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Hereditary neuropathy with liability to pressure palsies (HNPP) is well defined in adults, but its clinical and electrophysiological features in childhood have not been well characterized. We describe a case of HNPP in a child with the unique electrophysiological presentation, affecting only one upper extremity. [ABSTRACT FROM AUTHOR]

We present high-resolution (R ~ 45 000) profiles of 14 diffuse interstellar bands in the ~1.45 to ~2.45 µm range based on spectra obtained with the Immersion Grating INfrared Spectrograph at the McDonald Observatory. The revised list of diffuse bands with accurately estimated rest wavelengths includes six new features. The diffuse band at 15 268.2 Å demonstrates a very symmetric profile shape and thus can serve as a reference for finding the 'interstellar correction' to the rest wavelength frame in the H range, which suffers from a lack of known atomic/molecular lines. [ABSTRACT FROM AUTHOR]

Background/Aims: Endoscopic therapy with endoscopic retrograde cholangiopancreatography (ERCP) has been suggested as an effective diagnostic and therapeutic tool for biliary and pancreatic disorders during pregnancy. In this report, we describe our experiences with pancreatobiliary endoscopic procedures during pregnancy. Methods: We reviewed ERCP and endoscopic ultrasonography (EUS) procedures that were performed at a single tertiary care referral center between January 2002 and October 2013. Medical records were reviewed for the procedure indication, the duration of fluoroscopy, postprocedure complications, etc. Pregnancy outcomes and fetal complications were identified by chart review and phone calls to patients. Results: A total of 10 ERCPs and five EUSs were performed in 13 pregnant patients: four of whom underwent the procedure in the first trimester, eight in the second trimester, and one in the third trimester. Indications for endoscopic therapy included gallstone pancreatitis, obstructive jaundice with common bile duct (CBD) stone, asymptomatic CBD stone, pancreatic cyst, choledochal cyst, and acute cholecystitis. Only one patient had a complication, which was postprocedural hyperamylasemia. Two patients underwent an artificial abortion, one according to her own decision and the other due to an adverse drug reaction. Conclusions: ERCP seems to be effective and safe for pregnant women. Additionally, EUS can be an alternative to ERCP during pregnancy. [ABSTRACT FROM AUTHOR]

The Galactic supernova remnant (SNR) IC 443 is one of the most studied core-collapse SNRs for its interaction with molecular clouds. However, the ambient molecular clouds with which IC 443 is interacting have not been thoroughly studied and remain poorly understood. Using the Five College Radio Astronomy Observatory 14 m telescope, we obtained fully sampled maps of the ~1° x 1° region toward IC 443 in the 12CO J = 1-0 and HCO+ J = 1-0 lines. In addition to the previously known molecular clouds in the velocity range υLSR = -6 to -1 km s-1 (-3 km s-1 clouds), our observations reveal two new ambient molecular cloud components: small (~1') bright clouds in υLSR = -8 to -3 km s-1 (SCs) and diffuse clouds in υLSR = +3 to +10 km s-1 (+5 km s-1 clouds). Our data also reveal the detailed kinematics of the shocked molecular gas in IC 443; however, the focus of this paper is the physical relationship between the shocked clumps and the ambient cloud components. We find strong evidence that the SCs are associated with the shocked clumps. This is supported by the positional coincidence of the SCs with shocked clumps and other tracers of shocks. Furthermore, the kinematic features of some shocked clumps suggest that these are the ablated material from the SCs upon the impact of the SNR shock. The SCs are interpreted as dense cores of parental molecular clouds that survived the destruction by the pre-supernova evolution of the progenitor star or its nearby stars. We propose that the expanding SNR shock is now impacting some of the remaining cores and the gas is being ablated and accelerated, producing the shocked molecular gas. The morphology of the +5 km s-1 clouds suggests an association with IC 443. On the other hand, the -3 km s-1 clouds show no evidence for interaction. [ABSTRACT FROM AUTHOR]

This review focuses on recent contributions in the development of the electrochemical sensors based on carbon nanotubes (CNTs). CNTs have unique mechanical and electronic properties, combined with chemical stability, and behave electrically as a metal or semiconductor, depending on their structure. For sensing applications, CNTs have many advantages such as small size with larger surface area, excellent electron transfer promoting ability when used as electrodes modifier in electrochemical reactions, and easy protein immobilization with retention of its activity for potential biosensors. CNTs play an important role in the performance of electrochemical biosensors, immunosensors, and DNA biosensors. Various methods have been developed for the design of sensors using CNTs in recent years. Herein we summarize the applications of CNTs in the construction of electrochemical sensors and biosensors along with other nanomaterials and conducting polymers. [ABSTRACT FROM AUTHOR]

In the present study, we investigated whether rosmarinic acid, which has been suggested to exhibit anti-inflammatory properties, can suppress the expressions of monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1a (MIP-1a) via the MAPK pathway in LPS-stimulated bone marrow-derived dendritic cells (BMDCs) in the presence of GM-CSF and IL-4 in media. The effects of rosmarinic acid were investigated in BMDCs with respect to the following; cytotoxicity, surface molecule expression, dextran-FITC uptake, cell migration, chemokine gene expression, and the MAPK signaling pathway. Rosmarinic acid was found to significantly inhibit the expressions of CD80, CD86, MHC class I, and MHC class II in LPS-stimulated mature BMDCs, and rosmarinic acid-treated BMDCs were found to be highly efficient with regards to antigen capture via mannose receptor-mediated endocyto-sis. In addition, rosmarinic acid reduced cell migration by inducing the expression of a specific chemokine receptor on LPS-induced mature BMDCs. Rosmarinic acid also significantly reduced the expressions of MCP-1 and MIP-1a induced by LPS in BMDCs and inhibited LPS-induced activation of MAPK and the nuclear translocation of NF-KB. These findings broaden current perspectives concerning our understanding of the immunopharmacological functions of rosmarinic acid, and have ramifications that concern the development of therapeutic drugs for the treatment of DC-related acute and chronic diseases. [ABSTRACT FROM AUTHOR]

We present BVI surface photometry of 31 dwarf galaxy candidates discovered in a deep image stack from the KMTNet Supernova Program of ∼30 square degrees centered on the nearby NGC 2784 galaxy group. Our final images have a 3σ surface brightness detection limit of mag arcsec−2. The faintest central surface brightness that we measure is mag arcsec−2. If these candidates are at the distance of NGC 2784, then they have absolute magnitudes greater than mag and effective radii larger than 170 pc. Their radial number density decreases exponentially with distance from the center of NGC 2784 until it flattens beyond a radius of 0.5 Mpc. We interpret the baseline density level to represent the background contamination and estimate that 22 of the 31 new candidates are dwarf members of the group. The candidate’s average color, , and Sérsic structural parameters are consistent with those parameters for the dwarf populations of other groups. We find that the central population of dwarfs is redder and brighter than the rest of the population. The measured faint-end slope of the luminosity function, , is steeper than that of the Local Group, but consistent with published results for other groups. Such comparisons are complicated by systematic differences among different studies, but will be simpler when the KMTNet survey, which will provide homogenous data for 15–20 groups, is completed. [ABSTRACT FROM AUTHOR]

Recent high-resolution infrared space missions have revealed supernova remnants (SNRs) of diverse morphology in infrared (IR) dust emission that are often very different from their X-ray appearance. The observed range of infrared-to-X-ray (IRX) flux ratios of SNRs is also wide. For a sample of 20 Galactic SNRs, we obtain their IR and X-ray properties and investigate the physical causes for such large differences. We find that the observed IRX flux ratios () are related to the IRX morphology, with SNRs with the largest showing anticorrelated IRX morphology. By analyzing the relation of to X-ray and IR parameters, we show that the of some SNRs agrees with theoretical ratios of SNR shocks in which dust grains are heated and destroyed by collisions with plasma particles. For the majority of SNRs, however, values are either significantly smaller or significantly larger than the theoretical ratios. The latter SNRs have relatively low dust temperatures. We discuss how the natural and/or environmental properties of SNRs could have affected the IRX flux ratios and the IRX morphology of these SNRs. We conclude that the SNRs with largest are probably located in a dense environment and that their IR emission is from dust heated by shock radiation rather than by collisions. Our result suggests that the IRX flux ratio, together with dust temperature, can be used to infer the nature of unresolved SNRs in external galaxies. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the anti-obesity effect of different concentrations of extracts of hot airdried ramie leaf (HR) and freeze-dried ramie leaf (FR) in 3T3-L1 cells and pig preadipocytes. To analyze the effect on cell proliferation, cells were treated with 25 μg/mL or 100 μg/mL HR or FR extract for 2 days. Cell differentiation was evaluated by measuring glycerol-3- phosphate dehydrogenase and lipoprotein lipase (LPL) activities and intracellular triglyceride content. Treatment with either HR or FR extracts inhibited the proliferation of 3T3-L1 cells and pig preadipocytes in a dose-dependent manner. HR extract treatment inhibited the differentiation of both cell types more effectively than FR treatment. The extent of triglyceride accumulation decreased significantly in both cells following either HR or FR treatment. Furthermore, LPL activity significantly decreased after treatment with HR or FR extract. These results indicated that HR and FR extracts may inhibit proliferation and differentiation of 3T3-L1 cells and pig preadipocytes. Further studies are needed to explore the anti-obesity effect of HR and FR extracts. [ABSTRACT FROM AUTHOR]

Objective To evaluate correlations between values of articulation tests and language tests for children with articulation disorder in Korea. Methods Data of outpatients with chief complaint of an articulation problem were retrospectively collected. Patients who underwent Urimal Test of Articulation and Phonation (U-TAP) with Assessment of Phonology and Articulation for Children (APAC), Preschool Receptive-Expressive Language Scale (PRES), or Receptive and Expressive Vocabulary Test (REVT) simultaneously were identified. Patients whose word-level percentages of correct consonants in U-TAP (UTAP_wC) were more than 2 standard deviations below the mean as diagnostic criteria for articulation disorder were selected. Those whose receptive language age (P_RLA), expressive language age (P_ELA), or combined language age (P_CLA) in PRES was delayed more than 24 months compared to their chronological age in months as diagnostic criteria for language disorder were excluded. Results Thirty-three children aged 3-6 years were enrolled retrospectively. PRES and U-TAP showed significant correlations for most of value relationships. PRES and APAC showed significant correlations for all value relationships except for receptive language age. All values of REVT were significantly correlated with all values from U-TAP, but not with any value from APAC. Articulation tests U-TAP and APAC showed significant correlations between percentages of correct consonants. Language tests PRES and REVT showed significant correlations for all value relationships. Conclusion This study suggests that articulation abilities and language abilities might be correlated in children with articulation disorder. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to enable on-line prediction of primal and commercial cut weights in Korean slaughter pigs by AutoFom III, which non-invasively scans pig carcasses early after slaughter using ultrasonic sensors. Methods: A total of 162 Landrace, Yorkshire, and Duroc (LYD) pigs and 154 LYD pigs representing the yearly Korean slaughter distribution were included in the calibration and validation dataset, respectively. Partial least squares (PLS) models were developed for prediction of the weight of deboned shoulder blade, shoulder picnic, belly, loin, and ham. In addition, AutoFom III´s ability to predict the weight of the commercial cuts of spare rib, jowl, false lean, back rib, diaphragm, and tenderloin was investigated. Each cut was manually prepared by local butchers and then recorded. Results: The cross-validated prediction accuracy (R2cv) of the calibration models for deboned shoulder blade, shoulder picnic, loin, belly, and ham ranged from 0.77 to 0.86. The R2cv for tenderloin, spare rib, diaphragm, false lean, jowl, and back rib ranged from 0.34 to 0.62. Because the R2cv of the latter commercial cuts were less than 0.65, AutoFom III was less accurate for the prediction of those cuts. The root mean squares error of cross validation calibration (RMSECV) model was comparable to the root mean squares error of prediction (RMSEP), although the RMSECV was numerically higher than RMSEP for the deboned shoulder blade and belly. Conclusion: AutoFom III predicts the weight of deboned shoulder blade, shoulder picnic, loin, belly, and ham with high accuracy, and is a suitable process analytical tool for sorting pork primals in Korea. However, AutoFom III's prediction of smaller commercial Korean cuts is less accurate, which may be attributed to the lack of anatomical reference points and the lack of a good correlation between the scanned area of the carcass and those traits. [ABSTRACT FROM AUTHOR]

We present an analysis of near-infrared, high-resolution spectroscopy toward the flat-spectrum young stellar object (YSO) ESO Hα 279a (∼1.5M⊙) in the Serpens star-forming region at a distance of 429 pc. Using the Immersion GRating INfrared Spectrometer (IGRINS; R ≈ 45,000), we detect emission lines originating from the accretion channel flow, jet, and inner disk. Specifically, we identify hydrogen Brackett series recombination, [Fe ii], [Fe iii], [Fe iv], Ca i, Na i, H2, H2O, and CO overtone emission lines. By modeling five bands of CO overtone emission lines and the symmetric double-peaked line profile for Na i emission lines, we find that ESO Hα 279a has an actively accreting Keplerian disk. From our Keplerian disk model, we find that Na i emission lines originate between 0.04 and 1.00 au, while the CO overtone emission lines are from the outer part of the disk, in the range between 0.22 and 3.00 au. The model reveals that the neutral atomic Na gas is a good tracer of the innermost region of the actively accreting disk. We derive a mass accretion rate of M⊙ yr−1 from the measured Brγ emission luminosity of 1.78(±0.31) × 1031 erg s−1. [ABSTRACT FROM AUTHOR]

Pacemaker implantation-related infective endocarditis is an uncommon, but serious complication. The estimated incidence of infection after permanent endocardial pacemaker implantation varies from 0.2% to 3%. Infective endocarditis shows a mortality rate of 30% to 35%. Conservative medical treatment without removing the pacemaker is prone to failure, and reinfection rates of 51% to 77% have been noted in patients whose pacemaker systems become infected. Therefore, diagnosis of the primary infection is particularly important because surgical removal of the pacemaker system is usually required for its treatment. We describe here an 80-year-old woman who had drug fever that could have been misdiagnosed as infective endocarditis after pacemaker implantation. [ABSTRACT FROM AUTHOR]

Conducting polymers (CPs) are a group of polymeric materials that have attracted considerable attention because of their unique electronic, chemical, and biochemical properties. This is reflected in their use in a wide range of potential applications, including light-emitting diodes, anti-static coating, electrochromic materials, solar cells, chemical sensors, biosensors, and drug-release systems. Electrochemical DNA sensors based on CPs can be used in numerous areas related to human health. This review summarizes the recent progress made in the development and use of CP-based electrochemical DNA hybridization sensors. We discuss the distinct properties of CPs with respect to their use in the immobilization of probe DNA on electrode surfaces, and we describe the immobilization techniques used for developing DNA hybridization sensors together with the various transduction methods employed. In the concluding part of this review, we present some of the challenges faced in the use of CP-based DNA hybridization sensors, as well as a future perspective. [ABSTRACT FROM AUTHOR]

T-lymphoblastic lymphoma (T-LBL) is a rare form of aggressive non-Hodgkin's lymphoma. The standard approach for management of T-LBL involves intensive multiagent chemotherapy regimens for induction and consolidation phases with central nervous system prophylaxis and a maintenance phase lasting 12-18 months. We report on a case of long-term survival after one cycle of hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) and high-dose methotrexate. A 30-year-old woman diagnosed with T-LBL with a large mediastinal mass underwent one cycle of hyper-CVAD. Four days after the start of treatment, the mediastinal mass was markedly reduced. Treatment continued with one cycle of consolidation chemotherapy, comprising high-dose methotrexate and high-dose cytarabine. The patient then refused all further chemotherapeutic treatment. Seven years have passed without relapse. [ABSTRACT FROM AUTHOR]

The article discusses a study on the interaction of linker region of Ciona intestinalis voltage-sensitive phosphatase with lipid membrane. Topics covered include the effect of interdomain linker charge on the phosphatase activity and membrane interaction, the interaction between phosphoinositide binding motif (PBM) and membrane determined by quartz crystal microbalance (QCM) method and the membrane interaction of an enzyme.

A simple and cheap cholesterol biosensor was designed by immobilizing cholesterol oxidase (ChOx) and horseradish peroxidase (HRP) onto a poly(thionine)-modified glassy carbon electrode (GCE/PTH). Being mediated by hydroquinone (HQ), the immobilized HRP exhibited excellent electrocatalytic activity in reducing H2O2, which was produced from cholesterol by the enzymatic reaction of ChOx. The linear detection range for cholesterol was 25-125 µM, with a detection limit (S/N = 3) and a sensitivity of 6.3 µM and 0.18 µA/cm²/µM, respectively, under optimal conditions. The highly reproducible and sensitive GCE/PTH/ChOx/HRP sensor exhibited an interference-free signal for cholesterol detection with excellent recoveries for real sample analysis. [ABSTRACT FROM AUTHOR]

Sub-micrometer size gold particles were electrodeposited on a transparent fluorine-doped tin oxide (FTO) from acetonitrile solution containing AuCl4 and tetramethylammonium tetraflouroborate (TMATFB) for detecting NO2-. A series of two-electron (2e-) and one-electron (1e-) reductions of the AuCl4--AuCl2--Au redox systems were observed at FTO and a highly stable and homogeneous distribution of Au on FTO (Au/FTO) was obtained by stepping the potential from 0 to -0.55 V (vs. Ag/Ag+). The Au/FTO electrode exhibited sufficiently high catalytic activity toward the oxidation of NO2- with a detection limit (S/N = 3) and sensitivity of 2.95 µM and 223.4 µA⋅cm-2 ⋅mM-1, respectively, under optimal conditions. It exhibited an interference-free signal for NO2- detection with excellent recoveries from real samples. [ABSTRACT FROM AUTHOR]

Mycotic aneurysms are uncommon, but are fatal without appropriate management. Previous reports have shown that anaerobes and gram-negative organisms are less common but more dangerous than other causative agents of mycotic aneurysm. We report the case of a 60-year-old man with poorly controlled diabetes mellitus and atherosclerosis in the aorta, and a 10-day of history of lower abdominal pain and fever. This man was diagnosed with an uncommon abdominal aorta mycotic aneurysm caused by Bacteroides thetaiotaomicron and Acinetobacter lwoffii. The aneurysm was successfully treated with antibiotics therapy and aorto-bi-external iliac artery bypass with debridement of the infected aortic wall. We present this case together with a review of the relevant literature. [ABSTRACT FROM AUTHOR]

To ensure long-term stable dye-sensitized solar cells (DSCs) and modules, a hermetic sealing is required. This research investigates the chemical stability of I-/I3 - redox electrolyte and four different glass frits (GFs). Sintered GF layers were openly exposed to nonaqueous redox electrolyte and redox electrolyte with 1, 5, and 10wt% H2O in thin, encapsulated cells. The change in I3 - absorbance was assigned to a reaction between the GF and I-/I3 - electrolyte and was used to evaluate the chemical stability of the different GFs. The I3 - absorbance change was monitored over 100 days. Two out of the four GFs were unstable when H2O was added to the redox electrolyte. The H2O caused metal ion leaching which was determined from EDX analysis of the inorganic remains of electrolyte samples. A GF based on Bi2O3-SiO2-B2O3 with low bond strength leached bismuth into electrolyte and formed the BiI4 - complex. A ZnO-SiO2-Al2O3-based GF also became unstable when H2O was added to the redox electrolyte. Leaching of zinc ions due to exchange with H+ resulted in the formation of a zinc-iodine compound which caused I3 - depletion. By applying the test design to different types of GFs, the material suitability in the DSC working environment was investigated. [ABSTRACT FROM AUTHOR]

We report on the results from our deep Chandra observation (120 ks) of the supernova remnant (SNR) N49 and soft gamma-ray repeater (SGR) 0526-66 in the Large Magellanic Cloud. We firmly establish the detection of an ejecta "bullet" beyond the southwestern boundary of N49. The X-ray spectrum of the bullet is distinguished from that of the main SNR shell, showing significantly enhanced Si and S abundances. We also detect an ejecta feature in the eastern shell, which shows metal overabundances similar to those of the bullet. If N49 was produced by a core-collapse explosion of a massive star, the detected Si-rich ejecta may represent explosive O-burning or incomplete Si-burning products from deep interior of the SN. On the other hand, the observed Si/S abundance ratio in the ejecta may favor Type Ia origin for N49. We refine the Sedov age of N49, tSed ~ 4800 yr, with the explosion energy E0 ~ 1.8 x 1051 erg. Our blackbody (BB) + power law (PL) model for the quiescent X-ray emission from SGR 0526-66 indicates that the PL photon index (Γ ~ 2.5) is identical to that of PSR 1E1048.1-5937, the well-known candidate transition object between anomalous X-ray pulsars and SGRs. Alternatively, the two-component BB model implies X-ray emission from a small (R ~ 1 km) hot spot(s) (kT ~ 1 keV) in addition to emission from the neutron star's cooler surface (R ~ 10 km, kT ~ 0.4 keV). There is a considerable discrepancy in the estimated column toward 0526-66 between BB+PL and BB+BB model fits. Discriminating these spectral models would be crucial to test the long-debated physical association between N49 and 0526-66. [ABSTRACT FROM AUTHOR]

We fabricated well-aligned one-dimensional (1-D) titania nanotubes (TNT) on transparent conducting oxide (TCO) by anodization of Ti foil. Different lengths of TNTs were prepared by varying the applied potential (70V) time, and we investigated the performance of these TNTs in dye-sensitized solar cells (DSSCs), transplanted onto a 6 µm TNP adhesion layer. The fabricated TNTs arrays (length 15 µm) photoelectrode showed 24% increased efficiency compared to the TNP photoelectrode of 17 µm thickness. We further investigated the performances of DSSCs for the TNTs (1wt%) incorporated TNP photoelectrode and obtained 22% increased efficiency. The increased efficiency of the pure TNTs arrays and TNT-mixed TNP photoelectrodes was attributed to the directional electron movement of TNTs and light scattering effect of the TNT with the decreased rate of back electron transfer. The anodized and fabricated TNTs and DSSCs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), and electrochemical impedance spectroscopy (EIS). [ABSTRACT FROM AUTHOR]

Nanotechnology has opened new and exhilarating opportunities for exploring glucose biosensing applications of the newly prepared nanostructured materials. Nanostructured metal-oxides have been extensively explored to develop biosensors with high sensitivity, fast response times, and stability for the determination of glucose by electrochemical oxidation. This article concentrates mainly on the development of different nanostructured metal-oxide [such as ZnO, Cu(I)/(II) oxides, MnO2, TiO2, CeO2, SiO2, ZrO2, and other metal-oxides] based glucose biosensors. Additionally, we devote our attention to the operating principles (i.e., potentiometric, amperometric, impedimetric and conductometric) of these nanostructured metal-oxide based glucose sensors. Finally, this review concludes with a personal prospective and some challenges of these nanoscaled sensors. [ABSTRACT FROM AUTHOR]

Nanotechnology has opened new and exhilarating opportunities for exploring glucose biosensing applications of the newly prepared nanostructured materials. Nanostructured metal-oxides have been extensively explored to develop biosensors with high sensitivity, fast response times, and stability for the determination of glucose by electrochemical oxidation. This article concentrates mainly on the development of different nanostructured metal-oxide [such as ZnO, Cu(I)/(II) oxides, MnO2, TiO2, CeO2, SiO2, ZrO2, and other metal-oxides] based glucose biosensors. Additionally, we devote our attention to the operating principles (i.e., potentiometric, amperometric, impedimetric and conductometric) of these nanostructured metal-oxide based glucose sensors. Finally, this review concludes with a personal prospective and some challenges of these nanoscaled sensors. [ABSTRACT FROM AUTHOR]

Background Theoretically, the motion of a bipolar hip prosthesis is most likely to occur at the inner joint if the frictional coefficients are equal at both surfaces. However, many studies have suggested that mast motion occurs al the outer joint. Material and methods We performed an analysis of motion in a cadaveric bone model and in 50 patients during fluoroscopic examination, to determine how the motion is distributed between the two joints and what factors contribute to this distribution. Results The motion distributions varied widely between the patients. However, there was a relative preponderance (63-90%) of outer motion in all directions of leg movement in addition to a persistent coexistence of motion al both joints in 44 of 50 patients. This preponderance of outer motion was the result of an early impingement of the acetabular cup and structural differences between the two joints. Interpretation An adjustment of the positive eccentricity and a decrease in the frictional torque of the inner joint as a result of better lubrication and smoothness can be expected to improve the motion distribution, thus reducing the amount of acetabular erosion. [ABSTRACT FROM AUTHOR]

The cosmic origin of fluorine is still not well constrained. Several nucleosynthetic channels at different phases of stellar evolution have been suggested, but these must be constrained by observations. For this, the fluorine abundance trend with metallicity spanning a wide range is required. Our aim is to determine stellar abundances of fluorine for . We determine the abundances from HF lines in infrared K-band spectra () of cool giants, observed with the IGRINS and Phoenix high-resolution spectrographs. We derive accurate stellar parameters for all our observed K giants, which is important as the HF lines are very temperature-sensitive. We find that [F/Fe] is flat as a function of metallicity at [F/Fe]∼0, but increases as the metallicity increases. The fluorine slope shows a clear secondary behavior in this metallicity range. We also find that the [F/Ce] ratio is relatively flat for , and that for two metal-poor (), s-process element-enhanced giants, we do not detect an elevated fluorine abundance. We interpret all of these observational constraints as indications that several major processes are at play for the cosmic budget of fluorine over time: from those in massive stars at low metallicities, through the asymptotic giant branch star contribution at , to processes with increasing yields with metallicity at supersolar metallicities. The origins of the latter, and whether or not Wolf–Rayet stars and/or novae could contribute at supersolar metallicities, is currently not known. To quantify these observational results, theoretical modeling is required. More observations in the metal-poor region are required to clarify the processes there. [ABSTRACT FROM AUTHOR]

We present a blind comparison of two methods to measure the mean surface magnetic field strength of the classical T Tauri star CI Tau based on Zeeman broadening of sensitive spectral lines. Our approach takes advantage of the greater Zeeman broadening at near-infrared compared to optical wavelengths. We analyze a high signal-to-noise, high spectral resolution spectrum from 1.5 to 2.5 μm observed with IGRINS (Immersion GRating INfrared Spectrometer) on the Discovery Channel Telescope. Both stellar parameterization with MoogStokes (which assumes a uniform magnetic field) and modeling with SYNTHMAG (which includes a distribution of magnetic field strengths) yield consistent measurements for the mean magnetic field strength of CI Tau is B of ∼2.2 kG. This value is typical compared with measurements for other young T Tauri stars and provides an important contribution to the existing sample given that it is the only known developed planetary system hosted by a young classical T Tauri star. Moreover, we potentially identify an interesting and suggestive trend when plotting the effective temperature and the mean magnetic field strength of T Tauri stars. While a larger sample is needed for confirmation, this trend only appears for a subset of the sample, which may have implications regarding the magnetic field generation. [ABSTRACT FROM AUTHOR]

We present a long-exposure (∼10 hr), narrowband image of the supernova (SN) remnant Cassiopeia A (Cas A) centered at 1.644 μm emission. The passband contains [Fe ii] 1.644 μm and [Si i] 1.645 μm lines, and our “deep [Fe ii]+[Si i] image” provides an unprecedented panoramic view of Cas A, showing both shocked and unshocked SN ejecta, together with shocked circumstellar medium at subarcsecond (∼0.″7 or 0.012 pc) resolution. The diffuse emission from the unshocked SN ejecta has a form of clumps, filaments, and arcs, and their spatial distribution correlates well with that of the Spitzer [Si ii] infrared emission, suggesting that the emission is likely due to [Si i] not [Fe ii] as in shocked material. The structure of the optically invisible western area of Cas A is clearly seen for the first time. The area is filled with many quasi-stationary flocculi (QSFs) and fragments of the disrupted ejecta shell. We identified 309 knots in the deep [Fe ii]+[Si i] image and classified them into QSFs and fast-moving knots (FMKs). The comparison with previous optical plates indicates that the lifetime of most QSFs is ≳60 yr. The total H+He mass of QSFs is ≈0.23 M⊙, implying that the mass fraction of dense clumps in the progenitor’s mass ejection immediately prior to the SN explosion is about 4%–6%. FMKs in the deep [Fe ii]+[Si i] image mostly correspond to S-rich ejecta knots in optical studies, while those outside the southeastern disrupted ejecta shell appear Fe-rich. The mass of the [Fe ii] line emitting, shocked dense Fe ejecta is ∼3 × 10−5M⊙. [ABSTRACT FROM AUTHOR]

We investigate surface brightness profiles (SBPs) of dwarf galaxies in field, group, and cluster environments. With deep BVI images from the Korea Microlensing Telescope Network Supernova Program, SBPs of 38 dwarfs in the NGC 2784 group are fitted by a single-exponential or double-exponential model. We find that 53% of the dwarfs are fitted with single-exponential profiles (“Type I”), while 47% of the dwarfs show double-exponential profiles; 37% of all dwarfs have smaller sizes for the outer part than the inner part (“Type II”), while 10% have a larger outer than inner part (“Type III”). We compare these results with those in the field and in the Virgo cluster, where the SBP types of 102 field dwarfs are compiled from a previous study and the SBP types of 375 cluster dwarfs are measured using SDSS r-band images. As a result, the distributions of SBP types are different in the three environments. Common SBP types for the field, the NGC 2784 group, and the Virgo cluster are Type II, Type I and II, and Type I and III profiles, respectively. After comparing the sizes of dwarfs in different environments, we suggest that since the sizes of some dwarfs are changed due to environmental effects, SBP types are capable of being transformed and the distributions of SBP types in the three environments are different. We discuss possible environmental mechanisms for the transformation of SBP types. [ABSTRACT FROM AUTHOR]

We present a high-resolution, near-IR spectroscopic study of multiple outflows in the LkHα 234 star formation region using the Immersion GRating INfrared Spectrometer (IGRINS). Spectral mapping over the blueshifted emission of HH 167 allowed us to distinguish at least three separate, spatially overlapped outflows in H2 and [Fe ii] emission. We show that the H2 emission represents not a single jet but rather complex multiple outflows driven by three known embedded sources: MM1, VLA 2, and VLA 3. There is a redshifted H2 outflow at a low velocity, VLSR <+50 km s−1, with respect to the systemic velocity of VLSR = −11.5 km s−1, that coincides with the H2O masers seen in earlier radio observations 2″ southwest of VLA 2. We found that the previously detected [Fe ii] jet with 100 km s−1 driven by VLA 3B is also detected in H2 emission and confirm that this jet has a position angle of about 240°. Spectra of the redshifted knots at 14″–65″ northeast of LkHα 234 are presented for the first time. These spectra also provide clues to the existence of multiple outflows. We detected high-velocity (50–120 km s−1) H2 gas in the multiple outflows around LkHα 234. Since these gases move at speeds well over the dissociation velocity (>40 km s−1), the emission must originate from the jet itself rather than H2 gas in the ambient medium. Also, position–velocity and excitation diagrams indicate that emission from knot C in HH 167 comes from two different phenomena, shocks and photodissociation. [ABSTRACT FROM AUTHOR]

At 60 pc, TW Hydra (TW Hya) is the closest example of a star with a gas-rich protoplanetary disk, though TW Hya may be relatively old (3–15 Myr). As such, TW Hya is especially appealing for testing our understanding of the interplay between stellar and disk evolution. We present a high-resolution near-infrared spectrum of TW Hya obtained with the Immersion GRating INfrared Spectrometer (IGRINS) to re-evaluate the stellar parameters of TW Hya. We compare these data to synthetic spectra of magnetic stars produced by MoogStokes, and use sensitive spectral line profiles to probe the effective temperature, surface gravity, and magnetic field. A model with K, , and kG best fits the near-infrared spectrum of TW Hya. These results correspond to a spectral type of M0.5 and an age of 8 Myr, which is well past the median life of gaseous disks. [ABSTRACT FROM AUTHOR]

SS 433 is an X-ray binary and the source of sub-relativistic, precessing, baryonic jets. We present high-resolution spectrograms of SS 433 in the infrared H and K bands. The spectrum is dominated by hydrogen and helium emission lines. The precession phase of the emission lines from the jet continues to be described by a constant period, . The limit on any secularly changing period is . The He i line has complex and variable P-Cygni absorption features produced by an inhomogeneous wind with a maximum outflow velocity near 900 km s−1. The He ii emission lines in the spectrum also arise in this wind. The higher members of the hydrogen Brackett lines show a double-peaked profile with symmetric wings extending more than ±1500 km s−1 from the line center. The lines display radial velocity variations in phase with the radial velocity variation expected of the compact star, and they show a distortion during disk eclipse that we interpret as a rotational distortion. We fit the line profiles with a model in which the emission comes from the surface of a symmetric, Keplerian accretion disk around the compact object. The outer edge of the disk has velocities that vary from 110 to 190 km s−1. These comparatively low velocities place an important constraint on the mass of the compact star: its mass must be less than and is probably less than . [ABSTRACT FROM AUTHOR]

We report the results of broadband (0.95–2.46 μm) near-infrared spectroscopic observations of the Cassiopeia A supernova remnant. Using a clump-finding algorithm in two-dimensional dispersed images, we identify 63 “knots” from eight slit positions and derive their spectroscopic properties. All of the knots emit [Fe ii] lines together with other ionic forbidden lines of heavy elements, and some of them also emit H and He lines. We identify 46 emission line features in total from the 63 knots and measure their fluxes and radial velocities. The results of our analyses of the emission line features based on principal component analysis show that the knots can be classified into three groups: (1) He-rich, (2) S-rich, and (3) Fe-rich knots. The He-rich knots have relatively small, , line-of-sight speeds and radiate strong He i and [Fe ii] lines resembling closely optical quasi-stationary flocculi of circumstellar medium, while the S-rich knots show strong lines from O-burning material with large radial velocities up to indicating that they are supernova ejecta material known as fast-moving knots. The Fe-rich knots also have large radial velocities but show no lines from O-burning material. We discuss the origin of the Fe-rich knots and conclude that they are most likely “pure” Fe ejecta synthesized in the innermost region during the supernova explosion. The comparison of [Fe ii] images with other waveband images shows that these dense Fe ejecta are mainly distributed along the southwestern shell just outside the unshocked 44Ti in the interior, supporting the presence of unshocked Fe associated with 44Ti. [ABSTRACT FROM AUTHOR]

Ages and masses of young stars are often estimated by comparing their luminosities and effective temperatures to pre-main-sequence stellar evolution tracks, but magnetic fields and starspots complicate both the observations and evolution. To understand their influence, we study the heavily spotted weak-lined T-Tauri star LkCa 4 by searching for spectral signatures of radiation originating from the starspot or starspot groups. We introduce a new methodology for constraining both the starspot filling factor and the spot temperature by fitting two-temperature stellar atmosphere models constructed from Phoenix synthetic spectra to a high-resolution near-IR IGRINS spectrum. Clearly discernable spectral features arise from both a hot photospheric component ∼ 4100 K and a cool component ∼ 2700–3000 K, which covers ∼80% of the visible surface. This mix of hot and cool emission is supported by analyses of the spectral energy distribution, rotational modulation of colors and of TiO band strengths, and features in low-resolution optical/near-IR spectroscopy. Although the revised effective temperature and luminosity make LkCa 4 appear to be much younger and of much lower mass than previous estimates from unspotted stellar evolution models, appropriate estimates will require the production and adoption of spotted evolutionary models. Biases from starspots likely afflict most fully convective young stars and contribute to uncertainties in ages and age spreads of open clusters. In some spectral regions, starspots act as a featureless “veiling” continuum owing to high rotational broadening and heavy line blanketing in cool star spectra. Some evidence is also found for an anticorrelation between the velocities of the warm and cool components. [ABSTRACT FROM AUTHOR]

We report a study of the three-dimensional (3D) outflow structure of a 15″ × 13″ area around the H2 peak 1 in Orion KL with slit-scan observations (13 slits) using the Immersion Grating Infrared Spectrograph. The datacubes have a high-velocity resolution (∼7.5 km s−1), provide high-contrast imaging within ultra-narrow bands, and enable the detection of the main stream of the previously reported H2 outflow fingers. We identified 31 distinct fingers in the H2 1−0 S(1) λ2.122 μm emission. The line profile at each finger shows multiple-velocity peaks with a strong low-velocity component around the systemic velocity at = +8 km s−1 and high-velocity emission ( = 45–135 km s−1), indicating a typical bow-shock. The observed radial velocity gradients of ∼4 km s−1 arcsec−1 agree well with the velocities inferred from large-scale proper motions, where the projected motion is proportional to the distance from a common origin. We construct a conceptual 3D map of the fingers with estimated inclination angles of 57°–74°. The extinction difference (ΔAv > 10 mag) between blueshifted and redshifted fingers indicates high internal extinction. The extinction, the overall angular spread, and the scale of the flow argue for an ambient medium with a very high density (105–106 cm−3), consistent with molecular line observations of the Orion Molecular Cloud core. The radial velocity gradients and the 3D distributions of the fingers together support the hypothesis of a simultaneous radial explosion of the Orion KL outflow. [ABSTRACT FROM AUTHOR]

We have detected molecular and atomic line emission from the hot and warm disks of two Class I sources, IRAS 03445+3242 and IRAS 04239+2436, using the high-resolution Immersion GRating INfrared Spectrograph (IGRINS). CO overtone band transitions and near-IR lines of Na i and Ca i, all in emission, trace the hot inner disk, while CO rovibrational absorption spectra of the first overtone transition trace the warm gas within the inner few AU of the disk. The emission-line profiles for both sources show evidence for Keplerian disks. A thin Keplerian disk with power-law temperature and column density profiles with a projected rotational velocity of ∼60–75 km s−1 and a gas temperature of ∼3500 K at the innermost annulus can reproduce the CO overtone band emission. Na i and Ca i emission lines also arise from this disk, but they show complicated line features possibly affected by photospheric absorption lines. Multi-epoch observations show asymmetric variations of the line profiles on one-year (CO overtone bandhead and atomic lines for IRAS 03445+3242) or on one-day (atomic lines for IRAS 04239+2436) timescales, implying non-axisymmetric features in disks. The narrow CO rovibrational absorption spectra (v = 0 2) indicate that both warm (>150 K) and cold (∼20–30 K) CO gas are present along the line of sight to the inner disk. This study demonstrates the power of IGRINS as a tool for studies of the sub-AU-scale hot and AU-scale warm protoplanetary disks with its simultaneous coverage of the full H and K bands with high spectral resolution (R = 45,000) allowing many aspects of the sources to be investigated at once. [ABSTRACT FROM AUTHOR]

We present the results of high-resolution near-IR spectroscopy toward the multiple outflows around the Herbig Be star LkHα 234 using the Immersion Grating Infrared Spectrograph. Previous studies indicate that the region around LkHα 234 is complex, with several embedded young stellar objects and the outflows associated with them. In simultaneous H- and K-band spectra from HH 167, we detected 5 [Fe ii] and 14 H2 emission lines. We revealed a new [Fe ii] jet driven by radio continuum source VLA 3B. Position–velocity diagrams of the H2 1−0 S(1) λ2.122 μm line show multiple velocity peaks. The kinematics may be explained by a geometrical bow shock model. We detected a component of H2 emission at the systemic velocity (VLSR = −10.2 km s−1) along the whole slit in all slit positions, which may arise from the ambient photodissociation region. Low-velocity gas dominates the molecular hydrogen emission from knots A and B in HH 167, which is close to the systemic velocity; [Fe ii] emission lines are detected farther from the systemic velocity, at VLSR = −100–−130 km s−1. We infer that the H2 emission arises from shocked gas entrained by a high-velocity outflow. Population diagrams of H2 lines imply that the gas is thermalized at a temperature of 2500–3000 K and the emission results from shock excitation. [ABSTRACT FROM AUTHOR]

We present the results of extinction measurements toward the main ejecta shell of the Cassiopeia A supernova (SN) remnant using the flux ratios between the two near-infrared (NIR) [Fe ii] lines at 1.26 and 1.64 μm. We find a clear correlation between the NIR extinction () and the radial velocity of ejecta knots, showing that redshifted knots are systematically more obscured than blueshifted ones. This internal “self-extinction” strongly indicates that a large amount of SN dust resides inside and around the main ejecta shell. At one location in the southern part of the shell, we measure by the SN dust of 0.23 ± 0.05 mag. By analyzing the spectral energy distribution of thermal dust emission at that location, we show that there are warm (∼100 K) and cool (∼40 K) SN dust components and that the latter is responsible for the observed . We investigate the possible grain species and size of each component and find that the warm SN dust needs to be silicate grains such as MgSiO3, Mg2SiO4, and SiO2, whereas the cool dust could be either small (≲0.01 μm) Fe or large (≳0.1 μm) Si grains. We suggest that the warm and cool dust components in Cassiopeia A represent grain species produced in diffuse SN ejecta and in dense ejecta clumps, respectively. [ABSTRACT FROM AUTHOR]