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This study aimed to evaluate the in vivo osseointegration of implants with hydrophobic antimicrobial GL13K-peptide coating in rabbit femoral condyles by micro-CT and histological analysis. Six male Japanese Rabbits (4 months old and weighing 2.5 kg each) were included in this study. Twelve implants (3.75 mm wide, 7 mm long) were randomly distributed in two groups, with six implants in the experimental group coated with GL13K peptide and six implants in the control group without surface coating. Each implant in the test and the control group was randomly implanted in the left or right side of femoral condyles. On one side randomly-selected of the femur, each rabbit received a drill that was left without implant as control for the natural healing of bone. After 3 weeks of healing radiographic evaluation of the implant sites was taken. After 6 weeks of healing, rabbits were sacrificed for evaluation of the short-term osseointegration of the dental implants using digital radiography, micro-CT and histology analysis. To perform evaluation of osseointegration, implant location and group was double blinded for surgeon and histology/radiology researcher. Two rabbits died of wound infection in sites with non-coated implants 2 weeks after surgery. Thus, at least four rabbits per group survived after 6 weeks of healing. The wounds healed without suppuration and inflammation. No implant was loose after 6 weeks of healing. Radiography observations showed good osseointegration after 3 and 6 weeks postoperatively, which proved that the tissues followed a natural healing process. Micro-CT reconstruction and analysis showed that there was no statistically significant difference (P > 0.05) in volume of bone around the implant between implants coated with GL13K peptide and implants without coating. Histomorphometric analysis also showed that the mineralized bone area was no statistically different (P > 0.05) between implants coated with GL13K peptide and implants without coating. This study demonstrates that titanium dental implants with an antimicrobial GL13K coating enables in vivo implant osseointegration at similar bone growth rates than gold-standard non-coated dental implants up to 6 weeks of implantation in rabbit femurs.

SUMMARYNew developments describing the theoretical basis towards an effective virtual-pulse (VIP) time integral methodology are proposed for general non-linear transient heat transfer problems. Primarily to validate the proposed methodology of computation, simple numerical test cases are provided and comparisons are also drawn with the implicit second-order-accurate Crank-Nicolson method. For the models tested, the proposed method has comparable or improved accuracy and stability characteristics. The VIP methodology introduced here for tackling non-linear thermal problems offers attractive features and is a viable alternative to traditional time-stepping practices. Efforts are underway to demonstrate the practical applicability to multi-dimensional thermal analysis.

This paper presents a model for understanding assembly programs for software maintenance. It is based on the theory that explicit representation of various structural and functional elements of code and multiple relationships among them will aid program Understanding and thus software maintenance. We present a parsing technique to extract all the required elements from assembly code to populate the model. The model is a reverse engineering technique. We use the term reverse engineering in its broad sense to include specification as well as design recovery. Most features of this model have been implemented in a tool named 'RETA' for Reverse Engineering Tool for Assembly programs.The model is useful for software maintenance activities such as program understanding, ripple effecl analysis, and program re-documentation. The ripple effect of a contemplated change is the parts of code that depend on the variable or a piece of code to be changed. Once the change is made, those parts need to be reexamined for possible modification. The model generates a functional menu for a given application. The menu describes the functionality of each routine. It is a hierarchical presentation of major program routines, the subroutines supporting each major routine and so on. A routine at any level of detail consists of one or more paths through the code. Paths are presented as control flow sequences between code blocks. Code blocks, and hence functionalities, use and modify data. The maintainer locates the routine to be modified at the lowest level of detail within the functional menu. This automatically slices out the set of paths, and hence the set of code blocks, that have a role in the functionality to be changed. The code blocks in the slice determine the data that are used and modified within the routine to be changed. Path analysis and associated data-used and datamodified information are used to determine which code blocks are to be changed and which data roles are to be modified. The same set of relations are applied in reverse to identify the ripple effect.KEY WORDS Software maintenance Design recovery Reverse engineering Assembly language Computer aided software engineeringThe high cost of software maintenance and the importance of effective maintenance techniques are widely known (Heninger, 1980;Lehman, 1980;Martin, 1983; Ramamoorthy ef af., 1984;Pressman, 1987; Hazzah, 1989). Even a small percentage improvement in the maintenance process can result in significant savings to organizations using large applications. Major improvements in the maintenance process can have far-reaching effects by reducing the investment required to support software, extending the useful life of existing systems, and expanding the range of problems that can be realistically addressed by large software applications.

SUMMARYAn overview of new and recent advances towards a VIrtual-Pulse (VIP) time-integral methodology for general linear/non-linear dynamic systems is presented. Attention is focused on providing a brief overview and an indepth evaluation of the developments, methodology, computational issues and implementation aspects for practical problems. Different from the way we have been looking at the developments encompassing existing direct time-integration type methods and mode superposition techniques, the proposed methodology capitalizes on the computational attributes of both and thereby offers new perspectives and several attractive favourable features in terms of stability and accuracy, storage, and computational costs for a wide variety of inertial dynamic problems. Recently, the authors have shown the theoretical developments via the VIP methodology for transient structural and for transient thermal problems?-' The purpose of the present paper is to summarize the theoretical developments, improve upon the computational/implementation aspects for general linear/non-linear dynamic structural problems, and demonstrate the pros and cons via numerous illustrative test cases. The theoretical analysis and results of several test cases show that the VIP methodology has improved accuracy/stability characteristics and computational advantages in comparison to the commonly advocated explicit and implicit methods such as the Newmark family. Overall, an analysis of the theoretical developments, algorithmic study, and the implementation and evaluation of the formulations strongly suggest the proposition that the VIP methodology is a viable alternative for general structural dynamic applications encountered in practical engineering problems.