Post-weld heat treatment stress relaxation in Zircaloy 4 plasma welds

We have studied the effect of a post-weld heat treatment on plasma arc welds on Zircaloy 4 plates. The samples consist of two 100 mm long, 50 mm wide, and 6.25 mm thick plates, welded along the rolling (longitudinal) direction. The heat-treatment consisted of a steady increase in temperature from room temperature to 450 degrees C over a period of 4.5 hours; followed by cooling with an equivalent cooling rate. Residual strains and stresses along the longitudinal, transverse and normal directions on an as-welded and a heat-treated specimen were measured by neutron diffraction on the ENGIN-X beamline at the Isis Facility, Rutherford Laboratory, UK. Peak tensile stresses of (105 +/- 25) MPa were found in the as-welded specimen, which were reduced to (70 20) MPa after the heat-treatment. Thermal compressive stresses of (-80 +/- 20) MPa were found along the normal direction, which were not affected by the heat treatment. The use of a full-pattern Rietveld refinement for the determination of bulk strains in Zircaloy specimens is also discussed

Bilateral clubfoot in three homozygous preterm triplets.

The etiology of congenital idiopathic talipes equinovarus deformity is unclear. Studies on populations, families, and twins have suggested a genetic component. However, the mode of inheritance does not fit classic patterns. The intrauterine posture and environmental and developmental causative factors have also been associated with the deformity. Neurologic, muscular, bony, connective tissue, and vascular structures can be affected. We present the case of monochorionic triplets with bilateral congenital idiopathic talipes equinovarus deformities. To the best of our knowledge, such a presentation has not been previously described and supports a genetic etiology of congenital idiopathic talipes equinovarus deformity

Bilateral clubfoot in three homozygous preterm triplets

The etiology of congenital idiopathic talipes equinovarus deformity is unclear. Studies on populations, families, and twins have suggested a genetic component. However, the mode of inheritance does not fit classic patterns. The intrauterine posture and environmental and developmental causative factors have also been associated with the deformity. Neurologic, muscular, bony, connective tissue, and vascular structures can be affected. We present the case of monochorionic triplets with bilateral congenital idiopathic talipes equinovarus deformities. To the best of our knowledge, such a presentation has not been previously described and supports a genetic etiology of congenital idiopathic talipes equinovarus deformity

Resolution of apnea spells after sub occipital decompression in a 2-month-old infant with foramen magnum stenosis.

Background and aim Cervical canal stenosis is a rare congenital anomaly that may cause cervical myelopathy. Symptomatic congenital cervical stenosis manifests predominantly in adults. No reports have described a case in the immediate neonatal period. We here report the case of a 3-day-old neonate who presented with symptoms of cervicomedullary compression early in the neonatal period. Materials and methods The newborn was referred to our institution for investigation of hypotonia, respiratory distress and apnea spells. Shewas born by elective caesarean section at the 37thweek of gestation to nonconsanguineous parents. Apgar scoreswere 8 at 1 min and 8 at 5 min. The initial physical examination disclosedmarked neck and upper-limb hypotonia unassociated with no dysmorphisms. A thorough investigation of metabolic and genetic diseases possibly associated with hypotoniawas non diagnostic. Because the apneic eventswere related to meals, the patient underwent tests for evaluation of gastroesophageal reflux. Esophagogastroduodenoscopy showing esophagitis and hiatal hernia confirmed the diagnosis and treatment was started with the proton pump inhibitor lansoprazole. Despite treatment, the apnea spells progressively worsened. A polysomnogram documented frequent, prolonged episodes of central apnea associated or unassociatedwithmeals. Because no other cause could be found to explain why apnea and hypotonia persisted, a magnetic resonance imaging (MRI) scan of the encephalus and craniocervical junction was obtained and disclosed a foramen magnumnarrowing compressing the upper spinal cord but no other abnormality