Search

Magnetic impurities create in-gap states on superconductors. Recent experiments explore the topological properties of one-dimensional arrays of magnetic impurities on superconductors, because in certain regimes p-wave pairing can be locally induced leading to new topological phases. A byproduct of the new accessible phases is the appearance of zero-energy edge states that have non-Abelian exchange properties and can be used for topological quantum computation. Despite the large amount of theory devoted to these systems, most treatments use approximations that render their applicability limited when comparing with usual experiments of 1D impurity arrays on wide-band superconductors. These approximations either involve tight-binding-like approximations where the impurity energy scales match the minute energy scale of the superconducting gap and are many times unrealistic, or they assume strongly-bound in-gap states. Here, we use a theory for s-wave superconductors based on a wide-band normal metal, with any possible energy scale for the magnetic impurities and develop an efficient way of computing the well-known topological invariants of infinite chains. We perform concrete calculations on ferromagnetic spin chains using BCS Green's function for the superconductor and including Rashba coupling to compare with recent experimental results. The infinite-chain properties can be analytically obtained, giving us a way to compare with finite-chain calculations. We show that it is possible to converge to the infinite limit by doing finite-size numerical calculation, paving the way for numerical calculations not based on analytical Green's functions. As an application, we show that energy oscillations around zero with increasing number of atoms in the spin chain does not reflect the topological origin of the low-energy state., Financial support from the Spanish MICINN (Projects RTI2018-097895-B-C44 and Excelencia EUR2020-112116) and Eusko Jaurlaritza (Project PIBA_2020_1_0017) is gratefully acknowledged.

Electronic states in the gap of a superconductor inherit intriguing many-body properties from the superconductor. Here, we create these in-gap states by manipulating Cr atomic chains on the $\ensuremath{\beta}\ensuremath{-}\mathrm{Bi}{}_{2}\mathrm{Pd}$ superconductor. We find that the topological properties of the in-gap states can greatly vary depending on the crafted spin chain. These systems make an ideal platform for nontrivial topological phases because of the large atom-superconductor interactions and the existence of a large Rashba coupling at the Bi-terminated surface. We study two spin chains, one with atoms two lattice parameters apart and one with $\sqrt{2}$ lattice parameters. Of these, only the second one is in a topologically nontrivial phase, in agreement with the spin interactions for this geometry.

SUMMARY: Variation in the biceps brachii muscle is extremely frequent and has a clinical significance. During an educational dissection, third head of the biceps brachii muscle was found on the left side in a Korean cadaver. The short and long heads showed normal morphology and course: however, additional head originated from the greater tubercle connected to long head of biceps brachii muscle and crossed the musculocutaneous nerve perpendicularly. And then, it was inserted into short head of the biceps brachii muscle. The author describes this previously novel case report and discusses the clinical implications of such a variant.

Combining the complex ordering ability of molecules with their local magnetic properties is a little-explored technique to tailor spin structures on surfaces. However, revealing the molecular geometry can be demanding. Nickelocene (Nc) molecules present a large spin-flip excitation leading to clear changes of conductance at the excitation-threshold bias. Using a superconducting tip, we have the energy resolution to detect small shifts of the Nc spin-flip excitation thresholds, permitting us to reveal the different individual environments of Nc molecules in an ordered layer. This knowledge allows us to reveal the adsorption configuration of a complex molecular structure formed by Nc molecules in different orientations and positions. As a consequence, we infer that Nc layers present a strong noncollinear magnetic-moment arrangement., Financial support from the Spanish MICINN (project RTI2018-097895-B-C44), the European H2020 FET open project MeMo (grant no. 766864), and the French Agence Nationale de la Recherche (grants no. ANR-13-BS10-0016, ANR-11-LABX-0058 NIE and ANR-10-LABX-0026 CSC) is gratefully acknowledged.

We investigated spin-1/2 hydrogenated titanium (Ti) atoms on MgO using scanning tunneling microscopy (STM) combined with electron spin resonance (ESR) in vector magnetic fields. Rotating external magnetic fields, we observed rather drastic changes in both amplitude and frequency of resonance signals for single Ti atoms. While the variation of ESR amplitudes reflects the effects of the spin polarization of a magnetic tip and local magnetic fields created by the interaction between the tip and Ti, the change of resonance frequencies shows the anisotropy of g values for Ti atoms. Using the Ti atoms at the low-symmetry bridge adsorption site of the MgO lattice allowed for identifying the g values in all three spatial directions. Multiplet calculations confirmed the origin of this anisotropy as the spin-orbit coupling induced effects of crystal. Our results show the capability of single atomic spins as a sensor to probe magnetic surroundings and highlight the precision of ESR-STM to identify the single atom's spin states in a solid-state environment., This work was supported by the Institute for Basic Science (Grant No. IBS-R027-D1). D.-J.C. acknowledges financial support from the Spanish MICINN (Project No. RTI2018- 097895-B-C44 and Excelencia Project No. EUR2020-112116) and Eusko Jaurlaritza (Project No. PIBA_2020_-1_0017). F.D. acknowledges financial support from Spanish MICINN (Grant No. PID2019-109539GB-C41), Basque Government (Grant No. IT986-16), and Canary Islands program Viera y Clavijo (Grant No. 2017/0000231). C.P.L. acknowledges financial support from the ONR.

The electrical control and readout of molecular spin states are key for high-density storage. Expectations are that electrically-driven spin and vibrational excitations in a molecule should give rise to new conductance features in the presence of magnetic anisotropy, offering alternative routes to study and, ultimately, manipulate molecular magnetism. Here, we use inelastic electron tunneling spectroscopy to promote and detect the excited spin states of a prototypical molecule with magnetic anisotropy. We demonstrate the existence of a vibron-assisted spin excitation that can exceed in energy and in amplitude a simple excitation among spin states. This excitation, which can be quenched by structural changes in the magnetic molecule, is explained using first-principles calculations that include dynamical electronic correlations., This work was supported by the Agence Nationale de la Recherche (grants No. ANR-13-BS10-0016, ANR-11-LABX-0058 NIE and ANR-10-LABX-0026 CSC) and by the Agencia Española de Investigación (grants Nos. MAT2016-78293-C6-1-R and MDM-2016-0618). D.-J.C. and N.L. thank the MICINN (project RTI2018-097895-B-C44). M.-L.B. thanks the national computational center CINES and TGCC (GENCI project: A0030807364).

Eigenstate multifractality is a distinctive feature of noninteracting disordered metals close to a metal-insulator transition, whose properties are expected to extend to superconductivity. While multifractality in three dimensions (3D) only develops near the critical point for specific strong-disorder strengths, multifractality in 2D systems is expected to be observable even for weak disorder. Here we provide evidence for multifractal features in the superconducting state of an intrinsic, weakly disordered single-layer NbSe2 by means of low-temperature scanning tunneling microscopy/spectroscopy. The superconducting gap, characterized by its width, depth, and coherence peaks' amplitude, shows a characteristic spatial modulation coincident with the periodicity of the quasiparticle interference pattern. The strong spatial inhomogeneity of the superconducting gap width, proportional to the local order parameter in the weak-disorder regime, follows a log-normal statistical distribution as well as a power-law decay of the two-point correlation function, in agreement with our theoretical model. Furthermore, the experimental singularity spectrum f(α) shows anomalous scaling behavior typical from 2D weakly disordered systems., We acknowledge financial support from AEI/FEDER-EU through the Maria de Maeztu unit of excellence MDM-2016-0618. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under Contract No. DE-AC02-05CH11231. A.M.G.-G. acknowledges additional support from a Shanghai talent program and from the National Natural Science Foundation of China (NSFC) (Grant number 11874259).

Mutations in the promoter region of telomerase reverse transcriptase (TERT) and alterations in telomere length (TL) have been the focus of research in various types of cancer. In the present study, the frequency and clinical characteristics of TERT promoter mutations and TL were studied in non-small cell lung cancers (NSCLC). TERT promoter mutations and TL were analyzed in 188 patients using DNA sequencing and the reverse transcription-quantitative polymerase chain reaction, respectively. The TERT promoter mutation rate was observed to be 2.2% (4/188 NSCLC cases), and it was significantly associated with regional lymph node invasion (P

PURPOSE The retention and capture functions of hand can be achieved by the consistent manner work of the extensor and flexor muscles. Therefore, it is important to know variations of the extensor and flexor muscles. METHODS During an educational dissection, accessory heads of the extensor carpi radialis longus muscle were found on the right side in a Korean cadaver. RESULTS The extensor carpi radialis longus muscle was originated from the lateral supracondylar ridge of the humerus and trifurcated into three heads as lateral, intermediated, and medial heads. The lateral and intermediated heads merged and inserted to the base of the second metacarpal bone. However, medial head of extensor carpi radialis longus muscle was merged with the extensor carpi radialis brevis muscle. CONCLUSIONS Knowledge of the variations of the ECRL is important for surgeons because the presence of the ECRL variations increases the incidence of iatrogenic injuries during surgery and invasive procedures.

Bulk and single-layer 2H-NbSe2 exhibit identical charge density wave order (CDW) with a quasi-commensurate 3 × 3 superlattice periodicity. Here we combine scanning tunnelling microscopy (STM) imaging at T = 1 K of 2H-NbSe2 with first-principles density functional theory (DFT) calculations to investigate the structural atomic rearrangement of this CDW phase. Our calculations for single-layers reveal that six different atomic structures are compatible with the 3 × 3 CDW distortion, although all of them lie on a very narrow energy range of at most 3 meV per formula unit, suggesting the coexistence of such structures. Our atomically resolved STM images of bulk 2H-NbSe2 unambiguously confirm this by identifying two of these structures. Remarkably, these structures differ from the X-ray crystal structure reported for the bulk 3 × 3 CDW which in fact is also one of the six DFT structures located for the single-layer. Our calculations also show that due to the minute energy difference between the different phases, the ground state of the 3 × 3 CDW could be extremely sensitive to doping, external strain or internal pressure within the crystal. The presence of multiphase CDW order in 2H-NbSe2 may provide further understanding of its low temperature state and the competition between different instabilities., Work at Bellaterra was supported by Spanish MINECO (Grants FIS2015-64886-C5-3-P and FIS2015-64886-C5-4-P, and the Severo Ochoa Centers of Excellence Program under Grants SEV-2017-0706 and SEV-2015-0496), Generalitat de Catalunya (Grant 2017SGR1506 and the CERCA Program) and by the European Union MaX Center of Excellence (Grant 824143). The work by B.G. has been performed in the context of the Physics Ph.D. program of the Universitat Autònoma de Barcelona. M.M.U acknowledges support by the Spanish MINECO under grant no. MAT2017-82074-ERC and by the ERC Starting grant “LINKSPM” (Grant 758558).

Bulk and single-layer 2 H-NbSe

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.

Magnetism at low dimensions is a thriving field of research with exciting opportunities in technology. This Colloquium focuses on the properties of 1D magnetic systems on solid surfaces. From the emulation of 1D quantum phases to the potential realization of Majorana edge states, spin chains are unique systems to study. The advent of scanning tunneling microscope (STM) based techniques has permitted us to engineer spin chains in an atom-by-atom fashion via atom manipulation and to access their spin states on the ultimate atomic scale. Here the current state of research on spin correlations and dynamics of atomic spin chains as studied by the STM is presented. After a brief review of the main properties of spin chains on solid surfaces, spin chains are classified according to the coupling of their magnetic moments with the holding substrate. This classification scheme takes into account that the nature and lifetimes of the spin-chain excitations intrinsically depend on the holding substrate. Interest is shown of using insulating layers on metals, which generally results in an increase in the spin state’s lifetimes such that their quantized nature gets evident and they are individually accessible. Next shown is the use of semiconductor substrates promising additional control through the tunable electron density via doping. When the coupling to the substrate is increased for spin chains on metals, the substrate conduction electron mediated interactions can lead to emergent exotic phases of the coupled spin chain-substrate conduction electron system. A particularly interesting example is furnished by superconductors. Magnetic impurities induce states in the superconducting gap. Because of the extended nature of the spin chain, the in-gap states develop into bands that can lead to the emergence of 1D topological superconductivity and consequently to the appearance of Majorana edge states. Finally, an outlook is given on the use of spin chains in spintronics, quantum communication, quantum computing, quantum simulations, and quantum sensors, D.-J. C. and N. L. acknowledge financial support from MICINN (RTI2018-097895-B-C44) and FEDER funds. J. W. and K. v. B. received funding from the Deutsche Forschungsgemeinschaft (DFG, German Research foundation)—SFB668. A. F. O. acknowledges support from the Netherlands Organisation for Scientific Research (NWO) and the European Research Council (ERC Starting Grant No. 676895 “SPINCAD”). A. J. H acknowledges support from the Institute for Basic Science under IBS-R027-D1

Variations in the upper limbs are common and are the main causes for iatrogenic injury during invasive procedures. A rare division of the axillary artery was found on the left side of a Korean cadaver during an educational dissection. The subscapular artery originated from the second part of the axillary artery. And then it gave off an aberrant branch to the pectoralis major muscle, as pectoral branch. The author describes this previously unreported case and discusses its prevalence and the clinical implications.

We thank Javier Zaldivar and Joeri de Bruijckere for developing the deconvolution process and Sebastian Bergeret for discussions. D.-J. C. and J. I. P. thank the European Union for support under the H2020-MSCA-IF-2014 Marie-Curie Individual Fellowship program (Proposal No. 654469), Spanish MINECO (MAT2016-78293-C6-1-R), Diputacion Foral de Gipuzkoa for Grant No. 64/15, and the European Regional Development Fund (ERDF). N. L. thanks Spanish MINECO (Grant No. MAT2015-66888-C3-2-R). M. M. U. acknowledges Spanish MINECO (MAT2014-60996-R). E. H., I. G., and H. S. acknowledge FIS2014-54498-R and MDM-2014-0377, COST MP16218 nanocohybri, ERC PNICTEYES Grant Agreement No. 679080, and Departamento Administrativo de Ciencia, Tecnologia e Innovacion, COLCIENCIAS (Colombia), Programa doctorados en el exterior and convocatoria 568-2012, as well as Comunidad de Madrid through program Nanofrontmag-CM (Grant No. S2013/MIT-2850)

Alterations in mitochondrial DNA (mtDNA) have been studied in various cancers. However, the clinical value of mtDNA copy number (mtCN) alterations in gastric cancer (GC) is poorly understood. In the present study, we investigated whether alterations in mtCNs might be associated with clinicopathological parameters in GC cases. mtCN was measured in 109 patients with GC by real-time PCR. Then, correlations with clinicopathological characteristics were analyzed. mtCN was elevated in 64.2% of GC tissues compared with paired, adjacent, non- cancerous tissue. However, the observed alterations in mtCN were not associated with any clinicopathological characteristics, including age, gender, TN stage, Lauren classification, lymph node metastasis, and depth of invasion. Moreover, Kaplan-Meier survival curves revealed that mtCN was not significantly associated with the survival of GC patients. In this study, we demonstrated that mtCN was not a significant marker for predicting clinical characteristics or prognosis in GC.

Colorectal cancer is a heterogeneous disorder than arises via multiple distinct pathways, from tubular adenomas (TAs) and sessile serrated adenomas (SSAs), which are clinically, morphologically, and molecularly different. We examined PIK3CA amplification in colorectal precancerous legions, including TAs and SSAs. DNA was isolated from paired normal and tumoral tissues in 64 TAs and 32 SSAs. PIK3CA amplification, KRAS mutation, and BRAF mutation were analyzed by real-time PCR and pyrosequencing. PIK3CA amplification was found in 25% of TAs and 9.4% of SSAs, respectively. KRAS and BRAF mutations were mutually exclusive in both TAs and SSAs. In TAs, PIK3CA amplification was associated with left side and it was mutually exclusive with KRAS mutation. These results suggest that PIK3CA amplification may be early and important event in colorectal carcinogenesis and may drive the development of left-side TAs independently with KRAS mutation.

Mixing of discretized states in quantum magnets has a radical impact on their properties. Managing this effect is key for spintronics in the quantum limit. Magnetic fields can modify state mixing and, for example, mitigate destabilizing effects in single-molecule magnets. The exchange bias field has been proposed as a mechanism for localized control of individual nanomagnets. Here, we demonstrate that exchange coupling with the magnetic tip of a scanning tunnelling microscope provides continuous tuning of spin state mixing in an individual nanomagnet. By directly measuring spin relaxation time with electronic pump-probe spectroscopy, we find that the exchange interaction acts analogously to a local magnetic field that can be applied to a specific atom. It can be tuned in strength by up to several tesla and cancel external magnetic fields, thereby demonstrating the feasibility of complete control over individual quantum magnets with atomically localized exchange coupling.

We show that the magnetic ordering of coupled atomic dimers on a superconductor is revealed by their intragap spectral features. Chromium atoms on the superconductor β-Bi_{2}Pd surface display Yu-Shiba-Rusinov bound states, detected as pairs of intragap excitations in tunneling spectra. By means of atomic manipulation with a scanning tunneling microscope's tip, we form Cr dimers with different arrangements and find that their intragap features appear either shifted or split with respect to single atoms. These spectral variations are associated with the magnetic coupling, ferromagnetic or antiferromagnetic, of the dimer, as confirmed by density functional theory simulations. The striking qualitative differences between the observed tunneling spectra prove that intragap Shiba states are extremely sensitive to the magnetic ordering on the atomic scale.

Positive association between telomere length and mitochondrial DNA (mtDNA) copy number were introduced in healthy and patients with psychiatric disorder. Based on frequent genetic changes of telomere and mitochondria in colorectal carcinomas (CRC), we studied their clinical characteristics and their association in colorectal carcinogenesis. DNA was extracted from 109 CRCs, 64 colorectal tubular adenomas (TAs), and 28 serrated polyps (SPs), and then, telomere length and mtDNA copy number were analyzed in these legions by using a real-time PCR assay. Telomere length and mtDNA copy number (mean ± S.D) in CRCs was 1.87 ± 1.52 and 1.61 ± 1.37, respectively. In TAs and SPs, relative mtDNA copy number was 0.92 ± 0.71 and 1.84 ± 1.06, respectively, shoing statistical difference (p = 0.017). However, telomere length was similar in these precancerous legions. Telomere length and mtDNA copy number did not show clinical and prognostic values in CRCs, however, positive correlation between telomere length and mitochondrial DNA copy number were found in CRC (r = 0.408, p

The creation of molecule-like structures in which magnetic atoms interact controllably is full of potential for the study of complex or strongly correlated systems. Here, we create spin chains in which a strongly correlated Kondo state emerges from magnetic coupling of transition-metal atoms. We build chains up to ten atoms in length by placing Fe and Mn atoms on a CuN surface with a scanning tunneling microscope. The atoms couple antiferromagnetically via superexchange interaction through the nitrogen atom network of the surface. The emergent Kondo resonance is spatially distributed along the chain. Its strength can be controlled by mixing atoms of different transition metal elements and manipulating their spatial distribution. We show that the Kondo screening of the full chain by the electrons of the nonmagnetic substrate depends on the interatomic entanglement of the spins in the chain, demonstrating the prerequisites to build and probe spatially extended strongly correlated nanostructures., D.J.C. and J.A.J.B. acknowledge postdoctoral fellowship from the Alexander von Humboldt foundation. M.T. acknowledges support from the DFG-SFB 767. J.A.J.B. acknowledges support from the Natural Sciences and Engineering Research Council of Canada. N.L. and R.R. acknowledge support form Spanish MINECO (grant no. MAT2012-38318-C03-02 with joint financing by FEDER Funds from the European Union). ICN2 acknowledges support from the Severo Ochoa Program (MINECO, grant SEV-2013-0295).

Scattering of electrons by localized spins is the ultimate process enabling detection and control of the magnetic state of a spin-doped material. At the molecular scale, scattering is mediated by the orbitals hosting the spin. Here we report the selective excitation of a molecular spin by tunneling through different molecular orbitals. Spatially resolved tunneling spectra on iron-porphyrins reveal that the inelastic spin excitation extends beyond the iron site, changing shape and symmetry along the molecule. Combining density functional theory simulations with a phenomenological scattering model, we show that the extension and lineshape of the inelastic signal are due to excitation pathways assisted by different frontier orbitals. By selecting the intramolecular site for electron injection, the relative weight of iron and pyrrole orbitals in the tunneling process is modified. Thus, the excitation mechanism, reflected by its spectral lineshape, depends on the degree of localization and energy alignment of the chosen molecular orbital., This work has been funded by the COST 15128 Molecular Spintronics project, by Marie Curie IF ARTE, by the Spanish Ministerio de Economía y Competitividad (MINECO) through the cooperative grant No. MAT2016-78293 and grant No. FIS2016-75862-P, and by the Basque Government (Dep. Industry, Grant PI-2015-1-42, Dep. Education, Grant PI-2016-1-27 and Grant IT-756-13), the EU project PAMS (610446), and the European Regional Development Fund (ERDF).

Aims and background The incidence rate of colorectal cancer (CRC) increases every year in Korean populations. However, association between the GNAS mutation and colorectal precancerous lesions has not been studied in in Korean populations. To contribute to better understanding of colorectal carcinogenesis, we analyzed GNAS mutation in 100 cancerous and 96 precancerous colorectal lesions. Methods The records of colonoscopic polypectomy performed at Dongsan Medical Center between 1999 and 2003 were reviewed retrospectively. Precancerous lesions included 7 villous adenomas, 59 tubular adenomas, and 18 sessile serrated adenomas, and 12 hyperplastic polyps. Keimyung Human Bio-Resource Bank at Dongsan Medical Center provided 100 CRC samples. Results GNAS mutation was not found in any colorectal cancer or any precancerous colorectal lesions, including villous adenoma, which is thought to harbor the mutation. Conclusions The role of GNAS mutation might be limited in colorectal neoplasms of the Korean population.

The purpose of this case report is to report vascular variations in the abdomen because of its clinical importance for the surgeries like acute abdominal emergencies and symptomatic aneurysms. Here, we report an extremely rare case with an ileocolic vein passing through the annulus of the ileocolic artery.During the routine dissection, we found an ileocolic vein perforating through a ring-shaped ileocolic artery.A ring-shaped ileocolic artery was originating from the superior mesenteric artery as a single branch. After forming the circle, it maintained the regular branching patterns. The ileocolic vein was drained from the ascending colon, cecum, appendix and the distal part of the ileum and passed the center of the ring-shaped part of the ileocolic artery from posterior to anterior. Other structures of the abdomen were normal.We reported this rare variation and suggest that the clinicians should be aware of this variation for succeeding surgery and making a good diagnosis for the patients.

A low-temperature scanning tunneling microscope was employed to study the differential conductance in an atomic junction formed by an adsorbed Co atom on a Cu(100) surface and a copper-covered tip. A zero-bias anomaly (ZBA) reveals spin scattering off the Co atom, which is assigned to a Kondo effect. The ZBA exhibits a characteristic asymmetric lineshape when electrons tunnel between tip and sample, while upon the tip-Co contact it symmetrizes and broadens. Through density functional theory calculations and the non-equilibrium non-crossing approximation, we show that the lineshape broadening is mainly a consequence of the additional coupling to the tip, while non-equilibrium effects only modify the large-bias tails of the ZBA., D.J.C. acknowledges the European Union for support under H2020-MSCA-IF-2014 Marie-Curie Individual Fellowship programme Proposal No. 654469. P.A. acknowledges the CCT-Rosario Computational Center. Financial support from CONICET, the Agence Nationale de la Recherche (Grant Nos. ANR-13-BS10-0016, ANR-11-LABX-0058 NIE, and ANR-10-LABX-0026 CSC), and MINECO (Grant No. MAT2015-66888-C3-2-R) is gratefully acknowledged.

The Kondo effect of a Co atom on Cu(100) was investigated with a low-temperature scanning tunneling microscope using a monoatomically sharp nickel tip. Upon a tip-Co contact, the differential conductance spectra exhibit a spin-split asymmetric Kondo resonance. The computed ab initio value of the exchange coupling is too small to suppress the Kondo effect, but sufficiently large to produce the splitting observed. A quantitative analysis of the line shape using the numerical renormalization group technique indicates that the junction spin polarization is weak., 5 pages, 4 figures

Heterogeneous atomic magnetic chains are built by atom manipulation on a ${\mathrm{Cu}}_{2}\mathrm{N}/\mathrm{Cu}$ (100) substrate. Their magnetic properties are studied and rationalized by a combined scanning tunneling microscopy (STM) and density functional theory (DFT) work completed by model Hamiltonian studies. The chains are built using Fe and Mn atoms ontop of the Cu atoms along the N rows of the ${\mathrm{Cu}}_{2}\mathrm{N}$ surface. Here, we present results for ${\mathrm{FeMn}}_{x}$ chains $(x=1--6)$ emphasizing the evolution of the geometrical, electronic, and magnetic properties with chain size. By fitting our results to a Heisenberg Hamiltonian we have studied the exchange-coupling matrix elements $J$ for different chains. For the shorter chains, $x\ensuremath{\le}2$, we have included spin-orbit effects in the DFT calculations, extracting the magnetic anisotropy energy. Our results are also fitted to a simple anisotropic spin Hamiltonian and we have extracted values for the longitudinal-anisotropy $D$ and transversal-anisotropy $E$ constants. These parameters together with the values for $J$ allow us to compute the magnetic excitation energies of the system and to compare them with the experimental data.

Gantzer’s muscle (GM) is an additional muscle in the forearm, which develops as an accessory head of the flexor pollicis longus or the flexor digitorum profundus. The study aimed to determine the topography of the GM and to define the topographical relationship between the GM and the neurovascular structures surrounding it. After confirming the presence of GM, its topography and the neurovascular structures were analyzed to determine the correlation between them in 73 upper limbs. The incidence of GM was 47.95% (35/73) and the average insertion point of GM was identified at 49.33 ± 7.47‰ (119.82 ± 20.80 mm) on the reference line between the medial epicondyle and the pisiform bone. And the branching points of the median nerve and the ulnar artery were located 19.91 ± 11.23‰ (52.21 ± 24.67 mm), 17.45 ± 8.39‰ (42.53 ± 20.54 mm) on the reference line, respectively. The presence of GM had no significant correlation with the position of the nerve branches. On the other hand, the branching point of the ulnar artery was distally located in the cases with the presence of the GM (17.35 ± 8.65 vs 19.42 ± 10.87, p = 0.031). There was a significant positive correlation between the point of arterial bifurcation and the length of the GM (r = 0.407, p = 0.015). This study suggested that the GM has a topographical relation with the arterial structures, perhaps for embryological reasons.