Abstract
We investigated the doping and temperature evolutions of the optical response of Sr
3
(Ir
1−
x
Mn
x
)
2
O
7
single crystals with 0 ≤
x
≤ 0.36 by utilizing infrared spectroscopy. ...Substitution of 3
d
transition metal Mn ions into Sr
3
Ir
2
O
7
is expected to induce an insulator-to-metal transition via the decrease in the magnitude of the spin–orbit coupling and the hole doping. In sharp contrast, our data reveal the resilience of the spin–orbit coupling and the incoherent character of the charge transport. Upon Mn substitution, an incoherent in-gap excitation at about 0.25 eV appeared with the decrease in the strength of the optical transitions between the effective total angular momentum
J
eff
bands of the Ir ions. The resonance energies of the optical transitions between the
J
eff
bands which are directly proportional to the magnitude of the spin–orbit coupling hardly varied. In addition to these evolutions of the low-energy response, Mn substitution led to the emergence of a distinct high-energy optical excitation at about 1.2 eV which is larger than the resonance energies of the optical transitions between the
J
eff
bands. This observation indicates that the Mn 3
d
states are located away from the Ir 5
d
states in energy and that the large difference in the on-site energies of the transition metal ions is responsible for the incoherent charge transport and the robustness of the spin–orbit coupling. The effect of Mn substitution was also registered in the temperature dependence of the electronic response. The anomaly in the optical response of the parent compound observed at the antiferromagnetic transition temperature is notably suppressed in the Mn-doped compounds despite the persistence of the long-range antiferromagnetic ordering. The suppression of the spin-charge coupling could be related to charge disproportionation of the Ir ions.
This study was conducted to investigate the inhibitory effects of the cell‐free culture supernatant of Lactobacillus curvatus Wikim 38 (LC38‐CS) on RANKL‐induced osteoclast differentiation and bone ...loss in a mice model of ovariectomy‐induced post‐menopausal osteoporosis. LC38‐CS inhibited the RANKL‐induced differentiation of bone marrow‐derived macrophages (BMDMs) into osteoclasts in a dose‐dependent manner. F‐actin ring formation and bone resorption were also reduced by LC38‐CS treatment of RANKL‐treated BMDMs. In addition, LC38‐CS decreased the RANKL‐induced activation of the TRAF6/NF‐κB/MAPKs axis at the early stage and the expression of osteoclastogenesis‐related genes in BMDMs treated with RANKL. PRMT1 and ADMA levels, new biomarkers for osteoclastogenesis, were decreased by LC38‐CS treatment. The administration of LC38‐CS increased bone volume and bone mineral density in ovariectomized mice in μ‐CT analysis. These findings suggest that LC38‐CS inhibited RANKL‐induced osteoclast differentiation by the downregulation of molecular mechanisms and exerted anti‐osteoporotic effects.
Significance and Impact of the Study: Half of women older than 50 years will experience an osteoporosis‐related fracture in their lifetime, and thus novel therapies are needed to combat post‐menopausal bone loss. Recent studies suggest an important role for microbiota in regulating bone health. This study proposes that the administration of postbiotic of Lactobacillus curvatus Wikim 38, may be a therapeutic candidate for destructive bone diseases.
This retrospective study investigated the nature and severity of venom-induced consumption coagulopathy (VICC) and determined the clotting factors involved in VICC in patients after envenomation by ...South Korea's snakes. Additionally, we studied the effectiveness of antivenom for the treatment of VICC after envenomation.
Included patients were divided into three groups according to the severity of VICC (no VICC, partial VICC, and complete VICC). Data, including changes in coagulation parameters during hospitalization and clotting factors at presentation, were collected and analyzed.
One hundred nineteen patients who presented at our emergency department within 3 h after snake envenomation were included. VICC developed in 34 patients (27 patients with partial VICC and 7 patients with complete VICC). Two of 34 patients with VICC required blood transfusions. Five patients with complete VICC had an undetectable fibrinogen concentration at presentation. Three patients with complete VICC had an unmeasurable INR and aPTT within 24 h. The median times of the most extreme values were 10 h for INR, 12 h for aPTT, and 16 h for fibrinogen after presentation in the VICC group. The D-dimer concentration peaked at a median of 63.5 h after presentation. The activities of factors II and X were significantly reduced in the complete VICC group (factor II: 88 (84-99.3)% in the non-VICC group vs. 69 (49.5-83.5)% in the complete VICC group; factor X:94 (83-102) in the non-VICC group vs. 70 (66.5-79.8)% in the complete VICC group), while there was no difference in factor V activity at presentation. The time from bite to first antivenom administration did not correlate with the time course and most extreme concentrations for fibrinogen and D-dimer within the VICC groups.
VICC occurs in approximately one-quarter of snakebite patients in South Korea; however, VICC itself does not appear to lead to clinical deterioration. Fibrinogen is an early diagnostic maker for complete VICC. Clotting factors II and X are involved in VICC. Future investigations should explore the mechanism of VICC from Korean snakebites and the effect of antivenom on VICC.
Pneumocystis jiroveci pneumonia (PJP) is associated with high morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Little is known about PJP infections after HSCT because of ...the rarity of disease given routine prophylaxis. We report the results of a Center for International Blood and Marrow Transplant Research study evaluating the incidence, timing, prophylaxis agents, risk factors and mortality of PJP after autologous (auto) and allogeneic (allo) HSCT. Between 1995 and 2005, 0.63% allo recipients and 0.28% auto recipients of first HSCT developed PJP. Cases occurred as early as 30 days to beyond a year after allo HSCT. A nested case cohort analysis with supplemental data (n=68 allo cases, n=111 allo controls) revealed that risk factors for PJP infection included lymphopenia and mismatch after HSCT. After allo or auto HSCT, overall survival was significantly poorer among cases vs controls (P=0.0004). After controlling for significant variables, the proportional hazards model revealed that PJP cases were 6.87 times more likely to die vs matched controls (P<0.0001). We conclude PJP infection is rare after HSCT but is associated with high mortality. Factors associated with GVHD and with poor immune reconstitution are among the risk factors for PJP and suggest that protracted prophylaxis for PJP in high-risk HSCT recipients may improve outcomes.
It is anticipated that more than 75 Mb/s per subscriber is required for the convergence service such as triple-play service (TPS). Among several types of high-speed access network technologies, ...wavelength-division-multiplexing passive optical network (WDM-PON) is the most favorable for the required bandwidth in the near future. Furthermore, WDM technologies, such as athermal arrayed-waveguide grating (AWG) and low-cost light source, have matured enough to be applied in the access network. In this paper, the authors propose and implement a WDM-PON system as a platform for TPS. The system employs an amplified spontaneous emission (ASE)-injected Fabry-Pe/spl acute/rot laser diode scheme. It has 32 channels of 125 Mb/s and adopts Ethernet as Layer 2. Multicast and virtual local area network features are used for the integration of services such as Internet protocol high-definition broadcast, voice-over Internet protocol, video on demand, and video telephone. The services were demonstrated using the WDM-PON system.
Most types of cancers are made up of heterogeneous mixtures of genetically distinct subclones. In particular, acute myeloid leukemia (AML) has been shown to undergo substantial clonal evolution over ...the course of the disease. AML tends to harbor fewer mutations than solid tumors, making it challenging to infer clonal structure. Here, we present a 9-year, whole-exome sequencing study of a single case at 12 time points, from the initial diagnosis until a fourth relapse, including 6 remission samples in between. To the best of our knowledge, it covers the longest time span of any data set of its kind. We used these time series data to track the hierarchy and order of variant acquisition, and subsequently analyzed the evolution of somatic variants to infer clonal structure. From this, we postulate the development and extinction of subclones, as well as their anticorrelated expansion via varying drug responses. In particular, we show that new subclones started appearing after the first complete remission. The presence and absence of different subclones during remission and relapses implies differing drug responses among subclones. Our study shows that time series analysis contrasting remission and relapse periods provides a much more comprehensive view of clonal structure and evolution.
The breaking of orbital degeneracy on a transition metal cation and the resulting unequal electronic occupations of these orbitals provide a powerful lever over electron density and spin ordering in ...metal oxides. Here, we use ab initio calculations to show that reversibly modulating the orbital populations on Mn atoms can be achieved at ferroelectric/manganite interfaces by the presence of ferroelectric polarization on the nanoscale. The change in orbital occupation can be as large as 10%, greatly exceeding that of bulk manganites. This reversible orbital splitting is in large part controlled by the propagation of ferroelectric polar displacements into the interfacial region, a structural motif absent in the bulk and unique to the interface. We use epitaxial thin film growth and scanning transmission electron microscopy to verify this key interfacial polar distortion and discuss the potential of reversible control of orbital polarization via nanoscale ferroelectrics.
Status of LAMPS at RAON Hong, B.; Ahn, D.S.; Ahn, J.K. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
August 2023, 2023-08-00, Letnik:
541
Journal Article
Recenzirano
A new radioactive ion-beam accelerator facility, RAON, is under construction in Korea. Among the seven experimental systems being built, the Large Acceptance Multi-Purpose Spectrometer (LAMPS) in the ...high-energy experimental hall is the versatile detector system for nuclear physics. Its primary goal is to study the nuclear equation of state (EoS) and the symmetry energy of the compressed nuclear matter, which should be essential to understand the effective nuclear interactions and structure of the astrophysical objects like neutron stars. The basic LAMPS system consists of the beam diagnostic elements such as the starting counters and beam drift chambers, the time-projection chamber, the barrel and forward time-of-flight systems, the forward neutron detector array, and the superconducting solenoid magnet. In this paper the overview of the present status of each detector component for LAMPS will be given with some prospects.
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