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Hsiehchen  David  Espinoza  Magdalena  Hsieh  Antony 《Scientometrics》2018,117(1):391-407
Scientometrics - The expanding presence of multinational research teams highlights the importance of characterizing the outcomes of international collaboration. Herein, we characterize the...  相似文献   
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Total volatile basic nitrogen (TVB-N) as a measure of protein degradation and total microbial counts or stored raw mackerel (Trachurus murphy), which had been treated with chemical preservatives, were compared with the TVB-N and microbial counts of untreated fish. In unpreserved fish, decomposition of fish protein was rapid. Treatment of mackerel with acetic (1000-5000 μg kg?1), which was the most effective of the parameters studied, approximately halved the rate of increase in TVB-N compared with the untreated samples. Changes in the total microbial counts presented a similar trend.  相似文献   
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Alzheimer’s disease (AD) is the most common neurodegenerative disease worldwide. Histopathologically, AD presents with two hallmarks: neurofibrillary tangles (NFTs), and aggregates of amyloid β peptide (Aβ) both in the brain parenchyma as neuritic plaques, and around blood vessels as cerebral amyloid angiopathy (CAA). According to the vascular hypothesis of AD, vascular risk factors can result in dysregulation of the neurovascular unit (NVU) and hypoxia. Hypoxia may reduce Aβ clearance from the brain and increase its production, leading to both parenchymal and vascular accumulation of Aβ. An increase in Aβ amplifies neuronal dysfunction, NFT formation, and accelerates neurodegeneration, resulting in dementia. In recent decades, therapeutic approaches have attempted to decrease the levels of abnormal Aβ or tau levels in the AD brain. However, several of these approaches have either been associated with an inappropriate immune response triggering inflammation, or have failed to improve cognition. Here, we review the pathogenesis and potential therapeutic targets associated with dysfunction of the NVU in AD.  相似文献   
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Alzheimer’s disease (AD) is a neurodegenerative disease, characterized histopathologically by intra-neuronal tau-related lesions and by the accumulation of amyloid β-peptide (Aβ) in the brain parenchyma and around cerebral blood vessels. According to the vascular hypothesis of AD, an alteration in the neurovascular unit (NVU) could lead to Aβ vascular accumulation and promote neuronal dysfunction, accelerating neurodegeneration and dementia. To date, the effects of insoluble vascular Aβ deposits on the NVU and the blood–brain barrier (BBB) are unknown. In this study, we analyze different Aβ species and their association with the cells that make up the NVU. We evaluated post-mortem AD brain tissue. Multiple immunofluorescence assays were performed against different species of Aβ and the main elements that constitute the NVU. Our results showed that there are insoluble vascular deposits of both full-length and truncated Aβ species. Besides, insoluble aggregates are associated with a decrease in the phenotype of the cellular components that constitute the NVU and with BBB disruption. This approach could help identify new therapeutic targets against key molecules and receptors in the NVU that can prevent the accumulation of vascular fibrillar Aβ in AD.  相似文献   
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Engineering reactive materials is an ever present goal in the energetics community. The desire is to have energetics configured in such a manner that performance is tailored and energy delivery can be targeted. Additive manufacturing (3‐D printing) is one area that could significantly improve our capabilities in this area, if adequate formulations are developed. In this paper, fluoropolymer based reactive inks are developed with micron (mAl) and nanoscale aluminum (nAl) serving, as the fuel at high solids loading (up to 67 wt%) and their viscosity required for 3‐D printing is detailed. For the pen‐type technique and valves used in this work, it is required to have viscosities on the order of 104–105 cP. For printed traces with apparent diameters under <500 μm, the combustion velocities for both micron and nano scale aluminum formulations, are approximately identical: 30 ± 3 versus 32 ± 2 mm s?1, respectively. Further increasing the apparent diameter is shown to increase the combustion velocity in the case of the nanoscale aluminum formulation by four‐fold over that of the micron scale aluminum formulation, but it plateaus as it approaches an apparent diameter of 2 mm. The results suggest with proper architecture that tailorable combustion rates and energy delivery are feasible.
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Traceability is recognized to be important for supporting agile development processes. However, after analyzing many of the existing traceability approaches it can be concluded that they strongly depend on traditional development process characteristics. Within this paper it is justified that this is a drawback to support adequately agile processes. As it is discussed, some concepts do not have the same semantics for traditional and agile methodologies. This paper proposes three features that traceability models should support to be less dependent on a specific development process: (1) user-definable traceability links, (2) roles, and (3) linkage rules. To present how these features can be applied, an emerging traceability metamodel (TmM) will be used within this paper. TmM supports the definition of traceability methodologies adapted to the needs of each project. As it is shown, after introducing these three features into traceability models, two main advantages are obtained: 1) the support they can provide to agile process stakeholders is significantly more extensive, and 2) it will be possible to achieve a higher degree of automation. In this sense it will be feasible to have a methodical trace acquisition and maintenance process adapted to agile processes.  相似文献   
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The Australian lungfish is an endangered native species currently protected under various state, federal and international agreements. Scarce information on their early life history is available due to the absence of juveniles collected in the wild. This has led to concerns about the sustainability of the species and become a driver for the conservation effort for Australian lungfish. This study aimed to consolidate knowledge on the critical hydraulic habitat requirements of this species within a water resource management context. In this study, spawning of Australian lungfish was found to be a seasonal strategy that is highly reliant on a variable low‐flow regime within riverine habitat. Suitable conditions for spawning were characterized by small flow events in early‐to‐mid spring when water temperatures are between 18 and 28 °C, leading to oviposition on short dense macrophytes in shallow water. Importantly, many of the key environmental factors driving the ecological response are manageable through existing water resource infrastructure. Specifically, releases from water storages within the current distribution of Australian lungfish should mimic the natural inflow and temperature regime within the spawning period, and also provide suitable riverine habitat within projected full supply limits. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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