OBJECTIVE:To assess the efficacy of conservative management of women with femoroacetabular impingement (FAI) using trunk stabilization.
DESIGN:Randomized controlled trial (level of evidenceI).
...SUBJECTS:Twenty FAI female patients who met the inclusion FAI criteria.
METHODS:A prospective, randomized, controlled study was performed on 20 female patients with symptomatic FAI comprising 2 groups (10 hips in trunk stabilization exercise group vs 10 hips in control group). We evaluated hip range of motion, isometric muscle strength using a handheld dynamometer (μ-TasMF-01; Anima, Co), and patient-reported outcome measures, including modified Harris hip score, Vail hip score, and international hip outcome tool 12 (iHOT12) before and at 4 weeks and 8 weeks after the intervention.
RESULTS:There was a significant improvement in the range of motion of hip flexion in the trunk training group detected as early as 4 weeks after the intervention compared with the control group (P < 0.05). Hip abductor strength significantly improved in the trunk training group at 4 weeks after the intervention, whereas it did not improve in the control group (P < 0.05). Vail hip score and iHOT12 were significantly increased at 8 weeks after the intervention in the trunk training group compared with the control group (iHOT1278.7 ± 22.4 vs 53.0 ± 22.3; P < 0.01, Vail hip score81.6 ± 18.5 vs 61.1 ± 11.6; P < 0.05). There was no significant difference in the modified Harris hip score between both the groups at 4 and 8 weeks after the intervention.
CONCLUSIONS:The addition of trunk stabilization exercise to a typical hip rehabilitation protocol improves short-term clinical outcomes and may augment nonoperative and postoperative rehabilitation.
Purpose
It was the aim to assess all published original research dealing with dynamic repair of the anterior cruciate ligament (ACL) and to provide a semi-quantitative analysis of clinical outcome ...reports.
Methods
Both OVIS and MEDLINE databases were utilized for allocation of articles. All preclinical and clinical studies related to dynamic intraligamentary stabilization (DIS) were identified. Results were tabulated and semi-quantitative analysis performed.
Results
Twenty-three articles related to DIS were identified. The predominant level of evidence ranged between II and IV, with only one level I study. Reported failure rates ranged between 4% and 13.6%. Most clinical studies only reported revision rates without referring to failure of restoring stability. Highest success was achieved with proximal ACL ruptures. Both the level of physical activity and patient age have been found to influence the risk of failure.
Conclusion
There is sufficient evidence to support that DIS repair may be an effective modality for the treatment of acute proximal tears of the ACL. However, comparative studies are lacking. Upcoming studies should compare the technique to ACL reconstruction with failure as an endpoint. Comparison to rigid methods of proximal fixation is also necessary to justify the need for dynamic fixation. Overall, there is evidence to suggest the potential space for ACL repair in the decision tree for individualized treatment planning. The best outcome will be in the hands of the best patient selectors.
Level of evidence
IV.
In this paper, we study a class of memristive neural networks with mixed delays. The existence of its equilibrium point is proved without the boundedness and initial value of the activation function, ...and a criterion to ensure its exponential stabilization under a sampled‐data controller is obtained by constructing an appropriate Lyapunov function. Meanwhile, the fixed‐time stabilization of memristive neural networks is also proved by the Lyapunov method. The obtained results extend and enhance some existing ones, and are illustrated by numerical examples.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Manipulating the active species and improving the structural stabilization of sulfur‐containing catalysts during the OER process remain a tremendous challenge. Herein, we constructed NiO/NiS2 and ...Fe−NiO/NiS2 as catalyst models to study the effect of Fe doping. As expected, Fe−NiO/NiS2 exhibits a low overpotential of 270 mV at 10 mA cm−2. The accumulation of hydroxyl groups on the surface of materials after Fe doping can promote the formation of highly active NiOOH at a lower OER potential. Moreover, we investigated the level of corrosion of M−S bonds and compared the stability variation of M−S bonds with Fe at different locations. Interestingly, Fe bonded with S in the bulk as the sacrificial agent can alleviate the oxidation corrosion of partial Ni−S bonds and thus endow Fe−NiO/NiS2 long‐term durability. This work could motivate the community to focus more on resolving the corrosion of sulfur‐containing materials.
Bulk doped Fe not only accelerates the surface reconstruction of NiO/NiS2 into the active NiOOH phase at a lower oxygen evolution reaction (OER) overpotential but also alleviates the oxidation corrosion of partial Ni−S bonds to provide a promising way to balance the activity and stability of sulfur‐containing materials in the OER process.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Dispersion stability of thermal nanofluids Yu, Fan; Chen, Yingying; Liang, Xingbo ...
Progress in Natural Science/Progress in natural science,
10/2017, Volume:
27, Issue:
5
Journal Article
Peer reviewed
Open access
Thermal nanofluids, the engineered fluids with dispersed functional nanoparticles, have exhibited extraordinary thermophysical properties and added functionalities, and thus have enabled a broad ...range of important applications. The poor dispersion stability of thermal nanofluids, however, has been considered as a longexisting issue that limits their further development and practical application. This review overviews the recent efforts and progresses in improving the dispersion stability of thermal nanofluids such as mechanistic understanding of dispersion behavior of nanofluids, examples of both water-based and oil-based nanofluids,strategies to stabilize nanofluids, and characterization techniques for dispersion behavior of nanofluids. Finally,on-going research needs, and possible solutions to research challenges and future research directions in exploring stably dispersed thermal nanofluids are discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article studies fixed-time stabilization (FxTS) of a general controllable linear system with an input delay <inline-formula><tex-math notation="LaTeX">\tau</tex-math></inline-formula>. It is ...shown that such a problem is not solvable if the prescribed convergence time <inline-formula><tex-math notation="LaTeX">T_{\tau }</tex-math></inline-formula> is smaller than <inline-formula><tex-math notation="LaTeX">2\tau</tex-math></inline-formula>. For <inline-formula><tex-math notation="LaTeX">T_{\tau }\geq 3\tau</tex-math></inline-formula>, a solution based on linear periodic delayed feedback (PDF) without any distributed delay is established. For <inline-formula><tex-math notation="LaTeX">T_{\tau }>2\tau</tex-math></inline-formula>, a solution based on linear predictor-based PDF containing a distributed delay is proposed. For both cases, the gains of the PDF can be chosen as continuous, continuously differentiable, and even smooth, in the sense of infinitely many times differentiable. If only an output signal is available for feedback, two classes of linear observers with periodic coefficients are designed, so that their states converge to the current and future states of the system at a prescribed finite time, respectively. With the observed current and future states, FxTS can also be achieved by using, respectively, the PDF and observer-based PDF. A linear periodic feedback (without delay) is also established to solve the FxTS problem of linear systems with both instantaneous and delayed controls, which cannot be stabilized by any constant instantaneous feedback in certain cases. Two numerical examples verify the effectiveness of the proposed approaches.
The stabilization of probabilistic Boolean networks with pinning control is investigated. Only a part of nodes are chosen to be controlled for the aim of high efficiency. Stabilization with ...probability one and stabilization in probability are respectively discussed. Since the probability of stabilization is not required to be strict one, stabilization in probability is a more practical extension of the former, which is also proven in this work. Stabilization with probability one needs the target state to be transferred to itself with 100% certainty, while stabilization in probability cannot even guarantee the existence of such a possibility. Thus, stabilization in probability is a different and challenging problem. Some necessary and sufficient conditions are proposed for both types of stabilization via the semi-tensor product of matrices. Based on them, approaches to controller design are also developed. Finally, illustrative examples are provided to demonstrate the effectiveness of the derived results.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper deals with a sum-of-squares (SOS)-based control Lyapunov function (CLF) design for polynomial fuzzy control of nonlinear systems. The design starts with exactly replacing (smooth) ...nonlinear systems dynamics with polynomial fuzzy models, which are known as universal approximators. Next, global stabilization conditions represented in terms of SOS are provided in the framework of the CLF design, i.e., a stabilizing controller with nonparallel distributed compensation form is explicitly designed by applying Sontag's control law, once a CLF for a given nonlinear system is constructed. Furthermore, semiglobal stabilization conditions on operation domains are derived in the same fashion as in the global stabilization conditions. Both global and semiglobal stabilization problems are formulated as SOS optimization problems, which reduce to numerical feasibility problems. Five design examples are given to show the effectiveness of our proposed approach over the existing linear matrix inequality and SOS approaches.