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We report on the magnetotransport properties of 100 nm wide parabolic quantum wells and observe an enhancement of the Hall resistance in one sample but not the other. This phenomenon is likely related to the effective thickness of the electronic slab. We also observe a parabolic negative magnetoresistance originating from electron-electron interactions when only one subband is occupied in one of the samples. The interaction correction to the Drude conductivity is extracted using two methods. We find that the extracted interaction correction increases with increasing tilted angle, for which two possible explanations are given. [ABSTRACT FROM AUTHOR]

The weak antilocalization (WAL) effects of the two-dimensional electron gas (2DEG) in high mobility AlxGa1-xN/GaN heterostructure as well as beating patterns in the Shubnikov–de Haas (SdH) oscillatory magnetoresistance have been investigated by means of magnetotransport measurements before and after illumination. The zero-field spin splitting mainly arising from the Rashba spin-orbit coupling effect is studied using the weak antilocalization and beating patterns analysis, respectively. The Rashba spin-orbit coupling constant α deduced using the weak antilocalization analysis showed a good agreement with that estimated from the analysis of the beating patterns for the sample before and after illumination. For our sample, the electron motion in the high mobility system is in the ballistic regime, the experimental WAL curves were fitted by a simulated quantum conductance correction according to a model proposed by [Golub [Phys. Rev. B 71, 235310 (2005)]. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the expressions, biological effects and potential mechanism of miR-424 in glioma. METHODS AND METHODS: A total of 54 glioma tissues and 12 normal brain tissues were collected. Human glioma cells (A172, SHG-44, T98, LN18, and LN229) and normal human astrocytes (NHAs) were cultured. Cell invasion and migration capacities were detected by transwell assay. KIF23 was predicted and confirmed as a direct target of miR-424 by TargetScan prediction and Dual-luciferase reporter assay. Six-week-old female nude mice were used for Xenograft tumor formation assay. RESULTS: Results of this study demonstrated a significant decrease of miR-424 expressions both in glioma cells and tissues. Moreover, the declined miR-424 expressions were observed to be correlated with the poor OS and worse clinicopathological parameters of glioma patients. Functional assays indicated that miR-424 restoration could inhibit the glioma cell epithelial-to-mesenchymal transition (EMT) and metastasis, as well as the tumor growth rate and tumor size of glioma mice. Additionally, kinesin family member 23 (KIF23) expressions were found to be significantly enhanced in glioma specimens, and KIF23 was considered to be a functional target for miR-424 in glioma. CONCLUSIONS: MiR-424, considered as a tumor-suppressor, inhibited cell metastasis and EMT by targeting KIF23 in glioma, which may provide a novel insight into tumorigenesis and the basis for the development of miRNA-targeting therapies against glioma. [ABSTRACT FROM AUTHOR]

Based on the method of the vectorial angular spectrum of a laser beam, an analytical expression of the electric field of an elegant Laguerre-Gaussian laser beam in source region is derived without any approximation, and the corresponding magnetic field is obtained by taking the curl of the electric field. By using the obtained expressions of the electromagnetic fields, the orbital angular momentum density of the elegant Laguerre-Gaussian laser beam can be accurately calculated. The effects of the angular mode number, the radial mode number and the linearly polarized angle as well as the beam waist width on the distribution of the orbital angular momentum density of the elegant Laguerre-Gaussian laser beam are investigated, respectively. Also, the orbital angular momentum density distribution of the propagating part of the elegant Laguerre-Gaussian laser beam is compared with that of the whole laser beam. Upon propagation, the orbital angular momentum density difference between the propagating part and the whole laser beam decreases. This research is beneficial to the optical manipulation with an elegant Laguerre-Gaussian laser beam. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The long non-coding RNA BCAR4 (BCAR4) has been reported to be associated with cancer development. The aim of our study was to investigate the expression of BCAR4 in osteosarcoma patients and its association with clinicopathologic parameters and the prognosis. PATIENTS AND METHODS: Quantitative RTPCR (qRT-PCR) assay was used to detect the expression of BCAR4 and its correlations with clinicopathological factors were statistically analyzed. The clinical and prognostic significance of BCAR4 expression was analyzed statistically by Kaplan- Meier estimate and Cox regression model. Furthermore, Cell proliferation, migration, and invasion were evaluated using counting assay Kit-8 (CCK-8) and transwell assay, respectively. RESULTS: We found that BCAR4 expression was higher in osteosarcoma tissues and cell lines than that in normal controls. The BCAR4 levels were significantly correlated with clinical stage and distant metastasis. Kaplan-Meier analysis with the log-rank test indicated that high expression of BCAR4 had a decreased overall survival (OS). Univariate and multivariate analyses showed that BCAR4 expression was an independent predictor of overall survival. Furthermore, decreased expression of BCAR4 markedly inhibited osteosarcoma cell proliferation, migration, and invasion. CONCLUSIONS: The results of the present study identified a crucial tumor promotive role of BCAR4 in the progression of osteosarcoma, and suggested that BCAR4 may be a potential therapeutic agent for the treatment of osteosarcoma. [ABSTRACT FROM AUTHOR]

This study investigated Zn-bearing zeolite clinoptilolite (Zn-ZCP) as a Zn supplement on performance, organ or tissue development, Zn accumulation in tissues, and gene expression of Zn transporters in the duodenum of broilers. A total of 300 1-d-old Arbor Acres chickens were randomly allocated to 5 dietary treatments with 6 replicate cages of 10 birds per treatment for a 21-d feeding period. The treatments comprised a basal corn-soybean meal diet without supplemental Zn (the control) or similar diets supplemented with 80 mg/kg Zn from ZnSO4 or 20, 40, or 80 mg/kg Zn from Zn-ZCP, respectively. Supplementation of Zn-ZCP had a positive effect on G:F (linear, P < 0.05) and had tendency difference on ADG (linear, P < 0.1) of broilers during 1 to 21 d. Incremental Zn-ZCP inclusion in the diet increased the fresh weight of the pancreas (linear, P < 0.05) and tibia (linear, P < 0.05) in broilers on d 14. The same trend to the fresh weight of the tibia (linear, P < 0.05) and pancreas (linear, P < 0.05) was observed on d 21. Increasing Zn-ZCP level showed a linear response on Zn concentration in the liver (linear, P < 0.001), pancreas (linear, P < 0.05), and tibia (linear, P < 0.05) on d 14. The same trend of Zn concentrations in pancreas (linear, P < 0.05) and tibia (linear, P < 0.001) was observed on d 21. The mRNA levels of Zn transporter 2 (ZnT-2) and Zn transporter 5 (ZnT-5) in the duodenum of chicks fed the diet with 80 mg/kg Zn from Zn-ZCP did not differ from those of chicks fed the control diet, but both were lower (P < 0.05) than those of chicks fed ZnSO4 diet. Metallothionein (MT) mRNA levels of broilers fed the diet supplemented with 80 mg/kg Zn from Zn-ZCP or ZnSO4 was higher (P < 0.05) than that in the control group. Dietary treatments did not affect the mRNA expression of Zn transporter 1 (ZnT-1) or metal response element-binding transcription factor-1 (MTF-1). In conclusion, as a Zn supplement, Zn-ZCP was comparable to ZnSO4 for enhancing Zn accumulation and growth performance of broilers during 1 to 21 d. Broilers fed the diet with 80 mg/kg Zn from Zn-ZCP had different expressions of ZnT-2 and ZnT-5 in the duodenum compared with those fed the ZnSO4 diet. [ABSTRACT FROM AUTHOR]