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A theoretical investigation for the conductivity of single walled nanotube films is carried out with an effective medium model in the Terahertz region. The results are compared with the recent experiment and a decrease of the real conductivity with increasing frequency is predicted. Meanwhile, the off-diagonal components of the dielectric function of single-walled carbon nanotube films based on the magnetooptical effects are also shown. (C) 2003 MAIK "Nauka / Interperiodica".

A theoretical investigation for the magneto-optical Kerr effect of InSb in Terahertz region is carried out. The results show an enhancement of Kerr effect both at room temperature and a low temperature in Terahertz region. The enhancement of Kerr spectrum due to the plasma edge effect is put forward. Meanwhile, the magneto-optical Kerr effect spectrum of InSb in the different external magnetic fields are discussed. The peak shifts of the Kerr rotation under different external magnetic fields and temperatures are discussed.

Background: Reshaping of the face with age is a result of volume change and loss of support. It is not well understood which tissues are involved in this process. Recent publications suggest that adult bone growth may have a significant role. Objective: We report a longitudinal cephalometric analysis of midfacial growth in adults to determine the role of bone in facial aging. Methods: The Behrents modification of the Bolton Cephalometric study in patients up to age 83 was reviewed. A trigonometric analysis targeted orbital and anterior maxillary growth. Results: Facial bone growth is shown to continue throughout adulthood. Anterior descent creates increased bone projection. Conclusions: The appearance of facial aging is caused by attrition of soft tissue volume and loss of support. The deficiency of maxillary bone projection seen in some patients, with tear trough depression and negative vector eyelid (polar bear), preexists adulthood and is unmasked with age.

High-vacuum electron-beam evaporation method is used for large area, metal-nucleated germanium (Ge) nanodots and nanocones on Si3N4/Si preparation. Nanodot and nanocone arrays with uniform size in bulk-quantity are synthesized using titanium (Ti) nanocrystals as nucleating center at 750degreesC with different Ge deposition amount, respectively. The morphology evolution from nanodot to nanocone is studied by atomic force microscopy (AFM). The structure of the prepared sample is characterized by X-ray diffraction (XRD) and Raman scattering. Ge nanocones formed by this convenient fabrication process could have potential applications on nanoelectronics and vacuum electron field emission. (C) 2003 Elsevier Science Ltd. All rights reserved.

Quaternary InAlGaN film has been grown directly on top of low-temperature-deposited GaN buffer layer by low-pressure metalorganic vapor phase epitaxy. High-resolution X-ray diffraction and photoluminescence (PL) results show that the film has good crystal quality and optical property. Temperature-dependent PL and time-resolved PL (TRPL) have been employed to study the carriers recombination dynamics in the film. The TRPL signals can be well fitted as a stretched exponential function exp[-(t/tau)(beta)] from 14 to 250 K, indicating that the emission is attributed to the radiative recombination of excitons localized in disorder quantum nanostructures such as quantum disks originating from indium (In) clusters or In composition fluctuation. The cross-sectional high-resolution electron microscopy measurement further proves that there exist the disorder quantum nanostructures in the quaternary. By investigating the dependence of the exponential parameter beta on the temperature, it is shown that the multiple trapping-detrapping mechanism dominates the diffusion among the localized states. The localized states are considered to have two-dimensional density of states (DOS) at 250 K, since radiative recombination lifetime tau(r) increases linearly with increasing temperature. (C) 2002 Elsevier Science B.V. All rights reserved.

A new method, high-vacuum electron-beam co-evaporation is used to prepare silicon nanocrystals (Si NCs) embedded in Al2O3 dielectric matrix in the form of thin films. Silicon and Al2O3 are co-evaporated by two electron guns at the same time at room temperature with the pressure below 1×10−5 Pa. After evaporation, annealing in N2 ambient at 500 and 800 °C for 1 h is performed. X-ray diffraction and atomic force microscopy are used to estimate the diameter of the Si NCs and check the morphology of the co-evaporation film respectively. X-ray photoelectron spectroscopy is used to investigate the chemical state of Si and Al in the as-prepared and annealed samples. Electrical properties of the Si NCs are investigated and resonant tunneling due to three dimensional quantum confinements is observed at room temperature.

The process design of the thin-walled injection molding is investigated in this study. It was realized that the behavior of warpage in injection molding parts was affected by different process conditions such as melt temperature, mold temperature, packing pressure and injection rate. Experimental design of Taguchi method was used to determine the process conditions. Both the numerical simulations and experiments were conducted to study the effects of the process conditions on the warpage of a cap model. The proper processing parameters were also identified by the experimental design. The packing pressure was found to be the most important factor on the warpage of a thin-walled part. The experimental design done by numerical simulations also provided proper results in terms of warpage reduction.

This work intends to quantitatively analyze on pathological grade of glioma using Magnetic Resonance (MR) diffusion weighted imaging (DWI) and exploring the relativity of pathological grade and Apparent Diffusion Coefficient (ADC) value of MR diffusion weighted imaging.40 patients with glioma accepted the MR diffusion weighted imaging to measure the ADC value of tumor with 3.0T MR machine before the surgery. Tumor samples were sent for pathologic diagnosis and tumor cell density measurement after the operation. The acquired data were analyzed statistically.The ADC values of low-grade (WHO I-II) glioma were higher than that of high-grade (WHO III-IV), but the cell density of low-grade glioma was apparently lower than that of high-grade glioma. The ADC values and density of tumor cells were negatively correlated with WHO malignant grades, while the density of cells of glioma was positively correlated with WHO malignant grades.MR diffusion weighted imaging is an objective and effective examination method.

Biofeedback treatment of prehypertension: analyses of efficacy, heart rate variability and EEG approximate entropy

Background Isoliquiritigenin (ISL) is a natural compound in licorice and has chemopreventive and anti-tumour activities. ISL induces tumour cell apoptosis and DNA damage in cervical cancer cells, and induces ATM-associated DNA repair signalling. However, ISL down-regulates ATM and phosphorylated ATM (p-ATM) in human oral squamous cell carcinoma (OSCC) cell lines. The aim of this study was to investigate the ATM inhibition mechanism of ISL in OSCC cell lines. Methods mRNA and protein expression were detected by reverse transcription-PCR (RT-PCR) and western blotting, respectively. The promoter activity was detected by firefly and renilla luciferase reporter system. DNA damage was analysed by terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay and gamma-H2A.X protein expression. microRNA expression was detected by quantitative RT-PCR. Findings ISL induced OSCC cell cycle G2/M phase arrest, apoptosis, and DNA damage. However, the DNA repair-associated ATM and p-ATM proteins were down-regulated, ATM mRNA levels were unchanged, and the p-ATM downstream signals were inhibited. The down-regulated ATM protein expression might be caused by promoter activity inhibition, microRNA over-expression, and protein degradation. The ATM promoter in OSCC cell line was unchanged after ISL treatment. The microRNAs miR203a and miR421, which target ATM, were both down-regulated. When blocking caspase activity with Z-DVED-FMK, the down-regulation of ATM was reversed. Interpretation ISL-inhibited ATM expression was not regulated by miR203a and miR421 at a transcriptional level. The down-regulation of ATM was caused by ISL activating caspase. These data indicate that ISL induced apoptosis and inhibited DNA repair in OSCC. ISL might be a promising chemopreventive agent against oral cancer.

Purpose: Primary angle-closure glaucoma (PACG) is more prevalent among Chinese than whites. The authors tested the hypothesis that Chinese have shallower anterior chambers than do whites, a factor that may be related to PACG prevalence. Methods: The authors compared anterior chamber depth, axial length, radius of corneal curvature, and refractive error among 531 Chinese, 170 whites, and 188 blacks older than 40 years of age using the same model of instruments and identical technique. Results: Mean anterior chamber depth and axial length did not differ significantly for the three groups. Whites had a significantly higher prevalence of hyperopia >2 diopters than did Chinese. Radius of corneal curvature was significantly smaller among Chinese than whites or blacks. Conclusions: These results suggest that Chinese do not differ on a population basis from other ethnic groups in many of the biometric risk factors known to be of importance for PACG. It will be necessary to identify other ocular biometric parameters to explain the excess burden of PACG among Chinese, which may improve the effectiveness of screening for this disease in all populations.

This paper is concerned with a gain-scheduled approach for the energy management strategy (EMS) development of a parallel hybrid electric vehicle (PHEV). The aim is to determine the power split ratio between engine and battery that minimizes the vehicle fuel consumption. First, the system is modelled under linear fractional transformation (LFT) form with varying parameters (velocity and battery capacity) represented as an uncertainty blocks. Then a discrete-time linear parameter varying (LPV) controller which is scheduled by the values of varying parameters is synthesized using the approach proposed in Apkarian and Gahinet (1995). Finally, the performances of the LPV controller are analysed based on simulations in the frequency and time domains.

Designing and implementing assessment tasks in large-scale undergraduate science courses is a labor-intensive process subject to increasing scrutiny from students and quality assurance authorities alike. Recent pedagogical research has provided conceptual frameworks for teaching introductory undergraduate microbiology, but has yet to define best-practice assessment guidelines. This study assessed the applicability of Biggs’ theory of constructive alignment in designing consistent learning objectives, activities, and assessment items that aligned with the American Society for Microbiology’s concept-based microbiology curriculum in MICR2000, an introductory microbiology course offered at the University of Queensland, Australia. By improving the internal consistency in assessment criteria and increasing the number of assessment items explicitly aligned to the course learning objectives, the teaching team was able to efficiently provide adequate feedback on numerous assessment tasks throughout the semester, which contributed to improved student performance and learning gains. When comparing the constructively aligned 2011 offering of MICR2000 with its 2010 counterpart, students obtained higher marks in both coursework assignments and examinations as the semester progressed. Students also valued the additional feedback provided, as student rankings for course feedback provision increased in 2011 and assessment and feedback was identified as a key strength of MICR2000. By designing MICR2000 using constructive alignment and iterative assessment tasks that followed a common set of learning outcomes, the teaching team was able to effectively deliver detailed and timely feedback in a large introductory microbiology course. This study serves as a case study for how constructive alignment can be integrated into modern teaching practices for large-scale courses.

To study the incidence and outcome of GB virus C (GBV-C) infection in blood recipients. Serum samples collected in a prospective study were examined for GBV-C RNA by a nested polymerase chain reaction assay. Among the 400 adults who underwent cardiac surgery, 40 were positive for GBV-C RNA, including six whose pretransfusion sera were already positive and seven coinfected with hepatitis C virus (HCV) during transfusion. The risk of transmission was estimated to be approximately 0.46% per donor. GBV-C viremia was detectable 1 week after transfusion and could persist for 8 years. However, no evident symptoms or signs were noted in the 25 patients infected by GBV-C alone, and the average peak serum alanine aminotransferase activity was 31 IU/L only (range, 12 to 123), with persistently normal levels in 20 patients. In the seven patients coinfected with HCV, the clinical courses of posttransfusion hepatitis were similar to those infected by HCV alone. In eight patients with posttransfusion non-A approximately E hepatitis, only one was positive for GBV-C RNA. Sixty samples were chosen to test hepatitis G virus (HGV) sequences, 26 of the 30 GBV-C positives were positive for HGV RNA in contrast to none of the 30 GBV-C negative samples. In conclusion, GBV-C can be transmitted by transfusion in approximately 9% of patients who underwent cardiac surgery. Nevertheless, this virus does not seem to cause classic hepatitis in most instances.

Two existing rigid band models of low temperature luminescence in a-Si:H are compared and their difficulties examined. A new model is proposed which includes the essential features of both, and which explains the width and Stokes shift of the spectra without problems of large excitation power shifts in peak position.

An in situ doping approach was adopted to synthesize single-crystalline Sn-doped In2O3 [indium tin oxide (ITO)] nanowhiskers. Similar synthesis strategy could be used in the production of various doped metal oxide nanowhiskers. The growth mode of ITO nanowhiskers was discussed based on a self-catalytic vapor–liquid–solid growth mechanism. At room temperature, a photoluminescence peak at 510nm was observed, which was likely related to the surface defects of ITO nanowhiskers. In air ambient, the resistivity of individual ITO whisker was measured to be 0.40Ωcm, which was much higher than that of ITO films. A possible explanation for the high resistivity was proposed based on the influence of surface oxygen absorption.

Using argon as the transporting gas, freestanding macroscopic ZnO strands have been synthesized by evaporating metal zinc pellets at 900 °C in a quartz tube. Scanning electron microscopy images show that the macroscopic ZnO strands are self-twined by ZnO nanowires with a diameter in the range of 20–30 nm. A ZnO strand synthesized under larger argon flux contains more oxygen vacancy, which will result in a stronger green emission at 2.43 eV. Under illumination with a power of 10 W, the photosensitivity of the ZnO strand is found to be about 800 at the bias voltage of 20 V. It is also experimentally demonstrated that the recovery time of the ZnO strand is relatively long due to the dominating surface process.

In the increasingly competitive global knowledge marketplace, Australian tertiary educators are looking to enrich their program offerings by providing authentic learning experiences for their students. In the biological sciences, this authenticity is best represented by hands-on inquiry and laboratory experimentation, often within the context of research internships. Authentic Large-Scale Undergraduate Research Experiences (ALUREs) aim to broaden the scope of these learning experiences by embedding research into coursework activities accessible by all students within the program. These experiences can promote learning gains in laboratory, analytical, and critical thinking skills, providing students with a transferable skillset applicable to many career paths across the science sector.

Germanium (Ge) nanostructures embedded in Al2O3 dielectric are synthesized by the vacuum electron-beam co-evaporation method. A clear blue-shift of the absorption edge and a large third-order nonlinear optical susceptibility are observed due to the quantum confinement effects. Current–voltage and capacitance–voltage characteristics of metal–insulator–semiconductor structures containing Ge nanocrystals are studied in the dark and under illumination. Negative photoconductivity due to the screening effects of the negatively charged Ge nanocrystals is experimentally demonstrated.

The conductivity of single-walled nanotube films is investigated with a combination of Maxwell-Garnett (MG) and Drude-Lorentzian (DL) model in terahertz region. A theoretical investigation for the recent experiment is given and a decrease of the real conductivity with increasing frequency is predicted. Meanwhile, the real part of dielectric function of single-walled carbon nanotube films is displayed. (C) 2003 Elsevier Science B.V. All rights reserved.

To study the incidence of human T-cell lymphotropic virus (HTLV) after blood transfusion in Taiwan, serum samples from 699 patients in a prospective study were examined for seroreactivity of anti-HTLV. By an enzyme immunoassay, 9 of the 699 recipients were repeatedly positive. Serial serum samples of these 9 patients were then confirmed with a Western blot analysis and with a polymerase chain reaction (PCR) assay for HTLV-I genome. Four were already positive for anti-HTLV before transfusion, 1 carried antibodies to HTLV-I transiently after transfusion, and only 4 cases had de nova seroconversions. These patients and their family members were called back and tested for HTLV- I genome in the peripheral blood mononuclear cell (PBMC) and plasma. All the serologically positive patients, except the “transient one,” were positive for HTLV sequences in the PBMCs. Viral sequences could also be detected in several serum or plasma samples. In the family members, only the spouse of a pretransfusion-positive patient was infected. These results suggested that approximately 0.6% of the blood recipients were infected by HTLV-I through transfusion in Taiwan, and that the frequency of intrafamilial HTLV-I transmission is low. We also observed the unusual coinfection by both HTLV-I and hepatitis C virus in 2 patients, and superinfection of hepatitis C virus after blood transfusion in 1 HTLV-I carrier. Cases of coinfection suggest a prevalence of both viruses in blood donors and warrant further screening.

A one-dimensional conductivity barrier model is introduced to describe the dielectric response and conductivity of BiFeO 3 (BFO) and (Bi 0.95 Nd 0.05 )FeO 3 (BFO-5%Nd) ceramics as functions of temperature and frequency. Good qualitative fits of conductivity and dielectric permittivity in the intermediate-temperature region (500–800 K) are obtained with intrinsic barriers of B=8700 K (for BFO) and B=8400 K (for BFO-5%Nd), and extrinsic barriers of Δ=2500 K (for BFO and BFO-5%Nd). The phase-shifted conductivity is responsible for a step-like dielectric relaxation in the region of 500–800 K. The experimental conductivity departs from the conductivity-barrier-model fit below 650 K. This deviation is likely caused by the magneto-electric coupling near the antiferromagnetic-paramagnetic transition. This work suggests that the 5% mole Nd-substitution can stabilize the perovskite structure in BFO ceramic.

Thoria- or molybdena-promoted Co/silica (alumina) catalysts were prepared by co-impregnation. The catalysts were characterized with temperature programmed reduction and temperature programmed surface reaction techniques and hydrogenation of carbon monoxide. Thoria enhanced not only the activity but also the selectivity of olefins and long-chain hydrocarbons. Molybdena effectively promoted only the activity, but did not alter the product distribution pattern. Thoria and molybdena exhibited a tendency to spread onto and to interact intimately with alumina; the promoting effects on alumina were much less pronounced than on silica.

By self-consistently solving two-dimensional Schrodinger and Poisson equations, we have studied electron quantum wires formed by etching two shallow trenches in GaAs/InGaAs/AlGaAs and GaAs/AlGaAs heterostructures for single-electron-transistor applications. Two-dimensional electron gases (2DEGs) form in the InGaAs layer in GaAs/InGaAs/AlGaAs and at the GaAs/AlGaAs interface in GaAs/AlGaAs heterostructure, the two etched trenches deplete the carriers of the 2DEGs underneath and thus effectively define an electron quantum wire. It has been determined that two etched trenches with a depth of 50 nm and a spatial separation of 250 nm are optimal to create an electron quantum wire in a GaAs/InGaAs/AlGaAs heterostructure with a cross section of 80×10 nm2 and a peak electron concentration of 1.5×1018 cm−3 at 4.2 K.

A parallel dot structure, which is not conductively coupled but capacitively coupled, is fabricated. Both of the respective single dots show clear Coulomb blockade oscillations (CBOs) as their gate voltages are scanned. Single-electron charging in one dot causes oscillations of the current through another dot, even in the regime of more negative gate voltages where the CBOs cannot be observed due to a too weak current. In addition, information on the energy levels in one dot can be obtained.

BackgroundMacropinocytosis is an actin-driven endocytic process, whereby membrane ruffles fold back onto the plasma membrane to form large (>0.2 µm in diameter) endocytic organelles called macropinosomes. Relative to other endocytic pathways, little is known about the molecular mechanisms involved in macropinocytosis. Recently, members of the Sorting Nexin (SNX) family have been localized to the cell surface and early macropinosomes, and implicated in macropinosome formation. SNX-PX-BAR proteins form a subset of the SNX family and their lipid-binding (PX) and membrane-curvature sensing (BAR) domain architecture further implicates their functional involvement in macropinosome formation.Methodology/principal findingsWe exploited the tractability of macropinosomes through image-based screening and systematic overexpression of SNX-PX-BAR proteins to quantitate their effect on macropinosome formation. SNX1 (40.9+/-3.19 macropinosomes), SNX5 (36.99+/-4.48 macropinosomes), SNX9 (37.55+/-2.4 macropinosomes), SNX18 (88.2+/-8 macropinosomes), SNX33 (65.25+/-6.95 macropinosomes) all exhibited statistically significant (pConclusions/significanceSNX1, SNX5, SNX9, SNX18, and SNX33 were all found to elevate macropinosome formation and (with the exception of SNX33) associate with early-stage macropinosomes. Moreover the effects of SNX9 and SNX18 overexpression in elevating macropinocytosis is likely to be synergistic with the increase in PI(3,4,5)P(3) levels, which is known to accumulate on the cell surface and early-stage macropinocytic cups. Together these findings represent the first systematic functional study into the impact of the SNX-PX-BAR family on macropinocytosis.

The modified sol-gel processing technique of free casting provides an attractive route for preparation of low-shrink ceramic monoliths. Sols based on colloidal silica can be rapidly cooled and retain their frozen structure after warming to ambient temperatures. Owing to the large pore size in the gels, cracking is avoided during drying. A selection of silica sols has been examined and the state of aggregation of the particles was established as a critical parameter in determining whether sols can be processed in this way.

Subconjunctival fibrosis is one of the major causes of most bleb failures. To inhibit the wound-healing process and to achieve a better intraocular pressure (IOP) lowering effect as well as bleb formation, we performed a sclerostomy using a THC:YAG laser (thulium, holmium, and chromium-doped yttrium-aluminum-garnet crystal) and a subconjunctival injection of mitomy-cin-C given 24 h or 5 days before a filtering operation or soon after the filtering process in rabbits. A 1-mm conjunctiva wound was made 12 mm away from the sclerostomy site to allow for entry of an optic probe for delivering energy. Forty-eight rabbits were divided into four groups. Group I received a subconjunctival injection of 0.2 ml of 0.2 mg/ml of mitomycin-C 24 h before the operation. The same dosage of mitomycin-C was given to Group II 5 days before the operation and to Group III immediately following the operation. Group IV served as a control, and only 0.2 ml of normal saline solution was given 24 h preoperatively. One eye of each rabbit was randomly selected for the experiment, while the other eye served as a control. The bleb lasted 30.9 $pM 15.7 days in Group I, 16.0 $pM 6.4 days in Group II, 15.5 $pM 6.5 days in Group III, and 2.3 $pM 0.7 days in Group IV. The IOP lowering effect was parallel to bleb formation. The results demonstrate that a subconjunctival mitomycin-C injection given 24 h before a filtering operation is more effective in prolonging the filtering effect produced by the THC:YAG laser than one given postoperatively.

The ciliary muscle forms a major portion of the uveoscleral aqueous outflow pathway. To gain a better understanding of the extracellular matrix of the human ciliary muscle, human ciliary muscle cell cultures at various stages of confluency were immunocytochemically compared with sections of normal ciliary muscle for the presence of collagen types I, III, and IV, fibronectin, and laminin. A pre-embedding immunostaining protocol was employed to obtain good antigen conservation and histologically well-preserved tissue. In subconfluent cultured ciliary muscle cells, collagen types I, III, and IV, fibronectin, and laminin were found intracellularly in the endoplasmic reticulum or in granules surrounding the nucleus. In confluent cells, these matrix molecules each formed characteristic extracellular networks. In normal ciliary muscle, collagen type IV, fibronectin, and laminin were found in the basement membranes around the muscle fibers and blood vessels. Collagen types I and III and fibronectin were observed in the connective tissue among the muscle bundles. Collagen type I also formed a dense band of staining around blood vessels. The biosynthesis and turnover of these glycoproteins may have important roles both in the function of the nonconventional outflow pathway and in mediating the action of certain pharmacological agents.

To construct novel brewer's yeast strains with the ability to degrade beta-glucan and increase sulfite levels in beer brewing by genetic manipulation.The recombinant plasmid pA15ME containing P(met10)-egl1-T(met10) expression cassette was constructed. BamHI-linearized target plasmid pA15ME was transformed into the industrial brewer's yeast strain Z0103 to replace the MET10 locus through one-step gene replacement. The recombinants Z8, Z7 and Z3 with the ability to secrete active endo-beta-1,4-glucanase I into the culture medium were isolated by Congo red dyeing. The enzymatic activities of EG I of Z8, Z7 and Z3 were 3.3, 1.5, 1.3 U l(-1), and the hydrolysing degrees of beta-glucans in wort were increased 11.9%, 8.6% and 6.9%, respectively, than that of original strain Z0103. The MET10 gene deletions were confirmed by real-time PCR, and the sulfite levels of the culture mediums inoculated with Z8, Z7 and Z3 were increased 26%, 16% and 17%, respectively, compared to that of Z0103.The novel endoglucanase-producing brewer's yeast strains with inserted endoglucanase gene and deficient MET10 gene led to reduced content of barley beta-glucans, enhanced filterability and increased sulfur dioxide in fermenting wort. Thus, the cost for addition of microbial beta-glucanase enzyme and sulfite preparations in normal beer brewing processes could be reduced.These results suggested that genetic engineering approach is a powerful tool to construct the novel recombinant brewer's yeast strains with different properties to reduce the cost of beer brewing and improve the flavour of a beer, and the strains obtained have potential application value in beer brewing.

In this note, we give a simple and elementary proof of the following curious congruence which was established by Zhi-Wei Sun: \[ ∑ k = 1 ( p − 1 ) / 2 1 k ⋅ 2 k ≡ ∑ k = 1 [ 3 p / 4 ] ( − 1 ) k − 1 k ( m o d p ) . \sum ^{(p-1)/2}_{k=1}\frac {1}{k\cdot 2^k}\equiv \sum ^{[3p/4]}_{k=1} \frac {(-1)^{k-1}}{k}\quad (\mathrm {mod}\,p). \]

Objective: The use of surgical headlights may lead to awkward posture and limit the mobility and visibility of the operating team. Despite the vast availability of fiber-optic instruments, many surgeons continue to use the surgical headlight, which may be harmful to their health and career. We report the use of the Lumitex LightMat surgical illuminator instead of the conventional surgical headlight in cleft palate surgery. Methods: The LightMat is a disposable single-use device that is bright, flexible, and malleable and attaches easily to most retractors. Twenty cleft palate and five pharyngeal flaps cases were performed in which the LightMat was attached to the Dingman mouth retractor with biocompatible two-sided adhesive tapes. Results: The LightMat was successfully used in all 25 cases. No cases required the surgeon to put on additional lighting such as a headlight. In addition, no cases required the LightMat surgical illuminator to be replaced. Conclusion: The LightMat provides excellent surgical light for cleft palate surgery and pharyngeal procedures. It affords the surgeon several advantages: it provides a cool operative light, flexibility in surgical position, and improved visibility and mobility; the surgeon avoids the delay in obtaining an appropriate working headlight; and, more importantly, it may prevent postural problems that could lead to spinal sprain and disability.

Effects of a finite drain voltage and a finite temperature on coherent transport in the single electron tunneling regime are investigated for a novel quantum dot structure defined by two shallow etched trenches and two line Schottky gates. A regular amplitude modulation of Coulomb blockade oscillations is observed and attributed to coherent resonant transport. Increasing drain voltage disturbs the amplitude modulation more significantly than raising the temperature. This is explained in terms of the effects of nonmonochromatic electrons on the interference condition.

Aims: To construct a yeast one-hybrid system and isolate transcriptional activators. Methods and Results: A 1·1-kb promoter region of xylanase2 from Trichoderma reesei was cloned by PCR and sequenced (GenBank accession number: AY263380). Sequence analysis revealed that typical binding sites for several transcription factors in filamentous fungi, such as CREI, XLNR, ALCR, AREA and CCAAT enhancer, are located in the promoter. To isolate xyn2 transcription factors, the reporter plasmid of a yeast one-hybrid system was constructed on the backbone of the plasmid pRS415 containing the leu2 selective marker, with the xyn2 promoter region and Saccharomyces cerevisiaehis4 as a reporter gene. The reporter gene contained 123-bp minimal promoter region. The S. cerevisiae H158 strain containing the reporter plasmid was transformed with a T. reesei expression cDNA library, and 34 transformants were collected from SC-Leu-His-Ura plates. The isolation of the gene ace2 from several transformants showed that the one-hybrid system approach was successful. Then, approx. 59 mg l−1 of ace2 was overexpressed in Escherichia coli BL21. Significance and Impact of the Study: The yeast one-hybrid system is suitable for isolating transcription factors of filamentous fungi. ACE II is a main and universal transcriptional activator that controls cellulase and hemicellulase transcription regulation in T. reesei.

The ability to analyze a finite state machine (fsm) has always been desired by hardware designers, since an un-analyzed fsm is clearly prone to design bugs. Unfortunately there are too many ways to represent (code) an fsm. It is almost impossible for a tool to identify all possible fsm coding styles. In our department, at Cisco, we have a standardized fsm coding style. The standard fsm coding style allows us to easily extract an fsm. The extracted fsm is then fed to various tools for analysis: fsm reachability property, fsm coverage, and automatic fsm bubble diagram drawing. We show our standard fsm coding style, how fsms are extracted, and a well known algorithm that is used to study the reachability property. Then we show how to monitor the fsm transition coverage and also introduce a tool to automatically draw an fsm bubble diagram from the extracted fsm.

The effect of Fe-Ga pair defects on minority-carrier lifetime /spl tau/ in high-purity, dislocation-free float-zoned Si solar cells is presented, and their properties are documented by deep-level transient spectroscopy and annealing studies. The typical /spl tau/ of Fe-Ga co-doped crystals (0.4 /spl mu/s) was dramatically lower than /spl tau/ of crystals doped with similar amounts of either Fe alone (12 /spl mu/s) or Ga alone (1,400 /spl mu/s), contrary to the /spl tau/ behavior at low injection of Fe-B pair defects. Thermal dissociation of Fe-Ga pairs increased /spl tau/, confirming a stronger carrier-recombination activity at Fe-Ga pairs than at interstitial Fe. Defect energies (relative to the valance band) equal to 0.10 and 0.21 eV were observed for Fe-Ga co-doped samples, and the corresponding hole-capture cross sections (at T=/spl infin/) were 3/spl times/10/sup -16/ and 6/spl times/10/sup -15/ cm/sup 2/. An estimation of the binding energies resulted in much lower values than expected (0.09 eV and 0.15 eV, respectively).

In the present study, the effect of endothelin-1 (ET-1) on the expression of proto-oncogene c-fos in cultured neonatal rat myocardial cells was investigated. The results are as follows: ET-1 induced c-fos expression in a dose-dependent manner. Selective ET(A) receptor antagonist blocked ET-1-induced responses. Protein kinase C(PKC) agonist PMA induced c-fos expression.PKC inhibitor staurosporine blocked ET-1 induced c-fos expression. Calcium channel blocker, nifedipine did not significantly affect the expression of c-fos induced by ET-1. These results suggest that in cultured neonatal cardiomyocytes, ET-1 induced c-fos gene expression is mediated by ET(A) receptor with the participation of protein kinase C, while the voltage-dependent L-type Ca(2+) channel is not involved.

Bovine aortic endothelial cells (BAECs) were used to study the effect of 17beta -estradiol (E(2)) on nitric oxide (NO) release, nitric oxide synthase (eNOS) mRNA expression and intracellular free calcium con~cen~tration ([Ca(2+)](I)) and modulation of the effect of E(2) by estrogen receptor (ER) antagonist tamoxifen and NOS inhibitor L-NAME. E(2) (10(-12) 10(-8) mol/L) induced NO release of BAECs in a concentration-dependent manner and the abundant expression of eNOS mRNA in BAECs increased obviously after treatment with E(2) (10(-8)mol/L) for 48 h. These effects were evidently inhibited by tamoxifen (10(-7)mol/L) and L-NAME (10(-6) mol/L). Furthermore treatment with E(2) (10(-8) mol/L) for 48 h significantly increased the resting [Ca(2+)](I) and the rise of [Ca(2+)](I) induced by ATP in BAECs. These results suggest that E(2)-induced NO release and eNOS mRNA expression in BAECs may be mediated by ER and related to calcium mobilization.

The aim of this study was to determine the regulation by MKP-1 of MAPK activity and protein expression in cardiomyocyte hypertrophic response induced by Ang II. Neonatal rat cardiomyocyte hypertrophic response was assayed by cell surface area, protein synthesis rate and protein content. MAPK activity was determined by an in-gel kinase assay. Protein expression of MAPK and MKP-1 were detected by Western blotting. The results are as follows. (1) Ang II induced promotion of (3)H-leucine incorporation and increase in cell protein content and cell surface area in a dose-dependent manner. Pretreatment with a selective AT(1) receptor antagonist CV11974 or a specific MEK inhibitor PD098059, cardiomyocyte hypertrophic response induced by Ang II was inhibited by 85% and 32.5%, respectively. (2) After pretreatment with PD098059 or CV11974, AngII-induced increases in p44MAPK and p42MAPK protein expression and enzyme activity (expressed by gamma-(32)P-ATP incorporation) were all inhibited obviously. (3) With treatment of myocytes by Ang II for 5 min, MAPK activity determined by p44MAPK and p42MAPK protein expression began to increase, while MKP-1 protein expression was detected within 30 min and lasted more than 2 h following treatment with Ang II. (4) Pretreatment of cardiomyocytes with actinomycin D (3 microgram/ml) for 30 min inhibited MKP-1 protein expression, while p44MAPK and p42MAPK protein expression was still detected 120 min after Ang II treatment. The above results demonstrate that activation of MAPK plays an important role in Ang II-induced cardiomyocyte hypertrophic response in neonatal rat cardiomyocytes through MKP-1 mediated inactivation of p44MAPK and p42MAPK.cardiomyocyte hypertrophic response in neonatal rat cardiomyocytes through MKP-1 mediated inactivation of p44MAPK and p42MAPK.

In the present study, the effects of 17 beta-estradiol on vascular reactivity of ovariectomized rats and proliferation of cultured rat aortic smooth muscle cells were studied. The vascular reactivity was significantly increased in ovariectomized rats compared with the sham-operated animals. The selective ETA receptor antagonist BQ123 inhibited the increase in [3H]-TdR incorporation in response to ET-1 on vascular smooth muscle cells (VSMCs). 17 beta-estradiol also attenuated the ET-1 effects in a dose-dependent manner. The results of RT-PCR and Western blot show that expression of ETA receptor was decreased after treatment with 17 beta-estradiol. The effect of 17 beta-estradiol was partially inhibited by estrogen receptor antagonist tamoxifen. The above results demonstrate that proliferation of VSMCs stimulated by ET-1 was mainly mediated through ETA receptor. Due to the down-regulation of ETA receptor and mediation of estrogen receptor, 17 beta-estradiol inhibits the ET-1-induced proliferation of VSMCs and decreases the vascular reactivity of ovariectomized rats.

To suppress turbulent flow in a large silicon melt, Drs. Ciszek and Wang at NREL have proposed and patented a new Czochralski (CZ) growth furnace that has a shallow melt. To supply silicon to a shallow melt for long ingot growth, a crucible with partitions has been designed which allows continuous growth of a crystal by feeding silicon pellets into a dedicated compartment of the crucible. In this paper, temperature distributions in the entire furnace are simulated for the new system in a simplified manner as the first step to compare with those more sophisticated simulation results on a conventional CZ growth system. The effects of power level of individual heaters on temperature distribution in the melt are discussed. The simulation results show that a favorable temperature distribution can be obtained in the new furnace through changing the power ratio of the side and bottom heaters.Copyright © 2002 by ASME

We have investigated photoluminescence of double‐barrier diodes under various bias voltages and observed the saturation of the broadening of the photoluminescence lines. We have also studied the integrated photoluminescence intensity with increasing applied voltages near resonant voltages for high quality samples at low temperature (4.2 K). The results of the 77 K photoluminescence experiments confirm those at 4.2 K. The saturation of the broadening is due to weak hole localization; however, the saturation of the integrated photoluminescence intensity is mainly due to reduced nonradiative recombination. Our results suggest that the hole localization may arise from interface roughness.

Infection of microglia and other cells of the macrophage/monocyte lineage in the central nervous system (CNS) by human immunodeficiency virus type I (HIV-1) underlies the development of giant cell encephalitis (GCE). It is currently unknown whether GCE depends on the emergence of virus populations specifically adapted to replicate in cells of the monocyte/macrophage lineage and whether this also leads to the specific targeting of macrophages in other nonlymphoid tissues. Autopsy samples from lymph node, brain (frontal region), lung, and full-thickness colon sections were obtained from nine study subjects with GCE and from nine without. The two groups showed no significant differences in CD4 counts, disease progression, or treatment history before death. Genetic relatedness between variants recovered from lymph node and nonlymphoid tissues was assessed by sequence comparison of V3 and p17gagregions using a newly developed method that scores the sample composition at successive nodes in a neighbor-joining tree. The association index enabled objective, numerical comparisons on the degree of tissue compartmentalization to be made. High proviral loads and p24 antigen expression in the brain were confined to the nine individuals with GCE. GCE was also associated with significantly higher proviral loads in colon samples (median of the GCE+group: 1,010 copies/106cells; median of GCE−group, 10/106cells;P= 0.006). In contrast, there were no significant differences in proviral load between the GCE+and GCE−groups in lymph node or lung samples, where HIV infection was manifested predominantly by infiltrates of lymphoid cells. V3 sequences from brain samples of individuals with GCE showed the greatest compartmentalization from those of lymph node, although samples from other tissues, particularly the colon, frequently contained variants phylogenetically related to those found in brain. The existence of shared, distinct populations of HIV specifically distributed in cells of the monocyte/macrophage lineage was further indicated by immunocytochemical detection of CD68+, multinucleated giant cells expressing p24 antigen in samples of lung and colon in two individuals with GCE. This study provides the basis for future investigation of possible phenotypic similarities that underline the shared distributions of HIV variants infecting microglia and tissue macrophages outside the CNS.