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61.
Family mealtimes can be important for supporting children''s healthy development, yet the emotional context of mealtimes can vary considerably, likely impacting their overall success and enjoyment. Yet, despite having an important role, little is known about how parents emotionally experience mealtimes with their family. The first aim of the current study was to assess the factor structure of a novel self‐report measure to assess parents’ emotional responses experienced during family mealtimes (Mealtime Emotions Measure for Parents; MEM‐P). The second aim was to examine relationships between maternal mealtime emotions and their food parenting practices. Mothers of children aged between 1.5 and 6 years participated in this study. Mothers were invited to complete an online questionnaire measuring family mealtime emotions, anxiety, depression and food parenting practices. Exploratory factor analysis produced a three‐factor solution comprising both positive and negative emotion subscales: MEM‐P Efficacy; MEM‐P Anxiety; MEM‐P Stress and Anger. Mothers'' positive mealtime emotions (mealtime efficacy) were related to greater use of practices promoting autonomy, providing a healthy home food environment, and modelling healthy eating. Higher anxiety about mealtimes was related to greater reports of child control over eating, and mealtime stress and anger was associated with greater use of food to regulate emotions. These findings highlight novel relationships between how mothers emotionally experience family mealtimes and the food parenting practices they use with their children. It is important to develop resources to help promote positive maternal experiences of family mealtimes and food‐based interactions. 相似文献
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Alamelu Ramamurthi M.D. Natesa G. Pandian M.D. Michael S. Kiernan M.D. Hannah Lee M.D. David DeNofrio M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1139-1141
A patient with eroded tricuspid and pulmonic valves, who eventually developed elevated right atrial and systemic venous pressure that led to hepatic cirrhosis and recurrent pleural effusion, is presented. The complex issues involved over a long period in this patient, who ultimately required combined heart and liver transplant, are discussed. 相似文献
64.
Hannah J. Broadley Kate L. Buckman Deenie M. Bugge Celia Y. Chen 《Archives of environmental contamination and toxicology》2013,65(4):765-778
The former Callahan Mine Site in Brooksville, ME, is an open-pit, hardrock mine site in an intertidal system, thus providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Copper, zinc, cadmium, and lead concentrations in sediment, whole water, and Atlantic killifish (Fundulus heteroclitus) were evaluated at sites in Goose Pond (GP; Callahan Mine Site) and at reference sites. The metal concentrations of sediment, water, and fish were spatially distinct and significantly greater at the mine site than in the reference estuary. Sediment concentrations were particularly elevated and were above probable effects levels for all four metals adjacent to the tailings pile. Even in this well-mixed system, water metal concentrations were significantly elevated adjacent to the tailings pile, and concentrations of Cu and Zn were above ambient water-quality criteria for chronic marine exposure. Neither organic matter in the sediment nor salinity or pH of the water explained the metal concentrations. Adjacent to the tailings pile, killifish metal body burdens were elevated and were significantly related to both sediment and aqueous concentrations. In conclusion, (1) the contaminated sediment and seepage from the tailings impoundment and waste rock pile no. 3 create a continual flux of metals into the water column, (2) the metals are bioavailable and bioconcentrating as evident in the killifish tissue concentrations, and (3) Callahan Mine is directly affecting metal bioaccumulation in fauna residing in the GP estuary and, potentially, in Penobscot Bay by the way of “trophic nekton relay.” 相似文献
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Endogenous polyphenolic compounds in cacao impart both bitter and astringent characteristics to chocolate confections. While an increase in these compounds may be desirable from a health perspective, they are generally incongruent with consumer expectations. Traditionally, chocolate products undergo several processing steps (e.g., fermentation and roasting) that decrease polyphenol content, and thus bitterness. The objective of this study was to estimate group rejection thresholds for increased content of cocoa powder produced from under-fermented cocoa beans in a semisweet chocolate-type confection. The group rejection threshold was equivalent to 80.7% of the non-fat cocoa solids coming from the under-fermented cocoa powder. Contrary to expectations, there were no differences in rejection thresholds when participants were grouped based on their self-reported preference for milk or dark chocolate, indicating that these groups react similarly to an increase in high cocoa flavanol containing cocoa powder. 相似文献
67.
Purpose: The Nottingham Extended Activities of Daily Living (EADL) scale is a popular outcome measure in stroke research. Its psychometric properties have not been tested in other conditions. Methods: EADL has been measured before, three and six months after hip arthroplasty. A sample was retested for reliability. Comparisons were made with the SF-36 and London Handicap Scale. Standard psychometric parameters were calculated. Results: The sub-scales and total score were approximately unidimensional on factor analysis and Cronbach's alpha, but did not form an adequate hierarchical (Guttmann) scale. Associations with other scales were in the expected direction and of approximately the expected strength, supporting concurrent and construct validity. Reliability was good. Responsiveness was poor compared with the other scales. Conclusions: The EADL is valid in patients with arthritis of the hip, and is reliable. However, it underestimates the size of health gain after hip arthroplasty compared with other scales. 相似文献
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Anam Tariq Hannah Kim Hashim Abbas Gregory M. Lucas Mohamed G. Atta 《Expert opinion on pharmacotherapy》2021,22(1):69-82
ABSTRACT
Introduction
Since the developmentof combined antiretroviral therapy (cART), HIV-associated mortality and the incidence of HIV-associated end-stage kidney disease (ESKD) has decreased. However, in the United States, an increase in non-HIV-associated kidney diseases within the HIV-positive population is expected. 相似文献70.
Thomas V. Harwood Esthefani G. Zuniga HoJun Kweon Douglas D. Risser 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(12)
Motility is ubiquitous in prokaryotic organisms including the photosynthetic cyanobacteria where surface motility powered by type 4 pili (T4P) is common and facilitates phototaxis to seek out favorable light environments. In cyanobacteria, chemotaxis-like systems are known to regulate motility and phototaxis. The characterized phototaxis systems rely on methyl-accepting chemotaxis proteins containing bilin-binding GAF domains capable of directly sensing light, and the mechanism by which they regulate the T4P is largely undefined. In this study we demonstrate that cyanobacteria possess a second, GAF-independent, means of sensing light to regulate motility and provide insight into how a chemotaxis-like system regulates the T4P motors. A combination of genetic, cytological, and protein–protein interaction analyses, along with experiments using the proton ionophore carbonyl cyanide m-chlorophenyl hydrazine, indicate that the Hmp chemotaxis-like system of the model filamentous cyanobacterium Nostoc punctiforme is capable of sensing light indirectly, possibly via alterations in proton motive force, and modulates direct interaction between the cyanobacterial taxis protein HmpF, and Hfq, PilT1, and PilT2 to regulate the T4P motors. Given that the Hmp system is widely conserved in cyanobacteria, and the finding from this study that orthologs of HmpF and T4P proteins from the distantly related model unicellular cyanobacterium Synechocystis sp. strain PCC6803 interact in a similar manner to their N. punctiforme counterparts, it is likely that this represents a ubiquitous means of regulating motility in response to light in cyanobacteria.Motility is ubiquitous in prokaryotic organisms, including both swimming motility in aqueous environments and twitching or gliding motility on solid surfaces, and enables these organisms to optimize their position in response to various environmental factors. Among the photosynthetic cyanobacteria, surface motility is widespread and facilitates phototaxis to seek out favorable light environments (1, 2), and, for multicellular filamentous cyanobacteria, plays a key role in dispersal as well as the establishment of nitrogen-fixing symbioses with eukaryotes (3) and the formation of supracellular structures (3–5).Current understanding of cyanobacterial surface motility at the molecular level has been informed primarily by studies of two model organisms, the unicellular strain Synechocystis sp. strain PCC6803 (herein Synechocystis) and the filamentous strain Nostoc punctiforme ATCC29133/, where motility is exhibited only by differentiated filaments termed “hormogonia.” Motility in both organisms is powered by a type IV pilus (T4P) system where the ATPases PilB and PilT drive the extension and subsequent retraction, respectively, of pili which adhere to the substrate and pull the cells forward (for review, see ref. PCC731026). In Synechocystis, the T4P motors are distributed throughout the entire cell, allowing a 360 ° range of motion (7), whereas in N. punctiforme they are confined to rings at the cell poles (8), resulting in movement only along the long axis of the filament. Comparative genomics implies that this mechanism of motility is widely conserved among cyanobacteria (9).Both Synechocystis and N. punctiforme employ chemotaxis-like systems to regulate motility. One of these systems, the Hmp chemotaxis-like system of N. punctiforme (3, 10), and its orthologous counterpart, the Pil chemotaxis-like system of Synechocystis (11), includes homologs to the canonical Escherichia coli chemotaxis complex (for review, see ref. 12), including the histidine kinase CheA, the adaptor protein CheW, the response regulator CheY, and the methyl-accepting chemotaxis protein MCP. These systems are essential for motility in their respective organisms and appear to regulate the T4P motors, although there are distinct differences in the phenotypes for inactivation of the components from each. In Synechocystis, null mutations either enhance or reduce the level of surface piliation (11), whereas in N. punctiforme they disrupt the coordinated polarity, but not the overall level of piliation, and affect various other aspects of hormogonium development (3, 10). In N. punctiforme, the subcellular localization of this system has been determined and has been found arrayed in static, bipolar rings similar to the T4P motors (3). However, the signals that are perceived by the MCPs and the precise mechanism by which these systems modulate T4P activity is currently undefined.Recently, an additional component of the Hmp system, HmpF, was characterized (9). HmpF is a predicted coiled-coil protein and is ubiquitous to, but confined within, the cyanobacterial lineage (9). It is essential for accumulation of surface pili and exhibits dynamic, unipolar localization to the leading poles of most cells in hormogonium filaments (9). Based on these findings, a model has been proposed where the localization of HmpF is regulated by the other components of the Hmp system, and in turn, the unipolar accumulation of HmpF leads to the activation of the T4P motors on one side of the cell to facilitate directional movement.A second chemotaxis-like system in each organism, the Ptx system of N. punctiforme (13) and the Pix system of Synechocystis (14, 15), is essential for positive phototaxis. These systems contain MCPs with cyanobacteriochrome sensory domains capable of perceiving light (for review, see ref. 16). Disruption of the Pix system results in negative phototaxis under light conditions that normally produce a positive phototactic response (14). Several other proteins containing cyanobacteriochromes, and one containing a BLUF domain, also modulate phototaxis in Synechocystis (for review, see ref. 6). In N. punctiforme, disruption of the Ptx system abolishes the phototactic response completely, resulting in uniform movement in all directions regardless of the light conditions (13), and there are currently no other proteins reported to modulate phototaxis. More recently, a motile, wild isolate of the model unicellular cyanobacterium Synechococcus elongatus sp. PCC7942 was shown to possess a chemotaxis-like system that modulates phototaxis in a manner similar to that of the N. punctiforme Ptx system (17). How these systems influence T4P activity to facilitate phototaxis is also currently unknown.There is also a substantial body of literature on motility and phototaxis in cyanobacteria, primarily based on observational studies of various filamentous strains, that predates the development of genetically tractable model organisms (for review, see ref. 18). These reports suggested that the photosystems may serve a sensory role in modulating phototaxis and that proton motive force (PMF) powers motility (19, 20), a finding that is inconsistent with the theory that cyanobacteria possess a common T4P-based gliding motor driven by ATP hydrolysis. In this study, we help reconcile this historical data with more recent molecular studies by providing evidence that the Hmp chemotaxis-like system senses light, possibly indirectly through alterations in PMF, and in turn modulates the interaction of HmpF with the T4P base to activate the motors. 相似文献