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Pb:Sn Ratio-Driven Polytypism and Band Modulation in Photoresponsive Hexagonal Perovskitoids
Prevalence and correlates of contraceptive use among adolescent mothers: Results from a cross-sectional survey in Ouagadougou, Burkina Faso, and Blantyre, Malawi
Background Adolescent motherhood remains a pressing public health challenge in sub-Saharan Africa, where repeat pregnancies exacerbate the risks of maternal morbidity, disrupted education, and entrenched economic vulnerability. Contraceptive use among sexually active adolescent mothers offers a critical pathway to mitigate these adverse outcomes, yet empirical evidence on prevalence, determinants, and barriers to contraceptive uptake within this population remains strikingly limited across the region. Our study examines contraceptive use, its correlates, and reasons for non-use of contraception among adolescent mothers (aged 12–19) in Ouagadougou, Burkina Faso and Blantyre, Malawi. Methodology The data analyzed for this study were part of a larger cross-sectional survey on the lived experiences of pregnant and parenting girls. For this study, we limited our analysis to 628 (Ouagadougou) and 500 (Blantyre) adolescent mothers who were neither pregnant nor trying to get pregnant. We randomly selected urban and rural enumeration areas (EAs) in the study settings, conducted household listing, and identified eligible participants whom we interviewed. We used interviewer-administered questionnaires to obtain information on contraceptive awareness, use, and reason for non-use, and analyzed the data using descriptive and inferential statistics. Results Knowledge of contraceptive methods is nearly universal among adolescent mothers, and the contraceptive use prevalence was higher than the national average in both study settings. Single adolescent mothers were significantly less likely to be currently using any contraceptive methods (AOR: 0.75; 95% CI: 0.61–0.93 in Burkina Faso; AOR: 0.60; 95% CI: 0.50–0.71 in Malawi) or any modern methods (AOR: 0.66; 95% CI: 0.49–0.90 in Burkina Faso; AOR: 0.55; 95% CI: 0.46–0.66 in Malawi) compared to their married counterparts in both countries. Adolescent mothers aged 19 were more likely to be current users of any contraceptives compared to those aged 16 or younger in Burkina Faso (AOR: 1.55; 95% CI: 1.07–2.26) and were also more likely to have ever used any methods in Malawi (AOR: 1.28; 95% CI: 1.07–1.53). Infrequent sex (Malawi, 64.9%; Burkina |Faso, 36.6%) was the main reason for contraceptive non-use, though fear of side-effects (17.7%) and religious prohibition (16.6%) also stood out. Conclusion A substantial proportion of adolescent mothers, especially single and younger adolescents, are not using any contraceptive methods or relying on less effective methods. These results underscore the need for more interventions targeting adolescent mothers with accurate information on contraceptive methods. These interventions should address the religious objection to contraceptives in Burkina Faso and infrequent sex in Malawi.
The Isopropylstilbene Precursor Cinnamic Acid Inhibits Anthraquinone Pigment Production by Targeting AntI
Clinical efficacy of different therapeutic options for knee osteoarthritis: A network meta-analysis based on randomized clinical trials
Objective To assess and compare the clinical efficacy of various therapeutic options in treating patients with knee osteoarthritis (KOA). Methods We performed a comprehensive search of PubMed, Embase, OVID, Cochrane Library and Web of Science databases from their inception to December 10th, 2023, identifying randomized controlled trials (RCTs) examining the effects of therapeutic options on KOA. Two researchers independently performed literature screening, data extraction, data collection and organization, and quality assessment. The data obtained were subjected to statistical analysis and graphical representation using Stata 17.0 software. Results A total of 139 RCTs encompassing 9644 KOA patients and involving 12 therapeutic options were included. These interventions were low level laser therapy (LLLT), high intensity laser therapy (HILT), transcutaneous electrical nerve stimulation (TENS), interferential current (IFC), short wave diathermy, ultrasound, lateral wedged insole, knee brace, exercise, hydrotherapy, kinesio taping (KT) and extracorporeal shock wave therapy (ESWT). Regarding the WOMAC pain score, knee brace was determined to be the most likely to yield the best results, followed by exercise and HILT, ultrasound was worst intervention. In terms of WOMAC function score, knee brace emerged as the technique with the highest likelihood of being optimal, followed in sequence by hydrotherapy and ESWT, ultrasound was worst intervention. Knee brace ranked highest in effectiveness concerning the WOMAC stiffness score, followed by exercise and hydrotherapy. For the total WOMAC score, hydrotherapy demonstrated the highest probability of being the best technique, followed by exercise and HILT, short wave diathermy was worst intervention. In addressing VAS-rest, hydrotherapy exhibited the greatest likelihood of being the optimum technique, followed by HILT and LLLT. In terms of VAS-activity, knee brace had the highest probability of being the best technique, followed by LLLT and exercise, ultrasound was worst intervention. Overall, based on the results obtained from the SUCRA for all outcomes, knee brace had the highest probability of being the best technique, followed by hydrotherapy and exercise. Conclusion The findings suggest that knee brace may be the most recommended therapeutic option for the knee osteoarthritis, followed by hydrotherapy and exercise.
Oxygen-Vacancies-Ordering Triggered Large Ferroelectric Polarization in CaTiO<sub>3</sub> Thin Films
Kendallknight: An R package for efficient implementation of Kendall’s correlation coefficient computation
The kendallknight package introduces an efficient implementation of Kendall’s correlation coefficient computation, significantly improving the processing time for large datasets without sacrificing accuracy. The kendallknight package, following Knight (1966) and posterior literature, reduces the time complexity resulting in drastic reductions in computation time, transforming operations that would take minutes or hours into milliseconds or minutes, while maintaining precision and correctly handling edge cases and errors. The package is particularly advantageous in econometric and statistical contexts where rapid and accurate calculation of Kendall’s correlation coefficient is desirable. Benchmarks demonstrate substantial performance gains over the Base R implementation, especially for large datasets.
Transformation of Pyridines into 2D and 3D Fused Bicyclic Heterocycles
Heat loss evaluation for heating building envelope based on relevance vector machine
Due to the influence of many factors, there is no reasonable evaluation method for the heat loss evaluation of the envelope, which leads to the deviation of the evaluation results of building energy consumption. By comparing different regression analysis models and considering the heat transfer characteristics of the envelope and heat loss evaluation needs, the dynamic reference value of heat loss evaluation “temperature baseline” which meets different energy saving standards is established. The evaluation method of instantaneous heat loss of the envelope is proposed and the heat loss is studied. The results showed that the performance indexes of relevance vector machine (RVM) regression model was superior to the other two regression models(response surface methodology (RSM), support vector machine (SVM). Based on the RVM regression model, the dynamic prediction model of “temperature baseline” was established by combining numerical simulation with regression analysis. Taking a residential building as an example, the envelope temperature baselines meeting the energy saving standard of 75% and 50% were obtained by using the prediction model, the temperature baselines of walls and windows that save 75% energy were −0.6°C and 1.9 °C respectively, and those that save 50% energy were 1.2°C and 4.5°C. The infrared image and heat loss evaluation method found that 87% of the points exceeded the temperature baseline by more than 2°C, and the total heat loss of the wall with an area of 13m2 was 471W. The heat loss evaluation method based on RVM proposed in this paper can objectively evaluate the heat loss of building.
Homochiral Single Crystals of Helical Polymer Nanotubes: Synthesis and Application
Performance of teenaged action video game players on the Developmental Eye Movement and King-Devick tests
Action video game (AVG) players have been reported to demonstrate improved perceptual, cognitive, and motor skills, as well as enhanced eye movements such as saccade latency and accuracy. This study examined if these improvements are also observed in two common clinical eye movement assessments, the Developmental Eye Movement (DEM) and King–Devick tests. Ninth and tenth graders (15–16 years old) without learning disabilities or oculomotor dysfunctions, and who do not regularly play ball sports were tested in the DEM and King–Devick tests in random order. Those playing AVG ≥ 5 hours per week were included in the AVG group, and those playing ≤ 1 h per week were included in the non-video game group (NVG). Participants were asked to read quickly while reading speed and errors were recorded. Two DEM subtests were read vertically and one subtest was read from left to right. All King–Devick subtests were read from left to right. Forty participants (20 AVG, 20 NVG, 15 girls, mean age: 15.7 ± 0.1 years) were included. AVG players were significantly faster in their horizontal DEM times (AVG: 26 ± 5, NVG: 34 ± 7 sec, p < 0.001) and King–Devick times (AVG: 14 ± 2, NVG: 16 ± 4 sec, p = 0.034), but not in their vertical DEM times (AVG: 26 ± 3, NVG: 28 ± 5 sec p = 0.063). King-Devick and horizontal DEM times were significantly correlated for the entire sample (p < 0.01). Teenagers who regularly played AVGs performed better on the DEM and King–Devick tests, indicating that regularly playing this genre of AVGs may enhance oculomotor skills and visual processing speed. Clinicians should take this into account when interpreting results of these clinical tests.
Development of Sclareol- and Sclareolide-Based Chemoenzymatic Approaches to Ring Intact and <i>Seco</i> Limonoids
Morphological traits and machine learning for genetic lineage prediction of two reef-building corals
Integrating multiple lines of evidence that support molecular taxonomy analysis has proven to be a robust method for species delimitation in scleractinian corals. However, morphology often conflicts with genetic approaches due to high phenotypic plasticity and convergence. Understanding morphological variation among species is crucial to studying coral distribution, life history, ecology, and evolution. Here, we present an application of Random Forest models for coral species identification based on morphological annotation of the corallum and corallites. We show that the integration of molecular and morphological trait analysis can be improved using machine learning. Morphological traits were documented for Porites and Pocillopora coral species that were collected and genotyped through genome-wide, genetical hierarchical clustering, and coalescence analyses for the Tara Pacific Expedition. While Porites only included three tentative species, most Pocillopora species were accounted by included specimens from the western Indian Ocean, tropical Southwestern Pacific, and southeast Polynesia. Two Random Forest models per genus were trained on the morphological annotations using the genetic lineage labels. One model was developed for in-situ image identification and used corallum traits measured from in-situ photographs. Another model for integrative species identification combined corallum and corallite data measured on scanning electron micrographs. Random Forest models outperformed traditional dimension reduction methods like PCA and FAMD followed by k-means and hierarchical clustering by classifying the correct genetic lineage despite morphological clusters overlapping. This machine learning approach is reproducible, cost-effective, and accessible, reducing the need for taxonomic expertise. It can complement molecular and phylogenetic studies and support image identification, highlighting its potential to advance a coral integrative taxonomy workflow.
Phototriggered LYTAC: Photoactive Bispecific Aptamer Chimera Enhances Targeted Degradation of Membrane Protein through Regulating Cell Autophagy
Exploring the hydrophobic effects of quaternary ammonium copolymers on corrosion of casing and tubing steel in acidic solution
By encouraging improved adsorption onto metal surfaces and creating a more powerful barrier against corrosive chemicals, the hydrophobic property of corrosion inhibitors raises inhibition efficiency and decreases corrosion rates. This work aims to synthesize and describe three quaternary ammonium-based copolymers (AMCs) with different hydrophobic qualities and investigate their ability to inhibit P110 CS corrosion in 15% HCl, which is helpful for casing and tubing. The results showed that AMCs act as efficient corrosion inhibitors, with over 90% inhibition efficiency (%IE ) at 20 ppm concentration. The electrochemical investigation results indicated that the AMCs with hydrophilic and hydrophobic ratios of 100 (5), 90:10 (6a), and 80:20 (6b) manifest %IE of 87.74%, 92.12%, and 93.53%, respectively. The electrochemical investigations show that at the metallic surface’s active areas, AMCs successfully replace the pre-adsorbed water molecules. They are categorized as mixed-type corrosion inhibitors because they prevent both anodic and cathodic reactions without appreciably changing the corrosion potential (Ecorr). Their adsorption on the metallic surface follows the Langmuir adsorption isotherm. Surface analysis tools like SEM and EDX are utilized to investigate the corrosion prevention mechanism of adsorption. The DFT analysis results show that quaternary nitrogen atoms of hydrophilic and hydrophobic moieties play a key role in the adsorption and charge-sharing processes. Finally, the corrosion prevention mechanism of AMCs is explained using a graphic depiction based on the ideas of electrochemical, surface, and computational studies.
Iron-Catalyzed Enantioconvergent Amination of Alcohols
Obstetricians’ views on extending the 12-week abortion limit in Belgium: A qualitative study
Aim This study explores the views of obstetricians on a potential extension of the 12-week limit on elective abortion in Belgium. It aims to investigate perspectives from a distinct group of providers who already have experience with later abortion, albeit provided on medical grounds. These insights could help identify and navigate perceived challenges and opportunities of extending the abortion time limit. Methods We conducted semi-structured qualitative interviews with 23 hospital obstetricians who are involved in abortion on medical grounds in Flanders, Belgium. We coded and thematically analyzed interview transcripts with NVivo software. Results We discerned three major themes in obstetricians’ views: 1) Concerns about later abortion techniques; 2) Psychosocial hardships justifying later abortion; and 3) Fetal viability and feticide considerations. Minor themes are: 4) Limited impact on abortion for fetal anomaly; 5) Abortion travel and associated harms; and 6) Sex-selective abortion. Conclusion Flemish hospital obstetricians highlight both moral and technical challenges associated with extending the abortion time limit, primarily relating to surgical abortion methods and the organization of care. This study finds that, if an extended limit were to be adopted, additional policies and safeguards would facilitate implementation and foster interest among obstetricians in providing services. These include education and technical training of providers in later abortion care, centralization of provision, appropriate facilities, prepared teams, value workshops, and adequate state financing.