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31.
Mnica Aguilera Valerio Rossini Ana Hickey Donjete Simnica Fiona Grady Valeria D. Felice Amy Moloney Lauren Pawley Aine Fanning Lorraine McCarthy Siobhan M. OMahony John F. Cryan Ken Nally Fergus Shanahan Silvia Melgar 《International journal of molecular sciences》2021,22(15)
Interactions between the intestinal microbiota, immune system and nervous system are essential for homeostasis in the gut. Inflammasomes contribute to innate immunity and brain–gut interactions, but their role in microbiota–neuro–immune interactions is not clear. Therefore, we investigated the effect of the inflammasome on visceral pain and local and systemic neuroimmune responses after antibiotic-induced changes to the microbiota. Wild-type (WT) and caspase-1/11 deficient (Casp1 KO) mice were orally treated for 2 weeks with an antibiotic cocktail (Abx, Bacitracin A and Neomycin), followed by quantification of representative fecal commensals (by qPCR), cecal short chain fatty acids (by HPLC), pathways implicated in the gut–neuro-immune axis (by RT-qPCR, immunofluorescence staining, and flow cytometry) in addition to capsaicin-induced visceral pain responses. Abx-treatment in WT-mice resulted in an increase in colonic macrophages, central neuro-immune interactions, colonic inflammasome and nociceptive receptor gene expression and a reduction in capsaicin-induced visceral pain. In contrast, these responses were attenuated in Abx-treated Casp1 KO mice. Collectively, the data indicate an important role for the inflammasome pathway in functional and inflammatory gastrointestinal conditions where pain and alterations in microbiota composition are prominent. 相似文献
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Although a substantial proportion of the western population is approaching retirement age, little is known about how they are preparing for the future. Much attention has been paid to the consumption of educational material and retirement wealth in the present literature, but the process of retirement planning has been ignored. S. L. Friedman and E. K. Scholnick's (1997) theoretical model provided the basis for a comprehensive measure of retirement planning. According to their process theory, individuals develop an understanding of the problem, set goals, make a decision to start preparing, and finally undertake the behaviors needed to fulfill their goals. Fifty-two items were developed to assess each stage of the planning process for financial, health, lifestyle, and psychosocial retirement planning. These were tested on a population sample of 1,449 New Zealanders aged 49–60. Confirmatory factor analysis, bivariate correlations, and hierarchical regression provided support for the valid use of the measure. Necessary antecedents, such as the tendency to look to the future, and locus of control were significantly related to the Process of Retirement Planning Scale (PRePS). The PRePS also outperformed retirement planning measures used in the Health and Retirement Study (F. T. Juster & R. Suzman, 1995) after controlling for socioeconomic and psychological variables. This measure will enable social policy makers to determine which stages of retirement planning require support and intervention. The PRePS will also help to determine which domains of retirement planning predict well-being in later life and the factors which differentiate those who are planning from those who are not. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Accounting for wheel–terrain interaction is crucial for navigation and traction control of mobile robots in outdoor environments and rough terrains. Wheel slip is one of the surface hazards that needs to be detected to mitigate against the risk of losing the robot's controllability or mission failure occurring. The open problems in the Terramechanics field addressed are (1) the need for in situ wheel-slippage estimation in harsh environments using low-cost/power and easy to integrate sensors, and (2) removing the need for prior information of the soil, which is not always available. This paper presents a novel slip estimation method that utilizes only two proprioceptive sensors (IMU and wheel encoder) to estimate the wheel slip using deep learning methods. It is experimentally shown to be real-world feasible in outdoor, uneven terrains without prior soil information assumptions. Comparison with previously used machine learning algorithms for continuous and discrete slip estimation problems show more than 9% and 14% improvement in estimation performance, respectively. 相似文献
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This paper describes the inadequacies in the provision for water, sanitation and solid waste collection in nine cities in Africa, Asia and Latin America and discusses the main explanatory factors. These include the quality and capacity of each city's local government, and the nature of its relationship with citizen groups and non-governmental organizations within the city and with governments at provincial/state or national level. The paper highlights the many political constraints on ensuring healthier living and working environments for lower-income groups, including those rooted in local government structures and perceptions, as well as those related to low per capita incomes and poor economic performance. 相似文献
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Fiona C. Meldrum Cedrick O'Shaughnessy 《Advanced materials (Deerfield Beach, Fla.)》2020,32(31):2001068
Many crystallization processes of great importance, including frost heave, biomineralization, the synthesis of nanomaterials, and scale formation, occur in small volumes rather than bulk solution. Here, the influence of confinement on crystallization processes is described, drawing together information from fields as diverse as bioinspired mineralization, templating, pharmaceuticals, colloidal crystallization, and geochemistry. Experiments are principally conducted within confining systems that offer well-defined environments, varying from droplets in microfluidic devices, to cylindrical pores in filtration membranes, to nanoporous glasses and carbon nanotubes. Dramatic effects are observed, including a stabilization of metastable polymorphs, a depression of freezing points, and the formation of crystals with preferred orientations, modified morphologies, and even structures not seen in bulk. Confinement is also shown to influence crystallization processes over length scales ranging from the atomic to hundreds of micrometers, and to originate from a wide range of mechanisms. The development of an enhanced understanding of the influence of confinement on crystal nucleation and growth will not only provide superior insight into crystallization processes in many real-world environments, but will also enable this phenomenon to be used to control crystallization in applications including nanomaterial synthesis, heavy metal remediation, and the prevention of weathering. 相似文献
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Martin G. Shepley Mike Streetly Kevin Voyce Fiona Bamford 《Water and Environment Journal》2009,23(4):263-271
The Shropshire Groundwater Scheme (SGS) is the largest conjunctive use scheme in the United Kingdom. The SGS operates in drought periods, pumping water from the Permo‐Triassic Sandstone aquifer in Shropshire, England to regulate flows in the River Severn, alongside releases from conventional surface water reservoirs. This regulation protects the environment and increases the security of supply of major public water supply abstractions downstream. An important operational consideration is the impact SGS groundwater abstraction has on small streams that rise on the Shropshire Permo‐Triassic Sandstone. Compensation boreholes have been installed to maintain flows during and after the operation of the SGS. This paper shows how a groundwater model of the East Shropshire Permo‐Triassic Sandstone has been used to estimate the required level of compensation flows for recent climatic conditions to optimise the use of the SGS. The catchment wide conditions are included in this analysis by using the results of a large‐scale surface water model of the River Severn. 相似文献