Gate-Controlled Quantum Interference Effects in a Clean Single-Wall Carbon Nanotube p-n Junction.

The precise control and deep understanding of quantum interference in carbon nanotube (CNT) devices are particularly crucial not only for exploring quantum coherent phenomena in clean one-dimensional electronic systems, but also for developing carbon-based nanoelectronics or quantum devices. Here, we construct a double split-gate structure to explore the Aharonov-Bohm (AB) interference effect in individual single-wall CNT p-n junction devices. For the first time, we achieve the AB modulation of conductance with coaxial magnetic fields as low as 3 T, where the flux through the tube is much smaller than the flux quantum. We further demonstrate direct electric-field control of the nonmonotonic magnetoconductance through a gate-tunable built-in electric field, which can be quantitatively understood in combination with the AB phase effect and Landau-Zener tunneling in a CNT p-n junction. Moreover, the nonmonotonic magnetoconductance behavior can be strongly enhanced in the presence of Fabry-Pérot resonances. Our Letter paves the way for exploring and manipulating quantum interference effects with combining magnetic and electric field controls.

Pseudomonas laoshanensis sp. nov., isolated from peanut field soil.

A novel Gram-stain-negative, aerobic strain, designated Y22T, was isolated from peanut field soil in Laoshan Mountain in China. Cells of strain Y22T were rod-shaped and motile by a single flagellum. The strain was found to be oxidase- and catalase-positive. 16S rRNA gene sequence based on phylogenetic analysis indicated that strain Y22T belonged to the genus Pseudomonas, and showed the highest 16S rRNA gene sequence similarity of 99.0% to Pseudomonas pelagia JCM 15562T, followed by Pseudomonas salina JCM 19469T (98.4%), Pseudomonas sabulinigri JCM 14963T (97.9%), Pseudomonas bauzanensis CGMCC 1.9095T (97.6%) and Pseudomonas litoralis KCTC23093T (97.5%). The phylogenetic analysis based on multilocus sequence analyses with concatenated 16S rRNA, gyrB, rpoD and rpoB genes indicated that strain Y22T belonged to Pseudomonas pertucinogena lineage. The average nucleotide identity scores between strain Y22T and closely related species were 74.6-82.8%, and the Genome-to-Genome Distance Calculator scores were 16.4-44.9%. The predominant cellular fatty acids of strain Y22T were C18:1ω7c (29.6%), C17:0 cyclo (17.5%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c) (17.4%). The genomic DNA G+C content was 57.9 mol%. On the basis of phenotypic characteristics, phylogenetic analyses and in silico DNA-DNA relatedness, a novel species, Pseudomonas laoshanensis sp. nov. is proposed. The type strain is Y22T (= JCM 32580T = KCTC 62385T = CGMCC 1.16552T).

Fiber-optic acoustic pressure sensor based on large-area nanolayer silver diaghragm.

A fiber-optic acoustic pressure sensor based on a large-area nanolayer silver diaphragm is demonstrated with a high dynamic pressure sensitivity of 160 nm/Pa at 4 kHz frequency. The sensor exhibits a noise limited detectable pressure level of 14.5 µPa/Hz(1/2). Its high dynamic pressure sensitivity and simple fabrication process make it an attractive tool for acoustic sensing and photo-acoustic spectroscopy.

Electric control of spin in monolayer WSe2 field effect transistors.

We report first-principles theoretical investigations of quantum transport in a monolayer WSe2 field effect transistor (FET). Due to strong spin-orbit interaction (SOI) and the atomic structure of the two-dimensional lattice, monolayer WSe2 has an electronic structure that exhibits Zeeman-like up-down spin texture near the K and K' points of the Brillouin zone. In a FET, the gate electric field induces an extra, externally tunable SOI that re-orients the spins into a Rashba-like texture thereby realizing electric control of the spin. The conductance of FET is modulated by the spin texture, namely by if the spin orientation of the carrier after the gated channel region, matches or miss-matches that of the FET drain electrode. The carrier current I(τ, s) in the FET is labelled by both the valley index and spin index, realizing valleytronics and spintronics in the same device.

High intrinsic ZT in InP3 monolayer at room temperature.

Two-dimensional thermoelectric (TE) materials which have the figure of merit ZT that is greater than 1.5 at room temperature would be highly desirable in energy conversion since the efficiency is competitive to conventional energy conversion techniques. Here, we report that the indium triphosphide (InP3) monolayer shows a large ZT of 1.92 at 300 K, based on the quantum calculations within the ballistic thermal transport region. A remarkably low and isotropic phononic thermal conductivity is found due to the flat lattice vibration modes, which takes a major responsibility for the impressively high ZT at room temperature. Moreover, a large ZT of 1.67 can still be achieved even under a 1% mechanical tension on the lattice. These results suggest that the InP3 monolayer is a promising candidate for low dimensional TE applications.

The role of aldehyde dehydrogenase 1A1 in B-cell non-Hodgkin's lymphoma.

Previously we showed that aldehyde dehydrogenase 1A1 (ALDH1A1) is a new mediator for resistance of DLBCL to CHOP and a facility predictor of clinical prognosis. In the present study, knockdown and inhibitor of ALDH1A1 were applied to identify the role of ALDH1A1 in Raji cells. CCK-8 and clone formation assay were applied to determine the CHOP sensitivity and clone formation ability. Caspase colorimetric assay and Annexin V/FITC staining was performed to determine the degree of apoptosis. Western blot analysis was used to detect the NF-κB/STAT3 signaling proteins and apoptotic-associated proteins. Real-time quantitative PCR (RT-PCR) was used to identify the differential expression of ALDH1A1 between NHL patients and healthy donors. We demonstrated that inhibition of ALDH1A1 increased the sensitivity of Raji cells to CHOP, as indicated by increased cytotoxicity, reduced clonogenicity, activated caspase-3/-9, decreased NF-κB/STAT3 signaling and increased pro-apoptosis signaling, ad increased apoptosis rate. Moreover, we found high ALDH1A1 expression was associated with poor prognosis in NHL patients. Our data revealed the critical role of ALDH1A1 in NHL and provides a theoretical basis for the use of ALDH1A1 inhibitors in NHL patients.

Preparation of nanoliposome loaded with peanut peptide fraction: stability and bioavailability.

Nanoliposome loaded with peanut peptide fraction (PPF) prepared by high pressure microfluidization (HPM) treatment was investigated as well as its stability and bioavailability. PPF showed hydrophilicity character with a solubility of 97.50 ± 2.31 mg mL(-1) in aqueous solution. HPM treatment can prepare nanoliposome but decreased encapsulation efficiency (EE). A pressure of 120 MPa was the appropriate parameter where the particle size and EE of nanolipsome was 79.67 ± 1.85 nm and 65.12 ± 2.96%, respectively. Crude liposome and nanoliposome both showed good stability under different pH conditions, even at pH value of 2.0. Nanoliposome behaved better in vitro controlled release than crude liposome. Most important of all, nanoliposome had the highest angiotension converting enzyme (ACE) inhibitory activity after simulated gastrointestinal tract (GIT) digestion. Morphology of digested liposome proved that nanoliposome can keep relative integrity in structure although it suffered a lot of attack.

Reversible and Nonvolatile Modulations of Magnetization Switching Characteristic and Domain Configuration in L10-FePt Films via Nonelectrically Controlled Strain Engineering.

Reversible and nonvolatile modulation of magnetization switching characteristic in ferromagnetic materials is crucial in developing spintronic devices with low power consumption. It is recently discovered that strain engineering can be an active and effective approach in tuning the magnetic/transport properties of thin films. The primary method in strain modulation is via the converse piezoelectric effect of ferroelectrics, which is usually volatile due to the reliance of the required electric field. Also the maximum amount of deformation in ferroelectrics is usually limited to be less than 1%, and the corresponding magnetoelastic strain energy introduced to ferromagnetic films is on the order of 10(4) J/m(3), not enough to overcome magnetocrystalline anisotropy energy (Ku) in many materials. Different from using conventional strain inducing substrates, this paper reports on the significantly large, reversible, and nonvolatile lattice strain in the L10-FePt films (up to 2.18%) using nonelectrically controlled shape memory alloy substrates. Introduced lattice strain can be large enough to effectively affect domain structure and magnetic reversal in FePt. A noticeable decrease of coercivity field by 80% is observed. Moreover, the coercivity field tunability using such substrates is nonvolatile at room temperature and is also reversible due to the characteristics of the shape memory effect. This finding provides an efficient avenue for developing strain assisted spintronic devices such as logic memory device, magnetoresistive random-access memory, and memristor.

Nonvolatile modulation of electronic structure and correlative magnetism of L10-FePt films using significant strain induced by shape memory substrates.

Tuning the lattice strain (εL) is a novel approach to manipulate the magnetic, electronic, and transport properties of spintronic materials. Achievable εL in thin film samples induced by traditional ferroelectric or flexible substrates is usually volatile and well below 1%. Such limits in the tuning capability cannot meet the requirements for nonvolatile applications of spintronic materials. This study answers to the challenge of introducing significant amount of elastic strain in deposited thin films so that noticeable tuning of the spintronic characteristics can be realized. Based on subtle elastic strain engineering of depositing L10-FePt films on pre-stretched NiTi(Nb) shape memory alloy substrates, steerable and nonvolatile lattice strain up to 2.18% has been achieved in the L10-FePt films by thermally controlling the shape memory effect of the substrates. Introduced strains at this level significantly modify the electronic density of state, orbital overlap, and spin-orbit coupling (SOC) strength in the FePt film, leading to nonvolatile modulation of magnetic anisotropy and magnetization reversal characteristics. This finding not only opens an efficient avenue for the nonvolatile tuning of SOC based magnetism and spintronic effects, but also helps to clarify the physical nature of pure strain effect.

[Clinical observation on influence of vertebral fixation through or across the affected vertebra on vertebral morphology].

OBJECTIVE: To compare the long-term influence of vertebral fixation through or across the affected vertebra on vertebral morphology. METHODS: Clinical data of 48 patients with simple thoracic and lumbar spinal fractures who were admitted between Jan. 2008 and Dec. 2010 were analyzed retrospectively. Among them 36 cases (28 males and 8 females) were fixed through the injured vertebra (group A) and 12 cases (8 males and 4 females) were fixed across the injured vertebra (group B). All patients were followed up for 6-36 months (mean 11.5 months). The vertebral body height, endplate angle and neurofunction were compared between the two groups before surgery, a week after surgery and at the end of the follow-up period. RESULTS: There was no statistically significant difference in vertebral body height,endplate angle and neurofunction before operation between group A and B (P > 0.05). Vertebral body height and endplate angle improved in both groups a week after operation and at the end of the follow-up period as compared with those before operation (P < 0.05), and the efficacy in group B was significantly better than that in group A (P < 0.05). There was no significant difference in neurofunction between the two groups (P > 0.05). CONCLUSION: The fixation method through the injured vertebra had a better reduction effect, more stable fixation, and a better long-term effect on vertebral morphology than that across the injured vertebra in the treatment of thoracolumbar vertebral fractures.