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Qualitative research related to humans, dairy cows, calves and farming has been published by scientists from a variety of disciplines in many journals targeting dairy science audiences. We aimed to investigate how scientific communities other than those working in dairy science describe, analyze and discuss dairy farming, because we found it important to bring this research to the attention of dairy scientists. In total, 117 articles were identified as involving one or more qualitative research methods in relation to dairy cattle. The review brought out a wealth of perspectives, new insights and discussions related to dairy cattle, farmers, farming and the sector, and in relation to societal issues and food and ecological landscapes. A broad range of qualitative research methods were used, and the literature targeted issues at the animal, farm, societal, food system and landscape level. Some raised critical questions about existing structures, highlighted unfairness in the industry, or pointed to new potential futures and contemporary agendas. We expect that it will be inspirational and stimulating for researchers to review new sources of literature and suggest a closer interdisciplinary collaboration among researchers from different disciplines for the future development of research involving dairy cattle. Further, it could be relevant and even necessary to engage in such interaction to avoid increasing polarization around future development of the sector, for example related to climate change or how industrialization seems to push inequity or ignore the agency of animals themselves. Exploring perspectives of farming from different angles could enrich the outcomes of future dairy research.
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The objectives of this study were to understand dairy farmers' awareness and perceived barriers to the implementation of best management practices (BMP) for the transportation of lactating culled cows being moved to auction or abattoir. An invitation to participate was emailed to all dairy farms in Ontario, Canada. Responses to this invitation were used to recruit additional participants through criterion purposive snowball sampling. In total, 28 dairy producers participated in one of 5 semi-structured focus groups. All focus groups were audio recorded, transcribed verbatim, and analyzed with applied thematic analysis. Four themes were identified including 1) transfer of responsibility, 2) interpersonal relationships, 3) juggling priorities, and 4) complexities of long-term planning. While individual participant knowledge varied, participants described misconceptions that other producers held surrounding transport duration and distances, or the number of possible sales points for lactating culled cows. Participants did not agree whether the producer's responsibility ended once the cow left their property or if shared responsibility remained among all stakeholders from the farm to the final destination. Participants discussed the importance of existing trusted relationships with local cattle transporters and veterinarians to ensure information on best practices are shared. Participants also discussed how business pressures (e.g., production demands, space limitations) often challenge their ability to dry off lactating cows before transport; however, participants mentioned the degree of milk production may influence the destination of their animal (e.g., direct to slaughter for animals with high milk production). Some participants described a dynamic balance between business pressures and the potential for declining welfare of the animals under consideration to be culled during lactation. Participants posited that producers who did not prioritize proactive herd management and producers nearing retirement had limited long-term planning for culling individual cows, which might lead to transport of vulnerable or unfit animals. Finally, the lack of access to transportation direct to local slaughter was identified as an important barrier to adherence with the BMP for cull cows. In summary, many participants did not have an accurate understanding of what happens to cull cows after departing the farm and were unsure if they maintained a level of responsibility for an animal after being transported from their farm. Given the priority placed by participants on trusted interpersonal relationships, greater availability of peer-to-peer training of farmers and professional accreditation of animal transporters in addition to structural changes to increase local slaughter capacity may increase implementation of BMP and enhance lactating cull cow welfare.
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Spin-orbit coupling offers a large variety of novel and extraordinary magnetic and electronic properties in otherwise 'ordinary pool' of heavy ion oxides. Here we present a detailed study on an apparently isolated hexagonal 2Hspin-chaind4iridate Sr3LiIrO6with geometric frustration. Our structural studies reveal Li-Ir chemical order with desired stoichiometry in this compound, while x-ray absorption together with x-ray photoemission spectroscopic characterizations establish pure 5+ valence of Ir. We have established a magnetic ground state with finite Ir5+magnetic moments in this compound, contrary to the anticipated nonmagneticJeff= 0 state, through combined dc susceptibility,7Li nuclear magnetic resonance (NMR), muon spin relaxation (µSR) andab-initioelectronic structure studies. These investigations together with ac magnetic susceptibility and specific heat measurements reveal that despite having noticeable antiferromagnetic correlation among the Ir5+local moments, this system does not magnetically order down to at least 0.05 K, possibly due to geometrical exchange frustration, arising from the comparable nearest- and next-nearest-neighbor interchain Ir-O-O-Ir superexchange interaction strengths with opposite signs. However, the zero-fieldµSR analysis shows emergence of a considerable proportion of spin-freezing on top of a spin-fluctuating dynamic magnetic background down to the lowest measured temperature of 1.7 K, possibly due to some inhomogeneity and/or the much stronger intra-column Ir-Ir magnetic exchange interaction strength relative to the inter-column Ir-Ir ones. The linear temperature dependence of the magnetic specific heat (Cm) in both zero and applied magnetic fields, plus the power-law behavior of the NMR spin-lattice relaxation rate suggest a gapless spinon density of states in this charge gapped disordered magnetic ground state of Sr3LiIrO6.
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Automatic tracking of viral and intracellular structures displayed as spots with varying sizes in fluorescence microscopy images is an important task to quantify cellular processes. We propose a novel probabilistic tracking approach for multiple particle tracking based on multi-detector and multi-scale data fusion as well as Bayesian smoothing. The approach integrates results from multiple detectors using a novel intensity-based covariance intersection method which takes into account information about the image intensities, positions, and uncertainties. The method ensures a consistent estimate of multiple fused particle detections and does not require an optimization step. Our probabilistic tracking approach performs data fusion of detections from classical and deep learning methods as well as exploits single-scale and multi-scale detections. In addition, we use Bayesian smoothing to fuse information of predictions from both past and future time points. We evaluated our approach using image data of the Particle Tracking Challenge and achieved state-of-the-art results or outperformed previous methods. Our method was also assessed on challenging live cell fluorescence microscopy image data of viral and cellular proteins expressed in hepatitis C virus-infected cells and chromatin structures in non-infected cells, acquired at different spatial-temporal resolutions. We found that the proposed approach outperforms existing methods.
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Layered perovskites with Ruddlesden-Popper-type structures are fundamentally important for low-dimensional properties, for example, photovoltaic hybrid iodides and superconducting copper oxides. Many such halides and oxides are known, but analogous nitrides are difficult to stabilize due to the high cation oxidation states required to balance the anion charges. Here we report the high-pressure synthesis of three single-layer Ruddlesden-Popper (K2NiF4 type) nitrides-Pr2ReN4, Nd2ReN4 and Ce2TaN4-along with their structural characterization and properties. The R2ReN4 materials (R = Pr and Nd) are metallic, and Nd2ReN4 has a ferromagnetic Nd3+ spin order below 15 K. Thermal decomposition gives R2ReN3 with a Peierls-type distortion and chains of Re-Re multiply bonded dimers. Ce2TaN4 has a structural transition driven by octahedral tilting, with local distortions and canted magnetic Ce3+ order evidencing two-dimensional Ce3+/Ce4+ charge ordering correlations. Our work demonstrates that Ruddlesden-Popper nitrides with varied structural, electronic and magnetic properties can be prepared from high-pressure synthesis, opening the door to related layered nitride materials.
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A promising route to discover exotic electronic states in correlated electron systems is to vary the hole or electron doping away from a Mott insulating state. Important examples include quantum criticality and high-temperature superconductivity in cuprates. Here, we report the surprising discovery of a quantum insulating state upon electron doping the Mott insulator CeMnAsO, which emerges below a distinct critical transition temperature, TII. The insulator-insulator transition is accompanied by a significant reduction in electron mobility as well as a colossal Seebeck effect and slow dynamics due to decoupling of the electrons from the lattice phonons. The origin of the transition is tentatively interpreted in terms of many-body localization, which has not been observed previously in a solid-state material.
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We present a comprehensive study of PrIr3B2, which includes a detailed investigation of its crystal and magnetic structure using neutron diffraction. AC and DC magnetization and heat capacity data reveal antiferromagnetic ordering atTN= 10 K. The heat capacity measurements further exhibit a broad peak near 270 K which is related to a structural transition fromP6/mmmtoC2/mseen in low temperature x-ray diffraction and neutron diffraction. High intensity neutron diffraction data confirm the long-range ordering of Pr3+spins, with no apparent magnetic moment on either of the Iridium sites. Two possible magnetic structures with eitherk1= [1,0,0] ork2= [½,½,0] fit nearly equally well the neutron diffraction data. However, based on previous magnetization studies on a single crystalline sample it is argued that the second solution withk2corresponds to the appropriate magnetic structure of PrIr3B2below 10 K. In this magnetic structure, the Pr3+moments are oriented at â¼45° to both theaandbaxes, with thec-axis being the hard axis of magnetization. Overall, our results provide new insights into the magnetic and structural properties of PrIr3B2.
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The use of qualitative research in dairy science has increased considerably in recent years, providing the opportunity to inform research and practice. This review aims to enhance the accessibility of qualitative research among a range of audiences and specifically: (1) provide an overview of what qualitative research is and the value it can bring to scientific inquiries in the dairy context, (2) illustrate the emergence of qualitative dairy science research in the past 15 to 20 years, (3) outline the role of the researcher and key philosophical assumptions underlying qualitative research, (4) describe qualitative research approaches and methods used in dairy science research, and (5) highlight key aspects of qualitative inquiry used to ensure research trustworthiness. Qualitative approaches in dairy science enable researchers to understand myriad topics including stakeholder relationships, decision-making, and behaviors regarding dairy cattle management, animal welfare, and disease prevention and control measures. Approaches that were used often for qualitative data collection were individual interviews and focus groups, and variations of thematic analysis were common analytical frameworks. To assess public values, attitudes, and perceptions, mixed methods questionnaires that combined quantitative data with qualitative data from open-ended questions were used regularly. Although still used infrequently, action research and participatory approaches have the potential to bridge the research-implementation gap by facilitating group-based learning and on-farm changes. Some publications described the philosophical assumptions inherent to qualitative research, and many authors included reflexivity and positionality statements. Although a comprehensive description of strategies to meet trustworthiness criteria for qualitative research was uncommon, many publications mentioned certain aspects of trustworthiness, such as member checking, researcher triangulation, and the recording of reflexive notes. Qualitative research has been used to deepen our understanding of phenomena relevant to the dairy sector and has opened the door for a broad array of new opportunities. In addition to having merit on its own, qualitative research can guide, inform, and expand on quantitative research, and an understanding of the core pillars of qualitative research can foster interdisciplinary collaborations.
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Atitude , Bovinos , Animais , Pesquisa Qualitativa , Grupos Focais , FazendasRESUMO
Spiral spin liquids are an exotic class of correlated paramagnets with an enigmatic magnetic ground state composed of a degenerate manifold of fluctuating spin spirals. Experimental realizations of the spiral spin liquid are scarce, mainly due to the prominence of structural distortions in candidate materials that can trigger order-by-disorder transitions to more conventionally ordered magnetic ground states. Expanding the pool of candidate materials that may host a spiral spin liquid is therefore crucial to realizing this novel magnetic ground state and understanding its robustness against perturbations that arise in real materials. Here, we show that the material LiYbO_{2} is the first experimental realization of a spiral spin liquid predicted to emerge from the J_{1}-J_{2} Heisenberg model on an elongated diamond lattice. Through a complementary combination of high-resolution and diffuse neutron magnetic scattering studies on a polycrystalline sample, we demonstrate that LiYbO_{2} fulfills the requirements for the experimental realization of the spiral spin liquid and reconstruct single-crystal diffuse neutron magnetic scattering maps that reveal continuous spiral spin contours-a characteristic experimental hallmark of this exotic magnetic phase.
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Ordering of cations is important for controlling properties of ABO3 perovskites, and CaFeFeNbO6 is the first example of an Fe-based AA'BB'O6 double double perovskite, with Ca2+/Fe2+ ordered on A-site columns, and Fe3+/Nb5+ at the octahedral B-sites. Substantial (37%) antisite disorder of the latter cations leads to spin glassy magnetism below a freezing transition at 12 K. The CaMnFeNbO6 analogue also shows substantial cation disorder and spin glassy behaviour. Comparison of synthesis pressures for ordered materials based on different A-site transition metals, suggests that pressures of at least 14-18 GPa will be required to discover the expected plethora of double double perovskites based on A' cations smaller than Mn2+.
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Early cow-calf separation followed by individual housing of calves is standard practice on dairy farms. However, a growing body of evidence suggests that as awareness grows the public will oppose these practices, which could compromise the dairy industry's social license. Despite disagreement among different stakeholders over weighting and evaluations of effects of early separation (e.g., distress response, disease risk), recent systematic reviews indicate that there is little scientific evidence supporting this practice. The acceptability of alternative cow-calf management systems is unknown. We used a mixed methods survey with a convenience sample of 307 Canadians plus a representative sample of 1,487 Americans to investigate perceptions of these systems, examining the effects of providing social or foster cow contact following early separation or not separating cow-calf pairs. Attitudes and perceptions of animal welfare were more positive (on a 7-point scale where 1 is most negative, 7 is most positive, and 4 is a neutral midpoint) toward the system where calves were not separated from the cow (mean ± SE; 5.8 ± 0.07; 5.7 ± 0.07), compared with systems in which the calf was separated and individually housed (3.6 ± 0.07; 3.4 ± 0.07), separated and group housed (3.7 ± 0.07; 3.4 ± 0.07), or separated and kept with a foster cow (3.8 ± 0.07; 3.6 ± 0.07). Participants were consistent in their attitudes toward and perceptions of animal welfare within the system, suggesting that participants took a holistic and value-oriented approach to cow-calf management regarding separation. These results, in combination with many participants' concern for the importance of the mother cow-calf relationship and perceptions that severing of this bond was a breach of standard of care, suggest that there may be low acceptance of any cow-calf management system involving early separation as such systems are unlikely to resonate with underlying values.
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Bem-Estar do Animal , Indústria de Laticínios , Animais , Atitude , Canadá , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , HumanosRESUMO
Automatic tracking of viral structures displayed as small spots in fluorescence microscopy images is an important task to determine quantitative information about cellular processes. We introduce a novel probabilistic approach for tracking multiple particles based on multi-sensor data fusion and Bayesian smoothing methods. The approach exploits multiple measurements as in a particle filter, both detection-based measurements and prediction-based measurements from a Kalman filter using probabilistic data association with elliptical sampling. Compared to previous probabilistic tracking methods, our approach exploits separate uncertainties for the detection-based and prediction-based measurements, and integrates them by a sequential multi-sensor data fusion method. In addition, information from both past and future time points is taken into account by a Bayesian smoothing method in conjunction with the covariance intersection algorithm for data fusion. Also, motion information based on displacements is used to improve correspondence finding. Our approach has been evaluated on data of the Particle Tracking Challenge and yielded state-of-the-art results or outperformed previous approaches. We also applied our approach to challenging time-lapse fluorescence microscopy data of human immunodeficiency virus type 1 and hepatitis C virus proteins acquired with different types of microscopes and spatial-temporal resolutions. It turned out, that our approach outperforms existing methods.
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Algoritmos , Estruturas Virais , Teorema de Bayes , Humanos , Microscopia de FluorescênciaRESUMO
The magnetic ground state of polycrystalline Néel skyrmion hosting material GaV4S8has been investigated usingacsusceptibility and powder neutron diffraction. In the absence of an applied magnetic field GaV4S8undergoes a transition from a paramagnetic to a cycloidal state below 13 K and then to a ferromagnetic-like state below 6 K. With evidence fromacsusceptibility and powder neutron diffraction, we have identified the commensurate magnetic structure at 1.5 K, with ordered magnetic moments of 0.23(2) µBon the V1 sites and 0.22(1) µBon the V2 sites. These moments have ferromagnetic-like alignment but with a 39(8)° canting of the magnetic moments on the V2 sites away from the V4cluster. In the incommensurate magnetic phase that exists between 6 and 13 K, we provide a thorough and careful analysis of the cycloidal magnetic structure exhibited by this material using powder neutron diffraction.
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We have investigated the magnetic properties of a polycrystalline sample of NdOs2Al10using neutron diffraction and inelastic neutron scattering, magnetic susceptibility and heat capacity measurements. The magnetic susceptibility data reveal an antiferromagnetic transition atTN1= 2.2 K while the heat capacity data which extend to lower temperatures show a further transition atTN2= 1.1 K. The INS measurements detect four well-resolved crystal field excitations at 7.4, 12.4, 17.6 meV and 19.2 meV at 5 K. The positions and intensities of the observed CEF excitations and the temperature dependence of previously published single crystal susceptibility data are analysed based on the orthorhombic CEF model of theJ= 9/2 ground state multiplet of Nd3+ion. The neutron diffraction study reveals the magnetic structure atT= 1.6 K to be of sine wave type (κ= [0, 0.723, 0]) with an ordered state moment ofµNd3+= 1.59(1)µBaligned along thea-axis in agreement with the single ion crystal field anisotropy. This indicates that the magnetism of NdOs2Al10is governed by the RKKY interactions in agreement with otherRT2Al10(R= Nd, Sm, Tb,T= Fe, Ru and Os), but different to that ofR= Ce based compounds where anisotropic two ions interaction as well as Kondo interaction govern the anomalous direction of the ordered state moment.
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Pulmão/diagnóstico por imagem , Respiração com Pressão Positiva , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Idoso , COVID-19/diagnóstico por imagem , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Respiração com Pressão Positiva/métodos , Edema Pulmonar/virologia , Tomografia Computadorizada por Raios XRESUMO
TheR3TiSb5ternary compounds, withRa light rare earth (La to Sm) have been reported to crystallize with the anti-Hf5CuSn3-type hexagonal structure (Pearson's symbolhP18; space-groupP63/mcm, N. 193). An early article that reported possible superconductivity in some of these intermetallic phases (namely those withR= La, Ce, and Nd) caught our attention. In this work, we have now refined the crystal structure of theR3TiSb5compounds withR= Ce, Pr and Nd by Rietveld methods using high-resolution neutron powder diffraction data. The magnetic ground states of these intermetallics have been investigated by low-temperature magnetization and high-intensity neutron diffraction. We find two different magnetic transitions corresponding to two related magnetic structures atTN1= 4.8 K (k1= [0, 1/2, 1/8]) andTN2= 3.4 K (k2= [0, 0, 1/8]), respectively for Ce3TiSb5. However, the magnetic ordering appears to occur following a peculiar hysteresis: thek2-type magnetic structure develops only after thek1-type phase fraction has first slowly ordered with time and the size of the ordered Ce3+magnetic moment has become large enough to induce the second magnetic transition. AtT= 1.5 K the maximum amplitude of the Ce moment in the coexisting phases amounts toµCe= 2.15 µB. For Nd3TiSb5an antiferromagnetic ordering belowTN= 5.2 K into a relatively simpler commensurate magnetic structure with a magnetic moment ofµNd= 2.14(3)µBand magnetic propagation vector ofk= [0, 0, 0], was determined. No evidence of superconductivity has been found in Nd3TiSb5. Finally, Pr3TiSb5does not show any ordering down to 1.5 K in neutron diffraction while an antiferromagnetic ground state is detected in magnetization measurements. There is no sign of magnetic contribution from Ti atoms found in any of the studied compounds.
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We report time-of-flight neutron spectroscopy and neutron and x-ray diffraction studies of the 5d^{2} double perovskite magnets, Ba_{2}MOsO_{6} (M=Zn,Mg,Ca). These materials host antiferromagnetically coupled 5d^{2} Os^{6+} ions decorating a face-centered cubic (fcc) lattice and are found to remain cubic down to the lowest temperatures. They all exhibit thermodynamic anomalies consistent with a single phase transition at a temperature T^{*}, and a gapped magnetic excitation spectrum with spectral weight concentrated at wave vectors typical of type-I antiferromagnetic orders. However, while muon spin resonance experiments show clear evidence for time-reversal symmetry breaking below T^{*}, we observe no corresponding magnetic Bragg scattering signal. These results are shown to be consistent with ferro-octupolar symmetry breaking below T^{*}, and are discussed in the context of other 5d double perovskite magnets and theories of exotic orders driven by multipolar interactions.
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The structural properties of the Yb2Pd2(In1-x Sn x ) system were investigated at room temperature by synchrotron x-ray powder diffraction. All the inspected compositions (x = 0.0, 0.3, 0.4, 0.5, 0.6, 0.8, 0.9) crystallize in the tetragonal space group P4/mbm; the cell parameters exhibit a non-linear dependence on composition, whereas cell volume changes more regularly, with a minimum at x = 0.8. Samples with Sn content x = 0.5, 0.6, 0.9 were also analysed by neutron diffraction down to 0.5 K. No evidence for a structural transition can be detected at low temperature, whereas an antiferromagnetic ordering is observed, characterized by a propagation vectors k = (0,0,½). Magnetic moments order in the tetragonal ab-plane and the magnetic structure belongs to the Shubnikov magnetic space group P4/mbm.
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A closure experiment was conducted over Svalbard by comparing Lidar measurements and optical aerosol properties calculated from aerosol vertical profiles measured using a tethered balloon. Arctic Haze was present together with Icelandic dust. Chemical analysis of filter samples, aerosol size distribution and a full set of meteorological parameters were determined at ground. Moreover, scanning electron microscopy coupled with energy-dispersive X-ray (SEM-EDS) data were at disposal showing the presence of several mineralogical phases (i.e., sheet silicates, gypsum, quartz, rutile, hematite). The closure experiment was set up by calculating the backscattering coefficients from tethered balloon data and comparing them with the corresponding lidar profiles. This was preformed in three subsequent steps aimed at determining the importance of a complete aerosol speciation: (i) a simple, columnar refractive index was obtained by the closest Aerosol Robotic Network (AERONET) station, (ii) the role of water-soluble components, elemental carbon and organic matter (EC/OM) was addressed, (iii) the dust composition was included. When considering the AERONET data, or only the ionic water-soluble components and the EC/OM fraction, results showed an underestimation of the backscattering lidar signal up to 76, 53 and 45% (355, 532 and 1064â¯nm). Instead, when the dust contribution was included, the underestimation disappeared and the vertically-averaged, backscattering coefficients (1.45⯱â¯0.30, 0.69⯱â¯0.15 and 0.34⯱â¯0.08â¯Mm-1â¯sr-1, at 355, 532 and 1064â¯nm) were found in keeping with the lidar ones (1.60⯱â¯0.22, 0.75⯱â¯0.16 and 0.31⯱â¯0.08â¯Mm-1â¯sr-1). Final results were characterized by low RMSE (0.36, 0.08 and 0.04â¯Mm-1â¯sr-1) and a high linear correlation (R2 of 0.992, 0.992 and 0.994) with slopes close to one (1.368, 0.931 and 0.977, respectively). This work highlighted the importance of all the aerosol components and of the synergy between single particle and bulk chemical analysis for the optical property characterization in the Arctic.
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A systematic study of the physical properties and microscopic magnetism of Nd7Pd3 compound, which in the paramagnetic state crystallizes in the non-centrosymmetric hexagonal Th7Fe3-type structure (hP20-P63 mc; with a = 10.1367(1) Å and c = 6.3847(1) Å at 300 K), confirms multiple magnetic ordering transitions that occur upon cooling. Antiferromagnetic transition is observed at T N = 37 K, which is followed by ferromagnetic transformation at T C = 33 K. The first-order magnetic transition at T C is magnetoelastic: it involves a change of crystal symmetry from P63 mc to Cmc21 and leads to anisotropic changes of the unit cell parameters. While the antiferromagnetic structure is symmetry allowed in P63 mc, the ferromagnetic structure with magnetic moments along the a-direction of the original hexagonal unit cell induces the first order transition to Cmc21. Density functional theory calculations confirm the experimentally observed ground state with the a-axis as the easy magnetization direction.