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A kind of n–p (SnO2)1.3/(α ∼ Bi2O3)x/(β ∼ Bi2O3)1−x nanocomposite (SB-15) was synthesized with polyvinyl alcohol (PVA) as a template by solid state synthesis. XRD and HR-TEM confirmed the formation of n–p (SnO2)1.3/(α ∼ Bi2O3)x/(β ∼ Bi2O3)1−x. Particle size is found to be about 18 nm from HR-TEM images. FE-SEM clearly detected the boundary between SnO2 nanoparticles and Bi2O3 polyhedron particles. The special morphology and coexisting of α-Bi2O3 and β-Bi2O3 in SB-15 make it have a stronger visible light absorption range as far as 725 nm. PL and photocurrent test shows that the SB-15 has the best photocarriers separation capability. About 99% decolorization ratio of Rh.B was achieved in only 5 min. About 70% Cr6+ was degraded within 20 min and it is about 60% for tetracycline in the coexisting system (Te with Cr6+ solution), introducing it as a promising photocatalytic material. This work has addressed the method of phase-selective synthesis of n–p SnO2/α ∼ Bi2O3/β ∼ Bi2O3 by convenient solid state synthesis, which should be useful for the studies of other composites.
OBJECTIVES/SPECIFIC AIMS: Patients with locally advanced pancreatic cancer typically have poor outcomes, with a median survival of ~16 months. Novel methods to improve local control are needed. Nab-paclitaxel (abraxane) has shown efficacy in pancreatic cancer and is FDA approved for metastatic disease in combination with gemcitabine. Nab-paclitaxel is also a promising radiosensitizer based on laboratory studies, but it has never been clinically tested with definitive radiotherapy for locally advanced disease. METHODS/STUDY POPULATION: We performed a phase 1 study using a 3+3 dose-escalation strategy to determine the safety and tolerability of dose escalated nab-paclitaxel with fractionated radiotherapy for patients with unresectable or borderline resectable pancreatic cancer. Following induction chemotherapy with 2 cycles of nab-paclitaxel and gemcitabine, patients were treated with weekly nab-paclitaxel and daily radiotherapy to a dose of 52.5 Gy in 25 fractions. Final dose-limiting toxicity (DLT) determination was performed at day 65 after the start of radiotherapy. RESULTS/ANTICIPATED RESULTS: Nine patients received nab-paclitaxel at a dose level of either 100 mg/m2 (n=3) or 125 mg/m2 (n=6). One DLT (grade 3 neuropathy) was observed in a patient who received 125 mg/m2 of nab-paclitaxel. Other grade 3 toxicities included fatigue (11%), anemia (11%), and neutropenia (11%). No grade 4 toxicities were observed. With a median follow-up of 8 months (range 5–28 months), median survival was 19 months and median progression-free survival was 10 months. Following chemoradiation, 3 patients underwent surgical resection, all with negative margins and limited tumor viability. Of the 3 patients, 2 initially had borderline resectable tumors and 1 had an unresectable tumor. Tumor (SMAD-4, Caveolin-1) and peripheral (circulating tumor cells and microvesicles) biomarkers were collected and are being analyzed. DISCUSSION/SIGNIFICANCE OF IMPACT: The combination of fractionated radiation and weekly nab-paclitaxel was safe and well tolerated. This regimen represents a potentially promising therapy for patients with unresectable and borderline resectable pancreatic cancer and warrants further investigation.
Previous studies have indicated that there is dopamine transporter (DAT) dysregulation and P300 abnormality in adults with attention-deficit hyperactivity disorder (ADHD); however, the correlations among the three have not been fully explored.
A total of 11 adults (9 males and 2 females) with ADHD and 11 age-, sex-, and education-level-matched controls were recruited. We explored differences in DAT availability using single-photon emission computed tomography and P300 wave of event-related potentials between the two groups. The correlation between DAT availability and P300 performance was also examined.
DAT availability in the basal ganglia, caudate nucleus, and putamen was significantly lower in the ADHD group. Adults with ADHD had lower auditory P300 amplitudes at the Pz and Cz sites, as well as longer Fz latency than controls. DAT availability was negatively correlated to P300 latency at Pz and Fz.
Adults with ADHD had both abnormal DAT availability and P300 amplitude, suggesting that ADHD is linked to dysfunction of the central dopaminergic system and poor cognitive processes related to response selection and execution.
We aimed to clarify whether invasive dental treatment is associated with increased risk of prosthetic joint infection (PJI) and whether prophylactic antibiotics may lower the infection risk remain unclear.
Retrospective cohort study.
All Taiwanese residents (N=255,568) who underwent total knee or hip arthroplasty between January 1, 1997, and November 30, 2009, were screened.
The dental cohort consisted of 57,066 patients who received dental treatment and were individually matched 1:1 with the nondental cohort by age, sex, propensity score, and index date. The dental cohort was further divided by the use or nonuse of prophylactic antibiotics. The antibiotic and nonantibiotic subcohorts comprised 6,513 matched pairs.
PJI occurred in 328 patients (0.57%) in the dental subcohort and 348 patients (0.61%) in the nondental subcohort, with no between-cohort difference in the 1-year cumulative incidence (0.6% in both, P=.3). Multivariate-adjusted Cox regression revealed no association between dental procedures and PJI. Furthermore, PJI occurred in 13 patients (0.2%) in the antibiotic subcohort and 12 patients (0.18%) in the nonantibiotic subcohorts (P=.8). Multivariate-adjusted analyses confirmed that there was no association between the incidence of PJI and prophylactic antibiotics.
The risk of PJI is not increased following dental procedure in patients with hip or knee replacement and is unaffected by antibiotic prophylaxis.
The spiritual well-being of terminally ill cancer patients is an important indicator of the quality of their lives and of the quality of hospice care, but no validated tools are available for assessing this indicator in Taiwan.
The present cross-sectional study validated the Spiritual Well-Being Scale–Mandarin version (SWBS–M) by testing its psychometric properties in 243 cancer patients from five teaching hospitals throughout Taiwan. Construct validity was tested by factor analysis and hypothesis testing. Patients' spiritual well-being and quality of life were assessed using the SWBS–M and the McGill Quality of Life Questionnaire (MQoL), respectively.
Overall, the SWBS–M had an internal consistency/reliability of 0.89. Exploratory factor analysis showed that the SWBS–M had an underlying two-factor structure, explaining 46.94% of the variance. SWBS–M scores correlated moderately with MQoL scores (r = 0.48, p < 0.01). Terminally ill cancer patients' spiritual well-being was inversely related to their average pain level during the previous 24 hours (r = –0.183, p = 0.006). Cancer patients' spiritual well-being also differed significantly with their experience of pain (t = –3.67, p < 0.001); terminally ill cancer patients with pain during the previous 24 hours had a lower sense of spiritual well-being than those without pain.
Significance of results:
Our findings support a two-factor model for the SWBS–M in terminally ill Taiwanese cancer patients. We recommend testing the psychometric properties of the SWBS–M in different patient populations to verify its factorial structure in other Asian countries.
The mean radial velocity of NGC 288 (accuracy 5.5 km/s) is determined to be −56.3 ± 20.1 km/s which, when combined with the mean proper motion (Guo, 1995), yields a peculiar velocity with respect to the LSR of (u,v,w) = (29.7 ± 18.1, −258.6 ± 18.3,62.3 ± 20.3) km/s. This implies that NGC 288 moves in a retrograde sense with the Galactic rotation. We also derived the effective temperatures for stars in our sample and, as a corroborative effort, compared with those estimated previously from the BATC data (Tsai 1998) by spectral energy distribution fitting. We demonstrate that the BATC/SED fitting is an appropriate and efficient way to estimate the effective temperature of a star.
The boundary element method (BEM) is easier than the finite element method (FEM) on the viewpoint of the discretization of one dimension reduction rather than the domain discretization of finite element method. The disadvantage of BEM is the rank deficiency in the influence matrix, e.g., degenerate boundary, degenerate scale, spurious eigenvalues and fictitious frequencies, which do not occur in the FEM. The conventional BEM can not be straightforward applied to solve a problem which contains a degenerate boundary without decomposing the domain to multi-regions. A hypersingular integral equation is used to ensure a unique solution for the problem containing a degenerate boundary. By combining the singular and hypersingular equations, it’s termed the dual BEM due to its dual frame. Following the successful experience on the retrieval of information using the singular value decomposition (SVD) updating term and updating document, this technique is also used to extract out the degenerate-boundary information and the rigid-body information in the dual BEM. It is interesting to find that true information due to a rigid-body mode in physics is found in the right singular vector with respect to the corresponding zero singular value while the degenerate-boundary mode (geometry degeneracy) in mathematics is imbedded in the left singular vector with respect to the corresponding zero singular value. The role of the common right and left singular vectors of SVD for the four influence matrices in the dual BEM is also discussed in this paper. Two examples, a potential flow problem across a cutoff wall and a cracked bar under torsion were demonstrated to see the mathematical SVD structure of four influence matrices in the dual BEM.
Metal organic chemical vapor deposition, as well as material and basic device properties of nitride-based high electron mobility transistor structures on (111) silicon substrates varying in diameter from 4 to 8 inch were studied using in-situ and ex-situ characterization techniques. All substrates used for the growth of the nitride structures in this study were of SEMI standard thicknesses. The total thickness of the nitride structures was in the range of 1.5 – 5 µm. It is reported that nitride structures can be grown on 4, 6 and 8 inch diameter substrates with very similar post-growth wafer shape, material and device characteristics. It is also shown that their crystal quality, 2DEG transport properties and isolation blocking voltages can be improved by increasing nitride structure thickness while maintaining post-growth wafer bow and warp less than 50 µm. The maximum thickness of nitride structures that can be successfully grown on 8 inch diameter SEMI standard substrates seems to be limited to about 4.5 µm due to plastic deformation of Si. Blocking voltages of more than 700 V were achieved using 4.5 µm thick nitride-based high electron mobility transistor structures grown on 8 inch Si substrate.
A novel allergy biosensor is designed and fabricated by using thin film bulk acoustic resonator (TFBAR) devices with shear mode ZnO piezoelectric thin films. To fabricate TFBAR devices, the off-axis RF magnetron sputtering method for the growth of piezoelectric ZnO piezoelectric thin films is adopted. The influences of the relative distance and sputtering parameters are investigated. In this report, the piezoelectric ZnO thin films with tilting angle are set by controlling the deposition parameters. The properties of the shear mode ZnO thin films are investigated by X-ray diffraction and scanning electron microscopy. The frequency response is measured using an HP8720 network analyzer with a CASCADE probe station. The resonance frequency of the shear mode is 796.75 MHz. The sensitivity of the shear mode is calculated to be 462.5 kHz·cm2/ng.
This paper reports a novel means of integrating a high-performance dual-modal ZnO piezoelectric transducer with a flexible stainless steel substrate (SUS304) to construct dual-modal vibration-power transducers. To fabricate vibration-power transducers, the off-axis RF magnetron sputtering method for the growth of ZnO piezoelectric thin films is adopted. The stainless steel substrate has a higher Young’s modulus than those of the other substrates, and behaves the long-term stability under vibration. The transducer includes a ZnO piezoelectric thin film deposited on the stainless steel substrate combined with Pt/Ti layers at room temperature, which is fabricated by an RF magnetron two-step sputtering system. In this report, the ZnO piezoelectric thin films deposited with the tilting angle of 34° are set by controlling the deposition parameters. Scanning electron microscopy and X-ray diffraction of ZnO piezoelectric thin films reveal a rigid surface structure and a high dual-modal orientation. To investigate the generating characteristics of the dual-modal transducer, two basic experiments of longitudinal and shear modes are carried out. Based on cantilever vibration theory, the cantilever length of 1 cm and a vibration area of 1 cm2 are used to fabricate a transducer with a low resonant-frequency of 65 Hz for the natural vibration. A mass loading at the front-end of the cantilever is critical to increase the amplitude of vibration and the power generated by the piezoelectric transducer. The maximum open circuit voltage of the power transducer is 19.4 V.
This study investigated how cross-functional teams can influence their business model innovation and firm performance through team learning, consisting of multiple modes of within-team, cross-team, and market learning. Using a matched dyadic data set from a study of 330 cross-functional team members and their supervisors sampled from 165 electronics and information industries in China, the empirical results clearly indicate that within-team, cross-team, and market learning can improve business model innovation and firm performance. The results of the mediating model show how the business model innovation mediates the relationship between team learning and firm performance.
As critical dimensions decrease, key dimension-related dielectric etch challenges emerge, including via and trench uniformity and etch depth profile. The transition to ultra-low-k films such as BDIII (Black Diamond; k=2.55) dielectrics requires consideration of film sensitivity to compositional modification, polymer interactions at pores, and the effect of diffusion. Use of N2/O2 plasma at 60 ˚C to modify the M1 trench profile has been demonstrated to lower the RC delay by 14% as compared to traditional CO2 plasmas at 60˚C. Use of a DHF solution to clean the etching residue in the dual damascene structure results in >97% yield with a tight range of via chain resistance.
The deposition of amorphous InGaZnO4 (a-IGZO) semiconductor film, via a sputtering process, has been demonstrated in the literature. In this paper, we present a solution method as an alternative to obtain this semiconducting film. The dispersible IGZO colloids is formed first by co-precipitation of precursors, followed by hydrothermal treatment at 200°C for 1 hour and using CMC as the dispersion agent. The crystalline colloid would become amorphous when it was heated at above 250°C. The TFT structure was made by growing a dielectric silica layer using the CVD method, a metal layer using the sputtering method, and an active IGZO layer using the solution method. This device exhibits low operating voltage, the mobility is about 2cm2V−1s−1 and the Ion/Ioff ratio is 104. Further improvement in processing is needed.
CoSi2 epitaxial layers with thickness ranging from 24 nm to 170 nm have been grown onto porous Si substrates by molecular beam epitaxy. The X-ray rocking curves and transmission electron microscopy (TEM) are used to examine the strain relaxation and interface quality. Backscattering with channeling is used to characterize the crystallinity of the epilayers. The results show that it is necessary to grow a thin buffer Si layer in order to improve the interfacial sharpness and crystallinity of the epilayers; near perfect crystallinity is then obtained as the thickness of the CoSi2 films exceed 50 nm. TEM results reveal that both CoSi2/Si and CoSi2/porous-Si interfaces are flat and layer thickness is uniform. It is found by TEM that the dislocation density of CoSi2 grown on porous Si is much lower than that on single-crystal Si. For thin CoSi2 grown on porous Si, the TEM and strain measurement results imply that part of the film is pseudomorphic where no dislocations are observed. Average strains of CoSi2 films grown on porous Si substrates with thicknesses greater than 30 nm show a lower strains comparing to that on crystalline Si. This suggests that by using porous Si as substrates the stress energy in the epilayer can be accommodated by the Si buffer layer that bridged over the trenches of porous Si.
The properties of the interface states of MBE grown CoSi2/n-Si(111) intimate contacts has been investigated using forward bias capacitance measurement. The barrier height øbn for this structure is 0.66±0.01 V. It has been found that there is an interface state band located in 0.44–0.50 eV bfow the conduction band edge of Si. The density of states D it is about 4×1012 cm−2 eV−1, lower than those made by other methods. This intrface state band is in equilibrium with Si and the charge exchange occurs mainly with the electrons in the conduction band of Si. The electron capture cross section oa is about 3×10−15 cm2 . In addition, some discrete interface states were found at 0.53 eV, 0.51 eV and 0.47 eV below the conduction band edge of Si, respectively for several samples. The density of states D it ranges (1.5–3.5)×1010 cm−2 . They are probably caused by localized point defects formed during CoSi2 growth.
The thermal oxidation of silicon in dry oxygen is examined with three different thickness measurements: Ellipsometry, transmission electron microscopy and step-profile measurements. The oxidation kinetics follow a linear-parabolic relationship throughout the measured thickness range. Previous deviations from linear-parabolic behavior result from inaccurate ellipsometer measurements of film thickness for films thinner than 0.05 /zm.
Soft-x-ray magnetic circular dichroism (MCD) is the difference between the absorptivity or reflectivity of left and right circularly polarized soft-x-rays at the magnetically interesting L2,3- edges of 3d transition metals or the M4,5-edges of the 4f rare earth elements. Thanks to its large absorption cross-section and strong MCD effect, this technique has become a powerful new means for probing, in an element- and site-specific manner, the magnetic properties of ultra-thin films and multilayers. Soft-x-ray MCD experiments, recently conducted at the Dragon beamline, are utilized to demonstrate the recent progress in this technique and its applications in the research of magnetic thin films.
A significant source current generated by a carrier multiplication process is observed at large drain voltages in the subthreshold regime, along with simultaneous increase of the gate current and light emission signal. Provided no on-surface premature breakdown takes place, a bulk channel avalanche breakdown process is proposed as the dominant breakdown mechanism for a large range of gate-to-source dc voltages. This process in the GaN channel is responsible for the excess source and drain currents, light emission, and excess gate current beyond its normal value measured in a gate-to-drain diode configuration. The role of the gate bias in controlling the channel vs. the gate breakdown mechanisms is described.
A systematic investigation of high field prebreakdown and breakdown phenomena of AlGaN/GaN Heterojunction Field Effect Transistors (HFETs) is presented. The breakdown process was studied as a function of various parameters such as applied electric field, material layer structure, semiconductor surface conditions, ambient dielectric, and test conditions. Experimental evidence of a breakdown mechanism, distinct from the bulk/subsurface breakdown, namely on-surface breakdown or surface flashover is presented. A practical, unambiguous way of identifying device failure by surface flashover is proposed. Surface flashover between gate and drain contact edges is proposed as the main mechanism initiating premature breakdown in these devices leading to a significant reduction of their power capability.
In this paper, simple techniques were proposed to fabricate germanium nanocrystal capacitors by one-step thermal oxidation and/or rapid thermal annealing on polycrystalline-SiGe (poly-SiGe) deposited with a LPCVD (low pressure chemical vapor deposition) system. This thermal oxidation method can directly result in the top-control oxide layer via the oxidation of amorphous-Si film and the formation of Ge nanocrystals from the poly-SiGe film. Otherwise, the rapid thermal annealing method can be also used to form Ge nanocrystals as comparison.