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PURPOSE: The aim of this study was to analyse clinical, functional and shoulder kinematics results using subacromial balloon spacer in nonreparable massive rotator cuff tears. Subacromial balloon spacer was hypothesised to improve shoulder kinematics and increases clinical and functional outcomes scores in nonreparable massive rotator cuff tears. METHODS: This is a prospective study in massive rotator cuff tears. From October 2021 to October 2022, a total of 127 shoulders suffering massive rotator cuff tears were initially evaluated. All patients were evaluated preoperatively, at 6 and 12 months. Patients' patient-reported outcome measures (PROM) subjective values using visual analogue scale (VAS) and the Spanish Western Ontario Rotator Cuff Index (WORC) version were analysed. We also evaluated objective outcomes: constant score, range of movement and kinematic shoulder analysis (isokinetic test to evaluate internal and external rotation forces). Statistical analysis was conducted using SPSS software; continuous variables were presented as means and standard deviations (SDs). RESULTS: Seventeen nonrepairable massive rotator cuff tears were finally included. Three patients required reverse shoulder arthroplasty before 6 months postoperative. After 1-year follow-up, objective and subjective (PROM) outcome scores and isokinetic measurements improved in 13 patients. Preoperative VAS improved from 6.5 ± 2.1 to 2 ± 1.9 points on average at 1-year follow-up and WORC index from 1603 ± 217.3 to 699 ± 361.6. Constant score from 42.1 ± 13.1 on average and at 1-year follow-up increased to 60.8 ± 14.7. Range of movement also improved in elevation 122.2 ± 39.3 to 166.9 ± 25.8, abduction 120.3 ± 38.6 to 134.6 ± 21.1, external rotation 30.3 ± 19.7 to 86.1 ± 13.8 and internal rotation L4-T12 on average at 1-year follow-up. Isokinetic evaluation showed functional improvement 1 year after implantation. Both internal and external rotation improved compared with their healthy shoulder. External rotation improved from 30.3° ± 19.7° preoperatively to 86.1° ± 13.8° (43.7% in the isokinetic study) and internal rotation from L4 preoperatively to L1 (49.8% in isokinetic study) on average. CONCLUSION: Among the different alternatives for irreparable rotator cuff injuries surgical treatment, subacromial balloon spacer is an effective alternative in selected patients, both in terms of clinical-functional improvement and short-term isokinetic results. LEVEL OF EVIDENCE: Level II.

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Conductive hydrogels with excellent mechanical properties, a broad detection range, and stability in complex environments have remained a significant challenge for the development of flexible sensors. In this study, a straightforward freeze-thaw cycles strategy was developed to fabricate a polyvinyl alcohol (PVA)/carrageenan (CA)/calcium chloride (CaCl2)/MXene-based double network organohydrogel (PCCME) for highly flexible and responsive strain detection across a broad temperature spectrum. The PCCME organohydrogel features multiple interactive forces including hydrogen bonding, ionic interactions, and microphase crystallization, which contribute to the organohydrogel's exceptional mechanical and electrical performance. The PCCME organohydrogel exhibited excellent performance in a load-unload test repeated 100 times after being maintained at room temperature for 7 days, with a minimal mechanical decay of only 2.6%. Furthermore, the repaired PCCME organohydrogel retained its robust stability after storage at low temperatures followed by placement at room temperature. The organohydrogel sensor not only detects various movement amplitudes of the human body but also recognizes arrays of pressure signals and converts these into digital images, highlighting its significant potential for applications in rehabilitation monitoring, pressure sensing, and human-computer interaction.

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Carbon materials are a category of broadband solar energy harvesting materials that can convert solar energy into heat under irradiation, which can be used for photothermal water evaporation and photothermoelectric power generation. However, destruction of the carbon nanostructure during usage will significantly decrease the light-trapping performance and, thus, limit their practical applications. In this article, an easily repairable carbon nanostructure absorber with full-solar-spectrum absorption and a hierarchically porous structure is prepared. The carbon absorber shows a superhigh light absorption of above 97% across the whole solar spectrum because of multiple scatterings within the carbon nanostructure and photon interaction with the carbon nanoparticles. The excellent light absorption performance directly leads to a good photothermal effect. As a consequence, the carbon absorber integrated with a thermoelectric module can obtain a large power (133.3 µW cm-2) output under 1 sun. In addition, the carbon absorber combined with the sponge can achieve a high photothermal water evaporation efficiency of 83.6% under 1 sun. Its high-efficiency solar-to-electricity and photothermal water evaporation capabilities demonstrate that the carbon absorber with superhigh absorption, simple fabrication, and facile repairability shows great potential for practical fresh water production and electric power generation.

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Self-limiting assembly of particles represents the state-of-the-art controllability in nanomanufacturing processes where the assembly stops at a designated stage, providing a desirable platform for applications requiring delicate thickness control such as optics, electronics, and catalytic systems. Most successes in self-limiting assembly are limited to self-assembled monolayers (SAMs) of small molecules on inorganic, chemically homogeneous rigid substrates (e.g., Au and SiO2) through surface-interaction mechanisms. Similar mechanisms, however, cannot achieve a uniform assembly of particles on flexible polymer substrates. The complex configurations and conformations of polymer chains create a surface with nonuniform distributions of chemical groups and phases. In addition, most assembly mechanisms require good solvent wettability, where many desirable but hard-to-wet particles and polymer substrates are excluded. Here, we demonstrate a collision-based self-limiting assembly (CSA) to achieve wafer-scale, full-coverage, close-packed monolayers of hydrophobic particles on hydrophobic polymer substrates in aqueous solutions. The kinetic assembly and self-limiting processes are facilitated and controlled by the combined acoustic and shear fields. We envision many applications in functional coatings and showcase their feasibility in structural coloration. Importantly, such functional coatings can be repaired using CSA, and both particles and polymer substrate can be recycled.

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Heart transplant surgery is considered the destination therapy for end-stage heart disease. Unfortunately, many patients in the United States of America who are eligible candidates for transplants cannot undergo surgery due to donor shortage. In addition, some donors' hearts are being labeled as unacceptable for transplant surgery because of the rigorous and restricted rules placed on the approval process of using a donor's heart. Over the last few decades, the rising discrepancy between the scarcity of donor hearts and the demand for such organs has led to the discussion of expanding the donor heart selection criteria. A softer view on using marginal hearts for transplants would help those on the waitlist to receive a heart transplant. Marginal hearts that contain the hepatitis c virus (HCV), COVID-19, older age, or repairable heart defects have become viable options to use for a heart transplant. Also, the prioritization based on the new heart allocation system would help efficiently decide which recipients would be the first to get a donor's heart. Recently there has been a consensus to broaden the eligibility of donor's hearts by accepting valvular abnormalities, coronary artery disease, and congenital abnormalities. This review highlights some of those expansions in selection criteria in particular using repairable hearts, which could be fixed in the operating room on the back table before transplantation.

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BACKGROUND: Adults presenting with an unrepaired atrial septal defect and pulmonary arterial hypertension (ASD-PAH) are typically classified as "correctable" or "non-correctable". The use of directed PAH medical therapy in non-correctable ASD-PAH leading to favorable closure candidacy, repair status and long-term follow-up is not well studied. We therefore sought to characterize response to PAH targeted therapy in 'non-correctable' ASD-PAH. METHODS AND RESULTS: Nine North American tertiary care centers submitted retrospective data from adults with unrepaired ASD-PAH that did not meet recommendations for repair at initial presentation (1996-2017). Sixty-nine patients (women 51(74%), 40 ±â€¯15 years, mean pulmonary artery pressure (mPA) 51 ±â€¯13 mm Hg, pulmonary vascular resistance (PVR) 8.7 ±â€¯4.9 Wood units, Qp:Qs 1.6 ±â€¯0.4) were enrolled. All patients were prescribed PAH targeted therapy and late shunt repair occurred in 19(28%) (Women 15(29%) vs. Men 4(22%), p = 0.6). At late follow-up (4.4 ±â€¯2.9 years) 6-minute walk test distance (6MWTD) was significantly better in the group that underwent repair (486 ±â€¯89 m vs. 375 ±â€¯139 m, p < 0.05). Transthoracic echo showed significant improvement in right ventricular (RV) function (severe dysfunction in repaired 8(40%) vs. unrepaired groups 35(69%), p < 0.05). Divergent survival curves suggest that with larger studies and more follow-up, differences in survival between repaired and unrepaired groups may be important. (repaired: 17(94%) vs. unrepaired: 32(81%), p = 0.18). CONCLUSIONS: This is the first and largest multicenter study evaluating the "treat-to-close" approach in non-correctable ASD-PAH. Our new data supports further study of this strategy in patients who have reversibility of PAH in response to targeted therapy. We demonstrate that in the carefully selected patient with non-correctable ASD-PAH, successful shunt repair is possible if post-therapy PVR is ≤6.5 Wood units. Patients who underwent repair had improved RV function following PAH targeted therapy. Divergent survival curves suggest that with further study, defect repair may affect medium-term to late survival.

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Defectos del Tabique Interatrial/epidemiología , Defectos del Tabique Interatrial/cirugía , Hipertensión Arterial Pulmonar/epidemiología , Hipertensión Arterial Pulmonar/cirugía , Sistema de Registros , Adulto , Femenino , Defectos del Tabique Interatrial/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , América del Norte/epidemiología , Hipertensión Arterial Pulmonar/diagnóstico por imagen , Estudios Retrospectivos , Resultado del Tratamiento , Prueba de Paso/métodos

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Conventional thermoset coatings cannot be easily repaired and removed owing to their highly crosslinked structure. The investigation of repairable or removable coatings has been receiving extensive attention, but few reported coatings possess both features. In this work, a repairable and removable coating was developed through the curing of a modified Kraft lignin (L-COOH) with poly(ethylene glycol) diglycidyl ether (PEG-epoxy) in the presence of zinc catalyst. The L-COOH was prepared by functionalization of Kraft lignin with carboxylic acid groups. The cured material had a high lignin content (>47 wt %). At elevated temperatures (>140 °C), dynamic transesterification in the cured network was activated, which resulted in fast stress relaxation and imparted excellent repairability. If the vitrimer system was used as a coating for tin plates, it provided adequate hardness and adhesion properties. In addition, the lignin-PEG coating could be easily removed from the tin plate by using a mild (0.01-0.1 m) NaOH aqueous solution owing to the unique swelling ability of the coating in alkaline aqueous solution. With the assistance of ethylene glycol, this coating could achieve stress-free repairability in 15 min. This work demonstrates the first lignin-based repair- and removable epoxy coating based on vitrimer chemistry.

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Bird feathers have aroused tremendous attention for their superdurability against tears during long flights through wind and even bushes. Although feathers may inevitably be unzipped, the separated feather vanes can be repaired easily by bill stroking. However, the mechanism underlying bird feathers' superdurability against tears remains unclear. Here, we reveal that the superdurability of bird feathers arises from their repairable cascaded slide-lock system, which is composed of hooklets, a slide rail, and spines at the end of the slide rail as terminating structures. Microscopy with a micronano manipulating system and 3D X-ray microscopy provided high-level visibility into the 3D fine structures and the entire unzipping process of feathers. The hooklets can slide along the slide rail reversibly when suffering external forces, and the sliding hooklet can be locked by the spine at the ends of barbules when larger pulling forces are applied and even slide farther away due to the unzipping of the interlocking structure with large deformation of the barbules. The elongation before separation of adjacent barbs can reach up to 270%, and the separation force can be maintained above 80% of the initial value even after 1,000 cycles of separating and repairing. These results prove that the cascaded slide-lock system ensures the superdurability of bird feathers against tears.

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Aves/anatomía & histología , Plumas/ultraestructura , Animales

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In nature, self-healing can be induced by sunlight for damage and wound repair, and this phenomenon is very important to living species for prolonging their lives. This self-repairing feature is obviously highly desirable for non-biological materials and manmade systems. In this paper, we demonstrate, for the first time, that battery electrodes can be self-repaired when exposed to sunlight. Here, we show that the optical, and photoelectrochemical (PEC) properties can be controlled by varying structural and compositional parameters of copper selenide nanocrystals (NCs). Cation to anion ratio in copper selenide (Cu2±xSe) NCs can be controlled over a wide range of 1.3-2.7 by simply changing the reaction temperature and impurity. Light-induced self-repairable behavior is demonstrated with electrochemical (EC) and PEC performances of electrodes made with stoichiometric copper selenide NCs. This nature-inspired, self-repairing behavior can be applied to batteries, supercapacitors, and photo-electrochemical fuel generators.

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In this paper, a new family of binary LRCs (BLRCs) with locality 2 and uneven availabilities for hot data is proposed, which has a high information symbol availability and low parity symbol availabilities for the local repair of distributed storage systems. The local repair of each information symbol for the proposed codes can be done not by accessing other information symbols but only by accessing parity symbols. The proposed BLRCs with k = 4 achieve the optimality on the information length for their given code length, minimum Hamming distance, locality, and availability in terms of the well-known theoretical upper bound.

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A simple way of chemical etching with H2SO4 and H2O2 was employed to prepare a superhydrophobic steel surface with a water contact angle of 163.5° and a sliding angle of about 0°, in addition to modification with 1H,1H,2H,2H-perfluoroalkyltriethoxysilane (FAS-13). On the basis of perfluropolyethers (PFPE) infusion, a slippery liquid-infused porous surface (SLIPS) was fabricated that had a water contact angle of 115.6° and a sliding angle of 2.27°. The prepared sample can still maintain superhydrophobicity after moving 100 cm on 1000 # sandpaper under 100 g loading via an abrasion test, while its corrosion resistance was exhibited via more positive corrosion potentials (Ecorr) and lower corrosion current densities (Icorr) in electrochemical corrosion tests with various solutions. Even if superhydrophobic and slippery properties were lost in the process of long-time soaking in salt solution, the superhydrophobic steel could regain its ability and slippery surfaces also exhibited the repairable durability through retreatment. Such stable, corrosion resistant and superhydrophobic bearing steel and repairable slippery surface have potential for application in practical production and life.

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Ultra-broad-band electromagnetic absorption materials and structures are increasingly attractive for their critical role in competing with the advanced broad-band electromagnetic detection systems. Mechanically soft and weak wax-based materials composites are known to be insufficient to serve in practical electromagnetic absorption applications. To break through such barriers, here we developed an innovative strategy to enable the wax-based composites to be robust and repairable meta-structures by employing a three-dimensional (3D) printed polymeric patterned shell. Because of the integrated merits from both the dielectric loss wax-based composites and mechanically robust 3D printed shells, the as-fabricated meta-structures enable bear mechanical collision and compression, coupled with ultra-broad-band absorption (7-40 and 75-110 GHz, reflection loss  smaller than -10 dB) approaching state-of-the-art electromagnetic absorption materials. With the assistance of experiment and simulation methods, the design advantages and mechanism of employing such 3D printed shells for substantially promoting the electromagnetic absorption performance have been demonstrated. Therefore, such universal strategy that could be widely extended to other categories of wax-based composites highlights a smart stage on which high-performance practical multifunction meta-structures with ultra-broad-band electromagnetic absorption could be envisaged.

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Superhydrophobic (SHP) coatings inspired by lotus have great application prospect for our daily life. Regrettably, three formidable challenges, namely, complex fabrication, weak mechanical stability and large-scale fabrication, have already existed for a long time in this research field. Here, a robust micro-nanoscale P25 (Nano TiO2)/MgO/epoxy resin (ER) SHP coating has been fabricated via facile one-pot route, which can be applied to arbitrary substrates through multiples methods. P25/MgO/ER SHP coating not only displays excellent mechanical stability but also shows unique repairable ability to recover its superhydrophobicity under various damages by extreme environment such as low temperature, strong acid or alkali and this repairable process can be repeated for many times. P25/MgO/ER SHP coating also is easy to large-scale fabrication with very low cost.

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In this article we develop a model for determining the appropriate level of inspection sampling for any manufacturing process. The model is useful for manufacturers, who naturally are concerned with profits and therefore with minimizing the cost of production. The model design aims to reduce total manufacturing cost and has general applicability to various manufacturing operations. The model considers the interests of consumers, who wish to minimize the cost of production while simultaneously ensuring the final product is of high quality. The cost parameters for production, the acceptance test, and admissible strategy are applied in the model. The cost components are formulated along with the minimization of the expected cost, and we used the repairable systems to guarantee the maintenance and sustainability of the economic system. We also discuss the assumptions and their appropriateness, as well as the application of the model to burn-in of system components.

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The instant system availability [Formula: see text] of a repairable system with the renewal equation was studied. The starting point monotonicity of [Formula: see text] was proved and the upper bound of [Formula: see text] is also derived. It was found that the interval of instant system availability monotonically decreases. In addition, we provide examples that validate the analytically derived properties of [Formula: see text] based on the Lognormal, Gamma and Weibull distributions and the results show that the value of T is slightly smaller than its value defined in Theorem 2. The procedure of using a bathtub as application for this article is also discussed.

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Rotator cuff lesions (RCL) have considerable variability in location, tear pattern, functional impairment, and repairability.Historical classifications for differentiating these lesions have been based upon factors such as the size and shape of the tear, and the degree of atrophy and fatty infiltration. Additional recent descriptions include bipolar rotator cuff insufficiency, 'Fosbury flop tears', and musculotendinous lesions.Recommended treatment is based on the location of the lesion, patient factors and associated pathology, and often includes personal experience and data from case series. Development of a more comprehensive classification which integrates historical and newer descriptions of RCLs may help to guide treatment further. Cite this article: Lädermann A, Burkhart SS, Hoffmeyer P, et al. Classification of full thickness rotator cuff lesions: a review. EFORT Open Rev 2016;1:420-430. DOI: 10.1302/2058-5241.1.160005.

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The present work investigates the various reliability parameters of industrial systems in terms of membership and non-membership functions by using α-cut and the weakest t-norm based arithmetic operations on triangular intuitionistic fuzzy sets. As the available information about the constituent components of the system is most of the time imprecise, incomplete, vague and conflicting, the management decisions are based on experience. Thus, the objective of this paper is to quantify the uncertainties that make the decisions realistic, generic and extensible for the application domain. Sensitivity of system performance has also been analyzed for showing the effect of taking wrong combinations of reliability parameters. The obtained results computed by the proposed approach are compared with the existing methodologies. The approach has been illustrated through a case study for supremacy.

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Traditionally, in the redundancy allocation problem (RAP), two general classes of optimization problems are considered; reliability optimization and availability optimization. Contrary to reliability optimization, fewer researchers have studied availability optimization to find out the optimal combination of components type and redundancy levels for each subsystem in a system for maximizing (or minimizing) the objectives. In each problem it is assumed that either the entire components are repairable or they are non-repairable. However, in real world situations, systems usually consist of both repairable and non-repairable components. In this paper a new Mixed Integer Nonlinear Programming (MINLP) model is presented to analyze the availability optimization of a system with a given structure, using both repairable and non-repairable components, simultaneously. To find the solution of the introduced MINLP, an efficient Genetic Algorithm (GA) is also developed. Furthermore, to show the efficiency of the proposed GA, a numerical example is presented. Experimental results demonstrate that the proposed GA has a better performance compared to one of the most recommended algorithm in the literature.

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The main objective of this paper is to present a technique for computing the membership functions of the intuitionistic fuzzy set (IFS) by utilizing imprecise, uncertain and vague data. In literature so far, membership functions of IFS are computed via using fuzzy arithmetic operations within collected data and hence contain a wide range of uncertainties. Thus it is necessary for optimizing these spread by formulating a nonlinear optimization problem through ordinary arithmetic operations instead of fuzzy operations. Particle swarm optimization (PSO) has been used for constructing their membership functions. Sensitivity as well as performance analysis has also been conducted for finding the critical component of the system. Finally the computed results are compared with existing results. The suggested framework has been illustrated with the help of a case.

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A resource-efficient approach to making inferences about the distributional properties of the failure times in a competing risks setting is presented. Efficiency is gained by observing recurrences of the competing risks over a random monitoring period. The resulting model is called the recurrent competing risks model (RCRM) and is coupled with two repair strategies whenever the system fails. Maximum likelihood estimators of the parameters of the marginal distribution functions associated with each of the competing risks and also of the system lifetime distribution function are presented. Estimators are derived under perfect and partial repair strategies. Consistency and asymptotic properties of the estimators are obtained. The estimation methods are applied to a data set of failures for cars under warranty. Simulation studies are used to ascertain the small sample properties and the efficiency gains of the resulting estimators.