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The supersonic flows around a typical parachute-like two-body system are numerically studied at a freestream Mach number of 2.0. Both rigid and flexible models, composed of a capsule and a canopy, are considered. The objective is to analyze the effects of angle of attack (AoA) on the unsteady flow produced by the parachute-like two-body system and the difference in flow behaviors between the rigid and flexible systems. The following two model configurations are examined for the rigid canopy case: (1) the canopy is connected to the capsule with a rigid rod and (2) the canopy is separate from the capsule. It is found that at a moderate capsule AoA, the most unstable flow field is generated in the interior of the canopy and the connecting rod has a significant effect on the flow field. For the flexible case, the supersonic flows over the model (2) configuration and the canopy alone are investigated. An area oscillation phenomenon is observed in the flexible canopy. When the capsule AoA is increased, the flexible canopy has greater deformation, which results in a lower drag coefficient. The effect of the canopy AoA is also examined for the flexible canopy alone. A small deformation in the canopy shape is observed. [ABSTRACT FROM AUTHOR]

ERBB2 amplification is a driver oncogenic alteration in many cancers and it has recently been incorporated among therapeutically actionable biomarkers also in metastatic colorectal cancer (mCRC). In contrast, the role of ERBB2 point mutations, which are detectable in up to 3% of CRC patients, remains to be assessed. In this systematic review, we collected preclinical and clinical data addressing the role of ERBB2 point mutations in mCRC patients as a predictive biomarker for anti-EGFR and anti-HER2 targeted agents, and as mechanism of acquired resistance to ERBB2 amplified mCRC treated with any anti-HER2 regimen. In both preclinical and clinical studies, most ERBB2 point mutations were associated with resistance to anti-EGFR agents, particularly L755S and R784G, which occur in the HER2 protein kinase domain. No ERBB2 mutation was associated with tumor response to HER2-targeted agents in mCRC patients, although signals of activity were observed in preclinical models. Eight ongoing clinical trials are underway to test different anti-HER2 treatments in ERBB2 mutant mCRC. Several reports documented the emergence of ERBB2 mutations in the circulating tumor DNA (ctDNA) of ERBB2 amplified mCRC progressing to anti-HER2 agents, thus hinting a role in acquired resistance. [ABSTRACT FROM AUTHOR]

Reduction of thermal conductivity κ while preserving high electrical conductivity σ in materials continues to be a vital goal in thermoelectric study for the reuse of exhaust heat energy. In the use of an eco-friendly and ubiquitous element, Si as thermoelectric material, high κ value in bulk Si is the essential bottleneck to achieve high dimensionless figure of merit. This is a motivation for many recent studies on reducing κ in Si, by nanostructuring, e.g., using grains/wires with size smaller than the phonon mean free path. However, κ reduction that can be achieved tends to be saturated presumably due to an amorphous limit. Here, we present a nanoarchitecture for defeating the κ amorphous limit while preserving bulk-like σ . This new nanoarchitecture is an assembly of Si nanocrystals with oriented crystals separated by a 1-monolayer amorphous layer with well-controlled nanoscale shaped interfaces. At these interfaces, novel phonon scattering occurs resulting in κ reduction below the amorphous limit. Preservation of bulk-like σ results from the coherency of the carrier wavefunctions among the oriented nanocrystals separated by the ultrathin amorphous layer. The results will bring environmentally-friendly and low-cost thermoelectric Si material compatible with mature LSI process technology and represent guidelines for optimized thermoelectric nanostructures. [ABSTRACT FROM AUTHOR]

Abstract: We develop the epitaxial growth technique of ultrahigh density (>1012cm-2) iron silicide nanodots (NDs) on Si substrates using ultrathin SiO2 films. This technique enables the ND formation of various kinds of iron silicides such as β-FeSi2 and Fe3Si. These NDs nanocontact with Si substrates through limited area of nanowindows in the ultrathin SiO2 films. Due to the nanocontact between NDs and Si substrates, heteroepitaxial growth of high quality NDs on Si substrate is successful. Absorption spectra of individual β-FeSi2 NDs show the property of the indirect transition semiconductor. However, the Si/β-FeSi2 NDs/Si structures exhibit strong photoluminescence near 0.8eV. [Copyright &y& Elsevier]

Abstract: It has been found that spherical large clusters of carbon atoms are formed by irradiation of crystalline C60 films grown on Si(111)-(7×7) surfaces with electrons field-emitted from a scanning tunneling microscope probe tip. The size distribution of the clusters deduced from surface profile measurements suggests that the dominant clusters were not necessarily C60n (n =2–4) expected from the simple fusion of C60 molecules. It was proposed that electronic excitations of C60 molecules caused the fragment and coalescence of the molecules to form the giant fullerenes as in the photo-induced similar effects. [Copyright &y& Elsevier]

Abstract: Germanium quantum dots (QDs) were extracted from ultrathin Si x Ge1−x oxide films using scanning tunneling microscope (STM) tips. The extraction was most efficiently performed at a positive sample bias voltage of +5.0V. The tunneling current dependence of the extraction efficiency was explained by the electric field evaporation transfer mechanism for positive Ge ions from QDs to STM tips. Ge QDs (∼7nm) were formed and isolated spatially by extracting the surrounding Ge QDs with an ultrahigh density of >1012 cm−2. Scanning tunneling spectroscopy of the spatially-isolated QDs revealed that QDs with an ultrahigh density are electrically-isolated from the adjacent dots. [Copyright &y& Elsevier]

Injection of tunneling electrons and holes from the probe tips of a scanning tunneling microscope was found to enhance the hopping motion of Cl atoms between neighboring dangling-bond sites of Si dimers on Si(1 0 0)-(2 × 1) surfaces, featured by the rate of hopping linearly dependent on the injection current. The hopping rate formed peaks at sample biases of VS∼+1.25 and −0.85 V, which agree with the peaks in the local density of states spectrum measured by scanning tunneling spectroscopy. The Cl hopping was enhanced at Cl-adsorbed sites even remote from the injection point. The Cl hopping by hole injection was more efficiently enhanced by sweeping the tip along the Si dimer row than by tip-sweeping along the perpendicular direction. Such anisotropy, on the other hand, was insignificant in the electron injection case. All of these findings can be interpreted by the model that the holes injected primarily into a surface band originated from the dangling bonds of Si dimers propagate quite anisotropically along the surface, and become localized at Cl sites somehow to destabilize the Si–Cl bonds causing hopping of the Cl atoms. The electrons injected into a bulk band propagate in an isotropic manner and then get resonantly trapped at Si–Cl antibonding orbitals, resulting in bond destabilization and hopping of the Cl atoms. [Copyright &y& Elsevier]

Abstract: Photoabsorption properties of β-FeSi2 nanoislands epitaxially grown on Si(111) and Si(001) have been discussed using photoabsorption nano-spectroscopy based on scanning tunneling microscope. The obtained spectra exhibit clear features around 0.86–0.91eV and around 0.71–0.74eV, which are explained as a direct and an indirect photoabsorption edge of β-FeSi2, respectively. We also observed a blue shift of spectrum obtained from β-FeSi2 nanoislands on Si(111) substrates, compared to those on Si(001) substrates. We attributed the dependence on Si-substrate orientation not to a quantum confinement effect but to an effect of elastic strain in the β-FeSi2 nanoislands epitaxially grown on the substrate. [Copyright &y& Elsevier]

Background Although several studies suggested that immune checkpoint inhibitors may enhance an efficacy of radiotherapy (RT), it remains unclear in patients (pts) with advanced gastric cancer (AGC). Methods Total 34 AGC pts treated with RT for the primary gastric lesion from April 2013 to March 2019 were analyzed in this study. Pts were divided into two groups according to whether they had received nivolumab before RT or not. Primary tumor responses were assessed according to volumetry on CT scan with tumor response as > 70% decrease in tumor volume. Endoscopic responses were evaluated in pts who underwent endoscopy after RT. Tumor infiltrating lymphocytes (TILs) were also analyzed to examine the tumor microenvironmental immune status in the pts. Results Among 34 pts, 16 pts had received nivolumab before RT. There were no significant differences in baseline characteristics between nivolumab-exposed and nivolumab-naive groups. 70% tumor reductions by RT were observed in 25% (4/16) in nivolumab-exposed group but no patients (0/18) in nivolumab-naive group (P = 0.039). Among pts who received endoscopy after RT, four of seven pts in nivolumab-exposed group experienced partial response, while no response was observed among 10 nivolumab-naive pts (P = 0.015). TILs were evaluated in pts whose tumor samples were available. CD8+ T cells/effector regulatory T cells (eTreg cells) ratio in TILs was markedly increased after nivolumab in pts who achieved response, but not observed in pts who had no tumor reduction. A significant increase of CD8+ T cells/eTreg cells ratio after nivolumab treatment was observed in nivolumab-exposed pts (n = 15), whereas such a tendency was not observed in nivolumab-naive pts (n = 10). Conclusions RT to primary gastric cancer significantly led to tumor response in nivolumab-exposed pts compared with nivolumab-naive pts. Immune profiling suggested that nivolumab might enhance the sensitivity to RT by immunoactivation via increasing CD8+ T cell/eTreg cell ratio. [ABSTRACT FROM AUTHOR]

Background: Pembrolizumab, an anti-PD-1 antibody, results in tumour response in around 15% of patients with advanced gastric cancer who have a PD-L1 combined positive score of at least 1. Lenvatinib, a multikinase inhibitor of VEGF receptors and other receptor tyrosine kinases, substantially decreased tumour-associated macrophages and increased infiltration of CD8 T cells, resulting in enhanced anti-tumour activity of PD-1 inhibitors in an in-vivo model. We aimed to assess the combination of lenvatinib plus pembrolizumab in patients with advanced gastric cancer in a phase 2 study.Methods: This study was an open-label, single-arm, phase 2 trial undertaken at the National Cancer Center Hospital East (Chiba, Japan). Eligible patients were aged 20 years or older and had metastatic or recurrent adenocarcinoma of the stomach or gastro-oesophageal junction, an Eastern Cooperative Oncology Group performance status of 0 or 1, and measurable disease according to the Response Evaluation Criteria in Solid Tumors (RECIST version 1.1), irrespective of the number of previous lines of treatment. Patients received 20 mg oral lenvatinib daily plus 200 mg intravenous pembrolizumab every 3 weeks until disease progression, development of intolerable toxicity, or withdrawal of consent. The primary endpoint was objective response rate according to RECIST, analysed in all patients who were eligible and received protocol treatment at least once. The safety analysis included all those who received protocol treatment at least once, regardless of eligibility. This study is registered at ClinicalTrials.gov, NCT03609359, and enrolment is complete.Findings: Between Oct 15, 2018, and March 25, 2019, 29 patients were enrolled in the first-line or second-line settings. At data cutoff (March 20, 2020), the median follow-up was 12·6 months (IQR 10·5-14·3). 20 (69%, 95% CI 49-85) of 29 patients had an objective response. The most common grade 3 treatment-related adverse events were hypertension (in 11 [38%] patients), proteinuria (five [17%]), and platelet count decrease (two [7%]). No grade 4 treatment-related adverse events, serious treatment-related adverse events, or treatment-related deaths occurred.Interpretation: Lenvatinib plus pembrolizumab showed promising anti-tumour activity with an acceptable safety profile in patients with advanced gastric cancer. On the basis of these results, a confirmatory trial will be planned in the future.Funding: Merck Sharp & Dohme. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the electronic structures of URu2Si2 employing ultrahigh-resolution laser angle-resolved photoemission spectroscopy. The change of photoemission spectra is investigated across the hidden-order transition, and the emergence of a narrow band is clearly observed near the Fermi level for both and directions. In addition, it is shown that tuning of light''s polarization allows the signal of a hole-like dispersive feature to enhance. These observations prove that laser angle-resolved photoemission spectroscopy is an effective tool for studying the evolution of electronic structures across the hidden-order transition in URu2Si2. [Copyright &y& Elsevier]

Abstract: A 68-year-old female, suffering from rheumatoid arthritis, was admitted to our institution for right heart failure with massive pericardial effusion. Her pericardial effusion had increased after starting infliximab, tumor necrosis factor (TNF)-inhibitor therapy, despite improvement in arthralgia. Hemodynamic findings demonstrated effusive–constrictive pericarditis. Because association between exacerbation of pericarditis and infliximab was highly suspected through her clinical course, its administration was stopped. We should pay much attention to pericardial effusion and symptoms of right heart failure after starting TNF-inhibitor therapy in patients with rheumatoid arthritis. [Copyright &y& Elsevier]