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The impact of diabetes mellitus (DM) on the survival of patients with hepatocellular carcinoma (HCC) is still unclear. The present study aims to draw a firm conclusion in terms of evaluating the impact of DM on the prognosis of HCC after hepatectomy.The pattern of recurrence for HCC was often stratified into early-stage (2 years) and late-stage (≥2 years) recurrence. Because the early-stage recurrence was mainly attributed to aggressive tumor pathological characteristics, patients who recurrence or die within 2 years were excluded. Cumulative overall survival (OS) and recurrence-free survival (RFS) were determined by the method of Kaplan-Meier, and the independent risk factors of OS/RFS were determined by Cox regression analysis.A total of 426 patients were eventually included. The 3- and 5-year OS in patients with and without DM was 83.7%, 55.1%; and 90.9%, 77.4%, respectively. Multivariate analysis showed that DM was an independent risk factor for OS (HR 1.166, 95% CI 1.056-2.036,DM is an independent risk factor for long-term prognosis in patients with HCC. Patients with DM after hepatectomy for HCC, thus, need to actively control DM and closer follow-up.

Thin-walled tubes have long been used as energy absorbing structures, owing to their high specific energy absorption (SEA) capacity. But, they are associated with substantial high values of peak cr...

This paper presents a discretised musculoskeletal multi-body spine model using the LifeMOD Biomechanics Modeller. This was obtained by refining spine segments in cervical, thoracic and lumbar regions into individual vertebra segments, using rotational joints representing the intervertebral discs, building various ligaments between vertebrae and implementing necessary lumbar muscles. To validate the model, two comparison studies were made with in vivo intradiscal pressure measurements of the L4-L5 disc as well as extension moments, axial force and shear force around L5-S1 obtained from spine models available in the literature. The results indicated that the present model is in good correlation with both cases and matches well with experimental data which found that the axial forces are in the range of 3929-4688 N and shear forces up to 650 N. This study provides a preliminary overview of our ongoing work towards building bio-fidelity discretised multi-body spine models for investigating various medical applications. These models can be useful for incorporation into design tools for wheelchairs or other seating systems which may require attention to ergonomics as well as assessing biomechanical behaviour between natural spines and spinal arthroplasty or spinal arthrodesis. Furthermore, these models can be combined with haptic-integrated graphic environments to help surgeons to examine kinematic behaviours of scoliotic spines and to propose possible surgical plans before spine correction operations.

The haptic playback system is important to the training of sensorimotor skills. With the intent for training medical students in surgery, a real-time incision training system with haptic playback is developed in this paper. This system has three modes. Mode I sets the standard cutting trajectory of the incision operation carried out by an expert. Mode II allows students to track the trajectory by haptic guidance to feel the expert's motion. Mode III lets students experience the force feeling of the expert by following the trajectory via the visual cue. To accomplish these tasks, an adjustment proportional-derivative (PD) controller and a cutting model with real-time haptic feedback are devised. The cutting model adopts the mesh adaption method for real-time simulations of progressive cutting operations. These devised methods have been configured with a haptic device PHANToM Desktop to validate the capability of the proposed training system.

Information availability is a key factor for business success and competitive advantage. While created by design engineers, product structure is accessed and referenced by other users involved in product lifecycle from various departments. However, there is a lack of efficient ways of managing product structure information for enterprise business process integration. This study proposes a unified product structure management model to fill in this gap. With this proposed model, the product structure is managed in a unified way and can be accessed by different people with various disciplines in the right formats throughout the entire product lifecycle, including business processes of quotation, sales order processing, design, planning, scheduling, production, and delivery. This research is part of the enterprise business information management system project whose purpose is to streamline the information management for key business processes to integrate multi-disciplines in an enterprise for product develo...

A process planner for three-dimension prismatic parts is developed in this paper by utilizing case-based techniques. A three-dimension prismatic part is represented by a set of primary features (such as holes, pockets, slots, etc). The subplan candidates for individual features of a part are first generated by the proposed system via a backward inference planner based on the specifications of cutting tools available in a factory. The system then combines all subplans into the final process plan for a given part based on the merging information. The merging information is the information regarding the manufacturing environment of a factory (i.e. machine layout, transfer line, etc), and plays a key role in the process planning. Generally, the merging information is contained in old plans, and will be extracted by the system using case-based techniques. This way, the proposed system can generate a practical process plan for a given part based on case histories provided by the factory itself. The proposed pro...

In this study, polycaprolactone/mineral trioxide aggregate (PCL/MTA) scaffolds were successfully fabricated via an electrohydrodynamic jet (or E-jet) 3D printing system developed by our group. The viscosity of the composited solutions and the key process parameters (i.e. applied voltage and feed rate) were investigated to achieve an optimal process condition. To investigate the potential of PCL/MTA scaffolds to support regeneration ability for dentin related tissue, we seeded dental pulp stem cells on the scaffolds, and compared the results with cell-seeded PCL scaffolds. Assessment of cell viability and proliferation using live/dead cell staining and MTS assay showed compatibility of PCL and PCL/MTA scaffolds for cellular attachment and growth. These scaffolds could be used for fabrication of three-dimensional tissues and in future could be applied to dentin and periodontal tissue engineering applications.

The basic idea of case-based reasoning (CBR) is to retrieve and modify the most relevant prior case to match new requirements. In this paper, a framework for a process planning system for machining of axisymmetric parts using case-based reasoning is introduced. It is composed of four major components: retriever, modifier, simulator, and repairer. When a desired axisymmetric part is to be machined, the proposed system first retrieves the most relevant case from the case library as a plan candidate. Since the plan candidate is rarely the same as the desired one, the system performs modification, simulation, and reparation on it. The proposed system has been implemented on a Sun workstation using the ACIS geometric modeler and C++.