Automating the tracking of lymph nodes in follow-up studies of thoracic CT images

The study of lymph node features over time is of great clinical significance. Tracking of the same lymph node in CT images over time is done manually in the current clinical practice, which is tedious and lack of consistency. In this paper, we propose a search scheme to automate the process. Regions of interest (ROIs) are located by mapping the center point of lymph node based on the transformation found in the rigid registration. Similarity values between ROI of the template image and ROIs of repository images are compared, the highest of which decides the best match. Our method generated a success rate of 82% in determining the corresponding image in follow-up scan with the same lymph node as in baseline. The location of the lymph node in the corresponding image is tracked and estimated by mapping the lymph node center at baseline image using the transformation obtained from both affine and free-form deformation (FFD) registration. FFD performs better than affine registration in tracking the lymph node location. All lymph nodes in our study are tracked successfully by the suggested points which fall within the boundary of the same node in the corresponding follow-up images using FFD registration.     

Phase Engineering of 2D Tin Sulfides

Tin sulfides can exist in a variety of phases and polytypes due to the different oxidation states of Sn. A subset of these phases and polytypes take the form of layered 2D structures that give rise to a wide host of electronic and optical properties. Hence, achieving control over the phase, polytype, and thickness of tin sulfides is necessary to utilize this wide range of properties exhibited by the compound. This study reports on phase‐selective growth of both hexagonal tin (IV) sulfide SnS₂ and orthorhombic tin (II) sulfide SnS crystals with diameters of over tens of microns on SiO₂ substrates through atmospheric pressure vapor‐phase method in a conventional horizontal quartz tube furnace with SnO₂ and S powders as the source materials. Detailed characterization of each phase of tin sulfide crystals is performed using various microscopy and spectroscopy methods, and the results are corroborated by ab initio density functional theory calculations.     

Multi-level adaptive simulation of transient two-phase flow in heterogeneous porous media

An implicit pressure and explicit saturation (IMPES) finite element method (FEM) incorporating a multi-level shock-type adaptive refinement technique is presented and applied to investigate transient two-phase flow in porous media. Local adaptive mesh refinement is implemented seamlessly with state-of-the-art artificial diffusion stabilization allowing simulations that achieve both high resolution and high accuracy. Two benchmark problems, modelling a single crack and a random porous medium, are used to demonstrate the robustness of the method and illustrate the capabilities of the adaptive refinement technique in resolving the saturation field and the complex interaction (transport phenomena) between two fluids in heterogeneous media.     

A multi-modal immune algorithm for the job-shop scheduling problem

This paper describes the application of an artificial immune system to a scheduling application. A novel approach multi-modal immune algorithm is proposed for finding optimal solutions to job-shop scheduling problems emulating the features of a biological immune system. Inter-relationships within the proposed algorithm resemble antibody molecule structure, antibody-antigen relationships in terms of specificity, clonal proliferation, germinal center, and the memory characteristics of adaptive immune responses. Gene fragment recombination and several antibody diversification schemes including somatic recombination, somatic mutation, gene conversion, gene reversion, gene drift, and nucleotide addition were incorporated into the algorithm in order to improve the balance between exploitation and exploration. In addition, niche antibody was employed to discover multi-modal solutions. Numerous well-studied benchmark examples in job-shop scheduling problems were utilized to evaluate the proposed approach. The results indicate the effectiveness and flexibility of the immune algorithm.     

One-dimensional germanium nanostructures--formation and their electron field emission properties

Ge nanostructures were synthesized by reduction of GeO(2) in H(2) atmosphere at various temperatures. Entangled and straight Ge nanowires with oxide shells were grown at high temperatures. Ge nanowires with various numbers of nodules were obtained at low temperatures. Ge nanowires without nodules exhibited remarkable field emission properties with a turn-on field of 4.6 V μm(-1) and field enhancement factor of 1242.     

Transdermal Nicotine Delivery Systems: Multi-institutional Cooperative Bioequivalence Studies

Nicotine transdermal delivery systems (nicotine-TDSs) have been evaluated clinically and found to provide effective assistance to smokers in smoking cessation with minimal occurrence of withdrawal symptoms. However, substantial skin reactions have been reported with the four nicotine-TDSs marketed recently. To reduce the skin reactions, a new type of nicotine-TDS has been recently developed. In vitro skin permeation studies demonstrated that this nicotine-TDS yields a constant skin permeation profile with a rate of permeation across the human cadaver skin comparable to the steady-state permeation rates attained by Habitrol™ and Nicoderm® systems. Clinical studies completed in two ethnic groups have demonstrated that this newly-developed nicotine-TDS is clinically effective and has yielded minimal skin irritation. As part of technical transfer program, a clinical study was initiated in 18 non-obese non-smoking Taiwanese, using Latin-square design, to compare the systemic bioavailability and pharmacokinetic profile of nicotine delivered transdermally from the nicotine-TDSs fabricated at technology licensee (Sintong nicotine-TDS) in comparison with that from the technology developer (TBS nicotine-TDS), using one marketed nicotine-TDS (Habitrol™ system) as the reference product. In vitro release and skin permeation studies of nicotine from the nicotine-TDSs manufactured at both licensor and licensee were found similar in kinetic profiles and comparable in rates. Since the patch size of these nicotine-TDSs studied was smaller than the marketed product used (10 cm² for both Sintong and TBS nicotine-TDSs, versus 20 cm² for Habitrol™ system), the daily doses of nicotine delivered to the volunteers are equivalent between Sintong and TBS nicotine-TDSs [9.58 (± 2.23) vs. 8.76 (± 1.88) mg/day/patch] but are lower than that from Habitrol™ system [15.13 (± 4.05) mg/day/patch]. Thus, for the statistical analysis of the pharmacokinetic parameters obtained need to be corrected for the difference in patch size and daily nicotine dose delivered. The results of statistical analysis suggested that Sintong and TBS nicotine-TDSs are bioequivalent to Habitrol™ system.     

Comparison of Disintegrant and Binder Activity of Three Corn Starch Products

This study demonstrates the differences obtained when using different corn starch products as both binder and disintegrant in pharmaceutical tablets. Formulations made with Fluftex W, Tablet White and Purity 21 starches were compared. In addition, Avicel PH101 was used in this study as a benchmark component whose properties are well understood.

Four test formulations containing hydrochlorothiazide were prepared by wet granulation. Starch was incorporated in both powder and paste form. All granulations were found to possess similar traits when evaluated based upon geometric mean diameter, particle size distribution, bulk/tap densities, powder flow rate and surface characteristics.

Tablets prepared from these granulations were shown to be similar when evaluated for degree of friability, weight and content uniformity. All starch formulations disintegrated within 30 seconds and produced similar dissolution profiles. Tablets produced with Avicel, however, were found to exhibit significantly longer disintegration times than the starch formulations. In addition, these tablets displayed a dissolution profile than was significantly different than the starch formulations, particularly during the earlier stages of the dissolution process.

When monitoring compression and ejection forces required to produce tablets of the same degree of hardness (≈6kg), Fluftex W and Tablet White granulations were found to use significantly lower forces than the Purity 21 granulation. This may be indicative of Fluftex W and Tablet White's superiority over Purity 21 in terms of binder capacity.     

Calculation of ordered equilibria for the Cadmium-Magnesium system

With excess Gibbs energies of Cd and Mg for disordered solutions, together withC _p values for the ordered α″ phase and some data for the phase boundaries, equations were developed for the Gibbs energies of ordered α′, α″, and α? phases. The equilibria that are compatible with these Gibbs energy functions are in reasonable accord with available experimental data. In addition, the values that are predicted for vapor pressure or emf measurements should be in a tractable range for experimental verification.     

Cell proliferation in human prostatic smooth muscle cells involves the modulation of protein kinase C isozymes

We have examined the role of protein kinase C in the regulation of foetal-calf serum-stimulated cell proliferation in human prostatic smooth muscle cells. The data showed that the proliferative effect to foetal-calf serum (10%, v/v) was partially inhibited by 12-(2-cyanoethyl)-6,7,12,13-tetrahydro-13-methyl-5-oxo-5H-indolo (2,3-a) pyrrolo (3,4-c)-carbazole (Go-6976), a selective Ca2+-dependent protein kinase C inhibitor, suggesting that Ca2+-dependent protein kinase C isozymes might play roles in this proliferative regulation. Additionally, foetal-calf serum caused a significant translocation of protein kinase C-betaII and -epsilon from a cytosolic to a membrane distribution. These findings combined with the aforementioned functional experiments suggest that foetal-calf serum-stimulated cell proliferation might involve the activation of protein kinase C-betaII in human prostatic smooth muscle cells; however, the role of protein kinase C-epsilon in mediating cellular functions other than cell proliferation remains further investigation in these cells.