A new genus of Rhinotragini for \u3ci\u3eMolorchus laticornis\u3c/i\u3e Klug, 1825 (Coleoptera, Cerambycidae)

Klugiatragus gen. nov. is described for Epimelitta laticornis (Klug, 1825) because this species has closed procoxal cavities, a crucial diagnostic incompatible with Epimelitta Bates, 1870, which has open procoxal cavities. Both sexes of this species are illustrated

A new genus of Rhinotragini for \u3ci\u3eMolorchus laticornis\u3c/i\u3e Klug, 1825 (Coleoptera, Cerambycidae)

Klugiatragus gen. nov. is described for Epimelitta laticornis (Klug, 1825) because this species has closed procoxal cavities, a crucial diagnostic incompatible with Epimelitta Bates, 1870, which has open procoxal cavities. Both sexes of this species are illustrated

Y₂Ti₂O₅S₂ – a promising n-type oxysulphide for thermoelectric applications

Thermoelectric materials offer an unambiguous solution to the ever-increasing global demand for energy by harnessing the Seebeck effect to convert waste heat to electrical energy. Mixed-anion materials are ideal candidate thermoelectric materials due to their thermal stability and potential for “phonon-glass, electron-crystal” behaviour. In this study, we use density-functional theory (DFT) calculations to investigate Y2Ti2O5S2, a cation-deficient Ruddlesden-Popper system, as a potential thermoelectric. We use hybrid DFT to calculate the electronic structure and band alignment, which indicate a preference for n-type doping with highly anisotropic in-plane and the out-of-plane charge-carrier mobilities as a result of the anisotropy in the crystal structure. We compute phonon spectra and calculate the lattice thermal conductivity within the single-mode relaxation-time approximation using lifetimes obtained by considering three-phonon interactions. We also calculate the transport properties using the momentum relaxation-time approximation to solve the electronic Boltzmann transport equations. The predicted transport properties and lattice thermal conductivity suggest a maximum in-plane ZT of 1.18 at 1000 K with a carrier concentration of 2.37 × 1020 cm−3. Finally, we discuss further the origins of the low lattice thermal conductivity, in particular exploring the possibility of nanostructuring to lower the phonon mean free path, reduce the thermal conductivity, and further enhance the ZT. Given the experimentally-evidenced high thermal stability and the favourable band alignment found in this work, Y2Ti2O5S2 has the potential to be a promising high-temperature n-type thermoelectric

Sr2Sb2O7: a novel earth abundant oxide thermoelectric

Here we calculate the thermoelectric properties of Sr2Sb2O7 with high-level theory including hybrid DFT and MRTA electronic scattering calculations. We obtain a maximum ZT of 0.71, in excess of other state-of-the-art oxide thermoelectrics

Increased intraventricular velocities An unrecognized cause of systolic murmur in adults

AbstractObjectives. The purpose of this study was to determine the frequency, clinical features and echocardiographic characteristics of increased intraventricular velocities (IIVs) in patients referred to the echocardiography laboratory for systolic murmur.Background. A subset of patients referred to the echocardiography laboratory for evaluation of a systolic murmur have IIVs in the absence of other recognized causes of systolic murmur.Methods. We prospectively studied echocardiograms from 108 consecutive patients referred for evaluation of a systolic murmur. Clinical data were obtained from patient examinations and medical records.Results. The sole explanation for systolic murmur was IIVs in 16.7% of referred patients. Compared with those without IIVs, patients with IIVs had a higher ejection fraction (EF) (58.7 ± 7.8% vs. 51.1 ± 12.5%, p < 0.001), percent fractional shortening (42.3 ± 9.7% vs. 31.0 ± 11.4%, p < 0.0001), left ventricular (LV) mass index (181 ± 70 vs. 152 ± 48 g/m2, p = 0.046) and prevalence of hypertension (73.3% vs. 51.7%, p = 0.043) and a lower prevalence of segmental wall motion abnormalities (2.2% vs. 39.3%, p < 0.001).Conclusions. Increased intraventricular velocities are a common cause of systolic murmur in this group of patients and should be included in the differential diagnosis of systolic murmurs in adults. The association of IIVs with LV hypertrophy should be a clinical consideration when these murmurs are identified

Extended duration optically stimulated luminescence in quartz

As part of an investigation into the mechanisms underlying optically stimulated luminescence (OSL) in quartz, we have shone a number of South Australian natural quartzes over a six day measurement period. During this time the OSL signal was recorded over ten decades in time and fell six to seven decades in luminescent intensity. In particular, we observe the presence of a number of steps that appear when the luminescence is displayed in log/log form. In exploring the underlying mechanism, we review both the standard energy band gap model for quartz OSL and the alternative defect pair model and find that the latter can be applied to explain the steps in terms of a nearest neighbour extension.Owen M. Williams, Nigel A. Spooner, Barnarby W. Smith, Jillian E. Moffat

Discovery of multi-anion antiperovskites X₆NFSn₂ (X = Ca, Sr) as promising thermoelectric materials by computational screening

The thermoelectric performance of existing perovskites lags far behind that of state-of-the-art thermoelectric materials such as SnSe. Despite halide perovskites showing promising thermoelectric properties, namely, high Seebeck coefficients and ultralow thermal conductivities, their thermoelectric performance is significantly restricted by low electrical conductivities. Here, we explore new multi-anion antiperovskites X6NFSn2 (X = Ca, Sr, and Ba) via B-site anion mutation in antiperovskite and global structure searches and demonstrate their phase stability by first-principles calculations. Ca6NFSn2 and Sr6NFSn2 exhibit decent Seebeck coefficients and ultralow lattice thermal conductivities (&lt;1 W m−1 K−1). Notably, Ca6NFSn2 and Sr6NFSn2 show remarkably larger electrical conductivities compared to the halide perovskite CsSnI3. The combined superior electrical and thermal properties of Ca6NFSn2 and Sr6NFSn2 lead to high thermoelectric figures of merit (ZTs) of ∼1.9 and ∼2.3 at high temperatures. Our exploration of multi-anion antiperovskites X6NFSn2 (X = Ca, Sr) realizes the “phonon-glass, electron-crystal” concept within the antiperovskite structure