bluuebunny/crossref_metadata_2025 huggingface dataset:
A Preliminary Comparison of In-Person and Telepractice Evaluations of Stuttering
Authors: McGill Megann , Siegel Jordan , Noureal Natasha
Published: June 2021

Purpose

The purpose of this study was to compare in-person and telepractice evaluations of stuttering with adult participants. The research questions were as follows: Is an evaluation for stuttering via telepractice equivalent to an in-person evaluation in terms of (a) duration of individual evaluation tasks and overall length of the evaluation, (b) clinical outcomes across evaluating clinicians, and (c) participant experience?

Method

Participants were 14 adults who stutter (males = 11; age range: 20–68) who were simultaneously assessed via telepractice and in-person. Comprehensive evaluations included analysis of the speaker's stuttering, evaluation of the speaker's perceptions and attitudes about stuttering, and language testing. Evaluations were administered by either an in-person clinician or a telepractice clinician but were simultaneously scored by both clinicians. Participants were randomly assigned to the in-person-led assessment condition or the telepractice-led assessment condition.

Results

No statistically significant differences were found between the in-person and telepractice-led evaluations in terms of overall evaluation task duration, evaluation clinical outcomes, or participants' reported experiences. That is, telepractice evaluations for stuttering in adults may be an equivalent option to in-person evaluations.

Conclusions

Results of this preliminary study indicate that telepractice evaluations of stuttering may be comparable to in-person evaluations in terms of duration, clinical outcomes, and participant experiences. The current study supports the notion that telepractice evaluations may be a viable option for adult clients who stutter. Clinical considerations and future directions for research are discussed.
Evaluating the Use of Telepractice to Deliver Pediatric Feeding Assessments
Authors: Raatz Madeline , Ward Elizabeth C. , Marshall Jeanne , Burns Clare L.
Published: June 2021

Purpose

This study aimed to investigate the interrater reliability of pediatric feeding assessments conducted via synchronous (real-time) telepractice. Secondary aims were to investigate parent and clinician satisfaction.

Method

The eating and/or cup drinking skills of 40 children (aged 4 months to 7 years) were simultaneously assessed by one speech-language pathologist (SLP) leading the appointment via telepractice and a second SLP present in the family home. A purpose-designed assessment form was used to assess (a) positioning, (b) development, (c) oral sensorimotor function, (d) prefeeding respiratory status, (e) observation of eating and drinking, (f) parent–child interaction, (g) overall feeding skills, and (h) feeding recommendations. The telepractice SLP completed a postappointment satisfaction questionnaire, and parents completed five questionnaires specifically investigating perceptions of and satisfaction with the telepractice feeding appointment.

Results

Agreement for all assessment components except intraoral examination (palate integrity and tonsils) was > 85%. All appointments were able to be conducted via telepractice, and for 90% of these (
n
= 36), clinicians agreed that telepractice was an effective service delivery method. Parents reported high levels of satisfaction with telepractice, with 76% reporting that the telepractice appointment was similar to a traditional in-person appointment.

Conclusion

Study results demonstrated that synchronous pediatric feeding assessments conducted in family homes via telepractice were feasible, reliable, and acceptable to both clinicians and parents.

Supplemental Material

https://doi.org/10.23641/asha.14700228
Relationship Between Tasked Vocal Effort Levels and Measures of Vocal Intensity
Authors: Hunter Eric J. , Berardi Mark L. , van Mersbergen Miriam
Published: June 2021

Purpose

Patients with voice problems commonly report increased vocal effort, regardless of the underlying pathophysiology. Previous studies investigating vocal effort and voice production have used a range of methods to quantify vocal effort. The goals of the current study were to use the Borg CR100 effort scale to (a) demonstrate the relation between vocal intensity or vocal level (dB) and tasked vocal effort goals and (b) investigate the repeated measure reliability of vocal level at tasked effort level goals.

Method

Three types of speech (automatic, read, and structured spontaneous) were elicited at four vocal effort level goals on the Borg CR100 scale (2, 13, 25, and 50) from 20 participants (10 females and 10 males).

Results

Participants' vocal level reliably changed approximately 5 dB between the elicited effort level goals; this difference was statistically significant and repeatable. Biological females produced a voice with consistently less intensity for a vocal effort level goal compared to biological males.

Conclusions

The results indicate the utility of the Borg CR100 in tracking effort in voice production that is repeatable with respect to vocal level (dB). Future research will investigate other metrics of voice production with the goal of understanding the mechanisms underlying vocal effort and the external environmental influences on the perception of vocal effort.
Frequency-Following Response in Newborns and Infants: A Systematic Review of Acquisition Parameters
Authors: Lemos Fabiana Aparecida , da Silva Nunes Aryelly Dayane , de Souza Evangelista Carolina Karla , Escera Carles , Taveira Karinna Veríssimo Meira , Balen Sheila Andreoli
Published: June 2021

Purpose

The purpose of this study is to characterize parameters used for frequency-following response (FFR) acquisition in children up to 24 months of age through a systematic review.

Method

The study was registered in PROSPERO and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses' recommendations. Search was performed in six databases (LILACS, LIVIVO, PsycINFO, PubMed, Scopus, and Web of Science) and gray literature (Google Scholar, OpenGrey, ProQuest)as well as via manual searches in bibliographic references. Observational studies using speech stimuli to elicit the FFR in infants with normal hearing on the age range from 0 until 24 months were included. No restrictions regarding language and year of publication were applied. Risk of bias was assessed with the Joanna Briggs Institute Critical Appraisal Checklist. Data on stimulus, presentation rate, time window for analysis, number of sweeps, artifact rejection, online filters, stimulated ear, and examination condition were extracted.

Results

Four hundred fifty-nine studies were identified. After removing duplicates and reading titles and abstracts, 15 articles were included. Seven studies were classified as low risk of bias, seven as moderate risk, and one as high risk.

Conclusions

There is a consensus in the use of some acquisition parameters of the FFR with speech stimulus, such as the vertical mounting, the use of alternating polarity, a sampling rate of 20000 Hz, and the /da/ synthesized syllable of 40 ms in duration as the preferred stimulus. Although these parameters show some consensus, the results disclosed lack of a single established protocol for FFR acquisition with speech stimulus in infants in the investigated age range.
Multibeam antenna using cavity‐based waveguide structure with extended hemispherical lens at millimetre wave
Authors: Chauhan Shakti Singh , Dalal Harikesh , Abegaonkar Mahesh P. , Basu Ananjan
Published: June 2021

A multibeam antenna with a single input port using a cavity‐based waveguide structure is implemented. The proposed structure uses a cylindrical cavity and a higher‐order TM21 mode is excited in it. The higher‐order mode is to divide the incoming power in three different directions. The beam in three different directions is confined by using a 3D‐printed extended hemispherical lens integrated at three openings at the cylindrical cavity. The proposed structure has measured an impedance bandwidth of 1.7 GHz from 56.9 to 58.6 GHz. The achieved beam directions for the proposed antenna structure is 0, 87 and 270°. The measured gain of the antenna for each beam directions is better than 12 dBi.
A wideband bandstop filter with two independently controllable equal‐ripple levels
Authors: Chen Hongyu , Wang Xiaolong , Lu Geyu
Published: June 2021

In this letter, a novel wideband bandstop filter with controllable equal‐ripple response is newly presented. The proposed topology consists of two cascaded transmission lines and three open‐circuited stubs, where, one two‐section OS is shunted between two transmission lines, two three‐section OSs are shunted at two output ports, respectively. By using the proposed design approach, both passband and stopband provide controllable equal‐ripple responses independently, where there are five transmission zeros and six reflection zeros in a single period of frequency domain. For demonstration, an experimental BSF centered at 2 GHz with 20‐dB FBW 129.5% and 30‐dB stopband rejection is designed and fabricated. The simulations and measurements agree with the design theory very well.
Cytotoxicity of chlorambucil immobilized on magnetic iron oxide nanoparticles Fe3O4
Authors: Nowak‐Jary Julia , Machnicka Beata , Kozioł Jacek Juliusz
Published: June 2021

Chlorambucil is a nitrogen mustard alkylating agent used for the treatment of various malignant and non‐malignant cancers. The use of the chemotherapeutic is limited by its toxic side effects which precludes the use of optimal doses. It was decided to investigate if the immobilization of chlorambucil on the magnetic nanoparticles Fe3O4 would increase its cytotoxicity toward chosen cancerous cell lines: ‘Jurkat’ and ‘Hut 78’. The drug was attached to the nanoparticles coated with (3‐aminopropyl)triethoxysilane. The obtained nanostructures were characterized using IR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and dynamic light scattering (DLS) technic. Zeta‐potential measurements at various pH were also carried out. The drug release studies showed that chlorambucil is released from the nanoparticles surface very effectively. The cytotoxicity studies demonstrated that chlorambucil immobilized on the magnetic nanoparticles Fe3O4 displays significantly higher cytotoxicity in comparison to its unbound form.
A universal automatic and self‐powered gate driver power supply for normally‐ON SiC JFETs
Authors: Giannakis Andreas , Peftitsis Dimosthenis
Published: June 2021

Normally‐ON silicon carbide junction‐field‐effect transistors have a simple design and exhibit advantageous performance in terms of losses, elevated junction temperatures and high switching frequencies. However, under a loss of power to their gate, normally‐ON junction‐field‐effect transistors are subject to a shoot‐through situation, which might be severe for their survivability. This paper presents a universal concept for an automatic and self‐powered gate driver power supply circuit for normally‐ON silicon carbide junction‐field‐effect transistors employed in high input‐impedance circuits. The power to the gate is supplied during start‐up and steady‐state operations through a mutually coupled inductor with the high input impedance inductor and by employing a typical low‐voltage, power supply circuit. The performance of the proposed automatic and self‐powered gate driver was evaluated on a DC/DC boost converter rated at 6 kW, as well as in a low‐voltage solid‐state DC circuit breaker. From experiments it is shown that using the proposed circuit, the start‐up process requires approximately 350 s, while the steady‐state switching process of the junction‐field‐effect transistor during steady‐state is also shown. Using the proposed circuit in a low‐voltage solid‐state DC breaker, a fault current of 68 A is cleared within 155 s.
Dynamic compensation based feedforward control against output/input disturbance for LCL‐DAB DC–DC converter operated under no backflow power
Authors: Li Xiaoqiang , Li Mingxue , Zhao Hui , Yong Hui , Wu Xiaojie
Published: June 2021

LCL‐type resonant dual‐active‐bridge (LCL‐DAB) DC–DC converters have more significant advantages in eliminating backflow power and achieving higher voltage gain compared with traditional dual active bridge (DAB) DC–DC converters. Therefore, LCL‐DAB DC–DC converters have a broad application prospect in DC micro‐grids, electric vehicles, uninterruptible power supplies etc. Since at this stage only a few researches on LCL‐DAB DC–DC converters have been done, here, the specific system operation region with triple‐phase‐shift (TPS) modulation scheme designed under no backflow power is presented. Furthermore, a dynamic compensation based feedforward control method under no backflow power is proposed, which enables the LCL‐DAB DC–DC converter to operate under no backflow power in wide region and achieve outstanding dynamic performance against output/input disturbance. Finally, the experimental results verify the feasibility and effectiveness of the proposed control method.
Photodissociation of aliphatic PAH derivatives under relevant astrophysical conditions
Authors: Marciniak A. , Joblin C. , Mulas G. , Mundlapati V. Rao , Bonnamy A.
Published: June 2021

Context. The interaction of polycyclic aromatic hydrocarbons (PAHs) with vacuum ultraviolet (VUV) photons triggers the emission of the well-known aromatic infrared bands (AIBs), but other mechanisms, such as fragmentation, can be involved in this interaction. Fragmentation leads to selection effects that favor specific sizes and structures.

Aims. Our aim is to investigate the impact of aliphatic bonds on the VUV photostability of PAH cations in a cryogenic and collisionless environment with conditions applicable for photodissociation regions (PDRs).

Methods. The studied species are derived from pyrene (C16H10) and coronene (C24H12) and contain aliphatic bonds either in the form of methyl or ethyl sidegroups or of superhydrogenation. Their cations are produced by laser desorption ionization and isolated in the cryogenic ion cell of the PIRENEA setup, where they are submitted to VUV photons of 10.5 eV energy over long timescales (~1000 s). The parent and fragment ions are mass-analyzed and their relative intensities are recorded as a function of the irradiation time. The fragmentation cascades are analyzed with a simple kinetics model from which we identify fragmentation pathways and derive fragmentation rates and branching ratios for both the parents and their main fragments.

Results. Aliphatic PAH derivatives are found to have a higher fragmentation rate and a higher carbon to hydrogen loss compared to regular PAHs. On the other hand, the fragmentation of PAHs with alkylated sidegroups forms species with peripheral pentagonal cycles, which can be as stable as, or even more stable than, the bare PAH cations. This stability is quantified for the main ions involved in the fragmentation cascades by the comparison of the fragmentation rates with the photoabsorption rates derived from theoretical photoabsorption cross sections. The most stable species for which there is an effective competition of fragmentation with isomerization and radiative cooling are identified, providing clues on the structures favored in PDRs.

Conclusions. This work supports a scenario in which the evaporation of nanograins with a mixed aliphatic and aromatic composition followed by VUV photoprocessing results in both the production of the carriers of the 3.4 μm AIB by methyl sidegroups and in an abundant source of small hydrocarbons at the border of PDRs. An additional side effect is the efficient formation of stable PAHs that contain some peripheral pentagonal rings. Our experiments also support the role of isomerization processes in PAH photofragmentation, including the H-migration process, which could lead to an additional contribution to the 3.4 μm AIB.
Review of digital technologies in agriculture as a factor that removes the growth limits to human civilization
Authors: Bogomolov Alexander , Nevezhin Victor , Larionova Margarita , Piskun Elena
Published: June 2021

According to Meadows' model, the main factor that determines the limits to the growth of the human civilization is the agricultural sector of the planet, the latter, however, significantly pollutes the environment and togather with other factors contributes much to global warming. A half of all the habitable land is used for agriculture. Unless the efficiency of agriculture is fundamentally improved and the amount of waste generated as a result, is reduced, a global catastrophe may befall in 30–50 years. Whereas agrarian “garbage” may not be just the waste that pollutes the environment, it can decrease the burden on the environment by being the raw material for fertilizers, feed or fuel manufacturing. Modern digital technologies can improve the efficiency of agriculture, organize low-waste or non-waste production and that will enable people to diminish the pollution of the environment and push away the limits to the growth of human civilization. The developed countries are using digital technologies more and more intensively to increase agricultural productivity and, at the same time, reduce both environmental pollution with agricultural waste and disruption of the ecological balance. The digitalization of agricultural business, the use of geoinformation technologies, drones, robots, artificial intelligence and other technologies of the digital society help to push the limits to the growth of human civilization away into the future.
La responsabilité sociale dans la culture de riz bio en Italie
Authors: Pagliarino Elena , Rolfo Secondo , Zoppi Isabella Maria
Published: June 2021

Cet article est axé sur l’expérience d’un groupe de cultivateurs italiens qui utilisent les pratiques et les méthodes de l’agriculture biologique pour la production du riz. Celle-ci représente encore un phénomène de niche concernant un nombre limité de pionniers. En particulier, notre étude s’intéresse à un réseau informel d’une douzaine de cultivateurs qui partagent une proximité d’identité et de processus. On y relève une très forte confiance relationnelle qui côtoie une confiance institutionnelle donnée par le label biologique et les relations avec une société de distribution bio. Notre approche se fonde sur un cas d’étude associant la méthode de la recherche ethnographique par des observations participantes et la réalisation d’entretiens visant à explorer les processus d’apprentissage collectif, le soutien mutuel et l’autorenforcement au sein de ce groupe très hétérogène. Les résultats de ce projet de recherche participative montrent qu’en matière de recherche agronomique et de recommandations politiques, les agriculteurs peuvent tout à fait prendre leurs responsabilités et avoir un poids décisionnel.
High order numerical schemes for transport equations on bounded domains
Authors: Boutin B. , Nguyen T.H.T. , Sylla A. , Tran-Tien S. , Coulombel J.-F.
Published: June 2021

This article is an account of the NABUCO project achieved during the summer camp CEMRACS 2019 devoted to geophysical fluids and gravity flows. The goal is to construct finite difference approximations of the transport equation with nonzero incoming boundary data that achieve the best possible convergence rate in the maximum norm. We construct, implement and analyze the so-called inverse Lax-Wendroff procedure at the incoming boundary. Optimal convergence rates are obtained by combining sharp stability estimates for extrapolation boundary conditions with numerical boundary layer expansions. We illustrate the results with the Lax-Wendroff and O3 schemes.
Behandlung von Patientinnen mit frühem Mammakarzinom: Evidenz, Kontroversen, Konsens – Meinungsbild deutscher Expert*innen zur 17. Internationalen St.-Gallen-Konsensuskonferenz
Authors: Untch Michael , Fasching Peter A. , Brucker Sara Y. , Budach Wilfried , Denkert Carsten , Haidinger Renate , Huober Jens , Jackisch Christian , Janni Wolfgang , Kolberg-Liedtke Cornelia , Krug David , Kühn Thorsten , Loibl Sibylle , Lüftner Diana , Müller Volkmar , Schneeweiss Andreas , Thill Marc , Harbeck Nadia , Thomssen Christoph
Published: June 2021

Die diesjährige 17. St.-Gallen(SG)-Konsensus-Konferenz zur Behandlung von Patientinnen mit frühem Mammakarzinom (SG-BCC) stand unter dem Motto „Customizing local and systemic therapies for women with early breast cancer“ und fokussierte auf die Herausforderung, die Behandlung des frühen Mammakarzinoms zielgerichteter auf die individuelle Krankheitssituation zu adaptieren. Wie schon in den vergangenen Jahren hat auch dieses Jahr eine deutsche Arbeitsgruppe führender Brustkrebsexpert*innen die Ergebnisse der internationalen SG-BCC 2021 vor dem Hintergrund der deutschen Therapieempfehlungen für den Klinikalltag in Deutschland diskutiert. Der Vergleich der SG-Empfehlungen mit den erst kürzlich aktualisierten Therapieempfehlungen der Kommission Mamma der Arbeitsgemeinschaft Gynäkologische Onkologie e. V. (AGO) sowie der S3-Leitlinie ist hilfreich, da sich das SG-BCC-Panel aus Experten unterschiedlicher Länder zusammensetzt, weshalb länderspezifische Besonderheiten in die SG-Empfehlungen einfließen können. Die deutschen Therapieempfehlungen der AGO sowie der S3-Leitlinie basieren auf der aktuellen Evidenz. Gleichwohl muss jede Therapieentscheidung immer einer Nutzen-Risiko-Abwägung für die individuelle Situation unterzogen und mit der Patientin besprochen werden.
Artroscopia do ombro – Criação de um modelo de treinamento acessível
Authors: Dau Leonardo , Almeida Paula Adamo , Milcent Paul André Alain , Rosa Fernando Martins , Kulcheski Alynson Larocca , Stieven Filho Edmar
Published: June 2021

O objetivo do presente trabalho é criar um modelo de treinamento em artroscopia de ombro de baixo custo abaixo de 100 dólares, tornando-o acessível à capacitação prática de estudantes de medicina e residentes. O modelo foi criado utilizando um cano de PVC de 150 mm de diâmetro em 90 graus e um modelo de ombro sintético. O posicionamento das peças foi disposto de forma a simular a posição de decúbito lateral com membro superior em tração, frequente nas artroscopias. Para auxiliar no treinamento, foram demarcados pontos coloridos na glenóide e foi confeccionado um modelo de parte do manguito rotador na porção superior da escápula. Foi possível confeccionar um modelo para treinamento de artroscopia do ombro com um valor abaixo de 100 dólares, de fácil manufatura, que pode ser um auxiliar no treinamento de cirurgiões.
Case Report of 3-Phosphoglycerate Dehydrogenase Deficiency: A Baby with Severe Microcephaly, Psychomotor Delay, and Seizures
Authors: Salleh Hafizah P. H. M. , Hussain Nahin , Rai Birendra
Published: June 2021

This is a case presentation of a patient with microcephaly, severe developmental delay, and refractory seizures who was found to have low levels of serum serine and glycine. Exome sequencing revealed a homozygous mutation in the 3-phosphoglycerate dehydrogenase deficiency (PHGDH) gene at chromosome 1p12. Cerebrospinal fluid (CSF) serine level was subsequently found to be low in keeping with the genetic diagnosis. L-glycine and L-serine supplements were started, which led to improvement in seizure burden. In this rare condition, seizure impact and psychomotor development can improve with supplementation of L-serine and L-glycine; therefore, timely diagnosis is crucial in the management of these patients. Our case also highlighted the role of molecular genetic testing in cases where CSF sampling is difficult, when there are typical clinical features of PHGDH. PHGDH is a rare disorder but should be considered in patients with microcephaly and refractory epilepsy as supplementation with serine may be beneficial.
Age-Related Effects on Right Femoral Bone of Male Wistar Rats: A Morphometric and Biomechanical Study
Authors: Puelker Sheila Martins , Ribeiro de Castro Sonia Regina , de Souza Romeu Rodrigues , Maifrino Laura Beatriz Mesiano , Nucci Ricardo Aparecido Baptista , Sitta Maria do Carmo
Published: June 2021

Introduction Study of the variations of bone characteristics with age in different animal models is important to design musculoskeletal studies. Thus, this study aimed to evaluate the bone mass, dimensions, and biomechanical parameters of the femur in young, middle-aged, and aged Wistar rats.

Materials and Methods Thirty male rats (Rattus norvegicus) were divided in three groups (n = 10 per group)—3-month-old young rats, 12-month-old middle-aged rats, and 18-months-old aged rats. The right femurs were subjected sequentially to morphometric study (bone weight, cortical thickness) and biomechanical tests (maximum resistance strength and bone stiffness).

Results We observed a significant increase in femur histological (cortical thickness) and biomechanical (maximum strength and bone stiffness) parameters with aging when compared with young animals.

Conclusions With the advancing age, the right femoral bone of middle-aged and old animals had greater variations when compared with young animals. However, further studies with the aid of a comparison between right and left femur and other long bones in both male and female rats are needed to corroborate with our findings.
Foreign direct investment along the Belt and Road: A political economy perspective
Authors: Li Jiatao , Van Assche Ari , Li Lee , Qian Gongming
Published: June 2021

In 2013, China launched its ambitious Belt and Road Initiative (BRI), a large portfolio of infrastructure projects across 71 countries intended to link Eurasian markets by rail and sea. The state-led nature of the Initiative combined with its transformative geopolitical implications have conditioned the type of engagement that many governments and firms in host and third countries are willing to take in Chinese-funded BRI projects. Building on two theoretical streams that have originated in international political economy but have received growing attention in international business, varieties of capitalism and geopolitics, this perspective shows how a greater understanding of the institutional and geopolitical context surrounding BRI helps decipher the selection of host-country firms and third-country MNEs in Chinese-funded BRI projects. We portray firm selection in a BRI project as the outcome of a one-tier bargaining game between China and a host country. We show how institutions and geopolitics influence both the legitimacy gap of Chinese SOEs in a host country and the host country’s relative bargaining power, affecting the likelihood that host firms and third-country MNEs are selected in BRI projects. We also discuss the geopolitical jockeying strategies that these firms can adopt to influence the outcome of the bargaining game.
Asymptotics of the largest eigenvalue distribution of the Laguerre unitary ensemble
Authors: Lyu Shulin , Min Chao , Chen Yang
Published: June 2021

We study the probability that all the eigenvalues of n × n Hermitian matrices, from the Laguerre unitary ensemble with the weight xγe−4nx,x∈0,∞,γ>−1, lie in the interval [0, α]. By using previous results for finite n obtained by the ladder operator approach of orthogonal polynomials, we derive the large n asymptotics of the largest eigenvalue distribution function with α ranging from 0 to the soft edge. In addition, at the soft edge, we compute the constant conjectured by Tracy and Widom [Commun. Math. Phys. 159, 151–174 (1994)] and later proved by Deift, Its, and Krasovsky [Commun. Math. Phys. 278, 643–678 (2008)]. Our conclusions are reduced to those of Deift et al. when γ = 0. It should be pointed out that our derivation is straightforward but not rigorous, and hence, the above results are stated as conjectures.
Asymptotic theory for the detection of mixing in anomalous diffusion
Authors: Zhang Kui , Didier Gustavo
Published: June 2021

In this paper, we develop asymptotic theory for the mixing detection methodology proposed by Magdziarz and Weron [Phys. Rev. E 84, 051138 (2011)]. The assumptions cover a broad family of Gaussian stochastic processes, including fractional Gaussian noise and the fractional Ornstein–Uhlenbeck process. We show that the asymptotic distribution and convergence rates of the detection statistic may be, respectively, Gaussian or non-Gaussian and standard or nonstandard depending on the diffusion exponent. The results pave the way for mixing detection based on a single observed sample path and by means of robust hypothesis testing.
Calculation of algebraic entropies of d-PIV and d-PV
Authors: Tan Chengliang , Zhang Jilong
Published: June 2021

In this paper, we describe the singularity patterns of d-PIV in detail and calculate the algebraic entropies of d-PIV and d-PV, which are shown to be both zeros. However, for the discrete equations that are similar with d-PIV, not all algebraic entropies are zeros. An example shows that even if the equation passes the singularity confinement test, it still has a positive algebraic entropy. We also explore the influence of cyclic patterns and anti-confined patterns in the calculation.
New developments of the Gas Research Institute method for the permeability measurement of porous media
Authors: Jannot Yves , Degiovanni Alain , Moyne Christian , Lasseux Didier
Published: June 2021

This work reports on new developments of an unsteady-state method to measure the permeability and porosity of permeable porous materials, extending the so-called Gas Research Institute method beyond its classical use. These extensions allow one to carry out measurements on samples having a cylindrical shape in the case of one- or three-dimensional (or axisymmetric) flows. They rely on the derivation of the quasi-analytical solutions that are required to interpret the experimental data by solving an inverse problem. The only simplifying assumption is that the compressibility of the probing gas can be treated as a constant over the range of pressure variations during measurement. The relevance of the method, together with the validity of this hypothesis, is checked over a wide range of porosity and permeability values through a sensitivity analysis and a comparison with direct numerical simulations of the complete initial boundary value problem. The efficiency of the method is further illustrated with experiments performed on four different porous materials in one-dimension and axisymmetric configurations for permeabilities ranging between 10−14 and 10−19 m2. The potential capability of diagnosing heterogeneous and/or anisotropic materials is highlighted. These new developments open the way for further extensions to samples of arbitrary shapes or partially saturated by a trapped fluid.
Adaptively controlled fast production of defect-free beryllium ion crystals using pulsed laser ablation
Authors: Wu Qiming , Filzinger Melina , Shi Yue , Wang Zhihui , Zhang Jiehang
Published: June 2021

Trapped atomic ions find wide applications ranging from precision measurement to quantum information science and quantum computing. Beryllium ions are widely used due to the light mass and convenient atomic structure of beryllium; however, conventional ion loading from thermal ovens exerts undesirable gas loads for a prolonged duration. Here, we demonstrate a method to rapidly produce pure linear chains of beryllium ions with pulsed laser ablation, serving as a starting point for large-scale quantum information processing. Our method is fast compared to thermal ovens, reduces the gas load to only 10−12 Torr (10−10 Pa) level, yields a short recovery time of a few seconds, and also eliminates the need for a deep ultraviolet laser for photoionization. We also study the loading dynamics, which show non-Poissonian statistics in the presence of sympathetic cooling. In addition, we apply feedback control to obtain defect-free ion chains with desirable lengths.
Percolation-intercropping strategies to prevent dissemination of phytopathogens on plantations
Authors: Rosales Herrera Diana , Ramírez J. E. , Martínez M. I. , Cruz-Suárez H. , Fernández Téllez A. , López-Olguín Jesús F. , Aragón García Agustín
Published: June 2021

Phytophthora is one of the most aggressive and worldwide extended phytopathogens that attack plants and trees. Its effects produce tremendous economical losses in agronomy and forestry since no effective fungicide exists. We propose to combine percolation theory with an intercropping sowing configuration as a non-chemical strategy to minimize the dissemination of the pathogen. In this work, we model a plantation as a square lattice where two types of plants are arranged in alternating columns or diagonals, and Phytophthora zoospores are allowed to propagate to the nearest and next-to-nearest neighboring plants. We determine the percolation threshold for each intercropping configuration as a function of the plant’s susceptibilities and the number of inoculated cells at the beginning of the propagation process. The results are presented as phase diagrams where crop densities that prevent the formation of a spanning cluster of susceptible or diseased plants are indicated. The main result is the existence of susceptibility value combinations for which no spanning cluster is formed even if every cell in the plantation is sowed. This finding can be useful in choosing a configuration and density of plants that minimize damages caused by Phytophthora. We illustrate the application of the phase diagrams with the susceptibilities of three plants with a high commercial value.
Superfluid liquid helium control for the primordial inflation polarization explorer balloon payload
Authors: Kogut A. , Essinger-Hileman T. , Switzer E. , Wollack E. , Fixsen D. , Lowe L. , Mirel P.
Published: June 2021

The Primordial Inflation Polarization Explorer (PIPER) is a stratospheric balloon payload to measure the polarization of the cosmic microwave background. Twin telescopes mounted within an open-aperture bucket dewar couple the sky to bolometric detector arrays. We reduce detector loading and photon noise by cooling the entire optical chain to 1.7 K or colder. A set of fountain-effect pumps sprays superfluid liquid helium onto each optical surface, producing helium flows of 50–100 cm3 s−1 at heights up to 200 cm above the liquid level. We describe the fountain-effect pumps and the cryogenic performance of the PIPER payload during two flights in 2017 and 2019.
Polarized light shows hot gas swirling around a galactic core
Authors: Berkowitz Rachel
Published: June 2021

The images of galaxy Messier 87 provide evidence of magnetic field lines in its innermost region. Those lines likely trace the event horizon of a supermassive black hole.
A European snowstorm is linked to climate change
Authors: Miller Johanna L.
Published: June 2021

Precipitation that fell across the continent came from part of the Arctic Ocean that’s only recently been free of ice.
The air we breathe in a car
Authors: Mathai Varghese
Published: June 2021

Your typical commute hides complex fluid-dynamical pathways of disease transmission. Where you sit and the windows you open could heighten or suppress the risk of airborne infection.
Biosynthesis of fosfomycin in pseudomonads reveals an unexpected enzymatic activity in the metallohydrolase superfamily
Authors: Simon Max A. , Ongpipattanakul Chayanid , Nair Satish K. , van der Donk Wilfred A.
Published: June 2021

Significance

Fosfomycin is an antibiotic used for the treatment of cystitis. Its activity against both gram-positive and gram-negative pathogens has received strong recent interest. The compound is biosynthesized by both pseudomonads and streptomycetes via two different pathways that converge in the last step to form the natural product. This study investigated the biosynthesis of fosfomycin by
Pseudomonas
and revealed an oxidative decarboxylation activity within this pathway. Structural and sequence analysis of the enzyme identified key residues important for its activity and demonstrated its role in the biosynthesis of other phosphonate natural products. This newly characterized protein family expands the chemical space of catalysis by metallohydrolase superfamily enzymes.
ALS-linked PFN1 variants exhibit loss and gain of functions in the context of formin-induced actin polymerization
Authors: Schmidt Eric J. , Funes Salome , McKeon Jeanne E. , Morgan Brittany R. , Boopathy Sivakumar , O’Connor Lauren C. , Bilsel Osman , Massi Francesca , Jégou Antoine , Bosco Daryl A.
Published: June 2021

Significance

Mutations in profilin-1 (PFN1), an actin-binding protein, cause amyotrophic lateral sclerosis (ALS) through an unknown mechanism. Here, we carried out a series of biophysical and cell biological analyses to investigate the effects of ALS-linked mutations on PFN1 function. We found that some moderately misfolded ALS-linked variants bind certain formin proteins with higher affinity and also promote enhanced formin-mediated actin polymerization. Mutation-induced flexibility within actin- and polyproline-binding regions of PFN1 may underlie these phenotypes. However, severe misfolding of PFN1 leads to loss of function with respect to formin-mediated actin polymerization. Our results indicate that ALS-linked PFN1 perturbs actin dynamics, but the mechanism by which this perturbation occurs appears dependent upon the thermodynamic stability of the mutant protein.
Rubus niveus (Mysore raspberry).
Authors: Pollard Kate
Published: June 2021

R. niveus is a highly invasive perennial shrub native to India, China and Southeast Asia. It was introduced around the world through the horticultural trade for its production of sweet tasting fruit and as an ornamental due to the striking red-purple colour of its stems. Nevertheless, cultivated crops were abandoned due to the formation of dense, spiny thickets and many R. niveus plants escaped from cultivation aided by the distribution of seed by birds. Outside of cultivation, R. niveus can outcompete native vegetation, decrease biodiversity and threaten rare endemic species. The success of many Rubus species is linked to the rapid growth of the roots and their ability to reproduce vegetatively. R. niveus has been described as the most invasive weed species on the Galápagos archipelago and declared a noxious weed in the state of Hawaii, USA (Starr et al., 2003).
Pueraria montana var. lobata (kudzu).
Authors: Pasiecznik Nick
Published: June 2021

P. montana, formerly known as P. lobata, is widely known in the USA as 'kudzu' is native to East Asia. However, it does not appear to be a significant problem anywhere except in south-eastern USA where it was extensively planted in the 1930s and 1940s for erosion control. Seed dispersal appears to be minor but vegetative growth in subtropical areas can be substantial, up to 18 m per growing season. It is a climbing vine and kills vegetation by completely smothering it, and it will also entirely cover telegraph poles and buildings if left to itself. Once introduced it is difficult to control, especially in forest and marginal habitats. There are three varieties, although only var. lobata is so far known to be invasive, in the USA.
Cissus verticillata (possum grape vine).
Authors: Rojas-Sandoval Julissa
Published: June 2021

Cissus verticillata is a large, climbing species cultivated as an ornamental and medicinal plant around the world. It is native to Mexico, Central America and the Caribbean. Once established, C. verticillata grows climbing over the top of the canopy and supporting itself by means of coiled tendrils, or scrambling over the ground. It is common to find this species engulfing entire trees. If the plant is cut, the remaining branches and stems can develop aerial roots that will find their way to the ground, regenerating new. C. verticillata is regarded as a weed in areas within and outside its native distribution range. It was reported in the Lower Rio Grande Valley in Texas in 2003 and may pose a potential weed problem in the citrus groves there and in Florida.
Reconstruction, analysis and interpretation of posterior probability distributions of PET images, using the posterior bootstrap
Authors: Filipović Marina , Dautremer Thomas , Comtat Claude , Stute Simon , Barat Éric
Published: June 2021

The uncertainty of reconstructed PET images remains difficult to assess and to interpret for the use in diagnostic and quantification tasks. Here we provide (1) an easy-to-use methodology for uncertainty assessment for almost any Bayesian model in PET reconstruction from single datasets and (2) a detailed analysis and interpretation of produced posterior image distributions. We apply a recent posterior bootstrap framework to the PET image reconstruction inverse problem and obtain simple parallelizable algorithms based on random weights and on existing maximum a posteriori (MAP) (posterior maximum) optimization-based algorithms. Posterior distributions are produced, analyzed and interpreted for several common Bayesian models. Their relationship with the distribution of the MAP image estimate over multiple dataset realizations is exposed. The coverage properties of posterior distributions are validated. More insight is obtained for the interpretation of posterior distributions in order to open the way for including uncertainty information into diagnostic and quantification tasks.
Sub-millimeter precise photon interaction position determination in large monolithic scintillators via convolutional neural network algorithms
Authors: Kawula M , Binder T M , Liprandi S , Viegas R , Parodi K , Thirolf P G
Published: June 2021

In this work, we present the development and application of a convolutional neural network (CNN)-based algorithm to precisely determine the interaction position of γ-quanta in large monolithic scintillators. Those are used as an absorber component of a Compton camera (CC) system under development for ion beam range verification via prompt-gamma imaging. We examined two scintillation crystals: LaBr3:Ce and CeBr3. Each crystal had dimensions of 50.8 mm × 50.8 mm × 30 mm and was coupled to a 64-fold segmented multi-anode photomultiplier tube (PMT) with an 8 × 8 pixel arrangement. We determined the spatial resolution for three photon energies of 662, 1.17 and 1.33 MeV obtained from 2D detector scans with tightly collimated 137Cs and 60Co photon sources. With the new algorithm we achieved a spatial resolution for the CeBr3 crystal below 1.11(8) mm and below 0.98(7) mm for the LaBr3:Ce detector for all investigated energies between 662 keV and 1.33 MeV. We thereby improved the performance by more than a factor of 2.5 compared to the previously used categorical average pattern algorithm, which is a variation of the well-established k-nearest neighbor algorithm. The trained CNN has a low memory footprint and enables the reconstruction of up to 104 events per second with only one GPU. Those improvements are crucial on the way to future clinical in vivo applicability of the CC for ion beam range verification.
Photo-emission signatures of coherence breakdown in Kondo alloys: dynamical mean-field theory approach
Authors: Poudel B , Lacroix C , Zwicknagl G , Burdin S
Published: June 2021

We study the Kondo alloy model on a square lattice using dynamical mean-field theory for Kondo substitution and disorder effects, together with static mean-field approximations. We computed and analyzed photoemission properties as a function of electronic filling n

c
, Kondo impurity concentration x, and strength of Kondo temperature T
K. We provide a complete description of the angle resolved photoemission spectroscopy (ARPES) signals expected in the paramagnetic (PM) Kondo phases. By analyzing the Fermi surface (FS), we observe the Lifshitz-like transition predicted previously for strong T
K at x = n

c
and we discuss the evolution of the dispersion from the dense coherent to the dilute Kondo regimes. At smaller T
K, we find that this transition marking the breakdown of coherence at x = n

c
becomes a crossover. However, we identify another transition at a smaller concentration x
⋆ where the effective mass continuously vanishes. x
⋆ separates the one-branch and the two-branches ARPES dispersions characterizing respectively dilute and dense Kondo PM regimes. The x − T
K phase diagrams are also described, suggesting that the transition at x
⋆ might be experimentally observable since magnetically ordered phases are stabilized at much lower T
K. FS reconstructions in antiferromagnetic and ferromagnetic phases are also discussed.
Probing non-Gaussianities with the high frequency tail of induced gravitational waves
Authors: Atal Vicente , Domènech Guillem
Published: June 2021

We investigate in detail the spectrum of gravitational waves induced by a peaked primordial curvature power spectrum generated in single-field inflationary models. We argue that the f
NL parameter can be inferred by measuring the high frequency spectral tilt of the induced gravitational waves. We also show that the intrinsically non-Gaussian impact of f
NL in ΩGW is to broaden its peak, although at a negligible level in order not to overproduce primordial black holes. We discuss possible degeneracies in the high frequency spectral tilt between f
NL and a general equation of state of the universe w. Finally, we discuss the constraints on the amplitude, peak and slope (or equivalently, f
NL) of the primordial power spectrum by combining current and future gravitational wave experiments with limits on μ distortions from the cosmic microwave background.
Possible hints of sterile neutrinos in recent measurements of the Hubble parameter
Authors: Gelmini Graciela B. , Kusenko Alexander , Takhistov Volodymyr
Published: June 2021

Local Universe observations find a value of the Hubble constant H
0 that is larger than the value inferred from the Cosmic Microwave Background and other early Universe measurements, assuming
known physics and the ΛCDM cosmological model. We show that additional radiation in active neutrinos produced just before Big Bang Nucleosynthesis by an unstable sterile neutrino with mass ms
= O(10) MeV can alleviate this discrepancy. The necessary masses and couplings of the sterile neutrino, assuming it mixes primarily with ντ and/or νμ neutrinos, are within reach of Super-Kamiokande as well as upcoming laboratory experiments such as NA62 and DUNE.
FIMP Dark Matter from Leptogenesis in Fast Expanding Universe
Authors: Chang Zhi-Fang , Chen Zhao-Xuan , Xu Jia-Shu , Han Zhi-Long
Published: June 2021

Within the framework of canonical type-I seesaw, a feebly interacting massive particle (FIMP) χ is introduced as a dark matter candidate. The leptogenesis mechanism and dark matter relic density share a common origin via decays of Majorana neutrinos N. Provided an additional species φ whose energy density red-shifts as ρφ ∝ a
-(4+n), the Hubble expansion rate is larger than the standard scenario, i.e., the Universe expands faster. The consequences of such a fast expanding Universe (FEU) on leptogenesis as well as FIMP dark matter are investigated in detail. We demonstrate a significant impact on the final baryon asymmetry and dark matter abundance due to the existence of φ for the strong washout scenario. While for the weak washout scenario, the effects of FEU are relatively small. We introduce scale factors FL
and F
χ to describe the corresponding effects of FEU. A semi-analytical approach to derive the efficiency factors η
L
and ηχ in FEU is also discussed. The viable parameter space for success thermal leptogenesis and correct FIMP DM relic density is obtained for standard cosmology and FEU. Our results show that it is possible to distinguish different cosmology scenarios for strong washout cases.