Microbiota is essential for social development in the mouse

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50-GHz Repetition Gain Switching Using A Cavity-enhanced DFB Laser Assisted By Optical Injection Locking

We demonstrate pulse generation at a repetition rate of 50 GHz by gain switching an injection-locked distributed feedback (DFB) laser with large modulation bandwidth (BW). The small-signal BW of the DFB laser was extended from an intrinsic BW of 30 GHz to 52 GHz due to the joint effects of photon-photon resonance (PPR) and detuned-loading, which exploits the frequency-dependent cavity loss to enhance the effective differential gain and thereby the relaxation oscillation frequency. The results show that PPR and detuned-loading effects can also be utilized to improve large signal gain-switching, despite the dynamic changes of the detuned loading condition due to the large signal chirp. By modulating the laser with 50-GHz RF signals, we obtained 50-GHz repetition rate pulses from the gain-switched laser, confirming that the BW enhancement effects are still valid for large-signal modulation. After that, we optically injection lock the gain-switched laser with strong external seeding light, which suppresses the chirp and creates frequency tones with 50 GHz spacing. The optical injection locking (OIL) further improves the large-signal BW, resulting in narrower pulse width. The spectrum of the gain-switched OIL directly modulated laser (OIL-DML) showed three sideband peaks above 70% from the peak (full width half maximum of 130 GHz), and a pulse width of 9.5 ps (6.2 ps after deconvolution) was obtained. The results indicate that the pulse could be compressed to 2.4 ps, assuming linear chirp

Dynamical Mean Field Theory of the Antiferromagnetic Metal to Antiferromagnetic Insulator Transition

We study the antiferromagnetic metal to antiferromagnetic insulator using dynamical mean field theory and exact diagonalization methods. We find two qualitatively different behaviors depending on the degree of magnetic correlations. For strong correlations combined with magnetic frustration, the transition can be described in terms of a renormalized slater theory, with a continuous gap closure driven by the magnetism but strongly renormalized by correlations. For weak magnetic correlations, the transition is weakly first order.Comment: 4 pages, uses epsfig,4 figures,notational errors rectifie

Magnetic Phase Diagram and Metal-Insulator Transition of NiS2-xSex

Magnetic phase diagram of NiS2-xSex has been reexamined by systematic studies of electrical resistivity, uniform magnetic susceptibility and neutron diffraction using single crystals grown by a chemical transport method. The electrical resistivity and the uniform magnetic susceptibility exhibit the same feature of temperature dependence over a wide Se concentration. A distinct first order metal-insulator (M-I) transition accompanied by a volume change was observed only in the antiferromagnetic ordered phase for 0.50<x<0.59. In this region, the M-I transition makes substantial effects to the thermal evolution of staggered moments. In the paramagnetic phase, the M-I transition becomes broad; both the electrical resistivity and the uniform magnetic susceptibility exhibit a broad maximum around the temperatures on the M-I transition-line extrapolated to the paramagnetic phase.Comment: 6 pages, 8 figures, corrected EPS fil

Local high relief at the southern margin of the Andean plateau by 9 Ma: evidence from ignimbritic valley fills and river incision

A valley-filling ignimbrite re-exposed through subsequent river incision at the southern margin of the Andean (Puna) plateau preserves pristine geological evidence of pre-late Miocene paleotopography in the northwestern Argentine Andes. Our new 40Ar/39Ar dating of the Las Papas ignimbrites yields a plateau age of 9.24 ± 0.03 Ma, indicating valley relief and orographic-barrier conditions comparable to the present-day. A later infill of Plio- Pleistocene coarse conglomerates has been linked to wetter conditions, but resulted in no additional net incision of the Las Papas valley, considering that the base of the ignimbrite remains unexposed in the valley bottom. Our observations indicate that at least 550 m of local plateau margin relief (and likely >2 km) existed by 9 Ma at the southern Puna margin, which likely increased the efficiency of the orographic barrier to rainfall along the eastern and southeastern flanks of the Puna and caused aridity in the plateau interior.Fil: Montero Lopez, Maria Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Strecker, Manfred R.. Universitat Potsdam; AlemaniaFil: Schildgen, Taylor F.. Universitat Potsdam; AlemaniaFil: Hongn, Fernando Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Guzman, Silvina Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Bookhagen, Bodo. Universitat Potsdam; AlemaniaFil: Sudo, Masafumi. Universitat Potsdam; Alemani

Multi-model simulations of the impact of international shipping on Atmospheric Chemistry and Climate in 2000 and 2030

The global impact of shipping on atmospheric chemistry and radiative forcing, as well as the associated uncertainties, have been quantified using an ensemble of ten state-of-the-art atmospheric chemistry models and a predefined set of emission data. The analysis is performed for present-day conditions ( year 2000) and for two future ship emission scenarios. In one scenario ship emissions stabilize at 2000 levels; in the other ship emissions increase with a constant annual growth rate of 2.2% up to 2030 ( termed the "Constant Growth Scenario" (CGS)). Most other anthropogenic emissions follow the IPCC ( Intergovernmental Panel on Climate Change) SRES ( Special Report on Emission Scenarios) A2 scenario, while biomass burning and natural emissions remain at year 2000 levels. An intercomparison of the model results with observations over the Northern Hemisphere (25 degrees - 60 degrees N) oceanic regions in the lower troposphere showed that the models are capable to reproduce ozone (O-3) and nitrogen oxides (NOx= NO+ NO2) reasonably well, whereas sulphur dioxide (SO2) in the marine boundary layer is significantly underestimated. The most pronounced changes in annual mean tropospheric NO2 and sulphate columns are simulated over the Baltic and North Seas. Other significant changes occur over the North Atlantic, the Gulf of Mexico and along the main shipping lane from Europe to Asia, across the Red and Arabian Seas. Maximum contributions from shipping to annual mean near-surface O-3 are found over the North Atlantic ( 5 - 6 ppbv in 2000; up to 8 ppbv in 2030). Ship contributions to tropospheric O3 columns over the North Atlantic and Indian Oceans reach 1 DU in 2000 and up to 1.8 DU in 2030. Tropospheric O-3 forcings due to shipping are 9.8 +/- 2.0 mW/m(2) in 2000 and 13.6 +/- 2.3 mW/m(2) in 2030. Whilst increasing O-3, ship NOx simultaneously enhances hydroxyl radicals over the remote ocean, reducing the global methane lifetime by 0.13 yr in 2000, and by up to 0.17 yr in 2030, introducing a negative radiative forcing. The models show future increases in NOx and O-3 burden which scale almost linearly with increases in NOx emission totals. Increasing emissions from shipping would significantly counteract the benefits derived from reducing SO2 emissions from all other anthropogenic sources under the A2 scenario over the continents, for example in Europe. Globally, shipping contributes 3% to increases in O-3 burden between 2000 and 2030, and 4.5% to increases in sulphate under A2/CGS. However, if future ground based emissions follow a more stringent scenario, the relative importance of ship emissions will increase. Inter-model differences in the simulated O-3 contributions from ships are significantly smaller than estimated uncertainties stemming from the ship emission inventory, mainly the ship emission totals, the distribution of the emissions over the globe, and the neglect of ship plume dispersion

Development of a new common tobacco cultivar resistant to mosaic virus in Brazil

A cultivar CSC 300 é a mais recente variedade de fumo tipo "comum" disponível para plantio em áreas infestadas pelo TMV (Vírus do Mosaico do Fumo). A nova cultivar, imune ao TMV, foi obtida pelo método do retrocruzamento, utilizando-se, inicialmente, as cultivares CO-D (Palotina) como pai recorrente, e duas cultivares de fumo Burley (Ky-14 e Ky- 12) como doadoras dos genes "NN", responsáveis pelo caráter imunidade (hipersensibilidado das células infectadas). A nova cultivar foi superior à comercial tanto em produtividade quanto em qualidade das folhas curadas, possuindo características fenotípicas bastante somelhantes à cultivar CO-D. Os testes envolvendo painéis de fumaça foram muito bons alcançando grande concordância com os padrões organolépticos esperados dentro do tipo de fumo "Galpão Comum". Esta nova cultivar foi entregue aos produtores de fumo para plantio já na safra-87, através do "Centro de Pesquisas e Melhoramento Genético do Fumo" da Souza CruzA new "Galpão Comum" tobacco variety carrying resistance to the Tobacco Mosaic Virus - TMV, was developed through the backcross metbod. The initial crosses employed the most commercial CO-D (Palotina) variety and the donor parente Ky- 14 and Ky-12 that are Burley varieties and also belong to the air cured group. These donor parents possess the hypersensitivity (HS) type of resistance to TMV. The resultant TMV immune variety, named CSC 300, was higher in yield and had more desirable cured leaves, according to the amount of tanish leaves (L) and quality grade 2 produced. The phenotypic characteristics of this new variety were considered quite similar to the recurrent parent (CO-D/Palotina). The smoking panels tests were very good and had a strong agreement with the normal characteristics for the "Galpão Comum" favorite type. This new variety was developed to be given to the formers, for the 1986/87 crop season, by the Genetic and Breeding Research Center of Souza Cruz

Testing theories of temporal inferences: Evidence from child language

Sentences involving past tense verbs, such as “My dogs were on the carpet”, tend to give rise to the inference that the corresponding present tense version, “My dogs are on the carpet”, is false. This inference is often referred to as a cessation or temporal inference, and is generally analyzed as a type of implicature. There are two main proposals for capturing this asymmetry: one assumes a difference in informativity between the past and present counterparts (Altshuler & Schwarzschild 2013), while the other proposes a structural difference between the two (Thomas 2012). The two approaches are similar in terms of empirical coverage, but differ in their predictions for language acquisition. Using a novel animated picture selection paradigm, we investigated these predictions. Specifically, we compared the performance of a group of 4–6-year-old children and a group of adults on temporal inferences, scalar implicatures arising from “some”, and inferences of adverbial modifiers under negation. The results revealed that overall, children computed all three inferences at a lower rate than adult controls; however they were more adult-like on temporal inferences and inferences of adverbial modifiers than on scalar implicatures. We discuss the implications of the findings, both for a developmental alternatives-based hypothesis (e.g., Barner et al. 2011; Singh et al. 2016; Tieu et al. 2016; 2018), as well as theories of temporal inferences, arguing that the finding that children were more (and equally) adult-like on temporal inferences and adverbial modifiers supports a structural theory of temporal inferences along the lines of Thomas (2012)

cAMP-Signalling Regulates Gametocyte-Infected Erythrocyte Deformability Required for Malaria Parasite Transmission.

Blocking Plasmodium falciparum transmission to mosquitoes has been designated a strategic objective in the global agenda of malaria elimination. Transmission is ensured by gametocyte-infected erythrocytes (GIE) that sequester in the bone marrow and at maturation are released into peripheral blood from where they are taken up during a mosquito blood meal. Release into the blood circulation is accompanied by an increase in GIE deformability that allows them to pass through the spleen. Here, we used a microsphere matrix to mimic splenic filtration and investigated the role of cAMP-signalling in regulating GIE deformability. We demonstrated that mature GIE deformability is dependent on reduced cAMP-signalling and on increased phosphodiesterase expression in stage V gametocytes, and that parasite cAMP-dependent kinase activity contributes to the stiffness of immature gametocytes. Importantly, pharmacological agents that raise cAMP levels in transmissible stage V gametocytes render them less deformable and hence less likely to circulate through the spleen. Therefore, phosphodiesterase inhibitors that raise cAMP levels in P. falciparum infected erythrocytes, such as sildenafil, represent new candidate drugs to block transmission of malaria parasites

White Matter Microstructural Changes and Episodic Memory Disturbances in Late-Onset Bipolar Disorder

Background: Bipolar disorder (BD) has been associated with distributed network disruption, but little is known on how different clinical subtypes, particularly those with an earlier and later onset of disease, are related to connectivity changes in white matter (WM) tracts.Methods: Diffusion tensor imaging (DTI) and volumetric measures were carried out in early-onset bipolar patients [(EOD) (n = 16)], late-onset bipolar disorder [(LOD)(n = 14)] and healthy controls (n = 32). We also computed ROI analysis of gray matter (GM) and white matter (WM) volumes using the regions with significant group differences in the DTI parameters. Cognitive and behavior measurements were analyzed between groups.Results: Lower fraction of anisotropy (FA) in the right hemisphere comprising anterior thalamic radiation, fornix, posterior cingulate, internal capsule, splenium of corpus callosum was observed in the LOD in comparison with EOD; additionally, lower FA was also found in the LOD in comparison with healthy controls, mostly in the right hemisphere and comprising fibers of the splenium of the corpus callosum, cingulum, superior frontal gyrus and posterior thalamic radiation; LOD also showed worse episodic memory performance than EOD; no statistical significant differences between mood symptoms, WM and GM volumes were found between BD groups.Conclusion: Even after correcting for age differences, LOD was associated with more extensive WM microstructural changes and worse episodic memory performance than EOD; these findings suggest that changes in the WM fiber integrity may be associated with a later presentation of BD, possibly due to mechanisms other than neuroprogression. However, these findings deserve replication in larger, prospective, studies