bluuebunny/crossref_metadata_2025 huggingface dataset:
THE THEORY OF PULSAR WIND NEBULAE
Authors: AMATO ELENA
Published: March 2014

I will review the current status of our theoretical understanding of Pulsar Winds and associated nebulae (PWNe). In recent years, axisymmetric models of pulsar winds with a latitude dependent energy flux have proved very successful at explaining the morphology of PWNe as seen in the X-rays. This success has prompted developments aimed at using multi-wavelength observations of these nebulae as a diagnostics of the hidden physics of the pulsar wind and of the mechanism(s) through which particles are accelerated in these sources.

I will discuss these most recent developments in terms of the information that we infer from detailed comparison of simulated non-thermal emission with current observations.
THE H.E.S.S. EXTRAGALACTIC SKY
Authors:   (for the H.E.S.S. Collaboration), LENAIN JEAN-PHILIPPE
Published: March 2014

More than fifty extragalactic very high energy (VHE; E > 100 GeV) sources have been found using ground-based imaging atmospheric Cherenkov telescopes, about twenty of which have been discovered using the H.E.S.S. (High Energy Stereoscopic System) experiment based in Namibia. Even though BL Lac objects are the dominant class of VHE detected extragalactic objects, other types of sources (starburst galaxies, radio galaxies or flat spectrum radio quasars) begin to emerge. A review of the extragalactic sources studied with H.E.S.S. is given, with an emphasis on new results.
JET PROPAGATION AND DECELERATION
Authors: PERUCHO MANEL
Published: March 2014

Extragalactic jets in active galactic nuclei (AGN) are divided into two morphological types, namely Fanaroff-Riley I (FRI) and Fanaroff-Riley II (FRII). The former show decollimated structure at the kiloparsec scales and are thought to be decelerated by entrainment within the first kiloparsecs of evolution inside the host galaxy. The entrainment and deceleration can be, at least partly, due to the interaction of jets with stellar winds and gas clouds that enter in the jet as they orbit around the galactic centre. In this contribution, I review recent simulations to study the dynamic effect of entrainment from stellar winds in jets and the direct interaction of jets with gas clouds and stellar winds. I also briefly describe the importance of these interactions as a possible scenario of high-energy emission from extragalactic jets.
THE PUZZLING JET AND PULSAR WIND NEBULA OF IGR J11014-6103
Authors: PAVAN LUCIA , BORDAS POL , PÜHLHOFER GERD , FILIPOVIC MIROSLAV D. , DE HORTA AIN , O' BRIEN ANDREW , CRAWFORD EVAN , BALBO MATTEO , WALTER ROLAND , BOZZO ENRICO , FERRIGNO CARLO , STELLA LUIGI
Published: March 2014

IGR J11014-6103 is a hard X-ray source discovered by INTEGRAL. Follow-up X-ray and radio observations revealed an elongated pulsar wind nebula formed by a neutron star escaping supersonically its parent supernova remnant SNR MSH 11-61A. The pulsar also emits highly collimated jets extending perpendicularly to the direction of motion. The jet has a continuous helical structure extending up to more than 10 parsecs. IGR J11014-6103 is a laboratory to study jet ejection in the wind of a pulsar and to constrain the core collapse supernova mechanism responsible for the observed pulsar kick velocity in excess of 1000 km/s.
JITTER POLARIZATION FOR GRB PROMPT EMISSION
Authors: MAO JIRONG
Published: March 2014

The radiation of relativistic electrons in random and small-scale magnetic field is called jitter radiation. We apply jitter process to study the polarization feature of GRB prompt emission. A two-dimensional compressed slab which contains stochastic magnetic field is applied in our model. If jitter condition is satisfied, the high degree polarization can be achieved when the angle between line-of-sight and slab plane is small. Moreover, micro-emitters with mini-jet structure and jet off-axis effect are considered.
VERITAS OBSERVATIONS OF RELATIVISTIC OUTFLOWS IN LOW- AND INTERMEDIATE-FREQUENCY-PEAKED BL LAC OBJECTS
Authors:   (for the VERITAS Collaboration), PROKOPH HEIKE
Published: March 2014

The majority of blazars detected at very high energies (VHE; E > 100 GeV) are high-frequency-peaked BL Lac objects (HBLs). Low- and intermediate-frequency-peaked BL Lacs (LBLs/IBLs with synchrotron-peak frequencies in the infrared and optical regime) are generally more powerful, more luminous, and have a richer jet environment than HBLs. However, only a handful of these IBL and LBLs have been detected by ground-based gamma-ray telescopes, typically during high-flux states. The VERITAS array has been monitoring five known VHE LBLs/IBLs since 2009: 3C 66A, W Comae, PKS 1424+240, S5 0716+714 and BL Lacertae, with typical exposures of 5-10 hours per year. The results of these long-term observations are presented, including a bright, subhour-scale VHE flare of BL Lacertae in June 2011, the first low-state detections of 3C 66A and W Comae, and the detection and characterization of the IBL B2 1215+30.
TIME-DEPENDENT SSC COOLING EFFECTS ON BLAZAR EMISSION
Authors: ZACHARIAS MICHAEL , SCHLICKEISER REINHARD
Published: March 2014

Blazars are among the most violent sources in the cosmos exhibiting flaring states with remarkably different variability time scales. Especially rapid flares with flux doubling time scales of the order of minutes have been puzzling for quite some time. Many modeling attempts use the well known linear and steady-state scenario for the cooling and emission processes in the jet, albeit the obvious strongly time-dependent nature of flares. Due to the feedback of the self-produced synchrotron radiation with additional scattering by the relativistic electrons, the synchrotron-self Compton (SSC) effect is inherently time-dependent. Recently, an analytical analysis on the effects of this nonlinear behavior has been presented. Here, we summarize these results concerning the effect of the time-dependent SSC cooling on the spectral energy distribution (SED), and the synchrotron lightcurves of blazars. For that, we calculated analytically the synchrotron, SSC and external Compton (EC) component of the SED, giving remarkably different spectral features compared to the standard linear approach. The resulting fluxes strongly depend on the parameters, and SSC might have a strong effect even in sources with strong external photon fields (such as FSRQs). For the synchrotron lightcurve we considered the effects of retardation, including the geometry of the source. The retardation might smear out some effects of the time-dependent cooling, but since lightcurves and SEDs have to be fitted simultaneously with the same set of parameters, the results give nonetheless important clues about the source. Thus, we argue for a wide utilization of the time-dependent treatment in modeling (especially rapid) blazar flares, since it accounts for features in the SED and the lightcurves that are usually accounted for by introducing several breaks in the electron distribution without any physical justification.
GAMMA-RAY ASTRONOMY WITH THE HAWC OBSERVATORY
Authors:   (for the HAWC Collaboration), LAUER ROBERT J.
Published: March 2014

The High Altitude Water Cherenkov (HAWC) Observatory is a wide field-of-view gamma-ray detector, sensitive to primary energies between 50 GeV and 100 TeV. The array is being built at an altitude of 4,100 m on the Sierra Negra volcano in Puebla, Mexico. With a duty cycle close to 100% and a daily coverage of ~ 8 sr of the sky above it, HAWC is ideally suited to detect bright transient events at TeV energies such as gamma-ray bursts or flares from active galactic nuclei. The array will provide an unbiased survey of gamma-ray sources at energies above 100 GeV and probe the origins of astrophysical photon emission at the highest energies. The modular design of HAWC made it possible to start data taking in September 2012 with a partial array. Operation continues while the number of water Cherenkov detectors is growing, which allowed a smooth transition to full scientific operation with 111 detectors in August 2013. The completion of the full array with 300 detectors is planned for the summer of 2014. In these proceedings, we will give an overview of the status and performance of the HAWC observatory and discuss observation strategies for various gamma-ray phenomena.
PARTICLE ACCELERATION AND MAGNETIC FIELD GENERATION IN SHEAR-FLOWS
Authors: NISHIKAWA K.-I. , HARDEE P. , MIZUNO Y. , DUŢAN I. , ZHANG B. , MEDVEDEV M. , MELI A. , CHOI E. J. , MIN K. W. , NIEMIEC J. , NORDLUND Å , FREDERIKSEN J. , SOL H. , POHL M. , HARTMANN D. H. , MARSCHER A. , GÓMEZ J. L.
Published: March 2014

We have investigated the generation of magnetic fields associated with velocity shear between an unmagnetized relativistic (core) jet and an unmagnetized sheath plasma by the kinetic Kelvin-Helmholtz instability for different mass ratios (m i /m e = 1, 20, and 1836) and different jet Lorentz factors. We found that electron-positron cases have alternating magnetic fields instead of the DC magnetic fields found in electron-ion cases. We have also investigated particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma for electron-positron and electron-ion plasmas. Strong magnetic fields generated in the trailing shock lead to transverse deflection and acceleration of the electrons. We have self-consistently calculated the radiation from the electrons accelerated in the turbulent magnetic fields for different jet Lorentz factors. We find that the synthetic spectra depend on the bulk Lorentz factor of the jet, the jet temperature, and the strength of the magnetic fields generated in the shock.
CURRENT DRIVEN KINK INSTABILITY IN A MAGNETICALLY DOMINATED ROTATING RELATIVISTIC JET
Authors: MIZUNO YOSUKE , NISHIKAWA KEN-ICHI , LYUBARSKY YURI , HARDEE PHILIP E.
Published: March 2014

We have investigated the influence of jet rotation and differential motion on the linear and nonlinear development of the current-driven (CD) kink instability of force-free helical magnetic equilibria via three-dimensional relativistic magnetohydrodynamic simulations. In this study, we follow the temporal development within a periodic computational box. Displacement of the initial helical magnetic field leads to the growth of the CD kink instability. In the rotating relativistic jet case, developing helical kink structure propagates along jet as it grows in amplitude. The growth rate of the CD kink instability does not depend on the jet rotation. The coupling of multiple unstable wavelengths is crucial to determining whether the jet is eventually disrupted in the nonlinear stage. The CD kink instability deformed magnetic field may trigger magnetic reconnection in the jet.
THE DYNAMICS OF SLIM DISKS WITH LARGE-SCALE MAGNETIC FIELDS
Authors: MA RENYI
Published: March 2014

As suggested by recent observations, we explore the influences of large-scale magnetic fields on the dynamics of slim disks. The magnetic fields are assumed to be self-similar and be a fixed fraction of the total pressure at the footpoint. The global solutions show that the radial velocity increases and the disk temperature decreases with enhancing magnetic fields. The ratio of the jet kinetic power to disk luminosity is less than 0.1, which indirectly support the argument that radio-loud (RL) narrow-line Seyfert 1 galaxies (NLS1s) are similar to blazars, with jets pointing to us.
Stratigraphic correlation of Holocene phonolitic explosive episodes of the Teide–Pico Viejo Volcanic Complex, Tenerife
Authors: García Olaya , Guzmán Silvina , Martí Joan
Published: March 2014

Teide and Pico Viejo (TPV) are twin stratovolcanoes that form one of the largest alkaline volcanic complexes in the world. They began forming inside the caldera of Las Cañadas about 200 ka ago and are largely made up of an accumulation of mafic, intermediate and more recent felsic products that form lava flows. However, a significant number of Holocene pyroclastic deposits are also present. To quantify the explosive contribution to the construction of TPV, we re-examined its stratigraphy and identified several Holocene phonolitic explosive episodes ranging from Strombolian to sub-Plinian styles that are represented by fallout and pyroclastic density current deposits. Although some of the pumice deposits have been related to known sources, a few have not been linked to a specific vent. The use of field data as well as geochemical and mineralogical analysis helped to provide reliable criteria for robust correlations and to establish the relative stratigraphy of the deposits. The presence of these pyroclastic deposits in the recent history of the TPV complex suggests that these stratovolcanoes are entering a more explosive stage that represents a non-avoidable hazard for the island of Tenerife.
On Nash Equilibria for a Network Creation Game
Authors: Albers Susanne , Eilts Stefan , Even-Dar Eyal , Mansour Yishay , Roditty Liam
Published: March 2014

We study a basic network creation game proposed by Fabrikant et al. [2003]. In this game, each player (vertex) can create links (edges) to other players at a cost of
α
per edge. The goal of every player is to minimize the sum consisting of (a) the cost of the links he has created and (b) the sum of the distances to all other players.

Fabrikant et al. conjectured that there exists a constant
A
such that, for any
α
>
A
, all nontransient Nash equilibria graphs are trees. They showed that if a Nash equilibrium is a tree, the price of anarchy is constant. In this article, we disprove the tree conjecture. More precisely, we show that for any positive integer
n
0
, there exists a graph built by
n
≥
n
0
players which contains cycles and forms a nontransient Nash equilibrium, for any
α
with 1 <
α
≤ √
n
/2. Our construction makes use of some interesting results on finite affine planes. On the other hand, we show that, for
α
≥ 12
n
⌈log
n
⌉, every Nash equilibrium forms a tree.

Without relying on the tree conjecture, Fabrikant et al. proved an upper bound on the price of anarchy of
O
(√
α
), where
α
∈ [2,
n
2
. We improve this bound. Specifically, we derive a constant upper bound for
α
∈
O
(√
n
) and for
α
≥ 12
n
⌈log
n
⌉. For the intermediate values, we derive an improved bound of
O
(1 + (min{
α
2
/
n
,
n
2
/
α
})
1/3
). Additionally, we develop characterizations of Nash equilibria and extend our results to a weighted network creation game as well as to scenarios with cost sharing.
What Was, What Is, and What May Be in OP/OB
Authors: Porter Lyman W. , Schneider Benjamin
Published: March 2014

This article presents a personalized view of the history, development, and current shape of the related fields of industrial–organizational (I/O) psychology and organizational behavior (OB) by two authors who have personally experienced many of the events and changes that have occurred in these fields over the past 50 or so years. Particular attention is given to the interconnections and differences between I/O psychology and OB and to the implications of those differences and overlaps for research and professional practice. The article concludes with some thoughts about areas of potential advances that could be made in the future and a discussion of some of the challenges to be faced in making those kinds of progress.
Work–Family Boundary Dynamics
Authors: Allen Tammy D. , Cho Eunae , Meier Laurenz L.
Published: March 2014

Theory, constructs, and research with regard to individual work–family boundary management dynamics are reviewed with the goal of promoting a greater understanding and integration of the existing literature. The article begins by noting trends that have contributed to interest in the topic, and then outlines major theoretical perspectives on boundary management and boundary characteristics, integration/segmentation, and associated constructs. It next notes limitations of existing research and concludes with recommendations for future research.
Functional roles of capsaicin-sensitive intrinsic neural circuit in the regulation of esophageal peristalsis in rats: in vivo studies using a novel method
Authors: Shima Takeshi , Shiina Takahiko , Naitou Kiyotada , Nakamori Hiroyuki , Shimizu Yasutake
Published: March 2014

A well-developed myenteric plexus exists in the esophagus composed of striated muscle layers, but its functional role in controlling peristaltic movements remains to be clarified. The purpose of this study was to clarify the role of a local neural reflex consisting of capsaicin-sensitive primary afferent neurons and intrinsic neurons in esophageal peristalsis. We firstly devised a method to measure peristaltic movement of esophagus in vivo in rats. Rats were anesthetized with urethane, and esophageal intraluminal pressure and propelled intraluminal liquid volume were recorded. In the experimental system, an intraluminal pressure stimulus evoked periodic changes in intraluminal pressure of the esophagus, which were consistently accompanied by intraluminal liquid propulsion. Bilateral vagotomy abolished changes in intraluminal pressure as well as liquid propulsion. These results indicate that the novel method is appropriate for inducing peristalsis in the esophagus composed of striated muscles. Then, by using the method, we examined functional roles of the local reflex in esophageal peristalsis. For that purpose, we used rats in which capsaicin-sensitive neurons had been destroyed. The esophagus of capsaicin-treated rats showed a multiphasic rise in intraluminal pressure, which may due to noncoordinated contractions of esophageal muscles, whereas a monophasic response was observed in the intact rat esophagus. In addition, destruction of capsaicin-sensitive neurons increased the propelled liquid volume and lowered the pressure threshold for initiating peristalsis. These results suggest that the local neural reflex consisting of capsaicin-sensitive neurons and intrinsic neurons contributes to coordination of peristalsis and suppresses mechanosensory function of vagal afferents in the esophagus.
Alkaline sphingomyelinase (NPP7) promotes cholesterol absorption by affecting sphingomyelin levels in the gut: A study with NPP7 knockout mice
Authors: Zhang Ping , Chen Ying , Cheng Yajun , Hertervig Erik , Ohlsson Lena , Nilsson Åke , Duan Rui-Dong
Published: March 2014

We previously showed that dietary sphingomyelin (SM) inhibited cholesterol absorption in animals. The key enzyme hydrolyzing SM in the gut is alkaline sphingomyelinase (alk-SMase, nucleotide pyrophosphatase/phosphodiesterase 7). Here using the fecal dual-isotope ratio method we compared cholesterol absorption in the wild-type (WT) and alk-SMase knockout (KO) mice. The animals were fed an emulsion containing [14C]cholesterol and [3H]sitosterol. The radioactivities in the lipids of the fecal samples collected 4, 8, and 24 h thereafter were determined, and the ratio of14C/3H was calculated. We found that the fecal [14C]cholesterol recovery in the KO mice was significantly higher than in the WT mice. A maximal 92% increase occurred 8 h after feeding. Recovery of [3H]sitosterol did not differ between the two groups. Accordingly, the14C-to-3H ratio of fecal lipids was 133% higher at 8 h and 75% higher at 24 h in the KO than in the WT mice. Decreased [14C]cholesterol was also found in the serum of the KO mice 4 h after feeding. Supplement of SM in the emulsion reduced the differences in fecal [14C]cholesterol recovery between the WT and KO mice because of a greater increase of [14C]cholesterol recovery in the WT mice. Without treatment, the KO mice had significantly higher SM levels in the intestinal content and feces, but not in the intestinal mucosa or serum. The expression of Niemann-Pick C1 like 1 protein in the small intestine was not changed. In conclusion, alk-SMase is a physiological factor promoting cholesterol absorption by reducing SM levels in the intestinal lumen.
High-density surface electromyography improves the identification of oscillatory synaptic inputs to motoneurons
Authors: Steeg Chiel van de , Daffertshofer Andreas , Stegeman Dick F. , Boonstra Tjeerd W.
Published: March 2014

Many studies have addressed corticomuscular coherence (CMC), but broad applications are limited by low coherence values and the variability across subjects and recordings. Here, we investigated how the use of high-density surface electromyography (HDsEMG) can improve the detection of CMC. Sixteen healthy subjects performed isometric contractions at six low-force levels using a pinch-grip, while HDsEMG of the adductor pollicis transversus and flexor and abductor pollicis brevis and whole-head magnetoencephalography were recorded. Different configurations were constructed from the HDsEMG grid, such as a bipolar and Laplacian montage, as well as a montage based on principal component analysis (PCA). CMC was estimated for each configuration, and the strength of coherence was compared across configurations. As expected, performance of the precision-grip task resulted in significant CMC in the β-frequency band (16–26 Hz). Compared with a bipolar EMG montage, all multichannel configurations obtained from the HDsEMG grid revealed a significant increase in CMC. The configuration, based on PCA, showed the largest (37%) increase. HDsEMG did not reduce the between-subject variability; rather, many configurations showed an increased coefficient of variation. Increased CMC presumably reflects the ability of HDsEMG to counteract inherent EMG signal factors—such as amplitude cancellation—which impact the detection of oscillatory inputs. In contrast, the between-subject variability of CMC most likely has a cortical origin.
HD Chromoendoscopy Coupled with DNA Mass Spectrometry Profiling Identifies Somatic Mutations in Microdissected Human Proximal Aberrant Crypt Foci
Authors: Drew David A. , Devers Thomas J. , O'Brien Michael J. , Horelik Nicole A. , Levine Joel , Rosenberg Daniel W.
Published: March 2014

Despite increased implementation of screening colonoscopy, interval cancers in the proximal colon remain a major public health concern. This fact underscores the limitations of current screening paradigms and the need for developing advanced endoscopic techniques. The density of aberrant crypt foci (ACF), the earliest identifiable mucosal abnormality, may serve as a surrogate marker for colon cancer risk, but has rarely been studied in the proximal colon. To this end, high-definition (HD) chromoendoscopy was conducted to define the relevance of ACF in the proximal colon. In addition, due to limited ACF size, the development of a combinatorial approach was required to maximize data acquisition obtained from individual biopsy samples. Proximal and distal ACF samples were characterized for a total of 105 mutations across 22 known tumor suppressor and proto-oncogenes using high-throughput Sequenom MassARRAY analysis. From this profiling, a discrete number of somatic mutations were identified, including APCR876* and FLT3I836M, as well as a deletion within the EGFR gene. Combined, these data highlight the significance of ACF within the context of colon cancer pathogenesis, particularly in the proximal colon.

Implications: The identification of cancer-related mutations in commonly overlooked mucosal lesions underscores the preventive benefit of implementing advanced endoscopic screening to larger patient populations, particularly in the proximal colon.

Visual Overview: http://mcr.aacrjournals.org/content/early/2014/05/22/1541-7786.MCR-13-0624/F1.large.jpg. Mol Cancer Res; 12(6); 823–9. ©2014 AACR.
Macular Lymphocytic Arteritis: Three Cases Questioning Its Classification as Primary Lymphocytic Vasculitis
Authors: Garcia Caroline , Dandurand Michel , Roger Pascal , Joujoux Jean-Marie , Meunier Laurent , Stoebner Pierre-Emmanuel
Published: March 2014

Background: Macular arteritis, macular lymphocytic arteritis (MLA) or lymphocytic thrombophilic arteritis all correspond to an identical new clinicopathological entity. Its individualization as a primary cutaneous lymphocytic arteritis is still controversial for certain authors as it could represent a latent form of cutaneous polyarteritis nodosa. Materials and Methods: We report here 3 additional cases of MLA, present a review of the literature and discuss the disease's nosology. Results: MLA is characterized clinically by a benign skin eruption consisting in bilateral asymptomatic erythematous/hyperpigmented macules mainly located on the lower legs and histologically by a medium-sized cutaneous lymphocytic prominent arteritis present in early cutaneous lesions. Conclusion: These findings support that MLA may be considered as a chronic and indolent primary lymphocytic cutaneous arteritis. Nevertheless, in some cases the objective obliteration of cutaneous vessels underlines the need for continuous monitoring in MLA patients.
Hemichorea Associated with Nonketotic Hyperglycemia: Clinical and Neuroimaging Features in 12 Patients
Authors: Guo Yan , Miao Yan-wei , Ji Xiao-fei , Li Ming , Liu Xuan , Sun Xiao-pei
Published: March 2014

Background: Nonketotic hyperglycemia is a rare cause of hemichorea. Patients with hemichorea associated with nonketotic hyperglycemia (HCNH) always have a favorable prognosis when given prompt treatment. Methods: We reviewed the medical records of 12 patients with HCNH in our hospital between January 2005 and January 2013. The clinical data, laboratory findings, and imaging features of the patients were collected. Results: All 12 patients were admitted to the hospital with a complaint of involuntary movements. Ten patients had a history of diabetes, while the other 2 patients had not been diagnosed. The mean level of blood glucose on admission was 330.7 ± 107.8 mg/dl, and the ketones were negative. A cranial computed tomography scan showed hyperdensity in the striatum, which quickly resolved. Magnetic resonance imaging showed hyperintensity on T1-weighted images without change over several months. Nearly all of the patients experienced relief from the hemichorea symptoms after correcting hyperglycemia with a combination of dopamine receptor inhibitors and the sedative lorazepam, if necessary. Conclusion: HCNH is a benign disorder, the pathogenesis of which remains unclear. Radiologic changes can provide guidance for early treatment and generally give an estimation of the degree of injury.
Retrospective Studies on Pediatric Infective Endocarditis over 40 Years in a Mid-West Area of China
Authors: Wang Wenshu , Sun Huichao , Lv Tiewei , Tian Jie
Published: March 2014

Objective: We have evaluated 106 pediatric cases of infective endocarditis (IE) to elucidate clinical manifestations and pathogenic microorganism profiling of IE in China. Methods: Clinical features, complications, pathogenic microorganisms, diagnosis and treatment of pediatric IE were reviewed in two groups of patients with IE from the different periods of time (group A, 34 cases obtained in the period from 2000 to 2011 and group B, 72 cases obtained in the period from 1964 to 1999). Results: A total of 106 pediatric patients with a definite diagnosis of IE based on the modified Duke criteria were enrolled and evaluated in this study. By comparing two groups of patients from different time periods, we found that the incidence of rheumatic heart disease was significantly reduced (from 19.4 to 5.9%), whereas congenital heart disease-associated IE had a tendency to increase (from 55.6 to 79.4%). Staphylococcus aureus was detected as the most common pathogenic microorganism, and its involvement tended to increase (from 32.0 to 58.5%), whereas the percentage of infections caused by Streptococcus viridans (8.0%) had not changed. It was interesting to note that the rate of vegetations detected was increased from 50.0 to 67.6% and the incidence of right-sided IE was also increased (from 35.0 to 60.9%). The most common valves involved in recent cases were tricuspid valves (increase from 30.0 to 47.8%), while mitral valve infection was reduced (from 60.0 to 39.1%). Penicillin was still the most commonly used antibiotic for the treatment of IE; the combination of penicillin plus cephalosporin has been recommended more and more recently. Conclusions: Comparing pediatric IE patients during the past 40 years, we found that the role of rheumatic heart disease as a predisposing factor is diminishing. Pediatric IE is still predominantly caused by staphylococci. The most commonly involved valves are tricuspid valves instead of mitral valves. Gram-positive bacteria showed an increased resistance to penicillin when used alone, and the use of combination treatment with antibiotics is increasing in the area.
Apolipoprotein E-Deficient Mice Are Susceptible to the Development of Acute Lung Injury
Authors: Yamashita Cory M. , Fessler Michael B. , Vasanthamohan Lakshman , Lac Joanne , Madenspacher Jennifer , McCaig Lynda , Yao Lijuan , Wang Lefeng , Puntorieri Valeria , Mehta Sanjay , Lewis Jim F. , Veldhuizen Ruud A.W.
Published: March 2014

Background: Apolipoprotein E (apoE) has been shown to play a pivotal role in the development of cardiovascular disease, attributable to its function in lipid trafficking and immune modulating properties; however, its role in modulating inflammation in the setting of acute lung injury (ALI) is unknown. Objective: To determine whether apoE-deficient mice (apoE-/-) are more susceptible to ALI compared to wild-type (WT) animals. Methods: Two independent models of ALI were employed. Firstly, WT and apoE-/- mice were randomized to acid aspiration (50 μl of 0.1 N hydrochloric acid) followed by 4 h of mechanical ventilation. Secondly, WT and apoE-/- mice were randomized to 72 h of hyperoxia exposure or room air. Thereafter, the intrinsic responses of WT and apoE-/- mice were assessed using the isolated perfused mouse lung (IPML) setup. Finally, based on elevated levels of oxidized low-density lipoprotein (oxLDL) in apoE-/-, the effect of oxLDL on lung endothelial permeability and inflammation was assessed. Results: In both in vivo models, apoE-/- mice demonstrated greater increases in lung lavage protein levels, neutrophil counts, and cytokine expression (p < 0.05) compared to WT mice. Experiments utilizing the IPML setup demonstrated no differences in intrinsic lung responses to injury between apoE-/- and WT mice, suggesting the presence of a circulating factor as being responsible for the in vivo observations. Finally, the exposure of lung endothelial cells to oxLDL resulted in increased monolayer permeability and IL-6 release compared to native (nonoxidized) LDL. Conclusions: Our findings demonstrate a susceptibility of apoE-/- animals to ALI that may occur, in part, due to elevated levels of oxLDL.
Amebic Liver Abscess: Fine Needle Aspiration Diagnosis
Authors: Mokhtari Maral , Kumar Perikala Vijayananda
Published: March 2014

Objective: To describe the findings in fine needle aspiration (FNA) of an amebic liver abscess (ALA). Study Design: Seven patients (6 men and 1 woman between 52 and 60 years of age) treated for amebic dysentery with multiple liver lesions were selected for ultrasound (US)-guided FNA. The clinical differential diagnosis was malignancy. Abdominal US of the patients revealed multiple, variably sized, well-defined, hypoechoic, cystic liver lesions. FNA of these lesions was performed. Results: Smears of the aspirated material showed necrotic material with mixed inflammatory cells and Entamoeba histolytica trophozoites consisting of round blue bodies with well-defined borders containing a single, eccentrically located nucleus with central karyosome and engulfed red blood cells in the cytoplasm. There were also Charcot-Leyden crystals. ALA was diagnosed. Conclusion: FNA can yield the correct diagnosis of ALA and allows early initiation of treatment. ALA should be considered in the differential diagnosis of space-occupying lesions of the liver.
Analysis of Nondiagnostic Results in a Large Series of Thyroid Fine-Needle Aspiration Cytology Performed over 9 Years in a Single Center
Authors: Ferreira Marta Almeida , Gerhard Rene , Schmitt Fernando
Published: March 2014

Objective: Thyroid fine-needle aspiration cytology (FNAC) is the most valuable, cost-effective and accurate method for the evaluation of patients with thyroid nodules. One of its limitations is that up to 20% of results are nondiagnostic or unsatisfactory. The aim of this study was to analyze the number of thyroid FNAC specimens with nondiagnostic results obtained on an outpatient basis and how many of these had to be repeated according to their results. Study Design: This was a retrospective analysis of diagnostic reports of nondiagnostic thyroid FNAC specimens obtained between 1 January 2004 and 31 December 2012 which were retrieved by means of a computerized search. The FNAC results and the age and sex of the patients were collected. Results: From a total of 15,292 thyroid FNAC specimens, 6.8% (n = 1,033) corresponded to nondiagnostic cases. Eligible diagnostic reports for analysis included 877 cases (106 were repetitions of previous nondiagnostic FNAC). After an initial nondiagnostic finding for 771 FNAC smears, 29.5% (n = 225) were repeated with the following results: 43.6% insufficient, 49.3% benign, 6.2% follicular neoplasm, 0.4% suspicious for malignancy and 0.4% malignant. Twenty-two patients underwent a second repeated FNAC. Here the findings were: 36.4% insufficient, 59.1% benign, 4.5% follicular neoplasm, 0.0% suspicious for malignancy and 0.0% malignant. Conclusions: There was a low rate of repeated FNAC among the group of nondiagnostic cases. With repeated FNAC, the rate of nondiagnostic cases and the number of results that potentially demand surgery diminish.
Long-Term Effects of Oral L-Carnitine Supplementation on Anemia in Chronic Hemodialysis
Authors: Kudoh Yasuo , Aoyama Shinya , Torii Takaaki , Chen Qijie , Nagahara Daigo , Sakata Hiromi , Nozawa Akihiko
Published: March 2014

Background: The therapeutic role of L-carnitine (LC) on the anemia of chronic hemodialized patients is still controversial. In order to clarify the long-term effects of LC administration on renal anemia, an open, observational 12-month study was performed. Methods: Twenty stable outpatients undergoing hemodialysis were administered LC 900 mg p.o. daily for 12 months. The recombinant human erythropoietin (rHuEPO) dose was adjusted monthly when necessary to maintain the target hemoglobin (Hb) levels. Results: The free LC level increased, while the acyl/free LC ratio decreased significantly 3 months after administration and was then maintained until the end of the study. There was no difference in Hb levels and the erythropoietin resistance index (ERI) during the study period. However, it was observed that ERI decreased significantly in 7 out of 18 patients (responders) 5 months after LC administration and was maintained thereafter (almost 40% reduction of the rHuEPO dose). The acyl/free carnitine ratio at baseline was the most contributing factor distinguishing responders from nonresponders. Conclusion: Although the beneficial effect of LC supplementation on renal anemia was not observed in all patients, at least 40% of the patients (responders) showed a significant improvement in ERI after long-term LC administration.
Xeroderma Pigmentosum/De Sanctis-Cacchione Syndrome: Unusual Cause of Ataxia
Authors: Fekete Robert
Published: March 2014

Introduction: Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder of DNA repair, with a prevalence of 1 in 1 million. It may also be a cause of neurological symptoms including sensorineural hearing loss, peripheral neuropathy, ataxia, and chorea. Severe neurological symptoms including mental retardation, short stature, and hypogonadism invoke De Sanctis-Cacchione syndrome (DCS). Case Report: The patient was a 55-year-old woman with a history of mental retardation who developed chorea at age 32 and ataxia at age 37. She had numerous facial scars from 10 prior basal cell carcinoma excisions as well as diminished deep tendon reflexes, bilateral hearing loss, dysphagia, and skin freckling. Brain MRI revealed severe cortical, cerebellar, and brainstem atrophy. Supportive treatment and prevention of further damage from UV light is the mainstay of treatment in XP and DCS. Conclusion: XP and related disorders should be considered in the setting of neurological disorder and multiple cutaneous cancers.
Simultaneous Occurrence of Early Gastric Carcinoma and Mucosa-Associated Lymphoid Tissue Lymphoma of the Omentum
Authors: Murakami Tomohiro , Shoji Tuyoshi , Suzuki Katsunori , Ishikawa Shintaro , Maruo Hirotoshi
Published: March 2014

The simultaneous association of gastric carcinoma with omental mucosa-associated lymphoid tissue (MALT) lymphoma is a rare event that has not been reported previously. We focused on the hypothetic pathogenetic mechanisms, diagnosis and treatment of this rare condition. A 55-year-old woman with Helicobacter pylori infection underwent distal gastrectomy in our hospital. Three independent early gastric cancers and a mass near the cecum were diagnosed preoperatively. Pathological review of the resected stomach showed three independent early signet ring cell gastric carcinomas, and the mass in the omentum near the cecum was shown to be omental MALT lymphoma. Due to the nature of the patient's disease, she was started on medical eradication of H. pylori. Synchronous gastric adenocarcinoma and omental MALT lymphoma is a rare event. Special attention given to H. pylori-associated gastric cancer patients can avoid misdiagnosis and lead to adequate treatment.
Interleukin-3/Granulocyte Macrophage Colony–Stimulating Factor Receptor Promotes Stem Cell Expansion, Monocytosis, and Atheroma Macrophage Burden in Mice With Hematopoietic
ApoE
Deficiency
Authors: Wang Mi , Subramanian Manikandan , Abramowicz Sandra , Murphy Andrew J. , Gonen Ayelet , Witztum Joseph , Welch Carrie , Tabas Ira , Westerterp Marit , Tall Alan R.
Published: March 2014

Objective—

Coronary heart disease is associated with monocytosis. Studies using animal models of monocytosis and atherosclerosis such as
ApoE
−/−
mice have shown bone marrow (BM) hematopoietic stem and multipotential progenitor cell (HSPC) expansion, associated with increased cell surface expression of the common β subunit of the granulocyte macrophage colony–stimulating factor/interleukin-3 receptor (CBS) on HSPCs.
ApoE
−/−
mice also display increased granulocyte macrophage colony–stimulating factor–dependent monocyte production in the spleen. We investigated the role of the CBS in cholesterol-driven HSPC expansion, monocytosis, and atherosclerosis.

Approach and Results—

Ldlr
−/−
mice were transplanted with
ApoE
−/−
Cbs
−/−
or
ApoE
−/−
BM followed by Western-type diet feeding. Compared with
ApoE
−/−
BM–transplanted controls,
ApoE
−/−
Cbs
−/−
BM–transplanted mice had reduced BM and splenic HSPC proliferation, fewer blood monocytes and neutrophils, and reduced macrophage content and area of early atherosclerotic lesions. More advanced lesions showed diminished macrophage and collagen content; however, lesion size was unchanged, reflecting an increase in necrotic core area, associated with a marked decrease in
Abcg1
expression and increased macrophage apoptosis. Compared with wild-type mice, Western-type diet–fed
ApoE
−/−
mice showed increased CBS expression on granulocyte macrophage colony–stimulating factor–producing innate response activator B cells and expansion of this population.
ApoE
−/−
Cbs
−/−
BM–transplanted
Ldlr
−/−
mice showed a marked decrease in innate response activator B cells compared with
ApoE
−/−
BM–transplanted
Ldlr
−/−
controls.

Conclusions—

Increased levels of CBS on HSPCs and splenic innate response activator B cells lead to expansion of these populations in
ApoE
−/−
BM–transplanted
Ldlr
−/−
mice, contributing to monocytosis and increased lesional macrophage content. However, in more advanced lesions, the CBS also has a role in atherosclerotic plaque stabilization.
Optical Bedside Monitoring of Cerebral Blood Flow in Acute Ischemic Stroke Patients During Head-of-Bed Manipulation
Authors: Favilla Christopher G. , Mesquita Rickson C. , Mullen Michael , Durduran Turgut , Lu Xiangping , Kim Meeri N. , Minkoff David L. , Kasner Scott E. , Greenberg Joel H. , Yodh Arjun G. , Detre John A.
Published: March 2014

Background and Purpose—

A primary goal of acute ischemic stroke (AIS) management is to maximize perfusion in the affected region and surrounding ischemic penumbra. However, interventions to maximize perfusion, such as flat head-of-bed (HOB) positioning, are currently prescribed empirically. Bedside monitoring of cerebral blood flow (CBF) allows the effects of interventions such as flat HOB to be monitored and may ultimately be used to guide clinical management.

Methods—

Cerebral perfusion was measured during HOB manipulations in 17 patients with unilateral AIS affecting large cortical territories in the anterior circulation. Simultaneous measurements of frontal CBF and arterial flow velocity were performed with diffuse correlation spectroscopy and transcranial Doppler ultrasound, respectively. Results were analyzed in the context of available clinical data and a previous study.

Results—

Frontal CBF, averaged over the patient cohort, decreased by 17% (
P
=0.034) and 15% (
P
=0.011) in the ipsilesional and contralesional hemispheres, respectively, when HOB was changed from flat to 30°. Significant (cohort-averaged) changes in blood velocity were not observed. Individually, varying responses to HOB manipulation were observed, including paradoxical increases in CBF with increasing HOB angle. Clinical features, stroke volume, and distance to the optical probe could not explain this paradoxical response.

Conclusions—

A lower HOB angle results in an increase in cortical CBF without a significant change in arterial flow velocity in AIS, but there is variability across patients in this response. Bedside CBF monitoring with diffuse correlation spectroscopy provides a potential means to individualize interventions designed to optimize CBF in AIS.
Branching Patterns Determine the Size of Single Subcortical Infarctions
Authors: Kim Bum Joon , Lee Deok Hee , Kang Dong-Wha , Kwon Sun U. , Kim Jong S.
Published: March 2014

Background and Purpose—

The size variation of single subcortical infarcts (SSIs) may be because of differences in stroke mechanisms or branching patterns of perforators. We aim to investigate this issue using high-resolution MRI.

Methods—

Patients with high-resolution MRI–identified SSI without significant (≥50%) middle cerebral artery stenosis were enrolled. Perforator stems were defined as perforators originating from the middle cerebral artery and perforator branches as linear structures inside the infarcted area, traceable from >2 adjacent slices. The branching index was calculated as the number of perforator branches divided by the number of perforator stems. Clinical and imaging characteristics were compared between large (≥20 mm in diameter) and small SSI groups.

Results—

Forty-one patients (10 large and 31 small SSIs) were enrolled. Larger SSIs were more closely associated with diabetes mellitus and severe neurological dysfunction but not with the presence of middle cerebral artery plaque. Although there was no difference in the number of perforator stems, the number of perforator branches (4.8±2.2 versus 2.3±1.4;
P
=0.005) and branching index (2.9±1.0 versus 1.2±0.8;
P
<0.001) was higher in the large SSI group. SSI diameter showed a significant correlation with the number of perforator branches (
r
=0.630;
P
<0.001) and branching index (
r
=0.750;
P
<0.001).

Conclusions—

SSI diameter seems to be associated with anatomic branching variation rather than the mechanism of stroke. Definition of small vessel disease with lesion diameter criteria may not be appropriate.
Multiplicative Approximations, Optimal Hypervolume Distributions, and the Choice of the Reference Point
Authors: Friedrich Tobias , Neumann Frank , Thyssen Christian
Published: March 2014

Many optimization problems arising in applications have to consider several objective functions at the same time. Evolutionary algorithms seem to be a very natural choice for dealing with multi-objective problems as the population of such an algorithm can be used to represent the trade-offs with respect to the given objective functions. In this paper, we contribute to the theoretical understanding of evolutionary algorithms for multi-objective problems. We consider indicator-based algorithms whose goal is to maximize the hypervolume for a given problem by distributing [Formula: see text] points on the Pareto front. To gain new theoretical insights into the behavior of hypervolume-based algorithms, we compare their optimization goal to the goal of achieving an optimal multiplicative approximation ratio. Our studies are carried out for different Pareto front shapes of bi-objective problems. For the class of linear fronts and a class of convex fronts, we prove that maximizing the hypervolume gives the best possible approximation ratio when assuming that the extreme points have to be included in both distributions of the points on the Pareto front. Furthermore, we investigate the choice of the reference point on the approximation behavior of hypervolume-based approaches and examine Pareto fronts of different shapes by numerical calculations.
Pempheris bexillon, a new species of sweeper (Teleostei: Pempheridae) from the Western Indian Ocean
Authors: MOOI RANDALL D. , RANDALL JOHN E.
Published: March 2014

Pempheris bexillon new species is described from the 129 mm SL holotype and 11 paratypes (119–141 mm SL) from the Comoro Islands. Twelve other specimens have been examined from the Agaléga Islands, Mascarene Islands, and Bassas da India (Madagascar). It is differentiated from other Pempheris by the following combination of characters: a yellow dorsal fin with a black, distal margin along its full length, broadest on anterior rays (pupil-diameter width) and gradually narrowing posteriorly, the last ray with only a black tip; large, deciduous cycloid scales on the flank; dark, oblong spot on the pectoral-fin base; anal fin with a dark margin; segmented anal-fin rays 38–45 (usually >40); lateral-line scales 56–65; and total gill rakers on the first arch 31–35; iris reddish-brown. Tables of standard meristic and color data for type material of all nominal species of cycloid-scaled Pempheris in the Indo-Pacific are provided.
Sattleria revisited: unexpected cryptic diversity on the Balkan Peninsula and in the south-eastern Alps (Lepidoptera: Gelechiidae)
Authors: HUEMER PETER , TIMOSSI GIOVANNI
Published: March 2014

The taxonomy of Sattleria Povolný from the high mountain systems on the Balkan Peninsula and the adjacent parts of the Alps (south-eastern Alps, Dinaric Alps, Rila Mountains) is revised based on recently collected material and re-examined museum vouchers. Adult morphology and molecular data of the COI barcode region support the existence of six strictly allopatric species in this area, including four new species: Sattleria sophiae Timossi, sp. nov. (Parco Paneveggio—Pale di San Martino, Dolomites, Prov. Trento, Italy), Sattleria dolomitica Huemer, sp. nov. (Eastern Dolomites, Prov. South Tyrol, Italy), Sattleria dinarica Huemer, sp. nov. (Durmitor NP, Dinaric Alps, Montenegro) and Sattleria haemusi Huemer, sp. nov. (Rila Mts., Bulgaria; Šar Planina, Macedonia).