bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective Effects of Platelet-rich plasma for in vitro Fertilization of Rats with Ovarian Failure Induced by Cyclophosphamide
Authors: Budak Özcan , Bostancı Mehmet Sühha , Toprak Veysel , Doğanay Songül , Köse Osman
Published: February 2022

Objective Premature ovarian insufficiency (POI) contributes significantly to female infertility. Cyclophosphamide (CYC has adverse effects on folliculogenesis. Platelet-rich plasma (PRP) is an autologous product rich in many growth factors. We evaluated the protective effect of PRP on in vitro fertilization in female rats with CYC-induced ovarian damage.

Methods Twenty-eight adult female Sprague-Dawley rats were randomly divided into four groups. Group 1 (control-sodium chloride 0.9%; 1 mL/kg, single-dose intraperitoneal [IP] injection); group 2 (CYC), 75 mg/kg, single-dose IP injection and sodium chloride 0.9% (1 mL/kg, single-dose IP injection); group 3 CYC plus PRP, CYC (75 mg/kg, single-dose and PRP (200 μl, single-dose) IP injection); and group 4 (PRP, 200 μl, single-dose IP injection).

Results In the comparisons in terms of M1 and M2 oocytes, it was observed that the CYC group presented a significantly lower amount than the control, CYC/PRP, and PRP groups. (for M1, p = 0.000, p = 0.029, p = 0.025; for M2, p = 0.009, p = 0.004, p = 0.000, respectively). The number of fertilized oocytes and two-celled good quality embryos was found to be statistically significant between the CYC and control groups, CYC + PRP and PRP groups (p = 0.009, p = 0.001, p = 0.000 for oocytes, respectively. For embryos; p = 0.016, p = 0.002, p = 0.000).

Conclusion Platelet-rich plasma can protect the ovarian function against damage caused by CYC, and, in addition, it improves oocyte count and the development of embryos as a result of oocyte stimulation during the IVF procedure.
Analysis of the Correlation/Agreement of Maternal–fetal Doppler Parameters in Normal and Growth-Restricted Fetuses
Authors: Pinsuti Ederlei Munhoz , Bruns Rafael Frederico , Kulak Júnior Jaime , Carvalho Newton Sérgio , Nascimento Dênis José , Zamarian Ana Cristina Perez , Araújo Júnior Edward
Published: February 2022

Objective To assess the degree of correlation/agreement of maternal–fetal Doppler parameters between normal and growth-restricted fetuses (fetal growth restriction [FGR]).

Methods The present observational and retrospective study included 274 singleton pregnancies. The following maternal–fetal Doppler parameters were assessed: uterine artery (UAt), umbilical artery (UA), middle cerebral artery (MCA), cerebroplacental ratio (CPR), and umbilical–cerebral ratio (U/C). The assessment of FGR was based on the Figueiras and Gratacós9 criteria. Spearman correlation coefficients were estimated to assess the correlation between resistance (RI) and pulsatility (PI) indices of Doppler parameters. The agreement between two Doppler parameters was assessed by the Kappa coefficient.

Results In total, 502 Doppler examinations were included, and FGR was observed in 19 out of 274 fetuses. A strong correlation was observed between RI and PI of UAt, UA, and MCA in all of the samples (p < 0.001). Of the 502 Doppler examinations, there was agreement between U/C and CPR percentiles for 480 (95.6%) and disagreement for 22 (4.4%), with Kappa coefficient of 0.26, thereby corresponding to weak agreement. Of the 68 cases with estimated fetal weight ≤ 9th percentile (small for gestational age [SGA]), there was agreement between U/C > 1.0 and CPR < 5th percentile in 61 (88.4%) and disagreement in 7 (5.8%) with Kappa coefficient of 0.49, thereby corresponding to moderate agreement.

Conclusion Strong correlation was observed among RI and PI UAt, UA, and MCA Doppler examinations in the present study; however, weak agreement was observed between U/C and CPR in the normal and FGR fetuses. In SGA, U/C and CPR demonstrated moderate agreement.
Implications of autonomous shipping for maritime education and training: the cadet’s perspective
Authors: Bogusławski Krzysztof , Gil Mateusz , Nasur Jan , Wróbel Krzysztof
Published: February 2022

The Industrial Revolution 4.0 has not left the transportation sector behind. All modes of transportation have, to some extent, already been affected, and maritime is the last to join them. Currently available technology makes autonomous merchant ships a possible alternative to conventional, manned vessels with seafarers. This upcoming shift requires the preparation of necessary policies, such as rethinking obsolete training curricula, in relation to a variety of aspects of the industry, including the future of seafaring as a profession. To formulate such policies, the views of professional seafarers and scholars are sometimes solicited, but the opinions of industry entrants are often neglected. However, the latter may also have some interesting views on the future of their profession, which may be relevant to policy-makers. The results of a worldwide survey, conducted using the Computer-Assisted Web Interviewing (CAWI) method, suggest that the future generation of seafarers fears automation less than their mentors. Although they expect their skills to be useful in automation-driven shipping, they also feel that their Maritime Education and Training institutions (MET) are not doing enough to prepare them for the challenges that the future may hold. This may be due to a lack or poor coverage of shipping autonomization issues in MET curricula, which was mentioned by as many as 41.9% of the respondents. This finding advocates for rethinking the curricula of METs and human resources management in the shipping industry of the future.
Tweaking nanoscale structure to tune photoluminescence
Authors: Patrick Chris
Published: February 2022

Layered structure of photonic crystals narrows and shifts the intrinsic photoluminescent emission of nanoporous anodic alumina.
Characterization of self-magnetic pinch radiographic diode performance on RITS-6 at Sandia National Laboratories. II. Coupling between the inductive voltage adder and the SMP load
Authors: Renk T. J. , Oliver B. V. , Kiefer M. L. , Webb T. J. , Leckbee J. J. , Johnston M. D. , Simpson S. , Mazarakis M. G.
Published: February 2022

The self-magnetic pinch (SMP) diode is a type of radiographic diode used to generate an intense electron beam for radiographic applications. At Sandia National Laboratories, SMP was the diode load for the six-cavity radiographic integrated test stand inductive voltage adder (IVA) driver operated in a magnetically insulated transmission line (MITL). The MITL contributes a flow current in addition to the current generated within the diode itself. Extensive experiments with a MITL of 40 Ω load impedance [T. J. Renk et al., Phys. Plasmas 29, 023105 (2022)] indicate that the additional flow current leads to results similar to what might be expected from a conventional high-voltage interface driver, where flow current is not present. However, when the MITL flow impedance was increased to 80 Ω, qualitatively different diode behavior was observed. This includes large retrapping waves suggestive of an initial coupling to low impedance as well as diode current decreasing with time even as the total current does not. A key observation is that the driver generates total current (flow + diode) consistent with the flow impedance of the MITL used. The case is made in this paper that the 80 Ω MITL experiments detailed here can only be understood when the IVA-MITL-SMP diode is considered as a total system. The constraint of fixed total current plus the relatively high flow impedance limits the ability of the diode (whether SMP or other type) to act as an independent load. An unexpected new result is that in tracking the behavior of the electron strike angle on the converter as a function of time, we observed that the conventional cIVx “Radiographic” radiation scaling (where x ∼ 2.2) begins to break down for voltages above 8 MV, and cubic scaling is required to recover accurate angle tracking.
Tension between predicting accurate ground state correlation energies and excitation energies from adiabatic approximations in TDDFT
Authors: Everhart Lucas M. , Derteano Julio A. , Bates Jefferson E.
Published: February 2022

The connection between the adiabatic excitation energy of time-dependent density functional theory and the ground state correlation energy from the adiabatic connection fluctuation–dissipation theorem (ACFDT) is explored in the limiting case of one excited state. An exact expression is derived for any adiabatic Hartree-exchange–correlation kernel that connects the excitation energy and the potential contribution to correlation. The resulting formula is applied to the asymmetric Hubbard dimer, a system where this limit is exact. Results from a hierarchy of approximations to the kernel, including the random phase approximation (RPA) with and without exchange and the adiabatically exact (AE) approximation, are compared to the exact ones. At full coupling, the numerical results indicate a tension between predicting an accurate excitation energy and an accurate potential contribution to correlation. The AE approximation is capable of making accurate predictions of both quantities, but only in parts of the parameter space that classify as weakly correlated, while RPA tends to be unable to accurately predict these properties simultaneously anywhere. For a strongly correlated dimer, the AE approximation greatly overestimates the excitation energy yet continues to yield an accurate ground state correlation energy due to its accurate prediction of the adiabatic connection integrand. If similar trends hold for real systems, the development of correlation kernels will be important for applications of the ACFDT in systems with large potential contributions to correlation.
A note on perturbation-adapted perturbation theory
Authors: Surján Péter R. , Kőhalmi Dóra , Szabados Ágnes
Published: February 2022

The partitioning introduced recently by Knowles [J. Chem. Phys. 156, 011101 (2022)] is analyzed and its connections with the Adams partitioning and the Davidson–Kapuy partitioning are discussed. Davidson’s partitioning is reformulated using the second quantized formalism. A relation is pointed out between the Knowles condition for the many-body perturbation theory zero order Hamiltonian and the CEPA0 equations.
Indirect influence in social networks as an induced percolation phenomenon
Authors: Xie Jiarong , Wang Xiangrong , Feng Ling , Zhao Jin-Hua , Liu Wenyuan , Moreno Yamir , Hu Yanqing
Published: February 2022

Significance

Increasing empirical evidence in diverse social and ecological systems has shown that indirect interactions play a pivotal role in shaping systems’ dynamical behavior. Our empirical study on collaboration networks of scientists further reveals that an indirect effect can dominate over direct influence in behavioral spreading. However, almost all models in existence focus on direct interactions, and the general impact of indirect interactions has not been studied. We propose a new percolation process, termed induced percolation, to characterize indirect interactions and find that indirect interactions raise a plethora of new phenomena, including the wide range of possible phase transitions. Such an indirect mechanism leads to very different spreading outcomes from that of direct influences.
Precision targeting tumor cells using cancer-specific InDel mutations with CRISPR-Cas9
Authors: Kwon Taejoon , Ra Jae Sun , Lee Soyoung , Baek In-Joon , Khim Keon Woo , Lee Eun A , Song Eun Kyung , Otarbayev Daniyar , Jung Woojae , Park Yong Hwan , Wie Minwoo , Bae Juyoung , Cheng Himchan , Park Jun Hong , Kim Namwoo , Seo Yuri , Yun Seongmin , Kim Ha Eun , Moon Hyo Eun , Paek Sun Ha , Park Tae Joo , Park Young Un , Rhee Hwanseok , Choi Jang Hyun , Cho Seung Woo , Myung Kyungjae
Published: February 2022

Significance

The targeted killing of cancer cells without affecting surrounding normal cells is the most desirable approach for cancer therapy; however, it cannot be easily achieved, owing to the shared properties of normal and cancer cells. Using CRISPR-Cas9 targeting multiple cancer-specific mutations, we developed an innovative approach called cancer-specific insertions and deletions attacker that can induce targeted cancer cell death by simultaneous and multiple DNA double-strand breaks. As demonstrated in cell lines, cancer patient–driven cells and xenografts, the concept proposed in this study may become a potential approach for personalized cancer treatments.
Modeling suggests gene editing combined with vaccination could eliminate a persistent disease in livestock
Authors: Petersen Gertje Eta Leony , Buntjer Jaap B. , Hely Fiona S. , Byrne Timothy John , Doeschl-Wilson Andrea
Published: February 2022

Significance

This proof-of-concept modeling study offers quantitative insights into the potential epidemiological benefits of gene-editing technologies and how these may be most effectively implemented to control one of the most harmful pig diseases to date. In the future, the epidemiological benefits will need to be complemented by systematic assessment of economic and technological feasibility to enable balancing these against ethical and societal concerns.
Nanobodies as allosteric modulators of Parkinson’s disease–associated LRRK2
Authors: Singh Ranjan K. , Soliman Ahmed , Guaitoli Giambattista , Störmer Eliza , von Zweydorf Felix , Dal Maso Thomas , Oun Asmaa , Van Rillaer Laura , Schmidt Sven H. , Chatterjee Deep , David Joshua A. , Pardon Els , Schwartz Thomas U. , Knapp Stefan , Kennedy Eileen J. , Steyaert Jan , Herberg Friedrich W. , Kortholt Arjan , Gloeckner Christian Johannes , Versées Wim
Published: February 2022

Significance

Parkinson’s disease (PD) is the second-most common neurodegenerative disorder. Mutations leading to overactivation of LRRK2 are a leading cause of familial PD, and this protein is therefore considered as an appealing target for drug design. Here, we describe the discovery and characterization of a diverse set of LRRK2-targeting nanobodies. A subset of these nanobodies inhibit LRRK2 via a mechanism that differs from the commonly used LRRK2 kinase inhibitors. Importantly, some of these nanobodies selectively inhibit certain LRRK2 activities (Rab phosphorylation) while leaving other activities (autophosphorylation) unaffected. We anticipate that these nanobodies will find multiple applications as research tools and will open up opportunities for the development of new PD diagnostics and therapeutics in parallel to other currently pursued strategies.
Role of ubiquitin-protein ligase UBR5 in the disassembly of mitotic checkpoint complexes
Authors: Kaisari Sharon , Miniowitz-Shemtov Shirly , Sitry-Shevah Danielle , Shomer Pnina , Kozlov Guennadi , Gehring Kalle , Hershko Avram
Published: February 2022

Significance

The mitotic checkpoint system is essential for the prevention of mistakes in the segregation of chromosomes in mitosis. As long as chromosomes are not attached correctly to the mitotic spindle, a mitotic checkpoint complex (MCC) is assembled and inhibits the action of ubiquitin ligase APC/C (anaphase-promoting complex/cyclosome) to initiate anaphase. When the checkpoint is turned off, MCC is disassembled, allowing anaphase initiation. The mechanisms of MCC disassembly have been studied, but the regulation of this process remained obscure. We found that a second ubiquitin ligase, UBR5 (ubiquitin-protein ligase
N
-recognin 5), ubiquitylates MCC components and stimulates the disassembly of MCC from APC/C, as well as the dissociation of a subcomplex of MCC.
Structure-guided engineering of tick evasins for targeting chemokines in inflammatory diseases
Authors: Bhusal Ram Prasad , Aryal Pramod , Devkota Shankar Raj , Pokhrel Rina , Gunzburg Menachem J. , Foster Simon R. , Lim Herman D. , Payne Richard J. , Wilce Matthew C. J. , Stone Martin J.
Published: February 2022

Significance

Inflammatory diseases collectively account for numerous deaths and morbidity worldwide. New treatment approaches are needed. A central feature of inflammatory diseases is the recruitment of leukocytes to the affected tissues, which is stimulated by secreted proteins called chemokines. Effective suppression of leukocyte recruitment could be achieved by simultaneously targeting multiple chemokines, a natural molecular strategy used by tick salivary proteins called evasins. Here, we describe the structural and molecular features of a tick evasin that control its ability to bind and block a limited set of chemokines. By modifying these features, we demonstrate that evasins can be engineered to alter the array of chemokines that they target. Thus, this study establishes a structure-based paradigm for the development of antiinflammatory therapeutics.
CSB-independent, XPC-dependent transcription-coupled repair in
Drosophila
Authors: Deger Nazli , Cao Xuemei , Selby Christopher P. , Gulec Saygin , Kawara Hiroaki , Dewey Evan B. , Wang Li , Yang Yanyan , Archibald Sierra , Selcuk Berkay , Adebali Ogun , Sekelsky Jeff , Sancar Aziz , Liu Zhenxing
Published: February 2022

Significance

We have discovered that
Drosophila
, which does not have the canonical TCR homologs, does nevertheless carry out TCR as efficiently as organisms that do. Furthermore, using the XR-seq and in vivo excision assay we have also shown that both global repair and TCR in
Drosophila
are dependent on the XPC protein and in that regard,
Drosophila
excision repair is more similar to the monocellular eukaryotic yeast repair system than it is to multicellular eukaryotes. Finally, we have generated genome-wide single nucleotide repair maps of
Drosophila
for CPDs, (6-4) photoproducts, and cisplatin-d(GpG) adducts that should be a useful source for investigators working on DNA damage, repair, and mutagenesis in
Drosophila
.
¿A poco así dices?Biased interrogatives with¿A poco (no)…?in Mexican Spanish
Authors: Alamillo Asela Reig
Published: February 2022

This article offers a characterization of the biased polar interrogative with¿a poco (no)?, frequent in Mexican Spanish. This characterization is based on the system proposed bySudo (2013)and shows that Sudo’s two notions of epistemic bias and evidential bias are necessary and sufficient to characterize the conventional non-propositional meaning associated with the three kinds ofa pocoquestions in Mexican Spanish: thea pocopositive polarity question codes a negative epistemic bias and a [+positive] or [+negative] evidential bias; thea poconegative polarity question with inside negation codes a positive epistemic bias and a [+negative] evidential bias; and thea poconegative polarity question with outside negation codes a positive epistemic bias and a [−negative] evidential bias. Lastly, the article discusses to what extent these characterizations are also compatible with the interactional uses of the short questions¿a poco?and¿a poco no?
Glymphatic system clears extracellular tau and protects from tau aggregation and neurodegeneration
Authors: Ishida Kazuhisa , Yamada Kaoru , Nishiyama Risa , Hashimoto Tadafumi , Nishida Itaru , Abe Yoichiro , Yasui Masato , Iwatsubo Takeshi
Published: February 2022

Accumulation of tau has been implicated in various neurodegenerative diseases termed tauopathies. Tau is a microtubule-associated protein but is also actively released into the extracellular fluids including brain interstitial fluid and cerebrospinal fluid (CSF). However, it remains elusive whether clearance of extracellular tau impacts tau-associated neurodegeneration. Here, we show that aquaporin-4 (AQP4), a major driver of the glymphatic clearance system, facilitates the elimination of extracellular tau from the brain to CSF and subsequently to deep cervical lymph nodes. Strikingly, deletion of AQP4 not only elevated tau in CSF but also markedly exacerbated phosphorylated tau deposition and the associated neurodegeneration in the brains of transgenic mice expressing P301S mutant tau. The current study identified the clearance pathway of extracellular tau in the central nervous system, suggesting that glymphatic clearance of extracellular tau is a novel regulatory mechanism whose impairment contributes to tau aggregation and neurodegeneration.
Investigation of the structural and electronic differences between silver and copper doped ceria using the density functional theory
Authors: Righi Giulia , Benedetti Sara , Magri Rita
Published: February 2022

Using the density functional theory (DFT) we have investigated how Ag and Cu atoms, substitutional to Ce, arrange themselves within Ceria (CeO2) and their effect on the ceria lattice, the oxidation states of the metal atoms, and the oxygen vacancy formation energies. Noble metal doped ceria has been proposed in substitution of platinum for a number of catalytic reactions. We have considered single noble metal atoms substituting Ce atoms in the (111) CeO2 surface unit cell, and investigated the thermodynamic stability of few configurations of one, two, and four Ag or Cu atoms in the unit cell. We have found that the noble metal atoms prefer to be located in the cation layer closer to the surface. An interesting result is that Cu causes a strong lattice distortion contrary to Ag. Ag, instead, causes a stronger reduction (oxygen loss) than Cu, since the electrons released in the oxygen vacancy formation are transferred mainly to Ag atoms, whose oxidation state tends towards +1, their preferred one, as found experimentally. In the Cu doped ceria, instead, part of the electrons reduces cerium atoms from +4 to +3 since Cu tends to stay in the +2 oxidation state, its preferred one. When we increase the concentration of Ag and Cu, substituting four Ce atoms, the noble metal atoms prefer to sit closer to each other, forming structural motifs resembling those typical of the Ag2O and CuO oxides.
Mn and Cu codoped Cs2ZnBr4 metal halide with multiexcitonic emission toward anti-counterfeiting
Authors: Wang Meng , Yang Ruoting , Cheng Shanshan , Li Gaoqiang , Jia Mochen , Chen Xu , Wu Di , Li Xinjian , Shi Zhifeng
Published: February 2022

The growing demand for optical anti-counterfeiting technology requires the development of new environmentally-friendly smart materials with single-component, multimodal fluorescence. Herein, Cs2ZnBr4:0.3Mn2+&0.15Cu+, as an efficient multimodal luminescent material with excitation-wavelength-dependent emission is reported. Under 365 nm and 254 nm UV light excitation, Cs2ZnBr4:Mn2+&Cu+ emits mutually independent green light at 525 nm and blue light at 470 nm, which origin from the emission of Mn2+ and the Cu+ enhanced self-trapped excitons of Cs2ZnBr4, respectively. Furthermore, the multiexcitonic emission is applied to anti-counterfeiting applications and information encryption and decryption engineering. This codoped strategy provides a colorful step to expand the new metal halide materials in fluorescent anti-counterfeiting and information encryption and decryption.
Step-by-step gradual domain adaptation for rotating machinery fault diagnosis
Authors: Sun Haoran , Zeng Jia , Wang Yi , Ruan Hulin , Meng Lihua
Published: February 2022

Deep-learning-based fault diagnosis (FD) methods have shown remarkable superiority in the field of fault prognostic and health management (PHM). However, the performance of a deep neural network relies heavily on a substantial labeled training dataset, which is rare in actual industrial scenarios. Moreover, the extracted fault features under different working conditions follow different joint distribution. As a result, a deep model trained under one condition cannot be extended to others. To address the existing problem, this paper proposes a step-by-step gradual domain adaptive neural network to conduct cross-domain FD, which can realize precise alignment between the source domain and the target domain. Firstly, the maximum mean discrepancy is used to perform primary domain adaptation. Furthermore, two classifiers are set up to limit the discrepancy of target domain data in the classification decision. Finally, the exact alignment of class-level features is achieved by category prototype alignment. The extensive experimental results show the superiority and stability of the proposed method when compared with other conventional approaches.
Surface nanostructures on Nb-doped SrTiO3 irradiated with swift heavy ions at grazing incidence
Authors: Ishikawa N , Fujimura Y , Kondo K , Szabo G L , Wilhelm R A , Ogawa H , Taguchi T
Published: February 2022

A single crystal of SrTiO3 doped with 0.5 wt% niobium (Nb-STO) was irradiated with 200 MeV Au32+ ions at grazing incidence to characterize the irradiation-induced hillock chains. Exactly the same hillock chains are observed by using atomic force microscopy (AFM) and scanning electron microscopy (SEM) to study the relation between irradiation-induced change of surface topography and corresponding material property changes. As expected, multiple hillocks as high as 5–6 nm are imaged by AFM observation in tapping mode. It is also found that the regions in between the adjacent hillocks are not depressed, and in many cases they are slightly elevated. Line-like contrasts along the ion paths are found in both AFM phase images and SEM images, indicating the formation of continuous ion tracks in addition to multiple hillocks. Validity of preexisting models for explaining the hillock chain formation is discussed based on the present results. In order to obtain new insights related to the ion track formation, cross-sectional transmission electron microscopy (TEM) observation was performed. The ion tracks in the near-surface region are found to be relatively large, whereas buried ion tracks in the deeper region are relatively small. The results suggest that recrystallization plays an important role in the formation of small ion tracks in the deep region, whereas formation of large ion tracks in the near-surface region is likely due to the absence of recrystallization. TEM images also show shape deformation of ion tracks in the near-surface region, suggesting that material transport towards the surface is the reason for the absence of recrystallization.
Remarkable decrease in lattice thermal conductivity of transition metals borides TiB2 by dimensional reduction
Authors: Li Ding , Hu Yanxiao , Ding Guangqian , Feng Chunbao , Li Dengfeng
Published: February 2022

Two-dimensional transition metals borides Ti
x
B
x
have excellent magnetic and electronic properties and great potential in metal-ion batteries and energy storage. The thermal management is important for the safety and stability in these applications. We investigated the lattice dynamical and thermal transport properties of bulk-TiB2 and its two-dimensional (2D) counterparts based on density functional theory combined with solving phonon Boltzmann transport equation. The Poisson’s ratio of bulk-TiB2 is positive while it changes to negative for monolayer TiB2. We found that dimension reduction can cause the room-temperature in-plane lattice thermal conductivity decrease, which is opposite the trend of MoS2, MoSe2, WSe2 and SnSe. Additionally, the room temperature thermal conductivity of mono-TiB2 is only one sixth of that for bulk-TiB2. It is attributed to the higher Debye temperature and stronger bonding stiffness in bulk-TiB2. The bulk-TiB2 has higher phonon group velocity and weaker anharmonic effect comparing with its 2D counterparts. On the other hand, the room temperature lattice thermal conductivity of mono-Ti2B2 is two times higher than that of mono-TiB2, which is due to three-phonon selection rule caused by the horizontal mirror symmetry.
Learning-based occupational x-ray scatter estimation
Authors: Maul Noah , Roser Philipp , Birkhold Annette , Kowarschik Markus , Zhong Xia , Strobel Norbert , Maier Andreas
Published: February 2022

Objective. During x-ray-guided interventional procedures, the medical staff is exposed to scattered ionizing radiation caused by the patient. To increase the staff’s awareness of the invisible radiation and monitor dose online, computational scatter estimation methods are convenient. However, such methods are usually based on Monte Carlo (MC) simulations, which are inherently computationally expensive. Yet, in the interventional environment, immediate feedback to the personnel is desirable. Approach. In this work, we propose deep neural networks to mitigate the computational effort of MC simulations. Our learning-based models consider detailed models of the (outer) patient shape and (inner) anatomy, additional objects in the room, and the x-ray tube spectrum to cover imaging settings encountered in real interventional settings. We investigate two cases of scatter prediction. First, we employ network architectures to estimate the full three-dimensional (3D) scatter distribution. Second, we investigate the prediction of two-dimensional (2D) intensity projections that facilitate the intra-procedural visualization. Main results. Depending on the dimensionality of the estimated scatter distribution and the network architecture, the mean relative error of each network is in the range of 12% and 14% compared to MC simulations. However, 3D scatter distributions can be estimated within 60 ms and 2D distributions within 15 ms. Significance. Overall, our method is suitable to support the online assessment of scattered ionizing radiation in the interventional environment and can help to lower the occupational radiation risk.
Development of a GPU-accelerated Monte Carlo dose calculation module for nuclear medicine, ARCHER-NM: demonstration for a PET/CT imaging procedure
Authors: Peng Zhao , Lu Yu , Xu Yao , Li Yongzhe , Cheng Bo , Ni Ming , Chen Zhi , Pei Xi , Xie Qiang , Wang Shicun , Xu X George
Published: February 2022

Objective. This paper describes the development and validation of a GPU-accelerated Monte Carlo (MC) dose computing module dedicated to organ dose calculations of individual patients undergoing nuclear medicine (NM) internal radiation exposures involving PET/CT examination. Approach. This new module extends the more-than-10-years-long ARCHER project that developed a GPU-accelerated MC dose engine by adding dedicated NM source-definition features. To validate the code, we compared dose distributions from the point ion source, including 18F, 11C, 15O, and 68Ga, calculated for a water phantom against a well-tested MC code, GATE. To demonstrate the clinical utility and advantage of ARCHER-NM, one set of 18F-FDG PET/CT data for an adult male NM patient is calculated using the new code. Radiosensitive organs in the CT dataset are segmented using a CNN-based tool called DeepViewer. The PET image intensity maps are converted to radioactivity distributions to allow for MC radiation transport dose calculations at the voxel level. The dose rate maps and corresponding statistical uncertainties were calculated at the acquisition time of PET image. Main results. The water-phantom results show excellent agreement, suggesting that the radiation physics module in the new NM code is adequate. The dose rate results of the 18F-FDG PET imaging patient show that ARCHER-NM’s results agree very well with those of the GATE within −2.45% to 2.58% (for a total of 28 organs considered in this study). Most impressively, ARCHER-NM obtains such results in 22 s while it takes GATE about 180 min for the same number of 5 × 108 simulated decay events. Significance. This is the first study presenting GPU-accelerated patient-specific MC internal radiation dose rate calculations for clinically realistic 18F-FDG PET/CT imaging case involving autosegmentation of whole-body PET/CT images. This study suggests that the proposed computing tools—ARCHER-NM— are accurate and fast enough for routine internal dosimetry in NM clinics.
Inter-patient arrhythmia identification method with RR-intervals and convolutional neural networks
Authors: Zhu Wenliang , Ma Gang , Zheng Lesong , Chen Yuhang , Qiu Lishen , Wang Lirong
Published: February 2022

Objective. The arrhythmia identification method based on the U-net has the potential for fast application. The RR-intervals have been proven to improve the performance of single-heartbeat identification methods. However, because both the heartbeats number and location in the input of the U-net are unfixed, the approach based on the U-net cannot use RR-intervals directly. To solve this problem, we proposed a novel method. The proposed method also can identify heartbeats of four classes, including non-ectopic (N), supraventricular ectopic beat (SVEB), ventricular ectopic beat (VEB), and fusion beat (F). Approach. Our method consists of the pre-processing and the two-stage identification framework. In the pre-processing part, we filtered input signals with a band-pass filter and created the auxiliary waveforms by RR-intervals. In the first stage of the framework, we designed a network to handle input signals and auxiliary waveforms. We proposed a masking operation to separate the input signal into two signals according to the result of the network. The first signal contains heartbeats of SVEB and VEB. The second signal includes heartbeats of N and F. The second stage consists of two networks and can further identify the heartbeats of SVEB, VEB, N, and F from these two signals. Main result. We validated our method on the MIT-BIH arrhythmia database with the inter-patient model. For classes N, SVEB, VEB, and F, our approach achieved F1 scores of 98.26, 68.61, 95.99, and 47.75, respectively. Significance. Our method not only can effectively utilize RR intervals but also can identify multiple arrhythmias.
Standard model physics and the digital quantum revolution: thoughts about the interface
Authors: Klco Natalie , Roggero Alessandro , Savage Martin J
Published: February 2022

Advances in isolating, controlling and entangling quantum systems are transforming what was once a curious feature of quantum mechanics into a vehicle for disruptive scientific and technological progress. Pursuing the vision articulated by Feynman, a concerted effort across many areas of research and development is introducing prototypical digital quantum devices into the computing ecosystem available to domain scientists. Through interactions with these early quantum devices, the abstract vision of exploring classically-intractable quantum systems is evolving toward becoming a tangible reality. Beyond catalyzing these technological advances, entanglement is enabling parallel progress as a diagnostic for quantum correlations and as an organizational tool, both guiding improved understanding of quantum many-body systems and quantum field theories defining and emerging from the standard model. From the perspective of three domain science theorists, this article compiles thoughts about the interface on entanglement, complexity, and quantum simulation in an effort to contextualize recent NISQ-era progress with the scientific objectives of nuclear and high-energy physics.
Design and optimization of DTSCR for high-speed I/O ESD protection of on-chip ICs
Authors: Liang Hailian , Yang Yanni , Sun Jun , Liu Junliang , Cao Xiyue , Gu Xiaofeng
Published: February 2022

A gate-assisted and diode-triggered silicon controlled rectifier with the waffle layout (GDTSCR-WL) is proposed and investigated. By designing the waffle layout in the conventional diode-triggered silicon controlled rectifier (DTSCR), the electrostatic discharge (ESD) performance of the GDTSCR-WL can be used to optimize remarkably, especially for the parasitic capacitance, clamping voltage (V
C), and current handling ability. By further introducing the gate-assisted trigger effect, the GDTSCR-WL can discharge the ESD-induced current more quickly. The technology computer aided design (TCAD) simulations and electrical test results indicate that the GDTSCR-WL has extraordinary ESD performance, such as a V
C of 1.24 V, a turn-on resistance of 0.14 Ω, and the large figure of merit of 5.76 mA μm−2, outperforming dual-diode string and DTSCR. Moreover, by adjusting the width W
1 and space W
2 of diode blocks with the waffle layout, the capacitance of the GDTSCR-WL can be continuously decreased from 140 to 92 fF. The optimized GDTSCR-WL with a small capacitance can pass the 8 kV human body model test, providing an efficient and optional solution for high-speed input/output ESD protection of on-chip ICs.
A neural network-informed self-aware deployable structure with application to phased array antennas
Authors: Gillmer Steven R , Silver Mark J , Jeon Sungeun K
Published: February 2022

State of the art radio frequency (RF) arrays are growing larger in pursuit of increased signal-to-noise ratio. In support of this goal, elaborate forms of metrology are being developed to support the increased footprints. This work provides a unique solution to fulfill the metrology requirements of large-scale deployable RF antennas through the implementation of neural network demodulation of fiber optic strain sensors. The fiber optics are patterned with fiber Bragg gratings (FBGs) to encode strain on to back-reflected shifts in the wavelength of incident light. Experiments show the neural network can predict the deformation of a test structure within single millimeters for small amplitude motions. Therefore, the current technique meets the required

λ

/

20

precision needed for large scale deployable RF arrays operating at S-band or longer wavelengths.
Directed motion of liquid crystal skyrmions with oscillating fields
Authors: Duzgun A , Nisoli C , O Reichhardt C J , Reichhardt C
Published: February 2022

Using continuum simulations, we show that under a sinusoidal electric field, liquid crystal skyrmions undergo periodic shape oscillations which produce controlled directed motion. The speed of the skyrmion is non-monotonic in the frequency of the applied field, and exhibits multiple reversals of the motion as a function of changing frequency. We map out the dynamical regime diagram of the forward and reverse motion for two superimposed ac driving frequencies, and show that the reversals and directed motion can occur even when only a single ac driving frequency is present. Using pulsed ac driving, we demonstrate that the motion arises due to an asymmetry in the relaxation times of the skyrmion shape. We discuss the connection between our results and ratchet effects observed in systems without asymmetric substrates.
The low temperature limit of the excitonic Mott density in GaN: an experimental reassessment
Authors: Mallet-Dida Léo , Disseix Pierre , Réveret François , Médard François , Alloing Blandine , Zúñiga-Pérez Jesús , Leymarie Joël
Published: February 2022

The research on GaN lasers aims for a continuous reduction of the lasing threshold. An approach to achieve it consists in exploiting stimulated polariton scattering. This mechanism, and the associated polariton lasers, requires an in-depth knowledge of the GaN excitonic properties, as polaritons result from the coupling of excitons with photons. Under high excitation intensities, exciton states no longer exist due to the Coulomb screening by free carriers; this phenomenon occurs at the so-called Mott density. The aim of this work is to study the bleaching of excitons under a quasi-continuous optical excitation in a bulk GaN sample of high quality through power dependent micro-photoluminescence and time-resolved experiments at 5 K. Time-resolved photoluminescence allows to measure the carrier lifetime as a function of excitation intensity, which is required for a reliable evaluation of the injected carrier density. The vanishing of excitonic lines together with the red-shift of the main emission evidences the occurrence of the Mott transition for a carrier concentration of (6 ± 3) × 1016 cm−3. This value is more than an order of magnitude smaller than previous determinations published in the literature and is in accordance with many-body calculations.
Two-phase binding of drug in a three-layered arterial wall following stent implantation
Authors: Mandal Akash Pradip , Mandal Prashanta Kumar
Published: February 2022

The present study explores the distribution and the binding of drug eluted from an embedded drug-eluting stent (DES), having struts of the circular cross-section. The arterial tissue is composed of three distinct layers, namely, the intima, the media and the adventitia, with varying diffusivity, and at the interfaces between different layers, a jump condition is imposed. The transport of free drug is modelled by the convection–diffusion-reaction process while the binding of drug is modelled by a nonlinear saturable reversible chemical reaction only. This model incorporates two types of binding mechanisms, namely, the specific binding caused by the interaction of drug and receptors, and the non-specific binding due to the gripping of drug in the extracellular medium (ECM). Furthermore, a constant as well as time-dependent release kinetics have been considered. All the governing equations along with suitable initial, boundary and jump interface conditions in cylindrical polar coordinate system are solved successfully by using the finite difference method. In this study, several clinical key factors like the degree of strut embedment, inter-strut distance (ISD), release mechanism are examined thoroughly. The study reveals that the inclusion of different layers along with jump interface conditions has a remarkable impact on stent-based delivery. Simulated results predict that a higher concentration profile for free drug and rapid saturation of binding sites take place for a half-embedded stent as compared to a quarterly and well-apposed stent. An intriguing feature is to be noted that the inter-strut distance through which the transmural plasma filtration takes place, plays a pivotal role in the distribution and retention of drug in the therapeutic domain considered. Furthermore, the steady-state simulation predicts the influence of strut dimension on the distributions of all drug forms.
Pressure-induced phase transition in transition metal trifluorides
Authors: Liu Peng , Xu Meiling , Lv Jian , Gao Pengyue , Huang Chengxi , Li Yinwei , Wang Jianyun , Wang Yanchao , Zhou Mi
Published: February 2022

As a fundamental thermodynamic variable, pressure can alter the bonding patterns and drive phase transitions leading to the creation of new high-pressure phases with exotic properties that are inaccessible at ambient pressure. Using the swarm intelligence structural prediction method, the phase transition of TiF3, from R–3c to the Pnma phase, was predicted at high pressure, accompanied by the destruction of TiF6 octahedra and formation of TiF8 square antiprismatic units. The Pnma phase of TiF3, formed using the laser-heated diamond-anvil-cell technique was confirmed via high-pressure x-ray diffraction experiments. Furthermore, the in situ electrical measurements indicate that the newly found Pnma phase has a semiconducting character, which is also consistent with the electronic band structure calculations. Finally, it was shown that this pressure-induced phase transition is a general phenomenon in ScF3, VF3, CrF3, and MnF3, offering valuable insights into the high-pressure phases of transition metal trifluorides.
Short-range correlation effects in neutron star's radial and non-radial oscillations *
Authors: Hong Bin , Ren ZhongZhou , Mu Xue-Ling
Published: February 2022

In this study, we determine the influence of the nucleon-nucleon short range correlation (SRC) on static spherically symmetric neutron stars (NSs) from the perspectives of radial and nonradial oscillations for the first time. We revise the equation of state and coupling parameters in the relativistic mean field theory after considering the SRC effect, and select the hyperon coupling parameters as the SU(3) model. For the non-radial oscillations, the SRC effect decreases the

-mode frequency by

kHz. For the radial oscillations, it decreases the fundamental radial frequency

by 0.75 ~ 0.85 kHz. Additionally, we refit the linear relationship between the average density and

-mode frequency for SRC. Combining the characteristics of the radial and non-radial frequencies, we provide a view of inferring the maximum mass of NSs. Owing to the characteristics of the SRC influence on the radial frequency, we expect that the SRC can be tested by future observation and can also be used as a probe for the structure inside NSs.
Design of the cross-polarization scattering diagnostic on the HL-2A tokamak
Authors: Tong R.H. , Zhong W.L. , Wen J. , Shi Z.B. , Zou X.L. , Liang A.S. , Yang Z.C. , Fang K.Y. , Jiang M. , Shi P.W. , Yu X. , Zhou Y. , Xu M.
Published: February 2022

A new cross-polarization scattering (CPS) diagnostic has been developed on HL-2A, which aims to measure the local magnetic fluctuation inside the plasma. It is based on the scattering of an incident microwave beam into the perpendicular polarization by magnetic fluctuations. The CPS diagnostic has been designed in the Q-band (33–50 GHz), which consists of the electronic system, quasi-optical, and polarization rejector. The ray-tracing code is used to simulate the propagation of the probe and scattered rays. To test the performance of the quasi-optical system, a 3D test platform is built and detailed test results are shown. Two methods are developed for polarization rejector on HL-2A: wire grid polarizer and dual-polarized horn antenna (DPHA). The laboratory test result shows that the polarization rejection of both methods is better than 30 dB, which meets the needs for magnetic fluctuation detection. In the future, the CPS diagnosis will be used to study the electromagnetic turbulence behavior in the high-performance plasma of the HL-2A tokamak.
Measuring the impacts of a real-world neighborhood-scale cool pavement deployment on albedo and temperatures in Los Angeles
Authors: Ko Joseph , Schlaerth Hannah , Bruce Alexandra , Sanders Kelly , Ban-Weiss George
Published: February 2022

Climate change is expected to exacerbate the urban heat island (UHI) effect in cities worldwide, increasing the risk of heat-related morbidity and mortality. Solar reflective ‘cool pavement’ is one of several mitigation strategies that may counteract the negative effects of the UHI effect. An increase in pavement albedo results in less heat absorption, which results in reduced surface temperatures (T
surface). Near surface air temperatures (T
air) could also be reduced if cool pavements are deployed at sufficiently large spatial scales, though this has never been confirmed by field measurements. This field study is the first to conduct controlled measurements of the impacts of neighborhood-scale cool pavement installations. We measured the impacts of cool pavement on albedo, T
surface, and T
air. In addition, pavement albedo was monitored after installation to assess its degradation over time. The field site (∼0.64 km2) was located in Covina, California; ∼30 km east of Downtown Los Angeles. We found that an average pavement albedo increase of 0.18 (from 0.08 to 0.26) corresponded to maximum neighborhood averaged T
surface and T
air reductions of 5 °C and 0.2 °C, respectively. Maximum T
surface reductions were observed in the afternoon, while minimum reductions of 0.9 °C were observed in the morning. T
air reductions were detected at 12:00 local standard time (LST), and from 20:00 LST to 22:59 LST, suggesting that cool pavement decreases T
air during the daytime as well as in the evening. An average albedo reduction of 30% corresponded to a ∼1 °C reduction in the T
surface cooling efficacy. Although we present here the first measured T
air reductions due to cool pavement, we emphasize that the tradeoffs between T
air reductions and reflected shortwave radiation increases are still unclear and warrant further investigation in order to holistically assess the efficacy of cool pavements, especially with regards to pedestrian thermal comfort.
Pattern capacity of a single quantum perceptron
Authors: Benatti Fabio , Gramegna Giovanni , Mancini Stefano
Published: February 2022

Recent developments in quantum machine learning have seen the introduction of several models to generalize the classical perceptron to the quantum regime. The capabilities of these quantum models need to be determined precisely in order to establish if a quantum advantage is achievable. Here we use a statistical physics approach to compute the pattern capacity of a particular model of quantum perceptron realized by means of a continuous variable quantum system.