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It is important to determine the anterior capsular zonular free zone (ZFZ) in order to minimize the risk of zonular disinsertion. From this point of view the size of the ZFZ of normal suspended lenses was directly measured in 199 human eyes obtained postmortem. The cornea was completely excised and the iris removed to allow clear visualization of the anterior surface of the lens to the equator. After measuring lens diameter with a caliper, a 4 mm continuous curvilinear capsulorhexis was performed, and lens substrate was completely removed by phacoemulsification. Care was taken to minimize trauma to the zonules during surgery. The anterior insertion of the zonules was identified at high power magnification; the size of the ZFZ was measured with a caliper. The mean age was 75.5 +/- 10.3 (+/-SD) years (age range, 50 approximately 100 years). The mean diameter of the lenses was 9.72 +/- 0.31 mm. The mean diameter of the ZFZ was 6.83 +/- 0.35 mm. Statistical analysis revealed no significant correlation between the size of the ZFZ and age, or between the size of the ZFZ and lens diameter. The present study indicates that the size of the ZFZ was constant regardless of age or lens diameter.

Protein kinase C (PKC) plays an important role in activation of human immunodeficiency virus type 1 (HIV-1). Because of a molecular and biochemical heterogeneity of PKC, we have studied the effects of PKC isozymes in HIV-1 activation in a latently infected promonocytic cell line, U1, using various PKC isozyme agonists. 12-Deoxyphorbol 13-phenylacetate (dPP), an agonist of both Ca(++)-dependent and Ca(++)-independent isozymes, and thymeleatoxin (TT), an agonist of Ca(++)-dependent PKC isozymes, induced HIV-1 production at 10 nM with increase in a concentration dependent manner, whereas 12-deoxyphorbol 13-phenylacetate 20-acetate (dPPA), an PKC beta I isozyme agonist, did not induce viral production at 100 nM. We verified that dPPA induced translocation of PKC beta isozyme with the isozyme-specific monoclonal antibody using flow cytometry. This study demonstrates that activation of PKC isozymes leads to an induction of latent HIV-1 in U1 cells whereas PKC beta I isozyme may not be important.

ZnO:N flexible thin film transistors were fabricated by atomic layer deposition on polyethylene naphthalate substrates and the effects of bending on the device properties investigated. The threshold voltage and saturation mobility were observed to change with respect to the amount of substrate bending. These modulations can be explained in terms of piezoelectric nature of in ZnO. In comparison with the previously reported single crystal nanowires ZnO field effect transistors, the amount of the electrical property modulation under bent condition is significantly reduced and our report shows a much improved stability for ZnO:N as a flexible device material.

464 Background: We investigated the expression of beclin-1 and bcl-2 in human colon cancer tissue by immunohistochemical analysis using a tissue microarray in relation to other prognostic factors. Methods: Tissue samples from 78 cases of invasive colon cancer were used for the present study. A positive control for bcl-2 expression was small lymphocytes in the mantle zone. Immunohistochemical staining for beclin-1 and bcl-2 was evaluated according to intensity and proportion. The intensity score was determined as 0 (no staining), 1 (weak), 2 (moderate) and 3 (strong). The proportion score was determined as 1 (< 30% of tumor cells) and 2 (≥ 30% of tumor cells). The intensity score and proportion score were multiplied together for a total score. Total scores were as follows: 0-1 (negative) and 2-6 (positive). Results: The normal colonic epithelium showed weak to no beclin-1 expression. Positive beclin-1 expression and positive bcl-2 expression of colon cancer cells was observed in 48 cases (61.5%) and 10 cases (12.8%), respectively. beclin-1 expression was significantly correlated with lymph node metastasis (p = 0.035) Bcl-2 expression in colon cancer cells showed no significant correlation with clinocopathologic factors studied. Beclin-1 expression was not correlated with bcl-2 expression in colon cancer cells (p = 0.348). Conclusions: In conclusion, we have characterized the expression of beclin-1 in human colon cancer and the relationship with bcl-2 protein. Our results suggest that it seems reasonable to assume that beclin-1 might play a role in the development of colorectal cancer. No significant financial relationships to disclose.

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Titanium oxide (TiO2) layer was used to control the flatband voltage (VFB) of p-type metal-oxide-semiconductor field effect transistors. TiO2 was deposited by plasma enhanced atomic layer deposition (PE-ALD) on hafnium oxide (HfO2) gate dielectrics. Comparative studies between TiO2 and Al2O3 as capping layer have shown that improved device properties with lower capacitance equivalent thickness (CET), interface state density (Dit), and flatband voltage (VFB) shift were achieved by PE-ALD TiO2 capping layer.

We investigated the effects of UV treatment on the device properties of a plasma-enhanced atomic layer deposition (PE-ALD) ZnO thin film transistor (TFT). Remote PE-ALD ZnO thin films were used as active layers for bottom-gate TFT devices. The as-deposited PE-ALD ZnO film at a growth temperature of 200°C has an overly small carrier concentration, which produces a TFT device with no modulation by gate voltage sweep. However, after UV light exposure, the device shows proper TFT modulation by gate voltage. The threshold voltage (V th ) of the device can be controlled to the negative direction by increasing the UV exposure time. V th moves from 17.8 to -6.5 V with an increase in UV exposure time from 3 to 120 min.

The electrical properties of atomic layer deposition (ALD) nitrogen-doped ZnO (ZnO:N) thin films were investigated as a function of incorporated nitrogen concentration. The nitrogen concentrations in the films were controlled by using different concentrations of NH 4 0H solution, which was used as a single source for the reactant and nitrogen doping for ALD ZnO:N. The carrier concentrations in ALD ZnO:N decreased down to 6.13 × 10 13 /cm 3 using 29% NH 4 OH solution. Thin film transistors (TFTs) were fabricated using ALD ZnO:N thin films with different N contents as active channel layers. The device properties were significantly changed by the amount of nitrogen incorporation due to the change in the electrical properties of ZnO:N films. Especially, threshold voltages were changed from 20.0 to 3.1 V by adjusting nitrogen doping. Additionally, dc bias stability was enhanced by the increment in nitrogen concentration, producing a robust TFT at high nitrogen incorporation. Finally, a high performance flexible TFT was fabricated using ALD ZnO:N as an active layer on poly(ethylene naphthalate) substrate.

Atomic layer deposition (ALD) is a promising deposition technique for nanoscale device fabrication due to its great benefits including excellent conformality, atomic scale thickness control, high quality deposition at low growth temperature, and large area uniformity. In this presentation, we will present a couple of examples for novel applications of ALD; metallic nanomaterial fabrications combined by nanotemplate utilizing the excellent conformality of ALD and fabrication of driving devices for transparent flexible displays utilizing the ability of ALD to produce high quality materials at low growth temperature. These examples manifest the benefits of ALD in the near future industry.

High performance thin film transistor (TFT) with atomic layer deposition (ALD) nitrogen doped ZnO (ZnO:N) as an active layer is demonstrated. The electrical properties of ZnO thin films were effectively controlled by in situ nitrogen doping using NH4OH as a source for reactants. Especially, the electron concentration in ZnO was lowered to below 1015cm−3. Good device characteristics were obtained from the inverted staggered type TFTs with ZnO:N channel and ALD Al2O3 gate insulator; μsat=6.7cm2∕Vs, Ioff=2.03×10−12A, Ion∕off=9.46×107, and subthreshold swing=0.67V∕decade. The entire TFT fabrication processes were carried out at below 150°C, which is a favorable process for plastic based flexible display.

Atomic layer deposition (ALD) process for oxynitrides of high-k gate dielectrics employing NH4OH as a single source for reactants, water and NH3, was studied. By this method, nitrogen was incorporated up to 1–3at.% for ALD Al2O3 and Ta2O5 films from metal organic precursors. A comparative study with water based ALD showed that the electrical properties were improved. The leakage current of oxide films from NH4OH based ALD had been reduced and, more importantly, the dielectric strength was found to be enhanced by more than two orders of magnitude from a time dependent dielectric breakdown measurement.

We report a high power fundamental transverse mode operation of an optically pumped 1060nm vertical-external-cavity surface-emitting laser. A diamond heat spreader was capillary bonded to the semiconductor surface. A 10W continuous wave operation with optical-to-optical conversion efficiency of 44% was achieved at room temperature. The thermal rollover was not found up to a heat sink temperature of 60°C. High efficiency and good thermal stability were mainly due to the optimization of epitaxial quality and the high conductivity of the diamond heat spreader. We have found that the increase of the round trip loss caused by the heat spreader was about 1%.

A ductile fracture criterion is newly proposed to model fracture behavior of sheet metals for nucleation, growth and shear coalescence of voids during plastic deformation. In the new ductile fracture criterion, void nucleation is described as a function of the equivalent plastic strain, void growth is a function of the stress triaxiality and void coalescence is controlled by the normalized maximal shear stress. The new ductile fracture criterion is applied to construct a fracture forming limit diagram (FFLD) of a dual phase steel sheets of DP780 (1.0t). The FFLD is approximated using both the reverse engineering method and circle grid analysis (CGA) since DP780 fails with slight thickness reduction from the analysis of the fracture surface. Predicted FFLDs are compared to experimental results to validate the performance of the new criterion in the intermediate stress triaxiality between 1/3 and 2/3. The new criterion is also applied to construct the fracture locus of Al 2024-T351 ( Bao and Wierzbicki, 2004 ) to validate the performance of the new criterion in the low and negative stress triaxiality. The fracture locus constructed by the new criterion are close to the experimental data points for all these two materials in a wide stress range from the uniaxial compression to the balanced biaxial tension. The new ductile fracture criterion is recommended to be utilized in finite element analysis to predict the onset of ductile fracture of sheet metals.

The construction of dams across the mouths of major tidal rivers in the development of the Kranji Reservoir, Western Catchments Scheme and the Sungei Seletar Reservoir in Singapore created suitable environmental conditions for the propagation of anopheline brackish-water breeders. The employment of foreign contract workers from malarious areas for the projects further increased the potential risk of malaria transmission. However, constant vigilance and environmental management aimed at the permanent elimination of vector breeding habitats, supplemented with chemical control and anti-parasite measures successfully prevented the reintroduction of malaria in these highly receptive and vulnerable areas.

A nation-wide outbreak of 260 cases of DF/DHF with 1 death occurred in Singapore from Apr-Sept 1986. The outbreak originated from 3 separate foci of transmission at the western, south-eastern and north-eastern parts of the island and then spread to other dengue receptive urban and suburban areas. The morbidity rate was highest in young male Chinese adults between 15 and 24 years of age. The outbreak was rapidly brought under control through destruction of adult Aedes mosquitoes, surveys and source reduction of larval breeding habitats, health education and to a certain extent law enforcement. The Aedes population was high in the main foci of transmission although the overall house index was only 1.1. Other factors which could have precipitated the outbreak included waning herd immunity of the human population and continuous introduction of dengue virus into the country.

The conventional brick handling such as road paving site, building construction site is allocated to the construction workers. Since these kinds of tasks are obviously labor-intensive and tedious, there have been many approaches to the automation at the construction site. However, the automation of the block-laying task still has several problems caused by the poor surroundings - inequable construction materials and uneven working conditions like various laying and paving patterns. Herein, this paper proposes an integrated mobile manipulator system operated by the optimal laying pattern and trajectory generation algorithm. The pattern generator is designed by the “Fast Algorithm” based on Steudel’s algorithm; the trajectory generation algorithm is based on the “Overlap Method” which is a treatment skill for robot-surrounded obstacles. This study mainly shows the efficiencies of the proposed pattern and trajectory generation algorithm for the brick-laying task and the performance evaluation of the prototype system.