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1.
Nat Phys ; 17(12): 1396-1401, 2021.
Article in English | MEDLINE | ID: mdl-34966439

ABSTRACT

Ultralight bosons such as axion-like particles are viable candidates for dark matter. They can form stable, macroscopic field configurations in the form of topological defects that could concentrate the dark matter density into many distinct, compact spatial regions that are small compared with the Galaxy but much larger than the Earth. Here we report the results of the search for transient signals from the domain walls of axion-like particles by using the global network of optical magnetometers for exotic (GNOME) physics searches. We search the data, consisting of correlated measurements from optical atomic magnetometers located in laboratories all over the world, for patterns of signals propagating through the network consistent with domain walls. The analysis of these data from a continuous month-long operation of GNOME finds no statistically significant signals, thus placing experimental constraints on such dark matter scenarios.

2.
Int Neurourol J ; 24(Suppl 1): S11-18, 2020 05.
Article in English | MEDLINE | ID: mdl-32482053

ABSTRACT

PURPOSE: The effects of dexmedetomidine on locomotor function and thermal hyperalgesia in sciatic nerve crush injury (SNCI) were investigated using rats. METHODS: After exposing the right sciatic nerve, the sciatic nerve was crushed for 1 minute by a surgical clip. One day after nerve injury, dexmedetomidine (5, 25, and 50 µg/kg) was directly applied to the injured sciatic nerve once a day for 14 days. Walking track analysis was used to assess locomotor function and plantar test was conducted to assess thermal pain sensitivity. Immunohistochemistry was performed to determine the expression of c-Fos in the ventrolateral periaqueductal gray (vlPAG) and paraventricular nucleus (PVN). Western blot was used to evaluate the expression level of nerve growth factor (NGF) and myelin basic protein (MBP) in the sciatic nerve. RESULTS: SNCI resulted in deterioration of locomotor function and increased thermal pain sensitivity. The level of c-Fos expression in the PVN and vlPAG was increased and the level of NGF and MBP expression in the sciatic nerve was enhanced by SNCI. Dexmedetomidine treatment improved locomotor function and upregulated expression of NGF and MBP in the sciatic nerve of SNCI. Dexmedetomidine treatment alleviated thermal hyperalgesia and downregulated expression of c-Fos in the vlPAG and PVN after SNCI. CONCLUSION: Dexmedetomidine may be used as a potential new treatment drug for recovery of locomotion and control of pain in peripheral nerve injury.

3.
Data Brief ; 30: 105652, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32395596

ABSTRACT

This article presents data obtained from the atomic force microscopy (AFM) images of ultrathin high-k hydrocarbon (HC) films. The high-k HC films were synthesized on Si(100) wafers at various growth temperatures by using inductively-coupled plasma chemical vapor deposition with CH4 gas and a gas mixture consisting of 10% H2 and 90% Ar. The AFM images were obtained by tapping mode. The AFM results provide the surface topography, roughness, and thickness of the HC films as a function of growth temperature, which are essential data for high-k gate dielectrics of metal-insulator-semiconductor device applications. This data article is related to the article entitled, "Novel high-k gate dielectric properties of ultrathin hydrocarbon films for next-generation metal-insulator-semiconductor devices" (Kim et al., 2020) [1].

4.
Nanomicro Lett ; 12(1): 172, 2020 Aug 25.
Article in English | MEDLINE | ID: mdl-34138153

ABSTRACT

A controllable approach that combines surface plasmon resonance and two-dimensional (2D) graphene/MoS2 heterojunction has not been implemented despite its potential for efficient photoelectrochemical (PEC) water splitting. In this study, plasmonic Ag-decorated 2D MoS2 nanosheets were vertically grown on graphene substrates in a practical large-scale manner through metalorganic chemical vapor deposition of MoS2 and thermal evaporation of Ag. The plasmonic Ag-decorated MoS2 nanosheets on graphene yielded up to 10 times higher photo-to-dark current ratio than MoS2 nanosheets on indium tin oxide. The significantly enhanced PEC activity could be attributed to the synergetic effects of SPR and favorable graphene/2D MoS2 heterojunction. Plasmonic Ag nanoparticles not only increased visible-light and near-infrared absorption of 2D MoS2, but also induced highly amplified local electric field intensity in 2D MoS2. In addition, the vertically aligned 2D MoS2 on graphene acted as a desirable heterostructure for efficient separation and transportation of photo-generated carriers. This study provides a promising path for exploiting the full potential of 2D MoS2 for practical large-scale and efficient PEC water-splitting applications.

5.
Int J Mol Sci ; 21(1)2019 Dec 18.
Article in English | MEDLINE | ID: mdl-31861329

ABSTRACT

Nuclear receptor related-1 (Nurr1) protein performs a crucial role in hippocampal neural stem cell (hNSC) development as well as cognitive functions. We previously demonstrated that the pharmacological stimulation of Nurr1 by amodiaquine (AQ) promotes spatial memory by enhancing adult hippocampal neurogenesis. However, the role of Nurr1 in the cell cycle regulation of the adult hippocampus has not been investigated. This study aimed to examine changes in the cell cycle-related molecules involved in adult hippocampal neurogenesis induced by Nurr1 pharmacological stimulation. Fluorescence-activated cell sorting (FACS) analysis showed that AQ improved the progression of cell cycle from G0/G1 to S phase in a dose-dependent manner, and MEK1 or PI3K inhibitors attenuated this progression. In addition, AQ treatment increased the expression of cell proliferation markers MCM5 and PCNA, and transcription factor E2F1. Furthermore, pharmacological stimulation of Nurr1 by AQ increased the expression levels of positive cell cycle regulators such as cyclin A and cyclin-dependent kinases (CDK) 2. In contrast, levels of CDK inhibitors p27KIP1 and p57KIP2 were reduced upon treatment with AQ. Similar to the in vitro results, RT-qPCR analysis of AQ-administered mice brains revealed an increase in the levels of markers of cell cycle progression, PCNA, MCM5, and Cdc25a. Finally, AQ administration resulted in decreased p27KIP1 and increased CDK2 levels in the dentate gyrus of the mouse hippocampus, as quantified immunohistochemically. Our results demonstrate that the pharmacological stimulation of Nurr1 in adult hNSCs by AQ promotes the cell cycle by modulating cell cycle-related molecules.


Subject(s)
Adult Stem Cells/metabolism , Cell Cycle/genetics , Hippocampus/cytology , Neural Stem Cells/metabolism , Nuclear Receptor Subfamily 4, Group A, Member 2/genetics , Adult Stem Cells/drug effects , Amodiaquine/pharmacology , Animals , Biomarkers , Cell Cycle/drug effects , Cell Proliferation , Dentate Gyrus/metabolism , E2F1 Transcription Factor/genetics , E2F1 Transcription Factor/metabolism , Gene Expression Regulation , Humans , Immunohistochemistry , Male , Mice , Neural Stem Cells/drug effects , Neurogenesis/drug effects , Neurogenesis/genetics , Nuclear Receptor Subfamily 4, Group A, Member 2/metabolism , Rats
6.
Am J Physiol Renal Physiol ; 317(3): F670-F682, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31339773

ABSTRACT

The intratubular renin-angiotensin system (RAS) is thought to play an essential role in hypertensive renal disease, but information regarding sex-related differences in this system is limited. The present study investigated sex differences in the intratubular RAS in two-kidney, one-clip (2K1C) rats. A 2.5-mm clip was placed on the left renal artery of Sprague-Dawley rats, and rats were euthanized 3 or 5 wk after the operation. Systolic blood pressure increased in 2K1C rats in both sexes but was significantly higher in male rats than in female rats, and an antihypertensive effect was not observed in 2K1C ovariectomized (OVX) female rats. Compared with male 2K1C rats, intratubular angiotensin-converting enzyme (ACE) and ANG II were repressed, and intratubular ACE2, angiotensin (1-7), and Mas receptor were increased in both kidneys in female 2K1C rats 5 wk after surgery. Comparison with male and female rats and intratubular mRNA levels of ACE and ANG II type 1 receptor were augmented in OVX female rats, regardless of the clipping surgery 3 wk postoperation. ANG II type 2 receptor was upregulated in female rats with or without OVX; thus, the ANG II type 1-to-type 2 receptor ratio was higher in male rats than in female rats. In conclusion, female rats were protected from hypertensive renal and cardiac injury after renal artery clipping. An increase in the intratubular nonclassic RAS [ACE2/angiotensin (1-7)/Mas receptor] and a decrease in the ANG II type 1-to-type 2 receptor ratio could limit the adverse effects of the classic RAS during renovascular hypertension in female rats, and estrogen is suggested to play a primary role in the regulation of intratubular RAS components.


Subject(s)
Blood Pressure , Estrogens/metabolism , Hypertension/metabolism , Kidney Tubules/metabolism , Renal Artery/surgery , Renin-Angiotensin System , Angiotensin I/metabolism , Angiotensin II/metabolism , Angiotensin-Converting Enzyme 2 , Animals , Constriction , Disease Models, Animal , Female , Hypertension/etiology , Hypertension/genetics , Hypertension/physiopathology , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/metabolism , Hypertrophy, Left Ventricular/physiopathology , Kidney Tubules/physiopathology , Macrophages/metabolism , Male , Ovariectomy , Peptide Fragments/metabolism , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Proto-Oncogene Mas , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Rats, Sprague-Dawley , Receptor, Angiotensin, Type 1/genetics , Receptor, Angiotensin, Type 1/metabolism , Receptor, Angiotensin, Type 2/metabolism , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Renal Artery/physiopathology , Sex Factors , Signal Transduction
7.
Nat Commun ; 9(1): 3788, 2018 09 17.
Article in English | MEDLINE | ID: mdl-30224700

ABSTRACT

Current-induced magnetic domain wall (DW) motion is an important operating principle of spintronic devices. Injected current generates spin torques (STs) on the DWs in two ways. One is the spin transfer from magnetic domains to the walls by the current flowing in the magnet. Current flow in attached heavy metals also generates another ST because of the spin-Hall effect. Both phenomena explain the wall motions well; therefore, their respective contribution is an important issue. Here, we show the simultaneous measurement of both torques by using magnetic facet domains that form mountain-shaped domains with straight walls. When the STs and the external magnetic field push the walls in opposite directions, the walls should have equilibrium angles to create balanced states. Such angles can be modulated by an additional in-plane magnetic field. Angle measurements distinguish the STs because each torque has a distinct mechanism related to the DW structure.

8.
ACS Appl Mater Interfaces ; 9(25): 21406-21412, 2017 Jun 28.
Article in English | MEDLINE | ID: mdl-28573859

ABSTRACT

We present a simple, ultrasonic vibration-assisted lift-off-based patterning approach for graphene and graphene-Ag nanowire (NW) hybrid films. A 20 µm width pattern with uniform and smooth pattern edges was neatly defined on various rigid and flexible substrates. The patterned graphene-Ag NW electrodes showed a low sheet resistance of 19 Ω/sq with a high transmittance of 93% at 550 nm, a robust stability against oxidation, and a high reliability under a bending test. The electrodes also exhibited markedly higher performance than that of commercial fluorine-doped tin oxide electrodes for dye-sensitized solar cells. Given its low-cost, high throughput, and nondamaging effect, this simple and reliable patterning approach stimulates the practical applications of graphene-based flexible transparent electrodes in soft electronic and optoelectronic devices.

9.
Sci Rep ; 6: 25391, 2016 05 06.
Article in English | MEDLINE | ID: mdl-27151368

ABSTRACT

In spintronic devices consisting of ferromagnetic/nonmagnetic systems, the ferromagnet-induced magnetic moment in the adjacent nonmagnetic material significantly influences the spin transport properties. In this study, such magnetic proximity effect in a Pd/Co/Pd trilayer system is investigated by x-ray magnetic circular dichroism and x-ray resonant magnetic reflectivity, which enables magnetic characterizations with element and depth resolution. We observe that the total Pd magnetic moments induced at the top Co/Pd interface are significantly larger than the Pd moments at the bottom Pd/Co interface, whereas transmission electron microscopy and reflectivity analysis indicate the two interfaces are nearly identical structurally. Such asymmetry in magnetic proximity effects could be important for understanding spin transport characteristics in ferromagnetic/nonmagnetic systems and its potential application to spin devices.

11.
Korean J Anesthesiol ; 61(5): 428-30, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22148093

ABSTRACT

Rett syndrome is a neurological disease that occurs only in females and it manifests with mental retardation, seizures, movement disorders, autistic behavior and abnormal breathing. A 19-year-old female with Rett syndrome underwent ophthalmologic surgery under general anesthesia at our institution. Airway control was difficult due to her limited mouth opening. We recommend that anesthesiologists should have proper knowledge about this disease and the patients to avoid the complications and problems that can be encountered during the perioperative period.

12.
J Anesth ; 24(2): 287-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20084407

ABSTRACT

This report describes a rare case of acute life-threatening stridor that was due to membranous obstructive Candida tracheitis, and this condition occurred after long-term endotracheal intubation and tracheostomy. An obstructive membrane was found 2 cm above the carina by bronchofiberscopy. The removal of the membrane resulted in the complete relief of the airway obstruction.


Subject(s)
Airway Obstruction/etiology , Candidiasis , Intubation, Intratracheal/adverse effects , Tracheitis/microbiology , Tracheostomy/adverse effects , Aged , Airway Obstruction/surgery , Bronchoscopy , Female , Humans , Tracheitis/surgery , Treatment Outcome
13.
Anesthesiology ; 111(3): 556-60, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19672184

ABSTRACT

BACKGROUND: Malpositioning of the endotracheal tube within the airway leads to serious complications such as endobronchial intubation. Prediction of the correct depth of an endotracheal tube is important and should be individualized. The manubriosternal joint (MSJ) is on the same horizontal plane with the tracheal carina. We compared the straight length from the upper incisor to the MSJ in the fully extended position (incisor-MSJ extension length) with the length from the upper incisor to the carina after intubation with a flexible fiberoptic bronchoscope through the endotracheal tube in the neutral position (incisor-carina neutral length). METHODS: One hundred adults and 50 children were studied. Induction of anesthesia was achieved with 1.5 mg/kg propofol and 0.6 mg/kg rocuronium IV. The incisor-MSJ extension length was measured after adequate mask ventilation. After intubation, the endotracheal tube was positioned properly at the upper incisor teeth, and the incisor-carina neutral length was measured with the fiberoptic bronchoscope at the carina. RESULTS: The correlation between the incisor-MSJ extension length and the incisor-carina neutral length is significant (P < 0.001) in both adults and children. A formula for the regression line in adults (children) can be obtained as the incisor-carina neutral length (cm) = 0.868 (1.009) x the incisor-MSJ extension length (cm) + 4.260 (0.468) with a high coefficient of determination; r(2) = 0.88 (0.98). CONCLUSIONS: The airway length from the upper incisor to the carina in the neutral position can be predicted by the straight length from the upper incisor to the MSJ in the fully extended position.


Subject(s)
Intubation, Intratracheal/instrumentation , Point-of-Care Systems , Respiratory System/anatomy & histology , Adolescent , Adult , Aged , Aging/physiology , Algorithms , Androstanols , Anesthesia, General , Anesthetics, Intravenous , Bronchoscopes , Bronchoscopy , Child , Child, Preschool , Female , Humans , Incisor/anatomy & histology , Infant , Joints/anatomy & histology , Male , Manubrium/anatomy & histology , Middle Aged , Neuromuscular Nondepolarizing Agents , Optical Fibers , Predictive Value of Tests , Propofol , Rocuronium , Trachea/anatomy & histology , Young Adult
14.
Lasers Med Sci ; 24(2): 214-22, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18386092

ABSTRACT

The use of light for medical treatment has been studied previously. In this study, we examined the effect of light from a red light-emitting diode on osteogenic differentiation of mouse mesenchymal stem cells (D1 cells) which were cultured in the presence of osteogenic differentiation medium (ODM) for 3 days, then exposed to a red light-emitting diode (LED) light of 647 nm wavelength once for 10 s, 30 s or 90 s with radiation energies of 0.093 J, 0.279 J and 0.836 J, respectively. D1 cells in the presence of ODM differentiated into osteoblasts, and this process was enhanced on exposure to LED light in ODM medium. This effect was confirmed by increased Alizarin red staining, higher alkaline phosphatase (ALP) activity, higher mRNA expressions of osteocalcin, collagen type I, osteopontin and Runt-related transcription factor2 (Runx2), and higher levels by reverse transcriptase-polymerase chain reaction (RT-PCR) and by increased immunofluorescence staining against cluster of differentiation 44 (CD44) by immunofluorescence microscopy, confocal microscopy and flow cytometric analysis. These data suggest that osteogenic differentiation of mesenchymal stem cells (MSCs) in ODM is enhanced by LED light exposure.


Subject(s)
Cell Differentiation/radiation effects , Lasers, Semiconductor , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/radiation effects , Osteoblasts/radiation effects , Phototherapy , Animals , Calcification, Physiologic/radiation effects , Cell Culture Techniques , Mice , Osteoblasts/cytology , Osteogenesis/radiation effects
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