bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogenomic and Functional Analysis of Pterin-4a-Carbinolamine Dehydratase Family (COG2154) Proteins in Plants and Microorganisms
Authors: Naponelli Valeria , Noiriel Alexandre , Ziemak Michael J. , Beverley Stephen M. , Lye Lon-Fye , Plume Andrew M. , Botella José Ramon , Loizeau Karen , Ravanel Stéphane , Rébeillé Fabrice , de Crécy-Lagard Valérie , Hanson Andrew D. 
Published: February 2008

AbstractPterin-4a-carbinolamine dehydratases (PCDs) recycle oxidized pterin cofactors generated by aromatic amino acid hydroxylases (AAHs). PCDs are known biochemically only from animals and one bacterium, but PCD-like proteins (COG2154 in the Clusters of Orthologous Groups [COGs] database) are encoded by many plant and microbial genomes. Because these genomes often encode no AAH homologs, the annotation of their COG2154 proteins as PCDs is questionable. Moreover, some COG2154 proteins lack canonical residues that are catalytically important in mammalian PCDs. Diverse COG2154 proteins of plant, fungal, protistan, and prokaryotic origin were therefore tested for PCD activity by functional complementation in Escherichia coli, and the plant proteins were localized using green fluorescent protein fusions. Higher and lower plants proved to have two COG2154 proteins, a mitochondrial one with PCD activity and a noncanonical, plastidial one without. Phylogenetic analysis indicated that the latter is unique to plants and arose from the former early in the plant lineage. All 10 microbial COG2154 proteins tested had PCD activity; six of these came from genomes with no AAH, and six were noncanonical. The results suggested the motif [EDKH]-x(3)-H-[HN]-[PCS]-x(5,6)-[YWF]-x(9)-[HW]-x(8,15)-D as a signature for PCD activity. Organisms having a functional PCD but no AAH partner include angiosperms, yeast, and various prokaryotes. In these cases, PCD presumably has another function. An ancillary role in molybdopterin cofactor metabolism, hypothesized from phylogenomic evidence, was supported by demonstrating significantly lowered activities of two molybdoenzymes in Arabidopsis thaliana PCD knockout mutants. Besides this role, we propose that partnerless PCDs support the function of as yet unrecognized pterin-dependent enzymes.
Tomato Transcriptional Changes in Response toClavibacter michiganensissubsp.michiganensisReveal a Role for Ethylene in Disease Development
Authors: Balaji Vasudevan , Mayrose Maya , Sherf Ofra , Jacob-Hirsch Jasmine , Eichenlaub Rudolf , Iraki Naim , Manulis-Sasson Shulamit , Rechavi Gideon , Barash Isaac , Sessa Guido 
Published: February 2008

AbstractClavibacter michiganensis subsp. michiganensis (Cmm) is a gram-positive actinomycete, causing bacterial wilt and canker disease in tomato (Solanum lycopersicum). Host responses to gram-positive bacteria and molecular mechanisms associated with the development of disease symptoms caused by Cmm in tomato are largely unexplored. To investigate plant responses activated during this compatible interaction, we used microarray analysis to monitor changes in host gene expression during disease development. This analysis was performed at 4 d postinoculation, when bacteria were actively multiplying and no wilt symptoms were yet visible; and at 8 d postinoculation, when bacterial growth approached saturation and typical wilt symptoms were observed. Of the 9,254 tomato genes represented on the array, 122 were differentially expressed in Cmm-infected plants, compared with mock-inoculated plants. Functional classification of Cmm-responsive genes revealed that Cmm activated typical basal defense responses in the host, including induction of defense-related genes, production and scavenging of free oxygen radicals, enhanced protein turnover, and hormone synthesis. Cmm infection also induced a subset of host genes involved in ethylene biosynthesis and response. After inoculation with Cmm, Never ripe (Nr) mutant plants, impaired in ethylene perception, and transgenic plants with reduced ethylene synthesis showed significant delay in the appearance of wilt symptoms, compared with wild-type plants. The retarded wilting in Nr plants was a specific effect of ethylene insensitivity, and was not due to altered expression of defense-related genes, reduced bacterial populations, or decreased ethylene synthesis. Taken together, our results indicate that host-derived ethylene plays an important role in regulation of the tomato susceptible response to Cmm.
Satellite attitude control by integrator back‐stepping with internal stabilization
Authors: Özgür Doruk Reşat , Kocaoğlan Erol 
Published: February 2008

PurposeThis paper aims to focus on the implementation of the integral back‐stepping control on the model of BILSAT – 1 satellite of the Turkish Scientific and Technological Research Council (TUBITAK).Design/methodology/approachThe nonlinear model of the satellite is divided into three groups and the control Lyapunov function is constructed systematically. The formed closed loop system is analyzed for stability according to a recently developed stability analysis procedure and multi‐run simulations.FindingsSince the studied model includes the dynamics of a practical reaction wheel (SSTL Type: Microwheel), the simulation results showed that the designed controllers are suitable for practical application. The torque requirement is far below the maximum torque supplied by the wheel. In addition, the system seems to be quite fast and robust against the parametric uncertainties.Research limitations/implicationsSince the control system is nonlinear, the computational complexity will be an issue in practical application. The stability analysis should be improved to have more reliable information concerning the disturbance torques. Currently this analysis is performed by multi‐run simulations. An observer or estimator may also be designed in order to compute the attitudes from the gyroscope readings.Practical implicationsThe controller designed here can be implemented on the proceeding satellite projects (foregoing BILSAT projects) by TUBITAK.Originality/valueThe paper provides a satellite control application of back‐stepping using a model involving modified Rodriguez parameters and reaction wheel dynamics that is not studied in the literature.
Simplest AB‐thermonuclear space propulsion and electric generator
Authors: Bolonkin Alexander 
Published: February 2008

PurposeThis paper aims to suggest a new thermonuclear space propulsion and electric generator for aerospace.Design/methodology/approachMethods of thermonuclear physics are used for research.FindingsThe paper applies, develops and researches mini‐sized Micro‐AB thermonuclear reactors for space propulsion and space power systems. These small engines directly convert the high‐speed charged particles produced in the thermonuclear reactor into vehicle thrust or vehicle electricity with maximum efficiency. The simplest AB‐thermonuclear propulsion offered allows spaceships to reach speeds of 20,000‐50,000 km/s (1/6 of light speed) for fuel ratio 0.1 and produces a huge amount of useful electric energy. The offered propulsion system permits flight to any planet of the solar system in a short time and to the nearest non‐Sun stars by E‐being or intellectual robots during a single human life period.Research limitations/implicationsTechnical limitations may be apparent.Originality/valueThe theory of this propulsion and electric generator is developed and possibilities researched.
Control system design of multivariable non‐linear space robots
Authors: Nassirharand Amir 
Published: February 2008

PurposeThe paper's purpose is to initiate an effort that will result in a systematic approach for design of control systems for multivariable, nonlinear, and unstable space robots.Design/methodology/approachThe design approach is based on multivariable describing function (DF) models of the space robot coupled with the use of factorization technique. The design approach is to obtain the multivariable DF models followed by application of a previously developed factorization‐based controller design formula. Finally, the design must be verified by a non‐linear simulation to make sure that approximations made during design are valid.FindingsIt is found that the DF approach may successfully be applied in order to control nonlinear, multivariable, and unstable systems such as space robots.Research limitations/implicationsAt present, the approach is verified to be applicable to rigid space robots.Practical implicationsThe major outcome of this research is that complicated controllers of a class of space robots may be replaced by simpler controllers, taking into account the amplitude dependency features of the space robot; this amplitude dependency is the most important characteristic of a non‐linear system.Originality/valueThis is the first paper in the area of multivariable and unstable space robot controller design that is based on the application of the DF technique. In fact this is the first work in the area of general unstable non‐linear control system design that is based on a DF technique.
Influence of flexible interface on the performance of whole spacecraft vibration isolation
Authors: Lu Liang , Huang Wenhu 
Published: February 2008

PurposeAs the installation of the vibration isolation device to the spacecraft for the whole spacecraft vibration isolation, the interface structure is typically modeled as a rigid structure during the design phase. However, the flexibility of the interface structure does exist for a large‐sized adaptor. This is a source of uncertainty and could reduce the reliability of the system. It is necessary to investigate the influence of this type of flexibility on the vibration isolation performance in an engineering practice. This paper aims to address this situation.Design/methodology/approachThe vibratory transmissibility from the bottom of the isolator is generally used to evaluate the performance of the vibration isolation. By introducing the interface flexibility from both the adaptor and the vibration isolation device, a planar model which includes a flexible beam representing the interface structure is established to study the influence of this type of flexibility on the vibratory transmissibility.FindingsIt is found that, when this type of flexibility is included, an extra low‐frequency mode dominated locally by the interface structure is induced, and then a significant resonance appears in the vibratory transmissibility of the vibration isolation device at a low frequency.Originality/valueThe vibration isolation performance may be over‐estimated in the design by taking the interface as rigid. The inherent flexibility of the interface structure, on the other hand, may degrade the performance of the vibration isolation device and degrade the function of the rotation constraint device added into the vibration isolation device.
Novel design of actuator fault reconstruction
Authors: Luan Jia‐hui , Zhao Ting‐di 
Published: February 2008

PurposeThis paper aims to present a novel fault estimator design scheme, in order to improve the practicability of the fault estimation.Design/methodology/approachThe paper first transforms the system state into three parts. Then a reduced‐observer is designed for an unknown input and fault‐free system, and the observer can get no bias error in the state estimation. So the estimator can get the exact estimation for the unknown input and fault of the actuator.FindingsBy using this approach it is found that the condition of the estimator is weaker than other observers. It is a qualified and simple and straightforward approach to be applied in wide domains.Research limitations/implicationsIt should be noted that the sensors should be perfectly reliable. The maximum number of disturbances which can be decoupled cannot be larger than the number of independent actuators.Practical implicationsIt is a very useful approach to solve the problem that the actuator is contaminated by disturbances.Originality/valueThe paper uses a transformation to divide the state into three parts. By estimating the part that is not affected by the disturbance and fault, it gets the exact estimation for the unknown input and fault of the actuator. The design condition of the reduced‐order observer which is proposed is weaker than others.
Design and development of thermal test model of a micro‐satellite for thermal balance test
Authors: Justin Jose Nesamani Gilbert , Chandrakant Joshi Sunil , Jin Zhanli , Keong Chan Poh , Cheng Lee Soon 
Published: February 2008

PurposeThis paper seeks to provide an insight into the design and development of the thermal test model (TTM) of X‐Sat, a 120 kg class micro‐satellite, being developed at the Centre. This model was specifically constructed for carrying out a thermal balance test (TBT) in a 4 m diameter vertical thermal vacuum chamber.Design/methodology/approachThe construction of the thermal model followed a structural mock‐up model which was modified thermally to suit the purpose. Specific and careful consideration was given to the geometry and, more importantly, thermal characteristics such as thermal mass, surface properties, etc. to mimic the actual satellite configuration as closely as possible. Test plans were devised to qualify the fabricated components to meet the out‐gassing and other thermal requirements for the model. Design and qualification of supporting frame and linkages for TBT are also covered.FindingsIt is possible to simulate the thermal characteristics of a micro‐satellite in orbit under a different mission scenario through proper scaling and using alternative material options while developing TTM.Originality/valueThe paper discusses in detail the simplified cost‐effective approach of constructing TTM and also outlines the various issues to be considered for a TBT. It provides valuable information needed for micro‐satellite designers.
Coordinative structures and development of food supply chains
Authors: Mikkola Minna 
Published: February 2008

PurposeThis case study aims to analyse dyadic empirical relations within food supply chains. The categories of market, hierarchy or power, network and social relations were used to disclose the coordinative structures on the chain level and connect these with the chain development.Design/methodology/approachThe actors of three vegetable supply chains were interviewed. The coordinative relations of actors were identified and the coordinative structures on the chain level were made visible by combining the ego networks of chain actors. The “story of supply chain development” was intertwined with the analysis.FindingsThe studied food supply chains were coordinated mostly by duplex or multiplex relations, combining market, hierarchy or power, network and social relations. In addition to the strategic network, presented in literature, the study identified a coordinative structural mode of socially overlaid network. In general, the network relation was found to be used as an effective “glue” within all coordinative structures. Both coordinative structural modes exhibited substantial growth, on the condition that agricultural base and buyers enabled enlargement.Originality/valueEconomic sociological perspective has been used in explaining food supply chain development by making visible the coordinative relations and structures on the chain level. The chain level phenomena appear as a promising field of study.
The paradox of gifted leadership: developing the generation of leaders
Authors: Hammett Pete 
Published: February 2008

PurposeThe purpose of this paper is to highlight the paradox of gifted leadership – namely that executives who are gifted in leading their organizations may not be able to develop leaders under them – creating a challenge in developing the next generation of leaders.Design/methodology/approachTo help confront this paradox the paper highlights insights for how executives approach developing others by drawing on assessment data from over 100 executive leaders and 900 observers. Additionally, the paper reflects on current research and observations on talent management best practices and offers a call‐to‐action for establishing a leadership development framework.FindingsSenior leaders do not get too close or too personal with their co‐workers and this isolation can inhibit their ability to identify first hand individuals who might be in the up‐and‐coming next generation of leaders. Likewise, there is a perception that executives are more concerned with advancing their own careers than helping others move up the ladder. Finally, in environments with informal talent management processes, executives can be drawn towards finding and grooming mirror images of themselves or worse may succumb to organizational politics and favoritism when it comes to promotions and advancements.Originality/valueThere are multiple “influencers” that come into play to shape an executive's behavior and perceptions in their struggle to be an effective leader. Hopefully, with a better awareness of these influencers we can bring balance to how we define (and perhaps influence) effective executive leadership.
Driving organizational change with internal coaching programs: part one
Authors: Rock David , Donde Ruth 
Published: February 2008

PurposeThe purpose of this two part paper is to outline a new way of utilizing coaching to drive wide scale organizational change.Design/methodology/approachThe authors illustrate the various benefits to using internal coaches, flesh out the cost benefits, and highlight a range of ways that organizations can integrate coaching into their people, performance and culture frameworks. It covers training, design and implementation issues as well as looking at aligning coaching models with the organization's strategic approach. The paper draws on extensive case studies and posits some best practice principles, then addresses some of the key questions around this topic. This paper draws on interviews with over 50 internal coaches over two years, and several other research papers on this topic.FindingsIt illustrates how training leaders to be internal coaches is a more scalable, sustainable and robust approach to driving change and improving performance than hiring external coaches. Early indicators are showing significant increases in retention, engagement, productivity and performance, as well as ROI (17x), across organizations that have developed internal coaching.Research limitations/implicationsData is critical to understanding coaching impacts within organizational contexts. Thanks to those organizations using measurement, impacts to the business can be determined.Originality/valueThis positive data is significant for organizations making decisions about introducing coaching initiatives, driving organizational change or adopting a coaching culture.
Effecting successful change management initiatives
Authors: Stanleigh Michael 
Published: February 2008

PurposeThe purpose of this paper is to assist managers to effectively implement change initiatives.Design/methodology/approachThe author provides his viewpoint for a step‐by‐step approach to implementing change on the basis of his professional experience.FindingsMost change initiatives fail because management may not be engaging employees in the process towards change and do not allow sufficient time for changes to set. It is important to implement change in a series of phases that will engage employees and to allow sufficient length of time for each phase to become institutionalized within the organization.Practical implicationsThe author invites managers to apply a multi‐step process to guide, include, empower, enlist, and motivate employees towards change.Originality/valueSenior managers will understand why change initiatives usually fail and how to effect successful change management initiatives in their organizations or departments.
Using collaboration tools to improve training
Authors: Noonan Jerona 
Published: February 2008

PurposeThe purpose of the paper is to examine how collaboration services can benefit the training process, to the benefit of both the individual and broader organisation. In the past, conferencing tools were viewed almost exclusively in terms of the financial benefits they delivered to the business, yet increasingly businesses recognise their value in enabling staff, irrespective of their location, to access the company's invaluable knowledge base.Design/methodology/approachThe paper explores how sophisticated online collaboration solutions complement face‐to‐face training and follow‐up coaching and support by replicating much of its physical functionality and two‐way communication capability.FindingsIn achieving this, it shows how collaboration has moved on from its traditional focus on one‐to‐many to providing one‐to‐one unified communication through the use of tools such as chat and feedback mechanisms including e‐quizzes, votes and surveys. Availability is one thing, usage is another however and here, if they are to encourage maximum participation and usage in a training context, such tools must be easy to deploy, easy to use and offer ubiquitous access.Originality/valueThe value of this approach is to show how, from a training perspective, the latest collaboration services offer a uniquely broad and cost‐effective mechanism in getting beyond traditional geographical, cultural and technological barriers to share work‐related skills, techniques and product knowledge.
Corporate re‐branding: is cultural alignment the weakest link?
Authors: Gotsi Manto , Andriopoulos Constantine , Wilson Alan 
Published: February 2008

PurposeThis study seeks to empirically examine cultural alignment with new corporate brand values in the rebranding aftermath.Design/methodology/approachFocuses on a case study of a firm that recently underwent a corporate rebranding campaign. Analysis is based on data collected through 14 in‐depth interviews with senior managers, and questionnaire data from an intranet survey with the firm's employees.FindingsThe empirical findings highlight that despite the firm's internal communication initiatives, current staff attitudes and behaviours are not aligned with the new corporate brand priorities. Resistance to change appears to play an important role in this respect. Yet, interestingly, some divisions view the current culture as more aligned to the new corporate brand than others. Moreover, staff that have joined the firm after the rebranding exercise view the current culture as more aligned to the new corporate brand values than those who have been with the firm since before the launch of the new corporate brand.Research limitations/implicationsA single case study but one which provides empirical insights that advance theoretical thinking in corporate re‐branding.Practical implicationsManagers should aim for organization‐wide buy‐in towards the new corporate brand values and address challenges involved in aligning subcultures with the requirements of the new corporate brand.Originality/valueVery few papers have empirically studied the process of cultural alignment in corporate re‐branding. This paper is relevant to managers of organizations undertaking corporate re‐branding activities.