0000000000160608

AUTHOR

Takayuki Ishikawa

Hard x-ray photoelectron spectroscopy of buried Heusler compounds

This work reports on high energy photoelectron spectroscopy from the valence band of buried Heusler thin films (Co2MnSi and Co2FeAl0.5Si0.5) excited by photons of about 6?keV energy. The measurements were performed on thin films covered by MgO and SiOx with different thicknesses from 1 to 20?nm of the insulating layer and additional AlOx or Ru protective layers. It is shown that the insulating layer does not affect the high energy spectra of the Heusler compound close to the Fermi energy. The high resolution measurements of the valence band close to the Fermi energy indicate a very large electron mean free path of the electrons through the insulating layer. The spectra of the buried thin fi…

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Probing the electronic states of high-TMR off-stoichiometric Co2MnSi thin films by hard x-ray photoelectron spectroscopy

The tunnel magnetoresistance ratio (TMR) of fully epitaxial magnetic tunnel junctions with an off-stoichiometric Co${}_{2}$MnSi Heusler alloy has been shown to exhibit a systematic dependence on Mn content, reaching 1135% at 4.2 K for Co${}_{2}$Mn${}_{1.29}$Si. In this paper, we explain the behavior of the observed TMR ratio using ab initio calculations and hard x-ray photoelectron spectroscopy (HAXPES). For the Mn-deficient samples, we show that the the drop of the TMR is caused by Co antisite atoms, which impose extra states into the minority-spin band gap. On the other hand, Mn-excess composition shows nearly half-metallic behavior. This result can be intuitively understood since both Co…

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Long-Term Outcomes and Health-Related Quality of Life (HRQoL) By Response Status for Bortezomib, Melphalan, and Prednisone (VMP) ± Daratumumab (DARA) in Alcyone

Introduction: DARA is a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action. In the phase 3 ALCYONE study (median follow-up of 40.1 months), DARA in combination with VMP (D-VMP) reduced the risk of disease progression or death by 58% versus VMP alone (median 36.4 vs 19.3 months; HR, 0.42; 95% CI, 0.34-0.51; P<0.0001) and demonstrated a significant overall survival (OS) benefit (median not reached in either group; HR, 0.60; 95% CI, 0.46-0.80; P=0.0003) for patients (pts) with transplant-ineligible newly diagnosed multiple myeloma (TIE NDMM). Here, we report the results of a subgroup analysis examining long-term efficacy outcome…

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Obinutuzumab-Based Immunochemotherapy Prolongs Progression-Free Survival and Time to Next Anti-Lymphoma Treatment in Patients with Previously Untreated Follicular Lymphoma: Four-Year Results from the Phase III GALLIUM Study

Abstract Introduction: Immunochemotherapy is standard of care treatment for previously untreated patients (pts) with advanced stage follicular lymphoma (FL). However, the majority of pts relapse, with around 20% relapsing within 2 years. Obinutuzumab (GA101; G) is a glycoengineered type II anti-CD20 monoclonal antibody (mAb) with increased antibody-dependent cell-mediated phagocytosis and cytotoxicity, and direct B-cell killing, compared with the type I mAb rituximab (R). The randomized Phase III GALLIUM study (NCT01332968) compared the efficacy and safety of G-chemotherapy (G-chemo) vs R-chemotherapy (R-chemo) in previously untreated pts with advanced stage FL. In the primary analysis (PA)…

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