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Background: Little is known about medical students’ perceptions of which criteria are important in residency selection. Student knowledge of this process may affect their education and their ability to obtain the residency of their choice. Objective: To determine the perceived importance among medical students of various selection criteria for residency. Design, Setting and Participants: Medical students at three institutions were asked to rate the importance of various residency selection criteria using a web-based survey instrument. Main Outcome Measures: Sixteen residency selection criteria were included in the survey. Results: The overall response rate was 49.2%. Criteria perceived as extremely important by the majority of students were the interview (80.6%), grades in third and fourth year courses in their chosen specialty (73.3%), letters of recommendation excluding the Dean’s letter (65.3%), and grades in third and fourth year clerkships (55.9%). USMLE Step 1 score (46.7%) was viewed as extremely important by many students. Moderately important: grades in fourth year electives not in their chosen specialty (57.3%), medical school’s reputation (50.5%), number of honor grades (49.0%), USMLE Step 2 score (42.3%), and Dean’s letter (41.1%). Mildly/not important: grades in the first and second years (56.8%), academic awards (55.2%), extracurricular activities (52.6%), research (50.9%), class rank (49.3%), and AOA (46.5%). Students in the clinical years of training were more likely to place importance on honors grades (p=0.04) and AOA (p=0.009) and were less likely to place importance on grades in fourth year electives not in their chosen specialty (p

Tm3+ and Dy3+ co-doped zinc-aluminum phosphate glasses were prepared in this study. Judd-Ofelt theory has been used to evaluate the three intensity parameters Ω2, Ω4 and Ω6 form the experimental oscillator strengths. The luminescence properties were investigated by excitation and emission spectra. White light emission could be induced by combined blue and yellow bands under UV excitation, and the variety of excitation wavelength could change the luminescence color.

We report on the growth of high quality single crystals of CuxBi2Se3 with x=0, 0.12 and 0.15, using Bridgman method. A study of crystal structure shows that the c -lattice parameter slightly decreases with an increasing level of Cu-doping. STM images indicate that both Cu-intercalation between Se-Se layers and Cu-substitution in Bi-layer sites are present. With dc magnetization measurements, superconducting transitions in Cu-intercalated Bi2Se3 have been found with a TC of 3.5 K for x∼0.12 and approximately 3.6 K for x∼0.15, respectively. The resistivity data show metallic behavior in the Bi2Se3 crystals and paramagnetic features are observed in the low temperature region of the Cu-doped samples.

Miniemulsion copolymerizations of styrene (ST) and stearyl methacrylate (SMA) or lauryl methacrylate (LMA) were investigated. Miniemulsions comprising ST and various levels of SMA showed very good storage stability against the diffusional degradation of monomer droplets (Ostwald ripening), whereas miniemulsions comprising ST and various levels of LMA exhibited significant Ostwald ripening. In subsequent miniemulsion copolymerizations of ST and SMA, particle nucleation occurring in the continuous aqueous phase (homogeneous nucleation) plays an important role in the particle formation process in addition to monomer droplet nucleation. The final overall conversion and the individual conversions of ST and SMA all decrease with increasing SMA concentration. Furthermore, at a particular reaction time, the individual conversion of SMA is always greater than that of ST. Monomer droplet nucleation was retarded severely for the monomer pair ST/LMA, presumably due to the very strong Ostwald ripening effect. As a result, relatively slow rates of copolymerization of ST and LMA were attained compared with the ST/SMA counterpart. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Tri-block nonionic surfactant and titanium chloride were used as starting materials for the synthesis of mesoporous titania nanocrystallite powders. The main objective of the present study was to examine the synthesis of mesoporous titania nanocrystals and the adsorption of vitamin E on those nanocrystals using X-ray diffraction (XRD), transmission electron microscopy, and nitrogen adsorption and desorption isotherms. When the calcination temperature was increased to 300 {sup o}C, the reflection peaks in the XRD pattern indicated the presence of an anatase phase. The crystallinity of the nanocrystallites increased from 80% to 98.6% with increasing calcination temperature from 465 {sup o}C to 500 {sup o}C. The N{sub 2} adsorption data and XRD data taken after vitamin E adsorption revealed that the vitamin E molecules were adsorbed in the mesopores of the titania nanocrystals.

The purpose of this paper presents the optical properties of microstructure of lightguiding plate for micro injection molding (MIM) and micro injection-compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of microstructure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate uses the PMMA plastic. This paper uses the luminance distribution to make a comparison between MIM and MICM for the optical properties of lightguiding plate. The important parameters of process for optical properties are the mold temperature, melt temperature and packing pressure in micro injection molding. The important parameters of process for optical properties are the compression distance, mold temperature and compression speed in micro injection-compression molding. The process of micro injection-compression molding is better than micro injection molding for optical properties.

Two muscular relaxants (MR), methyl ethers of N -benzoyl tyramine (Riparin I) and N -(1,6-dihydroxybenzoyl) tyramine (Riparin III) were studied with X-ray diffraction (XRD), optical spectroscopy and semi-empirical calculations. The XRD data show that the C O group in Riparin I is 34° out of plane from the closest benzene ring. The abinitio calculations using RHF/6-31G* suggest that the dihydroxybenzoyl (DHB) group in Riparin III forms intramolecular hydrogen bond between the H of the O–H group and the O of the C O group, and gives a relatively planar structure between DHB group and C O group. The spectral analysis together with the excitation energy calculations using the ZINDO program showed that the absorption band at 309 nm in Riparin III, absence in Riparin I, is assigned to the π→π* transition associated mainly from the DHB. A long range charge-transfer (CT) transition, as the low-lying excited electronic state, S 1 has been calculated for both relaxants involving the non-bonding electron on carbonyl and/or amine group and the antibonding orbitals of aromatic ring. The planar structure of Riparin III and its extensive electron delocalization may have an important role on the pharmacological action mode and on the potency this MR as compared to those of Riparin I.

An optically transparent xerogel encapsulating Cu(II) acetate is fabricated to detect mustard gas (HD) analogues via a charge-transfer mechanism. A fast response (color change from sky blue to canary yellow) is observed for the chlorinated sulfide, and is accompanied by an absorption band at 370–420 nm. MO calculations revealed that the chlorinated HD analogue displays a charge-transfer transition extended from sulfur to chlorine atom. A 1:1 complex of Cu(II)/HD analogue is preferred. For a colorimetric sol–gel detector prepared at pH 3, the detection limit of HD analogue is calibrated at 0.03 μl per 1.5 ml sensor volume.

A building safety management system based on image processing technology, which includes the license plate recognition, face recognition, and Radio Frequency Identification(RFID) systems are investigated in this paper. The system integrates three functional capabilities, which can effectively control access to user identity and to control management building security. The image technology is used to do license plate and facerecognition. In order to recognize the license plate and face thecolor space conversion, segmentation, and image processing technology is applied. Finally, the integration of RFID image processing is applied to automatic security management system. Only the identified users can pass through the gate of building to make sure the security. Keywords-image processing technology; license plate recognition; face recognition; radio frequency identification

Previous research has shown that nitrogen from municipal wastewater could be eliminated by a biofilter system. In this study a system of combined pre-denitrification/nitrification biofilters was set up. It is to investigate the effect of the hydraulic loading and recycled ratio on nitrogen removal. The characteristics of bacterial activity at different heights is discussed. The experiment shows that longer hydraulic loading would result in better total nitrogen removal. Total nitrogen removal might be not dependent on denitrification but nitrification. Hydraulic loading that affects nitrification might be due to the diffusion of NH3–N from the bulk solution to the inner biofilm. The recycling NO3–N could be completely eliminated in the anoxic biofilter. The operation with longer retention time (HRT of 12 hours) would result in inner denitrification in the aerobic biofilter. Biological activity could be determined by the distribution of bacteria. The specific rates of pollutant decomposition depend on biological activity and effective biological VSS. The effect of the recycled ratio on the nitrogen removal is significant. Total nitrogen removal rate and nitrogen type of effluent would be determined by recycle ratio. The operation at low recycled ratio would result in worse total nitrogen removal, but the NH3–N of effluent would be lower. The operation in higher recycle ratio would be opposite to low recycle ratio.

Proposes an easy and reproducible vapor-phase photo surface treatment method to improve the device performance of the Hg/sub 0.8/Cd/sub 0.2/Te photoconductive detector. We explore the effect of surface passivation on the electrical and optical properties of the HgCdTe photoconductor. Experimental results, including surface mobility, surface carrier concentration, metal-insulator-semiconductor leakage current, 1/f noise voltage spectrum, the 1/f knee frequency, responsivity R/sub /spl lambda//, and specific detectivity D* for stacked photo surface treatment and ZnS or CdTe passivation layers are presented. These data are all directly related to the quality of the interface between the passivation layer and the HgCdTe substrate. We found that, by inserting a photo native oxide layer, we can shift the 1/f knee frequency, reduce the noise power spectrum, and achieve a lower surface recombination velocity S. A higher D* can also be achieved. It was also found that HgCdTe photoconductors passivated with stacked layers show improved interface properties compared to the photoconductors passivated only with a single ZnS or CdTe layer.

Formation of silicided shallow n + p junctions by phosphorus implantation into thin poly-Si films on Si substrates and subsequent Co silicidation has been studied. As for the non-silicided samples, good n + p junctions can be formed only at an annealing temperature as high as 900°C. On the other hand, as for the silicided samples processed at 800° C, a Co-silicided n + p junction with a leakage of about 2 nA/cm 2 at −5 V and a depth of about 0.07 μ m can be obtained. The resulting junctions are significantly improved with increasing Co film thickness due to silicidation-enhanced dopant drive-in. However, as for the samples processed at 900°C, the Co silicidation using different Co film thickness yields the same junction characteristics due to sufficiently high dopant drive-in efficiency. Moreover, for the samples implanted at a relatively high energy, the junctions formed using a thicker Co film may be degraded by silicidation due to defect-enhanced Co penetration into the junction region.

Formation of Pd-silicided shallow n + p junctions by implanting P + ions into thin Pd or Pd 2 Si films on a Si substrate and subsequent annealing has been studied. Using these schemes, good n + p junctions can be formed at low annealing temperatures. A Pd 2 Si-silicided shallow n + p junction with a leakage of about 2 nA/cm 2 at −5 V and a junction depth of about 0.1 μm can be obtained by annealing the sample with P + implantation into thin Pd 2 Si films at 700°C. The thermal stability and silicide crystallinity of thin Pd 2 Si films on Si can be significantly improved due to the implanted phosphorus dopant, as compared to the control samples without dopant incorporation.

The crystal structure (rhombohedral) is not changed on the replacement of Mn by Co. The lattice parameters a and c decrease with the increasing Co concentration. In this paper we have systematically investigated the effect of Co doping on the Mn site in the La0.7Sr0.3MnO3 and find that Co substitution leads to a drastic suppression of ferromagnetic long-range order and metallic state. However, we observed substantial enhancement of MR ratio over the entire temperature studied for x=0.1 and a large increase of one at the low temperature for the compositions of x=0.2 and 0.3. The largest MR ratio as high as ≈78% is observed at 15 K in x=0.2 and 0.3. As x is further increased toward 1, conduction and ferromagnetism strongly recover but the MR ratio decreases obviously. The end member with x=1.0 has metallic and cluster spin-glass ferromagnetic behavior (T

The influence of body temperature on focal cerebral ischaemia-reperfusion was investigated by using a well established rat stroke model. Three different degrees of ischaemia were created in the cerebral cortex of the right middle cerebral artery territory by varying the duration of clamping of the bilateral common carotid arteries and the right middle cerebral artery with full reperfusion. Mild hyperthermic (body temperature 38-39 degrees C) influence during ischaemia significantly enhanced the severity of infarction in mild (30 min) ischaemia, mean infarct volume was 78% greater than normothermic (body temperature 36.5-37.5 degrees C) group (P < 0.001); and in moderate (60 min) ischaemia, mean infarct volume was 23% greater than in the normothermic group (P < 0.05); but no difference between the two groups was observed in severe (90 min) ischaemia. Our data suggest that mild whole body hyperthermia during focal ischaemia-reperfusion has a detrimental effect on the infarct volume only in mild and moderate ischaemia in this model.

The fatigue crack growth in Fiber Reinforced Aluminum Laminates (FRALL) involves two inter-related damage processes, i.e. crack growth within the aluminum layer and delamination growth between the aluminum layer and the composite core. In this study, the fatigue crack growth behavior in Carbon fiber Reinforced Aluminum Laminates (CARALL) was analyzed using a simplified model which takes both fiber bridging effects and the delamination propagation into account, supplemented by an iterative calculation scheme. Results indicated that the delamination growth during the fatigue process exhibits an effective self-adjusting property such that the size of the delamination zone would converge rapidly, irrespective of the initial size. This is explained in terms of the decrease in the fiber bridging force, the driving force for delamination, as the delamination size increases. In general, however, the effect of delamination growth on the fatigue crack growth in CARALL was shown to be of secondary significance as compared to that of the stiffness of the composite core. It was argued that qualitative conclusions should be applicable to FRALL in general.

YBa2Cu3O7−δ (YBCO) thin films were deposited on n-type (100) silicon wafers with yttria-stabilized zirconia (YSZ) buffer layers by a laser ablation technique. The YSZ layer had a thickness of about 60 nm, and was oriented preferentially in the (100) direction. The YBCO films were found to be preferentially (001) oriented, and had a superconducting critical temperature (Tc) above 85 K. Pure gold ohmic contacts were made on both sides of the YBCO/YSZ/Si structure and its I-V characteristics revealed a diode behavior. The turn-on and breakdown voltages are 1.3 and 20.34 V, respectively, at temperatures below the Tc. The ideality factor η had values of 13, 9.5 and 7 at room temperature, 100 and 50 K, respectively. Better superconductivity, lower operation temperature, and thinner buffer layers would result in better rectification.

An experimental study was conducted to examine the fatigue delamination growth in carbon fibre-reinforced aluminium laminates (CARALL) under cyclic loading. The growth rate of cyclic delamination between the aluminium sheets and the fibre/epoxy composite core could be related to the effective strain energy release rate (Gmax - Gth) by a Paris type equation, dDdN = c(Gmax - Gth)m, where c and m are fitting constants. The threshold energy release rate Gth could be separated into two terms, Gth0 and Gr. It was shown that Gr could be related to the strain energy release rate solely due to thermal residual stresses in the laminate, while Gth0 might represent a parameter related to the intrinsic interfacial characteristics. Interestingly, the three constants c, m and Gth0 were found to be independent of the volume fraction of carbon/epoxy and the magnitude of thermal residual stress. Therefore, once the constants c, m and Gth0 were determined, the fatigue delamination growth in the hybrid laminate with various carbon/epoxy contents and/or thermal residual stresses could be predicted readily by this empirical equation.

A superior crack propagation resistance was observed on various carbon fiber-reinforced aluminum laminates (CARALL) under tension-tension fatigue. It might be attributed to the restraint on the crack opening imposed by intact fibers in the crack wake. These fibers bridging the crack could reduce the effective stress intensity factor actually experienced by the crack tip. Based on the measurement of crack length and delamination size, the effective stress intensity range, ΔKeff, of fatigue-damaged CARALL laminate was calculated by using a simplified analytical model. It was shown that the fatigue crack propagation rate in CARALL could be expressed as a unique function of the calculated ΔKeff, which agree well with the Paris equation for the unreinforced aluminum alloy. This result confirmed the applicability of this simplified analytical model in CARALL laminates.

Single crystal samples of BSCCO were cleaved in ultrahigh vacuum and studied using XPS with a monochromated Al Kα source. The resolution of the instrument is ~0.35 eV which is better than most previous XPS studies of BSCCO. We confirm that the shape of the Cu 2p and O 1s peaks imply multiple states. The samples were heated in situ to drive off O, to study how screening is affected by changes in stoichiometry. Auger parameters were used for this study. The Auger parameters of Bi, Ca, O, and Cu were estimated.

The effectiveness of acupuncture in acute stroke remains largely untested and unproved. A randomized, controlled trial was carried out to study the feasibility of acupuncture in combination with conventional supportive treatment for acute stroke patients. A total of 30 patients, aged 46-74, with the onset of symptoms within 36 h were enrolled into the study after appropriate screening. All patients gave informed consent. Basing on the same supportive treatment, patients were randomly assigned to a treatment with or without acupuncture. The procedure and acupoint selection were discussed and decided through several meetings of a group of senior acupuncture doctors in Taiwan. Acupuncture was applied 3 times/week for 4 weeks. During the study period, there were no problems in conducting this trial in terms of patient availability and acceptance, and physician cooperation. A significantly better neurologic outcome was observed in the acupuncture group on day 28 and day 90. The improvement in neurologic status was greatest in patients with a poor neurologic score at baseline. There were no important side effects except for one episode of dizziness related to acupuncture treatment. The data and results of this study will be used as a guideline for planning a full-scale clinical trial, e.g. sample size calculation, method of randomization with stratification of prognostic factors, choosing acupuncture points and technique of acupuncture.

The paper reports the impact of TiN metal gate composition (Ti-rich vs. N-rich) and preparation methodology (atomic layer deposition -ALD vs. physical vapor deposition -PVD) on its thermal stability with HfO 2 high-K dielectric, via both physical characterization (X-ray Photoelectron Spectroscopy -XPS, High Resolution TEM combined with Electron Energy Loss Spectroscopy -EELS), and electrical characterization (capacitance voltage -CV & current voltage -IV measurement). After annealing at 1000°C for 30s, it is observed that: 1) Nitrogen tends to out-diffuse from both PVD and ALD TiN; 2) Oxygen from the interfacial layer (IL) between HfO 2 and Si tends to diffuse towards TiN for all the samples. PVD Ti-rich TiN can scavenge more oxygen from IL, but also shows signal of Ti penetration into HfO 2 , which poses a concern on its thermal stability; 3) The oxygen out-diffusion from HfO 2 /IL stack can be significantly suppressed for ALD TiN compared to the PVD TiN, which is critical to maintain the HfO 2 integrity. The effective work function of TiN metal gate is correlated with its thermal stability.

Emission spectra of rhodamine 6G (R6G) aggregates were observed at 77 K both in water and in alcohols. The temperature behavior of emission and excitation spectra, and their excited state lifetimes illustrated that the transition moment of the lower exciton component, μ, for rhodamine 6G aggregates in alcohols is greater than that in water, but the nonradiative rate, rNR (in alcohol) ⪢ rNR (in water). Cyclic voltammetry analysis revealed that the structural disposition of R6G aggregates in water tends to decrease the pKa of the quaternary amine group in rhodamine 6G, which then promotes large changes of current—voltage signal in the reduction of free H+ and oxidation of its counterion, Cl−.

Two SMSD gate first planar CMOS devices were demonstrated. Vtn/Vtp= +0.49V/−0.48V were achieved by adjusting TiN to p-like metal and As I/I on nMOS. This enables the equivalent +/−0.2V low Vt target of N22 fully depleted CMOS technologies. Vtn/Vtp= 0.52/− 0.55 were obtained by transforming PVD-TiN/Ti into n-like metal TiN/TiSix for nMOS and by Al I/I on TiN/Ti for pMOS. Al diffusion was facilitated by snowplow effect of TiSix formation on pMOS. As low as 7.3A EOT with decent Jg 6.4E-3 A/cm2 @1.1Vwas obtained.

A new hybrid composite (CARALL), consisting of thin layers of carbon fibre/ epoxy prepreg sandwiched between aluminium sheets, has been developed. It is shown that this class of materials offers higher modulus, higher tensile strength and lower density than 2024-T3 alloy in the longitudinal direction. Under tension-tension fatigue loading, the hybrid laminates showed superior fatigue crack propagation resistance in the longitudinal direction, which may be attributed to the bridging effect imposed by the intact fibres in the crack wake. It has also been shown that the effectiveness of fatigue crack growth reduction increases with the thickness of the carbon fibre/epoxy layer. The resistance to fatigue crack propagation can be further improved by introducing compressive residual stresses in the aluminium layer by postcure stretching the laminate in the plastic region of the aluminium alloy.

Integration of high-k/metal gate stacks has been discussed in this paper. Pre-gate clean, interfacial oxide treatment, high-k and metal film deposition were investigated for optimized Jg-EOT. Various approaches such as HF vapor clean, surface hydroxylation treatment, and metal gate modification (such as interface treatment and high density top layer) were employed to improve the electrical properties. Electrical characterization (C-V, I-V) and material analysis (TEM, XPS) were conducted to examine the effects of these approaches on high-k/metal gate stacks.

Emission and excitation spectra of undoped lead lanthanum zirconate titanate (PLZT) and chromium-, iron-, neodymium- and praseodymium-doped samples were recorded at 77 K. The spectral characteristics were analyzed with respect to the effects of the doping atmosphere, types of dopant and dopant concentration. Undoped PLZT ceramic has a visible absorption resulting from an iron impurity. Upon doping with chemically active ions, an increase in the visible light absorptivity is revealed in the excitation spectrum. A large photocurrent is detected at 400–500 nm, correlating with the chemically active iron ions.

The experience of using a database management system (DBMS) to handle the large amounts of data involved in distribution system reliability evaluation is reported. To demonstrate the capability of the DBMS in data manipulation, reliability evaluation of a distribution system in Taiwan is performed using a DBMS installed on an IBM PC/AT. It is found that using the DBMS tool is a very efficient way of organizing data required by distribution planners. Moreover, the DMBS method is very cost-effective, since it is installed on a personal computer. >

This study utilizes a real options approach to construct a mathematical decision-making model of multistage acquisitions so as to achieve an optimal strategy for the stages of negotiating, acquiring and exiting. This work assesses either waiting to acquire value and/or potential exit value or true value at each stage and provides to search a stable equilibrium solution which is recognized by acquiring and acquired firms. This investigation also considers the bidding strategy in the stage of negotiating. Furthermore, the proposed model of acquiring price which is decided by a mix-strategy for running the equilibrium expected firm value is also a main focus in this study.

A highly scaled, high performance 45 nm CMOS technology utilizing extensive immersion lithography to achieve the industry's highest scaling factor with ELK (k=2.55) BEOL is presented. A record gate density 2.4X higher than that of 65 nm is achieved. Refined strained-CMOS demonstrated 1200/750 μA/μm Idsat at 100 nA/μm Ioff, Vdd=1 V, which has the best Ion-Lg performance reported for bulk CMOS device. The proposed 45 nm technology is not only manufacturing friendly but also has well-controlled leakage and mismatch evidenced by a functional 32 Mb 0.242 μm2 SRAM.

FUSI metal gate with strained engineering is extensively investigated and reported for the first time. Enveloped FUSI (fully silicided) phase transfer and volume change induced stress exhibits 10% NMOS ION enhancement. Further, the second CESL (contact etch stop layer) induced stress raised another 8% NMOS ION gain. Although the first CESL on poly-gate top removed by FUSI CMP leads to 10% PMOS ION degradation, it can be recovered or further improved by a dual CESL process

Experimental results are presented for noise voltage, responsivity, and specific detectivity (D*) for the long wavelength infrared (IR) HgCdTe photoconductive detectors. Hg/sub 0.8/Cd/sub 0.2/Te photoconductive detectors passivated with ZnS/photo-enhanced native oxide have an improved noise spectral density and D* than the detectors passivated with only ZnS. The low frequency 1/f noise charges were measured for a Hg/sub 0.8/Cd/sub 0.2/Te photo detector, as a function of bias at 77 K, and the effective surface trap density determined from the 1/f noise charges measured at 1 Hz. It was found that the surface effective trap densities of stacked passivated sample and the sample passivated only with ZnS are close to 4/spl times/10/sup 17/ and 9/spl times/10/sup 17/ cm/sup -2/ eV/sup -1/ under 0.4 V bias and 1 /spl mu/s integration time, respectively. We found that the numerical values of noise are strongly dependent upon surface passivation properties. It can be seen clearly that an HgCdTe photo detector with a stacked ZnS/photo-enhanced native oxide passivation is better than the HgCdTe photo detector passivated with a single ZnS layer.

We report for the first time PMOS drive current enhancement with in-situ boron doped SiGe incorporation in recessed S/D regions for devices built on thin body SOI substrate. For P-channel PD-SOI devices with 450 A silicon on insulator and 38nm gate length, 35% linear drain current enhancement and 20% saturation drain current improvement have been achieved with this approach. Device integration and performance improvement are discussed below.

This paper presents a 65 nm CMOS technology that achieves a logic density of 900 k-gates/mm/sup 2/ and a SRAM memory density of 1.4 Mb/mm/sup 2/ using a sub-0.49 /spl mu/m/sup 2/ bitcell. Key features of a low cost technology option for mobile products (MP) and a high performance technology option (HP) for DSP based applications are described.