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1.
Nat Commun ; 15(1): 3990, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734685

RESUMO

The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.

2.
bioRxiv ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38586026

RESUMO

Molecular control of recovery after exercise in muscle is temporally dynamic. A time course of biopsies around resistance exercise (RE) combined with -omics is necessary to better comprehend the molecular contributions of skeletal muscle adaptation in humans. Vastus lateralis biopsies before and 30 minutes, 3-, 8-, and 24-hours after acute RE were collected. A time-point matched biopsy-only group was also included. RNA-sequencing defined the transcriptome while DNA methylomics and computational approaches complemented these data. The post-RE time course revealed: 1) DNA methylome responses at 30 minutes corresponded to upregulated genes at 3 hours, 2) a burst of translation- and transcription-initiation factor-coding transcripts occurred between 3 and 8 hours, 3) global gene expression peaked at 8 hours, 4) ribosome-related genes dominated the mRNA landscape between 8 and 24 hours, 5) methylation-regulated MYC was a highly influential transcription factor throughout the 24-hour recovery and played a primary role in ribosome-related mRNA levels between 8 and 24 hours. The influence of MYC in human muscle adaptation was strengthened by transcriptome information from acute MYC overexpression in mouse muscle. To test whether MYC was sufficient for hypertrophy, we generated a muscle fiber-specific doxycycline inducible model of pulsatile MYC induction. Periodic 48-hour pulses of MYC over 4 weeks resulted in higher muscle mass and fiber size in the soleus of adult female mice. Collectively, we present a temporally resolved resource for understanding molecular adaptations to RE in muscle and reveal MYC as a regulator of RE-induced mRNA levels and hypertrophy.

3.
Bio Protoc ; 13(24): e4900, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38156031

RESUMO

Streamlined procedures for processing and cryopreservation of cell therapies using good laboratory practices are integral to biomanufacturing process development and clinical applications. The protocol herein begins with the preparation of human cell types cultured as adherent (i.e., mesenchymal stromal cells, MSCs) or suspension cells (i.e., peripheral blood mononuclear cells, PBMCs) to comprehensively demonstrate procedures that are applicable to commonly used primary cell cultures. Cell processing steps consist of preparing high yields of cells for cryopreservation using instruments routinely used in cell manufacturing, including the Finia® Fill and Finish System and a controlled-rate freezer. The final steps comprise the storage of cells at subzero temperatures in liquid nitrogen vapor phase followed by the analysis of cell phenotypes before and after processing and cryopreservation, along with cell quality metrics for validation. Additionally, the protocol includes important considerations for the implementation of quality control measures for equipment operation and cell handling, as well as Good Laboratory Practices for cell manufacturing, which are essential for the translational use of cell therapies. Key features • The protocol applies to small- or large-scale manufacturing of cell therapy products. • It includes streamlined procedures for processing and cryopreservation of cells cultured as adherent cells (MSCs) and suspension cells (PBMCs). • Provides temperature control and rapid partitioning of sample in cryopreservation solution to maintain high viability of a range of cell types throughout the procedures. • This protocol employs the Finia® Fill and Finish System and a controlled-rate freezer. Graphical overview.

4.
Phys Rev Lett ; 129(20): 205001, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36461991

RESUMO

Experiments on the DIII-D tokamak have identified a novel regime in which applied resonant magnetic perturbations (RMPs) increase the particle confinement and overall performance. This Letter details a robust range of counter-current rotation over which RMPs cause this density pump-in effect for high confinement (H mode) plasmas. The pump in is shown to be caused by a reduction of the turbulent transport and to be correlated with a change in the sign of the induced neoclassical transport. This novel reversal of the RMP induced transport has the potential to significantly improve reactor relevant, three-dimensional magnetic confinement scenarios.

5.
Cureus ; 14(11): e31171, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36505178

RESUMO

Sarcoidosis is a well-characterized inflammatory disease that affects multiple organ systems and can have long-term devastating outcomes if not identified and treated appropriately. The disease is most prevalent among young to middle-aged African American women. It most commonly presents with pulmonary involvement, though there are reported cases of sarcoidosis without pulmonary involvement. Pulmonary presentations can be biopsied, diagnosed, and treated with primary immunomodulation with great treatment success. Here, we present an unusual presentation of sarcoidosis as granulomatosis mucositis in the salivary gland and concurrent rare complication of sarcoid myositis in the rectus femoris in a patient with no evidence of pulmonary involvement throughout the duration of their clinical course. Further, we discuss differential diagnoses related to this patient's presentation as well as the efficacy of treatment modalities available in the management of this disease.

6.
Rev Sci Instrum ; 93(9): 093528, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182482

RESUMO

A time domain algorithm has been developed to remove the vacuum pickup generated by both coil current (DC) and induced vessel current (AC) in real time from three dimensional (3D) magnetic diagnostic signals in the National Spherical Torus Experiment-Upgrade (NSTX-U) and DIII-D tokamaks. The possibility of detecting 3D plasma perturbations in real time is essential in modern and future tokamaks to avoid and control MHD instabilities. The presence of vacuum field pickup, due to toroidally asymmetric (3D) coils or to misalignment between sensors and axisymmetric (2D) coils, pollutes the measured plasma 3D field, making the detection of the magnetic field produced by the plasma challenging. Although the DC coupling between coils and sensors can be easily calculated and removed, the AC part is more difficult. An algorithm based on a layered low-pass filter approach for the AC compensation and its application for DIII-D and NSTX-U data is presented, showing that this method reduces the vacuum pickup to the noise level. Comparison of plasma response measurements with and without vacuum compensation shows that accurate mode locking detection and plasma response identification require precise AC and DC compensations.

8.
Environ Sci Technol ; 56(19): 13719-13727, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36137535

RESUMO

Carbon black (CB) is a nanomaterial with numerous industrial applications and high potential for integration into nano-enabled water treatment devices. However, few analytical techniques are capable of measuring CB in water at environmentally relevant concentrations. Therefore, we intended to establish a quantification method for CB with lower detection limits through utilization of trace metal impurities as analytical tracers. Various metal impurities were investigated in six commercial CB materials, and the Monarch 1000 CB was chosen as a model for further testing. The La impurity was chosen as a tracer for spICP-MS analysis based on measured concentration, low detection limits, and lack of polyatomic interferences. CB stability in water and adhesion to the spICP-MS introduction system presented a challenge that was mitigated by the addition of a nonionic surfactant to the matrix. Following optimization, the limit of detection (64 µg/L) and quantification (122 µg/L) for Monarch 1000 CB demonstrated the applicability of this approach to samples expected to contain trace amounts of CB. When compared against gravimetric analysis and UV-visible absorption spectroscopy, spICP-MS quantification exhibited similar sensitivity but with the ability to detect concentrations an order of magnitude lower. Method detection and sensitivity was unaffected when dissolved La was spiked into CB samples at environmentally relevant concentrations. Additionally, a more complex synthetic matrix representative of drinking water caused no appreciable impact to CB quantification. In comparison to existing quantification techniques, this method has achieved competitive sensitivity, a wide working range for quantification, and high selectivity for tracing possible release of CB materials with known metal contents.


Assuntos
Água Potável , Fuligem , Espectrometria de Massas/métodos , Metais , Tamanho da Partícula , Tensoativos
9.
Int J Bullying Prev ; : 1-13, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35935737

RESUMO

The current study examined the role of moral disengagement in cyberbullying participant role behavior among college-aged individuals. Participants included 434 students who completed surveys measuring their participation in cyberbullying, including online bystander role behaviors, as well as their moral disengagement. Regression analysis results indicated that moral disengagement was positively associated with cyberbullying perpetration, cyberbullying victimization, passive bystanding online behavior, and reinforcing online behavior. The current study furthers knowledge on the associations between online bullying-related behavior and moral disengagement and could lead to necessary cyberbullying prevention and intervention support for young adults.

10.
J Pediatr Nurs ; 65: e115-e125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35484005

RESUMO

Pediatric obesity has become a major health care concern over the last several decades. This condition can lead to detrimental life-long physical and mental comorbidities. Pediatric primary care providers have a unique opportunity to both prevent and treat pediatric obesity in their clinics. However, discussing this topic with families can be uncomfortable and time consuming. Time efficient resources to educate and increase confidence are needed to improve the management of pediatric obesity. This quality improvement project integrated the Healthy Care for Healthy Kids by the National Institute for Children's Healthcare Quality (2014) into the electronic medical record at a pediatric primary care office in rural East Tennessee. This toolkit included handouts, management algorithms, and provider education for pediatric obesity. After an 8-week implementation period, improvements in lab draws and evaluation of a family''s readiness to change were noted. Overall, providers reported the toolkit was helpful and improved patient interaction. Currently, the clinic is still utilizing the integrated resources and handouts.


Assuntos
Obesidade Infantil , Criança , Atenção à Saúde , Humanos , Obesidade Infantil/prevenção & controle , Atenção Primária à Saúde , Melhoria de Qualidade , Qualidade da Assistência à Saúde
11.
SN Appl Sci ; 5: 1-12, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-37383926

RESUMO

Fused filament fabrication is a 3D printing technique that has gained widespread use from homes to schools to workplaces. Thermoplastic filaments, such as acrylonitrile-butadiene-styrene (ABS) and polylactic acid (PLA), are extruded at temperatures near their respective glass transition temperature or melting point, respectively. Little has been reported on the inorganic elemental composition and concentrations present in these materials or the methods available for extracting that information. Because inorganic constituents may be included in the aerosolized particulates emitted during the printing process, identifying elements that could be present and at what specific concentrations is critical. The objective of the current research is to determine the range of metals present in thermoplastic filaments along with their relative abundance and chemical speciation as a function of polymer type, manufacturer, and color. A variety of filaments from select manufacturers were digested using a range of techniques to determine the optimal conditions for metal extraction from ABS and PLA polymers. The extraction potential for each method was quantified using by ICP-MS analysis. When possible, further characterization of the chemical composition of the filaments was investigated using X-ray Absorption spectroscopy to determine chemical speciation of the metal. Optimal digestion conditions were established using a high temperature, high pressure microwave-assisted acid digestion method to produce the most complete and repeatable extraction results. The composition and abundance of metals in the filaments varied greatly as a function of polymer, manufacturer, and color. Potential elements of concern present in the filaments at elevated concentration included that could pose a respiratory risk included Si, Al, Ti, Cu, Zn, and Sn. XAS analysis revealed a mixture of metal oxides, mineral, and organometallic compounds were present in the filaments that were being used to increase opaqueness impart color (dyes), polymeric catalysts, and flame retardants. This work shows that a variety of metals are present in the starting materials used for 3D printing and depending on their partitioning into 3D printed products and byproducts as well as the exposure route, may pose a health risk which merits further investigation.

12.
J Sch Psychol ; 89: 72-90, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34836577

RESUMO

Students often hear their peers use biased language regarding race, religion, sexual orientation, or disability status in the school setting. Prior research has indicated that biased language is related to school climate, and specifically to school-based relationships between peers and between students and their teachers. This study investigated the longitudinal associations among student-student relationships, teacher-student relationships, and being the target of or hearing biased language in middle school students. Students (N = 501; 46.5% White, 21.8% Hispanic, 13% African American, and 15% Multi-Racial; 48.7% female) reported on how much they were targeted or heard biased language related to race/religion, sexual orientation, and disability status. Students also reported on their relationships with their peers and teachers. Using a cross-lagged panel model with the overall sample, a negative unidirectional association from being the target of or hearing biased language and student-student relationships and teacher-student relationships was identified. Separate models for boys and girls identified unique patterns. For boys, biased-language exposure predicted more negative student-student relationships and teacher-student relationships, whereas for girls, biased-language exposure was not associated with school-based relationships. Implications include addressing language use and building positive student-student and teacher-student relationships.


Assuntos
Relações Interpessoais , Idioma , Feminino , Humanos , Masculino , Grupo Associado , Professores Escolares , Instituições Acadêmicas , Estudantes
13.
Rev Sci Instrum ; 92(7): 073504, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340450

RESUMO

Optimizing the differential pair connection scheme (i.e., the set of pairs) of a toroidal array of magnetic sensors dedicated to measuring slowly rotating asymmetric fields can enhance the mode number detection capability and failure-resilience. In this work, the condition number obtained from singular value decomposition of the design matrix is used as a metric to evaluate the quality of a connection scheme. A large number of possible pair connections are usually available, so evaluating all of them may require extensive use of computational resources and can be very time-consuming. Alternative methods to reduce the number of pairs evaluated without losing the capabilities of toroidal mode detection are presented in this paper. Three examples of the applications of such analysis for the 3D magnetic diagnostic system of DIII-D are also presented: the addition of two new toroidal arrays with n > 3 detection capabilities, the modification of an existing toroidal array in the low field side of the machine to accommodate the addition of a helicon antenna, and the design of changes in several toroidal arrays in the high field side to accommodate the addition of a lower hybrid current drive antenna on the center post.

14.
Phys Rev Lett ; 127(5): 055002, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397254

RESUMO

We report the experimental observation of seed magnetic island formation by nonlinear three-wave coupling of magnetic island triplets. In this experiment, disruptive 2,1 islands are seeded by the coupling of 4,3 and 3,2 tearing modes to a central 1,1 sawtooth precursor. Three-wave interactions between these modes are conclusively identified by bispectral analysis, indicating fixed phase relationships in agreement with theory. This new observation of this seeding mechanism has important implications for future reactors that must operate in stable plasma equilibria, free of disruptive 2,1 islands.

15.
Rev Sci Instrum ; 92(4): 043516, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243478

RESUMO

Given spatially resolved measurements of normal and tangential components of the magnetic field just outside the surface of a magnetically confined plasma, the field at the measurement location can be uniquely decomposed into contributions from the plasma and from external sources. This principle allows direct measurement of the electromagnetic torque on the plasma without knowledge of the distribution of the internal and external currents, similar to the more well-known formalism using the Maxwell stress tensor. The internal/external field decomposition also enables a mixed approach that incorporates any explicitly known current distributions (e.g., from non-axisymmetric coils). We discuss the requirements and limitations of such an approach to torque measurements. Experimental measurements of the torque evolution as a rotating tearing mode locks to the wall in the DIII-D tokamak are consistent with a simple model.

16.
J Sch Psychol ; 86: 49-63, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34051917

RESUMO

Although some research has evidenced a negative association between involvement in bullying and academic performance, more work is needed to understand the associations between academic performance and involvement in a more comprehensive range of bully role behaviors. The goals of the current study were to determine (a) the associations among a broader range of bully role behaviors (i.e., bullying, assisting, victimization, defending, and outsider behavior) and academic performance (i.e., grade point average; GPA), and (b) gender differences within these associations. The current study investigated these issues over the course of an academic year with 7794 students in middle through high school. Bullying behaviors were assessed in the fall and GPA data were gathered from school records from the spring of the same academic year. The results identified significant negative associations between bullying (b = -0.07, p = .001), assisting (b = -0.16, p < .001), victimization (b = -0.06, p < .001), and defending (b = -0.04, p < .001) with student GPA, whereas no significant association emerged for outsider behavior and GPA (b = -0.02, p = .13). In addition, several gender differences were found in these associations, including a stronger negative association between assisting and GPA for girls (b = -0.23, p = .001) than for boys (b = -0.08, p = .014) and a significant negative association between victimization and GPA for girls (b = -0.09, p < .001), but not boys (b = -0.02, p = .117). Differences in results across schools were also examined in an exploratory manner. The educational impact associated with bullying behaviors, limitations of the current study, and suggestions for future research are discussed.


Assuntos
Desempenho Acadêmico , Bullying , Vítimas de Crime , Feminino , Humanos , Masculino , Instituições Acadêmicas , Inquéritos e Questionários
17.
Phys Rev Lett ; 126(12): 125001, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33834790

RESUMO

Predictive 3D optimization reveals a novel approach to modify a nonaxisymmetric magnetic perturbation to be entirely harmless for tokamaks, by essentially restoring quasisymmetry in perturbed particle orbits as much as possible. Such a quasisymmetric magnetic perturbation (QSMP) has been designed and successfully tested in the KSTAR and DIII-D tokamaks, demonstrating no performance degradation despite the large overall amplitudes of nonaxisymmetric fields and strong response otherwise expected in the tested plasmas. The results indicate that a quasisymmetric optimization is a robust path of error field correction across the resonant and nonresonant field spectrum in a tokamak, leveraging the prevailing concept of quasisymmetry for general 3D plasma confinement systems such as stellarators. The optimization becomes, in fact, a simple eigenvalue problem to the so-called torque response matrices if a perturbed equilibrium is calculated consistent with nonaxisymmetric neoclassical transport.

19.
Sci Total Environ ; 753: 141945, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32911165

RESUMO

Global climate change continues to cause alterations in environmental conditions which can be detrimental to aquatic ecosystem health. The development of pesticide resistance in organisms such as Hyalella azteca can lead to increased susceptibility to environmental change. This research provides a robust assessment of the effects of alterations in salinity on the fitness of H. azteca. Full-life cycle bioassays were conducted with non-resistant and pyrethroid-resistant H. azteca cultured under two salinity conditions representing a rise from freshwater control (0.2 psu) to increased salinity due to salt-water intrusion, reduced snowpack and evaporative enrichment (6.0 psu). Additionally, the upper thermal tolerance was defined for each population at each salinity. Pyrethroid-resistant H. azteca exhibited reduced thermal tolerance; however, they produced more offspring per female than non-resistant animals. Compared to the low salinity water, both non-resistant and pyrethroid-resistant H. azteca produced more offspring, grew larger (based on dry mass), and produced larger offspring in elevated salinity, although pyrethroid-resistant animals had lower survival and lipid levels. This study provides fundamental information about the fitness potential of H. azteca in a changing climate, suggesting advantages for non-resistant animals under future climate scenarios. In addition, this research further supports the need to consider the effects of global climate change when conducting risk assessment of contaminants of concern, as well as the contribution of contaminants when investigating climate change impacts on populations, as exposure may contribute to niche contraction.


Assuntos
Anfípodes , Inseticidas , Poluentes Químicos da Água , Animais , Mudança Climática , Ecossistema , Feminino , Inseticidas/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Sci Total Environ ; 743: 140845, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758854

RESUMO

Detection of metal nanoparticles (NPs) in the environment is an analytical challenge of interest due to increasing use of nanomaterials in consumer and industrial products. Detecting NPs associated with human activities is affected by both the magnitude and variation in background concentrations of natural NPs. In this work, we investigated the potential release of titanium dioxide (TiO2) NPs from sunscreen in three recreational rivers, with a time-intensive sampling regime on one river, in order to determine the range and variability of natural, background titania (Ti). Conventional ICP analysis for total metal concentrations, single particle ICP-MS for NP concentrations, and electron microscopy aided in assessing mineralogical morphology and composition. Oxybenzone, a widely-used organic sunscreen, was measured and used as a surrogate for the intensity of recreational activity in the water. Statistically significant increases in Ti concentrations were observed in Clear Creek, CO during one recreation period, but the significance of other instances of recreation-associated Ti increases was unclear, in part due to storm impacts on the natural suspended sediment load of the stream. A comparison of three recreational rivers showed increases in both Ti mass concentrations and NP sizes occur during recreation in both Clear Creek, CO and the Salt River, AZ, but no detectable changes in the Truckee River, NV. However, size distributions were variable in background samples, which make the significance of differences observed during recreation unclear. These results underline that the release of engineered nanoparticles to a natural system cannot be detected without a well-defined background, including measures of its variability during the study period.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Poluentes Químicos da Água/análise , Humanos , Rios , Protetores Solares/análise , Titânio/análise
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