bluuebunny/crossref_metadata_2025 huggingface dataset:
A phase II study of the safety of olanzapine for oxaliplatin based chemotherapy in coloraectal patients
Authors: Nishimura Junichi , Hasegawa Akiko , Kudo Toshihiro , Otsuka Tomoyuki , Yasui Masayoshi , Matsuda Chu , Haraguchi Naotsugu , Ushigome Hajime , Nakai Nozomu , Abe Tomoki , Hara Hisashi , Shinno Naoki , Asukai Kei , Hasegawa Shinichiro , Yamada Daisaku , Sugimura Keijiro , Yamamoto Kazuyoshi , Wada Hiroshi , Takahashi Hidenori , Omori Takeshi , Miyata Hiroshi , Ohue Masayuki
Published: February 2021

Olanzapine has exhibited efficacy as an antiemetic agent when used with 5-HT3 receptor antagonists, dexamethasone, and NK1 receptor antagonists for patients receiving highly emetogenic chemotherapy. In addition, several studies have reported the efficacy or safety of olanzapine in patients receiving moderately emetogenic chemotherapy, including carboplatin, irinotecan, and oxaliplatin. However, no reports of olanzapine use have focused on patients receiving oxaliplatin-based chemotherapy. Therefore, we analyzed the safety of antiemetic therapy using olanzapine, palonosetron, aprepitant, and dexamethasone in colorectal cancer patients undergoing oxaliplatin-based chemotherapy. This study was a prospective phase II single-institution study of 40 patients (median age 60 years, 23 patients were male). The primary endpoint was the incidence of adverse events, and the exploratory endpoints were the rate of chemotherapy-induced nausea and vomiting. Almost all patients (90%) had a performance status of 0. All patients received the scheduled antiemetic therapy. The most common adverse event was somnolence (n = 7 patients, 17.5%). All adverse events were grade 1. Thirty-six patients were included in the exploratory analysis of efficacy. No patients experienced vomiting during the first 120 h after chemotherapy, and complete response and complete control were both 86.1%. The rate of total control was 55.6% during the same time period. Olanzapine use with 5-HT3 receptor antagonists, dexamethasone, and NK1 receptor antagonists was safe for colorectal cancer patients receiving oxaliplatin-based chemotherapy.
Reduction of mortality by catheter ablation in real-world atrial fibrillation patients with heart failure
Authors: Yang Pil-Sung , Kim Daehoon , Sung Jung-Hoon , Jang Eunsun , Yu Hee Tae , Kim Tae-Hoon , Uhm Jae-Sun , Kim Jong-Youn , Pak Hui-Nam , Lee Moon-Hyoung , Joung Boyoung
Published: February 2021

Whether catheter ablation for atrial fibrillation (AF) improves survival and affects other outcomes in real-world heart failure (HF) patients is unclear. This study aimed to evaluate whether ablation reduces death, and other outcomes in real-world AF patients with HF. Among 834,735 patients with AF from 2006 to 2015 in the Korean National Health Insurance Service database, 3173 HF patients underwent AF ablation. Propensity score weighting was used to correct for differences between the groups. During median 54 months follow-up, the risk of all-cause death in ablated patients was less than half of that in patients with medical therapy (2.8 vs. 6.2 per 100 person-years; hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.27–0.65, p < 0.001). Ablation was related with lower risk of cardiovascular death (HR 0.38, 95% CI 0.32–0.62, p < 0.001), HF admission (HR 0.39, 95% CI 0.33–0.46, p < 0.001) and stroke/systemic embolism (HR 0.44, 95% CI 0.37–0.53, p < 0.001). In subgroup analysis, the risk of all-cause death was reduced in most subgroups except in the elderly (≥ 75 years) and strictly anticoagulated patients. Ablation may be associated with reduced risk of all-cause death and cardiovascular death in real-world AF patients with HF, supporting the role of AF ablation in patients with HF.
Changing gloves during cesarean section for prevention of postoperative infections: a systematic review and meta-analysis
Authors: Rattanakanokchai Siwanon , Eamudomkarn Nuntasiri , Jampathong Nampet , Luong-Thanh Bao-Yen , Kietpeerakool Chumnan
Published: February 2021

This systematic review and meta-analysis was conducted to assess associations between changing gloves during cesarean section (CS) and postoperative infection. A literature search was conducted using the major electronic databases MEDLINE, Scopus, ISI Web of Science, PubMed, CINAHL, and CENTRAL from their inception to September 2020. Randomized controlled trials (RCTs) comparing glove change during CS to no glove change were included. Outcomes of interest were endometritis, febrile morbidity, and incisional surgical site infection (SSI). GRADE approach was applied to assess the quality of evidence. Ten reports of six studies involving 1707 participants were included in the analyses. Glove change was associated with a reduction in the risk of incisional SSI following CS (pooled RR 0.49, 95% CI 0.30, 0.78; moderate quality of evidence). Compared to no glove change, glove change during CS did not reduce the risks of endometritis (pooled RR 1.00, 95% CI 0.80, 1.24; low quality of evidence) or febrile morbidity (pooled RR 0.85, 95% CI 0.43, 1.71; very low quality of evidence). Changing gloves during CS was associated with a decreased risk of incisional SSI. The risks of postoperative endometritis and febrile morbidity were not altered by changing gloves.
Wiskott Aldrich syndrome: healthcare utilizations and disparities in transplant care
Authors: Agarwal Nikki , Citla Sridhar Divyaswathi , Malay Sindhoosha , Patil Nirav , Shekar Anjali , Ahuja Sanjay , Dalal Jignesh
Published: February 2021

Wiskott Aldrich syndrome (WAS) is a rare disease and hematopoietic stem cell transplant (HCT) is considered the treatment modality of choice for WAS. We conducted a cross-sectional analysis on the KIDS’ pediatric inpatient database and compared hospitalization rates, complications and healthcare utilizations in the transplant and non-transplant arms. Of the 383 pediatric admissions with diagnosis of WAS between 2006–2012, 114 underwent transplant and 269 did not. The non-transplant arm included older children, female patients and more African Americans. Death rates, income and payer source were similar in both arms, however the total charge for each admission was higher in the transplant arm. Emergency room visits were similar but non-elective admissions were more in the non-transplant arm. Length of stay was prolonged in the transplant arm. When comparing morbidities, lymphomas, ulcerative colitis and autoimmune complications of WAS were seen only in the non-transplant arm. Our study shows that transplant is the largest contributor to healthcare utilization in WAS patients. We identified healthcare disparities based on race and socioeconomic status and found that this rare disease is being appropriately directed to centers with HCT expertise. We noted a change in practice moving away from splenectomy in WAS patients.
Author Correction: Genome editing in plants using CRISPR type I-D nuclease
Authors: Osakabe Keishi , Wada Naoki , Miyaji Tomoko , Murakami Emi , Marui Kazuya , Ueta Risa , Hashimoto Ryosuke , Abe-Hara Chihiro , Kong Bihe , Yano Kentaro , Osakabe Yuriko
Published: February 2021

A Correction to this paper has been published: https://doi.org/10.1038/s42003-021-01771-5
In situ characterisation of phytohormones from wounded Arabidopsis leaves using desorption electrospray ionisation mass spectrometry imaging
Authors: Zhang Chao , Žukauskaitė Asta , Petřík Ivan , Pěnčík Aleš , Hönig Martin , Grúz Jiří , Široká Jitka , Novák Ondřej , Doležal Karel
Published: February 2021

The distribution of target phytohormones is highlighted in wounded Arabidopsis leaves, the differences in their abundance are determined, and the correlations between them are analysed using DESI-MSI analysis.
A Pt–Ir nanocube amplified lateral flow immunoassay for dehydroepiandrosterone
Authors: Yang Huiyi , He Qiyi , Pan Junkang , Shen Ding , Xiao Huanxin , Cui Xiping , Zhao Suqing
Published: February 2021

A Pt–Ir nanocube amplified lateral flow immunoassay for dehydroepiandrosterone determination was demonstrated.
Boosting Li3V2(PO4)3 cathode stability using a concentrated aqueous electrolyte for high-voltage zinc batteries
Authors: Li Cuixia , Yuan Wentao , Li Chi , Wang Huan , Wang Liubin , Liu Yongchang , Zhang Ning
Published: February 2021

An aqueous Zn//Li3V2(PO4)3 battery in a concentrated hybrid electrolyte exhibits a high out-put voltage of 1.75 V, a stable capacity of 126.7 mA h g−1, and a long cycling life.
High-temperature superconductivity in transition metallic hydrides MH11(M = Mo, W, Nb, and Ta) under high pressure
Authors: Du Mingyang , Zhang Zihan , Song Hao , Yu Hongyu , Cui Tian , Kresin Vladimir Z. , Duan Defang
Published: February 2021

The contribution of optical and acoustic modes to the superconducting transition temperature. The calculated EPC parameterλ, critical temperature (Tc), critical temperature caused by the interaction of electrons with optical phonons (T0c) and acoustic phonons (Tacc).
Origins of low lattice thermal conductivity of Pb1−xSnxTe alloys for thermoelectric applications
Authors: Knura Rafal , Parashchuk Taras , Yoshiasa Akira , Wojciechowski Krzysztof T.
Published: February 2021

The lattice thermal conductivity of Pb1−xSnxTe solid solutions was determined directly from the lattice dynamics data obtained by XAFS spectroscopy.
Modification of cellulose through physisorption of cationic bio-based nanolatexes – comparing emulsion polymerization and RAFT-mediated polymerization-induced self-assembly
Authors: Alexakis Alexandros E. , Engström Joakim , Stamm Arne , Riazanova Anastasia V. , Brett Calvin J. , Roth Stephan V. , Syrén Per-Olof , Fogelström Linda , Reid Michael S. , Malmström Eva
Published: February 2021

Investigation of film formation of cationically charged nanolatexes comprised of terpene-derived monomer synthesized with emulsion and RAFT-mediated polymerization induce self-assembly on cellulose.
Crosstalk effects of the surface layers of metallic samples on laser-induced breakdown spectroscopy measurements
Authors: Meinhardt Christoph , Noll Reinhard , Fricke-Begemann Cord
Published: February 2021

Material ablation driven by focused laser pulses is an important aspect of laser-induced breakdown spectroscopy (LIBS). Schematics of the studied measuring object as model artefact for non-representative surface layers.
Review of microfluidic approaches for fabricating intelligent fiber devices: importance of shape characteristics
Authors: Wu Ronghui , Kim Taesung
Published: February 2021

Intelligent fiber devices with shape characteristics tailored by microfluidic approaches are reviewed, including sensors and actuators, luminous fibers, and devices for water collection, energy harvesting, and tissue engineering applications.
Effects of rare earth metal doping on Au/ReZrO2 catalysts for efficient hydrogen generation from formic acid
Authors: Wu Luming , Hao Yu , Chen Shaohua , Chen Rui , Sun Pingchuan , Chen Tiehong
Published: February 2021

Rare earth metal doped ZrO2 can promote the formation of oxygen vacancies in zirconia, which enhances the metal–support interaction, finally promoting catalytic activity of FA dehydrogenation.
Chemical labeling strategies for small molecule natural product detection and isolation
Authors: Hughes Chambers C.
Published: February 2021

Chemical labeling enhances the analysis of complex mixtures via HPLC-MS in both targeted and untargeted metabolomics workflows.
3D porous Ni/NiOx as a bifunctional oxygen electrocatalyst derived from freeze-dried Ni(OH)2
Authors: Shudo Yuta , Fukuda Masahiro , Islam Md. Saidul , Kuroiwa Keita , Sekine Yoshihiro , Karim Mohammad Razaul , Hayami Shinya
Published: February 2021

3D porous Ni/NiOx was synthesized via the freeze-drying method. Freeze drying method could improve the surface area and catalytic activation of Nickel hydroxide nanosheet.
Phonon transport in the nano-system of Si and SiGe films with Ge nanodots and approach to ultralow thermal conductivity
Authors: Taniguchi Tatsuhiko , Terada Tsukasa , Komatsubara Yuki , Ishibe Takafumi , Konoike Kento , Sanada Atsushi , Naruse Nobuyasu , Mera Yutaka , Nakamura Yoshiaki
Published: February 2021

Ballistic phonon transport was observed in Si films containing Ge nanodots. In SiGe films containing Ge nanodots, thermal conductivity was drastically reduced close to that of amorphous materials due to alloy phonon scattering and nanodot scattering.
An all-female graduate student organization participating in chemistry outreach: a case study characterizing leadership in the community of practice
Authors: Santos-Díaz Stephanie , Towns Marcy H.
Published: February 2021

Outreach initiatives are typically framed as informal learning environments that provide an opportunity to increase the participants’ interest in science. Research on chemistry outreach has primarily focused on designing and implementing demonstrations for outreach. Recent studies indicate student organizations are at the forefront of chemistry outreach, describing their outreach practices and facilitators’ conceptual understanding of demonstrations. Although leadership has been linked to the success of groups and organizations, the leadership structure of student organizations is an understudied aspect of chemistry outreach. Here, we conceptualize student organizations participating in chemistry outreach as a community of practice (CoP) with the goal of expanding the chemistry education community's knowledge of this CoP. Specifically, we aim to characterize leadership styles within the student organization in the context of an outreach event. Using a case study approach, we collected multiple sources of data, including the organization's outreach practices, an assessment of leadership style, observations, and semi-structured interviews. Results indicate leaders of the student organization, particularly those in charge of planning outreach events, displayed behaviors associated with the transactional and laissez-faire leadership styles more frequently than behaviors associated with the transformational leadership style. As a long-term outcome for this study, the results can be used by national organizations to inform the development of new workshops for leadership training, with the purpose of teaching practices to leaders that can bring success to their chapter or local group.
An anthracene extended viologen-incorporated ionic porous organic polymer for efficient aerobic photocatalysis and antibacterial activity
Authors: Liu Lu , Qu Wei-Dong , Dong Kai-Xun , Qi Ye , Gong Wei-Tao , Ning Gui-Ling , Cui Jing-Nan
Published: February 2021

Herein, a new conjugated porous organic polymer, AN-POP, with anthracene-containing π-extended viologens has been designed and prepared to explore its dual functions in photo-catalytic oxidation and bacterial killing.
Thioguanine restoration through type I photosensitization-superoxide oxidation-glutathione reduction cycles
Authors: Euceda Nelson , Jahnke Joyce , Espinal Aileen , Louis Monique F. , Bashkin Edan , Roccanova Patricia , Espaillat Abraham , Fuentes German V. , Nieto Fernando , Gao Ruomei
Published: February 2021

The production of superoxide radicals is enhanced 10-fold upon UVA irradiation of 6-thioguanine in the presence of reduced glutathione.
Quadruple-layer group-IV tellurides: low thermal conductivity and high performance two-dimensional thermoelectric materials
Authors: Wei Qiang-Lin , Zhu Xue-Liang , Liu Peng-Fei , Wu Yi-Yuan , Ma Jiang-Jiang , Liu Yi-Bao , Li Yu-Hong , Wang Bao-Tian
Published: February 2021

Two-dimensional hexagonal group-IV tellurides XTe (X = Ge, Sn, Pb) with a narrow band gap exhibit high-performance medium-temperature thermoelectric characteristics.
Robust covalent organic frameworks with tailor-made chelating sites for synergistic capture of U(vi) ions from highly acidic radioactive waste
Authors: Yu Jipan , Lan Jianhui , Wang Shuai , Zhang Pengcheng , Liu Kang , Yuan Liyong , Chai Zhifang , Shi Weiqun
Published: February 2021

A synergistic strategy for enhancing U(vi) capture under highly acidic condition (2 M HNO3) by radiation resistant phosphonate-grafted two-dimensional covalent organic frameworks with tailor-made binding sites bearing a strong affinity was described.
Positive zero-field splitting and unexpected slow magnetic relaxation in the magneto-chemical calibrant HgCo(NCS)4
Authors: Boča Roman , Titiš Ján , Rajnák Cyril , Krzystek J.
Published: February 2021

Magnetochemical standard HgCo(NCS)4 with positive zero-field splitting parameter D displays a slow magnetic relaxation strongly dependent upon the external magnetic field.
Aromatic Cope rearrangements
Authors: Tomiczek Breanna M. , Grenning Alexander J.
Published: February 2021

This review summarizes the ∼40 papers dating back to 1956 on the aromatic Cope rearrangement, and highlights the need for further studies, development, and applications of this transformation in synthesis.
Retraction: Convenient synthesis of pyrimidine 2′-deoxyribonucleoside monophosphates with important epigenetic marks at the 5-position
Authors: Zheng Song , Tran Ai , Curry Alyson M. , White Dawanna S. , Cen Yana
Published: February 2021

Retraction of ‘Convenient synthesis of pyrimidine 2′-deoxyribonucleoside monophosphates with important epigenetic marks at the 5-position’ by Song Zheng et al., Org. Biomol. Chem., 2020, 18, 5164–5173, DOI: 10.1039/D0OB00884B.
β-Methyl-δ-valerolactone-containing thermoplastic poly(ester-amide)s: synthesis, mechanical properties, and degradation behavior
Authors: Guptill David M. , Chinta Bhavani Shankar , Kaicharla Trinadh , Xu Shu , Hoye Thomas R.
Published: February 2021

These hydrolytically degradable poly(ester-amide)s show improved solubility and enhanced thermal and mechanical properties.
Retraction: Functional disruption of staphylococcal accessory regulator A from Staphylococcus aureus by silver ions
Authors: Liao Xiangwen , Jiang Guijuan , Wang Jing , Wang Jintao
Published: February 2021

Retraction of ‘Functional disruption of staphylococcal accessory regulator A from Staphylococcus aureus by silver ions’ by Xiangwen Liao et al., RSC Adv., 2020, 10, 33221–33226. DOI: 10.1039/D0RA06357F.
Retraction: Divergent synthesis of 5-substituted pyrimidine 2′-deoxynucleosides and their incorporation into oligodeoxynucleotides for the survey of uracil DNA glycosylases
Authors: Tran Ai , Zheng Song , White Dawanna S. , Curry Alyson M. , Cen Yana
Published: February 2021

Retraction of ‘Divergent synthesis of 5-substituted pyrimidine 2′-deoxynucleosides and their incorporation into oligodeoxynucleotides for the survey of uracil DNA glycosylases’ by Ai Tran et al., Chem. Sci., 2020, 11, 11818–11826, DOI: 10.1039/D0SC04161K.
Super‐pixel image segmentation algorithm based on adaptive equalisation feature parameters
Authors: Ding Shifei , Wang Lijuan , Cong Lin
Published: February 2021

Image segmentation is a key step in the process of image data processing. The quality of image segmentation will directly affect the accuracy of image cognitive understanding. The purpose of image segmentation is to divide the image into regions with specific semantics. For the simple linear iterative clustering (SLIC) algorithm, the feature equalisation parameters need to be set manually during image segmentation, which results in the lack of segmentation effects and slow processing time. By introducing the theory of intermediary mathematics, an improved adaptive SLIC super‐pixel algorithm is proposed, which can adaptive generate characteristic equalisation parameters according to the specific situation of the image, thereby simplifying the operation steps and improving the image segmentation effect. After experimental verification and analysis, compared with the original SLIC algorithm and several other super‐pixel contrast algorithms, the algorithm in this study can effectively shorten the processing time and achieve a better segmentation effect.
Real‐time keypoints detection for autonomous recovery of the unmanned ground vehicle
Authors: Li Jie , Zhang Sheng , Han Kai , Yuan Xia , Zhao Chunxia , Liu Yu
Published: February 2021

The combination of a small unmanned ground vehicle (UGV) and a large unmanned carrier vehicle allows more flexibility in real applications such as rescue in dangerous scenarios. The autonomous recovery system, which is used to guide the small UGV back to the carrier vehicle, is an essential component to achieve a seamless combination of the two vehicles. This study proposes a novel autonomous recovery framework with a low‐cost monocular vision system to provide accurate positioning and attitude estimation of the UGV during navigation. First, the authors introduce a light‐weight convolutional neural network called UGV‐KPNet to detect the keypoints of the small UGV form the images captured by a monocular camera. UGV‐KPNet is computationally efficient with a small number of parameters and provides pixel‐level accurate keypoints detection results in real‐time. Then, six degrees of freedom (6‐DoF) pose is estimated using the detected keypoints to obtain positioning and attitude information of the UGV. Besides, they are the first to create a large‐scale real‐world keypoints data set of the UGV. The experimental results demonstrate that the proposed system achieves state‐of‐the‐art performance in terms of both accuracy and speed on UGV keypoint detection, and can further boost the 6‐DoF pose estimation for the UGV.
Synthetic medical image generator for data augmentation and anonymisation based on generative adversarial network for glioblastoma tumors growth prediction
Authors: Kamli Adel , Saouli Rachida , Batatia Hadj , Naceur Mostefa Ben , Youkana Imane
Published: February 2021

Prediction methods of glioblastoma tumours growth constitute a hard task due to the lack of medical data, which is mostly related to the patients' privacy, the cost of collecting a large medical data set, and the availability of related notations by experts. In this study, the authors propose a synthetic medical image generator (SMIG) with the purpose of generating synthetic data based on the generative adversarial network in order to provide anonymised data. In addition, to predict the glioblastoma multiform tumour growth the authors developed a tumour growth predictor based on end to end convolution neural network architecture that allows training on a public data set from the cancer imaging archive (TCIA), combined with the generated synthetic data. The authors also highlighted the impact of implicating a synthetic data generated using SMIG as a data augmentation tool. Despite small data size provided by TCIA data set, the obtained results demonstrate valuable tumour growth prediction accuracy.
Analysis of a DC–DC quadratic type step‐down converter for wider low voltage conversion
Authors: Misal Shrikant , Veerachary Mummadi
Published: February 2021

This study proposes a new transformerless DC–DC step‐down converter having the quadratic type of wider voltage gain, for point‐of‐load applications. In comparison to existent quadratic buck converter variants, the proposed topology offers better switch utilisation at small output voltages and reduced voltage/current stress on components. The stress minimisation benefit helps to select low ON‐state resistance switch in the proposed converter, thereby decreasing its conduction losses. Qualitative steady‐state analysis is carried out under continuous inductor current mode and design criteria for L‐C components are established. State‐space average model is derived and subsequently, an equivalent sliding mode control law based on just source side inductor current dynamics and integral of load voltage error is constituted to regulate the output. Salient operational characteristics of the converter are studied analytically and illustrated thereafter using experimental outcomes on a laboratory prototype.
Economic operation of integrated energy systems considering combined production of hydrogen and medical oxygen
Authors: Ding Haohui , Hu Qinran , Ge Yi , Wu Qiuwei , Dou Xiaobo , Li Yang
Published: February 2021

Developing integrated energy systems have been considered a feasible pathway to renewable‐powered energy systems. The power to hydrogen technology is recognised as a promising method to enhance the economics of integrated energy systems and help reduce renewable curtailments. However, oxygen‐enriched gas, which is the by‐product of power to hydrogen processes (electrolysation), has not been fully utilised yet. It can be purified to produce medical oxygen at a low cost and may further increase the economics of integrated energy systems. Particularly, at this very moment, the consideration of the combined production of hydrogen and medical oxygen also has the potential to relieve the shortage of medical oxygen due to the outbreak of the 2019 novel coronavirus (COVID‐19). This study proposes a model for the operation of integrated energy systems that consider the combined production of hydrogen and medical oxygen. This model is formulated as a convex mixed‐integer optimisation problem that balances the electricity, heat and hydrogen demands every hour in a 24‐hour period and balances oxygen demand on a daily basis. A test case of Taizhou City has been studied and results show that the combined production of hydrogen and medical oxygen improves the integrated energy system economics.
Dual‐band‐independent tunable multiple‐input–multiple‐output antenna for 4G/5G new radio access network applications
Authors: Hussain Rifaqat
Published: February 2021

Slot‐based dual‐band, low‐profile frequency reconfigurable (FR) multiple‐input–multiple‐output (MIMO) antenna design is presented here. Each element is composed of concentric annular slots that are loaded reactively using varactor diodes. Accurate placement of diodes and optimal biasing circuit configuration result in complete control on each of the tuned bands. The unique feature of the proposed work is the independent as well as concurrent tuning of each band over a wide frequency range from 1.7 to 3.8 GHz. Moreover, the competitive advantage of independent tuning and its narrow‐band (NB) operation may result in better power management for RF front‐end devices. The proposed antenna is fabricated using an RO‐4350 substrate with board dimensions 60 × 120 × 0.76 mm3. The proposed dual‐band compact antenna design is suitable to be utilized in the current fourth generation (4G) wireless standards as well as for upcoming fifth generation (5G) new radio access networks (RANs) with sub 6‐GHz operation.
A single‐layer high‐gain dipole antenna array with a bidirectional radiation pattern based on parallel‐strip line
Authors: Wu Zhe , Yun Yu , Miao Zhuang , Lennerstad Håkan
Published: February 2021

A single‐layer dipole antenna array with quasi‐Yagi configuration has been proposed and demonstrated, which provides a dual radiation pattern with the same sense. This antenna is mainly composed of a substrate‐supported parallel strip line (PSL) and several periodic dipole elements. Fed by PSL, dipole elements can be stimulated with a uniform power, forming a linear dipole antenna array. By adjusting the elements separation appropriately, the step phase of array factor can be tuned to achieve the same directivity as the element dipole. When an SubMiniature version A (SMA) coaxial connector is connected at the beginning of PSL, the fundamental mode TEM in the PSL is excited and the radiation electromagnetic wave from the dipole elements is achieved. A taper line between the SMA and PSL can be used to reduce the discontinuity, minimizing the reflection coefficient of the port. According to the theory of classical Yagi antenna, the gain can be further improved by introducing multiple directors, achieving the gain increment of about 3 dBi in the proposed design. Considering 5 GHz frequency band applications (4.85–5.2 GHz), the experimental and simulated results show the proposed antenna array has a working bandwidth from 4.85 to 12 GHz.
Starspot modelling of the TESS light curve of CVSO 30
Authors: Koen C.
Published: February 2021

Aims. I aim to investigate whether the photometric variability in the candidate host star CVSO 30 can be explained by starspots.

Methods. The Transiting Exoplanet Survey Satellite (TESS) light curve of CVSO 30 is separated into two independent non-sinusoidal periodic components. A starspot modelling technique is applied to each of these components.

Results. Combined, the two model light curves reproduce the TESS observations to a high accuracy, obviating the need to invoke planetary transits to describe part of the variability.
Physical properties and structure characteristics of titanium-modified antimony-selenium phase change thin film
Authors: Wu Weihua , Sun Yuemei , Zhu Xiaoqin , Shen Bo , Zhai Jiwei , Yue Zhenxing
Published: February 2021

Effects of the titanium dopant on the physical properties and structure of SbSe thin films were systematically investigated by experiments and first-principles calculations. The amorphous-to-polycrystalline transformation induced by heat was examined by in situ electrical resistance measurements. With the incorporation of titanium atoms, both the crystallization temperature and electrical resistance increase, revealing the improvement of the amorphous thermal stability and programing energy consumption. X-ray diffraction, transmission electron microscopy, and density functional theory calculations illustrate that a small amount of titanium dopant can inhibit the grain growth and refine the crystal size. The shift of Raman modes associated Sb upon the crystallization was observed. X-ray reflectivity and atomic force microscopy results prove the smaller volume fluctuation and the smoother surface morphology, meaning the better interfacial property and reliability of titanium-doped SbSe materials. Phase change memory cells based on titanium-doped antimony-selenium were fabricated to evaluate the electrical performance as well. All these results indicate that the suitable incorporation of the titanium element will be an effective method to optimize the physical properties and tune the structure of the SbSe phase change material.
Anisotropic ɛ-near-zero multilayer structures for omnidirectional bending to the normal
Authors: Freeman Will
Published: February 2021

Anisotropic ɛ-near-zero effective medium multilayer structures for omnidirectional bending light to the normal are theoretically studied. A finite element method is presented, using a unit cell with Floquet port master and slave boundaries, for examining metal–dielectric multilayer structures to form the permittivity tensor. Ellipsometry measurements of CdO films are reported, and it is found that film thicknesses of ∼50 nm are adequate for the metallic layer. Omnidirectional bending to the normal is verified for multilayer structures, and this method is shown to simplify the computations over using a typical full space approach.
Light reflectance and photoelectron yield spectroscopy enable acceptor level measurement in p-type Ba1−xTiO3 semiconductor
Authors: Fujii Saya , Kano Jun , Oshime Norihiro , Higuchi Tohru , Nishina Yuta , Fujii Tatsuo , Ikeda Naoshi , Ota Hiromi
Published: February 2021

We report the band structure of Ba-deficient BaTiO3 as a p-type semiconductor, studied by a combination of light reflectance and photoelectron yield spectroscopy. Two acceptor levels were observed at the tail of a valence band. As the quantity of Ba vacancies increased, the density of state of the two acceptor levels also increased. The levels of the conduction band minimum and the valence band maximum shifted far away from the vacuum level, but the bandgap seems to be independent of Ba deficient concentration. For classical semiconductors such as Si and GaAs, the observation of impurity levels is restricted to low temperatures (∼20 K) owing to their narrow bandgaps. Oxide semiconductors have now been demonstrated with wide bandgaps and acceptor levels, at normal operating temperatures, which could lead to new device designs in the future.
Room-temperature deposition of a poling-free ferroelectric AlScN film by reactive sputtering
Authors: Tsai Sung-Lin , Hoshii Takuya , Wakabayashi Hitoshi , Tsutsui Kazuo , Chung Tien-Kan , Chang Edward Y. , Kakushima Kuniyuki
Published: February 2021

Crystallographic characterization and the ferroelectric properties of 50 nm-thick sputter-deposited Al0.78Sc0.22N films deposited at room temperature (RT) and 400 °C are investigated. c-axis oriented growths were confirmed by x-ray diffraction patterns with rocking curve measurements for both samples. Al0.78Sc0.22N films were found to grow in the c-axis direction and showed poling-free ferroelectric properties, which are advantageous for practical memory and piezoelectric applications. Although the metal-ferroelectric-metal (MFM) capacitors represent low switching cycle endurance, MFM capacitors revealed remnant polarization (Pr) of 70 μC/cm2 and 113 μC/cm2 for RT- and 400 °C-deposited samples, respectively. Ferroelectric films with low-temperature process capability can open a wide range of applications.
Low noise Al0.85Ga0.15As0.56Sb0.44 avalanche photodiodes on InP substrates
Authors: Lee S. , Kodati S. H. , Guo B. , Jones A. H. , Schwartz M. , Winslow M. , Grein C. H. , Ronningen T. J. , Campbell J. C. , Krishna S.
Published: February 2021

We report on the demonstration of Al0.85Ga0.15As0.56Sb0.44 (hereafter, AlGaAsSb) avalanche photodiodes (APDs) with a 1000 nm-thick multiplication layer. Such a thick AlGaAsSb device was grown by a digital alloy technique to avoid phase separation. The current-voltage measurements under dark and illumination conditions were performed to determine gain for the AlGaAsSb APDs. The highest gain was ∼ 42, and the avalanche initiation occurred at 21.6 V. The breakdown voltage was found to be around −53 V. The measured dark current densities of bulk and surface components were 6.0 μA/cm2 and 0.23 μA/cm, respectively. These values are about two orders of magnitude lower than those for previously reported 1550 nm-thick AlAs0.56Sb0.44 APDs [Yi et al., Nat. Photonics 13, 683 (2019)]. Excess noise measurements showed that the AlGaAsSb APD has a low k of 0.01 (the ratio of electron and hole impact ionization coefficients) compared to Si APDs. The k of the 1000-nm AlGaAsSb APD is similar to that of the thick AlAsSb APDs (k ∼ 0.005) and 5–8 times lower than that of 170 nm-thick AlGaAsSb APDs (k ∼ 0.5–0.8). Increasing the thickness of the multiplication layer over 1000 nm can also reduce k further since the difference between electron and hole impact ionization coefficients becomes significant in this material system as the thickness of the multiplication layer increases. Therefore, this thick AlGaAsSb-based APD on an InP substrate shows the potential to be a high-performance multiplier that can be used with available short-wavelength infrared (SWIR) absorption layers for a SWIR APD.
Decay of stationary capillary waves on impinging liquid jets
Authors: Patrascu Claudiu , Balan Corneliu
Published: February 2021

This study is concerned with the capillary-wave field generated at the base of a liquid jet impinging on a liquid reservoir. Capillary waves on laminar liquid jets are investigated in terms of the spatial damping coefficient. We find an exponential decrease of the wave crests, with the decay rate given by theory. We show that a small increase in viscosity leads to rapid suppression of the wave-like behavior. This study also emphasizes the effect of viscoelasticity, which decreases the damping coefficient. A simple dependence on the combined Weber–Deborah number is proposed for the dimensionless damping coefficient. At the impact zone, similarities are found for the decay of the free surface compared to the classic model of a meniscus climbing on a cylindrical fiber, the radial jet profile taking the shape of a catenary curve. Theoretical predictions are found to be in good qualitative agreement with the experimental data.
Tip-induced flexoelectricity, polar vortices, and magnetic moments in ferroelastic materials
Authors: Lu Guangming , Li Suzhi , Ding Xiangdong , Sun Jun , Salje Ekhard K. H.
Published: February 2021

Flexoelectricity in twinned ferroelastic thin films generates polarity inside twin walls. The electrical dipoles are typically aligned parallel to twin walls while out-of-plane dipoles are induced elastically by an atomic force microscopy (AFM) tip or by atomic steps in the substrate. Molecular dynamics modeling shows that the out-of-plane dipoles form polar vortex structures next to the domain walls. Flexoelectricity, e.g., by moving AFM tips, produces displacement currents inside these vortices. We estimate that these displacement currents generate magnetic fields with moments in the order of 10−9 μB per atomic layer.
Tunable pipe-type acoustic metamaterials based on piezoelectric composite side-branches
Authors: Han Dong-Yu , Peng Yao-Yin , Liu Guang-Sheng , Zou Xin-Ye , Cheng Jian-Chun
Published: February 2021

The ability to tune the performance of acoustic metamaterials without structural modifications or complex active control circuits is a remarkable challenge. In this work, we present a square piezoelectric side-branch (PSB) pipe-type structure that consists of the piezoelectric composite sheets (PCSs) on its sidewall and propose the corresponding equivalent electroacoustic circuit model. Compared with the traditional side-branch, theoretical and numerical results show that the thickness of the PSB can be up to λ/200, and the tunable phase shift of the transmitted wave in the PSB pipe can achieve nearly 2π by adjusting the capacitances that are connected to the PCSs. The experiment for a square pipe with one PCS is also given to prove the phase control ability of the PSB model. Furthermore, we show that by merely adjusting the external capacitances of the PCSs, switching the functions between the 45° extraordinary transmission and the acoustic focusing for the same incident wave can be exactly realized. Our work provides a promising potential in active controls and integration designs of acoustic metamaterials and devices.
“Meta-atomless” architecture based on an irregular continuous fabric of coupling-tuned identical nanopillars enables highly efficient and achromatic metasurfaces
Authors: Yağcı H. Bilge , Demir Hilmi Volkan
Published: February 2021

Metasurfaces are subwavelength-thick constructs, consisting of discrete meta-atoms, providing discretized levels of phase accumulation that collectively approximate a designed optical functionality. The meta-atoms utilizing the Pancharatnam–Berry phase with polarization-converting structures produced encouraging implementations of optical components including metalenses. However, to date, a pending and fundamental problem of this approach has been the low device efficiency that such resulting metasurface components suffer, an unwanted side effect of large lattice constants that are used for preventing intercoupling of their meta-atoms. Although the use of near-field coupling for tuning electromagnetic resonances found its use in constructing efficient narrow-band designs, such structures fell short of providing high efficiency over a broad spectrum. Here, we propose and show that tightly packed fabrics of identical dielectric nanopillar waveguides with continuously tuned intercoupling distances make excellent and complete achromatic metasurface elements. This architecture enables the scatterers to interact with the incoming wave extremely efficiently. As a proof-of-concept demonstration, we showed an achromatic cylindrical metalens, constructed from strongly coupled dielectric nanopillars of a single geometry as continuously set phase elements in a meta-atomless fashion, working in the entirety of the 400–700 nm band. This metalens achieves over 85% focusing efficiency across this whole spectral range. To combat polarization sensitivity, we used hexagonally stacked nanopillars to build up a polarization-independent scatterer library. Finally, a circular metalens with polarization-independent operation and achromatic focusing was obtained. This is a paradigm shift in making an achromatic metasurface architecture by weaving identical nanopillars coupled into an irregular lattice laterally constructed via carefully tuned near-field coupling.
Calculation of new enteric methane emission factors for small ruminants in western Kenya highlights the heterogeneity of smallholder production systems
Authors: Goopy J. P. , Ndung'u P. W. , Onyango A. , Kirui P. , Butterbach-Bahl K.
Published: February 2021

Context
African livestock play a critical role in food security and the wider economy, while accounting for >70% of African agricultural greenhouse gas emissions. Accurate estimates of greenhouse gas emissions from livestock are required for inventory purposes and to assess the efficacy of mitigation measures. While there is an increasing number of studies assessing methane (CH4) emissions of cattle, little attention has been paid to small ruminants (SR).

Aims
Enteric CH4 emissions were assessed from 1345 SR in three counties of western Kenya to develop more accurate emission factors (EF) for enteric CH4 from sheep and goats.

Methods
Using on-farm animal activity data, feed samples were also analysed to produce estimates of feed digestibility by season and region. The combined data were also used to estimate daily CH4 production by season, location and class of animal to produce new EF for annual enteric CH4 production of SR.

Key results
Mean dry-matter digestibility of the feed basket was in the range of 58–64%, depending on region and season (~10% greater than Tier I estimates). EF were similar for sheep (4.4 vs 5 kg CH4/year), but lower for goats (3.7 vs 5 kg CH4/year) than those given for SR in developing countries in Intergovernmental Panel on Climate Change (Tier I) estimates.

Conclusions
Published estimates of EF for SR range widely across Africa. In smallholder systems in western Kenya, SR appear to be managed differently from cattle, and EF appear to be driven by different management considerations.

Implications
The findings highlighted the heterogenous nature of SR enteric emissions in East Africa, but also suggested that emissions from SR are quantitatively less important than other estimates suggest compared with cattle.
Vaccinating the oldest against COVID-19 saves both the most lives and most years of life
Authors: Goldstein Joshua R. , Cassidy Thomas , Wachter Kenneth W.
Published: February 2021

Many competing criteria are under consideration for prioritizing COVID-19 vaccination. Two criteria based on age are demographic: lives saved and years of future life saved. Vaccinating the very old against COVID-19 saves the most lives, but, since older age is accompanied by falling life expectancy, it is widely supposed that these two goals are in conflict. We show this to be mistaken. The age patterns of COVID-19 mortality are such that vaccinating the oldest first saves the most lives and, surprisingly, also maximizes years of remaining life expectancy. We demonstrate this relationship empirically in the United States, Germany, and South Korea and with mathematical analysis of life tables. Our age-risk results, under usual conditions, also apply to health risks.
La traduzione del podcast
Authors: Saina Francesco
Published: February 2021

Podcasting is increasingly widespread as a digital medium. However, it has not received sufficient or adequate attention yet, particularly regarding research and translation methodology. This article introduces a translation proposal for Serial, one of the most popular podcasts in the world. The case study aims to raise a debate among scholars and communication experts in order to create common strategies and models for translating podcasts, in the hope that it would pave the way for innovative and valuable communication channels, application in pedagogy, and job opportunities in an unexplored scenario.
A cross-boundary approach to the generative nature of translation
Authors: Tan Zaixi
Published: February 2021

Applying insights from Shi Er’s philosophic-cultural studies-based “boundary theory” to the construal of the nature of
translation, this paper discusses the various aspects of what could be regarded as a generative approach to defining translation, ranging
from the idea that translation is a “cross-boundary” activity of communication to the concept of translational generativity and to analyzing
the fundamental properties of what could qualify or disqualify given texts as translation. It thus provides a new understanding of the
nature of translation enhanced by elements of Chinese philosophy and culture.
Reverse bandgap-bowing in nickel-cadmium sulfide alloys (Ni1−x
Cd
x
S) and its origin
Authors: Paramanik Subham , Chatterjee Soumyo , Pal Amlan J
Published: February 2021

We present evolution of band energies in α-NiS when alloyed with a cationic doping through isovalent cadmium (Cd2+). Optical bandgap of nickel-cadmium sulfide (Ni1−x
Cd
x
S) alloys, as a deviation from the linear relationship or Vegard’s law, have exhibited a reverse bandgap-bowing in the form of downward-concave dependence. Such a phenomenon, which manifests as a negative value of bowing coefficient (b), is uncommon in chalcogenide alloys. In this work, we have deliberated on the origin of reverse bandgap-bowing in nickel-cadmium alloys and identified the band responsible for the bowing phenomenon. While thin-films of the alloys were formed through successive ionic layer adsorption and reaction method, tunnel conductance and thereby density of states of the materials were derived from scanning tunneling spectroscopy. The spectroscopy provided the variation of conduction and valence band-edges (CB and VB, respectively) with respect to the cadmium-content in Ni1−x
Cd
x
S. The CB-edge of the alloys could be seen to remain mostly unaffected with increasing cadmium-content, since the band is composed of only the S 2p orbitals; the VB-energy, on the other hand, which forms due to an effective coupling between the metal d and the anion p orbitals, could be seen to be affected due to a p–d repulsion. Based on our experimental findings, we inferred that an antagonism between volume deformation and structural relaxation had resulted in the reverse bandgap-bowing in Ni1−x
Cd
x
S alloys.
Constructing a capacitive rotating angle sensing system using a hand-made oscillator and testers
Authors: Sakon Takuo , Noissiki Sota , Yamazaki Junya
Published: February 2021

In this study, we develop a capacitive rotating angle sensing system using a hand-made 1 kHz oscillator, field-effect transistor (FET) amplifier, and tester through a physics experiment conducted in Ryukoku University. Physics majors of the university can study the fundamentals of electronics through this system because it uses electronic elements, such as transistors and FETs. We fabricated the circuit of a rotation angle sensor system using a fan-type and coaxial variable capacitor. The capacitance of the variable capacitors varied linearly with the rotation angle. Owing to the CR high-pass filter, constructed by capacitors and a 100 kΩ resistor, the output voltage of the system was linear with capacitors and the rotation angle. Not only can this system be used to teach university-level physics, but its applications could extend to various industries.