bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasound phased arrays for prostate treatment
Authors: Tan Joseph S. , Frizzell Leon A. , Sanghvi Narendra , Wu Shih-jeh , Seip Ralf , Kouzmanoff Jeffrey T.
Published: July 2002

The effect of array geometry on the steering performance of ultrasound phased arrays is examined theoretically, in order to maximize array performance under the given anatomical constraints. This paper evaluates the performance of arrays with spherical and cylindrical geometry, determined by using computer simulations of the pressure fields produced at various extremes of steering. The spherical segment arrays were truncated for insertion into the rectum, and contained either annular or linear elements. The cylindrical arrays were either flat or had a variable curvature applied along their length. Fields were computed by dividing the array elements into many point sources. The effectiveness of an array configuration when steered to a particular focal location was assessed by defining a parameter, G, as the ratio of the intensity at the desired focus to the maximum intensity of any unwanted lobes. The performance of truncated spherical arrays with annular elements was evaluated for focal steering along the array axis (in depth, in the z direction). When steered 15 mm toward the source, these truncated spherical annular arrays exhibited excellent performance, with G>5.7 for arrays containing more than 10 elements. Similarly, the spherical arrays with linear elements performed well when steered along the array axis to the same degree, with G>7 (for element widths up to 3 λ), though many more array elements were required. However, when these arrays were steered 15 mm laterally, along the length of the prostate (the y direction), the value for G fell below 1 for element widths greater than about 1.6 λ. It was found that the cylindrical arrays performed much better for y-direction steering (G>4, for 60 mm arrays with an element width of 1.75 λ), but their performance was poorer when steered in the z direction (G≅4 for an element width of 1.5 λ). In order to find a compromise between these extremes, a curved cylindrical array was examined, which was a cylindrical array with additional curvature along its length. These curved cylindrical arrays yielded performance between that of spherical linear arrays and cylindrical arrays, with better steering along the y direction than the spherical arrays and better z-direction steering than the cylindrical arrays.
Middle-ear function with tympanic-membrane perforations. I. Measurements and mechanisms
Authors: Voss Susan E. , Rosowski John J. , Merchant Saumil N. , Peake William T.
Published: July 2002

Sound transmission through ears with tympanic-membrane (TM) perforations is not well understood. Here, measurements on human-cadaver ears are reported that describe sound transmission through the middle ear with experimentally produced perforations, which range from 0.5 to 5.0 mm in diameter. Three response variables were measured with acoustic stimulation at the TM: stapes velocity, middle-ear cavity sound pressure, and acoustic impedance at the TM. The stapes-velocity measurements show that perforations cause frequency-dependent losses; at low frequencies losses are largest and increase as perforation size increases. Measurements of middle-ear cavity pressure coupled with the stapes-velocity measurements indicate that the dominant mechanism for loss with TM perforations is reduction in pressure difference across the TM; changes in TM-to-ossicular coupling generally contribute less than 5 dB to the loss. Measurements of middle-ear input impedance indicate that for low frequencies, the input impedance with a perforation approximates the impedance of the middle-ear cavity; as the perforation size increases, the similarity to the cavity’s impedance extends to higher frequencies. The collection of results suggests that the effects of perforations can be represented by the path for air-volume flow from the ear canal to the middle-ear cavity. The quantitative description of perforation-induced losses may help clinicians determine, in an ear with a perforation, whether poor hearing results only from the perforation or whether other pathology should be expected.
Experimental observations of the stress experienced by a solid surface when a laser-created bubble oscillates in its vicinity
Authors: Shaw S. J. , Schiffers W. P. , Emmony D. C.
Published: July 2002

In an attempt to shed more light on the complex process by which cavities interact destructively with rigid boundaries we consider experimentally the interaction of a laser-generated bubble with a nearby solid boundary. To determine the stresses the surface of the boundary experiences, particularly during the final stages of the first collapse phase, we present a series of pressure transducer traces observed when the laser-created cavity is produced close to the solid boundary. Through careful control of experimental parameters we record pressure increases for cavities created between 0.56 and 1.5 times the maximum bubble radius from the solid boundary. Previous studies have shown this to be a complex process which is particularly sensitive to the working parameters of the problem, which is borne out by our observations.
Low-frequency echo-reduction and insertion-loss measurements from small passive-material samples under ocean environmental temperatures and hydrostatic pressures
Authors: Piquette Jean C. , Forsythe Stephen E.
Published: July 2002

System L is a horizontal tube designed for acoustical testing of underwater materials and devices, and is part of the Low Frequency Facility of the Naval Undersea Warfare Center in Newport, Rhode Island. The tube contains a fill fluid that is composed of a propylene glycol/water mixture. This system is capable of achieving test temperatures in the range of −3 to 40 deg Centigrade, and hydrostatic test pressures in the range 40 to 68 950 kPa. A unidirectional traveling wave can be established within the tube over frequencies of 100 to 1750 Hz. Described here is a technique for measuring the (normal-incidence) echo reduction and insertion loss of small passive-material samples that approximately fill the tube diameter of 38 cm. (Presented also is a waveguide model that corrects the measurements when the sample fills the tube diameter incompletely.) The validity of the system L measurements was established by comparison with measurements acquired in a large acoustic pressure-test vessel using a relatively large panel of a candidate material, a subsample of which was subsequently evaluated in system L. The first step in effecting the comparison was to least-squares fit the data acquired from the large panel to a causal material model. The material model was used to extrapolate the panel measurements into the frequency range of system L. The extrapolations show good agreement with the direct measurements acquired in system L.
Migration of backscatter data from the Mid-Atlantic Ridge
Authors: Harding Alistair J. , Hedlin Michael A. H. , Orcutt John A.
Published: July 2002

In studies of low-frequency reverberation within the marine environment, a central concern is the relationship between reverberation events and morphological features of the seafloor. A time-domain migration algorithm for the reverberation intensity field is developed that produces scattering coefficient maps coregistered with a bathymetry database. The algorithm is tailored to broadband transient sources with good range resolution, and was developed to analyze an extensive set of reverberation records from a 200–255 Hz source collected on the flanks of the Mid-Atlantic ridge. The precise, sample-by-sample, tracking of wavefronts across elements of the bathymetry database that forms the foundation of the algorithms implementation results in reverberation maps that show a clear and detailed correlation between scattering and morphology with narrow scarp slopes consistently highlighted. Environmentally induced asymmetries in transmission loss and incidence angle are exploited to break the inherent left–right ambiguity of the receiver array. Iterative migration, assuming a dominant dependence of backscatter on grazing angle, produces images, even from individual records, that show good ambiguity resolution. Results from multiple records corroborate the effectiveness of the ambiguity resolution and demonstrate the stability of the scattering coefficient estimates and the acoustic system.
A robust unit selection system for speech synthesis
Authors: Conkie Alistair
Published: July 2002

There has been interest for many years in diphone-based speech synthesis and, recently, a rapidly increasing interest in unit selection-based synthesis (as illustrated by interest in the CHATR system). The limits of both systems are well known. While intelligibility is generally very high for diphone-based systems, the resulting signals do not sound completely natural. This happens for several reasons, amongst them the limited number of phone variants present in a typical system, and the cost of concatenating at diphone boundaries. For unit selection synthesis, typically phone-based, it is possible to produce sentences that sound surprisingly natural and intelligible from a large database. However, quality is often not consistent, and the main difficulties appear to be related to selecting acoustically appropriate units from a large database with the correct prosodic characteristics. Typically no prosody modification is done. In an effort to capture the best features of both systems a unit-selection and synthesis algorithm has been devised that allows finer control than the CHATR system (version 0.8), both by applying selective prosody modification and by exercising finer control over the units that get chosen for synthesis. Results of experiments based on this version of unit selection synthesis will be presented.
Time-delay estimation of reverberated speech exploiting harmonic structure
Authors: Brandstein Michael S.
Published: July 2002

The relative time delay associated with a speech signal received at a pair of spatially separated microphones is a key component in talker localization and microphone array beamforming procedures. The traditional method for estimating this parameter utilizes the generalized cross correlation (GCC), the performance of which is compromised by the presence of room reverberations and background noise. Typically, the GCC filtering criteria used are either focused on the signal degradations due to additive noise or those due exclusively to multipath channel effects. There has been relatively little success at applying GCC weighting schemes which are robust to both of these conditions. This paper details an alternative approach which attempts to employ a signal-dependent criterion, namely, the estimated periodicity of the speech signal, to design a GCC filter appropriate for the combination of noise and multipath distortions. Simulations are performed across a range of room conditions to illustrate the utility of the proposed time-delay estimation method relative to conventional GCC filtering approaches.
A unified boundary element method for the analysis of sound and shell-like structure interactions. I. Formulation and verification
Authors: Chen Shaohai , Liu Yijun
Published: July 2002

A unified boundary element method (BEM) is developed in this paper to model both the exterior acoustic field and the elastic shell-like structure in a coupled analysis. The conventional boundary integral equation (BIE) for three-dimensional (3D) elastodynamics is applied to thin shell-like structures which can have arbitrary shapes and small thicknesses. The nearly singular integrals existing in the BIE when applied to thin bodies are transformed to nonsingular line integrals and are evaluated accurately and efficiently. For the exterior 3D acoustic domain, the Burton and Miller composite BIE formulation is employed to overcome the fictitious eigenfrequency difficulty (FED) and the thin-shape breakdown (TSB). Conforming C0 quadratic elements are employed in the discretization of the two sets of BIEs. The developed BIE formulations are valid for both radiation and scattering problems and for all wave numbers. Numerical examples using spherical and cylindrical shells, including nonuniform thickness and nondimensional wave numbers up to 12, clearly demonstrate the effectiveness and accuracy of the developed BEM approach.
Receiver operating characteristics and temporal integration in an insect auditory receptor cell
Authors: Tougaard Jakob
Published: July 2002

Receiver operating characteristics (ROC) analysis was applied to the problem of temporal integration in the A1 auditory receptor of the noctuid moth Noctua pronuba. The index of detectability (d′) was calculated either from ROC curves or from a procedure equivalent to a two-alternatives forced-choice paradigm of psychophysics. Stimuli of six different durations (1–40 ms) were used. The detectability increased exponentially with intensity for all signals and with the rate of increase independent of duration. This allowed for an evaluation of the influence of stimulus duration on detectability (duration/intensity trade-off). A model of statistical threshold improvement (the “multiple looks” model) could be applied and the influence of statistics on thresholds could be separated from the influence of intensity integration. For stimulus durations significantly shorter than the time constant of the receptor (3.4 ms for N. pronuba), intensity integration was the main factor determining thresholds and thus an energy detector model was applicable to the data. For durations significantly longer than the time constant, the multiple look model alone could account for changes in thresholds with duration. For durations in-between, a mixture of both models was applicable, making specific predictions difficult.
Backscattering enhancements from Rayleigh waves on the flat face of a tilted solid cylinder in water
Authors: Gipson Karen , Marston Philip L.
Published: July 2002

When the face of a finite solid elastic cylinder is ensonified by an acoustic wave, a variety of backscattering contributions associated with acoustic wave coupling into elastic waves are observed. A significant backscattering enhancement is observed for tilts such that the acoustic wave is incident on the face of the cylinder in the vicinity of the coupling angle for launching Rayleigh waves across the face. The observed backscattering indicates that the Rayleigh waves are reflected at the edge of the face and subsequently radiate acoustic waves in the backscattering direction. The measured backscattering is compared to an approximate theoretical prediction. Approximating the focusing of the Rayleigh wave after reflection at the (circular) edge by a Gaussian beam pressure distribution on the cylinder’s face yields simple expressions for the amplitude which are consistent with the measurements. In the vicinity of end-on incidence, other backscattering contributions due to the reflection of waves traveling down the length of the cylinder are observed. There is also evidence of a face-traversing longitudinal wave for slightly tilted cylinders.
Ultrasound sensitivity in the cricket, Eunemobius carolinus (Gryllidae, Nemobiinae)
Authors: Farris Hamilton E. , Hoy Ronald R.
Published: July 2002

Extracellular recordings from the cervical connectives in both long- and short-winged E. carolinus reveal auditory units that are sensitive to frequencies >15 kHz with best sensitivity at 35 kHz (79 dB SPL threshold). Stimuli in this frequency range also elicit a startle response in long-winged individuals flying on a tether. For single-pulse stimuli, startle and neck connective thresholds decrease with increasing ultrasound duration, consistent with the operation of an exponential integrator with a ∼32.5-ms time constant. There is evidence for adaptation to long duration pulses (>20 ms) in the neck connectives, however, as it is more difficult to elicit responses to the later stimuli of a series. For paired-pulse stimuli consisting of 1-ms pulses of 40 kHz, temporal integration was demonstrated for pulse separations <5 ms. For longer pulse separations, startle thresholds were elevated by 3 dB and appear to be optimally combined. Startle thresholds to 5 ms frequency modulated (FM) sweeps (60–30 kHz) and pure tone pulses (40 kHz) did not differ. The characteristics and sensitivity of this ultrasound-induced startle response did not differ between males and females. As in some other tympanate insects, ultrasound sensitivity in E. carolinus presumably functions in the context of predation from echolocating bats.
Acoustic load on the ear caused by headphones
Authors: Vorländer Michael
Published: July 2002

The standardized method for measurement of complex impedances according to ISO 10534 Part 2 is applied to the acoustic impedance of the ear with an “open-pinna” condition and with different types of headphones. The method is based on measurement of the transfer function of two microphone locations in an impedance tube and subsequent signal processing of the complex signal spectra. The termination of the tube is interpreted as ear canal entrance, while the measurement direction is, apparently, from “inside” the head towards outside. A tube which was specifically designed for this purpose works well, even though extremely small impedances must be measured. The impedances of the free pinna are similar to the “soft” end condition in the open tube, approximately following the radiation impedance of a piston into free space. The headphone impedances can be separated according to the type of headphone. In addition, the absolute impedances as the differences to the open ear compared with a number of headphones are interesting and may be starting point for further investigations. One possibility is, of course, quality control of headphones. The results are also expected to be useful for psychoacoustic research, for better understanding of sound perception, and for use in development of audio equipment.
A thermoacoustic-Stirling heat engine: Detailed study
Authors: Backhaus S. , Swift G. W.
Published: July 2002

A new type of thermoacoustic engine based on traveling waves and ideally reversible heat transfer is described. Measurements and analysis of its performance are presented. This new engine outperforms previous thermoacoustic engines, which are based on standing waves and intrinsically irreversible heat transfer, by more than 50%. At its most efficient operating point, it delivers 710 W of acoustic power to its resonator with a thermal efficiency of 0.30, corresponding to 41% of the Carnot efficiency. At its most powerful operating point, it delivers 890 W to its resonator with a thermal efficiency of 0.22. The efficiency of this engine can be degraded by two types of acoustic streaming. These are suppressed by appropriate tapering of crucial surfaces in the engine and by using additional nonlinearity to induce an opposing time-averaged pressure difference. Data are presented which show the nearly complete elimination of the streaming convective heat loads. Analysis of these and other irreversibilities show which components of the engine require further research to achieve higher efficiency. Additionally, these data show that the dynamics and acoustic power flows are well understood, but the details of the streaming suppression and associated heat convection are only qualitatively understood.
Tests of auditory–visual integration efficiency within the framework of the fuzzy logical model of perception
Authors: Massaro Dominic W. , Cohen Michael M.
Published: July 2002

The fuzzy logical model of perception [FLMP, Massaro, Perceiving Talking Faces: From Speech Perception to a Behavioral Principle (MIT Press, Cambridge, MA, 1998)] has been extremely successful at describing performance across a wide range of ecological domains as well as for a broad spectrum of individuals. Because the model predicts optimal or maximally efficient integration, an important issue is whether this is the case for most individuals. Three databases are evaluated to determine to what extent a significant quantitative improvement in predictive ability can be obtained if integration is assumed to be somewhat inefficient. For the most part, there were no significant signs of inefficient integration. The previous differences found by Grant and Seitz [J. Acoust. Soc. Am. 104, 2438–2450 (1998)] must be due to their measures of efficiency, which appear to be invalid and/or conflate information with integration efficiency. Finally, the descriptive ability of the FLMP is shown to be theoretically informative and not simply the model’s ability to describe any possible outcome.
Measuring the Extensional Rheology of Polymer Melts
Authors: Cogswell F. N.
Published: July 2002

A necessary prerequisite of the scientific design of polymer processing operations is a fundamental understanding of the rheology of melts. In fiber spinning the dominant rheological response has simple extensional geometry and we require information about viscosity, elasticity, and fracture during such flows. Industry needs both absolute quantitative information and also inexpensive qualitative tests for multiple samples. Experimentation demands the greatest quantity of accurate information at minimum cost, and this philosophy underlies a critical revue of approaches to measuring the rheology of polymer melts under tension. The decisive techniques so far developed lack versatility and are not suitable for multiple testing. The continuous drawing of a monofilament, or laboratory spinning, is an excellent qualitative approach but sufficient experimental control has yet to be attained. Two indirect routes, through normal stresses to a “normal” viscosity and by steady shear/dynamic rheometry correlation to an “irrotational” viscosity, are superficially attractive but theoretical complexity is a major problem. The most promising industrial approach is the study of converging flows. Analysis of melt flowing from a reservoir into a die yields a simple method of obtaining apparent extensional rheology data which is compatible with, and supplementary to, the results offered by the direct methods of measurement. The analysis allows the ubiquitous capillary rheometer to become a simple extensional flow meter. It is the alliance of the definitive, but costly and temperamental, methods with inexpensive simple qualitative techniques that forges rheological tools for tackling industrial problems.
Droplet deformation in polymer blends during uniaxial elongational flow: Influence of viscosity ratio for large capillary numbers
Authors: Delaby I. , Ernst B. , Germain Y. , Muller R.
Published: July 2002

The deformation in uniaxial elongational flow of dispersed droplets in immiscible molten polymer blends was studied for viscosity ratios 0.005<p=η(drop)/η(matrix)<13 and negligible interfacial tension, with an original method based on quenching elongated specimens. Although drop deformations (drop major axis over initial diameter) were in the range 1≤λd≤5, good overall agreement was found with the small deformation Newtonian theory, which predicts that the drop versus matrix deformation ranges from 5/3 to 0 when p increases from 0 to infinity. The theoretical prediction that for p lower than 1, the droplet should deform more than the faraway surrounding matrix, with a limiting ratio of 5/3 at vanishing droplet viscosity, was verified both experimentally and numerically with a finite element simulation.
Inhibition of Sympathetic Activation by Delivering Calcium Channel Blockers from a 3D Printed Scaffold to Promote Bone Defect Repair
Authors: Li Shikai , Li Zhihui , Yang Jin , Ha Yujie , Zhou Xiaojun , He Chuanglong
Published: June 2022

Enhancing osteogenesis by promoting neural network reconstruction and neuropeptide release is considered to be an attractive strategy for repairing of critical size bone defects. However, traumatic bone defects often activate the damaged sympathetic nervous system (SNS) in the defect area and release excessive catecholamine to hinder bone defect repair. Herein, a 3D printed scaffold loaded with the calcium channel blocker‐nifedipine is proposed to reduce the concentration of catecholamine present in the bone defect region and to accelerate bone healing. To this end, nifedipine‐loaded ethosome and laponite are added into a mixed solution containing sodium alginate, methacrylated gelatin, and bone mesenchymal stem cells (BMSCs) to prepare a cell‐laden scaffold using 3D bioprinting. The released nifedipine is able to close the calcium channels of nerve cells, thereby blocking sympathetic activation and ultimately inhibiting the release of catecholamine by sympathetic nerve cells, which further promotes the osteogenic differentiation and migration of BMSCs, inhibits osteoclastogenesis in vitro, and effectively improves bone regeneration in a rat critical‐size calvarial defect model. Therefore, the results suggest that sustained release of nifedipine from the scaffold can effectively block SNS activation, providing promising strategies for future treatment of bone defects.
Configuration of Methylammonium Lead Iodide Perovskite Solar Cell and its Effect on the Device's Performance: A Review
Authors: Dahal Biplav , Li Wenzhi
Published: June 2022

In its initial phase in 2009, the inorganic‐organic hybrid perovskite solar cells (PSCs) delivered a 3.8% power conversion efficiency (PCE), which is far below the present 25.7% PCE obtained in 2022. The significant improvement of the efficiency of PSCs in such a short period has stimulated significant interest in the photovoltaic community. However, the performance of current PSCs is behind the commercially available and widely used solar cells in terms of stability and scalability. Among various commonly studied perovskite materials, methylammonium lead iodide (MAPbI3) is the most widely studied. This review will focus on the common solar cell structures (mesoporous, inverted planar p‐i‐n, planar n‐i‐p) using MAPbI3 perovskite as an active layer and the effect of these solar cell structures on their performances. Furthermore, some commonly‐used strategies are outlined for improving the device performance, such as optimizing the deposition technique of the charge transporting and the active layers, modifying the properties of the carrier transporting layer and the perovskite layer by interface engineering and doping, optimizing the perovskite surface morphology, along with others. This article will also discuss the hole transport free and electron transport free MAPbI3 PSCs.
Modeling Time‐Resolved Kinetics in Solids Induced by Extreme Electronic Excitation
Authors: Medvedev Nikita , Akhmetov Fedor , Rymzhanov Ruslan A. , Voronkov Roman , Volkov Alexander E.
Published: June 2022

The authors present a concurrent Monte Carlo (MC)–molecular dynamics (MD) approach to modeling matter response to excitation of its electronic system at nanometric scales. The two methods are combined on‐the‐fly at each time step in one code, TREKIS‐4. The MC model describes the arrival of irradiation (a photon, an electron, or a fast ion). It traces induced cascades of secondary electrons and holes, and their energy exchange with atoms due to scattering. The excited atomic system is simulated with an MD model. An efficient way is proposed to account for nonthermal effects in the electron‐atom energy transfer in covalent materials via the conversion of the potential energy of the electronic ensemble into the kinetic energy of atoms. Such a combined MC–MD approach enables a time‐resolved tracing of the excitation kinetics of both, the electronic and atomic systems, and their simultaneous response to a deposited dose. As a proof‐of‐principle, it is shown that the proposed method describes atomic dynamics after X‐ray irradiation in good agreement with tight‐binding MD. The model also allows gaining insights into the atomic system behavior during the energy deposition from a nonequilibrium electronic system excited by an ion impact.
Retracted: Dual‐Ion Stabilized Layered Structure of OVO for Zero‐Strain Potassium Insertion and Extraction
Authors: Wang Jianyi , Chen Menghui , Chen Zhida , Lu Zicong , Si Liping
Published: June 2022

Potassium‐ion batteries (KIB) have similar energy storage mechanism with lithium‐ion battery, but the potassium (K) resource is rich, which shows great potential for large‐scale energy storage system. Recently, the anode materials of KIB studied mainly include carbon materials, transition metal oxides, and alloy materials. The amorphous hard carbon shows the best comprehensive performance, but its intercalation potential is close to 0 V (versus K+/K), which is easy to cause K dendrite and brings security risks. The oxide materials have high capacity but high intercalation potential, low first cycle efficiency, and unstable cycle. Here, based on the understanding of the K intercalation mechanism of vanadium oxides, a novel zero strain anode material with layered structure of dual‐ions (Na+/K+) is designed (NaK(VO3)2V2O5). The introduction of Na/K ion contributed to the transmission and further stabilized the structure. It has an excellent rate performance (10 A g−1, up to 25 000th cycle), and its special K storage mechanism and zero‐strain characteristics are revealed for the first time by ex situ scanning electron microscope, X‐ray powder diffraction, X‐ray photoelectron spectroscopy, and other test methods. Considering the excellent performance endowed by these unique inherent properties, NaK(VO3)2V2O5 shows great potential for commercial anode materials and may promote the innovation of KIB.
Optimization of a multiperiod refinery planning problem under uncertainty
Authors: Boucheikhchoukh Ariel A. , Swartz Christopher L. E. , Bouveresse Eric , Lutran Pierre , Robert Anna
Published: June 2022

Uncertainty in refinery planning presents a significant challenge in determining the day‐to‐day operations of an oil refinery. Deterministic modeling techniques often fail to account for this uncertainty, potentially resulting in reduced profit. The stochastic programming framework explicitly incorporates parameter uncertainty in the problem formulation, thus giving preference to robust solutions. In this work, a nonlinear, multiperiod, industrial refinery problem is extended to a two‐stage stochastic problem, formulated as a mixed‐integer nonlinear program. A crude‐oil sequencing case study is developed with binary scheduling decisions in both stages of the stochastic programming problem. Solution via a decomposition strategy based on the generalized Benders decomposition (GBD) algorithm is proposed. The binary decisions are designated as complicating variables that, when fixed, reduce the full‐space problem to a series of independent scenario subproblems. Through the application of the GBD algorithm, a feasible mixed‐integer solution is obtained that is more robust to uncertainty than its deterministic counterpart.
Association of neighborhood socioeconomic disadvantage and cognitive impairment
Authors: Vassilaki Maria , Aakre Jeremiah A. , Castillo Anna , Chamberlain Alanna M. , Wilson Patrick M. , Kremers Walter K. , Mielke Michelle M. , Geda Yonas E. , Machulda Mary M. , Alhurani Rabe E. , Graff‐Radford Jonathan , Vemuri Prashanthi , Lowe Val J. , Jack Clifford R. , Knopman David S. , Petersen Ronald C.
Published: June 2022

Introduction

We investigated the association of the area deprivation index (ADI) with cognitive decline, mild cognitive impairment (MCI), and dementia in older adults (≥50 years old). ADI is a neighborhood socioeconomic disadvantage measure assessed at the census block group level.

Methods

The study included 4699 participants, initially without dementia, with available ADI values for 2015 and at least one study visit in 2008 through 2018. Using logistic regression and Cox proportional hazards models with age as the time scale, we assessed the odds for MCI and the risk for dementia, respectively.

Results

In cognitively unimpaired (CU) adults at baseline, the risk for progression to dementia increased for every decile increase in the ADI state ranking (hazard ratio = 1.06, 95% confidence interval (1.01–1.11), P = .01). Higher ADI values were associated with subtly faster cognitive decline.

Discussion

In older CU adults, higher baseline neighborhood socioeconomic deprivation levels were associated with progression to dementia and slightly faster cognitive decline.

Highlights

The study used area deprivation index, a composite freely available neighborhood deprivation measure.

Higher levels of neighborhood deprivation were associated with greater mild cognitive impairment odds.

Higher neighborhood deprivation levels were associated with higher dementia risk.
Augmented catalytic effect of nano‐bi‐transition metal ferrite NiZnFe2O4 for nano‐nitrotriazolone thermolysis
Authors: Dave Pragnesh N. , Thakkar Riddhi , Sirach Ruksana
Published: June 2022

The present research aims to study the thermolysis behavior of nano‐nitrotriazolone (nNTO) with and with catalyst bi‐transition metal ferrite (NiZnFe2O4‐NZF). Synthesized NTO via consecutive reaction method was modified to nanosize by using solvent–antisolvent method, while co‐precipitation method was used for the preparation of ferrite. Their physico‐chemical characteristics have been investigated in detail by using X‐ray diffraction (XRD), field emission gun scanning electron microscope (FEG‐SEM), Fourier transform infrared (FTIR), Raman, and ultraviolet–visible (UV–vis) analytical techniques. The catalytic performance was studied briefly using simultaneous thermal analyses. The average crystalline size of NZF is found between 12 and 25 nm, while NTO and nNTO are found between 15 and 40 nm. The nNTO derived from NTO showed higher crystallinity and less agglomeration, while NZF has nanoparticles with polyhedral shape. The thermal results are depicted that this catalyst worked superior to enhance thermolysis of nNTO than its mixture with NTO and it was evaluated by the various kinetic model. The kinetic mean values revealed that nNTO + NZF activation energy decreased in the range of 100–150 kJ mol−1. According to the obtained results, such kind of catalyst has been used for the preparations of explosive energetic formulations that are widely applicable in rocketry development.
Silver‐Promoted Decarboxylative Difluoromethylenation of α,β‐Unsaturated Carboxylic Acids for the Synthesis of Allylic Difluorides
Authors: Li Hongxiao , Sun Qianqian , Zhang TianTian , Chen Yunrong , Zhang Jianhua , Deng Hongmei , Jiang Haizhen
Published: June 2022

An efficient silver‐promoted decarboxylative gem‐difluoromethylenation of aryl‐ or alkyl‐substituted α,β‐unsaturated carboxylic acids with readily available benzo‐1,3‐diazolic difluoromethyl bromides has been developed. This convenient transformation demonstrated good functional‐group tolerability and broad substrate scope, and afforded the allylic difluorides in good to excellent yields with exclusive E‐stereoselectivity under mild reaction conditions.
NIL collectives could trigger Title IX scrutiny
Authors: McCarthy Claudine
Published: June 2022

The name, image, and likeness issue is already complicated enough as it is, but if you don't pay attention to the intersection of Title IX compliance and NIL collectives, you'll likely end up facing the perfect storm.
Kaposi’s sarcoma associated with chronic myeloid leukemia and imatinib mesylate therapy
Authors: D’Addona Matteo , Pezzullo Luca , Giudice Valentina , Serio Bianca , Baldi Carlo , Zeppa Pio , Selleri Carmine
Published: June 2022

Kaposi's sarcoma is associated with immunosuppression and human herpesvirus 8 infection, while rarely described in myeloid malignancies. Here, we illustrate a rare case of chronic myeloid leukemia treated with imatinib, a tyrosine kinase inhibitor, who developed a human herpesvirus 8‐related Kaposi's sarcoma.
Multiplexed single‐cell analysis of FNA allows accurate diagnosis of salivary gland tumors
Authors: Oh Juhyun , Yoo Tae Yeon , Saal Talia M. , Tsay Lisa , Faquin William C. , Carlson Jonathan C.T. , Deschler Daniel G. , Pai Sara I. , Weissleder Ralph
Published: June 2022

Diagnosing salivary gland tumors (SGTs) through fine‐needle aspiration (FNA) biopsies is challenging due to the overlapping cytomorphologic features between benign and malignant tumors. The authors developed an innovative, multiplexed cycling technology for the rapid analyses of single cells obtained from FNA that can facilitate the molecular analyses and diagnosis of SGTs. Antibodies against 29 protein markers associated with 7 SGT subtypes were validated and chemically modified via custom linker–bio‐orthogonal probes (FAST). Single‐cell homogenates and FNA samples were profiled by FAST cyclic imaging and computational analysis. A prediction model was generated using a training set of 151,926 cells from primary SGTs (N = 26) and validated on a separate cohort (N = 30). Companion biomarker testing, such as neurotrophic tyrosine receptor kinase (NTRK), was also assessed with the FAST technology. The FAST molecular diagnostic assay was able to distinguish between benign and malignant SGTs with an accuracy of 0.86 for single‐cell homogenate samples and 0.88 for FNA samples. Profiling of multiple markers as compared to a single marker increased the diagnostic accuracy (0.82 as compared to 0.65‐0.74, respectively), independent of the cell number sampled. NTRK expression was also assessed by the FAST assay, highlighting the potential therapeutic application of this technology. Application of the novel multiplexed single‐cell technology facilitates rapid biomarker testing from FNA samples at low cost. The customizable and modular FAST‐FNA approach has relevance to multiple pathologies and organ systems where cytologic samples are often scarce and/or indeterminate resulting in improved diagnostic workflows and timely therapeutic clinical decision‐making.
The value of monitoring amended reports in cytopathology quality programs: A biennial review
Authors: Torous Vanda F. , Pitman Martha B. , Heher Yael K.
Published: June 2022

Background

Quality and safety are the foundation of the practice of cytopathology. Review of key performance indicator (KPI) data can shine a light on laboratory vulnerabilities and potential areas for targeted improvement. The rate and content of amendment reports is a frequently monitored KPI in anatomic pathology, but few have studied its value in cytopathology. The goal of this study was to examine the frequency, classification, and outcome of amendments for a large cytopathology laboratory.

Methods

All amendment reports issued for cases during a 2‐year period from July 2019 to June 2021 were included in the study. Amendments were classified into three error type root causes: Specimen Identification Error, General Report Defects, and Diagnostic Error.

Results

A total of 202 amendment reports were issued equating to a rate of 0.275%. A total of 83 (41.1%) were gynecologic cases and 119 (58.9%) were nongynecologic cases. Within the gynecologic cases, 13 (15.7%) cases were due to Specimen Identification Error, 13 (15.7%) cases were due to Diagnostic Error, and 57 (68.7%) cases were due to General Report Defects. Within the nongynecologic cases, 15 (12.6%) cases were due to Specimen Identification Error, 30 (25.2%) cases were due to General Report Defects, and 74 (62.2%) cases were due to Diagnostic Error with 32 of these due to true diagnostic change. Discovery methods included following re‐review after additional clinical information was provided, reinterpretation after additional ancillary testing was performed, or conference review. There was no correlation with years in practice.

Conclusions

Studying amendment reports is an underrecognized and valuable quality assurance tool. Amendments can help provide information about types of errors, monitor laboratory processes, and help guide quality improvement endeavors.
Field quantifications of probability of detection and search patterns to form protocols for the use of detector dogs for eradication assessments
Authors: Hoffmann Benjamin D. , Faulkner Craig , Brewington Laura , Lawton Faye
Published: June 2022

The use of detector dogs within environmental programs has increased greatly over the past few decades, yet their search methods are not standardized, and variation in dog performance remains not well quantified or understood. There is much science to be done to improve the general utility of detector dogs, especially for invertebrate surveys.

We report research for detector dog work conducted as part of yellow crazy ant eradication. One dog was first used to quantify the probability of detection (POD) within a strictly controlled trial. We then investigated the search patterns of two dogs when worked through sites using different transect spacings. Specifically, we quantified their presence within set distances of all locations in each assessment area, as well as the time they took to assess each area. In a GIS, we then calculated the relative percentage of the entire search area within six distance categories, and combined this information with the POD values to obtain a site‐level POD.

The calculated relationship between distance and POD was extremely strong (R2 = 0.998), with POD being 86% at 2 m and 28% at 25 m. For site‐level assessments conducted by the two dogs, both dogs achieved the highest site‐level POD when operated on the lowest transect spacing (15 m), with POD decreasing significantly as transect spacing increased. Both dogs had strong linear relationships between area assessed and time, with the area assessed being greater when the transects had greater spacing. The working style of the two dogs also resulted in significantly different assessment outcomes. In 1 h one dog could assess approximately 9.2 ha with transects spaced 20 m apart, and 6.8 ha with transects spaced 15 m apart, whereas the second dog could only assess approximately 6.9 ha with transects spaced 20 m apart, and 4.9 ha with transects spaced 15 m apart.

Our study provides insight into the ability of dogs to detect yellow crazy ants, and sets the basis for further science and protocol development for ant detection. With the lessons learned from this work, we then detail protocols for using detector dogs for ant eradication assessments.
Characterization and real‐time hybrid simulation testing of rolling pendulum isolation bearings with different surface treatments
Authors: Covarrubias Vargas Braulio A. , Harvey P. Scott , Cao Liang , Ricles James M. , Al‐Subaihawi Safwan , Villalobos Vega Esteban
Published: June 2022

Damage caused by earthquakes to buildings and their contents (e.g., sensitive equipment) can impact life safety and disrupt business operations following an event. Floor isolation systems (FISs) are a promising retrofit strategy for protecting vital building contents. In this study, real‐time hybrid simulation (RTHS) is utilized to experimentally incorporate multi‐scale (building–FIS–equipment) interactions. For this, an experimental setup representing one bearing of a rolling pendulum (RP) based FIS is studied—first through characterization tests and then through RTHS. A series of tests was conducted at the Natural Hazards Engineering Research Infrastructure (NHERI) Experimental Facility at Lehigh University. Multiple excitations were used to study the experimental setup under uni‐axial loading. Details of the experimental testbed and test protocols for the characterization and RTHS tests are presented, along with results from these tests, which focused on the effect of different rolling surface treatments for supplemental damping, the FIS–equipment and building–FIS interactions, and rigorous evaluation of different RP isolation bearing designs through RTHS.
Increasing selection of and engagement in physical activity in children with autism spectrum disorder
Authors: Goldman Kissel J. , DeLeon Iser G.
Published: June 2022

Children with autism spectrum disorder (ASD) engage in reduced levels of physical activity relative to neurotypical children. Researchers conducted 2 studies to 1) evaluate the influence of the number of physical activity options and effort on choice and 2) develop a token‐based intervention to increase physical activity engagement and evaluate whether the opportunity to access the intervention supported responding similar to physical or sedentary activity alone. Four children with ASD participated. Additional physical activity options alone did not increase physical activity selection, but increased effort reduced selection of sedentary activity. Tokens increased physical activity for 2 participants. A combination of physical and sedentary activities maintained as much as or more responding than either activity in isolation for all participants. Limitations and potential areas of future research on choice and physical activity are discussed.
Multidisciplinary biophotonics, open science, and … plug & pray deep learning?
Authors: Opstad Ida S.
Published: June 2022

Due to its great creative potential for innovation and scientific discovery, inter‐ and multidisciplinary collaboration is being increasingly encouraged by institutions and funding agencies. The increased opportunities in the multidisciplinary arena also come with significant challenges like the added experimental, analytical and logistical complexity, blended with a high likelihood of miscommunications. When is multidisciplinarity worth the effort, and how can we be better collaborators? With a focus on cross‐disciplinary collaborative work to answer burning questions in biology and biomedicine, this paper discusses both large challenges and opportunities with multidisciplinary biophotonics, how we can better navigate the arena of big data and artificial intelligence combined with open, reproducible science and biological discoveries.
Density functional theory and CCSD(T) evaluation of ionization potentials, redox potentials, and bond energies related to zirconocene polymerization catalysts
Authors: Maley Steven M. , Lief Graham R. , Buck Richard M. , Sydora Orson L. , Yang Qing , Bischof Steven M. , Ess Daniel H.
Published: June 2022

Quantum‐mechanical‐based computational design of molecular catalysts requires accurate and fast electronic structure calculations to determine and predict properties of transition‐metal complexes. For Zr‐based molecular complexes related to polyethylene catalysis, previous evaluation of density functional theory (DFT) and wavefunction methods only examined oxides and halides or select reaction barrier heights. In this work, we evaluate the performance of DFT against experimental redox potentials and bond dissociation enthalpies (BDEs) for zirconocene complexes directly relevant to ethylene polymerization catalysis. We also examined the ability of DFT to compute the fourth atomic ionization potential of zirconium and the effect the basis set selection has on the ionization potential computed with CCSD(T). Generally, the atomic ionization potential and redox potentials are very well reproduced by DFT, but we discovered relatively large deviations of DFT‐calculated BDEs compared to experiment. However, evaluation of BDEs with CCSD(T) suggests that experimental values should be revisited, and our CCSD(T) values should be taken as most accurate.