12 research outputs found
Quenching of an antiferromagnet into high resistivity states using electrical or ultrashort optical pulses
Ultra-fast dynamics, insensitivity to external magnetic fields, or absence of
magnetic stray fields are examples of properties that make antiferromagnets of
potential use in the development of spintronic devices. Similar to their
ferromagnetic counterparts, antiferromagnets can store information in the
orientations of the collective magnetic order vector. However, also in analogy
to ferromagnets, the readout magnetoresistivity signals in simple
antiferromagnetic films have been weak and the extension of the electrical
reorientation mechanism to optics has not been achieved. Here we report
reversible and reproducible quenching of an antiferromagnetic CuMnAs film by
either electrical or ultrashort optical pulses into nano-fragmented domain
states. The resulting resistivity changes approach 20\% at room temperature,
which is comparable to the giant magnetoresistance ratios in ferromagnetic
multilayers. We also obtain a signal readout by optical reflectivity. The
analog time-dependent switching and relaxation characteristics of our devices
can mimic functionality of spiking neural network components
Clinical management of large adrenal cystic lesions
The widespread use of ultrasonography and computed tomography has resulted in an increased diagnosis of large sized adrenal cysts with diameters of more than 5 cm. Most of these adrenal cystic lesions are clinically silent and are therefore often diagnosed incidentally. Since up to 7% of adrenal cysts are malignant, a careful hormonal, morpho-functional and instrumental evaluation is mandatory. In particular, functioning adrenal carcinomas or pheochromocytomas have to be ruled out. Fine needle aspiration cytology as well as examination of a punch biopsy specimen of the cystic wall are of limited value, as there is considerable overlap in cytologic and histologic features of benign and malignant adrenal cystic lesions. Immediate surgical excision is indicated in the presence of symptoms, suspicion of malignancy, increase in the size or detection of a functioning adrenal cyst. En bloc adrenalectomy, preferably by a laparoscopic approach, has become the treatment of choice
The allergic sensitization in infants with atopic eczema from different countries
No study has compared allergic sensitization patterns in infants with atopic eczema from different countries. The aim of this study was to investigate the patterns of allergic sensitization in a cohort of infants with atopic eczema participating in a multicentre, international study