Deformation behavior and properties of severe plastic deformation techniques for bulk materials: A review.

This paper presents a comprehensive review of the successful application of Severe Plastic Deformation (SPD) in producing ultra-fine grained (UFG) and nano-structured crystalline bulk materials. SPD achieves outstanding grain refinement without significantly altering the original dimensions of the workpiece, making it particularly useful for ductile materials that can withstand large strains under high hydrostatic pressure before failure. The study explores the grain refining mechanism during severe plastic deformation and its impact on the microstructure of metals. It also examines the use of SPD in hard to deform brittle materials like tungsten oxide, B2O3 glasses, and amorphous materials. The paper discusses the advantages and disadvantages of each technique, along with their applications and potential for combining more than one technique. The review is significant because it emphasizes recent progress in process development, which could potentially enable the industrialization of certain SPD techniques for specific applications. This paper fills the gap in the literature by addressing this issue. Overall, the review demonstrates the potential of SPD in metalworking and its application in the development of new UFG materials with improved mechanical properties.

Secondary bladder herniation in isolated gastroschisis justifies increased surveillance.

OBJECTIVES: To assess the perinatal outcome of fetuses with gastroschisis complicated by secondary bladder herniation. POPULATION AND MATERIALS: This was a retrospective study of all cases of isolated gastroschisis associated with bladder herniation managed at our institution. Prenatal ultrasound, obstetrical and perinatal information were collected. Pathology reports were also gathered. RESULTS: Out of 105 cases of gastroschisis managed at our institution, six (5.7%) were associated with secondary bladder herniation, two of them being diagnosed postnatally. Median gestational age at diagnosis of bladder herniation was 33.6 weeks (range 31-36) in five female and one male fetuses. Bladder herniation was associated with bowel dilatation in four cases (67%) and with pyelic dilatation in one case (17%). Despite increased surveillance, one male fetus died in utero. In four other cases, cesarean section was performed for fetal distress (three cases) or hyperechogenic bowels (one case). The five survivors had primary abdominal closure (n = 2) or staged repair (n = 3) with uneventful follow-up. CONCLUSION: Bladder herniation was present in 6% of apparently isolated gastroschisis. There was one intrauterine fetal death and four other cases were delivered for fetal distress. Increased surveillance seems justified.

Avascular necrosis of temporomandibular joint in sickle cell disease.

Avascular necrosis of temporomandibular joint (TMJ) in sickle cell disease was not reported in patients suffering from this disease. In this report, we present a case of a young Saudi female with avascular necrosis of the left temporomandibular joint associated with avascular necrosis of head of left femur, and early changes of infarction of the humeral head of the left shoulder. Clinical examination, laboratory investigations, tomography and computerized tomography scanning, confirmed the diagnosis of sickle cell disease, and the development of avascular necrosis of the left temporomandibular joint.

[Prenatal management of uncomplicated monochorionic biamniotic pregnancies]. / Surveillance des grossesses gémellaires monochoriales biamniotiques non compliquées.

Monochorionic pregnancies accounts for only 20% of twins but are responsible for most of their morbidity and mortality. There is no randomized study evaluating management of monochorionic pregnancies. Based on expert opinion, it is recommended that monochorionic pregnancies should be followed-up by practionners working with specialized centers with expertise in monochorionic pregnancies. Optimal follow-up should include a bi-monthly ultrasound evaluation.