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Background: With the advent of outpatient total joint arthroplasty (TJA), the days of routinely drawing postoperative labs (complete blood counts [CBCs] and metabolic panels [CMPs/BMPs]) to monitor for complications are behind us. However, there does exist a subset of at-risk patients that may benefit from diligent postoperative monitoring, though the circumstances under which labs should be ordered remains unclear and subject to surgeon discretion. A systematic review of the literature was therefore conducted to evaluate the utility of postoperative laboratory testing, approaches to targeted patient selection and associated cost-savings. Methods: The PubMed, MEDLINE, EBSCOhost, and Google Scholar electronic databases were searched on August 17, 2023, to identify all studies published since January 1, 2000, that evaluated the role of postoperative lab testing in TJA. (PROSPERO study protocol registration: CRD42023437334). Articles were included if a full-text English manuscript was available and the study assessed the utility of routine postoperative labs in TJA. 19 studies were included comprising 34,166 procedures. The mean Methodological index for Nonrandomized Studies score was 18.2 ± 1.5. Results: Abnormal postoperative lab results were common and infrequently required clinical intervention. Among several identified risk factors for patients that may benefit from postoperative laboratory monitoring, preoperative lab values proved excellent discriminators of transfusion requirement and metabolite-associated intervention. Selective testing demonstrated the ability to generate substantial cost-savings. Conclusion: Routine postoperative laboratory testing offers little clinical utility and produces unnecessary expenditures. Preoperative lab values offer the greatest predictive utility for postoperative transfusion requirement and metabolite-associated clinical intervention, with a preoperative hemoglobin threshold of 111.5 g/L offering an area under the curve (AUC) of 0.93 for predicting postoperative transfusion. Further investigations are needed for metabolic panel predictive models and should incorporate preoperative lab values. The refinement of such models can enable targeted patient selection to avoid unnecessary labs and generate substantial cost savings without compromising patient safety.
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Rapid multiplex PCR kits have been used for rapid identification of blood culture isolates and prediction of antimicrobial resistance. We performed an evaluation of the QIAstat-Dx BCID GN and GPF research use only (RUO) kits on positive blood culture bottles using routine laboratory testing as the reference standard. Positive blood culture bottles between November 2023 and January 2024 were tested with QIAstat-Dx BCID GN and GPF kits based on initial Gram stain results and compared against routine identification and phenotypic susceptibility testing. A total of 174 monomicrobial blood cultures were included in the final analysis. The 174 monomicrobial blood cultures composed of 129 BCID GN tests and 45 BCID GPF tests. The majority of on-target Gram-negative organisms in monomicrobial cultures were identified. One Escherichia coli isolate was not identified as such, although the pan-Enterobacterales target was positive. All on-target Gram-positive organisms in monomicrobial cultures were identified. Overall sensitivity and specificity of tem/shv for detection of aminopenicillin resistance in E. coli was 94.7% (18/19) and 95.8% (23/24). The presence/absence of ctx-m and ampC had 100% sensitivity and specificity for identification of third-generation cephalosporin resistance in E. coli and Klebsiella pneumoniae. The combination of blaZ and mecA gene detection was fully predictive of phenotypic susceptibility results to penicillin and cloxacillin for Staphylococcus aureus. Overall, the QIAstat-Dx BCID GN and GPF kits were able to identify on-target pathogens. Detected resistance mechanisms were highly predictive of ß-lactam resistance. Prediction of resistance for non-ß-lactam antimicrobial was more variable. IMPORTANCE: This is one of the first evaluations of the QIAstat BCID kit and demonstrates high levels of correlation for both identification and antimicrobial resistance prediction.
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Aluminium foam sandwich panels (AFSPs) have a high impact resistance and are suitable for a wide range of engineering applications. To improve corrosion resistance, this paper proposes an anti-corrosion sandwich panel with stainless steel as the upper sheet. Drop hammer impact tests were performed on a total of ten AFSPs to investigate their dynamic response and failure patterns. To assess the deformation performance of AFSPs, a laser displacement meter was used to obtain the bottom centre displacement. The effects of the impact energy and the thickness of each component of AFSPs on the peak impact force and deformation performance were studied. Test results showed that the thickness of each component had notable effects on the impactor and bottom displacements. In addition, the effect of the unit mass of the components in AFSPs on decreasing the bottom displacement was discussed. Compared to increasing the aluminium foam and lower sheet thicknesses, increasing the upper sheet thickness was more effective in decreasing the bottom displacement. A finite element model of AFSPs was developed to conduct parameter analysis, indicating that impactors with larger diameters resulted in higher peak forces and reduced deformation of AFSPs.
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Stroke remains a leading cause of mortality and disability worldwide. Identifying reliable biomarkers for stroke diagnosis and risk prediction could significantly improve patient outcomes through earlier intervention and better risk management. The objective of this systematic review is to systematically review recent studies investigating biomarkers for stroke diagnosis and risk prediction and to synthesize the most promising findings. We conducted a systematic review of 10 studies published between 2008 and 2023 that examined various biomarkers in relation to stroke. Studies were evaluated for quality using a simplified version of the Mixed Methods Appraisal Tool. The reviewed studies investigated a diverse array of biomarkers, including lipids, inflammatory markers, hemodynamic markers, microRNAs, metabolites, and neurodegenerative markers. Key findings include the following: (1) non-traditional lipid markers such as triglycerides and non-high-density lipoprotein cholesterol may be more predictive of stroke risk than low-density lipoprotein; (2) inflammatory markers, particularly IL-6, showed strong associations with stroke risk; (3) hemodynamic markers like midregional proatrial natriuretic peptide (MRproANP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) demonstrated potential in distinguishing stroke subtypes; (4) specific microRNAs (miR-125a-5p, miR-125b-5p, miR-143-3p) were upregulated in acute ischemic stroke; (5) metabolomic studies identified novel markers such as tetradecanedioate and hexadecanedioate associated with cardioembolic stroke; (6) neurodegenerative markers (total-tau, neurofilament light chain) were linked to increased stroke risk. This review highlights the potential of various biomarkers in improving stroke diagnosis and risk prediction. While individual markers show promise, a multi-marker approach combined with clinical variables appears most likely to yield clinically useful tools. Further large-scale validation studies are needed before these biomarkers can be implemented in routine clinical practice.
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Purpose of review: This review explores the opportunities and challenges associated with using unconventional and underutilized wood sources, such as fast-growing species, logging residues, fire-damaged wood, and post-consumer wood, to manufacture wood-based composite panels (WBCPs), particularly particleboard, medium-density fiberboard (MDF), and oriented strand board. This paper also discusses recent advancements in lightweight and multifunctional panels, with new features such as fire resistance, electrical conductivity, electromagnetic shielding, and antibacterial laminates. Recent findings: Climate change, wildfires, and competition from the energy sector threaten current sources of fiber supply for WBCP manufacturing in some regions. Logging residues are abundant but underutilized in some areas, and the abundance of fire-damaged wood is expected to increase in the coming years due to climate change. These raw materials' effects on panel properties and technological limitations are discussed. Recycled wood is increasingly used for non-structural panels, but challenges remain when it comes to recycling panels, particularly post-consumer MDF. Conventional and emerging materials used in lightweight and multifunctional panels are also presented. Natural substances like cellulose, nanocellulose, chitosan, lignin, protein, and phytic acid are promising alternatives to conventional fire retardants. Innovative products such as MDF that contains carbon-based conductive fibers and antimicrobial laminates that use green-synthesized metal compounds are also reported. Summary: This review shows that the WBCP industry can improve its sustainability by optimizing and diversifying wood sources, better managing and recycling post-consumer panels, and using more environmentally friendly materials. The hazardous chemicals in adhesives, fire retardants, and coatings are the main obstacles to recycling panels and creating a more circular economy within the WBCP industry.
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In the context of close-distance coal seam mining, the stress transfer mechanism following the extraction of the upper coal seam is crucial for the layout of roadways in the lower coal seam. This study utilizes ground-penetrating radar (GPR) to analyze the stability and plastic zone extent of residual coal pillars after upper seam extraction. A theoretical model for the stress distribution of multiple goaves and coal pillars was established. Based on a case study with variable inter-seam spacing, the stress distribution and transfer mechanisms of the floor were analyzed. The results indicate that during the transition from the center of the coal pillar to the goaf, stress concentration initially decreases significantly and then gradually returns to the original rock stress, forming a distinct stress gradient distribution. As the depth of the floor strata increases, the weight of the overlying strata is more evidently transferred through the coal pillars to the goaf. Finally, a reasonable layout range for the lower seam mining roadways under different inter-seam spacings is proposed, providing a reference for optimizing roadway layout in similar geological conditions.
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Introduction: Appealing to individuals' social identity is a powerful form of social influence, capable of changing the way people process information, the information they think about, and how they evaluate other individuals. The purpose of this study is to explore the idea that Democrat and Republican environmental norms may impact the attributes and strategies partisans use when choosing whether to have solar panels on a house. Methods: An online study with N = 363 participants was conducted to examine these possible effects through multi-attribute decision making, applying predefined decision process models to participant behavior to test which attribute-based models best describe participants' decision making. A choice task was combined with an experimental manipulation of political affiliation salience to examine whether the norms of political groups would have influence on decision behavior. Results: Results of the study show remarkable similarities between political parties in their strategies for choosing solar panels. Members of both political parties appeared to use similar strategies and similar attributes for the formation of their decisions. Discussion: Recommendations are made that science communicators and policy makers avoid polarizing language so as not to create unnecessary polarization where ideological gaps may not currently exist.
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The International Human Papillomavirus (HPV) Reference Center launches annual global HPV genotyping proficiency panels to enhance the precision and international standardization of HPV genotyping services. This study aims to assess the proficiency levels achieved in the global HPV genotyping proficiency panels conducted in 2022 and 2023, and to evaluate trends in performance over time. The proficiency panels comprised 44 blinded samples each, including 40 samples containing various purified plasmids corresponding to HPV types combined with human DNA, plus four control samples (one negative control and three extraction controls). Proficiency required a sensitivity of 50 International Units (IU)/5 µL for HPV 16 and HPV 18 500 IU/5 µL for HPVs 6, 11, 31, 33, 45, 52, and 58 and 500 genome equivalents (GE)/5 µL for other HPV types in both single and multiple infections, while avoiding false positivity. In 2022, 78 laboratories submitted a total of 154 data sets, and in 2023, 81 laboratories contributed 141 data sets. Most data sets (87%, 258/295) utilized commercially available HPV assays. Proficiency was common, with 77% of data sets meeting the proficiency criteria in 2022 and 79% in 2023. False positive results significantly decreased from 22% in 2022 to 13% in 2023. The high proficiency and increasing specificity in HPV genotyping services indicates progress toward more reliable HPV testing. High accuracy is crucial for supporting global efforts in HPV and cervical cancer elimination.
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Genótipo , Técnicas de Genotipagem , Ensaio de Proficiência Laboratorial , Papillomaviridae , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/diagnóstico , Técnicas de Genotipagem/métodos , Técnicas de Genotipagem/normas , Papillomaviridae/genética , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Saúde Global , Sensibilidade e Especificidade , Papillomavirus HumanoRESUMO
This research introduces a novel hybrid system integrating solar drying, solar distillation, and photovoltaic thermal panels, aimed at drying agricultural products, producing clean drinking water, and conserving energy. The system enhances the drying air temperature using thermal energy storage materials and a solar dish concentrator connected to a hot water storage tank, ensuring continuous operation even after sunset. The solar distiller, equipped with energy storage materials and an air injection system, is integrated with an external condenser to condense water vapor before expulsion, thereby increasing freshwater productivity. The results revealed that the developed system achieved an accumulative freshwater productivity of 87.1 L per day. The rates of water removal from dried potato slices ranged from 0.18 to 0.91 kg/h between 8:00 am and 10:00 pm. Additionally, the system achieved a gain output ratio of 1.38, indicating a significant improvement in energy efficiency. This innovative system offers practical solutions to address energy and freshwater scarcity, especially in remote regions of the Middle East and North Africa (MENA) region, which are characterized by high solar irradiance. The implementation of such hybrid systems could contribute to sustainable development by reducing reliance on conventional energy sources and mitigating environmental pollution.
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The paper explains how nano exposure is assessed in the construction field and focuses on the production of fire-resistant insulation panels with nanoclay. Utilizing the commercial ANSYS CFX® software, a preliminary theoretical simulation was conducted on nano exposure in the workplace, which revealed that particle dispersion is primarily driven by diffusion. Panel post-processing through drilling results in the highest inhalation exposure, followed by mixing and grinding activities. Compared to a state of 'no activity', each activity resulted in an exposure increase by a factor of min. 1000. An overall assessment suggests that the use of nanoparticles in construction materials may not significantly heighten workers' exposure to nanopowders when considering particle concentration alone as opposed to using traditional micro-scale materials. However, the issue persists when it comes to blending powders or performing finishing tasks on panels, with concentration levels being significantly higher for drilling, grinding, and mixing powders at 2.4 times above the standard reference value (40,000 particles/cm3); this is unacceptable, even for brief durations. Examination of dermal contact with gloves and masks worn by workers revealed no nanoparticle penetration. Safety measures were proposed for workers based on decision trees to enhance their safety. Ten categories of protection strategies have been devised to combat the impact of nanoparticles, which are tailored to specific technical situations, but they must be modified for various types of nanoparticles despite potential shared health implications.
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The intricate encapsulation structure and material composition of photovoltaic modules necessitate full materials recycling involving multiple stages and different technological configurations, thereby increasing environmental burden of recycling process. Consequently, environmental impact assessments are imperative. However, previous studies primarily focused on a single technology or compared different technologies within a specific recycling stage, overlooking various technological configurations and thus engendering incomprehensive assessment. Hence, we employ a comparative life-cycle assessment to evaluate the environmental performance of six recycling alternatives with different technological configurations for silicon photovoltaic waste in China, which encompasses five recycling stages and glass/silicon remanufacturing processes. Results shows thermal delamination reduces the normalized environmental impact by 8.73% and 4.62% compared with mechanical and chemical delamination, respectively; electrolysis for metals extraction carries 35.72%-36.35% higher environmental benefits than precipitation. Additionally, introducing silicon/glass remanufacturing provides an additional 6.27%-11.55% environmental benefits. Therefore, integrating disassembly, thermal delamination, leaching & etching, electrolysis, and remanufacturing exhibits the best environmental performance, with -4796 kg CO2-eq/tonne carbon emission and -46400 MJ/tonne energy demand. Environmental hotspots analysis identifies key contributors to environmental impact and benefits. Further sensitivity analysis highlights the importance of enhancing silver and copper recovery efficiency. Finally, targeted strategies are proposed for green recycling routes of photovoltaic waste.
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Background: Respiratory infections are a major contributor to hospital admissions. Identification of respiratory pathogens by means of conventional culture and serology methods remains challenging. Multiplex molecular assays are an appealing alternative that endeavours to be rapid, more accurate and less arduous. Objective: The study aimed to compare the clinical performance of three commercial multiplex molecular assays for respiratory viruses. Methods: Forty-eight respiratory specimens obtained from patients at Tygerberg Hospital in the Western Cape province of South Africa were studied. These specimens were collected between May 2020 and August 2020. The results of the Seegene Anyplex™ II RV16, FilmArray® Respiratory 2.1 plus Panel (FARP), and QIAstat-Dx® Respiratory SARS-CoV-2 Panel (QRP) were analysed based on the overlapping targets. A composite reference standard was applied to provide a standard reference for comparison. Results: The overall sensitivity of the Seegene Anyplex™ II RV16 was 96.6% (57/59), the FARP 98.2% (56/57) and the QRP 80.7% (46/57). The overall specificities were 99.8% (660/661), 99.0% (704/711) and 99.7% (709/711), respectively. The QRP failed to detect coronaviruses and parainfluenza viruses in 41.7% (5/12) and 28.6% (4/14) of positive specimens, respectively, while the FARP produced the lowest target specificity of 88.4% (38/43) for rhinovirus/enterovirus. Conclusion: The overall specificity of all three platforms was comparable; however, the sensitivity of the QRP was inferior to that of the ARV and FARP. What this study adds: This study adds to the body of performance characteristics described for respiratory multiplex panels, especially in the African context where molecular diagnostics for infectious diseases are gaining momentum.
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The optimization of floating bifacial solar panels (FBS PV) in tropical freshwater systems is explored by employing response surface methodology (RSM) and central composite design (CCD). Previous studies have yet to explore the long-term durability, environmental impact, economic viability, and performance of FBS PV systems under various climatic conditions. This study addresses this gap by focusing on panel height, water depth, and tilt angle to improve performance. The quadratic model reveals significant non-linear relationships impacting FBS PV power generation with freshwater cooling. Our models demonstrate high explanatory power, with R-squared values of 0.9831 for output power and 0.9900 for Bi-Facial gain. Experimental validation using conventional white surface (CWS) and proposed freshwater surface (PFS) indicates notable improvements in power generation, achieving a 4.34 to 4.86% gain in bifacial efficiency across various irradiation levels. Under 950 W/m2 irradiation, freshwater cooling achieves a 3.19% higher bifacial gain compared to CWS cooling. Panel temperature analysis shows consistent reductions with freshwater cooling, ranging from 1.43 to 2.72 °C, enhancing overall efficiency and longevity. This research highlights the potential of freshwater cooling in optimizing bifacial solar systems, offering actionable insights for sustainable energy solutions in tropical regions.
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Since carbon fibre composite sandwich structures have high specific strength and specific modulus, which can meet the requirements for the development of aircraft technology, more and more extensive attention has been paid to their residual mechanical properties after subjecting them to fatigue loading in hygrothermal environments. In this paper, the compression and shear characteristics of carbon fibre-reinforced epoxy composite honeycomb sandwich wall panels after fatigue in hygrothermal environments are investigated through experiments. The experimental results show that under compressive loading, the load required for the buckling of composite honeycomb sandwich wall panels after fatigue loading in hygrothermal environments decreases by 25.9% and the damage load decreases by 10.5% compared to those at room temperature. Under shear loading, the load required for buckling to occur is reduced by 26.2% and the breaking load by 12.2% compared to those at room temperature.
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To reduce land use and avoid further pollution, incineration for power generation has become the main method for municipal solid waste treatment. This research focused on the potential for transforming Municipal Solid Waste Incineration Bottom Ash (MSWIBA) into a finely ground powder. The impact of the powder's fineness and the amount of water used on its effectiveness was analyzed using a method called grey theory. MSWIBA was used as a partial substitute for cement in making MSWIBA foam concrete and lightweight wall panels. By modifying the fineness and water utilization of the recycled micro-powder, its maximum activity index can be increased to 90.1. This study determined the influence of factors including apparent dry density, water-cement ratio, foaming agent dilution ratio, and admixture dosage on the strength of the recycled foam concrete, and established the optimal mix ratio. This study employed a combination of physical experiments and numerical simulations to elucidate the impact of panel material, core layer thickness, and layer sequence on sound insulation performance. The simulation results were in close agreement with the experimental findings.
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Feline respiratory disease complex (FRDC) is a highly prevalent syndrome in cats that often result in fatal outcomes. FRDC etiology is complex, and often, multiple viral and bacterial pathogens are simultaneously associated with disease causation. There is limited information about the role of co-infections in pathogenesis and the current prevalence of pathogens in North America. We aimed to conduct a study using technical advances in molecular diagnosis and statistical modeling analysis to elucidate the occurrence of pathogens and how co-infections affect disease severity. We attained information from three diagnostic laboratories in North America regarding the occurrence of Bordetella bronchiseptica, Chlamydia felis, Mycoplasma, Felid alphaherpesvirus 1 (FeHV-1), feline calicivirus (FCV), and influenza A, along with age, seasonality, sex, and clinical signs. We also evaluated the role of co-infections in disease severity. These pathogens were also investigated in clinically normal cats (control). The most detected pathogens were Mycoplasma, FCV, and FeHV-1. Most pathogens were detected in the control group, highlighting the challenge of interpreting positive testing results. Co-infections of Mycoplasma and FCV, as well as Mycoplasma and FeHV-1, were important predictors of disease severity. Age, sex, and season had a minor impact on pathogen occurrence. This study provides new insights into FRDC and underlines the relevance of diagnostic panels to screen for a range of pathogens, providing knowledge for timely diagnosis and therapeutic interventions.
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Purpose of Review: Conventional formaldehyde-based adhesives for wood-based composite panels are subject to significant concerns due to their formaldehyde emissions. Over the past decade, the wood adhesive industry has undergone a considerable transformation that is characterized by a major push in bio-adhesive development. Various bio-based materials have been explored to create alternatives to conventional formaldehyde-based adhesives. Moreover, growing interest in circularity has led to increasingly exploiting industrial coproducts and by-products to find innovative solutions. Recent Findings: Industrial production generates many coproducts that can serve as renewable resources to produce eco-friendly materials. These coproducts offer alternative supply sources for material production without encroaching on food production. Many bio-based compounds or coproducts, such as saccharides, proteins, tannins, and lignocellulosic biomass, can also be used to develop bio-based adhesives. As part of ongoing efforts to reduce formaldehyde emissions, new hardeners and crosslinkers are being developed to replace formaldehyde and bio-scavengers. Other alternatives, such as binderless panels, are also emerging. Summary: This review focuses on sources of bio-based material derived from by-products of various industries, which have many advantages and disadvantages when incorporated into adhesives. Modification methods to enhance their properties and performance in wood-based panels are also discussed. Additionally, alternatives for developing low-emission or formaldehyde-free adhesives are addressed, including hardeners, bio-scavengers, and binderless options. Finally, the environmental impact of bio-based adhesives compared to that of synthetic alternatives is detailed.
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OBJECTIVE: The objective of this study is to report the results of the genetic analysis in a large and well-characterized population with pediatric-onset epilepsies and to identify those who could benefit from precision medicine treatments. METHODS: In this retrospective observational study, we consecutively recruited patients with pediatric-onset epilepsy observed at a tertiary neurological center over a time span of 7 years, collecting clinical and laboratory findings. Following in-depth diagnostic process to exclude possible structural and metabolic causes of the disease, patients with a suspected genetically determined etiology underwent next-generation sequencing (NGS) screening with panels for the analysis of target genes causative of epilepsy. RESULTS: We detected likely pathogenic or pathogenic variants (classes IV and V) in 24% of the 562 patients who underwent genetic investigations. By the evaluation of patients' data, we observed that some features (onset of epilepsy before one year old, presence of neurological deficits, psychomotor delay/cognitive disability, and malformative aspects at brain MRI) were significantly associated with class IV or V variants. Moreover, statistical analysis showed that the diagnostic yield resulted higher for patients affected by Progressive Myoclonic Epilepsy (PME) and with early onset developmental and epileptic encephalopathies (DEE), compared with focal epilepsies, genetic generalized epilepsies, DEE with onset at/after 1 y.o., and unclassified epileptic syndromes. According to the results of the genetic screening, up to 33% of patients carrying class IV or V variants resulted potentially eligible for precision medicine treatments. SIGNIFICANCE: The large-scale application of NGS multigene panels of analysis is a useful tool for the molecular diagnosis of patients with pediatric-onset epilepsies, allowing the identification of those who could benefit from a personalized therapeutic approach. PLAIN LANGUAGE SUMMARY: The analysis of patients with pediatric-onset epilepsy using advanced technologies for the screening of all the implicated genes allows the identification of the cause of diseases in an ever-increasing number of cases. Understanding the pathogenic mechanisms could, in some cases, guide the selection and optimization of appropriate treatment approaches for patients.
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Epilepsia , Sequenciamento de Nucleotídeos em Larga Escala , Medicina de Precisão , Humanos , Criança , Feminino , Masculino , Estudos Retrospectivos , Epilepsia/genética , Epilepsia/diagnóstico , Pré-Escolar , Adolescente , Lactente , Testes Genéticos , Idade de InícioRESUMO
In this study, a numerical dynamic analysis of ceiling raster panels was performed. The analysis was conducted on panels designed with inspiration from bionics. The purpose of the analysis was to enable optimisation of the location of the holes in the designed slabs in order to achieve the preferred dynamic properties, including the natural frequencies of the slabs and an appropriate airflow to avoid the occurrence of resonance. Three different types of panels were used and a total of fifteen panels were designed in terms of their geometry, with circular, elliptical, and hexagonal perforations, made of different materials: polypropylene PP, wood, and aluminium. Then, using the finite element method and ANSYS 2023 R1 software, the airflow over the ceiling panels and their natural frequencies and vibration modes were analysed. The analysis took into account not only the shape of the openings, but also their percentage area relative to the total panel area and different airflow velocities. In addition, the results were compared in an analytical way with those obtained for a solid slab. The results obtained include findings on the mode shapes and values of the vibration frequencies of the plates, air pressure maps, histograms, and plots of the pressure dependence on the surface area of the plate openings.
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Multiannual population cycles of small mammals are of interest within population biology. We propose an approach for multidimensional autoregressive (AR) time series and analyse monitoring data on grey-sided voles (Myodes rufocanus) in Japan to investigate one or possibly multiple multiannual cycles that drive population dynamics. Temperature, through modifying rodent communities, is found to be a key factor shaping population dynamics. Warmer areas are the main habitat for other rodent species resulting in low vole abundance/dominance, as opposed to higher vole dominance in colder areas-a pattern associated with the AR structure and population cycle. Vole populations in simple rodent communities exhibit an AR(2) cycle of 2-3 years. In areas with complex rodent communities, vole dynamics follows an AR(4) process and a combination of two cycles with different lengths. The AR structure varies in relatively small spatial scales, thus widening the scope of AR analyses needed. Historically, vole abundance increased in the late 1970s and decreased from the 1980s, with warm winters shown to be associated with the decline of vole abundance in the AR(4) populations. This significant association between the AR order, population dynamics, temperature and rodent community provides insights into the declining trends observed in rodent populations of the Northern Hemisphere.