bluuebunny/crossref_metadata_2025 huggingface dataset:
Digital Determination and Recording of Edentulous Maxillomandibular Relationship Using a Jaw Movement Tracking System
Authors: Li Weiwei , Chen Hu , Wang Yong , Xie Qiufei , Sun Yuchun
Published: May 2022

Purpose

To establish a direct digital method for determining and recording edentulous maxillomandibular relationship using a custom‐made jaw movement tracking system and evaluate its accuracy.

Materials and methods

A novel jaw tracking system was used to record the trajectory of habitual opening‐closing jaw movement, and mandibular rest position (MRP) in 10 edentulous patients. 3D surface scanning was performed on the conventional maxillomandibular impressions and facial structures of patients in MRP. The multisource data were registered using a custom‐made recording tool. A plane parallel to the ala‐tragus and horizontal lines was constructed 2 mm above the MRP, and its vertical position was used to determine the vertical relationship. The intersections of the trajectory passing through the plane were located, and their density distributions were analyzed. The coordinates of highest density, which presented the highest repeatability of jaw movement, were used to construct the digital maxillomandibular relationship (test group). The maxillomandibular relationship of the new complete dentures with artificial teeth in the intercuspal position was defined as the control group. The displacements of the anterior reference point and 3D deviations of the entire mandibular arch were measured and compared between the test and control groups using a Wilcoxon signed‐ranks test and a one‐sample t‐test, respectively.

Results

With reference to the centric relationship position, the maximum displacements of the anterior reference points were in the horizontal anteroposterior direction for both groups, and there were no significant differences. Compared to the control group, the 3D deviations of the entire mandibular arch in the test group were significant (95% confidence interval: 0.76 mm to 1.35 mm, p < 0.001).

Conclusions

By analyzing the individual trajectory features obtained by the in‐house developed jaw tracking system, a digital method for determining and recording edentulous maxillomandibular relationships was established; however, the accuracy needs to be further improved.
Phenotypic and genotypic approach to characterize a Trueperella pecoris strain isolated from necrotic vestibulitis of a camel (Camelus dromedarius)
Authors: Ahmed M.F.E. , Alssahen M. , Lämmler C. , Hoffmann C. , Prenger-Berninghoff E. , Ewers C. , Plötz M. , Abdulmawjood A.
Published: May 2022

The present study was designed to characterize phenotypically and genotypically a Trueperella (T.) pecoris strain isolated from necrotic vestibulitis of a 10-year-old camel (Camelus dromedarius). The species identity of T. pecoris 203/7 investigated in the present study could be confirmed by phenotypic properties and by phylogenetic analyses based on partial sequencing of the 16S ribosomal RNA (rRNA) gene, the 16S-23S rDNA intergenic spacer region, the glyceraldehyde 3-phosphate dehydrogenase encoding gene gap, elongation factor Tu encoding gene tuf and the target gene rpoB encoding the β-subunit of bacterial RNA polymerase. T. pecoris strain 203/7 was grouped within the genus Trueperella in the family Arcanobacteriaceae. The 16S rRNA gene analysis showed a sequence identity of 99·9% to reference strain T. pecoris DSM 111392T. The present isolate was clearly identified as T. pecoris, the most recently described species of the genus Trueperella. Strain T. pecoris 203/7 was isolated in moderate numbers from necrotic vestibulitis of the camel and could be of some importance for the infectious process. However, the investigated strain represents the first isolation of T. pecoris from a camel.
Anxiety and Reading Comprehension of Chinese Children with and without Reading Disabilities: The Role of Processing Speed
Authors: Wang Li‐Chih , Chen Ji‐Kang , Tsai Huang‐Ju
Published: May 2022

The present study examined the mediating effect of processing speed on the relationship between state anxiety and reading comprehension in Chinese children with and without reading disabilities (RD). A total of 53 Chinese children with RD and 66 typically developing children were administered cognitive and noncognitive measures. We found that the two groups had distinct patterns of state anxiety and processing speed. A significant indirect effect of state anxiety on reading comprehension through processing speed was found only in children with RD. Our findings contribute to filling a research gap and provide evidence to front‐line practitioners for adapting the teaching and measures for Chinese children with RD.
Liver transplantation in patients with liver failure: Twenty years of experience from China
Authors: Ling Sunbin , Jiang Guangjiang , Que Qingyang , Xu Shengjun , Chen Junli , Xu Xiao
Published: May 2022

Liver transplantation (LT) is the only effective method of treating end‐stage liver disease, such as various types of liver failure. China has the largest number of patients with hepatitis B virus‐related disease, which is also the main cause of liver failure. From the first LT performed in 1977, and especially over the past two decades, LT has experienced rapid development as a result of continuous research and innovation in China. China performs the second‐highest number of LTs every year worldwide, and the quality of LT continues to improve. Starting January 1, 2015, all donor's livers have been from deceased donors and familial donors. Thus, China entered into a new era of LT. However, LT is still a challenging procedure in China. In this review, we introduced the brief history of LT in China, the epidemiology, aetiology and clinical outcomes of LT for liver failure in China and summarized the experience of LT from Chinese LT surgeons and scholars. The future perspectives of LT were also discussed, and it is expected that China's LT research could be further integrated elsewhere in the world.
Interaction between MHC diversity and constitution, gut microbiota and Astrovirus infections in a neotropical bat
Authors: Fleischer Ramona , Schmid Dominik W. , Wasimuddin  , Brändel Stefan D. , Rasche Andrea , Corman Victor M. , Drosten Christian , Tschapka Marco , Sommer Simone
Published: May 2022

Astroviruses (AstVs) infect numerous mammalian species including reservoirs such as bats. Peptides encoded by the genes of the highly polymorphic Major Histocompatibility Complex (MHC) form the first line of host defence against pathogens. Aside from direct involvement in mounting adaptive immune responses, MHC class II genes are hypothesized to regulate gut commensal diversity and shape the production of immune‐modulatory substances by microbes, indirectly affecting host susceptibility. Despite initial empirical evidence for the link between host MHC and the microbiota, associations among these factors remain largely unknown. To fill this gap, we examined MHC allelic diversity and constitution, the gut bacterial community and abundance pattern of a wild population of a neotropical bat (Artibeus jamaicensis) challenged by AstV infections. First, we show an age‐dependent relationship between the host MHC class II diversity and constitution and the gut microbiota in AstV‐uninfected bats. Crucially, these associations changed in AstV‐infected bats. Additionally, we identify changes in the abundance of specific bacterial taxa linked to the presence of certain MHC supertypes and AstV infection. We suggest changes in the microbiota to be either a result of AstV infection or the MHC‐mediated modulation of microbial communities. The latter could subsequently affect microbe‐mediated immunity and resistance against AstV infection. Our results emphasize that the reciprocal nature of host immune genetics, gut microbial diversity and pathogen infection require attention, which are particularly important given their repercussions for disease susceptibility and severity in wild animal populations with a history of zoonotic spillover and frequent human contact.
A targeted approach to investigating immune genes of an iconic Australian marsupial
Authors: Silver Luke W. , Cheng Yuanyuan , Quigley Bonnie L. , Robbins Amy , Timms Peter , Hogg Carolyn J. , Belov Katherine
Published: May 2022

Disease is a contributing factor to the decline of wildlife populations across the globe. Koalas, iconic yet declining Australian marsupials, are predominantly impacted by two pathogens, Chlamydia and koala retrovirus. Chlamydia is an obligate intracellular bacterium and one of the most widespread sexually transmitted infections in humans worldwide. In koalas, Chlamydia infections can present as asymptomatic or can cause a range of ocular and urogenital disease signs, such as conjunctivitis, cystitis and infertility. In this study, we looked at differences in response to Chlamydia in two northern populations of koalas using a targeted gene sequencing of 1209 immune genes in addition to genome‐wide reduced representation data. We identified two MHC Class I genes associated with Chlamydia disease progression as well as 25 single nucleotide polymorphisms across 17 genes that were associated with resolution of Chlamydia infection. These genes are involved in the innate immune response (TLR5) and defence (TLR5, IFNγ, SERPINE1, STAT2 and STX4). This study deepens our understanding of the role that genetics plays in disease progression in koalas and leads into future work that will use whole genome resequencing of a larger sample set to investigate in greater detail regions identified in this study. Elucidation of the role of host genetics in disease progression and resolution in koalas will directly contribute to better design of Chlamydia vaccines and management of koala populations which have recently been listed as “endangered.”
Riverscape genomics of cichlid fishes in the lower Congo: Uncovering mechanisms of diversification in an extreme hydrological regime
Authors: Kurata Naoko P. , Hickerson Michael J. , Hoffberg Sandra L. , Gardiner Ned , Stiassny Melanie L. J. , Alter S. Elizabeth
Published: May 2022

Freshwater fishes are notably diverse, given that freshwater habitat represents a tiny fraction of the earth's surface, but the mechanisms generating this diversity remain poorly understood. Rivers provide excellent models to understand how freshwater diversity is generated and maintained across heterogeneous habitats. In particular, the lower Congo River (LCR) consists of a dynamic hydroscape exhibiting extraordinary aquatic biodiversity, endemicity, morphological and ecological specialization. Previous studies have suggested that the numerous high‐energy rapids throughout the LCR form physical barriers to gene flow, thus facilitating diversification and speciation, generating ichthyofaunal diversity. However, this hypothesis has not been fully explored using genome‐wide SNPs for fish species distributed across the LCR. Here, we examined four lamprologine cichlids endemic to the LCR that are distributed along the river without range overlap. Using genome‐wide SNP data, we tested the hypotheses that high‐energy rapids serve as physical barriers to gene flow that generate genetic divergence at interspecific and intraspecific levels, and that gene flow occurs primarily in a downstream direction. Our results are consistent with the prediction that powerful rapids sometimes act as a barrier to gene flow but also suggest that, at certain temporal and spatial scales, they may provide multidirectional dispersal opportunities for riverine rheophilic cichlid fishes. These results highlight the complexity of diversification processes in rivers and the importance of assessing such processes across different riverscapes.
The language of pluralism from the history of the theory of price determination: Natural price, equilibrium price and administered price
Authors: Bloch Harry
Published: May 2022

This paper seeks to identify terminology to aid in distinguishing the approaches to the theory of price determination as presented in classical political economy, neoclassical economics and post‐Keynesian economics. Through a review of the respective literature, a dominant usage is identified for the theoretical price concept in each theory. Natural price is identified with classical theory, equilibrium price with neoclassical theory and administered price with post‐Keynesian theory. Use of the differentiated terminology is advocated for improving clarity in pluralist discourse on the theory of price determination and the role of prices in modern market economies with their inherent complexity.
A stochastic programming approach to enhance the resilience of infrastructure under weather‐related risk
Authors: Zhang Ning , Alipour Alice
Published: May 2022

The presented methodology results in an optimal portfolio of resilience‐oriented resource allocation under weather‐related risks. The pre‐event mitigations improve the capacity of the transportation system to absorb shocks from future natural hazards, contributing to risk reduction. The post‐event recovery planning results in enhancing the system's ability to bounce back rapidly, promoting network resilience. Considering the complex nature of the problem due to uncertainty of hazards, and the impact of the pre‐event decisions on post‐event planning, this study formulates a nonlinear two‐stage stochastic programming (NTSSP) model, with the objective of minimizing the direct construction investment and indirect costs in both pre‐event mitigation and post‐event recovery stages. In the model, the first stage prioritizes a bridge group that will be retrofitted or repaired to improve the system's robustness and redundancy. The second stage elaborates the uncertain occurrence of a type of natural hazard with any potential intensity at any possible network location. The damaged state of the network is dependent on decisions made on first‐stage mitigation efforts. While there has been research addressing the optimization of pre‐event or post‐event efforts, the number of studies addressing two stages in the same framework is limited. Even such studies are limited in their application due to the consideration of small networks with a limited number of assets. The NTSSP model addresses this gap and builds a large‐scale data‐driven simulation environment. To effectively solve the NTSSP model, a hybrid heuristic method of evolution strategy with high‐performance parallel computing is applied, through which the evolutionary process is accelerated, and the computing time is reduced as a result. The NTSSP model is implemented in a test‐bed transportation network in Iowa under flood hazards. The results show that the NTSSP model balances the economy and efficiency on risk mitigation within the budgetary investment while constantly providing a resilient system during the full two‐stage course.
Alexia and agraphia in Japanese
Authors: Suzuki Kyoko
Published: May 2022

Dissociated performance in the reading/writing of kanji (morphogram) and kana (phonogram) in alexia and agraphia in Japanese has attracted attention because kanji and kana differently convey semantics, orthography, and phonology. Although the dissociation between kanji and kana is relative, but not absolute, detailed case studies, in addition to recent neuroimaging and neurophysiological studies, have revealed the partially separable mechanisms of the kanji and kana writing systems. Kanji words are processed mainly, not exclusively, via the orthographic–semantic route, and kana words are processed via both orthographic–semantic and phonological routes. Pure alexia with lesions in the left medial occipital lobe and splenium shows alexia for both kanji and kana, but at the chronic stage, alexia for either kanji or kana may remain depending on the compensatory mechanism. The left occipitotemporal area is important for reading/writing. The slightly different location and extent of lesions are associated with distinct symptoms: kanji alexia with the lesion in the mid‐fusiform gyrus (visual word form area; VWFA), kana alexia with lesions posterior to VWFA, and kanji alexia with kanji agraphia with lesions lateral to VWFA. The left angular gyrus has traditionally been considered important for writing. However, it is unclear whether the crucial site is the angular gyrus or the cortical and subcortical regions adjacent to it. In neurodegenerative diseases, reading/writing abilities are differentially impaired depending on the specific distribution of neuronal degeneration in each disease. Examining the reading/writing abilities of kanji and kana can facilitate understanding of the writing system and related disorders.
PEAPOD repressors modulate and coordinate developmental responses to light intensity in Arabidopsis
Authors: White Derek W. R.
Published: May 2022

Higher plants adapt to different light intensities by altering hypocotyl elongation, stomatal density, seed size, and flowering time. Despite the importance of this developmental plasticity, knowledge of the underlying genetic and molecular mechanisms modulating and coordinating responses to light intensity remains incomplete. Here, I report that in Arabidopsis the PEAPOD (PPD) repressors PPD1 and PPD2 prevent exaggerated responses to light intensity.

Genetic and transcriptome analyses, of a ppd deletion mutant and a PPD1 overexpression genotype, were used to identify how PPD repressors modulate the light signalling network.

A ppd1/ppd2 deletion mutant has elongated hypocotyls, elevated stomatal density, enlarged seed, and delayed flowering, whereas overexpression of PPD1 results in the reverse. Transcription of both PPD1 and PPD2, upregulated in low light and downregulated in higher light, is activated by PHYTOCHROME INTERACTING FACTOR 4. I found PPDs modulate light signalling by negative regulation of SUPPRESSOR OF phyA‐105 (SPA1) transcription. Whereas PPDs coordinate many of the responses to light intensity – hypocotyl elongation, flowering time, and stomatal density – by repression/de‐repression of SPA1, PPD regulation of seed size occurs independent of SPA1.

In conclusion PPD repressors modulate and coordinate developmental responses to light intensity by altering light signal transduction.
OSCA1 is an osmotic specific sensor: a method to distinguish Ca2+‐mediated osmotic and ionic perception
Authors: Pei Songyu , Liu Yuantao , Li Wenke , Krichilsky Bryan , Dai Shiwen , Wang Yan , Wang Xi , Johnson Douglas M. , Crawford Bridget M. , Swift Gary B. , Vo‐Dinh Tuan , Pei Zhen‐Ming , Yuan Fang
Published: May 2022

Genetic mutants defective in stimulus‐induced Ca2+ increases have been gradually isolated, allowing the identification of cell‐surface sensors/receptors, such as the osmosensor OSCA1. However, determining the Ca2+‐signaling specificity to various stimuli in these mutants remains a challenge. For instance, less is known about the exact selectivity between osmotic and ionic stresses in the osca1 mutant.

Here, we have developed a method to distinguish the osmotic and ionic effects by analyzing Ca2+ increases, and demonstrated that osca1 is impaired primarily in Ca2+ increases induced by the osmotic but not ionic stress.

We recorded Ca2+ increases induced by sorbitol (osmotic effect, OE) and NaCl/CaCl2 (OE + ionic effect, IE) in Arabidopsis wild‐type and osca1 seedlings. We assumed the NaCl/CaCl2 total effect (TE) = OE + IE, then developed procedures for Ca2+ imaging, image analysis and mathematic fitting/modeling, and found osca1 defects mainly in OE.

The osmotic specificity of osca1 suggests that osmotic and ionic perceptions are independent. The precise estimation of these two stress effects is applicable not only to new Ca2+‐signaling mutants with distinct stimulus specificity but also the complex Ca2+ signaling crosstalk among multiple concurrent stresses that occur naturally, and will enable us to specifically fine tune multiple signal pathways to improve crop yields.
Robust crisis communication in turbulent times: Conceptualization and empirical evidence from the United States
Authors: Zhong Wei , Hu Qian , Kapucu Naim
Published: May 2022

Drawing on recent research on robust governance, we conceptualize robust crisis communication as a dynamic process centered on evolving public communication demands. We propose a three‐dimensional measurement for empirically examining the robustness of government crisis communication in the context of the COVID‐19 pandemic. We collected 43,642 Twitter messages posted by 50 state governors in the United States from January 1 to June 30, 2020. We applied machine learning algorithms to code the voluminous Twitter data based on messaging topics, sentiments, and interactions. This study found an overall low level of robustness in the governors' crisis communication. Governors most frequently posted reputation management tweets, followed by tweets about the government's handling of the pandemic. This research presents empirical evidence for the heavy influence of politics on governors' crisis communication strategies and highlights the need to understand and build robust crisis communication.

摘要

本文借鉴稳健性治理的最新相关研究，提出稳健性危机沟通的概念，将其界定为聚焦于满足危机中持续变化的公众沟通需求的动态沟通过程与模式。基于此概念，本文以新型冠状病毒肺炎疫情中的危机沟通为例，构建三维测量方法，用以检验政府危机沟通在内容主题、情感表达和对话互动三方面的稳健程度。本文收集美国50个州长在2020年1月1日至2020年6月30日期间发布的43,642条推特信息，并应用机器学习对所有信息的主题、情感和互动特征进行编码分析。本文发现美国州长危机沟通的稳健性程度总体偏低。美国州长最经常发布与声誉管理相关的推文，其次是政府的疫情防控措施。文章进一步阐释与例证政治因素对州长危机沟通策略的深刻影响，并强调政府部门理解与践行稳健性风险沟通的必要性与重要性。
Milroy disease with predominant preputial involvement
Authors: Pérez‐Bertólez Sonia , Alonso Verónica
Published: May 2022

Milroy disease is a form of congenital primary lymphedema that usually affects the lower limbs. Predominant genital lymphedema in Milroy disease is uncommon and disabling. When conservative management is ineffective, surgical treatment becomes necessary. Here, we present a rare case of congenital primary penile lymphedema in a 4‐year‐old child.
Capturing Dynamic Performance in a Cognitive Model: Estimating ACT‐R Memory Parameters With the Linear Ballistic Accumulator
Authors: van der Velde Maarten , Sense Florian , Borst Jelmer P. , van Maanen Leendert , van Rijn Hedderik
Published: May 2022

The parameters governing our behavior are in constant flux. Accurately capturing these dynamics in cognitive models poses a challenge to modelers. Here, we demonstrate a mapping of ACT‐R's declarative memory onto the linear ballistic accumulator (LBA), a mathematical model describing a competition between evidence accumulation processes. We show that this mapping provides a method for inferring individual ACT‐R parameters without requiring the modeler to build and fit an entire ACT‐R model. Existing parameter estimation methods for the LBA can be used, instead of the computationally expensive parameter sweeps that are traditionally done. We conduct a parameter recovery study to confirm that the LBA can recover ACT‐R parameters from simulated data. Then, as a proof of concept, we use the LBA to estimate ACT‐R parameters from an empirical dataset. The resulting parameter estimates provide a cognitively meaningful explanation for observed differences in behavior over time and between individuals. In addition, we find that the mapping between ACT‐R and LBA lends a more concrete interpretation to ACT‐R's latency factor parameter, namely as a measure of response caution. This work contributes to a growing movement towards integrating formal modeling approaches in cognitive science.
Successful management of severe carprofen toxicity with manual therapeutic plasma exchange in a dog
Authors: Buseman Miranda , Blong April E. , Walton Rebecca A. L.
Published: May 2022

Objective

To report the use of manual therapeutic plasma exchange (TPE) in a dog with severe carprofen toxicity.

A 12‐year‐old neutered female Pembroke Welsh Corgi weighing 20 kg was evaluated after ingesting 223 mg/kg of carprofen. Emesis was attempted with apomorphine at the primary care veterinarian but was unsuccessful, and a dose of activated charcoal with sorbitol was administered. On presentation to the referral center, approximately 8 hours after ingestion, the dog's physical examination revealed mild abdominal discomfort but was otherwise unremarkable. Treatment consisted of a combination of supportive care including activated charcoal with sorbitol, cholestyramine, IV lipid emulsion, and manual TPE. Blood samples were collected prior to the initiation of manual TPE and at the completion of 12 exchange cycles. Carprofen levels were determined by high‐pressure liquid chromatography. A 57% decrease in carprofen levels was achieved with the combination of activated charcoal, cholestyramine, IV lipid emulsion, and manual TPE. The dog did not develop organ dysfunction secondary to toxicity and was discharged 4 days after ingestion.

New or Unique Information Provided

This report describes the successful decrease of plasma carprofen in a dog with the combination of decontamination techniques and manual TPE. While TPE has been previously reported as a successful therapeutic in dogs with nonsteroidal anti‐inflammatory toxicity, including carprofen, equipment and expertise of this platform is not readily available. Manual TPE is technically simple and can be performed in any hospital with a large blood centrifuge.
Modeling and Reinforcement Learning Control of an Autonomous Vehicle to Get Unstuck From a Ditch
Authors: Manring Levi H. , Mann Brian P.
Published: May 2022

Autonomous vehicle control approaches are rapidly being developed for everyday street-driving scenarios. This article considers autonomous vehicle control in a less common, albeit important, situation “a vehicle stuck in a ditch.” In this scenario, a solution is typically obtained by either using a tow-truck or by humans rocking the vehicle to build momentum and push the vehicle out. However, it would be much more safe and convenient if a vehicle was able to exit the ditch autonomously without human intervention. In exploration of this idea, this article derives the governing equations for a vehicle moving along an arbitrary ditch profile with torques applied to front and rear wheels and the consideration of four regions of wheel-slip. A reward function was designed to minimize wheel-slip, and the model was used to train control agents using Probabilistic Inference for Learning COntrol (PILCO) and deep deterministic policy gradient (DDPG) reinforcement learning (RL) algorithms. Both rear-wheel-drive (RWD) and all-wheel-drive (AWD) results were compared, showing the capability of the agents to achieve escape from a ditch while minimizing wheel-slip for several ditch profiles. The policy results from applying RL to this problem intuitively increased the momentum of the vehicle and applied “braking” to the wheels when slip was detected so as to achieve a safe exit from the ditch. The conclusions show a pathway to apply aspects of this article to specific vehicles.
Nanoindentation Size Effects in Lithiated and Sodiated Battery Electrode Materials
Authors: Papakyriakou Marc , Lu Mu , Xia Shuman
Published: May 2022

Deformation and stress in battery electrode materials are strongly coupled with diffusion processes, and this coupling plays a crucial role in the chemical and structural stability of these materials. In this work, we performed a comparative study of the mechanical characteristics of two model materials (lithiated and sodiated germanium (Ge)) by nanoindentation. A particular focus of the study was on the indentation size effects and harnessing them to understand the chemo-mechanical interplay in these materials. While the quasi-static measurement results showed no significant size dependence, size effects inherent in the nanoindentation creep response were observed and utilized to investigate the deformation mechanism of each material. Supplemented by computational chemo-mechanical modeling, we found that lithiated Ge creeps through a stress-gradient-induced diffusion (SGID) mechanism but a model combining the SGID and conventional shear transformation deformation (STD) mechanisms was needed to capture the creep behavior of sodiated Ge. Broadly, this work reveals the importance of stress-diffusion coupling in governing the deformation of active electrode materials and provides a quantitative framework for characterizing and understanding such coupling.
Probabilistic Digital Twin for Additive Manufacturing Process Design and Control
Authors: Nath Paromita , Mahadevan Sankaran
Published: May 2022

This paper proposes a detailed methodology for constructing an additive manufacturing (AM) digital twin for the laser powder bed fusion (LPBF) process. An important aspect of the proposed digital twin is the incorporation of model uncertainty and process variability. A virtual representation of the LPBF process is first constructed using a physics-based model. To enable faster computation required in uncertainty analysis and decision-making, the physics-based model is replaced by a cheaper surrogate model. A two-step surrogate model is proposed when the quantity of interest is not directly observable during manufacturing. The data collected from the monitoring sensors are used for diagnosis (of current part quality) and passed on to the virtual representation for model updating. The model updating consists of Bayesian calibration of the uncertain parameters and the discrepancy term representing the model prediction error. The resulting digital twin is thus tailored for the particular individual part being produced and is used for probabilistic process parameter optimization (initial, before starting the printing) and online, real-time adjustment of the LPBF process parameters, in order to control the porosity in the manufactured part. A robust design optimization formulation is used to minimize the mean and standard deviation of the difference between the target porosity and the predicted porosity. The proposed methodology includes validation of the digital twin in two stages. Validation of the initial model in the digital twin is performed using available data, whereas data collected during manufacturing are used to validate the overall digital twin.
Inflated Cone Experiment for High-Throughput Characterization of Time-Dependent Polymer Membranes
Authors: Bugra Ozdemir Veli , Kwok Kawai
Published: May 2022

Long-term behavior of polymer membranes in the nonlinear regime is probed by strain histories under various stress levels. Current characterization methods for polymer membranes impose a uniform stress field and hence require a series of long-duration tests to be conducted, which poses a significant experimental challenge. Here, we present the inflated cone method to generate a continuous spectrum of strain histories under various stresses in a single experiment. By imposing a known stress gradient and utilizing a full-field strain measurement technique, the inflated cone method provides a high-throughput approach for extracting time-dependent data of polymer membranes. The method is suitable for studying nonlinear time-dependent deformations under a biaxial stress state. The stress range and ratio can be easily modulated by cone geometry design. We demonstrate the utility of the method through creep-recovery tests carried out on a polyethylene thin film. The proposed experimental method is highly beneficial for the development of nonlinear viscoelastic and viscoplastic models.
High-energy x-ray photoelectron spectroscopy spectra of InP measured by Cr Kα
Authors: Zborowski C. , Vaesen I. , Vanleenhove A. , Hoflijk I. , Artyushkova K. , Conard T.
Published: May 2022

Single crystal InP was analyzed using high-resolution high-energy x-ray photoelectron spectroscopy (HAXPES). The HAXPES spectra of InP obtained using monochromatic Cr Kα radiation at 5414.8 eV include two survey scans (Al Kα and Cr Kα) and high-resolution spectra of In 2s, In 2p3/2, In 3s, In 3p, In 3d, In 4s, In 4d, P 1s, P 2s, and P 2p.
Acoustic scattering by a small obstacle in the time domain
Authors: Martin P. A.
Published: May 2022

Acoustic scattering by small obstacles in the frequency domain has an extensive literature, going back to Lord Rayleigh in the 19th century. However, analogous results in the time domain are rare. A typical problem concerns the interaction of a sound pulse with a small obstacle. The beginning of a theory for such problems is outlined, using time domain boundary integral equations. A key question is “What does it mean for an obstacle to be ‘small’?”
Passive cavitation detection with a needle hydrophone array
Authors: Jiang Zheng , Sujarittam Krit , Ilbilgi Yildiz Betul , Dickinson Robert J. , Choi James
Published: May 2022

Therapeutic ultrasound and microbubble technologies seek to drive systemically administered microbubbles into oscillations that safely manipulate tissue or release drugs. Such procedures often listen to and then utilize microbubble emissions to control the microbubble activity. However, most sensors reported introduce large distortions to the acoustic signal. Acoustic shockwaves, a key emission from microbubbles, are largely absent in reported recordings. Here, we present a needle hydrophone array better suited for monitoring ultrasound-driven microbubble activities. The array consisted of eight polyvinylidene fluoride (PVDF, diameter: 2 mm) needle hydrophones. Each needle had a flexible coaxial wire at its end allowing flexibility to fit into a 3D-printed scaffold. Using this array, we monitored microbubbles exposed to ultrasound pulses (center frequency: 0.5 MHz, peak-rarefactional pressure: 130–-597 kPa, pulse length: 4 cycles). Our tests revealed that each needle had a broadband frequency response (1–15 MHz) and was able to capture shock waveforms generated by bubbles. The signal-to-noise ratio of the array was approximately 2 times higher than individual hydrophones. Also, the array could localize microbubble activities and determine the cavitation threshold. Thus, the array accurately monitored and localized microbubble activities, and may be an important technological step towards safer and more effective treatments.
Prediction of shooter localization accuracy in an urban environment
Authors: Still Luisa , Oispuu Marc
Published: May 2022

The use of acoustic sensor networks for shooter localization can provide a vital contribution to situational awareness in urban environments. During mission planning, the performance prediction for acoustic shooter localization plays a central role as it allows an optimization of the sensor positions in a sensor network. Instead of a sound propagation-based approach, in our work we focus on an information theoretical analysis using the Cramér-Rao bound to predict the achievable shooter localization accuracy. Through this approach, we have shown that accounting for incomplete and heterogeneous acoustic measurement data sets leads to maximization of the fusion gain and consequently to improved achievable localization accuracy. We validated the match between predicted and actual experimental performance in free-field measurements with supersonic gunshots including varying sensor-to-shooter geometries, weapon types, and various measurement types. By measuring signatures of impulsive gas cannon shots in urban terrain, we analyzed the effect of buildings to the sensor performance and achieved a significant improvement in the localization performance prediction by adjusting the sensor model depending on whether line-of-sight or non-line-of-sight conditions to the target exists.
Role of multiple reflections in identifying street canyons in microscale urban spaces
Authors: Davis Dorian , Mandjoupa Lirane , Gaye Samba , Mohamed Shehabaldin , Etochukwu Etochukwu , Mahmoud Wagdy , Wan Lei , Denis Max
Published: May 2022

In this work, geometric acoustic numerical modeling of sound propagation in a micro-scale urban spaces is presented. The resultant sound propagation demonstrates an amplification of sound and increased reverberation time, due to the multiple reflections in the micro-scale urban spaces. Comparative analysis of the sound field acoustic parameters for various length and width between geometric boundaries can differentiate street canyons from other urban micro-scale spaces. Specifically, sound pressure level results are strongly influenced by the geometric configuration and material properties of the geometric boundary surfaces. The results and limitations of the geometric numerical method for predicting sound propagation in urban environments are discussed.
Sonofragmentation and sonocrystallization: How solids break and make in cavitating liquids
Authors: Suslick Kenneth S.
Published: May 2022

Mechanical action can produce dramatic physical and mechanochemical effects when the energy is spatially or temporally concentrated. The application of ultrasound to crystallization (i.e., sonocrystallization) can dramatically affect the properties of the crystalline products. Sonocrystallization induces rapid nucleation, generally yields smaller crystals of a more narrow size distribution compared to quiescent crystallizations, and has become increasingly important in the pharmaceutical industry for the preparation of APIs (active pharmaceutical ingredients). The control of morphology of the crystallization process is critical to reproducible dose response for APIs and is under increasing scrutiny in pharmaceutical manufacturing by the FDA. Ultrasound can induce significant improvement in the uniformity of crystallite size and rates of crystallization. We have developed a mechanistic understanding of the origin of these phenomena and begun to separate the details of the effects of ultrasound on nucleation, mass transport, shockwave fragmentation of crystallites, and inter-particulate collision. Decoupling experiments were performed to confirm that interactions between shockwaves and crystals are the main contributors to crystal breakage. We have discovered a mechanochemical extension the Bell–Evans–Polanyi principle: activation energies for solid fracture correlate with the binding energies of the solids.
Spatial, temporal, and spectral variability of ambient noise in the Arctic
Authors: Robinson Calder L. , Hines Paul C. , Martin S. B. , Barclay David R.
Published: May 2022

Ambient noise in the Arctic exhibits significant spatial, temporal and spectral variability. This poses significant challenges for passive sonar performance estimation since the probability of detection is measured against this noise background. This is exacerbated by the relative paucity of measurements made in this remote region with which to estimate the statistics that describe the noise variability. To help address this deficiency, ambient noise measurements were collected during a year-long deployment for the CAATEX trial conducted in 2020–2021. In this paper, the measurements are summarized and the spatial, temporal and spectral variability of the ambient noise is presented.
A systematic investigation to assess the merits of measurement preconditions critical to speech privacy standards
Authors: Koukounian Viken
Published: May 2022

As with any field of science, the limits of theory are regularly tested to make way for more reliable testing standards. However, without a defined understanding of scope and purpose, the line between theory and practice—that which is already obscure—becomes increasingly difficult to identify. In the following investigation, the author reviews the scope and purpose of certain acoustical standards (ASTM E90, E336, E1130, E1573, E2638, and ANSI/ASA S12.2, S12.72) to clarify the context for which meaningful guidance is needed. More specifically, topics of interest include (1) effects of measurement locations and positions, (2) effects of measurement procedure, (3) effects of measurement instrumentation, (4) differences between operators, and (5) effects of architectural features on sound (i.e., spatial, spectral and temporal properties). To offer resolute understanding of the impact of each recommendation, the measurement methods within this investigation exceed those provided by the Standards. This provision is intended to afford meaningful insight as to the theoretical and practical limitations of the measurement of sound in the built environment—in contrast to the more limited data that would be available if testing is in accordance with the relevant Standards. The variability due to each guideline is quantified and reported.
Comparing testing methodologies of speech privacy class in closed offices
Authors: Toubar Rewan , Mackenzie Roderick , Lee Joonhee
Published: May 2022

Speech privacy is a principal research area in speech communication. The term "speech privacy" is generally interpreted a condition where speech cannot be readily understood by, but may be audible to, an unintended listener. The need to prevent sound from intruding into adjacent spaces in both closed and open-plan settings is a concern in various office buildings. Speech privacy is essentially a function of the signal-to-noise ratio, comprising the noise reduction between source and receiver positions, and the masking effective of background noise. Speech Privacy Class (SPC) is one of the commonly used metrics for speech privacy assessment in closed plan offices in North America. However, there is a reluctance to use SPC between closed rooms due to laborious testing requirements as per ASTM E2638; there is a supposed preference to use either Speech Privacy Potential (SPP) based on simpler NIC testing, or to use Articulation Index (AI) despite the AI being created solely for testing open-plan settings. The ASTM E2638-10 standard SPC testing procedure does not assume a diffuse field in the receiving space but rather evaluates the performance at each potential eavesdropping location on the basis that there may be an intentional listener. Thus, to better apply the SPC to unintended listening and speech privacy in typical commercial spaces, the goal is to compare the current methodology as per ASTM E2638-10 with alternative sampling methods considering the talker location and unintended listening positions outside the source room.
Superresolution imaging of microvasculature at the capillary level using nanobubble contrast agents
Authors: Exner Agata A. , Wegierak Dana , Bayat Mahdi
Published: May 2022

In this work, we describe applications of nanobubbles in superresolution imaging. Conventional ultrasound localization microscopy (ULM) techniques require sparse scatterers in the form of echogenic microbubbles (MB, ∼1–10 μm diameter). ULM enables imaging of capillaries larger than ∼50 μm in diameter but becomes too time consuming in smaller capillaries due to insufficient MB density. A viable alternative for microvascular imaging may be the use of submicron bubbles, or nanobubbles (NBs). NBs are ∼100i–500 nm in diameter and have a particle density 5 orders of magnitude higher than MBs without associated attenuation artifacts. In addition to strong nonlinear response, under some conditions NBs can produce SNR linear signals stronger than erythrocytes. This allows for formulating a superresolution imaging problem using computational approaches suitable for dense sources instead of relying on physical sparsity. With much smaller sizes compared to MBs, NBs can access the smallest capillaries at much higher concentrations (∼1011), offering enhanced detection and faster superresolution acquisition. In addition, NB nonlinear signals can be decomposed to elucidate intravascular and extravasation into tissues with vascular hyperpermeability, such as tumors. Thus, when combined with appropriate processing, NBs can provide information about vascular architecture and extravascular transport which is not achievable with MBs.
A passive radio frequency excited acoustic transducer
Authors: Thompson Charles , Hu Lejun , Remillard Grace , Chandra Kavitha , Paradorn Vacharaporn , Lawal Azizat
Published: May 2022

The physical processes that govern the operation of a passive acoustic transducer driven into operation by a broadcast radio-frequency electromagnetic wave are presented. The transducer is comprised of a re-entrant cavity resonator operating in its resonant TEM mode and a sensing membrane. By displacing the membrane using the acoustic pressure, one can generate an amplitude modulated radio frequency signal proportional to the product of the displacement and the excitation signal. One may use the backscattered electromagnetic signal to recover the audio signal. The results for power generation, sound transduction, and radio-frequency backscatter transmission of the audio signal are presented.
One-dimensional modeling of the air motion transformer
Authors: Riccardi Peter J. , Blanford Thomas E.
Published: May 2022

The Air Motion Transformer (AMT), since its invention in the 1970s, has found application as a high-frequency tweeter for loudspeakers. It is perceived as reproducing audio with superior clarity and fidelity of transients compared to moving coil tweeter designs. It is well known that many factors, such as frequency response and properties of nonlinear distortion products, influence human perfect of audio quality. Despite the perceived superiority of AMT performance, few studies have investigated this transducer to accurately model their operation and understand the physical mechanisms that influence their sound quality. This presentation will describe a one-dimensional model for an AMT loudspeaker that can be used to predict both linear and nonlinear behavior of the device. The model will be compared to measured data from commercially available AMT tweeters. Sources of nonlinear distortion in the AMT device that may influence perceived sound quality will be discussed. The similarities and differences between the electroacoustic properties of the AMT and comparable moving coil tweeters, and how these relate to sound quality, will also be discussed.
Speed of velum movement during nasal segments and rest intervals: A cineradiographic study of French and English speech
Authors: Islam Md Jahurul , de Boer Gillian , Gick Bryan
Published: May 2022

While opening/closing of the velopharyngeal port (VPP) in speech has been much studied, the speed of these movements has been largely overlooked. The present study compares opening/closing velocities of the VPP in French and English, testing relation to distance traveled and speech-related versus physiological movements. Running speech samples from nine Quebecois French speakers and four Canadian English speakers were obtained from the Université Laval X-ray videofluorography database [Munhall et al., J. Acoust. Soc. Am., 98(2), 1222–1224 (1995)]. Using ImageJ software, we tracked VPP opening/closing movements during two types of events: phonologically nasal segments and rest intervals between chunks of speech. We calculated velocity of VPP opening/closing during these events and analyzed the data using linear mixed-effects models to identify differences between the nasals and rest intervals as well as for any cross-linguistic differences. Results indicated that: (1) VPP closure was faster following English nasals than French nasals; (2) VPP opening was faster than closure for rest intervals in French; and (3) VPP opening/closing speeds were faster coming into/out of rest position than into/out of nasals in French. Preliminary cross-language observations support a correspondence between velocity and distance. [Work supported by NIH and NSERC.]
Sound quality metrics for improved prediction of hospital sleep disruption
Authors: Swift S. Hales , Solet Joanne
Published: May 2022

Most policy, including for the healthcare environment, uses A-weighted decibels as a standard metric. A-weighting is, thus, treated as a catch-all intended to represent all or most relevant human factors. However, for protecting sleep in the healthcare environment and its attendant recuperative benefits, A-weighted metrics neglect a great deal of essential information. To illustrate this, a dataset from a prior study of sleep disruption resulting from hospital noises measured using polysomnography [Sleep disruption due to hospital noise, Buxton et al. (2012)] is reanalyzed using measures of loudness, sharpness, and tonality. Linear combinations of these variables result in improved prediction of sleep state transitions relative to the A-weighted measure initially employed. Sound quality metrics can provide additional insight into how best to ensure a sonic environment conducive to a good night’s sleep and can, thus, help decision makers build an environment that delivers restorative sleep in the service of restoration of health. [Work supported by SAND2022-0675 A.]