To assess the changes in patient strength and function from 4- to 6-month assessments following ACLR, determine relationships between changes in strength to changes in subjective function, and ...identify factors that predict patients that fail to increase in strength.
Prospective, Cohort Study.
Controlled Laboratory.
Forty-seven patients(27 female, 24.3 ± 11.1 years) completed a battery of performance assessments at approximately 4- and 6-months following primary ACLR (4.03 ±0 .49 and 6.46 ±0 .68 months).
Subjective scores and isokinetic knee flexor and extensor strength were compared across visits. Patients were categorized per their ability to increase in strength beyond a previously defined threshold(0.22 Nm/kg). Binary logistic regression models were used to determine predictors of patients that failed to meet strength changes.
Patients demonstrated improvements in patient-reported outcomes and strength measures between visits(P’s < 0.05). Higher age (B = −0.073, P = .039), lower pre-injury activity levels (B = 0.61, P = .022), and higher limb symmetry indexes (B = −0.044, P = .05) at 4-months were predictors of patients that did not achieve improvements in quadriceps strength between assessments.
From 4- to 6-months post-ACLR, increases in subjective function, strength and symmetry were observed. High quadriceps symmetry at interim assessments without consideration of the magnitude of strength values could overestimate recovery of quadriceps function.
•Higher age, lower activity, and higher LSI were predictors of low strength gains.•Interim assessments can provide clinical timelines to achieve goals post-ACLR.•High quadriceps LSI without considering strength could overestimate patient recovery.
A backing detector for order-keV neutrons Biekert, A.; Chaplinsky, L.; Fink, C.W. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2022, Letnik:
1039
Journal Article
Recenzirano
Odprti dostop
We have designed and tested a large-area (0.15 m2) neutron detector based on neutron capture on 6Li. The neutron detector design has been optimized for the purpose of tagging the scattering angle of ...keV-scale neutrons. These neutron detectors would be employed to calibrate the low-energy (<100 eV) nuclear recoil in detectors for dark matter and coherent elastic neutrino nucleus scattering (CEνNS). We describe the design, construction, and characterization of a prototype. The prototype is designed to have a tagging efficiency of ∼25% at the relevant O(keV) neutron energies, and with a mean capture time of ∼17μs. The prototype was characterized using a 252Cf neutron source and agreement with the simulation was observed within a few percent level.
As part of a broader effort to calculate effective dose rate coefficients for external exposure to photons and electrons emitted by radionuclides distributed in air, soil or water, age-specific ...stylized phantoms have been employed to determine dose coefficients relating dose rate to organs and tissues in the body. In this article, dose rate coefficients computed using the International Commission on Radiological Protection reference adult male voxel phantom are compared with values computed using the Oak Ridge National Laboratory adult male stylized phantom in an air submersion exposure geometry. Monte Carlo calculations for both phantoms were performed for monoenergetic source photons in the range of 30 keV to 5 MeV. These calculations largely result in differences under 10 % for photon energies above 50 keV, and it can be expected that both models show comparable results for the environmental sources of radionuclides.
In order to provide secure clamping with a low thermal conductance, some low temperature detectors are held with point contact sapphire ball clamps. While this method is increasingly common, the ...thermal conductance across this interface has not been well studied. We present a direct measurement of the thermal conductance of such clamps between 200 and 600 mK, with a clamping force of approximately 2.7±0.3N/clamp. The thermal conductance of a single sapphire-on-copper clamp was found to be 660-210+360(T/K)3.1 nW/K. For a sapphire-on-silicon clamp the conductance was found to be 380-120+190(T/K)2.8 nW/K. The conductance measured is consistent with thermal boundary resistance.
Coherent elastic neutrino-nucleus scattering (CEνNS) offers a valuable approach in searching for physics beyond the standard model. The
Ricochet
experiment aims to perform a precision measurement of ...the CEνNS spectrum at the Institut Laue–Langevin nuclear reactor with cryogenic solid-state detectors. The experiment plans to employ an array of cryogenic thermal detectors, each with a mass of around 30 g and an energy threshold of below 100 eV. The array includes nine detectors read out by transition-edge sensors (TES). These TES-based detectors will also serve as demonstrators for future neutrino experiments with thousands of detectors. In this article, we present an update on the characterization and modeling of a prototype TES detector.
Properties of Low TC AlMn TES Wang, G.; Bratrud, G.; Chang, C. L. ...
Journal of low temperature physics,
2024/5, Letnik:
215, Številka:
3-4
Journal Article
Recenzirano
Low T
C
AlMn transition-edge sensors (TESs) have been developed as sensitive thermometers for the Q-Array, which will use superconducting targets to measure the coherent elastic neutrino nucleus ...scattering spectrum in the RICOCHET experiment. The TESs are made of manganese-doped aluminum with a titanium and gold antioxidation layer. A prototype TES thermometer consists of two TESs in parallel, an input gold pad in metallic contact with the TESs and an output gold pad and gold thermal link meanders, which are each designed to control the flow of heat through the TESs. We have fabricated and measured low T
C
AlMn TES chips with or without thermal flow control structures. We present T
C
measurements of the TESs after the initial fabrication and further T
C
tuning by re-heating and summarize the thermal property studies of the prototype TES thermometer by measuring I-V curves and complex impedance.
The Oak Ridge National Laboratory Center for Radiation Protection Knowledge has undertaken calculations related to various environmental exposure scenarios. A previous paper reported the results for ...submersion in radioactive air and immersion in water using age-specific mathematical phantoms. This paper presents age-specific effective dose rate coefficients derived using stylized mathematical phantoms for exposure to contaminated soils. Dose rate coefficients for photon, electron, and positrons of discrete energies were calculated and folded with emissions of 1252 radionuclides addressed in ICRP Publication 107 to determine equivalent and effective dose rate coefficients. The MCNP6 radiation transport code was used for organ dose rate calculations for photons and the contribution of electrons to skin dose rate was derived using point-kernels. Bremsstrahlung and annihilation photons of positron emission were evaluated as discrete photons. The coefficients calculated in this work compare favorably to those reported in the US Federal Guidance Report 12 as well as by other authors who employed voxel phantoms for similar exposure scenarios.
Results from a prototype TES detector for the Ricochet experiment Augier, C.; Baulieu, G.; Belov, V. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2023, Letnik:
1057
Journal Article
Recenzirano
Odprti dostop
Coherent elastic neutrino-nucleus scattering (CEνNS) offers valuable sensitivity to physics beyond the Standard Model. The Ricochet experiment will use cryogenic solid-state detectors to perform a ...precision measurement of the CEνNS spectrum induced by the high neutrino flux from the Institut Laue-Langevin nuclear reactor. The experiment will employ an array of detectors, each with a mass of ∼30 g and a targeted energy threshold of 50 eV. Nine of these detectors (the “Q-Array”) will be based on a novel Transition-Edge Sensor (TES) readout style, in which the TES devices are thermally coupled to the absorber using a gold wire bond. We present initial characterization of a Q-Array-style detector using a 1 gram silicon absorber, obtaining a baseline root-mean-square resolution of less than 40 eV.
The future
Ricochet
experiment aims at searching for new physics in the electroweak sector by providing a high precision measurement of the Coherent Elastic Neutrino-Nucleus Scattering (CENNS) ...process down to the sub-100 eV nuclear recoil energy range. The experiment will deploy a kg-scale low-energy-threshold detector array combining Ge and Zn target crystals 8.8 m away from the 58 MW research nuclear reactor core of the Institut Laue Langevin (ILL) in Grenoble, France. Currently, the
Ricochet
Collaboration is characterizing the backgrounds at its future experimental site in order to optimize the experiment’s shielding design. The most threatening background component, which cannot be actively rejected by particle identification, consists of keV-scale neutron-induced nuclear recoils. These initial fast neutrons are generated by the reactor core and surrounding experiments (reactogenics), and by the cosmic rays producing primary neutrons and muon-induced neutrons in the surrounding materials. In this paper, we present the
Ricochet
neutron background characterization using
3
He proportional counters which exhibit a high sensitivity to thermal, epithermal and fast neutrons. We compare these measurements to the
Ricochet
Geant4 simulations to validate our reactogenic and cosmogenic neutron background estimations. Eventually, we present our estimated neutron background for the future
Ricochet
experiment and the resulting CENNS detection significance. Our results show that depending on the effectiveness of the muon veto, we expect a total nuclear recoil background rate between 44 ± 3 and 9 ± 2 events/day/kg in the CENNS region of interest, i.e. between 50 eV and 1 keV. We therefore found that the
Ricochet
experiment should reach a statistical significance of 4.6 to 13.6
σ
for the detection of CENNS after one reactor cycle, when only the limiting neutron background is considered.
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