bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of stress response distribution in patients with lateral ankle ligament injuries: a study of neural control strategies utilizing predictive computing models
Authors: Zhou Zhifeng , Zhou Huiyu , Jie Tianle , Xu Datao , Teo Ee-Chon , Wang Meizi , Gu Yaodong
Published: July 2024

Background

Ankle sprains are prevalent in sports, often causing complex injuries to the lateral ligaments. Among these, anterior talofibular ligament (ATFL) injuries constitute 85%, and calcaneofibular ligament (CFL) injuries comprise 35%. Despite conservative treatment, some ankle sprain patients develop chronic lateral ankle instability (CLAI). Thus, this study aimed to investigate stress response and neural control alterations during landing in lateral ankle ligament injury patients.

Method

This study recruited twenty individuals from a Healthy group and twenty CLAI patients performed a landing task using relevant instruments to collect biomechanical data. The study constructed a finite element (FE) foot model to examine stress responses in the presence of laxity of the lateral ankle ligaments. The lateral ankle ligament was modeled as a hyperelastic composite structure with a refined representation of collagen bundles and ligament laxity was simulated by adjusting material parameters. Finally, the validity of the finite element model is verified by a high-speed dual fluoroscopic imaging system (DFIS).

Result

CLAI patients exhibited earlier Vastus medialis (p < 0.001) and tibialis anterior (p < 0.001) muscle activation during landing. The FE analysis revealed that with laxity in the ATFL, the peak von Mises stress in the fifth metatarsal was 20.74 MPa, while with laxity in the CFL, it was 17.52 MPa. However, when both ligaments were relaxed simultaneously, the peak von Mises stress surged to 21.93 MPa. When the ATFL exhibits laxity, the CFL is subjected to a higher stress of 3.84 MPa. Conversely, when the CFL displays laxity, the ATFL experiences a peak von Mises stress of 2.34 MPa.

Conclusion

This study found that changes in the laxity of the ATFL and the CFL are linked to shifts in metatarsal stress levels, potentially affecting ankle joint stability. These alterations may contribute to the progression towards CLAI in individuals with posterolateral ankle ligament injuries. Additionally, significant muscle activation pattern changes were observed in CLAI patients, suggesting altered neural control strategies post-ankle ligament injury.
Identification of the histone acetyltransferase gene family in the Artemisia annua genome
Authors: Guo Yang , You Yan , Chen Furong , Liao Yong
Published: July 2024

As the most effective therapeutic drug for malaria, artemisinin can only be extracted from Artemisia annua L., which is sensitive to the surrounding growing habitat. Histone acetyltransferases (HATs) contain acetyl groups, which modulate mRNA transcription and thereby regulate plant environmental adaptation. Comprehensive analyses of HATs have been performed in many plants, but systematic identification of HATs in medicinal plants is lacking. In the present study, we identified 11 AaHATs and characterized these genes into four classes according to their conserved protein structures. According to the phylogenetic analysis results, potential functions of HAT genes from Arabidopsis thaliana, Oryza sativa, and A. annua were found. According to our results, AaHAT has a highly conserved evolutionary history and is rich in highly variable regions; thus, AaHAT has become a comparatively ideal object of medical plant identification and systematic study. Moreover, motifs commonly present in histone acetyltransferases in the A. annua genome may be associated with functional AaHATs. AaHATs appear to be related to gene-specific functions. AaHATs are regulated by cis-elements, and these genes may affect phytohormone responsiveness, adaptability to stress, and developmental growth. We performed expression analyses to determine the potential roles of AaHATs in response to three environmental stresses. Our results revealed a cluster of AaHATs that potentially plays a role in the response of plants to dynamic environments.
Mapping of dynamic quantitative trait loci for plant height in a RIL population of foxtail millet (Setaria italica L.)
Authors: Han Kangni , Wang Zhilan , Shen Lin , Du Xiaofen , Lian Shichao , Li Yuxin , Li Yanfang , Tang Chuchu , Li Huixia , Zhang Linyi , Wang Jun
Published: July 2024

Plant height (PH) is a crucial trait for strengthening lodging resistance and boosting yield in foxtail millet. To identify quantitative trait loci (QTL) and candidate genes associated with PH, we first developed a genetic map using a recombinant inbred line (RIL) population derived from a cross between Aininghuang and Jingu 21. Then, PH phenotyping data and four variations of best linear unbiased prediction (BLUP) were collected from nine environments and three development stages. Next, QTL mapping was conducted using both unconditional and conditional QTL methods. Subsequently, candidate genes were predicted via transcriptome analysis of parental samples at three developmental stages. The results revealed that the genetic map, based on re-sequencing, consisted of 4,360 bin markers spanning 1,016.06 cM with an average genetic distance of 0.23 cM. A total of 19 unconditional QTL, accounting for 5.23%–35.36% of the phenotypic variation explained (PVE), which included 7 major and 4 stable QTL, were identified. Meanwhile, 13 conditional QTL, explaining 5.88%–40.35% of PVE, including 5 major and 3 stable QTL, were discovered. Furthermore, four consistent and stable QTL were identified. Finally, eight candidate genes were predicted through RNA-seq and weighted gene co-expression network analysis (WGCNA). Those findings provide a crucial foundation for understanding the genetic mechanisms underlying PH development and facilitate molecular marker-assisted breeding of ideal plant types in foxtail millet.
Exercise motivation, physical exercise, and mental health among college students: examining the predictive power of five different types of exercise motivation
Authors: Li Jun , Wang Lingjie , Pan Ling , Hu Ziao , Yin Ruiqiang , Liu Jia-Fu
Published: July 2024

Introduction

The mental health (MH) of college students has long been a crucial concern for families, educational institutions, and society. Extensive research has demonstrated the influential role of exercise motivation in shaping MH. However, further investigation is warranted to ascertain which types of exercise motivation may have more influence on the MH of college students. The present study examined the direct effects of five distinct types of exercise motivation, namely health motivation (HM), appearance motivation (APM), fun motivation (FM), ability motivation (ABM), and social motivation (SM) on MH. Additionally, the study explored the potential mediating role of physical exercise (PE) in these relationships.

Methods

An cross-sectional study design was employed. A total of 433 Chinese college students participated in the study and completed our questionnaires, which included the Exercise motivation scale (EM scale), the Physical exercise scale (PE scale), and the Mental health scale (MH scale).

Results

The findings revealed a significant and positive relationship between all five categories of exercise motivation and the MH of college students. Specifically, FM was found to have the most pronounced impact on MH, followed by HM, ABM, SM, and APM, in descending order of influence. Furthermore, the impacts of HM, FM, ABM, and SM on MH were found to be partially mediated by PE. However, the association between APM and MH was entirely mediated by PE.

Discussion

The present study contributes to enhancing the comprehension of the underlying mechanisms behind different exercise motivations in relation to PE and MH. Additionally, it offers practical implications for developing intervention strategies for improving the MH of college students.
Non-suicidal self-injury in the COVID-19 pandemic: results from cross-sectional surveys among Brazilian adults from 2020 to 2023
Authors: Faro Andre , Lisboa Walter , Silva-Ferraz Brenda F. , Falk Derek
Published: July 2024

The multilevel psychosocial stressors associated with COVID-19 pandemic set the stage to investigate risk factors and groups susceptible for non-suicidal self-injury (NSSI). A national sample of 9,929 Brazilian adults aged 36.1 years on average participated in the study. Cross-sectional data were collected in 2020, 2021, 2022, and 2023. NSSI levels were considered high in the total sample (13.2%) when compared to other studies in this context. The variables with the highest explanatory power in the regression models were age, anxiety, and depression. The main risk factors were being younger, living in the South or Southeast regions of Brazil, having lower educational attainment, and having higher rates of anxiety and depression. Respondents had the highest probability of NSSI in 2022. The sustained higher rates of NSSI in 2023 compared to the beginning of the pandemic underscores the need for continuous monitoring and the development of preventive actions for self-injurious behaviors.
Reaching out to fathers in Afro-Caribbean contexts: a case study review of best practices from the Fatherhood is Sacred program in native communities
Authors: Hudson Suzette , Brotherson Sean E.
Published: July 2024

Historical trauma has played a significant role in the difficulties of fathers to fulfill their coparenting roles in Native American communities. This pattern is also true for men in Afro-Caribbean communities. Fatherhood programs developed by the Native American Fatherhood and Family Association (NAFFA) have shown effectiveness in supporting fathers, enhancing their confidence and coparenting skills, and overcoming trauma in Native communities. This paper seeks to identify the opportunities and best practices for cross-cultural adaptation of the Fatherhood is Sacred program to Afro-Caribbean families and contexts.
Psychosocial treatment options for adolescents and young adults with alcohol use disorder: systematic review and meta-analysis
Authors: Belay Getaneh Mulualem , Mak Yim Wah , Wong Frances Kam Yuet , Lam Katherine Ka Wai , Liu Qi , Yang Funa , Mao Ting , Wu Cynthia Sau Ting , Ho Ka Yan
Published: July 2024

Introduction

Psychosocial intervention is imperative for treating alcohol use disorder (AUD), but there is no comprehensive evidence regarding its effectiveness. Therefore, this study aimed to determine the effectiveness of psychosocial interventions in treating AUD amongadolescents and young adults.

Methods

In this systematic review and meta-analysis, articles were searched from EMBASE, PubMed, Medline, CINAHL, Web of Science, PsycINFO, and Scopus. Also, articles were retrieved from gray literature. The quality of articles has been assessed using the Cochrane risk of bias assessment.

Results

A total of 12 randomized controlled trials were included. Integrated family and CBT, CBT, guided self-change, and ecologically based family therapy had a mild effect in reducing alcohol use frequency. On the other hand, integrated motivational enhancement therapy and CBT (−0.71 [95% CI: −0.97, −0.45]) and common elements treatment approaches (4.5 [95% CI: 6.9, 2.2]) had the highest effect size for reducing alcohol use frequency and amount, respectively. In conclusion, most of the interventions had no significant effect on different drinking outcomes. Nonetheless, the effectiveness of combined interventions surpassed that of the single interventions. The effect of psychosocial interventions on abstinence was inconclusive. Therefore, future studies will explore alternative, newly emerged third-wave therapeutic approaches.

Systematic review registration

PROSPERO, CRD42023435011, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=435011.
Suitability of different in-water algorithms for eutrophic and absorbing waters applied to Sentinel-2 MSI and Sentinel-3 OLCI data
Authors: Ansper-Toomsalu Ave , Uusõue Mirjam , Kangro Kersti , Hieronymi Martin , Alikas Krista
Published: July 2024

Optically complex waters present significant challenges for remote sensing due to high concentrations of optically active substances (OASs) and their inherent optical properties (IOPs), as well as the adjacency effect. OASs and IOPs can be derived from atmospheric correction processors’ in-water algorithms applied to data from Sentinel-2 MultiSpectral Instrument (S2 MSI) and Sentinel-3 Ocean and Land Color Instrument (S3 OLCI). This study compared S3 OLCI Level-2 in-water products for Case-2 waters with alternative in-water algorithms derived from ACOLITE, POLYMER, C2RCC, and A4O. Fifty in-water algorithms were evaluated using an extensive match-up dataset from lakes and coastal areas, focusing particularly on small lakes with high colored dissolved organic matter absorption at 442 nm (up to 48 m-1). The Chl a band ratio introduced by Gons et al. (2022) applied to data processed by ACOLITE performed best for S3 OLCI Chl a retrieval (dispersion = 23%, bias = 10%). Gons et al. (2022) band ratio also showed consistent agreement between S3 OLCI and S2 MSI resampled data (intercept of 6.27 and slope of 0.83, close to the 1:1 line); however, lower Chl a values (<20 mg/m3) were overestimated by S2 MSI. When estimating errors associated with proximity to land, S2 MSI Chl a in-water algorithms had higher errors close to the shore (on average 315%) compared to S3 OLCI (on average 150%). Chl a retrieved with POLYMER had the lowest errors close to the shore for both S2 MSI and S3 OLCI data (on average 70%). Total suspended matter (TSM) retrieval with C2RCC performed well for S2 MSI (dispersion 24% and bias −12%). Total absorption was most accurately derived from C2RCC applied to S3 OLCI L1 data (dispersion < 43% and bias < −39%), and it was better estimated than its individual components: phytoplankton, mineral particles, and colored dissolved organic matter absorption. However, none of the colored dissolved organic matter absorption in-water algorithms performed well (dispersion > 59% and bias < −29%).
Understanding the diversity of Community Supported Agriculture: a transdisciplinary framework with empirical evidence from Germany
Authors: Middendorf Matthias , Rommel Marius
Published: July 2024

Introduction

Community Supported Agriculture (CSA) is an emerging model within alternative food networks (AFNs). It shapes close relationships between food producers and consumers, thereby contributing to food sovereignty and agri-food system transformations. Despite rapid growth from about 10 to over 500 CSAs in just over a decade, the model in Germany still remains niche. We argue that further and faster scaling up requires better understanding of its diversity, yet a comprehensive conceptualization of CSA types is lacking, with insufficient differentiation in research and practice.

Methods

This study employs a transdisciplinary mixed-methods approach (literature, qualitative, and quantitative data) in cooperation with the German CSA Network. By integrating organizational perspectives, we found that CSAs are highly complex and diverse organizations. Therefore, we firstly aimed at identifying characteristics that we summarized in a CSA framework. In a second stage, we used this framework as guiding structure for co-developing a survey with the Network covering 70 participating CSAs.

Results

As the defining characteristic within the CSA framework, community financing (domain A) clarifies the uniqueness of the CSA model, thus enables delimitation from other AFN forms. Then differentiation characteristics (domain B) encompass the diversity of CSA configurations. CSA governance (domain B1), regarding the predominant characteristic of organizational governance, distinguish between Producer-led, Consumer-led, and Integrated (all-in-one) CSA types. Varying characteristics (domain B2) specify CSA configurations and enable additional distinction between CSAs. Based on the developed CSA framework, the survey results verify the applicability of governance types in particular, while confirming a high level of diversity of differentiating characteristics in general.

Discussion

This study can be used to reveal existing generalizations about CSAs, providing a starting point for more nuanced and critical views in research and practice. When seen against the background of AFN and food sovereignty discourses in particular, CSA is an alternative production-distribution model, but not every CSA is governed or structured in alternative ways. CSAs can simultaneously contain both more conventional, traditional elements, as well as more alternative elements. Moreover, the framework provides easy-to-access differentiation criteria for matching members with their most suitable CSAs and vice versa. Overall, this study illustrates that CSA cannot be considered as homogeneous AFN type but be rather marked as a diverse field of its own.
Participatory Guarantee Systems: structure, benefits and reasons for participation – insights from the Italian case study of Campi Aperti
Authors: Winkler Greta , Kaufmann Sonja , Hruschka Nikolaus , Vogl Christian R.
Published: July 2024

Participatory Guarantee Systems (PGS) have emerged from initiatives introduced by farmers and civil society to ensure the organic quality of products by directly involving producers, consumers, and other stakeholders in the guarantee process. While actor participation in PGS provides the foundation for these systems, it also presents challenges, yet little empirical research on this has been undertaken. This study used a framework to analyze four dimensions of participation in PGS: who, how, what kind, and why? The Italian case study of Campi Aperti was qualitatively and quantitatively analyzed by means of: (1) research of internet documents, (2) semi-structured interviews with seven key members and one expert, and (3) an online survey of PGS members (N = 614 members, survey respondents: n = 16 producers and 45 co-producers). Participation took the form of two main activities: management of the guarantee process and organization of farmers’ markets. Discussions are held and decisions made at assemblies and market meetings. The growing number of producers joining the PGS has added to organizational tasks, and hence increased costs. Participants stated that the reasons for joining the Campi Aperti PGS and the benefits of being a member were to gain access to city markets and to send a political message. Building trust between members was an additional benefit cited. Time constraints emerged as the main drawback preventing participation by members, with producers taking on more roles and investing more time in the PGS than co-producers. However, co-producers provided evidence of other ways in which they participated in the PGS, in particular by making purchases and socializing at the markets.
Characterization of a human thyroid microtissue model for testing thyroid disrupting chemicals
Authors: Rogers E. , Breathwaite E. K. , Nguyen-Jones T. , Anderson S. M. , Odanga J. J. , Parks D. T. , Wolf K. K. , Stone T. , Balbuena P. , Chen J. , Presnell S. C. , Weaver J. R. , LeCluyse E. L.
Published: July 2024

Perturbation of thyroid hormone (T4) synthesis is known to cause numerous developmental, metabolic, and cognitive disorders in humans. Due to species differences in sensitivity to chemical exposures, there is a need for human-based in vitro approaches that recapitulate thyroid cellular architecture and T4 production when screening. To address these limitations, primary human thyrocytes, isolated from healthy adult donor tissues and cryopreserved at passage one (p’1) were characterized for cellular composition, 3D follicular architecture, and thyroglobulin (TG)/T4 expression and inhibition by prototype thyroid disrupting chemicals (TDC). Flow analysis of the post-thaw cell suspension showed >80% EpCAM-positive cells with 10%–50% CD90-positive cells. When seeded onto 96-well Matrigel®-coated plates and treated with bovine thyroid stimulating hormone (TSH), thyrocytes formed 3D microtissues during the initial 4–5 days of culture. The microtissues exhibited a stable morphology and size over a 14-day culture period. TG and T4 production were highest in microtissues when the proportion of CD90-positive cells, seeding density and thyroid stimulating hormone concentrations were between 10%–30%, 6K–12K cells per well, and 0.03–1 mIU/mL, respectively. At maximal TG and T4 production levels, average microtissue diameters ranged between 50 and 200 µm. The T4 IC50 values for two prototype TPO inhibitors, 6-propyl-2-thiouracil and methimazole, were ∼0.7 µM and ∼0.5 µM, respectively, in microtissue cultures treated between days 9 and 14. Overall, p’1 cryopreserved primary human thyrocytes in 3D microtissue culture represent a promising new model system to prioritize potential TDC acting directly on the thyroid as part of a weight-of-evidence hazard characterization.
Wind-Load Calculation Program for Rectangular Buildings Based on Wind Tunnel Experimental Data for Preliminary Structural Designs
Authors: Shin Dong-Hyeon , Ha Young-Cheol
Published: July 2024

In this study, we developed a wind load calculation program (WCP) capable of predicting wind loads with relative precision during the preliminary design phase. First, wind tunnel tests were conducted to identify the essential factors necessary for calculating wind loads and the variables influencing these factors. Square building shapes were considered, and the wind force coefficients and power spectral density were measured by combining four ground roughness values, eleven side ratios (D/B), four aspect ratios (H/BD), and wind directions ranging from 0° to 90°. The wind power coefficient and the spectral coefficient were formulated so that the wind load could be calculated according to various conditions. The WCP computations were based on the calculation of the load combination coefficient using the resonant wind load. Finally, the wind loads obtained from the wind tunnel tests were compared with those predicted by the WCP using an actual project model (inner-core (A) and outer-core (B) types). Building A yielded similar WCP and wind tunnel experimental responses when subjected to wind and laminar wind loads. Additionally, Building B yielded a larger error than that of Building A, but similar results were obtained when buildings were subjected to combination and laminar wind loads.
Power Factor Analysis of Grid-Connected Solar Inverter under Different Irradiance Levels throughout the Day
Authors: Adak Suleyman
Published: July 2024

The power factor (PF) plays a crucial role in determining the quality of energy produced by grid-connected photovoltaic (PV) systems. When irradiation levels are high, typically during peak sunlight hours, the PV panels generate more electricity. In this scenario, the PF tends to be higher because the real power output closely matches the apparent power drawn from the grid. Whereas, when irradiation levels are low, such as during cloudy weather or nighttime, the PV panels produce less electricity. In these conditions, the power factor may decrease because the real power output diminishes compared to the apparent power drawn from the grid. This could be due to reduced efficiency or increased reactive power flow. PF decreases linearly at solar irradiance values lower than 220 (W/m2). At the same time, it approaches unity at higher solar irradiance values than 220 (W/m2). In this study, the variation of the power coefficient of the grid-connected PV solar system depending on solar irradiation was modeled and analyzed using MATLAB/Simulink 41016490. The analytical expression of the power factor depending on the change in solar irradiation was found using the curve fitting method.
Exploring the Impact of Positive Psychology-Based Virtual Music Therapy on Mental Health in Stressed College Students during COVID-19: A Pilot Investigation
Authors: Han Jinwoo , Lee Hyejin , Kim Teri , Lee Sangyeol
Published: July 2024

This study explored the effectiveness of a virtual music therapy program, based on positive psychotherapy principles, in college students during the COVID-19 pandemic. Twenty-four undergraduate students with partial PTSD were initially assigned to either an experimental group or a control group, with 11 participants in each group by the study’s end. The experimental group underwent 15 video sessions of the therapy program, completing one session per weekday over 3 weeks. The program involved worksheets targeting goals aligned with positive psychology, such as positive affect, life meaning, personal strengths, gratitude, hope, and happiness. The activities included writing music autobiographies, creating and analyzing song lyrics, and exploring various music pieces. The effectiveness of the intervention was measured using the 21-item Depression Anxiety Stress Scale and the Korean Version of Positive Psychological Capital (K-PPC) before, immediately after, and 3 weeks post-program. The experimental group showed significant improvements in stress (F = 5.759, p < 0.05), anxiety (F = 4.790, p < 0.01), depression (F = 5.740, p < 0.01), self-efficacy (F = 3.723, p < 0.05), resilience (F = 4.739, p < 0.05), and the K-PPC total score (F = 3.740, p < 0.05) compared with the control group. These improvements were maintained at the 3-week follow-up. The findings suggest that positive psychology-based virtual music therapy can significantly enhance the mental health of highly stressed college students, especially during challenging times such as the COVID-19 pandemic.
Thickness Effect of 2195 Al–Li Alloy Friction Stir Weld Fracture Toughness
Authors: Song Kejin , Liang Peichen , Fu Xuesong , Hu Zhenggen , Chen Guoqing , Zhou Wenlong
Published: July 2024

For damage tolerance design in engineering components, the fracture toughness value, KIC, of the material is essential. However, obtaining specimens of sufficient thickness from stir friction welded plates is challenging, and often, the experimental test values do not meet the necessary criteria, preventing the experimental fracture toughness, Kq, from being recognized as plane strain fracture toughness KIC. The fracture toughness Kq of 2195 Al–Li alloy welding seams with different thicknesses was measured on the forward and backward sides. Microstructure characterization was conducted by scanning electron microscope (SEM). The results indicated minimal significant differences in grain size between the advancing and retreating sides of the weld nugget zone. In specimens of the same thickness, fracture toughness measurements along the normal direction of the joint cross-section showed a high similarity between the advancing and retreating sides of the weld nugget zone. Utilizing the quantitative relationships between fracture toughness and sample thickness derived from both the fracture K and G criteria, it is possible to predict the fracture toughness of thick plates using thin plates. This study employs these relationships to calculate the fracture toughness KIC of 2195 aluminum–lithium alloy friction stir welds. The KIC values obtained are 41.65 MPa·m1/2 from the fracture K criterion and 43.54 MPa·m1/2 from the fracture G criterion.
The Impact of Vessel/Ship Noise on the Productivity and Well-being of Maritime Crew: A Holistic Examination
Authors: Ologe Solomon Ochuko , Anaidhuno Ufuoma Peter , Oshundairo Idowu Mushafau
Published: July 2024

This comprehensive survey examines the impact of vessel/ship noise on the productivity and well-being of 500 maritime crew members. The study explores the multifaceted repercussions of regular exposure to ship-related noise on both the operational efficiency and overall health of seafarers.
Through an extensive examination of existing literature and first-hand assessments, the research delves into the physiological and psychological effects of vessel noise on crew members. Statistical Package for the Social Sciences (SPSS) and descriptive geometry were utilized to analyse the
field response data. Additionally, it evaluates the potential implications for maritime safety and productivity. Investigated noise levels range from 60 to 110 dB, observed productivity ranges from 40 to 90%, and well-being ranges from 60 to 95%. The findings from this survey offer valuable
insights to the maritime industry, illuminating the complex relationship between ship noise, crew well-being, and operational performance. Keywords: Maritime Noise Impact, Crew Well-being, Holistic Examination, Productivity Challenges and Vessel Sound Effects.
Understanding the Fourier Transform
Authors: Hiatt John
Published: July 2024

This presentation will focus on understanding the assumptions of the Fourier transform and how these assumptions affect the frequency domain data.  We will discuss the inputs the software requires to process the Fourier transform and the outputs created from the transform. 
Also, we highlight why the frequency domain output of different software packages might not match.
Acoustic Characterization of the NASA Langley 14- by 22-Foot Subsonic Tunnel using a Phased Array
Authors: Houston Mary , Stutz Colin Matthew , Zawodny Nik , Pascioni Kyle A.
Published: July 2024

A characterization test was conducted in the NASA Langley Research Center 14- by 22-Foot SubsonicTunnel to assess recent acoustic modifications in the facility. Test section reflectivity, backgroundnoise and shear layer effects were evaluated by taking measurements of known noise sources.Both
conventional speakers and a high-pressure air source were employed as noise generationmechanisms. These were mounted to a pole or fairing at a consistent location in the test section.The source waveforms were used to represent the expected frequency content of scaled Urban AirMobility vehicles.
Acoustic measurements were taken using two unique microphone arrays placed outside the core flow, one of which was a 54-element streamwise-traversing phased array. The other was an 11-element linear tower array. The applicability of phased array acoustic beamforming techniques to mitigate
shear layer effects and reject background noise is presented. Additionally, beamforming results are compared to results from single-microphone processing techniques. Flow speeds investigated ranged from Mach 0.00 (static) to Mach 0.12. The tunnel has been partially acoustically treated but
still exhibits flow noise, reducing the signal-to-noise ratio of the source under investigation. Conventional beamforming was able to capture high frequency content passing through the shear layer better than single microphone measurements. CLEAN deconvolution improves source mapping at low
frequencies.
It's only one more data center! When scope creep becomes sound emissions creep
Authors: Conaway Michael , Baldassano John
Published: July 2024

A single data center project was originally proposed next to a residential area on a portion of a defunct train yard slated for redevelopment. Sound emissions from this data center's exterior noise sources were evaluated via acoustical modelling; results were compared with regulatory
limits, and noise control recommendations were issued to the client. A second data center, operated by the same client, was then proposed adjacent to the first data center project. After this second data center was analyzed and noise control recommendations were issued to the client, a third
data center was proposed adjacent to the second data center. This presentation will discuss this case study and the scope and sound emissions creep of these three data center projects.
Acoustic characterization of the NASA Langley 14- by 22-Foot Subsonic Tunnel using single-microphone analysis techniques
Authors: Stutz Colin Matthew , Houston Mary , Zawodny Nik , Pascioni Kyle A.
Published: July 2024

An experimental campaign was carried out to assess recent acoustic modifications to the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel. This effort was undertaken in preparation for future rotorcraft, Advanced Air Mobility, and airframe noise acoustic tests. The tunnel
is a closed circuit and typically operates in an open-jet configuration for acoustic studies. A vertical linear array of microphones and a phased array were placed on traverses outside of the core flow. Pole-mounted acoustic sources with known waveforms were used to identify sources of reflection
under static conditions. A similar process was replicated with more compact sources in an aerodynamic fairing for flow speeds up to Mach 0.16. This allowed for acoustic characterizations of the test section core flow and bounding shear layer. Periodic averaging was investigated as a method
for isolating acoustic sources and was shown to be capable of isolating periodic acoustic signals even for poor signal-to-noise ratio conditions. Benefits and limitations of single-microphone processing methods are identified. A companion paper utilizes a phased array in an effort to address
the identified limitations to more traditional single-microphone data collection.
Test method for evaluating the NIOSH Noise Mapper application in a hemi-anechoic chamber
Authors: Yan Lincan , Elmashae Yousef , Hrica Jonathan , Yantek David S.
Published: July 2024

The Noise Mapper Application developed by the National Institute for Occupational Safety and Health (NIOSH) can be used to identify areas in the workplace where workers may be exposed to hazardous noise. The app was created to empower workers to measure sound levels in their workplace,
make informed decisions about noise exposure, and prevent occupational hearing loss. To evaluate the maps generated by the app, a single sound source or multiple sources were used to generate steady state sound fields within the NIOSH hemi-anechoic chamber (HAC). A sound level meter (Larson
Davis, Model 831C) was used to measure A-weighed equivalent continuous sound levels on a grid with a spacing of 1.5 m (5 ft). The NIOSH Noise Mapper app was then used to generate sound level contour plots with a grid spacing of 3.0 m (10 ft). The accuracy of the map was evaluated by comparing
the predicted sound levels with the measured sound levels. The results show the app can estimate the sound levels to within ±1.2 dB(A) of the measured values. The test method used to evaluate the NIOSH Noise Mapper app and the results of the comparison will be discussed in this paper.
Creating noise contour maps utilizing the NIOSH Noise Mapper App (A pilot study)
Authors: Elmashae Yousef , Zechmann Edward
Published: July 2024

High noise levels can lead to physical and psychological stress, reduced productivity, and permanent hearing loss in workers. Traditional noise monitoring techniques indicate that mine workers, for example, consistently have a higher level of noise exposure when compared to workers
in other heavy industries. It is critical to conduct risk assessments, identify noise sources, and control them to prevent occupational noise-induced hearing loss (ONIHL). The National Institute for Occupational Safety and Health (NIOSH) has recently developed the smartphone-based NIOSH Noise
Mapper Application, which generates a noise contour map to enable individuals, workers, and hearing conservation professionals to apply the hierarchy of controls for optimized prioritization and focused targeting of the most effective hearing conservation interventions. Preliminary testing
of the Noise Mapper app has been carried out in a hemi-anechoic chamber at the NIOSH Mining Laboratory in Pittsburgh. The results demonstrate that the Noise Mapper app can quickly and cost-effectively generate adequate noise contour maps to identify noise hazards and relevant noise-generating
machinery to prioritize and target the most effective interventions. However, additional testing is needed to evaluate the Noise Mapper app's performance in real-world environments and its ability to measure multiple sound sources. This new tool supplements, but does not, replace traditional
methods of creating noise contour maps.
Sound isolation and speech privacy observations of modular wall construction in healthcare environments
Authors: Davenny Benjamin
Published: July 2024

A recent trend in healthcare spaces is emerging where exam room walls are stopping at or just above the ceiling. There are a number of reasons for doing this, including cost, large floor-to-floor heights, desire for prefabricated constructions, and the need for plenum flexibility for
building services. The speech privacy at these locations is critically dependent on the noise reduction of the wall, door, and ceiling constructions as well as the sound masking system. Sound masking systems, long delivered directly from manufacturers or their representatives, are now being
repackaged and sold by furniture vendors. Measurements and observations from the field will be presented. Locations where sound masking is not recommended and where upgraded construction is required will be discussed.
Pickleball sounds: impact induced vibration and radiated sound
Authors: Moore James A.
Published: July 2024

The rapid growth in popularity of pickleball and the ever-increasing number of pickleball courts has resulted in growing concerns about the effect of pickleball sounds on nearby neighbors. The vibration of the ball and paddle that is generated at impact, and which is the source of the
radiated sound, was measured for different paddles as a function of frequency using an impact hammer instrumented with a force gage. Average vibration velocities over the paddle surface were generated that scale the radiated sound. Animations of paddle vibration were also generated. A paddles
vibration level depends on its internal mechanical damping which was also measured. A performance metric is proposed where the paddles' sound levels are compared at the same "power" in terms of the change in momentum (velocity) of the pickleball on impact. Outdoor directivity measurements
of the sound for a paddle were "dipole-like" in character with lower levels, by 10 dB or more, in the plane of the paddle compared to levels perpendicular to its face. The orientation of the courts may be important if the sound levels during play are quieter in the general direction
along the nets.
Measured outdoor-indoor noise reduction through various open window sizes
Authors: Zybura Jack
Published: July 2024

Quantifying the effect of window openings on composite noise reduction of building façades is useful for evaluation with respect to noise regulations that prescribe indoor sound level limits with open window conditions. There are historical documents that indicate overall sound
level reductions of open and closed windows, but there is little data available in octave band or one-third octave band resolution, or on the effect of the opening size. A series of Outdoor-Indoor Noise Reduction measurements were performed on a residential façade with closed-window
and various open-window configurations. The test room was normally furnished with an approximate room volume of 64 m3. The open window areas ranged from approximately 1 to 13% of the total façade area. In addition to presenting one-third octave band results, the overall noise reduction
ratings were computed using the reference sound spectrum from ASTM E1332. The overall noise reduction results show a trend of higher reduction with smaller open window area as expected. The results of the measurements also show that the slope of the trend varies with frequency.
Comparison of train noise and vibration measurements with U.S. Department of Transportation model predictions
Authors: Towers David Allan
Published: July 2024

Wayside noise and ground-borne vibration measurements of freight and light rail train operations were carried out in Denver, CO in support of the Burnham Yard Transportation Planning Study being pursued by the Colorado Department of Transportation (CDOT). This study was intended to
evaluate various track layout alternatives for the Consolidated Main Line (CML) freight railroad alignment and enhancement of Regional Transportation District (RTD) light rail operations while maintaining options for Front Range Passenger Rail (FRPR) within Burnham Yard and the surrounding
areas. The objective of the measurements was to compare measured train noise and vibration levels with predictions using models sanctioned by the U.S. Department of Transportation (USDOT) in order to validate the use of these models to assess the noise and vibration impacts of the project
alternatives. The models included the Federal Railroad Administration (FRA) Chicago Rail Efficiency And Transportation Efficiency (CREATE) freight noise model, the FRA Horn Noise Model, and the models included in the Federal Transit Administration (FTA) Transit Noise and Vibration Impact Assessment
Manual. Based on a comparison of measured and modeled results, it was concluded that the USDOT models could be used to assess noise and vibration from train operations in the Burnham Yard Study Area.
Aviation noise in the United States: The current state of FAA research on community response
Authors: Scholten Adam , Czech Joseph , Scata Jr. Donald Steven , Grandi Fabio
Published: July 2024

While today's civilian aircraft fleet is quieter than at any time in the history of jet-powered flight, the Federal Aviation Administration (FAA) continues to receive complaints about aircraft noise affecting communities across the United States. Additionally, the FAA's Neighborhood
Environmental Survey (NES) has shown that community response to aviation noise in the United States has changed and the dose-response relationship between noise and annoyance such as the one represented by the Shultz Curve is no longer representative of communities' lived experiences. This
paper will examine the current aviation noise environment in the United States and how the nature of aviation noise and the characteristics of communities that raise significant noise concerns in the United States have changed since the start of widespread use of commercial jet-powered aircraft
in the 1960s. This paper will also explore the changing nature of community response to aviation noise based on the FAA's latest research findings on aviation noise and annoyance as detailed in follow-on analyses to the NES.
An Acoustical Survey of a Catholic Chapel
Authors: Plutt Matthew Boyce
Published: July 2024

The modern-day celebration of the Roman Catholic Mass places an increased emphasis on the speech, music, and participation of the congregation in these ministries. Thus, there is an increasing emphasis on ensuring churches provide acceptable experiences for speech and music. This paper
presents the results of an empirical study of a Roman Catholic chapel. The acoustic metrics were determined from impulse response data gathered via microphones recording balloon pops. Sound pressure level measurements were gathered with a sound pressure meter recording a boombox noise source.
The balloon pops and boombox noise source were placed in various locations indicative of sources during the celebration of the Mass. Findings include that the RT30 measurements of the chapel were consistent with the EDT values suggesting that early reflections should not provide a significant
impact on the perceived reverberation of the chapel. Based on the results, we conclude that the chapel does not have any significant deficiencies in its ability to transmit speech and music. This provides a basis for the chapel administration to invest in a professional assessment as they
begin a project to install a new organ and choir loft.
Selection of induction motor stator and rotor slot number combination for optimal NVH
Authors: Ba Jing , Ambarisha Vijaya Kumar , Sun Zhaohui , Ong Raymond
Published: July 2024

With the rise of vehicle electrification, considerable research has been directed towards reducing motor noise, predominantly focusing on Permanent Magnet Synchronous Motors (PMSM). Despite the increasing popularity of the induction motor, driven by its reliability, cost-effectiveness,
and lower environmental impact, discussions surrounding the Noise, Vibration, and Harshness (NVH) aspects of induction motors remain limited. This paper addresses the NVH implications associated with stator and rotor slot combinations in conventional squirrel-cage induction motors. Through
a design parametric study that examines the impact of varying the number of rotor bars through analytical simulation, the findings not only identify the optimal slot combination for minimizing motor noise but also demonstrate the critical importance of selecting the proper slot configuration,
as NVH performance can exhibit significant variations. A physical test was conducted to validate the analytical simulations. This research contributes valuable insights into the induction motor design, especially at the early design stage, emphasizing the necessity of considerations in achieving
enhanced NVH performance.
Realizing a 21st Century Noise Policy
Authors: Yaplee Darlene E. , Christiansen Cindy L. , Fremont Marie-Jo
Published: July 2024

Aviation noise impacts affect the health and quality of life of communities nationwide. The FAA's noise policy, last updated in the 1970s, uses a single decision-making metric (DNL), to determine the significance of noise impacts caused by aircraft operations. The Neighborhood Environmental
Survey (NES), released in 2021, shows that many more people are impacted by aircraft noise and at levels far below 65 dB DNL than previously thought. The current noise policy does not reflect the 21st century airspace environment, including the consequences of NextGen and the tremendous growth
in air traffic. An important improvement to realize an up-to-date noise policy is to reflect the lived experience of impacted communities more accurately. This paper will cover how communities experience aircraft noise in two separate noise exposure environments both near and away from airports,
which practices are issues and most concerning to communities, what metrics more accurately evaluate impacts, and how a more community-centric approach provides a better representation of the aviation noise experienced by people, which is fundamental to operating a National Airspace System
that works for all.
Assessment and Analysis of Reverberation Time in Hyder-Burks Arena at Tennessee Technological University
Authors: Savage Alex , Wall Colin Roland , Oyekola Peter Oluwatosin , Rao Mohan
Published: July 2024

This study addresses the issue of long reverberation times in large-scale arenas, specifically the HyderBurks Arena (HBA) at Tennessee Technological University. HBA primarily hosts cattle shows and agricultural events. The current multi-speaker sound system in the facility ensures audibility,
but the long reverberation time accumulates noise that impairs communication and causes dissatisfaction. The objectives of this work conducted as a student project in an undergraduate noise control class include measuring the reverberation time, analyzing the data, researching noise reduction
methods, and proposing feasible plans that consider cost, achievability, and ease of implementation. The current reverberation time measured in the arena is approximately 2.313 seconds, posing challenges for speechapplications. The aim was to reduce this to a range of 1.32 to 1.02 seconds.
The study employed a Larson Davis Sound Advisor 831C sound level meter to measure the reverberation time at various points in the arena. Despite low-frequency analysis challenges, critical frequencies affecting speech intelligibility were identified. The study also highlights potential issues
with the arena’s sound system and the need for a synchronized, centralized speaker system. The assessment revealed that areas near the concrete walls without sound absorption have the maximum T60, indicating the need for treatment. Recommendations include ceiling treatment to reduce
the reverberation time and enhance speech intelligibility. The proposed plan, considering cost-effectiveness and financial feasibility, aims to improve the atmosphere and experience for HBA users.