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The effect of microstructure on the oscillating interlayer coupling PtMn-biased bottom spin valves is evaluated. The results show that smoothening films result in a stronger oscillating exchange interlayer coupling (OXC) and coupling, both when suppressing long-range and short-range roughness and in Neel coupling, was sensitive to long-range waviness for the given spacer thickness range.

OBJECTIVE: To explore the underlying mechanism of ncRNA (MIR22HG) in thyroid papillary carcinomas. PATIENTS AND METHODS: 40 pairs of thyroid papillary carcinomas tissues and adjacent normal tissues were collected from patients of the First Affiliated Hospital of Guangxi Medical University, who underwent oral surgery. qRT-PCR was applied to detect the expression of MIR22HG, miR-24- 3p and p27kip1 in tissues and cells. Western blot was used to measure the protein level of p27kip1 in tissues and cells. Kaplan-Meier plot was used to analyze the overall survival rates in thyroid papillary carcinomas. Pearson's correlation analysis was used to analyze the correlation relationship among MIR22HG, miR-24-3p and p27kip1 expression. Flow cytometric assay was applied to measure cell apoptosis. Transwell assay was used to assess cell migration and invasion abilities. Luciferase reporter assay was applied to verify the molecular relationships among MIR22HG, miR-24-3p and p27kip1 in thyroid papillary carcinomas. RESULTS: L ncRNA M IR22HG a nd p 27kip e xpressed low while miR-24-3p expressed high in thyroid papillary carcinomas and cells. Overexpression of MIR22HG inhibited cell proliferation, migration and invasion, whereas promoted cell apoptosis in thyroid papillary carcinomas cells. However, these effects were reversed by upregulation of miR-24-3p. Further exploration showed that the promoted effects of miR-24- 3p mimics on thyroid papillary carcinomas cells were suppressed by enhancing p27kip1 expression. Meanwhile, MIR22HG induced p27kip1 expression by binding miR-24-3p in thyroid papillary carcinomas. CONCLUSIONS: MIR22HG inhibited cell growth through modulating p27kip1 by decreasing miR-24-3p expression in thyroid papillary carcinomas, providing a new modulate mechanism and therapeutic targets in thyroid papillary carcinomas. [ABSTRACT FROM AUTHOR]

Nano-Oxide Layers (NOL) have been introduced recently as a means to enhance the degree of specular scattering at the outer surfaces in a spin-valve, while still using metallic antiferromagnets such as PtMn or IrMn. A key requirement of the NOL layer in the pinned layer is to be able to provide strong ferromagnetic coupling between two ferromagnetic layers. In this paper, a quantitative study of the ferromagnetic interlayer coupling over the NOL-layer is presented. A Stoner-Wohlfarth model is developed to allow for quantitative analysis. The effect of different metal deposition methods (PVD or IBD), different pinning structures (PtMn and IrMn; simple and synthetic) and different oxidation methods on the coupling is compared. Index Terms--Magnetoresistance, specular reflection, spin-valve.

A large giant magnetoresistance (GMR) value of 7.5% has been measured in simple NiFeCo(1)/Cu/NiFeCo(2) sandwich films grown on a 30 [Angstrom] Cr seed layer. This spin-valve GMR effect is consistent with the differential switching of the two NiFeCo layers due to an enhanced coercivity of the NiFeCo(1) layer grown on the Cr seed layer. A change in growth texture of the NiFeCo(1) layer from fcc (111) to bcc (110) crystallographic orientation leads to an increase in magnetic anisotropy and an enhancement in coercivity. The GMR value increases to 8.7% when a thin CoFe interfacial enhancing layer is incorporated. Further enhancement in GMR values up to 14% is seen in the sandwich films by nano-oxide layer formation. The specular reflection at the oxide/magnetic layer interface further extends the mean free path of spin-polarized electrons. Index Terms--GMR, sandwich, spin-valve, seed layer, coercivity, nano-oxide layer, specular reflection.

We investigated the effect of aluminum thickness on RA (resistance [multiplied by] area product) and MR ratio in spin-dependent tunnel junctions. Very low RA values below 40 [Omega]/[[micro]m.sup.2] and a maximum MR ratio of 6% were obtained in [Ni.sub.81][Fe.sub.19]/[Al.sub.2][O.sub.3]/[Ni.sub.81][Fe.sub.19] tunneling junctions fabricated using natural oxidation of aluminum. The MR ratio significantly increased with use of [Co.sub.90][Fe.sub.10] electrodes. Using natural oxidation of 6 [Angstrom] aluminum, RA and MR ratio of these junctions are ~50 [Omega][[micro]m.sup.2] and ~28%, respectively. The MR ratio and the junction resistance strongly depend on the aluminum thickness. The optimum thickness of aluminum is 6-7 [Angstrom] for natural oxidation. Index Terms--Giant magnetoresistance, magnetic films and devices, magnetic materials for heads, magnetic spin tunneling.

IrMn exchange biased bottom spin-valve films of structure Ta/underlayer/ IrMn/CoFe/Cu/CoFe/NiFe/Ta were prepared using ion beam deposition techniques. The exchange bias field exhibits strong underlayer thickness dependence. For the first time, a large exchange energy of 0.29 erg/[cm.sup.2] was measured in spin-valve films exchange biased by a disordered antiferromagnet, comparable to the values usually obtained in spin-valve films exchange biased by an ordered antiferromagnet. We have conducted a comparative study on both bottom and top exchange biased spin-valve and ferromagnetic/antiferromagnetic bilayer films. The results indicate that the exchange field obeys very well the inverse pinned layer thickness law over a thickness range from 200 [Angstrom] down to 10 [Angstrom]. The exchange energy for bottom spin-valve films is, however, a factor of two larger than that for top spin-valve films. When normalized, the exchange field exhibits the same temperature dependence for both bottom and top spin-valve films. The enhancement in exchange biasing is mainly attributed to an enhanced texture for fcc (111) crystallographic orientation of the IrMn layer in bottom spin-valve films. Index terms-exchange bias, ion beam deposition, bottom spin-valve, underlayer, IrMn

We have designed and fabricated dual spin valve heads with synthetically pinned layers. They have excellent sensitivity. The read-back waveform has a small asymmetry and that is also insensitive to the bias current. The read gap length is of 0.14 [micro] m and the write gap length is of 0.2 [micro] m. The read heads have a nominal magnetic trackwidth of 0.5 [micro] m and a nominal write magnetic trackwidth of 0.8 [micro] m. The write heads were conventional inductive heads with their pole geometry defined by focused ion beam (FIB) technology. The dual spin valve heads have achieved an areal read/write density as high as 14.5 Gb/[in.sub.2] at a data transfer rate of 23~24 MB/sec. The sensitivity of the readers is as high as 3.6 mVp-p/[micro] m. The bit aspect ratio is as high as 14. Index Terms--Dual spin valve head, GMR reader design concept, GMR head thermal stability, synthetic antiferromagnetic-pinned layers.

We have observed a 30% of enhancement in coercivity, [H.sub.c], or a 40% increase in remnant magnetization in ion beam deposited (IBD) Cr/CoPt films as compared to IBD Cr/CoCrPt films. In addition, the magnetic properties of these hard bias films exhibit a strong dependence of on substrate and underlayer. Higher coercivity values associated with enhanced hcp Co (10??0) crystallographic orientation were measured in films grown on substrates in the preference order of glass, Si/[Al.sub.2][O.sub.3] and Si. CoPt films grown on CrV underlayer show lower [H.sub.2] values than films deposited on Cr underlayer. [H.sub.c] exhibits a maximum with increasing Cr underlayer thickness for both Cr/CoPt and Cr/CoCrPt films. This Cr thickness dependence of [H.sub.2] is correlated well with that of Co (10??0)/(0002) x-ray diffraction peak intensity ratio, indicating the role of crystallographic texture in control of coercivity of IBD hard bias films. Index Terms--IBD, Hard bias film, Microstructure, MR recording head.

Abstract: Objective: The purposes of this study were to explore both the prognostic value of pathologic grade and the relationships between differentiation and clinicopathological characteristics in oral squamous cell carcinoma. Methods: This retrospective cohort study included the records of 2036 patients with oral squamous cell carcinoma who were surgically treated from June 1999 to December 2011. Chi‐square test, Kaplan–Meier analysis, and Cox proportional hazards regression model were performed for statistical analysis. Results: Many clinicopathological characteristics were associated with pathologic grade. Kaplan–Meier analysis showed that well‐differentiated tumors had a better prognosis than the other two grades. Cox regression model showed that differentiation was an independent risk factor for prognosis in patients with early stage, but not with advanced stage. The predictive abilities of pathologic grade, T stage, N status, and lymph node ratio were similar, but the presence of extracapsular spread and perineural invasion were stronger prognostic factors than pathologic differentiation. Conclusions: Pathologic grade was found to be an independent risk factor for early‐stage oral squamous cell carcinoma, but not for advanced stage. Many important clinicopathological characteristics were associated with histological classification; however, its prognostic value was limited. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the prevalence of general anxiety disorder (GAD) among postmenopausal women with symptomatic pelvic organ prolapse (POP) and to identify its associated factors.Methods: A cross-sectional study was conducted among postmenopausal women with symptomatic POP. Sociodemographic data and medical histories were obtained. Participants completed the POP Quantification (POP-Q), the Pelvic Floor Impact Questionnaire-7 (PFIQ-7), and the Pelvic Floor Distress Inventory (PFDI-20) measures. Measures of GAD were obtained using the Generalized Anxiety Disorder-7 (GAD-7). The data were analyzed using independent sample t-tests, the Mann-Whitney U-test, χ2 tests, Fisher's exact tests and logistic regression.Results: Of the 177 participants interviewed, 19.2% had symptoms of GAD. There were no statistically significant differences in the sociodemographic characteristics or the POP-Q stage between women with and without GAD (p > 0.05). GAD was significantly associated with higher PFDI-20 and PFIQ-7 subscale scores (p < 0.05). After multiple logistic regression analyses, only the PFIQ-7 subscale UIQ-7 (odds ratio = 1.025, 95% confidence interval 1.007-1.043, p = 0.005) and the PFDI-20 subscale CRADI-8 (odds ratio = 1.025, 95% confidence interval 1.004-1.047, p = 0.021), which represented the impact on quality of life from lower urinary tract symptoms and the distress caused by bowel dysfunction, were risk factors that were independently associated with GAD.Conclusions: GAD is prevalent in almost one-fifth of postmenopausal women with symptomatic POP. GAD is not associated with the severity of the POP-Q stage but is associated with higher scores for lower urinary tract and bowel dysfunction caused by POP. [ABSTRACT FROM AUTHOR]

Interlayer coupling in spin-valve films is usually dominated by the ferromagnetic Néel coupling of a magnetostatic nature due to interfacial roughness. The addition of N[SUB2] as a second sputter gas species during deposition of thin layers in PtMn bottom spin-valve films has shown effectiveness in the reduction of interfacial roughness and, therefore, control of ferromagnetic Néel coupling. The interlayer coupling field has been more effectively reduced from an original 38.8 Oe down to 6.1 Oe at a Cu spacer layer thickness of 24 Å with the addition of 4 sccm N[SUB2] gas during the Cu spacer layer deposition. In addition to higher giant magnetoresistance values over 10% at thinner Cu spacer layer thicknesses, a pronounced oscillatory dependence of the interlayer coupling field on Cu spacer layer thickness has been observed. Apparently, nitrogen serves as surfactant and helps layer-by-layer growth of Cu on a CoFe pinned layer, resulting in smoother CoFe/Cu and Cu/CoFe interfaces. [ABSTRACT FROM AUTHOR]

Two sets of PtPdMn exchange biased films Ta 50 Å/CoFe 100 Å/PtPdMn (t[sub AF]) Å/Ta 50 Å, with PtPdMn thickness, t[sub AF]=350, 600 Å, were deposited on Si substrates by dc magnetron sputtering techniques. After magnetic annealing, these two sets of films exhibited values of exchange bias field, H[sub ex]=229 and 254 Oe, respectively. The PtPdMn layer was then thinned to various thicknesses from 600 down to 50 Å by ion beam etching. H[sub ex] does not retain its original value. It decreases with decreasing t[sub AF] and becomes zero at t[sub AF]∼75 Å. In addition, we have observed that the training effect or the anomalous hysteresis loss becomes more pronounced with decreasing t[sub AF]. This confirms that not only face-centered-tetragonal phase but, more critically, t[sub AF] plays role in determining exchange biasing and its thermal stability. The blocking temperature, T[sub B], appears unaffected by the thinning of the PtPdMn layer, and no apparent change occurs in the local blocking temperature distribution, as suggested by the finite size effect. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The influence of base pressure, P[sub b], on physical properties of FeMn exchange biased spin-valve films was studied by varying P[sub b] over two decades from 3×10[sup -8] to 7×10[sup -6] Torr. Giant magnetoresistive value shows a slight increase with increasing P[sub b] until a large decrease occurs at P[sub b]>3.3×10[sup -6] Torr. Exchange bias field and blocking temperature remain constant in the base pressure range between 3×10[sup -8] and 5×10[sup -7] Torr before a large reduction appears. Our results indicate an upper limit for base pressure, [sup u]P[sub b]approx. 5×10[sup -7] Torr, above which significant spin-valve performance modification and deterioration in the crystallographic texture begin as a result of the contamination both at the ferromagnetic/antiferromagnetic interface and in the bulk of FeMn layer. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this article, we report the magnetic properties of ultrathin (15–200 Å) NiFe and CoFe films deposited using ion beam deposition techniques. They are symmetrically sandwiched between Ta, Cu, or Ta/Cu under and capping layers. NiFe and CoFe films grown between Ta/Cu and Cu/Ta bilayers exhibit the smallest magnetic thickness loss of about 1 Å. This interfacial magnetic dead layer thickness, t[sub 0], is about 5 Å for Cu-sandwiched films and about 15 Å for Ta-sandwiched films. As the film thickness becomes thinner than 100 Å, the magnetic properties are found to be more sensitive to the choice of material and growth environment. CoFe films show an interfacial contribution, λ[sub i], about ten times larger than that for NiFe films. Among others, NiFe and CoFe films sandwiched by Ta/Cu and Cu/Ta bilayers exhibit the smallest values of λ[sub i]. The magnetic anisotropy in Ta-sandwiched CoFe films appears to be predominantly magnetoelastic in nature. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]