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Diazotrophs Show Signs of Restoration in Amazon Rain Forest Soils with Ecosystem Rehabilitation.
Biological nitrogen fixation can be an important source of nitrogen in tropical forests that serve as a major CO2 sink. Extensive deforestation of the Amazon is known to influence microbial communities and the biogeochemical cycles they mediate. However, it is unknown how diazotrophs (nitrogen-fixing microorganisms) respond to deforestation and subsequent ecosystem conversion to agriculture, as well as whether they can recover in secondary forests that are established after agriculture is abandoned. To address these knowledge gaps, we combined a spatially explicit sampling approach with high-throughput sequencing of nifH genes. The main objectives were to assess the functional distance decay relationship of the diazotrophic bacterial community in a tropical forest ecosystem and to quantify the roles of various factors that drive the observed changes in the diazotrophic community structure. We observed an increase in local diazotrophic diversity (α-diversity) with a decrease in community turnover (β-diversity), associated with a shift in diazotrophic community structure as a result of the forest-to-pasture conversion. Both diazotrophic community turnover and structure showed signs of recovery in secondary forests. Changes in the diazotrophic community were primarily driven by the change in land use rather than differences in geochemical characteristics or geographic distances. The diazotroph communities in secondary forests resembled those in primary forests, suggesting that at least partial recovery of diazotrophs is possible following agricultural abandonment.IMPORTANCE The Amazon region is a major tropical forest region that is being deforested at an alarming rate to create space for cattle ranching and agriculture. Diazotrophs (nitrogen-fixing microorganisms) play an important role in supplying soil N for plant growth in tropical forests. It is unknown how diazotrophs respond to deforestation and whether they can recover in secondary forests that establish after agriculture is abandoned. Using high-throughput sequencing of nifH genes, we characterized the response of diazotrophs' β-diversity and identified major drivers of changes in diazotrophs from forest-to-pasture and pasture-to-secondary-forest conversions. Studying the impact of land use change on diazotrophs is important for a better understanding of the impact of deforestation on tropical forest ecosystem functioning, and our results on the potential recovery of diazotrophs in secondary forests imply the possible restoration of ecosystem functions in secondary forests
Making a Third Space for Student Voices in Two Academic Libraries
When we think of voices in the library, we have tended to think of them as disruptive, something to control and manage for the sake of the total library environment. The stereotype of the shushing librarian pervades public perception, creating expectations about the kinds of spaces libraries want to create. Voices are not always disruptive, however. Indeed, developing an academic voice is one of the main challenges facing incoming university students, and libraries can play an important role in helping these students find their academic voices. Two initiatives at two different academic libraries are explored here: a Secrets Wall, where students are invited to write and share a secret during exam time while seeing, reading, commenting on the secrets of others; and a librarian and historian team-taught course called History on the Web, which brings together information literacy and the study of history in the digital age. This article examines both projects and considers how critical perspectives on voice and identity might guide our instructional practices, helping students to learn to write themselves into the university. Further, it describes how both the Secrets Wall and the History on the Web projects intentionally create a kind of “Third Space” designed specifically so students can enter it, negotiate with it, interrogate it, and eventually come to be part of it
Making a Third Space for Student Voices in Two Academic Libraries
When we think of voices in the library, we have tended to think of them as disruptive, something to control and manage for the sake of the total library environment. The stereotype of the shushing librarian pervades public perception, creating expectations about the kinds of spaces libraries want to create. Voices are not always disruptive, however. Indeed, developing an academic voice is one of the main challenges facing incoming university students, and libraries can play an important role in helping these students find their academic voices. Two initiatives at two different academic libraries are explored here: a Secrets Wall, where students are invited to write and share a secret during exam time while seeing, reading, commenting on the secrets of others; and a librarian and historian team-taught course called History on the Web, which brings together information literacy and the study of history in the digital age. This article examines both projects and considers how critical perspectives on voice and identity might guide our instructional practices, helping students to learn to write themselves into the university. Further, it describes how both the Secrets Wall and the History on the Web projects intentionally create a kind of “Third Space” designed specifically so students can enter it, negotiate with it, interrogate it, and eventually come to be part of it
Making a Third Space for Student Voices in Two Academic Libraries
The article examines initiatives including an activity Secrets Wall in which students secretly write secret during exam times and and History on the Web, librarian and historian team-taught course. Topics discussed include creation of third space for student voices, secrets wall offered at the University of Iowa Main Library to help students in final exam and secret wall as a third space for students to offer outlet for authentic self-expression and dialogic information
Colorectal cancer screening: Why immunochemical fecal occult blood tests may be the best option
Abstract Background:There are many test options available for colorectal cancer screening. The choice of test relates to the objectives of those offering or considering screening. Discussion:While all screening programs aim to detect disease early in order to improve the length and/or quality of life for the individual, some organizations and individuals prefer screening tests that offer the opportunity for cancer prevention. Others favor maximizing participation or the opportunity for shared decision-making, including discussion of information on test quality and availability. We propose three additional objectives for screening: minimizing harms, optimizing economic efficiency and maximizing equity of access to screening. Summary:Applying these objectives to colorectal cancer screening, we advocate the use of immunochemical FOBTs as the preferred screening strategy, as it satisfies all three of these important objectives. Keywords:Screening objectives, Colorectal cancer, Fecal occult blood testing, Harm minimization, Equity, Economic efficiency, Prevention, Participatio
The botanical biofiltration of VOCs with active airflow: is removal efficiency related to chemical properties?
© 2019 Elsevier Ltd Botanical biofiltration using active green walls is showing increasing promise as a viable method for the filtration of volatile organic compounds (VOCs) from ambient air; however there is a high level of heterogeneity reported amongst VOC removal efficiencies, and the reasons for these observations have yet to be explained. Comparisons of removal efficiencies amongst studies is also difficult due to the use of many different VOCs, and systems that have been tested under different conditions. The current work describes a procedure to determine whether some of these differences may be related to the chemical properties of the VOCs themselves. This work used an active green wall system to test the single pass removal efficiency (SPRE) of nine different VOCs (acetone, benzene, cyclohexane, ethanol, ethyl acetate, hexane, isopentane, isopropanol and toluene) and explored which chemical properties were meaningful predictor variables of their biofiltration efficiencies. Ethanol was removed most efficiently (average SPRE of 96.34% ± 1.61), while benzene was least efficiently removed (average SPRE of 19.76% ± 2.93). Multiple stepwise linear regression was used to determine that the dipole moment and molecular mass were significant predictors of VOC SPRE, in combination accounting for 54.6% of the variability in SPREs amongst VOCs. The octanol water partition coefficient, proton affinity, Henry's law constant and vapour pressure were not significant predictors of SPRE. The most influential predictor variable was the dipole moment, alone accounting for 49.8% of the SPRE variability. The model thus allows for an estimation of VOC removal efficiency based on a VOC's chemical properties, and supports the idea that system optimisation could be achieved through methods that promote both VOC partitioning into the biofilter's aqueous phase, and substrate development to enhance adsorption.
Timing storytime to maximize children\u27s ability to retain new vocabulary
\ua9 2021 The AuthorsShared storybook reading is a key aid to vocabulary acquisition during childhood. However, word learning research has tended to use unnaturalistic (explicit) training regimes. Using a storybook paradigm, we examined whether children (particularly those with weaker vocabularies) are more likely to retain new words if they learn them closer to sleep. Parents read their children (5- to 7-year-olds; N = 237) an alien adventure story that contained 12 novel words with illustrations at one of two training times: at bedtime or 3–5 h before bedtime. Using online tasks, parents tested their children\u27s ability to recall the new words (production) and associate them with pictures (comprehension) immediately after hearing the story and again the following morning. As hypothesized, we replicated two findings. First, children showed overnight improvements in their ability to produce and comprehend new words when tested again the next day. Second, children with better existing vocabulary knowledge showed larger overnight gains in new word comprehension. Counter to expectations, overnight gains in comprehension were larger if the story was read 3–5 h before bedtime rather than at bedtime. These ecologically valid findings are consistent with theories that characterize word learning as a prolonged process supported by mechanisms such as consolidation and retrieval practice, with existing vocabulary knowledge acting as an important source of variability in retention. The findings provide preliminary evidence that encountering new words in stories later in the day (but not too close to sleep) may help to harness vocabulary growth and may be more beneficial than leaving shared storybook reading just for bedtime
Gender Differences in Diabetes Attitudes and Adherence
This study focused on three questions: Is there a difference in men's and women's diabetes attitudes? Do health professionals give different recommendations to men and women? Is there a difference between men and women in care adherence? A total of 1201 patients with diabetes were surveyed; 65% of these patients were women. Differences in diabetes attitudes (three of seven attiticdes) were most evident between men and women with insulin-dependent diabetes mellitus (IDDM). No differences were found in the attitudes of men and women with non-insulin-dependent diabetes mellitus (NIDDM) using insulin, and only one attitude was different for patients with NIDDM not using insulin. Few differences were observed in the recommendations given by health professionals to men and women. Gender differences in adherence to the components of self-care also were minimal. These findings may indicate that there are many similarities in the reactions of men and women who have been diagnosed with diabetes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69143/2/10.1177_014572179502100605.pd
Angiogenic regulatory influence of extracellular matrix deposited by resting state asthmatic and non‐asthmatic airway smooth muscle cells is similar
The extracellular matrix (ECM) is the tissue microenvironment that regulates the characteristics of stromal and systemic cells to control processes such as inflammation and angiogenesis. Despite ongoing anti-inflammatory treatment, low levels of inflammation exist in the airways in asthma, which alters ECM deposition by airway smooth muscle (ASM) cells. The altered ECM causes aberrant behaviour of cells, such as endothelial cells, in the airway tissue. We therefore sought to characterize the composition and angiogenic potential of the ECM deposited by asthmatic and non-asthmatic ASM. After 72 hours under non-stimulated conditions, the ECM deposited by primary human asthmatic ASM cells was equal in total protein, collagen I, III and fibronectin content to that from non-asthmatic ASM cells. Further, the matrices of non-asthmatic and asthmatic ASM cells were equivalent in regulating the growth, activity, attachment and migration of primary human umbilical vein endothelial cells (HUVECs). Under basal conditions, asthmatic and non-asthmatic ASM cells intrinsically deposit an ECM of equivalent composition and angiogenic potential. Previous findings indicate that dysregulation of the airway ECM is driven even by low levels of inflammatory provocation. This study suggests the need for more effective anti-inflammatory therapies in asthma to maintain the airway ECM and regulate ECM-mediated aberrant angiogenesis
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