his paper describes an approach for representing and tructuring the correct and erroneous knowledge of the student uring the learning process. This knowledge is structured in erms of goals, procedures, episodes and instances of concepts. hose entities are dynamically combined to represent the ognitive level of each learner. Empirical results show that our tructuring can help the tutor to build ...

In the following, 5 will denote the boundary of the unit ball in En, and u a variable point of S (so re is a unit vector, or "direction"). The polar equation of the boundary of DK is given by p = /»(«), uES, so piu) is the radius of DK in the direction u. Then p(w) is the maximum length of a chord of K having direction u—the length of a "diameter" of K having direction u. Let p. denote w-dimens...

The histogenetic and neoplastic potentials of defined regions of the 8th day mouse embryonic egg cylinder were examined following ectopic transfer to beneath the testis capsule. No differences in histogenetic potential were detected between anterior and posterior slices of the embryo, either when composed of all three germ layers or of embryonic ectoderm alone. Small anterior and distal fragmen...

We report 5 cases of sclerosing rhabdomyosarcoma. The patients included 4 adults and 1 adolescent. In the 5 cases, 3 tumors occurred in the head and neck region and 2 in an extremity. Histologically, all 5 tumors were characterized by the presence of abundant extracellular hyaline matrix, mimicking osteoid or chondroid tissue. They were composed mostly of primitive small round cells that displa...

Our objective was to study the effects of dietary energy source (fat or starch) on periestrus hormone profiles and embryonal survival in primiparous sows. During lactation, 48 primiparous sows were fed either a starch-rich or a fat-rich diet, at either a high (44 MJ NE/d) or a low (33 MJ NE/d) feeding level. After weaning, all sows received the same amount of feed (31 MJ NE/d from weaning to es...

Background: Rhabdomyosarcoma is a rare malignant soft tissue sarcoma and the most common sarcoma of childhood. The purpose of this study was to investigate the distribution of age and sex of patients, pathological subtypes and to determine the role of staging and classification of RMS on treatment outcome. Materials and Methods: This retrospective study included patients who diagnosed with RMS ...

Introduction Presence of two primary malignancies is rare and occurs in 3-5% of the cancer patients. As per our extensive internet research, this is the only reported case of a synchronous sino-nasal embryonal rhabdomyosarcoma with squamous cell carcinoma-tongue. The case report is important because of the rare diagnosis and the challenge we faced in the diagnosis and treatment of the pat...

Embryonal rhabdomyosarcoma (RMS) is a rare type of sarcoma, primarily seen in the pediatric and adolescent population. Three subtypes of embryonal RMS are described, with the botryoid type being the most common. The incidence of this disease in adult females is 0.4% to 1% with the affected age group being patients in the third to fourth decade of life. It is exceedingly rare in patients above 4...

Cancer cells have many abnormal characteristics enabling tumors to grow, spread, and avoid immunologic and therapeutic destruction. Central to this is the innate ability of populations of cancer cells to rapidly evolve. One feature of many cancers is that they activate genes that are normally associated with distinct developmental states, including germ cell-specific genes. This has historicall...

The development of the lamellar cells of mouse digital corpuscles (Meissner corpuscle) was studied by light and electron microscopic histochemistry for cholinesterase (ChE) The materials used were the hind limbs taken from fetuses at 14, 17 and 20 days of gestation, and from young mice at 1, 5, 7, 15 and 20 days after birth. Embryonal Schwann cells had non-specific ChE activity in the cisternae...