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Metal powders are key to metal additive manufacturing technologies such as powder bed fusion. These powder feedstocks experience a range of forces and physical phenomena both during the powder bed fusion process and additional post-processing stages that can alter their composition and material properties. To evaluate such effects, these powders need to be characterized, tested, and analyzed at critical stages of their lifecycles. This paper provides a review of the current state of the art for powder evaluation methods and their applicability for powder bed fusion production. Methods are categorized by the properties they evaluate, either particulate or bulk properties. Industry standards are identified for each method if applicable and the advantages and disadvantages of each are defined. Effects of these properties on the flowability and spreadability of powders are synthesized and practical management guidelines are defined. This paper aims at providing an overview of powder evaluation for powder bed fusion, practical considerations for the development of powder test and evaluation programs, and provide insights for future research undertakings in the field.

A series of isomeric bis-2,6-(monoalkoxyphenyl)pyridine and bis-2,6-(dialkoxyphenyl)pyridine ligands were synthesized and characterized. In order to prepare their chlorogold(III) complexes, intermediate chloromercury(II) complexes were first prepared, but unlike observations from previous studies where they were obtained impure and at best in moderate yield, here pure complexes were synthesized, many in rather high yields. Depending on the substitution pattern of the alkoxy chains on the ligands, mono- and/or dimercurated complexes were obtained, characterized by 1H, 13C{1H}, and 199Hg NMR spectroscopy as well as, in several cases, by X-ray crystallography. Factors that may explain this unusual reactivity are discussed. In most cases, transmetalation to the related chlorogold(III) complex proceeded smoothly, although lower yields were obtained when starting from doubly mercurated precursors. Prompted by the propensity of these ligands to mercurate, attempts were made to effect direct auration, but none was successful. However, dimeric, orthometalated complexes of palladium(II) could be prepared and were also amenable to transmetalation to the chlorogold(III) complex, providing for a mercury-free synthesis.

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1–6in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.

Achieving a high emission efficiency and a large luminescence asymmetry factor (glum) in a single molecule exhibiting circularly polarised thermally activated delayed fluorescence (CP-TADF) remains a formidable challenge. In this work, a proof-of-concept, liquid-crystalline CP-TADF molecule is proposed to realise high glumby taking advantage of the order inherent in liquid crystals. Employing a chiral dinaphthol-based CP-TADF molecule as the emissive unit, a pair of liquid-crystalline CP-TADF molecules (R/S-4) is synthesised viathe introduction of six mesogenic moieties. The enantiomers show intense emission at about 520 nm which has clear TADF and liquid-crystalline characteristics. Both enantiomers display symmetrical electronic circular dichroism (CD) and circular polarisation luminescence (CPL) signals as thin films. Impressively, relatively large glumvalues of 0.11 are realised for the films. Solution-processed devices were fabricated using R/S-4as the dopants, with the TADF molecule CzAcSF as the sensitiser. The OLEDs so prepared show a very high maximum external quantum efficiency of 21.2%, revealing a novel strategy for realising large glumvalues in CP-TADF.

We demonstrate a proof-of-concept of a new analytical technique to measure relative F atom exposure at the surfaces of fluorinated materials. The method is based on reactive-atom scattering (RAS) of Al atoms, produced by pulsed laser ablation of solid Al at 532 nm. The properties of the incident ground-state Al were characterized by laser-induced fluorescence (LIF); at typical ablation fluences, the speed distribution is approximately Maxwellian at ∼45000 K, with a most-probable kinetic energy of 187 kJ mol–1and a mean of 560 kJ mol–1When these Al atoms impact the surfaces of perfluorinated solids (poly(tetrafluorethylene), PTFE) or liquids (perfluoropolyether, PFPE), gas-phase AlF products are clearly detectable by LIF on the AlF A–X band. Quantitative AlF yields were compared for a small representative set of a widely studied family of ionic liquids based on the common 1-alkyl-3-methylimidazolium ([Cnmim]+) cation. Yields of (1.9 ± 0.2):1 were found from [C2mim][Tf2N] and [C8mim][Tf2N], containing the common fluorinated bis(trifluoromethylsulfonyl)imide anion ([Tf2N]−). This is in quantitative agreement with previous independent low-energy ion scattering (LEIS) measurements and consistent with other independent results indicating that the longer cationic alkyl chains cover a larger fraction of the liquid surface and hence reduce anion exposure. The expected null result was obtained for the ionic liquid [C2mim][EtSO4] which contains no fluorine. These results open the way for further characterization and the potential application of this new variant of the RAS-LIF method.

Tubal ectopic pregnancies can cause substantial morbidity or even death. Current treatment is with methotrexate or surgery. Methotrexate treatment fails in approximately 30% of women who subsequently require rescue surgery. Gefitinib, an epidermal growth factor receptor inhibitor, might improve the effects of methotrexate. We assessed the efficacy of oral gefitinib with methotrexate, versus methotrexate alone, to treat tubal ectopic pregnancy.

Our research question is to what extent, and under what circumstances, full automation in metro lines defines transit mode boundaries with respect to semi-rapid transit. The modeling approach is based on micro-economic appraisal. Automation, beside changing the investment and operation and maintenance cost profiles of metro lines, can improve some aspects of the user experience. The low marginal cost of frequency possible with automated metro may unlock both users’ benefits viareduced waiting times and crowding, and operator’s savings viashorter trains and smaller platforms and stations. We show how the user’s travel time components are structurally different under several configurations. In particular, we highlight the critical role that different demand and alignment patterns play in the mode comparison.

Before we get into the weeds of this thing and start arguing over such vital details as. say, the perfect number of socks to carry during Mountain Phase or the [...]

ABSTRACTTowards the end of the first millennium, a fundamental change in the fabric of Western European elite society occurred as families began to promote themselves not on the basis of kin-groups but of their personal wealth. Key to self-aggrandisement was the ownership of local power centres, into which aristocrats poured investment. In England, few of these magnate cores have been investigated archaeologically, and understanding relies on a small corpus of well-excavated sites. Eager to shift this dependence on excavated evidence, research at Laughton en le Morthen, South Yorkshire used a range of methods to reveal the origins of an aristocratic centre, and its transformation in the wake of the Norman Conquest. This included construction of a motte and bailey castle that was perhaps never used for military purposes, but was instead curated as a folly-type feature expressive of new lordly power. The results from Laughton not only allow the evolution of the site and its landscape to be mapped, but also shows the value of adopting diverse archaeological research methodologies for understanding medieval magnate cores.

Agency theory remains the dominant means of examining governance issues and ownership characteristics related to large organizations. Research in these areas within large organizations has increased our understanding, yet little [...]

It is argued that to make management research beneficial to managers, it is important that managers and researchers get into symbiotic partnerships. The significance of practice-relevant management research is stressed using data from real case studies of organizations.

The gas–liquid interface of ionic liquids (ILs) is critically important in many applications, for example, in supported IL phase (SILP) catalysis. Methods to investigate the interfacial structure in these systems will allow their performance to be improved in a rational way. In this study, reactive-atom scattering (RAS), surface tension measurements, and molecular dynamics (MD) simulations were used to study the vacuum interface of mixtures of partially fluorinated and normal alkyl ILs. The underlying aim was to understand whether fluorinated IL ions could be used as additives to modify the surface structure of one of the most widely used families of alkyl ILs. The series of ILs 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Cnmim][Tf2N]) with n= 4–12 were mixed with a fixed-length, semiperfluorinated analogue (1H,1H,2H,2H-perfluorooctyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C8mimF13][Tf2N]), forming [Cnmim](1–x)[C8mimF13]x[Tf2N] mixtures, where xis the bulk mole fraction of the fluorinated component. The RAS-LIF method combined O-atom projectiles with laser-induced fluorescence (LIF) detection of the product OH as a measure of surface exposure of the alkyl chains. For [C8mim](1–x)[C8mimF13]x[Tf2N] mixtures, RAS-LIF OH yields are below those expected from stoichiometry. There are quantitatively consistent negative deviations from linearity of the surface tension. Both results imply that the lower-surface-tension fluoroalkyl material dominates the surface. A similar deficit is found for alkyl chain lengths n= 4, 6, 8, and 12 and for all (nonzero) xinvestigated by RAS-LIF. Accessible-surface-area (ASA) analyses of the MD simulations for [Cnmim](1–x)[C8mimF13]x[Tf2N] mixtures qualitatively reproduce the same primary effect of fluoro-chain predominance of the surface over most of the range of n. However, there are significant quantitative discrepancies between MD ASA predictions and experiment relating to the strength of any n-dependence of the relative alkyl coverage at fixed x, and on the x-dependence at fixed n. These discrepancies are discussed in the context of detailed examinations of the surface structures predicted in the MD simulations. Potential explanations, beyond experimental artifacts, include inadequacies in the classical force fields used in the MD simulations or the inability of simple ASA algorithms to capture dynamical factors that influence RAS-LIF yields.

Stock ownership by employees eliminates agency problems, reduces perceived inequity of executive compensation and adds excitement to boring compensation plans when contingent on performance levels. It has corresponding assumption of risk and tax implications.

Neurotropic alphaherpesviruses initiate infection in exposed mucosal tissues and, unlike most viruses, spread rapidly to sensory and autonomic nerves where life-long latency is established1. Recurrent infections arise sporadically from the peripheral nervous system throughout the life of the host, and invasion of the central nervous system may occur, with severe outcomes2. These viruses directly recruit cellular motors for transport along microtubules in nerve axons, but how the motors are manipulated to deliver the virus to neuronal nuclei is not understood. Here, using herpes simplex virus type I and pseudorabies virus as model alphaherpesviruses, we show that a cellular kinesin motor is captured by virions in epithelial cells, carried between cells, and subsequently used in neurons to traffic to nuclei. Viruses assembled in the absence of kinesin are not neuroinvasive. The findings explain a critical component of the alphaherpesvirus neuroinvasive mechanism and demonstrate that these viruses assimilate a cellular protein as an essential proviral structural component. This principle of viral assimilation may prove relevant to other virus families and offers new strategies to combat infection.

The analysis of an organization's strength and weakness entails four stages. The first stage involves the initial survey of human resources, technology enhancement, infrastructure, procurement, logistics and operations. The second stage requires the categorization of the organizational strength and weaknesses. The third stage involves the investigation of the origin of competitive advantage. Lastly, an evaluation of competitive advantage regarding resources and capabilities is needed.

Byline: Duncan W. Irons, Peter H. Baylis, John M. Davison Keywords: Atrial natriuretic peptide; human pregnancy; metabolic clearance Abstract: OBJECTIVE: Our purpose was to determine whether human pregnancy alters the metabolic clearance and natriuretic effect of atrial natriuretic peptide. STUDY DESIGN: The metabolic clearance rate of atrial natriuretic peptide (ANP 99-126) was measured serially in nine normotensive primigravid women studied in early and late pregnancy and again 4 months post partum (nonpregnant). Metabolic clearance of atrial natriuretic peptide was determined by use of a two-tier constant infusion technique (6 and 12 ng/kg/min, respectively). Sodium excretion was determined from 30-minute urine collections taken before and during infusion of atrial natriuretic peptide at both 6 and 12 ng/kg/min. RESULTS: Basal plasma atrial natriuretic peptide levels increased with gestation: in early pregnancy 18.0 [+ or -] 2.7 pg/ml, in late pregnancy 22.6 [+ or -] 4.2 pg/ml, and post partum 19.5 [+ or -] 3.6 pg/ml. Infusion of atrial natriuretic peptide at 6 and 12 ng/kg/min produced two distinct physiologic plasma levels of atrial natriuretic peptide. The metabolic clearance rates for nonpregnant women and those in early and late pregnancy at 6 and 12 ng/kg/min, respectively, were 3.4 [+ or -] 0.4 and 2.9 [+ or -] 0.4 L/min at plasma atrial natriuretic peptide levels of 86.2 [+ or -] 13.2 and 179.8 [+ or -] 42.5 pg/ml, respectively, 4.3 [+ or -] 0.5 and 4.3 [+ or -] 0.5 L/min at plasma atrial natriuretic peptide levels of 61.1 [+ or -] 4.9 and 131 [+ or -] 20.9 pg/ml (p < 0.01, nonpregnant vs early pregnancy), and 3.8 [+ or -] 0.6 and 3.8 [+ or -] 0.5 L/min at plasma atrial natriuretic peptide levels of 72 [+ or -] 8.0 and 136 [+ or -] 18.3 pg/ml (p < 0.05, nonpregnant vs late pregnancy), respectively. Infusion of atrial natriuretic peptide produced natriuresis in both pregnant and nonpregnant states; sodium excretion (basal to atrial natriuretic peptide infusion at 12 ng/kg/min) increased from 133 [+ or -] 19 to 207 [+ or -] 18 [mu]mol/min, 129 [+ or -] 21 to 374 [+ or -] 35 [mu]mol/min, and 128 [+ or -] 20 to 221 [+ or -] 33 [mu]mol/min in nonpregnant women and those in early and late pregnancy, respectively. CONCLUSIONS: The metabolic clearance of atrial natriuretic peptide increased by 16 weeks' gestation and remained elevated thereafter. There appears to be no attenuation of the natriuretic effect of infused atrial natriuretic peptide in normotensive human pregnancy. (Am J Obstet Gynecol 1996;175:449-54.) Author Affiliation: Newcastle upon Tyne, United Kingdom Article History: Received 19 September 1995; Revised 1 December 1995; Accepted 19 February 1996 Article Note: (footnote) [star] From the Departments of Obstetrics and Gynaecologya and Medicine,b University of Newcastle upon Tyne., [star][star] Supported by a Northern Regional Research Training Fellowship and a Research Training Fellowship from Wellbeing (Royal College of Obstetricians and Gynaecologists, United Kingdom) (D.W.I.)., a Reprint requests: D.W. Irons, MB, BS, Department of Obstetrics and Gynaecology, Fourth Floor Leazes Wing, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP., aa 0002-9378/96 $5.00 + 0 6/1/72778

This article presents the results of a study of mission statements in 42 state health departments. The statements were examined in an effort to verify the components previously found in [...]

Elf Gabon decided to update the seismic data available for the Port Gentil region of Gabon by performing an extensive three-dimensional seismic survey of the Ile Mandji prospect area. The survey utilized Differential Global Positioning Systems, including a portable unit for use in urban areas. The testing was carefully planned with an emphasis on safety and cooperation with the local authorities and citizens., The exploration potential of the Port Gentil region, characterized by some of the earliest petroleum discoveries in Gabon, continues to be of important interest today. Existing infrastructure and close proximity [...]

The Gospel According to Deming: Is It Really New? Who can help being impressed with the economic miracle of Japan? After World War II Japanese products were a joke. Japanese [...]

Theories about humor and work have been developed from many different academic disciplines, and these theories can be applied to management. Humor can be used to increase arousal, the ability to cope, alienation, superiority, alertness, pleasure, and the ability to memorize. Most studies about humor have indicated that something is funny either because of its incongruity or as a result of the cognitive interpretation of physiological arousal. The application of humor in management can have both positive and negative effects. It may not always be easy to define the difference between joking and harassment.

Introduction: Birmingham Hip Resurfacing (BHR) implants may be combined with a conventional femoral stem to create a modular metal-on-metal total hip arthroplasty (BHR MoM THA). There is little outcome data regarding this construct. This study examines midterm outcomes of BHR MoM THA compared to oxidised zirconium total hip arthroplasty (THA).Methods: A retrospective institutional review identified all patients receiving BHR MoM THA between April 2005 and February 2011 and a matched control cohort of zirconium THA patients. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), and SF-12 Health status scores were obtained. Revisions and complications were collected from clinical records. Radiographs were assessed for evidence of component malposition, loosening, osteolysis, or heterotopic ossification.Results: 63 modular BHR MoM THA were identified in 61 patients (36 with BHR cups, 27 with R3 cups) and 63 zirconium THA in 58 matched controls. Mean follow-up was 58 months. 14 BHR MoM THA hips (22.2%) were revised (4 infections, 1 dislocation, 9 soft tissue reactions) compared to 3 (4.8%) zirconium THA (all infections). At latest follow-up, 18.4% of surviving BHR MoM THA hips were painful compared to 0.5% of zirconium THA controls (p< 0.001). WOMAC, HHS, and SF-12 did not differ significantly between surviving members of the 2 groups.Discussion: BHR MoM THA demonstrated a high revision rate, largely for adverse local soft tissue reaction and pain. Among those not revised, many reported some residual pain despite similar quality of life measures to those who received zirconium THA.

The complex bis(tetrabutylammonium) (trans-μ2:η2,η2-1,3-butadiene)bis(trichloroplatinate(II)), identified from its X-ray single-crystal structure, is formed when tetrabutylammonium hexachloroplatinate(IV) is irradiated in solution. In principle, the complex can exist in one of four conformers (combining cisand transisomers of the butadiene and synand antiarrangements of the two PtCl3–moieties) and DFT calculations suggest that three of these ought to be stable in solution in CDCl3. However, dissolving the anti,transconformer (identified from both crystallography and 13C{1H} MAS NMR spectroscopy) in solution leads to the formation of a second conformer, identified by a combination of NMR experiments, in amounts that depend on the solvent used. Then, on standing in solution, a third species forms that contains a single PtCl3–moiety. The identification and interconversion of these various species are discussed.

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 per cent of anthropogenic carbon dioxide emissions1–3. Climate-driven vegetation models typically predict that this tropical forest ‘carbon sink’ will continue for decades4,5. Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to 2015, at 0.66 tonnes of carbon per hectare per year (95 per cent confidence interval 0.53–0.79), in contrast to the long-term decline in Amazonian forests6. Therefore the carbon sink responses of Earth’s two largest expanses of tropical forest have diverged. The difference is largely driven by carbon losses from tree mortality, with no detectable multi-decadal trend in Africa and a long-term increase in Amazonia. Both continents show increasing tree growth, consistent with the expected net effect of rising atmospheric carbon dioxide and air temperature7–9. Despite the past stability of the African carbon sink, our most intensively monitored plots suggest a post-2010 increase in carbon losses, delayed compared to Amazonia, indicating asynchronous carbon sink saturation on the two continents. A statistical model including carbon dioxide, temperature, drought and forest dynamics accounts for the observed trends and indicates a long-term future decline in the African sink, whereas the Amazonian sink continues to weaken rapidly. Overall, the uptake of carbon into Earth’s intact tropical forests peaked in the 1990s. Given that the global terrestrial carbon sink is increasing in size, independent observations indicating greater recent carbon uptake into the Northern Hemisphere landmass10reinforce our conclusion that the intact tropical forest carbon sink has already peaked. This saturation and ongoing decline of the tropical forest carbon sink has consequences for policies intended to stabilize Earth’s climate.

The complexes [Pt(tolpy)Cl(L)] (tolpy = 2-(4-tolyl)pyridyl; L = dmso, dms, py, PPh3, CO) are precursors for the catalytic cleavage of C–C bonds and extrusion of CO from a series of unactivated ketones such as cyclohexanone; deuterium labeling experiments demonstrate the involvement of a transfer hydrogen step in the mechanism.

Reaction of [PtCl2(dmso)2] with 2,5-(dialkoxyphenyl)pyridine in HOAc leads to a dinuclear, acetate-bridged, metal−metal bonded complex of platinum(III); dmso in the presence of acid is found to be responsible for the oxidation. The dimer is analogous structurally to PdIIIdimers implicated in catalytic acetoxylation. Platinum dimers with longer alkoxy chains are shown to be unique examples of liquid crystals of platinum(III).

The host behavior of the compound 4,4′-(9-fluorenylidene)diphenol (H) bearing two rigid fluorenyl moieties and two alcohol functional groups was investigated in the presence of four alkylnitriles, namely acetonitrile (ACE), acrylonitrile (ACRY), propionitrile (PROP), and butyronitrile (BUT). Crystal growth of Hfrom each of these nitriles furnished 1:1 host:guest inclusion complexes in each instance. Computational methods were employed in order to compare the low energy conformations of Hwith the guest-free molecular structure in the crystal obtained from single crystal X-ray diffraction analysis. Each of the complexes crystallized in the monoclinic crystal system and the centrosymmetric space group P21/n, and the host packing was isostructural in each case. The nitrile guest compounds experienced a classical (host)O–H···N(guest) hydrogen bond with the host molecule, the H···N, O···N, and ∠DHA parameters being 1.97, 2.772(3) Å, 159° (H·ACE), 1.94, 2.759(2) Å, 166° (H·ACRY), 1.91, 2.738(3) Å, 167° (H·PROP), and 1.95, 2.779(2) Å, 171° (H·BUT); this bond was thus significantly shorter in the PROP-containing inclusion compound than in the remaining three clathrates. The thermal stabilities of the four complexes were also examined together with Hirshfeld surface considerations. Finally, lattice energy calculations were carried out and the results of these compared with the relative thermal stabilities of the four complexes.

X-ray single crystal structures are reported for 2:1 halogen-bonded complexes of 4-(N,N-dimethylamino)pyridine (DMAP) with 1,4- and 1,3-diiodotetrafluorobenzene and 1,3-diiodo-4,5,6-trifluorobenzene and for a 3:1 complex of DMAP with 1,3,5-triiodotrifluorobenzene. The complex between DMAP and 1,4-diiodotetrafluorobenzene shows the shortest halogen bond recorded for fluorinated iodoarenes. Model systems based on complexes between the same iodofluorobenzenes and ammonia are investigated by Hartree−Fock and DFT calculations to gain insights into the features of halogen bonding in di- and triiodo systems. The calculations reveal a weak charge-transfer component to the halogen bond and account for the lengthening of the C−I bond on complexation in terms of the C−I antibonding character observed within the localized molecular orbital describing the N···I bond.

Tick-borne diseases continue to threaten human health across the United States. Both active and passive tick surveillance can complement human case surveillance, providing spatio-temporal information on when and where humans are at risk for encounters with ticks and tick-borne pathogens. However, little work has been done to assess the concordance of the acarological risk metrics from each surveillance method. We used data on Ixodes scapularisand its associated human pathogens from Connecticut (2019–2021) collected through active collections (drag sampling) or passive submissions from the public to compare county estimates of tick and pathogen presence, infection prevalence, and tick abundance by life stage. Between the surveillance strategies, we found complete agreement in estimates of tick and pathogen presence, high concordance in infection prevalence estimates for Anaplasma phagocytophilum, Borrelia burgdorferisensu stricto,and Babesia microti, but no consistent relationships between actively and passively derived estimates of tick abundance or abundance of infected ticks by life stage. We also compared nymphal metrics (i.e., pathogen prevalence in nymphs, nymphal abundance, and abundance of infected nymphs) with reported incidence of Lyme disease, anaplasmosis, and babesiosis, but did not find any consistent relationships with any of these metrics. The small spatial and temporal scale for which we had consistently collected active and passive data limited our ability to find significant relationships. Findings are likely to differ if examined across a broader spatial or temporal coverage with greater variation in acarological and epidemiological outcomes. Our results indicate similar outcomes between some actively and passively derived tick surveillance metrics (tick and pathogen presence, pathogen prevalence), but comparisons were variable for abundance estimates.

During data collection, the unreported potassium crown ether salt [K(18-crown-6][AuCl4] undergoes a sequential X-ray-induced and irreversible single-crystal to single-crystal transformation from P1̅ to C2/cfollowed by a topotactic reduction to crystalline [K(18-crown-6][AuCl2] within the same C2/cspace group.

This paper proposes an engineering approach at the microstructural scale to the problem of fatigue crack initiation. Initiation of an engineering fatigue crack approximately 0.2–0.4 mm in size is broken down into the separate processes of nucleation of a small facet, and subsequent short crack growth of the facet to an engineering crack. Engineering fatigue models frequently don't consider these processes separately and have difficulty predicting the total initiation life as the distributions of the separate processes are not known. A fundamental approach to modelling initiation life that tries to address these issues has been developed. A combination of crystal plasticity and the extended finite element method are used to model nucleation followed by short crack growth. The crack growth rate is calculated using the local stored energy at the crack tip, crack growth occurs on the crystallographic plane with the largest accumulated slip, thus allowing crack tortuosity to be modelled. A grain boundary hardening model has been developed which reduces the local stored energy available for growth at grain boundaries resulting in growth retardation. The levels of retardation experienced are in agreement with published data for a range of materials. The method has been successfully correlated with fatigue data for coarse grain RR1000. [ABSTRACT FROM AUTHOR]

We have shown previously that different homeostatic mechanisms in biochemistry create input-output curves with a “chair” shape. At equilibrium, for intermediate values of a parameter (often an input), a variable, Z, changes very little (the homeostatic plateau), but for low and high values of the parameter, Z changes rapidly (escape from homeostasis). In all cases previously studied, the steady state was stable for each value of the input parameter. Here we show that, for the feedback inhibition motif, stability may be lost through a Hopf bifurcation on the homeostatic plateau and then regained by another Hopf bifurcation. If the limit cycle oscillations are relatively small in the unstable interval, then the variable Z maintains homeostasis despite the instability. We show that the existence of an input interval in which there are oscillations, the length of the interval, and the size of the oscillations depend in interesting and complicated ways on the properties of the inhibition function, f , the length of the chain, and the size of a leakage parameter. [ABSTRACT FROM AUTHOR]

Realizing both a high emission efficiency and luminescence dissymmetry factor (glum) in circularly polarized solution processable organic light-emitting diodes (CP-OLEDs) remains a significant challenge. In this contribution, two chiral phosphorescent liquid crystals based on cyclometalated platinum complexes are prepared, in which the chiral s-2-methyl-1‑butyl group is introduced into the cyclometalating ligand and the mesogenic fragment is attached to the periphery of the ancillary ligand. The platinum complexes exhibit both smectic and chiral nematic phases as evidenced by polarized optical microscopy, differential scanning calorimetry and small-angle X-ray diffraction. Remarkably, a high photoluminescent quantum efficiency of over 78% and clear circularly polarized luminescent signal with gPLof about 10–2are observed for the complexes. Further, solution-processed CP-OLEDs show maximum external quantum efficiencies (EQE) of over 15% and strong circularly polarized electroluminescent signals with a gEL≈ 10–2. This research demonstrates that both liquid crystallinity and the number of chiral centers play key roles in improving the chiroptical property, paving the way for a new approach for the design of high-efficiency CPL emitters.

We report selected experimental results on the spin dynamics and spin freezing at ferromagnetic quantum phase transitions to illustrate some of the most prominent escape routes by which ferromagnetic quantum criticality is avoided in real materials. In the transition metal Heusler compound Fe2TiSn we observe evidence for incipient ferromagnetic quantum criticality. High pressure studies in MnSi reveal empirical evidence for a topological non-Fermi liquid state without quantum criticality. Single crystals of the hexagonal Laves phase compound Nb1−yFe2+yprovide evidence of a ferromagnetic to spin density wave transition as a function of slight compositional changes. Last but not least, neutron depolarisation imaging in CePd1−xRhxunderscore evidence taken from the bulk properties of the formation of a Kondo cluster glass.