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This work shows that the cup-stacked carbon nanotube/carbon fiber felt composite electrode (CSCNT/felt) is a promising electronic conductive matrix to develop biosensors. The device was prepared by...

In the present study, the in vitro antifungal potential of seven Lamiaceae herbs against Fusarium oxysporum f. sp. cyclaminis were investigated. On the basis of the results, the in vivo antifungal effects of sage water extract on Fusarium wilt in cyclamen were evaluated, and the antifungal properties of the extract were identified. Among the seven herbs, sage water extract (0.5% and 2%, w/v) showed considerable suppression of F. oxysporum f. sp. cyclaminis in vitro. For the in vivo evaluation, cyclamen plants were treated with sage water extract (20%, w/v) two times and inoculated with F. oxysporum f. sp. cyclaminis. Six weeks after the inoculation, a lower disease incidence and disease severity indices were observed in roots and shoots of the treated plants. These effects could be attributed to reduced Fusarium populations in the plant roots because of the fungistatic and fungicidal effects of the sage extract. Consequently, the dry weights of the shoots and roots treated with the sage extract were higher than those of the control. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) was performed, and caffeic acid and rosmarinic acid were identified to be important metabolites in the sage water extract. In addition, the antifungal effects of these compounds against F. oxysporum f. sp. cyclaminis were confirmed using an in vitro test. Thus, it can be concluded that sage water extract can suppress Fusarium wilt in cyclamen and the two identified compounds play key roles in the antifungal properties of sage.

The heat treatment behavior of semi-multi-alloyed white cast iron with relatively lower carbide-forming elements compared with regular multi-alloyed white cast iron was investigated. The semi-multi-alloyed white cast iron with carbon balance (Cbal) of − 0.68 to + 0.53 wt% was prepared by varying chromium (Cr) content from around 3–9 wt% under the fixed contents of 2 wt% molybdenum (Mo), 1 wt% tungsten (W) and 5 wt% vanadium (V). After annealing, the test specimens were hardened after austenitizing at 1050 °C and 1100 °C. The tempering was carried out between 400 and 600 °C. In as-hardened state, the macro-hardness and micro-hardness increased greatly as the Cbal rose from − 0.68 to − 0.01 wt% and then decreased gradually with an increase in the Cbal value. The volume fraction of retained austenite (Vγ) increased continuously as the Cbal increased, and more Vγ was obtained in the case of hardening from higher austenitizing temperature. In tempered state, the hardness curve showed an evident secondary hardening due to the precipitation of fine secondary carbides during holding and the transformation of retained austenite to martensite during post-cooling. The maximum tempered macro-hardness (HTmax) was obtained by tempering at 500–550 °C. The highest values, 862 HV30 and 795 HV0.1, were obtained in the specimen with − 0.01 wt%Cbal where the Vγ was about 2%. As the Cbal value increased, the maximum tempered micro-hardness (HTmax-M) increased remarkably toward − 0.01 wt%Cbal and then it decreased regardless of austenitizing temperature. At the same Cbal value, the HTmax-M of specimens hardened from 1100 °C were larger than those hardened from 1050 °C. It was found that the 10–50% Vγ in as-hardened state was necessary to obtain hardness over 800 HV30 and 750 HV0.1 by tempering. The degree of secondary hardening (ΔHs) increased with an increase in the Cbal and the Vγ in the as-hardened state.

A new High-Temperature Superconducting ECR (HTS-ECR) ion source is under development in Research Center for Nuclear Physics (RCNP), Osaka University. This ion source will be used for production of high intensity proton, deuteron and He ion beams. The HTS-ECR magnets are composed of three solenoid coils and a set of sextupole coils made of REBCO tapes, a high-temperature superconductor. The HTS-ECR ion source is designed to operate at frequency of 2.45 GHz and 10 GHz. Performance test of the HTS coils had been carried out at 31 K and 77 K. This HTS coil technology will be applied to development of a meter-size HTS coil system of a high intensity compact AVF cyclotron. This paper introduces the basic design of the HTS-ECR ion source. The performance test results showed that REBCO solenoids remain superconducting state with a current up to 400 A. Simulation results of the magnetic field and electromagnetic field distributions in a plasma chamber fulfilled the requirements of electron cyclotron resonance conditions at 2.45 GHz and 10 GHz. Simulation result of mirror ratios and electromagnetic field amplitudes are also presented in this paper.

We investigate how Li intercalation into composite electrodes resulting from the combination of graphitic carbon felt (CF) with carbon nanotubes (CNTs) functionalized with electroactive nanoparticles (NPs) depends on NP concentration. To this end, we study CF electrodes coated or not with hydrophilic CNTs containing electrodeposited β/γ-MnO2NPs (wt% 25, 42, and 69) with hollow-nanotube structure. Galvanic coupling between the CNTs and the NPs is the reason why the electrochemical performance of CNT-NP nanocomposites varies with the NP concentration. The CNT coating on the CF electrode also avoids capacity fading of the CF/MnO2NP electrodes and prevents carbon fibers from interconnecting with SEI. More specifically, the CNTs stabilize the solid electrolyte interphase and prevent NP detachment, thereby producing electrodes with long-term cyclability. The best electrochemical performance occurs for CNT/MnO2NP mass wt% 25 (1114 mAh g−1, 1st discharge/charge Faradaic efficiency ~80% at 1 A g−1, cut-off potential = 4–0.005 V vs Li+/Li).

New composite based on polypyrrole (PPy) and bismuth oxide (α-Bi2O3) was investigated as supercapacitor electrode. The α-Bi2O3 was obtained by hydrothermal route at 500 ºC for 2 h. Cyclic voltammetry was used to electropolymerize PPy on graphite electrode (GE) or on GE/α-Bi2O3. The X-ray diffraction profile of Bi2O3 revealed the α-Bi2O3 monoclinic structure with space group P21/c.The scanning and transmission electron microscopy images showed that PPy coated α-Bi2O3. Raman spectra showed that PPy inhomogeneously coated α-Bi2O3, but it was still possible to obtain a α-Bi2O3 @PPy core-shell hybrid composite with highly ordered α-Bi2O3 with electronic interaction between the oxide and the polymer chain of the polymer. The GE/α-Bi2O3@PPy composite electrode (type I supercapacitor) displayed a predominantly capacitive profile with low impedance values and good electrochemical stability after 50 charge and discharge cycles. The specific capacitance of α-Bi2O3 @PPy composite was found in the range of 634 to 301 F g-1 to gravimetric current of 3 and 10 A g-1, respectively.

Binder-free electrodes resulting from nonwoven carbon fiber felt coated with carbon nanotubes (CNT/FELT) are a useful class of composites to explore the electrochemical properties of CNTs and derived nanostructures deposited on the CNT surface. Here, we show that, contrary to current literature knowledge, the nonwoven carbon fibers are not just a constituent of the CNT/FELT and do not have the exclusive function of holding the CNT network in the three-dimensional architecture. In fact, the nonwoven carbon fibers constituting the FELT and their electronic conductivity influence Li+ intercalation into the CNTs coating the FELT. By using FELT coated with cup-stacked-CNT (5% wt. CSCNT) and embedded with SWCNTs (CSCNT/FELTSWCNT) or MWCNTs (CSCNT/FELTMWCNT), we were able to tailor the Li specific capacity and Faradaic efficiency of the resulting electrode. From a technological standpoint, despite its huge specific surface area of around 1624 m2 g−1, CSCNT/FELTMWCNT presented excellent reversible Li specific capacity (415 mAh g−1) with respect to the total electrode mass as well as excellent faradaic efficiency at initial discharge/charge (~93%, C-rate ~ 1.6). Some kind of hybridization effect took place between the CNTs and the nonwoven carbon fibers in the FELT. Therefore, the CSCNT/FELT(SW or MW)CNT is a hybrid composite whose electrochemical behavior is governed by its constituents and their eventual electronic interaction.

Nanostructures for lithium intercalation can be obtained by combining carbon nanotubes with nanoparticles, to achieve a composite that can be applied as electrochemical energy storage device. Depending on the chemical composition and architecture of the nanostructure, it can be used to develop batteries, supercapacitors, or hybrid battery-supercapacitor devices. Here, we study how the V2O5.nH2O concentration affects lithium intercalation into the V2O5.nH2O/cup-stacked carbon nanotube (CSCNTs) nanostructure. First, CSCNTs were directly grown on the surface of a nonwoven carbon fiber felt (CF). Then, e/δ-V2O5.nH2O was electrodeposited on the CF/CSCNT composite. Between 4.2 and 1.5 V, 34 wt% V2O5.nH2O load provided lithium specific capacity of 633 mAhg−1 at 0.5 Ag−1 for 300 discharge/charge cycles with lower fading capacity. Higher or lower V2O5.nH2O load diminished this performance. Depending on the V2O5.nH2O load and scan rate, this new nanostructure can also operate as a pseudo-capacitor, to deliver 610 F g−1 at a scan rate of 10 mV s−1 between 4.0 and 1.5 V. We discuss this dependence in terms of V2O5.nH2O morphology and the presence of a junction between CSCNTs and V2O5.nH2O.

The quantum Hall effect is a macroscopic quantum phenomenon in a two-dimensional electron system. The two-dimensional electron system in SrTiO3 has sparked a great deal of interest, mainly because of the strong electron correlation effects expected from the 3d orbitals. Here we report the observation of the quantum Hall effect in a dilute La-doped SrTiO3-two-dimensional electron system, fabricated by metal organic molecular-beam epitaxy. The quantized Hall plateaus are found to be solely stemming from the low Landau levels with even integer-filling factors, ν=4 and 6 without any contribution from odd ν's. For ν=4, the corresponding plateau disappears on decreasing the carrier density. Such peculiar behaviours are proposed to be due to the crossing between the Landau levels originating from the two subbands composed of d orbitals with different effective masses. Our findings pave a way to explore unprecedented quantum phenomena in d-electron systems., Observation of quantum phenomena in correlated electron systems is challenging due to low mobility and high concentration of carriers. Here, Matsubara et al. report a two-dimensional electron system with high mobility-low carrier density in δ-doped SrTiO3, demonstrating quantum Hall effect in d-electron systems.

Amorphous V 2 O 5 .nH 2 O nanostructures (Ns) on CNTs coated/uncoated carbon fibre felt are very attractive electrodes for various electrochemical devices. In present article, we report the morphological and structural characterizations of electrodeposited V 2 O 5 .nH 2 O (denoted as δ -V 2 O 5 ) phase on defective CNTs coated/uncoated graphitic carbon fibre felt using micro-Raman scattering, TGA curves, SEM and XPS techniques. Using electrochemical methodology, we obtained a highly stable superficial hydrated V 2 O 5 .nH 2 O (n ∼ 0.5) Ns on the surface of bare carbon fibre felt and defective CNT/carbon fibre felt composite. The intercalated hydroxide/H 2 O bonds are stable till 350°C temperature on both CNTs coated/uncoated felt substrates, which can be extracted from V 2 O 5 .nH 2 O structure using high laser power ( ≥ 10 mW). After de-hydration of V 2 O 5 .nH 2 O Ns, the local structural phase inclined to e -V 2 O 5 . The surface morphological modification from flat to wrinkle like patterned of V 2 O 5 .nH 2 O Ns depends on electrodeposition parameters (current and time), while the CNT provokes the formation of a V 2 O 5 .nH 2 O layer on CNT/felt fibres with larger degree of roughness, hydration and thickness than in case of bare felt fibres. The proportion of oxidation-state (V + 5 ∕ + 4 ∕ + 3 ) is barely influenced by CNT presence. Moreover, the electrodeposited V 2 O 5 .nH 2 O layer on graphite felt occurs heterogeneously on the carbon fibre electrode surface, unlike CNT/felt. On the other hand, the crystallite size (L a ) of micrometric felt and CNT/felt with and without V 2 O 5 .nH 2 O nanostructures are calculated, demonstrating that the adherence of V 2 O 5 .nH 2 O Ns is better on CNT coated felt than bare felt surface, which improved the crystalline properties of nanocarbons as well.

Although traditional water treatment systems can remove various substances from wastewater, these conventional systems fail to remove many chemical molecules that pose potential ecological and health risks. Carbon nanotubes (CNTs) appear attractive to adsorption of many substances, but CNTs adsorbed with toxic substances becomes a nanocomposite still more toxic. Here, we employ zebrafish embryos as biosensor to examine how a hybrid micro/nanostructured carbonaceous material (HMNC) derived from a combination of activated carbon (AC) with hydrophilic carbon nanotubes (CNTs) can remediate wastewater contaminated with the pharmaceutical fluoxetine hydrochloride (FLX). AC and HMNC are practically non-toxic to zebrafish embryos (LC50 > 1000 mg.L−1). HMNC addition to culture medium containing FLX significantly reduces sublethal effects and lethality. Interaction between FLX and HMNC involves chemical adsorption such that embryo co-exposure to HMNC adsorbed with FLX in the range of concentrations evaluated herein does not elicit any behavioral changes in zebrafish.

Background The usefulness of re-sentinel node biopsy (re-SNB) is unclear in the management of patients with ipsilateral recurrent breast cancer. Methods We retrospectively reviewed 52 patients with locally recurrent breast cancer who underwent re-SNB from July 2012 to March 2019. Both radioactive colloid and indocyanine green were used in all cases. Results Forty-four patients were after SNB and 8 were after axillary lymph node dissection(ALND). SLNs were successfully visualized by lymphoscintigraphy in 94.2% (49/52) of cases (95.4% post-SNB vs. 87.5% post-ALND, Fisher’s exact test, p = 0.401). Among post-SNB patients with successful mapping, 50% had SLNs only in ipsilateral axilla(I) and 50% had at least one SLN in other regions(contralateral axilla [C] and/or parasternal region [P])with or without SLN in (I), compared to 28.6% and 71.4% in post-ALND cases respectively(p = 0.424). Among post-SNB cases with prior breast irradiation (n = 37), 44.4% had SLN only in (I) and 55.6% had at least one SLN in other regions, compared to 83.3% and 16.7% in cases without prior irradiation (n = 7) (p = 0.184), respectively. While these differences were not significant, a lower rate of visualization and higher frequency of aberrant lymphatic flow in post-ALND than those in post-SNB was noted, and prior irradiation might affect lymphatic flow. We tried re-SNB for 47 cases and SLNs were successfully removed in 45 (95.7%) patients (92.8% in post-SNB, 100% in post-ALND). Re-SNB for (I) was performed for all cases with hot spots in (I) and one case without hot spot. Re-SNB for (C) or (P) were decided based on physician’s judgment. The SLN identification rates by site were 92.1% (35/38) for (I), 90.0% (9/10) for (C), and 100% (3/3) for (P). Sentinel node metastasis was found in three cases, all of which were in (I). ALND was performed in one case with macrometastasis but was omitted in two cases with micrometastases. The median follow-up duration after re-SNB was 22 months and no recurrence was observed. Conclusions Sentinel node identification was possible with high detection rates among patients with recurrent breast cancer after prior breast-conserving and axillary surgery. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure T. Yamanaka: Honoraria (self): Chugai; Honoraria (self): Eisai; Honoraria (self): Novartis Pharma; Honoraria (self): Taiho; Honoraria (self): Phizer Japan. T. Yamashita: Honoraria (self), Research grant / Funding (institution): Chugai; Honoraria (self): Eisai; Honoraria (self): Novartis Pharma; Honoraria (self): Taiho; Honoraria (self), Research grant / Funding (institution): Nippon Kayaku; Honoraria (self): AstraZeneca; Honoraria (self), Research grant / Funding (institution): Kyowa kirin; Honoraria (self): Phizer Japan; Honoraria (self): Takeda. N. Suganuma: Honoraria (self): Eisai; Honoraria (self): Novartis Pharma; Honoraria (self): Taiho; Honoraria (self): Kyowa kirin; Honoraria (self): Phizer Japan. All other authors have declared no conflicts of interest.

By using a focused-ion-beam (FIB) method with Ga ions, we prepared quasi-one-dimensional (q-1D) In/Mo specimens with widths of ≈ 200 nm and ≈ 500 nm from two dimensional (2D) films deposited on a SiO2/Si substrate. We observed the superconducting transition of q-1D In/Mo, whose transition temperature Tc is higher than T c ≈ 3.6 K of a 2D In/Mo specimen on a glass substrate. For specimens fabricated using the FIB method, the element distributions analyzed by energy dispersive x-ray spectroscopy reveal Ga invasion into the q-1D In/Mo region. The gradually changing resistance of q-1D In/Mo at temperatures below Tc can be well explained by the thermal activation phase-slip model with T c = 5.1 K and coherence length ξ ( 0 ) ≈ 9.5 nm .

In the present study, we addressed the palladium (Pd) decoration of multiwalled carbon nanotube (CNT)/activated carbon (AC) hybrid composites (MWCNT/AC), and examined the catalytic behavior of the composites in the hydrogenation of trans-cinnamaldehyde. The MWCNT/AC composites were prepared by growing CNT network on the surface of AC granules, using the chemical vapor deposition method. XPS analysis revealed that the MWCNT/AC and COOH–MWCNT/AC composites and isolated AC adsorbed Pd at different oxidation states when dipped into a Pd0 microemulsion: isolated AC and the COOH–MWCNT/AC composite adsorbed Pd nanoparticles at di- and tetravalent states (Pd2+/4+), while the MWCNT/AC composite adsorbed Pd nanoparticles at zero and tetravalent states (Pd0/Pd4+). The MWCNT/AC composite may thereby have hierarchical Pd adsorption properties dependent on the MWCNT network type grown onto the AC surface. Regarding the catalytic performance, the (Pd0/4+)-MWCNT/AC catalyst displayed higher selectivity to hydrocinnamaldehyde formation (95.9%) when compared with the (Pd2+/4+)-AC and (Pd2+/4+)-COOH–MWCNT/AC catalysts (72.1% and 91.4% selectivity, respectively). The catalytic performance of the (Pd0/4+)-MWCNT/AC catalyst with 2.8 wt% of Pd loading was also superior than the catalytic performance of commercial catalysts with 5 and 10 wt% of Pd loading and other Pd/CNTs catalysts reported in the literature.