Magnetic field e ects have been a successful tool for studying carrier dynamics in organic semiconductors as the weak spin-orbit coupling in these materials gives rise to long spin relaxation times. As the spin-orbit coupling is strong in organic-inorganic hybrid perovskites, which are promising materials for photovoltaic and light-emitting applications, magnetic field e ects are expected to be negligible in these optoelectronic devices. We measured significant magneto-photocurrent, magneto-electroluminescence and magneto-photoluminescence responses in hybrid perovskite devices and thin films, where the amplitude and shape are correlated to each other through the electron-hole lifetime, which depends on the perovskite film morphology. We attribute these responses to magnetic-field-induced spin-mixing of the photogenerated electron-hole pairs with di erent g-factors-the g model. We validate this model by measuring large g (∼ 0.65) using field-induced circularly polarized photoluminescence, and electron-hole pair lifetime using picosecond pump-probe spectroscopy.T he organic-inorganic hybrid perovskites (CH 3 NH 3 PbX 3 , X = halogen; Fig. 1a) have attracted an immense interest recently as an excellent candidate for photovoltaic solar cells 1-7 . Record power conversion efficiency (PCE) of 19.3% has been achieved in optimized devices with a finely grown perovskite active layer 8 . It has been shown that the perovskites have a large absorption coefficient in the visible-near-infrared spectral range, and high charge carriers' photogeneration efficiency 9-11 ; both properties are excellent for photovoltaic applications. Interestingly, the same hybrid perovskites show photoluminescence (PL) emission ( Fig. 1b), laser action 12 and electroluminescence (EL) in lightemitting diodes 13 (LEDs). However, the underlying photophysics of the efficient charge photogeneration for photovoltaic applications, and the mechanism of radiative charge recombination that is required for LED applications are not yet clear 14,15 . In particular the perovskite layer consists of many tiny crystalline domains, where the natural disorder may encourage the formation of relatively long-lived spin-1/2 electron-hole (e-h) pairs 16 . Consequently, the generation and recombination of these spin-pair species may be influenced by a magnetic field.The magnetic field effect (MFE) technique has been a powerful tool for studying spin-dependent generation and recombination processes of spin-pair species in carbon-based semiconductor film devices 17,18 . In this technique the applied magnetic field, B, modulates the outcome physical quantity in the optoelectronic device, in the form of magneto-conductivity (MC) and magnetophotoconductivity (MPC) in organic photovoltaic cells 19 , magnetoelectroluminescence (MEL) in organic LEDs (ref. 20), and magnetophotoluminescence (MPL) in pristine films 21 . This occurs because B changes the spin sublevels character in the spin-pair manifold; which, in turn changes the inter-sublevels spin-mixing rates that consequently ...

The hybrid halide perovskites combine the low-cost processing characteristics of organic materials with the performance factors of inorganic compounds. Recently the power conversion efficiencies of perovskite photovoltaic solar cells have reached a respective value of ∼20%. The charge transport properties were indirectly approximated in these compounds because of lack of available field-effect transistors (FETs). Here we report the fabrication and room-temperature operation of FETs based on the hybrid perovskites. We obtained balanced electron and hole transport with mobilities of ∼1 cm 2 / Vs. We also found that the yield, as well as the operational and environmental stability of the fabricated transistors is limited.Inorganic perovskite materials have attracted significant research effort given their rich physical properties that includes high-temperature superconductivity, colossal magnetoresistance, ferroelectricity, diverse magnetic properties, etc. [1,2] Their structure has the general formula ABX 3 , where the cation B resides in the center of the corner sharing BX 6 octahedra, the X anions occupy the corners; whereas cation A is surrounded by eight such octahedra (see, for example, SrTiO 3 , YMnO 3 , YVO 3 , and LaMnO 3 ). The newest member of the perovskite family, namely the organic-inorganic perovskites, have recently emerged as an intriguing class of materials, which combine the low-cost processing and versatility characteristics to organic materials with the performance factors of inorganic compounds. [3,4] In particular, organo-lead halide perovskites (A + PbX 3 ), where A + is the organic cation and X denotes the halogen atom, have quickly become one of the hottest topics of research these days, in spite of the concerns related to the environmental hazard posed by the lead component. For example, the power conversion efficiency of hybrid perovskite photovoltaic (PV) solar cells has exceeded 19%, [5] and the light-emitting diodes (LEDs) based on these compounds rival the best on the market.[6] In addition, hybrid perovskite semiconductors exhibit wavelength-tunable photoluminescence (PL) emission, [7] laser action, [8] and charge carrier diffusion lengths of the order of hundreds of micrometers.[9] Surprisingly, these compounds also show interesting spin-related properties, including magneto-photocurrent, magneto-electroluminescence, and magneto-PL, in spite of their fast spin relaxation that is due to the strong spin-orbit coupling. [10,11] The hybrid perovskites based on methylammonium (where A + = CH 3 NH 3 + ) are most common, but other organic cations, such as ethylammonium CH 3 CH 2 NH 3 + or formamidinium NH 2 CH = NH 2 + have also been explored. [12,13] It has been found that the anion (X = I, Br, Cl) impacts a variety of physical properties such as the crystal quality, [14] band-gap, [15] PV solar cell efficiency, [16] exciton-binding energy [17] and the amplified spontaneous emission wavelength.[8] Mixed halide perovskites such as CH 3 NH 3 PbI 3-x Cl x , offer the possibility of ...

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TANGO1 interacts with COPII components to generate a transport carrier for export of large cargo from the endoplasmic reticulum. Raote et al. show that TANGO1 molecules assemble to form a closed ribbon structure that encircles COPII components.

Early stage lung cancer is routinely treated by lobectomy whenever clinically feasible, whereas the role of segmentectomy is controversial. The purpose of this study was to investigate the benefits of segmentectomy vs lobectomy for early stage lung cancer through a meta-analysis of published data. Eligible studies were identified from MEDLINE through February 2013. The manual selection of relevant studies was based on the summary analysis. We used published hazard ratios (HRs) if available or estimates from the published survival data. Lobectomy was chosen as the reference in all HR calculations. We compared the effect of segmentectomy and lobectomy for Stage I, Stage IA, Stage IA with tumours larger than 2 cm but smaller than 3 cm in size and Stage IA with tumours of 2 cm or smaller in 22 observational studies. The HRs of overall and cancer-specific survival indicated significant benefits of lobectomy for Stage I, Stage IA and Stage IA with tumours larger than 2 cm but smaller than 3 cm at 1.20 (95% confidence interval [CI] 1.04-1.38; P = 0.011), 1.24 (95% CI 1.08-1.42; P = 0.002) and 1.41 (95% CI 1.14-1.71; P = 0.001), respectively. For tumours 2 cm or smaller, segmentectomy provided an effect equivalent to that of lobectomy (HR 1.05; 95% CI 0.89-1.24; P = 0.550). No significant publication bias was detected in any part of the analysis. These findings should be interpreted in the context of the inherent limitations of meta-analyses of retrospective studies, including the heterogeneity of patient characteristics.

We have developed a novel, high resolution, image acquisition, and quantification approach to study a whole in-vitro heart at myofibre resolution, providing integrated 3D structural information at microscopic level without any need of tissue slicing and processing. This superior imaging approach opens up new possibilities for a systems approach towards analysing cardiac structure and function, providing rapid acquisition of quantitative microstructure of the heart in a near native state.

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Background: Patient satisfaction has become an important component of the delivery of health care in the United States.