bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of A-kinase anchoring proteins in cardiac oxidative stress
Authors: Diviani Dario , Osman Halima , Delaunay Marion , Kaiser Simon
Published: October 2019

Cardiac stress initiates a pathological remodeling process that is associated with cardiomyocyte loss and fibrosis that ultimately leads to heart failure. In the injured heart, a pathologically elevated synthesis of reactive oxygen species (ROS) is the main driver of oxidative stress and consequent cardiomyocyte dysfunction and death. In this context, the cAMP-dependent protein kinase (PKA) plays a central role in regulating signaling pathways that protect the heart against ROS-induced cardiac damage. In cardiac cells, spatiotemporal regulation of PKA activity is controlled by A-kinase anchoring proteins (AKAPs). This family of scaffolding proteins tether PKA and other transduction enzymes at subcellular microdomains where they can co-ordinate cellular responses regulating oxidative stress. In this review, we will discuss recent literature illustrating the role of PKA and AKAPs in modulating the detrimental impact of ROS production on cardiac function.
Selective small-molecule EPAC activators
Authors: Luchowska-Stańska Urszula , Morgan David , Yarwood Stephen J. , Barker Graeme
Published: October 2019

The cellular signalling enzymes, EPAC1 and EPAC2, have emerged as key intracellular sensors of the secondary messenger cyclic 3′,5′-adenosine monophosphate (cyclic adenosine monophosphate) alongside protein kinase A. Interest has been galvanised in recent years thanks to the emergence of these species as potential targets for new cardiovascular disease therapies, including vascular inflammation and insulin resistance in vascular endothelial cells. We herein summarise the current state-of-the-art in small-molecule EPAC activity modulators, including cyclic nucleotides, sulphonylureas, and N-acylsulphonamides.
Making the cut(s): how Cas12a cleaves target and non-target DNA
Authors: Swarts Daan C.
Published: October 2019

CRISPR–Cas12a (previously named Cpf1) is a prokaryotic deoxyribonuclease that can be programmed with an RNA guide to target complementary DNA sequences. Upon binding of the target DNA, Cas12a induces a nick in each of the target DNA strands, yielding a double-stranded DNA break. In addition to inducing cis-cleavage of the targeted DNA, target DNA binding induces trans-cleavage of non-target DNA. As such, Cas12a–RNA guide complexes can provide sequence-specific immunity against invading nucleic acids such as bacteriophages and plasmids. Akin to CRISPR–Cas9, Cas12a has been repurposed as a genetic tool for programmable genome editing and transcriptional control in both prokaryotic and eukaryotic cells. In addition, its trans-cleavage activity has been applied for high-sensitivity nucleic acid detection. Despite the demonstrated value of Cas12a for these applications, the exact molecular mechanisms of both cis- and trans-cleavage of DNA were not completely understood. Recent studies have revealed mechanistic details of Cas12a-mediates DNA cleavage: base pairing of the RNA guide and the target DNA induces major conformational changes in Cas12a. These conformational changes render Cas12a in a catalytically activated state in which it acts as deoxyribonuclease. This deoxyribonuclease activity mediates cis-cleavage of the displaced target DNA strand first, and the RNA guide-bound target DNA strand second. As Cas12a remains in the catalytically activated state after cis-cleavage, it subsequently demonstrates trans-cleavage of non-target DNA. Here, I review the mechanistic details of Cas12a-mediated cis- and trans-cleavage of DNA. In addition, I discuss how bacteriophage-derived anti-CRISPR proteins can inhibit Cas12a activity.
Extracellular matrix: the gatekeeper of tumor angiogenesis
Authors: Mongiat Maurizio , Buraschi Simone , Andreuzzi Eva , Neill Thomas , Iozzo Renato V.
Published: October 2019

The extracellular matrix is a network of secreted macromolecules that provides a harmonious meshwork for the growth and homeostatic development of organisms. It conveys multiple signaling cascades affecting specific surface receptors that impact cell behavior. During cancer growth, this bioactive meshwork is remodeled and enriched in newly formed blood vessels, which provide nutrients and oxygen to the growing tumor cells. Remodeling of the tumor microenvironment leads to the formation of bioactive fragments that may have a distinct function from their parent molecules, and the balance among these factors directly influence cell viability and metastatic progression. Indeed, the matrix acts as a gatekeeper by regulating the access of cancer cells to nutrients. Here, we will critically evaluate the role of selected matrix constituents in regulating tumor angiogenesis and provide up-to-date information concerning their primary mechanisms of action.
GDF11 impairs liver regeneration in mice after partial hepatectomy
Authors: Wang Wenjie , Yang Xiao , Yang Jiankun , Liu Shenpei , Lv Yongman , Zhang Cuntai , Dong Wei , Liu Anding
Published: October 2019

Growth differentiation factor 11 (GDF11) is a member of the transforming growth factor (TGF)-β superfamily. The rejuvenative effect of GDF11 has been called into question recently, and its role in liver regeneration is unclear. Here, we investigated the pathophysiologic role of GDF11, as well as its plausible signaling mechanisms in a mouse model of partial hepatectomy (PH). We demonstrated that both serum and hepatic GDF11 protein expression increased following PH. Treatment with adeno-associated viruses-GDF11 and recombinant GDF11 protein severely impaired liver regeneration, whereas inhibition of GDF11 activity with neutralizing antibodies significantly improved liver regeneration after PH. In vitro, GDF11 treatment significantly delayed cell proliferation and induced cell-cycle arrest in α mouse liver 12 (AML12) cells. Moreover, GDF11 activated TGF-β-SMAD2/3 signaling pathway. Inhibition of GDF11-induced SMAD2/3 activity significantly blocked GDF11-mediated reduction in cell proliferation both in vivo and in vitro. In the clinical setting, GDF11 levels were significantly elevated in patients after hepatectomy. Collectively, these results indicate that rather than a ‘rejuvenating’ agent, GDF11 impairs liver regeneration after PH. Suppression of cell-cycle progression via TGF-β-SMAD2/3 signaling pathway may be a key mechanism by which GDF11 inhibits liver regeneration.
Endogenous hydrogen sulfide sulfhydrates IKKβ at cysteine 179 to control pulmonary artery endothelial cell inflammation
Authors: Zhang Da , Wang Xiuli , Chen Siyao , Chen Selena , Yu Wen , Liu Xin , Yang Guosheng , Tao Yinghong , Tang Xinjing , Bu Dingfang , Zhang Heng , Kong Wei , Tang Chaoshu , Huang Yaqian , Du Junbao , Jin Hongfang
Published: October 2019

Background: Pulmonary artery endothelial cell (PAEC) inflammation is a critical event in the development of pulmonary arterial hypertension (PAH). However, the pathogenesis of PAEC inflammation remains unclear.

Methods: Purified recombinant human inhibitor of κB kinase subunit β (IKKβ) protein, human PAECs and monocrotaline-induced pulmonary hypertensive rats were employed in the study. Site-directed mutagenesis, gene knockdown or overexpression were conducted to manipulate the expression or activity of a target protein.

Results: We showed that hydrogen sulfide (H2S) inhibited IKKβ activation in the cell model of human PAEC inflammation induced by monocrotaline pyrrole-stimulation or knockdown of cystathionine γ-lyase (CSE), an H2S generating enzyme. Mechanistically, H2S was proved to inhibit IKKβ activity directly via sulfhydrating IKKβ at cysteinyl residue 179 (C179) in purified recombinant IKKβ protein in vitro, whereas thiol reductant dithiothreitol (DTT) reversed H2S-induced IKKβ inactivation. Furthermore, to demonstrate the significance of IKKβ sulfhydration by H2S in the development of PAEC inflammation, we mutated C179 to serine (C179S) in IKKβ. In purified IKKβ protein, C179S mutation of IKKβ abolished H2S-induced IKKβ sulfhydration and the subsequent IKKβ inactivation. In human PAECs, C179S mutation of IKKβ blocked H2S-inhibited IKKβ activation and PAEC inflammatory response. In pulmonary hypertensive rats, C179S mutation of IKKβ abolished the inhibitory effect of H2S on IKKβ activation and pulmonary vascular inflammation and remodeling.

Conclusion: Collectively, our in vivo and in vitro findings demonstrated, for the first time, that endogenous H2S directly inactivated IKKβ via sulfhydrating IKKβ at Cys179 to inhibit nuclear factor-κB (NF-κB) pathway activation and thereby control PAEC inflammation in PAH.
SETD3 is regulated by a couple of microRNAs and plays opposing roles in proliferation and metastasis of hepatocellular carcinoma
Authors: Xu Liangliang , Wang Peng , Feng Xinfu , Tang Jianwei , Li Lian , Zheng Xiaobo , Zhang Jinfu , Hu Yitao , Lan Tian , Yuan Kefei , Zhang Yanfang , Ren Shengsheng , Hao Xiangyong , Zhang Ming , Xu Mingqing
Published: October 2019

A previous study reported that histone methyltransferase SETD3 is up-regulated in tumor tissues of hepatocellular carcinoma (HCC) and is associated with the growth of HCC. However, the clinical significance and the effect of SETD3 on HCC metastasis remain unclear. In the present study, both the protein and mRNA expression levels of SETD3 were measured in a larger cohort of HCC patients. The results showed that the protein level of SETD3 in HCC tissues was significantly higher than that in non-tumorous tissues, which was inconsistent with the mRNA expression level of SETD3. The high protein level of SETD3 in HCC tissues was significantly associated with male gender, poor pathological differentiation, liver cirrhosis and unfavorable prognosis of HCC patients. Subsequently, we demonstrated that SETD3 could be regulated at post-transcriptional step by a couple of miRNAs (miR-16, miR-195 and miR-497). Additionally, in vitro and in vivo experiments revealed that SETD3 played opposing roles in proliferation and metastasis of HCC: promoting proliferation but inhibiting metastasis. Mechanistic experiments revealed that doublecortin-like kinase 1 (DCLK1) was a downstream target of SETD3. SETD3 could increase the DNA methylation level of DCLK1 promoter to inhibit the transcription of DCLK1. Further study revealed that DCLK1/PI3K/matrix metalloproteinase (MMP) 2 (MMP-2) was an important pathway that mediated the effect of SETD3 on HCC metastasis. In conclusion, the present study revealed that SETD3 is associated with tumorigenesis and is a promising biomarker for predicting the prognosis of HCC patients after surgical resection. In addition, SETD3 plays inhibitory role in HCC metastasis partly through DCLK1/PI3K/MMP-2 pathway.
A novel function for HEG1 in promoting metastasis in hepatocellular carcinoma
Authors: Dewdney Brittany , Hebbard Lionel
Published: October 2019

Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related deaths around the globe. For patients receiving liver tumour resection, the risk of reoccurrence and metastasis is high. Cancer metastasis can occur as a consequence of a physical change known as epithelial to mesenchymal transition (EMT). In this instance, cancer cells acquire migratory and invasive characteristics that allow the cells to move into adjacent tissue or enter the bloodstream to reach a secondary site, where they begin to form a new tumour. Targetting proteins involved in the signalling pathways that induce the mesenchymal phenotype has been an ongoing field of research. A recently published study has described a novel role for the heart development protein with EGF-like domains (HEG1) in promoting EMT. This research provides new insights into the biological function of this protein in HCC. Furthermore, the research indicates a new target for future prognostic and therapeutic research in HCC.
Keratin intermediate filaments: intermediaries of epithelial cell migration
Authors: Yoon Sungjun , Leube Rudolf E.
Published: October 2019

Migration of epithelial cells is fundamental to multiple developmental processes, epithelial tissue morphogenesis and maintenance, wound healing and metastasis. While migrating epithelial cells utilize the basic acto-myosin based machinery as do other non-epithelial cells, they are distinguished by their copious keratin intermediate filament (KF) cytoskeleton, which comprises differentially expressed members of two large multigene families and presents highly complex patterns of post-translational modification. We will discuss how the unique mechanophysical and biochemical properties conferred by the different keratin isotypes and their modifications serve as finely tunable modulators of epithelial cell migration. We will furthermore argue that KFs together with their associated desmosomal cell–cell junctions and hemidesmosomal cell–extracellular matrix (ECM) adhesions serve as important counterbalances to the contractile acto-myosin apparatus either allowing and optimizing directed cell migration or preventing it. The differential keratin expression in leaders and followers of collectively migrating epithelial cell sheets provides a compelling example of isotype-specific keratin functions. Taken together, we conclude that the expression levels and specific combination of keratins impinge on cell migration by conferring biomechanical properties on any given epithelial cell affecting cytoplasmic viscoelasticity and adhesion to neighboring cells and the ECM.
Relay selection algorithm based on social network combined with Q‐learning for vehicle D2D communication
Authors: Qian Hongzhi , Yu Jinming , Hua Licheng
Published: October 2019

A relay selection algorithm was proposed to improve a communication rate of D2D (device‐to‐device) users in‐vehicle networking communication systems based on social network combined with Q‐learning. The scheme was divided into two steps. Firstly, a social threshold was introduced to filter the potential relay nodes to reduce the number of probing times based on the user's interest similarity in D2D communication network. Then, an optimal relay selection algorithm was proposed to maximise the total rate of D2D links based on a Q‐learning algorithm. This method can provide the optimal relay selection scheme to meet the requirements of vehicle networking communication. The simulation results showed that the proposed scheme could reduce the number of probing relays and improve the communication speed of the system on the basis of ensuring communication security.
Extinction angle predictive control strategy for commutation failure mitigation in HVDC systems considering voltage distortion
Authors: Liu Lei , Lin Sheng , Liao Kai , Sun Peiyao , Deng Yujia , Li Xiaopeng , He Zhengyou
Published: October 2019

In this study, an extinction angle predictive (EAP) control strategy is proposed to mitigate commutation failure (CF) in high voltage direct current (HVDC) systems. The proposed strategy works effectively during both AC system faults and commutation voltage distortions. At first, an index is put forward to evaluate the prospective commutation area drop and quantify the upcoming commutation stress considering the commutation mechanism. Then, the extinction angle is predicted based on the detected commutation area drop incident. Further, the predicted extinction angle is introduced into the HVDC inverter control to design the EAP control strategy, ensuring that the CF can be prevented due to a sufficient commutation margin. The advantage of the proposed strategy is that it evaluates the upcoming commutation stress based on the transient commutation voltage waveform. Thus, a better sensitivity for commutation voltage distortion can be ensured. The proposed strategy is simulated in the PSCAD/EMTDC platform and the results are compared with that of the conventional schemes, verifying the performance of the proposed strategy in mitigating the CF during AC faults and voltage distortion.
Development of platoon‐based actuated signal control systems to coordinated intersections: application in corridors in Houston
Authors: Wu Xing , Yang Hao , Mainali Bipul , Pokharel Pratik , Chiu Steve
Published: October 2019

A signal control method considering platoon‐based actuation is presented with a focus on its application to two arterial corridors in the Houston Metropolitan Area, where the signal coordination is required for adjacent intersections. For the purpose of immediate implementation, the system was developed based on existing conventional loop detectors and control technologies used by Texas Department of Transportation. Simply based on volume and occupancy – the only traffic information reported by a conventional loop detector, it is impossible to precisely detect a platoon of vehicle approaching an intersection. As a compromise way, two specific logics were proposed to switch the system between the original coordinated control and the new platoon‐based actuated control systems. At one testbed suffering from large left‐turn traffic, the results revealed by the detector data before and after the implementation show that the model works well to relieve the delay for both left‐turn traffic and through traffic on the major road. On another testbed where the platoon‐based control is activated only when the through traffic is not high, some improvements were also observed. This method opens the door of wide application of the platoon‐based signal control system (simply based on conventional loop detectors) to arterial corridors.
Precision requirements for interferometric gridding in the analysis of a 21 cm power spectrum
Authors: Offringa A. R. , Mertens F. , van der Tol S. , Veenboer B. , Gehlot B. K. , Koopmans L. V. E. , Mevius M.
Published: October 2019

Context. Experiments that try to observe the 21 cm redshifted signals from the epoch of reionisation (EoR) using interferometric low-frequency instruments have stringent requirements on the processing accuracy.

Aims. We analyse the accuracy of radio interferometric gridding of visibilities with the aim to quantify the power spectrum bias caused by gridding. We do this ultimately to determine the suitability of different imaging algorithms and gridding settings for an analysis of a 21 cm power spectrum.

Methods. We simulated realistic Low-Frequency Array (LOFAR) data and constructed power spectra with convolutional gridding and w stacking, w projection, image-domain gridding, and without w correction. These were compared against data that were directly Fourier transformed. The influence of oversampling, kernel size, w-quantization, kernel windowing function, and image padding were quantified. The gridding excess power was measured with a foreground subtraction strategy, for which foregrounds were subtracted using Gaussian progress regression, as well as with a foreground avoidance strategy.

Results. Constructing a power spectrum with a significantly lower bias than the expected EoR signals is possible with the methods we tested, but requires a kernel oversampling factor of at least 4000, and when w-correction is used, at least 500 w-quantization levels. These values are higher than typically used values for imaging, but they are computationally feasible. The kernel size and padding factor parameters are less crucial. Of the tested methods, image-domain gridding shows the highest accuracy with the lowest imaging time.

Conclusions. LOFAR 21 cm power spectrum results are not affected by gridding. Image-domain gridding is overall the most suitable algorithm for 21 cm EoR power spectrum experiments, including for future analyses of data from the Square Kilometre Array (SKA) EoR. Nevertheless, convolutional gridding with tuned parameters results in sufficient accuracy for interferometric 21 cm EoR experiments. This also holds for w stacking for wide-field imaging. The w-projection algorithm is less suitable because of the requirements for kernel oversampling, and a faceting approach is unsuitable because it causes spatial discontinuities.
Bondi accretion for adiabatic flows onto a massive black hole with an accretion disc
Authors: Ramírez-Velásquez J. M. , Sigalotti L. Di G. , Gabbasov R. , Klapp J. , Contreras E.
Published: October 2019

We present the classical Bondi accretion theory for the case of non-isothermal accretion processes onto a supermassive black hole (SMBH), including the effects of X-ray heating and the radiation force due to electron scattering and spectral lines. The radiation field is calculated by considering an optically thick, geometrically thin, standard accretion disc as the emitter of UV photons and a spherical central object as a source of X-ray emission. In our analysis, the UV emission from the accretion disc is assumed to have an angular dependence, and the X-ray radiation from the central object is assumed to be isotropic. This allows us to build streamlines in any angular direction. The influence of both types of radiation is evaluated for different flux fractions of the X-ray and UV emissions with and without the effects of spectral line driving. We find that the radiation emitted near the SMBH interacts with the infalling matter and modifies the accretion dynamics. In the presence of line driving, a transition takes place from pure type 1 and 2 to type 5 solutions, which takes place regardless of whether the UV emission dominates the X-ray emission. We computed the radiative factors at which this transition occurs, and discard type 5 solution from all our models. We also provide estimated values of the accretion radius and accretion rate in terms of the classical Bondi values. The results are useful for constructing proper initial conditions for time-dependent hydrodynamical simulations of accretion flows onto SMBHs at the centre of galaxies.
The impact of thermal winds on the outburst lightcurves of black hole X-ray binaries
Authors: Dubus Guillaume , Done Chris , Tetarenko Bailey E. , Hameury Jean-Marie
Published: October 2019

Context. The observed signatures of winds from X-ray binaries are broadly consistent with thermal winds, which are driven by X-ray irradiation of the outer accretion disc. Thermal winds produce mass outflow rates that can exceed the accretion rate in the disc.

Aims. We aim to study the impact of thermal wind mass loss on the stability and lightcurves of black hole X-ray binaries subject to the thermal-viscous instability driving their outbursts. Strong mass loss could stop outbursts early, as proposed for the 2015 outburst of V404 Cyg.

Methods. We used an analytical model for thermal (Compton) wind mass loss as a function of radius, X-ray spectrum, and luminosity that was calibrated against numerical simulations. We also estimated the fraction of the X-rays, emitted close to the compact object, that are scattered back to the outer disc in the wind. Scattering in the thermal wind couples irradiation to the disc size and inner mass accretion rate. The disc evolution equations were modified to include this wind mass loss and the varying irradiation fraction.

Results. Scattering in the strong wind expected of long Porb systems enhances the irradiation heating of the outer disc, keeping it stable against the thermal-viscous instability. This accounts very well for the existence of persistently bright systems with large discs, such as Cyg X-2, 1E 1740.7−2942, or GRS 1758−258. Mass loss from the thermal wind shortens the outburst, as expected, but it is insufficient in explaining the rapid decay timescale of black-hole X-ray binary outbursts. However, including the wind-related varying irradiation fraction produces lightcurves with plateaus in long Porb systems like GRO J1655−40. Plateau lightcurves may be a dynamical signature of enhanced irradiation due to scattering in thermal winds.

Conclusions. Mass loss due to thermal winds is not a major driver for the outburst dynamics up to luminosities of 0.1 − 0.2 LEdd. Higher luminosities may produce stronger mass loss but studying them is complicated since the wind becomes opaque. Magnetic winds, which extract angular momentum with little mass loss, seem more promising to explain the fast decay timescales generically seen in black-hole X-ray binaries. Thermal winds can play an important role in the outburst dynamics through the varying irradiation heating. This may be evidenced by relating changes in wind properties, X-ray spectra, or luminosity with changes in the optical emission that traces the outer disc. Simulations should enable more accurate estimates of the dependence of the irradiation onto the disc as a function of irradiation spectrum, radius, and disc wind properties.
Tracing Hercules in Galactic azimuth with Gaia DR2
Authors: Monari G. , Famaey B. , Siebert A. , Bienaymé O. , Ibata R. , Wegg C. , Gerhard O.
Published: October 2019

The second data release of the Gaia mission has revealed, in stellar velocity and action space, multiple ridges, the exact origin of which is still debated. Recently, we demonstrated that a large Galactic bar with pattern speed 39 km s−1 kpc−1 creates most of the observed ridges. Among these ridges, the Hercules moving group would then be associated with orbits trapped at the co-rotation resonance of the bar. Here we show that a distinctive prediction of such a model is that the angular momentum of Hercules at the Sun’s radius must significantly decrease with increasing Galactocentric azimuth (i.e. when getting closer to the major axis of the bar). We show that this dependence of the angular momentum of trapped orbits on the azimuth on the other hand does not happen close to the outer Lindblad resonance of a faster bar, unless the orbital distribution is still far from phase-mixed, namely for a bar perturbation younger than ∼2 Gyr. Using Gaia DR2 and Bayesian distances from the StarHorse code, and tracing the average Galactocentric radial velocity as a function of angular momentum and azimuth, we show that the Hercules angular momentum changes significantly with azimuth as expected for the co-rotation resonance of a dynamically old large bar.
Optimierung der Adhärenz von Patienten nach Nierentransplantation
Authors: Matevossian Edouard , Miksch Rainer Christoph
Published: October 2019

Eine mangelnde Adhärenz bzw. Compliance in der Arzneimitteltherapie kann eine erhöhte Morbidität und Mortalität sowie gewaltige Kosten im Gesundheitssystem verursachen. Fördernde Maßnahmen zur Adhärenz bzw. Compliance können in der Arzneimitteltherapie mit langfristig positivem Effekt auf den Therapieerfolg angewendet werden. Die Gemeinsamkeit aller dieser Interventionen liegt in einem gehäuften gezielten Kontakt von Leistungserbringern im Gesundheitssystem und Patienten im Laufe der Therapie hinsichtlich ihrer Adhärenz bzw. Compliance. Da die Prävalenz chronischer Erkrankungen in den nächsten Jahrzehnten weiter zunehmen wird, sind Maßnahmen zur Verbesserung der Adhärenz wichtig, um die Gesundheit der Bevölkerung nachhaltig zu verbessern – aber auch, um die Kosten für die Gesundheitssysteme nicht weiter explodieren zu lassen.
Imaging Spectrum of Pediatric Nonspecific Aortoarteritis on CT Angiography: A Retrospective Study
Authors: Verma Ashish , Kumar Ishan , Aggarwal Priyanka , Shukla Ram C.
Published: October 2019

Introduction

Takayasu's arteritis, a chronic, idiopathic, inflammatory panarteritis, is the major cause of Aortoarteritis in pediatric age group. The purpose of this study is to analyze the patterns of involvement and imaging findings of pediatric Takayasu's arteritis.

Materials and Methods

We retrospectively reviewed the CT angiographic images of 11 pediatric cases reported as “Takayasu's arteritis” or “nonspecific arteritis” over the period of last 3 years.

Results

Mural thickening with luminal stenosis was the most common findings. Aneurysmal dilatation of the descending thoracic aorta was observed in one case. Vessel stenoses without mural thickening, thrombosis and collateral vessel formation were the other findings. Pattern of involvement ranged from variable involvement of thoracic and abdominal aorta and their branches.

Conclusion

Awareness of its CT angiographic appearances and distribution pattern can help the clinicians and radiologists to have high index of suspicion in aiding early diagnosis and better management of this disease.
Cutaneous Anthrax—Still a Reality in India
Authors: Thappa Devinder Mohan
Published: October 2019

Anthrax, a toxigenic zoonosis, incidentally affecting humans has become rare but endemic outbreaks still continue to occur in tropical countries like India, parts of South America, and Europe where veterinary control of livestock is marginal and environmental conditions favor an animal–soil–animal cycle. India, with its largest population of livestock in the world, continues to have anthrax outbreaks with highest incidence reported from south, and the authors have reported an outbreak of 23 cases from 1998 to 2001 from south India. Children outnumbered adults and most of them had lesions on the exposed sites. However, there is a limited documentation of anthrax outbreaks from India warranting the need for sensitizing and creating awareness among health care professionals to identify and report these cases at the earliest so that appropriate actions are taken. Anthrax continues to retain a certain fascination and notoriety because of the potential for use of the bacillus spores in biologic warfare.
Success and Challenges in the Management of Chronic Myeloid Leukemia
Authors: Tripathi Anil Kumar
Published: October 2019

Chronic myeloid leukemia (CML) is one of the most common myeloproliferative neoplasms characterized by the presence of Philadelphia chromosome, that is, t(9:22), a reciprocal translocation between long arms of chromosomes 9 and 22. In its natural course CML has three phases, that is, chronic phase, accelerated phase, and blast crises phase. Peripheral blood shows marked leukocytosis and left shift. Diagnosis is confirmed by demonstration of specific molecular abnormality by polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH) method or cytogenetics. The drug of choice is tyrosine kinase inhibitor (TKI); imatinib. Other TKIs are dasatinib and nilotinib. Most patients respond and have almost normal life span. However, challenges remain. At present the drug is prescribed for lifelong. Recent studies have shown that the drug may be stopped in certain groups of which around 50% remain in long term remission (operational cure). However, around 20% did not respond and showed resistance. Research is in progress to find out the mechanism of resistance and newer therapeutic modalities or agents.
Corrections to the Landau kinetic equation for a weakly dissipative randomly driven system and the fluctuation-dissipation theorem
Authors: Gorev V. N. , Sokolovsky A. I.
Published: October 2019

This paper is devoted to the derivation of a kinetic equation for many-body one-component dissipative systems in an external random field. The system under consideration was discussed in the recent paper by Sliusarenko et al. [J. Math. Phys. 56, 043302 (2015)], where a generalization of the Vlasov kinetic equation was obtained. The potential interaction is assumed to be small (the corresponding small parameter λ), the dissipation interactions and the correlation functions of the external random field are considered as small quantities estimated by one small parameter μ for the simplicity. The kinetic equation is obtained up to the terms of the orders λ2μ0, λ1μ1, λ0μ2 inclusive. In weakly spatially nonuniform states of the system, this gives corrections to the Landau–Vlasov kinetic equation caused by the dissipation and external random field. In the case λ ≫ μ after the mean free time, the system reaches a state approximately described by the Maxwell distribution. The dissipation and random field will lead to the evolution of the system temperature. A time evolution equation for the temperature in spatially uniform states is derived on the basis of the obtained kinetic equation by a generalized Chapman–Enskog method which takes into account that the kinetic equation is an approximate one. This temperature time evolution equation is investigated up to the terms of the order μ3 inclusive. It is shown that under some conditions the final stage of the system evolution is a steady state. A fluctuation-dissipation theorem for this state is discussed. In this steady state, the system is described by a distribution function that contains corrections to the Maxwell distribution.
Informational analysis of Langevin equation of friction in earthquake rupture processes
Authors: Wu T.-H. , Chen C.-C. , Lovallo M. , Telesca L.
Published: October 2019

In this paper, we analyze the informational properties of time series of slip velocity generated by the Langevin equation of friction in two different frictional regimes: viscous and Coulombian. Representing the generated time series in the Fisher-Shannon plane (where the coordinate axes are the Fisher Information Measure and the Shannon entropy power), the two different frictional regimes are well discriminated. In particular, the viscous regime is characterized by smaller Shannon entropy than the Coulombian one. Furthermore, also the Fisher Information Measure of the slip velocity smoothed by average filter depends on the frictional mechanism, being larger for the viscous regime.
Scanning tunneling state recognition with multi-class neural network ensembles
Authors: Gordon O. , D’Hondt P. , Knijff L. , Freeney S. E. , Junqueira F. , Moriarty P. , Swart I.
Published: October 2019

One of the largest obstacles facing scanning probe microscopy is the constant need to correct flaws in the scanning probe in situ. This is currently a manual, time-consuming process that would benefit greatly from automation. Here, we introduce a convolutional neural network protocol that enables automated recognition of a variety of desirable and undesirable scanning tunneling tip states on both metal and nonmetal surfaces. By combining the best performing models into majority voting ensembles, we find that the desirable states of H:Si(100) can be distinguished with a mean precision of 0.89 and an average receiver-operator-characteristic curve area of 0.95. More generally, high and low-quality tips can be distinguished with a mean precision of 0.96 and near perfect area-under-curve of 0.98. With trivial modifications, we also successfully automatically identify undesirable, non-surface-specific states on surfaces of Au(111) and Cu(111). In these cases, we find mean precisions of 0.95 and 0.75 and area-under-curves of 0.98 and 0.94, respectively. Provided that training data are available, these ensembles therefore enable fully autonomous scanning tunneling state recognition for a wide range of typical scanning conditions.
Dust acoustic solitons in an opposite polarity dusty plasma in the presence of generalized polarization force
Authors: Khaled M. A. H. , Shukri M. A. , Hager Y. A. A.
Published: October 2019

Propagation characteristics of dust acoustic (DA) solitons in an opposite polarity dusty plasma medium containing inertial positive and negative dust grains and inertialess ions and electrons following Maxwellian distribution have been theoretically investigated by taking the effect of generalized polarization force into consideration. By using the reductive perturbation method, the Korteweg–de Vries equation that governs the nonlinear dust acoustic waves has been derived. It has been found that rarefactive and compressive solitons (solitons associated with negative and positive potentials) propagate in such a dusty plasma medium. The dependence of soliton characteristics on the system parameters has been discussed. It is observed that the basic properties of the DA solitons are significantly modified by the effects of generalized polarization force, ion-to-electron temperature ratio, and positive dust component. The findings of this investigation may be used in understanding the wave propagation in space and laboratory plasmas in which dust of opposite polarity coexists under the polarization force.
A single-laser alternating-frequency magneto-optical trap
Authors: Wiegand B. , Leykauf B. , Döringshoff K. , Gupta Y. D. , Peters A. , Krutzik M.
Published: October 2019

In this paper, we present a technique for magneto-optical cooling and trapping of neutral atoms using a single laser. The alternating-frequency magneto-optical trap (AF-MOT) uses an agile light source that sequentially switches between cooling and repumping transition frequencies by tuning the injection current of the laser diode. We report on the experimental demonstration of such a system for 87Rb and 85Rb based on a microintegrated extended cavity diode laser performing laser frequency jumps of up to 6.6 GHz with a tuning time in the microsecond regime and a repetition rate of up to 7.6 kHz. For that, a combination of a feed-forward for coarse frequency control and a feedback for precise locking was used. We discuss the results of the AF-MOT characterization in terms of atom numbers and cloud temperature for different operation parameters.
A sliding window-based algorithm for faster transformation of time series into complex networks
Authors: Carmona-Cabezas Rafael , Gómez-Gómez Javier , Gutiérrez de Ravé Eduardo , Jiménez-Hornero Francisco José
Published: October 2019

A new alternative method to approximate the Visibility Graph (VG) of a time series has been introduced here. It exploits the fact that most of the nodes in the resulting network are not connected to those that are far away from them. This means that the adjacency matrix is almost empty, and its nonzero values are close to the main diagonal. This new method is called Sliding Visibility Graph (SVG). Numerical tests have been performed for several time series, showing a time efficiency that scales linearly with the size of the series [O(N)], in contrast to the original VG that does so quadratically [O(N2)]. This fact is noticeably convenient when dealing with very large time series. The results obtained from the SVG of the studied time series have been compared to the exact values of the original VG. As expected, the SVG outcomes converge very rapidly to the desired ones, especially for random and stochastic series. Also, this method can be extended to the analysis of time series that evolve in real time, since it does not require the entire dataset to perform the analysis but a shorter segment of it. The length segment can remain constant, making possible a simple analysis as the series evolves in time.
The dynamics of geometric PDEs: Surface evolution equations and a comparison with their small gradient approximations
Authors: Kabelitz C. , Linz S. J.
Published: October 2019

Apart from three-dimensional continuum and discrete models, the evolution of surfaces is usually described by spatially two-dimensional partial differential equations (PDEs). These models are often derived from or at least motivated by small gradient approximations, but the studied surfaces do not fulfill this requirement in all cases. We will investigate how to overcome the small gradient approximation by using geometric PDEs. Therefore, we will introduce a method to simulate the evolution of surfaces with respect to local geometric properties. In contrast to traditional PDEs, this method does not depend on the parametrization of the surface. It will not only allow us to simulate surface evolution on flat geometries but also on more complex shaped objects. For small gradients, the studies of simple model equations show similar results compared to the related PDEs. For large gradients the results differ fundamentally. Hence, the small gradient approximation should only be applied in cases where large gradients does not appear. Specifically, we exemplify this using various equations including the (damped) Kuramoto-Sivashinsky equation, which is used as a minimal model for low-energetic erosion and deposition processes, and its geometric PDE counterpart.
Modification of classical electron transport due to collisions between electrons and fast ions
Authors: Appelbe B. , Sherlock M. , El-Amiri O. , Walsh C. , Chittenden J.
Published: October 2019

A Fokker-Planck model for the interaction of fast ions with the thermal electrons in a quasineutral plasma is developed. When the fast ion population has a net flux (i.e., the distribution of fast ions is anisotropic in velocity space), the electron distribution function is perturbed from Maxwellian by collisions with the fast ions, even if the fast ion density is orders of magnitude smaller than the electron density. The Fokker-Planck model is used to derive classical electron transport equations (a generalized Ohm's law and a heat flow equation) that include the effects of the electron-fast ion collisions. It is found that these collisions result in a collisionally induced current term in the transport equations which can be significant. The new transport equations are analyzed in the context of a number of scenarios including α particle heating in inertial confinement fusion and magnetoinertial fusion plasmas as well as ion beam heating of dense plasmas.
Computational study of instability and fill tube mitigation strategies for double shell implosions
Authors: Haines Brian M. , Daughton W. S. , Loomis E. N. , Merritt E. C. , Montgomery D. S. , Sauppe J. P. , Kline J. L.
Published: October 2019

Double shell capsules are an attractive alternative scheme for achieving robust alpha-heating at the National Ignition Facility due to their low convergence ratio and low predicted temperature for achieving volume ignition. Nevertheless, simulations suggest that double shell targets are more susceptible to the fill tube, used to fill the inner shell with liquid DT, than typical single-shell ignition capsule designs, due to the higher density gradient between the shell and the fill tube hole, a lower outer shell velocity, which prevents the implosion from catching up to the initial fill tube jet, and the absence of a rebounding shock through the foam to slow this jet. Double shells are also highly susceptible to the Rayleigh-Taylor instability at both interfaces with the high density inner shell. Combined, these effects are predicted by radiation-hydrodynamics simulations to reduce fuel confinement and temperature, resulting in reduced performance by a factor of ≈20–45, depending on design details, compared to idealized one-dimensional (1D) simulations. We discuss a mitigation strategy for both the interfacial instabilities and the fill tube that is predicted by simulations to decrease the yield degradation to a factor of ≈4. The mitigation strategy involves a modification of the capsule geometry as well as the use of a multishock pulse shape. The multishock pulse is required for the fill tube mitigation strategy and has the added benefit of stabilizing perturbations at the foam/pusher interface without decreasing 1D yield. In order to experimentally verify these predictions, we discuss the potential use of a hydrogrowth radiography platform that could be applied to test the proposed mitigation strategies.
Improved linearized model collision operator for the highly collisional regime
Authors: Sugama H. , Matsuoka S. , Satake S. , Nunami M. , Watanabe T.-H.
Published: October 2019

The linearized model collision operator for multiple species plasmas given by Sugama et al. [Phys. Plasmas 16, 112503 (2009)] is improved to be properly applicable up to the highly collisional regime. The improved linearized model operator retains the conservation laws of particles, momentum, and energy, and it reproduces the same friction-flow relations as derived by the linearized Landau operator so that this model can be used to correctly evaluate neoclassical transport fluxes in all collisionality regimes. The adjointness relations and Boltzmann's H-theorem are exactly satisfied by the improved operator except in the case of collisions between unlike particle species with unequal temperatures where these relations and H-theorem still hold approximately because there is a large difference between the masses of the two species with significantly different temperatures. Even in the unequal-temperature case, the improved operator can also be modified so as to exactly satisfy the adjointness relations, while it causes the values of the friction coefficients to deviate from those given by the Landau operator. In addition, for application to gyrokinetic simulations of turbulent transport, the improved operator is transformed into the gyrophase-averaged form by keeping the finite gyroradius effect.
Femtosecond bond breaking and charge dynamics in ultracharged amino acids
Authors: Grånäs Oscar , Timneanu Nicusor , Eliah Dawod Ibrahim , Ragazzon Davide , Trygg Sebastian , Souvatzis Petros , Edvinsson Tomas , Caleman Carl
Published: October 2019

Historically, structure determination of nanocrystals, proteins, and macromolecules required the growth of high-quality crystals sufficiently large to diffract X-rays efficiently while withstanding radiation damage. The development of the X-ray free-electron laser has opened the path toward high resolution single particle imaging, and the extreme intensity of the X-rays ensures that enough diffraction statistics are collected before the sample is destroyed by radiation damage. Still, recovery of the structure is a challenge, in part due to the partial fragmentation of the sample during the diffraction event. In this study, we use first-principles based methods to study the impact of radiation induced ionization of six amino acids on the reconstruction process. In particular, we study the fragmentation and charge rearrangement to elucidate the time scales involved and the characteristic fragments occurring.
Early detection of thermoacoustic combustion oscillations using a methodology combining statistical complexity and machine learning
Authors: Hachijo Takayoshi , Masuda Shinga , Kurosaka Takuya , Gotoda Hiroshi
Published: October 2019

We conduct an experimental study on early detection of thermoacoustic combustion oscillations using a method combining statistical complexity and machine learning, including the characterization of intermittent combustion oscillations. Abrupt switching from aperiodic small-amplitude oscillations to periodic large-amplitude oscillations and vice versa appears in pressure fluctuations. The dynamic behavior of aperiodic small-amplitude pressure fluctuations represents chaos. The complexity-entropy causality plane effectively captures the subtle changes in the combustion state during a transition to well-developed combustion oscillations. The feature space of the complexity-entropy causality plane, which is obtained by a support vector machine, has potential use for detecting a precursor of combustion oscillations.