297 research outputs found
Orchard Bin ATV Trailer
A local orchardist was experiencing a problem that was being caused by their lack of apple picking bin moving equipment. The orchardist needed a well-engineered solution to this lack of equipment. The solution arrived at was a five bin trailer. There were multiple design requirements for this trailer, including the device needing to be able to interface with an ATV, be able to be loaded by hand, be able to carry five bins, and not exceed a budget of $750. While perfecting the design of the trailer, a number of different disciplines were utilized, which included dynamics, kinematics, static loading analysis, and material strength analysis. Different technologies were used to create a final design, including CAD modeling using Solidworks modeling software, MDSolids for maximum material stress predictions, and spreadsheet optimization of material cross sections using Microsoft Excel. The manufacture and assembly of the trailer device made use of different fabrication techniques, including welded and bolted joints. The results of the performance of this trailer were measured with multiple instruments, including a spring scale for measuring how the weight of the trailer hitch deviated from the calculated value. Also measured experimentally was the trailers ability to resist deformation occurring from a full load being dropped six inches onto the trailer rails
Prospective memory functioning among ecstasy/polydrug users: evidence from the Cambridge Prospective Memory Test (CAMPROMPT)
Rationale:
Prospective memory (PM) deficits in recreational drug users have been documented in recent years. However, the assessment of PM has largely been restricted to self-reported measures that fail to capture the distinction between event-based and time-based PM. The aim of the present study is to address this limitation.
Objectives:
Extending our previous research, we augmented the range laboratory measures of PM by employing the CAMPROMPT test battery to investigate the impact of illicit drug use on prospective remembering in a sample of cannabis only, ecstasy/polydrug and non-users of illicit drugs, separating event and time-based PM performance. We also administered measures of executive function and retrospective memory in order to establish whether ecstasy/polydrug deficits in PM were mediated by group differences in these processes.
Results:
Ecstasy/polydrug users performed significantly worse on both event and time-based prospective memory tasks in comparison to both cannabis only and non-user groups. Furthermore, it was found that across the whole sample, better retrospective memory and executive functioning was associated with superior PM performance. Nevertheless, this association did not mediate the drug-related effects that were observed. Consistent with our previous study, recreational use of cocaine was linked to PM deficits.
Conclusions:
PM deficits have again been found among ecstasy/polydrug users, which appear to be unrelated to group differences in executive function and retrospective memory. However, the possibility that these are attributable to cocaine use cannot be excluded
The high-speed X-ray camera on AXIS
AXIS is a Probe-class mission concept that will provide high-throughput,
high-spatial-resolution X-ray spectral imaging, enabling transformative studies
of high-energy astrophysical phenomena. To take advantage of the advanced
optics and avoid photon pile-up, the AXIS focal plane requires detectors with
readout rates at least 20 times faster than previous soft X-ray imaging
spectrometers flying aboard missions such as Chandra and Suzaku, while
retaining the low noise, excellent spectral performance, and low power
requirements of those instruments. We present the design of the AXIS high-speed
X-ray camera, which baselines large-format MIT Lincoln Laboratory CCDs
employing low-noise pJFET output amplifiers and a single-layer polysilicon gate
structure that allows fast, low-power clocking. These detectors are combined
with an integrated high-speed, low-noise ASIC readout chip from Stanford
University that provides better performance than conventional discrete
solutions at a fraction of their power consumption and footprint. Our
complementary front-end electronics concept employs state of the art digital
video waveform capture and advanced signal processing to deliver low noise at
high speed. We review the current performance of this technology, highlighting
recent improvements on prototype devices that achieve excellent noise
characteristics at the required readout rate. We present measurements of the
CCD spectral response across the AXIS energy band, augmenting lab measurements
with detector simulations that help us understand sources of charge loss and
evaluate the quality of the CCD backside passivation technique. We show that
our technology is on a path that will meet our requirements and enable AXIS to
achieve world-class science.Comment: 17 pages, 11 figures, submitted to Proceedings of SPIE Optics +
Photonics 202
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Establishment of a Statewide Network for Carbapenem-Resistant Enterobacteriaceae Prevention in a Low-Incidence Region
OBJECTIVE: To establish a statewide network to detect, control, and prevent the spread of carbapenem-resistant Enterobacteriaceae (CRE)
in a region with a low incidence of CRE infection.
DESIGN: Implementation of the Drug Resistant Organism Prevention and Coordinated Regional Epidemiology (DROP-CRE) Network.
SETTING AND PARTICIPANTS: Oregon infection prevention and microbiology laboratory personnel, including 48 microbiology laboratories,
62 acute care facilities, and 140 long-term care facilities.
METHODS: The DROP-CRE working group, comprising representatives from academic institutions and public health, convened an
interdisciplinary advisory committee to assist with planning and implementation of CRE epidemiology and control efforts. The working
group established a statewide CRE definition and surveillance plan; increased the state laboratory capacity to perform the modified Hodge
test and polymerase chain reaction for carbapenemases in real time; and administered surveys that assessed the needs and capabilities of
Oregon infection prevention and laboratory personnel. Results of these inquiries informed CRE education and the response plan.
RESULTS: Of 60 CRE reported from November 2010 through April 2013, only 3 were identified as carbapenemase producers; the cases
were not linked, and no secondary transmission was found. Microbiology laboratories, acute care facilities, and long-term care facilities
reported lacking carbapenemase testing capability, reliable interfacility communication, and CRE awareness, respectively. Survey findings
informed the creation of the Oregon CRE Toolkit, a state-specific CRE guide booklet.
CONCLUSIONS: A regional epidemiology surveillance and response network has been implemented in Oregon in advance of widespread
CRE transmission. Prospective surveillance will determine whether this collaborative approach will be successful at forestalling the emergence
of this important healthcare-associated pathogen.This is the publisher’s final pdf. The published article is copyrighted by the University of Chicago Press on behalf of the Society for Healthcare Epidemiology of America and can be found at: http://www.press.uchicago.edu/ucp/journals/journal/iche.html
Hormonal signaling in cnidarians : do we understand the pathways well enough to know whether they are being disrupted?
Author Posting. © The Author, 2006. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Ecotoxicology 16 (2007): 5-13, doi:10.1007/s10646-006-0121-1.Cnidarians occupy a key evolutionary position as basal metazoans and are ecologically
important as predators, prey and structure-builders. Bioregulatory molecules (e.g.,
amines, peptides and steroids) have been identified in cnidarians, but cnidarian signaling
pathways remain poorly characterized. Cnidarians, especially hydras, are regularly used
in toxicity testing, but few studies have used cnidarians in explicit testing for signal
disruption. Sublethal endpoints developed in cnidarians include budding, regeneration,
gametogenesis, mucus production and larval metamorphosis. Cnidarian genomic
databases, microarrays and other molecular tools are increasingly facilitating mechanistic
investigation of signaling pathways and signal disruption. Elucidation of cnidarian
signaling processes in a comparative context can provide insight into the evolution and
diversification of metazoan bioregulation. Characterizing signaling and signal disruption
in cnidarians may also provide unique opportunities for evaluating risk to valuable
marine resources, such as coral reefs
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Effects of episodic future thinking and self-projection on children’s prospective memory performance
The present study is the first to investigate the benefits of episodic future thinking (EFT) at encoding on prospective memory (PM) in preschool (age: M = 66.34 months, SD = 3.28)and primary school children (age: M = 88.36 months, SD = 3.12). A second aim was to examine if self-projection influences the possible effects of EFT instructions. PM was assessed using a standard PM paradigm in children with a picture-naming task as the ongoing activity in which the PM task was embedded. Further, two first- and two second-order ToM tasks were administered as indicator of children’s self-projection abilities. Forty-one preschoolers and 39 school-aged children were recruited. Half of the participants in each age group were instructed to use EFT as a strategy to encode the PM task, while the others received standard PM instructions. Results revealed a significant age effect, with school-aged children significantly outperforming preschoolers and a significant effect of encoding condition with overall better performance when receiving EFT instructions compared to the standard encoding condition. Even though the interaction between age group and encoding condition was not significant, planned comparisons revealed first evidence that compared to the younger age group, older children’s PM benefited more from EFT instructions during intention encoding. Moreover, results showed that although self-projection had a significant impact on PM performance, it did not influence the effects of EFT instructions. Overall, results indicate that children can use EFT encoding strategies to improve their PM performance once EFT abilities are sufficiently developed. Further, they provide first evidence that in addition to executive functions, which have already been shown to influence the development of PM across childhood, self-projection seems to be another key mechanism underlying this development
Modulation of COUP-TF Expression in a Cnidarian by Ectopic Wnt Signalling and Allorecognition
COUP transcription factors are required for the regulation of gene expression underlying development, differentiation, and homeostasis. They have an evolutionarily conserved function, being a known marker for neurogenesis from cnidarians to vertebrates. A homologue of this gene was shown previously to be a neuronal and nematocyte differentiation marker in Hydra. However, COUP-TFs had not previously been studied in a colonial cnidarian.We cloned a COUP-TF homologue from the colonial marine cnidarian Hydractinia echinata. Expression of the gene was analysed during normal development, allorecognition events and ectopic Wnt activation, using in situ hybridisation and quantitative PCR. During normal Hydractinia development, the gene was first expressed in post-gastrula stages. It was undetectable in larvae, and its mRNA was present again in putative differentiating neurons and nematocytes in post-metamorphic stages. Global activation of canonical Wnt signalling in adult animals resulted in the upregulation of COUP-TF. We also monitored a strong COUP-TF upregulation in stolons undergoing allogeneic interactions. COUP-TF mRNA was most concentrated in the tissues that contacted allogeneic, non-self tissues, and decreased in a gradient away from the contact area. Interestingly, the gene was transiently upregulated during initial contact of self stolons, but dissipated rapidly following self recognition, while in non-self contacts high expression levels were maintained.We conclude that COUP-TF is likely involved in neuronal/nematocyte differentiation in a variety of contexts. This has now been shown to include allorecognition, where COUP-TF is thought to have been co-opted to mediate allorejection by recruiting stinging cells that are the effectors of cytotoxic rejection of allogeneic tissue. Our findings that Wnt activation upregulates COUP-TF expression suggests that Wnts' role in neuronal differentiation could be mediated through COUP-TF
Scaling the state: Egypt in the third millennium BC
Discussions of the early Egyptian state suffer from a weak consideration of scale. Egyptian archaeologists derive their arguments primarily from evidence of court cemeteries, elite tombs, and monuments of royal display. The material informs the analysis of kingship, early writing, and administration but it remains obscure how the core of the early Pharaonic state was embedded in the territory it claimed to administer. This paper suggests that the relationship between centre and hinterland is key for scaling the Egyptian state of the Old Kingdom (ca. 2,700-2,200 BC). Initially, central administration imagines Egypt using models at variance with provincial practice. The end of the Old Kingdom demarcates not the collapse, but the beginning of a large-scale state characterized by the coalescence of central and local models
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