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991.
Jose P. Garcia-Sabater Julien Maheut Julio J. Garcia-Sabater 《Flexible Services and Manufacturing Journal》2012,24(2):171-209
This paper presents an operations planning scheme based on mathematical programming models (specifically, Mixed-Integer Linear Programming (MILP) models) integrated into a web-enabled Advanced Planning and Scheduling System (APS), developed for and implemented in an engine assembler that supplies the car industry. One objective of this paper is to provide empirical insights into some operations planning characteristics in the automotive industry. The other main objective is to show MILP models and their use to create plans that enable the coordination of different planning levels (mid-term and short-term) and planning domains (procurement, production and distribution). The APS fulfills the requirements of an engine assembler in the automotive sector (namely lean-type constraints and objectives). The system is based on two MILP models, which have been purposely developed together along with their relations. The models presented herein provide a solution that considers supply chain objectives and constraints, and are integrated by means of data and constraints which have proven sufficient to fulfill users?? and stakeholders?? requirements. This case study presents the models?? most relevant aspects and their implementation. 相似文献
992.
Sandal N Jin H Rodriguez-Navarro DN Temprano F Cvitanich C Brachmann A Sato S Kawaguchi M Tabata S Parniske M Ruiz-Sainz JE Andersen SU Stougaard J 《DNA research》2012,19(4):317-323
Model legumes such as Lotus japonicus have contributed significantly to the understanding of symbiotic nitrogen fixation. This insight is mainly a result of forward genetic screens followed by map-based cloning to identify causal alleles. The L. japonicus ecotype 'Gifu' was used as a common parent for inter-accession crosses to produce F2 mapping populations either with other L. japonicus ecotypes, MG-20 and Funakura, or with the related species L. filicaulis. These populations have all been used for genetic studies but segregation distortion, suppression of recombination, low polymorphism levels, and poor viability have also been observed. More recently, the diploid species L. burttii has been identified as a fertile crossing partner of L. japonicus. To assess its qualities in genetic linkage analysis and to enable quantitative trait locus (QTL) mapping for a wider range of traits in Lotus species, we have generated and genotyped a set of 163 Gifu × L. burttii recombinant inbred lines (RILs). By direct comparisons of RIL and F2 population data, we show that L. burttii is a valid alternative to MG-20 as a Gifu mapping partner. In addition, we demonstrate the utility of the Gifu × L. burttii RILs in QTL mapping by identifying an Nfr1-linked QTL for Sinorhizobium fredii nodulation. 相似文献
993.
Genetic structures of the CIMMYT international yield trial targeted to irrigated environments 总被引:1,自引:0,他引:1
Susanne Dreisigacker Hailemichael Shewayrga Jose Crossa Vivi N. Arief Ian H. DeLacy Ravi P. Singh Mark J. Dieters Hans-Joachim Braun 《Molecular breeding : new strategies in plant improvement》2012,29(2):529-541
International yield trials are assembled by CIMMYT to disseminate promising wheat breeding materials worldwide. To assess
the genomic structure and linkage disequilibrium (LD) within this germplasm, wheat lines disseminated during 25 years of the
Elite Spring Wheat Yield Trial (ESWYT) targeted for irrigated environments of the world were genotyped with the high-throughput
Diversity Arrays Technology (DArT) marker system. Analyses of population structure assigned the ESWYT germplasm into five
major sub-populations that are shaped by prominent CIMMYT wheat lines and their descendants. Based on genetic distance, we
concluded that a constant level of genetic diversity was maintained over the years of ESWYT dissemination. Genetic distance
between the individual ESWYT lines significantly increased when the ESWYT were grouped according to the differences in years
of ESWYT dissemination, suggesting a systematic change in allele frequencies over time, most probably due to breeding and
directional selection. By means of multiple regression analyses, 78 markers displaying a significant change in allele frequency
across years were identified and interpreted as an indicator for constant selection. The markers identified were partly associated
with grain yield, leaf, stem, and yellow rust and point to key genomic regions for further investigation. Large numbers of
adjacent DArT marker pairs showed significant LD across the ESWYT population and within each of the five sub-populations identified.
Sub-population differentiation measured by the fixation index and average genetic distance were highly correlated with LD
levels, suggesting that the sub-populations themselves explain much of the LD. 相似文献
994.
995.
Huang X Narayanaswamy R Fenn K Szpakowski S Sasaki C Costa J Blancafort P Lizardi PM 《DNA and cell biology》2012,31(Z1):S2-S10
Treatment with demethylating drugs can induce demethylation and reactivation of abnormally silenced tumor suppressor genes in cancer cells, but it can also induce potentially deleterious loss of methylation of repetitive elements. To enable the observation of unwanted drug effects related to loss of methylation of repetitive DNA, we have developed a novel biosensor capable of reporting changes in DNA accessibility via luminescence, in living cells. The biosensor design comprises two independent modules, each with a polydactyl zinc finger domain fused to a half intein and to a split-luciferase domain that can be joined by conditional protein splicing after binding to adjacent DNA targets. We show that an artificial zinc finger design specifically targeting DNA sequences near the promoter region of the L1PA2 subfamily of Line-1 retroelements is able to generate luminescent signals, reporting loss of epigenetic silencing and increased DNA accessibility of retroelements in human cells treated with the demethylating drugs decitabine or 5-azacytidine. 相似文献
996.
The vaccine global market is currently growing at a rate of 16.52%. Nowadays the vaccine manufacturing industry is limited in the sense that not all vaccine manufacturers have the capacity to execute all the steps necessary to produce a successful product. The biological variation inherent to vaccine manufacturing and the initial investment required to bring a vaccine to the market are some of the factors that discourage vaccine manufacturing initiatives.Given the current global context in vaccine innovation and production, and the increasing participation of vaccine manufacturers from developing countries in global markets, this paper aims to review vaccine manufacturing capacity in Latin American and Caribbean (LAC) countries with specific focus on trends in national or public sector manufacturing, presenting current challenges and future opportunities for the sector in meeting national and regional (LAC) needs.Despite the overall low vaccine manufacturing capacity reported within the LAC region within this paper, it is considered that the relatively high and concentrated capacity that exists within a number of countries, combined with political commitment of all countries within the Region, can provide the necessary platform for the continued development of capacity in vaccine development and manufacture within LAC. 相似文献
997.
Marín PJ Santos-Lozano A Santin-Medeiros F Vicente-Rodriguez G Casajús JA Hazell TJ Garatachea N 《Journal of electromyography and kinesiology》2012,22(3):456-462
The current study examined the effects of whole-body vibration (WBV) on upper and lower body muscle activity during static muscle contractions (squat and bicep curls). The use of WBV accessories such as hand straps attached to the platform and a soft surface mat were also evaluated. Surface electromyography (sEMG) was measured for the medial gastrocnemius (MG), vastus lateralis (VL), and biceps brachii (BB) muscles in fourteen healthy older adults (74.8±4.5 years; mean±SD) with a WBV stimulus at an acceleration of 40 m s(-2) (30 Hz High, 2.5 mm or 46 Hz Low, 1.1 mm). WBV increased lower body (VL and MG) sEMG vs baseline (no WBV) though this was decreased with the use of the soft mat. The addition of the bicep curl with hand straps had no effect on lower body sEMG. WBV also increased BB sEMG vs baseline which was further increased when using the hand straps. There was no upper body effect of the soft mat. This study demonstrates WBV increases both lower and upper body muscle activity in healthy older adults. Moreover, WBV accessories such as hand straps attached to the platform or a soft surface mat may be used to alter exercise intensity. 相似文献
998.
FLASH assembly of TALENs for high-throughput genome editing 总被引:5,自引:0,他引:5
999.
Meiri D Marshall CB Greeve MA Kim B Balan M Suarez F Bakal C Wu C Larose J Fine N Ikura M Rottapel R 《Molecular cell》2012,45(5):642-655
Actin-based stress fiber formation is coupled to microtubule depolymerization through the local activation of RhoA. While the RhoGEF Lfc has been implicated in this cytoskeleton coupling process, it has remained elusive how Lfc is recruited to microtubules and how microtubule recruitment moderates Lfc activity. Here, we demonstrate that the dynein light chain protein Tctex-1 is required for localization of Lfc to microtubules. Lfc residues 139-161 interact with Tctex-1 at a site distinct from the cleft that binds dynein intermediate chain. An NMR-based GEF assay revealed that interaction with Tctex-1 represses Lfc nucleotide exchange activity in an indirect manner that requires both polymerized microtubules and phosphorylation of S885 by PKA. We show that inhibition of Lfc by Tctex-1 is dynein dependent. These studies demonstrate a pivotal role of Tctex-1 as a negative regulator of actin filament organization through its control of Lfc in the crosstalk between microtubule and actin cytoskeletons. 相似文献
1000.
Vladimir E. Martinez-Bello Fabian Sanchis-Gomar Marco Romagnoli Frederic Derbre Mari Carmen Gomez-Cabrera Jose Vi?a 《Journal of physiology and biochemistry》2012,68(4):593-601
The blood O2-carrying capacity is maintained by the O2-regulated production of erythropoietin (Epo), which stimulates the proliferation and survival of red blood cell progenitors. Epo has been thought to act exclusively on erythroid progenitor cells. However, recent studies have identified the erythropoietin receptor (EpoR) in other cells, such as neurons, astrocytes, microglia, heart, cancer cell lines, and skeletal muscle provides evidence for a potential role of Epo in other tissues. In this study we aimed to determine the effect of recombinant human erythropoietin (rHuEpo) on skeletal muscle adaptations such as mitochondrial biogenesis, myogenesis, and angiogenesis in different muscle fibre types. Fourteen male Wistar rats were randomly divided into two experimental groups, and saline or rHuEpo (300?IU) was administered subcutaneously three times a week for 3?weeks. We evaluated the protein expression of intermediates involved in the mitochondrial biogenesis cascade, the myogenic cascade, and in angiogenesis in the oxidative soleus muscle and in the glycolytic gastrocnemius muscle. Contrary to our expectations, rHuEpo significantly hampered the mitochondrial biogenesis pathway in gastrocnemius muscle (PGC-1??, mTFA and cytochrome c). We did not find any effect of the treatment on cellular signals of myogenesis (MyoD and Myf5) or angiogenesis (VEGF) in either soleus or gastrocnemius muscles. Finally, we found no significant effect on the maximal aerobic velocity at the end of the experiment in the rHuEpo-treated animals. Our findings suggest that 3?weeks of rHuEpo treatment, which generates an increase of oxygen carrying capacity, can affect mitochondrial biogenesis in a muscle fibre-specific dependent manner. 相似文献