bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computational kinematics for robotic manipulators: Jacobian problems
Authors: Altuzarra O. , Salgado O. , Petuya V. , Hernández A. 
Published: January 2008

PurposeThis paper aims to provide tools for the complete Jacobian analysis of robotic manipulators of general topology, using a comprehensive velocity equation.Design/methodology/approachFirst, a modelling process is made in order to build the velocity equation using simple constraint equations: i.e. length restriction, relative motion and rigid body constraints. Then the motion space is solved, i.e. the space that spans all feasible motions of the manipulator.FindingsThe velocity equation is comprehensive, i.e. it relates all kinematic variables, not only input and output. The Jacobian related to the comprehensive velocity equation is a square dimensionless matrix. This characteristic has great importance when evaluating manipulability or closeness to singularities. Employing the motion space, any kinematic entity can be studied: i.e. velocities and accelerations of any active/passive joints, screw axis, axodes, and so on. Also a comprehensive singularity analysis can be made.Research limitations/implicationsThe approach presented is focused on the kinetostatic analysis of manipulators and, therefore, subjected to rigid body assumption.Practical implicationsThe paper presents a proposal of effective codes for engineering analysis of manipulators.Originality/valueThis approach is based on a pure computational kinematic analysis that unifies all kinetostatic analysis for any manipulator topology (i.e. serial, parallel, hybrid manipulators, complex mechanisms, redundant‐or non‐redundant‐actuated). The characteristic Jacobian matrix is dimensionless and provides the means for a complete singularity analysis and an effective use of indicators.
Supply chain integration improves performance: the Emperor's new suit?
Authors: Fabbe‐Costes Nathalie , Jahre Marianne 
Published: January 2008

PurposeIn the literature authors state that there is a positive relation between supply chain integration (SCI) and performance. They claim that this relation is widely discussed and supported empirically. Other authors, however, suggest that integration might be more difficult in practice than in theory, that it should be differentiated and that it is more rhetoric than reality. As integration has been core of logistics and supply chain management since the 1980s, the purpose of this paper is to investigate these somewhat contradictory statements and analyse prior studies regarding definitions and measures of integration and performance as well as the reported empirical evidence on their relation.Design/methodology/approachBased on an extensive and systematic review of integration articles within four highly ranked academic journals in logistics, supply chain and operations management, this paper presents and discusses the results of prior empirical studies on relations between integration and performance.FindingsThe analysis of the relevant articles indicates that empirical evidence cannot permit to clearly conclude and that integration as well as performance is defined, operationalised and measured in different and often limited ways. This might be a problem and the paper concludes with a provoking question of whether SCI might be the Emperors' New Suit of business.Originality/valueThe paper's departure point is a controversial hypothesis: the contribution of SCI is not as obvious as logistics and supply chain researchers usually think. The rigorous selection and analysis of previous studies contributes with systematic knowledge within an important question.
Summer nights
Authors: Macdowall Wendy , Wellings Kaye , Stephenson Judith , Glasier Anna 
Published: January 2008

PurposeThis paper aims to examine whether greater consideration should be given to the timing of sexual health interventions within the calendar year.Design/methodology/approachThe paper uses a review of the literature.FindingsThe evidence points to seasonality in a number of areas of sexual health among young people, including: the timing of first intercourse and conceptions, both of which peak in the summer and over Christmas; abortions which peak approximately two months later in February and late summer and sexually transmitted infections, which peak over the summer and autumn. In the case of conceptions there is evidence that the seasonal pattern among young people is different from that of adults. Potential explanations fall into four main categories: biological; behavioural; social, and service‐related.Research limitations/implicationsMany of the studies included in this review are from the USA, and some are based on either small samples or specific risk groups, which raises questions of representativeness and generalisability. Further, it is notable how little research there has been regarding seasonal variations in other aspects of sexual behaviour, such as risk reduction practice and other potential explanatory factors such as health‐seeking behaviour and availability of services.Practical implicationsThe findings consistently point to periods of heightened sexual activity among young people in the summer and over Christmas, and suggest that greater consideration should indeed be given to the timing of sexual health interventions within the calendar year.Originality/valueTo the best of the authors' knowledge, no other review of this kind has yet been found.
Hitting back: strategic responses to low‐cost rivals
Authors: Morehouse Jim , O'Meara Bob , Hagen Christian , Huseby Todd 
Published: January 2008

Purpose of this paperNo company is safe from low‐cost rivals. Almost overnight, nimble low‐cost competitors can exploit their offshore advantage, partnerships, and inexpensive technologies to break down barriers and rewrite the rules of competition. This paper aims to show how to counterattack.Design/methodology/approachThe paper shows that way to beat low‐cost competitors that have the potential to become serious competitors is to identify and deal with them early, before they get a foothold in a market.FindingsThe paper finds that the best way to identify and thwart a low‐cost rival is to adopt its mindset, anticipate its next competitive move and measure your costs against its costs. This best practice analysis requires four steps.Practical implications“What to do” to defeat low‐cost competitors involves two separate but related tasks: First, “stop the bleeding”, and second, reposition the company for success in the new market. The paper shows how to break down potential moves into short‐term tactics and long‐term strategies.Originality/valueThe paper shows how to win the battle with a low‐cost competitor by identifying the genuine threats, taking on the serious competition, adapting its tactics quickly and hitting back with a well‐placed blow.
Interview with growth consultant Chris Zook: a less risky path to business model innovation
Authors: Davidson Alistair , Leavy Brian 
Published: January 2008

PurposeCreating a fundamentally different business in the shadow of the old one – while its assembly lines continue to roll – is a daunting challenge. Bain consultant Chris Zook recently published the last book in a trilogy which addresses the question of how to make “fundamental change in your business model, while still running your business.”. This paper aims to explores his views on this subject.Design/methodology/approachFor this interview, two Strategy & Leadership senior editor's – one a Silicon Valley consultant and former CEO and the other an academic – – asked Zook to take them on a guided tour of his reinvention process.FindingsThe paper finds that the underlying thesis in each of the three books is that companies need to master all phases of a strategic life cycle: from extracting the full potential from their core business, to expanding their business successfully, to redefining themselves For most companies and in more industries, the strategy cycle – from Focus, to Expand, to Redefine – has become shorter, and therefore companies frequently confront moments of redefinition of their core.Practical implicationsIn this interview, Zook's how‐to advice for managers covers: the role of hidden assets, the “state of the core diagnostic” tool, the “shrink to grow” strategy, how to test “the waters,” and the FER (focus‐expand‐redefine) cycle.Originality/valueBecause the interview considers the whole trilogy the reader gets a unique view of how Zook's ideas fit together and build a cogent thesis.
Offences concerning directors and officers of a company
Authors: Scanlan G. 
Published: January 2008

PurposeThe purpose of this paper is to consider the present and possible future nature of the legal regime regulating and seeking to control fraud and corruption on the part of directors and officers of companies in the UK.Design/methodology/approachThis paper outlines aspects in the present and future fight against fraud and corruption on the part of directors and officers of companies, particularly with regard to public and listed companies in the UK.FindingsThe paper emphasises the need for the UK Government to secure adequate resources for the investigating and enforcement authorities to ensure that the law of fraud and corruption is effectively enforced, rather than pursue a policy of constant enactment of new legislation which is increasingly complex and ineffective.Originality/valueThe paper considers the creation of a new generic offence to supplement the new generic offences created under the Fraud Act 2006, based on the established principle of the fiduciary duty, a duty owed by all directors and officers to their companies. These offences could form the central core of a future legal regime regulating the conduct of directors and officers.
How long should a training program be? A field study of “rules‐of‐thumb”
Authors: Cole Nina 
Published: January 2008

PurposeThis study aims to examine the question of how long a behavioral skills training program should be in order to result in measurable behavioral change.Design/methodology/approachAn empirical field study was conducted to compare two different lengths of time for a managerial skills training program aimed at achieving behavioral change. The training time for the first training condition was based on “rules‐of‐thumb” found in the literature. The training time was increased in an “extended” training condition that covered the same material but permitted more time for lecture, role‐playing and discussion.FindingsResults showed that, relative to a control group, participants in the “extended” training condition exhibited behavioral change, but those in the “rules‐of‐thumb” training condition did not. Self‐efficacy increased significantly for trainees in both training conditions.Practical implicationsMore attention is required to the length of training programs as they are being designed, especially if behavioral change is a goal of the training. Using rules‐of‐thumb regarding training length may be insufficient for bringing about behavioral change. More importantly, the need for more effective management skills will not be met, and organizational performance outcomes may be jeopardized.Originality/valueThe results of this research have the potential to be broadly applicable to management training and may possibly generalize to training in other disciplines where the training is intended to effect behavioral change.
Alternative measures to value at risk
Authors: Thompson Colin J. , McCarthy Michael A. 
Published: January 2008

PurposeThe purpose of this article is to introduce a new method of estimating risk as an alternative to value at risk (VaR), drawing on the risk assessment literature in environmental science.Design/methodology/approachA commonly used and accepted measure of market risk is VaR, defined as the difference between initial portfolio value and a probabilistic lower bound B on the portfolio value at time T. To take account of situations where the portfolio value may fall below B prior to time T, an an alternative to VaR is proposed based on first passage time distributions.FindingsIt is argued that the resulting expected minimum portfolio value over the time frame T provides a clear alternative measure of market risk. Analytical expressions are obtained and numerical comparisons given when the distribution of portfolio returns is lognormal.Research limitations/implicationsAnalytical results are presented for lognormal distributions for returns. Results for other models can be easily obtained from simulation.Practical implicationsThe new measure of risk recognizes that investors might be sensitive to risks of decline in the value of a portfolio at any time within a given time horizon, not just at the end of the anticipated period of investment. The expected minimum portfolio value measures the largest loss that is expected at some stage over that period.Originality/valueA new measure of risk is presented that arises from literature on risk assessment in environmental science. It is complementary to VaR for assessing risk.
Energy‐efficient adaptive resource management strategy for large‐scale mobile ad hoc networks
Authors: Shi Shengfei , Li Jianzhong , Wang Chaokun , Wu Yuhui 
Published: January 2008

PurposeThe purpose of this paper is to propose a novel resource management strategy, which needs no special frameworks and directory servers.Design/methodology/approachThe key idea is to piggyback a little extra packet header on the normal routing message by resource providers randomly. The clients can obtain the resource information gradually and need no dedicated resource queries.FindingsThe results of simulation confirm the good performance of our algorithms in different situations in terms of query latency and power consumption.Originality/valueA novel resource management strategy, which needs no special frameworks and directory servers. The approach can be used in many current routing protocols. The quality of service issue is also considered for resource discovery algorithm and broadcasting method.
Lipase Expression in
Pseudomonas alcaligenes
Is Under the Control of a Two-Component Regulatory System
Authors: Krzeslak Joanna , Gerritse Gijs , van Merkerk Ronald , Cool Robbert H. , Quax Wim J. 
Published: January 2008

ABSTRACT

Preliminary observations in a large-scale fermentation process suggested that the lipase expression of
Pseudomonas alcaligenes
can be switched on by the addition of certain medium components, such as soybean oil. In an attempt to elucidate the mechanism of induction of lipase expression, we have set up a search method for genes controlling lipase expression by use of a cosmid library containing fragments of
P. alcaligenes
genomic DNA. A screen for lipase hyperproduction resulted in the selection of multiple transformants, of which the best-producing strains comprised cosmids that shared an overlapping genomic fragment. Within this fragment, two previously unidentified genes were found and named
lipQ
and
lipR
. Their encoded proteins belong to the NtrBC family of regulators that regulate gene expression via binding to a specific upstream activator sequence (UAS). Such an NtrC-like UAS was identified in a previous study in the
P. alcaligenes
lipase promoter, strongly suggesting that LipR acts as a positive regulator of lipase expression. The regulating role could be confirmed by down-regulated lipase expression in a strain with an inactivated
lipR
gene and a threefold increase in lipase yield in a large-scale fermentation when expressing the
lipQR
operon from the multicopy plasmid pLAFR3. Finally, cell extracts of a LipR-overexpressing strain caused a retardation of the lipase promoter fragment in a band shift assay. Our results indicate that lipase expression in
Pseudomonas alcaligenes
is under the control of the LipQR two-component system.
Changes in Bacterial and Archaeal Community Structure and Functional Diversity along a Geochemically Variable Soil Profile
Authors: Hansel Colleen M. , Fendorf Scott , Jardine Phillip M. , Francis Christopher A. 
Published: January 2008

ABSTRACT

Spatial heterogeneity in physical, chemical, and biological properties of soils allows for the proliferation of diverse microbial communities. Factors influencing the structuring of microbial communities, including availability of nutrients and water, pH, and soil texture, can vary considerably with soil depth and within soil aggregates. Here we investigated changes in the microbial and functional communities within soil aggregates obtained along a soil profile spanning the surface, vadose zone, and saturated soil environments. The composition and diversity of microbial communities and specific functional groups involved in key pathways in the geochemical cycling of nitrogen, Fe, and sulfur were characterized using a coupled approach involving cultivation-independent analysis of both 16S rRNA (bacterial and archaeal) and functional genes (
amoA
and
dsrAB
) as well as cultivation-based analysis of Fe(III)-reducing organisms. Here we found that the microbial communities and putative ammonia-oxidizing and Fe(III)-reducing communities varied greatly along the soil profile, likely reflecting differences in carbon availability, water content, and pH. In particular, the
Crenarchaeota
16S rRNA sequences are largely unique to each horizon, sharing a distribution and diversity similar to those of the putative (
amoA
-based) ammonia-oxidizing archaeal community. Anaerobic microenvironments within soil aggregates also appear to allow for both anaerobic- and aerobic-based metabolisms, further highlighting the complexity and spatial heterogeneity impacting microbial community structure and metabolic potential within soils.
Protein Engineering of Toluene Monooxygenases for Synthesis of Chiral Sulfoxides
Authors: Feingersch Roi , Shainsky Janna , Wood Thomas K. , Fishman Ayelet 
Published: January 2008

ABSTRACT

Enantiopure sulfoxides are valuable asymmetric starting materials and are important chiral auxiliaries in organic synthesis. Toluene monooxygenases (TMOs) have been shown previously to catalyze regioselective hydroxylation of substituted benzenes and phenols. Here we show that TMOs are also capable of performing enantioselective oxidation reactions of aromatic sulfides. Mutagenesis of position V106 in the α-hydroxylase subunit of toluene
ortho
-monooxygenase (TOM) of
Burkholderia cepacia
G4 and the analogous position I100 in toluene 4-monooxygenase (T4MO) of
Pseudomonas mendocina
KR1 improved both rate and enantioselectivity. Variant TomA3 V106M of TOM oxidized methyl phenyl sulfide to the corresponding sulfoxide at a rate of 3.0 nmol/min/mg protein compared with 1.6 for the wild-type enzyme, and the enantiomeric excess (pro-
S
) increased from 51% for the wild type to 88% for this mutant. Similarly, T4MO variant TmoA I100G increased the wild-type oxidation rate by 1.7-fold, and the enantiomeric excess rose from 86% to 98% (pro-
S
). Both wild-type enzymes showed lower activity with methyl
para
-tolyl sulfide as a substrate, but the improvement in the activity and enantioselectivity of the mutants was more dramatic. For example, T4MO variant TmoA I100G oxidized methyl
para
-tolyl sulfide 11 times faster than the wild type did and changed the selectivity from 41% pro-
R
to 77% pro-
S
. A correlation between regioselectivity and enantioselectivity was shown for TMOs studied in this work. Using in silico homology modeling, it is shown that residue I100 in T4MO aids in steering the substrate into the active site at the end of the long entrance channel. It is further hypothesized that the main function of V106 in TOM is the proper positioning or docking of the substrate with respect to the diiron atoms. The results from this work suggest that when the substrate is not aligned correctly in the active site, the oxidation rate is decreased and enantioselectivity is impaired, resulting in products with both chiral configurations.
Bombyx mori
Midgut Membrane Protein P252, Which Binds to
Bacillus thuringiensis
Cry1A, Is a Chlorophyllide-Binding Protein, and the Resulting Complex Has Antimicrobial Activity
Authors: Pandian Ganesh N. , Ishikawa Toshiki , Togashi Makoto , Shitomi Yasuyuki , Haginoya Kohsuke , Yamamoto Shuhei , Nishiumi Tadayuki , Hori Hidetaka 
Published: January 2008

ABSTRACT

The epithelial cell membrane 252-kDa protein (P252) isolated in our laboratory from
Bombyx mori
midgut was shown to bind strongly with Cry1Aa, Cry1Ab, and Cry1Ac toxins of
Bacillus thuringiensis
(15). In the current paper, P252 was shown to bind with chlorophyllide (Chlide) to form red fluorescent protein (RFP) complex, termed Bm252RFP, with absorbance and fluorescence emission peaks at 600 nm and 620 nm, respectively. P252 at a concentration of 1 μM is shown to bind with about 50 μM Chlide in a positively cooperative reaction to form Bm252RFP under aerobic conditions and in the presence of light at 37°C. Various parameters influencing this reaction have been optimized for efficient in vitro chemical synthesis of Bm252RFP. Circular dichroism spectra revealed that P252 is composed of a β-structure (39.8% ± 2.2%, based on 5 samples) with negligible contribution of α-helix structure. When bound to Chlide, the β-structure content in the complex is reduced to 21.6% ± 3.1% (
n
= 5). Since Chlide had no secondary structure, the observed reduction suggests significant conformational changes of P252 during the formation of Bm252RFP complex. Bm252RFP had antimicrobial activity against
Escherichia coli
,
Serratia marcescens
,
B. thuringiensis
, and
Saccharomyces cerevisiae
with 50% effective concentrations of 2.82, 2.94, 5.88 μM, and 21.6 μM, respectively. This is the first report ever to show clear, concrete binding characteristics of the midgut protein to form an RFP having significant antimicrobial activity.
A
Rhodococcus qsdA
-Encoded Enzyme Defines a Novel Class of Large-Spectrum Quorum-Quenching Lactonases
Authors: Uroz Stéphane , Oger Phil M. , Chapelle Emilie , Adeline Marie-Thérèse , Faure Denis , Dessaux Yves 
Published: January 2008

ABSTRACT

A gene involved in
N
-acyl homoserine lactone (N-AHSL) degradation was identified by screening a genomic library of
Rhodococcus erythropolis
strain W2. This gene, named
qsdA
(for
q
uorum-sensing
s
ignal
d
egradation), encodes an N-AHSL lactonase unrelated to the two previously characterized N-AHSL-degrading enzymes, i.e., the lactonase AiiA and the amidohydrolase AiiD. QsdA is related to phosphotriesterases and constitutes the reference of a novel class of N-AHSL degradation enzymes. It confers the ability to inactivate N-AHSLs with an acyl chain ranging from C
6
to C
14
, with or without substitution at carbon 3. Screening of a collection of 15
Rhodococcus
strains and strains closely related to this genus clearly highlighted the relationship between the ability to degrade N-AHSLs and the presence of the
qsdA
gene in
Rhodococcus
. Bacteria harboring the
qsdA
gene interfere very efficiently with quorum-sensing-regulated functions, demonstrating that
qsdA
is a valuable tool for developing quorum-quenching procedures.
Molecular Detection of
Enterocytozoon bieneusi
and Identification of a Potentially Human-Pathogenic Genotype in Milk
Authors: Lee John Hwa 
Published: January 2008

ABSTRACT

Milk specimens from 180 dairy cows were examined for the presence of
Enterocytozoon bieneusi
, using molecular assays. Fifteen specimens were found to be positive, of which 3 were identical to the human
E. bieneusi
types, which suggests that some
E. bieneusi
isolates from milk can infect humans. Overall, dairy cows' milk may play a significant role in the transmission of
E. bieneusi
infections to humans.