Support for the "Vancouver call for action to strengthen expertise in radiological protection worldwide": the position of organisations in formal relations with the International Commission on Radiological Protection (ICRP).

The International Commission on Radiological Protection (ICRP), recently expressed concern that "a shortage of investment in training, education, research, and infrastructure seen in many sectors and countries may compromise society's ability to properly manage radiation risks" and in 2022 announced the "Vancouver call for action to strengthen expertise in radiological protection worldwide". As representatives of organisations in formal relations with ICRP, we decided to promote this position paper to declare and emphasise that strengthening the expertise in radiological protection is a collective priority for all of us.

Comprehensive inelastic neutron scattering study of the multiferroic M n 1 - x C o x W O 4 .

Using high-resolution inelastic neutron scattering, we examine the spin dynamics of M n 1 - x C o x W O 4 in the collinear AF1, the a c - b spiral AF2, and the a c cycloidal AF5 phases. The spin wave excitations are well described by a Heisenberg model with competing long-range exchange interactions ( J i up to 12th nearest neighbors) and the single-ion anisotropy K induced by the spin-orbit interaction. While the exchange constants are relatively unchanged, the dominant effect of doping is to change the single-ion anisotropy from easy axis ( K > 0 ) in the collinear AF1 phase to easy plane ( K < 0 ) in the two multiferroic phases.

Low Malignancy Rates in Fine-Needle Aspiration Cytologies in a Primary Care Setting in Germany.

BACKGROUND: Reported results for thyroid nodule fine-needle aspiration (FNA) cytology mainly originate from tertiary centers. However, thyroid nodule FNA cytology is mainly performed in primary care settings for which the distribution of FNA Bethesda categories and their respective malignancy rates are largely unknown. Therefore, this study investigated FNA cytology malignancy rates of a large primary care setting to determine to what extent current evidence-based strategies for the malignancy risk stratification of thyroid nodules are applied and applicable in such primary care settings. METHODS: In a primary care setting, 9460 FNAs of thyroid nodules were retrospectively analyzed from 8380 patients evaluated by one cytologist (I.R.) during a period of two years. The 8380 FNA cytologies were performed by 64 physicians in different private practices throughout Germany in primary care settings. RESULTS: The cytopathologic results were classified according to the Bethesda System as non-diagnostic in 19%, cyst/cystic nodule in 21%, benign (including thyroiditis) in 48%, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) in 6%, follicular neoplasms/suspicious for follicular neoplasm (FN/SFN) in 4%, suspicious for malignancy (SFM) in 1%, and malignant in 1%. The proportion of patients proceeding to surgery or with a follow-up of at least one year and the observed risks of malignancy were 22%/8% for AUS/FLUS, 69%/17% for FN/SFN, 78%/86% for SFM, and 71%/98% for malignant. For 112 cytologically suspicious and malignant FNAs, there were 102 true positives and 10 false positives, considering histology as gold standard. CONCLUSION: At variance with other data mostly originating from tertiary centers, these data demonstrate low percentages for malignant, SFM, FN/SFN, and AUS/FLUS, and high percentages for cysts/cystic nodules in this primary care setting in Germany. The risks of malignancy for malignant, SFM, AUS/FLUS, and FN/SFN FNA cytologies are according to Bethesda recommendations.

Evaluation of a Two-Year Routine Application of Molecular Testing of Thyroid Fine-Needle Aspirations Using a Seven-Gene Panel in a Primary Referral Setting in Germany.

BACKGROUND: Major differences with respect to the diagnostic performance of a "ruling in" approach in the presurgical diagnosis of indeterminate thyroid fine-needle aspirations (FNAs) have been reported. Therefore, the aim of this prospective multicenter study was to investigate the specific diagnostic impact of mutation testing using a seven-gene panel in a routine primary referral setting analyzing FNAs from endocrinology and nuclear medicine practices in Germany. METHODS: RNA and DNA was extracted from 564 routine air-dried FNA smears obtained from 64 physicians and cytologically graded by one experienced cytopathologist. PAX8/PPARG and RET/PTC rearrangements were detected by quantitative polymerase chain reaction, while BRAF and RAS mutations were detected by pyrosequencing. Molecular data were compared to histology and follow-up >1 year, which were available for 322/348 patients undergoing surgery and 33/74 patients having follow-up. Histology results were obtained from the local routine pathologists who were blinded to the molecular test results. RESULTS: BRAF and RET/PTC mutations were associated with carcinoma in 98% and 100% of samples, respectively. RAS and PAX8/PPARG mutations were associated with carcinoma in 31% and 0% of samples, respectively. Thirty-six percent of the carcinomas were identified by molecular testing in the atypia of undetermined significance/follicular lesion of undetermined significance and follicular neoplasm/suspicious for a follicular neoplasm categories, with malignancy rates of 15% and 17%, respectively. Due to a low percentage of RAS mutation-positive carcinomas in combination with a rather high percentage of RAS mutation-positive benign nodules, the positive predictive values of 41% and 36% in the atypia of undetermined significance/follicular lesion of undetermined significance and follicular neoplasm/suspicious for a follicular neoplasm categories offer only limited diagnostic potential. CONCLUSION: In conclusion, the data suggest that the application of the current seven-gene panel in a routine primary referral setting does not improve the presurgical diagnosis of thyroid FNAs. While the diagnostic relevance of RAS mutations in thyroid tumors needs further investigation, more comprehensive mutation panels with more cancer-specific mutations may improve the presurgical diagnosis of thyroid FNAs.

Polarization control at spin-driven ferroelectric domain walls.

Unusual electronic states arise at ferroelectric domain walls due to the local symmetry reduction, strain gradients and electrostatics. This particularly applies to improper ferroelectrics, where the polarization is induced by a structural or magnetic order parameter. Because of the subordinate nature of the polarization, the rigid mechanical and electrostatic boundary conditions that constrain domain walls in proper ferroics are lifted. Here we show that spin-driven ferroelectricity promotes the emergence of charged domain walls. This provides new degrees of flexibility for controlling domain-wall charges in a deterministic and reversible process. We create and position a domain wall by an electric field in Mn0.95Co0.05WO4. With a magnetic field we then rotate the polarization and convert neutral into charged domain walls, while its magnetic properties peg the wall to its location. Using atomistic Landau-Lifshitz-Gilbert simulations we quantify the polarization changes across the two wall types and highlight their general occurrence.

Nb2O2F3: a reduced niobium (III/IV) oxyfluoride with a complex structural, magnetic, and electronic phase transition.

A new niobium oxyfluoride, Nb2O2F3, synthesized through the reaction of Nb, SnO, and SnF2 in Sn flux, within welded Nb containers, crystallizes in a monoclinic structure (space group: I2/a; a = 5.7048(1)Å, b = 5.1610(1)Å, c = 12.2285(2)Å, ß = 95.751(1)°). It features [Nb2X10] units (X = O, F), with short (2.5739(1) Å) Nb-Nb bonds, that are linked through shared O/F vertices to form a 3D structure configurationally isotypic to ζ-Nb2O5. Nb2O2F3 undergoes a structural transition at ∼90 K to a triclinic structure (space group: P1̅; a = 5.1791(5)Å, b = 5.7043(6)Å, c = 6.8911(7)Å, α = 108.669(3)°, ß = 109.922(2)°, γ = 90.332(3)°). The transition is described as a disproportionation or charge ordering of [Nb2](7+) dimers: (2[Nb2](7+) → [Nb2](6+) + [Nb2](8+)), resulting in doubly (2.5000(9) Å) and singly bonded (2.6560(9) Å) Nb2 dimers. The structural transition is accompanied by an unusual field-independent "spin-gap-like" magnetic transition.

BaMn9[VO4]6(OH)2: a unique canted antiferromagnet with a chiral "paddle-wheel" structural feature.

BaMn(9)[VO(4)](6)(OH)(2) was synthesized by hydrothermal methods. We evaluated the crystal structure based on the two possible space groups P2(1)3 and Pa3̅ [a = 12.8417(2) Å] using single-crystal and powder X-ray diffraction techniques. The structure contains three-dimensionally linked Mn(9) units of a chiral "paddle-wheel" type. Experimental IR and Raman spectra were analyzed in terms of fundamental vanadate and hydroxide vibrational modes. The magnetic properties were investigated, and the specific heat in applied fields was studied. The dominant magnetic interactions (Mn(2+), S = 5/2) are of antiferromagnetic origin, as indicated by a Curie-Weiss fit above 175 K with Θ ≈ -200 K. Canting of the spins on the geometrically frustrated triangle segment of the structural feature is considered to account for the ferrimagnetic type of long-range order at T(C) ≈ 18 K. We propose a model for the spin structure in the ordered regime. Dielectric constants were measured and indicate a magnetodielectric effect at T(C), which is assigned to spin-lattice coupling.

Synthesis, structure, and superconductivity in the new-structure-type compound: SrPt6P2.

A metal-rich ternary phosphide, SrPt(6)P(2), with a unique structure type was synthesized at high temperatures. Its crystal structure was determined by single-crystal X-ray diffraction [cubic space group Pa3̅; Z = 4; a = 8.474(2) Å, and V = 608.51(2) Å(3)]. The structure features a unique three-dimensional anionic (Pt(6)P(2))(2-) network of vertex-shared Pt(6)P trigonal prisms. The Sr atoms occupy a 12-coordinate (Pt) cage site and form a cubic close-packed (face-centered-cubic) arrangement, and the P atoms formally occupy tetrahedral interstices. The metallic compound becomes superconducting at 0.6 K, as evidenced by magnetic and resistivity measurements.

The repeatability and reproducibility of the BioRID IIg in a repeatable laboratory seat based on a production car seat.

OBJECTIVE: The United Nations Economic Commission for Europe Informal Group on GTR No. 7 Phase 2 are working to define a build level for the BioRID II rear impact (whiplash) crash test dummy that ensures repeatable and reproducible performance in a test procedure that has been proposed for future legislation. This includes the specification of dummy hardware, as well as the development of comprehensive certification procedures for the dummy. This study evaluated whether the dummy build level and certification procedures deliver the desired level of repeatability and reproducibility. METHODS: A custom-designed laboratory seat was made using the seat base, back, and head restraint from a production car seat to ensure a representative interface with the dummy. The seat back was reinforced for use in multiple tests and the recliner mechanism was replaced by an external spring-damper mechanism. A total of 65 tests were performed with 6 BioRID IIg dummies using the draft GTR No.7 sled pulse and seating procedure. All dummies were subject to the build, maintenance, and certification procedures defined by the Informal Group. RESULTS: The test condition was highly repeatable, with a very repeatable pulse, a well-controlled seat back response, and minimal observed degradation of seat foams. The results showed qualitatively reasonable repeatability and reproducibility for the upper torso and head accelerations, as well as for T1 Fx and upper neck Fx . However, reproducibility was not acceptable for T1 and upper neck Fz or for T1 and upper neck My . The Informal Group has not selected injury or seat assessment criteria for use with BioRID II, so it is not known whether these channels would be used in the regulation. However, the ramping-up behavior of the dummy showed poor reproducibility, which would be expected to affect the reproducibility of dummy measurements in general. Pelvis and spine characteristics were found to significantly influence the dummy measurements for which poor reproducibility was observed. It was also observed that the primary neck response in these tests was flexion, not extension. This correlates well with recent findings from Japan and the United States showing a correlation between neck flexion and injury in accident replication simulations and postmortem human subjects (PMHS) studies, respectively. CONCLUSIONS: The present certification tests may not adequately control front cervical spine bumper characteristics, which are important for neck flexion response. The certification sled test also does not include the pelvis and so cannot be used to control pelvis response and does not substantially load the lumbar bumpers and so does not control these parts of the dummy. The stiffness of all spine bumpers and of the pelvis flesh should be much more tightly controlled. It is recommended that a method for certifying the front cervical bumpers should be developed. Recommendations are also made for tighter tolerance on the input parameters for the existing certification tests.

Ba(1-x)Na(x)Ti2Sb2O (0.0 ≤ x ≤ 0.33): a layered titanium-based pnictide oxide superconductor.

A new layered Ti-based pnictide oxide superconductor, Ba(1-x)Na(x)Ti(2)Sb(2)O (0.0 ≤ x ≤ 0.33), is reported. X-ray studies revealed that it crystallizes in the tetragonal CeCr(2)Si(2)C structure. The undoped parent compound, BaTi(2)Sb(2)O [P4/mmm; a = 4.1196(1) Å; c = 8.0951(2) Å], exhibits a charge density wave (CDW)/spin density wave (SDW) transition at 54 K. Upon chemical doping with Na, the CDW/SDW transition is systematically suppressed, and superconductivity arises with the critical temperature (T(c)) increasing to 5.5 K. Bulk superconductivity was confirmed by resistivity, magnetic, and heat capacity measurements. Like the high-T(c) cuprates and the iron pnictides, the superconductivity in BaTi(2)Sb(2)O arises from an ordered state. Similarities and differences between BaTi(2)Sb(2)O and the cuprate and iron pnictide superconductors are discussed.

[M(rac-N-benzyl Asp)(H2O)] (M = Co, Ni): noncentrosymmetric coordination polymeric chains with racemic chiral ligands.

The hydrothermal reaction of fumaric acid, benzylamine, and metal salts yielded M[(rac-N-benzyl-Asp)(H(2)O)] (M = Co, Ni), 1 and 2, and Ni[(rac-N-benzyl-Asp)(H(2)O)(3)]·H(2)O 3. Under mild hydrothermal conditions, Michael addition of benzylamine to fumaric acid led to the formation of a racemic mixture of N-benzyl aspartic acid enantiomers. The noncentrosymmetric structures of 1 and 2 consist of one-dimensional polymeric chains in which metal cations are bridged by d- and l-N-benzyl aspartate anions alternating along the chain. The centrosymmetric structure of 3 is composed of discrete Ni[(rac-N-benzyl-Asp)(H(2)O)(3)] units that are connected by hydrogen bonds into layers. The single layers are homochiral but are hydrogen bonded to similar homochiral layers that contain the N-benzyl aspartate with the opposite handedness. Compounds 1 and 2 showed second harmonic generation (SHG), and their magnetic and thermodynamic properties are described.

Unusual superconducting state at 49 K in electron-doped CaFe2As2 at ambient pressure.

We report the detection of unusual superconductivity up to 49 K in single crystalline CaFe(2)As(2) via electron-doping by partial replacement of Ca by rare-earth. The superconducting transition observed suggests the possible existence of two phases: one starting at 49 K, which has a low critical field < 4 Oe, and the other at 21 K, with a much higher critical field > 5 T. Our observations are in strong contrast to previous reports of doping or pressurizing layered compounds AeFe(2)As(2) (or Ae122), where Ae = Ca, Sr, or Ba. In Ae122, hole-doping has been previously observed to generate superconductivity with a transition temperature (T(c)) only up to 38 K and pressurization has been reported to produce superconductivity with a T(c) up to 30 K. The unusual 49 K phase detected will be discussed.

Synthesis, crystal structure, and physical properties of BaAg2Cu[VO4]2: a new member of the S = 1/2 triangular lattice.

By application of flux growth methods in combination with redox reactions, single crystals of BaAg(2)Cu[VO(4)](2) can be synthesized. A new structure type (triclinic, P1, Z = 2, a = 5.448(2) Å, b = 5.632(3) Å, c = 14.393(6) Å, α = 94.038(9)°, ß = 90.347(6)°, and γ = 118.195(5)°) has been found and will be described here. Structure-properties relationships have been investigated by spectroscopic methods (IR, UV-vis-NIR, ESR) and the electronic structure will be discussed within the angular-overlap model (AOM) for Cu(2+). Furthermore, we present the magnetization and specific heat data for BaAg(2)Cu[VO(4)](2) representing a Heisenberg spin system with exclusive super-super exchange (SSE) on a frustrated magnetic triangular lattice. Considerable antiferromagnetic (AFM) low-dimensional interaction is evident, and ferromagnetic-like long-range order sets in at ≈0.7 K.

Light-induced covalent immobilization of monolayers of magnetic nanoparticles on hydrogen-terminated silicon.

Specifically tailored ω-alkenyl-1-carboxylic acids were synthesized for use as surfactants in the single-step preparation of manganese ferrite (MnFe2O4) nanoparticles (NPs). Monodisperse manganese ferrite NPs terminated with ω-alkenyl moieties were prepared via a one-pot reaction at high temperature without the need of ligand exchange. Using this approach, simple adjustment of the rate of heating allowed precise tuning of the size of the nanoparticles, which were characterized in bulk form by transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). These surfactant-coated magnetic nanoparticles were then deposited onto hydrogen-terminated silicon(111) wafers and covalently anchored to the surface by UV-initiated covalent bonding. Analysis by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) confirmed that the UV treatment led to covalent immobilization of the NPs on the silicon surface with a consistent packing density across the surface. The magnetic properties of the stable, surface-bound nanoparticle arrays were characterized using a superconducting quantum interference device (SQUID) magnetometer. The materials and methods described here are being developed for use in bit-patterned ultrahigh density magnetic recording media and nanoscale biomagnetic sensing.

Superconducting Fe-based compounds (A1-xSrx)Fe2As2 with A=K and Cs with transition temperatures up to 37 K.

New high-T{c} Fe-based superconducting compounds, AFe2As2 with A=K, Cs, K/Sr, and Cs/Sr, were synthesized. The T{c} of KFe2As2 and CsFe2As2 is 3.8 and 2.6 K, respectively, which rises with partial substitution of Sr for K and Cs and peaks at 37 K for 50%-60% Sr substitution, and the compounds enter a spin-density-wave state with increasing electron number (Sr content). The compounds represent p-type analogs of the n-doped rare-earth oxypnictide superconductors. Their electronic and structural behavior demonstrate the crucial role of the (Fe2As2) layers in the superconductivity of the Fe-based layered systems, and the special feature of having elemental A layers provides new avenues to superconductivity at higher T{c}.

Remarkable rare-earth metal silicide oxides with planar Si6 rings.

New rare-earth silicide oxides, La10Si8O3 (1) and Ce10Si8O3 (2), were synthesized through high-temperature reactions of the pure elements under controlled oxygen atmosphere conditions. The remarkable silicides crystallize in a unique crystal structure (space group P6/mmm; a = 10.975(3) A (La) and 10.844(1) A (Ce); c = 4.680(1) A (La) and 4.561(1) A (Ce)) that features a 3-D framework of corner-shared O-centered (La/Ce)6 octahedra, reminiscent of hexagonal tungsten bronzes, with planar Si6 rings enclosed within its hexagonal channels. Band structure calculations indicate the compounds are metallic, with optimized La-Si bonds, and a benzene-like [Si6]6- anion. Compound 1 exhibits temperature independent paramagnetism. Compound 2 exhibits Curie-Weiss paramagnetism, and an antiferromagnetic ordering below 7 K.

Impairments of manual tracking performance during spaceflight are associated with specific effects of microgravity on visuomotor transformations.

In contrast to performance in cognitive tasks, tracking performance tends to deteriorate fairly consistently during spaceflight. We address the question whether this decrement results from specific effects of microgravity on motor control or from non-specific effects of the various other stressors present. In a case study we generalize the findings obtained with aiming movements, performed by the same cosmonaut with the same effectors as used for an unstable tracking task, to obtain hypotheses for specific changes of parameters of a simple model used to analyse tracking performance. Consistent with these hypotheses, we observed a reduction of limb stiffness in-flight, but a reduction of the tracking gain post-flight. The cross-task consistency of the observed changes does strongly suggest that the tracking impairment is at least partly caused by specific effects of microgravity on motor control, in particular by a mis-calibration of muscular forces which likely results from an underestimation of masses due to weightlessness.

Automated fault-management in a simulated spaceflight micro-world.

BACKGROUND: As human spaceflight missions extend in duration and distance from Earth, a self-sufficient crew will bear far greater onboard responsibility and authority for mission success. This will increase the need for automated fault management (FM). Human factors issues in the use of such systems include maintenance of cognitive skill, situational awareness (SA), trust in automation, and workload. This study examine the human performance consequences of operator use of intelligent FM support in interaction with an autonomous, space-related, atmospheric control system. METHODS: An expert system representing a model-base reasoning agent supported operators at a low level of automation (LOA) by a computerized fault finding guide, at a medium LOA by an automated diagnosis and recovery advisory, and at a high LOA by automate diagnosis and recovery implementation, subject to operator approval or veto. Ten percent of the experimental trials involved complete failure of FM support. RESULTS: Benefits of automation were reflected in more accurate diagnoses, shorter fault identification time, and reduced subjective operator workload. Unexpectedly, fault identification times deteriorated more at the medium than at the high LOA during automation failure. Analyses of information sampling behavior showed that offloading operators from recovery implementation during reliable automation enabled operators at high LOA to engage in fault assessment activities CONCLUSIONS: The potential threat to SA imposed by high-level automation, in which decision advisories are automatically generated, need not inevitably be counteracted by choosing a lower LOA. Instead, freeing operator cognitive resources by automatic implementation of recover plans at a higher LOA can promote better fault comprehension, so long as the automation interface is designed to support efficient information sampling.