219 research outputs found
Optoelectronic manifestation of the orbital angular momentum driven by chiral hopping in helical Se chains
Chiral materials have garnered significant attention in the field of
condensed matter physics. Nevertheless, the magnetic moment induced by the
chiral spatial motion of electrons in helical materials, such as elemental Te
and Se, remains inadequately understood. In this work, we investigate the
development of quantum angular momentum enforced by chirality using static and
time-dependent density functional theory calculations for an elemental Se
chain. Our findings reveal the emergence of an unconventional orbital texture
driven by the chiral geometry, giving rise to a non-vanishing current-induced
orbital moment. By incorporating spin-orbit coupling, we demonstrate that a
current-induced spin accumulation arises in the chiral chain, which
fundamentally differs from the conventional Edelstein effect. Furthermore, we
demonstrate the optoelectronic detection of the orbital angular momentum in the
chiral Se chain, providing a conceptually novel alternative to the interband
Berry curvature, which is ill-defined in low dimensions.Comment: 24 pages, 4 figure
Phenylalanine ammonia-lyase expression and pyranocoumarin accumulation in Angelica gigas plantlets exposed to light-emitting diodes
Angelica gigas (Dang Gui) is an important medicinal plant. In this study, we examined the accumulation of pyranocoumarin (decursin and decursinol angelate) and the expression of phenylalanine ammonia-lyase (PAL) in Korean angelica plantlet grown under different light-emitting diodes (LEDs) (red, orange, green, blue, and white). Three weeks after LED exposure (WAE), the transcript levels of phenylalanine ammonia-lyase mRNA in seedlings grown under orange LEDs were 4-, 18-, and 7-fold higher than those in seedlings grown under green, blue, and white LEDs, respectively. The decursinol angelate content was almost double than the decursin content. The highest levels of decursin (3.2 mg/g dry weight) and decursinol angelate (6 mg/g dry weight) were detected in plants grown under orange LEDs, at 2 WAE. Therefore, we suggest that orange LEDs may affect decursin and decursinol angelate accumulation. The findings of this study could help to determine an effective strategy for producing secondary metabolites in A. gigas using LED technology
Spatial Analysis of Subway Ridership: Rainfall and Ridership
In-vehicle congestion of the urban railway system is the most important indicator to reflect the operation state of the urban railway. To provide the good service quality of urban railway, the crowdedness of the urban railway should be managed appropriately. The weather is one of the critical factors for the crowdedness. That is because even though the crowdedness of the urban railway is the same, passengers feel more uncomfortable in rainy weather condition. Indeed if specific sections and stations suddenly are concentrated excessive demand, it will lead far more serious problem. Therefore, this study analysis the relationship between the number of urban railway passenger and rainfall intensity in Seoul metropolitan subway system and then conducts the spatial analysis to deduct passenger demand patterns. This study is expected to be useful base study in order to manage the congestion at the urban railway station effectively by considering the different rainfall intensity
Enhanced heat transfer is dependent on thickness of graphene films: the heat dissipation during boiling
Boiling heat transfer (BHT) is a particularly efficient heat transport method because of the latent heat associated with the process. However, the efficiency of BHT decreases significantly with increasing wall temperature when the critical heat flux (CHF) is reached. Graphene has received much recent research attention for applications in thermal engineering due to its large thermal conductivity. In this study, graphene films of various thicknesses were deposited on a heated surface, and enhancements of BHT and CHF were investigated via pool-boiling experiments. In contrast to the well-known surface effects, including improved wettability and liquid spreading due to micron-and nanometer-scale structures, nanometer-scale folded edges of graphene films provided a clue of BHT improvement and only the thermal conductivity of the graphene layer could explain the dependence of the CHF on the thickness. The large thermal conductivity of the graphene films inhibited the formation of hot spots, thereby increasing the CHF. Finally, the provided empirical model could be suitable for prediction of CHF.open111522Nsciescopu
Hemolytic Disease of the Newborn Associated with Anti-Jr(a) Alloimmunization in a Twin Pregnancy: The First Case Report in Korea
Jr(a) is a high-frequency antigen found in all ethnic groups. However, the clinical significance of the anti-Jr(a) antibody has remained controversial. Most studies have reported mild hemolytic disease of the newborn and fetus (HDNF) in Jr(a)-positive patients. Recently, fatal cases of HDNF have also been reported. We report the first case of HDNF caused by anti-Jr(a) alloimmunization in twins in Korea. A 33-yr-old nulliparous woman with no history of transfusion or amniocentesis was admitted at the 32nd week of gestation because of vaginal bleeding caused by placenta previa. Anti-Jr(a) antibodies were detected in a routine laboratory examination. An emergency cesarean section was performed at the 34th week of gestation, and 2 premature infant twins were delivered. Laboratory examination showed positive direct antiglobulin test and Jr(a+) phenotype in the red blood cells and the presence of anti-Jr(a) antibodies in the serum in both neonates. The infants underwent phototherapy for neonatal jaundice; this was followed by conservative management. They showed no further complications and were discharged on the 19th postpartum day. Preparative management to ensure the availability of Jr(a-) blood, via autologous donation, and close fetal monitoring must be performed even in cases of first pregnancy in Jr(a-) women. (Korean J Lab Med 2010;30:511-5)Arriaga F, 2009, TRANSFUSION, V49, P813, DOI 10.1111/j.1537-2995.2009.02118.xPeyrard T, 2008, TRANSFUSION, V48, P1906, DOI 10.1111/j.1537-2995.2008.01787.xROBACK JD, 2008, TECHNICAL MANUAL, P411CHUNG HJ, 2007, KOREAN J BLOOD TRANS, V18, P111Ishihara Y, 2006, FETAL DIAGN THER, V21, P269, DOI 10.1159/000091354Daniels GL, 2004, VOX SANG, V87, P304Kwon MY, 2004, TRANSFUSION, V44, P197Bellver-Pradas J, 2001, AM J OBSTET GYNECOL, V184, P75STROUP M, 1970, P 23 ANN M AM ASS BL, P86KIM DW, 1995, ELS APPL ELECT MAT, V6, P185MIYAZAKI T, 1994, VOX SANG, V66, P51OGASAWARA K, 1990, ACTA HAEMATOL JAPON, V53, P1131GARRATTY G, 1990, TRANSFUS MED REV, V4, P297NANCE SJ, 1987, TRANSFUSION, V27, P449BACON J, 1986, TRANSFUSION, V26, P543LEVENE C, 1986, TRANSFUSION, V26, P119TAKABAYASHI T, 1985, TOHOKU J EXP MED, V145, P97TOY P, 1981, VOX SANG, V41, P40ORRICK LR, 1980, AM J OBSTET GYNECOL, V137, P135NAKAJIMA H, 1978, VOX SANG, V35, P265VEDO M, 1978, TRANSFUSION, V18, P569TRITCHLER JE, 1977, TRANSFUSION, V17, P177KENDALL AG, 1976, TRANSFUSION, V16, P646
Observation of the Far-ultraviolet Continuum Background with SPEAR/FIMS
We present the general properties of the far-ultraviolet (FUV; 1370-1720A)
continuum background over most of the sky, obtained with the Spectroscopy of
Plasma Evolution from Astrophysical Radiation instrument (SPEAR, also known as
FIMS), flown aboard the STSAT-1 satellite mission. We find that the diffuse FUV
continuum intensity is well correlated with N_{HI}, 100 m, and H-alpha
intensities but anti-correlated with soft X-ray. The correlation of the diffuse
background with the direct stellar flux is weaker than the correlation with
other parameters. The continuum spectra are relatively flat. However, a weak
softening of the FUV spectra toward some sight lines, mostly at high Galactic
latitudes, is found not only in direct-stellar but also in diffuse background
spectra. The diffuse background is relatively softer that the direct stellar
spectrum. We also find that the diffuse FUV background averaged over the sky
has about the same level as the direct-stellar radiation field in the
statistical sense and a bit softer spectrum compared to direct stellar
radiation. A map of the ratio of 1400-1510A to 1560-1660A shows that the sky is
divided into roughly two parts. However, this map shows a lot of patchy
structures on small scales. The spatial variation of the hardness ratio seems
to be largely determined by the longitudinal distribution of spectral types of
stars in the Galactic plane. A correlation of the hardness ratio with the FUV
intensity at high intensities is found but an anti-correlation at low
intensities. We also find evidence that the FUV intensity distribution is
log-normal in nature.Comment: 39 pages, 26 figures, accepted for publication in ApJ
Metformin Attenuates Experimental Autoimmune Arthritis through Reciprocal Regulation of Th17/Treg Balance and Osteoclastogenesis
- …