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Using a molecular beam epitaxy technique, we experimentally demonstrate a multiferroic heterostructure consisting of metastable ferromagnetic Co 3 Mn on piezoelectric Pb(Mg 1 / 3 Nb 2 / 3 )O 3 –PbTiO 3 (PMN-PT). Inserting a 2-nm-thick Fe layer between Co 3 Mn and PMN-PT(001) allows the formation of bcc Co 3 Mn layers even at an extremely low growth temperature of ∼ 80 ° C. Upon increasing this temperature to 200 ° C, a bcc Co 3 Mn/Fe/PMN-PT(001) multiferroic heterostructure with a relatively large saturation magnetization of ∼ 1680 kA/m and an atomically flat interface is obtained, resulting in an obvious converse magnetoelectric (CME) effect. The large CME effect originates mainly from the strain-induced modulation of the magnetic anisotropy energy, supported by the first-principles calculations. [ABSTRACT FROM AUTHOR]

Using artificially controlled ferromagnet (FM)–semiconductor (SC) interfaces, we study the decay of the nonlocal spin signals with increasing temperature in SC-based lateral spin-valve devices. When more than five atomic layers of Fe are inserted at the FM/SC interfaces, the temperature-dependent spin injection/detection efficiency (P inj / det ) can be interpreted in terms of the T 3 2 law, meaning a model of the thermally excited spin waves in the FM electrodes. For the FM/SC interfaces with the insufficient insertion of Fe atomic layers, on the other hand, the decay of P inj / det is more rapid than the T 3 2 curve. Using magneto-optical Kerr effect measurements, we find that more than five atomic layers of Fe inserted between FM and SC enable us to enhance the ferromagnetic nature of the FM/SC heterointerfaces. Thus, the ferromagnetism in the ultra-thin FM layer just on top of SC is strongly related to the temperature-dependent nonlocal spin transport in SC-based lateral spin-valve devices. We propose that the sufficient ferromagnetism near the FM/SC interface is essential for high-performance FM–SC hybrid devices above room temperature. [ABSTRACT FROM AUTHOR]

We experimentally show a giant magnetoelectric (ME) effect at room temperature in an interfacial multiferroic heterostructure consisting of L21-ordered Co2FeSi and Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT). Molecular beam epitaxy growth at 400 °C enables us to obtain epitaxial and L21-ordered Co2FeSi films on PMN-PT(001). For the epitaxial Co2FeSi/PMN-PT heterostructure, the remanent magnetization state can be largely modulated by varying electric fields. We note that the room-temperature ME coupling coefficient (α) is estimated to be 6.0–6.3 × 10 − 6 s/m, comparable to the highest α value reported previously. Nonvolatile and repeatable magnetization changes in remanent states are also demonstrated. These results will pave the way for room-temperature electric-field control of the magnetization of half-metallic Heusler alloys in high-performance spintronic devices. [ABSTRACT FROM AUTHOR]

Magnetic properties of Co film in Pt/Co/α-Cr2O3/Pt/α-Al2O3 structure were investigated. Co layer thickness tCo dependence of perpendicular magnetic anisotropy energy density K reveals that the bulk magnetic anisotropy plays an important role in the system in addition to the interfacial anisotropy. Damping constant α monotonically increases with the decrease of tCo but not proportionally to 1/tCo. Both K and α increase with the increase of Pt layer thickness tPt from 3 nm to 5 nm and keeps almost constant in the tPt range between 5 nm to 20 nm. These results are of importance to understand the magnetization switching behavior driven by the magneto-electric (ME) effect as well as to design the spintronics device using the ME effect. [ABSTRACT FROM AUTHOR]

Rodent incisors exhibit pigmentation on their labial surfaces. Although previous studies have shown that this pigment is composed of iron, the existence of other elements has not been investigated. This study found that the lower incisors of CD61, also known as integrin β3, null mice (CD61-/-) lacked pigmentation. Although ameloblasts differentiated and formed enamel normally, no ferric ion accumulation was observed in maturation-stage ameloblasts in CD61-/- mice. Surface elements of control and CD61-/- lower incisors were compared by x-ray photoelectron spectroscopy (XPS). XPS analysis detected C, Ca, N, O, and P on the labial surfaces of lower incisors of both mice, whereas Fe was detected only in control samples. No peak of non-ferrous metal or other element was detected in either group. Quantitative RT-PCR analysis of 18 iron-transportation-related genes with mRNA from maturation-stage ameloblasts and ALC, a pre-ameloblastic cell line, was performed. The results suggested that CD61 regulates the expressions of Slc11a2 and Slc40a1, both of which are involved in iron transportation in epithelial tissues. These results suggested that the pigment on the labial surface of mouse incisors is composed of Fe and that both anemia and reduction of iron-transporting proteins may cause the loss of pigmentation in CD61-/- mice. [ABSTRACT FROM PUBLISHER]

Abstract: This case report presents a case that underwent orthognathic treatment with anterior segmental osteotomies on both jaws. The patient was a 26-year-old female with maxillary protrusion, lip incompetence with an everted vermilion border. The overbite was +1.0mm, overjet +1.0mm. The pre-surgical orthodontic treatment included the extraction of the four first premolars and a multi-bracket treatment was started. After 12 months of pre-surgical orthodontic treatment, both the anterior maxillary and the anterior mandibular segments were retracted surgically by 5.5mm. The total treatment period was 18 months. An anterior segmental osteotomy can induce the remarkable structural changes for bimaxillary lip protrusion patients. [Copyright &y& Elsevier]

Abstract: We studied the healing process of mandibular closed fractures in osteoporotic rats using specific antibodies to bone morphogenetic protein-2 (BMP-2) and tumour necrosis factor-α (TNF-α). We confirmed the osteoporosis in rats after oophorectomy by micro-CT, and then caused unilateral closed fractures in the mandible and monitored the healing process after 7, 14, 21, and 28 days. Data were compared simultaneously with those from a group of rats that had a sham operation. During healing of the fracture in the osteoporotic group there was a prolonged phase of endochondral ossification, with an increased number of osteoclasts (p <0.01). Expressions of BMP-2 and TNFα were more pronounced in the osteoporotic group and there was an increase in the number of osteoblasts and TNFα+ cells compared with the normal control (p <0.01). BMP-2 was related to the differentiation of osteoblasts and the higher values of TNFα were correlated with the up-regulation of osteoclasts during the prolonged phase of bone turnover. We conclude that the healing of fractures in osteoporotic bone is delayed about a week compared with controls. In the healing of fractures in osteoporotic bone, there were more osteoblasts and osteoclasts but there was a predominance of osteoclasts probably induced by TNFα. The prolonged phase of bone turnover with osteoclast predominance in the osteoporotic group is suggestive of the cause of delay in the healing of the fracture. [Copyright &y& Elsevier]

We describe a case of lymphoepithelial lesion of the parotid gland, also known as salivary lymphoepithelial lesion. Lymphoepithelial lesions are usually seen in conjunction with autoimmune disease of the salivary glands and these lesions do not always remain benign. Our case consisted of two masses that had different imaging features. Moreover, we could investigate the changes of the size and internal architecture on imaging due to the postponement of surgical intervention on the masses. At review 6 months later, the size of the masses had increased. The aims of this paper were to: (1) investigate the contribution of gray-scale sonography, power Doppler sonography, magnetic resonance imaging, and computed tomography to the diagnosis; and (2) consider the appropriate imaging modality to follow-up this case to monitor for recurrence or malignant transformation.Dentomaxillofacial Radiology (2002) 31, 198–203 DOI: 10.1038/sj/dmfr/4600690 [ABSTRACT FROM AUTHOR]