate complicated structures into interactive curved designs. A spline is a smooth piece-wise polynomial function. The primary goal of this study is to use extended cubic B-spline (ExCuBS) functions with a new second order derivative approximation to obtain the numerical solution of the weakly singular kernel (SK) non-linear fractional partial integro-differential equation (FPIDE). The spatial and temporal fractional derivatives are discretized by ExCuBS and the Caputo finite difference scheme, respectively. The present study found that it is stable and convergent. The validity of the current approach is examined on a few test problems, and the obtained outcomes are compared with those that have previously been reported in the literature.

PMID:37810099 | PMC:PMC10558353 | DOI:10.1016/j.heliyon.2023.e19307