bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparing miRNA structure of mirtrons and non-mirtrons
Authors: Titov Igor I. , Vorozheykin Pavel S. 
Published: November 2017

AbstractBackgroundMicroRNAs proceeds through the different canonical and non-canonical pathways; the most frequent of the non-canonical ones is the splicing-dependent biogenesis of mirtrons. We compare the mirtrons and non-mirtrons of human and mouse to explore how their maturation appears in the precursor structure around the miRNA.ResultsWe found the coherence of the overhang lengths what indicates the dependence between the cleavage sites. To explain this dependence we suggest the 2-lever model of the Dicer structure that couples the imprecisions in Drosha and Dicer. Considering the secondary structure of all animal pre-miRNAs we confirmed that single-stranded nucleotides tend to be located near the miRNA boundaries and in its center and are characterized by a higher mutation rate. The 5′ end of the canonical 5′ miRNA approaches the nearest single-stranded nucleotides what suggests the extension of the loop-counting rule from the Dicer to the Drosha cleavage site. A typical structure of the annotated mirtron pre-miRNAs differs from the canonical pre-miRNA structure and possesses the 1- and 2nt hanging ends at the hairpin base. Together with the excessive variability of the mirtron Dicer cleavage site (that could be partially explained by guanine at its ends inherited from splicing) this is one more evidence for the 2-lever model. In contrast with the canonical miRNAs the mirtrons have higher snp densities and their pre-miRNAs are inversely associated with diseases. Therefore we supported the view that mirtrons are under positive selection while canonical miRNAs are under negative one and we suggested that mirtrons are an intrinsic source of silencing variability which produces the disease-promoting variants. Finally, we considered the interference of the pre-miRNA structure and the U2snRNA:pre-mRNA basepairing. We analyzed the location of the branchpoints and found that mirtron structure tends to expose the branchpoint site what suggests that the mirtrons can readily evolve from occasional hairpins in the immediate neighbourhood of the 3′ splice site.ConclusionThe miRNA biogenesis manifests itself in the footprints of the secondary structure. Close inspection of these structural properties can help to uncover new pathways of miRNA biogenesis and to refine the known miRNA data, in particular, new non-canonical miRNAs may be predicted or the known miRNAs can be re-classified.
CDC20B is required for deuterosome-mediated centriole production in multiciliated cells
Authors: Revinski Diego R. , Zaragosi Laure-Emmanuelle , Boutin Camille , Ruiz-Garcia Sandra , Deprez Marie , Thomé Virginie , Rosnet Olivier , Gay Anne-Sophie , Mercey Olivier , Paquet Agnès , Pons Nicolas , Ponzio Gilles , Marcet Brice , Kodjabachian Laurent , Barbry Pascal 
Published: November 2017

AbstractMulticiliated cells (MCCs) harbour dozens to hundreds of motile cilia, which beat in a synchronized and directional manner, thus generating hydrodynamic forces important in animal physiology. In vertebrates, MCC differentiation critically depends on the synthesis and release of numerous centrioles by specialized structures called deuterosomes. Little is known about the composition, organization and regulation of deuterosomes. Here, single-cell RNA sequencing reveals that human deuterosome-stage MCCs are characterized by the expression of many cell cycle-related genes. We further investigated the uncharacterized vertebrate-specificcell division cycle 20B(CDC20B) gene, the host gene of microRNA-449abc. We show that the CDC20B protein associates to deuterosomes and is required for the release of centrioles and the subsequent production of cilia in mouse andXenopusMCCs. CDC20B interacts with PLK1, which has been shown to coordinate centriole disengagement with the protease Separase in mitotic cells. Strikingly, over-expression of Separase rescued centriole disengagement and cilia production in CDC20B-deficient MCCs. This work reveals the shaping of a new biological function, deuterosome-mediated centriole production in vertebrate MCCs, by adaptation of canonical and recently evolved cell cycle-related molecules.
Detecting pathogen exposure during the non-symptomatic incubation period using physiological data
Authors: Milechin Lauren , Davis Shakti , Patel Tejash , Hernandez Mark , Ciccarelli Greg , Schwartz Steven , Samsi Siddharth , Hensley Lisa , Goff Arthur , Trefry John , Johnston Sara , Purcell Bret , Cabrera Catherine , Fleischman Jack , Reuther Albert , Rossi Franco , Honko Anna , Pratt William , Swiston Albert 
Published: November 2017

AbstractEarly pathogen exposure detection allows better patient care and faster implementation of public health measures (patient isolation, contact tracing). Existing exposure detection most frequently relies on overt clinical symptoms, namely fever, during the infectious prodromal period. We have developed a robust machine learning based method to better detect asymptomatic states during the incubation period using subtle, sub-clinical physiological markers. Starting with high-resolution physiological waveform data from non-human primate studies of viral (Ebola, Marburg, Lassa, and Nipah viruses) and bacterial (Y. pestis) exposure, we processed the data to reduce short-term variability and normalize diurnal variations, then provided these to a supervised random forest classification algorithm and post-classifier declaration logic step to reduce false alarms. In most subjects detection is achieved well before the onset of fever; subject cross-validation across exposure studies (varying viruses, exposure routes, animal species, and target dose) lead to 51h mean early detection (at 0.93 area under the receiver-operating characteristic curve [AUCROC]). Evaluating the algorithm against entirely independent datasets for Lassa, Nipah, andY. pestisexposures un-used in algorithm training and development yields a mean 51h early warning time (at AUCROC=0.95). We discuss which physiological indicators are most informative for early detection and options for extending this capability to limited datasets such as those available from wearable, non-invasive, ECG-based sensors.
LINE-2 transposable elements are a source for functional human microRNAs and target sites
Authors: Petri Rebecca , Brattås Per Ludvik , Sharma Yogita , Jönsson Marie E , Pircs Karolina , Bengzon Johan , Jakobsson Johan 
Published: November 2017

AbstractTransposable elements (TEs) are dynamically expressed at high levels in multiple human tissues, but the function of TE-derived transcripts remains largely unknown. In this study, we identify numerous TE-derived microRNAs (miRNAs) by conducting Argonaute2 RNA Immunoprecipitation followed by small RNA sequencing (AGO2 RIP-seq) on human brain tissue. Many of these miRNAs originated from LINE-2 (L2) elements, which entered the human genome around 100-300 million years ago. We found that L2-miRNAs derive from the 3’ end of the L2 consensus sequence and thus share very similar sequences, indicating that they could target transcripts with L2s in their 3’UTR. In line with this, we found that many protein-coding genes carry fragments of L2-derived sequences in their 3’UTR, which serve as target sites for L2-miRNAs. L2-miRNAs and targets were generally ubiquitously expressed at low levels in multiple human tissues, suggesting a role for this network in buffering transcriptional levels of housekeeping genes. Interestingly, we also found evidence that this network is perturbed in glioblastoma. In summary, our findings uncover a TE-based post-transcriptional network that shapes transcriptional regulation in human cells.
A new optimal design of surface mounted permanent magnet synchronous motors with integral slot per pole
Authors: Rezaeealam Behrooz , Rezaee-Alam Farhad 
Published: November 2017

Purpose
The purpose of this paper is to present a new optimal design for integral slot permanent magnet synchronous motors (PMSMs) to shape the air-gap magnetic field in sinusoidal and to reduce the cogging torque, simultaneously.

Design/methodology/approach
For obtaining this new optimal design, the influence of different magnetizations of permanent magnets (PMs), including radial, parallel and halbach magnetization is investigated on the performance of one typical PMSM by using the conformal mapping (CM) method. To reduce the cogging torque even more, the technique of slot opening shift is also implemented on the stator slots of analyzed PMSM without reduction in the main performance, including the air-gap magnetic field, the average torque and back-electromotive force (back-EMF).

Findings
Finally, an optimal configuration including the Hat-type magnet poles with halbach magnetization on the rotor and shifted slot openings on the stator is obtained through the CM method, which shows the main reduction in cogging torque and the harmonic content of air-gap magnetic field.

Practical implications
The obtained optimal design is completely practical and is validated by comparing with the corresponding results obtained through finite element method.

Originality/value
This paper presents a new optimal design for integral slot PMSMs, which can include different design considerations, such as the reduction of cogging torque and the total harmonic distortion of air-gap magnetic field by using the CM method.
Impact of PWM control frequency on efficiency of drive with 1 kW permanent magnet synchronous motor
Authors: Rudnicki Tomasz , Sikora Andrzej , Czerwinski Robert , Glinka Tadeusz 
Published: November 2017

Purpose
This paper aims to present the impact of Pulse Width Modulation (PWM) control frequency for specific Permanent Magnet Synchronous Motors (PMSMs) on the efficiency of the entire driving unit. Examinations were carried out for a PMSM unit with a power of 1 kW, rated speed of 1,000 rpm, and rated torque of 6 Nm.

Design/methodology/approach
The PWM frequency ranged from 4 to 20 kHz with increments of 1 kHz. Measurements were taken for each of the foregoing frequencies, for the different load torques, and for the different rotation speeds including overspeed. The results achieved allow the PWM control frequency to be properly adjusted for each PMSM to operate the entire driving unit in the most efficient way and, in consequence, save energy consumed by the drive.

Findings
Obtained results may be used as a kind of background for the design of drive system.

Research limitations/implications
For a specific PMSM-based drive system, one can find the optimal PWM control frequency. This frequency depends on the rotation speed and torque of the motor. However, the validity of the results presented in the paper is limited. They are valid for the specific motor drive under test and cannot be generalized easily.

Originality/value
This work shows that there is some maximal efficiency of the entire system depending on the rotation speed, load torque and switching frequency of the power transistors. For a specific motor working in a certain condition, we can find the minimum power loss.
Real-time implementation of discrete Fourier transform phase analysis and fault tolerant control for PMSM in electric vehicles
Authors: Abassi Moez , Khlaief Omar , Saadaoui Oussama , Chaari Abdelkader , Boussak Mohamed 
Published: November 2017

Purpose
Electric vehicles (EVs) require uninterrupted and safe conditions during operations. Therefore, the diagnostic of power devices and electric motor faults are needed to improve the availability of the system. Hence, fault-tolerant control (FTC), which combines switch fault detection, hardware redundancy and post-fault control, is used. This paper aims to propose an accurate open-phase fault detection and FTC of a direct torque control permanent magnet synchronous motor electrical vehicles by using discrete Fourier-transform phase method.

Design/methodology/approach
The main idea is to propose detection and identification of open-phase fault (faulty leg) among three phases voltage source invertor (VSI)-fed permanent magnet synchronous motor drives. Once the faulty leg is detected and isolated, a redundant phase leg insertion, shared by a three-phase VSI, is done by using independent bidirectional TRIAC switches to conduct FTC system. This accurate fault detection significantly improves system availability and reliability. The proposed method of open-phase fault detection and identification is based only on stator phase current measurement.

Findings
A novel method is proposed with experimental validation for fault detection, isolation and FTC for a three-phase VSI-fed permanent magnet synchronous motor.

Originality/value
The novel discrete Fourier-transform phase method is proposed to detect an open phase based on the measurement in real time of the instantaneous phase of stator current components in the stationary frame. The experimental implementation is carried out on powerful dSpace DS1104 controller board based on the digital signal processor TMS320F240. The validity of the proposed method has been experimentally verified.
Small-signal parameter extraction of asymmetric DCDMG AlGaN/GaN HEMT
Authors: Yadav Rahis Kumar , Pathak Pankaj , Mehra R.M. 
Published: November 2017

Purpose
This paper aims to report small-signal parameter extraction and simulation of enhanced dual-channel dual-material gate AlGaN/GaN high electron mobility transistor (HEMT) for the first time for the characterization of a device in microwave range of frequency.

Design/methodology/approach
For parameter extraction, a standard and well-known direct parameter extraction methodology is applied. Extrinsic elements of small-signal circuit model are extracted from measured S-parameters obtained using pinch-off cold field effect transistor (FET) biasing in the first step at a low frequency range and at a higher frequency range in the second step to ensure higher extraction accuracy. Intrinsic elements are extracted from intrinsic Y-parameters that are obtained after de-embedding all the extrinsic parasitic elements of the device. Figure of merits of radio frequency are also derived from the measured results and S-parameters of the proposed device.

Findings
Small signal parameters of the proposed device circuit model are extracted using the standard direct parameter extraction technique. Analysis of microwave figure of merits for device include maximum oscillation frequency, cut-off frequency, current gain, transducer power gain, available power gain, maximum stable gain, transconductance, drain conductance, stern stability factor and time delay.

Practical implications
The paper bridges the gaps between theory and experimental practices by validating extracted results with reported results of structurally matching devices.

Originality/value
An enhanced device structure investigated for small signal parameters incorporates field plate over dual metal engineered gate to provide better electric field uniformity, effective suppression of short channel effect, reduction in current collapse, improvement in carrier transport efficiency and enhancement in drain current capabilities.
Dynamic and steady state modeling of permanent magnet induction machine
Authors: Izadfar Hamid Reza , Naseri Hamid 
Published: November 2017

Purpose
Modeling electric machines is one of the powerful approaches for analyzing their performance. A dynamic model and a steady-state model are introduced for each electric machine. Permanent magnet induction machine (PMIM) is a dual-rotor electric machine, which has various advantages such as high-power factor and low magnetizing current. Studying PMIM and its modeling might be valuable. The purpose of this paper is to introduce a simple and accurate method for dynamic and steady-state modeling of PMIM.

Design/methodology/approach
In this paper, arbitrary dqo reference frame is used to model PMIM. First, three-phase dynamic equations of stator and rotors are introduced. Then, they are transferred to an arbitrary reference frame. The voltage and magnetic flux equations aligned at dqo axes are obtained. These equations give the dynamic model. To investigate the results, PMIM simulation is performed according to obtained dynamic equations. Simulation results verify the analytic calculations.

Findings
In this paper, dynamic equations of PMIM are obtained. These equations are used to determine dynamic equivalent circuits of PMIM. Steady-state equations and one phase equivalent circuit of the PMIM using phasor relations are also extracted.

Originality/value
PMIM equations along dqo axes and their dynamic and steady-state equivalent circuits are determined. These equations and the equivalent circuits can be transformed to different reference frames and analyzed easily.
Time-domain modelling of interconnects with highly oscillatory sources
Authors: Condon Marissa , Iserles Arieh 
Published: November 2017

Purpose
This paper aims to explore a new approach for time-domain modelling of interconnects with highly oscillatory modulated sources.

Design/methodology/approach
The paper uses an asymptotic method in conjunction with the Green’s function of the telegrapher’s equations. The Green’s function is expressed as a series of rational functions in the Laplace domain and are converted to pole-residue form, thereby enabling time-domain implementation.

Findings
The results indicate that the method is accurate for modelling interconnects when wide-varying frequencies are present in the sources.

Originality/value
The technique is important in circuit design for assessing signal integrity and in electromagnetic compatibility testing.
Influence factors to affect eddy current loss of damper winding in 24 MW bulb tubular turbine generator
Authors: Qiu Hongbo , Fan Xiaobin , Feng Jianqin , Yang Cunxiang 
Published: November 2017

Purpose
The purpose of this study is to find out the influence degree of harmonic current on the generator operating parameters. In practical operation of the salient-pole synchronous generator, the heat generated by eddy current loss may lead to the breaking of damper winding, and the damper winding is a key component for ensuring the reliable operation of generators. Therefore, it is important to study the distribution characteristics and the influence factors of eddy current loss. Taking a 24-MW bulb tubular turbine generator as a reference, the influence factors that affect the eddy current loss of damper winding are analyzed.

Design/methodology/approach
A two-dimensional (2-D) electromagnetic field model of the generator is established, and the correctness of the model is verified by comparing simulation results and experiment data. The eddy current losses of damper winding in various conditions are calculated by using the finite element method.

Findings
It is identified that the cogging effect, pole shoe magnetic saturation degree, pole arc coefficient and armature reaction are the main factors that affect the eddy current loss of the generator rotor. When the generator is installed with magnetic slot wedges, the distribution characteristic of eddy current loss is obtained through the study of the eddy current density distributions in the damper bars. The variations of eddy current losses with time are gained when the generator has different permeability slot wedges, pole arc coefficients and pole shoe magnetic saturation degrees.

Practical implications
The study of this paper provides a theoretical reference for the design and optimization of bulb tubular turbine generator structure.

Originality/value
The research can help enhance the understanding of eddy current distribution characteristics and influence factors of eddy current loss in bulb tubular turbine generator.
Too little, too late? Role of credit rating agencies in the Amtek AUTO default
Authors: Thukral Shagun , Korivi Sunder , Sharma Dipasha , Krishnakumar Dipali 
Published: November 2017

Subject area
Fixed Income markets, Financial Markets and Institutions.

Study level/applicability
This case can be used in a postgraduate finance course such as an MBA and executive program for courses such as Fixed Income Markets and Financial Markets and Institutions.

Case overview
In late August 2015, the sudden downgrade and eventual default of Amtek AUTO Ltd (Amtek) on its debentures upset mutual fund investors and regulators. Questions were raised about the credit rating agencies and their lack of timely action as well as about the independent credit analysis followed by fund houses to protect the interests of investors. One such investor, Suresh Nair, decided to gather all possible available information on Amtek to determine whether it was sheer negligence on the part of all parties involved or if Amtek was in fact in a situation of sudden distress. The case seeks to highlight the credit analysis process, while looking out for red flags to identify potential default or financial stress in a company.

Expected learning outcomes
To understand the credit analysis process through a fundamental analysis process. To analyze and interpret the financial position of the company through various financial ratios. Identifying “red flags” while evaluating a potential credit that pose as “risks” to credit assessment. Understanding the role and relevance of credit rating agencies in the bond market.

Supplementary materials
Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Subject code
CSS 1: Accounting and Finance
Teachers’ perspectives of a new food literacy curriculum in Australia
Authors: Nanayakkara Janandani , Margerison Claire , Worsley Anthony 
Published: November 2017

PurposeImplementation of a new food literacy curriculum provides multiple health and social benefits to school students. The success of any new curriculum execution is partly determined by teachers’ perceptions about the new curriculum contents, and barriers and challenges for its delivery. The purpose of this paper is to explore teachers’ views of a new food literacy curriculum named Victorian Certificate of Education Food Studies for senior secondary school students in Victoria, Australia.Design/methodology/approachA qualitative study design was used in this study. In total, 14 teachers who were planning to teach the new curriculum were individually interviewed in October-December 2016. The interviews were transcribed and analysed using the template analysis technique.FindingsThe majority of teachers appreciated the inclusion of food literacy and nutrition concepts in the new curriculum. However, half of the teachers had doubts about their readiness to teach it. Most teachers mentioned that they needed more training and resources to increase their confidence in teaching the curriculum.Practical implicationsThese findings reveal that teachers need more awareness, resources, and guidance to increase their confidence in delivering the new curriculum. Provision of more resources and opportunities for training in food literacy concepts and instructional methods could facilitate its implementation.Originality/valueThese findings serve as an important first step to gain the perspectives of secondary school teachers’ opinions about the new curriculum. Moreover, these opinions and suggestions could inform the future design and implementation of similar food literacy curricula in Australia or elsewhere.