bluuebunny/crossref_metadata_2025 huggingface dataset:
Controllable patterns and streaming of plane acoustic vortex with annular piezoelectric arrays excitation
Authors: Fan Yiqiang , Zhang Jie , Wei Bin , Drinkwater Bruce W.
Published: March 2021

In this paper, an annular array consisting of 64 piezoelectric ceramics was established to make acoustic vortices. The trapped particles and streaming lines in the fluid chamber were theoretically designed and manipulated in experiment. The acoustic field was simulated by Bessel functions and the principle of Huygens by a hydrophone with the annular array excitation. An fast Fourier transform comparison method was proposed in experiments to get the acoustic vortices and phase patterns. The results showed that the patterns of the acoustic field were much different from each other with the variation of excitation phases and the phase patterns implied the vortices in fluid of the chamber, which were affected by the annular arrays of piezoelectric slice excitation. The research concluded that the trapped area and streaming lines can be manipulated by adjusting the phase of piezoelectric slices and the experimental data were helpful to guide the design of acoustic tweezers.
Canard oscillations in the randomly forced suspension flows
Authors: Bashkirtseva Irina , Ryashko Lev
Published: March 2021

Complex canard-type oscillatory regimes in stochastically forced flows of suspensions are studied. In this paper, we use the nonlinear dynamical model with a N-shaped rheological curve. Amplitude and frequency characteristics of self-oscillations in the zone of canard explosion are studied in dependence on the stiffness of this N-shaped function. A constructive role of random noise in the formation of complex oscillatory regimes is investigated. A phenomenon of the noise-induced splitting of stochastic cycles is discovered and studied both numerically and analytically by the stochastic sensitivity technique. Supersensitive canard cycles are described and their role in noise-induced transitions from order to chaos is discussed.
Use of flicker noise in polyaniline to determine the product of mobility and lifetime of charge carriers
Authors: Toušek Jiří , Rutsch Radka , Křivka Ivo , Toušková Jana
Published: March 2021

The current passing through a polyaniline layer generates electrical fluctuations, the amplitude of which increases in a part of the frequency spectrum with the inversion of the frequency f. It is deduced that this is due to the behavior of charge carriers trapped on energy levels in the bandgap. If these localized carriers are in equilibrium with the valence band, a frequency range can be found where the lifetime is inversely proportional to the frequency. Electron jumps between the levels and the valence band are manifested by the generation of electrical noise signals. The slope of the dependence of the noise current on 1/f was calculated, and the product of the mobility and lifetime of the holes was determined.
High-amplitude sound propagation in acoustic transmission-line metamaterial
Authors: Zhang Jiangyi , Romero-García Vicente , Theocharis Georgios , Richoux Olivier , Achilleos Vassos , Frantzeskakis Dimitrios J.
Published: March 2021

We report experiments on high-amplitude sound wave propagation in an acoustic metamaterial composed of an air-filled waveguide periodically side-loaded by holes. In addition to the linear viscothermal and radiation losses, high amplitude sound waves at the locations of the side holes introduce nonlinear losses. The latter result in an amplitude-dependent reflection, transmission, and absorption, which we experimentally characterize. First, we evidence that nonlinear losses change the nature of the device from a reflective to an absorbing one, showing the possibility to use the system as a nonlinear absorber. Second, we study the second-harmonic generation and its beating phenomenon both experimentally and analytically. We find that when considering the propagation of both the fundamental and the second harmonic, nonlinear losses cannot be neglected. Our results reveal the role of nonlinear losses in the proposed device and also provide a quite accurate analytical model to capture the effect of such losses.
Combinatorial tuning of electronic structure and thermoelectric properties in Co2MnAl1−xSix Weyl semimetals
Authors: Modak Rajkumar , Goto Kazuki , Ueda Shigenori , Miura Yoshio , Uchida Ken-ichi , Sakuraba Yuya
Published: March 2021

Tuning of the Fermi level (EF) near Weyl points is one of the promising approaches to realize the large anomalous Nernst effect (ANE). In this work, we introduce an efficient approach to tune EF for the Co2MnAl Weyl semimetal through a layer-by-layer combinatorial deposition of the Co2MnAl1−xSix (CMAS) thin film. A single-crystalline composition-spread film with x varied from 0 to 1 was fabricated. The structural characterization reveals the formation of a single-phase CMAS alloy throughout the composition range with a gradual improvement of L21 order with x similar to the co-sputtered single layered film, which validates the present fabrication technique. Hard x-ray photoemission spectroscopy for the CMAS composition-spread film directly confirmed the rigid band-like EF shift of ∼0.40 eV toward the composition gradient direction from x = 0 to 1. The anomalous Ettingshausen effect (AEE), the reciprocal of the ANE, has been measured for the whole x range using a single strip along the composition gradient using the lock-in thermography technique. The similarity of the x dependence of observed AEE and ANE signals clearly demonstrates that AEE measurement on the composition-spread film is an effective approach to investigate the composition dependence of the ANE of Weyl semimetal thin films and realize the highest performance without fabricating several films, which will accelerate the research on ANE-based energy harvesting.
Automated pick-and-place of single nanoparticle using electrically controlled low-surface energy nanotweezer
Authors: Lyu Ya-Kun , Ji Zuo-Tao , He Tao , Lu Zhenda , Zhang Weihua
Published: March 2021

In this work, we developed electrically controlled nanotweezers, which are capable of picking, moving, and placing a single sub-50 nm particle precisely and repeatably in ambient air. The nanotweezers are made of a fluoride polymer coated conductive atomic force microscope tip. By applying voltages on such a low surface energy tip, one can tune the binding energy between the tip and the nanoparticle up and down and consequently pick and place a nanoparticle with a high success rate (>90%). Moreover, we automated the whole pick-and-place procedure with the help of the computer vision technique, and it allows us to pattern nanoparticles into arbitrary patterns without any manual operation.
Airborne transmission of virus-laden aerosols inside a music classroom: Effects of portable purifiers and aerosol injection rates
Authors: Narayanan Sai Ranjeet , Yang Suo
Published: March 2021

The ongoing COVID-19 pandemic has shifted attention to the airborne transmission of exhaled droplet nuclei within indoor environments. The spread of aerosols through singing and musical instruments in music performances has necessitated precautionary methods such as masks and portable purifiers. This study investigates the effects of placing portable air purifiers at different locations inside a classroom and the effects of different aerosol injection rates (e.g., with and without masks, different musical instruments, and different injection modes). Aerosol deposition, airborne concentration, and removal are analyzed in this study. It was found that using purifiers could help in achieving ventilation rates close to the prescribed values by the World Health Organization, while also achieving aerosol removal times within the Center of Disease Control and Prevention recommended guidelines. This could help in deciding break periods between classroom sessions, which was around 25 min through this study. Moreover, proper placement of purifiers could offer significant advantages in reducing airborne aerosol numbers (offering several orders of magnitude higher aerosol removal when compared to nearly zero removal when having no purifiers), and improper placement of the purifiers could worsen the situation. This study suggests the purifier to be placed close to the injector to yield a benefit and away from the people to be protected. The injection rate was found to have an almost linear correlation with the average airborne aerosol suspension rate and deposition rate, which could be used to predict the trends for scenarios with other injection rates.
Cation effect of inorganic salts on ionic Seebeck coefficient
Authors: Shu Yue , Odunmbaku George Omololu , He Yongjie , Zhou Yongli , Cheng Hanlin , Ouyang Jianyong , Sun Kuan
Published: March 2021

Ionic thermoelectric materials attract widespread attention due to their large Seebeck coefficient compared with electronic thermoelectric counterparts whose main charge carriers are electrons or holes. The present work shows that the ion-polymer matrix interaction can alter the Seebeck coefficient to a great extent. To further shed light on the role of ions, seven water-soluble inorganic chlorides are utilized in this work, to highlight the influence of the cationic softness parameter on the Seebeck coefficient in a PEDOT:PSS ionic conductor. We notice that cations with a positive or a small negative softness parameter value exhibit a negative Seebeck coefficient, resulting from limited thermal diffusion of the cations that are strongly bound to PSS- anions. Conversely, cations with a sufficiently negative softness parameter exhibit fast thermal diffusion due to weak binding to PSS- and, thus, lead to a positive Seebeck coefficient. Based on the established relationship, robust thermoelectric materials with a tunable Seebeck coefficient ranging from –9.63 mV/K to +3.07 mV/K are demonstrated. Our work highlights the important role of ionic properties and provides a pathway for the rational selection of ions in ionic thermoelectrics.
Colossal enhancement of the thermoelectric power factor in stress-released orthorhombic phase of SnTe
Authors: Morozova Natalia V. , Korobeynikov Igor V. , Ovsyannikov Sergey V.
Published: March 2021

At normal conditions, tin telluride (SnTe) adopts a cubic NaCl-type structure, but under applied pressure above 1.5–2 GPa, it transforms to a distorted crystal structure with an orthorhombic symmetry. Electronic properties of this high-pressure phase, including potential thermoelectricity, remain unexplored to date. Here, we measure the thermoelectric power (the Seebeck coefficient) and electrical resistivity of undoped single crystals of SnTe under applied high pressure up to 9 GPa, i.e., across the above phase transition. We establish that the high-pressure polymorph of SnTe is a p-type semiconductor and estimate its bandgap value at 3 GPa as Eg ∼ 65 meV. In contrast to the NaCl-type phase, the orthorhombic phase is stable in a much wider pressure range up to about 20 GPa, and its energy gap only insignificantly decreases with pressure with a coefficient of dEg/dP ∼ −4 meV/GPa. We find that the thermoelectric power factor of SnTe can be significantly improved in its orthorhombic phase due to the enhancement of the Seebeck coefficient. Furthermore, we show that the high-pressure phase preserves on the pressure releasing down to 0.3 GPa, and its thermopower grows progressively up to about 100 μV/K due to the bandgap expansion to Eg ∼ 105 meV. This results in a colossal rising of the thermoelectric power factor to about 8 mW/(K2m). Probably, this enhancement is contributed by structural distortions in the orthorhombic phase. We discuss how one could fabricate and optimize the orthorhombic polymorph of SnTe for potential use in various technologies, including thermoelectric applications.
Electron mobility in (100) homoepitaxial layers of phosphorus-doped diamond
Authors: Stenger I. , Pinault-Thaury M.-A. , Temahuki N. , Gillet R. , Temgoua S. , Bensalah H. , Chikoidze E. , Dumont Y. , Barjon J.
Published: March 2021

The electron transport in n-type diamond is investigated using a series of (100) homoepitaxial layers doped with phosphorus in the range of 1016–1018 cm−3. The electrical properties of the n-type layers, such as electron concentration and mobility, were measured using the resistivity and Hall effect as a function of temperature. The scattering of electrons in the diamond was modeled for the (100) orientation, which is preferred for electronic device applications. The physical parameters extracted from the fitting of the experimental data allow us to discuss the upper limit for the electron mobility in (100) n-type diamond.
Comparing (stochastic-selection) ab initio multiple spawning with trajectory surface hopping for the photodynamics of cyclopropanone, fulvene, and dithiane
Authors: Ibele Lea M. , Lassmann Yorick , Martínez Todd J. , Curchod Basile F. E.
Published: March 2021

Ab Initio Multiple Spawning (AIMS) simulates the excited-state dynamics of molecular systems by representing nuclear wavepackets in a basis of coupled traveling Gaussian functions, called trajectory basis functions (TBFs). New TBFs are spawned when nuclear wavepackets enter regions of strong nonadiabaticity, permitting the description of non-Born–Oppenheimer processes. The spawning algorithm is simultaneously the blessing and the curse of the AIMS method: it allows for an accurate description of the transfer of nuclear amplitude between different electronic states, but it also dramatically increases the computational cost of the AIMS dynamics as all TBFs are coupled. Recently, a strategy coined stochastic-selection AIMS (SSAIMS) was devised to limit the ever-growing number of TBFs and tested on simple molecules. In this work, we use the photodynamics of three different molecules—cyclopropanone, fulvene, and 1,2-dithiane—to investigate (i) the potential of SSAIMS to reproduce reference AIMS results for challenging nonadiabatic dynamics, (ii) the compromise achieved by SSAIMS in obtaining accurate results while using the smallest average number of TBFs as possible, and (iii) the performance of SSAIMS in comparison to the mixed quantum/classical method trajectory surface hopping (TSH)—both in terms of its accuracy and computational cost. We show that SSAIMS can accurately reproduce the AIMS results for the three molecules considered at a much cheaper computational cost, often close to that of TSH. We deduce from these tests that an overlap-based criterion for the stochastic-selection process leads to the best agreement with the reference AIMS dynamics for the smallest average number of TBFs.
Three-way symbiotic relationships in whale sharks
Authors: Norman Bradley M. , Reynolds Samantha D. , Morgan David L.
Published: March 2021

Symbiotic relationships between fishes and other organisms are not always easily defined, and three-way symbiotic relationships are rarely reported. Here we examine the relationship between the endangered whale shark, echeneids (remoras and sharksuckers) and a symbiotic copepod. Through their symbiosis with whale sharks, sharksuckers gain one food source from the host’s parasites and energetically-free transportation to foraging areas, where they are also able to feed on the prey targeted by their hosts. The relationship between whale sharks and sharksuckers is complex, and most accurately described as mutualism. Likewise, the whale shark and copepod relationship is also complex, and could be described as a parasitic relationship with commensal or even mutualistic characteristics. Although echeneids are not considered to form host-specific relationships and can be free-ranging, the whale shark copepod occurs only on whale sharks; its survival inextricably linked to that of its host.
Sign surveys can be more efficient and cost effective than driven transects and camera trapping: a comparison of detection methods for a small elusive mammal, the numbat (
Authors: Seidlitz Anke , Bryant Kate A. , Armstrong Nicola J. , Calver Michael C. , Wayne Adrian F.
Published: March 2021

Abstract Context Determining the most efficient detection method for a target species is key for successful wildlife monitoring and management. Driven transects and sign surveys are commonly used to monitor populations of the endangered numbat (Myrmecobius fasciatus). Camera trapping is being explored as a new method. These methods were unevaluated for efficacy and cost for numbat detection. Aims To compare efficacy and costing of driven transects, sign surveys and camera trapping for detecting numbats in the Upper Warren region, Western Australia. Methods Seven repeat sign surveys and driven transects, as well as 4 months of camera trapping, were conducted concurrently at 50 sites along three transects. Numbat detection rates and costing of the three techniques were compared, and detection probabilities were compared between sign surveys and camera trapping. Key results Numbat signs were detected during 88 surveys at 39 sites, exceeding camera trapping (26 detections at 13 sites) and driven transects (seven detections near five sites). The estimated probability for detecting a numbat or a sign thereof (at a site where numbats were present) ranged from 0.21 to 0.35 for a sign survey, and 0.02 to 0.06 for 7 days of camera trapping. Total survey costs were lowest for driven transects, followed by camera trapping and sign surveys. When expressed as cost per numbat detection, sign surveys were cheapest. Conclusions Comparative studies of survey methods are essential for optimal, cost-effective wildlife monitoring. Sign surveys were more successful and cost effective than camera trapping or driven transects for detecting numbats in the Upper Warren region. Together with occupancy modelling, sign surveys are appropriate to investigate changes in occupancy rates over time, which could serve as a metric for long-term numbat monitoring. Implications There is no ‘best’ method for wildlife surveys. Case-specific comparison of animal detection methods is recommended to ensure optimal methods. For the numbat population in the Upper Warren region, further studies are needed to improve numbat detection rates from camera trapping, and to test sign surveys in autumn (March to May), when surviving juvenile numbats have established their own territory and assumptions regarding population closure are less likely to be violated.
Membrane bending by protein phase separation
Authors: Yuan Feng , Alimohamadi Haleh , Bakka Brandon , Trementozzi Andrea N. , Day Kasey J. , Fawzi Nicolas L. , Rangamani Padmini , Stachowiak Jeanne C.
Published: March 2021

Significance

Cellular membranes take on an elaborate set of highly curved and bent shapes which are essential to diverse cellular functions from endocytosis to cell division. The prevailing view has been that membrane bending is driven by proteins with curved shapes, which assemble at the membrane surface to form solid scaffolds. In contrast, here we show that proteins which form liquid-like assemblies on membranes are also potent drivers of bending. These “liquid scaffolds” apply compressive stress to the membrane surface, generating a diverse and dynamic family of membrane shapes. These data, which come at a time when liquid-like protein assemblies are being identified throughout the cell, suggest that protein liquids may play an important role in shaping cellular membranes.
Archaeal Connectase is a specific and efficient protein ligase related to proteasome β subunits
Authors: Fuchs Adrian C. D. , Ammelburg Moritz , Martin Jörg , Schmitz Ruth A. , Hartmann Marcus D. , Lupas Andrei N.
Published: March 2021

Significance

Connectase is an unusual monomeric homolog of proteasome subunits which, unlike all other currently known members of this hydrolase family, is a sequence-specific protein ligase. We identify a natural target for it in a key enzyme of the pathway by which carbon dioxide and hydrogen are converted to methane in archaea. The transpeptidase reaction it catalyzes is highly sequence-specific, allowing it to efficiently ligate proteins that carry the recognition sequence, even in dilute and impure solutions. Connectase ligates substrates at substantially higher rates than other transpeptidases and without detectable side reactions, thus representing a valuable new tool for bioengineering.
Disruption of neonatal Purkinje cell function underlies injury-related learning deficits
Authors: Sathyanesan Aaron , Kratimenos Panagiotis , Gallo Vittorio
Published: March 2021

Significance

Injury to the cerebellum during late fetal and early postnatal life is associated with long-term motor and cognitive deficits. It is thought that injury at this stage of development results in delayed maturation of neural circuitry, causing altered behavior at later stages. This study identifies the neural basis of locomotor learning deficits in the cerebellum using a clinically relevant model of neonatal brain injury. By combining fiber-optic-enabled Purkinje cell activity measurement during locomotor behavior, we provide evidence for long-term changes in neuronal responses during learning. By artificially reducing Purkinje cell function during the neonatal stage, we observed similarly altered physiological responses as those seen in injury. Our findings indicate that injury-related inhibition of developing Purkinje cells causes long-term locomotor dysfunction.
Distinct functional developments of surviving and eliminated presynaptic terminals
Authors: Midorikawa Mitsuharu , Miyata Mariko
Published: March 2021

Significance

During neuronal circuit development, there is a surplus of synapses that undergo selective strengthening or elimination via experience-dependent mechanisms. However, the functional differentiation of presynaptic terminals during the refinement process remains elusive. To address this issue, we performed direct electrophysiological recordings selectively from presynaptic terminals fated for survival or elimination in the somatosensory thalamus during neural circuit refinement. With development, the transmitter release mechanisms matured in an experience-dependent manner at surviving presynaptic terminals but not at those that were later eliminated. However, the maturation of action potential waveforms was indistinguishable between surviving and eliminated terminals. Thus, we clarified a distinct functional development of presynaptic terminals fated for survival and for elimination during neuronal circuit refinement.
Synthetic heparan sulfate standards and machine learning facilitate the development of solid-state nanopore analysis
Authors: Xia Ke , Hagan James T. , Fu Li , Sheetz Brian S. , Bhattacharya Somdatta , Zhang Fuming , Dwyer Jason R. , Linhardt Robert J.
Published: March 2021

Significance

Glycans, proteins, and nucleic acids are the three most important biomolecule classes. Nanopore DNA sequencing is moving toward maturity as a competitive alternative to commonly used technologies. A few nanopore studies have made successful forays into the realm of glycan analysis, motivating the work described in our paper. However, these previous studies have been limited by the absence of highly controlled/well-regulated standards, which now have been chemoenzymatically synthesized by us. Without using amplification, with pioneering solid-state nanopore platform and machine-learning–based signal, we clearly differentiate four synthetic heparan sulfates and, astonishingly, determine disaccharide and even monosaccharide composition on as little as 1 zeptomole of sample.
Quantification ofBrucella abortuspopulation structure in a natural host
Authors: Fiebig Aretha , Vrentas Catherine E. , Le Thien , Huebner Marianne , Boggiatto Paola M. , Olsen Steven C. , Crosson Sean
Published: March 2021

Significance

Understanding microbial population dynamics during infection has important implications for disease management, transmission, and pathogen evolution. A quantitative analysis of microbial population structure requires the ability to track individual strains. We used a pool of individually barcoded strains to measure changes inBrucella abortuspopulation structure during infection of bovine hosts via the ocular conjunctiva, a natural route of entry. Cattle exert a severe bottleneck on the bacterial population entering through the conjunctival mucosa such that individual cells have a 0.0001 probability of colonizing a local draining lymph node. The populations in lymph nodes, even on different sides of the same animal, are distinct and dominated by a small number of highly abundant, spatially distinct clones.
One or two injections of MVA-vectored vaccine shields hACE2 transgenic mice from SARS-CoV-2 upper and lower respiratory tract infection
Authors: Liu Ruikang , Americo Jeffrey L. , Cotter Catherine A. , Earl Patricia L. , Erez Noam , Peng Chen , Moss Bernard
Published: March 2021

Significance

Vaccines are required to control COVID-19 during the current pandemic and possibly afterward. Recombinant nucleic acids, proteins, and virus vectors that stimulate immune responses to the SARS-CoV-2 S protein have provided protection in experimental animal and human clinical trials, although questions remain regarding their ability to prevent spread and the duration of immunity. The present study focuses on replication-restricted modified vaccinia virus Ankara (MVA), which has been shown to be a safe, immunogenic, and stable smallpox vaccine and a promising vaccine vector for other infectious diseases and cancer. In a transgenic mouse model, one or two injections of recombinant MVAs that express modified forms of S inhibited SARS-CoV-2 replication in the upper and lower respiratory tracts and prevented severe disease.
Case Report: Increasing the Frequency of Intramuscular Naltrexone Administration in a High Risk Patient with Opioid use Disorder
Authors: Wright Melissa , De Aquino Joao P. , Bystrak Tamara
Published: March 2021

Background

As the United States faces a national opioid crisis, opioid overdose deaths have significantly risen over the past decade. Patients with opioid use disorder, particularly those who use high-potency synthetic opioids, are at an increased risk of fatal opioid overdose. Alternative dosing strategies for the treatment of opioid use disorder must be considered in high-risk patients to prevent opioid overdose.

Case

One patient with opioid use disorder at high risk for overdose was treated with extended-release (XR) intramuscular (IM) naltrexone initially every 28 days, but was frequently reporting increased cravings during the week prior to the next injection being due. This patient's dose of XR IM naltrexone was then given at an increased dosing frequency of every 21–24 days for three months. Opioid craving suppression was achieved without clinical or laboratory evidence of side effects or hepatotoxicity.

Discussion

In patients with especially high risk of opioid overdose, consideration of novel dosing strategies for continuation of opioid abstinence is necessary. This is the first report demonstrating the short-term safety and efficacy of more frequent dosing of XR IM naltrexone. This case demonstrates that in select high-risk patients, more frequent dosing of XR IM naltrexone may be an effective strategy to reduce opioid cravings.

Informed Consent

The case was reviewed with the Intuition's Privacy Officer who informed the authors that informed consent could not be obtained by the patient's family members due to 38 U.S.C 7332 restrictions on protected information. This manuscript was de-identified and approved by the institution's local privacy officer for publication in accordance with institution policy.
Article Commentary: The Who, the What, and the How: A Description of Strategies and Lessons Learned to Expand Access to Medications for Opioid use Disorder in Rural America
Authors: Cole Evan S. , DiDomenico Ellen , Green Sherri , Heil Susan K. R. , Hilliard Tandrea , Mossburg Sarah E. , Sussman Andrew L. , Warwick Jack , Westfall John M. , Zittleman Linda , Salvador Julie G.
Published: March 2021

Access to treatment for opioid use disorder (OUD) in rural areas within the United States remains a challenge. Providers must complete 8–24 h of training to obtain the Drug Addiction Treatment Act (DATA) 2000 waiver to have the legal authority to prescribe buprenorphine for OUD. Over the last 4 years, we executed five dissemination and implementation grants funded by the Agency for Healthcare Research and Quality to study and address barriers to providing Medications for Opioid Use Disorder Treatment (MOUD), including psychosocial supports, in rural primary care practices in different states. We found that obtaining the DATA 2000 waiver is just one component of meaningful treatment using MOUD, and that the waiver provides a one-time benchmark that often does not address other significant barriers that providers face daily. In this commentary, we summarize our initiatives and the common lessons learned across our grants and offer recommendations on how primary care providers can be better supported to expand access to MOUD in rural America.
Article Commentary: Addiction Psychiatry and Addiction Medicine – Strange Bedfellows or Separated at Birth?
Authors: Balasanova Alëna A. , Ritvo Alexis D. , Yager Joel
Published: March 2021

Substance use disorders (SUDs) are major causes of morbidity and mortality in the United States. SUDs commonly co-occur with other psychiatric and physical illness and often require management by an addiction specialist to comprehensively address patients’ complex needs. The American Board of Medical Specialties (ABMS) offers two pathways leading to addiction subspecialty board certification: addiction psychiatry (American Board of Psychiatry and Neurology) and addiction medicine (American Board of Preventive Medicine). We explore the history of the distinct but overlapping practices of addiction medicine and addiction psychiatry and describe the unique contributions of each field. Specifically, we review skill sets, specialty training, and career outcomes for physicians specializing in the assessment and management of SUDs. We conclude by highlighting collaboration between the two specialties and offer a shared vision for the future of addiction specialty care.
A Rapid-Cycle Assessment Strategy for Understanding the Opioid Overdose Epidemic in Local Communities
Authors: Taubenberger Simone , Spencer Noelle , Chang Judy C. , Paul Nicole , Fabre Shelcie , Jagessar Bhavita , Trimble Daly , Roberto Raisa , Gill Puneet , Hulsey Eric , Arnold Aaron , Hacker Karen
Published: March 2021

Background

Certain communities in the United States experience greater opioid-involved overdose mortality than others. Interventions to stem overdose benefit from contextual understandings of communities’ needs and strengths in addressing the opioid crisis. This project aims to understand multiple stakeholder perspectives on the opioid epidemic in communities disproportionately affected by opioid-involved overdose mortality.

Methods

We performed a rapid-cycle qualitative assessment study utilizing in-depth interviews with community stakeholders and observations of community meetings in eight communities in Allegheny County, Pennsylvania, USA, disproportionately impacted by opioid-involved overdose mortality. Stakeholder categories included: current and past illicit users of opioids; medical and social service providers; emergency medical services; law enforcement; spouse or other family members of illicit users/former users of opioids; government officials; school officials; community members. Content analysis was utilized to identify themes and answer study questions. Regular feedback to stakeholders was provided to support targeted interventions.

Results

We performed semi-structured, in-depth interviews with 130 community stakeholders and 29 community meeting observations in 2018–2019. Participants perceived similar economic and social determinants as origins of the opioid overdose epidemic including lack of economic resources, loss of jobs, transient populations and dilapidated housing. However, they differed in their awareness of and attention to the epidemic. Awareness was dependent on the visibility of opioid use (presence of paraphernalia litter, location of drug users, media coverage, and relationship to users). Overall, there was good knowledge of naloxone for opioid overdose reversal but less knowledge about local syringe services programs. Perceptions of harm reduction efforts were ambivalent.

Conclusions

Members of communities impacted by the opioid epidemic perceived that economic downturn was a major factor in the opioid overdose epidemic. However, the varied beliefs within and between communities suggest that interventions need to be tailored according to the cultural norms of place.
International comparison CCQM-K41.2017, hydrogen sulfide in nitrogen
Authors: Kim D , Kim Y , Lee S , Kang J , Smeulders D , Wu H , Fuko J , Wijk Janneke I T van , Veen Adriaan M H van der , Tshilongo J , Jozela M , Leshabane N , Mphaphuli G , Ntsasa N G , Dias F , Costa C , Konopelko L , Efremova O , Bartlett S , Brewer P , Murugan A
Published: March 2021

Main text

Hydrogen sulfide (H2S) is a poisonous gas which can paralyze the respiratory system, quickly leading to death. It is also a flammable gas, which will ignite explosively when exposed to heat, open flames or oxidizers. For these reasons, hydrogen sulfide is classified as a hazardous material. This comparison is a repeat of the key comparison of the "CCQM-K41 (2005)" and it is intended to compare the capabilities of the preparation and value assignment of gas standard of hydrogen sulfide in nitrogen. The range of the nominal amount-of-substance fractions of the comparison standard is 10 µmol/mol. A set of hydrogen sulfide in nitrogen gas mixtures were prepared by gravimetry and verified with gas chromatography-atomic emission detector (GC-AED) against a KRISS reference cylinder. The gravimetric values of the amount of substance fractions were adopted as key comparison reference values (KCRVs). The results of 9 participants are consistent with their KCRV. Therefore, it is possible for this key comparison to offer a good traceability and a harmonization among the global distribution data of H2S.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Nutation dynamics and multifrequency resonance in a many-body seesaw
Authors: Xu Hong-Ze , Zhang Shun-Yao , Lu Yu-Kai , Guo Guang-Can , Gong Ming
Published: March 2021

The multifrequency resonance has been widely explored in the context of single-particle models, of which the modulating Rabi model has been the most widely investigated. It has been found that with diagonal periodic modulation, steady dynamics can be realized in some well-defined discrete frequencies. These frequencies are independent of off-diagonal couplings. In this work, we generalize this physics to the many-body seesaw realized using the tilted Bose–Hubbard model. We find that the wave function will recover to its initial condition when the modulation frequency is commensurate with the initial energy level spacing between the ground and the first excited levels. The period is determined by the driving frequency and commensurate ratio. In this case, the wave function will be almost exclusively restricted to the lowest two instantaneous energy levels. By projecting the wave function to these two relevant states, the dynamics is exactly the same as that for the spin precession dynamics and nutation dynamics around an oscillating axis. We map out the corresponding phase diagram, and show that, in the low-frequency regime, the state is thermalized, and in the strong modulation limit, the dynamics is determined by the effective Floquet Hamiltonian. The measurement of these dynamics from the mean position and mean momentum in phase space are also discussed. Our results provide new insights into multifrequency resonance in the many-body system.
Excitation cross sections in a collision between two ground-state hydrogen atoms
Authors: Al Atawneh Saed J , Tőkési K
Published: March 2021

We present excitation cross sections in collision between two ground state hydrogen atoms using a four-body classical trajectory Monte Carlo model. Calculations were performed for impact energies in the range between 1.0 keV and 100 keV where the cross sections are highly relevant to the interest of the fusion research. Beside the total excitation cross sections for target and projectile we also present partial excitation cross sections into the 2s and 2p states of the target. The partial excitation cross sections are compared with the previously obtained theoretical and experimental results.
Novel cost-effective approach to produce nano-sized contact openings in an aluminum oxide passivation layer up to 30 nm thick for CIGS solar cells
Authors: Kandybka Iryna , Birant Gizem , de Wild Jessica , Buldu Dilara Gokcen , Kohl Thierry , Thiruvallur Eachambadi Ragha , Brammertz Guy , Manca Jean V , Meuris Marc , Poortmans Jef , Vermang Bart
Published: March 2021

This work presents a novel method of local contact openings formation in an aluminum oxide (Al2O3) rear surface passivation layer by the selenization of the lithium fluoride (LiF) salt on top of the Al2O3 for ultra-thin copper indium gallium (di)selenide (CIGS) solar cells (SCs). This study introduces the potentially cost-effective, fast, industrially viable, and environmentally friendly way to create the nano-sized contact openings with the homogeneous distribution in the thick, i.e. up to 30 nm, Al2O3 passivation layer. The passivation layer is deposited by atomic layer deposition, while the LiF layer is spin-coated. Selenization is done in the H2Se atmosphere and the optimal process parameters are deduced to obtain nano-sized and uniformly allocated openings as confirmed by scanning electron microscopy images. The contact openings were produced in the different thicknesses of the alumina layer from 6 nm to 30 nm. Furthermore, the Al2O3 rear surface passivation layer with the contact openings was implemented into ultra-thin CIGS SC design, and one trial set was produced. We demonstrated that the created openings facilitate the effective current collection through the dielectric Al2O3 layer up to 30 nm thick. However, the upper limit of Al2O3 thickness in which the contact openings can be created by the described method is not established yet. The produced passivated CIGS SCs show increased external quantum efficiency response due to the optical enhancement of the passivated cells. However, the production of SCs on the Al2O3 passivation layer with the openings created by selenization of LiF is not optimized yet.
Electronic and vibrational properties of the high T
c superconductor Bi2Sr2CaCu2O8: an ab initio study
Authors: Yelpo Carla , Faccio Ricardo , Ariosa Daniel , Favre Sofía
Published: March 2021

In this work, ab initio calculations were performed in order to study the vibrational spectra of the Bi2Sr2CaCu2O8 (Bi2212) compound. A structural modulation correction on some atomic positions, producing a distorted structure with lower symmetry, is used for the calculation. We argue that this correction allows to account for an average effect of the incommensurate superstructure, generating a more accurate representation of the real unit cell observed in this compound. A complete and conclusive vibrational assignment is performed, discussing the correspondences with previous experimental and theoretical reports. A brief analysis of the electronic density of states and band structure comparing the tetragonal and distorted unit cell is also included.
Electric control of nearly free electron states and ferromagnetism in the transition-metal dichalcogenides monolayers
Authors: Li Min , Du Er-Wei , Liang Yun-Ye , Shen Yu-Hao , Chen Ju , Ju Weiwei , An Yipeng , Gong Shi-Jing
Published: March 2021

Using the first-principles calculations, we explore the nearly free electron (NFE) states in the transition-metal dichalcogenides MX
2 (M = Mo, W; X = S, Se, Te) monolayers. It is found that both the external electric field and electron (not hole) injection can flexibly tune the energy levels of the NFE states, which can shift down to the Fermi level and result in novel transport properties. In addition, we find that the valley polarization can be induced by both electron and hole doping in MoTe2 monolayer due to the ferromagnetism induced by the charge injection, which, however, is not observed in other five kinds of MX
2 monolayers. We carefully check band structures of all the MX
2 monolayers, and find that the exchange splitting in the top of the valence band and the bottom of conduction band plays the key role in the ferromagnetism. Our researches enrich the electronic, spintronic, and valleytronic properties of MX
2 monolayers.
Monte Carlo-based dosimetric studies of a locally developed 170Tm LDR brachytherapy seed source
Authors: Sahoo Sridhar , Selvam T Palani , Pathan Munir , Saxena S K , Pandey Usha , Kumar Manoj , Kumar Yogendra
Published: March 2021

170Tm is being explored as a source for applications in brachytherapy. Although it has adequate physical properties, such as a short half-life (128.6 d), high specific activity and a mean photon energy of about 66 keV, it has a drawback of low photon yield (only about six photon emissions/100 beta emissions). The objective of this work is to study the dosimetric characteristics of a locally developed 170Tm brachytherapy seed source using the Monte Carlo-based EGSnrc code system. In this study, we calculate the dose rate constant, air-kerma strength, radial dose function, anisotropic function and 2D dose-rate distributions in water. Separate simulations are carried out by considering the photon (gamma and characteristic x-ray) and beta spectra of the source. For regions close to the source (surface of the source < r < 0.4 cm), the dose is solely due to direct dose deposition by beta particles. At larger distances (0.4 cm < r <10 cm), the dose is due to bremsstrahlung photons produced by beta particles and photon emissions. The calculated value of the dose rate constant is 1.217 ± 0.052 cGy h−1U−1. The value of S
k per mCi is 0.029 ± 0.0009 U mCi−1. The contributions of the inherent photon emission and the bremsstrahlung photons to the total S
k are 0.58 and 0.42, respectively.
Analyzing the effect of misalignment on single-filament carbon fiber tensile testing via stereoscopic computer vision imaging
Authors: Love-Baker Cole A , Harrell Timothy M , Brown Kenneth R , Bumgardner Clifton H , Li Xiaodong
Published: March 2021

An understanding of the constitutive properties of carbon fibers (CFs) is critical to the accuracy of high-resolution composite simulations and to the development of CF derived from low-cost alternative precursor materials. Single-fiber tensile testing is a capable tool to measure CF properties and is well suited to research efforts where only a small number of fibers may be available. However, single-fiber tensile tests are challenging to conduct due to the difficulty in handling small diameter fibers (5–15 μm), the brittleness of single fibers, and the required nanoscale/microscale resolution of testing equipment. The accuracy of the measured properties depends on several factors, but a critical factor is fiber misalignment, especially at short gauge lengths. Current standards do not address the effect of tensile specimen misalignment on measured properties. This work presents a robust method of fiber alignment using stereoscopic computer vision that enables users to align fibers vertically for tensile testing to improve the accuracy of resulting mechanical properties. Additionally, an analytical relationship between fiber misalignment angle and measured properties is developed and validated against the experimental results. As a result, new best practices for single-fiber tensile testing of CF are recommended.
Automatic extrinsic self-calibration of mobile LiDAR systems based on planar and spherical features
Authors: Yu Jiayong , Lu Xiushan , Tian Maoyi , Chan Ting On , Chen Chuanfa
Published: March 2021

Inaccurate extrinsic parameters are one of the major errors of a mobile LiDAR system (MLS). As different types of sensors with incommensurable precisions are integrated in an MLS, the extrinsic parameters cannot be easily isolated and estimated, especially in an automatic mode. To address this issue, this paper proposes an automatic extrinsic self-calibration method for an MLS based on planar and spherical features. First, the planar and spherical features are automatically extracted from scanned point cloud data of different strips using the Random Sample Consensus algorithm, and the corresponding features are matched after the extraction. Secondly, a rigorous relationship is established between the direct geo-referencing equation, the extrinsic parameters, and the geometric constraint model. Thirdly, the extrinsic parameters are calibrated by minimizing the sum of the squares of distances from points on the feature surface to the matched reference feature. Four datasets collected by using four types of MLS were used to verify the proposed method. As a result of combining two geometric features into a single self-calibration adjustment, the experimental results show that the proposed method is superior to the conventional plane-based method in terms of the positional accuracy. The standard deviation of the distance between the check features of the four datasets collected by several mobile platforms before (after) extrinsic calibration were 0.051 m (0.024 m), 0.060 m (0.018 m), 0.029 m (0.009 m), and 0.354 m (0.070 m), which demonstrated the high compatibility and practicality of the proposed method.
N-doped reduced graphene oxide-PEDOT nanocomposites for implementation of a flexible wideband antenna for wearable wireless communication applications
Authors: Thanh Tung Tran , Chen Shengjian Jammy , Fumeaux Christophe , Kim TaeYoung , Losic Dusan
Published: March 2021

We report a flexible and highly efficient wideband slot antenna based on a highly conductive composite of poly(3,4-ethylenedioxythiophene) (PEDOT) and N-doped reduced graphene oxide (N-doped rGO) for wearable applications. The high conductivity of this hybrid material with low sheet resistance of 0.56 Ω/square, substantial thickness of 55 μm, and excellent mechanical resilience (<5.5% resistance change after 1000 bending cycles) confirmed this composite to be a suitable antenna conductor. The antenna achieved an estimated conduction efficiency close to 80% over a bandwidth from 3 to 8 GHz. Moreover, the successful operation of a realized antenna prototype has been demonstrated in free space and as part of a wearable camera system. The read range of the system was measured to be 271.2 m, which is 23 m longer than that of the original monopole antennas provided by the supplier. The synergistic effects between the dual conjugated structures of N-doped rGO and PEDOT in a single composite with fine distribution and interfacial interactions are critical to the demonstrated material performance. The N-doped rGO sheet reinforces the mechanical stability whereas the PEDOT functions as additive and/or binder, leading to an improved electrical and mechanical performance compared to that of the graphene and PEDOT alone. This high-performing nanocomposite material meets requirements for antenna design and opens the door for diverse future non-metallic flexible electronic device developments.