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Germination and establishment of Teramnus labialis (l.f.) sprenG plants are affected by scarification treatment used
(Sociedad Botanica de Mexico, A.C, 2025) Naidoo, Sershen; Acosta, Yanier; Sánchez, Jorge A.
Background: Some of the species that make up the legume family are used as animal feed and to improve soil fertility. However, their use is limited due to low seed availability and low germination rates. Questions: Which scarification treatment is most effective in increasing germination? What is the response of plants to growth under field conditions? Studied specie: Teramnus labialis (L.f.) Spreng. Study site and date: Ciego de Ávila, Cuba, 2019 year. Methods: Four scarification treatments (sanding, sulfuric acid, hot water, and liquid nitrogen (LN)) were evaluated under controlled laboratory and field conditions. Seed coat structures, imbibition capacity, electrolyte loss, and germination were studied under controlled laboratory conditions. Under field conditions, plant morphological traits were evaluated during the vegetative and reproductive phases. Results: Scarification with LN caused multiple cracks in the seed coat, while sulfuric acid caused wear and detachment of the seed coat. With the use of LN, seed imbibition and germination were improved. In addition, 78 % of plants emerged with this treatment and crop establishment was achieved 120 days after sowing. Conclusions: Scarification with LN of T. labialis seeds was the most effective treatment to improve germination and reduce the time to establishment of the species. © 2025 Sociedad Botanica de Mexico, A.C.
Student assessments of early childhood caries in some Informal settlements of Cape Town: a 10-year series of cross-sectional studies
(John Wiley and Sons Ltd, 2025) Myburgh, Neil; Krekmanova, Larisa; Lundgren, Ted
Aim: To assess Early Childhood Caries by measuring the dmft, Significant Caries Index (SiC), pufa, and caries-free status in informal settlements outside Cape Town, South Africa over a 10-year period. Method: A series of cross-sectional studies over a 10-year period (2009–2019). Surveys were carried out in preschools in informal settlements. A total of 5090 children aged from 1 to 5 years of age were examined. Results: For 1- to 3-year-olds, the mean dmft was 4.33 ± 1.55, and for 4- and 5-year-olds, it was 6.34 ± 1.48. The difference in dmft for 1- to 3-year-olds increased but did not differ statistically between 2009 and 2019. For 4–5 years old, there was an increase over time. For 1- to 3-year-olds, the mean pufa was 0.34 ± 0.28, and for 4- to 5-year-olds, it was 0.63 ± 0.59. For 1- to 3- and for 4- to 5-year-olds, there was a statistically significant, lower pufa 2009–2019. For 1- to 3-year-olds, the mean SiC was 11.0 ± 2.35, and for 4- to 5-year-olds, it was 12.05 ± 1.89. There was a difference in SiC for 1–3 and for 4- to 5-year-olds, which was higher but did not differ statistically 2009–2019. Among 1- to 3-year-olds, 32.1% were assessed as caries-free. Among 4- to 5-year-olds, 16.0% were caries-free. There was a statistically significant, lower number of caries-free 1- to 3-year-old and 4- 5-year-old children 2009–2019. Conclusions: The mean dmft has been found to be continuously high from 2009 to 2019. The SiC score remained unchanged, whereas pufa was significantly lower. The frequency of caries-free children was lower over time.
Aptamer-driven biosensor technology for the quantitative analysis of C-reactive protein
(John Wiley and Sons Inc, 2025) Oranzie, Marlon; January, Jaymi L; Sanga, Nelia A.; Leve, Zandile D; Mini, Sixolile; Cupido, Candice; Douman, Samantha F; Iwuoha, Emmanuel I.
C-reactive protein (CRP) is a widely recognized biomarker for early myocardial infarction (MI) detection, released into the bloodstream during heart inflammation. Traditional assays for CRP detection, like ELISA and immunoradiometric assays, are costly, time-consuming, and require large sample volumes. Aptasensors are becoming increasingly popular for MI diagnosis due to their affordability, simplicity, and potential for point-of-care use. In this study, an electrochemical aptasensor incorporating mercaptosuccinic acid-capped nickel selenide quantum dots (MSA-NiSe2 QD) were developed for CRP detection. The amine-modified aptamer was immobilized on the MSA-NiSe2 QD using EDC/NHS coupling chemistry. Chronocoulometric measurements showed high selectivity towards CRP in phosphate buffer, with a linear range of 10–110 pg/mL and a detection limit of 2.80 pg/mL. Cross-reactivity experiments confirmed the aptasensor's high selectivity for CRP. Testing in human serum samples demonstrated recovery rates of 94–100.5 %, indicating its suitability for clinical diagnostics. Validation studies with a commercial CRP ELISA kit showed the aptasensor's superior sensitivity in both physiological buffer and human serum.
Isoprene emissions, oxidation chemistry and environmental impacts
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Shallcross, Dudley; Khan, Md Anwar Hossain; Holland, Rayne
Isoprene emissions can affect the oxidizing capacity of the atmosphere and are likely to increase with an increase in the world’s biomass. The emission of isoprene is strongest in tropical forested regions, suggesting a major portion of tropospheric chemistry occurs in the tropics. As well as deforestation and reforestation having a direct impact on the world’s climate through land cover, there is also an indirect environmental impact (e.g., global warming, air pollution) through the resulting change in isoprene emissions. Previously, incomplete understanding of isoprene oxidation chemistry caused a model-measurement breakdown for concentrations of HOx radicals observed over certain low-NOx regions, such as the pristine Amazon rainforest. Over the last decade, however, understanding of isoprene oxidation chemistry has been vastly improved. Numerous research studies have provided evidence for the involvement of 1,6-H and 1,5-H shift reactions in the isoprene oxidation mechanism, which increases the level of HOx recycling that occurs. As well as helping to reduce the model-measurement breakdown observed, the updated isoprene oxidation mechanism affects the tropospheric burdens of other species, including carbon monoxide (CO), methane (CH4), ozone (O3), organic peroxides (ROOH), secondary organic aerosol (SOA), and organic nitrates (RONO2). There are still gaps in the understanding of the impacts and oxidation chemistry of isoprene emissions, which this literature review identifies and discusses. In the future, there is still much scope for further research, including modeling future reforestation scenarios with isoprene emissions and their impacts on both global and regional scales.
Screening for retinopathy of prematurity (ROP) in South Africa: data from a newly established prospective regional register
(BMJ Publishing Group, 2025) Jordaan, Esmè; van der Lecq, Tshilidzi; Rhoda, Natasha
Objective Retinopathy of prematurity (ROP) registers enable population-based studies to monitor ROP screening programmes to improve their effectiveness. The aim of this study was to determine the frequency of ROP and the coverage of screening in a South African cohort using a prospective ROP South African (ROPSA) register. Methods and analysis Infants born from 1 May 2022 to 31 January 2023 and screened prospectively for ROP at five neonatal intensive care units in Cape Town were included. The screening criteria were a gestational age (GA) <32 weeks or birth weight (BW) <1250 g. Data were extracted from the ROPSA register and analysed. Results 696 of 1154 (60.3%) eligible infants were screened, almost half of whom (45.7%) did not complete screening. ROP was detected in 220 infants (31.6%, 95% CI 28.3% to 35.3%), 7 (1.0%) of whom required treatment. Infants with incomplete screening had a lower mean GA than those who completed screening; 28.7 (SD 1.6, range 25-33) and 29.1 (SD 1.7, range 24-36) weeks, respectively (p=0.004) and a lower mean BW; 1048 (SD 203, range 650-1690) g and 1108.5 (SD 227, range 640-1840) g, respectively (p<0.001). Conclusions Data from the ROPSA register on the frequency of any ROP and treatment-requiring ROP may be biased due to low screening coverage and high incomplete screening. Reasons need to be explored and corrective interventions initiated. The ROPSA register will enable the impact of these interventions to be monitored. The findings of this study will contribute to the ongoing revision of South African national ROP screening guidelines.