2,141 research outputs found
The Future of Perianesthesia Nursing: Shared Governance Empowers Nurses to Focus on Professional Development
Validation and noise robustness assessment of microscopic anisotropy estimation with clinically feasible double diffusion encoding MRI
Purpose: Double diffusion encoding (DDE) MRI enables the estimation of microscopic diffusion anisotropy, yielding valuable information on tissue microstructure. A recent study proposed that the acquisition of rotationally invariant DDE metrics, typically obtained using a spherical ā5ādesign,ā could be greatly simplified by assuming Gaussian diffusion, facilitating reduced acquisition times that are more compatible with clinical settings. Here, we aim to validate the new minimal acquisition scheme against the standard DDE 5ādesign, and to quantify the proposed method's noise robustness to facilitate future clinical use. /
Theory and Methods: DDE MRI experiments were performed on both ex vivo and in vivo rat brains at 9.4 T using the 5ādesign and the proposed minimal design and taking into account the difference in the number of acquisitions. The ensuing microscopic fractional anisotropy (Ī¼FA) maps were compared over a range of bāvalues up to 5000 s/mm2. Noise robustness was studied using analytical calculations and numerical simulations. /
Results: The minimal protocol quantified Ī¼FA at an accuracy comparable to the estimates obtained by means of the more theoretically robust DDE 5ādesign. Ī¼FA's sensitivity to noise was found to strongly depend on compartment anisotropy and tensor magnitude in a nonlinear manner. When Ī¼FA < 0.75 or when mean diffusivity is particularly low, very high signalātoānoise ratio is required for precise quantification of ĀµFA. /
Conclusion: Our work supports using DDE for quantifying microscopic diffusion anisotropy in clinical settings but raises hitherto overlooked precision issues when measuring Ī¼FA with DDE and typical clinical signalātoānoise ratio
Huddle and Safety
The purposed evidence-based practice (EBP) project focuses on a nursing intervention (team huddles) to increase safety and reduce inpatient fall rates. Negative outcomes to consider from an inpatient fall are harm and injury to the patient along with increased health care cost for the patient as well as hospital facility. Accrued cost associated with an in-patient injury resulting from a fall is not reimbursed according to the Centers for Medicare and Medicaid Services. The additional cost for hospital-acquired falls is estimated to be 1,277 to $14,665) (Agency for Healthcare Research and Quality, 2017). This was only related to acute care costs such as increased length of stay and diagnostic tests that will not be reimbursed by most insurers including federal programs. The accrued cost could be greater when other outlays such as rehabilitation care or lawsuits are included. Expenses have outpaced revenue for acute-care hospitals in every year but one since 2003; without an intervention to reduce expenses (specifically cost accrued with in-patient falls) the hospital is left financially vulnerable. The EBP project: to implement a team huddle at the beginning of each shift on the Medical-Surgical floors 1&2 at UTHealth Athens Hospital. The total time purposed for the project is 12-weeks. There will be 3 phases including an evaluation period. A team huddle is a cost-effective intervention with potential to impact overall department safety, improve patient and employee satisfaction, as well as offering financial benefit
Sea anemones may thrive in a high CO2 world
Increased seawater pCO 2, and in turn 'ocean acidification' (OA), is predicted to profoundly impact marine ecosystem diversity and function this century. Much research has already focussed on calcifying reef-forming corals (Class: Anthozoa) that appear particularly susceptible to OA via reduced net calcification. However, here we show that OA-like conditions can simultaneously enhance the ecological success of non-calcifying anthozoans, which not only play key ecological and biogeochemical roles in present day benthic ecosystems but also represent a model organism should calcifying anthozoans exist as less calcified (soft-bodied) forms in future oceans. Increased growth (abundance and size) of the sea anemone (Anemonia viridis) population was observed along a natural CO 2 gradient at Vulcano, Italy. Both gross photosynthesis (P G) and respiration (R) increased with pCO 2 indicating that the increased growth was, at least in part, fuelled by bottom up (CO 2 stimulation) of metabolism. The increase of P G outweighed that of R and the genetic identity of the symbiotic microalgae (Symbiodinium spp.) remained unchanged (type A19) suggesting proximity to the vent site relieved CO 2 limitation of the anemones' symbiotic microalgal population. Our observations of enhanced productivity with pCO 2, which are consistent with previous reports for some calcifying corals, convey an increase in fitness that may enable non-calcifying anthozoans to thrive in future environments, i.e. higher seawater pCO 2. Understanding how CO 2-enhanced productivity of non- (and less-) calcifying anthozoans applies more widely to tropical ecosystems is a priority where such organisms can dominate benthic ecosystems, in particular following localized anthropogenic stress. Ā© 2012 Blackwell Publishing Ltd
Constrained analytical interrelations in neutrino mixing
Hermitian squared mass matrices of charged leptons and light neutrinos in the
flavor basis are studied under general additive lowest order perturbations away
from the tribimaximal (TBM) limit in which a weak basis with mass diagonal
charged leptons is chosen. Simple analytical expressions are found for the
three measurable TBM-deviants in terms of perturbation parameters appearing in
the neutrino and charged lepton eigenstates in the flavor basis. Taking
unnatural cancellations to be absent and charged lepton perturbation parameters
to be small, interrelations are derived among masses, mixing angles and the
amount of CP-violation.Comment: To be published in the Springer Proceedings in the Physics Series
under the heading of the XXI DAE-BRNS Symposium (Guwahati, India
Absolutely stable proton and lowering the gauge unification scale
A unified model is constructed, based on flipped SU(5) in which the proton is absolutely stable. The model requires the existence of new leptons with masses of order the weak scale. The possibility that the unification scale could be extremely low is discussed
A Collective Breaking of R-Parity
Supersymmetric theories with an R-parity generally yield a striking missing
energy signature, with cascade decays concluding in a neutralino that escapes
the detector. In theories where R-parity is broken the missing energy is
replaced with additional jets or leptons, often making traditional search
strategies ineffective. Such R-parity violation is very constrained, however,
by resulting B and L violating signals, requiring couplings so small that LSPs
will decay outside the detector in all but a few scenarios. In theories with
additional matter fields, R-parity can be broken collectively, such that
R-parity is not broken by any single coupling, but only by an ensemble of
couplings. Cascade decays can proceed normally, with each step only sensitive
to one or two couplings at a time, but B and L violation requires the full set,
yielding a highly suppressed constraint. s-channel production of new scalar
states, typically small for standard RPV, can be large when RPV is broken
collectively. While missing energy is absent, making these models difficult to
discover by traditional SUSY searches, they produce complicated many object
resonances (MORes), with many different possible numbers of jets and leptons.
We outline a simple model and discuss its discoverability at the LHC.Comment: 28 pages, 10 figure
Learning While Black: A Qualitative Analysis of the Impact of Race in a U.S. High School
One of the major contributing factors to the Black-White achievement gap is school context. While many factors can affect academic achievement amongst Black youth, school climate and inter-racial relations are among the root causes which impact Black studentsā development. In this qualitative study, we conducted secondary analysis of existing data consisting of interview transcripts and focus group discussions held in 2013 with 21 Black students who attended a public charter high school in Michigan. Open access data were downloaded from the University of Michigan Inter-University Consortium for Political and Social Research (ICPSR) database. We analyzed qualitative data for themes and constructs related to school context and such influences on Black youth development. The following three constructs were identified: racial identity of Black youth, the impact of teachers on Black studentsā racial identity and development, and lastly, exploring the dominant culture of the U.S. education system. For researchers, this data highlights a need for more studies on the intersection of race, school environment, and youth development. For administrators and policy makers, the results emphasize the need for investment and engagement in the daily experiences of Black students, reducing racism, and increasing diversity of curriculum. Teachers and school administrators may benefit from specialized training to better address cultural, educational, and developmental needs of Black youth in the context of their role in school
The Maximal Inverse Seesaw from Operator and Oscillating Asymmetric Sneutrino Dark Matter
The maximal supersymmetric inverse seesaw mechanism (MSIS)
provides a natural way to relate asymmetric dark matter (ADM) with neutrino
physics. In this paper we point out that, MSIS is a natural outcome if one
dynamically realizes the inverse seesaw mechanism in the next-to minimal
supersymmetric standard model (NMSSM) via the dimension-five operator
, with the NMSSM singlet developing TeV scale VEV; it
slightly violates lepton number due to the suppression by the fundamental scale
, thus preserving maximally. The resulting sneutrino is a
distinguishable ADM candidate, oscillating and favored to have weak scale mass.
A fairly large annihilating cross section of such a heavy ADM is available due
to the presence of singlet.Comment: journal versio
Minimal flavour violation extensions of the seesaw
We analyze the most natural formulations of the minimal lepton flavour
violation hypothesis compatible with a type-I seesaw structure with three heavy
singlet neutrinos N, and satisfying the requirement of being predictive, in the
sense that all LFV effects can be expressed in terms of low energy observables.
We find a new interesting realization based on the flavour group (being and respectively the SU(2) singlet and
doublet leptons). An intriguing feature of this realization is that, in the
normal hierarchy scenario for neutrino masses, it allows for sizeable
enhancements of transitions with respect to LFV processes involving
the lepton. We also discuss how the symmetries of the type-I seesaw
allow for a strong suppression of the N mass scale with respect to the scale of
lepton number breaking, without implying a similar suppression for possible
mechanisms of N productionComment: 14 pages, 6 figure
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