7,439 research outputs found
X-ray CT analysis after blast of composite sandwich panels
Four composite sandwich panels with either single density or graded density foam cores and different face-sheet materials were subjected to full-scale underwater blast testing. The panels were subjected to 1kg PE4 charge at a stand-off distance of 1 m. The panel with graded density core and carbon fiber face-sheets had the lowest deflection. Post-blast damage assessment was carried out using X-ray CT scanning. The damage assessment revealed that there is a trade-off between reduced panel deflection and panel damage. This research has been performed as part of a program sponsored by the Office of Naval Research (ONR)
Pediatric sleep difficulties after moderateāsevere traumatic brain injury
The objective of this study is to systematically investigate sleep following moderateāsevere pediatric traumatic brain injury (TBI). School-aged children with moderateāsevere TBI identified via hospital records were invited to participate, along with a school-age sibling. Subjective reports and objective actigraphy correlates of sleep were recorded: Children's Sleep Habits Questionnaire (CSHQ), Sleep Self-Report questionnaire (SSR), and 5-night actigraphy. TBI participants (n = 15) and their siblings (n = 15) participated. Significantly more sleep problems were parent-reported (CSHQ: p = 0.003; d = 1.57), self-reported (SSR: p = 0.003; d = 1.40), and actigraph-recorded in the TBI group (sleep efficiency: p = 0.003; d = 1.23; sleep latency: p = 0.018; d = 0.94). There was no evidence of circadian rhythm disorders, and daytime napping was not prevalent. Moderateāsevere pediatric TBI was associated with sleep inefficiency in the form of sleep onset and maintenance problems. This preliminary study indicates that clinicians should be aware of sleep difficulties following pediatric TBI, and their potential associations with cognitive and behavioral problems in a group already at educational and psychosocial risk
Harmonizing Climate Change Mitigation and Adaptation in Transportation and Land-Use Planning in California Cities
Abstract: Recent extreme weather events in Californiaāwildfires, drought, and floodingāmake abundantly clear the need to plan effective responses to both the causes and the consequences of climate change. A central challenge for climate planning efforts has been identifying transportation and land-use (TLU) strategies that simultaneously reduce greenhouse gas emissions (āmitigationā) and adapt communities so that they will be less affected by the adverse impacts of climate change (āadaptationā). Sets of policies that collectively address both mitigation and adaptation are known as āintegrated actions.ā This study explores municipal climate planning in California to determine whether cities incorporate integrated actions into their plans, assess the potential drivers of conflict between mitigation and adaptation in municipal plans, and identify ways the State of California can help cities more effectively incorporate integrated actions.
The study methods consisted of a detailed analysis of climate planning documents from 23 California cities with particularly long histories of climate planning, plus interviews with 25 local, regional, and state officials who work on municipal climate planning.
The authors found that some cities did adopt packages of integrated actions, and, promisingly, two cities with recently updated climate plans explicitly focused on the need for integrated actions. However, most cities addressed climate mitigation and adaptation in separate efforts, potentially reducing synergies between the two types of action and even creating conflicts. Since the first generation of climate action plans focused primarily on mitigation of greenhouse gases (GHGs), adaptation strategies have not yet been effectively or fully combined into mitigation plans in many cities. Also, a cross-comparison of plan content and interview data suggests that cities often had sets of policies that could potentially create conflictsāmitigation policies that would undermine adaptation capacity, and vice versa. In addition, where a city did adopt integrated actions, these efforts are typically not labeled as such, nor do the policies appear within the same policy document.
The study findings suggest promising steps that both municipal and state governments can take to support integrated TLU actions at the local level. For example, cities can proactively link the content in climate mitigation and adaptation plansāa process that will require building the capacity for cross-collaboration between the various departments in charge of developing, implementing, and monitoring climate-related plans. As for the state government, it can provide funding specifically for planning and implementing integrated actions, offer technical support to help municipalities adopt programs and projects that produce integrated mitigation and adaptation benefits, and fund research in the area of integrated actions
Reproduction, growth and development in two contiguously allopatric rodent species, genus Scotinomys
http://deepblue.lib.umich.edu/bitstream/2027.42/56395/1/MP151.pd
Identifying experiences of supportive care of children and young people affected by kidney failure: a qualitative systematic review.
Children and young people affected by kidney failure experience complexities in their care. Little is known about the unique needs of this young patient population group living with a long-term condition. A meta-aggregation of all qualitative studies was conducted to identify experiences of supportive care among children and young people living with kidney failure. A systematic review of qualitative studies was conducted following the Joanna Briggs Institute meta-aggregation method. This review has been reported according to the PRISMA statement guidelines. Six electronic databases (CINAHL, Cochrane Library, MEDLINE, Proquest, PsycINFO, and Scopus) were comprehensively searched by an expert systematic review librarian using keywords and subject headings, from inception to September 2022. All studies were accessed using a predetermined inclusion and exclusion criteria. Methodological quality assessment and data extraction performed. Qualitative findings accompanied by illustrative quotes from included studies were extracted and grouped into categories which created the overall synthesised findings. A total of 34 studies were included in this review representing a total of 613 children and young people affected by kidney failure. There was a total of 190 findings which created 13 categories representing experiences of supportive care. The meta-aggregation developed five synthesised findings namely: 'physical needs', 'information and technology', 'treatment and healthcare', 'social needs' and 'psychological impacts'. This systematic review identified that children and young people affected by kidney failure can experience a range of unmet supportive care needs in routine clinical services. Kidney failure impacted children and young people's self-identify, social and peer networks, introduced daily practical needs because of inherent physical and psychological burden due to the failure and associated treatments. Despite improvements in the medical management of kidney failure in children and young people, further attention is needed to optimise supported self-management in this young patient group
Plasma Physics
Contains reports on three research projects.U. S. Atomic Energy Commission (Contract AT(30- 1)- 1842
MeV dark matter and small scale structure
Weakly interacting massive particles with electroweak scale masses (neutralinos, etc.) remain in kinetic equilibrium with other particle species until temperatures approximately in the range of 10 MeV to 1 GeV, leading to the formation of dark matter substructure with masses as small as 10^(ā4) M_ā to 10^(ā12) M_ā. However, if dark matter consists of particles with MeV scale masses, as motivated by the observation of 511 keV emission from the galactic bulge, such particles are naturally expected to remain in kinetic equilibrium with the cosmic neutrino background until considerably later times. This would lead to a strong suppression of small scale structure with masses below about 10^7 M_ā to 10^4 M_ā. This cutoff scale has important implications for present and future searches for faint local group satellite galaxies and for the missing satellites problem. We also summarize current constraints on the MeV dark matter scenario
The Effects of Varying Doses of Caffeine on Sports Skill Related Performance and Reaction Time
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Two photon annihilation of Kaluza-Klein dark matter
We investigate the fermionic one-loop cross section for the two photon
annihilation of Kaluza-Klein (KK) dark matter particles in a model of universal
extra dimensions (UED). This process gives a nearly mono-energetic gamma-ray
line with energy equal to the KK dark matter particle mass. We find that the
cross section is large enough that if a continuum signature is detected, the
energy distribution of gamma-rays should end at the particle mass with a peak
that is visible for an energy resolution of the detector at the percent level.
This would give an unmistakable signature of a dark matter origin of the
gamma-rays, and a unique determination of the dark matter particle mass, which
in the case studied should be around 800 GeV. Unlike the situation for
supersymmetric models where the two-gamma peak may or may not be visible
depending on parameters, this feature seems to be quite robust in UED models,
and should be similar in other models where annihilation into fermions is not
helicity suppressed. The observability of the signal still depends on largely
unknown astrophysical parameters related to the structure of the dark matter
halo. If the dark matter near the galactic center is adiabatically contracted
by the central star cluster, or if the dark matter halo has substructure
surviving tidal effects, prospects for detection look promising.Comment: 17 pages, 3 figures; slightly revised versio
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