Absence of Morphotropic Phase Boundary Effects in BiFeO3-PbTiO3 Thin Films Grown via a Chemical Multilayer Deposition Method

Here, we report the unusual behaviour shown by the (BiFeO3)1-x-(PbTiO3)x (BF-xPT) films prepared using a multilayer deposition approach by chemical solution deposition method. Thin film samples of various compositions were prepared by depositing several bilayers of BF and PT precursors by varying the BF or PT layer thicknesses. X-ray diffraction showed that final samples of all compositions show mixing of the two compounds resulting in a single phase mixture, also confirmed by transmission electron microscopy. In contrast to bulk equilibrium compositions, our samples show a monoclinic (MA type) structure suggesting disappearance of morphotropic phase boundary (MPB) about x = 0.30 as observed in the bulk. This is accompanied by the lack of any enhancement of remnant polarization at MPB as shown by the ferroelectric measurements. Magnetic measurements show that the magnetization of the samples increases with increasing BF content. Significant magnetization of the samples indicates melting of spin spirals in the BF-xPT arising from random distribution of iron atoms across the film. Absence of Fe2+ ions in the films was corroborated by X-ray photoelectron spectroscopy measurements. The results illustrate that used thin film processing methodology significantly changes the structural evolution in contrast to predictions from the equilibrium phase diagram as well as modify the functional characteristics of BP-xPT system dramatically.Comment: 15 pages, 6 figure

Demonstration of the temporal matter-wave Talbot effect for trapped matter waves

We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to 10th order.Comment: 17 pages, 7 figure

Estimation of cooling rates during close-coupled gas atomization using secondary dendrite arm spacing measurement

Al-4 wt pct Cu alloy has been gas atomized using a commercial close-coupled gas-atomization system. The resulting metal powders have been sieved into six size fractions, and the SDAS has been determined using electron microscopy. Cooling rates for the powders have been estimated using a range of published conversion factors for Al-Cu alloy, with reasonable agreement being found between sources. We find that cooling rates are very low relative to those often quoted for gas-atomized powders, of the order of 10 K s for sub-38 μm powders. We believe that a number of numerical studies of gas atomization have overestimated the cooling rate during solidification, probably as a consequence of overestimating the differential velocity between the gas and the particles. From the cooling rates measured in the current study, we estimate that such velocities are unlikely to exceed 20 m s

Produção de clamidósporos de Pochonia chlamydosporia em diferentes substratos

Clamidósporos são estruturas de sobrevivência do fungo nematófago Pochonia chlamydosporia. Objetivou-se, com este trabalho, avaliar diferentes substratos, teores de água e formas de inóculo para a produção in vitro de clamidósporos de P. chlamydosporia. Inicialmente, testaram-se os substratos grãos de milho triturado, grãos de arroz e casca de café e os tipos de inóculo meio líquido concentrado ou diluído (1:40) e discos de cultura, colonizados por P. chlamydosporia. Posteriormente, testou-se o substrato grãos de milho triturado suplementado ou não com caldo de batata com os inóculos do fungo nas formas de discos de micélio ou suspensão aquosa. As maiores produções de clamidósporos g-1 de substrato foram obtidas nos substratos grãos de milho triturado e casca de café, e as melhores formas de inóculo foram meio líquido diluído (1:40) e discos de micélio. A suplementação do substrato grãos de milho triturado com caldo de batata não aumentou a produção de clamidósporos do fungo e a melhor forma de inóculo do fungo foi a de discos de micélio. Além disso, testaram-se os substratos canjica, grãos de arroz, casca de café e fibra de coco, umedecidos com diferentes quantidades de água; o substrato casca de café umedecido por diferentes períodos; a casca de café enriquecida ou não com sacarose e farinha de arroz e o substrato grãos de arroz esterilizado no forno micro-ondas com diferentes quantidades de água. Apenas o substrato grãos de arroz, em todas as quantidades de água testadas, apresentou maior produção de clamidósporos. Não houve diferença na produção de clamidósporos no substrato casca de café umedecido por diferentes períodos e apenas quando a casca de café foi enriquecida com farinha de arroz, apresentou maior média de clamidósporos g-1 de substrato. Todos os tratamentos apresentaram grande produção de clamidósporos g-1 quando o substrato utilizado foi o de grãos de arroz tratados no forno de micro-ondas. O melhor meio de cultivo de P. chlamydosporia para a produção de clamidósporos foi o substrato contendo grãos de arroz.Chlamydospores are survival structures of the nematophagous fungus Pochonia chlamydosporia. The objective of this study was to evaluate different substrates, different contents of water and kinds of inoculum for the production of Pochonia chlamydosporia chlamydospores. The substrates evaluated were: milled maize, rice grains and coffee husk; all of them were inoculated with disks of culture, concentrated liquid media or diluted liquid media (1:40) colonized by P. chlamydosporia. Besides, the substrates milled maize, supplemented or not with potato broth, and inoculated with fungus disks or aqueous suspension were evaluated. Milled maize and coffee husk were the best substrates for chlamydospores production. The best inoculum kinds were disks of culture and diluted liquid media (1:40) colonized by P. chlamydosporia. The supplementation of milled maize with potato broth did not improve the production of chlamydospores, and the best inoculum form was disks of fungus. Moreover, it was also studied the substrates rice grains, coffee husk and coconut fibers with different rates of water; the substrate coffee husk moistened by different periods; the supplementation of coffee husk with rice flour or dextrose; and the substrate grains of rice sterilized in microwave oven with different rates of water. The substrate grains of rice, in all of the amounts of water tested showed increase in production of chlamydospores. There was no difference in the chlamydospores production of the coffee husk substrate, when moistened by different periods of time and only when it was supplemented with rice flour it showed higher mean of clamydospores per gram of substrate. All treatments evaluated showed higher production of chlamydospores in the substrate grains of rice treated in the microwave oven. The best substrate for the production of chlamydospores of P. chlamydosporia was the rice grains

COVAD survey 2 long-term outcomes: unmet need and protocol

Vaccine hesitancy is considered a major barrier to achieving herd immunity against COVID-19. While multiple alternative and synergistic approaches including heterologous vaccination, booster doses, and antiviral drugs have been developed, equitable vaccine uptake remains the foremost strategy to manage pandemic. Although none of the currently approved vaccines are live-attenuated, several reports of disease flares, waning protection, and acute-onset syndromes have emerged as short-term adverse events after vaccination. Hence, scientific literature falls short when discussing potential long-term effects in vulnerable cohorts. The COVAD-2 survey follows on from the baseline COVAD-1 survey with the aim to collect patient-reported data on the long-term safety and tolerability of COVID-19 vaccines in immune modulation. The e-survey has been extensively pilot-tested and validated with translations into multiple languages. Anticipated results will help improve vaccination efforts and reduce the imminent risks of COVID-19 infection, especially in understudied vulnerable groups

Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018

Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe

Strange anti-particle to particle ratios at mid-rapidity in sqrt(s_NN)= 130 GeV Au+Au Collisions

Values of the ratios in the mid-rapidity yields of anti-Lambda/Lambda = 0.71 +/- 0.01(stat.) +/- 0.04(sys.), anti-Xi+/Xi- = 0.83 +/- 0.04(stat.) +/- 0.05 (sys.), anti-Omega+/Omega- = 0.95 +/- 0.15(stat) +/- 0.05(sys.) and K+/K- 1.092 +/- 0.023(combined) were obtained in central sqrt(s_NN) = 130 GeV Au+Au collisions using the STAR detector. The ratios indicate that a fraction of the net-baryon number from the initial system is present in the excess of hyperons over anti-hyperons at mid-rapidity. The trend in the progression of the baryon ratios, with increasing strange quark content, is similar to that observed in heavy-ion collisions at lower energies. The value of these ratios may be related to the charged kaon ratio in the framework of simple quark-counting and thermal models.Comment: 6 pages, 3 figures, revtex4, now accepted by Physics Letters B. All figures improved for clarity, fig. 2 now has kaon ratio separated by technique, fig. 3 now has additional other RHIC data points. Minor clarifications in text in response to referee comments. Updated ref