163 research outputs found
An Acute Bout of Exercise Improves the Cognitive Performance of Older Adults.
There is evidence that an acute bout of exercise confers cognitive benefits, but it is largely 2 unknown what the optimal mode and duration of exercise is and how cognitive performance 3 changes over time after exercise. We compared the cognitive performance of 31 older adults 4 using the Stroop test before, immediately after, and at 30 and 60 minutes after a 10 and 30 5 minute aerobic or resistance exercise session. Heart rate and feelings of arousal were also 6 measured before, during and after exercise. We found that independent of mode or duration of 7 exercise, the participants improved in the Stroop Inhibition task immediately post-exercise. We 8 did not find the exercise influenced the performance of the Stroop Color or Stroop Word 9 Interference tasks. Our findings suggest that an acute bout of exercise can improve cognitive 10 performance, and in particular the more complex executive functioning, of older adults
On the Deformation of a Hyperelastic Tube Due to Steady Viscous Flow Within
In this chapter, we analyze the steady-state microscale fluid--structure
interaction (FSI) between a generalized Newtonian fluid and a hyperelastic
tube. Physiological flows, especially in hemodynamics, serve as primary
examples of such FSI phenomena. The small scale of the physical system renders
the flow field, under the power-law rheological model, amenable to a
closed-form solution using the lubrication approximation. On the other hand,
negligible shear stresses on the walls of a long vessel allow the structure to
be treated as a pressure vessel. The constitutive equation for the microtube is
prescribed via the strain energy functional for an incompressible, isotropic
Mooney--Rivlin material. We employ both the thin- and thick-walled formulations
of the pressure vessel theory, and derive the static relation between the
pressure load and the deformation of the structure. We harness the latter to
determine the flow rate--pressure drop relationship for non-Newtonian flow in
thin- and thick-walled soft hyperelastic microtubes. Through illustrative
examples, we discuss how a hyperelastic tube supports the same pressure load as
a linearly elastic tube with smaller deformation, thus requiring a higher
pressure drop across itself to maintain a fixed flow rate.Comment: 19 pages, 3 figures, Springer book class; v2: minor revisions, final
form of invited contribution to the Springer volume entitled "Dynamical
Processes in Generalized Continua and Structures" (in honour of Academician
D.I. Indeitsev), eds. H. Altenbach, A. Belyaev, V. A. Eremeyev, A. Krivtsov
and A. V. Porubo
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a 4.4σ signal of ν̄e appearance in a 2 GeV ν̄μ beam at a distance of 810 km. Using 12.33×1020 protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν̄μ→ν̄e candidates with a background of 10.3 and 102 ν̄μ→ν̄μ candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm322|=2.48-0.06+0.11×10-3 eV2/c4 and sin2θ23 in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δCP=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ23 values in the upper octant by 1.6σ
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a
4.4
σ
signal of
¯
ν
e
appearance in a 2 GeV
¯
ν
μ
beam at a distance of 810 km. Using
12.33
×
10
20
protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27
¯
ν
μ
→
¯
ν
e
candidates with a background of 10.3 and 102
¯
ν
μ
→
¯
ν
μ
candidates. This new antineutrino data are combined with neutrino data to measure the parameters
|
Δ
m
2
32
|
=
2.4
8
+
0.11
−
0.06
×
10
−
3
eV
2
/
c
4
and
sin
2
θ
23
in the ranges from (0.53–0.60) and (0.45–0.48) in the normal neutrino mass hierarchy. The data exclude most values near
δ
C
P
=
π
/
2
for the inverted mass hierarchy by more than
3
σ
and favor the normal neutrino mass hierarchy by
1.9
σ
and
θ
23
values in the upper octant by
1.6
σ
Measurement of neutrino-induced neutral-current coherent π0 production in the NOvA near detector
The cross section of neutrino-induced neutral-current coherent π0 production on a carbon-dominated target is measured in the NOvA near detector. This measurement uses a narrow-band neutrino beam with an average neutrino energy of 2.7 GeV, which is of interest to ongoing and future long-baseline neutrino oscillation experiments. The measured, flux-averaged cross section is σ=13.8±0.9(stat)±2.3(syst)×10−40cm2/nucleus, consistent with model prediction. This result is the most precise measurement of neutral-current coherent π0 production in the few-GeV neutrino energy region
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