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This discussion of intelligent tutoring systems (ITS) focuses on a description of C-Tutor, a knowledge-based ITS for novice C programmers. The program analyzer, which is a compound of a reverse engineering system and a didactic system, is explained, and implementation and evaluation is discussed. (LRW)

Global warming-induced changes in the pattern and amount of precipitation are important from the viewpoint of long-term stability of geo-structures. In this paper, the effectiveness of in-plane drainage provided by permeable geosynthetic reinforcement was evaluated as a means to relieve the rainfall infiltration effect on GRS walls backfilled with marginal soil. A series of laboratory tests were performed using a reduced-scale model geosynthetic reinforced soil (GRS) wall (constructed with due consideration of the similitude law) with different rainfall characteristics and backfill soils. Layers of nonwoven geotextiles were used as reinforcement as well as in-plane drainage media. The results showed that the inclusion of internal drainage facilitated the dissipation of pore water pressure, thereby reducing the wall facing displacement. The discharge water volume and volumetric water content data measured in the reinforced soil zone supported the observation. The degree to which the internal drainage improves the deformation behavior of the GRS wall during rainfall was found to depend on the rainfall characteristics and the backfill soil type. Practical implications of the findings are discussed in detail. [ABSTRACT FROM AUTHOR]

The radioactive aerosol generated by the Nuclear Power Plant (NPP) decommissioning process can be inhaled by workers and deposited inside the human body, resulting in internal exposure. Because internal exposure, unlike external exposure, is difficult to measure directly, it is all the more necessary to assess the dose workers receive as a result of internal exposure. Precise assessment of the internal exposure necessitates actual measurements in the work environment such as the workers' respiration rate, kind of nuclide and amount of captured nuclide. However, in the event of difficulties in securing these measurements, the internal exposure dose can be estimated based upon the recommended values by the ICRP (International Commission on Radiological Protection) such as the intake fraction and particle size. In this study, 5 μm was selected as the particle size as recommended by the ICRP, and both heavy and light respiratory rates were used in the calculation. With respect to the nuclides contained in the radioactive aerosol and their concentrations, the data captured for the aerosol in the melting facility on the Kozloduy NPP premises in Bulgaria were applied to estimate workers' internal exposure. As a result, each worker was found not to have received more than 20 mSv/yr, which is the maximum annual permissible dose for workers. [ABSTRACT FROM AUTHOR]

Using deep-level-transient spectroscopy, we have investigated deep levels in heavily Al-doped ZnSe layers grown by molecular-beam epitaxy. The Al concentration of the ZnSe layers lies in the range of 5×1018–9×1018 cm-3. The ZnSe:Al layers exhibit two electron-trap centers with the thermal activation energies of 0.16 eV (ND1) and 0.80 eV (ND2). ND2 is a dominant trap center with a trap density of 3×1016 cm-3, while the trap density of ND1 is estimated to be 2×1015 cm-3. However, ND2 shows anomalous behaviors, different from isolated point defects, in the following points: (1) the emission peak of ND2 moves to the low temperature side with increasing filling pulse duration; (2) the emission peak of ND2 is broader than theoretically calculated one for an isolated point defect; and (3) the capacitance-transient curve is nonexponential. It is observed by high-resolution x-ray diffraction that heavy Al doping results in the relaxation and plastic deformation of the ZnSe lattice. These behaviors can be ascribed to extended defects with a broad energy spectrum. By assuming a Gaussian distribution of deep levels due to extended defect, the broad emission peak is successfully simulated. [ABSTRACT FROM AUTHOR]

The structure, magnetic properties, and magnetostriction of Sm[sub 0.5]R[sub 0.5](Fe[sub 1-x]Co[sub x])[sub 2] compounds (R = Nd, Pr) have been investigated by using x-ray diffraction analysis, ac initial susceptibility, vibrating sample magnetometer, and standard strain techniques. It was found that the (Sm[sub 0.5]Nd[sub 0.5])Fe[sub 2] compound with MgCu[sub 2]-type cubic structure possesses low magnetocrystalline anisotropy and high ratio of magnetostriction to magnetocrystalline anisotropy. When Co is substituted for Fe, the Curie temperature of (Sm[sub 0.5]Nd[sub 0.5])(Fe[sub 1-x]Co[sub x])[sub 2] alloys exhibit a peak at x = 0.25 and the saturation magnetization increases with increasing Co content when x<0.25 and decreases when x≥0.5. The microstructure of (Sm[sub 0.5]Pr[sub 0.5])(Fe[sub 1-x]Co[sub x])[sub 2] alloys is nearly a single phase in the range of 0.75≤x≤1. The saturation magnetization and magnetostrictiom of the alloys exhibit a peak at x = 0.25 and x = 0.5, respectively. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the sixth most common malignancy worldwide and the leading cause of death in Asian and African countries. Aberrant accumulation of lncRNAs is one of the major causes of tumorigenesis in HCC. Small nucleolar RNA host gene 16 (SNHG16) is identified as an oncogene in multiple types of tumors. However, the role of SNHG16 in HCC is poorly understood. Herein, we show that SNHG16 is up-regulated and associated with poor prognosis in HCC. We also demonstrate that SNHG16 interacts with miR-302a-3p and decreases its expression. Moreover, our results indicate that SNHG16/miR-302a-3p axis regulates expression of the FGF19 in liver cancer cells. Finally, we investigated the biological function of SNHG16 in HCC and showed that SNHG16 promotes liver cancer cell proliferation via the SNHG16/ miR-302a-3p/FGF19 axis. Collectively, these data suggest that SNHG16 might be a predictive biomarker and a potential therapeutic target in liver cancer. [ABSTRACT FROM AUTHOR]

Presents a model for the photovoltaic effect of the grain boundary caused by a scanning laser beams. Features of the model; Background on theoretical assumptions in developing the model; Significance of grain boundaries to semiconductors.

Presents a study that investigated the magnetic properties of an iron-base amorphous alloy which contains additional insoluble silver. Measurement of the saturation magnetization of the sample; Determination of the coercive force; Analysis of the electrical resistivity of the samples.

The goal of the present paper is to investigate the phase stability and soft magnetic properties of amorphous CoNbZr films when Pd is added. The CoNbZrPd films deposited on Si wafers exhibited amorphous structures independent of the amount of Pd. On the addition of 4.34% Pd, excellent soft magnetic characteristics of the films were observed with a coercive force of 0.54 Oe and an anisotropy field of 11 Oe, whereas a coercive force of 1 Oe and an anisotropy field of 3.5 Oe were shown in the film without the addition of Pd. The increased anisotropy field and low coercive force of the films may be attributed to the occupancy of Pd in preferred sites parallel to an external magnetic field applied during the deposition process. A permeability of about 1100 was constant at operation frequencies ranging up to 100 MHz, which can be explained by the Landau-Lifshitz formula. [ABSTRACT FROM AUTHOR]

Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To investigate whether serum leucine-rich α2-glycoprotein (LRG) levels are elevated in patients with adult-onset Still's disease (AOSD) and determine their correlation with disease activity parameters.Method: We enrolled 39 patients with AOSD, 47 patients with rheumatoid arthritis (RA), and 39 controls. Forty-five serum samples from the patients with AOSD were assayed for LRG using an enzyme-linked immunosorbent assay (ELISA). Comprehensive AOSD activity was determined by a modified Pouchot score.Results: Serum LRG levels were significantly elevated in patients with AOSD (128.8±40.8 ng/mL) compared to those in patients with RA and in controls (33.9±15.2 ng/mL, p<0.001 and 22.4±6.1 ng/mL, p<0.001, respectively). Patients with active AOSD had significantly higher LRG levels than those with inactive disease (141.4±31.3 ng/mL vs. 79.8±37.1 ng/mL, p=0.002). Serum LRG levels were positively correlated with C-reactive protein (CRP; γ=0.387, p=0.015), lactate dehydrogenase (LDH; γ=0.370, p=0.026), ferritin (γ=0.687, p<0.001) levels, and the modified Pouchot score (γ=0.756, p<0.001). Serum LRG levels decreased significantly after treatment in all six patients with active AOSD who had follow-up evaluations (p=0.007). The best cut-off value for LRG to distinguish AOSD from RA was 67.9 ng/mL, with a sensitivity of 92.3% and a specificity of 97.9%.Conclusions: Serum LRG levels were increased in patients with AOSD and correlated well with disease activity measures. LRG may be a useful biomarker for distinguishing AOSD from RA and for monitoring the disease activity of AOSD. [ABSTRACT FROM AUTHOR]

The effects of herbicide dose on rice-weed competition were investigated to develop a combined model, which can be utilised to estimate an optimum herbicide dose for a given weed density in paddy rice cultivation. Field studies were conducted in Suwon for rice- Echinochloa crus-galli competition and Iksan for rice- Eleocharis kuroguwai during 2007. The competitive effect of the weeds E. crus-galli and E. kuroguwai decreased with increasing doses of flucetosulfuron and azimsulfuron, respectively, in the same manner as the standard dose-response curve. The combination of the rectangular hyperbolic model and the standard dose-response curve adequately described the complex effects of herbicide dose and weed competition on rice yield. Parameter estimates were used with the model to predict rice yield and estimate the doses of flucetosulfuron and azimsulfuron required to restrict rice yield loss caused by E. crus-galli and E. kuroguwai, respectively, to an acceptable level. For a rice yield of 5.0 t ha−1, the model recommended flucetosulfuron doses of 8.7, 13.4 and 20.1 g a.i. ha−1 when infested with E. crus-galli at 12, 24 and 48 plants m−2 respectively. For a rice yield of 5.2 t ha−1, the model recommended azimsulfuron doses of 3.9, 7.5 and 12.6 g a.i. ha−1 when infested with E. kuroguwai at 24, 48 and 96 plants m−2 respectively. The theoretical outputs of the combined model appear robust and indicate there are opportunities for reduced herbicide use in the field. These now require evaluation under field conditions. [ABSTRACT FROM AUTHOR]

This study proposes a method to produce biodiesel from wet wastewater sludge. Xylene was used as an alternative cosolvent to hexane for transesterification in order to enhance the biodiesel yield from wet wastewater sludge. The water present in the sludge could be separated during transesterification by employing xylene, which has a higher boiling point than water. Xylene enhanced the biodiesel yield up to 8.12%, which was 2.5 times higher than hexane. It was comparable to the maximum biodiesel yield of 9.68% obtained from dried sludge. Xylene could reduce either the reaction time or methanol consumption, when compared to hexane for a similar yield. The fatty acid methyl esters (FAMEs) content of the biodiesel increased approximately two fold by changing the cosolvent from hexane to xylene. The transesterification method using xylene as a cosolvent can be applied effectively and economically for biodiesel recovery from wet wastewater sludge without drying process. [ABSTRACT FROM AUTHOR]

The Bi0.85Eu0.15FeO3/Bi3.2Y0.8Ti3O12 bilayer thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates using the sol-gel process and annealed by rapid thermal annealing in various annealing environments (ambient atmosphere and oxygen). The multiferroic/ferroelectric bilayer thin films were composed of 0.8-\mum thickness Bi0.85Eu0.15FeO3 and 0.2-\mum thickness of Bi3.2Y0.8Ti3O12 thin film. The effects of annealing atmospheres (ambient atmosphere and oxygen) on the growth and properties of thin films were investigated. The results show that the intensities of the (117) diffraction peak of Bi3.2Y0.8Ti3O12 film and (110) diffraction peak of Bi0.85Eu0.15FeO3 annealed in oxygen is stronger than those annealed in an ambient atmosphere. The Bi0.85Eu0.15FeO3/Bi3.2Y0.8Ti3O12 bilayer thin films annealed in the oxygen atmosphere exhibit the maximum remanent polarization (2\mbi Pr) and remnant magnetization (2Mr) of 26 \muC/cm^2 and 3.44 emu/g, respectively. The improved magnetic and ferroelectric properties can be attributed to the elimination of defects, such as oxygen vacancy and vacancy complexes. [ABSTRACT FROM AUTHOR]