Dominance of Cyclobutadienyl Over Cyclopentadienyl in the Crystal Field Splitting in Dysprosium Single-Molecule Magnets.

Replacing a monoanionic cyclopentadienyl (Cp) ligand in dysprosium single-molecule magnets (SMMs) with a dianionic cyclobutadienyl (Cb) ligand in the sandwich complexes [(η4 -Cb'''')Dy(η5 -C5 Me4 t Bu)(BH4 )]- (1), [(η4 -Cb'''')Dy(η8 -Pn† )K(THF)] (2) and [(η4 -Cb'''')Dy(η8 -Pn† )]- (3) leads to larger energy barriers to magnetization reversal (Cb''''=C4 (SiMe3 )4 , Pn† =1,4-di(tri-isopropylsilyl)pentalenyl). Short distances to the Cb'''' ligands and longer distances to the Cp ligands in 1-3 are consistent with the crystal field splitting being dominated by the former. Theoretical analysis shows that the magnetic axes in the ground Kramers doublets of 1-3 are oriented towards the Cb'''' ligands. The theoretical axiality parameter and the relative axiality parameter Z and Zrel are introduced to facilitate comparisons of the SMM performance of 1-3 with a benchmark SMM. Increases in Z and Zrel when Cb''' replaces Cp signposts a route to SMMs with properties that could surpass leading systems.

Thinking about hallucinations: why philosophy matters.

Introduction: Hallucinations research is increasingly incorporating philosophy or the work of philosophically trained individuals. We present three different ways in which this is successfully implemented to the enhancement of knowledge and understanding of hallucinations and related phenomena.Method: We review contributions from phenomenology, philosophy of cognitive science, and philosophy of science and psychiatry.Results: We demonstrate that these areas of philosophy make significant contributions to hallucinations research. Phenomenology gives us a sophisticated and critical understanding of the lived experience of hallucinations. Philosophy of cognitive science enables big-picture theorising and synthesis of ideas, as well as a critical engagement with new paradigms. Philosophy of science and psychiatry raises valuable and theoretically informed questions about diagnosis and categorisation.Conclusions: These contributions reflect both the methodological variety within philosophy and its relevance to the hallucinations researcher.

What parliamentarians think about Australia's post-COVID-19 aid program: The emerging 'cautious consensus' in Australian aid.

Since the onset of the COVID-19 pandemic, the Australian Government has been ambiguous in the way it has communicated the aid budget. On some occasions, it has sought to downplay increases in aid spending, while at other times it has sought to downplay cuts to aid spending. We draw on interviews with federal parliamentarians and key informants to understand these dynamics, in the context of obtaining their views on changes to Australia's post-COVID-19 aid policy. We find evidence that a new political consensus is forming around Australian aid. While this 'cautious consensus' countenances aid spending increases, motivated in part by humanitarian concerns but especially by anxiety about increasing Chinese influence in the region, these priorities are tempered by considerable concern about public backlash at a time of significant economic challenges for Australian citizens. Based on this evidence, we define the contours of an emerging 'cautious consensus' by showing how it will differ from the earlier 'golden consensus' era of Australian aid.

A Multi-Omic Huntington's Disease Transgenic Sheep-Model Database for Investigating Disease Pathogenesis.

BACKGROUND: The pathological mechanism of cellular dysfunction and death in Huntington's disease (HD) is not well defined. Our transgenic HD sheep model (OVT73) was generated to investigate these mechanisms and for therapeutic testing. One particular cohort of animals has undergone focused investigation resulting in a large interrelated multi-omic dataset, with statistically significant changes observed comparing OVT73 and control 'omic' profiles and reported in literature. OBJECTIVE: Here we make this dataset publicly available for the advancement of HD pathogenic mechanism discovery. METHODS: To enable investigation in a user-friendly format, we integrated seven multi-omic datasets from a cohort of 5-year-old OVT73 (n = 6) and control (n = 6) sheep into a single database utilising the programming language R. It includes high-throughput transcriptomic, metabolomic and proteomic data from blood, brain, and other tissues. RESULTS: We present the 'multi-omic' HD sheep database as a queryable web-based platform that can be used by the wider HD research community (https://hdsheep.cer.auckland.ac.nz/). The database is supported with a suite of simple automated statistical analysis functions for rapid exploratory analyses. We present examples of its use that validates the integrity relative to results previously reported. The data may also be downloaded for user determined analysis. CONCLUSION: We propose the use of this online database as a hypothesis generator and method to confirm/refute findings made from patient samples and alternate model systems, to expand our understanding of HD pathogenesis. Importantly, additional tissue samples are available for further investigation of this cohort.

Racing Fast and Slow: Defining the Tactical Behavior That Differentiates Medalists in Elite Men's 1,500 m Championship Racing.

Background: 1,500 m running has long been a blue ribbon event of track championship racing. The eventual medalists employ common tactical behaviors such as a fast sustained pace from the start (gun-to-tape), or, slow initial laps that precede a precisely timed race kick. Before the kick, there are positional changes caused by surging, that can go uncharacterized. The inter-relationship of surge events, tactical positioning, and kick execution may have important implications for eventual medal winning outcomes and require further definition. Methods: In a randomized order, three middle-distance running experts were provided publically available video (YouTube) of 16 men's 1,500 m championship races across, European, World and Olympic championships. Each expert determined the occurrence of surges (defined as any point in the 1,500 m after the first 300 m where an athlete repositions by ≥3 places; or noticeably dictates a raise in the pace from the front) and the race kick. Following a second level verification of expert observations, tactical behaviors (quantity and distance marker within each race) mean distance from the finish were compared between fast (≤3:34.00, n = 5), medium (>3:34.00- ≤3:41.99, n = 7) and slow (≥3:42.00, n = 4) race categories. Results: Before the race kick, there were more surges in slow (5 ± 1.7, mean ±90% confidence limits) vs. fast races (1 ± 0.4, very large difference, very likely). The final surge before the race kick occurred earlier in fast (704 ± 133 m from the finish) vs. medium (427 ± 83 m, large difference, most likely), and slow races (370 ± 137 m, large difference, most likely). At initiation of the race kick in fast races, large positional differences were found between eventual gold (2 ± 1.2; likely) and silver (2.2 ± 1.6; likely) vs. bronze medalists (4.4 ± 1.2). In slow races, positional differences were unclear between eventual gold (4.3 ± 4.7), silver (4.8 ± 4.8) and bronze medalists (5.3 ± 1.5). Regardless of category, the race kick occurred on the last lap, with unclear differences between fast 244 ± 92 m medium 243 ± 56 m and slow 236 ± 142 m races. Conclusions: Presenting tactical behaviors by race categorization (slow, medium, fast race times), provides a novel understanding of the nuance of racing tactics. The present findings highlight the importance of considering within race athlete decision making across multiple-race scenarios during championship preparation.

Magnetic hysteresis up to 80 kelvin in a dysprosium metallocene single-molecule magnet.

Single-molecule magnets (SMMs) containing only one metal center may represent the lower size limit for molecule-based magnetic information storage materials. Their current drawback is that all SMMs require liquid-helium cooling to show magnetic memory effects. We now report a chemical strategy to access the dysprosium metallocene cation [(Cp i Pr5)Dy(Cp*)]+ (Cp i Pr5, penta-iso-propylcyclopentadienyl; Cp*, pentamethylcyclopentadienyl), which displays magnetic hysteresis above liquid-nitrogen temperatures. An effective energy barrier to reversal of the magnetization of U eff = 1541 wave number is also measured. The magnetic blocking temperature of T B = 80 kelvin for this cation overcomes an essential barrier toward the development of nanomagnet devices that function at practical temperatures.

Rare-Earth Cyclobutadienyl Sandwich Complexes: Synthesis, Structure and Dynamic Magnetic Properties.

The potassium cyclobutadienyl [K2 {η4 -C4 (SiMe3 )4 }] (1) reacts with MCl3 (THF)3.5 (M=Y, Dy) to give the first rare-earth cyclobutadienyl complexes, that is, the complex anions [M{η4 -C4 (SiMe3 )4 }{η4 -C4 (SiMe3 )3 -κ-(CH2 SiMe2 }]2- , (2M ), as their dipotassium salts. The tuck-in alkyl ligand in 2M is thought to form through deprotonation of the "squarocene" complexes [M{η4 -C4 (SiMe3 )4 }2 ]- by 1. Complex 2Dy is a single-molecule magnet, but with prominent quantum tunneling. An anisotropy barrier of 323(22) cm-1 was determined for 2Dy in an applied field of 1 kOe, and magnetic hysteresis loops were observed up to 7 K.

Cyclopentadienyl Ligands in Lanthanide Single-Molecule Magnets: One Ring To Rule Them All?

The discovery of materials capable of storing magnetic information at the level of single molecules and even single atoms has fueled renewed interest in the slow magnetic relaxation properties of single-molecule magnets (SMMs). The lanthanide elements, especially dysprosium, continue to play a pivotal role in the development of potential nanoscale applications of SMMs, including, for example, in molecular spintronics and quantum computing. Aside from their fundamentally fascinating physics, the realization of functional materials based on SMMs requires significant scientific and technical challenges to be overcome. In particular, extremely low temperatures are needed to observe slow magnetic relaxation, and while many SMMs possess a measurable energy barrier to reversal of the magnetization ( Ueff), very few such materials display the important properties of magnetic hysteresis with remanence and coercivity. Werner-type coordination chemistry has been the dominant method used in the synthesis of lanthanide SMMs, and most of our knowledge and understanding of these materials is built on the many important contributions based on this approach. In contrast, lanthanide organometallic chemistry and lanthanide magnetochemistry have effectively evolved along separate lines, hence our goal was to promote a new direction in single-molecule magnetism by uniting the nonclassical organometallic synthetic approach with the traditionally distinct field of molecular magnetism. Over the last several years, our work on SMMs has focused on obtaining a detailed understanding of why magnetic materials based on the dysprosium metallocene cation building block {Cp2Dy}+ display slow magnetic relaxation. Specifically, we aspired to control the SMM properties using novel coordination chemistry in a way that hinges on key considerations, such as the strength and the symmetry of the crystal field. In establishing that the two cyclopentadienyl ligands combine to provide a strongly axial crystal field, we were able to propose a robust magneto-structural correlation for understanding the properties of dysprosium metallocene SMMs. In doing so, a blueprint was established that allows Ueff and the magnetic blocking temperature ( TB) to be improved in a well-defined way. Although experimental discoveries with SMMs occur more rapidly than quantitative theory can (currently) process and explain, a clear message emanating from the literature is that a combination of the two approaches is most effective. In this Account, we summarize the main findings from our own work on dysprosium metallocene SMMs, and consider them in the light of related experimental studies and theoretical interpretations of related materials reported by other protagonists. In doing so, we aim to contribute to the nascent and healthy debate on the nature of spin dynamics in SMMs and allied molecular nanomagnets, which will be crucial for the further advancement of this vibrant research field.

Single-molecule magnet properties of a monometallic dysprosium pentalene complex.

The pentalene-ligated dysprosium complex [(η8-Pn†)Dy(Cp*)] (1Dy) (Pn† = [1,4-(iPr3Si)2C8H4]2-) and its magnetically dilute analogue are single-molecule magnets, with energy barriers of 245 cm-1. Whilst the [Cp*]- ligand in 1Dy provides a strong axial crystal field, the overall axiality of this system is attenuated by the unusual folded structure of the [Pn†]2- ligand.

Activation of C-H bonds by rare-earth metallocene-butyl complexes.

The stable metallocene-butyl complexes [(CpMe)2M(nBu)]2 (M = Y, Dy) were synthesized and their reactivity towards to ferrocene and bulky N-heterocyclic carbenes investigated. Selective mono-deprotonation of ferrocene and a benzylic methyl group of IMes were observed, whereas a control reaction of (CpMe)3M with IMes resulted in a normal-to-abnormal NHC rearrangement.

A Dysprosium Metallocene Single-Molecule Magnet Functioning at the Axial Limit.

Abstraction of a chloride ligand from the dysprosium metallocene [(Cpttt )2 DyCl] (1Dy Cpttt =1,2,4-tri(tert-butyl)cyclopentadienide) by the triethylsilylium cation produces the first base-free rare-earth metallocenium cation [(Cpttt )2 Dy]+ (2Dy ) as a salt of the non-coordinating [B(C6 F5 )4 ]- anion. Magnetic measurements reveal that [2Dy ][B(C6 F5 )4 ] is an SMM with a record anisotropy barrier up to 1277 cm-1 (1837 K) in zero field and a record magnetic blocking temperature of 60 K, including hysteresis with coercivity. The exceptional magnetic axiality of 2Dy is further highlighted by computational studies, which reveal this system to be the first lanthanide SMM in which all low-lying Kramers doublets correspond to a well-defined MJ value, with no significant mixing even in the higher doublets.

A three-coordinate iron-silylene complex stabilized by ligand-ligand dispersion forces.

The structural and bonding properties of a three-coordinate N-heterocyclic silyene (NHSi) complex of the iron(ii) amide [Fe{N(SiMe3)2}2] are reported. Computational studies reveal that dispersion forces between the amido SiMe3 substituents and the isopropyl substituents on the NHSi ligand significantly enhance the stability of the complex, along with Fe-to-Si π-backbonding.

Strong Exchange Coupling in a Trimetallic Radical-Bridged Cobalt(II)-Hexaazatrinaphthylene Complex.

Reducing hexaazatrinaphthylene (HAN) with potassium in the presence of 18-c-6 produces [{K(18-c-6)}HAN], which contains the S=1/2 radical [HAN](.-) . The [HAN](.-) radical can be transferred to the cobalt(II) amide [Co{N(SiMe3 )2 }2 ], forming [K(18-c-6)][(HAN){Co(N'')2 }3 ]; magnetic measurements on this compound reveal an S=4 spin system with strong cobalt-ligand antiferromagnetic exchange and J≈-290 cm(-1) (-2 J formalism). In contrast, the Co(II) centres in the unreduced analogue [(HAN){Co(N'')2 }3 ] are weakly coupled (J≈-4.4 cm(-1) ). The finding that [HAN](.-) can be synthesized as a stable salt and transferred to cobalt introduces potential new routes to magnetic materials based on strongly coupled, triangular HAN building blocks.

Iron- and Cobalt-Catalyzed Synthesis of Carbene Phosphinidenes.

In the presence of stoichiometric or catalytic amounts of [M{N(SiMe3 )2 }2 ] (M=Fe, Co), N-heterocyclic carbenes (NHCs) react with primary phosphines to give a series of carbene phosphinidenes of the type (NHC)⋅PAr. The formation of (IMe4 )⋅PMes (Mes=mesityl) is also catalyzed by the phosphinidene-bridged complex [(IMe4 )2 Fe(µ-PMes)]2 , which provides evidence for metal-catalyzed phosphinidene transfer.

THE AFFORDABLE CARE ACT AND MEDICAL LOSS RATIOS: NO IMPACT IN FIRST THREE YEARS.

The Patient Protection and Affordable Care Act (ACA) set limits on insurers' overhead, mandating a medical loss ratio (MLR) of at least 80 percent in the individual and small-group markets and 85 percent in the large-group market starting in 2011. In implementing the law, the Obama administration introduced new rules that changed (and inflated) how insurers calculate MLRs, distorting time trends. We used insurers' filings with the U.S. Securities and Exchange Commission to calculate the largest insurers' MLRs before and after the ACA regulations took effect, using a constant definition of MLR. MLRs averaged 83.04 percent in the three years before reform and 83.05 percent in the three years after reform. We conclude that the ACA had no impact on insurance industry overhead spending.

Open-shell doublet character in a hexaazatrinaphthylene trianion complex.

Three-electron reduction of hexaazatrinaphthylene (HAN) with a magnesium(I) reagent leads to [(HAN){Mg(nacnac)}3] (1), containing a [HAN](3-) ligand with a spin of S = 1/2. Ab initio calculations reveal that the [HAN](3-) ligand in 1 has a ground-state wave function with multiconfigurational properties, and can be described as a triradicaloid species with a small amount of open-shell doublet character.

Molecular and electronic structures of donor-functionalized dysprosium pentadienyl complexes.

Two dysprosium complexes, [(C5H4Me)2Dy(L(1))] (3) and [(L(1))Dy(µ-Cl)3{Li(tmeda)}]2 (4), with amino-functionalized pentadienyl ligands L(1) are described. Crystallographic studies of 3 and 4 show that the pendant amino group influences the pentadienyl conformation and the ligand hapticity. Electronic structure calculations reveal that L(1) has a strong influence on the orientation of the main magnetic axis of the ground Kramers doublets in 3 and 4.

Inner experience in the scanner: can high fidelity apprehensions of inner experience be integrated with fMRI?

To provide full accounts of human experience and behavior, research in cognitive neuroscience must be linked to inner experience, but introspective reports of inner experience have often been found to be unreliable. The present case study aimed at providing proof of principle that introspection using one method, descriptive experience sampling (DES), can be reliably integrated with fMRI. A participant was trained in the DES method, followed by nine sessions of sampling within an MRI scanner. During moments where the DES interview revealed ongoing inner speaking, fMRI data reliably showed activation in classic speech processing areas including left inferior frontal gyrus. Further, the fMRI data validated the participant's DES observations of the experiential distinction between inner speaking and innerly hearing her own voice. These results highlight the precision and validity of the DES method as a technique of exploring inner experience and the utility of combining such methods with fMRI.