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Recently, a new class of quantum magnets, the so-called breathing pyrochlore spin systems, have attracted much attention due to their potential to host exotic emergent phenomena. Here, we present magnetometry, heat capacity, thermal conductivity, muon-spin relaxation, and polarized inelastic neutron scattering measurements performed on high-quality single crystal samples of the breathing pyrochlore compound Ba3Yb2Zn5O11. We interpret these results using a simplified toy model and provide insight into the low-energy physics of this system beyond the single tetrahedron physics proposed previously.

We report high-resolution dilatometry on high-quality single crystals of NiTiO3 grown by means of the optical floating-zone technique. The anisotropic magnetic phase diagram is constructed from thermal expansion and magnetostriction studies up toB=15 T and magnetization studies in static (15-T) and pulsed (60-T) magnetic fields. Our data allow us to quantitatively study magnetoelastic coupling and to determine uniaxial pressure dependencies. While the entropy changes are found to be of magnetic nature, Grüneisen analysis implies only one relevant energy scale in the whole low-temperature regime. Thereby, our data suggest that the observed structural changes due to magnetoelastic coupling and previously reported magnetodielectric coupling [L. Balhorn, J. Hazi, M. C. Kemei, and R. Seshadri, Phys. Rev. B93, 104404(2016)] are driven by the same magnetic degrees of freedom that lead to long-range magnetic order in NiTiO3.

Mycobacterium chlorophenolicum is a nontuberculous mycobacterium that has previously been characterized as nonpathogenic. We describe a 44 year-old patient with a history of deceased donor renal transplant on sirolimus who was found to meet criteria for both sirolimus-associated pneumonitis and secondary infection with Mycobacterium chlorophenolicum. In addition to describing a new infection with a generally nonpathogenic organism, we believe this case could generate new hypotheses regarding nontuberculous mycobacteria and the pathogenesis of sirolimus-associated pneumonitis.

We report an optical fiber based spectral response measurement system for multijunction solar cells. We have also fabricated single junction GaAs cells on GaAS and Ge substrates and measured lighted I-V characteristics. Preliminary quantum efficiency measurements on these devices are also presented. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/22007

Diffuse intense lung uptake of TI-201 chloride without abnormal Ga-67 citrate in a case of cytomegalovirus pneumonitis in a patient with AIDS is presented. An autopsy performed within 4 days of imaging revealed no pulmonary pathology other than diffuse cytomegalovirus infection with abundant histiocytes and inclusion bodies and pulmonary congestive heart failure. Among the various mechanisms of TI-201 accumulation, active transport through Na-K ATPase appears to be predominant in this case, as suggested by innumerable histiocytes. It is the authors' experience that positive TI-201 uptake without abnormal Ga-67 accumulation is highly specific for pulmonary Kaposi sarcoma. The presence of such discrepancy between TI-201 and Ga-67 uptake in AIDS patients decreases the specificity of a TI-201 positive/Ga-67 negative lesion for pulmonary Kaposi sarcoma, especially with the rising incidence of both cytomegalovirus and Kaposi sarcoma in AIDS patients.

We studied the magnetic excitations in the quasi-one-dimensional (q-1D) ladder subsystem of Sr14-xCaxCu24O41 (SCCO) using Cu L-3-edge resonant inelastic X-ray scattering (RIXS). By comparing momentum-resolved RIXS spectra with high (x = 12.2) and without (x = 0) Ca content, we track the evolution of the magnetic excitations from collective two-triplon (2 T) excitations (x = 0) to weakly-dispersive gapped modes at an energy of 280 meV (x = 12.2). Density matrix renormalization group (DMRG) calculations of the RIXS response in the doped ladders suggest that the flat magnetic dispersion and damped excitation profile observed at x = 12.2 originates from enhanced hole localization. This interpretation is supported by polarization-dependent RIXS measurements, where we disentangle the spin-conserving Delta S = 0 scattering from the predominant Delta S = 1 spin-flip signal in the RIXS spectra. The results show that the low-energy weight in the Delta S = 0 channel is depleted when Sr is replaced by Ca, consistent with a reduced carrier mobility. Our results demonstrate that off-ladder impurities can affect both the low-energy magnetic excitations and superconducting correlations in the CuO4 plaquettes. Finally, our study characterizes the magnetic and charge fluctuations in the phase from which superconductivity emerges in SCCO at elevated pressures.