bluuebunny/crossref_metadata_2025 huggingface dataset:
Plug & produce by modelling skills and service-oriented orchestration of reconfigurable manufacturing systems
Authors: Pfrommer Julius , Stogl Denis , Aleksandrov Kiril , Escaida Navarro Stefan , Hein Björn , Beyerer Jürgen
Published: October 2015

Shortening product lifecycles and small lot sizes require manufacturing systems to adapt increasingly fast. Many existing machine
tools, handling and logistics systems provide a generic functionality that is not bound to a specific product. But this flexibility and
reconfigurability on the level of individual resources is lost in automated systems that are limited to the production of a fixed set
of product variants. We propose a unified abstraction for the skills provided by the available resources and the product-specific
manufacturing requirements. From these high-level descriptions, executable manufacturing procedures are derived, exposed as services
and dynamically orchestrated at runtime in order to achieve the manufacturing goals.
Model-based development of products, processes and production resources
Authors: Dumitrescu Roman , Bremer Christian , Kühn Arno , Trächtler Ansgar , Frieben Tanja
Published: October 2015

This contribution applies methods and languages of Model-Based Systems Engineering to the field of production system engineering. The goal is an integrated modeling of objects, processes and systems. This approach improves knowledge transfer between the stakeholders involved and enables model-based design and verification.
Industrie 4.0 – technological approaches, use cases, and implementation
Authors: Anderl Reiner
Published: October 2015

Industrie 4.0 aims at improving value chains and value-added networks in industry. Technologically the approach is based on the
introduction of cyber-physical systems. Their capabilities form the basis for smart systems. This paper presents technological
approaches for Industrie 4.0 and introduces use cases as a specification technique for application scenarios. A demonstrator for
additive manufacturing is presented. Lessons learnd from this demonstrator have led to the definition of capabilities for vertical and
horizontal integration within Industrie 4.0.
Cyber-physical production systems: roots from manufacturing science and technology
Authors: Monostori László
Published: October 2015

One of the most significant directions in the development of computer science and information and communication technologies is
represented by Cyber-Physical Systems (CPS) which are systems of collaborating computational entities which are in intensive
connection with the surrounding physical world and its on-going processes, providing and using, at the same time, data-accessing and
data-processing services available on the internet. Cyber-Physical Production Systems (CPPS), relying on the newest and
foreseeable further developments of computer science, information and communication technologies on the one hand, and of manufacturing
science and technology, on the other, may lead to the 4th Industrial Revolution, frequently noted as Industrie 4.0. The paper
underlines that there are significant roots generally – and particularly in the CIRP community – which point towards
CPPS. Expectations and the related new R&D challenges are also outlined.
Milton Friedman on Freedom and the Negative Income Tax
Authors: Preiss Joshua
Published: October 2015

In addition to his Noble Prize-winning work in economics, Milton Friedman produced some of the most influential philosophical work on the role of government in a free society. Despite his great influence, there remains a dearth of scholarship on Friedman’s social and political philosophy. This paper helps to fill this large void by providing a conceptual analysis of Friedman’s theory of freedom. In addition, I argue that a careful reading of his arguments for freedom ought to lead Friedman, and like-minded liberals and libertarians, to give absolute priority to his negative income tax proposal. A substantial basic income furthers effective economic freedom (on Friedman’s own understanding), redeems his central claim that markets enable cooperation without coercion, and enables him to address his lifelong interlocutors by mitigating concerns for the ways in which economic dependence and inequality undermine both freedom and democratic legitimacy.
Simulation of varying femoral attachment sites of medial patellofemoral ligament using a musculoskeletal multi-body model
Authors: Geier A. , Tischer T. , Bader R.
Published: October 2015

The medial patellofemoral ligament (MPFL) is a key structure in the treatment of habitual and traumatic patellofemoral instability. However, there exists little knowledge about its behaviour during deep knee flexion after femoral refixation. Since improper femoral attachment sites may lead to unnatural length change patterns in the ligament and consequently to osteoarthritis due to pathological femoro-patellar contact pressure, the understanding of the patella kinematics and MPFL behaviour is crucial.

The purpose of this numerical study was to compute the six-degree-of-freedom motion pattern of the human patella during deep knee flexion for systematic analysis of varying landmarks for the femoral attachment in medial patellofemoral ligament reconstruction surgery by means of multibody simulation.

Therefore, based on a previously presented musculoskeletal model [1] the dynamic pathways of the patella were computed. Then, the spatial motion was approximated by rheonomic polynomials and exploited for systematic evaluation of the MPFL length change patterns. Hence, 16 femoral attachment points at a radius of 5 mm and 10 mm around the radiographic centre point [2] were defined and the absolute length changes were recorded during deep knee flexion to 120 degree.

This approach allows for a systematic evaluation of numerous MPFL attachment sites while exploiting the physiological patella kinematics. The patella kinematics including shift, flexion, tilt and rotation as well as the MPFL length change patterns were consistent to in vitro and in vivo data in the literature [3–7] and therefore indicate validity of the numerical approach. The parameter study on the femoral attachment site should enable to determine the most isometric point and non-isometric variations corresponding to patellofemoral instability, arthritis or high graft load.
Type II ancient compact solutions to the Yamabe flow
Authors: Daskalopoulos Panagiota , del Pino Manuel , Sesum Natasa
Published: October 2015

We construct new type II ancient compact solutions to the Yamabe flow. Our solutions
are rotationally symmetric and converge, as

t
→

-
∞

{t\to{-}\infty}

, to a tower of two spheres.
Their curvature operator changes sign.
We allow two time-dependent parameters in our ansatz. We use perturbation theory, via fixed point arguments,
based on sharp estimates on ancient solutions of the approximated linear equation
and careful estimation of the error terms which allow us to make the right choice of parameters.
Our technique may be viewed as a parabolic analogue of gluing two exact solutions to the rescaled equation, that is the spheres, with narrow cylindrical necks to obtain a new ancient solution to the Yamabe flow. The result
generalizes to the gluing of k spheres for any

k
≥
2

{k\geq 2}

, in such a way the configuration of radii of the spheres glued is driven as

t
→

-
∞

{t\to{-}\infty}

by a First order Toda system.
Intrinsic flat stability of the positive mass theorem
for graphical hypersurfaces of Euclidean space
Authors: Huang Lan-Hsuan , Lee Dan A. , Sormani Christina
Published: October 2015

The rigidity of the Positive Mass Theorem states that the only complete asymptotically flat manifold of nonnegative scalar curvature and zero mass is Euclidean space. We study the stability of this statement for spaces that can be realized as graphical hypersurfaces in

𝔼

n
+
1

{\mathbb{E}^{n+1}}

.
We prove (under certain technical hypotheses) that if a sequence of complete asymptotically flat graphs of nonnegative scalar curvature has mass approaching 0, then the sequence must converge to Euclidean space in the pointed intrinsic flat sense. The appendix
includes a new Gromov–Hausdorff and intrinsic flat
compactness theorem for sequences of metric spaces with uniform Lipschitz bounds on their metrics.
Addendum: The case of closed surfaces (Boundary value problems on planar graphs and flat surfaces with integer cone singularities I: The Dirichlet problem)
Authors: Hersonsky Sa'ar
Published: October 2015

We extend our discrete uniformization theorems for planar, m-connected, Jordan domains [J. reine angew. Math. 670 (2012), 65–92] to closed surfaces of genus m ≥ 1.
Vector valued theta functions associated with binary quadratic forms
Authors: Ehlen Stephan
Published: October 2015

We study the space of vector valued theta functions for the Weil representation of a positive definite even lattice of rank two
with fundamental discriminant.
We work out the relation of this space to the corresponding scalar valued theta functions of weight one
and determine an orthogonal basis with respect to the Petersson inner product.
Moreover, we give an explicit formula for the Petersson norms of the elements of this basis.
Utilization of walnut shell as a feedstock for preparing high surface area activated carbon by microwave induced activation: effect of activation agents
Authors: Xia Hongying , Cheng Song , Zhang Libo , Peng Jinhui
Published: October 2015

The present work attempts to convert walnut shell into a high surface area activated carbon by microwave heating and chemical activation. Different activation agents such as KOH, NaOH, K2CO3 and Na2CO3 were utilized to identify a suitable activation agent. The result indicated that KOH was the most suitable activation agent among those agents, with the highest porosity and surface area of activated carbon. The effect of KOH/C mass ratio on the pore structure characteristics of the activated carbon was investigated. An optimal KOH/C mass ratio of 4 was identified, beyond which the surface area as well as the pore volume were found to decrease. The surface area and the pore volume were estimated to be 3276 m2/g and 1.952 ml/g, respectively, meanwhile the microporous proportion was 77.51% under the optimized KOH/C mass ratio. The activated carbon was further characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The findings strongly support that the activation agent has a great effect on the preparation of activated carbon from walnut shell.
Isolating nanocellulose fibrills from bamboo parenchymal cells with high intensity ultrasonication
Authors: Wang Hankun , Zhang Xuexia , Jiang Zehui , Yu Zixuan , Yu Yan
Published: October 2015

The parenchymal cells in bamboo are an attractive source of raw materials due to their low degree of lignification and relatively loose cell wall structures. In this study, nanocellulose fibrils (NCFs) were isolated via a combined process of ultrasonication and chemical pretreatment of parenchymal cells separated from Moso bamboo (Phyllostachys pubescens) by means of a simple screening approach. As indicators of the fibrillation degree served the morphology, optical properties, and dynamic viscosity of the prepared NCF hydrogel as function of ultrasonication time. The mechanical properties of NCF derived films were also determined. The results show that high-quality NCFs can easily be prepared from bamboo parenchymal cells through the above-mentioned process, with an optimal ultrasonication time of 40 min. The utilization of bamboo processing residues via the ultrasonication route is promising and for energy saving production of high-quality NCFs at large scale.
On the challenges of measuring humor styles: Response to Heintz and Ruch
Authors: Martin Rod A.
Published: October 2015

I applaud Heintz and Ruch (this issue) for their efforts at evaluating the construct validity of the Humor Styles Questionnaire (HSQ). However, their study has several weaknesses that limit the conclusions that can be drawn. Most importantly, the measures developed by these authors to test the validity of the HSQ have questionable reliability and validity themselves, due to the challenges inherent in measuring humor styles via self-report. These limitations are discussed, and suggestions are provided for further research along these lines.
A dual-processing approach to the effects of viewing political comedy
Authors: Warner Benjamin R. , Hawthorne Hayley Jeanne , Hawthorne Joshua
Published: October 2015

Stephen Colbert’s announcement that he would take over
CFD Modeling of Algae Flash Pyrolysis in the Batch Fluidized Bed Reactor Including Heat Carrier Particles
Authors: Azizi Salar , Mowla Dariush
Published: October 2015

The algae biomass is one of the potential biomass resources for extracting lipid to produce fuel. The off grade or residuals of dehydrated algae particles can be used in pyrolysis reactions to produce fuel or useful chemicals. Due to higher ash contents of algae biomass, pyrolysis process needs an appropriate design of pyrolysis reactor. The heating rate of algae biomass is a key factor for increasing of bio-oil production rate. Instead of heat transfer from reactor walls to the biomass, heated inert particles are added to the conventional fluidized bed reactor to increase heat transfer rate and yield of the bio-oil as called flash pyrolysis. The introduced pyrolysis reaction in the novel heating method of fluidized bed reactor studied numerically. For this purpose, an Eulerian-Eulerian CFD model utilized for modeling of the dehydrated algae pyrolysis in the fluidized bed reactor. The appropriate reaction rate of the algae pyrolysis is based on the heating rate, temperature sensitive activation energy and the reaction selectivity utilized to the algae pyrolysis. In addition, the segregation and density change of the biomass particles investigated in the CFD modeling to analysis mixing of the particles and corresponding heat transfer between the mixed particles. The validation of the CFD model investigated using results of prepared experimental setup.
Modeling and Simulation of a Co-current Rotary Dryer
Authors: Huang Zhi-gang , Weng Yun-xuan , Fu Nan , Fu Zong-qiang , Li Dong , Chen Xiao Dong
Published: October 2015

Mathematical models including mass and energy conservation were developed in order to predict the outlet particles temperature and moisture. As the inlet air temperature increased, the outlet particles temperature increased as well and the outlet particles moisture decreased quickly. The outlet particles temperature and moisture changed a little as a function of the speed of rotation at the low inlet air temperature, while the outlet particles temperature and moisture increased very apparently with the speed of rotation increased at the high inlet air temperature. The error of the simulation results compared to the experimental data showed good accuracy for particles temperature and moisture content. The mathematical model performs well to predict the outlet particles temperature and moisture content.
A unified approach to convergence rates for ℓ1-regularization
and lacking sparsity
Authors: Flemming Jens , Hofmann Bernd , Veselić Ivan
Published: October 2015

In ℓ1-regularization, which is an important tool in signal and image processing, one usually is concerned with signals
and images having a sparse representation in some suitable basis, e.g., in a wavelet basis.
Many results on convergence and convergence rates of sparse approximate solutions to linear ill-posed problems are known, but rate results
for the ℓ1-regularization in case of lacking sparsity had not been published until 2013.
In the last two years, however, two articles appeared providing sufficient conditions for convergence rates in case of non-sparse
but almost sparse solutions.
In the present paper, we suggest a third sufficient condition, which unifies the existing two and,
by the way, also incorporates the well-known restricted isometry property.
A Self-Driven and Adaptive Adjusting Teaching Learning Method for Optimizing Optical Multicast Network Throughput
Authors: Liu Huanlin , Xu Yifan , Chen Yong , Zhang Mingjia
Published: October 2015

With the development of one point to multiple point applications, network resources become scarcer and wavelength channels become more crowded in optical networks. To improve the bandwidth utilization, the multicast routing algorithm based on network coding can greatly increase the resource utilization, but it is most difficult to maximize the network throughput owing to ignoring the differences between the multicast receiving nodes. For making full use of the destination nodes’ receives ability to maximize optical multicast’s network throughput, a new optical multicast routing algorithm based on teaching-learning-based optimization (MR-iTLBO) is proposed in the paper. In order to increase the diversity of learning, a self-driven learning method is adopted in MR-iTLBO algorithm, and the mutation operator of genetic algorithm is introduced to prevent the algorithm into a local optimum. For increasing learner’s learning efficiency, an adaptive learning factor is designed to adjust the learning process. Moreover, the reconfiguration scheme based on probability vector is devised to expand its global search capability in MR-iTLBO algorithm. The simulation results show that performance in terms of network throughput and convergence rate has been improved significantly with respect to the TLBO and the variant TLBO.
“Lex Mahometi”. The Authority of a Pattern of Religious Polemics
Authors: Tischler Matthias M.
Published: October 2015

The purpose of this paper is to show how Latin-Christian intellectuals, especially from the twelfth and thirteenth centuries onwards, learned not only to use the new term ‘religious law’ (“lex”) within their modes of cultural comparison and othering as a pattern of religious polemics, but also as a means of dis/integrating and historicizing Islam as a new (religious) law and its lawgiver Muḥammad within a whole system of legal thought (natural law, divine law, written law ...) and a religious world order arranged between divine transcendence and human immanence. The paradoxical but enduring consequence of this very productive mistake of comparing incomparable but always personalized conceptions of religion is that Islam found its place within the Occidental system of institutionalized monotheisms.
Textual Rearrangement and Thwarted Intentions. The Two Versions of the Latin Talmud
Authors: Fidora Alexander
Published: October 2015

The
Fourteenth-Century Portolan Charts. Challenges to our Understanding of Cross-Cultural Relationships in the Mediterranean and Black Sea Regions and of (Knowledge?) Practices of Chart-Makers
Authors: Brentjes Sonja
Published: October 2015

This article studies five well-known portolan charts of the fourteenth century, produced at Genoa, Ciutat de Majorca and Venice, with regard to the knowledge their makers used for visualizing physical and human geography in Eastern Europe, Northern Africa and Iraq. It studies four so-called compound images to understand the cultural background of the chosen pictorial and verbal representation instead of analyzing single geographical objects. The results of the analysis strongly suggest that the portolan chart-makers had access to visual material from several cultures around the Mediterranean and Western Asia and that they cooperated creatively with (unknown) members of larger social, economic and cultural networks.
Healthcare workers’ training and information levels over an occupationally acquired Ebola virus disease
Authors: Seeger Florian H. , Wicker Sabine , Rabenau Holger F. , Wolf Timo , Gottschalk René
Published: October 2015

Background: Hundreds of West African healthcare workers (HCW) have become ill with Ebola virus disease (EVD) and died during the recent outbreak. The occurrence of occupational infections in laboratories could be due to the lack of use of personal protective equipment, the failure to implement specific regulations about the use of equipment and how to work with hazardous materials. Our study attempted to assess the information as well as training level of HCW of a German high level isolation unit and their concern over an occupationally acquired EVD.

Methods: During the recent Ebola virus outbreak a survey was conducted among HCWs, using an anonymous questionnaire.

Results: Although 70% of our total study population stated that they have all the information needed to care for Ebola patients, only 18.2% of laboratory workers and 29.4% of the HCW of the virology department felt sufficiently trained. The HCW rated the Internet (64.3%) and the daily press (54.3%) as the most important sources of information. Medical literature (45.7%) and official institutions (40.4%) were rated less often.

Conclusions: Formulated pointedly, the HCW turned to popular science to get the information they need to feel safe. Further in house training regarding practical skills and reference to scientific literature would be a better solution to ensure workplace safety.
The private life of stops: VOT in a real-time corpus of spontaneous Glaswegian
Authors: Stuart-Smith Jane , Sonderegger Morgan , Rathcke Tamara , Macdonald Rachel
Published: October 2015

While voice onset time (VOT) is known to be sensitive to a range of phonetic and linguistic factors, much less is known about VOT in spontaneous speech, since most studies consider stops in single words, in sentences, and/or in read speech. Scottish English is typically said to show less aspirated voiceless stops than other varieties of English, but there is also variation, ranging from unaspirated stops in vernacular speakers to more aspirated stops in Scottish Standard English; change in the vernacular has also been suggested. This paper presents results from a study which used a fast, semi-automated procedure for analyzing positive VOT, and applied it to stressed syllable-initial stops from a real- and apparent-time corpus of naturally-occurring spontaneous Glaswegian vernacular speech. We confirm significant effects on VOT for place of articulation and local speaking rate, and trends for vowel height and lexical frequency. With respect to time, our results are not consistent with previous work reporting generally shorter VOT in elderly speakers, since our results from models which control for local speech rate show lengthening over real-time in the elderly speakers in our sample. Overall, our findings suggest that VOT in both voiceless and voiced stops is lengthening over the course of the twentieth century in this variety of Scottish English. They also support observations from other studies, both from Scotland and beyond, indicating that gradient shifts along the VOT continuum reflect subtle sociolinguistic control.
A new scintillation proximity assay-based approach for the detection of KRAS mutations
Authors: Lee So-Young , Lim Jae-Cheong , Cho Eun-Ha , Jung Sung-Hee
Published: October 2015

KRAS is very commonly mutated resulting in a constitutively activated protein, which is independent of epidermal growth factor receptor
(EGFR) ligand binding and resistant to anti-EGFR therapy. Although KRAS is frequently studied, there is still no uniform standard for
detecting of KRAS mutations. In this report, a new scintillation proximity assay-based approach is described that determines the
relative affinities of wild-type and mutated KRAS to the anti-KRAS antibody. We performed in vitro experiments using normal
human colonic cells (CCD18Co), KRAS wild type (Caco-2) and KRAS mutant (HCT 116) cell lines to determine the
relative affinities of wild type or mutated KRAS toward an anti-KRAS monoclonal antibody. The process consists of two primary steps:
immunoprecipitation from cell lysate to enrich the KRAS protein and the scintillation proximity assay of the immunoprecipitant to
determine the relative affinity against the antibody. A fixed concentration of cell lysates was purified by the immunoprecipitation
method. The expressions of the KRAS protein in all cell lines was quantitatively confirmed by western blot analysis. For the
scintillation proximity assay, the KRAS standard protein was radiolabeled with 125I by a simple mixing process in the
iodogen tube immediately at room temperature immediately before use. The obtained CPM (count per minute) values of were used to
calculate the KRAS concentration using purified KRAS as the standard. The calculated relative affinities of 7 μg of
Caco-2 and HCT 116 immunoprecipitants for the anti-KRAS antibody were 77 and 0%, respectively. The newly developed
scintillation proximity assay-based strategy determines the relative affinities of wild-type or mutated KRAS towards the anti-KRAS
monoclonal antibody. This determination can help distinguish mutated KRAS from the wild type protein. The new SPA based approach for
detecting KRAS mutations is applicable to many other cancer-related mutations.
The Praise of God and His Name as the Core of the Second Temple Liturgy
Authors: Pajunen Mika S.
Published: October 2015

Das Lob Gottes wurde schon immer als wichtigstes Element des liturgischen Lebens am 2. Tempel verstanden. Formkritiker haben dieses Moment der liturgischen Praxis vor allem durch die Analyse der Psalmen nachgezeichnet. Demgegenüber erscheint die Rolle der Klage zumindest in der späten Phase des 2. Temepls randständig. Allerdings fehlt ein Bindeglied zwischen der hellenistischen Phase der Liturgie und dem Lob in den Qumran Texten des 1 Jh. v. Chr. Der Blick auf das Motiv der Schöpfung erschließt dieses Bindeglied und erklärt zugleich, warum das Lob als Verpflichtung Gott gegenüber verstanden wurde.

Praise of God has always been understood by scholars as a primary element of the liturgical life of the Second Temple period. Form-critics have situated the praises of God in the liturgical practice of the period most of all by analyzing the Psalms now in the MT Psalter. However, at least in the late Second Temple period the role of laments seems to be marginal. Thus far a link has been missing in scholarship between this centrality of praise perceivable in the liturgical practice of the Hellenistic period and the all-encompassing nature of praise in the texts of the Qumran movement from the first century BCE. This is a link that may in part explain why prayer, or during this time more properly praise, came to be seen in early Judaism as an obligation towards God. This question is explored by investigating how the Second Temple liturgy is in many texts from the second century BCE given an explicit basis in the creation, and how such traditions in turn served an important function in the composition of new liturgical texts.

La louange de Dieu a toujours été comprise par les exégètes comme un élément essentiel de la vie liturgique de la période du Second Temple. A l’aide de la critique des formes, certains exégètes ont situé les louanges de Dieu dans la pratique liturgique de cette période, en analysant surtout les Psaumes actuellement présents dans le psautier du TM. Le rôle des lamentations, en revanche, semble marginal, au moins dans la période tardive du Second Temple. Jusqu’à présent la recherche n’a pas établi de lien entre la centralité de la louange perceptible dans la pratique liturgique de la période hellénistique et l’importancede la louange dans les textes qumrâniens du premier siècle av. J.-C. Ce lien pourrait expliquer, en partie, pourquoi la prière, ou à plus proprement parler la louange, a été de plus en plus perçue, durant cette période, comme une obligation envers Dieu dans le judaïsme primitif. Cette question est explorée à travers l’analyse de nombreux textes du deuxième siècle av. J.-C. qui montrent comment la liturgie du Second Temple a été basée explicitement sur la Création et comment de telles traditions ont occupé en retour une place importante dans la composition de nouveaux textes liturgiques.
SPME collection and GC-MS analysis of volatiles emitted during the attack of male Polygraphus poligraphus (Coleoptera, Curcolionidae) on Norway spruce
Authors: Rahmani Rizan , Hedenström Erik , Schroeder Martin
Published: October 2015

Tree mortality caused by bark beetles has increased in recent decades in both Europe and North America. In a large recent outbreak in central Sweden the bark beetle Polygraphus poligraphus was often found together with the spruce bark beetle Ips typographus in killed trees. To increase the understanding of the aggregation behavior of P. poligraphus we used solid phase microextraction (SPME) to collect volatile organic compounds (VOCs) released from single P. poligraphus males, with and without added females, colonizing Norway spruce stem sections and analyzed the sampled compounds by combined gas chromatography and mass spectrometry (GC-MS). High amounts of terpinen-4-ol, a substance found in the hindguts of P. poligraphus males in earlier studies, were released by colonizing males. The emission of both enantiomers of terpinen-4-ol was monitored by GC-MS over time as the males aged in the absence and presence of females. Single males emitted (R)-(–)-terpinen-4-ol for up to 60 days in high enantiomeric purity but the enantiomeric excess (ee) varied between males, and also for the same individual, over time from 96.3% to 99.3% ee. In the presence of females, males also emitted terpinen-4-ol for up to 50 days but now in lower amounts and with lower enantiomeric purity varying from 67.7% ee to 99.3% ee. Small quantities of other volatile compounds were emitted from the colonizing beetles including cis- and trans-4-thujanol, both of which were previously shown to be present in the hindguts of males. In earlier studies frontalin was found to attract P. poligraphus, but in our study it was not identified among emitted compounds from colonizing beetles.
Near-Critical Dynamics in Stimulus-Evoked Activity of the Human Brain and Its Relation to Spontaneous Resting-State Activity
Authors: Arviv Oshrit , Goldstein Abraham , Shriki Oren
Published: October 2015

In recent years, numerous studies have found that the brain at resting state displays many features characteristic of a critical state. Here we examine whether stimulus-evoked activity can also be regarded as critical. Additionally, we investigate the relation between resting-state activity and stimulus-evoked activity from the perspective of criticality. We found that cortical activity measured by magnetoencephalography (MEG) is near critical and organizes as neuronal avalanches at both resting-state and stimulus-evoked activities. Moreover, a significantly high intrasubject similarity between avalanche size and duration distributions at both cognitive states was found, suggesting that the distributions capture specific features of the individual brain dynamics. When comparing different subjects, a higher intersubject consistency was found for stimulus-evoked activity than for resting state. This was expressed by the distance between avalanche size and duration distributions of different participants and was supported by the spatial spreading of the avalanches involved. During the course of stimulus-evoked activity, time locked to the stimulus onset, we demonstrate fluctuations in the gain of the neuronal system and thus short timescale deviations from the critical state. Nonetheless, the overall near-critical state in stimulus-evoked activity is retained over longer timescales, in close proximity and with a high correlation to spontaneous (not time-locked) resting-state activity. Spatially, the observed fluctuations in gain manifest through anticorrelative activations of brain sites involved, suggesting a switch between task-negative (default mode) and task-positive networks and assigning the changes in excitation–inhibition balance to nodes within these networks. Overall, this study offers a novel outlook on evoked activity through the framework of criticality.

SIGNIFICANCE STATEMENTThe organization of stimulus-evoked activity and ongoing cortical activity is a topic of high importance. The article addresses several general questions. What is the spatiotemporal organization of stimulus-evoked cortical activity in healthy human subjects? Are there deviations from excitation–inhibition balance during stimulus-evoked activity? What is the relationship between stimulus-evoked activity and ongoing resting-state activity? Using magnetoencephalography (MEG), we demonstrate that stimulus-evoked activity in humans follows a critical branching process that produces neuronal avalanches. Additionally, we investigate the spatiotemporal relationship between resting-state activity and stimulus-evoked activity from the perspective of critical dynamics. These analyses reveal new aspects of this complex relationship and offer novel insights into the interplay between excitation and inhibition that were not observed previously using conventional approaches.
State and Trait Components of Functional Connectivity: Individual Differences Vary with Mental State
Authors: Geerligs Linda , Rubinov Mikail , Cam-CAN  , Henson Richard N.
Published: October 2015

Resting-state functional connectivity, as measured by functional magnetic resonance imaging (fMRI), is often treated as a trait, used, for example, to draw inferences about individual differences in cognitive function, or differences between healthy or diseased populations. However, functional connectivity can also depend on the individual's mental state. In the present study, we examined the relative contribution of state and trait components in shaping an individual's functional architecture. We used fMRI data from a large, population-based human sample (N= 587, age 18–88 years), as part of the Cambridge Centre for Aging and Neuroscience (Cam-CAN), which were collected in three mental states: resting, performing a sensorimotor task, and watching a movie. Whereas previous studies have shown commonalities across mental states in the average functional connectivity across individuals, we focused on the effects of states on the pattern of individual differences in functional connectivity. We found that state effects were as important as trait effects in shaping individual functional connectivity patterns, each explaining an approximately equal amount of variance. This was true when we looked at aging, as one specific dimension of individual differences, as well as when we looked at generic aspects of individual variation. These results show that individual differences in functional connectivity consist of state-dependent aspects, as well as more stable, trait-like characteristics. Studying individual differences in functional connectivity across a wider range of mental states will therefore provide a more complete picture of the mechanisms underlying factors such as cognitive ability, aging, and disease.

SIGNIFICANCE STATEMENTThe brain's functional architecture is remarkably similar across different individuals and across different mental states, which is why many studies use functional connectivity as a trait measure. Despite these trait-like aspects, functional connectivity varies over time and with changes in cognitive state. We measured connectivity in three different states to quantify the size of the trait-like component of functional connectivity, compared with the state-dependent component. Our results show that studying individual differences within one state (such as resting) uncovers only part of the relevant individual differences in brain function, and that the study of functional connectivity under multiple mental states is essential to disentangle connectivity differences that are transient versus those that represent more stable, trait-like characteristics of an individual.
Apoptosis of Oligodendrocytes during Early Development Delays Myelination and Impairs Subsequent Responses to Demyelination
Authors: Caprariello Andrew V. , Batt Courtney E. , Zippe Ingrid , Romito-DiGiacomo Rita R. , Karl Molly , Miller Robert H.
Published: October 2015

During mammalian development, myelin-forming oligodendrocytes are generated and axons ensheathed according to a tightly regulated sequence of events. Excess premyelinating oligodendrocytes are eliminated by apoptosis and the timing of the onset of myelination in any specific CNS region is highly reproducible. Although the developing CNS recovers more effectively than the adult CNS from similar insults, it is unknown whether early loss of oligodendrocyte lineage cells leads to long-term functional deficits. To directly assess whether the loss of oligodendrocytes during early postnatal spinal cord development impacted oligodendrogenesis, myelination, and remyelination, transgenic mouse lines were generated in which a modified caspase-9 molecule allowed spatial and temporal control of the apoptotic pathway specifically in mature, myelin basic protein expressing oligodendrocytes (MBP-iCP9). Activating apoptosis in MBP+cells of the developing spinal cord during the first postnatal week inhibited myelination. This inhibition was transient, and the levels of myelination largely returned to normal after 2 weeks. Despite robust developmental plasticity, MBP-iCP9-induced oligodendrocyte apoptosis compromised the rate and extent of adult remyelination. Remyelination failure correlated with a truncated proliferative response of oligodendrocyte progenitor cells, suggesting that depleting the oligodendrocyte pool during critical developmental periods compromises the regenerative response to subsequent demyelinating lesions.

SIGNIFICANCE STATEMENTThis manuscript demonstrates that early insults leading to oligodendrocyte apoptosis result in the impairment of recovery from demyelinating diseases in the adult. These studies begin to provide an initial understanding of the potential failure of recovery in insults, such as periventricular leukomalacia and multiple sclerosis.
Training-Associated Emotional Arousal Shapes Endocannabinoid Modulation of Spatial Memory Retrieval in Rats
Authors: Morena Maria , De Castro Valentina , Gray J. Megan , Palmery Maura , Trezza Viviana , Roozendaal Benno , Hill Matthew N. , Campolongo Patrizia
Published: October 2015

Variations in environmental aversiveness influence emotional memory processes in rats. We have previously shown that cannabinoid effects on memory are dependent on the stress level at the time of training as well as on the aversiveness of the environmental context. Here, we investigated whether the hippocampal endocannabinoid system modulates memory retrieval depending on the training-associated arousal level. Male adult Sprague Dawley rats were trained on a water maze spatial task at two different water temperatures (19°C and 25°C) to elicit either higher or lower stress levels, respectively. Rats trained under the higher stress condition had better memory and higher corticosterone concentrations than rats trained at the lower stress condition. The cannabinoid receptor agonist WIN55212-2 (10–30 ng/side), the 2-arachidonoyl glycerol (2-AG) hydrolysis inhibitor JZL184 (0.1–1 μg/side), and the anandamide (AEA) hydrolysis inhibitor URB597 (10–30 ng/side) were administered bilaterally into the hippocampus 60 min before probe-trial retention testing. WIN55212-2 or JZL184, but not URB597, impaired probe-trial performances only of rats trained at the higher stressful condition. Furthermore, rats trained under higher stress levels displayed an increase in hippocampal 2-AG, but not AEA, levels at the time of retention testing and a decreased affinity of the main 2-AG-degrading enzyme for its substrate. The present findings indicate that the endocannabinoid 2-AG in the hippocampus plays a key role in the selective regulation of spatial memory retrieval of stressful experience, shedding light on the neurobiological mechanisms involved in the impact of stress effects on memory processing.

SIGNIFICANCE STATEMENTEndogenous cannabinoids play a central role in the modulation of memory for emotional events. Here we demonstrate that the endocannabinoid 2-arachidonoylglycerol in the hippocampus, a brain region crucially involved in the regulation of memory processes, selectively modulates spatial memory recall of stressful experiences. Thus, our findings provide evidence that the endocannabinoid 2-arachidonoylglycerol is a key player in mediating the impact of stress on memory retrieval. These findings can pave the way to new potential therapeutic intervention for the treatment of neuropsychiatric disorders, such as post-traumatic stress disorder, where a previous exposure to traumatic events could alter the response to traumatic memory recall leading to mental illness.
Transcriptomic Approaches to Neural Repair
Authors: Dulin Jennifer N. , Antunes-Martins Ana , Chandran Vijayendran , Costigan Michael , Lerch Jessica K. , Willis Dianna E. , Tuszynski Mark H.
Published: October 2015

Understanding why adult CNS neurons fail to regenerate their axons following injury remains a central challenge of neuroscience research. A more complete appreciation of the biological mechanisms shaping the injured nervous system is a crucial prerequisite for the development of robust therapies to promote neural repair. Historically, the identification of regeneration associated signaling pathways has been impeded by the limitations of available genetic and molecular tools. As we progress into an era in which the high-throughput interrogation of gene expression is commonplace and our knowledge base of interactome data is rapidly expanding, we can now begin to assemble a more comprehensive view of the complex biology governing axon regeneration. Here, we highlight current and ongoing work featuring transcriptomic approaches toward the discovery of novel molecular mechanisms that can be manipulated to promote neural repair.

SIGNIFICANCE STATEMENTTranscriptional profiling is a powerful technique with broad applications in the field of neuroscience. Recent advances such as single-cell transcriptomics, CNS cell type-specific and developmental stage-specific expression libraries are rapidly enhancing the power of transcriptomics for neuroscience applications. However, extracting biologically meaningful information from large transcriptomic datasets remains a formidable challenge. This mini-symposium will highlight current work using transcriptomic approaches to identify regulatory networks in the injured nervous system. We will discuss analytical strategies for transcriptomics data, the significance of noncoding RNA networks, and the utility of multiomic data integration. Though the studies featured here specifically focus on neural repair, the approaches highlighted in this mini-symposium will be of broad interest and utility to neuroscientists working in diverse areas of the field.
Chaperones in Neurodegeneration
Authors: Lindberg Iris , Shorter James , Wiseman R. Luke , Chiti Fabrizio , Dickey Chad A. , McLean Pamela J.
Published: October 2015

Cellular protein homeostasis (proteostasis) maintains the integrity of the proteome and includes protein synthesis, folding, oligomerization, and turnover; chaperone proteins assist with all of these processes. Neurons appear to be especially susceptible to failures in proteostasis, and this is now increasingly recognized as a major origin of neurodegenerative disease. This review, based on a mini-symposium presented at the 2015 Society for Neuroscience meeting, describes new work in the area of neuronal proteostasis, with a specific focus on the roles and therapeutic uses of protein chaperones. We first present a brief review of protein misfolding and aggregation in neurodegenerative disease. We then discuss different aspects of chaperone control of neuronal proteostasis on topics ranging from chaperone engineering, to chaperone-mediated blockade of protein oligomerization and cytotoxicity, to the potential rescue of neurodegenerative processes using modified chaperone proteins.

SIGNIFICANCE STATEMENTAberrant protein homeostasis within neurons results in protein misfolding and aggregation. In this review, we discuss specific roles for protein chaperones in the oligomerization, assembly, and disaggregation of proteins known to be abnormally folded in neurodegenerative disease. Collectively, our goal is to identify therapeutic mechanisms to reduce the cellular toxicity of abnormal aggregates.
How Does the Brain Implement Adaptive Decision Making to Eat?
Authors: Compan Valérie , Walsh B. Timothy , Kaye Walter , Geliebter Allan
Published: October 2015

Adaptive decision making to eat is crucial for survival, but in anorexia nervosa, the brain persistently supports reduced food intake despite a growing need for energy. How the brain persists in reducing food intake, sometimes even to the point of death and despite the evolution of multiple mechanisms to ensure survival by governing adaptive eating behaviors, remains mysterious. Neural substrates belong to the reward-habit system, which could differ among the eating disorders. The present review provides an overview of neural circuitry of restrictive food choice, binge eating, and the contribution of specific serotonin receptors. One possibility is that restrictive food intake critically engages goal-directed (decision making) systems and “habit,” supporting the view that persistent caloric restriction mimics some aspects of addiction to drugs of abuse.

SIGNIFICANCE STATEMENTAn improved understanding of the neural basis of eating disorders is a timely challenge because these disorders can be deadly. Up to 70 million of people in the world suffer from eating disorders. Anorexia nervosa affects 1–4% of women in United States and is the first cause of death among adolescents in Europe. Studies relying on animal models suggest that decision making to eat (or not) can prevail over actual energy requirements due to emotional disturbances resulting in abnormal habitual behavior, mimicking dependence. These recent studies provide a foundation for developing more specific and effective interventions for these disorders.
New Insights on Astrocyte Ion Channels: Critical for Homeostasis and Neuron-Glia Signaling
Authors: Olsen Michelle L. , Khakh Baljit S. , Skatchkov Serguei N. , Zhou Min , Lee C. Justin , Rouach Nathalie
Published: October 2015

Initial biophysical studies on glial cells nearly 50 years ago identified these cells as being electrically silent. These first studies also demonstrated a large K+conductance, which led to the notion that glia may regulate extracellular K+levels homeostatically. This view has now gained critical support from the study of multiple disease models discussed herein. Dysfunction of a major astrocyte K+channel, Kir4.1, appears as an early pathological event underlying neuronal phenotypes in several neurodevelopmental and neurodegenerative diseases. An expanding list of other astrocyte ion channels, including the calcium-activated ion channel BEST-1, hemichannels, and two-pore domain K+channels, all contribute to astrocyte biology and CNS function and underpin new forms of crosstalk between neurons and glia. Once considered merely the glue that holds the brain together, it is now increasingly recognized that astrocytes contribute in several fundamental ways to neuronal function. Emerging new insights and future perspectives of this active research area are highlighted within.

SIGNIFICANCE STATEMENTThe critical role of astrocyte potassium channels in CNS homeostasis has been reemphasized by recent studies conducted in animal disease models. Emerging evidence also supports the signaling role mediated by astrocyte ion channels such as BEST1, hemichannels, and two-pore channels, which enable astrocytes to interact with neurons and regulate synaptic transmission and plasticity. This minisymposium highlights recent developments and future perspectives of these research areas.