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In this study, we demonstrated that the choice of precursor has a strong effect on the reduction of nitrate (NO3−) using zero-valent copper (Cu0) synthesized by sodium borohydride (NaBH4). Different precursors: CuSO4, CuO, Cu2O, Cu powder, and Cu mesh were used to reduce NO3− at 677 mg-N/L under the reducing conditions of NaBH4. Compared with the prehydrolyzed samples, those prepared without prehydrolysis exhibited lower reduction rates, longer times and higher concentrations of nitrite (NO2−) intermediate. It was found that one-time addition of NaBH4 resulted in higher reduction rate and less NO2− intermediate than two-step addition. Results showed that Cu0 from CuSO4 possessed the smallest particle size (890.9 nm), highest surface area (26.0 m2/g), and highest reaction rate (0.166 min−1). Values of pseudo-first-order constant (kobs) were in the order: CuSO4 > CuO > Cu2O > Cu powder >Cu mesh. However, values of surface area-normalized reaction rate (kSA) were approximately equal. It was proposed that NO3− was reduced to NO2− on Cu0, and then converted to NH4+ and N2, respectively; H2 generated from both NaBH4 hydration and Cu (II) reduction contributed to NO3− reduction as well.

Familial amyloid polyneuropathy (FAP) due to amyloidogenic transthyretin (TTR) is often associated with impairment of thermonociceptive functions. This study investigated skin innervation and its clinical significance in genetically defined FAP due to a hot-spot Ala97Ser TTR mutation (Ala97Ser).Skin biopsies were performed on the distal leg of patients with Ala97Ser, and intraepidermal nerve fiber (IENF) densities were quantified.There were 19 unrelated patients with Ala97Ser manifesting a late-onset (59.47 +/- 5.70 years) generalized neuropathy with disabling motor, sensory, and autonomic symptoms. Against a background of a slowly progressive course, 7 patients (36.8%) exhibited additional rapid declines in neurologic deficits, which were associated with elevation of the protein content in the CSF (p0.001). The IENF density was markedly reduced in Ala97Ser patients compared to age- and gender-matched controls (0.99 +/- 1.11 vs 8.31 +/- 2.87 fibers/mm, p0.001). Skin denervation was present in all patients and was lower in patients with a higher disability grade (0.17 +/- 0.26 vs 1.37 +/- 1.16 fibers/mm, p = 0.003). Albuminocytologic dissociation in the CSF was observed in 14 patients (73.7%), and the IENF density was negatively correlated with the CSF protein concentration (p = 0.015).Skin denervation was common in Ala97Ser, and degeneration of cutaneous nerve terminals was correlated with the severity of clinical phenotypes and the level of CSF protein.

A non-uniform rectangular-ring slot antenna is presented to achieve both wider impedance and axial-ratio (AR) bandwidths. A simple design process, composed of three steps, is developed to obtain the required performances. Because of the better performances and less design time, the proposed antenna will be a good choice for the wideband circularly polarized operation. The first one of the three design steps is to determine the size of the uniform square-ring slot and feeding point by the required center frequency. The second one is to achieve circular polarization operations by widening the upper slot. However, the center frequency of the proposed antenna is shifted to higher frequency owing to the shortening of the average current path. Finally, the center frequency of the proposed antenna is fine tuned to the required center frequency by resizing the parameters of the proposed antenna. An antenna design example is given for the application of WLAN 2.4 GHz. Following the three design steps, the simulated...

The unwanted high threshold voltage (V"t) is the major challenge for metal-gate/[email protected] CMOS especially at small equivalent-oxide-thickness (EOT). We have investigated the high V"t issue that is due to flat-band voltage (V"f"b) roll-off at smaller EOT. A mechanism of charged oxygen vacancies formed by interface reaction was proposed to explain the V"f"b roll-off effect. This interface reaction can be decreased by inserting a thin interfacial SiON and using novel low temperature process. The self-aligned and gate-first metal-gate/[email protected] CMOSFETs using these methods have achieved low V"t and good control of V"f"b roll-off at small 0.6-1.2nm EOT.

Chemical precipitation method utilizing calcium salts has been extensively used to treat fluoride-containing wastewater from semiconductor manufacturers. The major objective of this study was to investigate coagulation-flocculation of calcium fluoride precipitates (Ca F2 ) . Residual fluoride concentration of lower than 15 mg∕L , the effluent standard, was found when molar ratio of calcium to fluoride, [ Ca2+ ∕ F− ] , was 0.5 and pH ranged from 6.5 to 8.5. The fine precipitates of Ca F2 were further flocculated by polyaluminum chloride (PAC) and anionic polyelectrolyte, polyacrylic acid (PAA) with different molecular weight, to facilitate better solid-liquid separation. Experimental results indicated that both PAC and PAA with low to medium molecular weight could remove Ca F2 precipitates effectively. Satisfactory removal efficiency was achieved at lower dosage when PAC and PAA were used in combination. Recycling of Ca F2 precipitates or Ca F2 sludge did not enhance removal of fluoride or Ca F2 precipitat...

The aim of this work was to examine the ropiness of Lactobacillus helveticus BCRC14030, L. helveticus BCRC14076, and Streptococcus thermophilus BCRC14085, and evaluate the effect of fermentation time on exopolysaccharides (EPS) production by the ropy strain. Each of the three strains was inoculated in skim milk medium and incubated in a fermenter for 0–84 h at pH 5, 37 °C. The fermented samples, containing a net volume of 300 ml skim milk, were withdrawn at intervals of 0, 12, 16, 24, 32, 36, 48, 60, 72, and 84 h for determinations of ropy condition, EPS yield, and molecular mass. EPS with ropiness values of 11.3–21.0 mm, produced from L. helveticus BCRC14030 at 32–60 h demonstrated the ropy nature of the strain. Those EPS were composed of high molecular mass of 26,500 kDa. The highest EPS yield of 0.73 g l−1 from this strain was observed (P

Although zero-valent iron represents a promising approach for reduction of nitrate (NO(3)(-)) in water, its application in concentrated nitrate is limited by surface passivation. In this study, an alternative approach using in situ synthesized zero-valent copper (Cu(0)) produced by borohydride (NaBH(4)) was investigated. Complete reduction was observed within 55 min by reacting 677 mg-N/L of NO(3)(-) with CuO (0.312 g/L) and NaBH(4) (4.16 g/L) at 60 °C. The pseudo-first-order rate constant was 0.059 min(-1), and it increased threefold when the CuO dose was increased to 1.24 g/L. Increasing the NaBH(4) dose produced less nitrite (NO(2)(-)) throughout the experiments, indicating that it is the primary agent for reducing NO(2)(-). The initial pH exerted a significant effect on the reaction rate, and NO(3)(-) was rapidly reduced when the initial pH was less than 4. Based on the research findings, possible reaction pathways for NO(3)(-) reduction by Cu(0) are proposed in this work.

A novel Cycle Alarm Point (CAP) inspection is proposed to monitor PCM cycling degradation. The degradation appears in two stages - (1) right shift of R-I during moderate cycling degradation, and (2) left shift of R-I when cycling damage is severe. We further propose an In-Situ-Self-Anneal (ISSA) procedure, such that once a CAP signal is detected, the annealing procedure is issued to rejuvenate the cells. We demonstrate, for the first time, PCM cycling degradation can be recovered repeatedly. This opens a new window to extend PCM endurance and reliability for storage class memory (SCM) applications.

This paper presents an interpretation of the piezocone test in clay based on a simplified theoretical solution of cavity expansion in modified Cam clay. The cone resistance and the pore pressures measured on the cone tip and just behind the cone tip are interpreted using the framework of cavity expansion theories with due consideration of the effect of strain rate and the initial stress state. Methods for estimating the overconsolidation ratio, the undrained shear strength and the rigidity index of clay are proposed. A comparison of results obtained from the proposed methods with published data and limited field data collected in the Singapore marine clay indicates the validity of the proposed analysis methods.

This paper presents an analysis of the undrained expansion of a cavity in modified Cam clay. The problem is formulated in small strain in the elastic zone and large strain in the plastic zone. Exact closed-form solutions of the effective stresses around the expanded cavity are presented. Closed-form expressions for the excess pore water pressure and the total stresses have also been derived based on a simplified assumption regarding the shear stress variation around the cavity. The analytical solution shows clearly the influence of the overconsolidation ratio on the excess pore water pressure induced by cavity expansion. As both the excess pore water pressure and the cavity pressure are expressed explicitly in terms of the primitive modified Cam clay parameters, the solutions may provide a theoretical basis for the interpretation of in-situ tests such as the piezocone test and the pressuremeter test.

Studies of 2-D atomic hydrogen at high densities on helium surfaces have been plagued by the heating of the surfaces due to recombination, which dissipates more than 52,000K for each recombining pair of atoms in the cell. When hydrogen recombines on a surface, it deposits less than 4% of its energy at the point of recombination and the rest is carried off by the excited molecule. We have designed a maze to absorb most of this energy, and carried out a Monte Carlo simulation to show that approximately 87% of the energy is dissipated in the maze, preventing the surface from getting excessively heated, even at high surface densities. This simulation varies the number of inelastic collisions with the maze wall for complete relaxation, the fraction of elastic collisions, and the angular distribution of excited molecules desorbing from the walls.

Projection optics is a means to reduce the spatial energy density variations on the target during laser ablation. Using projection optics to study the interaction between a spatially uniform 248 nm excimer laser beam and a YBa2Cu3O6+x target we observe a well-defined threshold fluence of 1.0 J/cm2. Below this threshold non-stoichiometric ablation results in an dramatic change in target morphology and in a decay of the ablation rate. Above this threshold the stoichiometry of the target is conserved. The roughness of the deposited films increases along with the increase in roughness of the target above the threshold. Thus it is clear that in order to obtain flat stoichiometric films one should use a narrow fluence window just above the threshold.

In this paper, the microscopic mechanism of rutting formation is studied by the Discrete Element Method (DEM). The particles in discontinuous asphalt mixtures are discretized into circular rigid particles by DEM, then the initial model is created in accordance with the actual pavement. The displacement vector changes of particles under loading and the process of rutting formation are presented in this paper. The asphalt pavement model has been built to simulate the material properties of asphalt pavement by the PFC2D software. At the same time, the displacement vector changes in each layer have been analyzed under loading. In addition, the mechanisms of permanent deformation have been studied and the rutting formation process of asphalt pavement has been simulated. The results show that the Discrete Element Method used to study permanent deformation characteristics of asphalt pavement is reasonable and feasible.

Road condition surveys show that the long and steep climbing section of asphalt pavement is one of the regions with the most significant rutting that seriously affects the road performance. And rutting is more serious for steeper longitudinal slope. In this paper, the changing rule of shear stress and its distribution characteristics in pavement are analyzed on conditions of different longitudinal slope and different horizontal attachment coefficients by a finite element method. The results show that the maximum shear stress is less subjected to the component of gravity when the longitudinal gradient changes. Due to the existence of longitudinal gradient, the changes of the adhesion between tires and road affect the shear stress significantly. The peak maximum shear stress gradually moves to the surface with increasing the horizontal force coefficient. The research results presents guides on how to prevent and control distresses for asphalt pavements on a long and steep slope. .

Design and reconfiguration approaches for high harvest rates and parallel on-wafer diagnosis of linear arrays are described. The defect-tolerant designs use multiplexers to switch intercell connections and guarantee that the wire length between any two logically adjacent cells is constant, independent of fault distribution. The designs are appropriate for implementing linear arrays of wafer-scale memory and processor architectures. The harvesting of fault-free cells into a linear array is a percolation process; there exists a critical cell yield such that the harvest rate drops to zero (approaches 100%) if the cell yield is below (above) the critical value. Finding a maximum-size linear array for a given set of fault-free cells is polynomial time solvable if only the interconnections between fault-free cells are utilized, but is NP-complete if the interconnections between all cells are utilized. A heuristic reconfiguration algorithm utilizing the interconnections between all cells is presented. Application of boundary scan to parallel testing and on-wafer diagnosis of the arrays is described. >

The stress history as indicated by the profile of overconsolidation ratio (OCR) of a soil deposit is one of the most dominant factors that influence the engineering behaviour of the soil. Its assessment, which is traditionally based on the laboratory oedometer test, is not often satisfactory. The problem arises from inevitable sample disturbance and the high cost of a detailed investigation. These difficulties can be overcome by the use of in situ tests. The field vane test, the piezocone test, and the dilatometer test are three such methods that provide indirect means for the estimation of the OCR for clay deposits. A number of empirical correlations are available for this purpose. Calibration of these correlations against results of site investigation in Singapore and Malaysian marine clays reveals the usefulness of these test methods in profiling the OCR for Recent clay deposits. Key words: clay, in situ test, overconsolidation ratio, preconsolidation pressure, stress history.

The current practice for the design of large-diameter bored piles in residual soils in Singapore is based on the calculated static capacity of the piles. Insufficient consideration of the load-transfer mechanism and overreliance on pile load tests have led to conservative designs. A better alternative is to adopt a load–displacement analysis method that provides information on the load distribution along the pile and the complete load–displacement relationship. Results of full-scale load tests on instrumented piles indicate that bored piles in residual soils in Singapore behave in the same way as in stiff clay and weak rocks elsewhere in that the load transfer at the working load is dominated by shaft friction. Simple correlations exist between the standard penetration resistance and the load-transfer parameters. An example illustrates that the proposed design procedure that uses these simple correlations and the load-transfer method is an improvement over present design methods. Key words: bored piles, cast-in-place piles, design, drilled piers, field test, load transfer, residual soil, shaft resistance.

The authors investigate wafer probing strategies for the diagnosis of repairable VLSI and WSI (wafer scale integration) structures based on integrated diagnosis and repair. Knowledge of the repair strategy, the probability of each unit being good, and the expected test time each unit are used by the diagnosis algorithm to select units for wafer probe testing. The general problem is described followed by an examination of a specific case. Wafer probe diagnosis of k-out-of-n systems is analyzed and optimal diagnosis algorithms are derived. A compact representation of the optimal diagnosis scheme which needs O(n/sup 2/) space and can be generated in O(n/sup 2/) time is described. >

Using projection optics we made a detailed study of the interaction of a spatially uniform 248 nm excimer laser beam and a 99% dense YBa2Cu3O6+x target. Below a threshold fluence of 1 J/cm2 the roughness of the irradiated target increases dramatically due to non‐stoichiometric ablation. The overall target surface composition becomes increasingly Y rich and Cu poor, while the opposite is found for the corresponding ablated thin films. Above the threshold fluence the composition of the ablated target surface is conserved. As a result of the energy homogeneity of the laser beam obtained by means of projection optics, the optimization of the deposition parameters has been improved leading to the reproducible fabrication of flat, stoichiometric YBa2Cu3O7 films with Tc0’s over 91 K.

The purpose of this study was to investigate the clinical usefulness of the color Doppler vascularity index (CDVI) in patients with colon cancer before surgery. Forty-four patients with sonographically visible tumor mass of colon cancer were investigated. The CDVI of each tumor was determined using transabdominal color Doppler ultrasound. The CDVI was defined as the ratio of the number of the colored pixels within a tumor section to the number of total pixels in that specific tumor section and was calculated by using Encomate software (Electronic Business Machine Co. Ltd., Taipei, Taiwan). The correlation between the CDVI and clinicopathological factors, mode of recurrence, and patient survival was studied. For comparison, microvessel density (the mean number of microvessels in three areas of highest vascular density at x200 magnification) of the tumors of these 44 patients was also evaluated by using immunohistochemical staining of surgical specimens with anti-CD34. The microvessel density was not correlated with Dukes' classification, clinicopathological factors, and survival. The CDVI was significantly higher in the patients with lymph node metastases and vascular invasion than in those without such metastases and invasion (P = 0.006 and P = 0.0098, respectively). Moreover, in patients with a high CDVI (15%) and positive vascular invasion, survival was significantly poorer than in those with low CDVI (or = 15%) and negative invasion (P = 0.0037 and 0.0039, respectively). Multivariate analysis indicated that liver metastasis, vascular invasion, and CDVI are independent prognostic factors in the patients with colon cancer. According to the mode of recurrence in 36 patients who underwent curative resection, the frequency of the distant organ recurrence was significantly higher in the high CDVI group (40%) than in the low CDVI group (0%). The CDVI is a good preoperative indicator of recurrence and patient survival in colon cancer. Thus, the CDVI may be helpful in stratifying patients for adjuvant therapy.

Using a statistical analysis of high-speed scanning tunneling microscopy movies, we determine the formation energy of kinks in the steps on Ag(113) to be W0=1280±25 K. To examine the step distance dependence of this energy we compare our result with the kink formation energy previously measured on the Ag(115) surface. In addition, we perform effective medium theory (EMT) calculations of kink energies on silver surfaces with various orientations. Both experiment and calculations show that the kink creation energy is almost independent of the distance between the steps.

The fact that both aluminum hydroxide adjuvant and proteins have a pH dependent surface charge means that electrostatic forces play a role in the adsorption of proteins by aluminum hydroxide adjuvant during the preparation of vaccines. The objective of this study was to examine the contribution of the electrostatic attractive force in the adsorption of proteins by aluminum hydroxide adjuvant. Since the surface charge characteristics of aluminum hydroxide adjuvant can be modified by the adsorption of phosphate anion, a series of aluminum hydroxide adjuvants were prepared by treatment with various concentrations of phosphate anion. The isoelectric points (iep) of these adjuvants ranged from 11.0 to 4.6 and the electrophoretic mobilities at pH 7.4 ranged from 2.0 to -3.3 microns cm/V s. The line broadening of the (020) band of the X-ray diffraction pattern indicated that treatment with phosphate anion did not change the primary crystallite dimension. Adsorption at pH 7.4 of positively charged lysozyme (iep = 11.1) was directly related to the negative surface charge of the adjuvant. No adsorption occurred when the surface charge was positive. In contrast, negatively charged ovalbumin (iep = 4.6) was adsorbed by all of the adjuvants at pH 7.4, although the adsorptive capacity was the greatest when the surface charge was positive. The results indicate that adsorptive forces in addition to the electrostatic attractive force play an important role in the adsorption of some proteins by aluminum hydroxide adjuvant. It is believed the structurally flexible proteins, like ovalbumin, exhibit more complex adsorption behavior than structurally rigid proteins, like lysozyme, for which adsorptive behavior can be explained by electrostatic forces.

We describe a high-speed programmable-temperature scanning tunneling microscope (STM) for the study of dynamical processes and the measurement of various energies on metal surfaces. The programmable-temperature STM operates in the temperature range from 60 to 1000 K. Over a temperature window of 300 K it can keep one particular surface area in view. We present two experimental results obtained with this instrument. The first concerns the energetics of a vicinal surface, Ag(115), and their relation with the surface roughening transition. The second treats the diffusion dynamics of kinks in steps on the (110) surface of Au.

This study was aimed at assessing the efficacy and tolerability of rifabutin for the re-treatment of cases of chronic, multidrug-resistant pulmonary tuberculosis. The study design was self-controlled, single center. Rifabutin was administered as part of an individual-tailored multidrug regimen. In-patients suffering from pulmonary tuberculosis, infected with Mycobacterium tuberculosis bacilli resistant to isoniazid, rifampicin and other drugs with progressive disease unresponsive to prior courses with standard anti-tuberculosis medications were treated. Overall, 43 patients were enrolled and treated with rifabutin at 300 or 450mg/day according to body weight in conjunction with available anti-tuberculous drugs for a mean time of 353 days (range 42-678). Of these, 36 met all eligibility criteria (i.e. positive baseline culture of sputum with bacilli resistant to rifampicin at least) and were retained for the analysis of efficacy. Seventeen patients (47%) achieved a sustained conversion to a negative culture of sputum in a mean time of 47.7 days with a range of 14-120 days. Treatment prevented deterioration in most patients and resulted in clinical and radiological cure or marked improvement in more than half of cases. No correlation was found between treatment outcome and use of medication concomitant to rifabutin or susceptibility of bacilli to the drugs used. Four deaths occurred due to disease progression, in no case being related to study drugs. Ten patients reported a total of 18 adverse events that led to treatment discontinuation in 5 cases. Rifabutin should be considered for inclusion in regimens for cases of pulmonary multidrug-resistant tuberculosis which fail to respond to previous therapy.

The role of flow cytometry in predicting prognosis for cervical carcinoma remains unclear.Flow cytometric analysis was performed on tissues, fixed in formaldehyde solution and embedded in paraffin, from 411 patients with Stage IB or II cervical carcinoma who had been treated with radical abdominal hysterectomy and bilateral pelvic lymphadenectomy.DNA aneuploid-multiploid tumors were found in 37.5%, tetraploid in 4.6%, and diploid-peridiploid in 57.9%. Five-year recurrence-free survival rates of the three groups were 74.3%, 77.8%, and 76.4%, respectively (P0.05). DNA aneuploidy and DNA index (DI) of greater than 1.3 were highly correlated to parametria extension. In univariate analysis, pelvic lymph node metastases, stage, parametrial extension, depth of cervical stromal invasion, tumor size, and DI (1.3, 1.4, 1.5 as breakpoint) were significant prognostic factors. DNA ploidy, S-phase fraction, and S-G2M fraction were not significant. In multivariate analysis, DI of greater than 1.3, pelvic node metastases, clinical Stage II, and depth of stromal invasion greater than two-thirds of full cervical thickness were independent and significant variables. The prognostic index (PI), defined by the model, was able to categorize the patients into three distinct risk groups. The 5-year recurrence free survival rates of the low-, intermediate-, and high-risk groups were 89.5%, 73.0%, and 58.9%, respectively (P0.0001).The prognostic value of the DI as a single variable is promising and warrants additional investigation to establish its appropriate use.

We have sequenced an HDV RNA from an acute delta hepatitis patient from the Nauru Islands. By comparison with other HDV sequences previously reported, we have identified three conserved regions: the first one is the sequence around the catalytic cleavage site for genomic-sense RNA; the second is the corresponding site for the antigenomic sense RNA; and the third is the sequence encoding the middle domain of the hepatitis delta antigen. We have shown that the middle domain of the delta antigen can bind specifically to the HDV RNA. This binding was demonstrated both in vitro and in the purified virion. It was suggested that this RNA-protein interaction is important for HDV RNA replication. We also suggest that the conserved sequences provide ideal primers for use in polymerase chain reaction (PCR) in clinical diagnosis of HDV infections. We recommend the use of nucleotides 870-900 and 690-720 (Makino et al., 1987a) as primers for routine screening.

The reliability of results of laboratory tests on soils depends on the specimen quality or the initial specimen condition. The quality of specimens prepared using different methods, from clay samples extracted using different techniques and subjected to different periods of storage, can be evaluated based on the measurement of residual porewater pressure. For a laboratory-fabricated normally consolidated clay, the residual porewater pressure decreases when using an inferior sampling technique or preparation method and when the storage time increases, with the effect from the method of specimen preparation dominating. Results of oedometer tests indicate that consolidation properties are noticeably affected by the initial specimen condition, and reasonably strong correlations exist between the preconsolidation pressure and the coefficient of volume compressibility of the clay and the residual porewater pressures in the test specimens. These corrections can be potentially applied to natural clays, although prior verification is necessary.

The stress history as indicated by the profile of overconsolidation ratio (OCR) of a soil deposit is one of the most dominant factors that influence the engineering behaviour of the soil. Its asses...

On implante des protons dans la region epitaxiale dopee au phosphore d'une grille de transistor isolee. On etudie les changements de resistance en fonction des differentes doses d'implantation