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Al and N K-edge x-ray absorption near-edge structure (XANES), scanning photoelectron microscopy (SPEM) and x-ray emission measurements were performed on AlN nanotips grown on p- and n-type Si substrates (p-AlN and n-AlN). Features and intensities in the Al and N K-edge XANES spectra of these AlN nanotips overall are similar. In contrast, the intensities of the valence-band SPEM spectra of p-AlN are apparently larger than those of n-AlN, which indicates that the valence-band density of states of p-AlN exceeds that of n-AlN. This result may be related to the observed enhancement of field-emission intensity of AlN nanotips grown on the p-type Si substrate.

In this paper a precise approach is used to extend and analyze the article published by Padmanabhan and Vrat (1990) in the International Journal of Systems Science. Utilizing this approach, we develop a criterion for existence and uniqueness of the optimal solution of the total cost function. If the criterion cannot be satisfied, this model degenerate to an inventory model with one cycle. In such case, the article shows that a longer stock shortage time would lower the total cost. Therefore, we evaluate the cost variation under different allotted times to provide decision-makers with strategies to balance the time and cost. We present illustrations to demonstrate the exactness of this process.

We report O K -, Ca K - and L 3,2 -, and Ti L 3,2 -edge X-ray absorption near edge structure (XANES) spectra of Ba 1− x Ca x TiO 3 ( x =0, 0.01, 0.08, and 1) and the electronic properties inferred from these XANES spectra. The spectra of O K -, Ca L 3,2 - and Ti L 3,2 -edges show characteristic spectral features attributable to the t 2 g and e g bands. The Ti and Ca L 3,2 -edge spectra contain two sets of L 3 and L 2 features with a L 3 – L 2 separation of about 5.5 and 3.4 eV, respectively. We also observe a pre-edge feature in the Ca K -edge spectra and drastically reduced t 2 g features in the Ca L 3,2 -edge spectra. Our XANES spectra reveal that the Ca 3 d bands are low-lying and the Ca 3 d t 2 g bands are partially occupied.

We present studies of orbital magnetic moments of CrO 2 and Fe 3 O 4 by measuring magnetic circular dichroism (MCD) in soft X-ray absorption. The results show that Fe 3 O 4 exhibits large orbital moments, as a consequence of the strong Coulomb interactions of Fe 3d electrons. In contrast, orbital moments of Cr in CrO 2 are nearly quenched, revealing that Cr 3d electrons are strongly hybridized with O 2p electrons and more delocalized as compared with those of Fe in Fe 3 O 4 . Comparing the MCD data with the band structure calculations based on local spin density approximation with on-site Coulomb energy U taken into account, we conclude that to include the on-site Coulomb interactions of 3d electrons is essential for adequately describing the electronic structure of CrO 2 and Fe 3 O 4 .

With polarization-dependent soft X-ray absorption, we determined the orbital character of occupied and the lowest unoccupied eg orbitals of prototype single-layered perovskite LaSrMnO4. Our measurements indicate that LaSrMnO4 exhibits strong orbital polarization in the eg states of Mn3+ sites, leading us to conclude that LaSrMnO4 has a “ferro-orbital” ordering of 3z2-r2. We found that linear dichroism in soft X-ray absorption is an effective experimental method to identify the nature of orbital ordering in transition-metal oxides such as manganites.

To measure spin-polarized core-level electron spectra, a spectrometer equipped with a highly efficient retarding-potential Mott spin polarimeter using undulator-based soft-x-ray beamlines has been set up. With a thin film of Au as a target this polarimeter has an efficiency estimated to be ∼2×10−4. The performance of this system for spin-polarized spectroscopy has been tested using core-level spin-polarized photoemission of magnetic and nonmagnetic thin films excited with linearly and circularly polarized light, respectively. Measurements using a new spin-resolved absorption technique are also discussed.

We have measured B K-edge X-ray absorption spectra of Mg 1-x Al x B 2 (x=0.0 ~ 0.4) using bulk-sensitive total fluorescence yield (TFY) at room temperature and 30 K. In contrast to previous reports no peaks near 192 eV and 194 eV could be observed after repeated scraping, indicating their origin being due to surface contamination. These clean spectra show a peak right above the absorption threshold, anticipated from transition to the unoccupied B 2p states. Except in the intermediate Al doping range of x ~ 0.1 to 0.28 the threshold peak intensity decreases, consistent with pσ-hole filling. The increase of peak intensity in the intermediate range is correlated with structural phase transition.

We present a near-field optical study of TiO2 nanodisks by fluorescence scanning near-field optical microscopy. The localization of light and the fluorescence enhancement near the dielectric structures are visualized with a lateral resolution of ∼λ/5 using an Er/Yb-codoped fluorescent nanocrystal glued at the end of a sharp scanning tip. We observed that the intensity patterns strongly depend on the disk size, forming lobes for a diameter close to the wavelength and a single bright spot for smaller structures. Although the experiments were performed out of resonance, a maximum fluorescence enhancement of 2.3 was observed near 700 nm-wide disks. The evolution of the fluorescence pattern as a function of the disk size is in good agreement with the near-field maps calculated by the finite-difference time-domain method, in both two and three dimensions above the structures.

In this study, the interfacial interactions between sludge flocs and a rough membrane surface in a submerged membrane bioreactor were investigated. Models describing these interfacial interactions were firstly proposed based on the surface element integration (SEI) method. Surface properties of sludge flocs and membrane were experimentally determined to simulate the models through composite Simpson’s rule. It was found that, roughness on membrane surface significantly decreased interaction strength, which enabled the sludge flocs to more easily attach on and detach from the rough membrane surface. Further analysis showed that the value of total interaction energy increased with asperity radius, while the strength of total interaction energy decreased with asperity height. Results also demonstrated that increase in floc size would significantly decrease the attractive specific total interaction with rough membrane surface. It was revealed that there existed a critical asperity radius above which the total interaction energy in certain separation distance coverage was continuously repulsive, facilitating membrane fouling control in MBRs. This study demonstrated the possibility to mitigate membrane fouling by “tailoring” membrane surface roughness.

We used particle bombardment to cotransform mature seed-derived rice callus (Oryza sativa L., ssp. japonica, cv. Eyi 105) with plasmids containing the linked marker genes gusA and hpt, and the ap1 gene encoding an amphipathic protein previously shown to delay the hypersensitive response induced in non-host plants by the pathogen Pseudomonas syringae pv. syringae (Pss). Thirty-two independent lines of transgenic rice plants were regenerated, and 27 of these lines carried all three transgenes as shown by molecular analysis. A bacterial blight inoculation test was carried out on ten lines. In each case, plants carrying the ap1 gene showed enhanced resistance to Xanthomonas oryzae pv. oryzae (Xoo) race 6 at various levels. This suggests the ap1 gene could be a useful candidate for genetic engineering strategies in rice to provide bacterial blight resistance.

An experimental investigation of near-surface flow beneath gravity-capillary waves (4.21–6.70 Hz) is presented. In this frequency regime, there exist visible parasitic capillary ripples, especially along the forward face of the underlying waves, if the steepness exceeds some moderate value. Relatively strong vortices are generated by these progressive waves, and for the first time their velocity fields are measured, their vorticity fields are calculated, and the results reported. A relevant theoretical model, first introduced by Longuet-Higgins, is also discussed and wherever possible compared to the experiments. Numerical simulations by Mui and Dommermuth are examined as they relate to these experiments, and it is shown that qualitative agreement exists between the experiments and the analytic-numerical predictions.

Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P = .05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (

Objective: The difference in histologic patterns of lung cancer between men and women in Taiwan may be associated with the heterogeneity in causal factors of lung cancer between the sexes. Methods: Cases consisted of 236 male and 291 female incident cases with newly diagnosed and histologically confirmed primary carcinoma of the lung, and were compared to one or two individually matched controls. Results: Cigarette smoking, occupations, and previous tuberculosis history were found to independently correlate with an elevated risk of squamous/small cell carcinoma and adenocarcinoma for male patients. However, there was little difference in the effect of these risk factors except smoking. The use of fume extractors in the kitchen, and the habit of waiting to fry after the fumes were emitted, separately explained the majority of the attributable fraction of female squamous/small cell carcinoma (28.2%) and adenocarcinoma (47.7%). With the exception of a kitchen with fume extractors and a clinical history of tuberculosis, the environmental causal factors of lung cancer were heterogeneous between these two histologic cell groups. Conclusions: Our results suggested that the causal factors of lung cancer might be specific for the type of tumor concerned. The gender-specific risk factors of lung cancer could partly explain the difference in cell-type distribution between men and women.

BACKGROUNDPeptic ulcers with active bleeding or a non-bleeding visible vessel require aggressive endoscopic treatment.AIMSTo determine whether endoscopic adrenaline injection alone or contact probe therapy following injection is a suitable treatment for peptic ulcer bleeding.METHODSA total of 96 patients with active bleeding or non-bleeding visible vessels received adrenaline alone, bipolar electrocoagulation alone, or combined treatment (n=32 in each group).RESULTSInitial haemostasis was not achieved in one patient in the adrenaline group, two in the gold probe group, and two in the injection gold probe group (p>0.1). Rebleeding episodes were fewer in the injection gold probe group (2/30, 6.7%) than in the gold probe group (9/30, 30%, p=0.04) and in the adrenaline group (11/31, 35.5%, p=0.01). Treatment failure (other therapy required) was rarer in the injection gold probe group (4/32, 12.5%) than in the adrenaline group (12/32, 37.5%, p=0.04). The volume of blood transfused after entry of the study was less in the injection gold probe group (mean 491 ml) than in the adrenaline group (1548 ml, pCONCLUSIONSFor patients with peptic ulcer bleeding, combined adrenaline injection and gold probe treatment offers an advantage in preventing rebleeding and decreasing the need for blood transfusion.

OBJECTIVE: We describe CT findings after laparoscopic repair of ventral hernia with emphasis on formation of postoperative fluid collections that can mimic recurrent bowel herniation or infected postoperative fluid collections. CONCLUSION: The porous property of the mesh used in laparoscopic repair of ventral hernia allows reaccumulation of fluid in the existing hernia sac or spaces in the subcutaneous tissues that can be created by laparoscopic manipulation. These fluid collections should be expected and are differentiated from infected fluid collections or hernia recurrence by clinical presentation, laboratory data, and lack of ancillary features associated with true hernia such as presence of hernia sac, herniated mesentery, or bowel obstruction.

We present measurements of Mn L -edge resonant soft X-ray scattering on single-layered manganites with different sizes of cations. Orbital ordering of Pr 0.5 Ca 1.5 MnO 4 exhibits a stronger three-dimensional character and a dramatically enhanced transition temperature, as compared with those of La 0.5 Sr 1.5 MnO 4 . The c -axis correlation length of orbital ordering in Pr 0.5 Ca 1.5 MnO 4 is about half of the in-plane correlation length. Our results indicate that reduction in one-electron bandwidth and quenched disorder strongly enhances the stabilization of charge–orbital ordering.

This article reconsiders Gallego's minimax distribution-free procedure. He created a two-point distribution to serve the most unfavorable case for estimating the expected cost of lost sales. We provide a reasonable condition to insure the existence and uniqueness of the optimal solution and the convergence of Gallego's method.

New techniques are developed to improve the velocity flow-field measurement capability within a free-surface boundary layer region on which progressive capillary-gravity waves are present. Due to the extremely thin but rather vortical characteristics of the aforementioned boundary layer, conventional particle image velocimetry (PIV) methods fail to estimate velocity (and vorticity) vectors at an acceptable detection rate. This failure is a direct consequence of optimal PIV parameters that are difficult to achieve in practice for such flow situations. A new technique, Sub-pattern PIV, is developed. This method has features similar to both the super-resolution PIV (Keane et al. 1995) and the particle image distortion (PID) technique (Huang et al. 1993), but is predicated upon a very differential philosophy. Another difficulty that arises in experiments to investigate surface boundary layer flows is that the oscillating and deforming air–water interface has a mirror-like behavior that affects the images, and generates very noisy data. An alternative experimental setup that utilizes the Brewster angle phenomenon is adopted and the specular effects of the free-surface are removed successfully. This Brewster angle imaging, along with the Sub-pattern PIV technique, is used for the target application – a free-surface boundary layer investigation. It proved to be very effective. The methodology of both techniques is discussed, and the modified PIV procedure is validated by numerical probabilistic simulations. Application to the capillary-gravity wave boundary layer is presented in a subsequent paper.

OBJECTIVE. The purpose of this study was to evaluate the efficacy of Wallstents in treating inferior vena cava obstruction in hemodialysis patients. CONCLUSION. For the short and intermediate term, percutaneous placement of inferior vena cava Wallstents, followed by balloon angioplasty, is a safe and valuable technique for preserving the often limited central venous access in hemodialysis patients. To maintain patency, recurrent stenosis within the Wallstent can be treated with additional angioplasty.

The magnetic moments of disordered and ordered L10 Fe50Pt50 films were investigated using magnetic circular dichroism (MCD) and spin polarized full relativistic Korringa–Kohn–Rostoker (SPRKKR) calculations. The measurements showed that the spin magnetic moments of Fe in both ordered and disordered films were similar with a lower value than that obtained by SPRKKR calculations. Both films however showed larger orbital moments of Fe compared to the calculations. It is suggested that the spin magnetic moment of Fe in FePt thin films was insensitive to L10 ordering.

Samples of Ta/Cu 3 nm/IrMn 8 nm/Co/sub (FM1)/ 1 nm/FeO/sub x/ 1.6 nm/Co/sub (FM2)/ 2.5 nm/Ta were prepared using sputtering deposition. The exchange biasing direction of the films were set by postannealing in vacuum at 200 /spl deg/C for 15 min at a presence of 1 kOe. Hysteresis loops measured parallel (0/spl deg/) and perpendicular (90/spl deg/) to the annealing field show the existence of unidirectional anisotropy and uniaxial anisotropy, respectively. The presence of the uniaxial anisotropy at 90/spl deg/ induced a local energy minumum at 90/spl deg/. The effects of local energy minimum at 90/spl deg/ are more pronounced in the R-H loops measured at 20/spl deg/ where the coexistence of the two anisotropies results to an extra MR minimum near the zero field. With increasing positive field, the magnetization of the free layer is switched to the appllied field direction, accompanying the increase in MR. Further increase of the positive fields lead to the re-appearance of the MR minimum due to the alignment of the magnetization of FM2 and free layer.

The magnetic properties of a Co2FeAl/(Ga,Mn)As bilayer epitaxied on GaAs (001) are studied both experimentally and theoretically. Unlike the common antiferromagnetic interfacial interaction existing in most ferromagnet-magnetic semiconductor bilayers, a ferromagnetic interfacial interaction in the Co2FeAl/(Ga,Mn)As bilayer is observed from measurements of magnetic hysteresis and x-ray magnetic circular dichroism. The Mn ions in a 1.36 nm thick (Ga,Mn)As layer remain spin polarized up to 400 K due to the magnetic proximity effect. The minor loops of the Co2FeAl/(Ga,Mn)As bilayer shift with a small ferromagnetic interaction field of +24 Oe and -23 Oe at 15 K. The observed ferromagnetic interfacial coupling is supported by ab initio density functional calculations. These findings may provide a viable pathway for designing room-temperature semiconductor spintronic devices through magnetic proximity effect.

This paper presents a self-testing technique for split-capacitor-array SAR ADC. In the proposed mutual characterization methodology, the capacitor array is reconfigured so that one sub-array assists the bit weight extraction of the other. Taking advantage of the split-capacitor-array architecture, mutual characterization incurs much less area overhead than previous works. From obtained bit weights, the capacitor mismatch induced nonlinearity can be derived and further calibrated via external digital calibration. Simulation results show that the proposed technique achieves high DNL/INL estimation accuracy and substantially improves the SAR ADC linearity.

The magnetic properties of a Co2FeAl/(Ga,Mn)As bilayer epitaxied on GaAs (001) are studied both experimentally and theoretically. Unlike the common antiferromagnetic interfacial interaction existing in most ferromagnet-magnetic semiconductor bilayers, a ferromagnetic interfacial interaction in the Co2FeAl/(Ga,Mn)As bilayer is observed from measurements of magnetic hysteresis and x-ray magnetic circular dichroism. The Mn ions in a 1.36 nm thick (Ga,Mn)As layer remain spin polarized up to 400 K due to the magnetic proximity effect. The minor loops of the Co2FeAl/(Ga,Mn)As bilayer shift with a small ferromagnetic interaction field of +24 Oe and -23 Oe at 15 K. The observed ferromagnetic interfacial coupling is supported by ab initio density functional calculations. These findings may provide a viable pathway for designing room-temperature semiconductor spintronic devices through magnetic proximity effect.

Connection between orbital moment enhancement and exchange bias in a [Ni80Fe20/Mn]3 multilayer H.-C. Su,1 M.-J. Huang,1 H.-J. Lin,1,* C.-H. Lee,1,2 C.-T. Chen,1 C.-H. Liu,3 H.-F. Hsu,3 K.-W. Lin,3 and J. van Lierop4,† 1National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan 2Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan 3Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan 4Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada (Received 28 June 2012; published 2 January 2013)

The electronic structures of Nd1-xYxMnO3 (x=0-0.5) were studied using X-ray absorption near-edge structure (XANES) at the Mn L-3,L-2- and O K-edge along with valence-band photoemission spectroscopy (VB-PES). The systematic increase in white-line intensity of the Mn L-3,L-2-edge with doping, suggests a decrease in the occupancy of Mn 3d orbitals. The O K-edge XANES shows a depletion of unoccupied states above the Fermi energy. The changes in the O K-edge spectra due to doping reflects an increase in the Jahn-Teller distortion. The VB-PES shows broadening of the features associated with Mn 3d and O 2p hybridized states and the shift of these features to a slightly higher binding energy in agreement with our GGA + U calculations. The system shows a net shift of the occupied and unoccupied states away from the Fermi energy with doping. The shift in theoretical site-projected density of states of x=0.5 composition with respect to x=0 suggest a subtle change from a charge transfer to Mott-Hubbard type insulator. (C) 2013 Elsevier B.V. All rights reserved.

X-ray absorption near edge structure (XANES) spectra of thin-film CoSi 2 were measured at the Si K- and Co L 3 -edge. The Si K-edge spectrum for CoSi 2 showed a dramatic reduction of intensity in the first broad feature accompanied by an increase in intensity of a peaked feature at higher energies when compared to the spectrum for crystalline Si. We attribute these two features to the Si 1s photoelectron excitations to a broad Si 3p nonbonding band and a relatively narrow band of hybridized Si p - Co 3d antibonding states, respectively. The Co L 3 -edge white line spectrum for CoSi 2 reveals three distinct features which can be attributed to excitations to the unoccupied Co 3d nonbonding states and hybridized antibonding Co (3d, 4s) - Si p states.

Good surface quality is essential for the twin roll cast stainless steel strip to be directly cold-rolled. Thus, surface quality of AISI 304 stainless steel is one of the main problems for the twin roll strip casting process to be put into commercial production. The surface defects commonly appeared in the as-cast strip of twin roll process may include longitudinal and transverse cracks or wrinkles as well as unevenness which is mainly caused by gas trapping and surface vibration of meniscus between the two rolls. In this study, a modeling software was applied to simulate the flow behavior of molten pool at quasi-steady state in inclined twin roll casting and to investigate the relationship between flow characteriatics and surface quality of the produced thin strip. The flow characteristics was drawn from the calculated flow patterns and then correlated to the surface quality of thin strips produced in an experimental caster under the same casting condition as the calculations. Through this procedures, several correlations were then found. First, the surface wrinkles appeared on the thin strip when the pool levels were low. The problem was improbed with a higher pool level due to less flow violence nor meniscus fluctuation. Second, the recirculation with a large vortex occurring around the triple intersection point of the roll/melt/air three phases was the main cause for the slag and/or dross trapping. Third, by using a higher roll angle along with an inclined feeding position nearer to the lower roll, a much table flow on the meniscus surface could be obtained.

From May 1992 to February 1993, 22 cases of hypertensive putaminal haemorrhage (HPH) treated at our hospital were serially measured with transcranial Doppler (TCD) sonography. Among them, 13 patients underwent surgical intervention (3 stereotaxic surgery and 10 craniotomies), and 9 were conservatively treated. Most of the patients of the two operative groups had larger haematomas and developed clinical and/or neurological deterioration, which was the indication for subsequent surgery. Therefore the groups represent different clinical and physiological entities. On admission, the peak MCA velocities (Vs) in the surgical group (stereotaxic and craniotomy) were significantly lower than those in the conservative group (mean +/- S.E.M.: 38.33 +/- 4.26 and 42.00 +/- 2.62 cm/sec vs. 57.22 +/- 3.23 cm/sec; p0.005, respectively). The surgical group also had significantly lower diastolic (Vd) and mean (Vm) velocities than those of the conservative group (p0.001). Rather, the admission pulsatility indices (PI = (Vs-Vd)/Vm) in the surgical group were significantly higher than those of the conservative group (mean +/- S.E.M.: 1.42 +/- 0.04 and 1.31 +/- 0.09 vs. 0.95 +/- 0.01; p0.005, respectively). Time course velocity curves reached a peak around the 3rd hospital day in all the 3 groups. The Glasgow coma scale (GCS) scores positively correlated with the mean MCA velocities (n = 22; r = 0.63, p0.005; y = 2.04 x + 8.74), but negatively with PI values on admission (n = 22; r = -0.53, p0.05; y = 1.68-0.053 x). On the 7th hospital day, 2 patients with peak MCA velocities below 50 cm/sec had an unfavourable outcome. All the 3 patients in the stereotaxic group had higher peripheral resistance, as compared with those in conservative craniotomy groups (mean +/- S.E.M.: 1.28 +/- 0.13 vs. 0.99 +/- 0.07 and 0.87 +/- 0.06; p0.05, respectively). Our study supports TCD as a safe and valid monitoring method in patients with HPH. "Compromised cerebral haemodynamic status" (Vs50 cm/sec, Vd15 cm/sec, Vm25 cm/sec, PI1.15) may offer an aid in the decision for surgical intervention in HPH. Postoperatively, patients who made a favourable recovery had a significant increment in the MCA velocities in contrast to those severely disabled, whose MCA velocities remained low.

Ni and Fe L3,2-edge magnetic circular dichroism (MCD) and Cr K-edge x-ray absorption near-edge structure measurements have been performed for the Py/Cr(tCr)/Py (Py=Ni80Fe20) trilayers with tCr=5, 10, 15, 20, and 25 A. The MCD asymmetry ratios in the Ni and Fe L3-edges spectra are found strongly affected by the thickness of the Cr layer. The moments of the Fe and Ni 3d states are found, respectively, to decrease and increase suddenly when tCr increases beyond 20 A. The measured magneto-optical Kerr effect hysteresis loops show a ferromagnetic-to-antiferromagnetic phase transition at about the same Cr-layer thickness. The transition of the magnetic property is found to correlate with the structural transition of the Cr spacer layer from a pseudomorphic fcc-like structure to a bcc structure.

This investigation examined the cumulative survival rate of the implant-supported overdenture using two types of attachments in patients treated at Show Chwan Memorial Hospital Implant Center from 1992 to 2006. Fifty-one patients (30 men and 21 women) were treated with mandibular implant-supported overdentures. Attachment systems used were the Hader bar with bilateral, cast ERA attachments (Group A, 31 patients with 15 men and 16 women, 134 implants) and the Hader bar with bilateral, distal extension cantilevers (Group B, 20 patients with 15 men and 5 women, 85 implants). Two hundred and four implants remained at the end of the follow-up period. Among failed implants, 10 implants were in Group A (failure rate: 10/134 = 7·5%), whereas five implants were in Group B (failure rate: 5/85 = 5·9%). Sixty-six point seven per cent (10/15) of failed implants were placed in the distal anterior mandible, and 33·3% (5/15) were placed in the middle anterior mandible. Survival was also examined with respect to condition of the opposing arch. Patients wearing a maxillary removable partial denture had the highest implant failure rate (5/51 = 9·8%), whereas the failure rate of the maxillary complete denture group was only 5·7%. The most frequent need for maintenance was wear over patrix component of ERA or Hader clip (n = 56). Eight patients experienced connector fracture between ERA and Hader bar, and one experienced distal extension cantilever fracture. The implant-supported overdenture can be an effective and reliable alternative to the conventional complete mandibular denture. Fewer prosthetic complications were seen in overdentures retained with distal extension cantilever attachments.

The social network has been a very popular research area in the recent years. Lot of people at least have one or more social network account and use it keep in touch with other people on the internet and build own small social network. Thus, the effect and the strength of social network is a very deep and worth to figure out the information delivery path and apply to digital learning area.

A type of GaAs-based ferromagnetic semiconductor, (Ga, Cr)As, was successfully prepared by low-temperature molecular-beam epitaxy. The (Ga, Cr)As thin film shows a flat surface up to the Cr content x=0.18. However, when Cr content x exceeded 0.20, the roughness of the film became larger. The ferromagnetic ordering of the semiconductor sample with the Cr content of x=0.11 was observed. The electronic structures of (Ga, Cr)As were characterized by x-ray absorption spectroscopy (XAS). The XAS spectra show different line shapes in different Cr content.

Zinc-blende CrAs/GaAs multilayers were grown by molecular beam epitaxy. It was certified that each CrAs layer maintains an epitaxial relationship with the zinc-blende GaAs structure judging from the reflection high-energy electron diffraction observation. The film contains thicker zinc- blende CrAs layers in total than the CrAs thin film directly grown on the GaAs substrate which has the critical thickness of 3 nm. It was clarified that the optimum thicknesses of CrAs and GaAs to keep a good epitaxial relationship are 2 ML and 2 ML, respectively. The electronic structure of the multilayer is thought to be close to that of the (Ga, Cr)As thin film which has 50% of Cr content judging from x-ray absorption spectroscopy measurements.

Infection is a major medical problem in patients with acute stroke. Recent evidences suggest that statins reduce infection-associated complications. The purpose of this study was to examine the influence of statin treatment on mortality and functional outcomes in patients with stroke-associated infection.In this prospective observational cohort study, 514 patients with acute ischaemic stroke or transient ischaemic attack (mean age, 74 ± 11 years; men, 48%) with infection occurring in the first 7 days after admission were included. We examined the effect of in-hospital statin treatment on mortality and favorable functional outcome (modified Rankin Scale score ≤2) at 3 months follow-up. Infection occurred at 0.93 ± 1.49 days after admission. All patients had not received statin treatment prior to admission, and 121 patients (24%) received statin at 1.71 ± 1.28 days after admission. Follow-up at 3 months was completed for 511 patients (99%). National Institutes of Health Stroke Scale score and Charlson index were the most important independent predictors of mortality and functional outcome. Univariate [hazard ratio (HR), 0.82; 95% confidence intervals (CI), 0.47-1.42] and multivariate (HR, 1.68; 95% CI, 0.79-3.56) Cox regression analysis showed that statin did not significantly decrease the morality. In propensity analysis, statin treatment still had no significant association with mortality (HR, 1.54; 95% CI, 0.68-3.47) in the multivariate analyses after adjusting for age, sex, and propensity score. Statin use was not associated with a better functional outcome or survival in patients with stroke-associated infection.

We investigated the magnetic nature of Fe(1/4)TaS2 using x-ray absorption spectroscopy, photoemission spectroscopy, and first principles band calculations. The results show a large unquenched orbital magnetic moment (∼1.0 μ(B)/Fe) at intercalated Fe sites, resulting in a gigantic magnetic anisotropy (H(A)≃60 T). The magnetic coupling is well understood in terms of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, suggesting a novel RKKY ferromagnet with Ising-type spin states. We also found that this indirect exchange coupling between the neighboring Fe spins is ferromagnetic and maximized at the Fe-Fe distance of 2×2 superstructure.

An elite maize inbred line with high tolerance to low phosphorus, 178, was studied for constructing root library and analyzing some genes closely related to phosphorus (P) deficiency using SSH and Semi-quantitative RT-PCR. As a result, 3648 preliminary clones were obtained for root library under stress of P deficiency. By DNA sequencing of 34 random clones, we obtained 23 unique EST sequences which are involved in functions of root cell structure, tolerance and defense, protein modification and composition, transcription regulation, metabolism, and other unknown aspects. Five representative genes were further analyzed for their expression models. The results suggested that the molecular mechanism to adapt P deficiency in maize, performed by multi-genes with different contributions, is similar to rice, Arabidopsis and soybean. The expression order of 5 low P tolerant genes in maize root was PAP, GCS, TOM, PDI and AIP. And it was considered preliminarily that physiological and biochemical changes were prior to morphologic changes in maize root and the essential tolerance to low P may be determined by extending absorption of P to wide soil range through adaption of root architecture and root secretions, which is the greatest difference between tolerant and sensitive maize varieties under low P stress.

We investigated the magnetic nature of Fe(1/4)TaS2 using x-ray absorption spectroscopy, photoemission spectroscopy, and first principles band calculations. The results show a large unquenched orbital magnetic moment (∼1.0 μ(B)/Fe) at intercalated Fe sites, resulting in a gigantic magnetic anisotropy (H(A)≃60 T). The magnetic coupling is well understood in terms of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, suggesting a novel RKKY ferromagnet with Ising-type spin states. We also found that this indirect exchange coupling between the neighboring Fe spins is ferromagnetic and maximized at the Fe-Fe distance of 2×2 superstructure.

In a prospective randomized trial, 318 children aged between 3 mo and 11 yr who were negative for all hepatitis B markers were randomized to receive two 5-μg doses of hepatitis B recombinant DNA yeast vaccine at 0 and 1 mo (group 1), three 5-μg doses of hepatitis B recombinant DNA yeast vaccine at 0, 1 and 6 mo (group 2) or three 10-μg doses of plasma-derived hepatitis B vaccine (group 3). The HBs antibody response rate at 8 mo was between 93% and 99%; it was still 75% to 87% at 5 yr in all three groups. Geometric mean titers at 1 yr were 83, 1,085 and 858 mIU/ml in groups 1, 2 and 3, respectively. These values had decreased after 5 yr to 47, 131 and 250 mIU/ml. Subjects in group 1 showed a significantly less proportional drop in geometric mean titer at the fifth year than did subjects in group 2 (p = 0.05) or group 3 (p = 0.015). None of the children developed HBc antibody, even after 5 yr of follow-up. We noted 42 episodes of significantly increased HBs antibody titers, probably due to anamnestic response, even when the titers had dropped to low levels. The mean age at which anamnestic response occurred was 8.7 yr. We conclude that (a) the recombinant vaccine and plasma-derived vaccine are comparable in safety and immunogenicity; (b) two doses of vaccine was as effective in protecting hepatitis B infection as three doses, despite lower HBs antibody titers; (c) anamnestic responses occurred most frequently around 4 yr after a child began attending school; and (d) a booster dose was not necessary at 5 yr, probably because of ability of healthy child vaccinees to mount good anamnestic responses. (HEPATOLOGY 1993;18:763-767).

We report the observation of a strong temperature dependence of the Kondo resonance in the valence-band photoemission spectrum and of the 3d\ensuremath{\rightarrow}4f white line in the x-ray absorption spectrum of ${\mathrm{YbAl}}_{3}$. The asymmetric Kondo resonance has a binding energy of \ensuremath{\sim}35 meV with a \ensuremath{\sim}50 meV width. The temperature dependence of the Yb 4f spectral features and valence are well reproduced by Anderson impurity model calculations with a Kondo temperature of ${\mathit{T}}_{\mathit{K}}$\ensuremath{\approxeq}400 K, demonstrating that both spectroscopic and near ground state properties can be described within a unified theoretical framework.

To evaluate the clinical efficacy of interferon-alpha in hepatocellular carcinoma, 71 adult Chinese patients with histologically proven inoperable hepatocellular carcinoma were randomized to receive recombinant interferon-alpha 2a (50 x 10(6) IU/m2) intramuscularly three times a week (n = 35) or no antitumor therapy (n = 36). The survival of interferon-alpha-treated patients was significantly better than that of patients who received no antitumor therapy (p = 0.0471); median lengths of survival were 14.5 and 7.5 wk, respectively. Objective tumor regression greater than 50% was observed in 31.4% (11 of 35) of patients receiving interferon-alpha. Interferon-alpha induced tumor regression greater than 50% in 11 (31.4%) patients. Compared with the group receiving no antitumor therapy, the interferon-alpha therapy group had more tumor regression (p < 0.0001) and less tumor progression (p = 0.001). This high-dose interferon-alpha therapy was relatively well tolerated; only 34.3% of patients required reduction of dosage by one third or one half because of persistent fatigue. Two patients with diabetes mellitus (one also had tabes dorsalis) exhibited mental deterioration that might have been partially attributable to interferon-alpha therapy. We conclude that interferon-alpha is useful in a proportion of Chinese patients with inoperable hepatocellular carcinoma, both in prolonging survival and in inducing tumor regression.

The impact behavior of composite sandwich panels subjected to a cylindrical impactor is investigated numerically and experimentally. Three kinds of facesheets and two different core densities of sandwich panels are considered in the impact analysis. During the experiment, the impact force and strain history are measured, and the failure is inspected by visual observations. The experimental results show that the impact behavior is mainly controlled by core material. The ABAQUS finite element software is used to analyze the impact responses of sandwich panels. Because of line load conditions, the sandwich panels impacted by the cylindrical impactor is modeled as a 2-D plane strain problem. The numerical results of impact force and strain history are compared with those measured in experiment, it is shown that the experimental results are in good agreement with the finite element solutions. Further, the stresses of sandwich panels are examined. The maximum stress failure criterion is used to estimate the fracture initiation of sandwich panels. Then the experimental and numerical results are compared and discussed.

X-ray absorption spectroscopy has been used to investigate the electronic structure of as-deposited and oxidized Ni/Au contacts on p-GaN. The Ni K-, L2,3-, and O K-edges x-ray absorption spectra clearly show the formation of NiO in the annealed contacts. Annealing in air increases Ni-site hole concentration and slightly shortens the nearest-neighbor Ni–O bond length, which enhances p–d hybridization and charge transfer from Ni to O. The observed very low specific contact resistance in the oxidized contacts is found to be due to the enhanced hole concentration at the Ni site.

Agricultural activity is the dominant factor affecting water quality and nitrate export, which causes eutrophication and episodic acidification in downstream water bodies (e.g., reservoirs, lakes, and coastal zones). However, in subtropical mountainous areas such environmental impact due to the land use change was rarely documented. In this study, we investigated 16 sub-catchments during 2007 and 2008 in the Chi-Chia-Wan catchment where is the sole habitat for the endemic species, Formosan landlocked salmon (Oncorhynchus masou formosanus). The results revealed that the NO3-N concentration in pristine catchments varied from 0.144 to 0.151 mg/L without significant seasonal variation. This concentration was comparable with other forestry catchments around the world. However, the annual nitrate export was around 375.3–677.1 kg/km2/yr, much higher than other catchments due to the greater amount of rainfall. This is an important baseline for comparisons with other climate areas. As for the impact of agricultural activities, the catchments with some human disturbance, ~5.2% of the catchment area, might yield 5947.2 kg N/km2/yr – over 10-times higher than that of pristine catchment. Such high export caused by such a low level of disturbance might indicate that subtropical mountainous area is highly sensitive to agricultural activities. As for the land-use effect on nitrate yield, the forestry land might yield 488.5 ± 325.1 kg/km2/yr and the vegetable farm could yield 298 465.4 ± 3347.2 kg/km2/yr – 1000-times greater than the forestry. The estimated nitrate yields for land use classes were a crucial basis and useful for the land manager to assess the possible impacts (e.g., non-point source pollution evaluation and the recovery of land expropriation).