bluuebunny/crossref_metadata_2025 huggingface dataset:
Directivity of binaural noise reduction in spatial multiple noise-source arrangements for normal and impaired listeners
Authors: Peissig Jürgen , Kollmeier Birger
Published: July 2002

Speech reception thresholds (SRTs) were obtained for different azimuths of up to three interfering sound sources in a simulated (“virtual”) spatial arrangement. For the SRT measurements a fast subjective threshold assessment method was used. The reduction in SRT relative to the reference threshold caused by spatial separation of target and interference signal is called the intelligibility level difference (ILD). For normal listeners, the maximum ILD was achieved at 105° or 255° azimuth of a single noise source when the target emanated from the front (0° azimuth). The ILD decreased rapidly if the number of interfering signals was increased and if they were located on opposite sides of the head. When using continuous speech as interference, this decrease of ILD was less pronounced. These findings indicate that the binaural system can suppress interference from only one azimuthal region at a time and can utilize temporal pauses in the interference to suppress a second interference from a different direction. For eight sensorineural impaired listeners, the maximum attainable ILD for one interfering noise source was reduced in a way not predictable from the audiogram. The ability to exploit pauses in the signal of an interfering talker was also reduced. Hence, hearing-impaired listeners are handicapped in realistic spatial interference situations both by an increased monaural SRT and a reduced binaural noise reduction ability.
Exact solution for one-dimensional acoustic fields in ducts with a quadratic mean temperature profile
Authors: Kumar B. Manoj , Sujith R. I.
Published: July 2002

The purpose of this Letter is to present an exact analytical solution for sound propagation in ducts with a quadratic mean temperature profile. Using appropriate transformations, the one-dimensional wave equation for ducts with an axial mean temperature gradient was reduced to the hypergeometric differential equation, whose solution can be expressed in terms of hypergeometric functions. The analysis neglects the effects of mean flow and is therefore valid only for small mean Mach numbers.
Spectral cues for sound localization in cats: A model for discharge rate representations in the auditory nerve
Authors: May Bradford J. , Huang Aileen Y.
Published: July 2002

Neural representations of pinna-based spectral cues for sound localization were modeled by simulating auditory nerve discharge rates to noise bursts that had been shaped by filtering properties of the cat’s head-related transfer functions (HRTFs) at 179 locations in the frontal field. The auditory nerve model transformed spectral differences between HRTFs into simulated neural rate differences. Linear equations for this transformation were developed from actual auditory nerve responses to a limited subset of HRTF-filtered noise bursts [Rice et al., J. Acoust. Soc. Am. 97, 1764–1776 (1995)]. Signal detection methods were used to investigate simulated neural responses to pairwise changes between HRTFs. The quality of neural representation for these changes, in terms of d′ values, declined when the reference HRTF was moved from a central location (0° AZ, 0° EL) to a large positive azimuth in the horizontal plane (75° AZ, 0° EL) or a high elevation in the median plane (0° AZ, 75° EL). Most simulated responses exhibited large d′ values for comparisons of contralateral versus ipsilateral azimuths, or eccentric versus frontal elevations. This rate information resulted from directionally dependent changes in the overall gain of HRTFs. In addition, fibers with best frequency (BF: the frequency of greatest sensitivity for individual fibers) between 5 and 18 kHz showed large d′ values for HRTF contrasts in the immediate frontal field because of the effects of spectral notches (i.e., sharp drops in gain over a narrow frequency range). Spectral notches also played a prominent role in simulations that required identification of HRTF location in the absence of a fixed reference stimulus. These modeling results correspond well with previously described patterns in the cat’s localization behaviors.
Medial efferent inhibition suppresses basilar membrane responses to near characteristic frequency tones of moderate to high intensities
Authors: Russell Ian J. , Murugasu Euan
Published: July 2002

Efferent inhibition of low and medium speontaneous-rate fiber activity in response to characteristic frequency (CF) tones is greater at levels between 50 and 75 dB SPL than at lower levels, and even occurs at levels of 100 dB SPL [Guinan and Stankovic, J. Acoust. Soc. Am. 100, 1680–1690 (1996)]. The self-mixing effect of a laser diode was used to measure tone-evoked, basilar membrane (BM) displacements in the basal turn of the guinea pig cochlea during electrical stimulation of the medial efferent system. Efferent stimulation suppresses BM displacement and, for frequencies close to the CF of the measurement site and above, attenuation of tone-evoked displacements appears to be greatest for levels between 50 and 75 dB SPL, and efferent attenuation could exceed 10 dB SPL for tones at 90 dB SPL. By comparison, the attenuation of the BM vibrations caused by tones at frequencies below CF was found to be greatest for low sound pressure levels. The findings of Guinan and Stankovic therefore have their origin in events present in the vibrations of the BM.
Estimating articulation scores
Authors: Rankovic Christine M. , Levy Robin M.
Published: July 2002

The ability of listeners to estimate articulation scores for lists of nonsense syllables was evaluated. Normal-hearing subjects were presented with lists of from 50 to 60 nonsense syllables that were degraded with various amounts of noise or filtering and were instructed to estimate consonant-correct scores for each condition. To provide a reference for estimating, subjects were shown the accurate orthographic representation of the syllable on a computer monitor to compare with the auditory presentation. The printed version was displayed either simultaneously with the auditory presentation or 500 ms after the offset of the syllable. Estimates were collected on two occasions to examine test–retest reliability, and actual percent-correct scores were obtained to check the accuracy of the estimates. Most subjects overestimated actual scores when the printed representation was provided simultaneously, but estimates were strikingly similar to actual scores when the printed representation was delayed. The delay appeared to prevent the printed representation from favorably biasing the reception of the syllable. The average of two or three estimates gave highly repeatable results for both visual displays. Crossover frequencies derived from the filtered-speech conditions were within the range reported in the literature. This supports the conclusion that subjects based their estimates on the recognition of speech sounds rather than other percepts associated with the speech-in-noise conditions such as loudness of the noise. The estimation procedure permits the collection of articulation scores in much less time than required by traditional test procedures.
Temporal processing of the pitch of complex tones
Authors: White Louise J. , Plack Christopher J.
Published: July 2002

The effect of tone duration on fundamental frequency (F0) discrimination is greater for complexes containing unresolved harmonics than for those containing resolved harmonics [Plack and Carlyon, J. Acoust. Soc. Am. 98, 1355–1364 (1995)]. Three experiments explored this effect further. The first experiment measured sensitivity (as d′) to fundamental frequency (F0) differences for two complexes, both with an F0 of 250 Hz. The first complex was low-pass filtered at 1875 Hz to create a resolved complex and the second was bandpass filtered between 5500 and 7500 Hz to create an unresolved complex. The harmonics for the resolved complex were selected so that no two harmonics were the same between the two observation intervals. Performance for both complexes was measured for tone durations of 20, 40, 80, and 160 ms. For the unresolved complex, the effect of duration was greater than that for the resolved complex and greater than the predictions of a “multiple-looks” model assuming either peripheral (before sampling) or central (after combining samples) sources of variance. The second experiment replicated these results using an F0 of 62.5 Hz with the cutoff frequencies of the bandpass filters divided by four, confirming that the effect is related to resolvability and not to spectral region. In the final experiment, F0 discrimination for pairs of complexes separated by a temporal gap was measured relative to that for one complex. Performance for the resolved and unresolved complexes was similar: Very little effect of gap duration was observed and the results were consistent with the predictions of the peripheral-variance multiple-looks model. Taken together, the results suggest that the pitch mechanism for resolved harmonics uses a relatively short sampling window of around 20 ms, while the mechanism for unresolved harmonics may use a more complex strategy for optimizing the combination of information over time, perhaps involving a flexible integration time.
Benefits of linear amplification and multichannel compression for speech comprehension in backgrounds with spectral and temporal dips
Authors: Moore Brian C. J. , Peters Robert W. , Stone Michael A.
Published: July 2002

People with cochlear hearing loss have markedly higher speech-receptions thresholds (SRTs) than normal for speech presented in background sounds with spectral and/or temporal dips. This article examines the extent to which SRTs can be improved by linear amplification with appropriate frequency-response shaping, and by fast-acting wide-dynamic-range compression amplification with one, two, four, or eight channels. Eighteen elderly subjects with moderate to severe hearing loss were tested. SRTs for sentences were measured for four background sounds, presented at a nominal level (prior to amplification) of 65 dB SPL: (1) A single female talker, digitally filtered so that the long-term average spectrum matched that of the target speech; (2) a noise with the same average spectrum as the target speech, but with the temporal envelope of the single talker; (3) a noise with the same overall spectral shape as the target speech, but filtered so as to have 4 equivalent-rectangular-bandwidth (ERB) wide spectral notches at several frequencies; (4) a noise with both spectral and temporal dips obtained by applying the temporal envelope of a single talker to speech-shaped noise [as in (2)] and then filtering that noise [as in (3)]. Mean SRTs were 5–6 dB lower (better) in all of the conditions with amplification than for unaided listening. SRTs were significantly lower for the systems with one-, four-, and eight-channel compression than for linear amplification, although the benefit, averaged across subjects, was typically only 0.5 to 0.9 dB. The lowest mean SRT (−9.9 dB, expressed as a speech-to-background ratio) was obtained for noise (4) and the system with eight-channel compression. This is about 6 dB worse than for elderly subjects with near-normal hearing, when tested without amplification. It is concluded that amplification, and especially fast-acting compression amplification, can improve the ability to understand speech in background sounds with spectral and temporal dips, but it does not restore performance to normal.
Acoustic eigenfrequencies in a spheroidal cavity with a concentric penetrable sphere
Authors: Kokkorakis Gerassimos C. , Roumeliotis John A.
Published: July 2002

The acoustic eigenfrequencies fnsm in a spheroidal cavity containing a concentric penetrable sphere are determined analytically, for both Dirichlet and Neumann conditions in the spheroidal boundary. Two different methods are used for the evaluation. In the first, the pressure field is expressed in terms of both spherical and spheroidal wave functions, connected with one another by well-known expansion formulas. In the second, a shape perturbation method, this field is expressed in terms of spherical wave functions only, while the equation of the spheroidal boundary is given in spherical coordinates. The analytical determination of the eigenfrequencies is possible when the solution is specialized to small values of h=d/(2R2), (h≪1), with d the interfocal distance of the spheroidal boundary and 2R2 the length of its rotation axis. In this case exact, closed-form expressions are obtained for the expansion coefficients gnsm(2) and gnsm(4) in the resulting relation fnsm(h)=fns(0)[1+h2gnsm(2)+h4gnsm(4)+O(h6)]. Analogous expressions are obtained with the use of the parameter v=1−(R2/R2′)2, (|v|≪1), with 2R2′ the length of the other axis of the spheroidal boundary. Numerical results are given for various values of the parameters.
Factors affecting the loudness of modulated sounds
Authors: Moore Brian C. J. , Vickers Deborah A. , Baer Thomas , Launer Stefan
Published: July 2002

Loudness matches were obtained between unmodulated carriers and carriers that were amplitude modulated either periodically (rates between 2 and 32 Hz, modulation sinusoidal either on a linear amplitude scale or on a dB scale; the latter is called dB modulation) or with the envelope of the speech of a single talker. The carrier was a 4-kHz sinusoid, white noise, or speech-shaped noise. Both normally hearing subjects and subjects with cochlear hearing loss were tested. Results were expressed as the root-mean-square (rms) level of the modulated carrier minus the level of the unmodulated carrier at the point of equal loudness. If this difference is positive, this indicates that the modulated carrier has a higher rms level at the point of equal loudness. For normally hearing subjects, the results show: (1) For a 4000-Hz sinusoidal carrier, the difference was slightly positive (averaging about 0.7 dB). There was no significant effect of modulation rate or level over the range 20–80 dB SL. (2) For a speech-shaped noise or white noise carrier, the difference was close to zero, although for large modulation depths it tended to be negative. There was no clear effect of level (over the range 35–75 dB SPL) or modulation rate. For the hearing-impaired subjects, the differences were small, but tended to be slightly negative for both the 4000-Hz carrier and the noise carriers, when the modulation rate was above 2 Hz. Again, there was no clear effect of overall level. However, for dB modulation, the differences became more negative with increasing modulation depth. For modulation rates in the range 4–32 Hz, the results could be fitted reasonably well using the assumption that the loudness of modulated sounds is based on the rms value of the time-varying intensity of the response of the basilar membrane (taking into account the compression that occurs in the normal cochlea). The implications of the results for the fitting of multi-band compression hearing aids and for the design of loudness meters are discussed.
The role of spectral and periodicity cues in auditory stream segregation, measured using a temporal discrimination task
Authors: Vliegen Joyce , Moore Brian C. J. , Oxenham Andrew J.
Published: July 2002

In a previous paper, it was shown that sequential stream segregation could be based on both spectral information and periodicity information, if listeners were encouraged to hear segregation [Vliegen and Oxenham, J. Acoust. Soc. Am. 105, 339–346 (1999)]. The present paper investigates whether segregation based on periodicity information alone also occurs when the task requires integration. This addresses the question: Is segregation based on periodicity automatic and obligatory? A temporal discrimination task was used, as there is evidence that it is difficult to compare the timing of auditory events that are perceived as being in different perceptual streams. An ABA ABA ABA… sequence was used, in which tone B could be either exactly at the temporal midpoint between two successive tones A or slightly delayed. The tones A and B were of three types: (1) both pure tones; (2) both complex tones filtered through a fixed passband so as to contain only harmonics higher than the 10th, thereby eliminating detectable spectral differences, where only the fundamental frequency (f0) was varied between tones A and B; and (3) both complex tones with the same f 0, but where the center frequency of the spectral passband varied between tones. Tone A had a fixed frequency of 300 Hz (when A and B were pure tones) or a fundamental frequency (f0) of 100 Hz (when A and B were complex tones). Five different intervals, ranging from 1 to 18 semitones, were used. The results for all three conditions showed that shift thresholds increased with increasing interval between tones A and B, but the effect was largest for the conditions where A and B differed in spectrum (i.e., the pure-tone and the variable-center-frequency conditions). The results suggest that spectral information is dominant in inducing (involuntary) segregation, but periodicity information can also play a role.
Music cognition and Williams Syndrome
Authors: Levitin Daniel , Bellugi Ursula
Published: July 2002

New studies of the musical abilities of individuals with Williams Syndrome (WMS) are presented. WMS is associated with poor spatial, quantitative, and reasoning abilities, coupled with excellent face processing and relatively preserved language abilities. WMS individuals tend to have richer (larger and more colorful) vocabularies than would be expected for their mental age and tend to be more emotionally expressive than normals. There have long been anecdotal reports of increased musicality in WMS (many of them are competent musicians who play from memory) and these are supported by the finding that the planum temporale (PT, a region adjacent to A1) is proportionately enlarged in WMS; in addition, the PT is unusually asymmetric in WMS, with the left side enlarged in a similar fashion to that found in professional musicians. The authors report new studies of rhythm production and memory for music in WMS. The results suggest that this domain of cognitive ability may also be relatively preserved. These findings provide additional evidence that music constitutes a domain-specific higher-level system of expertise in humans, perhaps independent of other mental abilities.
Relative loudness perception of low and high frequency sounds in the open and occluded ear
Authors: Keidser Gitte , Katsch Rickard , Dillon Harvey , Grant Frances
Published: July 2002

A comparison of published equal loudness contours indicates that different shapes are obtained at a comfortable level when the measurements are done in an occluded ear than when they are done in an open ear, even though all measurements are expressed as dB SPL at the eardrum. This paper presents the result from a loudness balancing test which confirms this observation. Eleven normal-hearing listeners balanced the level of a 500- and a 3000-Hz octave band babble-noise to the level of a 1500-Hz octave band babble-noise. The balancing test was completed in open and occluded ears using a loudspeaker and a hearing aid receiver, respectively. A probe tube microphone was used to measure the actual levels presented near the individual’s eardrum. The results show that an average of 10 dB higher level was selected for the 500-Hz octave band when listening with the occluded ear than when listening with the open ear. A large range of factors is discussed, but no physical explanation for the discrepancy was found. The findings could have consequences for psychoacoustic experiments and for the use of loudness measurements for hearing aid prescription.
Field characterization of therapeutic ultrasound phased arrays through forward and backward planar projection
Authors: Clement G. T. , Hynynen Kullervo
Published: July 2002

Spatial planar projection techniques propagate field measurements from a single plane in front of a transmitter to arbitrary new planes closer to or further away from the source. A linear wave vector frequency-domain projection algorithm is applied to the acoustic fields measured from several focused transducer arrays designed for ultrasound therapy. A polyvinylidene difluoride hydrophone is first scanned in a water tank over a plane using a three-dimensional positioning system to measure the complex pressure field as a function of position. The field is then projected to a series of new planes using the algorithm. Results of the projected fields are compared with direct measurements taken at corresponding distances. Excellent correlation is found between the projected and measured data. The method is shown to be accurate for use with phase-controlled field patterns, providing a rapid and accurate method for obtaining field information over a large spatial volume. This method can significantly simplify the characterization procedure required for phased-array application used for therapy. Most significantly, the wavefront propagated back to a phased array can be used to predict the field produced by different phase and amplitude settings of the array elements. A field back-projected to the source could be used as an improved source function in acoustic modeling.
Effect of masker harmonicity on informational masking
Authors: Oh Eunmi L. , Lutfi Robert A.
Published: July 2002

Detection thresholds for a tone in an unfamiliar tonal pattern can be greatly elevated under conditions of masker uncertainty [Neff and Green, Percept. Psychophys. 41, 409–415 (1987); Oh and Lutfi, J. Acoust. Soc. Am. 101, 3148 (1997)]. The present experiment was undertaken to determine whether harmonicity of masker tones can reduce the detrimental effect of masker uncertainty. Inharmonic maskers were comprised of m=2–49 frequency components selected at random on each presentation within 100–10 000 Hz, excluding frequencies between 920–1080. Harmonic maskers were comprised of frequency components selected at random within this same range, but constrained to have a fundamental frequency of 200 Hz. For inharmonic maskers the signal was a 1000-Hz tone. For harmonic-maskers the signal was a tone whose frequency was either harmonically (1000 Hz) or inharmonically (1047 Hz) related to the masker. In all conditions the amount of masking was greatest for m=20–40 components. At this point, harmonic maskers with harmonic signal produced an average of 9–12 dB less masking than inharmonic maskers. Harmonic maskers with inharmonic signal produced an average of 16–20 dB less masking.
Mechanics of Upper and Lower Yield Points of Amorphous Polymer Solids
Authors: Ito Katsuhiko
Published: July 2002

An experimental study was carried out on the phenomena of upper and lower yield points observed with hard, amorphous polymer solids below the glass-transition temperature. The effects of temperature, strain-rate, specimen shape, working strains, and annealing on the appearance of the upper and lower yield points were examined on epoxy cast resin (a three-dimensional cross-linked polymer) and on Celluloid (a linear polymer). It has been concluded that upper and lower yield points represent transient behavior, at a given moderate strain-rate, associated with mechanical heterogeneity, expressed as a distribution of relaxation times. Some applications of this yielding mechanism are discussed.
Classification of flow modes of viscoelastic fluids at a junction of two stratified laminar flow layers
Authors: Yamaguchi Hiroshi , Yasumoto Takeshi , Yamamoto Hideaki
Published: July 2002

Experiments were conducted in order to obtain flow states occurring at a junction of two laminar flow layers. In the present study, various combinations of Newtonian and non-Newtonian fluids for two laminar layers were tested in a relatively high-speed stratification process where the inertia of flow has to be taken into account. From experimental results, flow states at a junction with two different junction angles were classified into 10 flow modes and these modes were arranged to establish a three-dimensional mode map using a generalized Reynolds number and a Deborah number. It was revealed that a mutual relationship among inertial, viscous, and elastic effects is essential for interfacial deformation and instability in the stratified flow. It was also shown that the junction angles are important factors in the determination of flow modes appearing in the region of the junction.
Adeia
Authors: Poddighe Elisabetta , Esu Alberto
Published: December 2022

The Greek termadeiameans literally “absence of fear” and in Athenian Law indicates a special authorization or immunity from prosecution. The Athenian Assembly grantedadeiato authorize deliberation on an entrenched piece of legislation, and aboutatimoiand public debtors or to confer immunity from legal prosecution in criminal investigation.
Kalokagathia
Authors: Poddighe Elisabetta , Esu Alberto
Published: December 2022

The Greek wordkalokagathiadefined the moral excellence of thekaloi kagathoi(“honorable and good” men, καλοὶ κἀgamma;αθοί).
Iulius Africanus, Sextus
Authors: Adler William
Published: December 2022

The Christian polymath (Sextus) Iulius Africanus (ca. 160–240ce) is perhaps best known as the father of the Christian universal chronicle.
Beggars
Authors: Marsilio Maria S.
Published: December 2022

Ancient Greek and Roman authors distinguished conditions of poverty and beggary. The poor embraced honest hard labor in accordance with divine justice, carefully protecting their resources to make sure they always had enough. Conversely, beggars lived in idleness and did not earn their own wealth, making frequent appeals to others for the livelihood they lacked. Beggars typically were treated with revulsion, scorn, and mockery because of their inability to participate in fundamental values of community and society, such as work, justice, sacrifice, and reciprocity. Displays of sympathy and giving to beggars perhaps came more from non‐elites than from the upper‐classes.
Oasis Magna (Dakhleh Oasis)
Authors: Moss Jennifer Sheridan
Published: December 2022

The Dakhleh Oasis lies in the southwestern desert of Egypt, near the border with Libya. Human habitation dates back as far as the Middle Pleistocene Era, approximately 400,000 years ago. During the Old Kingdom it acted as an administrative center. Its heyday came in the Roman period, when the area supported a population of as many as 40,000 people, dozens of temples, and three major cities, Mothis, Trimithis, and Kellis.
Hecataeus of Miletus (Hekataios of Miletos)
Authors: Hunt Peter
Published: December 2022

Hecataeus of Miletos (ca. 560–480bce), a prominent intellectual and logographer of the Ionian Enlightenment, made a famous map and wrote two books: thePeriegesis, a pioneering work on geography, and theGenealogies, a rationalizing account of the age of heroes. His work survives only in fragments, but it represents an important step in the intellectual history of Greece and a crucial prose antecedent to Herodotus’History.
John Hyrcanus II (John Hyrkanos II)
Authors: Atkinson Kenneth
Published: December 2022

John Hyrcanus II was the youngest son of the Judaean monarch Alexander Jannaeus and queen Alexandra Salome.
C‐Group
Authors: Gatto Maria Carmela
Published: December 2022

The C‐Group was a Nubian culture (ca. 2550–1550
bce
). Its social system was tribal with an economy based on agro‐pastoralism and trade with Egypt. The current chronological framework consists of three phases: Early; Middle; and Late. Archaeological evidence concerning the C‐Group comes from both funerary and domestic contexts. These are respectively characterized by stone tumuli with associated offering places or chapels, and by enclosed villages with stone architecture. Cattle symbolism plays an important role in the ideological and religious spheres. The C‐Group disappeared when it was assimilated by the Egyptian culture during its invasion of Nubia in the New Kingdom.
Buthrotum/Bouthrotos (Butrint, Albania)
Authors: Hernandez David R.
Published: December 2022

Buthrotum (Bouthrotos) was an ancient seaport on the coast of Epirus (Epeiros) in northwestern Greece. Situated on the maritime trade route between Greece and Italy on the Strait of Otranto, the city held a longstanding geostrategic and commercial significance in the western Balkans. In Vergil's
Aeneid
(3.289–505), Buthrotum is described as a “little Troy” (
parva Troia
), founded by Helenus, son of king Priam. Owing to its purported Trojan ancestry, Augustus favored the city and refounded it under his own name as
colonia Augusta Buthrotum
.
Postumius Albinus, Aulus
Authors: Northwood Simon
Published: December 2022

A. Postumius A. f. A. n. Albinus was consul in 151
bce
and writer of a history of Rome and a poem, both in Greek.
Martianus Capella
Authors: Ramelli Ilaria L. E.
Published: December 2022

Martianus Capella was a poet, influenced by Neoplatonism, who probably came from Roman Africa (Carthage) and wrote his masterpiece,De Nuptiis Philologiae et Mercuriiin the early fifth centuryce, likely to have been before 439, although the dating of Martianus is difficult.
Calculating dose‐averaged linear energy transfer in an analytical treatment planning system for carbon‐ion radiotherapy
Authors: Wang Weiwei , Li Ping , Shahnazi Kambiz , Wu Xiaodong , Zhao Jingfang
Published: December 2022

Background

Compelling evidence shows the association between the relative biological effectiveness (RBE) of carbon‐ion radiotherapy (CIRT) and the dose averaged linear energy transfer (LETd). However, the ability to calculate the LETd in commercially available treatment planning systems (TPS) is lacking.

Purpose

This study aims to develop a method of calculating the LETd of CIRT plans that could be robustly carried out in RayStation (V10B, Raysearch, Sweden).

Methods

The calculation used the fragment spectra in RayStation for the CIRT treatment planning. The dose‐weighted averaging procedure was supported by the microdosimetric kinetic model (MKM). The MKM‐based pencil beam dose engine (PBA, v4.2) for calculating RBE‐weighted doses was reformulated to become a LET‐weighted calculating engine. A separate module was then configured to inversely calculate the LETd from the absorbed dose of a plan and the associated fragment spectra. In this study, the ion and energy‐specific LET table in the LETd module was further matched with the values decoded from the baseline data of the Syngo TPS (V13C, Siemens, Germany). The LETd distributions of several monoenergetic and modulated beams were calculated and validated against the values derived from the Syngo TPS and the published data.

Results

The differences in LETds of the monoenergetic beams between the new method and the traditional method were within 3% in the entrance and Bragg‐peak regions. However, a larger difference was observed in the distal region. The results of the modulated beams were in good agreement with the works from the published literature.

Conclusions

The method presented herein reformulates the MKM dose engine in the RayStation TPS to inversely calculate LETds. The robustness and accuracy were demonstrated.
Feature selection methods and predictive models in CT lung cancer radiomics
Authors: Ge Gary , Zhang Jie
Published: December 2022

Radiomics is a technique that extracts quantitative features from medical images using data‐characterization algorithms. Radiomic features can be used to identify tissue characteristics and radiologic phenotyping that is not observable by clinicians. A typical workflow for a radiomics study includes cohort selection, radiomic feature extraction, feature and predictive model selection, and model training and validation. While there has been increasing attention given to radiomic feature extraction, standardization, and reproducibility, currently, there is a lack of rigorous evaluation of feature selection methods and predictive models. Herein, we review the published radiomics investigations in CT lung cancer and provide an overview of the commonly used radiomic feature selection methods and predictive models. We also compare limitations of various methods in clinical applications and present sources of uncertainty associated with those methods. This review is expected to help raise awareness of the impact of radiomic feature and model selection methods on the integrity of radiomics studies.
Efficacy and Safety of the Bruton's Tyrosine Kinase Inhibitor Evobrutinib in Systemic Lupus Erythematosus: Results of a Phase II, Randomized, Double‐Blind, Placebo‐Controlled Dose‐Ranging Trial
Authors: Wallace Daniel J. , Dörner Thomas , Pisetsky David S. , Sanchez‐Guerrero Jorge , Patel Anand C. , Parsons‐Rich Dana , Le Bolay Claire , Drouin Elise E. , Kao Amy H. , Guehring Hans , Dall'Era Maria
Published: December 2022

Objective

Evobrutinib is a highly selective, orally administered Bruton's tyrosine kinase (BTK) inhibitor. The objective of this phase II, multicenter, randomized, double‐blind, placebo‐controlled trial was to evaluate the efficacy and safety of evobrutinib in patients with active autoantibody‐positive systemic lupus erythematosus (SLE).

Methods

Patients were diagnosed with SLE by either the Systemic Lupus International Collaborating Clinics criteria or at least four American College of Rheumatology criteria 6 months or more prior to screening, had an SLE Disease Activity Index‐2000 score of 6 or more, were autoantibody‐positive and on standard‐of‐care therapy. Randomization was 1:1:1:1 to oral evobrutinib 25 mg once daily (QD), 75 mg QD, 50 mg twice daily, or placebo. Primary efficacy endpoints were SLE responder index (SRI)‐4 response at week 52 and SRI‐6 response at week 52 in the high disease activity subpopulation. Safety endpoints included treatment‐emergent adverse events (TEAEs).

Results

A total of 469 patients were randomized and received at least one dose of evobrutinib or placebo at the time of primary analysis. Mean (SD) age at baseline was 40.7 (±12.3) years; 94.9% of patients were female. Neither primary efficacy endpoint was met. All doses of evobrutinib were well tolerated, and there was no clear dose effect on the incidence of reported TEAEs, or serious TEAEs, including severe infections.

Conclusion

This phase II, dose‐ranging trial in SLE failed to show a treatment effect of evobrutinib versus placebo at any dose. Evobrutinib was generally well tolerated, with no dose effect observed for TEAEs. These results suggest that BTK inhibition does not appear to be an effective therapeutic intervention for patients with SLE.
In Situ Neutron Diffraction Investigating Microstructure and Texture Evolution upon Heating of Nanostructured CoCrFeNi High‐Entropy Alloy
Authors: Liu Xiaojing , Han Jae-Kyung , Onuki Yusuke , Kuzminova Yulia O. , Evlashin Stanislav A. , Kawasaki Megumi , Liss Klaus-Dieter
Published: December 2022

Herein, in situ temperature‐dependent neutron experiments investigate the microstructural evolution of additively and conventionally manufactured CoCrFeNi high‐entropy alloys, as‐received, and after grain refinement through high‐pressure torsion. The evolution of texture after grain refinement and during heating is consistent with typical fcc metals. Both conventional and modified Williamson–Hall analyses reveal that major contributions of microstresses stem from dislocations. For the nanostructured material, three temperature regimes are identified on a heating ramp, namely, stress recovery up to 800 K, followed by recrystallization at 850–960 K, and normal grain growth above, in line with the physical change of hardness increase on recovery, decrease on recrystallization, and cutback to the as‐manufactured values after grain growth. The as‐printed material exposes higher dislocation density than as‐cast, reducing slightly upon heating, while there is limited temperature dependence on the lower dislocation density of the as‐cast specimen. Stored energies have been elaborated for residual stress and Bauschinger contributions, dislocation energy, grain boundary amounts, and vacancy contents with scenarios of vacancy expulsion leading to recrystallization. Ultimately, the fully recrystallized nanostructured material shows the lowest dislocation density, which may render a recipe for stress release in additively manufactured materials.
One‐Pot Hydrothermal Synthesis of Core–Shell MnS@MoS2 Heterojunction for Enhanced Microwave Absorption
Authors: Tian Xiaoyu , Wang Yueyue , Wang Jingjing , Guo Zhonglu , Hu Long , Tang Chengchun , Chen Guifeng , Fang Yi
Published: December 2022

As a typical 2D transition metal dichalcogenide (TMD), molybdenum disulfide (MoS2) has received widespread attention in the field of microwave absorption (MA). However, pure MoS2 still has disadvantages in achieving the target of excellent MA performance due to its weak ability in electromagnetic wave (EMW) energy attenuation, in addition to the complicated preparation process of MoS2‐based composites. It is highly significant to develop functionalized MoS2 with a low‐cost, high‐efficiency, and facile preparation process. Herein, a novel core–shell MnS@MoS2 composite with spherical flower‐like structure is developed by a one‐pot hydrothermal method. The morphological and performance characterization demonstrates the existence of numerous heterogeneous interfaces, which dramatically enhance the dielectric loss capability of the composites. By adjusting the ratio of Mo4+ and Mn2+, the minimum reflection loss (RLmin) of MnS@MoS2‐40 composite reaches −65.19 dB and the effective absorption bandwidth (EAB) reaches 6.72 GHz. At the same time, MnS@MoS2‐60 composite can achieve the RLmin value of −53.58 dB and an EAB of up to 6.16 GHz (from 11.44 to 17.6 GHz) at a thickness of only 1.78 mm. These outstanding performances are based on microwave absorbers formed by transition metal sulfide heterojunctions, pioneering the first combination of α‐MnS and MoS2 for MA applications.
Fabrication of Ti3C2Tx‐Based Superhydrophobic Composite Coating for Reinforcement Corrosion Resistance of AZ31B Mg Alloy
Authors: Yin Xingxing , Li Bingfeng , Xue Shuaiya , Mu Peng , Li Jian
Published: December 2022

Incorporating MXene nanomaterials in coating is an effective strategy to fabricate anticorrosive coatings with superior corrosion resistance, depending on its characteristic structure and nature. However, it may accelerate the corrosion rate of metal once forming galvanic corrosion by direct contact with the substrate due to its high conductivity and hydrophilicity. Herein, 1H,1H,2H,2H‐perfluorodecyltrichlorosilane (PFDTS) is used to functionalize Ti3C2Tx nanosheets to obtain superhydrophobic Ti3C2Tx hybrids, which greatly enhances the hydrophobicity of Ti3C2Tx nanosheets. Then, a new strategy is designed to construct superhydrophobic Ti3C2Tx/epoxy/cerium conversion (STECC) composite coating with sandwich‐like structure, which consists of bottom cerium conversion coating, intermediate epoxy coating, and top superhydrophobic Ti3C2Tx coating layer. The underlying cerium conversion layer and intermediate epoxy coating acted as the protective coating not only improve the corrosion protection ability of substrate but also isolate the top superhydrophobic Ti3C2Tx layer from direct contact with the substrate, which can eliminate direct contact between MXene and Mg alloy to further restrain the corrosion–promotion effect of Ti3C2Tx. The STECC with unique structure exhibits excellent water repellency, robust mechanical and chemical stability. Electrochemical experimental results demonstrate that the modified MXene nanosheets can remarkably improve the corrosion protection performance of STECC composite coating, and the impedance modulus of STECC coating reaches the value of approximately 7.49 × 106 Ω cm2 and increases four orders of magnitude compared with the Mg substrate. The composite coating studied here may offer valuable insights and inspiration toward developing MXene‐based coating for high‐performance anticorrosion.
3D Acoustofluidics via Sub‐Wavelength Micro‐Resonators
Authors: Harley William Sean , Kolesnik Kirill , Xu Mingxin , Heath Daniel Edward , Collins David John
Published: December 2022

Precise acoustic micromanipulation is emerging as an important tool in biomedical research, where acoustic forces have the advantage of being contact‐free, label‐free, and biocompatible. Conventional acoustofluidic approaches, however, produce device‐scale effects that limit the ability to locally target acoustic energies at the microscale. In this study, we demonstrate an approach to generate designed and highly local acoustic fields using 3D resonant mass‐spring microstructures, achieving local acoustic field gradients on the order of microns, orders of magnitude smaller than the fluid wavelength. In doing so, rapid and spatially defined controllable micromanipulation, including particle capture, transport, and patterning using arbitrarily arranged micro‐resonator arrays is demonstrated. This sub‐wavelength, 3D acoustofluidic approach results in highly localized and defined micromanipulation, with potential applications across sample preparation, cell analysis, and diagnostics.
2D MXenes for Fire Retardancy and Fire‐Warning Applications: Promises and Prospects
Authors: Liu Lei , Feng Jiabing , Xue Yijiao , Chevali Venkata , Zhang Yubai , Shi Yongqian , Tang Long‐Cheng , Song Pingan
Published: December 2022

Frequent fire disasters have caused massive impacts to the environment, human beings, and the economy. MXene has recently been intensively researched as potential flame retardants to provide passive fire protection for other materials via its physical barrier and catalyzing carbonization effects. In parallel, MXene has also demonstrated a great promise for creating early fire warning sensors, which is an emerging field that has the potential to provide active fire response through its thermoelectric effect. This makes it possible to integrate passive fire retardancy and active fire warning into one MXene‐based fire protection system on demand. However, fulfilling these promises needs more research. Herein, an overview of passive flame‐retardant materials and next‐generation smart fire warning materials/sensors based on MXene and its derivatives is provided. This study reviews their conceptual design, characterization, modification principles, performances, applications, and mechanisms. A discussion of the challenges that need to be solved for their future practical applications and opportunities is also presented.
Room‐Temperature Gate‐Tunable Nonreciprocal Charge Transport in Lattice‐Matched InSb/CdTe Heterostructures
Authors: Li Lun , Wu Yuyang , Liu Xiaoyang , Liu Jiuming , Ruan Hanzhi , Zhi Zhenghang , Zhang Yong , Huang Puyang , Ji Yuchen , Tang Chenjia , Yang Yumeng , Che Renchao , Kou Xufeng
Published: December 2022

Symmetry manipulation can be used to effectively tailor the physical order in solid‐state systems. With the breaking of both the inversion and time‐reversal symmetries, nonreciprocal magneto‐transport may arise in nonmagnetic systems to enrich spin–orbit effects. Here, the observation of unidirectional magnetoresistance (UMR) in lattice‐matched InSb/CdTe films is investigated up to room temperature. Benefiting from the strong built‐in electric field of 0.13 V nm−1 in the heterojunction region, the resulting Rashba‐type spin–orbit coupling and quantum confinement result in a distinct sinusoidal UMR signal with a nonreciprocal coefficient that is 1–2 orders of magnitude larger than most non‐centrosymmetric materials at 298 K. Moreover, this heterostructure configuration enables highly efficient gate tuning of the rectification response, wherein the UMR amplitude is enhanced by 40%. The results of this study advocate the use of narrow‐bandgap semiconductor‐based hybrid systems with robust spin textures as suitable platforms for the pursuit of controllable chiral spin–orbit applications.
X‐ray‐Guided In Situ Genetic Engineering of Macrophages for Sustained Cancer Immunotherapy
Authors: Zhao Caiyan , Cheng Yaya , Huang Pei , Wang Changrong , Wang Weipeng , Wang Mengjiao , Shan Wenbo , Deng Hongzhang
Published: December 2022

Effective repolarization of macrophages has emerged as a promising approach for anticancer therapy. However, there are very few studies on the effect of reprogramming macrophages from M2 phenotype to M1 phenotype without reconversion while maintaining an activated M1 phenotype. Moreover, these immunomodulatory methods have serious drawbacks due to the activation of normal monocytic cells. Therefore, it remains a challenge to selectively reprogram tumor‐associated macrophages (TAMs) without systemic toxicities. Here, X‐ray‐guided and triggered remote control of a CRISPR/Cas9 genome editing system (X‐CC9) that exclusively activates therapeutic agents at tumor sites is established. Under X‐ray irradiation, X‐CC9 selectively enhances M2‐to‐M1 repolarization within the tumor microenvironment, and significantly improves antitumor efficacy with robust immune responses in two animal models. This strategy provides an ideal method for improving the safety of macrophage polarization and may constitute a promising immunotherapy strategy.
Highly Stretchable and Biocompatible Wrinkled Nanoclay‐Composite Hydrogel With Enhanced Sensing Capability for Precise Detection of Myocardial Infarction
Authors: Zhang Jie , Shen Si , Lin Rurong , Huang Jianxing , Pu Chunyi , Chen Pinger , Duan Qixiang , You Xintong , Xu Chengzhong , Yan Bing , Gao Xinrui , Shen Ziqi , Cai Liu , Qiu Xiaozhong , Hou Honghao
Published: December 2022

It is challenging to balance high biocompability with good mechanical–electrical sensing performance, especially when triggering inflammatory stress response after in vivo implantation. Herein, a bioinspired wrinkle‐reinforced adaptive nanoclay‐interlocked soft strain‐sensor based on a highly stretchable and elastic ionic‐conductive hydrogel is reported. This novel nanoclay‐composite hydrogel exhibits excellent tensile properties and high sensing capacity with steady and reliable sensing performance due to the structural–mechanical–electrical integrity of the nanoclay crosslinked and nano‐reinforced interpenetrating network. The incorporation of amphiphilic ions provides the hydrogel with significant protein resistance, reducing its non‐specific adsorption to proteins upon implantation, improving its biosafety as an implanted device, and maintaining the authenticity of the sensing results. Based on the revealed sensing enhanced mechanism based on hierarchical ordered structures as a proof‐of‐concept application, this hydrogel sensor is demonstrated to be able to accurately localize the region where myocardial infarction occurs and may become a novel strategy for real‐time monitoring of pathological changes in heart disease.