bluuebunny/crossref_metadata_2025 huggingface dataset:
Income analysis of integrated farming system of dairy cow breeding farm, earthworms (Lumbricus rubellus), andcitrus sinensis Valenciafarm. Case study in Dau District, Malang Regency, East Java, Indonesia
Authors: Akhiroh Puji , Hermanto  , Purboningrum Galih , Sase Mentari Bertha Septina , Prafitri Rizki
Published: January 2022

The integrated farming system between dairy cow breeding, earthworms (Lumbricus rubellus), and citrus (Citrus sinensis valencia) plantations provides regular income for farmers and sustainable farming. This research aims to analyze farmers’ income based on the integrated farming system that has been done on these three commodities. This study utilized quantitative and qualitative methods to analyze data. Data were collected through questionnaires to 15 farmers who are members of Gading Kulon Farmer Group in Dau District, Malang Regency, East Java, Indonesia followed by in-depth interviews with key respondents. The study showed that dairy cow breeding provided annual income which contributed up to 58% of household income. Meanwhile, earthworm farming provides weekly income and twice a year income for citrus farming. Depending on the land area, Earthworms farming contributed up to 10% of household income, and citrus plantation was 33%, depending on the land area owned by farmers. The average income of Dairy cow breeding was Rp. 163,308,000 per year; the Average Income of earthworms was Rp. 27,058,000 per year, and the average income of citrus plants was 92,480,000 per year. However, integrated farming of these commodities does not work well in the community due to farmers’ lack of land and capital. Moreover, most respondents indicated that they were interested only in citrus farming because it is easier compared to dairy cow breeding and earthworm farming. Good cooperation from various parties is needed to increase the importance of integrated farming with these three commodities for sustainable farming in Indonesia.
Using quail waste as an adsorbent on biogas quality
Authors: Aprilianty Aurelia , Manasikana Arina , Pinandita Eggi Pur , Fa’izah Shafa , Junus Mochammad , Nugroho Hary
Published: January 2022

The aim of this research is to determine the effect of coconut and mineral waste of quail as adsorbents on the biogas purity. This research was designed to use the Completely Randomized Design (CRD) method with 6 treatments and 4 replications and the significant influence will be tested using Duncan Test. The result form this research showed that the use of coconut waste and mineral waste of quail as adsorbents gives highly significant influence (P<0,01) to increase the CH4 gas concentration, highly significant influence (P<0,01) to decrease CO2 gas concentration, highly significant influence (P<0,01) to decrease gas pressure and highly significant influence (P<0,01) to increase gas flow rate on biogas purity. The conclusion of this research is the use of 100% of activated coal from coconut waste, the use of 50% of activated coal from coconut waste and 50% of mineral waste from quail waste as an adsorbent are able to increase the quality of biogas. However, it is lack of effectiveness due to inappropriate application of biogas purification. It is suggested to do physical activation for both adsorbents in order to avoid saturation of the adsorbent so those absorbents be able to adsorb optimally the impurities gases on biogas.
Design and experimental tests of an Imbert type downdraft gasifier prototype and clean-up system for small-scale biomass-based power generation
Authors: Mendonça Miguel , Mantilla Victor , Patela João , Silva Valter , Resende Fernanda
Published: January 2022

This paper addresses the design, development and experimental tests of a prototype of fuel gas generation system based on biomass gasification for small-scale applications, around 5 kW. It comprises the small scale downdraft gasifier and the gas cleaning system aiming to clean-up the producer gas to be used in the upstream Internal Combustion Engine (ICE). The design of the downdraft gasifier prototype follows the methodologies that have been reported on the available literature. However, since these methodologies apply to gasifiers with larger rated powers, the adopted methodology is based on the extrapolation of the main parameters used for larger gasifiers design. For runing the ICE the producer gas requires to have a specific gas composition with an acceptable range of impurities. Therefore, a clean-up system was proposed following three stages: in first instance a hot gas clean-up using a cyclone designed to eliminate particles and compounds; then a heat exchanger was used for cooling the gas to condensate tars and water; finally a cold gas clean-up is performed by filtration using two filter steps: the first one using organic material (biomass) and the second one using a polypropylene cartridge filter. Experimental tests were performed using the developed imbert downdraft gasifier prototype, using pellets as feedstock. The preliminary results allow verifying several drawbacks that will difficult an effective integration of the developed prototype for small scale power generation applications based on ICE using low density feedstock.
Can Hybrid Synapse be Formed between Rat Spinal Motor Neurons and Major Pelvic Ganglion Neurons in vitro?
Authors: CHENG Shigang , XIANG Xuan , LV Zemin , MAO Xiaowen , YANG Xinghai
Published: January 2022

The purpose of this study is to determine whether synapses can be formed between spinal motor neurons (SMNs) and major pelvic ganglion (MPG) neurons of a rat in vitro. The green fluorescent protein (GFP)-labelled MPG cells were cultured together with SMNs in a specific medium. The synaptic-like contacts established between SMNs and MPG neurons were studied in co-cultures using morphologic and immunocytochemistry approaches. Phase-contrast observation of co-cultures showed apparent SMNs-MPG neurons contacts as early as three or four days in vitro. We demonstrate some evidence of synaptic contacts between SMNs and MPG neurons in vitro by immunostaining with antibody directed against postsynaptic density protein 95 (PSD-95). We describe the development process of a defined SMNs-MPG neurons co-culture system. The results suggest that the hybrid synapse formation that may occur between SMNs and MPG neurons in vitro played an essential role in the mechanisms of a regenerated bladder with an artificial somatic-autonomic reflex arc.
Preseason Symptom Reporting and Cognition in Middle School Athletes
with Past Concussions
Authors: Iverson Grant L. , Berkner Paul D. , Zafonte Ross , Maxwell Bruce , Terry Douglas P.
Published: January 2022

This study examined the association between past concussions and current
preseason symptom reporting and cognitive performance in 9,257 youth ages
11–13. Participants completed neurocognitive testing prior to
participating in a school sports between 2009 and 2019. We stratified the sample
by gender and number of prior concussions and assessed group differences on the
Post-Concussion Symptom Scale total score and the ImPACT cognitive composite
scores. Those with≥2 prior concussions reported more symptoms than those
with 0 concussions (d=0.43–0.46). Multiple regressions examining
the contribution of concussion history and developmental/health history
to symptom reporting showed the most significant predictors of symptoms scores
were (in descending order): treatment for a psychiatric condition, treatment for
headaches, history of learning disability (in boys only), history of
attention-deficit/hyperactivity disorder, and age. Concussion history
was the weakest statistically significant predictor in boys and not significant
in girls. Cognitively, boys with 1 prior concussion had worse speed those with 0
concussions (d=0.11), and girls with≥2 prior concussions had
worse verbal/visual memory than girls with 0 concussions
(ds=0.38–0.39). In summary, youth with≥2 prior
concussions reported more symptoms than those with no concussions. Boys with
multiple concussions performed similarly on cognitive testing, while girls had
worse memory scores.
Aus den Augen, aus dem Sinn – Knacknuss-Anamnese bei disseminierten Arzneimittelexanthemen auf „vergessene“ Selbstmedikation
Authors: Bircher Andreas J. , Imhof-Gex-Collet Caroline , Scherer Hofmeier Kathrin
Published: January 2022

Es werden zwei Patienten vorgestellt, die zur Abklärung unklarer Exantheme zugewiesen wurden, bei beiden wurde die Diagnose initial nicht gestellt. Der erste Patient hatte ein ausgeprägtes Arzneimittelexanthem, die Patientin ein generalisiertes fixes Arzneimittelexanthem. Die wegen Verdacht auf Arzneimittelallergie durchgeführte aufwändige allergologische Diagnostik fiel zunächst unergiebig aus. Bei beiden wurde initial der Auslöser anamnestisch nicht erfasst, da die Patienten die Selbsttherapie mit frei verkäuflichen Medikamenten vergessen hatten oder als nicht relevant betrachteten. Erst auf intensive Befragung konnten die Auslöser Pseudoephedrin bzw. Paracetamol eruiert und bestätigt werden. Die zentrale Rolle einer umfassenden Anamneseerhebung und Dokumentation aller eingenommenen Therapeutika wird dargestellt.
Snare tip soft coagulation (STSC) after endoscopic mucosal resection (EMR) of large (> 20 mm) non pedunculated colorectal polyps: a systematic review and meta-analysis
Authors: Chandan Saurabh , Facciorusso Antonio , Ramai Daryl , Deliwala Smit , Mohan Babu P. , Kassab Lena L. , Draganov Peter V. , Othman Mohamed O. , Kochhar Gursimran S.
Published: January 2022

Background and study aims Endoscopic mucosal resection (EMR) of laterally spreading tumors (LSTs) > 20 mm in size can be challenging. Piecemeal EMR of these lesions results in high rates of adenoma recurrence at first surveillance colonoscopy (SC1). Snare tip soft coagulation (STSC) of post resection margins is a safe and effective technique to prevent adenoma recurrence. We conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of this technique.

Patients and methods Multiple databases were searched through April 2021 for studies that reported on outcomes of post EMR STSC for LSTs > 20 mm in size. Meta-analysis was performed to determine pooled odds of adenoma recurrence as well as pooled proportion of adverse events including intraprocedural and delayed bleeding as well as intraprocedural perforation events.

Results Six studies including two randomized controlled trials (RCT) and four cohort studies with 2122 patients were included in the final analysis. Overall pooled odds of adenoma recurrence at SC1 with post EMR STSC compared to no STSC was 0.27 (95 % 0.18–0.42; I2 = 0 %), P < 0.001. Pooled rate of adenoma recurrence at SC1 in post EMR STSC cohort was 6 %. Rates of intraprocedural bleeding, delayed bleeding and intraprocedural perforation were 10.3 %, 6.5 % and 2 % respectively.

Conclusions Our results show that thermal ablation of resection margins with STSC in LSTs > 20 mm is a safe and effective technique in reducing the incidence of adenoma recurrence.
Diagnostic ability of linked color imaging in ultraslim endoscopy to identify neoplastic lesions in the upper gastrointestinal tract
Authors: Haruma Ken , Kato Mototsugu , Kawada Kenro , Murao Takahisa , Ono Shoko , Suehiro Mitsuhiko , Hori Shinichiro , Sasaki Fumisato , Koike Tomoyuki , Kitamura Shinji , Dohi Osamu , Kanzaki Hiromitsu , Yagi Nobuaki , Hashiguchi Keiichi , Oka Shiro , Katada Kazuhiro , Shimoda Ryo , Mizukami Kazuhiro , Takeuchi Toshihisa , Katsuki Shinichi , Tsuda Momoko , Naito Yuji , Kawano Tatsuyuki , Mori Keita , Ishikawa Hideki
Published: January 2022

Background and study aims Linked color imaging (LCI) is a new image-enhancing technique that facilitates the differentiation of slight differences in mucosal color tone. We performed an exploratory analysis to evaluate the diagnostic capability of LCI in ultraslim endoscopy, using data from patients examined in the LCI-Further Improving Neoplasm Detection in upper gastrointestinal (LCI-FIND) trial, a large-scale, multicenter, randomized controlled trial that demonstrated the capability of LCI for detecting neoplastic lesions in the upper gastrointestinal tract.

Patients and methods Data from the LCI-FIND prospective trial were used. In the LCI-FIND trial, 1502 patients with a history of gastrointestinal cancer were randomly assigned to two groups based on examination methods: white light imaging (WLI) followed by LCI (WLI group) and LCI followed by WLI (LCI group). The present exploratory analysis investigated the outcomes of patients who underwent ultraslim and standard endoscopies.

Results Ultraslim endoscopes were used in 223 patients and standard endoscopes in 1279 patients. The primary endpoint of the LCI-FIND trial was the percentage of patients diagnosed with a neoplastic lesion using WLI or LCI. The corresponding percentage tended to be higher with LCI than with WLI among patients who underwent ultraslim endoscopy and among those who underwent standard endoscopy; the crude risk ratio was 2.21 [95 % confidence interval (CI): 1.06–4.67], and the adjusted odds ratio was 2.46 (95 % CI: 1.07–5.63).

Conclusions Our exploratory analysis of data from the LCI-FIND trial showed that LCI is useful in identifying neoplastic lesions, when used in ultraslim endoscopy.
Rare Presentation of Limb–Body Wall Complex in a Neonate: Case Report and Review of Literature
Authors: Adeleke Omoloro , Gill Farrukh , Krishnan Ramesh
Published: January 2022

The limb–body wall complex (LBWC) aka body stalk syndrome is an uncommon congenital disorder characterized by severe malformations of limb, thorax, and abdomen, characterized by the presence of thoracoschisis, abdominoschisis, limb defects, and exencephaly. This condition is extremely rare with an incidence of 1 per 14,000 and 1 per 31,000 pregnancies in large epidemiologic studies. Majority of these malformed fetuses end up with spontaneous abortions. We present this rare case with occurrence in a preterm infant of 35 weeks' gestation. Our report highlights majority of the clinical presentations as reported in previous literature, but the significant pathological findings of absent genitalia and malformed genitourinary as well as anorectal malformations make this case presentation an even more rare occurrence. Infant karyotyping was normal male and there is no specific underlying genetic correlation in this condition which has a fatal prognosis.
Differential Diagnoses of Diseases Involving the Extrinsic Ocular Musculature – A Pictorial Essay
Authors: Santana Larissa Marques , Martins Larissa de Aguiar , Rosa-Júnior Marcos
Published: January 2022

Introduction There are some inflammatory, infectious, and neoplastic diseases affecting the extrinsic orbital musculature (EOM) that present with pain, decreased visual acuity, and proptosis. Imaging is fundamental to the differential diagnoses of these diseases with similar clinical presentations. The present case series report has as main objective to illustrate and discuss the main pathologies that affect the orbit.

Material and Methods The present series of cases discusses the main pathologies that can affect the extraocular musculature that can be characterized by computed tomography (CT) or magnetic resonance imaging (MRI) using cases from our institution.

Results and Discussion The present study compiled several cases of ophthalmopathy from our institution to illustrate and address some of these pathologies, such as orbital lymphoma, Grave disease, metastases, periorbital cellulitis, and idiopathic orbital inflammatory syndrome. The diseases are discussed according to the presentation of clinical cases with emphasis on the main imaging findings of each pathology.

Conclusion Computed tomography and MRI can help in the diagnosis and follow-up of the diseases that affect the EOM. We must be conversant with the main characteristics of the pathologies presented in the present case series report, since such findings together with clinical data can confirm the diagnosis of these diseases or at least help to narrow the differential diagnoses.
Sclerotherapy of Symptomatic Nonparasitic Splenic Cysts: Excellent Long-Term Treatment Response'
Authors: Dölle Michael , Wedemeyer Heiner , Gebel Michael , Potthoff Andrej , Zender Steffen
Published: January 2022

Background Splenic cysts are rare and occur in 0.5 to 2% of the population. They are usually asymptomatic and do not require therapy. In case of symptomatic nonparasitic splenic cysts, potential therapy includes partial splenectomy or laparoscopic cyst de-roofing as well as ultrasound-guided sclerotherapy with 1% polidocanol or 10% sodium chloride (NaCl) as an interventional alternative. So far, single-session sclerotherapy of symptomatic nonparasitic cysts is recommended only if clear-transparent cyst fluid is aspirated.

Materials and Methods We report a case series of 17 patients with symptomatic macroscopically turbid nonparasitic splenic cyst fluid who underwent ultrasound-guided fine needle sclerotherapy with either polidocanol ± 10% NaCl (n = 12) or 10% NaCl alone (n = 5) and a follow-up of a maximum of 12 years after first intervention. Clinical, sonographic, and laboratory chemistry data were recorded at baseline and during the follow-up.

Results The mean follow-up time was 43.65 ± 40.18 months. At the end of the follow-up, a 79% reduction of cyst size was achieved. The maximum size reduction in the polidocanol group was 76 ± 18% and 84 ± 21% in the sodium chloride group (p >0.05). At the end of follow-up, 15 out of the 17 patients did not have any further symptoms. Despite the cystic fluid being turbid, it was hardly possible to detect a microbiological superinfection.

Conclusion Sclerotherapy of splenic cysts leads to a significant size regression in all patients, independent of the sclerotherapy agent used with fewer systemic toxic side effects of polidocanol treatment. It was shown that in a tertiary care center with significant experience, sclerotherapy of splenic cysts is also safe and successful and can lead to a drastic regression of cyst size and symptoms. This shows that interventional therapy is a good alternative to surgical procedures.
A revised taxonomy for
Authors: Meade Conor V. , Parnell John A. N.
Published: January 2022

This paper presents a revision of Uvaria L. (Annonaceae) in continental Asia and outlying islands, north of the Thailand–Malaysia border, on the basis of a combination of new morphological analyses and recent phylogenetic data. Two new taxonomic groupings are defined within the genus in Asia on the basis of detailed morphological character analysis in ~1800 specimens. Stamen and carpel structure are shown to be significantly more informative than calyx and corolla characters for subgeneric differentiation, and reliably discriminate basal and derived radiations when mapped onto recent molecular phylogenies for the genus in Asia. Thirty-three species and species varieties are recognised within Uvaria in continental Asia, incorporating taxa formerly assigned to Anomianthus Zoll., Cyathostemma Griff., Ellipeia Hook.f. & Thomson, Ellipeiopsis R.E.Fr. and Dasoclema J.Sinclair. Four new combinations are proposed, and outstanding taxonomic, nomenclatural and typification issues are resolved for included taxa. Keys for both flowering and fruiting material are included, and distribution data are provided for all taxa.
Volatile-consuming reactions fracture rocks and self-accelerate fluid flow in the lithosphere
Authors: Uno Masaoki , Koyanagawa Kodai , Kasahara Hisamu , Okamoto Atsushi , Tsuchiya Noriyoshi
Published: January 2022

Significance

Hydration and carbonation are the main reactions that drive volatile cycles in the Earth. These reactions are characterized by a large increase in solid volume, by up to several tens of percent, and may induce fracturing, fluid flow, and further reactions. However, no experimental studies have succeeded in a clear increase in fluid flow during the reactions, and the mechanisms that control acceleration or deceleration remain largely unknown. We present here clear experimental evidence that hydration reactions can fracture rocks and accelerate fluid flow, under confining pressure (i.e., at simulated depth). We conclude that a high reaction rate, relative to the fluid flow rate, is essential for fracturing and accelerated fluid flow during these reactions in the Earth.
Convergence in the Malabar
Authors: Cardoso Hugo C.
Published: January 2022

The Indo-Portuguese creole languages that formed along the former Malabar Coast of southwestern India, currently
seriously endangered, are arguably the oldest of all Asian-Portuguese creoles. Recent documentation efforts in Cannanore and the
Cochin area have revealed a language that is strikingly similar to its substrate/adstrate Malayalam in several fundamental domains
of grammar, often contradicting previous records from the late 19th-century and the input of its main lexifier, Portuguese. In
this article, this is shown by comparing Malabar Indo-Portuguese with both Malayalam and Portuguese with respect to features in
the domains of word order (head-final syntax and harmonic syntactic patterns) and case-marking (the distribution of the oblique
case). Based on older records and certain synchronic linguistic features of the Malabar Creoles, this article proposes that the
observed isomorphism between modern Malabar Indo-Portuguese and Malayalam has to be explained as the product of either a gradual
process of convergence, or the resolution of historical competition between Dravidian-like and Portuguese-like features.
Self-interactions can stabilize excited boson stars
Authors: Sanchis-Gual Nicolas , Herdeiro Carlos , Radu Eugen
Published: January 2022

We study the time evolution of spherical, excited (i.e. nodeful) boson star (BS) models. We consider a model including quartic self-interactions, controlled by a coupling Λ. Performing non-linear simulations of the Einstein-(complex)–Klein–Gordon system, using as initial data equilibrium BSs solutions of that system, we assess the impact of Λ in the stability properties of the BSs. In the absence of self-interactions (Λ = 0), we observe the known behaviour that the excited stars in the (candidate) stable branch decay to a non-excited star without a node; however, we show that for large enough values of the self-interactions coupling, these excited stars do not decay (up to timescales of about t ∼ 104). The stabilization of the excited states for large enough self-interactions is further supported by evidence that the nodeful states dynamically form through the gravitational cooling mechanism, starting from dilute initial data. Our results support the healing power (against dynamical instabilities) of self-interactions, recently unveiled in the context of the non-axisymmetric instabilities of spinning BSs.
Acoustic metamaterials and metasurfaces composed of meta-atoms and meta-molecules
Authors: Ding Changlin , Dong Yibao , Wang Yuanbo , Shi Jianbing , Zhai Shilong , Zhao Xiaopeng
Published: January 2022

Acoustic metamaterials (AMMs) and acoustic metasurfaces (AMSs) are artificially structured materials with unique properties not found in natural materials. We review herein the properties of AMMs and AMSs that have been designed using different kinds of meta-atoms or meta-molecules with local resonance. AMMs composed of meta-atoms display a transmission dip with a negative modulus or a negative mass density. AMMs composed of two kinds of meta-atoms present a transparent transmission, indicating that they simultaneously have a negative modulus and a negative mass density. Furthermore, meta-molecule AMMs also exhibit double-negative properties. Moreover, acoustic meta-atoms or meta-molecules can be used to fabricate acoustic topological metamaterials with topologically protected edge state propagation. These meta-atoms and meta-molecules can also attain phase discontinuity near the resonant frequency, and thus they can be used to design AMSs with anomalous manipulation for acoustic waves. The tunability of meta-molecules provides a feasible path to achieve broadband AMS.
Green synthesis of novel in situ micro/submicron-Cu paste for semiconductor interconnection
Authors: Zhang Yu , Liu Qiang , Liu Yu , Tong Jin , Huang Zhongwei , Wu Song , Liang Peilin , Yang Guannan , Cui Chengqiang
Published: January 2022

A green method for the synthesis of in situ Cu paste is developed. Cu particles are prepared through chemical reduction by selecting a special copper source, reducing agent, and solvent. Then the reaction solution is directly concentrated to obtain an in situ Cu paste. The synthesis of Cu particles and the preparation of Cu paste are conducted simultaneously, and the process of separation, purification, drying, storage, and re-dispersion of powder are reduced. Particles are not directly exposed to air, thus the oxidation of micro/submicron -Cu is effectively prevented, and the agglomeration of particles caused by drying and dispersion operations is simultaneously reduced. Furthermore, the proposed method has a certain universality, and different types of Cu sources can be used to prepare in situ paste with different sizes and morphologies. The entire preparation process is simple, efficient, green, and the yield can reach 99.99%, which breaks through the bottleneck of the application of traditional micro/submicron-Cu materials. Copper acetate-based in situ paste is sintered for 30 min at 260 °C and 2 MPa in a reducing atmosphere. The shear strength, resistivity, and thermal conductivity reach 55.26 MPa, 4.01 × 10–8 Ω·m, and 92.75 W/(m·K), respectively, which could meet the interconnection application of power semiconductor devices.
Dispersion-assisted tunable fluorescence from carbon dots
Authors: He Qian , Ren Junkai , Liu Yaodong
Published: January 2022

In this study, carbon dots (CDs) synthesized by hydrothermal method with amino-rich surface exhibit tunable fluorescence across entire visible range by simply controlling the concentration. A comprehensive comparison has been performed for the first time between concentration-induced aggregation of the single-type CDs and electrostatic-induced agglomeration of opposite-charged CDs in terms of their fluorescence properties. Experimental results show that both the aggregation of CDs and internal absorption filtration are possible causes of the concentration-dependent fluorescence emission. Subsequently, the inter distance of adjacent CDs in their aggregates was enlarged by forming rigid double-stranded DNA (dsDNA) between adjacent CDs through base pairing. It is clear that the contact of CDs induces the changes of fluorescence emission and light absorption. Through a better understanding of the mechanisms behind concentration-induced multicolor emission, this work can provide a novel strategy to develop the advanced applications of CDs.
A review of the advances in composites/nanocomposites for triboelectric nanogenerators
Authors: Zhang Renyun , Örtegren Jonas , Hummelgård Magnus , Olsen Martin , Andersson Henrik , Olin Håkan
Published: January 2022

Material development is essential when studying triboelectric nanogenerators (TENGs). This importance is because the performance of TENGs is highly dependent on the properties of the utilized triboelectric materials. To obtain more specific properties, composites have been developed that combine the features of their components. According to Google Scholar, 55% of published papers related to triboelectric nanogenerators have utilized or mentioned composites. This number is 34.5% if one searches with the keyword nanocomposites instead of composites. The importance of composites is because they can exhibit new dielectric properties, better mechanical strength, enhanced charge affinities, etc. Therefore, the development of new composites has great importance in TENG studies. In this paper, we review the production of nanocomposites, the types of nanocomposites, and their application in TENG studies. This review gives an overview of how nanocomposites boost the performance of TENGs and provides guidance for future studies.
High-efficiency 2D nanosheet exfoliation by a solid suspension-improving method
Authors: Zheng Xuewen , Cong Haifeng , Yang Ting , Ji Kemeng , Wang Chengyang , Chen Mingming
Published: January 2022

Two-dimensional (2D) materials with mono or few layers have wide application prospects, including electronic, optoelectronic, and interface functional coatings in addition to energy conversion and storage applications. However, the exfoliation of such materials is still challenging due to their low yield, high cost, and poor ecological safety in preparation. Herein, a safe and efficient solid suspension-improving method was proposed to exfoliate hexagonal boron nitride nanosheets (hBNNSs) in a large yield. The method entails adding a permeation barrier layer in the solvothermal kettle, thus prolonging the contact time between the solvent and hexagonal boron nitride (hBN) nanosheet and improving the stripping efficiency without the need for mechanical agitation. In addition, the proposed method selectively utilizes a matching solvent that can reduce the stripping energy of the material and employs a high-temperature steam shearing process. Compared with other methods, the exfoliating yield of hBNNSs is up to 42.3% at 150 °C for 12 h, and the strategy is applicable to other 2D materials. In application, the ionic conductivity of a PEO/hBNNSs composite electrolytes reached 2.18 × 10−4 S cm−1 at 60 °C. Overall, a versatile and effective method for stripping 2D materials in addition to a new safe energy management strategy were provided.
Healing plasma current ramp-up by nitrogen seeding in the full tungsten environment of WEST
Authors: Maget P , Manas P , Artaud J-F , Bourdelle C , Bucalossi J , Bufferand H , Ciraolo G , Desgranges C , Devynck P , Dumont R , Fedorczak N , Felici F , Goniche M , Guillemaut C , Guirlet R , Gunn J P , Loarer T , Morales J , Sauter O , Van Mulders S , Vézinet D
Published: January 2022

Achieving a successful plasma current ramp-up in a full tungsten tokamak can be challenging due to the large core radiation (and resulting low core temperature) that can be faced with this heavy metallic impurity if its relative concentration is too high. Nitrogen injection during the plasma current ramp-up of WEST discharges greatly improves the core temperature and magnetohydrodynamic (MHD) stability. Experimental measurements and integrated simulations with the RAPTOR code, complemented with the QuaLiKiz neural network for computing turbulent transport, allow a detailed understanding of the mechanisms at play. Increased edge radiation during this transient phase is shown to improve confinement properties, driving higher core temperature and better MHD stability. This also leads to increased operation margins with respect to tungsten contamination.
Modelling of dust generation, transport and remobilization in full-metal fusion reactors
Authors: Ratynskaia S , Vignitchouk L , Tolias P
Published: January 2022

The design, licensing and operation of magnetic confinement fusion reactors impose various limitations on the amount of metallic dust particles residing inside the plasma chamber. In this context, predictive studies of dust production and migration constitute one of the main sources of relevant data. These are mainly conducted using dust transport codes, which rely on coupled dust-plasma and dust-wall interaction models, and require external input on the dust and droplet initial conditions. Some particularities of dust modelling in reactor-relevant conditions are analyzed with an emphasis on dust generation mechanisms relevant for disruption scenarios and on dust remobilization mechanisms relevant for ramp-up scenarios. Emerging topics such as dust production by runaway electron impact and pre-plasma remobilization of magnetic dust are also discussed.
Dynamics of bipolar HiPIMS discharges by plasma potential probe measurements
Authors: Zanáška Michal , Lundin Daniel , Brenning Nils , Du Hao , Dvořák Pavel , Vašina Petr , Helmersson Ulf
Published: January 2022

The plasma potential at a typical substrate position is studied during the positive pulse of a bipolar high-power impulse magnetron sputtering (bipolar HiPIMS) discharge with a Cu target. The goal of the study is to identify suitable conditions for achieving ion acceleration independent on substrate grounding. We find that the time-evolution of the plasma potential during the positive pulse can be separated into several distinct phases, which are highly dependent on the discharge conditions. This includes exploring the influence of the working gas pressure (0.3–2 Pa), HiPIMS peak current (10–70 A corresponding to 0.5–3.5 A cm−2), HiPIMS pulse length (5–60 μs) and the amplitude of the positive voltage U
+ applied during the positive pulse (0–150 V). At low enough pressure, high enough HiPIMS peak current and long enough HiPIMS pulse length, the plasma potential at a typical substrate position is seen to be close to 0 V for a certain time interval (denoted phase B) during the positive pulse. At the same time, spatial mapping of the plasma potential inside the magnetic trap region revealed an elevated value of the plasma potential during phase B. These two plasma potential characteristics are identified as suitable for achieving ion acceleration in the target region. Moreover, by investigating the target current and ion saturation current at the chamber walls, we describe a simple theory linking the value of the plasma potential profile to the ratio of the available target electron current and ion saturation current at the wall.
Memristive devices based on single ZnO nanowires—from material synthesis to neuromorphic functionalities
Authors: Milano G , Boarino L , Valov I , Ricciardi C
Published: January 2022

Memristive and resistive switching devices are considered promising building blocks for the realization of artificial neural networks and neuromorphic systems. Besides conventional top-down memristive devices based on thin films, resistive switching devices based on nanowires (NWs) have attracted great attention, not only for the possibility of going beyond current scaling limitations of the top-down approach, but also as model systems for the localization and investigation of the physical mechanism of switching. This work reports on the fabrication of memristive devices based on ZnO NWs, from NW synthesis to single NW-based memristive cell fabrication and characterization. The bottom-up synthesis of ZnO NWs was performed by low-pressure chemical vapor deposition according to a self-seeding vapor-solid (VS) mechanism on a Pt substrate over large scale (∼cm2), without the requirement of previous seed deposition. The grown ZnO NWs are single crystalline with wurtzite crystal structure and are vertically aligned respect to the growth substrate. Single NWs were then contacted by means of asymmetric contacts, with an electrochemically active and an electrochemically inert electrode, to form NW-based electrochemical metallization memory cells that show reproducible resistive switching behaviour and neuromorphic functionalities including short-term synaptic plasticity and paired pulse facilitation. Besides representing building blocks for NW-based memristive and neuromorphic systems, these single crystalline devices can be exploited as model systems to study physicochemical processing underlaying memristive functionalities thanks to the high localization of switching events on the ZnO crystalline surface.
Numerical and experimental analysis on the helicopter rotor dynamic load controlled by the actively trailing edge flap
Authors: Zhou Z X , Huang X C , Tian J J , Hua H X , Tang M , Wang C
Published: January 2022

Reducing the rotor dynamic load is an important issue to improve the performance and reliability of a helicopter. The control mechanism of the actively controlled flap (ACF) on the rotor dynamic load is numerically and experimentally investigated by a 3-blade helicopter rotor in this paper. In the aero-elastic numerical approach, the complex motion of the rotor such as the stretching, bending, torsion and pitching of the blade including the deflection of the ACF are all taken into consideration in the structural formulation. The aerodynamic solution adopted the vortex lattice method combined with the free wake model, in which the influence of ACF on the free wake and the aerodynamic load on the blade is taken into account as well. While the experimental method of measuring hub loads and acoustic was accomplished by a rotor rig in a wind tunnel. The result shows that the 3/rev ACF actuation can reduce the 3ω hub load by more than 50% at maximum, which is significantly better than the 4/rev control. While 4/rev has greater potential to reduce blade vortex interaction (BVI) loads than 3/rev with µ = 0.15. Further mechanistic analysis shows that by changing the phase difference between the dynamic load on the flap and the rest of the blade, the peak load on the whole blade can be improved, thus achieving effective control of the hub dynamic load, the flap reaches the minimum angle of attack at 90∘–100∘ azimuth under best control condition; when the BVI load is perfectly controlled, the flap reaches the minimum angle of attack at 140∘ azimuth, and by changing the circulation of the wake, the intensity of BVI in the advancing side is improved. Moreover, an interesting finding in the optimal control of noise and vibration is that an overlap point exists on the motion patterns of the flap with different frequencies.
Mechanical properties and densification mechanism of powder-in-tube Ba
x
K1−x
Fe2As2 superconductors
Authors: Han Meng , Yao Chao , Zhang Xianping , Wang Dongliang , Dong Chiheng , Liu Cong , Huang He , Yang Peng , Guo Wenwen , Tu Chang , Liu Shifa , Liu Xinyuan , Zhang Qianjun , Zhang Zhihao , Xie Jianxin , Ma Yanwei
Published: January 2022

Ba
x
K1−x
Fe2As2 (BaK-122) iron-based superconductors (IBSs) have been considered to be promising for high-field applications. The transport J
c performance of BaK-122 wires and tapes is continuously enhanced by introducing advanced fabricating methods. The mass density of BaK-122 superconducting core in wires and tapes is important to the transport J
c performance and related to the mechanical behavior during preparation. In this work, the mechanical property parameters including Poisson’s ratio-density, yield strength-density, and elastic modulus-density of BaK-122 IBS powder were examined via uniaxial compression experiments. The density-dependent mechanical constitutive of BaK-122 was obtained for the first time. The relationship function between density and Vickers hardness of BaK-122 was established as HV0.05 = 0.0249ρ
5.332 based on the numerical simulation of hardness testing, and a method for characterizing the BaK-122 core density was developed. It had been found the sheath materials and preparation method have great influences on the stress state of the BaK-122 core, and then affect the density. The densification mechanism and corresponding improvement method were revealed to provide guidance for preparing high-density BaK-122 wires and tapes. Finally, the generalized relationship between density and the superconducting transport J
c was established according to lots of experimental data from multiple BaK-122 samples, which has confirmed the positive correlation of ρ
core and J
c. We comparatively discussed the various cold-work and heat-treatment processes used in our team for preparing the BaK-122 wires and tapes, and the critical factors affecting the transport performance were summarized.
Strongly localized states and giant optical absorption induced by multiple flat-bands in AA-stacked multilayer armchair graphene nanoribbons
Authors: Chen Xiongwen , Wang Qian , Wu Ping , Zhou Guanghui
Published: January 2022

We propose an AA-stacked multilayer graphene nanoribbon with two symmetrical armchair edges as a multiple flat-band (FB) material. Using the tight-binding Hamiltonian and Green’s function method, we find that the FBs are complete and merged into many dispersive bands. The FBs cause multiple strongly localized states (SLSs) at the sites of the odd lines in every sublayer and a giant optical absorption (GOA) at energy point 2t, where t is the electronic intralayer hopping energy between two nearest-neighbor sites. By driving an electric field perpendicular to the ribbon plane, the bandgaps of the FBs are tunable. Accordingly, the positions of the SLSs in the energy regime can be shifted. However, the position of the GOA is robust against such field, but its strength exhibits a collapse behavior with a fixed quantization step. On the contrary, by driving an electric field parallel to the ribbon plane, the completeness of FBs is destroyed. Resultantly, the SLSs and GOA are suppressed and even quenched. Therefore, such ribbons may be excellent candidates for the design of the controllable information-transmission and optical-electric nanodevices.
Natural inflation after Planck 2018
Authors: Stein Nina K. , Kinney William H.
Published: January 2022

We calculate high-precision constraints on Natural Inflation relative to current observational constraints from Planck 2018 + BICEP/Keck(BK15) Polarization + BAO on r and n
S, including post-inflationary history of the universe. We find that, for conventional post-inflationary dynamics, Natural Inflation with a cosine potential is disfavored at greater than 95% confidence out by current data. If we assume protracted reheating characterized by w̅>1/3, Natural Inflation can be brought into agreement with current observational constraints. However, bringing unmodified Natural Inflation into the 68% confidence region requires values of T
re below the scale of electroweak symmetry breaking. The addition of a SHOES prior on the Hubble Constant H
0 only worsens the fit.
Highly Sensitive, Non-cryogenic NIR High-resolution Spectrograph, WINERED
Authors: Ikeda Yuji , Kondo Sohei , Otsubo Shogo , Hamano Satoshi , Yasui Chikako , Matsunaga Noriyuki , Sameshima Hiroaki , Yoshikawa Tomohiro , Fukue Kei , Nakanishi Kenshi , Kawanishi Takafumi , Watase Ayaka , Nakaoka Tetsuya , Arai Akira , Kinoshita Masaomi , Kitano Ayaka , Nakamura Kazuki , Asano Akira , Takenaka Keiichi , Murai Taichi , Kawakita Hideyo , Minami Atsushi , Izumi Natsuko , Yamamoto Ryo , Mizumoto Misaki , Taniguchi Daisuke , Tsujimoto Takuji
Published: January 2022

WINERED is a novel near-infrared (NIR) high-resolution spectrograph (HRS) that pursues the highest possible sensitivity to realize high-precision spectroscopy in the NIR as in the optical wavelength range. WINERED covers 0.9–1.35 μm (z, Y, and J-bands) with three modes (Wide mode and two Hires modes) at the maximum spectral resolutions of R = 28,000 and R = 70,000. For fulfilling the objective, WINERED is designed with an unprecedentedly high instrument throughput (up to 50% at maximum including the quantum efficiency of the array) that is three times or more than other existing optical/NIR HRSs. This is mainly realized by a combination of non-white pupil and no fiber-fed configuration in optical design, the moderate (optimized) wavelength coverage, and the high-throughput gratings. Another prominent feature of WINERED is “warm” instrument despite for infrared (IR) observations. Such non-cryogenic (no cold stop) IR instrument finally became possible with the combination of custom-made thermal-cut filter of 10−8 class, 1.7 μm cutoff HAWAII-2RG array, and a cold baffle reducing the direct thermal radiation to the IR array into the solid angle of f/2. The thermal background is suppressed below 0.1 photons pixel−1 s−1 even in the wide band of 0.9–1.35 μm under the environment of 290 K. WINERED had been installed to the 3.58 m New Technology Telescope at La Silla Observatory, ESO, since 2017. Even with the intermediate size telescope, WINERED was confirmed to provide a limiting magnitude (for SNR = 30 with 8 hr. integration time) of J = 16.4 mag for the Wide mode and J = 15.1 mag for the Hires mode, respectively, under the natural seeing conditions. These sensitivities are comparable to those for the existing NIR-HRSs attached to the 8–10 m class telescopes with AO. WINERED type spectrographs may become a critical not only for the currently on-going extremely large telescopes to reduce the developing cost and time but also for smaller telescopes to extend their lives with long programs.
iSHELL: a 1–5 micron R = 80,000 Immersion Grating Spectrograph for the NASA Infrared Telescope Facility
Authors: Rayner John , Tokunaga Alan , Jaffe Daniel , Bond Timothy , Bonnet Morgan , Ching Gregory , Connelley Michael , Cushing Michael , Kokubun Daniel , Lockhart Charles , Vacca William , Warmbier Eric
Published: January 2022

iSHELL is a 1.06–5.3 μm high spectral resolution spectrograph built for the 3.2 m NASA Infrared Telescope Facility (IRTF) on Maunakea, Hawaii. Dispersion is accomplished with a silicon immersion grating in order to keep the instrument small enough to be mounted at the Cassegrain focus of the telescope. The white pupil spectrograph produces resolving powers of up to about R ≡ λ/δλ = 80,000 (0.″375 slit). Cross-dispersing gratings mounted in a tiltable mechanism allow observers to select different wavelength ranges and, in combination with a slit wheel and Dekker mechanism, slit widths ranging from 0.″375 to 4.″0 and slit lengths ranging from 5″ to 25″. One Teledyne 2048 × 2048 HAWAII-2RG array is used in the spectrograph, and one Raytheon 512 × 512 Aladdin 2 array is used in a 1–5 μm slit viewer for object acquisition, guiding, and scientific imaging. iSHELL has been in productive regular use on IRTF since first light in 2016 September. In this paper we discuss details of the science case, design, construction and astronomical use of iSHELL.
High-power ytterbium-doped fibre master-oscillator power-amplifier at 1018 nm
Authors: Park H M , Oh Y J , Park E J , Park J S , Jeong H , Kim J W
Published: January 2022

A high-power master-oscillator power-amplifier (MOPA) at 1018 nm employing ytterbium (Yb)-doped fibres as a gain medium is reported. Utilizing a diffraction grating as a reflector, we could successfully suppress the influence of the broadband amplified spontaneous emission on the master-oscillator or the power-amplifier, resulting in stable amplification of the laser signal at 1018 nm. Based on a simple theoretical simulation on gain spectra and experimental investigation on parasitic lasing thresholds, the Yb fibre MOPA constructed in-house yielded 220 W of output at 1018 nm with a beam propagation factor (M2) of 1.1. The prospects for further power scaling are considered.
Evaluation of Fano resonance and phase analysis of plasma induced transparency in photonic nanostructure based on equivalent circuit analysis
Authors: Feng Yanming , Li Zhiguo , Zhao Qiang , Chen Pingping , Wang Jiqing
Published: January 2022

Fano resonance and plasma induced transparency (PIT) have been widely observed in various plasmonic nanostructures. Fano resonance takes place in weak coupling regime where coupling constant between two electromagnetic modes is lower than damping constant of system. Hence, extracting coupling and damping coefficients from resonance spectrum is the key to distinguish between Fano resonance and other resonances. In this paper, we propose a simple and realizable coupled LC circuit to analyze Fano resonance and PIT. Weak and strong coupling regime are distinguished by comparing coupling constant with damping constant. Meanwhile, we gain deep insight into Fano resonance and PIT in circuit by analyzing circuit phase and understand their connection with resonance in photonic structure. Furthermore, we extend the equivalent circuit model to the field involved short-range plasmon polarization or multi-orders dark modes. Since there are no specific parameters associated with photonic nanostructure, the proposed equivalent circuit can be used in most plasmonic resonance system as an universal model.