Search Results (262)

Background: The Eastern Cape Province carries the second-highest antenatal HIV prevalence nationally (32.9%), yet province-level longitudinal data on HIV incidence among pregnant and breastfeeding women (PBW) remain limited. This study examined trends in HIV incidence, HIV prevalence, mother-to-child transmission (MTCT), and antiretroviral therapy (ART) coverage among PBW in the Eastern Cape from 2000 to 2023. Methods: A quantitative ecological design was employed using secondary analysis of modelled estimates from the Thembisa Provincial HIV Model, version 4.8. Annual HIV incidence in PBW, HIV prevalence in pregnant women (overall and by five-year maternal age group), MTCT rate, new MTCT cases, and ART coverage were extracted with 95% confidence intervals (CIs) for the Eastern Cape, 2000–2023. Descriptive analysis characterised temporal trends at seven reference years, and formal trend significance was assessed using the Mann–Kendall test and log-linear regression. Results: HIV incidence in PBW declined from 3.8% (95% CI: 3.7–3.9) in 2000 to 1.8% (95% CI: 1.3–2.4) in 2023, a relative reduction of approximately 53%. ART coverage rose from 0% to 71.6%, coinciding with an 88% reduction in MTCT rate from 31.3% to 3.6%. By 2023, the MTCT rate had crossed below the World Health Organization 5% elimination threshold. HIV prevalence among pregnant women remained high at 25.0% despite declining incidence. The age distribution of HIV burden shifted markedly toward older maternal cohorts: prevalence among women aged 40–49 years increased from 9.9% in 2000 to 46.5% in 2023, while prevalence in the 15–24 age group declined substantially. New MTCT cases fell from 9990 in 2000 to 1236 in 2023. Conclusions: Declining HIV incidence in PBW coincided with substantial ART scale-up in the Eastern Cape, while HIV prevalence among pregnant women remained persistently high, a divergence that reflects the accumulating, ART-sustained pool of women living with HIV who survive into older reproductive age rather than a reversal of programmatic progress; this divergence between declining incidence and persistent, ageing prevalence is the central epidemiological finding of this study. Targeted interventions, including age-responsive antenatal protocols and strengthened PMTCT retention, alongside more careful consideration of expanded pre-exposure prophylaxis (PrEP) access, are needed to achieve elimination of mother-to-child transmission. Full article

Heat stress impairs male reproductive function, but whether acute heat stress alters glutamine-derived carbon labeling in Sertoli cells and whether melatonin modulates this response remain unclear. This study aimed to determine whether acute heat stress alters glutamine-derived carbon labeling in primary goat Sertoli cells and to evaluate whether melatonin attenuates these heat stress-associated metabolic changes. Primary goat Sertoli cells were assigned to control, heat-stress, or heat-stress plus melatonin groups. Cells were labeled for 24 h with [U-¹³C₅] glutamine. Cells in the heat-stress and heat-stress plus melatonin groups were subsequently exposed to 42 °C for 0.5 h, whereas control cells were maintained at 37 °C. In the heat-stress plus melatonin group, melatonin (0.5 μM) was applied throughout labeling and heat exposure. GC–MS was used to measure mass isotopologue distributions, which were subsequently corrected for natural isotope abundance, and to calculate total ¹³C-labeled fractions of selected TCA cycle intermediates; extracellular acidification rate (ECAR)-derived parameters were measured as indirect indices of glycolysis-associated acidification. Heat stress increased the total ¹³C-labeled fraction of cis-aconitate and, as an exploratory combined readout, the unweighted average total ¹³C-labeled fraction of citrate and cis-aconitate; succinate and malate were unchanged, while fumarate decreased. Melatonin reduced the heat stress-associated total ¹³C-labeled fractions of citrate and cis-aconitate and decreased the relative abundance of cis-aconitate M + 5. Melatonin also attenuated heat stress-associated increases in ECAR-derived glycolysis, glycolytic capacity, and glycolytic reserve. These findings indicate that acute heat stress is associated with altered citrate/cis-aconitate ¹³C-labeling patterns that are potentially compatible with reductive carboxylation-related labeling but do not directly demonstrate altered pathway flux; these changes were attenuated by melatonin. Overall, the study objective was achieved by showing that acute heat stress altered citrate/cis-aconitate ¹³C-labeling patterns and increased ECAR-derived extracellular acidification in primary goat Sertoli cells, and that melatonin attenuated both responses. Further studies incorporating a melatonin-only group, dynamic isotope tracing, mitochondrial respiration measurements, redox analysis, and flux modeling are warranted to define the underlying metabolic routes more directly. Full article

Background/Objectives: Fertility preservation is a key component of cancer care in women of reproductive age, and controlled ovarian stimulation (COS) followed by oocyte/embryo cryopreservation is considered the standard strategy. Although COS protocols are generally standardized, systemic effects related to different malignancies may interfere with ovarian reserve assessment and influence stimulation planning and counselling. This study aimed to evaluate COS outcomes across different malignancy types in women undergoing fertility preservation. Methods: This retrospective study included 331 oncological patients who underwent COS for fertility preservation at a single referral center between May 2008 and May 2025. Patients were stratified into three groups according to malignancy type: breast cancer, hematological malignancies, and other cancers. Ovarian reserve was assessed using serum anti-Müllerian hormone (AMH) levels and antral follicle count (AFC). COS outcomes, including stimulation duration, total gonadotropin dose, number of retrieved and mature oocytes, follicular output rate (FORT), and follicle-to-oocyte index (FOI), were compared among groups. Results: Patients with hematological malignancies were significantly younger and showed higher AFC values compared with the other groups, whereas AMH levels did not differ significantly. After adjustment for age and AFC, patients with hematological malignancies showed significantly lower AMH levels compared with breast cancer patients (β = −0.94 ng/mL, 95% CI −1.40 to −0.48, p < 0.001), supporting the presence of a relative AMH–AFC discordance. In unadjusted analyses, gonadotropin requirements were higher in breast cancer patients, whereas the number of retrieved and mature oocytes was higher in patients with hematological malignancies. However, after adjustment for age and AFC, malignancy type was not independently associated with retrieved oocytes, mature oocytes, total gonadotropin dose, or stimulation duration. FORT and FOI were comparable among groups. Conclusions: Malignancy type did not appear to independently impair ovarian responsiveness to stimulation. Patients with hematological malignancies showed preserved stimulation outcomes despite AMH values not being proportionally higher than expected based on their younger age and higher AFC. These findings suggest that AMH should be interpreted with caution in systemic malignancies and that AFC may be particularly useful for tailoring fertility preservation counselling and stimulation strategies when AMH and AFC are discordant. Full article

Advanced methodologies for Botryllus schlosseri artificial seawater systems are needed to decrease dependency of large-scale culture on natural seawater and expand this important new model organism to more inland laboratories. We constructed two botryllid tunicate customized closed aquaculture systems, a static system consisting of aerated jars fed commercial filter feeder diet, and a recirculating aquaculture system (RAS) consisting of pertinent marine RAS components fed live microalgae and zooplankton diets. Initially, static tunicate culture yielded exponential growth in contrast to poor survival and negligible growth observed in RAS tunicates. RAS modifications were made to increase water treatment proficiency, which improved tunicate survival and growth. Experiments were performed isolating feed and water type as variables differentiating static and RAS and evaluating their specific effects. Live feed promoted five-fold greater growth relative to a commercial concentrate diet. Tunicates maintained in optimized RAS water achieved two-fold faster growth relative to animals in freshly prepared artificial seawater. Subsequent procedural modifications combined with the RAS revisions resulted in growth rates comparable to the static system. Both optimized systems are suitable for long-term husbandry of botryllid tunicate populations supporting both sexual and asexual modes of reproduction, with a current RAS residence time of over 24 months. Full article

Reliance on mineral fertilization in papaya cultivation raises sustainability concerns and drives demand for validated organic alternatives. This study tested whether integrating humic substances (HS) and sugarcane filter cake (FC) would stimulate photosynthetic physiology, upregulate carbon metabolism gene expression, and increase fruit yield in ‘Golden’ papaya while outperforming conventional NPK fertilization. A 12-month field experiment was conducted in a randomized complete block design with a factorial arrangement of four HS doses (0, 90, 180, and 270 mL plant⁻¹) combined with two FC doses (0 and 60 kg plant⁻¹) plus an NPK control, measuring photosynthetic pigments, gas exchange, relative expression of rbcL, ACC oxidase, invertase, relative growth rate, and fruit yield. Combined HS and FC increased chlorophyll a by up to 205%, chlorophyll b by 277%, and carotenoids by 208% relative to unamended controls. Gene expression was strongly induced: rbcL reached 202-fold, invertase 156-fold, and ACC oxidase 84.8-fold above control values. Photosynthetic rate followed a quadratic dose-response peaking near 90 mL plant⁻¹ HS. Fruit yield nearly doubled under the optimal combined treatment (115 t ha⁻¹) compared with unamended controls (62 t ha⁻¹) and NPK fertilization (66 t ha⁻¹). These results confirm that HS and FC act synergistically as dual-purpose amendments, improving soil fertility while biostimulating papaya physiology through coordinated upregulation of photosynthetic capacity and carbon partitioning toward reproductive sinks. Full article

Small pelagic fishes are essential for artisanal fisheries and food security in São Tomé and Príncipe, yet biological information required for stock assessment remains scarce. This study examined the population dynamics and life-history traits of Caranx crysos, Euthynnus alletteratus, Hemiramphus balao, and Cheilopogon melanurus using 9052 specimens collected from artisanal landings between 2023 and 2025. C. melanurus (35.2%) and H. balao (34.0%) dominated the sampled catches, followed by C. crysos (18.1%) and E. alletteratus (12.7%). Standardized CPUE series modelled using GAMs revealed significant temporal and seasonal variation in relative abundance, with contrasting species-specific trends. Length–weight relationships revealed negative allometric growth in three of the four species examined (75%), with b values ranging from 2.50 to 3.19, while Fulton’s condition factor differed significantly among species (Kruskal–Wallis χ² = 6702.7, p < 0.001). Sex-ratio analyses showed significant deviations from parity in C. crysos and C. melanurus, whereas E. alletteratus and H. balao remained balanced. Gonadosomatic index and maturity-stage distributions indicated year-round reproductive activity with distinct spawning peaks. Length at first maturity (L50) ranged from 30.2 cm to 38.8 cm among species. Growth parameters estimated from length-frequency data using the von Bertalanffy Growth Function fitted through ELEFAN_GA in TropFishR yielded L∞ values of 43.9–68.4 cm and K values of 0.065–0.336 yr⁻¹. Growth performance index (φ′) ranged from 2.48 to 2.99, corresponding to theoretical longevities of 8.9–46.3 years. Length-based cohort analysis indicated biomass concentration in intermediate size classes and increasing fishing mortality towards larger individuals. Exploitation rates revealed contrasting fishing pressures among species, while sensitivity analyses identified growth and mortality parameters as the main sources of uncertainty. These findings provide the first integrated biological baseline for the assessment and management of small pelagic resources in São Tomé and Príncipe. Full article

The Tomarrazón-Camarones Basin (La Guajira, Colombia) is characterized by frequent, widespread flooding and, anthropogenically, by intense instream sediment mining. Mapping flood hazard is hence essential to develop effective flood management plans, and a knowledge of the water regime (duration curves) is also essential to estimate sediment transport and carry out sediment budgets to inform on the impacts and sustainability of the mining activity. However, neither water levels nor discharges are monitored by official gauging stations, and only a few rainfall gauging stations are available in the area, with daily records often affected by data gaps. Therefore, a first challenge is to reconstruct discharge time series by an affordable effort, scaled to the financial-labour resources available in that challenging context. This paper presents an integrated approach that combines satellite-derived rainfall data with ground observations. A semi-distributed hydrological model (HEC-HMS, SCS-CN method) is used to reconstruct the full flow-rate time series once calibrated and validated with data derived from automatic sensors and field measurements. The model is fed with hourly data derived from daily data at ground gauging stations temporally downscaled by adopting the spatially distributed hourly rainfall patterns obtained from satellite records. Before that, observed water levels in three stations equipped with water level sensors were translated into discharge time series using analytical relationships based on field-measured geometric and physical characteristics. Then, these event-based hydrographs were used to calibrate and validate the model. Results show good agreement with observations, with R² = 0.981 and a relative RMSE of 40% for overall hydrograph reproduction, and R² = 0.87 for peak flow estimation, supporting a reasonable confidence in the approach. The calibrated model is then applied to long-term datasets (1973–2024) to retrieve duration curves and return periods of peak discharges. Full article

Cultivars of strawberry (Fragaria × ananassa) differ in photoperiodic responses, which influence the balance between vegetative and reproductive growth, shaping canopy development, biomass production, and water use efficiency (WUE). Using 3D point-cloud phenotyping, this study compared the canopy structure and WUE of the short-day cultivar ‘Sonata’ and long-day cultivar ‘Favori’ grown under identical greenhouse conditions. Cultivar-specific growth and water use traits were quantified using daily non-destructive 3D point cloud phenotyping combined with continuous whole-plant gravimetry, supported by manual and destructive measurements. Non-destructive estimates of plant height and digital biomass corresponded moderately to measurements (height: R² = 0.628; biomass: R² = 0.579; mean absolute percentage error (MAPE) = 13.86%). Growth analysis indicated similar relative growth rates between the two cultivars, whereas the crop growth rate was higher in ‘Sonata’ than in ‘Favori’. Integration of growth estimates with gravimetric records revealed higher period average WUE in ‘Sonata’ (3.1 mg g⁻¹) than in ‘Favori’ (2.5 mg g⁻¹). These results highlight the distinctive growth strategies of a canopy-driven pattern in ‘Sonata’ and a reproduction-driven pattern in ‘Favori’. The combined 3D phenotyping–gravimetry framework provides a high-resolution, non-destructive approach to quantify cultivar-specific growth and water use traits. Full article

Neospora caninum is a major cause of reproductive failure in cattle, responsible for epidemic abortion outbreaks that inflict annual billion-dollar losses on the global livestock industry. In water buffaloes (Bubalus bubalis), however, a phylogenetically close relative often raised in the same environments, the same parasite typically establishes a subclinical persistent infection with markedly lower rates of clinical abortion. This review inverts the traditional narrative by arguing that the key to next-generation control strategies lies in understanding the tolerant host (buffalo) rather than solely the susceptible host (cattle). By dissecting this “Neospora paradox”, we explore the molecular and immunological crosstalk that dictates pregnancy outcomes. We examine the parasite’s invasion proteins, revealed by CRISPR-Cas9 screens, and the maternal–fetal interface, where the balance between immune tolerance and parasite control determines the fate of pregnancy. We also compare N. caninum with the related zoonotic parasite Toxoplasma gondii to highlight how differential host immune recognition shapes infection outcomes. Finally, we propose that deciphering the buffalo’s successful equilibrium with N. caninum can illuminate novel pathways for vaccines and immunotherapeutic strategies, transforming the management of neosporosis worldwide. Full article

To determine the optimal water temperature range for artificial breeding and early development of Osteochilus salsburyi, six water temperature gradients (14, 18, 22, 26, 30, and 34 °C) were set to systematically investigate the effects of water temperature on artificial reproduction efficiency, embryonic development, the morphology of newly hatched larvae, larval growth performance, and the timing of organ development in O. salsburyi. The results showed that the spawning induction rate of O. salsburyi reached 100% at 14–30 °C. The fertilization rate and hatching rate peaked at 18–22 °C, and no fertilization was completed at 34 °C. The malformation rates of embryos and larvae showed a U-shaped change, with the lowest malformation rate at 18 °C, and the teratogenic effect of high-temperature stress was more significant. The embryonic development rate was significantly negatively correlated with water temperature, and the development duration was significantly shortened with increasing water temperature. Embryonic development was arrested and all embryos died at 34 °C, while hatching could be completed at 14 °C but with an excessively long cycle. The morphological indicators of newly hatched larvae showed differentiated sensitivity to water temperature; total length, pre-anal length, and body height were highly sensitive indicators, and larvae exhibited balanced and robust morphological development at 18–22 °C. The larval survival rate first increased and then decreased with increasing water temperature, reaching the highest rate at 22–26 °C. The absolute growth increment, relative growth increment, and specific growth rate (SGR) continued to increase with increasing water temperature. The timing of larval organ differentiation and behavioral development was significantly advanced with increasing water temperature. Late organ development of larvae was blocked at 14 °C, only early development was completed at 34°C, and the internal and external organs of larvae developed completely and in an orderly manner at 18–30 °C. In summary, the optimal water temperature for artificial breeding and early development of O. salsburyi is 18–26 °C, among which 18–22 °C is the best for artificial reproduction and 22–26 °C is optimal for larval rearing. The results can provide a scientific basis for the precise regulation of water temperature in large-scale seedling production of O. salsburyi. Full article

In recent decades, conservation of local poultry breeds has gained relevance to preserve genetic resources adapted to low-input systems and to enhance their valorization. This study addresses a key knowledge gap by providing a comprehensive characterization of the endangered Murciana chicken breed, native to southeastern Spain. We jointly evaluate recent population dynamics, conservation framework, morphology and morphometrics, growth patterns, and reproductive and productive traits. Data includes census and pedigree records, standardized morphological assessments, growth modeling, and production data from the conservation nucleus. The population increased from fewer than 150 registered animals in 2017 to more than 550 in 2024, indicating stabilization. The breed showed characteristics of slow-growing dual-purpose Mediterranean genotypes, with marked sexual dimorphism, Gompertz relative growth rates of 0.020 d⁻¹ (males) and 0.023 d⁻¹ (females), and adult weights of 3.2 kg and 2.4 kg, respectively. Carcass yield was moderate (61.9%), with higher leg (36.7%) than breast proportion (16.9%). Reproductive (fertility 88.6%, hatchability 80.6%) and laying performance (116.6 eggs/hen/year) were consistent with local extensive systems. These results provide a robust baseline to support conservation, genetic management, and sustainable use of the Murciana chicken breed, contributing to its long-term preservation and valorization. Full article

Whether learned cognition can affect evolutionary outcomes remains a long-standing question. This study addresses a narrower mechanism: whether a model-based planner benefits from learned rules that explicitly condition on the action just taken. The testbed is a spatial artificial ecology with plants, shelters, a predator, reproduction, and a day/night cycle. Five rule-use arms are evaluated on matched simulation seeds. At age 200, agents switch to a weaker learned-lite planner that relies more strongly on learned rule predictions. The pre-specified hypothesis is that access to filtered action-conditioned rules improves outcomes relative to an otherwise identical no-rule-policy baseline, in which rules are still induced and stored but are not used for action selection. In thirty paired replicates under the default reproductive gates, the action-conditioned arm outperforms the no-rule baseline on all four pre-specified primary endpoints. The strongest effect is behavioural: the action arm produces 91.4 additional successful post-switch eating events per run ($d_z=1.56$, 93.3% paired win rate, $p<{10}^{-4}$). It also produces 10 additional crystallized clean-causal rules per replicate ($d_z=0.58$, $p_t=0.0034$). All four primary paired-t p-values remain significant after Bonferroni correction across the four-endpoint family. A diagnostic check shows that omitting reproductive cooldown from the planner’s rollout reverses the arm ordering on the same paired seeds; reinstating cooldown recovers the reported result. Two exploratory checks delimit the claim: broad unfiltered rule access can impair foraging, and a means–ends extension shifts behaviour toward reproduction without producing a robust whole-life fitness gain. Within this simulation, access to action-conditioned rules has a measurable effect on post-switch behaviour that is distinct from passive environmental prediction and from clean-crystallized rules alone. Full article

The invasive plant Datura stramonium L. possesses strong reproductive capacity and ecological adaptability, showing a tendency to spread rapidly, especially in highly human-disturbed habitats. To explore its resource utilization pathway—turning waste into wealth—and to address toxic metal pollution in strongly human-disturbed areas (such as mining regions), this study evaluates its phytoremediation potential in contaminated soils on the Qinghai–Tibet Plateau. We established a non-planted control and three planting density treatments to compare the removal rates of Pb, Cd, Cr, and As. To our knowledge, this is the first study to assess how planting density influences the multi-metal phytoremediation performance of this invasive species in a high-altitude plateau environment. The results showed that planting significantly increased toxic metal removal rates, with overall efficiency generally improving at higher densities, particularly for Cr. Analysis of bioconcentration and translocation factors revealed distinct element-specific accumulation patterns. Pb and As were primarily enriched and retained in the roots. Interestingly, while Cd exhibited a strong localized tendency to accumulate in the leaves, its overall root-to-shoot translocation remained relatively restricted at the whole-plant level, similar to Cr. Overall, D. stramonium functions primarily through root stabilization for Pb, As, and Cr, alongside partial aboveground accumulation for Cd. However, given its toxic and invasive nature, any practical phytoremediation application requires strict post-harvest biomass management and ecological monitoring to prevent secondary spread. Full article

To examine how host plant identity shapes the performance of the invasive pest Spodoptera frugiperda (J.E. Smith), three sweet potato varieties (Qianshu 12, Qianshu 17, and Yushu 13) were evaluated under laboratory conditions, with maize (Xida 818) as a control. Development, survival, reproduction, and population parameters were assessed using an age-stage, two-sex life table approach. The results demonstrated that S. frugiperda completed its life cycle on all sweet potato varieties. The developmental period was significantly different in the larval stage. S. frugiperda fed with Yushu 13 had the longest pupal duration (9.97 d) and preadult duration (37.94 d). Reproductive performance was also reduced on sweet potato: adults reared on maize showed greater longevity and higher fecundity, whereas no significant differences were found between Qianshu 17 and Yushu 13. Survival patterns differed among host plants and developmental stages. Early instar survival was highest on Qianshu 12 but lowest on Yushu 13, and Qianshu 12 supported relatively higher survival from late larval stages to adulthood. Life table analysis further showed that larvae fed with three sweet potato varieties exhibited a lower net reproductive rate (R₀), intrinsic rate of increase (r), finite rate of increase (λ), and longer mean generation time (T) compared to those fed with corn. Overall, although sweet potato can support the development of S. frugiperda, it constrains reproduction and population growth, indicating lower host suitability. Full article

The house fly, Musca domestica L., is a medically important cosmopolitan pest distributed worldwide. Diflubenzuron, a chitin synthesis-inhibiting insect growth regulator, is widely used for the control of medically important insect pests. In this study, the biological and population characteristics of diflubenzuron-unselected (Diflu-Unsel) and diflubenzuron-selected (Diflu-Sel) M. domestica were evaluated using the age–stage, two-sex life-table theory to support resistance management efforts. The results showed that the Diflu-Sel (G₄₆) strain developed 319.935-fold resistance to diflubenzuron after 42 generations of selection compared with the Diflu-Unsel (G₄₆) strain. Using the LC₅₀ of diflubenzuron in the Diflu-Unsel (G₅) as the parental generation before selection, the realized heritability (h²) of diflubenzuron resistance was estimated as 0.054. Larval and pupal development durations and the total preoviposition period were significantly prolonged, whereas adult duration, total longevity from egg to adult, oviposition period, and fecundity were significantly reduced in the Diflu-Sel (G₄₆) strain compared with the Diflu-Unsel (G₄₆) strain, resulting in a relative fitness value of 0.39. Population parameters, including the intrinsic rate of increase, finite rate of increase, generation time, doubling time, gross reproductive rate, and net reproductive rate, were significantly lower in the Diflu-Sel (G₄₆) strain than in the Diflu-Unsel (G₄₆) strain. These results demonstrate that resistance to diflubenzuron can evolve in M. domestica but may be accompanied by substantial fitness costs, which may facilitate resistance management. The findings provide valuable insights for designing sustainable diflubenzuron resistance management strategies for M. domestica. Full article