Search Results (424)

During blast shock wave pressure measurement, strong mechanical vibrations and shocks can affect the dynamic characteristics of shock wave pressure sensors, introducing measurement errors. To improve measurement accuracy for the compression phase, a specialized buffer device was designed to enhance the sensor’s dynamic response to transient pressure rises. Using a double-diaphragm shock tube, the dynamic calibration of the enhanced sensor system was carried out and the influence of the buffer device on the dynamic performance was investigated. A mathematical model based on a backpropagation (BP) neural network was developed to characterize the sensor system, and a dynamic compensation method was implemented to improve the enhanced shock wave pressure sensor system. Experimental results demonstrated that while the buffer device significantly reduced the operational bandwidth of the sensor system, the BP neural network-based dynamic compensation effectively widened the bandwidth and improved measurement accuracy. This research provides a practical solution for high-precision dynamic pressure measurement, specifically targeting the compression phase in complex environments. Full article

In this study, SweAMI FISH fluorescence in situ hybridization and immunofluorescence were used to analyze the spatiotemporal expression characteristics of the TBXT gene and Brachyury protein in 16-day-old Hulunbuir sheep embryos and 19-day-old Hu sheep embryos and to explore their regulatory effects on the development of sheep tails and related organs. The study showed the following: At 16 days of embryonic age, the TBXT gene was concentratedly expressed in the heart, somites, neural tube, and mesonephros of both sheep breeds; at 19 days of embryonic age, it was concentratedly expressed in the limb ectoderm and tail bud of Hulunbuir sheep, and in the midgut and tail bud of Hu sheep. At 16 days of embryonic age, the BRACHYURY protein was concentratedly expressed in the neural tube, somites, brain vesicles, and mesonephros of both sheep breeds; at 19 days of embryonic age, it was concentratedly expressed in the heart and hindgut of Hulunbuir sheep, and in the tail bud and hindgut of Hu sheep. In summary, this shows that there are differences in the temporal and spatial expressions of the TBXT gene and BRACHYURY protein between the two sheep breeds. There are also site-specific and time-specific differences in the regulation of the above genes and proteins during tail and related organ development between the two breeds, which confirms that the molecular regulation pathways of tail and related organ development are different between the two breeds. This study provides an experimental basis for screening molecular markers related to goat tail development and breed improvement. Full article

Background: While the importance of folic acid supplementation during pregnancy in the prevention of neural tube defects in offspring is well established, its potential role in pediatric asthma development remains unclear, with limited evidence to date. Objective: To identify perinatal and environmental factors that modify the association between maternal folic acid intake and pre-adolescent asthma. Methods: Cross-sectional analysis of the Healthy Growth Study that consisted of 2332 pre-adolescents (mean age 11 years; asthma n = 451); 50% boys attending elementary schools in Greece. Questionnaires were used to collect data on sociodemographic, perinatal, and environmental characteristics as well as asthma prevalence and maternal folic acid supplementation during pregnancy (trimesters 1, 2, and 3). Logistic regression models explored the association between maternal folic acid supplementation and pre-adolescent asthma, accounting for perinatal and environmental exposures. Results: Adjusted regression models showed that maternal folic acid supplementation during the third trimester was associated with 34% increased odds of pre-adolescent asthma. Stratified analyses per perinatal and environmental factors revealed significantly higher asthma odds with folic acid supplementation during the second and third trimesters among pre-adolescents born < 37 weeks; non-smoking mothers; in pre-adolescents attending schools of low socioeconomic level; and in neighborhoods having less traffic and more parks. Contrastingly, in appropriate for gestational age (AGA), an infant’s first-trimester supplementation increased asthma odds. Conclusions: Maternal folic acid supplementation, particularly in later trimesters, was modestly associated with increased odds of pre-adolescent asthma, modified by perinatal and environmental factors. Future research should explore whether continued folic acid supplementation beyond the first trimester carries differential risks or benefits in asthma. Full article

Lead is a naturally occurring metal found in numerous compounds used in everyday life. Toxicity from lead is a well-known public health problem. Its effects are implicated in multiple tissues, encompassing the gastrointestinal, renal, cardiovascular, and neurological systems. Endocannabinoid receptors are involved in each of these systems, but the effects of lead on the receptors themselves are not well elucidated. In the neurological system, lead has varying interactions with neurotransmitters and downstream regulators implicated in neuronal transmissions influenced by endocannabinoid receptor function. Lead’s effect is likely indirect on endocannabinoid receptor function; however, its influence on neuronal function is likely inhibitory to the receptor’s functioning. Lead has also been implicated in oxidative stress states, which would influence endocannabinoid receptors’ function. The literature clearly supports lead having a negative impact on the overall function of endocannabinoid receptors, setting the stage for pathological states related to diminished neurosynaptic function and, in embryology, altered neuronal development, especially of the neural tube. Full article

Background and Clinical Significance: Neural tube defects (NTDs) represent a group of malformations, typically arising from a complex interplay between genetic susceptibility and environmental influences. Increasing evidence points to the contribution of rare pathogenic variants in genes involved in embryonic development in selected cases. To date, two families with NTDs carrying biallelic variants in TRIM36 and NUAK2 have been described. Specifically, germline homozygous pathogenic variants in NUAK2 were identified in three fetuses with anencephaly, thus implicating this gene as a critical regulator of neural tube closure. Case Presentation: We describe a family in which five individuals presented with sacral dimples, a subtle midline defect considered a minor malformation. Exome sequencing revealed a heterozygous missense variant, c.487G>A in NUAK2, segregating with the phenotype. Although sacral dimples are often clinically silent and do not typically cause functional impairment, their presence in multiple relatives highlights a possible shared genetic etiology. Careful phenotypic recognition of such findings can therefore provide valuable insights into underlying molecular mechanisms. Conclusions: This report extends the clinical spectrum of NUAK2-related anomalies by demonstrating a novel genotype–phenotype correlation. Our findings suggest that variants in this gene may follow a semi-dominant inheritance pattern, with heterozygous carriers manifesting milder phenotypes, such as sacral dimples, while biallelic pathogenic variants lead to severe NTDs. This observation reinforces the association between NUAK2 loss-of-function variants and NTDs and emphasizes the importance of genetic investigations in families where such dysmorphic traits recur. Ultimately, these results contribute to clarifying the molecular basis of NTDs and may inform both genetic counseling and risk stratification in affected families. Full article

Introduction: Anemia, characterized by a reduction in hemoglobin concentration, is a widespread health concern globally, impacting individuals across various demographics. Iron deficiency, often compounded by inadequate folic acid levels, is a primary driver. This review aims to consolidate current evidence and offer a practical recommendation regarding the role of folic acid 1 mg + iron (ferrous sulfate) 90 mg supplementation in both preventing and treating anemia. Objective: We aimed to provide a comprehensive review and recommendation regarding the use of folic acid 1 mg + iron (ferrous sulfate) 90 mg supplementation in the prevention and treatment of anemia in adults, based on current evidence and clinical experience. Methods: A thorough literature review was conducted, encompassing studies, guidelines, and meta-analyses related to iron deficiency, anemia, and folic acid supplementation. This review incorporated data from sources such as the World Health Organization (WHO), the European Hematology Association (EHA), and Cochrane Database. Clinical experience of the authors was also taken into account. Results: Anemia, a prevalent hematological condition, affects a significant portion of the global population. The risk factors for iron deficiency and iron deficiency anemia include age, menstruation, pregnancy, dietary restrictions, chronic diseases, and inflammatory conditions. Accurate diagnosis of anemia involves reticulocyte count, morphological classification, and identification of the underlying etiology. Oral iron salts, particularly ferrous sulfate, are the first-line treatment for uncomplicated iron deficiency anemia, with lower doses or alternate-day dosing improving tolerability. Adequate folic acid availability is crucial for erythropoiesis, and supplementation is safe and enhances treatment response, especially in mixed deficiency anemia. A fixed-dose combination of folic acid 1 mg + iron (ferrous sulfate) 90 mg is effective and well-tolerated for the treatment of iron deficiency anemia, mixed nutritional anemia, and iron deficiency without anemia in adults. Conclusions: Based on extensive scientific evidence and clinical experience, the combination of folic acid 1 mg + iron (ferrous sulfate) 90 mg is a valuable therapeutic option for the prevention and treatment of anemia. This combination should be indicated for iron and folic acid deficiency during pregnancy, lactation, and the postpartum period and for the prophylaxis and treatment of anemia during pregnancy and in adults in general. This approach enables correction of folate deficiencies, optimizing treatment response and ensuring sufficient folic acid levels, particularly in cases of incomplete adherence or missed doses, and is critical during pregnancy to minimize the risk of neural tube defects. Full article

Proper estimation of flowing bottomhole pressure at coiled tubing depth (BHP-CTD) is crucial in optimization of nitrogen lifting operations in oil wells. Conventional estimation techniques such as empirical correlations and mechanistic models may be characterized by poor generalizability, low accuracy, and inapplicability in real time. This study overcomes these shortcomings by developing and comparing sixteen machine learning (ML) regression models, such as neural networks and genetic programming-based symbolic regression, in order to predict BHP-CTD with field data collected on 518 oil wells. Operational parameters that were used to train the models included fluid flow rate, gas–oil ratio, coiled tubing depth, and nitrogen rate. The best performance was obtained with the neural network with the L-BFGS optimizer (R² = 0.987) and the low error metrics (RMSE = 0.014, MAE = 0.011). An interpretable equation with R² = 0.94 was also obtained through a symbolic regression model. The robustness of the model was confirmed by both k-fold and random sampling validation, and generalizability was also confirmed using blind validation on data collected on 29 wells not included in the training set. The ML models proved to be more accurate, adaptable, and real-time applicable as compared to empirical correlations such as Hagedorn and Brown, Beggs and Brill, and Orkiszewski. This study does not only provide a cost-efficient alternative to downhole pressure gauges but also adds an interpretable, data-driven framework to increase the efficiency of nitrogen lifting in various operational conditions. Full article

The evaluation of pressure drops across the length of production wells is a crucial task, as it influences both the cost-effective selection of tubing and the development of an efficient production strategy, both of which are vital for maximizing oil recovery while minimizing operational expenses. To address this, our study proposes an innovative hybrid intelligent system designed to predict bottom-hole flowing pressure in vertical multiphase conditions with superior accuracy compared to existing methods using a data set of 150 field measurements amassed from Algerian fields. In this work, the applied hybrid framework is the Adaptive Neuro-Fuzzy Inference System (ANFIS), which integrates artificial neural networks (ANN) with fuzzy logic (FL). The ANFIS model was constructed using a subtractive clustering technique after data filtering, and then its outcomes were evaluated against the most widely utilized correlations and mechanistic models. Graphical inspection and error statistics confirmed that ANFIS consistently outperformed all other approaches in terms of precision, reliability, and effectiveness. For further improvement of the ANFIS performance, a particle swarm optimization (PSO) algorithm is employed to refine the model and optimize the design of the antecedent Gaussian memberships along with the consequent linear coefficient vector. The results achieved by the hybrid ANFIS-PSO model demonstrated greater accuracy in bottom-hole pressure estimation than the conventional hybrid approach. Full article

The prestressed concrete-filled double skin steel tube (CFDST) lattice tower has emerged as a promising structural solution for large-capacity wind turbine systems due to its superior load-bearing capacity and economic efficiency. The steel–concrete composite adapter (SCCA) is a key component that connects the upper tubular steel tower to the lower lattice segment, transferring axial loads. However, the compressive behaviour of the SCCA remains underexplored due to its complex multi-shell configuration and steel–concrete interaction. This study investigates the axial compression behaviour of SCCAs through refined finite element simulations, identifying diagonal extrusion as the typical failure mode. The analysis clarifies the distinct roles of the outer and inner shells in confinement, highlighting the dominant influence of outer shell thickness and concrete strength. A sensitivity-based parametric study highlights the significant roles of outer shell thickness and concrete strength. To address the high cost of FE simulations, a 400-sample database was built using Latin Hypercube Sampling and engineering-grade material inputs. Using this dataset, five neural networks were trained to predict SCCA capacity. The Dropout model exhibited the best accuracy and generalization, confirming the feasibility of physics-informed, data-driven prediction for SCCAs and outperforming traditional empirical approaches. A graphical prediction tool was also developed, enabling rapid capacity estimation and design optimization for wind turbine structures. This tool supports real-time prediction and multi-objective optimization, offering practical value for the early-stage design of composite adapters in lattice turbine towers. Full article

Streak cameras, essential for ultrahigh temporal resolution diagnostics in laser-driven inertial confinement fusion, underpin the streak tube imaging LiDAR (STIL) system—a flash LiDAR technology offering high spatiotemporal resolution, precise ranging, enhanced sensitivity, and wide field of view. This study establishes a theoretical model of the STIL system, with numerical simulations predicting limits of temporal and spatial resolutions of ~6 ps and 22.8 lp/mm, respectively. Dynamic simulations of laser backscatter signals from targets at varying depths demonstrate an optimal distance reconstruction accuracy of 98%. An experimental STIL platform was developed, with the key parameters calibrated as follows: scanning speed (16.78 ps/pixel), temporal resolution (14.47 ps), and central cathode spatial resolution (20 lp/mm). The system achieved target imaging through streak camera detection of azimuth-resolved intensity profiles, generating raw streak images. Feature extraction and neural network-based three-dimensional (3D) reconstruction algorithms enabled target reconstruction from the time-of-flight data of short laser pulses, achieving a minimum distance reconstruction error of 3.57%. Experimental results validate the capability of the system to detect fast, low-intensity optical signals while acquiring target range information, ultimately achieving high-frame-rate, high-resolution 3D imaging. These advancements position STIL technology as a promising solution for applications that require micron-scale depth discrimination under dynamic conditions. Full article

A physics-informed neural network (PINN) framework is developed to model the large deformation and coupled electromechanical response of dielectric elastomer tubes for energy harvesting. The system integrates incompressible neo-Hookean elasticity with radial electric loading and compressible gas inflation, leading to nonlinear equilibrium equations with deformation-dependent boundary conditions. By embedding the governing equations and boundary conditions directly into its loss function, the PINN enables accurate, mesh-free solutions without requiring labeled data. It captures realistic pressure–volume interactions that are difficult to address analytically or through conventional numerical methods. The results show that internal volume increases by over 290% during inflation at higher reference pressures, with residual stretch after deflation reaching 9.6 times the undeformed volume. The axial force, initially tensile, becomes compressive at high voltages and pressures due to electromechanical loading and geometric constraints. Harvested energy increases strongly with pressure, while voltage contributes meaningfully only beyond a critical threshold. To ensure stable training across coupled stages, the network is optimized using the Optuna algorithm. Overall, the proposed framework offers a robust and flexible tool for predictive modeling and design of soft energy harvesters. Full article

Folic acid supplementation during the periconceptional period is a well-established strategy to prevent neural tube defects (NTDs). However, emerging uncertainties surrounding optimal dosage, alternative folate forms, duration of use, and the role of genetic variability have sparked scientific and policy debates. In Brazil, these challenges are amplified by unique contextual factors, including the routine distribution of high-dose folic acid (5000 µg) through the public health system, social vulnerability, low adherence, and limited population-specific evidence for the country’s highly admixed population. This narrative review critically examined the scientific evidence and public health policies surrounding folic acid supplementation, with a focus on Brazil. We examined historical developments, international recommendations, and emerging controversies, including the emerging influence of misinformation. Despite the worldwide progress in NTD prevention, both local and global challenges persist, including delayed initiation, inconsistent adherence, and uncertainty regarding alternative supplementation regimens. Addressing these demands requires the development of context-specific guidelines, alongside coordinated strategies in provider training, public education, monitoring, and research investments to ensure effective, safe, and equitable folic acid supplementation. Full article

Gestational diabetes mellitus (GDM) affects approximately 14% of pregnancies globally and has been hypothesized to be influenced by periconceptional and early pregnancy folic acid (FA) supplementation, a practice recommended to prevent neural tube defects. To evaluate this association, we conducted a systematic review of studies published between 2015 and 2024 examining FA use and GDM risk. Twelve studies met the inclusion criteria, including ten cohort studies and two case-control studies. While findings were mixed, several prospective studies suggested that high daily FA intake (≥800 μg) or prolonged use (>3–6 months) may be associated with increased odds of GDM, especially when initiated preconceptionally. Conversely, standard-dose supplementation (≈400 μg) appeared neutral or potentially protective in some populations. Notably, high folate status combined with low vitamin B12 was linked to increased GDM risk, suggesting metabolic interaction. Overall, most studies were of moderate to high methodological quality. Although current evidence is inconclusive, these results support cautious use of high-dose FA supplementation and the importance of individualized prenatal nutrition, particularly considering B12 status. Further research is needed to clarify biological mechanisms. Full article

Background: Congenital anomalies impact 52 million infants worldwide with an estimated 94% living in low- and middle-income countries (LMICs). Approximately 200,000 children are born with a neural tube defect (NTD) in LMICs annually. Zambia is an LMIC with a high burden of myelomeningocele (MMC; a severe form of NTD). This study sought to characterize the barriers influencing access to healthcare for children born with MMC in Zambia. Methods: Two cross-sectional surveys were administered to healthcare providers at referring public health facilities and mothers of infants born with MMC undergoing surgical closure. The survey among mothers was nested in a longitudinal study evaluating surgical closure in Lusaka, Zambia from 28 May 2024 to 21 January 2025. Results: Sixty-nine mother–MMC baby dyads and 123 providers from 21 facilities were enrolled in the study. The median age at presentation for MMC was 7.5 (range 0–244) days old. Most patients were referred from rural district hospitals (51%; n = 35) and travelled greater than 250 km to access care (80%; n = 55). Seventy-seven percent (n = 53) of mothers reported receiving at least one antenatal ultrasound, with 62% (n = 43) undergoing an ultrasound after 20 weeks estimated gestational age. Of these, only 3% (n = 2) received an MMC diagnosis prior to delivery. Referring patients with MMC for further care greater than six hours after birth was reported by 59% providers (n = 73). Hospitals further away from the tertiary center were more likely to report late referrals (p < 0.001). Conclusions: There is a delay in the diagnosis and referral of infants with MMC to specialized care in Zambia, which may be attributed to inadequate in utero diagnosis capabilities and distance from the tertiary facility. Improving the accuracy of prenatal diagnosis and strengthening referral pathways to facilitate access to care among infants with MMC in Zambia are important for improving incidence and outcomes. Full article

Folate is an essential vitamin involved in one-carbon metabolism. It can be acquired from many food sources or in synthetic form. A wide range of processing methods have been studied to improve the bioaccessibility and bioavailability of folate in foods, yet this is often accompanied by a decrease in stability. Encapsulation technology has emerged as an effective solution for protecting folate from degradation and liberation while also improving its bioavailability. Folate deficiency is a prevalent phenomenon worldwide, particularly in underprivileged countries, leading to various health problems, such as neural tube defects. Thus, folate was fortified through both exogenous addition and biofortification. Gene editing technology, especially CRISPR-Cas9, has great promise in this field when compared to transgenic engineering, because transgenic engineering may pose safety concerns and environmental risks. While ongoing research has identified additional potential effects of folate, the dosage and duration remain important factors to consider for optimal health outcomes. The mechanisms of how folate promotes the production of neurotransmitters associated with the gut microbiota–brain axis and reduces depression are not well understood. In addition to folate alone, there may be synergistic effects of combined supplementation of folate and other nutrients or medications, but this is not yet fully clarified and requires further examination. This review summarizes the food sources, enrichment, bioaccessibility, and bioavailability of folate. Furthermore, the health benefits of folate, including neural tube protection, cardiovascular protection, neuroprotection, anti-cancer, immune response augmentation, and gut homeostasis maintenance, with their potential bioactivity mechanisms, are discussed. Full article