An ordinal ranking model for the highway corridor selection problem

This paper examines the problem of corridor selection in highway design and routing. We present a model which is designed specifically to deal with ordinal information pertaining to the relative desirability of various potential corridors. A technique for combining ordinal rankings into a consensus is given. An approach to the problem of determining criteria weights is suggested.     

A new class of intelligent knowledge-based systems with an optimisation-based inference engine

In this paper we describe a new class of intelligent knowledge-based system (IKBS) which can be used principally for managerial decision making applications. This class of applications often requires a framework for knowledge acquisition which allows the system to use the knowledge of several experts. In addition, since in most business decision making the objective is maximise profits, there is a need for an inference engine which allows optimisation to be carried out. The new class of IKBS which is described in this paper has both these properties, i.e., the ability to use the knowledge of multiple experts in a convenient way and an inference engine which by performing optimisations is able to pick out the profit maximising decisions. As an illustration of these concepts, a system for allocation decision making is described. The system ‘Retail-opt’ allows the user to solve problems like allocation of space in retail outlets, allocation of space in mail order catalogues, pricing policy decisions for discounted airline tickets, etc. In the paper, the basic concepts behind ‘Retail-opt’ are described and an application of ‘Retail-opt’ to the problem of retail space allocation in a Scandinavian Department Store is given. A number of other systems which use these concepts for more complicated competitive decision making situations are also described.     

Induced luteolysis in the primate: rapid loss of luteinizing hormone receptors

The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.     

Cardioprotective effect of probucol in the atherosclerosis-prone JCR:LA-cp rat

The second epidermal growth factor (EGF)-like domain of human coagulation factor VII is a potent inhibitor of the FVIIa/tissue factor complex, the predominant initiator of coagulation in vivo. This domain has now for the first time been cloned and expressed in Escherichia coli as an affinity fusion protein. The fusion protein was secreted into the periplasm of E. coli and purified by affinity chromatography. The purified protein consisted of a fusion protein with the expected molecular weight, and in addition, a significant fraction of oligomers cross-linked by intermolecular disulfide bonds. Despite the presence of oligomers, the purified protein was a potent inhibitor of the extrinsic blood coagulation pathway with an IC50 value of about 20 microM. The biological activity was retained after liberation of the EGF domain by proteolytic cleavage.     

Serum concentrations of soluble adhesion molecules in patients with colorectal cancer

The concentrations of the soluble adhesion molecules E-cadherin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were investigated in 48 patients with colorectal cancer before treatment, and their relation to clinical, histological and routine laboratory parameters was examined. Data were collected on tumour stage at presentation, presence and sites of metastatic disease, tumour pathology and results of routine laboratory tests. Serum concentrations of ICAM-1 and VCAM-1 were significantly elevated in the patients with colorectal cancer in comparison with a group of healthy subjects (P < 0.00001). Levels of circulating ICAM-1 and VCAM-1 were increased both in patients with local and those with metastatic disease. Although elevated in some patients soluble E-cadherin and E-selectin concentrations were not significantly elevated compared with the control group (P = 0.71 and P = 0.052 respectively). The levels of circulating ICAM-1 were significantly correlated with those of VCAM-1 and E-selectin. A correlation was also found between the serum concentrations of E-selectin and ICAM-1 and alkaline phosphatase, total white cell count and platelet count. VCAM-1 was positively correlated with age and negatively with degree of tumour differentiation and haemoglobin concentration. The biological implications and possible clinical relevance of these findings are discussed.     

The radiographic and imaging characteristics of porous tantalum implants within the human cervical spine

STUDY DESIGN: Seven cadaveric cervical spines were implanted with a porous tantalum spacer and a titanium alloy spacer, and their radiographic and imaging characteristics were evaluated. OBJECTIVE: To determine the radiographic characteristics of porous tantalum and titanium implants used as spacers in the cervical spine. SUMMARY OF BACKGROUND DATA: Anterior decompressive surgery of the disc space or the vertebral body creates a defect that frequently is repaired with autologous bone grafts to promote spinal fusion. Donor site morbidity, insufficient donor material, and additional surgical time have spurred the development of biomaterials to replace or supplement existing spinal reconstruction techniques. Although the promotion of a solid bony fusion is critical, the implanted biomaterial should be compatible with modern imaging techniques, should allow visualization of the spinal canal and neural foramina, and should permit radiographic assessment of bony ingrowth. METHODS: Cadaveric spines containing the implants were imaged with plain radiography, computerized tomography, and magnetic resonance imaging. The image distortion produced by the implants was determined qualitatively and quantitatively. RESULTS: The tantalum and titanium spacers were opaque on plain radiographic films. On computed tomographic scans, more streak artifact was associated with the tantalum implants than with the titanium. On magnetic resonance imaging, the porous tantalum implant demonstrated less artifact than did the titanium spacer on T1- and T2-weighted spin echo and on T2*-weighted gradient-echo magnetic resonance images. Overall, the tantalum implant produced less artifact on magnetic resonance imaging than did the titanium spacer and therefore allowed for better visualization of the surrounding bony and neural structures. CONCLUSION: The material properties of titanium and porous tantalum cervical interbody implants contribute to their differential appearance in different imaging methods. The titanium implant appears to image best with computed tomography, whereas the porous tantalum implant produces less artifact than does the titanium implant on several magnetic resonance imaging sequences.     

Range of motion and complications after postburn heterotopic bone excision about the elbow

OBJECTIVE: To review the results of surgical management of heterotopic ossification about the elbow in burned patients. DESIGN: Retrospective analysis with long-term patient follow-up. MATERIALS AND METHODS: Eleven patients with 16 elbows requiring surgery were admitted between January 1, 1982 and December 31, 1993. A posterior approach to the elbow with release of the encased ulnar nerve +/- anterior transposition and transolecranon osteotomy to access extensive bone formation in the olecranon fossa was employed. Eight patients (11 elbows) were available for long-term follow-up conducted at mean 50 +/- 13 months after surgery. Long-term follow-up consisted of measurement of range of elbow motion, as well as clinical assessment of ulnar nerve function. MAIN RESULTS: For the 11 elbows examined postoperatively, the mean range of motion preoperatively in flexion-extension was 11 degrees +/- 5 degrees compared to 89 degrees +/- 12 degrees postoperatively (p < 0.001). Three patients with poor long-term results had ankylosis of the joint preoperatively. Of four patients with ulnar nerve paresis preoperatively, none had ulnar nerve dysfunction at follow-up. Of 16 elbows operated on, four (25%) had postoperative complications. Two suffered soft-tissue breakdown with hardware exposure requiring abdominal flap closure, one early failure of olecranon fixation, and one late infected hardware. CONCLUSIONS: Surgery for both limited range of motion as well as ulnar nerve compression is effective in cases of heterotopic ossification about the elbows of burned patients. Early operative intervention is indicated in progressive disease, particularly ulnar nerve palsy, if soft-tissue quality is adequate. Complications with 25% of elbows suggest that use of olecranon osteotomy for joint access may warrant review.     

Effects of aging, diet, and sex on plasma glucose, fructosamine, and lipid concentrations in barrier-raised Fischer 344 rats

We studied the relationships of plasma glucose, fructosamine, triglycerides, and cholesterol as a function of age, gender, and diet in barrier-raised Fischer 344 rats aged 5 to 26 months, fed a diet either ad libitum or restricted to 60% of the ad libitum caloric intake. The complex relationships of these plasma levels to age, gender, and diet led to the development of a model with age, diet, and sex as covariates. Overall, fasting plasma glucose concentrations were reduced by approximately 25% in rats on the restricted diet, compared to ad libitum-fed animals. There was a significant age-dependent decline in glucose levels in male animals, whereas in females there was an increase in plasma glucose with aging. Plasma fructosamine levels in calorie-restricted animals, overall, were reduced by 7% compared to levels in animals fed ad libitum. There was a significant positive correlation between plasma glucose and fructosamine levels. Mean plasma triglyceride content was decreased by 50% in calorie-restricted rats compared to ad libitum-fed animals. A significant decrease in triglyceride levels with increasing age was seen in male animals, and an increase with aging in females. There was a significant positive correlation between plasma glucose and triglyceride levels. Plasma cholesterol levels in calorie-restricted animals were reduced by 7% compared to levels in ad libitum-fed animals. An increase of cholesterol concentration with aging was significant in both males and females. Analysis of the data showed that there were significant differences between male and female Fischer 344 rats in the response of plasma glucose and fructosamine to aging and calorie restriction. Changes of plasma triglyceride and cholesterol with aging and dietary calorie restriction were also different in males and females. Studies of the effect of aging on glycemia and blood lipid content should take into account the contributions of animal sex.