bluuebunny/crossref_metadata_2025 huggingface dataset:
Distributed containment control with predefined performance of high‐order multi‐agent systems with unknown heterogeneous non‐linearities
Authors: Yoo Sung Jin
Published: August 2015

This study presents a predefined performance design approach for the distributed containment control of heterogeneous non‐linear strict‐feedback systems with multiple dynamic leaders under a directed graph topology where the leaders are neighbours of only a subset of the followers. It is assumed that all followers’ non‐linearities unmatched in the control input are unknown. The performance bounds, which characterise the convergence rate and maximum overshoot of control errors, are incorporated into the control error vectors, in order to ensure the predefined transient and steady‐state performance of containment control errors. On the basis of these error vectors, the authors design a simple distributed containment control system without employing any function approximators to estimate unknown non‐linearities and calculating the repeated derivatives of virtual controllers. It is shown from Lyapunov stability theorem that all followers nearly converge to the dynamic convex hull spanned by the dynamic leaders and the containment control errors are preserved within certain given predefined bounds.
Robust trajectory tracking control of uncertain quadrotors without linear velocity measurements
Authors: Liu Hao , Li Danjun , Yu Yao , Zhong Yisheng
Published: August 2015

In this brief, robust trajectory tracking control problem for quadrotors is investigated to improve the tracking performance of the closed‐loop control system subject to parametric uncertainties, non‐linearity and coupling, unmodelled dynamics, and external disturbances. The vertical, lateral, longitudinal and yaw motions of the vehicle are required to be controlled along desired trajectories simultaneously. The proposed linear‐decentralised controller consists of three parts: an observer to estimate the linear velocities, which cannot be measured directly, a position controller to achieve the trajectory tracking and produce the desired references for the pitch and roll angles, and an attitude controller to stabilise the attitude angles. The robustness properties of the whole uncertain closed‐loop control system are proven. Experimental results are given to demonstrate the effectiveness of the proposed closed‐loop control system.
The evolution towards the rod-like axisymmetric structure for turbulent stress tensor
Authors: Li Yi
Published: August 2015

Modelling the turbulent stress tensor is a main task for both large eddy simulations and methods based on Reynolds averaged Navier-Stokes equations. The turbulent stress is known as the subgrid-scale stress in the former and the Reynolds stress in the latter. In this paper, we examine the observation that the stress tensor tends to evolve towards a rod-like axisymmetric configuration. This observation has been well documented for the subgrid-scale stress. However, for the Reynolds stress, the available data are still too limited to draw a definite conclusion. In the first part of the paper, we show that the tendency is also universal for the Reynolds stress by direct numerical simulations of decaying anisotropic turbulence. To show the universality, it is crucial to examine the decaying process from initial turbulent fields with a wide range of levels of anisotropy. Such initial fields are generated by a novel synthetic turbulence model based on the so-called constrained multi-turnover Lagrangian map. In the second part, we use the direct numerical simulation data to study the dynamical mechanisms of the evolution towards the rod-like structures. Among others, the analyses show that the nonlinear self-interaction term is the driving force of the process, and that the pressure tends to enhance the disk-like axisymmetric structure but overall tends to reduce the anisotropy of the stress tensor. The results shed light on the subtle difference between the pressure and the nonlinear self-interaction terms.
Thermally multiplexed polymerase chain reaction
Authors: Phaneuf Christopher R. , Pak Nikita , Saunders D. Curtis , Holst Gregory L. , Birjiniuk Joav , Nagpal Nikita , Culpepper Stephen , Popler Emily , Shane Andi L. , Jerris Robert , Forest Craig R.
Published: August 2015

Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously—each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel.
Affects of supercooled liquid state on the properties of the crystallized phase: Microscopic and spectroscopic observations in ZnO-crystallized glass-ceramics
Authors: Takahashi Yoshihiro , Kinoshita Mikio , Miyazaki Takamichi , Osada Minoru , Terakado Nobuaki , Fujiwara Takumi
Published: August 2015

We examined the crystallization and crystal growth of ZnO in the viscoelastic supercooled liquid (SCL) phase based on microscopic and spectroscopic observations. The resulting glass–ceramics exhibits complex ZnO dendrites that precede the formation of Zn-rich regions because of phase separation. Compressive stresses are concentrated at the interface of ZnO crystals and SCL phase, suggesting that the domains are subject to a resistance during ZnO crystal growth. Defects were detected in the crystallized ZnO and attributed to the suppression of smooth ordering of the Zn-rich regions in the SCL phase.
Heat generation above break-even from laser-induced fusion in ultra-dense deuterium
Authors: Holmlid Leif
Published: August 2015

Previous results from laser-induced processes in ultra-dense deuterium D(0) give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u−1. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu) cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NTC resistor during around 5000 laser shots per measured point. No heating in the apparatus or the gas feed is normally used. The fusion process is suboptimal relative to previously published studies by a factor of around 10. The small neutral particles HN(0) of ultra-dense hydrogen (size of a few pm) escape with a substantial fraction of the energy. Heat loss to the D2 gas (at <1 mbar pressure) is measured and compensated for under various conditions. Heat release of a few W is observed, at up to 50% higher energy than the total laser input thus a gain of 1.5. This is uniquely high for the use of deuterium as fusion fuel. With a slightly different setup, a thermal gain of 2 is reached, thus clearly above break-even for all neutronicity values possible. Also including the large kinetic energy which is directly measured for MeV particles leaving through a small opening gives a gain of 2.3. Taking into account the lower efficiency now due to the suboptimal fusion process, previous studies indicate a gain of at least 20 during long periods.
MicroRNA-7/NF-κB signaling regulatory feedback circuit regulates gastric carcinogenesis
Authors: Zhao Xiao-Di , Lu Yuan-Yuan , Guo Hao , Xie Hua-Hong , He Li-Jie , Shen Gao-Fei , Zhou Jin-Feng , Li Ting , Hu Si-Jun , Zhou Lin , Han Ya-Nan , Liang Shu-Li , Wang Xin , Wu Kai-Chun , Shi Yong-Quan , Nie Yong-Zhan , Fan Dai-Ming
Published: August 2015

MicroRNAs play essential roles in gene expression regulation during carcinogenesis. Here, we investigated the role of miR-7 and the mechanism by which it is dysregulated in gastric cancer (GC). We used genome-wide screenings and identified RELA and FOS as novel targets of miR-7. Overexpression of miR-7 repressed RELA and FOS expression and prevented GC cell proliferation and tumorigenesis. These effects were clinically relevant, as low miR-7 expression was correlated with high RELA and FOS expression and poor survival in GC patients. Intriguingly, we found that miR-7 indirectly regulated RELA activation by targeting the IκB kinase IKKε. Furthermore, IKKε and RELA can repress miR-7 transcription, which forms a feedback circuit between miR-7 and nuclear factor κB (NF-κB) signaling. Additionally, we demonstrate that down-regulation of miR-7 may occur as a result of the aberrant activation of NF-κB signaling by Helicobacter pylori infection. These findings suggest that miR-7 may serve as an important regulator in GC development and progression.
SUSY-QCD Effects in Top Quark Pair Production in Association with a Gluon at the ILC*
Authors: Zhang Yan-Ming , Liu Ning
Published: August 2015

Given the null results of searches for new physics at the LHC, we investigate the one-loop effects SUSY QCD in the process

e
+

e
-

→
t

t
¯

g

at the ILC in Minimal Supersymmetric Standard Model (MSSM). We find that the relative SUSY-QCD corrections to the cross section of

e
+

e
-

→
t

t
¯

g

can maximally reach 6.5%(3.2%) at the ILC with

s

=
1000

GeV when

m

t
¯

1

=
313.4

GeV and

m

g
¯

=
500

(

1500

)

GeV.
Role of Surface Energy Coefficients and Temperature in the Fusion Reactions Induced by Weakly Bound Projectiles
Authors: Gharaei R. , Ghodsi O.N.
Published: August 2015

A systematic study is provided to analyze the behaviors of the interaction potential and complete fusion cross section which are influenced by the effects of the surface energy coefficients γ and temperature T. Our framework is restricted to the proximity formalism for fusion reactions induced by weakly bound projectiles 6Li, 7Li and 9Be. The different surface energy coefficients (γ-MN76, γ-MN95, γ-MS00 and γ-PD03) are used to study the role of the parameter γ in the proximity potentials AW 95 and BW 91. Comparison of the theoretical and the experimental values of the barrier characteristics (barrier heights and its positions) indicates that the modified versions AW 95 (γ-MS00) and BW 91 (γ-MS00) give the least deviations for fusion barrier heights. Moreover, it is shown that the temperature-dependence improves the calculated barrier heights based on the potentials AW 95 and BW 91. In the present study, the analysis of the mentioned effects on the complete fusion cross sections has been also discussed for the systems of interest. The obtained results reveal that the above-modified versions provide a more accurate description for behavior of the complete fusion cross sections than the original potentials at above-barrier energies. It is demonstrated that the increase of the temperature T enhances the complete fusion suppression at this energy range.
Roles of Superthermal Electrons and Adiabatic Heavy Ions on Heavy-Ion-Acoustic Solitary and Shock Waves in a Multi-Component Plasma
Authors: Shah M.G. , Rahman M.M. , Hossen M.R. , Mamun A.A.
Published: August 2015

Heavy-ion-acoustic (HIA) waves in an unmagnetized collisionless plasma system comprising superthermal electrons, Boltzmann distributed light ions, and adiabatic positively charged inertial heavy ions have been investigated both numerically and analytically. The well-known reductive perturbation method has been used to derive the Korteweg-de Vries (K-dV) and Burgers (BG) equations. The parametric regimes for the existence of both the positive and negative solitary and shock waves have been obtained. The effects of adiabaticity of heavy ions and superthermality of electrons, which are found to notably modify the fundamental features (viz. polarity, amplitude, phase speed, etc.) of HIA solitary and shock waves, are precisely studied. The results of our theoretical investigation can be applicable to understand the characteristics and basic nonlinear structures of HIA waves both in space and laboratory plasma situations.
Diversity of Foliar Phytophthora Species on Rhododendron in Oregon Nurseries
Authors: Knaus B. J. , Fieland V. J. , Graham K. A. , Grünwald N. J.
Published: August 2015

The genus Phytophthora contains some of the most notorious plant pathogens affecting nursery crops. Given the recent emergence of the sudden oak death pathogen Phytophthora ramorum, particularly in association with Rhododendron spp., characterization of Phytophthora communities associated with this host in nursery environments is prudent. Many taxa may present symptoms similar to P. ramorum but we do not necessarily know their identity, frequency, and importance. Here, we present a survey of Phytophthora taxa observed from seven nurseries in the U.S. state of Oregon. Incidence and diversity of Phytophthora communities differed significantly among nurseries and among seasons within nursery. The taxa P. syringae and P. plurivora were widespread and detected at most of the nurseries sampled. Nine other taxa were also detected but were found either in a single nursery or were shared among only a few nurseries. Characterization of the Phytophthora communities present in nurseries is an important step toward understanding the ecology of these organisms as well as an aid to nursery managers in determining what risks may be present when symptomatic plants are observed. This study builds on an increasing literature, which characterizes Phytophthora community structure in nurseries.
Naturally segregating loci exhibit epistasis for fitness
Authors: Monnahan Patrick J. , Kelly John K.
Published: August 2015

The extent to which gene interaction or epistasis contributes to fitness variation
within
populations remains poorly understood, despite its importance to a myriad of evolutionary questions. Here, we report a multi-year field study estimating fitness of
Mimulus guttatus
genetic lines in which pairs of naturally segregating loci exist in an otherwise uniform background. An allele at QTL x5b—a locus originally mapped for its effect on flower size—positively affects survival if combined with one genotype at quantitative trait locus x10a (aa) but has negative effects when combined with the other genotypes (Aa and AA). The viability differences between genotypes parallel phenotypic differences for the time and node at which a plant flowers. Viability is negatively correlated with fecundity across genotypes, indicating antagonistic pleiotropy for fitness components. This trade-off reduces the genetic variance for total fitness relative to the individual fitness components and thus may serve to maintain variation. Additionally, we find that the effects of each locus and their interaction often vary with the environment.
Explosive instability and erupting flux tubes in a magnetized plasma
Authors: Cowley S. C. , Cowley B. , Henneberg S. A. , Wilson H. R.
Published: August 2015

The eruption of multiple flux tubes in a magnetized plasma is proposed as a mechanism for explosive release of energy in plasmas. A significant fraction of the linearly stable isolated flux tubes are shown to be metastable in a box model magnetized atmosphere in which ends of the field lines are embedded in conducting walls. The energy released by destabilizing such field lines can be a large proportion of the gravitational energy stored in the system. This energy can be released in a fast dynamical time.
Direct load monitoring of rolling bearing contacts using ultrasonic time of flight
Authors: Chen W. , Mills R. , Dwyer-Joyce R. S.
Published: August 2015

The load applied by each rolling element on a bearing raceway controls friction, wear and service life. It is possible to infer bearing load from load cells or strain gauges on the shaft or bearing housing. However, this is not always simply and uniquely related to the real load transmitted by rolling elements directly to the raceway. Firstly, the load sharing between rolling elements in the raceway is statically indeterminate, and secondly, in a machine with non-steady loading, the load path is complex and highly transient being subject to the dynamic behaviour of the transmission system. This study describes a method to measure the load transmitted directly by a rolling element to the raceway by using the time of flight (ToF) of a reflected ultrasonic pulse. A piezoelectric sensor was permanently bonded onto the bore surface of the inner raceway of a cylindrical roller bearing. The ToF of an ultrasonic pulse from the sensor to the roller–raceway contact was measured. This ToF depends on the speed of the wave and the thickness of the raceway. The speed of an ultrasonic wave changes with the state of the stress, known as the acoustoelastic effect. The thickness of the material varies when deflection occurs as the contacting surfaces are subjected to load. In addition, the contact stiffness changes the phase of the reflected signal and in simple peak-to-peak measurement, this appears as a change in the ToF. In this work, the Hilbert transform was used to remove this contact dependent phase shift. Experiments have been performed on both a model line contact and a single row cylindrical roller bearing from the planet gear of a wind turbine epicyclic gearbox. The change in ToF under different bearing loads was recorded and used to determine the deflection of the raceway. This was then related to the bearing load using a simple elastic contact model. Measured load from the ultrasonic reflection was compared with the applied bearing load with good agreement. The technique shows promise as an effective method for load monitoring in real-world bearing applications.
A variational viscosity-limit approach to the evolution of microstructures in finite crystal plasticity
Authors: Günther Christina , Junker Philipp , Hackl Klaus
Published: August 2015

A micromechanical model for finite single crystal plasticity was introduced by Kochmann & Hackl (2011
Contin. Mech. Thermodyn.
23, 63–85 (
doi:10.1007/s00161-010-0714-5
)). This model is based on thermodynamic variational principles and leads to a non-convex variational problem. Based on the Lagrange functional, an incremental strategy was outlined to model the time-continuous evolution of a first-order laminate microstructure. Although this model provides interesting results on the material point level, owing to the global minimization in the evolution equations, the calculation time and numerical instabilities may cause problems when applying this model to macroscopic specimens. In this paper, a smooth transition zone between the laminates is introduced to avoid global minimization, which makes the numerical calculations cumbersome compared with the model in Kochmann & Hackl. By introducing a smooth viscous transition zone, the dissipation potential and its numerical treatment have to be adapted. We outline rate-dependent time-evolution equations for the internal variables based on variational techniques and show as first examples single-slip shear and tension/compression tests.
The importance of mechanisms for the evolution of cooperation
Authors: van den Berg Pieter , Weissing Franz J.
Published: August 2015

Studies aimed at explaining the evolution of phenotypic traits have often solely focused on fitness considerations, ignoring underlying mechanisms. In recent years, there has been an increasing call for integrating mechanistic perspectives in evolutionary considerations, but it is not clear whether and how mechanisms affect the course and outcome of evolution. To study this, we compare four mechanistic implementations of two well-studied models for the evolution of cooperation, the Iterated Prisoner's Dilemma (IPD) game and the Iterated Snowdrift (ISD) game. Behavioural strategies are either implemented by a 1 : 1 genotype–phenotype mapping or by a simple neural network. Moreover, we consider two different scenarios for the effect of mutations. The same set of strategies is feasible in all four implementations, but the probability that a given strategy arises owing to mutation is largely dependent on the behavioural and genetic architecture. Our individual-based simulations show that this has major implications for the evolutionary outcome. In the ISD, different evolutionarily stable strategies are predominant in the four implementations, while in the IPD each implementation creates a characteristic dynamical pattern. As a consequence, the evolved average level of cooperation is also strongly dependent on the underlying mechanism. We argue that our findings are of general relevance for the evolution of social behaviour, pleading for the integration of a mechanistic perspective in models of social evolution.
The unrepresentative house
Authors: Ozarow Daniel
Published: August 2015

Purpose

– Argues that the British House of Commons is acutely unrepresentative of the population that it serves. A range of party leadership interventions that have sought to increase the possibilities for women and those from minority groups to become MPs are evaluated, but regulating in this way is found to have largely failed. Alternative policy solutions are proposed that seek to increase the “supply” of candidates from such backgrounds.

Design/methodology/approach

– Conducts document analysis of political parties’ equality and diversity policies and assesses their impact upon their proportion of MPs or parliamentary candidates from minority backgrounds.

Findings

– Argues that the real problem lies in the lack of engagement in the political process and a shortage of candidates from such backgrounds putting themselves forward for nomination in the first place. Thus, authentic parliamentary diversity cannot be created through enforcement but needs to be fostered organically through supportive longer-term measures alongside electoral reform.

Practical implications

– Advances the view that greater diversity is required for parliamentary legitimacy but top-down interventions have been counterproductive; barely improving the proportion of MPs from minority backgrounds and actually presenting threats to party autonomy and quality of democracy.

Social implications

– Shows how structural problems complicate the ease with which women and those from working-class, ethnic minority and disability backgrounds can engage with the political process and then successfully become parliamentary candidates. Reforming the political culture and targeted policies aimed at reversing the barriers to entry may create a more level playing field by encouraging them to stand.

Originality/value

– Offers a timely case study of the neglected and longstanding lack of representation in Parliament that is uniquely interrogated from an HRM perspective.
Diversity and inclusion depend on effective engagement
Authors: Sanyal Chandana , Wilson Doirean , Sweeney Charlotte , Smith Rachele Jude , Kaur Satwant , Yates Christine
Published: August 2015

Purpose

– Highlights some of the things that can be done to ensure that organizations embed diversity and inclusion.

Design/methodology/approach

– Considers the need for effective engagement, the importance of performance indicators for diversity and inclusion and the key role of sharing stories. Discusses, too, how critical race theory could help to bring about improvements.

Findings

– Advances the view that a transformational process that supports employees with the knowledge and sustainable skills needed to improve business performance via ethical means will form a significant part of future-proofing organizations.

Practical implications

– Argues that, to achieve this organizations have to drive home the message that diversity and inclusion are everyone’s business.

Social implications

– Advances the view that a unified approach to diversity and inclusion, which is embedded in the business ethics of the organization, can have a sustainable positive impact on the health and well-being of individuals, business and society.

Originality/value

– Considers diversity and inclusion from diverse perspectives and draws conclusions that can help organizations to perform better in these areas.
HR leaders hold the key to effective diversity management
Authors: Martins Lola-Peach
Published: August 2015

Purpose

– Observes that diversity management (DM) is central to the human resource management (HRM) function in work organizations, and the past decade has seen employers seeking to establish more devolved management structures that place more emphasis on local-level managerial decision-making.

Design/methodology/approach

– Argues that an important component of this shift in many organizations has been the reconfiguration of the role of first-line managerial leader (FLML) to encompass a wider range of HRM responsibilities. Hence, diversity management and leadership in this regard are a key HRM role for leaders and managers.

Findings

– Highlights case-study evidence to illustrate how far the success or otherwise of such a process of change is explicable in terms of the role played by four inter-related sets of factors which are key elements linked to organizational learning and strategic fit.

Practical implications

– Advances the view that organizations that wish to enhance the HRM/DM role and performance of FLMLs need to adopt a holistic strategic approach which encompasses organizational learning and FLML strategies.

Originality/value

– Demonstrates that organizations that use an integrated framework to help with the close co-ordination of business and HRM activities are likely to perform better as they engage in effective learning.
Three-dimensional cracked discs under anti-plane loading and effects of the boundary conditions
Authors: Berto Filippo , Campagnolo Alberto
Published: August 2015

Purpose

– Accordingly to the recent multi-scale model proposed by Sih and Tang, different orders of stress singularities are related to different material dependent boundary conditions associated with the interaction between the V-notch tip and the material under the remotely applied loading conditions. This induces complex three-dimensional stress and displacement fields in the proximity of the notch tip, which are worthy of investigation. The paper aims to discuss these issues.

Design/methodology/approach

– Starting from Sih and Tang’s model, in the present contribution the authors propose some analytical expressions for the calculation of the strain energy density (SED) averaged over a control volume embracing the V-notch tip. The expressions vary as a function of the different boundary conditions. Dealing with the specific crack case, the results from the analytical frame are compared with those determined numerically under linear-elastic hypotheses, by applying different constraints to the through-the-thickness crack edges in three-dimensional discs subjected to Mode III loading. Free-free and free-clamped cases are considered.

Findings

– Due to three-dimensional effects, the application of a nominal Mode III loading condition automatically provokes coupled Modes (I and II). Not only the intensity of the induced modes but also their degree of singularity depend on the applied conditions on the crack flanks. The variability of local SED through the thickness of the disc is analysed by numerical analyses and compared with the theoretical trend.

Originality/value

– The capability of the SED to capture the combined three-dimensional effects is discussed in detail showing that this parameter is particularly useful when the definition of the stress intensity factors (SIFs) is ambiguous or the direct comparison between SIFs with odd dimensionalities is not possible.
Formation of R & D alliances in the Chinese mobile telephony industry
Authors: Jin Jun , von Zedtwitz Max , Chong Li Choy
Published: August 2015

Purpose

– The purpose of this paper is to investigate how international R & D alliances are formed during industry transition from the point of view of the local Chinese partner.

Design/methodology/approach

– Review of industry data provided by Chinese Statistical Office coupled with four in-depth case studies.

Findings

– The nature of the technology, the characteristics of partners and the previous cooperation experience between partners are significantly related to the R & D alliance formation. The research also suggests that during this fast-growing transition period, Chinese local firms preferred non-equity contractual agreements over equity joint venture such as R & D alliance modes, and Chinese local firms favoured American and European multinational corporations (MNCs) as their alliance partners over MNCs from other countries, including the highly developed Japan and Korea.

Research limitations/implications

– Single-industry focus (telecommunications), and anonymization of cases because of confidentiality of case firms. Single-country focus (China).

Practical implications

– Firms in China and other emerging countries can improve their technological capability (TC) by choice to facilitate future alliance formation to access and learn the latest technology from their alliance partners, especially during the transition period of an industry and when mature and emerging technologies co-exist.

Originality/value

– This paper refines alliance theory by focusing on an industry in transition and analyses formation decision factors from the point of view of the smaller domestic partner – usually studies do not differentiate as to industry maturity and inequality between partners.
Entrepreneurial motivation and small business growth in Rwanda
Authors: Eijdenberg Emiel L , Paas Leonard J , Masurel Enno
Published: August 2015

Purpose

– The purpose of this study is to investigate the relationship between entrepreneurial motivation and small business growth in one of the poorest emerging countries: the African least developed country (LDC), Rwanda.

Design/methodology/approach

– On the basis of theoretical resources and a pre-study of interviews with local experts in Rwanda, the authors developed a survey for this study. Based on primary data from 133 Rwandan small business owners, the authors conducted an exploratory factorial analysis to uncover the underlying factors. Subsequently, the authors conducted regression analyses to test the hypotheses.

Findings

– The analyses show that the predictors for the growth of small businesses can be divided into three factors: one factor with a mix of motivations related to family background, necessity and opportunity motivations; one factor with items predominantly related to opportunity motivation; and one factor with items related to necessity motivation. The first factor has the strongest positive effect on small business growth followed by the second factor. The factor concerning necessity motivation was irrelevant for further inclusion in the regression model, due to insufficient reliability.

Research limitations/implications

– The study contributes to the debate in the literature about which entrepreneurial motivations affect the growth of small businesses in LDCs.

Practical implications

– The results reported in this study also have implications for how small business growth in LDCs can be supported and stimulated by policy-making practice.

Originality/value

– This study shows that entrepreneurial motivation is not a clear distinction between necessity and opportunity, but that a mix of motivations is important to assess the growth of small businesses in an LDC, which is an understudied context.
Genomic Resources Notes accepted 1 April 2015 – 31 May 2015
Authors:   Genomic Resources Development Consortium, Almeida‐Val Vera Maria Fonseca , Boscari E. , Coelho Maria Manuela , Congiu L. , Grapputo A. , Grosso Ana Rita , Jesus Tiago Filipe , Luebert Federico , Mansion Guilhem , Muller Ludo A. H. , Töre Demet , Vidotto M. , Zane L.
Published: August 2015

This article documents the public availability of transcriptomic resources for (i) the stellate sturgeon Acipenser stellatus, (ii) the flowering plant Campanula gentilis and (iii) two endemic Iberian fish, Squalius carolitertii and Squalius torgalensis.
National decline in invasive prenatal diagnostic procedures in association with uptake of combined first trimester and cell‐free DNA aneuploidy screening
Authors: Robson Stephen J. , Hui Lisa
Published: August 2015

In late 2012, a new screening test for fetal aneuploidy based on circulating cell‐free DNA (cfDNA) became available to Australian women. The introduction of this technology in the United States has led to a reduction in invasive diagnostic procedures. Analysis of the number of amniocentesis and chorionic villus sampling (CVS) procedures performed in Australia from 1994 to 2014 shows that the introduction of cfDNA testing has been associated with the most rapid decline in invasive procedures in the last 20 years. This change has important implications for training in, and maintenance of, the procedural skills of amniocentesis and CVS.
Genetic structure and relationships of 16 Asian and European cattle populations using DigiTag2 assay
Authors: Yonesaka Riku , Sasazaki Shinji , Yasue Hiroshi , Niwata Satoru , Inayoshi Yousuke , Mukai Fumio , Mannen Hideyuki
Published: August 2015

In this study, we genotyped 117 autosomal single nucleotide polymorphisms using a DigiTag2 assay to assess the genetic diversity, structure and relationships of 16 Eurasian cattle populations, including nine cattle breeds and seven native cattle. Phylogenetic and principal component analyses showed that Bos taurus and Bos indicus populations were clearly distinguished, whereas Japanese Shorthorn and Japanese Polled clustered with European populations. Furthermore, STRUCTURE analysis demonstrated the distinct separation between Bos taurus and Bos indicus (K=2), and between European and Asian populations (K=3). In addition, Japanese Holstein exhibited an admixture pattern with Asian and European cattle (K=3‐5). Mongolian (K=13‐16) and Japanese Black (K=14‐16) populations exhibited admixture patterns with different ancestries. Bos indicus populations exhibited a uniform genetic structure at K=2‐11, thereby suggesting that there are close genetic relationships among Bos indicus populations. However, the Bhutan and Bangladesh populations formed a cluster distinct from the other Bos indicus populations at K=12‐16. In conclusion, our study could sufficiently explain the genetic construction of Asian cattle populations, including: (i) the close genetic relationships among Bos indicus populations; (ii) the genetic influences of European breeds on Japanese breeds; (iii) the genetic admixture in Japanese Holstein, Mongolian and Japanese Black cattle; and (iv) the genetic subpopulations in Southeast Asia.
Is miR‐34a a Well‐equipped Swordsman to Conquer Temple of Molecular Oncology?
Authors: Farooqi Ammad Ahmad , Fayyaz Sundas , Shatynska‐Mytsyk Iryna , Javed Zeeshan , Jabeen Saima , Yaylim Ilhan , Gasparri Maria Luisa , Panici Pierluigi Benedetti
Published: August 2015

Overwhelmingly increasing advancements in miRNA biology have opened new avenues for pharmaceutical companies to initiate studies on designing effective, safe, and therapeutically active candidates using miRNA mimetics and miRNA inhibitors. In accordance with this approach, development of miravirsen and SPC3649, an LNA‐based (locked nucleic acid) antisense molecule against miR‐122, to treat hepatitis C has sparked interest in identifying most efficient microRNAs for journey from bench‐top toward pharmaceutical industry and breakthroughs in delivery technology will pave the way to ‘final frontier’. MRX34, a liposome‐formulated mimic of miR‐34 for treatment of metastatic cancer with liver involvement and unresectable primary liver cancer, has also entered in clinical trial. There is a successive increase in the research work related to miR‐34 biology and miRNA regulation of modulators of intracellular signaling cascades. We partition this review into how miR‐34a is regulated by different proteins and how Wnt‐ and TGF‐induced intracellular signaling cascades are modulated by miR‐34a. In this review, we bring to limelight how miR‐34a regulates its target genes to induce apoptosis and inhibit cell proliferation as evidenced by in vitro and in vivo analysis. We also discuss miR‐34 regulation of PDGFR and c‐MET and recent advancements in nanotechnologically delivered miR‐34a. Spotlight is also set on modulation of chemotherapeutic sensitivity by miR‐34a in cancer cells using reconstruction studies. Clinical trial of miR‐34 is indicative of its tremendous potential, and continuous cutting research will prove to be effective in efficiently translating laboratory findings into clinically effective therapeutics.
Analysis of Enoyl‐Acyl Carrier Protein Reductase Structure and Interactions Yields an Efficient Virtual Screening Approach and Suggests a Potential Allosteric Site
Authors: Ghattas Mohammad A. , Mansour Ramez A. , Atatreh Noor , Bryce Richard A.
Published: August 2015

Enoyl‐acyl carrier protein reductases have an important role in fatty acid biosynthesis and are considered essential for bacterial and protozoal survival. Here, we perform a computational assessment of enoyl‐acyl carrier protein reductase structures, providing insights for inhibitor design that we incorporate into a virtual screening approach. Firstly, we analyse 80 crystal structures of 16 different enoyl‐acyl carrier protein reductases for their active site characteristics and druggability, finding these sites contain a readily druggable pocket, of varying size and shape. Interestingly, a high affinity, potentially allosteric site was identified for pfFabI. Analysis of the ligand–protein interactions of four enoyl‐acyl carrier protein reductases from different micro‐organisms (InhA, pfFabI, saFabI and ecFabI), involving 59 available crystal structures, found three commonly shared interactions; constraining these interactions in docking improved enrichment of enoyl‐acyl carrier protein reductase virtual screens, by up to 60% in the top 3% of the ranked library. This docking protocol also improved pose prediction, decreasing the root‐mean‐square deviation to crystallographic pose by up to 75% on average. The binding site analysis and knowledge‐based docking protocol presented here can potentially assist in the structure‐based design of new enoyl‐acyl carrier protein reductase inhibitors.
Lesion Evaluation, Screening and Identification of Oral Neoplasia Study: an assessment of high‐risk Australian populations
Authors: Dost Fatima , Do Loc , Farah Camile S.
Published: August 2015

Objectives

Population‐based screening programmes which promote early detection are effective in reducing the burden of disease associated with chronic illness. The efficacy of screening for oral cancer and its preceding lesions appears promising in high‐risk groups. The objective of this study is to report on the recruitment experiences and outcomes of the ‘Lesion Evaluation, Screening and Identification of Oral Neoplasia Study’ programme, a multicentre oral mucosal screening programme developed in South East Queensland, Australia.

Methods

Ten screening sites were established within public and private dental clinics, indigenous health clinics and a community pharmacy. Risk assessment was undertaken through a semi‐structured interview and self‐directed questionnaires. Oral mucosal examination was completed by one of 11 trained and calibrated dentists or oral health therapists, under conventional operatory parameters.

Results

The study ran for 24 months from April 2012 to April 2014. A total of 1498 participants consented to oral mucosal screening, with complete data available for 1252 (83.6%). Almost half (n = 561; 44.8%) were from an area of high disadvantage, and 59.9% reported annual household incomes below $40K (n = 750). Participants from backgrounds experiencing the highest level of disadvantage were more likely to have a history of tobacco use (P = 0.04). Those participants with low income had significantly higher prevalence ratios (PRs) of having suspicious oral mucosal lesions (PR: 3.13 and 5.85, respectively) than the most advantageous. Examiners reported difficulties in recruitment, which stemmed mainly from patient refusal due to time constraints, disinterest or embarrassment relating to their oral condition. Clinician outreach also proved inefficient in participant recruitment.

Conclusions

Population‐based screening for oral cancer in the Australian context was effective in identifying people at risk of developing oral lesions, but participant recruitment appears to be a significant barrier to implementation. Further strategies are required to improve the success of such a programme, as we advocate for screening in high‐risk populations.
Bone repair of critical size defects treated with autogenic, allogenic, or xenogenic bone grafts alone or in combination with rhBMP‐2
Authors: Issa João Paulo , Gonzaga Miliane , Kotake Bruna Gabriela , de Lucia Conrado , Ervolino Edilson , Iyomasa Mamie
Published: August 2015

Objective

To evaluate the bone repair of critical size defects treated with autogenic, allogenic, or xenogenic bone grafts alone or in combination with rhBMP‐2.

Material and methods

In 112 rats, a critical bone defect of 5 mm bilaterally in the calvaria was made and filled with different bone grafts alone or combined with rhBMP‐2: group autograft (AuG); group allograft (AlG); group xenograft (XeG); group AuG/BMP‐2 (autograft and 5 μg rhBMP‐2); group AlG/BMP‐2 (allograft and 5 μg rhBMP‐2); group XeG/BMP‐2 (xenograft and 5 μg rhBMP‐2); group BMP‐2 (5 μg rhBMP‐2); and control group, filled only with blood coagulum. After a period of 4 or 6 weeks, the animals were euthanized. Histological and histometric analyses were performed for new bone formation (NB), as well as the immunohistochemical detection of tartrate‐resistant acid phosphatase (TRAP), and zymographic analysis (MMP) of type 2 and 9.

Results

Histological analysis showed the bone healing process was faster and favorable in AuG and AuG/BMP‐2. In both periods, the grafted groups (AuG, XeG and AlG) had a greater volume of NB than the control group, which was even greater when combined with rhBMP‐2. The XeG group showed a higher number of TRAP‐positive multinucleated osteoclasts, and enzymatic activity revealed different levels of proMMP‐2, MMP‐2, and MMP‐9 (6 weeks).

Conclusion

The different types of grafts increased bone formation, mainly associated with rhBMP‐2, enhancing and accelerating the repair process. These groups had higher enzymatic indices than the control group especially with XeG, which also showed higher TRAP‐positive multinucleated cells similar to osteoclasts, suggesting a remodeling process.
Increased ID4 expression, accompanied by mutant p53 accumulation and loss of BRCA1/2 proteins in triple‐negative breast cancer, adversely affects survival
Authors: Thike Aye A. , Tan Puay H. , Ikeda Murasaki , Iqbal Jabed
Published: August 2015

Aims

Breast cancer 1 (BRCA1) expression is down‐regulated in a significant proportion of non‐hereditary breast cancers, in the absence of any mutation. This phenomenon is more pronounced in oestrogen (ER)‐negative tumours. Recent studies have suggested that inhibitor of DNA binding 4 (ID4), as well as p53, participate in the transcriptional regulation of BRCA1.

Methods

Immunohistochemical expression of ID4, BRCA1, BRCA2 and p53 in 699 women with triple‐negative breast cancer was investigated using tissue microarrays. The prognostic role of these biomarkers was also evaluated. Survival outcomes were estimated with the Kaplan–Meier method and compared between groups with log‐rank statistics.

Results

Loss of BRCA1 and BRCA2 expression and overexpression of ID4 and p53 was observed in 75%, 90%, 95% and 66% of tumours, respectively. ID4 expression was increased in higher tumour grade (P < 0.001) and was associated significantly with basal‐like subtype (P < 0.001), BRCA2 down‐regulation (P = 0.037) and p53 accumulation (P < 0.001). Patients with strong ID4 expression displayed worse disease‐free survival in both triple‐negative breast cancers (P = 0.041) and basal‐like triple‐negative breast cancers (P = 0.026).

Conclusion

There is frequent ID4 expression and concomitant loss of BRCA proteins in triple‐negative breast cancer. We hypothesize that strong ID4 expression could be useful as a prognostic marker in triple‐negative breast cancer, predicting early tumour recurrence.
The phylogeography of the rodent genus Malacomys suggests multiple Afrotropical Pleistocene lowland forest refugia
Authors: Bohoussou Kouakou Hilaire , Cornette Raphael , Akpatou Bertin , Colyn Marc , Kerbis Peterhans Julian , Kennis Jan , Šumbera Radim , Verheyen Erik , N'Goran Eliézer , Katuala Pionus , Nicolas Violaine
Published: August 2015

Aim

This study aims to reconstruct the evolutionary history of the African rodent genus Malacomys and to identify factors driving diversification within this genus.

Location

African tropical lowland forest.

Methods

Analyses were based on sampling representatives from most of the known geographical range of the genus. We assessed genetic structure and historical biogeography using a combination of mitochondrial and nuclear markers. Morphological differences between lineages were analysed using a geometric morphometric approach.

Results

Three species of Malacomys are recognized within the genus. Two are endemic to West Africa, and one is endemic to Central Africa. Our analyses reveal a strong phylogeographical structure with 13 lineages, most of them allopatric or parapatric. A complex biogeographical history, including dispersal–vicariance events, explains the current genetic structure of Malacomys. Discrete divergence events within the genus are dated to the mid‐Pliocene (3.7 Ma, 95% range: 2.4–5.2 Ma) and the Pleistocene (less than 1.9 Ma, with most events less than 1 Ma). Morphological variation is partly congruent with genetic structure and may indicate local adaptations.

Main conclusions

Climatic oscillations, which led to periodic fragmentation of the forest habitat, seem to be the major driver of diversification within this genus. Our results support the existence of multiple small, rather than a few large, forest refugia during glacial maxima. Rivers have played a significant role in shaping boundaries of several regional haplogroups, either by promoting diversification or by preventing secondary contact between previously isolated lineages.