Characteristics of the ID-NOW™ test for the rapid detection of SARS-CoV-2.

OBJECTIVE: To determine the sensitivity and specificity of the Abbott ID-NOW™ test in the diagnosis of COVID-19. The test is based on the detection of the SARS-CoV-2 gene by isothermal amplification technology. METHODS: From 303 individuals, two nasopharyngeal swabs and one oropharyngeal swab were collected to be tested in parallel by the ID-NOW™ test and PCR test (Allplex™ SARS-CoV-2 Assay). A subgroup of 107 individuals presented to the public collection point for covid-19 at the Motol University Hospital during the dominance of the Delta variant, and the others were tested via the Adult Emergency Admission Department during the dominance of the Omicron variant. RESULTS: Of 297 valid samples, 43 were positive by the PCR assay and 33 were positive by the ID-NOW™ test (sensitivity 76.74%; 95% CI 61.37 to 88.24%). ID-NOW™ detected three samples as positive, but the positivity was not confirmed by PCR (specificity 98.82%; 95% CI 96.59 to 99.76%). A significant increase in sensitivity up to 100% is observed for samples with a higher viral load (with a PCR threshold cycle value below 30 or from patients with symptoms of COVID-19). The Delta or Omicron variant has no significant effect on the sensitivity of the test. CONCLUSION: Due to its ease of use and speed of result, ID-NOW™ is a suitable diagnostic tool for prompt assessment of a patient's infectivity. If, despite the negative ID-NOW™ result, the patient has symptoms of COVID-19, it is advised to perform a classic PCR test for SARS-CoV-2.

The sensitivity of SARS-CoV-2 antigen tests in the view of large-scale testing.

OBJECTIVES: Antigen tests have emerged as an alternative to SARS-CoV-2 diagnostic PCR, thought to be valuable especially for the screening of bigger communities. To check appropriateness of the antigen based testing, we determined sensitivity of two point-of-care antigen tests when applied to a cohort of COVID-19 symptomatic, COVID-19 asymptomatic and healthy persons. METHODS: We examined nasopharyngeal swabs with antigen test 1 (Panbio Covid-19 Ag Rapid Test, Abbott) and antigen test 2 (Standard F Covid-19 Ag FIA, SD Biosensor). An additional nasopharyngeal and oropharyngeal swab of the same individual was checked with PCR (Allplex SARS-nCoV-2, Seegene). Within a 4-day period in October 2020, we collected specimens from 591 subjects. Of them, 290 had COVID-19 associated symptoms. RESULTS: While PCR positivity was detected in 223 cases, antigen test 1 and antigen test 2 were found positive in 148 (sensitivity 0.664, 95%CI 0.599, 0.722) and 141 (sensitivity 0.623, 95%CI 0.558, 0.684) patients, respectively. When only symptomatic patients were analysed, sensitivity increased to 0.738 (95%CI 0.667, 0.799) for the antigen test 1 and to 0.685 (95%CI 0.611, 0.750) for the antigen test 2. The substantial drop in sensitivity to 12.9% (95%CI 0.067, 0.234) was observed for samples with the PCR threshold cycle above > 30. CONCLUSIONS: Low sensitivity of antigen tests leads to the considerable risk of false negativity. It is advisable to implement repeated testing with high enough frequency if the antigen test is used as a frontline screening tool, and to follow with PCR if it is applied to vulnerable populations.

Atopic Dermatitis and Psoriasis as Overlapping Syndromes.

METHODS: In this observational study, 38 children with concomitant AD and PS with a mean age of 6.5 ± 3.2 yrs were compared with 41 similar patients with AD only (5.3 ± 5.1 yrs) and 28 patients with PS only (6.4 ± 4.3 yrs). All patients underwent dermatological examinations, including determination of SCORAD and PASI scores. TNF-α, IFN-γ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-12, IL-17, IL-18, IL-22, I:-33, and TARC/CCL17 were measured by ELISA according to the manufacturer's instructions. RESULTS: Patients with concomitant AD and PS were frequently boys and overweight and had skin lesions equally distributed throughout the body. Children with concomitant AD and PS were more likely to report a family history of atopic disease than children with only AD or PS, and those with AD were more likely to report a family history of atopic disease than those with PS. Significant differences were observed in the concentration of IL-17 between patients with AD and PS and those with only AD or PS: 9.1 ± 3.7 pg/ml vs. 4.8 ± 2.9 pg/ml; and 9.1 ± 3.7 pg/ml vs. 5.2 ± 3.9 pg/ml, respectively (PD vs. AD, p = 0.01; PD vs. PS, p = 0.03). CONCLUSIONS: AD and PS can coexist. The role of T helper 17 cells may be more essential than believed.

Phonons in Ultrathin Oxide Films: 2D to 3D Transition in FeO on Pt(111).

The structural and magnetic properties of ultrathin FeO(111) films on Pt(111) with thicknesses from 1 to 16 monolayers (MLs) were studied using the nuclear inelastic scattering of synchrotron radiation. A distinct evolution of vibrational characteristics with thickness, revealed in the phonon density of states (PDOS), shows a textbook transition from 2D to 3D lattice dynamics. For the thinnest films of 1 and 2 ML, the low-energy part of the PDOS followed a linear ∝E dependence in energy that is characteristic for two-dimensional systems. This dependence gradually transforms with thickness to the bulk ∝E^{2} relationship. Density-functional theory phonon calculations perfectly reproduced the measured 1-ML PDOS within a simple model of a pseudomorphic FeO/Pt(111) interface. The calculations show that the 2D PDOS character is due to a weak coupling of the FeO film to the Pt(111) substrate. The evolution of the vibrational properties with an increasing thickness is closely related to a transient long-range magnetic order and stabilization of an unusual structural phase.

The influence of non-specific anti-pruritus treatment with cyclosporine A on transepidermal water loss (TEWL) in natural atopic dermatitis in dogs.

Atopic dermatitis is a common allergic skin disease in dogs. Monitoring the progress of treatment and the assessment of the severity of disease symptoms are crucial elements of the treatment procedure. One of the common means of assessing the severity of the clinical signs of the disease is the CADESI 03. Research studies have pointed to a possibility of assessing the severity of skin lesions by means of measuring biophysical skin parameters such as TEWL, skin hydration and erythema intensity. The aim of the study was the assessment of changes in TEWL and CADESI values measured in ten different body regions during non-specific anti-pruritus treatment. The examination was performed on ten dogs with atopic dermatitis (age from 2.5 years to 7 years, mean age 3.8 years). The measurements were performed in the following body regions: the lumbar region, the right axillary fossa, the right inguinal region, the ventral abdominal region, the right lateral thorax region, the internal surface of the auricle, interdigital region of the right forelimb, cheek, bridge of nose and the lateral site of antebrachum. A statistically significant decrease in CADESI values was reported starting from the second week of treatment. In the case of the mean TEWL values, a fall was observed after one week of treatment in the ventral abdominal region and the interdigital region, after two weeks of treatment in the axillary fossa and the inguinal region, and after three weeks in the cheek and the lateral thorax region. There was no statistically significant decrease in TEWL values in the course of treatment in four other regions.

[Diagnosis of Clostridium difficile infections: comparative study of two immuno enzyme assays with confirmation by PCR and culture followed by PCR ribotyping]. / Diagnostika Clostridium difficile infekcí - porovnávací studie dvou imunoenzymatických metod s konfirmací pomocí PCR a kultivace s následnou ribotypizací kmene*

STUDY OBJECTIVE: Comparison of two commercially avail-able tests for the detection of Clostridium difficile Glutamate Dehydrogenase (GDH) and toxins A and B for their sensitivity and specificity. MATERIAL AND METHODS: Eighty-six stool samples from patients hospitalised in the Motol University Hospital were analysed. GDH and toxins A and B were assayed in parallel by two tests: C. difficile Quik Chek Complete® (Techlab, USA) and Liaison® C. difficile GDH and Toxins AαB (DiaSorin, USA). From the stool samples, nucleic acids were also isolated using the UltraClean® Fecal DNA kit (MoBio Laboratories, USA). The commercially available C. difficile Elite MGB® kit (Nanogen, Italy) was used for the polymerase chain reaction (PCR). Anaerobic culture on C. difficile selective medium (Oxoid) was performed for all positive samples at least in one test. Pure isolates were characterized by PCR ribotyping. RESULTS: Thirty-six (42%) samples were GDH negative and toxin A/B negative by both tests. Twenty (23%) samples were GDH positive and toxin A/B positive by both tests. Nine (10%) samples were GDH positive and toxin negative by both tests, but were positive by PCR. Eleven (13%) samples that were GDH positive and toxin negative by both tests remained negative by PCR. Six (7%) samples only were GDH positive and toxin positive by the Liaison® test alone. Four (5%) samples were GDH-positive by theLiaison® test alone. Culture failure was observed in 11 (13%) samples, of which seven were positive by PCR. PCR was inhibited in five (6%) samples. The following toxigenic ribotypes: AI-3, 001, 002, 012,014, 017, 020, 049, 054, 078, 176, 203, and 413 and non-toxigenic ribotypes: AI-34, AI-61, 010, 485, 495, and 596 were identified. CONCLUSION: The Liaison® test had seven percent higher sensitivity for the detection of toxins A/B. The two-step protocol of the tests is also cost-saving. The savings can be used e.g. for incorporating the PCR techniques into the diagnostic algorithm of the laboratory.

Transfer of magnetic anisotropy in epitaxial Co/NiO/Fe trilayers.

The magnetic properties of Co(10 Å)/NiO(40 Å)/Fe trilayer epitaxially grown on W(110) substrate were investigated with use of x-ray magnetic linear dichroism (XMLD) and x-ray magnetic circular dichroism (XMCD). We showed that magnetic anisotropy of Fe film that can be controlled by a thickness-driven spin reorientation transition is transferred via interfacial exchange coupling not only to NiO layer but further to ferromagnetic Co overlayer as well. Similarly, a temperature driven spin reorientation of Fe sublayer induces a reorientation of NiO spin orientation and simultaneous switching of the Co magnetization direction. Finally, by element specific XMCD and XMLD magnetic hysteresis loop measurements we proved that external magnetic field driven reorientation of Fe and Co magnetizations as well as NiO Néel vector are strictly correlated and magnetic anisotropy fields of Fe and Co sublayers are identical despite the different crystal structures.

The dynamics of the non-heme iron in bacterial reaction centers from Rhodobacter sphaeroides.

We investigate the dynamical properties of the non-heme iron (NHFe) in His-tagged photosynthetic bacterial reaction centers (RCs) isolated from Rhodobacter (Rb.) sphaeroides. Mössbauer spectroscopy and nuclear inelastic scattering of synchrotron radiation (NIS) were applied to monitor the arrangement and flexibility of the NHFe binding site. In His-tagged RCs, NHFe was stabilized only in a high spin ferrous state. Its hyperfine parameters (IS=1.06±0.01mm/s and QS=2.12±0.01mm/s), and Debye temperature (θ(D0)~167K) are comparable to those detected for the high spin state of NHFe in non-His-tagged RCs. For the first time, pure vibrational modes characteristic of NHFe in a high spin ferrous state are revealed. The vibrational density of states (DOS) shows some maxima between 22 and 33meV, 33 and 42meV, and 53 and 60meV and a very sharp one at 44.5meV. In addition, we observe a large contribution of vibrational modes at low energies. This iron atom is directly connected to the protein matrix via all its ligands, and it is therefore extremely sensitive to the collective motions of the RC protein core. A comparison of the DOS spectra of His-tagged and non-His-tagged RCs from Rb. sphaeroides shows that in the latter case the spectrum was overlapped by the vibrations of the heme iron of residual cytochrome c(2), and a low spin state of NHFe in addition to its high spin one. This enabled us to pin-point vibrations characteristic for the low spin state of NHFe.

Hyperfine splitting and room-temperature ferromagnetism of Ni at multimegabar pressure.

Magnetic and elastic properties of Ni metal have been studied up to 260 GPa by nuclear forward scattering of synchrotron radiation with the 67.4 keV Mössbauer transition of 61Ni. The observed magnetic hyperfine splitting confirms the ferromagnetic state of Ni up to 260 GPa, the highest pressure where magnetism in any material has been observed so far. Ab initio calculations reveal that the pressure evolution of the hyperfine field, which features a maximum in the range of 100 to 225 GPa, is a relativistic effect. The Debye energy obtained from the Lamb-Mössbauer factor increases from 33 meV at ambient pressure to 60 meV at 100 GPa. The change of this energy over volume compression is well described by a Grüneisen parameter of 2.09.

Oxygen on an Fe monolayer on W(110): From chemisorption to oxidation.

The adsorption of oxygen on a pseudomorphic iron monolayer deposited on a W(110) surface was studied experimentally and theoretically. Standard surface characterization methods, such as Auger electron spectroscopy and low energy electron diffraction, and specific nuclear methods, such as conversion electron Mössbauer spectroscopy (CEMS) and nuclear resonant scattering of synchrotron radiation, combined with theoretical calculations based on the density functional theory allowed us to determine the structure of the oxygen adsorbate and the electronic properties of iron atoms with different oxygen coordinations. The oxygen-(3 × 2) structure on the iron monolayer was recognized and was interpreted to be a state with oxygen chemisorbed on the non-reconstructed surface with modest electron transfer from iron to oxygen. A transition from chemisorbed oxygen to the onset of Fe-oxidation is revealed by distinct changes in the CEMS spectra.

Tunable interplay between exchange coupling and uniaxial magnetic anisotropy in epitaxial CoO/Au/Fe trilayers.

We show that the interaction between ferromagnetic Fe(110) and antiferromagnetic CoO(111) sublayers can be mediated and precisely tuned by a nonmagnetic Au spacer. Our results prove that the thickness of the Fe and Au layers can be chosen to modify the effective anisotropy of the Fe layer and the strength of the exchange bias interaction between Fe and CoO sublayers. Well-defined and tailorable magnetic anisotropy of the ferromagnet above Néel temperature of the antiferromagnet is a determining factor that governs exchange bias and interfacial CoO spins orientation at low temperatures. In particular, depending on the room temperature magnetic state of Fe, the low-temperature exchange bias in a zero-field cooled system can be turned "off" or "on". The other way around, we show that exchange bias can be the dominating magnetic anisotropy source for the ferromagnet and it is feasible to induce a 90-degree rotation of the easy axis as compared to the initial, exchange bias-free easy axis orientation.

Tunable magnetic anisotropy of antiferromagnetic NiO in (Fe)/NiO/MgO/Cr/MgO(001) epitaxial multilayers.

We report on the magnetic properties of antiferromagnetic NiO(001) thin films in epitaxially grown NiO/MgO(dMgO)/Cr/MgO(001) system for different thicknesses of MgO, dMgO. Results of X-ray Magnetic Linear Dichroism show that together with an increase of dMgO, rotation of NiO spins from in-plane towards out-of-plane direction occurs. Furthermore, we investigated how the proximity of Fe modifies the magnetic state of NiO in Fe/NiO/MgO(dMgO)/Cr/MgO(001). We proved the existence of a multidomain state in NiO as a result of competition between the ferromagnet/antiferromagnet exchange coupling and strain exerted on the NiO by the MgO buffer layer.

Higher importance of interleukin 6 than classic tumor markers (carcinoembryonic antigen and squamous cell cancer antigen) in the diagnosis of esophageal cancer patients.

It has been suggested that interleukin 6 (IL-6) plays a potential role in the growth and progression of tumors, including esophageal cancer (EC). The aim of the study was to compare clinical significance of serum IL-6 with classic tumor markers - carcinoembryonic antigen (CEA) and squamous cell cancer antigen (SCC-Ag) - in EC patients in relation to its histological types - squamous cell carcinoma of esophagus (ESCC) and adenocarcinoma (AD) of esophagus. The study included 53 EC patients and 90 healthy subjects. Serum IL-6 and CEA levels were determined using immunoenzyme assays, while SCC-Ag - chemiluminescent assay. The diagnostic criteria and prognostic values for markers were defined. The levels of all proteins tested in EC, ESCC, and AD were higher than in healthy subjects. The percentage of elevated results was substantially higher for IL-6 (86%) than for CEA (30%) and SCC-Ag (24%) in EC, similarly as in ESCC (87%, 23%, and 33%) and AD (87%, 39%, and 13%, respectively) patients. Concentrations of IL-6 depended on distant metastases and patients' survival in EC and were significantly higher in ESCC patients with more advanced tumor stage and nodal metastases. The IL-6 area under receiver operating characteristic curve (0.92) was larger than for CEA (0.84) and SCC-Ag (0.62) in EC, likewise in ESCC (0.92, 0.87, 0.77) and AD (0.91, 0.79, 0.57, respectively). Our findings indicate better usefulness of IL-6 than classic tumor markers in the diagnosis of EC, especially in patients with ESCC.

Neohygrocybe pseudoingrata, a new grassland species from Slovakia and the Czech Republic.

Neohygrocybe pseudoingrata, a new waxcap species known from Slovakia and the Czech Republic, is characterised by its pale greyish coloured and often robust basidiomata (or sporocarps), nitrous smell, context without colour changes, hollow, contorted and compressed stipe and smooth or slightly fibrillose pileus surface. Based on morphology and DNA analysis of ITS and LSU sequences of the collected specimens, N. pseudoingrata belongs to Neohygrocybe sect. Neohygrocybe together with N. ovina, N. nitrata and N. ingrata. Collections of N. pseudoingrata form a well-supported clade in phylogenetic trees. Citation: Fuljer F, Zajac M, Boertmann D, Szabóová D, Kautmanová I (2022). Neohygrocybe pseudoingrata, a new grassland species from Slovakia and the Czech Republic. Fungal Systematics and Evolution 9: 11-17. doi: 10.3114/fuse.2022.09.02.

A prime-boost combination of a three-protein cocktail and multiepitopic MVA as a vaccine against Babesia bigemina elicits neutralizing antibodies and a Th1 cellular immune response in mice.

In the intraerythrocytic protozoan parasites of the genus Babesia both innate and adaptive immune responses are necessary to confer protection against clinical disease. In particular, the adaptive immune response involves the production of neutralizing antibodies as well as the presentation of parasite antigens to CD4+ T lymphocytes by professional antigen-presenting cells. Therefore, the development of alternative vaccines that replace the use of live attenuated strains should include relevant epitopes targeting both B and T cell responses. The aim of this study was to design new Babesia bigemina immunogens and evaluate the humoral and cellular responses in mice. To achieve this, three B. bigemina recombinant antigens called Apical Membrane Antigen 1 (AMA-1), Rhoptry Associated Protein 1 (RAP-1) and the Thrombospondin Related Anonymous Protein 1 (TRAP-1) were obtained. Besides, two recombinant modified vaccinia virus Ankara vectors coding for chimeric constructs containing bioinformatically predicted B and T cell epitopes from the same three antigens were generated. These immunogens were evaluated in prime-boost heterologous schemes. Among the combinations tested, priming with a cocktail of the three proteins followed by a booster immunization with a mix of both viruses induced the highest activation of IFN-γ+ CD4+ and CD8+ antigen-specific T cell responses. Remarkably, all vaccine schemes containing antigen cocktails also induced antibodies that were capable of neutralizing merozoite invasion of bovine erythrocytes in vitro at a level comparable to an anti B. bigemina hyperimmune bovine serum. Our results offer a new perspective for vaccines against B. bigemina combining bioinformatics predictions and prime-boost immunization regimes for future control measures against bovine babesiosis.

Coupling of collective motions of the protein matrix to vibrations of the non-heme iron in bacterial photosynthetic reaction centers.

Non-heme iron is a conservative component of type II photosynthetic reaction centers of unknown function. We found that in the reaction center from Rba. sphaeroides it exists in two forms, high and low spin ferrous states, whereas in Rsp. rubrum mostly in a low spin state, in line with our earlier finding of its low spin state in the algal photosystem II reaction center (Burda et al., 2003). The temperature dependence of the non-heme iron displacement studied by Mössbauer spectroscopy shows that the surrounding of the high spin iron is more flexible (Debye temperature ~165K) than that of the low spin atom (~207K). Nuclear inelastic scattering measurements of the collective motions in the Rba. sphaeroides reaction center show that the density of vibrational states, originating from non-heme iron, has well-separated modes between lower (4-17meV) and higher (17-25meV) energies while in the one from Rsp. rubrum its distribution is more uniform with only little contribution of low energy (~6meV) vibrations. It is the first experimental evidence that the fluctuations of the protein matrix in type II reaction center are correlated to the spin state of non-heme iron. We propose a simple mechanism in which the spin state of non-heme iron directly determines the strength of coupling between the two quinone acceptors (Q(A) and Q(B)) and fast collective motions of protein matrix that play a crucial role in activation and regulation of the electron and proton transfer between these two quinones. We suggest that hydrogen bond network on the acceptor side of reaction center is responsible for stabilization of non-heme iron in different spin states.

Milli-electronvolt monochromatization of hard X-rays with a sapphire backscattering monochromator.

A sapphire backscattering monochromator with 1.1 (1) meV bandwidth for hard X-rays (20-40 keV) is reported. The optical quality of several sapphire crystals has been studied and the best crystal was chosen to work as the monochromator. The small energy bandwidth has been obtained by decreasing the crystal volume impinged upon by the beam and by choosing the crystal part with the best quality. The monochromator was tested at the energies of the nuclear resonances of (121)Sb at 37.13 keV, (125)Te at 35.49 keV, (119)Sn at 23.88 keV, (149)Sm at 22.50 keV and (151)Eu at 21.54 keV. For each energy, specific reflections with sapphire temperatures in the 150-300 K region were chosen. Applications to nuclear inelastic scattering with these isotopes are demonstrated.

Regional deep hyperthermia in combination with whole brain radiotherapy (WBRT) in poor prognosis patients with brain metastases.

PURPOSE: The aim of this study is to assess for the first time, the role of regional deep hyperthermia in combination with radiotherapy and systemic therapy in patients with poor prognosis of brain metastases (GPI ≤ 2.5). METHODS: Patients with confirmed cerebral metastases and classified as GPI score ≤ 2.5 were included in this prospective study. Pretreatment stratification was defined as patients with 0-1 GPI score (Group A) and patients with 1.5-2.5 GPI score (Group B). HT was applied twice a week, 60 min per session, during RT by regional capacitive device (HY-DEEP 600WM system) at 13.56 MHz radiofrequency. RESULTS: Between June 2015 and June 2017, 15 patients and a total of 49 brain metastases were included in the protocol. All patients received all HT sessions as planned. RT and systemic therapy were also completed as prescribed. Tolerance to treatment was excellent and no toxicity was registered. Patients with HT effective treatment time longer than the median (W90time > 88%) showed better actuarial PFS at 6 and 12 months (100% and 66.7%, respectively) compared to those with less HT effective treatment time (50% and 0%, respectively) (p < 0.031). Median OS was 6 months (range 1-36 months). Stratification by GPI score showed a median OS of 3 months (CI 95% 2.49-3.51) in Group A and 8.0 months (CI 95% 5.15-10.41) in Group B (p = 0.035). CONCLUSIONS: Regional hyperthermia is a feasible and safe technique to be used in combination with RT in brain metastases patients, improving PFS and survival in poor prognostic brain metastasis patients.

Wheel running and environmental enrichment differentially modify exon-specific BDNF expression in the hippocampus of wild-type and pre-motor symptomatic male and female Huntington's disease mice.

Brain-derived neurotrophic factor (BDNF) is an essential neurotrophin and regulation of its expression is complex due to multiple 5' untranslated exons which are separately spliced to a common coding exon to form unique mRNA transcripts. Disruption of BDNF gene expression is a key to the development of symptoms in Huntington's disease (HD), a fatal neurodegenerative condition. Abnormal epigenetic modifications are associated with reduced gene expression in late-stage HD but such regulation of BDNF gene expression has yet to be investigated. We hypothesized that BDNF gene expression is altered in the HD hippocampus of pre-motor symptomatic R6/1 transgenic HD mice, correlating with a change in the DNA methylation profile. The effects of wheel-running and environmental enrichment on wild-type mice, in association with a proposed environment-mediated correction of BDNF gene expression deficits in HD mice, were also investigated. Using real-time PCR, levels of total BDNF mRNA were found to be reduced in the hippocampus of both male and female HD mice. Wheel-running significantly increased total BDNF gene expression in all groups of mice except male HD mice. In contrast, environmental enrichment significantly increased expression only in male wild-type animals. Further quantification of BDNF exon-specific transcripts revealed sex-specific changes in relation to the effect of the HD mutation and differential effects on gene expression by wheel-running and environmental enrichment. The HD-associated reduction of BDNF gene expression was not due to increased methylation of the gene sequence. Furthermore, environment-induced changes in BDNF gene expression in the wild-type hippocampus were independent of the extent of DNA methylation. Overall, the results of this study provide new insight into the role of BDNF in HD pathogenesis in addition to the mechanisms regulating normal BDNF gene expression.

Noncollinear magnetization structure at the thickness-driven spin-reorientation transition in epitaxial Fe films on W(110).

An in-plane spin-reorientation transition occurring during the growth of epitaxial Fe films on W(110) was studied in situ by using the nuclear resonant scattering of synchrotron radiation. The spin-reorientation transition originates at the Fe/W(110) interface and proceeds via a noncollinear spin structure resembling a planar domain wall that propagates towards the surface with increasing film thickness.