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During semester one of 2020, the units ‘Functional Anatomy of the Trunk’ and ‘Functional Anatomy of the Limbs’ which focus on human topographical anatomy were re-designed into an online delivery format and taught remotely in response to the COVID-19 lockdown. It was expected that the move to remote teaching would negatively impact student perception and learning experience, in particular that of the cadaver-based laboratory work. The aim of this study was to investigate whether the replacement of traditional face-to-face cadaver-based anatomy laboratories with an online version using digital anatomy resources and Zoom technology as the communication platform would achieve comparable student learning experience and outcomes. First Year Students (n=69) enrolled in these units were invited to participate in this study and were asked at the conclusion of each unit to complete an anonymous opinion-based survey via Qualtrics. The Qualtrics data, student grades and Learning Management System (LMS) statistics were analysed. Results indicate that student perception of the online gross anatomy laboratory learning was positive and that it had complemented their learning. Most students agreed that as a visual learning resource, it provided an improved understanding of anatomy and helped with the application of anatomical knowledge. Interestingly, student performance showed a similar range of marks compared with previous years. However, students strongly agreed that the online 2D learning experience had significant limitations when compared to live use of cadavers in laboratories.

Vasculogenesis and angiogenesis are key processes of placental development, which occur throughout pregnancy. Placental vasculogenesis occurs during the first trimester of pregnancy culminating in the formation of hemangioblasts from intra-villous stem cells. Placental angiogenesis occurs subsequently, forming new blood vessels from existing ones. Angiogenesis also takes place at the fetomaternal interface, allowing essential spiral arteriole remodeling to establish the fetomaternal circulation. Vasculogenesis and angiogenesis in animal models and in humans have been studied in a wide variety of in vitro, physiological and pathological conditions, with a focus on the pro- and anti-angiogenic factors that control these processes. Recent studies revealed roles for new families of proteins, including direct participants such as the prokineticin family, and regulators of these processes such as the homeobox genes. This review summarizes recent advances in understanding the molecular mechanisms of actions of these families of proteins. Over the past decade, evidence suggests increased production of placental anti-angiogenic factors, as well as angiogenic factors are associated with fetal growth restriction (FGR) and preeclampsia (PE): the most threatening pathologies of human pregnancy with systemic vascular dysfunction. This review also reports novel clinical strategies targeting members of these family of proteins to treat PE and its consequent effects on the maternal vascular system.

We present the syntheses, structures, magnetic data and theoretical analyses for two families of heptanuclear clusters, wherein two staggered dysprosium(III) triangles are linked by various M(III) d-/p-block ions. The families differ in the counter-anion and are of formulae [DyIII6MIII(OH)8(o-tol)12(MeOH)5(NO3)] ⋅ 4MeOH and [DyIII6MIII(OH)8(o-tol)12(MeOH)6]Cl ⋅ 6MeOH (M=Cr, Mn, Fe, Co, Al; o-tol=o-toluate). We find that variation of the central metal ion M is crucial in tuning the toroidal moments on the triangular units, with diamagnetic M linking ions enhancing the ferrotoroidic coupling. By detailed simulation and analysis of various magnetic measurements, including sub-kelvin microSquid hysteresis loops, we identified the specific signature of the M linking ions’ modulation of toroidal properties, including the mechanism whereby anisotropic, paramagnetic M ions lead to hysteresis profiles with larger remnant magnetisations and broader coercive fields.

The first trigonal bipyramidal Fe(ii) complex to display slow relaxation of magnetisation has been isolated, with this behaviour found to arise through a combination of a large magnetic anisotropy (D = -27.5 cm-1) and a pseudo-D3h symmetry at the Fe(ii) centre, as investigated through ab initio and magnetic studies.

We reported earlier that an anti-inflammatory small peptide receptor-formyl peptide receptor-2 (FPR2) was significantly decreased in placentas from third trimester pregnancies complicated with fetal growth restriction (FGR), compared to placentas from uncomplicated control pregnancies, suggesting FPR2 may play a role in the development of FGR. The aim of this study is to investigate whether the actions of FPR2 alters placental growth process in humans. Accordingly, using small-for-gestation age (SGA) as a proxy for FGR, we hypothesize that FPR2 expression is decreased in first-trimester placentas of women who later manifest FGR, and contributes to aberrant trophoblast function and the development of FGR. Chorionic villus sampling (CVS) tissues were collected at 10-12 weeks gestation in 70 patients with singleton fetuses; surplus tissue was used. Real-time PCR and immunoassays were performed to quantitate FPR2 gene and protein expression. Silencing of FPR2 was performed in two independent, trophoblast-derived cell lines, HTR-8/SVneo and JEG-3 to investigate the functional consequences of FPR2 gene downregulation. FPR2 mRNA relative to 18S rRNA was significantly decreased in placentae from SGA-pregnancies (n = 28) compared with controls (n = 52) (p < 0.0001). Placental FPR2 protein was significantly decreased in SGA compared with control (n = 10 in each group, p < 0.05). Proliferative, migratory and invasive potential of the human placental-derived cell lines, HTR-8/SVneo and JEG-3 were significantly reduced in siFPR2 treated cells compared with siCONT control groups. Down-stream signaling molecules, STAT5B and SOCS3 were identified as target genes of FPR2 action in the trophoblast-derived cell lines and in SGA and control chorionic villous tissues. FPR2 is a novel regulator of key molecular pathways and functions in placental development, and its decreased expression in women destined to develop FGR reinforces a placental origin of SGA/FGR, and that it contributes to

© 2019 Elsevier Ltd Three tetranuclear {MnIII2LnIII2} ‘butterfly’ complexes with common MnIII2 µ3-alkoxo bridging motifs surrounded by two LnIII ions (Ln = Gd, La or Y) have been studied by structural, magnetic and density functional theoretical calculations. The exchange coupling constant between the body–body Mn(III) ions is ferromagnetic in all cases, the La and Y examples being diamagnetic at the wing-wing positions. The wing-body Jwb (Mn–Gd) interaction is small and negative. Reasons are given for these JMnMn values, including the effects of the terminal LnIII ions, comparison to analogous Mn2 dinuclears, and the effects of spin polarisation.

© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim We report four new complexes based on a {Ln III6 } wheel structure, three of which possess a net toroidal magnetic moment. The four examples consist of {Tb III6 } and {Ho III6 } wheels, which are rare examples of non Dy III based complexes possessing a toroidal magnetic ground state, and a {Dy III6 } complex which improves its toroidal structure upon lowering the crystallographic symmetry from trigonal (R (Formula presented.)) to triclinic (P (Formula presented.)). Notably the toroidal moment is lost for the trigonal {Er III6 } analogue. This suggests the possibility of utilizing the popular concept of oblate and prolate electron density of the ground state M J levels of lanthanide ions to engineer toroidal moments.

© 2019 The Royal Society of Chemistry. The structural, magnetic and theoretical aspects are described for three triangular lanthanide complexes, [TbIII3(OH)(teaH2)3(paa)3]Cl2 (1), [DyIII3(OH)(teaH2)3(paa)3]Cl2 (2) and [HoIII3(OH)(teaH2)3(paa)3]Cl2 (3), and a hexanuclear wheel of formula [DyIII6(pdeaH)6(NO3)6] (4) [teaH3 = triethanolamine, paaH = N-(2-pyridyl)-acetoacetamide and pdeaH3 = 3-[bis(2-hydroxyethyl)amino]propan-1-ol]. Each complex displays single molecule toroidal behaviour as rationalised using high-level ab initio calculations. Complexes 2 and 3 are the first examples of mixed moment single molecule toroidal complexes featuring non-Kramers ions.

© 2018 The Royal Society of Chemistry. We have synthesised twelve manganese(iii) dinuclear complexes, 1-12, in order to understand the origin of magnetic exchange (J) between the metal centres and the magnetic anisotropy (D) of each metal ion using a combined experimental and theoretical approach. All twelve complexes contain the same bridging ligand environment of one μ-oxo and two μ-carboxylato, that helped us to probe how the structural parameters, such as bond distance, bond angle and especially Jahn-Teller dihedral angle affect the magnetic behaviour. Among the twelve complexes, we found ferromagnetic coupling for five and antiferromagnetic coupling for seven. DFT computed the J and ab initio methods computed the D parameter, and are in general agreement with the experimentally determined values. The dihedral angle between the two Jahn-Teller axes of the constituent MnIII ions are found to play a key role in determining the sign of the magnetic coupling. Magneto-structural correlations are developed by varying the Mn-O distance and the Mn-O-Mn angle to understand how the magnetic coupling changes upon these structural changes. Among the developed correlations, the Mn-O distance is found to be the most sensitive parameter that switches the sign of the magnetic coupling from negative to positive. The single-ion zero-field splitting of the MnIII centres is found to be negative for complexes 1-11 and positive for complex 12. However, the zero-field splitting of the S = 4 state for the ferromagnetic coupled dimers is found to be positive, revealing a significant contribution from the exchange anisotropy-a parameter which has long been ignored as being too small to be effective.

© 2020 by the authors. We report the synthesis, structural and magnetic characterization of five mononuclear DyIII ion complexes using triphenylphosphine oxide as a monodentate ligand. They have formulae [DyIII(OPPh3)3(NO3)3] (1), [DyIII(OPPh3)4(NO3)2](NO3) (2), [DyIII(OPPh3)3Cl3] (3), [DyIII(OPPh3)4Cl2]Cl (4) and [DyIII(OPPh3)4Cl2](FeCl4) (5). These complexes are characterized using single crystal X-ray diffraction, which revealed that each complex has a unique coordination environment around the DyIII ion, which results in varying dynamic magnetic behavior. Ab initio calculations are performed to rationalize the observed magnetic behavior and to understand the effect that the ligand and coordination geometry around the DyIII ion has on the single-molecule magnet (SMM) behavior. In recent years, seven coordinate DyIII complexes possessing pseudo ~D5h symmetry are found to yield attractive blocking temperatures for the development of new SMM complexes. However, here we show that the strength of the donor ligand plays a critical role in determining the effective energy barrier and is not simply dependent on the geometry and the symmetry around the DyIII ion. Seven coordinate molecules possessing pseudo D5h symmetry with strong equatorial ligation and weak axial ligation are found to be inferior, exhibiting no SMM characteristics under zero-field conditions. Thus, this comprehensive study offers insight on improving the blocking temperature of mononuclear SMMs.

Understanding and controlling magnetic anisotropy at the level of a single metal ion is vital if the miniaturisation of data storage is to continue to evolve into transformative technologies. Magnetic anisotropy is essential for a molecule-based magnetic memory as it pins the magnetic moment of a metal ion along the easy axis. Devices will require deposition of magnetic molecules on surfaces, where changes in molecular structure can significantly alter magnetic properties. Furthermore, if we are to use coordination complexes with high magnetic anisotropy as building blocks for larger systems we need to know how magnetic anisotropy is affected by structural distortions. Here we study a trigonal bipyramidal nickel(ii) complex where a giant magnetic anisotropy of several hundred wavenumbers can be engineered. By using high pressure, we show how the magnetic anisotropy is strongly influenced by small structural distortions. Using a combination of high pressure X-ray diffraction, ab initio methods and high pressure magnetic measurements, we find that hydrostatic pressure lowers both the trigonal symmetry and axial anisotropy, while increasing the rhombic anisotropy. The ligand-metal-ligand angles in the equatorial plane are found to play a crucial role in tuning the energy separation between the d x2-y2 and d xy orbitals, which is the determining factor that controls the magnitude of the axial anisotropy. These results demonstrate that the combination of high pressure techniques with ab initio studies is a powerful tool that gives a unique insight into the design of systems that show giant magnetic anisotropy.

© 2017 American Chemical Society.Twelve heterovalent, tetranuclear manganese(II/III) planar diamond or “butterfly” complexes, 1-12, have been synthesized and structurally characterized, and their magnetic properties have been probed using experimental and theoretical techniques. The 12 structures are divided into two distinct “classes”. Compounds 1-8 place the Mn(III), S = 2, ions in the body positions of the butterfly metallic core, while the Mn(II), S = 5/2, ions occupy the outer wing sites and are described as “Class 1”. Compounds 9-12 display the reverse arrangement of ions and are described as “Class 2”. Direct current susceptibility measurements for 1-12 reveal ground spin states ranging from S = 1 to S = 9, with each complex displaying unique magnetic exchange parameters (J). Alternating current susceptibility measurements found that that slow magnetic relaxation is observed for all complexes, except for 10 and 12, and display differing anisotropy barriers to magnetization reversal. First, we determined the magnitude of the magnetic exchange parameters for all complexes. Three exchange coupling constants (Jbb, Jwb, and Jww) were determined by DFT methods which are found to be in good agreement with the experimental fits. It was found that the orientation of the Jahn-Teller axes and the Mn-Mn distances play a pivotal role in determining the sign and strength of the Jbb parameter. Extensive magneto-structural correlations have been developed for the two classes of {MnII2MnIII2} butterfly complexes by varying the Mnb-O distance, Mnw-O distance, Mnb-O-Mnb angle (α), Mnb-O-Mnb-O dihedral angle (γ), and out-of-plane shift of the Mnw atoms (β). For the magnetic anisotropy the DFT calculations yielded larger negative D value for complexes 2, 3, 4, and 6 compared to the other complexes. This is found to be correlated to the electron-donating/withdrawing substituents attached to the ligand moiety and suggests a possible way to fine tune the magnetic anisotropy in polyn

Four complexes containing DyIII and PrIII ions and their LnIII -ZnII analogs have been synthesized in order to study the influence that a diamagnetic ZnII ion has on the electronic structure and hence, the magnetic properties of the DyIII and PrIII single ions. Single-crystal X-ray diffraction revealed the molecular structures as [DyIII (HL)2 (NO3 )3 ] (1), [PrIII (HL)2 (NO3 )3 ] (2), [ZnII DyIII (L)2 (CH3 CO2 )(NO3 )2 ] (3) and [ZnII2 PrIII (L)2 (CH3 CO2 )4 (NO3 )] (4) (where HL=2-methoxy-6-[(E)-phenyliminomethyl]phenol). The dc and ac magnetic data were collected for all four complexes. Compounds 1 and 3 display frequency dependent out-of-phase susceptibility signals (χM "), which is a characteristic signature for a single-molecule magnet (SMM). Although 1 and 3 are chemically similar, a fivefold increase in the anisotropic barrier (Ueff ) is observed experimentally for 3 (83 cm-1 ), compared to 1 (16 cm-1 ). To rationalize the larger anisotropic barrier (1 vs. 3), detailed ab initio calculations were performed. Although the ground state Kramer's doublet in both 1 and 3 are axial in nature (gzz =19.443 for 1 and 18.82 for 3), a significant difference in the energy gap (Ueff ) between the ground and first excited Kramer's doublet is calculated. This energy gap is governed by the electrostatic repulsion between the DyIII ion and the additional charge density found for the phenoxo bridging ligand in 3. This extra charge density was found to be a consequence of the presence of the diamagnetic ZnII ion present in the complex. To explore the influence of diamagnetic ions on the magnetic properties further, previously reported and structurally related Zn-DyIII complexes were analyzed. These structurally analogous complexes unambiguously suggest that the electrostatic repulsion is found to be maximal when the Zn-O-Dy-O dihedral angle is small, which is an ideal condition to maximize the anisotropic barrier in DyIII complexes.

© 2017 American Chemical Society. The synthesis and magnetic and theoretical studies of three isostructural heterometallic [CoIII2LnIII2(μ3-OH)2(o-tol)4(mdea)2(NO3)2] (Ln = Dy (1), Tb (2), Ho (3)) "butterfly" complexes are reported (o-tol = o-toluate, (mdea)2- = doubly deprotonated N-methyldiethanolamine). The CoIII ions are diamagnetic in these complexes. Analysis of the dc magnetic susceptibility measurements reveal antiferromagnetic exchange coupling between the two LnIII ions for all three complexes. ac magnetic susceptibility measurements reveal single-molecule magnet (SMM) behavior for complex 1, in the absence of an external magnetic field, with an anisotropy barrier Ueff of 81.2 cm-1, while complexes 2 and 3 exhibit field induced SMM behavior, with a Ueff value of 34.2 cm-1 for 2. The barrier height for 3 could not be quantified. To understand the experimental observations, we performed DFT and ab initio CASSCF+RASSI-SO calculations to probe the single-ion properties and the nature and magnitude of the LnIII-LnIII magnetic coupling and to develop an understanding of the role the diamagnetic CoIII ion plays in the magnetization relaxation. The calculations were able to rationalize the experimental relaxation data for all complexes and strongly suggest that the CoIII ion is integral to the observation of SMM behavior in these systems. Thus, we explored further the effect that the diamagnetic CoIII ions have on the magnetization blocking of 1. We did this by modeling a dinuclear {DyIII2} complex (1a), with the removal of the diamagnetic ions, and three complexes of the types {KI2DyIII2} (1b), {ZnII2DyIII2} (1c), and {TiIV2DyIII2} (1d), each containing a different diamagnetic ion. We found that the presence of the diamagnetic ions results in larger negative charges on the bridging hydroxides (1b > 1c > 1 > 1d), in comparison to 1a (no diamagnetic ion), which reduces quantum tunneling of magnetization effects, allowing for more desirable SMM characteristics. The

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim We report the synthesis, structural characterisation, magnetic properties and provide an ab initio analysis of the magnetic behaviour of two new heterometallic octanuclear coordination complexes containing CoIIIand DyIIIions. Single-crystal X-ray diffraction studies revealed molecular formulae of [CoIII4DyIII4(μ-OH)4(μ3-OMe)4{O2CC(CH3)3}4(tea)4(H2O)4]⋅4 H2O (1) and [CoIII4DyIII4(μ-F)4(μ3-OH)4(o-tol)8(mdea)4]⋅ 3 H2O⋅EtOH⋅MeOH (2; tea3−=triply deprotonated triethanolamine; mdea2−=doubly deprotonated N-methyldiethanolamine; o-tol=o-toluate), and both complexes display an identical metallic core topology. Furthermore, the theoretical, magnetic and SMM properties of the isostructural complex, [CrIII4DyIII4(μ-F4)(μ3-OMe)1.25(μ3-OH)2.75(O2CPh)8(mdea)4] (3), are discussed and compared with a structurally similar complex, [CrIII4DyIII4(μ3-OH)4(μ-N3)4(mdea)4(O2CC(CH3)3)4] (4). DC and AC magnetic susceptibility data revealed single-molecule magnet (SMM) behaviour for 1–4. Each complex displays dynamic behaviour, highlighting the effect of ligand and transition metal ion replacement on SMM properties. Complexes 2, 3 and 4 exhibited slow magnetic relaxation with barrier heights (Ueff) of 39.0, 55.0 and 10.4 cm−1respectively. Complex 1, conversely, did not exhibit slow relaxation of magnetisation above 2 K. To probe the variance in the observed Ueffvalues, calculations by using CASSCF, RASSI-SO and POLY_ANISO routine were performed on these complexes to estimate the nature of the magnetic coupling and elucidate the mechanism of magnetic relaxation. Calculations gave values of JDy–Dyas −1.6, 1.6 and 2.8 cm−1for complexes 1, 2 and 3, respectively, whereas the JDy–Crinteraction was estimated to be −1.8 cm−1for complex 3. The developed mechanism for magnetic relaxation revealed that replacement of the hydroxide ion by fluoride quenched the quantum tunnelling of magnetisation (QTM) significantly, and led to improved SMM properties for

© 2017 The Author(s). Toroidal quantum states are most promising for building quantum computing and information storage devices, as they are insensitive to homogeneous magnetic fields, but interact with charge and spin currents, allowing this moment to be manipulated purely by electrical means. Coupling molecular toroids into larger toroidal moments via ferrotoroidic interactions can be pivotal not only to enhance ground state toroidicity, but also to develop materials displaying ferrotoroidic ordered phases, which sustain linear magneto-electric coupling and multiferroic behavior. However, engineering ferrotoroidic coupling is known to be a challenging task. Here we have isolated a {CrIIIDyIII6} complex that exhibits the much sought-after ferrotoroidic ground state with an enhanced toroidal moment, solely arising from intramolecular dipolar interactions. Moreover, a theoretical analysis of the observed sub-Kelvin zero-field hysteretic spin dynamics of {CrIIIDyIII6} reveals the pivotal role played by ferrotoroidic states in slowing down the magnetic relaxation, in spite of large calculated single-ion quantum tunneling rates.