Novel concepts in steel design

New forms steel is few and far between.In this lecture I will illustrate three discoveries which have the potential of making significant new contributions to the applications of steel as an engineering material.One of these discoveries deals with the first ever bulk nanostructured metal which can be made on a large scale,cheaply and with properties which are superior to carbon nanotubes.The second is a highly formable steel whose properties are not matched by any available today.And the third,a welding material which is designed to transform in such a way that residual stresses are eliminated from joints.     

Computer-assisted diagnosis based on computer-based image interpretation and 3D-visualization

PURPOSE: To survey methods for 3D data visualization and image analysis which can be used for computer based diagnostics. MATERIAL AND METHODS: The methods available are explained in short terms and links to the literature are presented. Methods which allow basic manipulation of 3D data are windowing, rotation and clipping. More complex methods for visualization of 3D data are multiplanar reformation, volume projections (MIP, semi-transparent projections) and surface projections. Methods for image analysis comprise local data transformation (e.g. filtering) and definition and application of complex models (e.g. deformable models). RESULTS: Volume projections produce an impression of the 3D data set without reducing the data amount. This supports the interpretation of the 3D data set and saves time in comparison to any investigation which requires examination of all slice images. More advanced techniques for visualization, e.g. surface projections and hybrid rendering visualize anatomical information to a very detailed extent, but both techniques require the segmentation of the structures of interest. Image analysis methods can be used to extract these structures (e.g. an organ) from the image data. DISCUSSION: At the present time volume projections are robust and fast enough to be used routinely. Surface projections can be used to visualize complex and presegmented anatomical features.     

Some new concepts of cardiac myxoma

The surgical treatment of cardiac myxoma in 211 consecutive cases (single tumor in 204 cases, multiple in 7, and recurrent in 3) from Dec. 1975 through Dec. 1993 was reviewed. Totally 228 myxomas were found and 215 operations performed. Data from this series and literature show that there were some complicated cases so that cardiac myxoma can not be simply regarded as a benign tumor only, but may be classified into two kinds: simple (or sporadic) cardiac myxoma and complicated cardiac myxoma. The latter includes myxoma complex, familial myxoma, and myxoma from multicenters. The clinical features, main points of diagnosis and surgery are concisely summarized.     

Molecular design of anti-MRSA drugs

The true nature of resistance of methicillin-resistant Staphylococcus aureus (MRSA) is penicillin-binding protein 2' (PBP2'). Affinities of almost all beta-lactam antibiotics to PBP2' were very low. Therefore, MRSA which produces PBP2' shows resistance to all beta-lactam antibiotics. However, PBP2' has a different affinity to each beta-lactam antibiotic. For this reason, we thought that some derivatives of beta-lactam compounds could have high affinity to PBP2'. Accordingly, we developed cephem compounds which are more stabile and safe than previous penicillin and carbapenem compounds. Firstly, we investigated the side chain at C-7 position on 2-thioisocephem skeletal. Hydroxyimino-aminothiazol at C-7 position on 2-thioisocephem skeletal had the strongest activity against MRSA. Secondly, we investigated the linkage styles at C-3 position on 2-thioisocephem skeletal which were methylene, vinyl, and propylene. The compound of vinyl linkage style at C-3 position on 2-thioisocephem skeletal showed high activity against MRSA. Finally, we investigated 1-thiocephem, 2-thioisocephem, and 2-oxaisocephem as cephem-skeletals. Simultaneously, we studied C-3 linkage styles which were methylene, vinyl, and propylene. From these results, we found out that the compound of hydroxyiminoaminothiazol at C-7 position and vinyl linkage style at C-3 position on 1-thiocephem skeletal has superb activity against MRSA.     

Acquisition of new concepts by two amnesic patients

Two Korsakoff amnesics (A.G. and G.S.) and two control subjects were taught six new concepts. Each concept was composed of three parts: the name of the concept, the context in which the concept originated and its definition. The learning procedure consisted of two phases: (1) learning the concept names and definitions by means of the vanishing-cues method; (2) practice on examples of the concepts through a classification task: examples were either set in the same context as that given in the original definition or in mixed contexts (same and new contexts). Subjects were then tested after 24 hours, a week and a month on their ability to identify new examples as belonging to one of the conceptual rules studied (transfer tests). Both patients showed substantial learning. Patient A.G. was slow and dependent of the first letter cues in the vanishing-cues learning phase but nevertheless, she acquired a large and flexible conceptual knowledge and this was especially true for concepts that were practised by means of mixed-context examples. Patient G.S. easily learned to associate the definitions with the concept names but her conceptual knowledge remained more limited. These results confirm the existence of a semantic learning ability in amnesic patients. They also suggest that under appropriate learning conditions, amnesics may eventually acquire a new flexible conceptual knowledge.     

Neuropathology in multiple sclerosis: new concepts

Nitric oxide (NO) is receiving interest because of its use in patients with acute respiratory distress syndrome. Because more studies are being conducted, researchers are discovering a vast array of physiological effects attributable to NO. NO has been implicated as having a role in the endogenous regulation of blood pressure; smooth, skeletal, and cardiac muscle relaxation; renal and immune system functioning; and selective pulmonary vasodilation. This article looks at the pharmacological and physiological effects of NO and its current use in the clinical setting.     

New lipid lowering drugs and new effects of old drugs

Old lipid acting drugs (fibrates, resins and niacin) continue to demonstrate morbidity and mortality benefits with variable efficacy and safety. Controlled trials have provided efficacy and safety data that support the use of statins as the first choice in the treatment and prevention of atherosclerosis. Knowledge of old and new mechanisms of action, optimal doses, pharmacokinetic behavior and drug interactions improve the safety and effectiveness of these hypolipidemic agents.     

Antibacterial drug therapy. Focus on new drugs

This article will focus on the drugs for which there has been a recent or renewed interest in veterinary medicine. Some of these are new drugs that were recently introduced. Others discussed may be human-label drugs for which there has been recent interest in veterinary medicine because of the need for a more active drug or convenient regimen. For drugs such as the aminoglycosides included here, recent information has provided us with updated dosage guidelines.     

Recent trend on the development of new anticancer drugs

More than 35 candidate drugs have been under their clinical studies in Japan currently. These include antimetabolites, drugs originated from natural products, miscellaneous compounds and hormones. Since the time of appearance of cisplatin and taxol, we found the possibility to discover new active drugs against human solid cancers. Our recent clinical studies on topoisomerase inhibitors and microtubules inhibitors have also been proving the clinical usefulness of these drugs for cancer treatment. From now on, we have to think the drug development from ethical aspects, improving quality of life and prolonging the survival of the treated patients. For these purposes, we have to be careful to choose candidate drugs for their clinical trials.     

Nitroglycerin: new concepts about an old drug

The ultimate goal of the cone method of colostomy irrigation is to return patients with colostomies to their former role in society with confidence in themselves to the extent that having a colostomy is not considered a handicap. The results have generally been excellent. We believe all patients with stomas should be afforded the opportunity to attempt colostomy irrigation.     

Interdigital athlete's foot: new concepts in pathogenesis

In our view, interdigital athlete's foot usually begins with invasion of the horny layer by dermatophytes. Because of hot weather, sweating, exercise, or tight shoes, enough moisture accumulates to stimulate an overgrowth of bacteria. Large numbers of normally resident aerobic diphtheroids cause the common wet, macerated type of athlete's foot, while an overgrowth of Gram-negative organisms, such as Pseudomonas and Proteus, is responsible for the more serious cases. The dry, scaly type (dermatophytosis simplex) often alternates with the wet, macerated type (dermatophytosis complex). Flare-ups are common in summer and can be experimentally induced by occlusion of fungus-infected feet. Suppression of bacteria is essential in treating symptomatic athlete's foot. This can be accomplished by exposing the feet to air (eg, wearing sandals) to enhance evaporation of water and prevent the accumulation of excess moisture that stimulates bacterial overgrowth. Topical antibiotics are another approach, with the ideal perhaps being an agent with both broad-spectrum antibacterial and antifungal activity. The newer imidazoles are broad-spectrum compounds but have limited activity against Gram-negative organisms. Our agent of choice, aluminum chloride, combines broad-spectrum antimicrobial activity with chemical drying, a two-pronged attack. We view drying as the decisive element. We doubt that any local treatment can permanently eradicate athlete's foot. Potent antifungal agents can virtually exterminate interdigital dermatophytes, but the inevitable presence of infection in the nails or on the soles assures reinfection. In shoe-wearing populations living in temperate climates, interdigital athlete's foot is mainly a seasonal disease. The various therapies discussed provide a variety of approaches to prevent or ameliorate hot-weather exacerbations.     

A new pharmacodynamic model of antiarrhythmic drugs

A new model using rational functions is proposed for the pharmacodynamics of antiarrhythmic drugs. It can describe both positive and negative effects, as well as different asymptotic effect levels. The method for determining parameters is presented and applied to experimental data. This model fits data better than traditional models.     

Treatment of the epilepsy: new drugs

New advances in the knowledge on the physiopathogenesis of epilepsy and their relationship with sodium and calcium channels and with the excitatory and inhibitory neurotransmitters actions have recently been developed. These knowledges have produced the research on new antiepileptic drugs which action places have specially based on the known impaired mechanisms. As the conventional drugs, the new therapeutic tool have produced a great advance in the therapy of epileptic events, specially in the refractory seizures, which represent 25-30% of the whole group of epilepsies. In the present work, we review the new drugs, ones have been registered, in order to their pharmacological properties, their efficacy their safety and their clinical indications as first-election or adjuvant drugs. We also discuss their known side adverse effects.