bluuebunny/crossref_metadata_2025_split huggingface dataset:
Designing an integrative model of leagile production and analyzing its influence on the quality of auto parts based on Six Sigma approach with a case study in a manufacturing company
Authors: Shahin Arash , Jaberi Rezvan 
Published: August 2011

PurposeThe purpose of this paper is to propose an integrative model of leagile production and to examine its influence on the quality of products based on Six Sigma approach.Design/methodology/approachA new model has been proposed in which the three strategies of postponement, mass customization, and modularization are included together with an executive algorithm. The proposed model has been examined using three main products of the Ghods Manufacturing Group, which is a manufacturer of truck body parts, from March to July 2008. In the case study, upstream and downstream processes (after processes warehousing of the semi‐manufactured parts) have been considered for the implementation of lean and agile production strategies, respectively. The product waiting time in the production section has been considered as the lean production indicator, and the warehousing time in the final warehouse has been considered as the indicator of agile manufacturing. These indicators have been evaluated before and after implementation of the proposed model and the sigma level of the studied processes has been evaluated.FindingsThe results imply that the sigma level the product A has been improved by 147 percent considering the first indicator and by 8 percent considering the second indicator. Also, product B has 65 and 47 percent and product C has 65 and 150 percent of improvement considering the two indicators, respectively.Research limitations/implicationsThe proposed model has not been implemented in a wide range of operations and has not covered all of the products of the case study. Also, due to the lack of literature on standard criteria for evaluating leagile production, the criterion of the duration of waste has been defined and used for leanness and the duration of final storage has been defined and applied to assembly line based on specific orders from customers, which in turn might be realized as a limitation. In comparing the process before and after improvement, there might exist other unknown factors by which, results would be affected.Originality/valueWhile the literature includes researches on leagile production and its advantages, this investigation further proposes a leagile production model which includes three strategies of postponement, mass customization, and modularization and is employed based on Six Sigma approach.
The role of the physical layout in the implementation of lean management initiatives
Authors: Soriano‐Meier Horacio , Forrester Paul L. , Markose Sibi , Arturo Garza‐Reyes Jose 
Published: August 2011

PurposeThe purpose of this paper is to investigate the impact of layout configurations in a hospital on the implementation of lean management initiatives, to include different units of care. The research concentrated on the impact, the physical distance between dependent units could have on staff perception, use of staff time, time spent in the system by patients, and performance.Design/methodology/approachThe research examined the relationship between clinical units allocated within Northampton General Hospital and their internal providers. In addition, an adapted version of the SERVPERF questionnaire was used to measure the quality perception of staff.FindingsThe transit distances from each clinical unit to their internal providers have: a negative relationship with the staff quality provision of care; a positive relationship with the time the patient spends in the system; and no discernable direct correlation with performance.Practical implicationsThese findings will help hospital managers to understand the impact of the layout of a hospital on the implementation of service improvement activities, and will assist them in planning improved relocation of clinical units. This facilitates future service improvements whilst optimising the use of available and constrained resources within the present hospital facilities.Originality/valueThe ideas and results presented in this study are original and valuable to the study of hospital layouts, services improvements and the implementation of lean operation initiatives and quality improvement programmes in hospitals. The study also successfully tested the application of SERVPERF in a hospital setting.
Applying the DOE toolkit on a Lean‐and‐Green Six Sigma Maritime‐Operation Improvement Project
Authors: Besseris George J. 
Published: August 2011

PurposeThe purpose of this paper is to provide a case study on endorsing process improvement in maritime operations by implementing design of experiments on Lean Six Sigma performance responses. It is demonstrated how process efficiency and environmental muda may be dealt with simultaneously in a lean‐and‐green project driven by hardcore Six Sigma tools.Design/methodology/approachA 16‐run Taguchi‐type orthogonal design was employed to gather data for vessel speed (VS), exhaust gas temperature (EGT) and fuel consumption (FC) as modulated by a total of 15 controlling parameters synchronously. Active dependencies were inferred based on the desirability analysis method on direct process data from a performance log. This log was maintained for a long‐term monitoring during sea voyages of a double skin bulk carrier of 55,000 DWT while in sea service.FindingsA high composite desirability value was achieved eclipsing the 0.90 mark. Values well over the 0.9 level were also obtained for the three examined individual desirability values of VS, EGT and FC. Leading controlling parameters were discovered to be compressor pressure, fuel pump index, slip, governor index and MIP.Practical implicationsA Lean Six Sigma project is carried out to improve performance characteristics in ordinary maritime operations. While the company in the case study outlined in this article no longer relies on periodic inspections to determine machinery conditions, improvement on key process characteristics were nevertheless deemed worthy of ameliorating. Information retrieval from computerized continuous monitoring systems assisted in conducting experimental designs in order to obtain optimal performance. Specifically, the tuning of vessel main engine running mode was examined aiming at increasing the quality levels of output power to the shaft along with a reduction of NOx emissions.Originality/valueThis work adds an interesting paradigm in the critical field of maritime activities for processes in full gear while operating at sea. Maritime operations are an imperative necessity when expediting international trading transactions. It is the first time that such a case study has emanated from a real pilot Lean Six Sigma project which interlaces process efficiency enhancement with concurrent environmental muda reduction.
Doing business in India: a review of research in leading international journals
Authors: Rienda Laura , Claver Enrique , Quer Diego 
Published: August 2011

PurposeIndia has emerged as one of the major players on the new international business scene. Its unstoppable economic growth since reforms in 1991 has become the focus of attention of researchers in the area of international business and management. The purpose of this paper is to review the research on India that has been published in top business and management journals, with the aim of knowing what are the most influential papers, what are the issues that have received the most attention, which are the main findings or what more needs to be done in terms of research.Design/methodology/approachThe choice of journals was based on previous literature reviews. The authors reviewed 94 papers on India published in the 11 journals selected for the 1991‐2010 period.FindingsThe main results of the review are as follows; although there was great variety between the methodologies used, quantitative papers, including papers that used primary data, were the most frequent. With regard to journals, Journal of World Business, Journal of International Business Studies, International Business Review and Asia Pacific Journal of Management were the journals that had published the most papers on India during this period. The most popular topics were cultural influence and comparison between countries, business practices, studies which focus on one sector or company in India and the business operations and management of foreign companies in India.Originality/valueThe most important contribution of this paper is the overview it provides of the main papers published on business and management in India for the 1991‐2010 period: a period which witnessed significant changes in the country's economy. The paper identifies the journals which have devoted the most interest to this geographical region, which authors have contributed the most and which have been the most popular topics and findings.
Mismatched reproduction is energetically costly for chick feeding female great tits
Authors: te Marvelde Luc , Webber Simone L. , Meijer Harro A. J. , Visser Marcel E. 
Published: August 2011

Summary1. Climate change has caused a phenological mismatch between the timing of reproduction and the local food peak in many bird species. Late breeding birds therefore experience reduced food availability during chick rearing and are thus predicted to have an increased energy expenditure. Observational studies, however, show mixed results, perhaps because they compare energy expenditure across rather than within individuals at different levels of food availability.2. In a cross foster experiment, we measured daily energy expenditure (DEE) twice within individuals during chick feeding (when chicks were 6 and 14 days old) for 28 free‐living female great tits (Parus major). To avoid confounding effects of chick age, these females reared on both occasions a standardized foster brood of eight 10‐day‐old chicks during the 24‐h measuring period. For all birds, food availability declined between the two measurements.3. We show that DEE during chick feeding increased within females when food availability decreased. Variation in DEE within females is partly explained by brood visit rates, food availability and temperature.4. DEE during chick feeding could be affected by the investment in previous stages of the reproductive attempt. However, energy expenditure during chick feeding was not correlated to energy expenditure during egg laying, measured in these same females.5. Understanding of energetic costs during all phases of the reproductive cycle is important to forecast the consequences of climate warming on timing of reproduction.
The discovery–dominance trade‐off is the exception, rather than the rule
Authors: Parr Catherine L. , Gibb Heloise 
Published: August 2011

Summary1. Interspecific trade‐offs are thought to facilitate coexistence between species at small spatial scales. The discovery–dominance trade‐off, analogous to a competition–colonisation trade‐off, is considered an important structuring mechanism in ant ecology. A trade‐off between species’ ability to discover food resources and to dominate them may explain how so many species apparently dependent on similar resources can coexist.2. The discovery–dominance trade‐off is thought to be broken by invasive species in enemy‐free space or territorial species whose activity is fuelled by domination of carbohydrate resources. It may also be mediated by factors such as temperature and habitat structure.3. We investigate the generality and form of the discovery–dominance relationship in an experiment using habitats of contrasting complexity across three continents. In addition, to assess how widespread the discovery–dominance trade‐off is, we conducted a systematic review combining all empirical studies (published and from our experiment).4. From our own fieldwork and meta‐analyses of available studies, we find surprisingly little empirical support for the trade‐off, with results indicating that mean effect sizes were either not significantly different from 0 or significantly positive. The trade‐off was only detected in studies with parasitoids present. Additionally, experimental data from simple and complex habitats within each continent suggest that simple habitats may facilitate both food resource discovery and dominance.5. We conclude that the discovery–dominance trade‐off is the exception, rather than the rule. Instead, these abilities were commonly correlated. Real food resources provide many axes along which partitioning may occur, and discovery–dominance trade‐offs are not a prerequisite for coexistence.
An arctic community of symbiotic fungi assembled by long‐distance dispersers: phylogenetic diversity of ectomycorrhizal basidiomycetes in Svalbard based on soil and sporocarp DNA
Authors: Geml József , Timling Ina , Robinson Clare H. , Lennon Niall , Nusbaum H. Chad , Brochmann Christian , Noordeloos Machiel E. , Taylor D. Lee 
Published: August 2011

AbstractAim  Current evidence from temperate studies suggests that ectomycorrhizal (ECM) fungi require overland routes for migration because of their obligate symbiotic associations with woody plants. Despite their key roles in arctic ecosystems, the phylogenetic diversity and phylogeography of arctic ECM fungi remains little known. Here we assess the phylogenetic diversity of ECM communities in an isolated, formerly glaciated, high arctic archipelago, and provide explanations for their phylogeographic origins.Location  Svalbard.Methods  We generated and analysed internal transcribed spacer (ITS) nuclear ribosomal DNA sequences from both curated sporocarp collections (from Svalbard) and soil polymerase chain reaction (PCR) clone libraries (from Svalbard and the North American Arctic), compared these with publicly available sequences in GenBank, and estimated the phylogenetic diversity of ECM fungi in Svalbard. In addition, we conducted coalescent analyses to estimate migration rates in selected species.Results  Despite Svalbard’s geographic isolation and arctic climate, its ECM fungi are surprisingly diverse, with at least 72 non‐singleton operational taxonomic units (soil) and 109 phylogroups (soil + sporocarp). The most species‐rich genera are Thelephora/Tomentella, Cortinarius and Inocybe, followed by Hebeloma, Russula, Lactarius, Entoloma, Sebacina, Clavulina, Laccaria, Leccinum and Alnicola. Despite the scarcity of available reference data from other arctic regions, the majority of the phylogroups (73.4%) were also found outside Svalbard. At the same time, all putative Svalbard ‘endemics’ were newly sequenced taxa from diverse genera with massive undocumented diversity. Overall, our results support long‐distance dispersal more strongly than vicariance and glacial survival. However, because of the high variation in nucleotide substitution rates among fungi, allopatric persistence since the Pliocene, although unlikely, cannot be statistically rejected. Results from the coalescent analyses suggest recent gene flow among different arctic areas.Main conclusions  Our results indicate numerous recent colonization events and suggest that long‐distance, transoceanic dispersal is widespread in arctic ECM fungi, which differs markedly from the currently prevailing view on the dispersal capabilities of ECM fungi. Our molecular evidence indicates that long‐distance dispersal has probably played a major role in the phylogeographic history of some ECM fungi in the Northern Hemisphere. Our results may have implications for studies on the biodiversity, ecology and conservation of arctic fungi in general.
Spatial patterns in brown bear Ursus arctos diet: the role of geographical and environmental factors
Authors: BOJARSKA Katarzyna , SELVA Nuria 
Published: August 2011

ABSTRACT
We reviewed worldwide spatial patterns in the food habits of the brown bear Ursus arctos in relation to geographical (latitude, longitude, altitude) and environmental (temperature, snow cover depth and duration, precipitation, primary productivity) variables.
We collected data from 28 studies on brown bear diet based on faecal analysis, covering the entire geographical range of this widely distributed large carnivore. We analysed separately four data sets based on different methods of diet assessment.
Temperature and snow conditions were the most important factors determining the composition of brown bear diet. Populations in locations with deeper snow cover, lower temperatures and lower productivity consumed significantly more vertebrates, fewer invertebrates and less mast. Trophic diversity was positively correlated with temperature, precipitation and productivity but negatively correlated with the duration of snow cover and snow depth. Brown bear populations from temperate forest biomes had the most diverse diet. In general, environmental factors were more explicative of diet than geographical variables.
Dietary spatial patterns were best revealed by the relative biomass and energy content methods of diet analysis, whereas the frequency of occurrence and relative biomass methods were most appropriate for investigating variation in trophic diversity.
Spatial variation in brown bear diet is the result of environmental conditions, especially climatic factors, which affect the nutritional and energetic requirements of brown bears as well as the local availability of food. The trade‐off between food availability on the one hand, and nutritional and energetic requirements on the other hand, determines brown bear foraging decisions. In hibernating species such as the brown bear, winter severity seems to play a role in determining foraging strategies. Large‐scale reviews of food habits should be based on several measures of diet composition, with special attention to those methods reflecting the energetic value of food.
Cleavage oxygenases for the biosynthesis of trisporoids and other apocarotenoids in Phycomyces
Authors: Medina Humberto R. , Cerdá‐Olmedo Enrique , Al‐Babili Salim 
Published: August 2011

SummaryMixed cultures of strains of opposite sex of the Mucorales produce trisporic acids and other compounds arising from cleavage of β‐carotene, some of which act as signals in the mating process. The genome of Phycomyces blakesleeanus contains five sequences akin to those of verified carotenoid cleavage oxygenases. All five are transcribed, three of them have the sequence traits that are considered essential for activity, and we have discovered the reactions catalysed by the products of two of them, genes carS and acaA. The transcripts of carS became more abundant in the course of mating, and its expression in β‐carotene‐producing Escherichia coli cells led to the formation of β‐apo‐12′‐carotenal, a C25 cleavage product of β‐carotene. Joint expression of both genes in the same in vivo system resulted in the production of β‐apo‐13‐carotenone, a C18 fragment. In vitro, AcaA cleaved β‐apo‐12′‐carotenal into β‐apo‐13‐carotenone and was active on other apocarotenoid substrates. According to these and other results, the first reactions in the apocarotenoid pathway of Phycomyces are the cleavage of β‐carotene at its C11′–C12′ double bond by CarS and the cleavage of the resulting C25‐fragment at its C13–14 double bond by AcaA.
Two internal type II NADH dehydrogenases of Toxoplasma gondii are both required for optimal tachyzoite growth
Authors: Lin San San , Gross Uwe , Bohne Wolfgang 
Published: August 2011

SummaryIn many apicomplexan parasites the entry of electrons from NADH into the electron transport chain is governed by type II NADH dehydrogenases (NDH2s) instead of a canonical complex I. Toxoplasma gondii expresses two NDH2 isoforms, TgNDH2‐I and TgNDH2‐II with no indication for stage‐specific regulation. We dissected the orientation of both isoforms by using a split GFP assay and a protease protection assay after selective membrane permeabilization. The two approaches revealed that both TgNDH2 isoforms are internal enzymes facing with their active sites to the mitochondrial matrix. Single knockout mutants displayed a decreased replication rate and a reduced mitochondrial membrane potential, which were both more severe in the Tgndh2‐II‐deleted than in the Tgndh2‐I‐deleted mutant. Complementation with a myc‐tagged, ectopic copy of the deleted gene restored the growth rate and the mitochondrial membrane potential. However, an overexpression of the remaining intact isoform could not restore the phenotype, suggesting that the two TgNDH2 isoforms are non‐redundant and possess functional differences. Together, our studies indicate that although TgNDH2‐I and TgNDH2‐II are individually non‐essential, the expression of both internal isoforms is required to maintain the mitochondrial physiology in T. gondii tachyzoites.
Substitutions in the redox‐sensing PAS domain of the NifL regulatory protein define an inter‐subunit pathway for redox signal transmission
Authors: Little Richard , Salinas Paloma , Slavny Peter , Clarke Thomas A. , Dixon Ray 
Published: August 2011

SummaryThe Per‐ARNT‐Sim (PAS) domain is a conserved α/β fold present within a plethora of signalling proteins from all kingdoms of life. PAS domains are often dimeric and act as versatile sensory and interaction modules to propagate environmental signals to effector domains. The NifL regulatory protein from Azotobacter vinelandii senses the oxygen status of the cell via an FAD cofactor accommodated within the first of two amino‐terminal tandem PAS domains, termed PAS1 and PAS2. The redox signal perceived at PAS1 is relayed to PAS2 resulting in conformational reorganization of NifL and consequent inhibition of NifA activity. We have identified mutations in the cofactor‐binding cavity of PAS1 that prevent ‘release’ of the inhibitory signal upon oxidation of FAD. Substitutions of conserved β‐sheet residues on the distal surface of the FAD‐binding cavity trap PAS1 in the inhibitory signalling state, irrespective of the redox state of the FAD group. In contrast, substitutions within the flanking A'α‐helix that comprises part of the dimerization interface of PAS1 prevent transmission of the inhibitory signal. Taken together, these results suggest an inter‐subunit pathway for redox signal transmission from PAS1 that propagates from core to the surface in a conformation‐dependent manner requiring a flexible dimer interface.
Effects of Type I Protein Kinase A Modulation on the T Cell Distal Pole Complex
Authors: Mosenden R. , Moltu K. , Ruppelt A. , Berge T. , Taskén K. 
Published: August 2011

AbstractThe distal pole complex (DPC) assembles signalling proteins at the T cell pole opposite the immunological synapse (IS) and is thought to facilitate T cell activation by sequestering negative regulatory molecules away from the T cell receptor‐proximal signalling machinery. Here, we report the translocation of type I protein kinase A (PKA) to the DPC in a fraction of T cells following activation and the localization of type I PKA with known components of the DPC. We propose that sequestration of type I PKA and concomitant loss of cAMP‐mediated negative regulation at the IS may be necessary to allow full T cell activation. Moreover, composition of the DPC appears to be modulated by type I PKA activity, as the antagonist Rp‐8‐Br‐cAMPS inhibited translocation of type I PKA and other DPC proteins.