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Biomedical subjects

S Cavalieri

Publications and source records attributed to S Cavalieri.

At least 19 recordsLinked to original sources
PubMed1999

Solving linear integer programming problems by a novel neural model.

The paper deals with integer linear programming problems. As is well known, these are extremely complex problems, even when the number of integer variables is quite low. Literature provides examples of various methods to solve such problems, some of which are of a heuristic nature. This paper proposes an alternative strategy based on the Hopfield neural network. The advantage of the strategy essentially lies in the fact that hardware implementation of the neural model allows for the time required to obtain a solution so as not depend on the size of the problem to be solved. The paper presents a particular class of integer linear programming problems, including well-known problems such as the Travelling Salesman Problem and the Set Covering Problem. After a brief description of this class of problems, it is demonstrated that the original Hopfield model is incapable of supplying valid solutions. This is attributed to the presence of constant bias currents in the dynamic of the neural model. A demonstration of this is given and then a novel neural model is presented which continues to be based on the same architecture as the Hopfield model, but introduces modifications thanks to which the integer linear programming problems presented can be solved. Some numerical examples and concluding remarks highlight the solving capacity of the novel neural model.

Linear Models↗
PubMed1997

Anaplastic progression of classic Kaposi's sarcoma.

We describe a case of classic Kaposi's sarcoma (KS) in an Italian HIV-negative patient, with bone involvement and progression to anaplastic histotype. At the age of 22, violaceous patches of KS appeared on his feet. At the age of 50, he noted the appearance of a violaceous firm nodule on his right wrist. The lesions grew rapidly and became ulcerated. Radiotherapy led to a complete remission of symptoms. At the age of 55, a subcutaneous nodule developed on the proximal third of the right forearm associated with a wide painful edema of the right forearm and the proximal third of the right arm. The nodule enlarged rapidly, and an X-ray of the right forearm revealed the presence of a large osteolytic area of the ulna. A biopsy specimen from the right ulna showed bone erosion by a mesenchymal neoplasia with a high degree of malignancy. The right arm was amputated, and histologic examination of the surgical material confirmed the diagnosis of undifferentiated spindle-cell malignant neoplasia strongly positive for factor-VII-related antigen and CD34 antigen. Three years after surgical treatment, no recurrences have been observed.

Adult↗
PubMed1997

[Huangdi Neijing: a classic book of traditional Chinese medicine].

According to the data of the recent archaeological excavations, the history of traditional Chinese medicine begins in the neolithic period (10,000-4,000 years ago). The fundamental principles of the traditional Chinese medicine may be interpreted on the basis of two classic theories of Chinese thought: the Yin-Yang theory and the five phases theory. The former stated that our reality is the product of the continuous interaction and transformation of the Yin and Yang principles. The latter recognise the existence of five emblematic groups in which everything regarding humankind and nature may be classified. The five phases interact in two different ways: the cycle of production (Sheng) and the cycle of control (Ke). Theoretical basis of traditional Chinese medicine are described on the Huangdi Neijing (The Book of Yellow Emperor's: a classic of internal medicine) written during the period 475-225 b.C. as a dialogue between the mythical Emperor Huangdi and his physician Qibo. The book is divided into two parts: the Suwen (Questions about living matter) and Lingshu (The vital axe). Each part is composed of 81 sections. In this book are set correspondences between phases and organs, viscera, feelings, body fluids, flavours, foods, colours, and so on. We can also find the description of blood (Xue) and energy (Qi) circulation and the pathways of main, collateral and curious vessels. The origins of disease are also reported on the Huangdi Neijing. As regards the psychological point of view, special attention is dedicated to dreams and their possible causes and to the description of various kind of mental illness. The unknown Authors underline the five defects and the four mistakes of the physician, pointing out the importance to avoid them. Finally, it must be mentioned their special care to the principles of preventive medicine.

History, Ancient↗
PubMed1996

Manipulator adaptive control by neural networks in an orange picking robot.

The paper focuses on the use of neural networks for process identification in an orange-picking robot adaptive control system. The results that will be shown in the paper refer to a study carried out under the European Community ESPRIT project "CONNY", dealing with the application of neural networks to robotics. The aim of the research is to verify the possibility of integrating a neural identification module in a traditional system to control the movement of the manipulators of the robot. The paper illustrates integration of neural identification in the existing orange-picking robot control system, highlighting the improvement of performance obtainable. Although the proposal refers to a specific robot, it can be applied to any system with the same dynamic features.

Adaptation, Psychological↗
PubMed1995

[Eosinophilic pustular folliculitis and Ofuji disease. A case report].

We describe the case of a young man of Calabrian origin, who came to our observation for the appearance of erythematous pustular, intensely itching, lesions on the arms, trunk and, in a less extent, on the face. The blood count revealed a differential cell count of 16.8% eosinophils. Serum IgE levels were elevated (1000 IU/ml), and T cell subsets showed an increase in CD8+ and a decrease in CD4+ with an inversion of CD4+/CD8+ ratio (= 0.78). The result of the following investigations were either normal or negative: anti-(ds)DNA antibody, anti-nuclear antibody, anti-smooth muscle antibody, anti-striated muscle antibody, serological tests for viral, bacterial, fungal and parasitic diseases and cultural examination of the material from lesion. Histopathological examination of a biopsy specimen from the left arm showed the presence of abundant perivascular inflammatory infiltrate in the dermis and inflammatory infiltrate, with numerous eosinophils, around sebaceous glands. Taken together, all these data suggest the diagnosis of eosinophilic pustular folliculitis, a dermatosis of unknown etiology, with a histopathological picture identical to Ofuji's disease. Eosinophilic pustular folliculitis can be associated with HIV infection or haematological diseases (as non-Hodgkin lymphomas, myeloma, etc.); it was also reported in adult immunocompetent healthy individuals and in children. On the basis of our findings, we propose that this case should be classified as an idiopathic form, as we were not able to demonstrate any associated disease.

Adult↗
PubMed1995

[Cutaneous tuberculosis: a case of difficult classification].

We describe a case of cutaneous tuberculosis in a 25-year-old Philippine man. Erythematous papulo-nodular lesions, measuring 0.5 to 1 cm, were present on lower limbs; a 2 cm nodule was located on the left flank. The examination of the skin biopsy showed the presence of a superficial and deep perivascular dermatitis with histiocytes, lymphocytes and plasma cells. Ziehl-Nielsen stain for mycobacterium were negative, while the cultural examination led to the isolation of M. tuberculosis. Direct smear and cultural examination of sputum for M. tuberculosis were negative; chest and skeletal roentgenograms, syphilis and HIV infection serology, haematological and hematochemical examinations and urinalysis were negative. Specific treatment with isoniazid, rifampin and ofloxacin led to a rapid remission of cutaneous lesions. This case was particularly difficult to classify, but the Authors think it would be considered a tuberculid.

Adult↗
PubMed1993

Neural strategies to handle routing in computer networks.

In this paper, the authors adopt a neural approach to deal with the problem of routing in a packet switching network. The aim is to define a routing strategy which will combine the advantages of both the centralized and the distributed approaches. The neural approach presented is based on the idea of inserting a neural network (N/N) into each node in the computer network which will be responsible for computing the route between its node and the immediately adjacent one. Two distributed routing solutions are presented in the paper based on an optimizing network and a mapping network. The routing obtainable and the implementation resources needed for the two approaches are evaluated. Finally, the performance offered by the neural strategies proposed is compared with that offered by classical distributed and centralized routing solutions. As a parameter of merit, the effect of overloading caused by the additional traffic present in each solution is used.

Algorithms↗
PubMed1991

Recurrent empty follicle syndrome.

We report a case of recurrent empty follicle syndrome over two stimulated cycles in a patient having immunological infertility. All follicles contained follicular fluid but aspirated granulosa cells were rarely observed. No oocytes were obtained from a total of 24 follicles.

Adult↗
PubMed1989

Laser dentistry: root canal diagnostic technique based on ultraviolet-induced fluorescence spectroscopy.

A diagnostic technique to detect residual tissues at different levels of the root canal during an endodontic treatment is presented. The diagnostic system is based on ultraviolet-induced fluorescence spectroscopy and uses suitable optical fibers for local delivery of excitation light and to collect back fluorescence spectra. Spectra of root canal tissues have been obtained from split teeth by labeling with a fluorescent solution. Residual tissue can be discriminated in respect to healthy dentin because of their different spectral responses: the spectral shape of the first response shows a clear peak at 530 nm because of a selective absorption of the fluorescent dye, whereas for the second response, the spectral curve monotonically increases toward ultraviolet wave-lengths with no particular structure. This technique has been tested on unsplit teeth simulating operative conditions. A compact spectroscopic system has been devised that can be easily integrated in an excimer laser system to perform residual tissue detection during laser cleaning of the canals.

Fiber Optic Technology↗
PubMed1989

Whole-lung tomography in urologic malignancy.

The place of whole-lung tomography in urologic malignancy has not been established. We reviewed 88 cases of known or suspected urologic malignancy in which tomography was used. Most patients had renal, bladder, or testicular tumors. Of the 68 patients with negative screening chest roentgenograms, all but 2 had negative tomograms. One of these 2 patients had a normal chest film (the other had extrapulmonary metastasis), and he did not have the renal carcinoma initially suspected. Tomography discovered no metastases from urologic malignancy that was not already known about from the screening x-ray film. In 20 cases with a positive screening x-ray film, tomography was of limited value. It cleared two suspicious chest films and added information on extent of metastatic involvement in three. We conclude that whole-lung tomography adds little information not available by chest roentgenogram in our selected population, and with a negative screening chest film no additional chest study is needed.

Costs and Cost Analysis↗
PubMed1989

Calcitonin inhibition of growth hormone-releasing hormone-induced GH secretion in normal men.

Calcitonin has been shown to modulate pituitary hormone secretion in a variety of ways. In this study we examined the effects of a salmon calcitonin infusion on GHRH-induced GH secretion in 5 normal men. In addition, in vitro experiments were performed using primary cultures of rat anterior pituitary cells in order to examine whether there is a direct pituitary effect of CT. Infusion of CT significantly blunted the GH response to GHRH in all subjects without affecting basal GH secretion or plasma calcium levels. Infusion of CT was accompanied by significant increases in ACTH, beta-endorphin, cortisol and free fatty acid levels, and by a significant decrease in serum insulin levels. The addition of CT to primary cultures of rat pituitary cells did not alter basal or stimulated secretion of GH or ACTH. These results indicate that: 1) CT blunts the GH response to GHRH; 2) CT infusion results in the stimulation of the hypothalamic-pituitary-adrenal axis, and 3) this effect is probably exerted at the hypothalamic level, since no direct activity of CT was documented in vitro on either GH or ACTH secretion.

Adrenocorticotropic Hormone↗