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The first enantioselective synthesis of atropisomeric 9-aryltetrahydroacridines was achieved through the condensation of 2-aminoaryl ketones with alicyclic ketones. The combination of chiral phosphoric acid and an achiral primary amine promoter proved to be a competent catalytic system. Moreover, the amenability of 4-substituted cyclohexanones enabled simultaneous generation of axial and point chirality.

In this paper, we theoretically investigate how to control electron-spin polarization by δ-doping in a both magnetically and electrically confined semiconductor heterostructure. It is shown that, due to Zeeman coupling, a considerable spin polarization effect appears in the δ-doped device. It is also shown that both magnitude and sign of spin polarization can be tuned by changing weight or position of the δ-doping. Thus, a δ-doping controllable spin filter can be achieved for spintronics device applications.

High density of phenyl rings makes PAF-1 have robust structure and highly lipophilic pore, which make it very suitable for organocatalysis. However, there is no report about using PAF-1 as platform for enantioselective organocatalysis. In this paper, using PAF-1 as the platform, a chiral prolinamide catalytic site was introduced onto the framework of PAF-1 via a series of stepwise post-synthetic modifications, obtaining a novel PAF-supported chiral catalyst named PAF-1-NHPro. Then its enantioselective catalytic performance was studied by subjecting it to catalyze the model Aldol reaction between p -nitrobenzaldehyde and cyclohexanone. PAF-1-NHPro showed good diastereoselectivity and enantioselectivity with excellent and easy recyclability.

Based on a novel magnetic nanostructure with zero average magnetic field, a spin spatial splitter was recently proposed. This paper reports on how to effectively manipulate this device using a transverse electrical field with an applied bias. With the help of the stationary phase method, the lateral displacement and its spin polarization are calculated for the electron across this device. Both magnitude and sign of spin polarization are found to vary sensitively with this applied electric field. Thus, this device can be controlled conveniently by electric means, and can consequently serve as an electrically-tunable spin spatial splitter for spintronics applications.

We report a theoretical study of spin-dependent transport in a magnetic nanostructure, which can be experimentally realized by depositing a ferromagnetic metal (FM) stripe and a Schottky metal (SM) stripe on the top and at the bottom of the semiconductor heterostructure. Theoretical analysis reveals that the intrinsic symmetry in a single FM-stripe magnetic system can be broken by the SM stripe placed at the bottom of the heterostructure, and thus a sizeable spin polarization effect appears. Numerical calculation shows that not only amplitude of the spin polarization but also its sign varies with the width and/or the position of the SM stripe.

We theoretically investigate the lateral displacement of the spin electron across a hybrid magnetically modulated nanostructure. Experimentally, this nanostructure can be produced by depositing a ferromagnetic stripe with in-plane magnetization and a Schottky metal stripe on top and bottom of a semiconductor heterostructure, respectively. Theoretical analysis reveals that the inclusion of the Schottky metal stripe in single ferromagnetic-stripe nanostructure can break the intrinsic symmetry and a sizeable spin polarization in the lateral displacement will occur. Numerical calculations demonstrate that both magnitude and sign of the spin polarization can be controlled by adjusting the width and/or the position of the Schottky metal stripe in the device. Thus, based on such a hybrid magnetically modulated nanostructure, a spatial spin splitter can be proposed successfully.

We theoretically study spin-polarized transport induced by spin-orbit coupling (SOC) as well as the Zeeman interaction for electrons in a hybrid magnetic-electric-barrier semiconductor microstructure, which is constructed on surface of GaAs/AlxGa1-xAs heterostructure by patterning a ferromagnetic stripe and a Schottky-metal stripe in parallel configuration. Electron-spin polarization is found to originate mainly from spin-orbit coupling. Spin polarization can be manipulated by adjusting Rashba or Dresselhause-SOC strength, which may result into a tunable spin filter for spintronics devices.

We theoretically investigate spin transport in a novel magnetic nanostructure with zero average magnetic field, which can be experimentally realized by depositing three ferromagnetic stripes with a vertical magnetization on top and bottom of a semiconductor heterostructure. It is shown that, the electronic transmission is spin dependent, though the magnetic field is averagely vanishing, i.e., this device shows an obvious spin polarization effect. It is also shown that the degree of spin polarization depends on the incident energy and the incident direction of the electron. Therefore, such a magnetic nanostructure may be used as a spin filter for spintronics applications.

Recently, based on a novel magnetic nanostructure with zero average magnetic field, a spin spatial splitter with a considerable spin-polarized lateral displacement was proposed [Appl. Surf. Sci. 313 (2014) 545]. To further manipulate its spin-polarized behaviour, in this work, we introduce a tunable δ-potential into the device by the atomic layer doping, and calculated its effect on spin-polarized lateral displacement of the electron. Both magnitude and sign of spin polarization are found to be sensitive to the δ-doping. Therefore, such a device can serve as a structurally-controllable spin-polarized source for spintronics applications.

Based on a composite magnetic–electric-barrier nanostructure, a spin spatial splitter was proposed recently. In order to control the spin-polarized lateral displacement (LD) of electrons, a tunable δ-potential is introduced into this device by the atomic layer doping technique. Theoretical analysis together with numerical simulation shows that both magnitude and sign of spin-polarized LD change dramatically with the height and/or the position of the δ-doping. Consequently, a structurally tunable spin spatial splitter can be achieved for spintronics applications.

For an antiparallel double δ -magnetic-barrier nanostructure, there is no spin polarization due to the intrinsic symmetry. When a δ -doping is included, it is theoretically demonstrated that this device possesses a considerable spin polarization effect attributable to spin-dependent Goos–Hanchen (GH) effect of electrons. Moreover, numerical calculations show that both magnitude and sign of spin polarization in GH shifts are closely relative to height and/or location of the δ -doping, which can give rise to a controllable spin beam splitter.

We theoretically study the effect of traverse electric field on wave vector filtering (WVF) in a magnetically modulated nanostructure, which can be constructed by patterning ferromagnetic (FM) stripes on top and bottom of GaAs/Al[Formula: see text]Ga[Formula: see text]As heterostructure. Using the transfer matrix method, electric field-dependent transmission is calculated by using Weber function for electrons across the structure. We find that WVF efficiency is manipulable by adjusting direction or strength of electric field. Thus, an electrically-tunable momentum filtering device can be obtained.

Recently, a spin beam splitter, which operates via the Goos–Hanchen (GH) effect of electrons, was fabricated by depositing ferromagnetic and Schottky metal stripes on top of a semiconductor heterostructure. To explore effective manipulation of its spin polarization of GH shifts, we introduce a transverse electric field into the device. Theoretical analysis and numerical simulation show that both magnitude and sign of the spin polarization are related closely to this electric field. Thus, this spin beam splitter can be used as an electrically controllable spin-polarized source for spintronics applications.

To evaluate the efficacy, safety and survival of combination of carboplatin plus paclitaxel as neoadjuvant chemotherapy (NACT) for patients with locally advanced triple-negative breast cancer (TNBC), and explore an optimal regimen for TNBC.Patients with core needle biopsy confirmed pathological diagnosis of IIA ∼ IIIC invasive breast cancer, negative for estrogen and progesterone receptors and HER2 by immunohistochemistry, and with indication for NACT were eligible in this study. The biopsy tumor tissues were tested for CK5/6, CK14, EGFR and Ki67. The patients received paclitaxel 175 mg/m(2) on day 1, carboplatin at an area under the curve 5 mg×min/ml on day 2 of every 21 days. The clinical response was evaluated every 2 cycles according to Standard RECIST 1.0 criteria and surgery was done after four to six cycles. Pathological complete remission (pCR) was defined if absence of invasive tumor in the breast and axillary lymph nodes samples or residual carcinoma in situ only.Overall, thirty-one patients were enrolled from January 2008 to November 2010. The median age was 51 years and 83.9% of the patients were diagnosed as stage IIB to IIIC diseases. 30 Patients completed chemotherapy as planed while one patient changed regimen due to paclitaxel allergy. Twenty-eight patients could be evaluated for clinical efficacy, of which CR, PR, SD, PD were achieved in 4, 20, 3 and 1 women, respectively. The objective response rate was 85.7%. The expression rate of CK5/6, CK14 and EGFR were 88.9% (24/27), 59.3% (16/27) and 63% (17/27), respectively. Among 27 patients who received modified radical mastectomy or breast-conserving surgery, 11 patients obtained pCR, with a pCR rate of 40.7% (95%CI 22.2% - 59.3%). Five of six CK5/6- and CK14-positive patients achieved pCR. All the 31 patients could be evaluated for toxicity according to the NCI-CTC v3.0 criteria. The major toxicities were neutropenia (93.5%), vomiting (45.2%) and ALT/AST increase (32.3%), and grade 3-4 toxicities accounted for 74.2%, 3.2%, 0, respectively. Until December 2011, at a median follow-up of 28.9 months (range 5 - 47.9), eight patients developed recurrence including 5 patients died. Among 11 patients with pCR, one suffered from lung metastasis at 45 months after diagnosis and survived with tumor until now. The other ten were alive and disease free. The 3-year DFS and OS were 62% and 74.7%, respectively.As a neoadjuvant treatment for triple-negative breast cancer, carboplatin plus paclitaxel regimen achieves notable higher objective response rate and pCR rate compared with the anthracycline plus paclitaxel regimen reported in the literature, and is well tolerable. It is an optimized regimen for TNBC.