THE ORIGIN OF THE X-RAY EMISSION FROM THE HIGH-VELOCITY CLOUD MS30.7-81.4-118

Henley, David B.,Shelton, Robin L.,Kwak, Kyujin IOP Publishing 2014 The Astrophysical journal Vol.791 No.1

<P>A soft X-ray enhancement has recently been reported toward the high-velocity cloud MS30.7-81.4-118 (MS30.7), a constituent of the Magellanic Stream. In order to investigate the origin of this enhancement, we have analyzed two overlapping XMM-Newton observations of this cloud. We find that the X-ray enhancement is similar to 6 or similar to 100 pc across, and is concentrated to the north and west of the densest part of the cloud. We modeled the X-ray enhancement with a variety of spectral models. A single-temperature equilibrium plasma model yields a temperature of (3.69(-0.44)(+0.47)) x 10(6) K and a 0.4-2.0 keV luminosity of 7.9 x 10(33) erg s(-1). However, this model underpredicts the on-enhancement emission around 1 keV, which may indicate the additional presence of hotter plasma (T 107 K), or that recombination emission is important. We examined several different physical models for the origin of the X-ray enhancement. We find that turbulent mixing of cold cloud material with hot ambient material, compression or shock heating of a hot ambient medium, and charge exchange reactions between cloud atoms and ions in a hot ambient medium all lead to emission that is too faint. In addition, shock heating in a cool or warm medium leads to emission that is too soft (for reasonable cloud speeds). We find that magnetic reconnection could plausibly power the observed X-ray emission, but resistive magnetohydrodynamical simulations are needed to test this hypothesis. If magnetic reconnection is responsible for the X-ray enhancement, the observed spectral properties could potentially constrain the magnetic field in the vicinity of the Magellanic Stream.</P>

Southeast Asian Studies and the Reality of Southeast Asia

Henley, David Korea Institute for ASEAN Studies 2020 Suvannabhumi Vol.12 No.2

Southeast Asianists have a perennial tendency to question the reality of the region in which they are specialized. Yet while scholars have doubted, Southeast Asians at large have become increasingly sure that Southeast Asia does exist, and increasingly inclined to identify with it. This article summarizes a range of evidence to that effect, from opinion poll research and from the history of ASEAN and other pan-Southeast Asian institutions, and uses it to construct a critique of the relativistic view that Southeast Asia is a fluid and ill-defined concept. Southeast Asians today tend to see Southeast Asia as a cultural as well as a geographical and institutional unit. The nature of the perceived cultural unity remains unclear, and further research is called for in this area. There are reasons to think, however, that it reflects real inheritances from a shared past, as well as shared aspirations for the future.

SIMULATIONS OF HIGH-VELOCITY CLOUDS. II. ABLATION FROM HIGH-VELOCITY CLOUDS AS A SOURCE OF LOW-VELOCITY HIGH IONS

Henley, David B.,Kwak, Kyujin,Shelton, Robin L. IOP Publishing 2012 The Astrophysical journal Vol.753 No.1

<P>In order to determine if the material ablated from high-velocity clouds (HVCs) is a significant source of low-velocity high ions (C IV, NV, and OVI) such as those found in the Galactic halo, we simulate the hydrodynamics of the gas and the time-dependent ionization evolution of its carbon, nitrogen, and oxygen ions. Our suite of simulations examines the ablation of warm material from clouds of various sizes, densities, and velocities as they pass through the hot Galactic halo. The ablated material mixes with the environmental gas, producing an intermediate-temperature mixture that is rich in high ions and that slows to the speed of the surrounding gas. We find that the slow mixed material is a significant source of the low-velocity OVI that is observed in the halo, as it can account for at least similar to 1/3 of the observed OVI column density. Hence, any complete model of the high ions in the halo should include the contribution to the OVI from ablated HVC material. However, such material is unlikely to be a major source of the observed CIV, presumably because the observed C IV is affected by photoionization, which our models do not include. We discuss a composite model that includes contributions from HVCs, supernova remnants, a cooling Galactic fountain, and photoionization by an external radiation field. By design, this model matches the observed OVI column density. This model can also account for most or all of the observed C IV, but only half of the observed NV.</P>

Southeast Asian Studies and the Reality of Southeast Asia

( David Henley ) 부산외국어대학교 아세안연구원(구 부산외국어대학교 동남아지역원) 2020 Suvannabhumi Vol.12 No.2

Southeast Asianists have a perennial tendency to question the reality of the region in which they are specialized. Yet while scholars have doubted, Southeast Asians at large have become increasingly sure that Southeast Asia does exist, and increasingly inclined to identify with it. This article summarizes a range of evidence to that effect, from opinion poll research and from the history of ASEAN and other pan-Southeast Asian institutions, and uses it to construct a critique of the relativistic view that Southeast Asia is a fluid and ill-defined concept. Southeast Asians today tend to see Southeast Asia as a cultural as well as a geographical and institutional unit. The nature of the perceived cultural unity remains unclear, and further research is called for in this area. There are reasons to think, however, that it reflects real inheritances from a shared past, as well as shared aspirations for the future.

자녀들에게 하나님을 생생하게 전달하라 : 아동 교육 전문가 캐린 헨리와의 대담

캐린 헨리 두란노 2005 목회와 신학 Vol.- No.192

Nutritional Aspects of Isolated Soy Protein

M.W. Sei,E.C. Henley 한국식품과학회 1993 식품과학과 산업 Vol.26 No.2

MODELING THE X-RAYS RESULTING FROM HIGH-VELOCITY CLOUDS

Shelton, R. L.,Kwak, K.,Henley, D. B. IOP Publishing 2012 The Astrophysical journal Vol.751 No.2

<P>With the goal of understanding why X-rays have been reported near some high-velocity clouds, we perform detailed three-dimensional hydrodynamic and magnetohydrodynamic simulations of clouds interacting with environmental gas like that in the Galaxy's thick disk/halo or the Magellanic Stream. We examine two scenarios. In the first, clouds travel fast enough to shock heat warm environmental gas. In this scenario, the X-ray productivity depends strongly on the speed of the cloud and the radiative cooling rate. In order to shock heat environmental gas to temperatures of >= 10(6) K, cloud speeds of >= 300 km s(-1) are required. If cooling is quenched, then the shock-heated ambient gas is X-ray emissive, producing bright X-rays in the 1/4 keV band and some X-rays in the 3/4 keV band due to O VII and other ions. If, in contrast, the radiative cooling rate is similar to that of collisional ionizational equilibrium plasma with solar abundances, then the shocked gas is only mildly bright and for only about 1 Myr. The predicted count rates for the non-radiative case are bright enough to explain the count rate observed with XMM-Newton toward a Magellanic Stream cloud and some enhancement in the ROSAT 1/4 keV count rate toward Complex C, while the predicted count rates for the fully radiative case are not. In the second scenario, the clouds travel through and mix with hot ambient gas. The mixed zone can contain hot gas, but the hot portion of the mixed gas is not as bright as those from the shock-heating scenario.</P>

Nutritional Aspects of Isolated Soy Protein

M. W. Sei,E. C. Henley 한국콩연구회 1993 한국콩연구회소식 Vol.78 No.-

Metabotropic Glutamate Receptor-Mediated LTD Involves Two Interacting Ca²⁺ Sensors, NCS-1 and PICK1

Jo, Jihoon,Heon, Seok,Kim, Myung Jong,Son, Gi Hoon,Park, Yunkyung,Henley, Jeremy M.,Weiss, Jamie L.,Sheng, Morgan,Collingridge, Graham L.,Cho, Kwangwook Elsevier 2008 Neuron Vol.60 No.6

<P><B>Summary</B></P><P>There are two major forms of long-term depression (LTD) of synaptic transmission in the central nervous system that require activation of either N-methyl-D-aspartate receptors (NMDARs) or metabotropic glutamate receptors (mGluRs). In synapses in the perirhinal cortex, we have directly compared the Ca<SUP>2+</SUP> signaling mechanisms involved in NMDAR-LTD and mGluR-LTD. While both forms of LTD involve Ca<SUP>2+</SUP> release from intracellular stores, the Ca<SUP>2+</SUP> sensors involved are different; NMDAR-LTD involves calmodulin, while mGluR-LTD involves the neuronal Ca<SUP>2+</SUP> sensor (NCS) protein NCS-1. In addition, there is a specific requirement for IP3 and PKC, as well as protein interacting with C kinase (PICK-1) in mGluR-LTD. NCS-1 binds directly to PICK1 via its BAR domain in a Ca<SUP>2+</SUP>-dependent manner. Furthermore, the NCS-1-PICK1 association is stimulated by activation of mGluRs, but not NMDARs, and introduction of a PICK1 BAR domain fusion protein specifically blocks mGluR-LTD. Thus, NCS-1 plays a distinct role in mGluR-LTD.</P>

Utility of Seated Lateral Radiographs in the Diagnosis and Classification of Lumbar Degenerative Spondylolisthesis

Issa Tariq Z.,Lee Yunsoo,Berthiaume Emily,Lambrechts Mark J.,Zaworski Caroline,Qadiri Qudratallah S.,Spracklen Henley,Padovano Richard,Weber Jackson,Mangan John J.,Canseco Jose A.,Woods Barrett I.,Kay 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.4

Study Design: Retrospective cohort study.Purpose: Our goal was to determine which radiographic images are most essential for degenerative spondylolisthesis (DS) classification and instability detection.Overview of Literature: The heterogeneity in DS requires multiple imaging views to evaluate vertebral translation, disc space, slip angle, and instability. However, there are several restrictions on frequently used imaging perspectives such as flexion-extension and upright radiography.Methods: We assessed baseline neutral upright, standing flexion, seated lateral radiographs, and magnetic resonance imaging (MRI) for patients identified with spondylolisthesis from January 2021 to May 2022 by a single spine surgeon. DS was classified by Meyerding and Clinical and Radiographic Degenerative Spondylolisthesis classifications. A difference of >10° or >8% between views, respectively, was used to characterize angular and translational instability. Analysis of variance and paired chi-square tests were utilized to compare modalities.Results: A total of 136 patients were included. Seated lateral and standing flexion radiographs showed the greatest slip percentage (16.0% and 16.7%), while MRI revealed the lowest (12.2%, <i>p</i> <0.001). Standing flexion and lateral radiographs when seated produced more kyphosis (4.66° and 4.97°, respectively) than neutral upright and MRI (7.19° and 7.20°, <i>p</i> <0.001). Seated lateral performed similarly to standing flexion in detecting all measurement parameters and categorizing DS (all <i>p</i> >0.05). Translational instability was shown to be more prevalent when associated with seated lateral or standing flexion than when combined with neutral upright (31.5% vs. 20.2%, <i>p</i> =0.041; and 28.1% vs. 14.6%, <i>p</i> =0.014, respectively). There were no differences between seated lateral or standing flexion in the detection of instability (all <i>p</i> >0.20).Conclusions: Seated lateral radiographs are appropriate alternatives for standing flexion radiographs. Films taken when standing up straight do not offer any more information for DS detection. Rather than standing flexion-extension radiographs, instability can be detected using an MRI, which is often performed preoperatively, paired with a single seated lateral radiograph.