584 research outputs found
Parts verification for multi-level-dependent demand manufacturing systems: a recognition and classification structure
This research has developed and implemented a part recognition and classification structure to execute parts verification in a multi-level dependent demand manufacturing system. The part recognition algorithm enables the parent and child relationship between parts to be recognised in a finite-capacitated manufacturing system. This algorithm was developed using SIMAN simulation language and implemented in a multi-level dependent demand manufacturing simulation model. The part classification structure enables the modelling of a multi-level dependent demand manufacturing between parts to be carried out effectively. The part classification structure was programmed using Visual Basic Application (VBA) and was integrated to the work-to-list generated from a simulated MRP model. This part classification structure was then implemented in the multi-level dependent demand manufacturing simulation model. Two stages of implementation, namely parameterisation and execution, of the part recognition and classification structure were carried out. A real case study was used and five detail steps of execution were processed. Simulation experiments and MRP were run to verify and validate the part recognition and classification structure. The results led to the conclusion that implementation of the recognition and classification structure has effectively verified the correct parts and sub-assemblies used for the correct product and order. No parts and sub-assemblies shortages were found, and the quantity required was produced. The scheduled release for some orders was delayed due to overload of the required resources. When the loading is normal, all scheduled release timing is adhered to. The recognition and classification structure has a robust design; hence it can be easily adapted to new systems parameter to study a different or more complex case
Feeding and oral hygiene habits of preschool children in Hong Kong and their caregivers' dental knowledge and attitudes
Objectives. This study was designed to gather data on infant feeding habits and oral hygiene practices of Hong Kong preschool children, on the dental knowledge and attitudes of their caregivers and on the oral health status of the same group of children. Design. Cross-sectional study. Sample and methods. Data was gathered for a total of 369 boys and 297 girls (207 1-year-olds, 269 2-year-olds and 190 3-year-olds) with a mean age of 20-19 (± 0.38) months. Information related to children attending six randomly selected Maternity and Child Health Centres. It was obtained by examining the children and by interviewing the attending caregivers and completing a questionnaire. Each child was given an oral examination using a torch, disposable mirror and wooden tongue spatula. Results. Only 7% of the children were exclusively breast-fed. More than 98% (656/666) of infants used a nursing bottle for at least some drinks. Over 62% (411/656) had used a nursing bottle to take fluids other than water and infant formula. At bedtime, 56% (361/656) were given a nursing bottle prior to sleep and 96% (340/361) of these bottles contained formula milk. Of these children, only 37% (131/361) finished the contents of the bottle before falling asleep. Over 73% (139/190) of the children continued to use a feeding bottle after 2 years of age. Non-nutritive sucking habits were practised by 35.6% (237/666) of the children. Visible plaque, on the labial surface of at least two maxillary incisors, was found in 19.5% (120/615) of the children. Oral cleansing habits were practised for 66.2% (441/666) of the children. Toothbrushing habits were reported for 42.3% (260/615) of the dentate children, of whom 19% (49/260) had their teeth brushed twice daily. Toothpaste was used by 49.23% (128/260) of the children and 57.3% (149/260) brushed their own teeth. Caries was seen in 7.6% of the infants (47/615). Of the caregivers, 67.7% said they did not think carious primary teeth needed to be restored. Among the mothers, 12.6% (43/342) did not know the oral condition of their child. Reportedly, 82% (417/510) and 87.5% (446/510) of the mothers had not received any oral health care information during the ante- or postnatal periods. Nearly all, 97%, of the respondents said that they would like to receive more information on oral health care.postprin
Cyp26b1 mediates differential regulation of RA signaling in neural progenitor populations along the anteriorposterior axis of the adult spinal cord
Poster Session - Neural Regeneration: no. 64DMM 2011 entitled: Re-engineering Regenerative MedicineNeural stem cells from the adult subventricular zone (SVZ) are highly heterogeneous, with their position of origin being a key factor in determining the neuronal subtype they can give rise to. Whether this diversity extends to other regions in the adult CNS has not been demonstrated. In vitro studies with directed neuronal differentiation of ES cells suggest that subtype specification may be regulated by the positional identity present in the ES‐derived cell, since altering the positional identity leads to corresponding changes in motor neuron subtype. This limited plasticity suggests the position identity of the original stem cell source is a critical factor for the generation of the desired neuronal subtype. The adult spinal cord consists of endogenous stem/progenitor cells which are …postprin
Cyp26b1 mediates differential neurogenicity in axial-specific populations of adult spinal cord progenitor cells
Utilization of endogenous adult spinal cord progenitor cells (SCPCs) for neuronal regeneration is a promising strategy for spinal cord repair. To mobilize endogenous SCPCs for injury repair, it is necessary to understand their intrinsic properties and to identify signaling factors that can stimulate their neurogenic potential. In this study, we demonstrate that adult mouse SCPCs express distinct combinatorial Hox genes and exhibit axial-specific stem cell properties. Lumbar-derived neurospheres displayed higher primary sphere formation and greater neurogenicity compared with cervical- and thoracic-derived neurospheres. To further understand the mechanisms governing neuronal differentiation of SCPCs from specific axial regions, we examined the neurogenic responses of adult SCPCs to retinoic acid (RA), an essential factor for adult neurogenesis. Although RA is a potent inducer of neuronal differentiation, we found that RA enhanced the generation of neurons specifically in cervical- but not lumbar-derived cells. We further demonstrate that the differential RA response was mediated by the RA-degrading enzyme cytochrome P450 oxidase b1 Cyp26b1. Lumbar cells express high levels of Cyp26b1 and low levels of the RA-synthesizing enzyme retinaldehyde dehydrogenase Raldh2, resulting in limited activation of the RA signaling pathway in these cells. In contrast, low Cyp26b1 expression in cervical spinal cord progenitor cells allows RA signaling to be readily activated upon RA treatment. The intrinsic heterogeneity and signaling factor regulation among adult SCPCs suggest that different niche factor regimens are required for site-specific mobilization of endogenous SCPCs from distinct spatial regions of the spinal cord for injury repair.published_or_final_versio
A conceptual framework for assessing the ecosystem service of waste remediation: In the marine environment
In the marine environment, the ecosystem service of Waste Remediation (WR) enables humans to utilise the natural functioning of ecosystems to process and detoxify a large number of waste products and therefore avoid harmful effects on human wellbeing and the environment. Despite its importance, to date the service has been poorly defined in ecosystem service classifications and rarely valued or quantified. This paper therefore addresses a gap in the literature regarding the application of this key, but poorly documented ecosystem service. Here we present a conceptual framework by which the ecosystem service of WR can be identified, placed into context within current ecosystem classifications and assessed. A working definition of WR in the marine context is provided as is an overview of the different waste types entering the marine environment. Processes influencing the provisioning of WR are categorised according to how they influence the input, cycling/detoxification, sequestration/storage and export of wastes, with operational indicators for these processes discussed. Finally a discussion of the wider significance of the service of WR is given, including how we can maximise the benefits received from it. It is noted that many methods used in the assessment, quantification and valuation of the service are currently hampered due to the benefits of the service often not being tangible assets set in the market and/or due to a lack of information surrounding the processes providing the service. Conclusively this review finds WR to be an under researched but critically important ecosystem service and provides a first attempt at providing operational guidance on the long term sustainable use of WR in marine environments
Exploring precision polymers to fine-tune magnetic resonance imaging properties of iron oxide nanoparticles
The use of bio-polymers as stabilising agents for iron oxide-based negative magnetic resonance imaging (MRI) contrast agents has become popular in recent years, however the wide polydispersity of biologically-derived and commercially available polymers limits the ability to produce truly tuneable and reproducible behaviour, a major challenge in this area. In this work, stable colloids of iron oxide nanoparticles were prepared utilising precision-engineered bio-polymer mimics, poly(2-acrylamido-2-methylpropane sodium sulfonate) (P(AMPS)) polymers, with controlled narrow polydispersity molecular weights, as templating stabilisers. In addition to producing magnetic colloids with excellent MRI contrast capabilities (r2 values reaching 434.2 mM−1 s−1 at 25 °C and 23 MHz, several times higher than similar commercial analogues), variable field relaxometry provided unexpected important insights into the dynamic environment of the hydrated materials, and hence their exceptional MRI behaviour. Thanks to the polymer’s templating backbone and flexible conformation in aqueous suspension, nanocomposites appear to behave as “multi-core” clustered species, enhancing interparticle interactions whilst retaining water diffusion, boosting relaxation properties at low frequency. This clustering behaviour, evidenced by small-angle X-ray scattering, and strong relaxometric response, was fine-tuned using the well-defined molecular weight polymer species with precise iron to polymer ratios. By also showing negligible haemolytic activity, these nanocomposites exhibit considerable potential for MRI diagnostics
Improved Diagnosis and Management of Paediatric Renal Transplant Recipients Using the Banff 2013 Histopathological Classification
Introduction: Since the publication of the 2013 Banff classification, adult studies have shown evidence of improved prognosis using the new histopathological criteria. Our study assesses for the first time the impact of the new classification on the diagnosis of acute antibody-mediated rejection (AMR) in paediatric renal transplant recipients (pRTR). /
Methods: This single-centre study is a retrospective evaluation of 56 paediatric post-transplant de novo DSA-positive patients who had a percutaneous renal transplant biopsy due to renal allograft dysfunction from January 2006 to March 2012. Their biopsies were re-scored by a solitary specialist trained in 2013 Banff classification. The results were compared with previous classification as per 2003/2007 Banff criteria with results presented as range (median). /
Results: At the time of biopsy, pRTR were aged 1.6 - 17.5 (median 14.9) years old with 412 - 2735 mean fluorescence intensity (MFI; maximal at 713 - 31,625; median 3466 and 4809). Following the 2013 Banff classification, there was a total of 5 cases of acute AMR compared to one confirmed and one suspicious AMR with the 2003/2007 Banff classification (with no change in the remaining 51 patients’ classification). Consequently, 5.3% (3 of 56) patients would have been diagnosed with T-cell mediated rejection with suboptimal treatment. There was an overall 70% (48 - 112%) decrease in the renal allograft function in the 6 months follow-up period after aggressive treatment for acute AMR and 2 of 3 patients had further rejection episodes in the following year. /
Conclusion: This research supports the new Banff 2013 classification as a more precise classification in pRTR in the diagnosis of AMR with 5% of patients being correctly diagnosed and managed with improvement in renal allograft function
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Human Side of Collaborative Partnerships
The research on collaborative partnerships has accumulated a vast body of knowledge, which has assisted us with comprehending several complex organizational phenomena, including mergers and acquisitions, strategic alliances, joint ventures, and entrepreneurial partnerships. Yet, the existing studies have not paid sufficient attention to the human side factors. We join the current conversation within the microfoundations perspective of management and organization studies by suggesting that investigating the human side factors as the microfoundations of collaborative partnerships can advance our collective understanding of the phenomena in important ways. This article has three general objectives. First, we show that collaborative partnerships have been a long-standing issue in management and organization studies and provide an overview of the puzzles that informed and motivated this special issue. Second, we highlight the key insights and contributions of the articles included in this special issue by reviewing their theoretical underpinnings, methodological approaches, and findings. Finally, we outline a future research agenda on the human side of collaborative partnerships that can help advance management and organization studies
Inclusion of condition in natural capital assessments is critical to the implementation of marine nature-based solutions
Current approaches to measure ecosystem services (ES) within natural capital (NC) and nature-based solutions (NbS)
assessments are generally coarse, often using a single figure for ecosystem services (e.g., nutrient remediation or blue carbon sequestration) applied to the local or national habitat stock, which fails to take account of local ecosystem con�ditions and regional variability. As such, there is a need for improved understanding of the link between habitat con�dition and ES provision, using comparable indicators in order to take more informed management decisions. Here the
UK, Solent Marine Sites (SEMS) is used as a case study system to demonstrate how Water Framework Directive (WFD)
‘ecological status’ and other indicators of ecosystem condition (state or quality) can be coupled with habitat extent information to deliver a more precise locally-tailored NC approach for active coastal and marine habitat restoration. Habitat extent and condition data are collected for seven NbS relevant coastal habitats (littoral sediment, matforming green macroalgae, subtidal sediment, saltmarsh, seagrass, reedbeds and native oyster beds). The workflow includes: 1) biophysical assessment of regulatory ES; 2) monetary valuation; and 3) compilation of future scenarios of habitat restoration and creation. The results indicate that incorporating classifications by condition indices into local NC extent accounts improved ES benefits by 11–67%. This suggests that omitting condition from NC assessments could lead to undervaluation of ES benefits. Future scenarios of restoration in the SEMS also show that the additional regulatory benefits of reaching ‘Good’ ecological status are £376 million annually, but could be as much as £1.218 billion if ‘High‘status and all habitat creation targets were met. This evidence of the potential value of restoration and importance of including condition indices in assessments is highly relevant to consider when investing in water ecosystems conservation and restoration as called for by the UN Decade on Ecosystem Restoration (2021−2030), and more generally in global nutrient neutrality and blue carbon policy strategies
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Servitization in mergers and acquisitions: Manufacturing firms venturing from emerging markets into advanced economies
The British Academy and Sino-British Fellowship Trus
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