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We study theoretically electron interference in a Mach-Zehnder-like geometry formed by four zigzag graphene nanoribbons (ZGNRs) arranged in parallel pairs, one on top of the other, such that they form intersection angles of 60º. Depending on the interribbon separation, each intersection can be tuned to act either as an electron beam splitter or as a mirror, enabling tuneable circuitry with interfering pathways. Based on the mean-field Hubbard model and Green's function techniques, we evaluate the electron transport properties of such 8-terminal devices and identify pairs of terminals that are subject to self-interference. We further show that the scattering matrix formalism in the approximation of independent scattering at the four individual junctions provides accurate results as compared with the Green's function description, allowing for a simple interpretation of the interference process between two dominant pathways. This enables us to characterize the device sensitivity to phase shifts from an external magnetic flux according to the Aharonov-Bohm effect as well as from small geometric variations in the two path lengths. The proposed devices could find applications as magnetic field sensors and as detectors of phase shifts induced by local scatterers on the different segments, such as adsorbates, impurities or defects. The setup could also be used to create and study quantum entanglement.

Precise control over the size and shape of graphene nanostructures allows engineering spin-polarized edge and topological states, representing a novel source of non-conventional π-magnetism with promising applications in quantum spintronics. A prerequisite for their emergence is the existence of robust gapped phases, which are difficult to find in extended graphene systems. Here we show that semi-metallic chiral GNRs (chGNRs) narrowed down to nanometer widths undergo a topological phase transition. We fabricated atomically precise chGNRs of different chirality and size by on surface synthesis using predesigned molecular precursors. Combining scanning tunneling microscopy (STM) measurements and theory simulations, we follow the evolution of topological properties and bulk band gap depending on the width, length, and chirality of chGNRs. Our findings represent a new platform for producing topologically protected spin states and demonstrate the potential of connecting chiral edge and defect structure with band engineering., We gratefully acknowledge financial support from the Agencia Estatal de Investigación (AEI) through projects No MAT2016-78293, PID2019-107338RB, and FIS2017-83780-P, and the Maria de Maeztu Units of Excellence Programme MDM-2016-0618, from the Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2016–2019, ED431G/09), from the University of the Basque Country (Grant IT1246-19) and the Basque Departamento de Educación (PhD scholarship no. PRE_2019_2_0218 of S.S.), and from the European Regional Development Fund. We also acknowledge funding from the European Union (EU) H2020 program through the ERC (grant agreement No. 635919) and FET Open project SPRING (grant agreement No. 863098).

Platelet-rich plasma (PRP) has emerged as a viable therapeutic alternative for a number of clinical applications and has potential benefit for use in trigger finger. However, PRP use has not been previously reported for this condition. We report a 63-year-old woman sustaining a refractory trigger finger after a series of three PRP injections over a 2-week period. There was resolution of triggering, with no symptom recurrence at 3-month follow-up. On the basis of this report, we can assume that the treatment of trigger finger with PRP is a promising therapeutic option to be further explored with larger samples and high-quality studies.

Meniscal injuries are among the most frequently encountered conditions in the knee joint. Therapeutic approaches are diverse and are largely dependent on the extent and location of the injury. The purpose of this study was to describe the clinical and functional outcomes of an intraarticular and percutaneous platelet-rich plasma (PRP) injection regime in patients with stable meniscal injuries. Demographics, the type of tear, affected knee, surgical procedure, type of intervention, follow-up period, and outcomes were recorded in all cases. Patient-reported outcome measures included the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity level scale. Overall patient satisfaction, quality of life, and pain intensity were also assessed. A total of 38 cases (8 females) had sustained a stable meniscal lesion (32 medial, 6 lateral) and met the inclusion criteria. All of them received three intraarticular and percutaneous PRP injections. Patients receiving the PRP injection regime reported clinically (p = 0.000) and functionally (p = 0.000 and p = 0.001) significant improvement in all outcome measures during this interval. All patients reported they were very satisfied or satisfied with the outcome. The results of this study suggest that the treatment of stable meniscal injuries with percutaneous–intraarticular PRP injections can achieve a significant clinical and functional improvement. This research received no external funding. Partial funding for open access charge: Universidad de Málaga

Junctions composed of two crossed graphene nanoribbons (GNRs) have been theoretically proposed as electron beam splitters where incoming electron waves in one GNR can be split coherently into propagating waves in two outgoing terminals with nearly equal amplitude and zero back-scattering. Here we scrutinize this effect for devices composed of narrow zigzag GNRs taking explicitly into account the role of Coulomb repulsion that leads to spin-polarized edge states within mean-field theory. We show that the beam-splitting effect survives the opening of the well-known correlation gap and, more strikingly, that a spin-dependent scattering potential emerges which spin polarizes the transmitted electrons in the two outputs. By studying different ribbons and intersection angles we provide evidence that this is a general feature with edge-polarized nanoribbons. A near-perfect polarization can be achieved by joining several junctions in series. Our findings suggest that GNRs are interesting building blocks in spintronics and quantum technologies with applications for interferometry and entanglement., This work was financial supported by Spanish Ministerio de Ciencia e Innovación (grants No. MAT-2017-88374-P, PID2020-116093RB-C44, PID2019-103910GB-I00 and PTA2019-018134-I funded by MCIN/AEI/10.13039/501100011033/ and by “ESF investing in your future”), and the Basque Government (grants No. IT-1591-22, IT-1527-22). L. F. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme through the Marie Skłodowska-Curie Grant Agreement MagicFACE No. 797109. Computational resources were provided by DIPC. Part of the research leading to this results has been supported by the project CALIPSOplus under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020.

Transcranial direct current stimulation (tDCS) is a novel, non-invasive method of modulating brain activity by applying electrical current directly to the scalp. While the effects of tDCS are more established in the clinical setting, its influence on cognition, specifically object perception, is less clear. The goal of this systematic review was to investigate whether object perception can be improved by tDCS, and if so, under what conditions. A literature search was conducted on the following databases: PubMed, ScienceDirect, Google Scholar and PsycInfo. To be included, studies must have employed tDCS on healthy adult populations and included a measure of object perception. A total of 18 articles met inclusion criteria. The results showed that 58% of studies that applied anodal tDCS to the target region observed enhanced object perception. This was particularly the case with frontal stimulation for object detection tasks. A quantitative meta-analysis further confirmed that anodal tDCS improved object perception overall, and specifically, tDCS to frontal sites increased accuracy scores by an average of 8.8%. Although the qualitative synthesis suggested that anodal tDCS to occipital sites, such as the lateral occipital complex, may enhance object recognition, the meta-analysis showed that this effect was not significant within the occipital subgroup. This is the first systematic review and meta-analysis investigating the effects of tDCS on object perception. Although there are inconsistencies in the behavioral and tDCS methodologies employed by these studies, our analysis revealed that tDCS can enhance object perception when targeting frontal brain regions involved in top-down attention.

Triangulene nanographenes are open-shell molecules with predicted high spin state due to the frustration of their conjugated network. Their long-sought synthesis became recently possible over a metal surface. Here, we present a macrocycle formed by six [3]triangulenes, which was obtained by combining the solution synthesis of a dimethylphenyl-anthracene cyclic hexamer and the on-surface cyclodehydrogenation of this precursor over a gold substrate. The resulting triangulene nanostar exhibits a collective spin state generated by the interaction of its 12 unpaired π-electrons along the conjugated lattice, corresponding to the antiferromagnetic ordering of six S=1 sites (one per triangulene unit). Inelastic electron tunneling spectroscopy resolved three spin excitations connecting the singlet ground state with triplet states. The nanostar behaves close to predictions from the Heisenberg model of an S=1 spin ring, representing a unique system to test collective spin modes in cyclic systems., We acknowledge funding from Agencia Estatal de Investigación (PID2019-107338RB, FIS2017-83780-P, MDM-2016-0618), from the Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2019–2022, ED431G 2019/03), the Basque Government (Grant IT1255-19), the European Union H2020 program (FET Open project SPRING #863098), the European Regional Development Fund and the Basque Departamento de Educación for the PhD scholarship no. PRE_2020_2_0049 (S.S.).

Introduction There is a growing interest across scientific literature on smartphone applications (apps) aiming to modify various health behaviors. Interventions that include behavior change techniques (BCTs) have been advocated to increase their efficacy. The extent to which those techniques are present among apps is unclear. The aim of this review is to analyze the existing apps for prescribing therapeutic exercise (TE) in rehabilitating adults. Evidence acquisition The study sample was identified through systematic searches in iTunes (Apple) and Google Play (Android). Applications (apps) were assessed according to the taxonomy of BCTs for the presence/absence of these techniques. Mean and ranges were calculated for the number of observed BCTs. Number of techniques observed in free apps in both stores was calculated, but formal statistical were not conducted due to the exploratory nature of this study. Evidence synthesis Eighteen apps were identified (11 for iPhone, two for Android, and five for both). The average number of BCT included in the eligible apps was 11 (range 4 to 16), with predominance of four techniques: "request the establishment of behavior" (100% of the apps), "providing instructions" (100%), "requesting an implementation" (100%), and "determine graded tasks" (100%). Techniques such as "taking a behavioral contract," "stress management," "prevention of relapse," and "promote the identification of barriers" were not used in the apps reviewed. Conclusions Our work demonstrates that apps prescribing TE among rehabilitating adults applied an average of 11 BCTs. Presence of BCTs varied by app type. No difference in the number of BCTs identified between iOS and Android apps was found.

We analyze theoretically four-terminal electronic devices composed of two crossed graphene nanoribbons (GNRs) and show that they can function as beam splitters or mirrors. These features are identified for electrons in the low-energy region where a single valence or conduction band is present. Our modeling is based on p z orbital tight binding with Slater-Koster-type matrix elements fitted to accurately reproduce the low-energy bands from density functional theory calculations. We analyze systematically all devices that can be constructed with either zigzag or armchair GNRs in AA and AB stackings. From Green's function theory the elastic electron transport properties are quantified as a function of the ribbon width. We find that devices composed of relatively narrow zigzag GNRs and AA-stacked armchair GNRs are the most interesting candidates to realize electron beam splitters with a close to 50:50 ratio in the two outgoing terminals. Structures with wider ribbons instead provide electron mirrors, where the electron wave is mostly transferred into the outgoing terminal of the other ribbon, or electron filters where the scattering depends sensitively on the wavelength of the propagating electron. We also test the robustness of these transport properties against variations in the intersection angle, stacking pattern, lattice deformation (uniaxial strain), inter-GNR separation, and electrostatic potential differences between the layers. These generic features show that GNRs are interesting basic components to construct electronic quantum optical setups., This work was supported by the project Spanish Ministerio de Economía y Competitividad (MINECO) through the Grants no. FIS2017-83780-P (Graphene Nanostructures “GRANAS”) and no.MAT2016-78293-C6-4R, the Basque Departamento de Educación through the PhD fellowship no. PRE_2019_2_0218 (S.S.), the University of the Basque Country through the Grant no. IT1246-19, and the European Union (EU) through Horizon 2020 (FET-Open project SPRING Grant no. 863098).

Graphene can develop large magnetic moments in custom crafted open-shell nanostructures such as triangulene, a triangular piece of graphene with zigzag edges. Current methods of engineering graphene nano-systems on surfaces succeeded in producing atomically precise open-shell structures, but demonstration of their net spin remains elusive to date. Here, we fabricate triangulene-like graphene systems and demonstrate that they possess a spin $S=1$ ground state. Scanning tunnelling spectroscopy identifies the fingerprint of an underscreened $S=1$ Kondo state on \rev{these} flakes at low temperatures, signaling the dominant ferromagnetic interactions between two spins. Combined with simulations based on the meanfield Hubbard model, we show that this $S=1$ $\pi$-paramagnetism is robust, and can be manipulated to a $S=1/2$ state by adding additional H-atoms to the radical sites. \rev{Our results demonstrate that $\pi$-paramagnetism of high-spin graphene flakes can survive on surfaces, opening the door to study the quantum behaviour of interacting $\pi$-spins in graphene systems., Comment: 4 figures plus supporting information, APS copyright

Thumb carpometacarpal osteoarthritis (TCMC-OA) is a progressively disabling, debilitating condition presenting with thumb base pain and hand functional impairment. Platelet-rich plasma has been used widely for the management of musculoskeletal pathologies, OA being among them. To our knowledge, only a few cases have been previously reported on this topic until now. A 59-year-old male professional pianist presented with chronic, mild onset of right thumb base pain involving a progressive lack of pinch strength in his right hand, and severe difficulties with playing. Three PRP injections were administered to the TCMC joint on a 1-week interval regime. Clinical outcomes were assessed by using the visual analog scale (VAS) for pain, grip and pinch strength, and the Quick-DASH Questionnaire. Functional outcome was excellent according to patient’s capability with daily living activities and specific playing demands. At 12 months follow-up, no recurrences or complications were identified, with the musician returning to his previous level of performance 2 weeks before the end of this period. Patient self-reported satisfaction was high and he reported to return to his routine piano activity with no limitations. This case-based review study documents the clinical efficacy of PRP treatment from both functional and perceived-pain perspectives in a professional pianist. Presenting this case, our aim is to draw attention of healthcare providers dealing with TCMC-OA to PRP as a safe, beneficial therapy for this condition which needs further assessment in randomized controlled trials.

Turning graphene magnetic is a promising challenge to make it an active material for spintronics. Predictions state that graphene structures with specific shapes can spontaneously develop magnetism driven by Coulomb repulsion of π-electrons, but its experimental verification is demanding. Here, we report on the observation and manipulation of individual magnetic moments in graphene open-shell nanostructures on a gold surface. Using scanning tunneling spectroscopy, we detect the presence of single electron spins localized around certain zigzag sites of the carbon backbone via the Kondo effect. We find near-by spins coupled into a singlet ground state and quantify their exchange interaction via singlet-triplet inelastic electron excitations. Theoretical simulations picture how electron correlations result in spin-polarized radical states with the experimentally observed spatial distributions. Extra hydrogen atoms bound to radical sites quench their magnetic moment and switch the spin of the nanostructure in half-integer amounts. Our work demonstrates the intrinsic π-paramagnetism of graphene nanostructures., π-magnetism in graphene systems has been predicted but remains an experimental challenge. Here the authors report the discovery of unpaired electron spins localized in certain sites of graphene nanoribbons, and the measurement of their coupling by inducing singlet-triplet excitations with a scanning tunneling microscope.

Objective: Cold therapy has been pointed out as beneficial treatment for acute injuries. Stretching exercises have been widely used during last decades for prevention and recovery purposes. Functional performance tests have evolved in a mode of determining an athlete´s functional ability. The purpose of this study was to assess the influence of ice immersion and a guided-stretching exercises protocol to the lower extremity on functional performance in a student, female population. Methods: Twenty-five female physical activity students volunteered to participate in this study. We used a pretestpostest design with an untreated control group. Before and immediately following the treatment, subjects performed these functional performance tests: the squat jump (SJ), the counter-movement jump (CMJ), 30-m sprint, and 1000- m run. Subjects were randomly assigned to either a control group (n=9) or 2 experimental groups: ice immersion/no stretching (n=8); no ice immersion/stretching (n=8). The experiment was repeated two hours later the same day and two days later. The postest procedures were performed as previously described. The average of the two test trials for jumping functional performance tests was used for comparison. Results: Results showed no significant differences among these routines on functional performance scores. ANOVA analysis revealed no significant differences among these routines on functional performance scores. The 30-m sprint (p

Turning graphene magnetic is a promising challenge to make it an active material for spintronics. Predictions state that graphene structures with specific shapes can spontaneously develop magnetism driven by Coulomb repulsion of π-electrons, but its experimental verification is demanding. Here, we report on the observation and manipulation of individual magnetic moments in graphene open-shell nanostructures on a gold surface. Using scanning tunneling spectroscopy, we detect the presence of single electron spins localized around certain zigzag sites of the carbon backbone via the Kondo effect. We find near-by spins coupled into a singlet ground state and quantify their exchange interaction via singlet-triplet inelastic electron excitations. Theoretical simulations picture how electron correlations result in spin-polarized radical states with the experimentally observed spatial distributions. Extra hydrogen atoms bound to radical sites quench their magnetic moment and switch the spin of the nanostructure in half-integer amounts. Our work demonstrates the intrinsic π-paramagnetism of graphene nanostructures.