Description of a robotics-oriented relational positioning methodology

This paper presents a relational positioning methodology for flexibly and intuitively specifying offline programmed robot tasks, as well as for assisting the execution of teleoperated tasks demanding precise movements.In relational positioning, the movements of an object can be restricted totally or partially by specifying its allowed positions in terms of a set of geometric constraints. These allowed positions are found by means of a 3D sequential geometric constraint solver called PMF – Positioning Mobile with respect to Fixed. PMF exploits the fact that in a set of geometric constraints, the rotational component can often be separated from the translational one and solved independently.

Use of anisotropic modelling in electrical impedance tomography: description of method and preliminary assessment of utility in imaging brain function in the adult human head.

Electrical Impedance Tomography (EIT) is an imaging method which enables a volume conductivity map of a subject to be produced from multiple impedance measurements. It has the potential to become a portable non-invasive imaging technique of particular use in imaging brain function. Accurate numerical forward models may be used to improve image reconstruction but, until now, have employed an assumption of isotropic tissue conductivity. This may be expected to introduce inaccuracy, as body tissues, especially those such as white matter and the skull in head imaging, are highly anisotropic. The purpose of this study was, for the first time, to develop a method for incorporating anisotropy in a forward numerical model for EIT of the head and assess the resulting improvement in image quality in the case of linear reconstruction of one example of the human head. A realistic Finite Element Model (FEM) of an adult human head with segments for the scalp, skull, CSF, and brain was produced from a structural MRI. Anisotropy of the brain was estimated from a diffusion tensor-MRI of the same subject and anisotropy of the skull was approximated from the structural information. A method for incorporation of anisotropy in the forward model and its use in image reconstruction was produced. The improvement in reconstructed image quality was assessed in computer simulation by producing forward data, and then linear reconstruction using a sensitivity matrix approach. The mean boundary data difference between anisotropic and isotropic forward models for a reference conductivity was 50%. Use of the correct anisotropic FEM in image reconstruction, as opposed to an isotropic one, corrected an error of 24 mm in imaging a 10% conductivity decrease located in the hippocampus, improved localisation for conductivity changes deep in the brain and due to epilepsy by 4-17 mm, and, overall, led to a substantial improvement on image quality. This suggests that incorporation of anisotropy in numerical models used for image reconstruction is likely to improve EIT image quality.

Malignancy transformation of chronic osteomyelitis: description of 6 cases of Marjolin's ulcers

Marjolin's ulcer describes any malignant transformation of a chronic inflammatory lesion. In the majority of cases, a squamous cell carcinoma is diagnosed. Malignant transformation occurs usually after a long period of latency of chronic infection; it takes approximately 35 years on average. There are no typical clinical presentations, but several indirect signs may suggest the malignant transformation, such as increased or changed discharge, pathologic fracture, a slow-growing exophytic mass, or other suggestive signs of malignant transformation, which should prompt to biopsy for histological exam. The diagnosis of chronic osteomyelitis should not prevent to search for carcinoma. We present six patients with chronic osteomyelitis that developed well-differentiated squamous cell carcinoma. All patients were older than 50 years (mean 60 years, range 52-77 years). Five Marjolin's ulcers were located on the lower limb and one on the arm. The average time of the chronic discharging osteomyelitis before diagnosis of carcinoma ranged between 12 and 40 years. All patients were treated by amputation of the affected limb. None had metastasis, and one patient developed local recurrence and received palliative treatment. Our study emphasizes that Marjolin's ulcer should be considered as a rare but significant long-term complication of chronic osteomyelitis. The finding of microorganisms should not prevent from further diagnostic procedures by histopathological examination so that the correct surgical treatment can be performed.

Experimental and clinical radiofrequency ablation: proposal for standardized description of coagulation size and geometry.

BACKGROUND: Radiofrequency (RF) ablation is used to obtain local control of unresectable tumors in liver, kidney, prostate, and other organs. Accurate data on expected size and geometry of coagulation zones are essential for physicians to prevent collateral damage and local tumor recurrence. The aim of this study was to develop a standardized terminology to describe the size and geometry of these zones for experimental and clinical RF. METHODS: In a first step, the essential geometric parameters to accurately describe the coagulation zones and the spatial relationship between the coagulation zones and the electrodes were defined. In a second step, standard terms were assigned to each parameter. RESULTS: The proposed terms for single-electrode RF ablation include axial diameter, front margin, coagulation center, maximal and minimal radius, maximal and minimal transverse diameter, ellipticity index, and regularity index. In addition a subjective description of the general shape and regularity is recommended. CONCLUSIONS: Adoption of the proposed standardized description method may help to fill in the many gaps in our current knowledge of the size and geometry of RF coagulation zones.

Histological description of seminiferous epithelium and cycle length of spermatogenesis in the water shrew Neomys fodiens (Mammalia: Soricidae).

Recently, we examined the spermatogenesis cycle length in two shrews species, Sorex araneus characterized by a very high metabolic rate and a polyandric mating system (sperm competition) resulting in a short cycle and Crocidura russula characterized by a much lower metabolic rate and a monogamous mating system showing a longer cycle. In this study, we investigated the spermatogenesis cycle in Neomys fodiens showing an intermediate metabolic rate. We described the stages of seminiferous epithelium according to the spermatid morphology method and we calculated the cycle length of spermatogenesis using incorporation of 5-bromodeoxyuridine into DNA of the germ cells. Twelve males were injected intraperitoneally with 5-bromodeoxyuridine, and the testes were collected. For cycle length determination, we applied a recently developed statistical method. The calculated cycle length is 8.69 days and the total duration of spermatogenesis based on 4.5 cycles is approximately 39.1 days, intermediate between the duration of spermatogenesis of S. araneus (37.6 days) and C. russula (54.5 days) and therefore congruent with both the metabolic rate hypothesis and the sperm competition hypothesis. Relative testes size of 1.4% of body mass indicates a promiscuous mating system.

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 1, A-Colytea

Collection : Archives de la linguistique française ; 381

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 5, T-Zupain

Collection : Archives de la linguistique française ; 381

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 3, G-MYU

Collection : Archives de la linguistique française ; 381

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 2, Coma-Fyonie

Collection : Archives de la linguistique française ; 381

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 2, Coma-Fyonie

Collection : Archives de la linguistique française ; 382

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 1, A-Colytea

Collection : Archives de la linguistique française ; 382

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 3, G-Myurus

Collection : Archives de la linguistique française ; 382

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 5, T-Zytomiérs

Collection : Archives de la linguistique française ; 382

Dictionnaire universel françois et latin : contenant la signification et la définition... des mots de l'une et de l'autre langue... la description de toutes les choses naturelles... l'explication de tout ce que renferment les sciences et les arts.... Tome 4, N-Székéli

Collection : Archives de la linguistique française ; 382