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A new method is proposed for robust partial quadratic eigenvalue assignment problem (RPQEAP) with repeated prescribed eigenvalues. We first derive a result on the solution of partial quadratic eigenvalue assignment problem, which leads to the partial Schur form of the close-loop system. Then by minimizing the normality departure of the partial Schur form of the close-loop system, we assign the prescribed eigenvalues step by step such that the close-loop system is as robust as possible. Our method allows the prescribed eigenvalues are repeated. Moreover, the proposed method does not use the unchanged eigenpairs of the open-loop system and avoids transforming the second-order control system to the first-order system. Numerical experiments show that the proposed method is efficient for solving the RPQEAP with repeated eigenvalues.

Steroidal anti-inflammatory drugs have certain side effects in the treatment of hypertrophic scar, and the scar recurrence is easy after withdrawal of steroid anti-inflammatory drugs. Finding reliable alternative drugs is an effective means to improve this defect. Aspirin, a traditional non-steroidal anti-inflammatory drug, is safe for topical use and has anti-inflammatory effects similar to those of steroidal anti-inflammatory drugs, which may have similar effects on the treatment of hypertrophic scar. This study aims to investigate the inhibitory effect of aspirin on the proliferation of hypertrophic scar in rabbit ears and the underlying mechanism.The rabbit ear hypertrophic scar models were prepared. The rabbits were randomly divided into a normal skin group (group A), a blank control group (group B), a 0.9% NaCl group (group C), a 0.2% aspirin group (group D), a 0.5% aspirin group (group E), a 2% aspirin group (group F), and a triamcinolone acetonide group (group G). Macroscopic observation of hyperplasia was performed 8 weeks after local injection of the scar, followed by collecting the scar tissue samples for HE staining, Masson staining, and immunohistochemistry, respectively to assess the proliferation of fibroblasts and collagen fibers, and calculate the hypertrophic index, microvessel density, and immunohistochemical score.All rabbit ear hypertrophic scar models were successfully constructed. In groups B and C, the hypertrophic scar edge was irregular, with reddish protruding epidermis, significant contracture and hard touch. In group D, E, and F, with the increase of aspirin administration concentration, the scar became thinner and gradually flat, the proliferation of fibrocytes and collagen fibers was weakened, and the hypertrophic index was gradually decreased (Local injection of aspirin can reduce the generation of hypertrophic scar in a dose-dependent manner within a certain concentration range; aspirin inhibits the growth of hypertrophic scar in rabbit ears by inhibiting Wnt/β-catenin signal pathway; 2% aspirin and 40 mg/mL triamcinolone acetonide have similar curative efficacy on hypertrophic scar.

We consider the problem of extracting a few desired eigenpairs of the buckling eigenvalue problem $Kx = \lambda K_Gx$, where $K$ is symmetric positive semi-definite, $K_G$ is symmetric indefinite, and the pencil $K - \lambda K_G$ is singular, namely, $K$ and $K_G$ share a non-trivial common nullspace. Moreover, in practical buckling analysis of structures, bases for the nullspace of $K$ and the common nullspace of $K$ and $K_G$ are available. There are two open issues for developing an industrial strength shift-invert Lanczos method: (1) the shift-invert operator $(K - \sigma K_G)^{-1}$ does not exist or is extremely ill-conditioned, and (2) the use of the semi-inner product induced by $K$ drives the Lanczos vectors rapidly towards the nullspace of $K$, which leads to a rapid growth of the Lanczos vectors in norms and cause permanent loss of information and the failure of the method. In this paper, we address these two issues by proposing a generalized buckling spectral transformation of the singular pencil $K - \lambda K_G$ and a regularization of the inner product via a low-rank updating of the semi-positive definiteness of $K$. The efficacy of our approach is demonstrated by numerical examples, including one from industrial buckling analysis.

The immediate and delayed metabolic changes in rats treated with valproate (VPA), a drug used for the treatment of epilepsy, were profiled. An established approach using dried blood spots (DBS) as sample matrices for gas chromatography/mass spectrometry-based metabolomics profiling was modified using double solvents in the extraction of analytes. With the modified method, some of the previously undetectable metabolites were recovered and subtle differences in the metabolic changes upon exposure to a single dose of VPA between males and female rats were identified. In male rats, changes in 2-hydroxybutyric acid, pipecolic acid, tetratriacontane and stearic acid were found between the control and treatment groups at various time points from 2.5 h up to 24 h. In contrast, such differences were not observed in female rats, which could be caused by the vast inter-individual variations in metabolite levels within the female group. Based on the measured DBS drug concentrations, clearance and apparent volume of distribution of VPA were estimated and the values were found to be comparable to those estimated previously from full blood drug concentrations. The current study indicated that DBS is a powerful tool to monitor drug levels and metabolic changes in response to drug treatment.

Eigenvector derivatives of eigenproblems analytically dependent on parameters are required in diverse technical fields such as structural design, system identification. Modal methods, a kind of popular methods in engineering problems, calculate eigenvector derivatives by expressing them as linear combinations of eigenvectors of eigenproblems. In this paper, an incomplete modal method is presented to compute eigenvector derivatives of polynomial eigenproblems analytically dependent on parameters. The proposed method only uses a small part of eigenvectors of polynomial eigenproblems. The contributions of other eigenvectors to eigenvector derivatives are approximated by an iterative formula. Our method can simultaneously compute the eigenvector derivatives corresponding to several eigenvalues, and it is effective whether the differentiated eigenvectors correspond to simple or semisimple eigenvalues, and whether the leading coefficient matrix is singular or not. Numerical examples are given to test the efficiency of the proposed method.

Summary BiVO4 is a promising photoanode material for solar-assisted water splitting in a photoelectrochemical cell but has a propensity to degrade. Investigations carried out here in 0.1 M Na2SO4 electrolyte showed that degradation is by dissolution of V in the electrolyte while Bi is retained on the anode probably in the form of solid Bi oxide (Bi2O3, Bi4O7). Accumulation of Bi oxide on the anode surface leads to passivation from further degradation. Thermodynamic modeling of possible degradation reactions has provided theoretical support to this mechanism. This self-passivation is accompanied by a decrease in photocurrent density, but it protects the anode against extensive photocorrosion and contributes to long-term stability. This is a more definitive understanding of degradation of BiVO4 during water splitting in a photoelectrochemical cell. This understanding is imperative for both fundamental and applied research., Graphical Abstract, Highlights • A mechanism of degradation is developed for BiVO4 photoanode during photolysis • Degradation occurs by V dissolution and Bi accumulation on the anode as oxide • Accumulating Bi oxide passivates the anode • Thermodynamic modeling supports this mechanism, Electrochemical Energy Storage; Electrochemical Energy Conversion; Chemical Reactions in Materials Science; Materials Characterization

Background: IMD-0354 is a kind of hydrophobic small molecule inhibitor of IKKβ, which can effectively inhibit the NF-κB pathway. Besides, IMD-0354 can inhibit a variety of tumor cells in culture, but its poor water solubility and low utilization have limited its clinical application. Methods: In this study, IMD-0354 was synthesized through esterifying the folate acid (FA) conjugated dextran (Dex) as well as the lauryl alcohol (LA). Results:The particle (IMD/FA-Dex-LA) size was 212.13±10.62nm, the encapsulation efficiency was 89.27±6.51%, and the drug loading was 4.25±0.42%. Cell viability studies indicated that the IMD/FA-Dex-LA effectively inhibited survival of B16F10 cells in culture. Meanwhile, Western Blotting results showed that the nuclear transport of NF-κB was reduced after blocking the IKK pathway, which would thereby suppress melanoma cell division and proliferation. Moreover, subcutaneous tumor implantation experiment revealed that, the drug-loading complex had an obvious effect on suppressing melanoma cells. Findings of this study demonstrated that the IMD-0354 loaded FA-Dex-LA was more effective than IMD-0354 alone. Conclusion: In summary, FA-Dex-LA has been successfully synthesized in this study, which can serve as a carrier for hydrophobic drug. Further, it is believed the FA-Dex-LA can potentially applied in cancer treatment.

A new receptance method is proposed for partial quadratic pole assignment problem (PQPAP) of asymmetric systems with multi-input. We use receptance matrices of symmetric parts of open-loop systems to express the solution of PQPAP. Then we derive the sensitivities of changed eigenvalues of close-loop system and give the measure of robustness. On these grounds, an algorithm for solving the robust and minimum norm PQPAP is put forward. Our method utilizes receptance matrices of symmetric parts of asymmetric systems and it is applicable to the systems with multi-input. Finally, numerical results are given to show the efficiency of our method.

Can Liu,1 Huiqing Xie,2 Jingang Yu,3 Xiaoqing Chen,3 Shijie Tang,4 Lichun Sun,5 Xiang Chen,6 Defei Peng,7,* Xiangyan Zhang,8,* Jianda Zhou1,* 1Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China; 2Department of Rehabilitation, The Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China; 3School of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, 410013, China; 4Cleft Lip and Palate Treatment Center, The Second Affliated Hospital, Shantou University Medical College, Shantou, Guangdong, 515041,China; 5Department of Medicine, School of Medicine, Tulane Health Sciences Center, New Orleans, LA, USA; 6Department of Dermatology, The Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China; 7Department of Burns and Plastic Surgery, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, 550002, China; 8Department of Nursing, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China *These authors contributed equally to this work Background: Nowadays, the combination of microRNA (miR) is attracting increased attention in clinical cancer trials. However, the clinical use of miR is highly limited because of certain properties such as instability, low-specificity distribution, and metabolic toxicity. Methods: In order to improve the anti-tumor efficacy and reduce the side effects of miR in treating melanoma, a combination of graphene oxide (GO), chitosan (CS), and a cellular penetrating peptide, MPG, was prepared with solid dispersion method in this research. The research has analyzed the specific components of nano drug-loading complexes GO-CS and GO-CS-MPG through characterization research and confirmed the bio-safety of the carrier material GO-CS-MPG. Results: The GO-CS-MPG-miR33a/miR199a nano drug-loading complex was successfully constructed and its medical effectiveness was verified. Through the subcutaneous tumor implantation experiment, an evident effect of the drug-loading complex in inhibiting melanoma cells was proven. Conclusion: Results suggest that GO-CS-MPG may have potential applications in melanoma therapy. Keywords: melanoma, graphene oxide, chitosan, cellular penetrating peptide, microRNA

This paper considers the partial quadratic eigenvalue assignment problem (PQEAP) in active vibration control using state feedback. A receptance method is proposed for PQEAP such that the norms of feedback matrices and the condition number of close-loop system are simultaneously minimized. The real form of the proposed method is developed. The proposed method only uses receptance matrices and the unwanted eigenpairs of open-loop system. The system matrices and the unchanged eigenpairs of open-loop system are not required. The efficiency of the proposed method is illustrated by some numerical examples.

OBJECTIVE To assess the viability and biomechanics of bare diced cartilage grafts. METHODS Cartilage samples were collected from 1 ear in 15 rabbits as well as costal cartilage. Each rabbit was inserted bare diced- and single-strip costal-cartilage grafts, respectively, into paraspinal subcutaneous pockets: after euthanasia at 2 months, specimens were weighed, with diced cartilage grafts examined histomorphologically by hematoxylin-eosin staining, masson trichrome staining, and immunohistochemistry. Finally, biomechanical properties of grafts were assessed. RESULTS Bare diced cartilage grafts were connected into an integrated mass after 2 months, and inward growth of fibrous tissues and angiogenesis were observed. Mean wet weights of diced cartilage grafts were 1.603 ± 0.278 and 1.662 ± 0.204 g pre- and postoperation, respectively; those of costal cartilage grafts were 0.053 ± 0.008 and 0.058 ± 0.008 g, respectively. In compression assays, mean modulus values of elasticity at yield in diced- and costal-cartilage grafts were 7.65 ± 0.59 and 22.30 ± 1.15 MPa, respectively (P

A new method is proposed to compute the eigenvector derivative of a quadratic eigenvalue problem (QEP) analytically dependent on a parameter. It avoids the linearization of the QEP. The proposed method can be seen as an improved incomplete modal method. Only a few eigenvectors of the QEP are required. The contributions of other eigenvectors to the desired eigenvector derivative are obtained by an iterative scheme. From this point of view, our method also can be seen as an iterative method. The convergence properties of the proposed method are analyzed. The techniques to accelerate the proposed method are provided. A strategy is developed for simultaneously computing several eigenvector derivatives by the proposed method. Finally some numerical examples are given to demonstrate the efficiency of our method.

Vacuum sealing drainage (VSD) is an effective technique used to promote wound healing. However, recent studies have shown that it exerts positive pressure (PP) rather than negative pressure (NP) on skin. In this study, we created a homemade device that could maintain NP on the wound, and compared the therapeutic effects of VSD-induced PP to those of our home-made device which induced NP on wound healing. The NP induced by our device required less time for wound healing and decreased the wound area more efficiently than the PP induced by VSD. NP and PP both promoted the inflammatory response by upregulating neutrophil infiltration and interleukin (IL)-1β expression, and downregulating IL-10 expression. Higher levels of epidermal growth factor (EGF), transforming growth factor (TGF)-β and platelet-derived growth factor (PDGF), and lower levels of basic fibroblast growth factor (bFGF) were observed in the wound tissue treated with NP compared to the wound tissue exposed to PP. Proliferation in the wound tissue exposed to NP on day 10 was significantly higher than that in wound tissue exposed to PP. NP generated more fibroblasts, keratinized stratified epithelium, and less epithelia with stemness than PP. The levels of ccollagen I and III were both decreased in both the NP and PP groups. NP induced a statistically significant increase in the expression of fibronectin (FN) on days 3 and 10 compared to PP. Furthermore, the level of matrix metalloproteinase (MMP)-13 increased in the NP group, but decreased in the PP group on day 3. NP also induced a decrease in the levels of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 during the early stages of wound healing, which was significantly different from the increasing effect of PP on TIMP-1 and TIMP-2 levels at the corresponding time points. On the whole, our data indicate that our homemade device which induced NP, was more efficient than VSD-induced PP on wound healing by regulating inflammation, secretion, proliferation and the distribution of different cells in wound tissue.

Adipose-derived stem cells (ADSCs) have emerged as a cell source for regeneration medicine. ADSCs possess the capacity to differentiate into endothelial cells and serve an essential role in vascular development and function. LncRNA taurine upregulated gene 1 (TUG1) has recently been linked with angiogenesis in hepatoblastoma. However, the roles of TUG1 in endothelial differentiation of ADSCs remain unidentified. Human adipose-derived stem cells (hADSCs) were obtained and characterized by flow cytometry, Oil red O and Alizarin Red staining. HADSCs were maintained in the endothelial differentiation medium and the expressions of TUG1, miR-143, and FGF1 were examined by qRT-PCR. To assess endothelial differentiation, the expressions of CD31, von Willebrand factor (vWF), VE-cadherin were examined by Western blot analysis, qRT-PCR, and immunofluorescence. Tube formation in Matrigel was examined. The interactions between TUG1 and miR-143, miR-143 and FGF1 were validated by luciferase assays. During the endothelial differentiation process, TUG1 and FGF1 were upregulated, whereas miR-143 was downregulated. TUG1 overexpression downregulated miR-143, upregulated FGF1, CD31, vWF, and VE-cadherin, and enhanced capillary tube formation. Luciferase assays showed that TUG1 interacted with miR-143, and FGF1 was a direct target of miR-143. Furthermore, the enhancement of endothelial differentiation induced by TUG1 overexpression was abolished by miR-143 overexpression. Our findings implicated that lncRNA TUG1 promoted endothelial differentiation of ADSCs by regulating the miR-143/FGF1 axis.

BiVO4 is a promising photoanode material for solar assisted water splitting in a photoelectrochemical cell but has a propensity to degrade. Investigations carried out here in 0.1 M Na2SO4 electrolyte showed that degradation is by dissolution of V in the electrolyte while Bi is retained on the anode probably in the form of solid bismuth oxide (Bi2O3, Bi4O7). Accumulation of Bi oxide on the anode surface leads to passivation of the photoanode from further degradation. Thermodynamic modelling of possible degradation reactions has provided theoretical support to this mechanism. This self-passivation is accompanied by a decrease in photocurrent density but, it protects the anode against extensive photocorrosion and contributes to long-term stability. This disclosure is a more definitive understanding of degradation of BiVO4 during water splitting in a photoelectrochemical cell. This understanding is imperative for both fundamental and applied research.

// Biao Xie 1, 2, * , Ke Cao 3, * , Jinjin Li 3 , Jia Chen 1 , Jintian Tang 4 , Xiang Chen 5 , Kun Xia 6 , Xiao Zhou 7 , Yan Cheng 8 , Jianda Zhou 1 , Huiqing Xie 9 1 Deptment of Plastic Surgery, Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, China 2 Department of Colorectal Surgery, Second Affiliated Hospital, Hunan University of Chinese Medicine, Changsha, Hunan 410005, China 3 Department of Oncology, Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, China 4 Institute of Medical Physics and Engineering, Department of Engineering Physics, Tsinghua University, Beijing, 100084, China 5 Department of Dermatology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China 6 State Key Laboratory, Medical Genetic, Central South University, Changsha, Hunan 410008, China 7 Department of Oncoplast & Reconstructure Surgery, Affiliated Tumor Hospital, Central South University, Changsha, Hunan 410013, China 8 School of Pharmacy, Central South University, Changsha, Hunan 410013, China 9 Department of Rehabilitation, Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, China * These authors have contributed equally to this work Correspondence to: Jianda Zhou, email: doctorzhoujianda@163.com Huiqing Xie, email: 975979752@qq.com Keywords: Hmgb1, NF-κB, melanoma, Klotho, insulin signaling Received: March 01, 2016 Accepted: September 26, 2016 Published: October 13, 2016 ABSTRACT The molecular and cellular mechanisms behind the involvement of inflammation in melanoma have not been fully elucidated. In this study, knockdown of Hmgb1 expression increased apoptosis, reduced invasion and p-NF-κB expression, but increased Klotho protein level in melanoma tumor cells. The effect of Hmgb1 knockdown was overcome by LPS. Introduction of exogenous Hmgb1 significantly decreased apoptosis, increased invasion, elevated p-NF-κB, but lowered Klotho protein level in melanoma cells. The effect of exogenous Hmgb1 was agonized by NF-κB inhibitor CAPE. Hmgb1 knockdown activated, but exogenous Hmgb1 inactivated, p-IGF1R/p-PI3K p-85/p-Akt/p-mTOR signaling. Knockdown of Klotho gene expression significantly decreased apoptosis, increased invasion in melanoma cells, and inhibited xenograft A375 tumor growth. A significantly high percentage of cells stained positive for p-NF-κB, but negative for Klotho, in melanoma tissues compared to normal and benign skin tissues. The positive p-NF-κB and negative Klotho protein expression correlated with poor prognosis in melanoma patients. Multivariate analysis revealed an independent association between p-NF-κB / Klotho protein level and overall survival. In conclusion, Hmgb1 can inhibit Klotho gene expression and malignant phenotype in melanoma cells through activation of NF-κB signaling.

A novel hard disk lubricant IDL2 was synthesised by reacting sodium 4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)phenoate with hexachlorocyclotriphosphazene, followed by treatment with 1H,1H-perfluoro-3,6,9-trioxatridecan-1-ol in the presence of sodium hydride and subsequent hydrolysis using sulfuric acid. The chemical structure of IDL2 was confirmed by proton nuclear magnetic resonance (1H NMR), phosphorus-31 (31P) NMR spectroscopy and mass spectrometer. The thermal property of IDL2 was analysed using thermal gravimetric analysis (TGA) and it shows better thermal stability than two commercial lubricants Z-DOL and Z-Tetraol with two and four terminal hydroxy groups, respectively. IDL2 was found to have comparable hydrophobicity to commercial lubricants Z-DOL, A20H and Z-Tetraol with water contact angles in the range of 78 – 85°, revealing that IDL2 has analogous surface energy to these commercial lubricants. IDL2 exhibits comparable friction coefficient to A20H and Z-Tetraol, but much lower than Z-DOL. More interestingly, it has a much high bonding ratio when compared with commonly used commercial lubricants under the same testing conditions due to the presence of two polar hydroxy groups, which enhance the interaction between lubricant and substrate. These promising properties of IDL2 show that it would be very potential for real application as a hard disk drive lubricant. Copyright © 2016 John Wiley & Sons, Ltd.

In this paper, a new iterative method is proposed to calculate a few eigenpair derivatives of damped systems. The proposed method simultaneously computes the derivatives of several simple eigenvalues and their corresponding eigenvectors. Eigenpair derivatives are directly determined in n-space. Moreover, our method does not require the left eigenvectors. Convergence theory of the proposed method is given. On these grounds, using vector ϵ -algorithm, acceleration techniques for our method are provided and analyzed. Finally some numerical experiments are reported to show the efficiency of the proposed methods.

Novel cyclotriphosphazene based lubricant oil ( Lube-PN ) for heat-assisted magnetic recording media was synthesized by reacting hexachlorocyclotriphosphazene with pentafluorophenol, followed by treatment with a hydroxy-terminated perfluoropolyether in a high yield. Its chemical structure was confirmed by 1 H and 31 P NMR. Its properties including viscosity, thermal stability, tribology, laser resistance as well as mobility behaviour on the hard disk surface were investigated. The thermal properties of Lube-PN were analysed using thermogravimetric analysis, and the thermal aging results showed that the about 80% of Lube-PN was retained even after heating at 300 °C for 8 h. The Lube-PN also exhibited comparable bonding ratio, friction coefficient, moderate mobility and better laser resistance than commercial perfluoropolyether based lubricant oils.

Melanoma is a highly malignant tumor. Prognoses of melanoma patients are often unsatisfactory due to poor operational and chemoradiational efficacy. Recently, researches for melanoma treatment have found multipeptide vaccines a favorite and possible breakthrough as they are stable in chemical property and easy to be synthesized, have no carcinogenecity and dispense with virus vector. Studies have shown that the immunogenicity of multipeptide vaccines could be enhanced by use of immunoadjuvants, joining dendritic cells (DCs), full-length or epitope-superposited antigen peptides, costimulatory molecules and cellpenetrating peptides fusion, thereby improving anti-tumor effect. Certain achievements have been obtained in clinical treatment of melanoma by multipeptide vaccines, but problems including poor immunogenicity and human leukocyte antigen (HLA) phenotype restriction may require further study.

Background: Our previous findings showed that miR-33 expressed abnormally in clinical specimens of melanoma, but the exact molecular mechanism has not been elucidated. Object: To determine miR-33's roles in melanoma and confirm whether HIF-1α is a direct target gene of miR-33a. Methods: First miR-33a/b expression levels were detected in HM, WM35, WM451, A375 and SK-MEL-1. Then lentiviral vectors were constructed to intervene miR-33a expression in melanoma cells. Cell proliferation, invasion and metastasis were detected. A375 cells mice model was performed to test the tumorigenesis of melanoma in vivo. Finally the dual reporter gene assay was carried out to confirm whether HIF-1α is a direct target gene of miR-33a. Results: MiR-33a/b exhibited a lower expression in WM35, WM451, A375 and SK-MEL-1 of the metastatic skin melanoma cell lines than that in HM. Then inhibition of miR-33a expression in WM35 and WM451 cell lines could promote cell proliferation, invasion and metastasis. Conversely, increased expression of miR-33a in A375 cells could inhibit cellproliferation, invasion and metastasis. In vivo tests also confirmed that overexpression of miR-33a in A375 cells significantly inhibited melanoma tumorigenesis. Finally, we confirmed that HIF-1α is a direct target gene of miR-33a. Conclusion: The newly identified miR-33a/HIF-1α axis might provide a new strategy for the treatment of melanoma.

To confirm whether flotillin 2 (FLOT2) is a direct target of miR-34a and miR-34a/FLOT2 pathway plays a key role in melanoma proliferation and metastasis.First, miR-34a and FLOT2 expressions were both detected in human tissues and cell lines by qRT-PCR. Then, after transfection of mimics/inhibitor of miR-34a into melanoma cell lines, MTT, colony formation, scratch migration assays and transwell invasion assays were performed to evaluate the impact of miR-34a on cell proliferation and metastasis. Western blot, qRT-RCR and dual luciferase reporter gene assays were carried out to confirm whether FLOT2 is a direct target gene of miR-34a. In functional recovery experiments, proliferation and metastasis ability of WM35 and WM451 was tested after being co-transfected with miR-34a inhibitor/si-FLOT2 or miR-34a mimics/FLOT2 cDNA to confirm that FLOT2 is downregulated by miR-34a.The miR-34a significantly lower-expressed in metastasis melanoma tissues compared to in situ melanoma, nevi and normal skin whereas FLOT2 has an opposite trend. The level of miR-34a and FLOT2 in different melanoma cell lines was also tested and found that metastatic melanoma cell lines has lower miR-34a expression and higher FLOT2 expression compare to in situ melanoma cell line. MiR-34a overexpression profoundly inhibits WM451 cell proliferation and metastasis, whereas miR-34a reduction had a promoting effect to proliferation and metastasis of WM35. Results of Western blot, qRT-RCR and dual luciferase reporter gene assays revealed that FLOT2 is a direct target gene of miR-34a. Furthermore, overexpression/blockage of FLOT2 could attenuate effect of miR-34a overexpression/inhibition which indicated miR-34a suppresses melanoma biological behavior partially through FLOT2 inhibition.Our study confirmed that miR-34a is involved in the tumor inhibition of melanoma by directly targeting FLOT2 gene. This finding provides potential novel strategies for therapeutic interventions of melanoma.

Diffusion and migration of elements are commonly observed in the fabrication of multilayer thin-film devices, including those of STT-RAM. The CoFeB/MgO/CoFeB tri-layer thin-film stack has been widely used in the design of STT-RAM devices as the functional magnetic-tunnel-junction (MTJ) structure. Such issues faced in the fabrication of these devices have been extensively researched from the stand point of engineering the materials property and structure to achieve the best MTJ performance. In this work, we conducted a detailed examination of the chemical-state change of the Ta and B in a CoFeB/MgO/CoFeB/Ta film stack by using x-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry. We showed that the chemical-state change of Ta and B is a result of the Ta diffusion phenomena through the CoFeB/MgO/CoFeB tri-layer structure. In particular, we report the evidences of the formation of TaBxOy compound at some considerable depth away from the Ta layer. Also of value to XPS spectroscopy, the Ta binding energy for such TaBxOy compound is reported for the first time.

In this paper, orthogonal projection method OPM is proposed to calculate a few eigenpair derivatives of large real symmetric matrices, if the eigenvalues are simple. By projecting large matrix-valued functions to small subspaces dependent on parameter, linear systems of equations for eigenpair derivatives are greatly reduced from the original matrix size. Error bounds on the eigenpairs and their derivatives computed by OPM are established with trivial conditions, which is one of the main contributions of this paper. It is shown that if the deviations from small subspaces to invariant subspace corresponding to the desired eigenvalues and the derivatives of residuals of the computed eigenpairs tend to zero, then the computed eigenpairs and their derivatives converge to the desired eigenpairs and their derivatives. Next, a strategy to generate small subspaces in OPM is given based on the implicitly restarted Lanczos process IRLP for symmetric matrix-valued function. Convergence of the IRLP-based OPM is analysed in detail, which is the main emphasis of this method. Finally some numerical experiments are reported to show the efficiency of our method.

Heat assisted magnetic recording (HAMR) is a promising choice to surpass the super-paramagnetic limit in magnetic recording and to allow continued increase in the areal recording density of hard disk drive. However, lubricant depletion on disk surface might be a problem in HAMR due to high temperature during writing process. In this work, depletion of four types of commercial lubricants on our HAMR media has been evaluated under equivalent HAMR conditions. Linear relationships between the lubricant depletion depth and the logarithm of the equivalent laser heating time have been established for these lubricants. The depletion depths of the lubricants at different laser heating durations are predicated. It is found that the performance of the four evaluated lubricants is acceptable in respect of lubricant depletion depth by hypothesizing the total heating duration for a given point on the media over the lifetime of the drive is 106 ns.

Through a novel temperature measurement method, this paper studies the lubricant film property subjected to heat-assisted magnetic recording (HAMR) laser heating. The material characterization of lubricant film under HAMR ultra-fast heating rate and ultra-short heating period condition has been compared with that after conventional thermal heating. The relationship of lubricant degradation and decomposition with the heating rate and heat duration and the reaction of the lubricant with the metal used for the temperature sensor has been studied and discussed.