bluuebunny/crossref_metadata_2025 huggingface dataset:
Tracheostomy demographics and outcomes among pediatric patients ages 18 years or younger—United States 2012
Authors: Sakai Mark , Kou Yann‐Fuu , Shah Gopi B. , Johnson Romaine F.
Published: November 2018

Objectives/Hypothesis

To estimate the number, demographics, and outcomes of pediatric patients who underwent tracheostomy in 2012 and to contrast those outcomes by age, race, and gender.

Study Design

Cross‐sectional study.

Methods

The 2012 Kids Inpatient Database was queried to identify tracheostomy patients using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) procedural codes 311, 3121, and 3129. All patients ≤18 years of age at the time of admission were included and categorized as neonates (≤28 days), infants (>28 days ≤1 year), toddler (1 to 3 years), children (4 to 12 years), adolescents (13 to 17 years), and adults (=18 years). We recorded age, gender, race, insurance status, and zip code of primary residence. We used these variables to contrast the following outcomes: length of stay, total charges, complications of care, and mortality using multiple regression analysis.

Results

An estimated 4,424 pediatric tracheostomies occurred during 2012. Fifty‐one percent of the patients were ≤3 years old, and 62% were male. Forty‐eight percentwere white followed by black (21%), Hispanic (20%), and Asian (3%). The median length of stay was 42 days, and the median total charges were $472,738. The complication rate was 29% and the mortality rate was 8.0%. The length of stay and total charges was predicted by age, with neonates having significantly longer hospitalizations. The complication rate was not associated with age, gender, or ethnicity. However, the mortality rate was associated with younger age.

Conclusions

Pediatric tracheostomies are associated with significant hospital utilizations, complications, and mortality. Increased risk of mortality is observed among neonates and infants. Continued study of tracheostomy outcomes among these subsets of the pediatric population are warranted.

Level of Evidence

4

Laryngoscope, 129:1706–1711, 2019
Interpretation of total phytoplankton and cyanobacteria fluorescence from cross‐calibrated fluorometers, including sensitivity to turbidity and colored dissolved organic matter
Authors: Cremella Bruno , Huot Yannick , Bonilla Sylvia
Published: November 2018

In vivo pigment fluorescence methods allow simple real‐time detection and quantification of freshwater algae and cyanobacteria. Available models are still limited to high‐cost fluorometers, validated for single instruments or individual water bodies, preventing data comparison between multiple instruments, and thus, restricting their use in large‐scale monitoring programs. Moreover, few models include corrections for optical interference (water turbidity and colored dissolved organic matter, CDOM). In this study, we developed simple models to predict phytoplankton and cyanobacterial chlorophyll a (Chl a) concentrations based on Chl a and C‐phycocyanin in vivo fluorescence, using multiple low‐cost handheld fluorometers. We aimed to: (1) fit models to mixed cyanobacterial and microalgal cultures; (2) cross‐calibrate nine fluorometers of the same brand and series; (3) correct the CDOM and turbidity effects; and (4) test the algorithms’ performance with natural samples. We achieved comparable results between nine instruments after the cross‐calibration, allowing their simultaneous use. We obtained algorithms for total and cyanobacterial Chl a estimation. We developed parametric corrections to remove CDOM and turbidity interferences in the algorithms. Five sampling sites (from a lake, a stream, and an estuary) were used to test the algorithms using eight cross‐calibrated fluorometers. The models showed their best performance after CDOM and turbidity corrections (total Chl a: R2 = 0.99, RMSE = 7.8 μg Chl a L−1; cyanobacterial Chl a: R2 = 0.98, RMSE = 9.8 μg Chl a L−1). In summary, our models can quantify total phytoplankton and cyanobacterial Chl a in real time with multiple low‐cost fluorometers, allowing its implementation in large‐scale monitoring programs.
A new analysis approach for T2 relaxometry myelin water quantification: Orthogonal Matching Pursuit
Authors: Drenthen Gerhard S. , Backes Walter H. , Aldenkamp Albert P. , Op ’t Veld Giel J. , Jansen Jacobus F. A.
Published: November 2018

Purpose

In vivo myelin quantification can provide valuable noninvasive information on neuronal maturation and development, as well as insights into neurological disorders. Multiexponential analysis of multiecho T2 relaxation is a powerful and widely applied method for the quantification of the myelin water fraction (MWF). In recent literature, the MWF is most commonly estimated using a regularized nonnegative least squares algorithm.

Methods

The orthogonal matching pursuit algorithm is proposed as an alternative method for the estimation of the MWF. The orthogonal matching pursuit is a greedy sparse reconstruction algorithm with a low computation complexity. For validation, both methods are compared to a ground truth using numerical simulations and a phantom model using comparable computation times. The numerical simulations were used to measure the theoretical errors, as well as the effects of varying the SNR, strength of the regularization, and resolution of the basis set. Additionally, a phantom model was used to estimate the performance of the 2 methods while including errors occurring due to the MR measurement. Lastly, 4 healthy subjects were scanned to evaluate the in vivo performance.

Results

The results in simulations and phantoms demonstrate that the MWFs determined with the orthogonal matching pursuit are 1.7 times more accurate as compared to the nonnegative least squares, with a comparable precision. The remaining bias of the MWF is shown to be related to the regularization of the nonnegative least squares algorithm and the Rician noise present in magnitude MR images.

Conclusion

The orthogonal matching pursuit algorithm provides a more accurate alternative for T2 relaxometry myelin water quantification.
Investigation of mechanical and abrasive wear behavior of blast furnace slag‐filled needle‐punched nonwoven viscose fabric epoxy hybrid composites
Authors: Patnaik Prabina Kumar , Swain Priyadarshi Tapas Ranjan , Biswas Sandhyarani
Published: November 2018

In this work, a new class of hybrid composites consisting of needle‐punched nonwoven viscose fabric reinforced epoxy filled with different weight proportions (0, 5, 10, and 15 wt%) of blast furnace slag (BFS) are prepared. The mechanical study of these composites indicated that hardness, impact strength are increased with increase in filler wt% whereas the properties like tensile, flexural and inter‐laminar shear strength are reduced beyond 10 wt% of filler loading. Abrasive wear behavior of these composites is investigated by slurry abrasion test rig (ASTM G105). The optimum parametric combination is determined for minimum wear rate and further validated through confirmation experiment as per Taguchi experimental design. Slurry abrasion test results revealed that wear resistance of viscose fabric/epoxy composites has been improved with the inclusion of BFS particulate fillers. The morphological study of abraded surfaces examined by scanning electron microscopy and the possible wear mechanisms responsible for wear are discussed. POLYM. COMPOS., 40:2335–2345, 2019. © 2018 Society of Plastics Engineers
Burning Characteristics of the HMX/CL‐20/AP/Polyvinyltetrazole Binder/Al Solid Propellants Loaded with Nanometals
Authors: Sergienko Alexey V. , Popenko Elena M. , Slyusarsky Konstantin V. , Larionov Kirill B. , Dzidziguri Ella L. , Kondratyeva Elena S. , Gromov Alexander A.
Published: November 2018

The paper investigated the effect of metal nanopowders additive on the combustion properties of HMX/CL‐20/AP/polyvinyltetrazole binder/Al propellants. Using thermal analysis, the authors described the effect of aluminum, boron, zinc, nickel, copper, and molybdenum and identified the combustion in a pressure range from 4 to 10 MPa with a pressure step of 1 MPa. No significant correlation between the oxidation properties of the n‐Me powders and the combustion properties of propellants was discovered. An addition of nanopowders caused an increase in the propellant burning rate by approximately 30 % for n‐Al, n‐B, n‐Ni, and n‐Mo independent from the pressure values. An addition of n‐Cu resulted in a burning rate increase by a factor of 4.9 due to coppers’ probable catalytic activity during interaction with nitroesters and cyclic nitramines in a solid phase. n‐Zn additive increased the propellant burning rate by factors 2.3 and 3.6 at 4 and 10 MPa, respectively, due to catalytic activity of zinc in a gaseous phase.
In‐water visual ship hull inspection using a hover‐capable underwater vehicle with stereo vision
Authors: Hong Seonghun , Chung Dongha , Kim Jinwhan , Kim Youngji , Kim Ayoung , Yoon Hyeon Kyu
Published: November 2018

Underwater visual inspection is an important task for checking the structural integrity and biofouling of the ship hull surface to improve the operational safety and efficiency of ships and floating vessels. This paper describes the development of an autonomous in‐water visual inspection system and its application to visual hull inspection of a full‐scale ship. The developed system includes a hardware vehicle platform and software algorithms for autonomous operation of the vehicle. The algorithms for vehicle autonomy consist of the guidance, navigation, and control algorithms for real‐time and onboard operation of the vehicle around the hull surface. The environmental perception of the developed system is mainly based on optical camera images, and various computer vision and optimization algorithms are used for vision‐based navigation and visual mapping. In particular, a stereo camera is installed on the underwater vehicle to estimate instantaneous surface normal vectors, which enables high‐precision navigation and robust visual mapping, not only on flat areas but also over moderately curved hull surface areas. The development process of the vehicle platform and the implemented algorithms are described. The results of the field experiment with a full‐scale ship in a real sea environment are presented to demonstrate the feasibility and practical performance of the developed system.
Nitrosyltechnetium(I) Complexes with 2‐(Diphenylphosphanyl)aniline
Authors: Ackermann Janine , Noufele Christelle Nijki , Hagenbach Adelheid , Abram Ulrich
Published: November 2018

[TcI(NO)Cl(H2L1)2]+ cations (H2L1 = 2‐(diphenylphosphanyl)aniline) are formed during reactions of H2L1 with (NBu4)[Tc(NO)Cl4(MeOH)] or (NH4)TcO4/HCl/NH2OH mixtures. Different isomers were isolated depending on the counterions and solvents used. The technetium(I) complexes cis‐NO,Cl,trans‐P,P‐[TcI(NO)Cl(H2L1)2]Cl, trans‐NO,Cl,cis‐P,P‐[TcI(NO)Cl(H2L1)2]2(TcCl6), and trans‐NO,Cl,trans‐P,P‐[TcI(NO)Cl(H2L1)2](PF6) were isolated in crystalline form and studied by spectroscopic methods and X‐ray crystallography. DFT calculations show that there are only minor energy differences between the three isomers and the formation of the individual compounds is most probably strongly influenced by interactions with solvents and counterions.
Substituted 2,2′‐Bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyl Complexes of Zinc
Authors: Al‐Shboul Tareq M. A. , Ziemann Steffen , Görls Helmar , Krieck Sven , Westerhausen Matthias
Published: November 2018

The condensation reaction of 2,2′‐diamino‐4,4′‐dimethyl‐6,6'‐dibromo‐1,1′‐biphenyl with 2‐hydroxybenzaldehyde as well as 5‐methoxy‐, 4‐methoxy‐, and 3‐methoxy‐2‐hydroxybenzaldehyde yields 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyl (1a) as well as the 5‐, 4‐, and 3‐methoxy‐substituted derivatives1b,1c, and1d, respectively. Deprotonation of substituted 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls with diethylzinc yields the corresponding substituted zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls (2) or zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyls (3). Recrystallization from a mixture of CH2Cl2and methanol can lead to the formation of methanol adducts. The methanol ligands can either bind as Lewis base to the central zinc atom or as Lewis acid via a weak O–H···O hydrogen bridge to a phenoxide moiety. Methanol‐free complexes precipitate as dimers with central Zn2O2rings.
Handling handles. Part II. Stratification and data analysis
Authors: Bargheer T. , Caetano J. , Fleury T. , Komatsu S. , Vieira P.
Published: November 2018

Abstract

In a previous work [1], we proposed an integrability setup for computing nonplanar corrections to correlation functions in

$$ \mathcal{N}=4 $$

N
=
4

super-Yang-Mills theory at any value of the coupling constant. The procedure consists of drawing all possible tree-level graphs on a Riemann surface of given genus, completing each graph to a triangulation, inserting a hexagon form factor into each face, and summing over a complete set of states on each edge of the triangulation. The summation over graphs can be interpreted as a quantization of the string moduli space integration. The quantization requires a careful treatment of the moduli space boundaries, which is realized by subtracting degenerate Riemann surfaces; this procedure is called stratification. In this work, we precisely formulate our proposal and perform several perturbative checks. These checks require hitherto unknown multi-particle mirror contributions at one loop, which we also compute.
Bipartite field theories and D-brane instantons
Authors: Franco Sebastián , García-Valdecasas Eduardo , Uranga Angel M.
Published: November 2018

Abstract

We study D-brane instantons in systems of D3-branes at toric CY 3-fold singularities. The instanton effect can be described as a backreaction modifying the geometry of the mirror configuration, in which the breaking of U(1) symmetries by the instanton translates into the recombination of gauge D-branes, which also directly generates the instanton-induced charged field theory operator. In this paper we describe the D-brane instanton backreaction in terms of a combinatorial operation in the bipartite dimer diagram of the original theory. Interestingly, the resulting theory is a general Bipartite Field Theory (BFT), defined by a bipartite graph tiling a general (possibly higher-genus) Riemann surface. This provides the first string theory realization of such general BFTs. We study the general properties of the resulting theories, including the construction of the higher-dimensional toric diagrams and the interplay between backreaction and Seiberg duality. In cases where the non-perturbative effects relate to complex deformations, we show that the procedure reproduces and explains earlier existing combinatorial recipes. The combinatorial operation and its properties generalize to an operation on the class of general BFTs, even including boundaries, relating BFTs defined on Riemann surfaces of different genus.
Updated European Consensus Statement on diagnosis and treatment of adult ADHD
Authors: Kooij J.J.S. , Bijlenga D. , Salerno L. , Jaeschke R. , Bitter I. , Balázs J. , Thome J. , Dom G. , Kasper S. , Nunes Filipe C. , Stes S. , Mohr P. , Leppämäki S. , Casas M. , Bobes J. , Mccarthy J.M. , Richarte V. , Kjems Philipsen A. , Pehlivanidis A. , Niemela A. , Styr B. , Semerci B. , Bolea-Alamanac B. , Edvinsson D. , Baeyens D. , Wynchank D. , Sobanski E. , Philipsen A. , McNicholas F. , Caci H. , Mihailescu I. , Manor I. , Dobrescu I. , Saito T. , Krause J. , Fayyad J. , Ramos-Quiroga J.A. , Foeken K. , Rad F. , Adamou M. , Ohlmeier M. , Fitzgerald M. , Gill M. , Lensing M. , Motavalli Mukaddes N. , Brudkiewicz P. , Gustafsson P. , Tani P. , Oswald P. , Carpentier P.J. , De Rossi P. , Delorme R. , Markovska Simoska S. , Pallanti S. , Young S. , Bejerot S. , Lehtonen T. , Kustow J. , Müller-Sedgwick U. , Hirvikoski T. , Pironti V. , Ginsberg Y. , Félegyházy Z. , Garcia-Portilla M.P. , Asherson P.
Published: November 2018

Background Attention-deficit/hyperactivity disorder (ADHD) is among the most common psychiatric disorders of childhood that often persists into adulthood and old age. Yet ADHD is currently underdiagnosed and undertreated in many European countries, leading to chronicity of symptoms and impairment, due to lack of, or ineffective treatment, and higher costs of illness.

Methods The European Network Adult ADHD and the Section for Neurodevelopmental Disorders Across the Lifespan (NDAL) of the European Psychiatric Association (EPA), aim to increase awareness and knowledge of adult ADHD in and outside Europe. This Updated European Consensus Statement aims to support clinicians with research evidence and clinical experience from 63 experts of European and other countries in which ADHD in adults is recognized and treated.

Results Besides reviewing the latest research on prevalence, persistence, genetics and neurobiology of ADHD, three major questions are addressed: (1) What is the clinical picture of ADHD in adults? (2) How should ADHD be properly diagnosed in adults? (3) How should adult ADHDbe effectively treated?

Conclusions ADHD often presents as a lifelong impairing condition. The stigma surrounding ADHD, mainly due to lack of knowledge, increases the suffering of patients. Education on the lifespan perspective, diagnostic assessment, and treatment of ADHD must increase for students of general and mental health, and for psychiatry professionals. Instruments for screening and diagnosis of ADHD in adults are available, as are effective evidence-based treatments for ADHD and its negative outcomes. More research is needed on gender differences, and in older adults with ADHD.
Recent crustal uplift of Precambrian cratons: key patterns and possible mechanisms
Authors: Artyushkov E.V. , Korikovsky S.P. , Massonne H.-J. , Chekhovich P.A.
Published: November 2018

Precambrian cratons cover about 70% of the total continental area. According to a large volume of geomorphological, geological, paleontological, and other data for the Pliocene and Pleistocene, these cratons have experienced a crustal uplift from 100–200 m to 1000–1500 m, commonly called the recent or Neotectonic uplift. Shortening of the Precambrian crust terminated half a billion years ago or earlier, and its uplift could not have been produced by this mechanism. According to the main models of dynamic topography in the mantle, the distribution of displacements at the surface is quite different from that of the Neotectonic movements. According to seismic data, there is no magmatic underplating beneath most of the Precambrian cratons. In most of cratonic areas, the mantle lithosphere is very thick, which makes its recent delamination unlikely. Asthenospheric replacement of the lower part of the mantle lithosphere beneath the Precambrian cratons might have produced only a minor part of their Neotectonic uplifts. Since the above mechanisms cannot explain this phenomenon, the rock expansion in the crustal layer is supposed to be the main cause of the recent uplift of Precambrian cratons. This is supported by the strong lateral nonuniformity of the uplift, which indicates that expansion of rocks took place at a shallow depth. Expansion might have occurred in crustal rocks that emerged from the lower crust into the middle crust with lower pressure and temperature after the denudation of a thick layer of surface rocks. In the dry state, these rocks can remain metastable for a long time. However, rapid metamorphism accompanied by expansion of rocks can be caused by infiltration of hydrous fluids from the mantle. Analysis of phase diagrams for common crustal rocks demonstrates that this mechanism can explain the recent crustal uplift of Precambrian cratons.
The sum of component concentrations as a quality indicator in X-ray electron probe microanalysis of minerals
Authors: Lavrent’ev Yu.G. , Usova L.V.
Published: November 2018

X-ray electron probe microanalysis is a complete mineral analysis technique. Therefore, the sum of obtained concentrations can be used as an indicator of the quality of analysis. There are two kinds of errors of the sum of concentrations. The first is related to the deviation of the sum from the basic value and can be called a difference error. The second is the scattering of results around the mean value and can be called an averaging error. The difference error characterizes the reproducibility of the measurements and equals 0.41% at the current precision level. The averaging error characterizes the repeatability of the measurements and equals 0.23%. The difference error can be used as a quality indicator directly during analysis, while the averaging error can be used after analysis of a batch of specimens. According to the modified three-sigma rule, the acceptable sum values of separate analyses are in the range 98.8–100.8%. This range is obviously valid only for an ideal model with a basic sum value of 100%. In real analyses, the basic value deviates from 100% because of the presence of elements which are not detected in the analysis and elements with a variable valence. According to the three-sigma rule, the acceptable scattering of the sum of concentrations around the average value is ±0.7%.
Foundations of petroleum prediction based on the activation of geochemical processes by direct current
Authors: Shigaev V.Yu.
Published: November 2018

Petroleum prediction in local objects and the applicability of geologic environment parameters in this regard are considered. The proposed guidelines for petroleum potential prediction are based on the analysis of the distribution of typomorphic epigenetic multivalent elements loosely fixed in rocks before and after electric current treatment. The advantage of geoelectrochemical methods providing data on the chemical composition of above-productive deposits is demonstrated.
Identification and isotropy characterization of deformed random fields through excursion sets
Authors: Fournier Julie
Published: November 2018

A deterministic application θ:ℝ2→ℝ2 deforms bijectively and regularly the plane and allows the construction of a deformed random field X∘θ:ℝ2→ℝ from a regular, stationary, and isotropic random field X:ℝ2→ℝ. The deformed field X∘θ is, in general, not isotropic (and not even stationary), however, we provide an explicit characterization of the deformations θ that preserve the isotropy. Further assuming that X is Gaussian, we introduce a weak form of isotropy of the field X∘θ, defined by an invariance property of the mean Euler characteristic of some of its excursion sets. We prove that deformed fields satisfying this property are strictly isotropic. In addition, we are able to identify θ, assuming that the mean Euler characteristic of excursion sets of X∘θ over some basic domain is known.
The role of cooperation in spatially explicit economical systems
Authors: Lanchier N. , Reed S.
Published: November 2018

In this paper we are concerned with a model in econophysics, the subfield of statistical physics that applies concepts from traditional physics to economics. Our model is an example of an interacting particle system with disorder, meaning that some of the transition rates are not identical but rather drawn from a fixed distribution. Economical agents are represented by the vertices of a connected graph and are characterized by the number of coins they possess. Agents independently spend one coin at rate one for their basic need, earn one coin at a rate chosen independently from a distribution ϕ, and exchange money at rate µ with one of their nearest neighbors, with the richest neighbor giving one coin to the other neighbor. If an agent needs to spend one coin when his/her fortune is at 0, he/she dies, i.e. the corresponding vertex is removed from the graph. Our first results focus on the two extreme cases of lack of cooperation µ=0 and perfect cooperation µ = ∞ for finite connected graphs. These results suggest that, when overall the agents earn more than they spend, cooperation is beneficial for the survival of the population, whereas when overall the agents earn less than they spend, cooperation becomes detrimental. We also study the infinite one-dimensional system. In this case, when the agents earn less than they spend on average, the density of agents that die eventually is bounded from below by a positive constant that does not depend on the initial number of coins per agent or the level of cooperation.
Compound Poisson approximation of subgraph counts in stochastic block models with multiple edges
Authors: Coulson Matthew , Gaunt Robert E. , Reinert Gesine
Published: November 2018

We use the Stein‒Chen method to obtain compound Poisson approximations for the distribution of the number of subgraphs in a generalised stochastic block model which are isomorphic to some fixed graph. This model generalises the classical stochastic block model to allow for the possibility of multiple edges between vertices. We treat the case that the fixed graph is a simple graph and that it has multiple edges. The former results apply when the fixed graph is a member of the class of strictly balanced graphs and the latter results apply to a suitable generalisation of this class to graphs with multiple edges. We also consider a further generalisation of the model to pseudo-graphs, which may include self-loops as well as multiple edges, and establish a parameter regime in the multiple edge stochastic block model in which Poisson approximations are valid. The results are applied to obtain Poisson and compound Poisson approximations (in different regimes) for subgraph counts in the Poisson stochastic block model and degree corrected stochastic block model of Karrer and Newman (2011).
Importance sampling of heavy-tailed iterated random functions
Authors: Chen Bohan , Rhee Chang-Han , Zwart Bert
Published: November 2018

We consider the stationary solutionZof the Markov chain {Zn}n∈ℕdefined byZn+1=ψn+1(Zn), where {ψn}n∈ℕis a sequence of independent and identically distributed random Lipschitz functions. We estimate the probability of the event {Z>x} whenxis large, and develop a state-dependent importance sampling estimator under a set of assumptions on ψnsuch that, for largex, the event {Z>x} is governed by a single large jump. Under natural conditions, we show that our estimator is strongly efficient. Special attention is paid to a class of perpetuities with heavy tails.
Status and development of high-power laser facilities at the NLHPLP
Authors: Zhu Jianqiang , Zhu Jian , Li Xuechun , Zhu Baoqiang , Ma Weixin , Lu Xingqiang , Fan Wei , Liu Zhigang , Zhou Shenlei , Xu Guang , Zhang Guowen , Xie Xinglong , Yang Lin , Wang Jiangfeng , Ouyang Xiaoping , Wang Li , Li Dawei , Yang Pengqian , Fan Quantang , Sun Mingying , Liu Chong , Liu Dean , Zhang Yanli , Tao Hua , Sun Meizhi , Zhu Ping , Wang Bingyan , Jiao Zhaoyang , Ren Lei , Liu Daizhong , Jiao Xiang , Huang Hongbiao , Lin Zunqi
Published: November 2018

In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.
Loss mechanism of all-fiber cascaded side pumping combiner
Authors: Lei Chengmin , Chen Zilun , Gu Yanran , Xiao Hu , Hou Jing
Published: November 2018

Compared with end pumping fiber combiner, one of the advantages for side pumping combiner is the unlimited pumping points, which means multi-point or cascaded side pumping can be realized. However, the loss mechanism of the cascaded structure is rarely discussed. In this paper, we present the numerical and experimental investigation about the loss mechanism of a two-stage-cascaded side pumping combiner based on tapered-fused technique. The influence of loss mechanism on the coupling efficiency and thermal load of the fiber coating is analyzed according to simulations and experiments with different tapering ratios for the first stage. Based on the analysis, a cascaded component with total pump coupling efficiency of 96.4% handling a pump power of 1088 W is achieved by employing 1018 nm fiber laser as the pump source. Future work to further improve the performance of a cascaded side pumping combiner is discussed and prospected.
High power all-fiberized and narrow-bandwidth MOPA system by tandem pumping strategy for thermally induced mode instability suppression
Authors: Ma Pengfei , Xiao Hu , Meng Daren , Liu Wei , Tao Rumao , Leng Jinyong , Ma Yanxing , Su Rongtao , Zhou Pu , Liu Zejin
Published: November 2018

An all-fiberized and narrow-bandwidth master oscillator power amplification (MOPA) system with record output power of 4 kW level and slope efficiency of 78% is demonstrated. Tandem pumping strategy is tentatively introduced into the narrow-bandwidth MOPA system for thermally induced mode instability (TMI) suppression. The stimulated Brillouin scattering (SBS) effect is balanced by simply using one-stage phase modulation technique. With different phase modulation signals, SBS limited output powers of 336 W, 1.2 kW and 3.94 kW are respectively achieved with spectral bandwidths accounting for 90% power of ${\sim}$0.025, 0.17 and ${\sim}$0.89 nm. Compared with our previous 976 nm pumping system, TMI threshold is overall boosted to be ${>}$5 times in which tandem pumping increases the TMI threshold of ${>}$3 times. The beam quality ($M^{2}$ factor) of the output laser is well within 1.5 below the TMI threshold while it is ultimately saturated to be 1.86 with the influence of TMI at maximal output power. Except for SBS and TMI, stimulated Raman scattering (SRS) effect will be another challenge for further power scaling. In such a high power MOPA system, multi-detrimental effects (SBS, SRS and TMI) will coexist and may be mutual-coupled, which could provide a well platform for further comprehensively investigating and optimizing the high power, narrow-bandwidth fiber amplifiers.
How much market making does a market need?
Authors: Peržina Vít , Swart Jan M.
Published: November 2018

We consider a simple model for the evolution of a limit order book in which limit orders of unit size arrive according to independent Poisson processes. The frequencies of buy limit orders below a given price level, respectively sell limit orders above a given level, are described by fixed demand and supply functions. Buy (respectively, sell) limit orders that arrive above (respectively, below) the current ask (respectively, bid) price are converted into market orders. There is no cancellation of limit orders. This model has been independently reinvented by several authors, including Stigler (1964), and Luckock (2003), who calculated the equilibrium distribution of the bid and ask prices. We extend the model by introducing market makers that simultaneously place both a buy and sell limit order at the current bid and ask price. We show that introducing market makers reduces the spread, which in the original model was unrealistically large. In particular, we calculate the exact rate at which market makers need to place orders in order to close the spread completely. If this rate is exceeded, we show that the price settles at a random level that, in general, does not correspond to the Walrasian equilibrium price.
Reliability modeling of coherent systems with shared components based on sequential order statistics
Authors: Ashrafi S. , Zarezadeh S. , Asadi M.
Published: November 2018

In this paper we are concerned with the reliability properties of two coherent systems having shared components. We assume that the components of the systems are two overlapping subsets of a set of n components with lifetimes X1,...,Xn. Further, we assume that the components of the systems fail according to the model of sequential order statistics (which is equivalent, under some mild conditions, to the failure model corresponding to a nonhomogeneous pure-birth process). The joint reliability function of the system lifetimes is expressed as a mixture of the joint reliability functions of the sequential order statistics, where the mixing probabilities are the bivariate signature matrix associated to the structures of systems. We investigate some stochastic orderings and dependency properties of the system lifetimes. We also study conditions under which the joint reliability function of systems with shared components of order m can be equivalently written as the joint reliability function of systems of order n (n>m). In order to illustrate the results, we provide several examples.
Frog models on trees through renewal theory
Authors: Gallo Sandro , Rodriguez Pablo M.
Published: November 2018

We study a class of growing systems of random walks on regular trees, known as frog models with geometric lifetime in the literature. With the help of results from renewal theory, we derive new bounds for their critical parameters. Our approach also improves the existing bounds for the critical parameter of a percolation model on trees known as cone percolation.
Implications of radiocarbon ages of organic and inorganic carbon in coastal lakes in Florida for establishing a reliable chronology for sediment-based paleoclimate reconstruction
Authors: Wang Yang , Das Oindrila , Xu Xiaomei , Liu Jin , Jahan Shakura , Means Guy H. , Donoghue Joseph , Jiang Shijun
Published: November 2018

Coastal lake sediments are valuable paleoclimate archives provided that they can be accurately dated. Here, we report radiocarbon ages of bulk sediment organic matter (OM), plants, shells, particulate OM, and dissolved OM from coastal lakes in Florida. Bulk sediment OM yielded ages that are consistently older than contemporaneous plants and shells, indicating significant radiocarbon deficiencies in sedimentary OM in these lakes. The data show that the OM radiocarbon deficiency varies over time and with location, making it impossible to determine a proper correction factor for radiocarbon ages of bulk sediments from these lakes. As a result, we consider ages obtained from bulk sediment OM from these lakes unreliable. The age reversals in bulk sediment OM observed in the sediment cores are likely caused by rapid increases in erosion and sedimentation resulting from large storm events. The data also show that sedimentation rate can vary considerably within a given lake, implying that an age-depth model established for one core cannot be directly applied to other cores despite their close proximity. Analyses of shells from one of the lakes suggest that fresh/brackish-water shells may serve as a good substrate for radiocarbon dating owing to a small reservoir effect on inorganic carbon.
Institutional Pressures and Organizational Identity: The Case of Deutsche Werkstätten Hellerau in the GDR and Beyond, 1945–1996
Authors: Schreiter Katrin , Ravasi Davide
Published: November 2018

This article explores the case of Deutsche Werkstätten Hellerau (DWH)—a furniture and interior manufacturer founded in 1898—through state socialism after 1945 and reprivatization in the 1990s. Our analysis suggests that the firm's survival through multiple systemic disruptions was partly due to the preservation of a unique identity despite heavy institutional pressures for conformity. DWH adopted a “mixed conformity” strategy that attempted to pitch multiple concerns (cultural-aesthetic, ideological, economic) of political authorities against one another to buffer sociopolitical pressures, thus ultimately conforming to some (identity-consistent) demands, while violating other (identity-threatening) ones. This allowed DWH to successfully navigate tensions between sociopolitical expectations and the need to preserve a collective sense of distinctiveness and continuity over time.
Rigidity of Ext and Tor with Coefficients in Residue Fields of a Commutative Noetherian Ring
Authors: Christensen Lars Winther , Iyengar Srikanth B. , Marley Thomas
Published: November 2018

Let 𝔭 be a prime ideal in a commutative noetherian ringR. It is proved that if anR-moduleMsatisfies${\rm Tor}_n^R $(k(𝔭),M) = 0 for somen⩾R𝔭, wherek(𝔭) is the residue field at 𝔭, then${\rm Tor}_i^R $(k(𝔭),M) = 0 holds for alli⩾n. Similar rigidity results concerning${\rm Tor}_R^{\ast} $(k(𝔭),M) are proved, and applications to the theory of homological dimensions are explored.
A Modular André–Oort Statement with Derivatives
Authors: Spence Haden
Published: November 2018

In unpublished notes, Pila discussed some theory surrounding the modular function j and its derivatives. A focal point of these notes was the statement of two conjectures regarding j, j′ and j″: a Zilber–Pink-type statement incorporating j, j′ and j″, which was an extension of an apparently weaker conjecture of André–Oort type. In this paper, I first cover some background regarding j, j′ and j″, mostly covering the work already done by Pila. Then I use a seemingly novel adaptation of the o-minimal Pila–Zannier strategy to prove a weakened version of Pila's ‘Modular André–Oort with Derivatives’ conjecture. Under the assumption of a certain number-theoretic conjecture, the central theorem of the paper implies Pila's conjecture in full generality, as well as a more precise statement along the same lines.
Assouad Dimension of Random Processes
Authors: Howroyd Douglas C. , Yu Han
Published: November 2018

In this paper we study the Assouad dimension of graphs of certain Lévy processes and functions defined by stochastic integrals. We do this by introducing a convenient condition which guarantees a graph to have full Assouad dimension and then show that graphs of our studied processes satisfy this condition.
The potential use of probiotic and beneficial bacteria in the Brazilian dairy industry
Authors: Colombo Monique , Todorov Svetoslav Dimitrov , Eller Monique , Nero Luís Augusto
Published: November 2018

Scientific studies demonstrate the importance of intestinal microbiota to human health and how probiotic microorganisms can positively affect health when administered regularly and in adequate amounts. Probiotic bacteria can be part of fermented products and their functional importance is associated mainly with their metabolism. They are thought to benefit individuals to maintain their health and also to strengthen resistance against various types of diseases. The acceptance of probiotic cultures and products by consumers increased when these bacteria were marketed as natural cultures that help in digestion and health. Considering this, the food industry has an increasing demand for new candidates as probiotic cultures, and the dairy industry has a particular interest for fermented milks and other dairy products, since these are the most common food vehicles for probiotic cultures. Therefore, the dairy industries are increasingly seeking to improve their products with these beneficial bacteria. However, the legal peculiarities and excess of control agencies in Brazil makes the registration of these products and the collection of data very complex. Prospective analysis suggests that probiotic foods have the potential to effect a considerable expansion of the dairy industry, allowing the dairy sector to grow and for these products to be increasingly sought by consumers globally. For this, not only actions on research and innovation are necessary, but also official clarifications on the claims for considerations of microbiological security and functionality of these products. This review aims to elucidate important probiotic research regarding the isolation and characterization of beneficial cultures in Brazil, and to demonstrate the relevance of the dairy chain as a potential source of novel cultures for the development of new probiotic products to expand the Brazilian dairy industry.
Assessing risk of neurodevelopmental disorders after birth with oxytocin: a systematic review and meta-analysis
Authors: Lønfeldt Nicole N. , Verhulst Frank C. , Strandberg-Larsen Katrine , Plessen Kerstin J. , Lebowitz Eli R.
Published: November 2018

Experts have raised concerns that oxytocin for labor induction and augmentation may have detrimental effects on the neurodevelopment of children. To investigate whether there is the reason for concern, we reviewed and evaluated the available evidence by searching databases with no language or date restrictions up to 9 September 2018. We included English-language studies reporting results on the association between perinatal oxytocin exposure and any cognitive impairment, psychiatric symptoms or disorders in childhood. We assessed the quality of studies using the Newcastle–Ottawa Quality Assessment Scales. Independent risk estimates were pooled using random-effects meta-analyses when at least two independent datasets provided data on the same symptom or disorder. Otherwise, we provided narrative summaries. Two studies examined cognitive impairment, one examined problem behavior, three examined attention-deficit/hyperactivity disorder (ADHD) and seven focused on autism spectrum disorders (ASD). We provided narrative summaries of the studies on cognitive impairment. For ADHD, the pooled risk estimate was 1.17; 95% confidence interval (CI) 0.77–1.78, based on a pooled sample size of 5 47 278 offspring. For ASD, the pooled risk estimate was 1.10; 95% CI 1.04–1.17, based on 8 87 470 offspring. Conclusions that perinatal oxytocin increases the risks of neurodevelopmental problems are premature. Observational studies of low to high quality comprise the evidence-base, and confounding, especially by the genetic or environmental vulnerability, remains an issue. Current evidence is insufficient to justify modifying obstetric guidelines for the use of oxytocin, which state that it should only be used when clinically indicated.
Diplomacy in drag and queer IR art: Reflections on the performance, ‘Sipping Toffee with Hamas in Brussels’
Authors: Charrett Catherine
Published: November 2018

This article presents drag performance as a queer method of critique in the field of IR, which contributes to a longstanding move in IR to engage with aesthetics, and a more recent move to engage with performance art. The article discusses the author’s making of a performance piece that revisited the EU’s response to Hamas’s success in the 2006 Palestinian legislative elections. Soft, camp, feminine, and childlike voices; a female body in men’s clothing; and the translocation of bodies in spaces are used in the performance piece to disrupt the coherency of normalised diplomacy. Queer IR theory emphasises the imperative to dismantle logics of normality that prevent creativity in response to political issues. Performative drag practices disrupt anxious attachments to a ritualised discourse of strategic interests that shapes political initiatives. This article comments on other drag moments in politics, such as the anxiety around Jeremy Corbyn’s dress, Barack Obama’s anger translator, and Janelle Monáe’s androgynous articulation of community. The form that research dissemination takes implicates the kind of knowledge that is produced. This article reviews three methodological provocations of drag, an alternative departure point of the ‘what if’, performing a politics of refusal, and a Brechtian technique of estrangement.
TESTING THE ORDER OF FRACTIONAL INTEGRATION OF A TIME SERIES IN THE POSSIBLE PRESENCE OF A TREND BREAK AT AN UNKNOWN POINT
Authors: Iacone Fabrizio , Leybourne Stephen J. , Taylor A.M. Robert
Published: November 2018

We develop a test, based on the Lagrange multiplier [LM] testing principle, for the value of the long memory parameter of a univariate time series that is composed of a fractionally integrated shock around a potentially broken deterministic trend. Our proposed test is constructed from data which are de-trended allowing for a trend break whose (unknown) location is estimated by a standard residual sum of squares estimator applied either to the levels or first differences of the data, depending on the value specified for the long memory parameter under the null hypothesis. We demonstrate that the resulting LM-type statistic has a standard limiting null chi-squared distribution with one degree of freedom, and attains the same asymptotic local power function as an infeasible LM test based on the true shocks. Our proposed test therefore attains the same asymptotic local optimality properties as an oracle LM test in both the trend break and no trend break environments. Moreover, this asymptotic local power function does not alter between the break and no break cases and so there is no loss in asymptotic local power from allowing for a trend break at an unknown point in the sample, even in the case where no break is present. We also report the results from a Monte Carlo study into the finite-sample behaviour of our proposed test.
Estimation of Visual Shoreline Navigation Errors
Authors: Grishin Vladimir A.
Published: November 2018

In some cases, navigation of aircraft or spacecraft may need to be conducted in a Global Navigation Satellite System (GNSS)-denied environment. So, additional sources of navigation information may need to be used to increase navigation precision and resilience. Such sources can include visual navigation systems such as visual shoreline navigation. The main feature of visual shoreline navigation is the severe variability of navigation errors depending on the shape of the observed shoreline, the distance and the view angle of the observation. Such variations are so great that it is not possible to use average values of errors. So, each measurement of an aircraft or spacecraft position should be accompanied with an estimation of the error covariance matrix in real time. It is proposed to use the Cramer-Rao lower bound of visual shoreline navigation errors as such a matrix. The method for constructing the Cramer-Rao lower bound is described in this paper.
Mild Traumatic Brain Injury Burden Moderates the Relationship Between Cognitive Functioning and Suicidality in Iraq/Afghanistan-Era Veterans
Authors: Crocker Laura D. , Keller Amber V. , Jurick Sarah M. , Bomyea Jessica , Hays Chelsea C. , Twamley Elizabeth W. , Jak Amy J.
Published: November 2018

Objectives:Suicidal ideation (SI) is highly prevalent in Iraq/Afghanistan-era veterans with a history of mild traumatic brain injury (mTBI), and multiple mTBIs impart even greater risk for poorer neuropsychological functioning and suicidality. However, little is known about the cognitive mechanisms that may confer increased risk of suicidality in this population. Thus, we examined relationships between neuropsychological functioning and suicidality and specifically whether lifetime mTBI burden would moderate relationships between cognitive functioning and suicidal ideation.Methods:Iraq/Afghanistan-era Veterans with a history of mTBI seeking outpatient services (N= 282) completed a clinical neuropsychological assessment and psychiatric and postconcussive symptom questionnaires.Results:Individuals who endorsed SI reported more severe post-traumatic stress disorder (PTSD), depression, and postconcussive symptoms and exhibited significantly worse memory performance compared to those who denied SI. Furthermore, mTBI burden interacted with both attention/processing speed and memory, such that poorer performance in these domains was associated with greater likelihood of SI in individuals with a history of three or more mTBIs. The pattern of results remained consistent when controlling for PTSD, depression, and postconcussive symptoms.Conclusions:Slowed processing speed and/or memory difficulties may make it challenging to access and use past experiences to solve current problems and imagine future outcomes, leading to increases in hopelessness and SI in veterans with three or more mTBIs. Results have the potential to better inform treatment decisions for veterans with history of multiple mTBIs. (JINS, 2019, 25, 79–89)