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61.
62.
Jason D. Runyan Timothy A. Steenbergh Charles Bainbridge Douglas A. Daugherty Lorne Oke Brian N. Fry 《PloS one》2013,8(8)
We have designed a flexible ecological momentary assessment/intervention smartphone (EMA/EMI) “app”. We examine the utility of this app for collecting real-time data, and assessing intra-subject variability, by using it to assess how freshman undergraduates spend their time. We also explore whether its use can promote greater self-awareness. Participants were randomly divided into an experimental group, who used the app, and a control group, who did not. We used the app to collect both randomized in-the-moment data as well as end-of-day data to assess time use. Using a posttest survey we asked participants questions about how they spent time throughout the school semester. We also asked the experimental group about their experience with the app. Among other findings, 80.49% participants indicated that they became more aware of how they spent their time using the app. Corroborating this report, among the experimental group, end-of-semester self-assessment of time spent wasted, and time spent using electronics recreationally, predicted semester GPA at a strength comparable to high school GPA and ACT score (two of the best single predictors for first semester college GPA), but had no correlation among controls. We discuss the advantages and limitations of using apps, such as ours, for EMA and/or EMI. 相似文献
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Ishchenko AA Vasilenko NL Sinitsina OI Yamkovoy VI Fedorova OS Douglas KT Nevinsky GA 《Biochemistry》2002,41(24):7540-7548
X-ray analysis does not provide quantitative estimates of the relative importance of the molecular contacts it reveals or of the relative contributions of specific and nonspecific interactions to the total affinity of specific DNA to enzymes. Stepwise increase of DNA ligand complexity has been used to estimate the relative contributions of virtually every nucleotide unit of 8-oxoguanine-containing DNA to its total affinity for Escherichia coli 8-oxoguanine DNA glycosylase (Fpg protein). Fpg protein can interact with up to 13 nucleotide units or base pairs of single- and double-stranded ribo- and deoxyribo-oligonucleotides of different lengths and sequences through weak additive contacts with their internucleotide phosphate groups. Bindings of both single-stranded and double-stranded oligonucleotides follow similar algorithms, with additive contributions to the free energy of binding of the structural components (phosphate, sugar, and base). Thermodynamic models are provided for both specific and nonspecific DNA sequences with Fpg protein. Fpg protein interacts nonspecifically with virtually all of the base-pair units within its DNA-binding cleft: this provides approximately 7 orders of magnitude of affinity (Delta G degrees approximately equal to -9.8 kcal/mol) for DNA. In contrast, the relative contribution of the 8-oxoguanine unit of the substrate (Delta G degrees approximately equal to -0.90 kcal/mol) together with other specific interactions is <2 orders of magnitude (Delta G degrees approximately equal to -2.8 kcal/mol). Michaelis complex formation of Fpg protein with DNA containing 8-oxoguanine cannot of itself provide the major part of the enzyme specificity, which lies in the k(cat) term; the rate is increased by 6-8 orders of magnitude on going from nonspecific to specific oligodeoxynucleotides. 相似文献
66.
Rob J. Hunt Andrew W. Claridge Peter J. S. Fleming Ross B. Cunningham Benjamin G. Russell Douglas J. Mills 《Ecological Management & Restoration》2014,15(3):231-238
The feral Goat (Capra hircus) has successfully exploited a range of landscapes around the world with occurrences of overabundance resulting in significant damage to ecological values. In forested ecosystems in Australia, there are currently limited means to control the species when compared to the range of management techniques available for other pest animals. To redress this deficiency, we designed a feed structure combined with commercially available salt blocks to attract goats to set locations in a forested study area. Structures that exploited differences in the pedal morphology (foot size and shape) of native herbivores (kangaroos and wallabies) and ungulates (feral goats and deer) were found to be highly target‐specific, with feral goats freely able to access salt blocks, whilst nontarget native species were effectively excluded. Other introduced ungulate species, Fallow Deer (Dama dama) and Red Deer (Cervus elaphus), successfully accessed salt blocks in feed structures but at a considerably lower rate than feral goats. The capacity to present a range of bait types within a target‐specific feed structure, once matched with a humane toxicant, could provide land managers with an additional cost‐effective lethal control tool for future management of feral ungulates, particularly goats. 相似文献
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Both the Mississippi and Missouri rivers experienced major flooding in the spring and summer of 1993, inundating much of their
floodplains for long periods, and allowing fish access to vast but previously inaccessible benthic foraging areas. In response
to the latter, we hypothesized that flathead catfish (Pylodictis olivaris) would exhibit altered post-flooding growth as compared to like-aged fish whose lives were flood-free. To test this hypothesis,
we obtained the left pectoral fin spines from hoop-netted Mississippi River flathead catfish collected in the vicinity of
Crystal City, Missouri, USA, and conducted an individual-based back-calculated growth comparison of individuals captured pre-flood
(1991) and post-flood (1996). For like-aged cohorts, our back-calculated length-at-age data clearly show that the post-flooding
growth in 1996-collected fish was superior to that of the 1991-collected fish that had experienced less exceptional flow regimes.
This outcome suggests that increased forage or/and foraging opportunities can be a consequence of flooding, and that flathead
catfish are able to capitalize on this. The natural flooding regime of big rivers may thus be an important contributor to
the growth and success of certain fish species; consequently, modifying the river’s natural hydrograph and channel morphology
may be detrimental.
Handling editor: J. A. Cambray
An erratum to this article is available at . 相似文献
69.
Charles Douglas 《Journal of bioethical inquiry》2009,6(3):337-347
In contemplating any life and death moral dilemma, one is often struck by the possible importance of two distinctions; the
distinction between killing and “letting die”, and the distinction between an intentional killing and an action aimed at some
other outcome that causes death as a foreseen but unintended “side-effect”. Many feel intuitively that these distinctions
are morally significant, but attempts to explain why this might be so have been unconvincing. In this paper, I explore the
problem from an explicitly consequentialist point of view. I first review and endorse the arguments that the distinctions
cannot be drawn with perfect clarity, and that they do not have the kind of fundamental significance required to defend an
absolute prohibition on killing. I go on to argue that the distinctions are nonetheless important. A complete consequentialist
account of morality must include a consideration of our need and ability to construct and follow rules; our instincts about
these rules; and the consequences (to the agent and to others) that might follow if the agent breaks a good general rule,
particularly if this involves acting contrary to moral instinct. With this perspective, I suggest that the distinctions between
killing and letting die and between intending and foreseeing do have moral relevance, especially for those involved in the
care of the sick and dying. 相似文献
70.
Edmonson AM Mayfield DK Vervoort V DuPont BR Argyropoulos G 《Cell communication & adhesion》2002,9(1):15-27
Functional mitochondria require up to 1000 proteins to function properly, with 99% synthesized as precursors in the cytoplasm and transported into the mitochondria with the aid of cytosolic chaperones and mitochondrial translocators (import components). Proteins to be imported are chaperoned to the mitochondria by the cytosolic heat shock protein (cHSP70) and are immediately pursued by Translocators of the Outer Membrane (TOMs), followed by transient interactions of the unfolded proteins with Translocators of the Inner Membrane (TIMs). In the present study, we describe a human gene, TOMM70A, orthologous to the yeast Tom70 import component. TOMM70A is ubiquitously expressed in human tissues, maps on chromosome 3q13.1-q13.2 and consists of 12 coding exons spanning over 37 kb. TOMM70A localizes in the mitochondria of COS-7 cells, and in organello import assays confirmed its presence in the Outer Mitochondrial membrane (OM) of rat liver mitochondria. TOMM70A could play a significant role in the import of nuclear-encoded mitochondrial proteins with internal targeting sites such as ADP/ATP carriers and the uncoupling proteins. 相似文献