Phonon-Metamorphosis in Ferromagnetic Manganite Films: Probing the Evolution of an Inhomogeneous State

The analysis of phonon anomalies provides valuable information about the cooperative dynamics of lattice, spin and charge degrees of freedom. Significant is the anomalous temperature dependence of the external modes observed in La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ (LSMO) films. The two external modes merge close to the ferromagnetic to paramagnetic transition at $T_C$ and, moreover, two new modes evolve in this temperature range with strong resonances at slightly higher frequencies. We propose that this observed phonon metamorphosis probes the inhomogeneous Jahn-Teller distortion, manifest on the temperature scale $T_C$. The analysis is based on the first observation of all eight phonon modes in the metallic phase of LSMO and on susceptibility measurements which identify a Griffiths-like phase.Comment: 4 pages, 4 figure

Metabolic syndrome in rural Peruvian adults living at high altitudes using different cookstoves

This study determined the prevalence of metabolic syndrome (MetS) in open fire stoves and improved cookstoves users (ICS) in the rural Peruvian Andes. Participants answered a socioeconomic questionnaire, one 24-hour food recall and underwent a physical examination. We analysed data from 385 participants, 190 (112 women and 78 men) were ICS users and 195 (123 women and 72 men) were open fire stove users. The prevalence of MetS was 21.3, 26.4% in women and 13.3% in men. We found no statistically significant association between the type of cookstove and MetS. Body mass index and altitude were important determinants of MetS. Research on cardiometabolic diseases and open fire stove use contributes to understanding the effect of household air pollution on health in high altitude populations

Improving household air, drinking water and hygiene in rural Peru : a community-randomized-controlled trial of an integrated environmental home-based intervention package to improve child health

Diarrhoea and acute lower respiratory infections are leading causes of childhood morbidity and mortality, which can be prevented by simple low-cost interventions. Integrated strategies can provide additional benefits by addressing multiple health burdens simultaneously.; We conducted a community-randomized-controlled trial in 51 rural communities in Peru to evaluate whether an environmental home-based intervention package, consisting of improved solid-fuel stoves, kitchen sinks, solar disinfection of drinking water and hygiene promotion, reduces lower respiratory infections, diarrhoeal disease and improves growth in children younger than 36 months. The attention control group received an early child stimulation programme.; We recorded 24 647 child-days of observation from 250 households in the intervention and 253 in the attention control group during 12-month follow-up. Mean diarrhoea incidence was 2.8 episodes per child-year in the intervention compared with 3.1 episodes in the control arm. This corresponds to a relative rate of 0.78 [95% confidence interval (CI): 0.58-1.05] for diarrhoea incidence and an odds ratio of 0.71 (95% CI: 0.47-1.06) for diarrhoea prevalence. No effects on acute lower respiratory infections or children's growth rates were observed.; Combined home-based environmental interventions slightly reduced childhood diarrhoea, but the confidence interval included unity. Effects on growth and respiratory outcomes were not observed, despite high user compliance of the interventions. The absent effect on respiratory health might be due to insufficient household air quality improvements of the improved stoves and additional time needed to achieve attitudinal and behaviour change when providing composite interventions

Associating ground magnetometer observations with current or voltage generators

A circuit analogy for magnetosphere‐ionosphere current systems has two extremes for drivers of ionospheric currents: ionospheric electric fields/voltages constant while current/conductivity vary—the “voltage generator”—and current constant while electric field/conductivity vary—the “current generator.” Statistical studies of ground magnetometer observations associated with dayside Transient High Latitude Current Systems (THLCS) driven by similar mechanisms find contradictory results using this paradigm: some studies associate THLCS with voltage generators, others with current generators. We argue that most of this contradiction arises from two assumptions used to interpret ground magnetometer observations: (1) measurements made at fixed position relative to the THLCS field‐aligned current and (2) negligible auroral precipitation contributions to ionospheric conductivity. We use observations and simulations to illustrate how these two assumptions substantially alter expectations for magnetic perturbations associated with either a current or a voltage generator. Our results demonstrate that before interpreting ground magnetometer observations of THLCS in the context of current/voltage generators, the location of a ground magnetometer station relative to the THLCS field‐aligned current and the location of any auroral zone conductivity enhancements need to be taken into account.Key PointsConductivity and location assumptions used to interpret ground magnetic perturbations yield conflicting resultsHigh‐latitude currents associated with voltage generators may instead be associated with current generators, and vice versaWithout better constraints on conductivity/station location relative to currents, conflicts will not be resolvedPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138366/1/jgra53632.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138366/2/jgra53632_am.pd

Silk fibroin microparticles as carriers for delivery of human recombinant bone morphogenetic protein-2 : in vitro and in vivo bioactivity

The in vitro and in vivo efficiency of fibroin microparticles as a delivery carrier for bone morphogenetic protein-2 (BMP-2) was evaluated. BMP-2 was encapsulated in silk fibroin particles that were produced by a simple and very mild processing method. The dose-response of BMP-2-loaded fibroin particles was examined in C2C12 cells, after 5 days of culture. The BMP-2 retained most of its activity as observed by the increase in alkaline phosphatase activity, which was much higher when BMP-2 was encapsulated into the particles rather than just surface-adsorbed. After 2 weeks of culture, increased mineralization was observed with BMP-2-loaded particles in comparison to soluble added growth factor. No significant cytotoxicity was detected. When implanted in a rat ectopic model, bone formation was observed by in vivo micro-computed tomography after 2 and 4 weeks postimplantation, with particles loaded with 5 or 12.5 microg BMP-2. An increase in bone density was observed over time. Histology revealed further evidence of ectopic bone formation, observed by strong alizarin red staining and osteocalcin immunostaining. Our findings show that fibroin microparticles may present an interesting option for future clinical applications in the bone tissue engineering field, and therefore, further studies have been planned.The authors acknowledge Anna Hofmann and Anna Khadem for additional help with some experiments, and Karin Brenner for animal maintenance. This work was supported by Fundacao para a Ciencia e Tecnologia (Ph.D. grant SFRH/BD/17049/2004), project ElastM (POCI/CTM/57177/2004 funded by FEDER and the Fundacao para a Ciencia e Tecnologia), Marie Curie Alea Jacta EST short-term grant (MEST-CT-2004-8104), and European STREP Project HIP-POCRATES (NMP3-CT-2003-505758). This work was carried out under the scope of the European NoE EXPERTISSUES (NMP3-CT-2004-500283)

Magnetospheric ULF waves with increasing amplitude related to solar wind dynamic pressure changes: The Time History of Events and Macroscale Interactions during Substorms (THEMIS) observations

Ultralow frequency (ULF) waves play an important role in transferring energy by buffeting the magnetosphere with solar wind pressure impulses. The amplitudes of magnetospheric ULF waves, which are induced by solar wind dynamic pressure enhancements or shocks, are thought to damp in one half a wave cycle or an entire wave cycle. We report in situ observations of solar wind dynamic pressure impulse‐induced magnetospheric ULF waves with increasing amplitudes. We found six ULF wave events induced by solar wind dynamic pressure enhancements with slow but clear wave amplitude increase. During three or four wave cycles, the amplitudes of ion velocities and electric field of these waves increased continuously by 1.3–4.4 times. Two significant events were selected to further study the characteristics of these ULF waves. We found that the wave amplitude growth is mainly contributed by the toroidal mode wave. Three possible mechanisms of causing the wave amplitude increase are discussed. First, solar wind dynamic pressure perturbations, which are observed in a duration of 20–30 min, might transfer energy to the magnetospheric ULF waves continually. Second, the wave amplitude increase in the radial electric field may be caused by superposition of two wave modes, a standing wave excited by the solar wind dynamic impulse and a propagating compressional wave directly induced by solar wind oscillations. When superposed, the two wave modes fit observations as does a calculation that superposes electric fields from two wave sources. Third, the normal of the solar wind discontinuity is at an angle to the Sun‐Earth line. Thus, the discontinuity will affect the dayside magnetopause continuously for a long time.Key PointsSix Psw enhancement‐induced ULF waves with increasing amplitudes were observedThe wave amplitude could increase four times in several wave periodsSuperposition of two wave modes could cause the wave amplitude increasePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/115986/1/jgra52015_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/115986/2/jgra52015.pd

Characterization of the binding sites of the anticancer ruthenium(III) complexes KP1019 and KP1339 on human serum albumin via competition studies

Indazolium trans-[tetrachloridobis(1H-indazole)ruthenate(III)] (KP1019) and its Na+ analogue (KP1339) are two of the most prominent non-platinum antitumor metal complexes currently undergoing clinical trials. After intravenous administration, they are known to bind to human serum albumin (HSA) in a noncovalent manner. To elucidate their HSA binding sites, displacement reactions with the established site markers warfarin and dansylglycine as well as bilirubin were monitored by spectrofluorimetry, ultrafiltration-UV-vis spectrophotometry, and/or capillary zone electrophoresis. Conditional stability constants for the binding of KP1019 and KP1339 to sites I and II of HSA were determined, indicating that both Ru(III) compounds bind to both sites with moderately strong affinity (log K (1)' = 5.3-5.8). No preference for either binding site was found, and similar results were obtained for both metal complexes, demonstrating low influence of the counter ion on the binding event