bluuebunny/crossref_metadata_2025 huggingface dataset:
Parent Experience of Hypoxic–Ischemic Encephalopathy and Hypothermia: A Call for Trauma Informed Care
Authors: Sagaser Anna , Pilon Betsy , Goeller Annie , Lemmon Monica , Craig Alexa K.
Published: January 2022

Objective Therapeutic hypothermia (TH) is the standard treatment for hypoxic–ischemic encephalopathy (HIE). We surveyed parents of infants treated with TH about their experiences of communication and parental involvement in the neonatal intensive care unit (NICU).

Study Design A 29-question anonymous survey was posted on a parent support (web site:
https://www.hopeforhie.org
) and sent to members via e-mail. Responses from open-ended questions were analyzed using thematic analysis.

Results A total of 165 respondents completed the survey and 108 (66%) infants were treated with TH. 79 (48%) respondents were dissatisfied/neutral regarding the quality of communication in the NICU, whereas 127 (77%) were satisfied/greatly satisfied with the quality of parental involvement in the NICU. Six themes were identified as follows: (1) setting for communication: parents preferred face to face meetings with clinicians; (2) content and clarity of language: parents valued clear language (use of layman's terms) and being explicitly told the medical diagnosis of HIE; (3) immediate and longitudinal emotional support: parents required support from clinicians to process the trauma of the birth experience and hypothermia treatment; (4) clinician time and scheduling: parents valued the ability to join rounds and other major conversations about infant care; (5) valuing the parent role: parents desired being actively involved in rounds, care times, and decision-making; (6) physical presence and touch: parents valued being physically present and touching their baby; this presence was limited by the novel coronavirus disease 2019 (COVID-19)-related restrictions.

Conclusion We highlight stakeholder views on parent involvement and parent–clinician communication in the NICU and note significant overlap with principles of trauma informed care: safety (physical and psychological), trustworthiness and transparency, peer support, collaboration and mutuality, empowerment, and voice and choice. We propose that a greater understanding and implementation of these principles may allow the medical team to more effectively communicate with and involve parents in the care of infants with HIE in the NICU.

Key Points
Photoinduced Organic Reactions by Employing Pyrene Catalysts
Authors: Sekine Kohei , Kuninobu Yoichiro , Shiozuka Akira
Published: January 2022

Pyrene is one of the most attractive polycyclic aromatic hydrocarbons (PAHs) in photochemistry. Based on their redox properties, pyrenes have potential as photosensitizers. In this review, we summarize recent developments in pyrene-catalyzed photoinduced organic reactions occurring via energy transfer or single-electron transfer based on the excited state of the pyrene.

1 Introduction

2 Photolysis Involving N–O Bond Cleavage or Decarboxylation

3 (Cyclo)addition Reactions with Styrenes

4 Transformations via Cleavage of C–F, C–I, C–S and C–N Bonds

5 Reactions Based on Sensitization-Initiated Electron Transfer (SenI­-ET)

6 Miscellaneous Transformations

7 Conclusion
Efficient Synthesis of Isoquinoline Derivatives through Sequential Cyclization–Deoxygenation Reaction of 2-Alkynylbenzaldoximes
Authors: Balalaie Saeed , Ayoubi Mojtaba , Nikbakht Ali , Amiri Kamran , Abbasi Kejani Alireza , Zahedian Tejeneki Hossein
Published: January 2022

We describe a novel, simple, robust, and efficient cyclization/deoxygenation approach for the synthesis of functionalized isoquinoline derivatives. Over the course of continued studies on o-alkynylbenzaldoxime cyclization reactions, the formation of cyclic nitrones through 6-endo-dig cyclization was achieved using silver triflate or bromine as an electrophile, and subsequently, the deoxygenation process was carried out in the presence of CS2 in good to high yields.
Multiple Myeloma Involving Left Hemicranium
Authors: Parthiban Jutty , Udaykumar B. , Peddireddy Sudeendra Reddy , Prakash Balasubramaniam , Kumar Vighnesh Kandha
Published: January 2022

Multiple myeloma (MM) is a malignant neoplasm of bone marrow affecting plasma cells. It is commonly seen as multiple punched-out lesions in the skull bone as a characteristic feature. Its presentation as hemicranial involvement with intracranial extension is rare. A 46-year-old male presented with left side scalp swelling, prominent over parietal region. X-ray showed multiple punched out lesions involving left hemicranium. CT and MRI brain showed intracranial extension of lesion without brain parenchyma invasion. He was treated with biopsy of lesion followed by chemotherapy.
Oncotic (Myxomatous) Aneurysms: A Review of Management
Authors: Peres Carlos Michel Albuquerque , Brito Alyce Castro de , Peres Carlos Henrique Mesquita , Reichl Alfredo Coimbra , Dutra Laila Patricia Fidelis
Published: January 2022

Atrial myxomas are the most common primary cardiac tumors and may manifest with neurological symptoms in ∼ 30% of cases. Cerebral ischemia, aneurysmal formation, and extravascular metastases are mechanisms that lead to these neurological manifestations. Perilesional changes on computed tomography (CT) and magnetic resonance imaging (MRI) may help in the diagnosis of myxomatous aneurysms, which are usually located in the distal middle cerebral artery (MCA) and in the posterior cerebral artery (PCA) circulation territories. Careful resection of the cardiac lesion is essential for preventing embolism. However, treatment of myxomatous aneurysms is controversial due to the limited understanding of the natural history of this condition. Treatment may include clinical observation in asymptomatic patients, surgical resection, endovascular approaches, adjuvant chemotherapy, and low-dose radiation therapy. We present one case of a female patient with myxomatous aneurysm secondary to an atrial myxoma who presented with neurological symptoms and another case of a female patient who developed neurological symptoms after initial surgical treatment of the primary lesion. Lesion growth rate, topography, morphology, and the patient's clinical condition must be considered when choosing a therapeutical method. Further clinical studies are needed to achieve a better understanding and treatment of this disease.
Nickel-Catalyzed Reductive Cross-Coupling of Benzylic Sulfonium Salts with Aryl Iodides
Authors: Wu Fan , Wang Wei , Yao Ken
Published: January 2022

A nickel-catalyzed cross-electrophile coupling of benzylic sulfonium salts with aryl iodides has been developed, providing direct access to diarylalkanes from readily available and stable coupling partners. Preliminary mechanistic studies suggest that the C–S bond cleavage proceeds through a single-electron transfer process to generate a benzylic radical.
Telementoring of Open and Laparoscopic Knot Tying and Suturing Is Possible: A Randomized Controlled Study
Authors: Elrod Julia , Boettcher Johannes , Vincent Deirdre , Schwarz David , Trautmann Tina , Reinshagen Konrad , Boettcher Michael
Published: January 2022

Aim Several motor learning models have been used to teach highly complex procedural skills in medical education. The aim of this randomized controlled trial was to assess the efficiency of telementoring of open and laparoscopic suturing of medical students compared to conventional in-person teaching and training.

Methods After randomization, 23 medical students were assigned to either the telementoring or the in-person training group. Both groups were taught by surgically trained residence with a student–teacher ratio of 1:1 (teacher–student). Open suturing was assessed in a model of congenital diaphragmatic hernia and laparoscopic suturing in a model of bowel anastomosis. All subjects were trained according to the spaced learning concept for 3 hours. Primary end points were time, knot quality, precision, knot strength, and overall knotting performance/competency. Furthermore, we utilized the Surgery Task Load Index to evaluate the cognitive load of both teaching techniques. Students' subjective progress regarding skill acquisitions and acceptance of telementoring was assessed using a nine-item questionnaire.

Results All 23 trainees significantly improved after training in all knot attributes. More than 90% of all subjects reached proficiency in both groups. In-person training and telementoring were similarly practical, and no significant differences regarding speed, knot quality, precision, knot stability, and procedure performance/competency were found. Students perceived no difference in acquisition of factual or applicational knowledge between the two groups. General acceptance of telementoring was moderate in both groups before training, but increased during training in students actually assigned to this group, in comparison to students assigned to conventional teaching.

Conclusion The current study shows that telementoring of open and laparoscopic suturing is an ideal answer to the current coronavirus disease 2019 pandemic, ensuring continuous training. On-site training and telementoring are similarly effective, leading to substantial improvement in proficiency in intracorporeal suturing and knot tying. Likewise, students' subjective progress regarding skill acquisitions and cognitive load does not differ between teaching methods. Skepticism toward telementoring decreases after exposure to this learning method. Given our results, telementoring should be considered a highly effective and resource-saving educational approach even after the current pandemic.
Full automation of research systems for materials science may be on the horizon
Authors: Ikenson Ben
Published: January 2022

Machine learning for hypothesis generation and artificial intelligence for decision-making may close the loop on scientific process
Hiding from the sound hunter
Authors: Lim Alane
Published: January 2022

Device uses simple and easily fabricated design to acoustically cloak objects.
Asymptotic flocking dynamics of a relativistic Cucker–Smale flock under singular communications
Authors: Byeon Junhyeok , Ha Seung-Yeal , Kim Jeongho
Published: January 2022

We study collision avoidance and flocking dynamics for the relativistic Cucker–Smale (RCS) model with a singular communication weight. For a bounded and regular communication weight, RCS particles can exhibit collisions in finite time depending on the geometry of the initial configuration. In contrast, for a singular communication weight, when particles collide, the associated Cucker–Smale vector field becomes unbounded and the standard Cauchy–Lipschitz theory cannot be applied so that existence theory after collisions is problematic. Thus, the collision avoidance problem is directly linked to the global solvability of the singular RCS model and asymptotic flocking dynamics. In this paper, we present sufficient frameworks leading to the nonexistence of finite-time collisions and asymptotic flocking in terms of initial configuration and blow-up rate at the singular point of communication weight.
Dynamical intricacy and average sample complexity for random bundle transformations
Authors: Yang Kexiang , Chen Ercai , Zhou Xiaoyao
Published: January 2022

In this paper, we introduce the notions of random intricacy and average sample complexity of random dynamical systems by using random covers on the basis of the study by Petersen and Wilson [Dyn. Syst. 33, 369–418 (2018)]. We show that their suprema over open random covers are equal to the random topological entropy after taking supremum over open random covers. We establish similar results between random measure-theoretic intricacy and average sample complexity with random measure-theoretic entropy of random dynamical systems.
Impact of edge harmonic oscillations on the divertor heat flux in NSTX
Authors: Gan K. F. , Gray T. K. , Zweben S. J. , Fredrickson E. D. , Maingi R. , Battaglia D. J. , McLean A. G. , Wirth B. D.
Published: January 2022

Previously, edge-localized mode (ELM)-free and inter-ELM divertor peak heat flux reduction induced by an edge harmonic oscillation (EHO) was observed in NSTX [Gan et al., Nucl. Fusion 57, 126053 (2017)]. This paper introduces new analysis of the EHO impact on the divertor heat flux. It was found that enhanced edge turbulence significantly altered the divertor heat flux footprint in NSTX H-modes, relative to ELM-free discharges. When the background edge fluctuation level was low, the EHO significantly increased the heat flux width and decreased the divertor peak heat flux. When the background edge fluctuation level was high, the EHO actually increased the divertor peak heat flux. Furthermore, it was also found that the heat flux width increased with the increasing frequency of the EHO.
Monocrystalline 1.7-eV MgCdTe solar cells
Authors: Ding Jia , Campbell Calli M. , Becker Jacob J. , Tsai Cheng-Ying , Schaefer Stephen T. , McCarthy Tyler T. , Boccard Mathieu , Holman Zachary C. , Zhang Yong-Hang
Published: January 2022

Monocrystalline 1.7 eV Mg0.13Cd0.87Te/MgxCd1−xTe (x > 0.13) double heterostructure (DH) solar cells with varying Mg compositions in the barrier layers are grown by molecular beam epitaxy. A Mg0.13Cd0.87Te/Mg0.37Cd0.63Te DH solar cell featuring abrupt interfaces between barriers and absorber and the addition of a SiO2 anti-reflective coating demonstrate open-circuit voltage (VOC), short-circuit current density (JSC), fill factor (FF), and device active-area efficiencies up to 1.129 V, 17.3 mA/cm2, 77.7%, and 15.2%, respectively. The VOC and FF vary oppositely with the MgxCd1−xTe barrier height, indicating an optimal design of the MgCdTe DHs as a trade-off between carrier confinement and carrier transport. Temperature-dependent VOC measurements reveal that the majority of carrier recombination in the devices occurs outside the DHs, in the a-Si:H hole-contact layer, and at the interface between the a-Si:H layer and the MgxCd1−xTe top barrier at room temperature. Simulation results for the device with the highest efficiency show that the p-type a-Si:H layer and the Mg0.37Cd0.63Te top barrier contribute 1.3 and 2.4 mA/cm2 JSC loss, respectively.
Broadband single-mode planar waveguides in monolithic 4H-SiC
Authors: Bosma Tom , Hendriks Joop , Ghezellou Misagh , Son Nguyen T. , Ul-Hassan Jawad , van der Wal Caspar H.
Published: January 2022

Color-center defects in silicon carbide promise opto-electronic quantum applications in several fields, such as computing, sensing, and communication. In order to scale down and combine these functionalities with the existing silicon device platforms, it is crucial to consider SiC integrated optics. In recent years, many examples of SiC photonic platforms have been shown, like photonic crystal cavities, film-on-insulator waveguides, and micro-ring resonators. However, all these examples rely on separating thin films of SiC from substrate wafers. This introduces significant surface roughness, strain, and defects in the material, which greatly affects the homogeneity of the optical properties of color centers. Here, we present and test a method for fabricating monolithic single-crystal integrated-photonic devices in SiC: tuning optical properties via charge carrier concentration. We fabricated monolithic SiC n-i-n and p-i-n junctions where the intrinsic layer acts as waveguide core, and demonstrate the waveguide functionality for these samples. The propagation losses are below 14 dB/cm. These waveguide types allow for addressing color centers over a broad wavelength range with low strain-induced inhomogeneity of the optical-transition frequencies. Furthermore, we expect that our findings open the road to fabricating waveguides and devices based on p-i-n junctions, which will allow for integrated electrostatic and radio frequency control together with high-intensity optical control of defects in silicon carbide.
Kinetic profiling of therapeutic strategies for inhibiting the formation of amyloid oligomers
Authors: Michaels Thomas C. T. , Dear Alexander J. , Cohen Samuel I. A. , Vendruscolo Michele , Knowles Tuomas P. J.
Published: January 2022

Protein self-assembly into amyloid fibrils underlies several neurodegenerative conditions, including Alzheimer’s and Parkinson’s diseases. It has become apparent that the small oligomers formed during this process constitute neurotoxic molecular species associated with amyloid aggregation. Targeting the formation of oligomers represents, therefore, a possible therapeutic avenue to combat these diseases. However, it remains challenging to establish which microscopic steps should be targeted to suppress most effectively the generation of oligomeric aggregates. Recently, we have developed a kinetic model of oligomer dynamics during amyloid aggregation. Here, we use this approach to derive explicit scaling relationships that reveal how key features of the time evolution of oligomers, including oligomer peak concentration and lifetime, are controlled by the different rate parameters. We discuss the therapeutic implications of our framework by predicting changes in oligomer concentrations when the rates of the individual microscopic events are varied. Our results identify the kinetic parameters that control most effectively the generation of oligomers, thus opening a new path for the systematic rational design of therapeutic strategies against amyloid-related diseases.
Bandgap and electrochemical engineering for disordered LaFeO3
Authors: Sharma Uma , Kailash Veerappan U. K. , Jha Pardeep K. , Jha Priyanka A. , Singh Prabhakar
Published: January 2022

Being a charge transfer Mott insulator with low metal-insulator temperature, disordered LaFeO3 (as an air electrode) is a potential material for electrochemical engineering. High electronic conductivity and inexpensive catalytic activity are the prime requisites for electrode materials. Here, we systematically substituted hole (Sr) at La-site and electron (Ti) at Fe-site. Our objective is here twofold, first to get material with improved catalytic behavior and to understand the role of bandgap engineering. All the investigated samples are oxygen-rich and show orthorhombic(Pbnm) phase at 300 K. The prominent cation vacancies are closely associated with the self-trapping of carriers. These trapping centers may be detrimental if they shift toward conduction band minima. However, this energy shift can be controlled with proper selection of substitution but require intricate understanding. At 300 K, we observe higher conductivity with band shrinkage for hole substitution, i.e., La0.5Sr0.5FeO3 (LSF). A field dependent electrical study reveals trap free conduction for the hole substituted sample while undoped and compensated show ohmic conduction. Our results suggest that there is a correlation between band tuning and corrosion resistance. Dynamic numerical simulation, where interfacial electrochemical behavior up to 4000 s is studied, suggests that LSF has the least surface charge degradation. Experimentally, LSF proves to be a robust and efficient electrode due to chronopotentiometry stability with a potential of 2 V (vs Ag/AgCl) at a higher current of 150 mA/cm2 in neutral media. Further, this study provides concomitant charge dynamics for these samples and the foster mechanism to get better air electrodes.
Influence of donor-to-acceptor ratio on excited-state electron transfer within covalently tethered CdSe/CdTe quantum dot colloidal heterostructures
Authors: McGranahan Caitlin R. , Watson David F.
Published: January 2022

Carbodiimide-mediated coupling chemistry was used to synthesize heterostructures of CdSe and CdTe quantum dots (QDs) with varying ratios of electron-donating CdTe QDs and electron-accepting CdSe QDs. Heterostructures were assembled via the formation of amide bonds between the terminal functional groups of CdTe-adsorbed 4-aminothiophenol (4-ATP) ligands and CdSe-adsorbed N-hydroxysuccinimide (NHS) ligands. The number of charge acceptors on the surfaces of QDs can greatly influence the rate constant of excited-state charge transfer with QDs capable of accommodating far more acceptors than molecular chromophores. We report here on excited-state electron transfer within heterostructure-forming mixtures of 4-ATP-capped CdTe and NHS-capped CdSe QDs with varying molar ratios of CdTe to CdSe. Photophysical properties and charge transfer were characterized using UV–vis absorption, steady-state emission, and time-resolved emission spectroscopy. As the relative concentration of electron-accepting CdSe QDs within mixtures of 4-ATP-capped CdTe and NHS-capped CdSe QDs increased, the rate and efficiency of electron transfer increased by 100-fold and 7.4-fold, respectively, as evidenced by dynamic quenching of band-edge emission from CdTe QDs. In contrast, for non-interacting mixtures of thiophenol capped CdTe QDs and NHS-capped CdSe QDs, which served as control samples, photophysical properties of the constituent QDs were unperturbed and excited-state charge transfer between the QDs was negligible. Our results reveal that carbodiimide-mediated coupling chemistry can be used to control the relative number of donor and acceptor QDs within heterostructures, which, in turn, enables fine-tuning of charge-transfer dynamics and yields. These amide-bridged dual-QD heterostructures are, thus, intriguing for light harvesting, charge transfer, and photocatalysis.
Distinguishing islet amyloid polypeptide fibril structures with infrared isotope-label spectroscopy
Authors: Saxena Vishesh , Steendam Ruben , Jansen Thomas L. C.
Published: January 2022

Here, we performed spectral simulations of the amide-I vibrational spectra for three proposed fibril structures of the human islet amyloid polypeptide, which is involved in type II diabetes. We modeled both the overall absorption and two-dimensional infrared spectra for these structures. We further analyzed the isotope-labeled spectra, including the variation between structures. The analysis suggests that the infrared spectra of the cryo-electron microscopy structure provide the best match with experimental data. We further simulated isotope-labeled dilution spectroscopy investigating the correlation between the predicted spectral peak shift and the coupling between the amide units. While this correlation works in most cases, failures were observed when the isotope-labeled spectra were broad compared to the coupling or exhibited structure. These findings will be useful in the quest for potential toxic fibril formation intermediates.
A connectivity-constrained computational account of topographic organization in primate high-level visual cortex
Authors: Blauch Nicholas M. , Behrmann Marlene , Plaut David C.
Published: January 2022

Inferotemporal (IT) cortex in humans and other primates is topographically organized, containing multiple hierarchically organized areas selective for particular domains, such as faces and scenes. This organization is commonly viewed in terms of evolved domain-specific visual mechanisms. Here, we develop an alternative, domain-general and developmental account of IT cortical organization. The account is instantiated in interactive topographic networks (ITNs), a class of computational models in which a hierarchy of model IT areas, subject to biologically plausible connectivity-based constraints, learns high-level visual representations optimized for multiple domains. We find that minimizing a wiring cost on spatially organized feedforward and lateral connections, alongside realistic constraints on the sign of neuronal connectivity within model IT, results in a hierarchical, topographic organization. This organization replicates a number of key properties of primate IT cortex, including the presence of domain-selective spatial clusters preferentially involved in the representation of faces, objects, and scenes; columnar responses across separate excitatory and inhibitory units; and generic spatial organization whereby the response correlation of pairs of units falls off with their distance. We thus argue that topographic domain selectivity is an emergent property of a visual system optimized to maximize behavioral performance under generic connectivity-based constraints.
Theatrical practices and grammatical standardization in eighteenth-century Britain
Authors: Hyett James , Percy Carol
Published: January 2022

This chapter extends the discussion of second-person pronouns and of eighteenth-century language norms by examining three playwrights’ use of you was in the period before its proscription by grammarians like Robert Lowth (1762). Our analysis corroborates historical sociolinguistic surveys by Tieken-Boon van Ostade (2002) and Laitinen (2009) that identify you was as informal/familiar before 1762. We also show that you was was salient and associated with social lowness in comedies well before it was stigmatized by prescriptivists. Finally, while acknowledging the distinctness of theatrical language, we have identified one useful general property of comedy and especially romantic comedy. The stylized opposition between comic characters (particularly lovers) can signal sociolinguistic salience, here of you was/were by 1747.
Suffixation and sequentiality
Authors: Raymond Chase Wesley
Published: January 2022

This paper offers some reflections on the study of morphology – broadly speaking, ‘word formation’ – as a participants’ resource in social interaction. I begin by calling attention to morphology as a comparatively underexamined component of linguistic structure by conversation analysts and interactional linguists, in that it has yet to receive the same dedicated consideration as have, e.g., phonetics and syntax. I then present an ongoing study of suffixes/suffixation in Spanish – focusing on diminutives (e.g., –ito), augmentatives (e.g., –ote), and superlatives (i.e., –ísimo) – and describe how the sequentiality of interaction can offer analysts profound insight into participants’ orientations to morphological resources. With what I refer to as ‘morphological transformations’ – exemplified here in both same-turn and next-turn positions – interactants sequentially construct and expose morphological complexity as such, locally instantiating its relevance in the service of action. It is argued that a focus on transformations therefore provides analysts with a means to ‘break into’ morphology-based collections. A range of cases are presented to illustrate this methodological approach, before a concluding discussion in which I describe how morphology-focused investigations may intersect with explorations of other interactional phenomena.
Pedagogical Realities of Implementing Task-based Language Teaching
Authors: Erlam Rosemary , Tolosa Constanza
Published: January 2022

This book documents how teachers, working in school foreign language learning contexts and teaching beginner learners of languages other than English, learn about and use tasks. It first presents a pedagogically researched account of how teachers learn about, design and evaluate tasks, after being introduced to TBLT during an in-service programme. The authors then go into classrooms to explore ways in which teachers continue to use tasks, as part of their regular ongoing classroom language programmes, following their in-service education. The book documents how the teachers use tasks to open up opportunities for language learning for students and investigates how teachers understand and position tasks and TBLT as relevant and of value to their teaching contexts. The challenges that teachers face in incorporating TBLT into their practice are also explored. The book suggests how the use of the task as a pedagogic tool may contribute to ongoing understanding about TBLT.
Inonotus obliquus. [Descriptions of Fungi and Bacteria].
Authors: Minter D. W. , Soliman G. S.
Published: January 2022

A description is provided for
Inonotus obliquus
, which forms black circular or irregular brittle charcoal- or clinker-like crusts or conks, breaking out of bark on trunks of living trees, particularly
Betula
species. Some information on its dispersal and transmission and conservation status is given, along with details of its geographical distribution (Greenland, Armenia, China (Shanxi), India (Uttarakhand) Iran, Japan, Kazakhstan (Almaty, East Kazakhstan, Kostanay, West Kazakhstan), Mongolia, Nepal, Russia (Altai Krai, Amur Oblast, Kamchatka Krai, Khanty-Mansi Autonomous Okrug, Krasnoyarsk Krai, Novosibirsk Oblast, Omsk Oblast, Primorsky Krai, Republic of Altai, Sakhalin Oblast, Sverdlovsk Oblast, Tomsk Oblast, Tyumen Oblast, Yamalo-Nenets Autonomous Okrug), Sri Lanka, Uzbekistan, Austria, Belarus, Bulgaria, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Italy, Latvia, Lithuania, Netherlands, Norway, Poland, Romania, Russia (Arkhangelsk Oblast, Bryansk Oblast, Chuvash Republic, Ivanovo Oblast, Kaliningrad Oblast, Kaluga Oblast, Kirov Oblast, Komi Republic, Kostroma Oblast, Kursk Oblast, Leningrad Oblast, Moscow Oblast, Murmansk Oblast, Nizhny Novgorod Oblast, Novgorod Oblast, Orenburg Oblast, Pskov Oblast, Republic of Bashkortostan, Republic of Karelia, Republic of Mordovia, Republic of Tatarstan, Smolensk Oblast, Tula Oblast, Tver Oblast, Udmurt Republic, Ulyanovsk Oblast, Vladimir Oblast, Vologda Oblast, Voronezh Oblast, Yaroslavl Oblast), Slovenia, Spain, Sweden, Ukraine, UK, Canada (Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan, Yukon), USA (Alabama, Alaska, Connecticut, Florida, Idaho, Indiana, Kansas, Kentucky, Louisiana, Maine, Massachusetts, Michigan, Minnesota, Mississippi, Montana, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, Washington, West Virginia, Wisconsin)) and hosts (
Betula
spp. and
Alnus
spp.).
Establishing an equivalent circuit for a quasihomogeneous discharge atmospheric-pressure plasma jet with a breakdown-voltage-controlled breaker and power supply circuit
Authors: Huang Shih-Sen , Tsai Hsing-Che , Chang Jerry , Huang Po-Chun , Cheng Yun-Chien , Wu Jong-Shinn
Published: January 2022

To more accurately simulate the I–V diagram of a homogeneous and a filamentary plasma discharge with an equivalent circuit model, this study employed a breaker and passive circuit components and calculated the discharge parameters, such as equivalent discharge resistances and potential distribution, in an atmospheric pressure plasma jet (APPJ). In addition, we calculated the gas-gap and dielectric capacitances of the APPJ and added a power supply equivalent circuit. Compared with other circuit models that use switches or a time-controlled current source to simulate the discharges, our present circuit model uses a breakdown-voltage-controlled breaker for the homogeneous discharge and resistors with high-frequency switches for the filamentary discharge. We employed potential simulation to obtain the equivalent dielectric capacitance in the APPJ and then derived the gas-gap capacitance. We also replaced the ideal sine wave power supply with the equivalent circuit of the common double-peak waveform power supply. MATLAB Simulink was used to construct an equivalent circuit model and the discharge area ratio, breakdown voltage and filamentary equivalent resistance were obtained via I–V waveform fitting. We measured the plasma I–V waveform with a 20 kHz frequency, various voltages (6, 12 and 15 kV), a gas flow rate of 30 standard liter per minute (SLM) and two types of gas (Ar and He). The simulated and experimental I–V waveforms were very close under the different conditions. In summary, the proposed equivalent circuit model more meaningfully describes the plasma physics to simulate homogeneous and filamentary discharges, achieving results that are compatible with our experimental observations. The findings can help with investigating plasma discharge mechanisms and full-model simulations of plasma.
Integrity monitoring for undifferenced and uncombined PPP under local environmental conditions
Authors: Zhang Jie , Zhao Lin , Yang Fuxin , Li Liang , Liu Xiaosong , Zhang Ruizhe
Published: January 2022

Integrity monitoring of precise point positioning (PPP) can provide tightly guaranteed absolute position error bounds for safety-critical applications. However, a complex local environment makes PPP integrity monitoring much more challenging, such as urban canyons. Significant prone multipaths and low observation redundancy are the main difficulties in the accuracy and reliability of PPP. Therefore, we proposed a solution separation-based integrity monitoring algorithm, which is based on a single and dual frequency undifferenced and uncombined PPP model considering compensation for the multipath error distortion by Gaussian overbounding. Both the static and the kinematic data are utilized to test the proposed algorithm. The results show that the proposed algorithm can produce an adequate protection level (PL) in horizontal and vertical directions. Furthermore, the proposed algorithm can obtain a smoother PL and positioning error in a dynamic local environment, and effectively suppress misleading information.
Tuning optical properties of CsPbBr3 by mixing Nd3+ trivalent lanthanide halide cations for blue light emitting devices
Authors: Padhiar Muhammad Amin , Wang Minqiang , Ji Yongqiang , Yang Zhi , Bhatti Arshad Saleem
Published: January 2022

In recent years, significant progress has been made in the red and green perovskite quantum dots (PQDs) based light-emitting devices. However, a scarcity of blue-emitting devices that are extremely efficient precludes their research and development for optoelectronic applications. Taking advantage of tunable bandgaps of PQDs over the entire visible spectrum, herein we tune optical properties of CSPbBr3 by mixing Nd3+ trivalent lanthanide halide cations for blue light-emitting devices. The CsPbBr3 PQDs doped with Nd3+ trivalent lanthanide halide cations emitted strong photoemission from green into the blue region. By adjusting their doping concentration, a tunable wavelength from (515 nm) to (450 nm) was achieved with FWHM from (37.83 nm) to (16.6 nm). We simultaneously observed PL linewidth broadening thermal quenching of PL and the blue shift of the optical bandgap from temperature-dependent PL studies. The Nd3+ cations into CsPbBr3 PQDs more efficiently reduced non-radiative recombination. As a result of the efficient removal of defects from PQDs, the photoluminescence quantum yield (PLQY) has been significantly increased to 91% in the blue-emitting region. Significantly, Nd3+ PQDs exhibit excellent long-term stability against the external environment, including water, temperature, and ultraviolet light irradiation. Moreover, we successfully transformed Nd3+ doped PQDs into highly fluorescent nanocomposites. Incorporating these findings, we fabricate and test a stable blue light-emitting LED with EL emission at (462 nm), (475 nm), and successfully produce white light emission from Nd3+ doped nanocomposites with a CIE at (0.32, 0.34), respectively. The findings imply that low-cost Nd3+ doped perovskites may be attractive as light converters in LCDs with a broad color gamut.
Fetal dose from proton pencil beam scanning craniospinal irradiation during pregnancy: a Monte Carlo study
Authors: Yeom Yeon Soo , Griffin Keith T , Mille Matthew M , Lee Choonik , O’Reilly Shannon , Dong Lei , Jung Jae Won , Lee Choonsik
Published: January 2022

Objective. We conducted a Monte Carlo study to comprehensively investigate the fetal dose resulting from proton pencil beam scanning (PBS) craniospinal irradiation (CSI) during pregnancy. Approach. The gestational-age dependent pregnant phantom series developed at the University of Florida (UF) were converted into DICOM-RT format (CT images and structures) and imported into a treatment planning system (TPS) (Eclipse v15.6) commissioned to a IBA PBS nozzle. A proton PBS CSI plan (prescribed dose: 36 Gy) was created on the phantoms. The TOPAS MC code was used to simulate the proton PBS CSI on the phantoms, for which MC beam properties at the nozzle exit (spot size, spot divergence, mean energy, and energy spread) were matched to IBA PBS nozzle beam measurement data. We calculated mean absorbed doses for 28 organs and tissues and whole body of the fetus at eight gestational ages (8, 10, 15, 20, 25, 30, 35, and 38 weeks). For contextual purposes, the fetal organ/tissue doses from the treatment planning CT scan of the mother’s head and torso were estimated using the National Cancer Institute dosimetry system for CT (NCICT, Version 3) considering a low-dose CT protocol (CTDIvol: 8.97 mGy). Main results. The majority of the fetal organ/tissue doses from the proton PBS CSI treatment fell within a range of 3–6 mGy. The fetal organ/tissue doses for the 38 week phantom showed the largest variation with the doses ranging from 2.9 mGy (adrenals) to 8.2 mGy (eye lenses) while the smallest variation ranging from 3.2 mGy (oesophagus) to 4.4 mGy (brain) was observed for the doses for the 20 week phantom. The fetal whole-body dose ranged from 3.7 mGy (25 weeks) to 5.8 mGy (8 weeks). Most of the fetal doses from the planning CT scan fell within a range of 7–13 mGy, approximately 2-to-9 times lower than the fetal dose equivalents of the proton PBS CSI treatment (assuming a quality factor of 7). Significance. The fetal organ/tissue doses observed in the present work will be useful for one of the first clinically informative predictions on the magnitude of fetal dose during proton PBS CSI during pregnancy.
A novel range telescope concept for proton CT
Authors: Granado-González M , Jesús-Valls C , Lux T , Price T , Sánchez F
Published: January 2022

Proton beam therapy can potentially offer improved treatment for cancers of the head and neck and in paediatric patients. There has been a sharp uptake of proton beam therapy in recent years as improved delivery techniques and patient benefits are observed. However, treatments are currently planned using conventional x-ray CT images due to the absence of devices able to perform high quality proton computed tomography (pCT) under realistic clinical conditions. A new plastic-scintillator-based range telescope concept, named ASTRA, is proposed here to measure the proton’s energy loss in a pCT system. Simulations conducted using GEANT4 yield an expected energy resolution of 0.7%. If calorimetric information is used the energy resolution could be further improved to about 0.5%. In addition, the ability of ASTRA to track multiple protons simultaneously is presented. Due to its fast components, ASTRA is expected to reach unprecedented data collection rates, similar to 108 protons/s. The performance of ASTRA has also been tested by simulating the imaging of phantoms. The results show excellent image contrast and relative stopping power reconstruction.
Impact of in situ NH3 pre-treatment of LPCVD SiN passivation on GaN HEMT performance
Authors: Chen Ding-Yuan , Persson Axel R , Wen Kai-Hsin , Sommer Daniel , Grünenpütt Jan , Blanck Hervé , Thorsell Mattias , Kordina Olof , Darakchieva Vanya , Persson Per O Å , Chen Jr-Tai , Rorsman Niklas
Published: January 2022

The impact on the performance of GaN high electron mobility transistors (HEMTs) of in situ ammonia (NH3) pre-treatment prior to the deposition of silicon nitride (SiN) passivation with low-pressure chemical vapor deposition (LPCVD ) is investigated. Three different NH3 pre-treatment durations (0, 3, and 10 min) were compared in terms of interface properties and device performance. A reduction of oxygen (O) at the interface between SiN and epi-structure is detected by scanning transmission electron microscopy (STEM )-electron energy loss spectroscopy (EELS) measurements in the sample subjected to 10 min of pre-treatment. The samples subjected to NH3 pre-treatment show a reduced surface-related current dispersion of 9% (compared to 16% for the untreated sample), which is attributed to the reduction of O at the SiN/epi interface. Furthermore, NH3 pre-treatment for 10 min significantly improves the current dispersion uniformity from 14.5% to 1.9%. The reduced trapping effects result in a high output power of 3.4 W mm−1 at 3 GHz (compared to 2.6 W mm−1 for the untreated sample). These results demonstrate that the in situ NH3 pre-treatment before LPCVD of SiN passivation is critical and can effectively improves the large-signal microwave performance of GaN HEMTs.
Twist-angle two-dimensional superlattices and their application in (opto)electronics
Authors: Xin Kaiyao , Wang Xingang , Grove-Rasmussen Kasper , Wei Zhongming
Published: January 2022

Twist-angle two-dimensional systems, such as twisted bilayer graphene, twisted bilayer transition metal dichalcogenides, twisted bilayer phosphorene and their multilayer van der Waals heterostructures, exhibit novel and tunable properties due to the formation of Moiré superlattice and modulated Moiré bands. The review presents a brief venation on the development of “twistronics” and subsequent applications based on band engineering by twisting. Theoretical predictions followed by experimental realization of magic-angle bilayer graphene ignited the flame of investigation on the new freedom degree, twist-angle, to adjust (opto)electrical behaviors. Then, the merging of Dirac cones and the presence of flat bands gave rise to enhanced light-matter interaction and gate-dependent electrical phases, respectively, leading to applications in photodetectors and superconductor electronic devices. At the same time, the increasing amount of theoretical simulation on extended twisted 2D materials like TMDs and BPs called for further experimental verification. Finally, recently discovered properties in twisted bilayer h-BN evidenced h-BN could be an ideal candidate for dielectric and ferroelectric devices. Hence, both the predictions and confirmed properties imply twist-angle two-dimensional superlattice is a group of promising candidates for next-generation (opto)electronics.
A 58-dBΩ 20-Gb/s inverter-based cascode transimpedance amplifier for optical communications
Authors: Pan Quan , Luo Xiongshi
Published: January 2022

This work presents a high-gain broadband inverter-based cascode transimpedance amplifier fabricated in a 65-nm CMOS process. Multiple bandwidth enhancement techniques, including input bonding wire, input series on-chip inductive peaking and negative capacitance compensation, are adopted to overcome the large off-chip photodiode capacitive loading and the miller capacitance of the input device, achieving an overall bandwidth enhancement ratio of 8.5. The electrical measurement shows TIA achieves 58 dBΩ up to 12.7 GHz with a 180-fF off-chip photodetector. The optical measurement demonstrates a clear open eye of 20 Gb/s. The TIA dissipates 4 mW from a 1.2-V supply voltage.
Investigation on the passivation, band alignment, gate charge, and mobility degradation of the Ge MOSFET with a GeO
x
/Al2O3 gate stack by ozone oxidation
Authors: Zhou Lixing , Xiang Jinjuan , Wang Xiaolei , Wang Wenwu
Published: January 2022

Ge has been an alternative channel material for the performance enhancement of complementary metal–oxide–semiconductor (CMOS) technology applications because of its high carrier mobility and superior compatibility with Si CMOS technology. The gate structure plays a key role on the electrical property. In this paper, the property of Ge MOSFET with Al2O3/GeO
x
/Ge stack by ozone oxidation is reviewed. The GeO
x
passivation mechanism by ozone oxidation and band alignment of Al2O3/GeO
x
/Ge stack is described. In addition, the charge distribution in the gate stack and remote Coulomb scattering on carrier mobility is also presented. The surface passivation is mainly attributed to the high oxidation state of Ge. The energy band alignment is well explained by the gap state theory. The charge distribution is quantitatively characterized and it is found that the gate charges make a great degradation on carrier mobility. These investigations help to provide an impressive understanding and a possible instructive method to improve the performance of Ge devices.
Investigations of plasma response associated with resonant magnetic perturbation fields using perturbation method in KSTAR H-mode plasmas
Authors: Xiao W.W. , Evans T.E. , Tynan G.R. , Orlov D.M. , Yoon S.W. , Ko W.H. , Kim M.W. , Jeon Y.M. , Nam Y.U. , Oh Y.K. , KSTAR Team
Published: January 2022

The plasma response associated with the resonant magnetic perturbation (RMP) field was investigated using the small edge perturbations induced by a modulated supersonic molecular beam injection (SMBI) in KSTAR. The modulated SMBI provides a time-varying perturbation of the plasma density source in the region just inside the last closed flux surface and a modulated flow damping rate. Radial propagation of the toroidal rotation perturbation induced by SMBI from the q = 3 surface to the q = 2 surface was observed. Theoretical analysis using the general perturbed equilibrium code of the RMP intensity profiles of the RMP field is consistent with the phase profile of the toroidal rotation perturbation.
Amplified warming induced by large-scale application of water-saving techniques
Authors: Fu Jing , Kang Shaozhong , Zhang Lu , Li Xiaolin , Gentine Pierre , Niu Jun
Published: January 2022

Large-scale agricultural activities can exacerbate global climate change. In the past three decades, over 5 Mha of cultivated land have been equipped with water-saving techniques (WSTs) in Northwest China to cope with water scarcity. However, the effect of WSTs on local climate and its mechanisms are not yet understood. Here, we have quantified the local climatic effect by comparing temperature and humidity at controlled and irrigated sites before and after the large-scale implementation of WST. Results show that the substantial reduction in irrigation water use has led to an average increase of 0.3 °C in growing-season temperature and reduced relative humidity by 2%. Near-surface air temperature responds nonlinearly to percentage area of WST and a threshold value of 40% is found before any noticeable warming effect over the study area. Moreover, it is found that regions with relatively humid climates respond more significantly to WST. This study reveals the mechanism of WST on near-surface climate and highlights the importance of incorporating this feedback into sustainable water management and land-surface models for assessing the impact of irrigated agriculture on regional climate change.
Maxima of log-correlated fields: some recent developments*
Authors: Bailey E C , Keating J P
Published: January 2022

We review recent progress relating to the extreme value statistics of the characteristic polynomials of random matrices associated with the classical compact groups, and of the Riemann zeta-function and other L-functions, in the context of the general theory of logarithmically-correlated Gaussian fields. In particular, we focus on developments related to the conjectures of Fyodorov and Keating concerning the extreme value statistics, moments of moments, connections to Gaussian multiplicative chaos, and explicit formulae derived from the theory of symmetric functions.
Investigation of the confinement of high energy non-neutral proton beam in a bent magnetic mirror
Authors: WANG Fangping , ZHANG Heng , ZHANG Sheng , DUAN Wenshan
Published: January 2022

By using the particle-in-cell (PIC) simulation method, we studied how the proton beam is confined in a bent magnetic mirror. It is found that the loss rate of the charged particles in a bent mirror is less than that in the axi-symmetric mirror. For a special bent mirror with the deflection angle of the coils α = 45°, it is found that the loss rate reaches maximum value at certain ion number density where the ion electrostatic oscillation frequency is equal to the ion cyclotron frequency. In addition, the loss rate is irrelevant to the direction of the proton beam. Our results may be helpful to devise a mirror. In order to obtain the least loss rate, we may choose an appropriate deflection angle, and have to avoid a certain ion number density at which the ion electrostatic oscillation frequency is equal to the ion cyclotron frequency.