bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adrenergic agonist induces rhythmic firing in quiescent cardiac preganglionic neurons in nucleus ambiguous via activation of intrinsic membrane excitability
Authors: Aiba Isamu , Noebels Jeffrey L. 
Published: March 2018

AbstractCholinergic vagal nerves projecting from neurons in the brainstem nucleus ambiguus (NAm) play a predominant role in cardiac parasympathetic pacemaking control. Central adrenergic signaling modulates the tone of this vagal output; however the exact excitability mechanisms are not fully understood. We investigated responses of NAm neurons to adrenergic agonists using in vitro mouse brainstem slices. Preganglionic NAm neurons were identified by Chat-tdtomato fluorescence in young adult transgenic mice and their cardiac projection confirmed by retrograde dye tracing. Juxtacellular recordings detected sparse or absent spontaneous action potentials (AP) in NAm neurons. However bath application of epinephrine or norepinephrine strongly and reversibly activated most NAm neurons regardless of their basal firing rate. Epinephrine was more potent than norepinephrine, and this activation largely depends on α1-adrenoceptors. Interestingly, adrenergic activation of NAm neurons does not require an ionotropic synaptic mechanism, since postsynaptic excitatory or inhibitory receptor blockade did not occlude the excitatory effect, and bath-applied adrenergic agonists did not alter excitatory or inhibitory synaptic transmission. Instead, adrenergic agonists significantly elevated intrinsic membrane excitability to facilitate generation of recurrent action potentials. T-type calcium current (ICaT) and hyperpolarization-activated current (Ih) are involved in this excitation pattern, while not required for spontaneous AP induction by epinephrine. In contrast, pharmacological blockade of persistent sodium current (INaP) significantly inhibited the adrenergic effects. Our results demonstrate that central adrenergic signaling enhances the intrinsic excitability of NAm neurons, and persistent sodium current is required for this effect. This central balancing mechanism may counteract excessive peripheral cardiac excitation during increased sympathetic tone.New & NoteworthyCardiac preganglionic cholinergic neurons in the Nucleus ambiguus (NAm) are responsible for slowing cardiac pacemaking. This study identified that adrenergic agonists can induce rhythmic action potentials in otherwise quiescent cholinergic NAm preganglionic neurons in brainstem slice preparation. The modulatory influence of adrenaline on central parasympathetic outflow may contribute to both physiological and deleterious cardiovascular regulation.
Intermediate filaments EXC-2 and IFA-4 Maintain Luminal Structure of the Tubular Excretory Canals inCaenorhabditis elegans
Authors: Al-Hashimi Hikmat I. , Hall David H. , Ackley Brian D. , Lundquist Erik A. , Buechner Matthew 
Published: March 2018

ABSTRACTThe excretory canals ofCaenorhabditis elegansare a model for understanding the maintenance of apical morphology in narrow single-celled tubes. Light and electron microscopy shows that mutants inexc-2start to form canals normally, but these swell to develop large fluid-filled cysts that lack a complete terminal web at the apical surface, and accumulate filamentous material in the canal lumen. Here, whole-genome sequencing and gene rescue show thatexc-2encodes intermediate filament protein IFC-2. EXC-2/IFC-2 protein, fluorescently tagged via CRISPR/Cas9, is located at the apical surface of the canals independently of other intermediate filament proteins. EXC-2 is also located in several other tissues, though the tagged isoforms are not seen in the larger intestinal tube. Tagged EXC-2 binds via pulldown to intermediate filament protein IFA-4, which is also shown to line the canal apical surface. Overexpression of either protein results in narrow but shortened canals. These results are consistent with a model whereby three intermediate filaments in the canals, EXC-2, IFA-4, and IFB-1, restrain swelling of narrow tubules in concert with actin filaments that guide the extension and direction of tubule outgrowth, while allowing the tube to bend as the animal moves.Article SummaryTheC. elegansexcretory canals form a useful model for understanding formation of narrow tubes.exc-2mutants start to form normal canals that then swell into fluid-filled cysts. We show thatexc-2encodes a large intermediate filament (IF) protein previously not thought to be located in the canals. EXC-2 is located at the apical (luminal) membrane, binds to another IF protein, and appears to be one of three IF proteins that form a flexible meshwork to maintain the thin canal diameter. This work provides a genetically useful model for understanding the interactions of IF proteins with other cytoskeletal elements to regulate tube size and growth.
Optogenetic reconstitution reveals that Dynein-Dynactin-NuMA clusters generate cortical spindle-pulling forces as a multi-arm ensemble
Authors: Okumura Masako , Natsume Toyoaki , Kanemaki Masato T. , Kiyomitsu Tomomi 
Published: March 2018

AbstractTo position the mitotic spindle within the cell, dynamic plus ends of astral microtubules are pulled by membrane-associated cortical force-generating machinery. However, in contrast to the chromosome-bound kinetochore structure, how the diffusion-prone cortical machinery is organized to generate large spindle-pulling forces remains poorly understood. Here, we develop a light-induced reconstitution system in human cells. We find that induced cortical targeting of NuMA, but not dynein, is sufficient for spindle pulling. This spindle-pulling activity requires dynein-dynactin recruitment/activation by NuMA’s N-terminal long arm, and NuMA’s direct microtubule-binding activities to achieve a multiplicity of microtubule interactions. Importantly, we demonstrate that cortical NuMA assembles specialized focal structures that cluster multiple force-generating modules to generate cooperative spindle-pulling forces. This clustering activity of NuMA is required for spindle positioning, but not for spindle-pole focusing. We propose that cortical Dynein-Dynactin-NuMA (DDN) clusters act as the core force-generating machinery that organizes a multi-arm ensemble reminiscent of the kinetochore.
Improving international attractiveness of higher education institutions based on text mining and sentiment analysis
Authors: Santos Carolina Leana , Rita Paulo , Guerreiro João 
Published: March 2018

PurposeThe increasing competition among higher education institutions (HEI) has led students to conduct a more in-depth analysis to choose where to study abroad. Since students are usually unable to visit each HEIs before making their decision, they are strongly influenced by what is written by former international students (IS) on the internet. HEIs also benefit from such information online. The purpose of this paper is to provide an understanding of the drivers of HEIs success online.Design/methodology/approachDue to the increasing amount of information published online, HEIs have to use automatic techniques to search for patterns instead of analysing such information manually. The present paper uses text mining (TM) and sentiment analysis (SA) to study online reviews of IS about their HEIs. The paper studied 1938 reviews from 65 different business schools with Association to Advance Collegiate Schools of Business accreditation.FindingsResults show that HEIs may become more attractive online if they financially support students cost of living, provide courses in English, and promote an international environment.Research limitations/implicationsDespite the use of a major platform with a broad number of reviews from students around the world, other sources focussed on other types of HEIs may have been used to reinforce the findings in the current paper.Originality/valueThe study pioneers the use of TM and SA to highlight topics and sentiments mentioned in online reviews by students attending HEIs, clarifying how such opinions are correlated with satisfaction. Using such information, HEIs’ managers may focus their efforts on promoting international attractiveness of their institutions.
Higher education in state universities in Sri Lanka
Authors: Wickramasinghe Vathsala 
Published: March 2018

Purpose
The purpose of this paper is to review historical developments in higher education in Sri Lanka, and review issues faced and strategies adopted to improve higher education in state universities in the country. The paper also reviews national and international forces that influenced to modernise and improve higher education in state universities in the country.

Design/methodology/approach
The paper reviews available published documents from the last two decades to present and discuss key national and international forces transforming the higher education of the country and strategies adopted to modernise and improve higher education in state universities in the country.

Findings
Historical development in general and higher education together with key characteristics of the Sri Lankan education system are discussed. The governing bodies of the state university education, donor agencies and strategies adopted for the development of higher education in the country during the recent history have been reviewed. Conclusions and challenges for the future are also presented.

Originality/value
The higher education of the country underwent rapid transformations over the past seven decades with the aim of strengthening the wider relationship between university, industry and society. A review on higher education in Sri Lanka could provide lessons valuable for academics and practitioners alike worldwide.
A coupled thermal-drop impact analysis-based safety assessment of radioactive material cask
Authors: Liu Qiang , Zhu Shun-Peng , Yu Zheng-Yong , Ding Ran 
Published: March 2018

Purpose
Transport is an integral part of the nuclear fuel cycle. The procedures employed are designed and conducted to ensure the public and environment protection both routinely and when transport accidents occur. According to this, the purpose of this paper is to focus on a coupled thermal-drop impact analysis-based safety assessment of a nuclear fuel cask.

Design/methodology/approach
For the cask, high altitude falling and fire accidents are the two most serious accidents during its transportation. In this paper, a sequentially coupled thermal-drop impact analysis is performed by using a nuclear fuel cask model for safety assessment. High altitude falling and fire accidents of the nuclear fuel cask were conducted by using finite element simulations for coupled thermal-drop impact analysis.

Findings
Results showed that the cask can withstand a drop test and survive a fire of 800°C for 30 minutes. In addition, an improved design is explored and evaluated, which provides a reference for structural design and safety assessment of nuclear fuel casks.

Originality/value
A coupled thermal-drop impact analysis-based safety assessment procedure is developed for the nuclear fuel cask.
Critical reliability slip surface in soil slope stability analysis using Monte Carlo simulation method
Authors: Seyyed Alangi Seyyed Hossein , Nozhati Saeed , Vazirizade Seyyed Mohsen 
Published: March 2018

Purpose
Due to many different types of aleatory and epistemic uncertainty in soil properties, safety factor, which is assessed by deterministic analysis, is not reliable. The purpose of this paper is to determine the difference between critical slip surface in deterministic analysis and critical reliability slip surface in probabilistic analysis.

Design/methodology/approach
Deterministic analysis is formulated by the limit equilibrium methods, including Fellenius method, Bishop method, and Janbu’s simplified method. Then, the factor of safety is calculated for different slip surfaces. The stability of the soil is defined as the critical slip surface with the lowest factor of safety in each method. For probabilistic analysis, the value of reliability index, factor of safety, and probability of failure regarding given potential slip surface are considered as the stability index and obtained by the Monte Carlo simulation method.

Findings
To compare deterministic and probabilistic analysis as well as the influence of each of the aforementioned methods and stability index, a soil slope with three uncertainty parameters is analyzed and the results indicate that the critical slip surface is significantly different from critical reliability slip; however, the results from the above-mentioned methods are very close.

Research limitations/implications
There are many other methods that could be studied; however, the most usual ones were employed. Furthermore, this study just consider the most important factors as the uncertainty parameters; nevertheless, it can be extended to more geotechnical parameters.

Originality/value
Although there are many studies in this field, the authors conduct a succinct but very noteworthy research to show the difference between the results of mentioned methods as well as deterministic and probabilistic approaches and their influence on slip surface.
The consequences of audit committee quality
Authors: Lin Yu-Chun 
Published: March 2018

Purpose
This study aims to examine the consequences when audit committees have different economic incentives (i.e. incentive-based compensation) to switch auditors.

Design/methodology/approach
The author focuses on companies experiencing an auditor switching event (client-initiated dismissals) and uses Heckman’s (1997) two-stage estimation procedure to control endogenous bias. Audit committee quality is measured by the level of incentive-based compensation. Accrual quality and abnormal audit fees are examined over the periods of auditor switches.

Findings
Using 1,087 US companies between 2006 and 2014, the author found that audit committees’ incentive-based compensation is negatively (positively) associated with accruals quality (abnormal audit fees) only when companies switch from Big 4 to non-Big 4 auditors or switch within non-Big 4 auditors. For companies that switch from non-Big 4 to Big 4 auditors, she found no evidence.

Research limitations/implications
This study provides a detailed discussion of the consequences of audit committee quality. The findings also contribute to the literature by concluding that economic incentives are associated with ineffective oversight, particularly after auditor switches.

Practical implications
Sarbanes–Oxley Act and its associated regulations significantly expanded the oversight role of audit committees. However, regulators bypassed restrictions on audit committee compensation. Accordingly, the author suggests that regulators focus on the issue of economic incentives to improve audit committee quality.

Originality/value
Minimal research has been conducted on the role of audit committees when companies switch to a new external auditor. The author shows that when companies switch auditors, incentive-based compensation significantly affects the monitoring quality of audit committees.
The role of internal audit and user training in information security policy compliance
Authors: Stafford Thomas , Deitz George , Li Yaojie 
Published: March 2018

Purpose
The purpose of the study is to investigate the role of information security policy compliance and the role of information systems auditing in identifying non-compliance in the workplace, with specific focus on the role of non-malicious insiders who unknowingly or innocuously thwart corporate information security (IS) directives by engaging in unsafe computing practices. The ameliorative effects of auditor-identified training and motivational programs to emphasize pro-security behaviors are explored.

Design/methodology/approach
This study applies qualitative case analysis of technology user security perceptions combined with interpretive analysis of depth interviews with auditors to examine and explain the rubrics of non-malicious technology user behaviors in violation of cybersecurity directives, to determine the ways in which auditors can best assist management in overcoming the problems associated with security complacency among users.

Findings
Enterprise risk management benefits from audits that identify technology users who either feel invulnerable to cyber threats and exploits or feel that workplace exigencies augur for expedient workarounds of formal cybersecurity policies.

Research limitations/implications
Implications for consideration of CyberComplacency and Cybersecurity Loafing expand the insider threat perspective beyond the traditional malicious insider perspective.

Practical implications
Implications for consideration of CyberComplacency and Cybersecurity Loafing include broadened perspectives for the consultative role of IS audit in the firm.

Social implications
CyberComplacency is a practice that has great potential for harm in all walks of life. A better understanding of these potential harms is beneficial.

Originality/value
This study is the first to characterize CyberComplacency as computer users who feel they operate invulnerable platforms and are subsequently motivated to engage in less cybersecurity diligence than the company would desire. This study is also the first to characterize the notion of Cybersecurity Loafing to describe technically competent workers who take unauthorized but expedient steps around certain security polices in the name of workgroup efficiency.
Additive manufacturing of laser cutting nozzles by SLM: processing, finishing and functional characterization
Authors: Anilli Marco , Demir Ali Gökhan , Previtali Barbara 
Published: March 2018

Purpose
The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a whole production chain composed of an additive manufacturing (AM) and consecutive finishing processes together. Beyond the metrological and flow-related characterization of the produced nozzles, functional analysis on the use of the produced nozzles are carried out through laser cutting experiments.

Design/methodology/approach
SLM experiments were carried out to determine the correct compensation factor to achieve a desired nozzle diameter on steel with known processibility by SLM and using standard nozzle geometries for comparative purposes. The produced nozzles are finished through electrochemical machining (ECM) and abrasive flow machining (AFM). The performance of nozzles produced via additive manufacturing (AM) are compared to conventional ones on an industrial laser cutting system through cutting experiments with a 6 kW fibre laser. The produced nozzles are characterized in terms of pressure drop and flow dynamics through Schlieren imaging.

Findings
The manufacturing chain was regulated to achieve 1 mm diameter nozzles after consecutive post processing. The average surface roughness could be lowered by approximately 80 per cent. The SLM produced single chamber nozzles would perform similarly to conventional nozzles during the laser cutting of 1 mm mild steel with nitrogen. The double chamber nozzles could provide complete cuts with oxygen on 5 mm-thick mild steel only after post-processing. Post-processing operations proved to decrease the pressure drop of the nozzles. Schlieren images showed jet constriction at the nozzle outlet on the as-built nozzles.

Originality/value
In this work, the use of an additive manufacturing process is assessed together with suitable finishing and functional analysis of the related application to provide a complete production and evaluation chain. The results show how the finishing processes should be allocated in an AM-based production chain in a broader vision. In particular, the results confirm the functionality for designing more complex nozzle geometries for laser cutting, exploiting the flexibility of SLM process.
Development of productivity estimation model for mass-customized production by selective laser melting
Authors: Kostevsek Urska , Brajlih Tomaz , Balic Joze , Kadivnik Žiga , Drstvensek Igor 
Published: March 2018

Purpose
Fixed structures in prosthetic dentistry are highly customized products, manufactured individually for patients who have missing teeth. When choosing the technology for fixed dental structure manufacturing, three viable options are available (precise casting, milling and selective laser melting [SLM]). All these technologies can be used to produce a dental structure from CoCr alloy. Besides materials and availability of technologies, economic efficiency is an important factor when choosing a production method. The purpose of this study is to develop an estimation model for achievable productivity of selective laser melting and compare the results with the productivity of conventional manufacturing.

Design/methodology/approach
Results presented in this paper are based on manufacturing time analysis of an individual case with each of the technologies mentioned above. Because of the efficiency of SLM is highly dependent on how efficiently the work space of the machine is used, this issue was also included in the research. Data used for research were acquired from practical use of each technology in dental applications.

Findings
Analysis of achievable SLM manufacturing speeds is based on the previous research into manufacturing speeds of additive manufacturing technologies. The presented results present a model that can be used to estimate the productivity of the SLM technology.

Research limitations/implications
Research was limited to a specific SLM machine type with a fixed workspace volume. Nevertheless, the results show that any SLM machine has to be used as efficiently as possible to be able to be competitive regarding the conventional manufacturing technologies.

Practical implications
The presented results show clearly at least a rough estimation of what kind of parts and in what volume will be manufactured with an SLM machine prior to buying one.

Social implications
Results can help to widen the economically efficient way of running SLM machines, replacing conventional manufacturing for medical applications especially with complicated cases.

Originality/value
A method is presented to adapt the estimation model to a particular real-life production scenario. This method can be used to establish how efficiently selective laser sintering can be used and if using SLM machine instead of conventional manufacturing would be economically viable.