bluuebunny/crossref_metadata_2025 huggingface dataset:
Very-high-frequency normal mode modeling
Authors: Werby Michael F.
Published: July 2002

The relevant quantity that determines the complexity of modeling via the normal mode method is the number of modes required in the problem. That is only partly determined by the frequency. Other factors that enter the problem are the water column depth and the mean sound speed in the water column and the bottom. Crudely the number of modes is proportional to the product of the water column depth and the frequency times what we call the hardness parameter and as well as the inverse of the mean speed of sound in the water column. The hardness parameter is equal to the square root of the factor of 1 minus the square of the ratio of the mean sound speed in the water column to that in the bottom. We determine the actual equation for the number of modes in a refractive wave guide with a layered bottom. We illustrate the modal spectrum for the general problem. Based on that we show some tricks useful to model high-frequency problems on the order of several thousands of modes.
Determining velocity profile characteristics from pulse signals in a wave-guide
Authors: Werby Michael F. , Uberall Herbert
Published: July 2002

We use techniques similar to that of vertical seismic profiling to determine the velocity profile of a waveguide by examining contour plots from the emergence of pulse signals. The concept of acoustic adumbrations to determine features of the wave-guide channeling effect is discussed. It may be seen that the contour plots yield and outline adumbration that ‘‘shadows’’ the features of the profile.
Vocal warm-ups: What do they accomplish?
Authors: Titze Ingo R.
Published: July 2002

In the past, vocal warm-ups have been little more than a few scales and arpeggios on a few selected vowels, whether for choir or for solo singing. In recent years, however, a greater understanding of the mechanism of the human voice, combined with a greater understanding of exercise physiology, has led to entire systems of carefully designed sequences of exercises. Specific muscles are targeted, even specific portions of the vocal fold. Of principal interest is the way in which the vocal tract is engaged, and ultimately disengaged, in providing acoustic loads for the vocal oscillator. A system of warm-up exercises will be presented here that have become the backbone of vocology, the science and practice of voice habilitation.
Video investigation of the effects of gravity on single-bubble sonoluminescence
Authors: Dzikowicz Ben , Thiessen David B. , Marston Philip L.
Published: July 2002

Using NASA’s KC-135 aircraft flying parabolic trajectories, we can observe SBSL as the effective gravity changes from near 0 g to about 1.8 g. A spherical resonator operated at 32.5 kHz is suspended in a constant ambient pressure chamber. Then, a photomultiplier measures light emission while a strobed CCD camera obtains images of the bubble collapse. In normal gravity, buoyancy displaces the bubble from the velocity node of the sound field so that water is flowing past the bubble at the time of collapse. Other gravitational effects include the variation in ambient pressure. During intervals of negligible drift of the SBSL intensity, there can be a rapid intensity rise of between 4% and 20% as the effective gravity decreases. The CCD images are then used to calculate the bubble radius. These measurements were fit to the Rayleigh–Plesset equation to infer the size and pressure conditions by assuming spherical bubble oscillations. These conditions were found to be similar to those reported by other groups for measurements in normal gravity. There are also indications that changes in the effective gravity are accompanied by small changes in the maximum bubble radius. [Work supported by NASA.]
Matched-field source localization using data-derived modes
Authors: Hursky Paul , Hodgkiss W. S. , Kuperman W. A.
Published: July 2002

Acoustic modes can be derived from the cross-spectral density matrix of a vertical line array in an ocean wave guide, when spatially distributed ambient noise or a moving source causes the modes at the array to be uncorrelated. This typically produces modes that are noisy and incomplete (only some modes are recovered, at some frequencies, and only at depths spanned by the array). Furthermore, without wave numbers, only incoherent localization algorithms are possible, providing less gain than coherent MFP using wave numbers. It will be shown how to overcome these problems, assuming the sound speed profile has been measured in the water column but assuming no a priori knowledge of bottom properties. A data-dependent shooting method is presented which extrapolates the data-derived modes to the entire water column and estimates both the wave numbers and bottom properties. Having bottom parameters enables modes to be calculated at all frequencies, rather than being limited to frequencies of sources of opportunity. The MFP results will be presented from the SWellEX-96 experiment using data-derived modes and compared to MFP based on modes from a normal mode model.
Localization method based on the higher-order statistics
Authors: Bourennane Salah
Published: July 2002

In the context of the narrow-band or wideband array processing problem, in this paper we develop a robust algorithm to improve the accuracy of the estimation of the direction of arrival of the sources. It is well known that when the noise covariance matrix is unknown, these estimates may be grossly inaccurate. Using both the higher-order statistics for suppression of the additive Gaussian noise, the transformation matrices for estimating the coherent signal subspace, and the high-resolution algorithm a robust and fast algorithm for the source parameters estimation in the presence of noise with an unknown cross-spectral matrix is developed. We shall show that the performance of bearing estimation algorithms improves substantially when our algorithm is used. Several simulation results are presented with different noise spectral matrices.
Application of matched filtering for environmental compensation
Authors: Gaumond Charles F.
Published: July 2002

The problem of improving the performance of broadband sonar through the use of modeling is posed. An approach to this problem is presented in terms of matched filtering. Specific filtering equations are derived from a coherent sonar equation as a signal model and a broadband sound propagation model. The approach assumes a statistical distribution of target positions with consequently stochastic response that is then shown to be describable with a signal space. The basis of the signal space is derivable from a broadband propagation model. The resultant signal space is used with a separable-kernel detector. The significant improvement of detection over conventional matched filtering is demonstrated for an impulsive signal in a simple, dispersive channel with additive, Gaussian, white noise. Furthermore, this signal-processing methodology has the potential for depth discrimination if the channel response is significantly different in different depth intervals. This difference is expressed as the overlap of signal spaces. The relationship of the overlap to depth discrimination is shown. [Work supported by the Office of Naval Research.]
A Bayesian approach to model-based source localization using arrival time information
Authors: Michalopoulou Zoi-Heleni , Ma Xiaoqun
Published: July 2002

In this work, the potential of a model-based time delay estimation approach for source localization in the ocean is explored. Source localization in an underwater waveguide is typically approached with full-field matching techniques such as matched-field processing. The proposed method is similar to matched-field processing in that it matches measured arrival times to replica arrival times; it is, however, more efficient because it does not rely on exhaustive replica computations. The method links identified arrival times to source location parameters through an approximate linear model. Using a Bayesian approach and through the maximization of the a posteriori probability density function of the source location parameters, the coordinates that satisfy best the linear model are identified yielding the source location estimates. The method is tested with synthetic data and is shown to be accurate and fast. In addition to source localization in a known medium, the method is extended to uncertain media cases; specifically, the case of unknown water column depth is investigated. The model-based time delay method is applied successfully in that case both for source localization and ocean depth estimation.
Time and timing: Age-related differences in auditory, speech, language, and cognitive processing
Authors: Pichora-Fuller M. Kathleen
Published: July 2002

Older adults have difficulty understanding language spoken in noisy conditions or at fast rates, even though they may have little difficulty with slow speech in quiet. Reduced audibility in the spectral domain cannot fully account for their difficulties. Differences in temporal processing may provide new explanations. Temporal processing includes synchrony coding (phase-locking), gap and duration coding (onset and offset detection), and coding of rhythmic patterns (envelope patterns). Particular speech cues rely on particular types of auditory temporal processing: voice cues arising from vocal-fold vibration rely on synchrony coding; some segmental contrasts rely on gap and duration coding; suprasegmental cues associated with syllabic rhythms rely on coding of higher-level patterns. The relationship between psychoacoustic and speech-perception measures will be considered at each of these levels of temporal processing. Evidence of age-related differences has been demonstrated in studies employing jittered and speeded speech, and speech with reduced stop-consonant gaps. While researchers have argued that perceptual and cognitive declines both affect aging listeners, apparent age-related differences in cognitive performance seem to be secondary to perceptual differences. Both time and timing seem to be affected, with aging auditory systems being slower and more asynchronous.
Anticipatory coarticulation in the speech of adults and children: A perceptual study
Authors: Bharadwaj Sneha V. , Katz William F.
Published: July 2002

Two competing theories attempt to explain anticipatory coarticulation in the speech of adults and children: One suggests more extensive coarticulation in children’s speech than in that of adults, while the other suggests more extensive coarticulation in adult speech [see S. Nittrouer and D. Whalen, J. Acoust. Soc. Am. 86, 1266–1276 (1989) for discussion]. To address this issue, a perceptual experiment was conducted in which adult listeners identified vowel information from gated CV syllables. The syllables /si/, /su/, /∫i/, and /∫u/ produced by children (5 and 7 years old) and adults were gated into four segments of varying lengths (1/2 fricative, 3/4 fricative, full fricative, and fricative +1/2 vowel). The stimuli were presented to ten adult listeners in randomized order (experiment 1) and to another ten listeners, blocked by individual talkers (experiment 2). Syllable identification for key fricative gates was 6% better in blocked compared to random presentation. Both experiments revealed a trend of listeners detecting more extensive coarticulation in children’s productions than in those of adults; however, this pattern resulted from heightened responses to a single 7-year-old talker. Results suggest children coarticulate with greater variability than adults, but not necessarily with a greater temporal extent.
Lip and throat configuration in flute playing
Authors: Hwang Joon-Hee Beth , Thorpe William
Published: July 2002

This study reports on simultaneous measurements of lip aperture and glottal aperture during varied performance tasks by each of a group of six expert flute players. Lip aperture was recorded using a video camera, and glottal aperture with a nasendoscope. Video images were selected from stable portions of the recording and digitized, and measurements of vocal fold and lip opening were made from the display. The results showed that there was a general trend of increasing lip aperture with increase in loudness and decrease in lip aperture with increasing pitch. Similarly, glottal aperture increased with increase in loudness and decreased with increase in pitch. The ratio of glottal to lip aperture area generally decreased with increase in pitch, the glottal aperture always being greater than the lip aperture. Although the results of this study generally agree with those of previous studies [J. W. Coltman, J. Acoust. Soc. Am. 40, 99–107 (1966), 44, 983–992 (1968), N. H. Fletcher, ibid. 57, 233–237 (1975), S. Mukai, J. Otolaryngol. Jpn. 92, 260–270 (1989)], players showed considerable individual variation. This suggests that various compromises in technique are possible among expert players.
Analytical regularization based analysis of a spherical reflector symmetrically illuminated by an acoustic beam
Authors: Vinogradov Sergey S. , Vinogradova Elena D. , Nosich Alexander I. , Altintaş Ayhan
Published: July 2002

A mathematically accurate and numerically efficient method of analysis of a spherical reflector, fed by a scalar beam produced by a complex source-point feed, is presented. Two cases, soft and hard reflector surface, are considered. In each case the solution of the full-wave integral equation is reduced to dual series equations and then further to a regularized infinite-matrix equation. The latter procedure is based on the analytical inversion of the static part of the problem. Sample numerical results for 50-λ reflectors demonstrate features that escape a high-frequency asymptotic analysis.
Results of an independent analysis of the inverse beamformer for use in the advanced processor build process
Authors: Carter G. Clifford
Published: July 2002

The inverse beamformer (IBF) is a signal-processing algorithm developed for underwater applications. The advanced processor build (APB) is a recently developed process for sonar test and evaluation. This correspondence describes both and summarizes the results of an independent “data-driven” test and evaluation of the IBF by using the APB. Discussion includes the underlying reasons for gains observed over conventional systems and applicability to uncluttered acoustical environments.
Synthesis and modification of the whistles of the bottlenose dolphin,Tursiops truncatus
Authors: Buck John R. , Morgenbesser Hugh B. , Tyack Peter L.
Published: July 2002

A signal-processing algorithm was developed to analyze harmonic frequency-modulated sounds, to modify the parameters of the analyzed signal, and to synthesize a new analytically specified signal that resembles the original signal in specified features. This algorithm was used with dolphin whistles, a frequency-modulated harmonic signal that has typically been described in terms of its contour, or pattern of modulation of the fundamental frequency. In order to test whether other features may also be salient to dolphins, the whistle analysis calculates the energies at the harmonics as well as the fundamental frequency of the whistle. The modification part of the algorithm can set all of these energies to a constant, can shift the whistle frequency, and can expand or compress the time base or the frequency of the whistle. The synthesis part of the algorithm then synthesizes a waveform based upon the energies and frequencies of the fundamental and first two harmonics. These synthetic whistles will be useful for evaluating what acoustic features dolphins use in discriminating different whistles.
A rapid technique to determine the internal area function of finite-length ducts using maximum length sequence analysis
Authors: de Salis M. H. F. , Oldham D. J.
Published: July 2002

This paper describes a rapid technique for reconstruction of the internal area function of a duct using blockage-induced eigenvalue shifts determined from eigenfrequencies measured under two sets of duct termination boundary conditions. A single broad band maximum length sequence (MLS) measurement of short duration is utilized to obtain the transfer function of the duct, which in turn can be utilized to determine its eigenvalue shifts and subsequently its internal area function using an inverse perturbation technique. The reconstruction results display the same order of accuracy as those obtained previously using swept sine measurements of extended duration. An expression for the determination of the area function is presented utilizing resonant frequency information alone, thus rendering duct length determination unnecessary. A computational routine further simplifies the process such that the accuracy of the technique could be ascertained for a range of configurations including longer ducts and ducts that initially have nonuniform internal cross section over their length. Development of a relationship between obstacle length and wavelength of the lowest eigenfrequency required for successful reconstruction is also described. This is an important result for longer ducts where measurement of lower eigenfrequencies may present problems using standard measurement equipment.
Tomography of dispersive media
Authors: Ernst Fabian E. , Herman Gérard C.
Published: July 2002

When waves propagate through layered structures, the phase velocity is frequency dependent (dispersive). If one wants to reconstruct the velocity variations in this medium, conventional traveltime-based tomographic methods cannot be used, since each frequency component has a different traveltime. A tomographic method is presented for reconstructing the phase velocity of guided waves in laterally varying media. The dispersive character of guided waves is explicitly accounted for by using a phase-based error criterium instead of “picked” traveltimes. Phase velocity and source waveform can be reconstructed to within a few percent, and the algorithm is shown to be robust in the presence of interference noise. When applied to seismic field data, the reconstructed phase velocity field correlates well with the topography of the area.
Variation of measured sound speeds in gaseous and liquid air with temperature and pressure
Authors: Wong George S. K. , Wu Lixue , Leung Kam
Published: July 2002

Based on sound speeds in gaseous and liquid air measured by Younglove and Frederick [Int. J. Thermophys. 13(6), 1033–1041 (1992)], empirical equations for the computation of sound speeds in the above media at relatively smaller temperature and pressure ranges were derived. For gaseous air, over a temperature range from 200 to 300 K and pressure from 0.614 to 10.292 MPa, the maximum deviation between the measured sound speeds and those computed with the empirical equation is 56 ppm. For liquid air, over the ranges from 90 to 110 K for temperature and from 0.763 to 13.823 MPa for pressure, the corresponding deviation is 173 ppm.
On the Mechanical Behavior of Elastic Animal Tissue
Authors: Blatz Paul J. , Mae Chu Billie , Wayland Harold
Published: July 2002

In this paper there is introduced a strain energy function which describes a class of materials that includes elastic animal tissue as well as other highly distensible materials. The functional form of this representation is general enough to suggest other forms that may encompass additional classes of material. The theoretical stress-strain curves are shown to correlate well with experimental data obtained upon loading (as distinguished from unloading) different animal tissues such as frog’s striated muscle, human papillary muscle, and cat’s and rabbit’s mesentery, as well as synthetic materials such as latex rubber. There is also developed a thinness theory which can be used to calculate the deformation field in the case of applied plane stress for the more complicated geometry of a wedge-shaped (arcuate) specimen. This thinness theory has been applied to a fan-shaped specimen with tangential and radial loading.
Treatment of Multisystem Inflammatory Syndrome in Children: Understanding Differences in Results of Comparative Effectiveness Studies
Authors: Melgar Michael , Seaby Eleanor G. , McArdle Andrew J. , Young Cameron C. , Campbell Angela P. , Murray Nancy L. , Patel Manish M. , Levin Michael , Randolph Adrienne G. , Son Mary Beth F. ,   BATS Consortium and the Overcoming COVID‐19 Investigators
Published: June 2022

Objective

Two cohort studies in patients with multisystem inflammatory syndrome in children (MIS‐C) demonstrated contrasting results regarding the benefit of initial immunomodulatory treatment with intravenous immunoglobulin (IVIG) alone versus IVIG and glucocorticoids. We sought to determine whether application of different MIS‐C definitions and differing disease severity between cohorts underlay discrepant results.

Methods

The Overcoming COVID‐19 Public Health Surveillance Registry (OC‐19) included patients meeting the US Centers for Disease Control and Prevention (CDC) MIS‐C definition, whereas the Best Available Treatment Study (BATS) applied the World Health Organization (WHO) definition. We applied the WHO definition to the OC‐19 cohort and the CDC definition to the BATS cohort and determined the proportion that did not meet the alternate definition. We compared illness severity indicators between cohorts.

Results

Of 349 OC‐19 patients, 9.5% did not meet the WHO definition. Of 350 BATS patients, 10.3% did not meet the CDC definition. Most organ system involvement was similar between the cohorts, but more OC‐19 patients had WHO‐defined cardiac involvement (87.1% vs 79.4%, P = 0.008). OC‐19 patients were more often admitted to intensive care (61.0% vs 44.8%, P < 0.001) and more often received vasopressors or inotropes (39.5% vs 22.9%, P < 0.001) before immunomodulatory treatment.

Conclusion

Greater illness severity and cardiovascular involvement in the OC‐19 cohort compared with the BATS cohort, and not use of different MIS‐C case definitions, may have contributed to differing study conclusions about optimal initial treatment for MIS‐C. Disease severity should be considered in future MIS‐C study designs and treatment recommendations to identify patients who would benefit from aggressive immunomodulatory treatment.
A Dual‐Action Molecule Suppresses S. aureus Infection as an Inhibitor Targeting Hla Pore Formation and TLR2 Signaling
Authors: Wang Tingting , Jiang Fan , Su Jianqing , Chu Xiuling , Cao Yongguo , Lv Hongfa , Deng Xuming , Wang Jianfeng
Published: June 2022

Antibiotic resistance is the greatest challenge for the treatment of Staphylococcus aureus (S. aureus) infection under the global antibiotic resistance crisis. With the bottleneck period of the development of new antibiotics, novel alternative agents are urgently in need. In this study, the small molecule amentoflavone is identified as a dual‐action inhibitor of Hla, a pore‐forming virulence determinant particularly important for S. aureus pathogenicity and Toll‐like receptor 2 (TLR2) signaling, which triggers inflammation response upon recognizing pathogen‐associated molecular patterns. Amentoflavone treatment conferred effective protection against S. aureus pneumonia through this dual‐action mechanism. Mechanically, amentoflavone effectively inhibited Hla pore formation, thereby reducing Hla‐mediated cytotoxicity and tissue damage; at the same time, amentoflavone suppressed TLR2‐mediated inflammatory response by blocking the interaction between TLR2 and its adapter myeloid differentiation primary response gene 88 (MyD88). Surprisingly, TLR2 signaling induced by synthetic bacterial TLR2 agonists and other heat‐killed gram‐positive bacteria is also blocked by amentoflavone. In summary, these results presented amentoflavone as a potential antibiotic alternative that curbed S. aureus infection by simultaneously suppressing host‐damaging virulence determinants derived from bacteria and the detrimental effect of excessive inflammation derived from the host rather than bacteria viability.
Conjugated Polymers for Microwave Applications: Untethered Sensing Platforms and Multifunctional Devices
Authors: Tan Siew Ting Melissa , Giovannitti Alexander , Marks Adam , Moser Maximilian , Quill Tyler J. , McCulloch Iain , Salleo Alberto , Bonacchini Giorgio E.
Published: June 2022

In the past two decades, organic electronic materials have enabled and accelerated a large and diverse set of technologies, from energy‐harvesting devices and electromechanical actuators, to flexible and printed (opto)electronic circuitry. Among organic (semi)conductors, organic mixed ion–electronic conductors (OMIECs) are now at the center of renewed interest in organic electronics, as they are key drivers of recent developments in the fields of bioelectronics, energy storage, and neuromorphic computing. However, due to the relatively slow switching dynamics of organic electronics, their application in microwave technology, until recently, has been overlooked. Nonetheless, other unique properties of OMIECs, such as their substantial electrochemical tunability, charge‐modulation range, and processability, make this field of use ripe with opportunities. In this work, the use of a series of solution‐processed intrinsic OMIECs is demonstrated to actively tune the properties of metamaterial‐inspired microwave devices, including an untethered bioelectrochemical sensing platform that requires no external power, and a tunable resonating structure with independent amplitude‐ and frequency‐modulation. These devices showcase the considerable potential of OMIEC‐based metadevices in autonomous bioelectronics and reconfigurable microwave optics.
Binary Cooperative Complementary Membranes: A Perspective
Authors: Wang Bo , Wang Tie
Published: June 2022

Binary cooperative complementary principle (BCCP) refers to two opposite but cooperative and complementary species or states. Currently, a variety of high‐performance membranes fabricated using membrane materials with BCCP, are known as binary cooperative complementary membranes (BCCMs). Three types of BCCMs are discussed including hybrid membranes with the BCCP of channel‐in‐matrix and channel‐on‐channel, amphiphilic membranes with the BCCP of hydrophobicity and hydrophilicity, ion exchange membranes with the BCCP of cation and anion. Concrete examples of BCCMs are demonstrated followed by discussing the BCCP effects. The introduction of BCCP in membrane materials presents a new direction to analyze the impact factors about membrane structure and membrane performance. Using membrane materials with rational utilization of the BCCP is believed to be a new trend in the fabrication of high‐performance membranes in the wide range of application fields. Finally, the authors will put forward the significance of BCCMs and present an outlook for the future development of this topic.
Hypertension and Alzheimer's disease pathology at autopsy: A systematic review
Authors: Abdulrahman Herrer , van Dalen Jan Willem , den Brok Melina , Latimer Caitlin S. , Larson Eric B. , Richard Edo
Published: June 2022

Hypertension is an important risk factor for Alzheimer's disease (AD) and all‐cause dementia. The mechanisms underlying this association are unclear. Hypertension may be associated with AD neuropathological changes (ADNC), but reports are sparse and inconsistent. This systematic review included 15 autopsy studies (n = 5879) from observational cohorts. Studies were highly heterogeneous regarding populations, follow‐up duration, hypertension operationalization, neuropathological methods, and statistical analyses. Hypertension seems associated with higher plaque and tangle burden, but results are inconsistent. Four studies (n = 3993/5879; 68%), reported clear associations between hypertension and ADNC. Another four suggested that antihypertensive medication may protect against ADNC. Larger studies with longer follow‐up reported the strongest relationships. Our findings suggest a positive association between hypertension and ADNC, but effects may be modest, and possibly attenuate with higher hypertension age and antihypertensive medication use. Investigating interactions among plaques, tangles, cerebrovascular pathology, and dementia may be key in better understanding hypertension's role in dementia development.
The Perioperative Steering Committee as an Accountable Infrastructure to Enable and Sustain Change
Authors: Voight Patrick , Fuller Mary , McKean Kiren
Published: June 2022

Leaders in perioperative and interventional procedure areas need to be able to initiate and sustain change to improve operational processes in their departments or service lines. Although available literature discusses change in health care organizations, there is a lack of published articles on the implementation and sustainment of change. This article provides a review of supporting literature on change management and an infrastructure model that we have successfully implemented to sustain change. An organizational case study focused on creating sustained improvements for first procedure on‐time starts and turnover times details the process of creating the accountability system for actualizing the performance targets in a perioperative environment. The case study examines the existing process and initial challenges with creating sustainable and quantifiable outcomes, describes the process of implementing the infrastructure discussed in the article, and evaluates the results. Perioperative leaders can use the information to improve processes in their work environments.
Epoxy resin/hollow glass microspheres composite materials with low dielectric constant and excellent mechanical performance
Authors: Zhang Xiaolin , Liu Man , Chen Yu , He Jiacheng , Wang Xuelin , Xie Jian , Li Ziwei , Chen Zhimin , Fu Yuheng , Xiong Chuanxi , Wang Shan
Published: June 2022

The materials with low dielectric constant and low dielectric loss are vital for high integration degree of the circuit board. Although many polymers like epoxy resin exhibit excellent comprehensive performance, their dielectric constant is unable to satisfy high electronic packaging application. In this work, we present a simple grafting strategy via reaction between the hollow glass microsphere and polyhedral oligomeric silsesquioxane followed by blending epoxy resin to fabricate epoxy resin hollow glass microspheres composite materials. The superior heat resistance of hollow glass microspheres (HGM) can improve the thermal performance of composites. Due to the addition of Ge‐POSS, P‐HGM exhibited a good interfacial compatibility with epoxy resin matrix and forms an interfacial adhesion region. With the P‐HGM loading of 20 wt%, the fabricated composite materials exhibited the low dielectric constant of 2.59 and low dielectric loss of 0.0145. At the same time, the tensile strength, impact strength and flexural strength were 42.15 MPa, 24.33 kJ/m2 and 90.82 MPa, respectively, which demonstrated that the epoxy resin hollow glass microspheres composite materials processed superb mechanical behavior. It suggests that this method is a promising potential for fabricating low dielectric composite materials.
Maternal cigarette smoking and alcohol consumption and congenital diaphragmatic hernia
Authors: Finn Julia , Suhl Jonathan , Kancherla Vijaya , Conway Kristin M. , Oleson Jacob , Sidhu Alpa , Nestoridi Eirini , Fisher Sarah C. , Rasmussen Sonja A. , Yang Wei , Romitti Paul A. ,   the National Birth Defects Prevention Study
Published: June 2022

Background

Congenital diaphragmatic hernia (CDH) occurs when abnormal diaphragm development allows herniation of abdominal organs into the thoracic cavity. Its etiopathogenesis is not well understood, but cigarette smoking and alcohol exposure may impact diaphragm development. Using data from a large, population‐based case–control study, we examined associations between maternal cigarette smoking and alcohol consumption and CDH in offspring.

Methods

We analyzed maternal interview reports of cigarette smoking and alcohol consumption during early pregnancy for 831 children with CDH and 11,416 children without birth defects with estimated dates of delivery during 1997–2011. Generalized linear mixed effects models with a random intercept for study site were used to estimate associations between measures of exposure to smoking (any, type, frequency, duration) and alcohol (any, quantity, frequency, variability, type) for all CDH combined and selected subtypes (Bochdalek and Morgagni).

Results

Mothers of 280 (34.0%) case and 3,451 (30.3%) control children reported early pregnancy exposure to cigarette smoking. Adjusted odds ratios for all CDH were increased for any (1.3; 95% confidence interval 1.1–1.5), active (1.3, 1.0–1.7), and passive (1.4, 1.1–1.7) smoking. Early pregnancy alcohol consumption was reported by mothers of 286 (34.9%) case and 4,200 (37.0%) control children; odds were near the null for any consumption (0.9, 0.8–1.1) and consumption with (0.9, 0.7, 1.1) or without (0.9, 0.8, 1.1) binging. Estimates for smoking and alcohol tended to be higher for Bochdalek CDH and Morgagni CDH than those for all CDH.

Conclusions

Findings suggest that maternal early pregnancy exposure to cigarette smoking, but less so to alcohol consumption, contributes to CDH. These findings need to be replicated in additional large studies that use systematic case ascertainment and classification, detailed exposure assessment, and examine subtype‐specific associations.
Unraveling docking and initiation of mRNA export through the nuclear pore complex
Authors: Tingey Mark , Yang Weidong
Published: June 2022

The nuclear export of mRNA through the nuclear pore complex (NPC) is a process required for the healthy functioning of human cells, making it a critical area of research. However, the geometries of mRNA and the NPC are well below the diffraction limit of light microscopy, thereby presenting significant challenges in evaluating the discrete interactions and dynamics involved in mRNA nuclear export through the native NPC. Recent advances in biotechnology and single‐molecule super‐resolution light microscopy have enabled researchers to gain granular insight into the specific contributions made by discrete nucleoporins in the nuclear basket of the NPC to the export of mRNA. Specifically, by expanding upon the docking step facilitated by the protein TPR in the nuclear basket as well as identifying NUP153 as being the primary nuclear basket protein initiating export through the central channel of the NPC.
Early versus late discharge after transcatheter aortic valve replacement and readmissions for permanent pacemaker implantation
Authors: Elzanaty Ahmed M. , Maraey Ahmed , Elbadawi Ayman , Khalil Mahmoud , Hashim Ahmed , Vyas Rohit , Moustafa Abdelmoneim , Ramanthan Periakaruppan Kasi , Mentias Amgad , Abbott J. Dawn , Aronow Herbert D. , Kapadia Samir , Saad Marwan
Published: June 2022

Objective

To examine the rate of readmission for permanent pacemaker (PPM) implantation with early versus late discharge after transcatheter aortic valve replacement (TAVR).

Background

There is a current trend toward early discharge after TAVR. However, paucity of data exists on the impact of such practice on readmissions for PPM implantation.

Methods

The Nationwide Readmission Database 2016–2018 was queried for all hospitalizations where patients underwent TAVR. Hospitalizations were stratified into early (Days 0 and 1) versus late (≥Day 2) discharge groups. Observations in which PPM was required in the index admission were excluded. Multivariable regression analyses involving patient‐ and hospital‐related variables were utilized. The primary outcome was 90‐day readmission for PPM implantation.

Results

The final analysis included 68,482 TAVR hospitalizations, 20,261 (29.6%) with early versus 48,221 (70.4%) with late discharge. Early discharge after TAVR increased over the study period (16.2% in 2016 vs. 37.9% in 2018, Ptrend < 0.01). Nevertheless, 90‐day readmission for PPM implantation remained stable (1.8% in 2016 vs. 2.0% in 2018, Ptrend = 0.32). The 90‐day readmission rate for PPM implantation (2.0% vs. 1.8%; adjusted odds ratio: 1.15; 95% confidence interval: 0.95–1.39; p = 0.15) and median time‐to‐readmission (5 days [interquartile range, IQR 3–9] vs. 5 days [IQR 3–14], p = 0.92) were similar with early versus late discharge. Similar rates were observed regardless of whether readmission was elective versus not. Early discharge was associated with lower hospitalization cost ($39,990 ± $13,681 vs. $46,750 ± $18,218, p < 0.01) compared with late discharge.

Conclusion

In patients who did not require PPM during the index TAVR hospitalization, the rate of readmission for PPM implantation was similar with early versus late discharge.
Percutaneous closure of patent foramen ovale for treatment of hypoxemia: A case series and physiology review
Authors: Robl Jared , Vutthikraivit Wasawat , Horwitz Phillip , Panaich Sidakpal
Published: June 2022

Intracardiac right‐to‐left shunt (RTLS) mediated hypoxemia is a rare complication of patent foramen ovale (PFO). The process may be potentiated by reversal of the usual trans‐atrial pressure gradient, or from alteration of intracardiac geometry such that venous flow is preferentially directed toward the PFO. We describe a series of four patients who presented with hypoxemia, detailing the diagnostic evaluation which led to the ascertainment of intracardiac RTLS across PFO as the culprit pathology. All underwent successful percutaneous closure with rapid resolution of hypoxemia. Particular attention is given to the underlying anatomic and physiologic derangements facilitating the intracardiac RTLS.
Development of transient trapping micellar electrokinetic chromatography coupled with mass spectrometry for steroids analysis
Authors: Manmana Yanawut , Liu Chenchen , Koino Hiroshi , Sueyoshi Kenji , Kitagawa Fumihiko , Kubo Takuya , Otsuka Koji
Published: June 2022

An on‐line sample preconcentration technique based on transient trapping (tr‐trapping) in micellar electrokinetic chromatography (MEKC) was applied for steroid detection with UV (tr‐trapping‐UV) and electrospray ionization mass spectrometry detection (tr‐trapping‐ESI‐MS). ESI‐MS was used to improve the sensitivity in MEKC. The MEKC separation was carried out using volatile ammonium formate as a background solution to facilitate the coupling with ESI‐MS. The partial introduction of a sodium dodecyl sulfate (SDS) micellar solution before the introduction of a sample solution to the capillary provided the effective preconcentration of analytes. At the same time, the SDS micelle would not enter the ESI‐MS system, so its interference in ESI‐MS detection was suppressed under the optimal condition, then five steroids can be separated by the developed method. In tr‐trapping‐ESI‐MS, an acidic condition of pH 3.5 was employed to suppress the electroosmotic flow, which can avoid micellar solution migrating to the MS instrument. The developed method showed that the micellar solution requires a twofold slower time than the sample to migrate along the column, which can prohibit the cause of the problem with the MS instrument and interference signal of SDS in the steroid's detection. The tr‐trapping‐ESI‐MS protocol showed up to 540‐fold enhancements of the peak intensity and 50‐fold improvement of the limit of detection compared with capillary zone electrophoresis using androsterone as a model sample.
Fe‐Incorporated Ni3S4/NiS2Nanocomposite as an Efficient Electrocatalyst for Alkaline Water Oxidation
Authors: Tudu Gouri , Ghosh Sourav , Inta Harish Reddy , Koppisetti Heramba V. S. R. M. , Ganguli Sagar , Mahato Ashok Kumar , Mahalingam Venkataramanan
Published: June 2022

We report the development of iron‐incorporated nickel sulfide (Fe−Ni3S4/NiS2) nanocomposite through sulfurization of iron incorporated nickel hydroxide precursor by using simple solvothermal method. The formation of Ni3S4/NiS2mixed‐phase material was confirmed by PXRD analysis and the presence of multiple oxidation states of Ni (II and III) and incorporated Fe (III) was revealed by XPS studies. The electrochemical studies demonstrated that Fe−Ni3S4/NiS2electrocatalyst has a high catalytic activity towards alkaline OER, as it requires only 280 mV overpotential to achieve the benchmark current density of 10 mA/cm2geo. The superiority of the catalyst was exhibited by low charge transfer resistance of about 6 Ohms, along with low Tafel slope of 43 mV dec−1. Further, the observed long‐term stability for 72 h and remarkable Faradaic efficiency with 99% indicate good durability and excellent selectivity towards OER, respectively. The superior activity of Fe−Ni3S4/NiS2is attributed to fast kinetics and low charge transfer resistance of the material facilitating the generation of active catalyst.
Mannich Reaction: An Alternative Synthetic Approach for Various Pyrrole‐Based Anion Receptors and Chelating Ligands
Authors: Guchhait Tapas , Roy Satabdi , Jena Priyadarshini
Published: June 2022

This review article highlights the synthetic design of various pyrrole‐based acyclic, tripodal, macrocyclic, and macrobicyclic Mannich bases and their applications, mainly as anion receptors. By varying the amine‐types and molar proportions of reagents, a range of value‐added Mannich bases are obtained. Herein, the synthesis and properties of several azacalixpyrroles, azacalixdipyrrolylmethanes, and azacryptands are discussed. Emphasis is also given to the applications of pyrrole‐based Mannich bases in the construction of some chelating ligands as one of the steps in multistep organic syntheses. In addition, the use of Mannich products as ligands for synthesizing metal complexes is also described. More importantly, the establishment of Mannich reactions as an alternative approach for traditionally used Schiff's base or aldehyde/ketone‐condensation reactions is delineated.
Synthesis of Diazo Compounds by Using NaN3 and Inexpensive SO2F2
Authors: Ye Cuijiao , Yan Zhaohua , Chen Guanghui , Xie Hongyan , Zhang Minxiang , Lin Sen
Published: June 2022

A concise and efficient method was developed in which sodium azide (NaN3) and sulfuryl fluoride (SO2F2) were directly employed to synthesize diazo compounds with active methylene compounds. A variety of diazo compounds were produced in good to excellent yields. This protocol avoids the use of organosulfonyl azides, and features atom economy and mild reaction conditions. An alternate method for the synthesis of diazo compounds was provided.
Discovery of KOH/BrCH2SO2F as Water‐Removable System for Clean, Mild and Robust Synthesis of Amides and Peptides
Authors: Wu Qi‐Xin , Shu Tao , Fang Wan‐Yin , Qin Hua‐Li
Published: June 2022

Herein we described an efficient, practical, and robust protocol for amides and peptides synthesis from carboxylic acids and amines using the combination of bromomethanesulfonyl fluoride (BMSF) with inorganic base KOH as a water‐removable system. This method is featured with broad substrate scope, excellent functional group compatibility, high yields, operational simplicity, and easy purification, which will exert great potential in amide and peptide synthesis.
Exploratory evaluation of tolerability, performance, and cosmetic acceptance of dexpanthenol‐containing dermo‐cosmetic wash and sun‐care products for tattoo aftercare
Authors: Schmid Daphné A. , Domingues Marisa P. , Nanu Alina , Kluger Nicolas , de Salvo Raffaella , Trapp Sonja
Published: June 2022

Background and Aims

Tattoo prevalence has significantly increased over the last decades. Proper tattoo aftercare, such as cleansing, moisturizing, and protection against sunlight, is essential to prevent complications and to keep the beauty of the tattoo. The tolerability, performance, and cosmetic acceptability of two dexpanthenol‐containing dermo‐cosmetic products, a wash and a sun‐care, were investigated on tattooed skin in two separate trials.

Methods

Two single‐center, exploratory, open‐label cosmetic studies were conducted between August and November 2020 to evaluate the dexpanthenol‐containing dermo‐cosmetic products. In the first study, healthy adults applied the 2.5% dexpanthenol‐containing wash right after their tattoo session daily for 14 consecutive days. In the second study, healthy adults applied the 2.5% dexpanthenol‐containing sun‐care sun protection factor 50+ cream on existing tattoos that were daily exposed to sunlight for 28 consecutive days. Clinical examination by a dermatologist and self‐assessment through subject questionnaires were used to assess the tolerability, acceptance, ease of use, and cosmetic outcomes of both products. Additionally, transepidermal water loss and moisturization assessments were performed to evaluate skin hydration after use of the sun‐care product.

Results

Both study products were well tolerated, and no product related adverse events were reported during the studies. At least 90% of the study participants appreciated the performance of the dexpanthenol‐containing wash and sun‐care product, including moisturizing properties, relief of unpleasant sensations, and preservation of the cosmetic appearance of the tattoo. For the sun‐care, it was shown that its application supported maintaining the skin barrier of tattooed skin, while keeping it hydrated.

Conclusion

The 2.5% dexpanthenol‐containing wash and sun‐care products are well tolerated and appreciated by tattooed subjects. Hence, they represent valid options for tattoo aftercare in line with current recommendations and practice.
Quantification of behavioral data with effect sizes and statistical significance tests
Authors: Costello Mack S. , Bagley Raymond F. , Fernández Bustamante Laura , Deochand Neil
Published: June 2022

This article describes the use of statistical significance tests and distance‐based effect sizes with behavioral data from single case experimental designs (SCEDs). Such data often are interpreted only with visual analysis. However, a growing movement in the field is to quantify results to improve decision‐making and communication across studies and sciences. The goal of the present study was to assess the agreement between visual analysis and various statistical tests. We recruited visual analysts to judge 160 pairwise data sets from published articles and compared these analyses to significance tests and effect sizes. One‐tailed significance testing of Tau z and the percentage of pairwise differences in the predicted direction (PWD) generally agreed with each other, and complemented the effect sizes of Ratio of Distances (RD) and g. Visual analysis was somewhat unreliable and should be combined with statistical complements to maximize decision accuracy.
Oxidized sodium alginate crosslinked silk fibroin composite scaffold for skin tissue engineering
Authors: Guo Yajin , Wang Xinyu , Li Binbin , Shen Ying , Shen Linyi , Wu Jiaxin , Yang Jing
Published: June 2022

Engineering skin substitutes represent a prospective source of advanced therapy in repairing severe traumatic wounds. Sodium alginate (SA) and silk fibroin (SF) are natural biomaterials, which are widely used in tissue engineering and other fields because of their low price, high safety, and good biocompatibility. However, SA itself degrades slowly, its degradation mode is difficult to control, and the degradation products are difficult to remove from the body because of its high molecular weight. Therefore, the composite scaffolds were prepared by freeze‐drying composite technology by using the Schiff base reaction between biocompatible SF and permeable oxidized sodium alginate (OSA). Sodium periodate was used as oxidant to modify SA. The results showed that higher oxidation degree of OSA could be obtained by increasing the proportion of oxidant, and the relative molecular weight of the oxidized products could also be reduced. The composite scaffolds were prepared by using sodium tetraborate as a crosslinking accelerator of the Schiff base reaction between OSA and SF. FT‐IR confirmed that the Schiff base group appeared in the material. In vitro biodegradation experiments showed that the biodegradation of the composite scaffolds was controllable, and the cytocompatibility experiment showed that the composite scaffolds had good biocompatibility.