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The creation of three-dimensional (3D) geometrical shapes with atomically ordered surfaces and the investigation of their physical properties are major steps contributing to the development of a new paradigm in surface science. We produced a 3D-patterned Si sample with atomically flat and reconstructed {111} facet surfaces, and investigated its structural and physical properties. To apply the conventional techniques in surface science to 3D samples with various oriented surfaces, instead of two-dimensional planar samples, an appropriate relationship between the crystallographic surface ordering on the 3D-architected surfaces and the angle-resolved photoelectron spectroscopy (ARPES) setup considering the configuration in 3D space is indispensable. The distinctive and complex low-energy electron diffraction (LEED) patterns reflecting the 3D-arranged facet surfaces showed the realization of atomically reconstructed facet surfaces on 3D-patterned Si. Surface states of the 3D-patterned Si{111} surfaces are mapped by ARPES by considering the 3D geometrical relationship. The selection of the appropriate alignment of the incident electron beam (light) for the target surfaces allows the clear observation of the band dispersion from the produced {111}7×7 facet surfaces in 3D space. Our demonstration of accessibility of ARPES technique could provide useful guidelines for new methodologies, giving a fundamental understanding of 3D-shape-induced novel functionalities.

Spatially arranged surfaces on the micro-rod structure, which was three-dimensionally (3D) architected on a Si(110) substrate have been thoroughly investigated by a system with micro-beam reflection high-energy electron diffraction (μ-RHEED) and scanning electron microscopy (SEM). The combination of μ-RHEED and SEM realized analytical structure investigation of 3D surfaces with the spatial resolution of sub micrometer for the 3D rectangular shaped rod consisting of a (110) top surface (20 μm wide) and {111} vertical side surfaces (10 μm wide). Exhaustive mapping revealed the peculiar reconstructed surface structures: Si(110) “16 × 2” single domain and {35 47 7} facet surfaces locally appeared on the interconnected edge region on the 3D structure in addition to the “16 × 2” and 7 × 7 super structures on flat top (110) and side {111} surfaces, respectively. The formation mechanism for “16 × 2” single-domain structure near the corner edge of the (110) surfaces and {35 47 7} facets on the corner edges between (110) and {111} surfaces were discussed from the viewpoint of the surface stability on the 3D geometrical shaped Si structure.

The control of three-dimensional (3D) geometrical shapes is one of important approaches that contribute the development of new functionalities in material science. We produced 3D Si pyramids with a...

Protonation of perovskite rare-earth nickelate, typically NdNiO3, can introduce a metal-to-insulator transition at room temperature, which will benefit practical ion electronics applications. In this work, the proton diffusion in NdNiO3 is analyzed by electrochemical impedance spectroscopy and the activation energy of the proton diffusion is obtained. For a comprehensive analysis, the method of optical observation is further evaluated and it is proved to be a quick route to obtain diffusion coefficient and activation energy in real time and real space. This work would guide future research on the evaluation of protonated perovskite rare-earth nickelate with microscale structure design.

Vanadium dioxide (VO2) exhibits an insulator–metal transition (IMT) accompanied with a giant resistance change, which is attractive for the application of devices, such as switching devices. Since the behavior of individual domains determines the total IMT property of the VO2 sample, the steep resistance change from a single domain can be identified and utilized in a sample whose size is as small as the individual domain size. Uniquely, micro-structured VO2 thin films on hexagonal boron nitride (hBN) exhibit step resistance changes owing to the confined metallic domains. In this study, we demonstrated step electrical switching in the two-terminal VO2 sample produced on hBN. Operando structural and electric investigation revealed that the emergence of metallic domains in the micrometer space contributes to the step electric current increase. Our results indicate the use of individual metallic domains in VO2 thin films on hBN in the application of novel devices.

A transparent thermoelectric material requires not only high thermoelectric performance but also high optical transmittance. However, in transparent nanostructured thermoelectric materials, the nanostructure interface brings the trade-off relationship between thermal conductivity and optical transmittance. We propose an approach for the simultaneous control of thermal conductivity and optical transmittance in the epitaxial nanostructured films, where carriers can be smoothly transported. This is realized by the interface design based on the three strategies: (1) a large atomic mass difference at the heterointerface for low thermal conductivity; (2) heterointerface with almost the same refractive index and flat surface for high optical transmittance; and (3) epitaxial heterointerface for smooth carrier transport. We formed epitaxial ZnO/SnO2 multilayer films based on this design guideline. The multilayer films exhibit lower thermal conductivity and higher optical transmittance than an ever reported transparent nanostructured thermoelectric material. These results highlight that this design is promising to realize high-performance transparent nanostructured thermoelectric materials.

We investigate resistance switching in proton-memristive NdNiO3 film devices via the diffusional migration of a proton dopant by using electric field control. Lattice strain is found to play a significant role in determining proton migration within NdNiO3 thin film. Compressive strain can accelerate the migration, resulting in a switching efficiency of 28.22% which is significantly higher than 0.21% on a tensile-strained device. The results demonstrate the significance of strain engineering and will guide the development of the design of multifunctional perovskite devices for emerging iontronics memory and computing applications.

The electric-field-assisted hydrogenation and corresponding resistance modulation of NdNiO3 (NNO) thin-film resistors were systematically studied as a function of temperature and dc electric bias. Catalytic Pt electrodes serve as triple-phase boundaries for hydrogen incorporation into a perovskite lattice. A kinetic model describing the relationship between resistance modulation and proton diffusion was proposed by considering the effect of the electric field during hydrogenation. An electric field, in addition to thermal activation, is demonstrated to effectively control the proton distribution along its gradient with an efficiency of ∼22% at 2 × 105 V/m. The combination of an electric field and gas-phase annealing is shown to enable the elegant control of the diffusional doping of complex oxides.

Neodymium nickelate (NdNiO3: NNO), which is a typical strongly correlated metal oxide, has attracted considerable attention because of its large resistance changes due to its metal-insulator transi...

Phase-transition field-effect transistors (FETs) are a class of steep-slope devices that show abrupt on/off switching owing to the metal-insulator transition (MIT) induced in the contacting materials. An important avenue to develop phase-transition FETs is to understand the charge injection mechanism at the junction of the contacting MIT materials and semiconductor channels. Here, toward the realization of high-performance phase-transition FETs, we investigate the contact properties of heterojunctions between semiconducting transition-metal dichalcogenides (TMDCs) and vanadium dioxide (VO2) that undergoes a MIT at a critical temperature (Tc) of approximately 340 K. We fabricated transistors based on molybdenum disulfide (MoS2) and tungsten diselenide (WSe2) in contact with the VO2 source/drain electrodes. The VO2-contacted MoS2 transistor exhibited n-type transport both below and above Tc. Across the MIT, the on-current was observed to increase only by a factor of 5, in contrast to the order-of-magnitude change in the resistance of the VO2 electrodes, suggesting the existence of high contact resistance. The Arrhenius analyses of the gate-dependent drain current confirmed the formation of the interfacial barrier at the VO2/MoS2 contacts, irrespective of the phase state of VO2. The VO2-contacted WSe2 transistor showed ambipolar transport, indicating that the Fermi level lies near the mid gap of WSe2. These observations provide insights into the contact properties of phase-transition FETs based on VO2 and TMDCs and suggest the need for contact engineering for high-performance operations.

Background Human epidermal growth factor 2 (HER2) is a potential driver oncogene. Although HER2-targeted precision therapy has been tested in non-small cell lung cancer (NSCLC), the demographic characteristics of HER2-positive NSCLC have not been systematically defined. Methods Patients with pathologically confirmed stage IIIB/IV or recurrent NSCLC, Eastern Cooperative Oncology Group performance status 0 to 2, were prospectively registered. HER2 immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays were performed to screen patients. HER2 mutations were identified by using direct gene sequencing. The aim of this study was to clarify the frequency, characteristics, and outcome of HER2-positive NSCLC. HER2 was defined as positive if the tumor harbored IHC3+, IHC2+/FISH+, or exon 20 insertion mutations. Results Of the 1,126 tumors screened, 34 (3.0%) were IHC3+, and 34 (3.0%) were IHC2+/FISH+. Among the 724 epidermal growth factor receptor wild-type tumors, 21 (2.9%) were HER2-mutant tumors, including A775-G776insYVMA (n = 15). Interestingly, the IHC3+ tumors and mutant tumors were entirely exclusive. Female patients had HER2-mutant tumors more frequently, whereas both IHC3+ and IHC2+/FISH+ tumors were detected more often in male subjects and smokers. Patients with an HER2-aberrant tumor had a significantly worse prognosis than those with epidermal growth factor receptor-positive and anaplastic lymphoma kinase-positive tumors, possibly due to the low proportion that received HER2-targeted therapies (n = 15 [26%]) and low response rates of 0% and 14% in patients with HER2-overexpressing and HER2-mutant tumors, respectively. Conclusions This prospective large-scale cohort study is the first to show comprehensively the frequency and clinical demographic characteristics of those with HER2-positive advanced lung tumors in detail, providing critical historical data for future drug development against HER2-positive NSCLC. Future treatment strategies would be developed stratified according to the types of HER2 aberrations. Trial Registry UMIN Registration No. 000017003; URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000019691

Herein, we construct three-dimensional (3D) Fe3O4 epitaxial nanowires at a 10 nm length scale on a 3D MgO nanotemplate using an original nanofabrication technique that mainly comprises nanoimprint lithography and inclined thin-film deposition. Despite the high density of inevitable nanoscale defects, the ultrasmall Fe3O4 nanowires exhibit a prominent Verwey transition at about 112 K with a maximum relative change in resistance of 9.5, which is 6 times larger than that of the thin-film configuration. Numerous measurements on a large number of Fe3O4 nanowires grown concurrently on the same 3D MgO nanotemplate reveal a dramatic difference in their electrical transport property with the presence/absence of the Verwey transition. A comparative study of Fe3O4 wires of increasing volume and a thin film reveals that a profound change in the Verwey transition is observed only for wires with a volume on the order of 10 nm3. Moreover, a significant decrease in the sharpness of the resistance jump and the transition temperature of the Verwey response is noticed with an increasing volume of Fe3O4. This indicates the potency of the 3D nanofabrication technique in controlling nanoscale defects, which is further reconfirmed through magnetoresistance measurement. A feature of the magnetoresistance curve identifies the antiphase boundaries as a major source of defects. The occurrence of the smallest magnetoresistance in the ultrasmall nanowire with the highest Verwey transition temperature and resistance change ratio proves that 3D isotropic spatial confinement into a length scale comparable to the average spacing between two antiphase boundaries enables the favorable control over nanoscale defects. A simple statistical model satisfactorily illustrates the dependence of electrical transport properties on the volume of Fe3O4 from the macroscale down to the nanoscale. Finally, an ultrasmall nanowire with a low defect concentration allows the estimation of the true coherence length of the fundamental quasiparticle, the trimeron, responsible for the Verwey transition.

New fitting analyses for peak shapes in a 2D reciprocal-space map are demonstrated to evaluate the strain, strain distribution and domain size of a crystalline ultra-thin (15 Å) film of β-FeSi2(100) grown epitaxially on an Si(001) substrate, using grazing-incidence X-ray diffraction. A 2D Laue-fit analysis taking into account instrument broadening and the double-domain effect provides residual maps as a function of the inequivalent strains ɛ b and ɛ c along the b and c axes of β-FeSi2, respectively (and domain size D), reflecting the probability of existence of homogeneous domains with fixed ɛ b , ɛ c and D, in addition to the most probable minimum residual. A 2D Laue fit with an inhomogeneous domain distribution provides a population map with ɛ b and ɛ c , reflecting strain components contributing to the film. The population map also leads to a reference residual as a guide for the strains contributing to the residual map. The advantages of the 2D Laue fits are discussed by comparison with the Scherrer, Williamson–Hall and Gaussian fitting methods for equivalent systems. The analyzed results indicate that the β-FeSi2 nanofilm was considerably small strained, which was also confirmed by transmission electron microscopy, implying a weak interface interaction between the film and the substrate.

Vanadium dioxide (VO2) shows promise as a building block of switching and sensing devices because it undergoes an abrupt metal-insulator transition (MIT) near room temperature, where the electrical resistivity changes by orders of magnitude. A challenge for versatile applications of VO2 is to control the MIT by gating in the field-effect device geometry. Here, we demonstrate a gate-tunable abrupt switching device based on a VO2 microwire that is monolithically integrated with a two-dimensional (2D) tungsten diselenide (WSe2) semiconductor by van der Waals stacking. We fabricated the WSe2 transistor using the VO2 wire as the drain contact, titanium as the source contact, and hexagonal boron nitride as the gate dielectric. The WSe2 transistor was observed to show ambipolar transport, with higher conductivity in the electron branch. The electron current increases continuously with gate voltage below the critical temperature of the MIT of VO2. Near the critical temperature, the current shows an abrupt and discontinuous jump at a given gate voltage, indicating that the MIT in the contacting VO2 is thermally induced by gate-mediated self-heating. Our results have paved the way for the development of VO2-based gate-tunable devices by the van der Waals stacking of 2D semiconductors, with great potential for electronic and photonic applications.

Neodymium nickelate, NdNiO3 (NNO), with a perovskite structure shows resistance change of 1–2 orders owing to insulator–metal-transition (IMT) and metal–insulator-transition (MIT) at around 200 K and its IMT/MIT properties are affected by strain effects (Ni–O–Ni angular distribution). Since the resistance changes in the NNO system are considered to be dominated by competing nanoscale electronic phases, the reduction in sample size down to the individual domain scale could realize the direct investigation of single electric domains. In this study, 100 nm wide NNO nanowire structures were produced on NdGaO3(110) and LSAT(100) substrates, and the statistical IMT/MIT properties of electric domains under different strained structures were investigated. The nanowires showed prominent step resistance changes reflecting intrinsic first-order transition properties with different transition temperature distributions. A statistical transition model unveils the quantitative relationship between the IMT properties of the NNO nano-electronic phase and the strain effect due to the Ni–O–Ni angular distribution in NNO.

The resistance modulation under various gate voltage (Vg) application conditions was systematically studied for a chemical field effect transistor (FET) composed of a SmNiO3 (SNO) film channel and ...

The electric-field-assisted hydrogenation and corresponding resistance modulation of NdNiO

The realization of three-dimensional (3D)-architected nanostructures, that is, the transformation from novel two-dimensional (2D) film-based devices to 3D complex nanodevices, is of crucial importance with the progress of scaling down devices to nanometer order. However, little attention has been devoted to controlling the atomic ordering and structures of side-surfaces on 3D structures, while techniques for controlling and investigating 2D surfaces, namely, surface science, have been established only for planar 2D surfaces. We have established an original methodology that enables atomic orderings and arrangements of surfaces with arbitrary directions to be observed on 3D figured structures by developing diffraction and microscopy techniques. An original technique, namely, directly and quantitatively viewing the side- and facet-surfaces at the atomic scale by reflection high-energy electron diffraction (RHEED) and low-energy electron diffraction (LEED), can be used to determine process parameters in etching. This chapter introduces methods of evaluation by RHEED and LEED based on a reciprocal space map and methods of creating various atomically flat 111 and {100} side-surfaces of 3D Si nano-architectures and tilted 111 facet-surfaces fabricated by lithography dry and wet etching processes, followed by annealing treatment in vacuum.

A 67-year-old, right-handed man had a 7-year history of right-dominant, severe medication-refractory resting and action-postural tremor, rigidity, bradykinesia, and impairment of postural reflexes, with his symptoms poorly responsive to oral antiparkinsonian medication. His parkinsonian symptoms with the exception of tremor responded to levodopa infusion. His most bothersome symptom was tremor, and implantation of a left subthalamic nucleus (STN) deep brain stimulation (DBS) lead was pursued with possible posterior subthalamic area (PSA) DBS if the tremor suppression by STN was not intraoperatively sufficient. Ultimately, the STN DBS lead provided reasonable tremor suppression during the operation, and there was no need for PSA DBS. After the surgery, his tremor and other parkinsonian symptoms were well-controlled. This case highlights that unilateral STN DBS is a reasonable indication for medication-refractory parkinsonian tremor with significant laterality of bothersome symptoms, although other options may also be considered.

In Parkinson's disease (PD) patients, the factors related to weight loss remain unclear.To investigate determinants of low body mass index (BMI) in PD patients.We identified factors associated with low BMI in PD patients in a multicenter case-control study. A total of 435 PD patients and 401 controls were included.The mean BMI was significantly lower in PD patients than in controls (22.0±3.4 kg/m2 vs. 25.4±4.3 kg/m2), with an adjusted odds ratio (AOR) of 3.072 (95% CI, 2.103-4.488; p 0.001) for low BMI (22 kg/m2) in PD. Compared to the high-BMI PD group (22 kg/m2), the low-BMI PD group (22 kg/m2) had more women; a longer disease duration; higher revised Movement Disorder Society Unified PD Rating Scale (MDS-UPDRS) II and IV scores; an increased levodopa equivalent dose (LED); and increased constipation, visual hallucination, dysphagia, dyskinesia and wearing off rates. There were no between-group differences in depression, anhedonia, apathy, sleep problems and daytime sleepiness. Multivariable analysis showed that visual hallucination (AOR, 2.408; 95% CI, 1.074-5.399; p = 0.033) and the MDS-UPDRS IV (AOR, 1.155; 95% CI, 1.058-1.260; p = 0.001) contributed to low BMI after controlling for clinical factors. In a second model, visual hallucination (AOR, 2.481; 95% CI, 1.104-5.576; p = 0.028) and dyskinesia (sum of the MDS-UPDRS 4.3-4.6) (AOR, 1.319; 95% CI, 1.043-1.668; p = 0.021) significantly contributed to low BMI.PD patients were 3 times more likely than healthy controls to have a low BMI. Motor complications, particularly dyskinesia, and visual hallucination were significantly associated with low BMI in PD patients.

Solid-state ion shuttles are of broad interest in electrochemical devices, nonvolatile memory, neuromorphic computing, and biomimicry utilizing synthetic membranes. Traditional design approaches are primarily based on substitutional doping of dissimilar valent cations in a solid lattice, which has inherent limits on dopant concentration and thereby ionic conductivity. Here, we demonstrate perovskite nickelates as Li-ion shuttles with simultaneous suppression of electronic transport via Mott transition. Electrochemically lithiated SmNiO 3 (Li-SNO) contains a large amount of mobile Li + located in interstitial sites of the perovskite approaching one dopant ion per unit cell. A significant lattice expansion associated with interstitial doping allows for fast Li + conduction with reduced activation energy. We further present a generalization of this approach with results on other rare-earth perovskite nickelates as well as dopants such as Na + . The results highlight the potential of quantum materials and emergent physics in design of ion conductors.

Background Ramucirumab is a fully human monoclonal antibody (IgG1) developed for the treatment of solid tumors. To reduce the risk of an infusion-related reaction (IRR) with ramucirumab, H1-antihistamines are recommended as premedication. However, IRR is hardly observed in clinical practice in the ramucirumab regimen. The H1-antihistamines have several side effects, such as drowsiness and dizziness, and the use of H1-antihistamines might be restricted for the patients who need to drive a car or for elderly patients. The aim of this study was to investigate the safety of ramucirumab without H1-antihistamines as a premedication in patients with solid cancer. Methods We retrospectively reviewed the solid tumour patients who received ramucirumab, including regimen without H1-antihistamines at our institution between 2017 and 2019. The patients who received antiemetic steroid for cytotoxic chemotherapy was also included. The primary endpoint was the incidence of IRR during the infusion in the first cycle. The secondary endpoints were the incidence of IRR at any time and other ramucirumab related adverse events. Results Of the 51 patients enrolled (median age, 69.5 years; range 41 - 83), 28 (55%) were male. The origins of cancer were gastric cancer (n = 22), lung cancer (n = 26), and colon cancer (n = 3), respectively. Forty-two patients (82%) received ramucirumab in combination with antiemetic steroid for cytotoxic chemotherapy, and nine patients (18%) received ramucirumab monotherapy without steroid. No IRR was observed in this study (IRR rate, 0%; 95% CI 0 - 0.69). Among the overall 272 infusions, there were no events of IRRs or other ramucirumab related adverse events. Conclusions There was no IRRs without H1-antihistamines in our retrospective study. Ramucirumab without H1-antihistamines as premedication would be a favourable option for the patients who had trouble with the side effects of H1 antihistamine. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

Herein, we construct three-dimensional (3D) Fe

Vanadium dioxide (VO

The realization of atomically flat side-surfaces, which are vertical planes on a substrate, would make an enormous contribution to a paradigm shift from two-dimensional planar film structures to three-dimensional (3D) nanostructures. In this paper, we demonstrate the successful creation of well-defined Si{111}7 × 7 side-surfaces on a 3D-architected Si(110) substrate by the combination of 3D Si patterning and surface preparation techniques, as confirmed by reflection high-energy electron diffraction (RHEED). The RHEED patterns consisted of 7 × 7 diffraction spots from the Si{111} side-surfaces and 2 × 16 diffraction spots from the Si(110) top/bottom surface. We also performed the deposition of metals (Au and Ag) onto the side-surfaces, leading to the formation of Si( 1 ¯ 11 ) √3 × √3R30°-Au and Si( 1 1 ¯ 1 ¯ ) √3 × √3R30°-Ag structures. This is the first demonstration indicating super-reconstructions of such well-defined side-surfaces.

We used fluorescence microscopy to show that low adsorption of resin components by a mold surface was necessary for continuous ultraviolet (UV) nanoimprinting, as well as generation of a low release energy on detachment of a cured resin from a template mold. This is because with low mold pollution, fracture on demolding occurred at the interface between the mold and cured resin surfaces rather than at the outermost part of the cured resin. To achieve low mold pollution, we investigated the radical photopolymerization behaviors of fluorescent UV-curable resins and the mechanical properties (fracture toughness, surface hardness, and release energy) of the cured resin films for six types of di(meth)acrylate-based monomers with similar chemical structures, in which polar hydroxy and aromatic bulky bisphenol moieties and methacryloyl or acryloyl reactive groups were present or absent. As a result, we selected bisphenol A glycerolate dimethacrylate (BPAGDM), which contains hydroxy, bisphenol, and methacryloyl moieties, which give good mechanical properties, monomer bulkiness, and mild reactivity, respectively, as a suitable base monomer for UV nanoimprinting under an easily condensable alternative chlorofluorocarbon (HFC-245fa) atmosphere. The fluorescent UV-curable BPAGDM resin was used for UV nanoimprinting and lithographic reactive ion etching of a silicon surface with 32 nm line-and-space patterns without a hard metal layer.

We have studied in situ structures and magnetic properties for several iron silicides grown on Si(111)7×7 clean surfaces by the solid phase epitaxy (SPE) method: deposition of Fe at 40 K and subsequently annealing, and summarized almost all silicide phases depending on the deposition thickness and the annealing temperature as a “schematic magnetic phase diagram”. In the SPE growth, bcc-Fe(111)1×1, c-FeSi(111)1×1, 2×2, and c(4×8), α-FeSi2(112)2×2, ϵ-FeSi(111)√3 × √ 3-R30°, β-FeSi2(101)/(110) and polycrystalline phases are formed on Si(111)7×7 surfaces depending on Fe coverage (0.15–10.0 nm) and annealing temperature (470–1070 K). The structures and magnetic properties of all the above Fe silicide phases have been characterized by using in situ reflection high-energy electron diffraction, scanning tunneling microscopy, and surface magneto-optical Kerr effect. Bulk-unstable c-FeSi phases showed ferromagnetic property at 40 K and this ferromagnetism remained even after air exposure. For the c-FeSi(111)/Si(111) system, the large spin polarization was proposed at the Fe interface atoms in the B5-type interface structure between the c-FeSi(111) ultra-thin film and the Si(111) substrate by first-principle calculations.