Threshold of photoelectron emission from CNx films deposited at room temperature and at 500 °C

The threshold of photoelectron emission was measured for amorphous CNx films deposited at room temperature (RT) and at 500 °C. The x values of the films deposited at RT and at 500 °C by magnetron sputtering of a graphite target in a mixed N2/Ar gas were 0.6 and 0.3, respectively. Ratios of the sp2- to sp3-hybridized components of both C and N for the film deposited at 500 °C were larger by 4 times than those for the film deposited at RT. The onsets of the electron emission by photon irradiation were 5.0 and 4.7 eV for the films deposited at RT and at 500 °C, respectively

Method for Identifying Type of Eddy-Current Displacement Sensor

Eddy-current (EC) displacement sensors are used in a device for measuring the shaft vibration of turbines. An EC displacement sensor is composed of a sensor probe and an impedance/output voltage (Z/V) converter. In a power plant in the U. S., the type of the sensor probe and the displacement from the turbine shaft to the tip of the sensor probe (displacement x) are not controlled. For this reason, when only the Z/V converter breaks down, the plant is stopped and dismantled, and both the Z/V converter and the sensor probe are replaced. This results in two problems, i.e., the unstable supply of electric power when the power plant is stopped and the high cost of dismantling the plant. If both the type of the sensor probe and x are identified during turbine operation, the aforementioned problems could be solved. In this paper, we describe that the three types of the sensor probe and x can be identified by comparing the measured the maximum quality factor Q(EC) (max) and frequency f(o) at Q(EC) (max) with the Q(EC) (max) versus f(o) characteristics of sensor probes.ArticleIEEE TRANSACTIONS ON MAGNETICS. 47(10):3554-3557 (2011)journal articl

Suppression of osteoclastogenesis via α2-adrenergic receptors

The sympathetic nervous system is known to regulate osteoclast development. However, the involvement of α2-adrenergic receptors (α2-ARs) in osteoclastogenesis is not well understood. In the present study, their potential role in osteoclastogenesis was investigated. Guanabenz, clonidine and xylazine were used as agonists of α2-ARs, while yohimbine and idazoxan were employed as antagonists. Using RAW264.7 pre-osteoclast and primary bone marrow cells, the mRNA expression of the osteoclast-related genes nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), tartrate-resistant acid phosphatase (TRAP) and cathepsin K was evaluated following induction with receptor activator of nuclear factor κB ligand (RANKL). TRAP staining was also conducted to assess effects on osteoclastogenesis in mouse bone marrow cells in vitro. Administration of 5-20 µM guanabenz (P<0.01, for RANKL-only treatment), 20 µM clonidine (P<0.05, for RANKL-only treatment) and 20 µM xylazine (P<0.05, for RANKL-only treatment) attenuated RANKL-induced upregulation of NFATc1, TRAP and cathepsin K mRNA. Furthermore, the reductions in these mRNAs by 10 µM guanabenz and 20 µM clonidine in the presence of RANKL were attenuated by 20 µM yohimbine or idazoxan (P<0.05). The administration of 5-20 µM guanabenz (P<0.01, for RANKL-only treatment) and 10-20 µM clonidine (P<0.05, for RANKL-only treatment) also decreased the number of TRAP-positive multi-nucleated osteoclasts. Collectively, the present study demonstrates that α2-ARs may be involved in the regulation of osteoclastogenesis

Magnetic tunnel junctions with metastable bcc Co3Mn electrodes

We studied magnetic tunnel junctions (MTJs) with a MgO(001) barrier and metastable bcc Co3Mn(001) disordered alloy electrodes. A tunnel magnetoresistance (TMR) ratio was approximately 200{250% observed at room temperature.We successfully observed the TMR ratio greater than 600% at 10 K which was higher than the past reported value of MgO-based MTJs with ultrathin bcc Co(001) electrodes. However our experimental value was still much lower than the past theoretical prediction in bcc Co/MgO/Co(001) MTJs. We discuss some differences in the bulk band structure affecting the TMR effect for bcc Co and bcc Co3Mn

Bacterial Arthritis Caused by Leptotrichia amnionii▿

Leptotrichia amnionii is an organism that rarely causes female genital tract infection. We describe a case of a male patient with arthritis on the left knee joint due to this organism

Shear stress-induced Ca2+ elevation is mediated by autocrine-acting glutamate in osteoblastic MC3T3-E1 cells

AbstractMechanical loading is an important regulatory factor in bone homeostasis. Neurotransmitters, such as glutamate and ATP, are known to be released from osteoblasts, but their roles have been less studied. In this study, we investigated the role of transmitter release in mechanotransduction. To identify from where transmitters were released, focal fluid flow was applied to a single cell of MC3T3-E1, mouse calvaria-derived osteoblastic cell line, by using a glass micropipette. Intracellular Ca2+ elevation induced by the focal shear stress was eliminated by either GdCl3, a mechanosensing channel inhibitor, or removal of extracellular Ca2+. On the other hand, the focal shear stress-induced Ca2+ elevation was also significantly suppressed by inositol triphosphate receptor antagonist or vesicular release inhibitors. These results suggest that not only mechanosensitive channel-mediated Ca2+ influx but also some autocrine transmitters are involved in mechanotransduction. Additionally, glutamate receptor antagonists, but not ATP receptor antagonist, suppressed most of the focal shear stress-induced Ca2+ elevation. Therefore, it is suggested that glutamate is released from osteoblasts following the activation of mechanosensitive Ca2+ channels and acts in an autocrine manner. The glutamate release may have a significant role in the initial event of mechanotransduction in bone tissue

S and Togari A. Effects of propranolol on bone metabolism in spontaneously hypertensive rats

ABSTRACT The effects of propranolol (PRO), a nonselective ␤-adrenergic receptor (␤-AR) antagonist with membrane-stabilizing action on bone metabolism, were examined in spontaneously hypertensive rats (SHR) showing osteoporosis with hyperactivity of the sympathetic nervous system. Treatment of SHR with PRO at 1 and 5 mg/kg p.o. for 12 weeks increased bone mass of the lumbar vertebra and proximal tibia without affecting blood pressure, but PRO at 50 and 100 mg/kg with hypotensive action did not increase bone mass. Next, the effects of PRO at 0.1, 1, and 10 mg/kg on bone status were examined in more detail. Compared with the SHR control, not only bone mass but also biomechanical parameters of strength and toughness of the lumbar vertebrae were increased in SHR treated with PRO at 0.1 and 1 mg/kg, suggesting antiosteoporotic action. PRO at 1 mg/kg statistically increased histomorphometry indices of bone formation, whereas PRO at doses of 0.1, 1, and 10 mg/kg decreased those of bone resorption. Antiosteoporotic effect of PRO is attenuated at 10 mg/kg compared with 0.1 and 1 mg/kg. In addition, treatment with timolol, a nonselective ␤-AR antagonist without membrane-stabilizing action, or butoxamine, a selective ␤2-AR antagonist, at 1 mg/kg increased bone mass in SHR. These results suggested that treatment of SHR with ␤-blockers at low dose improved bone loss and bone fragility. This antiosteoporotic effect of ␤-blockers seems to be caused by the blocking action of ␤2-AR, regardless of the membrane-stabilizing action

A Modified Hyrax-Type Expander Is Effective for Distal Bodily Movement of the Maxillary First Molar

Impaction and eruption disturbance of permanent teeth are frequently encountered in orthodontic practice. The canine teeth play an important role both functionally and esthetically. Eruption disturbance of a maxillary canine, if left untreated, can cause not only disturbed jaw movement and esthetic problems, but also root resorption of adjacent permanent teeth, and thus should be diagnosed and treated appropriately. In this report, we present a case of a patient with eruption disturbance of the maxillary left canine in which the maxillary left second molar was extracted and the maxillary left first molar was distally moved with a Hyrax-type expander (Veltri Monolateral Screw®; Leone, Firenze, Italy) designed to enable the distal movement of a unilateral first molar in order to create eruption space for the maxillary left canine, resulting in smooth distal molar movement and alignment of the left maxillary canine in the dental arch. Furthermore, the maxillary third molar was also aligned to achieve a good occlusal relationship without reducing the number of teeth