Cover crops have the potential to be agricultural nitrogen (N) regulators that reduce leaching through soils and then deliver N to subsequent cash crops. Yet, regulating N in this way has proven ...difficult because the few cover crop species that are well-studied excel at either reducing N leaching or increasing N supply to cash crops, but they fail to excel at both simultaneously. We hypothesized that mixed species cover crop stands might balance the N fixing and N scavenging capabilities of individual species. We tested six cover crop monocultures and four mixtures for their effects on N cycling in an organically managed maize-soybean-wheat feed grain rotation in Pennsylvania, USA. For three years, we used a suite of integrated approaches to quantify N dynamics, including extractable soil inorganic N, buried anion exchange resins, bucket lysimeters, and plant N uptake. All cover crop species, including legume monocultures, reduced N leaching compared to fallow plots. Cereal rye monocultures reduced N leaching to buried resins by 90% relative to fallow; notably, mixtures with just a low seeding rate of rye did almost as well. Austrian winter pea monocultures increased N uptake in maize silage by 40 kg N ha-1 relative to fallow, and conversely rye monocultures decreased N uptake into maize silage by 40 kg N ha-1 relative to fallow. Importantly, cover crop mixtures had larger impacts on leaching reduction than on maize N uptake, when compared to fallow plots. For example, a three-species mixture of pea, red clover, and rye had similar maize N uptake to fallow plots, but leaching rates were 80% lower in this mixture than fallow plots. Our results show clearly that cover crop species selection and mixture design can substantially mitigate tradeoffs between N retention and N supply to cash crops, providing a powerful tool for managing N in temperate cropping systems.
Accumulating wealth is one of the main concerns for consumers. Higher education is widely associated with higher wealth, but the underlying reasons for this association remain unclear. Using data ...from a field study conducted with 218 adults in agrarian communities in Peru's Andean highlands, we explored the extent to which education, non‐numeric fluid intelligence, crystallized intelligence, and numeracy skills were related to wealth. Wealth was measured using data on asset ownership (e.g., owning a fridge) and housing characteristics (e.g., toilet facilities). Structural equation modeling revealed that the level of schooling was associated with greater numeracy as well as greater non‐numeric fluid and crystallized intelligence; only greater numeracy was associated with greater wealth. Our findings are consistent with the idea that education is linked with financial outcomes, at least in part, through the enhancement of cognitive skills, particularly numeracy that then leads to greater wealth accumulation.
In this paper, we use choice architecture techniques to activate both social and personal norms, seeking to increase pro-environmental choices and to better understand the effect of such norm types ...on post-choice emotional responses. In four experiments, we make different social or personal norms salient by aligning choice environments with psychosocial mechanisms that activate different types of norms. We use different choice architecture techniques to change information, alter product sets, and generate the social consequences of choices. The target behavior, purchasing a recycled paper notebook, is captured through direct purchase behaviors or willingness to pay commitments. We find that choice architecture activates personal but not social norms, and that associated positive and negative emotions (guilt, shame, regret and pride) are elicited by choices but not by willingness to pay. Moreover, manipulating choice environment moderates the relationship between choice and norm-related emotions, such that positive emotional responses seem to be stronger than negative ones. The results suggest that choice architecture interventions can activate individual level beliefs about sustainability and help reduce the attitude-behavior gap.
Adult acquired flatfoot deformity (AAFD) is a common disorder that typically affects middle-aged and elderly women, resulting in foot pain, malalignment, and loss of function. The disorder is ...initiated most commonly by degeneration of the posterior tibialis tendon (PTT), which normally functions to maintain the talonavicular joint at the apex of the three arches of the foot. PTT degeneration encompasses tenosynovitis, tendinosis, tendon elongation, and tendon tearing. The malaligned foot is initially flexible but becomes rigid and constant as the disorder progresses. Tendon dysfunction commonly leads to secondary damage of the spring ligament and talocalcaneal ligaments and may be associated with injury to the deltoid ligament, plantar fascia, and other soft-tissue structures. Failure of multiple stabilizers appears to be necessary for development of the characteristic planovalgus deformity of AAFD, with a depressed plantar-flexed talus bone, hindfoot and/or midfoot valgus, and an everted flattened forefoot. AAFD also leads to gait dysfunction as the foot is unable to change shape and function adequately to accommodate the various phases of gait, which require multiple rapid transitions in foot position and tone for effective ambulation. The four-tier staging system for AAFD emphasizes physical examination findings and metrics of foot malalignment. Mild disease is managed conservatively, but surgical procedures directed at the soft tissues and/or bones become necessary and progressively more invasive as the disease progresses. Although much has been written about the imaging findings of AAFD, this article emphasizes the anatomy and function of the foot's stabilizing structures to help the radiologist better understand this disabling disorder.
RSNA, 2019.
Greed is best defined as the "experience of
desiring to acquire more and the dissatisfaction of never having enough"
(Seuntjens, Zeelenberg,
Breugelmans, & Van De Ven, 2015, p. 518). The ...Dispositional
Greed Scale (Seuntjens, Zeelenberg,
Van De Ven, & Breugelmans, 2015) is most often used to measure
greed and has been validated for various languages, although not for Spanish. We
present the first Spanish translation of the DGS. We tested two parallel
translations of the scale (N = 305) using two related but
distinct words for greedy: codicioso and
avaricioso. Both translations showed unidimensional factor
structure, with acceptable reliability. Multigroup confirmatory factor analysis
showed evidence for scalar equivalence of both translations. A comparison with
data from a previous English version of the scale showed evidence of metric
equivalence. Additionally, we found the expected relationships between greed and
envy, materialism, need for achievement, and self-improvement. We conclude the
DGS-Spanish has been successful in capturing the essential features of the
DGS.
Metabolite exchange within marine microbial communities transfers carbon and other major elements through global cycles and forms the basis of microbial interactions. Yet lack of gene annotations and ...concern about the quality of existing ones remain major impediments to revealing currencies of carbon flux. We employed an arrayed mutant library of the marine bacterium Ruegeria pomeroyi DSS-3 to experimentally annotate substrates of organic compound transporter systems, using mutant growth and compound drawdown analyses to link transporters to their cognate substrates. Mutant experiments verified substrates for thirteen R. pomeroyi transporters. Four were previously hypothesized based on gene expression data (taurine, glucose/xylose, isethionate, and cadaverine/putrescine/spermidine); five were previously hypothesized based on homology to experimentally annotated transporters in other bacteria (citrate, glycerol, N-acetylglucosamine, fumarate/malate/succinate, and dimethylsulfoniopropionate); and four had no previous annotations (thymidine, carnitine, cysteate, and 3-hydroxybutyrate). These bring the total number of experimentally-verified organic carbon influx transporters to 18 of 126 in the R. pomeroyi genome. In a longitudinal study of a coastal phytoplankton bloom, expression patterns of the experimentally annotated transporters linked them to different stages of the bloom, and also led to the hypothesis that citrate and 3-hydroxybutyrate were among the most highly available bacterial substrates. Improved functional annotation of the gatekeepers of organic carbon uptake is critical for deciphering carbon flux and fate in microbial ecosystems.
Recombinant adeno-associated virus (rAAV) is widely used in the neuroscience field to manipulate gene expression in the nervous system. However, a limitation to the use of rAAV vectors is the time ...and expense needed to produce them. To overcome this limitation, we evaluated whether unpurified rAAV vectors secreted into the media following scalable PEI transfection of HEK293T cells can be used in lieu of purified rAAV.
We packaged rAAV2-EGFP vectors in 30 different wild-type and mutant capsids and subsequently collected the media containing secreted rAAV. Genomic titers of each rAAV vector were assessed and the ability of each unpurified virus to transduce primary mixed neuroglial cultures (PNGCs), organotypic brain slice cultures (BSCs) and the mouse brain was evaluated.
There was ~ 40-fold wide variance in the average genomic titers of the rAAV2-EGFP vector packaged in the 30 different capsids, ranging from a low ~ 4.7 × 10
vector genomes (vg)/mL for rAAV2/5-EGFP to a high of ~ 2.0 × 10
vg/mL for a capsid mutant of rAAV2/8-EGFP. In PNGC studies, we observed a wide range of transduction efficiency among the 30 capsids evaluated, with the rAAV2/6-EGFP vector demonstrating the highest overall transduction efficiency. In BSC studies, we observed robust transduction by wild-type capsid vectors rAAV2/6, 2/8 and 2/9, and by capsid mutants of rAAV2/1, 2/6, and 2/8. In the in vivo somatic brain transgenesis (SBT) studies, we found that intra-cerebroventricular injection of media containing unpurified rAAV2-EGFP vectors packaged with select mutant capsids resulted in abundant EGFP positive neurons and astrocytes in the hippocampus and forebrain of non-transgenic mice. We demonstrate that unpurified rAAV can express transgenes at equivalent levels to lysate-purified rAAV both in vitro and in vivo. We also show that unpurified rAAV is sufficient to drive tau pathology in BSC and neuroinflammation in vivo, recapitulating previous studies using purified rAAV.
Unpurified rAAV vectors secreted into the media can efficiently transduce brain cells in vitro and in vivo, providing a cost-effective way to manipulate gene expression. The use of unpurified virus will greatly reduce costs of exploratory studies and further increase the utility of rAAV vectors for standard laboratory use.
This article re-examines the dissemination of the photographs and their subsequent reproduction of the now-canonical grain elevators and published in the early 20th century. For example, Walter ...Gropius used them as illustrations for his article in the 1913 Werkbund yearbook, while Le Corbusier included them in Vers une architecture. While the idea of a canon made up of buildings is widely accepted within architecture discourse, this article identifies and stresses the role of photographic canons as a means of further challenging these constructions. The article focuses on the moment when the reproductions of these photographs became canonical and on the mechanisms that such a construct implied. The photo reproductions were objects of trade and exchange, mobilised in relation to photographic media and different platforms for dissemination. On the one hand, this informed their reading as architectural and thus singular objects; on the other, the different materialisations of photo reproductions testify to their nature as commodities and objects of trade, and therefore to the consolidation of their canonical status.
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