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Introduction: Breast cancer disease often affects the ipsilateral shoulder joint, with pain and joint limitation. Proper pain management, which can be obtained using, for example, pulsed radiofrequency of the suprascapular nerve, can help the physiotherapist mitigate patient pain. The modern technologies of kinematic analysis and surface electromyography of movement analysis can give further support in building a personalized rehabilitation program, based on the quantitative study of movement, in this case of the upper limb. Methods: A brief case report was conceived to develop and test the evolution of a shoulder joint analysis protocol based on an inertial accelerometer and noninvasive surface electromyography. Results: An analysis algorithm was defined to adapt to the needs of patients operated on at the breast based on a kinematic component (ROM - range of movement - and Jerk index) and an electromyographic one (study of muscle behavior in groups of four). The coactivations were also evaluated, both as an average value and in graphical form, to offer the physiotherapist a complete overview of the movement of the upper limb. Discussion: The promising protocol results underline its strengths, including the simplicity of use, combined with the reduced time required for processing the reports and the portability of the PC-sensors complex, making these analyses potentially valuable for patient care. [ABSTRACT FROM AUTHOR]

Proximal humerus fractures are common injuries and the development of nonunion or malunion is infrequent. However, these complications can occur with both operative and non-operative treatment of the fracture. A complete evaluation of these patients must include an investigation of the original fracture, bone and soft tissue quality as well as an extensive radiological study with X-Ray, CT and MRI. Asymptomatic and low demanding patients can benefit from conservative treatment, otherwise surgery is necessary. Multiple treatment options exist with no consensus upon the gold standard. The management of these complications is case-specific and needs extensive pre-operative planning. Arthroscopic procedures, osteotomies and bone grafting are viable joint preservation techniques. Bone loss or articular pathology are indications for joint replacement. The surgical treatment of nonunion and malunion is challenging even for experienced surgeons. [ABSTRACT FROM AUTHOR]

Abstract: Perovskite/silicon tandem solar cells are increasingly recognized as promi­sing candidates for next‐generation photovoltaics with performance beyond the single‐junction limit at potentially low production costs. Current designs for monolithic tandems rely on transparent conductive oxides as an intermediate recombination layer, which lead to optical losses and reduced shunt resistance. An improved recombination junction based on nanocrystalline silicon layers to mitigate these losses is demonstrated. When employed in monolithic perovskite/silicon heterojunction tandem cells with a planar front side, this junction is found to increase the bottom cell photocurrent by more than 1 mA cm−2. In combination with a cesium‐based perovskite top cell, this leads to tandem cell power‐conversion efficiencies of up to 22.7% obtained from J–V measurements and steady‐state efficiencies of up to 22.0% during maximum power point tracking. Thanks to its low lateral conductivity, the nanocrystalline silicon recombination junction enables upscaling of monolithic perovskite/silicon heterojunction tandem cells, resulting in a 12.96 cm2 monolithic tandem cell with a steady‐state efficiency of 18%. [ABSTRACT FROM AUTHOR]

Bilayers of intrinsic and doped hydrogenated amorphous silicon, deposited on crystalline silicon (c-Si) surfaces, simultaneously provide contact passivation and carrier collection in silicon heterojunction solar cells. Recently, we have shown that the presence of overlaying transparent conductive oxides can significantly affect the c-Si surface potential induced by these amorphous silicon stacks. Specifically, deposition on the hole-collecting bilayers can result in an undesired weakening of contact passivation, thereby lowering the achievable fill factor in a finished device. We test here a variety of organic semiconductors of different doping levels, overlaying hydrogenated amorphous silicon layers and silicon-based hole collectors, to mitigate this effect. We find that these materials enhance the c-Si surface potential, leading to increased implied fill factors. This opens opportunities for improved device performance. [ABSTRACT FROM AUTHOR]

Substituting the doped amorphous silicon films at the front of silicon heterojunction solar cells with wide-bandgap transition metal oxides can mitigate parasitic light absorption losses. This was recently proven by replacing p-type amorphous silicon with molybdenum oxide films. In this article, we evidence that annealing above 130°C--often needed for the curing of printed metal contacts-- detrimentally impacts hole collection of such devices. We circumvent this issue by using electrodeposited copper front metallization and demonstrate a silicon heterojunction solar cell with molybdenum oxide hole collector, featuring a fill factor value higher than 80% and certified energy conversion efficiency of 22.5%. [ABSTRACT FROM AUTHOR]

Thin, light-absorbing films attenuate the Raman signal of underlying substrates. In this article, we exploit this phenomenon to develop a contactless thickness profiling method for thin films deposited on rough substrates. We demonstrate this technique by probing profiles of thin amorphous silicon stripes deposited on rough crystalline silicon surfaces, which is a structure exploited in high-efficiency silicon heterojunction solar cells. Our spatially-resolved Raman measurements enable the thickness mapping of amorphous silicon over the whole active area of test solar cells with very high precision; the thickness detection limit is well below 1 nm and the spatial resolution is down to 500 nm, limited only by the optical resolution. We also discuss the wider applicability of this technique for the characterization of thin layers prepared on Raman/photoluminescence-active substrates, as well as its use for single-layer counting in multilayer 2D materials such as graphene, MoS2 and WS2. [ABSTRACT FROM AUTHOR]

Hydrogenated nanocrystalline silicon (nc-Si:H) is a multiphase, heterogeneous material, composed of Si nanocrystals embedded in an amorphous matrix. It has been intensively studied in the last few years due to its great promise for photovoltaic and optoelectronics applications. The present paper aims to study the current transport mechanisms in nc-Si:H by mapping the local conductivity at the nanoscale. The role of B doping in nc-Si:H is also investigated. Conductivity maps are obtained by atomic force microscopy using a conductive tip. Differences and similarities between intrinsic and doped nc-Si:H conductivity maps were observed and these are also explained on the basis of recently published computational studies. [ABSTRACT FROM AUTHOR]

Conductive atomic force microscopy (C-AFM) has been extensively used for making measurements of electrical properties of nanostructures, devices and multiphase materials. Despite its wide use, the mechanical and electrical interactions at the nanoscale between the tip and the sample surface are not yet well understood. These phenomena should be carefully studied and modeled in order to avoid significant measurement artifacts. In the present contribution a study of the interactions occurring between conductive tips and the surface of nanocrystalline silicon thin films that lead to measurement artifacts is presented. A significant deterioration of the tip coating was detected after a few maps, resulting in meaningless maps. The features of the map obtained dramatically depend on the tip coating characteristics and on the load conditions. Moreover, under a constant bias voltage, the electrical current passing through the tip-sample junction degenerates strongly with time. These phenomena were interpreted by considering the effect of strong electric fields present during C-AFM experiments.