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We report the detailed analysis of temperature dependent neutron diffraction pattern of the Cr$_2$CoAl inverse Heusler alloy and unveil the magnetic structure up to the phase transition as well as its fully compensated ferrimagnetic nature. The Rietveld refinement of the diffraction pattern using the space group I$\bar4${\it m}2 confirm the inverse tetragonal structure over the large temperature range from 100~K to 900~K. The refinement of the magnetic phase considering the wave vector $k=$ (0, 0, 0) reveals the ferrimagnetic nature of the sample below 730$\pm$5~K. This transition temperature is obtained from empirical power law fitting of the variation in the ordered net magnetic moment and intensity of (110) peak as a function of temperature. The spin configuration of the microscopic magnetic structure suggests the nearly fully compensated ferrimagnetic behavior where the magnetic moments of Cr2 are antiparallel with respect to the Cr1, and Co moments. Moreover, the observed anomaly in the thermal expansion and lattice parameters at 730$\pm$5~K suggest that the distortion in crystal structure may play an important role in the magnetic phase transition., Comment: submitted

We investigate the electronic and magnetic properties as well as lattice dynamics and spin-phonon coupling of $\beta$-Na$_{0.33}$V$_2$O$_5$ using temperature-dependent Raman scattering, dc-magnetization and dc-resistivity, x-ray photoemission, and absorption spectroscopy. The Rietveld refinement of XRD pattern with space group C2/m confirms the monoclinic structure. The analysis of temperature-dependent Raman spectra in a temperature range of 13--673~K reveals an anharmonic dependence of the phonon frequency and full width at half maximum, which is accredited to the symmetric phonon decay. However, below about 40 K, the hardening of the phonon frequency beyond anharmonicity is attributed to the spin-phonon coupling. Interestingly, the estimated effective magnetic moment $\mu_{\rm eff}=$ 0.63~$\mu_B$ from the magnetization data manifests a mixed-valence state of V ions in 4+ (18$\pm$1\%) and 5+ (82$\pm$1\%). A similar ratio of V$^{4+}$ to V$^{5+}$ is also observed in the x-ray photoemission and x-ray absorption near-edge spectra and that is found to be consistent with the sample stoichiometry. In addition, the V$^{4+}$ ions are distributed between different vanadium (V1 and V3) sites. The analysis of extended x-ray absorption fine structure at different V-sites gives the corresponding V--O bond lengths, which are utilized in the assignment of Raman modes. Moreover, the temperature-dependent resistivity resembles a semiconducting behavior where the charge carrier transport is facilitated by the band conduction at higher temperatures and via hopping $\le$260~K., Comment: to be published in PRB

We investigate the electronic and magnetic properties as well as lattice dynamics and spin-phonon coupling of $β$-Na$_{0.33}$V$_2$O$_5$ using temperature-dependent Raman scattering, dc-magnetization and dc-resistivity, x-ray photoemission, and absorption spectroscopy. The Rietveld refinement of XRD pattern with space group C2/m confirms the monoclinic structure. The analysis of temperature-dependent Raman spectra in a temperature range of 13--673~K reveals an anharmonic dependence of the phonon frequency and full width at half maximum, which is accredited to the symmetric phonon decay. However, below about 40 K, the hardening of the phonon frequency beyond anharmonicity is attributed to the spin-phonon coupling. Interestingly, the estimated effective magnetic moment $μ_{\rm eff}=$ 0.63~$μ_B$ from the magnetization data manifests a mixed-valence state of V ions in 4+ (18$\pm$1\%) and 5+ (82$\pm$1\%). A similar ratio of V$^{4+}$ to V$^{5+}$ is also observed in the x-ray photoemission and x-ray absorption near-edge spectra and that is found to be consistent with the sample stoichiometry. In addition, the V$^{4+}$ ions are distributed between different vanadium (V1 and V3) sites. The analysis of extended x-ray absorption fine structure at different V-sites gives the corresponding V--O bond lengths, which are utilized in the assignment of Raman modes. Moreover, the temperature-dependent resistivity resembles a semiconducting behavior where the charge carrier transport is facilitated by the band conduction at higher temperatures and via hopping $\le$260~K., to be published in PRB

Crystal-field excitations in transition-metal oxides where -rare-earth elements locate in the space between the transition-metal-oxide tetrahedra and octahedra, are assumed to be robust with respect to external perturbations such as temperature. Using inelastic neutron-scattering experiments, a giant shift of the energy of the lowest crystal-field excitation of Er$^{3+}$ ($^{4}$I$_{15/2}$) in ErFeO$_3$ from 0.35 meV to 0.75 meV was observed on cooling from 10K to 1.5K through the magnetic ordering temperature of Er$^{3+}$ at 4.1 K. A crystal-field model was proposed to explain the observed crystal field excitations in this work. The model indicates the lowest-energy crystal-field excitation in ErFeO$_3$ is the first Kramers doublet above the ground state. Its energy substantially shifts by the internal field induced by the ordered Er$^{3+}$ magnetic moments. Further magnetic-field-dependent measurements provide strong supportive evidence for this scenario. By fitting the external magnetic-field dependency of the crystal-field excitation energy, the internal field generated by Er$^{3+}$ magnetic moments was derived to be ~0.33meV. The result indicates that the internal field of Er$^{3+}$ magnetic moments contribute to the energy shift of the crystal-field excitations. The giant energy shift under fields could be attributed to the anisotropy of the large effective g-factor., 22 pages, 12 figures

Crystal-field excitations, for example in transition-metal oxides where a rare-earth element is used as a spacer between the transition-metal-oxide tetrahedra and octahedra, are assumed to be extremely robust with respect to external perturbations such as temperature. Using inelastic neutron scattering experiments, a giant shift of the energy of the lowest crystal-field excitation of Er3+ (4I15/2) in ErFeO3 from 0.30(2) meV to 0.75(2) meV was measured below the magnetic-ordering temperature of erbium at 4.1 K. Quantum-mechanical point-charge calculations of the crystal-field levels indicate that the shift is caused by the internal magnetic field created by the erbium spins themselves, which causes a Zeeman splitting of the erbium 4f electronic levels, and therefore a change in the energies of crystal-field transitions. To verify this explanation, the effect of an external magnetic field on the crystal-field excitations was measured by inelastic neutron scattering and compared to the field-dependent point-charge calculations. The existence of an internal magnetic exchange interaction will have implications for a deeper understanding of a broader group of phenomena such as multiferroic properties or spin frustration, which are a consequence of various competing electronic and magnetic exchange interactions., Comment: Before submission we had contacted all co-authors repeatedly if they have any scientific comments, questions, or concerns. After submission one co-author did rise scientific concerns. Since we were not able to solve this, we would like to withdraw our manuscript

We report the structural, magnetic, and magnetocaloric properties of Co$_2$Cr$_{1-x}$Ti$_x$Al ($x=$ 0--0.5) Heusler alloys for spintronic and magnetic refrigerator applications. Room temperature X-ray diffraction and neutron diffraction patterns along with Rietveld refinements confirm that the samples are of single phase and possess a cubic structure. Interestingly, magnetic susceptibly measurements indicate a second order phase transition from paramagnetic to ferromagnetic where the Curie temperature (T$_{\rm C}$) of Co$_2$CrAl increases from 330~K to 445~K with Ti substitution. Neutron powder diffraction data of the $x=$ 0 sample across the magnetic phase transition taken in a large temperature range confirm the structural stability and exclude the possibility of antiferromagnetic ordering. The saturation magnetization of the $x=$ 0 sample is found to be 8000~emu/mol (1.45~$\mu_{\rm B}$/{\it f.u.}) at 5~K, which is in good agreement with the value (1.35$\pm$0.05~$\mu_{\rm B}$/{\it f.u.}) obtained from the Rietveld analysis of the neutron powder diffraction pattern measured at temperature of 4~K. By analysing the temperature dependence of the neutron data of the $x=$ 0 sample, we find that the change in the intensity of the most intense Bragg peak (220) is consistent with the magnetization behavior with temperature. Furthermore, an enhancement of change in the magnetic entropy and relative cooling power values has been observed for the $x=$ 0.25 sample. Interestingly, the critical behavior analysis across the second order magnetic phase transition and extracted exponents ($\beta\approx$ 0.496, $\gamma\approx$ 1.348, and $\delta\approx$ 3.71 for the $x=$ 0.25 sample) suggest the presence of long-range ordering, which deviates towards 3D Heisenberg type interactions above T$_{\rm C}$, consistent with the interaction range value $\sigma$., Comment: submitted

The low-energy magnetic excitation from the highly Ca-doped quasi-one-dimensional magnet SrCa13Cu24O41 was studied in the magnetic ordered state by using inelastic neutron scattering. We observed the gapless spin-wave excitation, dispersive along the a and c axes but nondispersive along the b axis. Such excitations are attributed to the spin wave from the spin-chain sublattice. Model fitting to the experimental data gives the nearest-neighbour interaction Jc as 5.4 meV and the interchain interaction Ja = 4.4 meV. Jc is antiferromagnetic and its value is close to the nearest-neighbour interactions of the similar edge-sharing spin-chain systems such as CuGeO3. Comparing with the hole-doped spin chains in Sr14Cu24O41, which shows a spin gap due to spin dimers formed around Zhang-Rice singlets, the chains in SrCa13Cu24O41 show a gapless excitation in this study. We ascribe such a change from gapped to gapless excitations to holes transferring away from the chain sublattice into the ladder sublattice upon Ca doping.

Neutron powder diffraction experiments reveal that Co4Nb2O9 forms a noncollinear in-plane magnetic structure with Co2+ moments lying in the ab plane. The spin-wave excitations of this magnet were measured by using inelastic neutron scattering and soundly simulated by a dynamic model involving nearest and next-nearest neighbour exchange interactions, in-plane anisotropy and the Dzyaloshinskii-Moriya interaction. The in-plane magnetic structure of Co4Nb2O9 is attributed to the large in-plane anisotropy while the noncollinearity of the spin configuration is attributed to the Dzyaloshinskii-Moriya interaction. The high magnetoelectric coupling effect of Co4Nb2O9 in fields can be explained by its special in-plane magnetic structure., Comment: 13pages, 3 figures

Total knee arthroplasty (TKA) has become a success story. Nevertheless, today there are a growing number of arthroplasties that have to be revised. The revision of knee arthroplasty is a challenging procedure. During the last 20 years, there have been significant improvements in the development of implants, instruments, and strategies for revision. Additionally, navigation has assumed a growing role in primary TKA. It has been shown that navigation results in a superior alignment to that of manual implantation (Bathis et al. 2004; Jenny and Boeri 2001). Achieving perfect alignment is one of the major challenges in revision arthroplasty, and consequently B. Braun Aesculap launched a total knee revision (TKR) version of their navigation system OrthoPilot® in October 2008.

Use of the OrthoPilot navigation system (B. Braun Aesculap, Tuttlingen, Germany) in navigated revision surgery allows for precise alignment of components, restoration of the joint line, balance of the gaps, and filling of the bony defects by facilitating selection of appropriate implant sizes and wedges. Our study results confirm these benefits through clinical and radiologic evaluation of the first 46 cases in our series in which the system was used. Continuous feedback from the system during surgery confirms that the surgeon is using proper technique. The OrthoPilot navigation system simplifies revision surgery and helps produce successful patient outcomes.

The OrthoPilot TKA Version 4.2 (B. Braun-Aesculap, Tuttlingen, Germany) offers software support for orthopedic surgeons. The system provides nearly normal manual workflow, creates perfect cuts, allows for sophisticated management of soft tissue, and respects individual anatomies. The OrthoPilot TKA Version 4.2 displays information to guide surgical decisions. However, surgeons decide if the information will be used during the resection. The most important advancements in the Version 4.2 software are the calculation of perfect rotation of the femoral component and optimal gap balancing.

Tiermodelle, Familien-, Zwillings- und Adoptionsstudien belegen, dass genetische Faktoren neben Umwelteinflüssen eine bedeutende Rolle bei der Genese der Alkoholabhängigkeit spielen. Ebenso geht man von einer multifaktoriellen Ätiologie bei der Entstehung des Delirium tremens (DTs) während der Alkoholentgiftung aus. Ziel der Assoziationsstudie war es, einzelne disponierende Gene bzw. serologische Marker der Alkoholabhängigkeit und des DTs zu identifizieren. Dabei wurden mit Hilfe der Polymerasekettenreaktion (PCR) und anschließendem Restriktionsendonukleasenverdau Kandidatengene analysiert, denen eine gewisse Funktionalität zugesprochen wird. Es konnten 208 nach DSM IV alkoholabhängige Patienten und 102 gesunde Kontrollpersonen rekrutiert werden. 82 der alkoholabhängigen Patienten litten während der Alkoholentgiftung unter schweren Entzugserschienungen in Form eines DTs. Weder für den funktionellen Val/Met-Polymorphismus des katecholaminabbauenden Enzyms Katecholamin-O-methyltransferase (COMT) noch für einen 48bp-VNTR-Polymorphismus des Dopaminrezeptors DRD4 konnte eine signifikante Assoziation mit der Alkoholabhängigkeit bzw. dem DT hergestellt werden. Dagegen stellte sich ein signifikanter Zusammenhang zwischen dem DBH*444g/a-Polymorphismus und der DbetaH-Plasmaaktivität dar. Der DBH*444g/a-Polymorphismus ist mit der Diagnose "Alkoholabhängigkeit" assoziiert: das Allel a weist eine signifikant höhere Frequenz in der Gruppe der alkoholabhängigen Patienten auf. Ferner zeigte sich nach mindestens 22 Tagen Abstinenz eine signifikant erniedrigte DbetaH-Plasmaaktivität bei den alkoholabhängigen Patienten. Zwischen den Patienten mit DT und den Patienten mit nur leichten Entzugserscheinungen während der Entgiftung konnte bezüglich des DBH*444g/a-Polymorphismus und der DbetaH-Plasmaaktivität kein signifikanter Unterschied festgestellt werden. Die Daten deuten auf eine Alkoholabhängigkeit-assoziierte Verminderung der DbetaH-Plasmaaktivität hin, die möglicherweise durch den DBH*444g/a-Polymorphismus beeinflusst wird. Nach der vorliegenden Studie ergibt sich kein Hinweis auf eine Beteiligung der untersuchten Polymorphismen für die Ätiologie des DTs. Animal experiments, family studies, twin studies and adoption studies show that both environmental and genetic influences seem to play a critical role in the etiology of alcohol dependence. It also can be assumed that the emergence of delirium tremens (DT) during alcohol withdrawal is caused by various factors. The intention of this association study was to identify predisposing genes and serologic markers for alcohol dependence or DT. We analysed potential functional polymorphisms via polymerase chain reaction (PCR) and restriction fragment length polymorphism assay (RFLP). 208 patients fulfilling the criteria for alcohol dependence according to DSM IV and 102 healthy controls were recruited. 82 patients had a history of alcohol withdrawal DT. The functional Val/Met-polymorphism of the human catechol-O-methyltransferase gene and the 48bp-VNTR-polymorphism of the dopamine D4 receptor were neither significantly associated with the diagnosis of alcoholism nor DT during alcohol withdrawal. The dopamine-beta-hydroxylase (DbetaH) plasma activity turned out to be influenced by the DBH*444g/a-polymorphism. The DBH*444g/a-polymorphism is significantly associated with the diagnosis "alcohol dependence": allele a had a higher frequency in the group of alcohol dependent patients. In addition mean plasma DbetaH activity measured in alcoholic subjects after 22 days of abstinence was significantly lower than that observed in the control group. No difference was found between subjects with DT during withdrawal and subjects with mild withdrawal symptoms regarding plasma DbetaH activity and DBH*444g/a-polymorphism. The study shows an alcoholism-related reduction in plasma DbetaH activity which seems to be influenced by the DBH*444g/a-polymorphism. According to our data none of the analysed polymorphisms contributed to the etiology of the DT.

The aim of the study was to assess the consistency of the non-image-based navigation system OrthoPilot, Aesculap, Tuttlingen, Germany, in total knee arthroplasty (TKA) implantation in 5 European centers. Two hundred thirty-five TKAs implanted with this navigation system were matched (according to severity of the preoperative coronal deformation and body mass index) to a historical control group of 235 TKAs implanted with a conventional technique. Consistency of implantation was studied on a 3-month postoperative radiological control with coronal long-leg and sagittal standard x-rays. The use of the OrthoPilot navigation system allowed a statistically significant improvement in the consistent placement of both tibial and femoral components. In accordance with current literature, survival of the navigated implanted prostheses is expected to be longer.

The OrthoPilot (Aesculap, Tuttlingen, Germany) Knee Navigation System represents a computed tomography (CT)-free system. In older software versions, a rigid-body at the iliac crest was necessary to calculate the centre of the hip. The latest software versions, 3.0 and 4.0, use a new mathematical algorithm to reconstruct the mechanical axis. Using the OrthoPilot system, an intraoperative cinematic study can be done that results in calculation of the mechanical axis and navigation of resection cuts. According to flexion- and extension-gap balancing, the anterior/posterior (a.p.) position and rotation of the femoral component also are navigated. Thirty navigated SEARCH (Aesculap, Tuttlingen, Germany) total knee arthroplasties (TKA) using the software version 3.0 of an uninterrupted series were evaluated, versus 30 navigated knees using older software and a manual group. Results concerning alignment were determined to be superior to the older navigation and manual groups. The number of cases with a good mechanical axis, 0; low; or 2 of deviation from optimum, was reached in 17 of the manual, 19 of the older-version, and 27 of the newer-version navigation cases. More features were solved in a convincing manner. The numbers of ouliers were diminished. Navigation in TKA using the OrthoPilot has become more safe and effective.

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In this study, 117 patients who had received the e.motion FP prosthesis between 2001 and 2003 were followed up for 5.5 years to assess the clinical and radiological outcomes and survival of this mobile platform prosthesis. As this design is intended to improve the mobility of the replaced knee, particular emphasis was placed on the clinical and functional results. The hypothesis was that they would be comparable to the excellent results reported in the literature of state-of-the-art total knee arthroplasty. After 66months, the average Knee Society clinical and functional scores were 93.8 points (KSS-C) and 90.5 (KSS-F) points, respectively. The clinical and radiographical results were excellent, with a low rate of anterior knee pain of 2.3 %.