The long-term behavioral and neurochemical effects of 24
h maternal separation were assessed in rats of both genders. Maternal deprivation was applied at the age of 9 days, whereas consequences were ...assessed 3 months later. Deprived rats (irrespective of gender) showed a considerable growth retardation that disappeared till adulthood. The plus-maze performance of control and deprived males did not differ under normal conditions, but deprived males showed more anxiety when the test was applied shortly after stress exposure. CRH mRNA expression in the amygdala, but not in the hypothalamus, was more intense in deprived as compared with control males. Deprived females were not affected. These data suggest that (i) the maternal deprivation induced changes are larger in males than in females, (ii) maternal deprivation induces a latent behavioral disposition towards anxiety that is precipitated by acute stressors, and (iii) the changes noticed in amygdalar CRH expression may serve as mechanisms for the behavioral changes noticed.
We propose a single electro-optic amplitude modulator to modulate both the intensity and the phase of the light of a diode laser to produce frequency-chirped light pulses in the nanosecond time ...range. The two-in-one property of the Mach–Zehnder type electro-optic amplitude modulator is used to create a specific device available for experiments with cooled atoms. The phase induced in each optical path of the Mach–Zehnder interferometer and the phase-to-intensity modulation ratio, the intrinsic chirp parameter of the device is determined by generating high order optical harmonics.
A Hot Jupiter in a Nearly Polar Orbit Addison, Brett C.; Tinney, Chris G.; Wright, Duncan J. ...
Proceedings of the International Astronomical Union,
06/2013, Letnik:
8, Številka:
S299
Journal Article
Recenzirano
Odprti dostop
We measured the spin-orbit misalignment for WASP-79b, a transiting hot Jupiter from the WASP survey. Using the Rossiter-McLaughlin effect during the transit event, we determined the sky-projected ...obliquity to be λ = −106+10−8○. This result indicates that the planet is in a nearly polar orbit.
This paper analyzes the impact of e-commerce on markets where established firms face competition from Internet-based entrants with focused offerings. In particular, we study the retail brokerage ...sector where the growth of online brokerages and the availability of alternate sources of information and research services have challenged the dominance of traditional brokerages. We develop a stylized game-theoretic model to analyze the impact of competition between an incumbent full-service brokerage firm with a bundled offering of research services and trade execution and an online entrant offering just trade execution. We find that as consumers willingness to pay for research declines, the incumbent finds it optimal to unbundle its offering when competing with the online entrant. We also find that the online entrant chooses a lower quality of trade execution when faced with direct competition from the incumbents unbundled offering. The analytical model motivates a unique field experiment placing actual simultaneous trades with traditional full-service and online brokers, to compare order handling practices and the quality of trade execution. In keeping with our analytical results, our empirical findings show a significant difference in the quality of execution between online brokerages and their full-service counterparts. We discuss the relevance of our findings for quality differentiation, price convergence, and profit decline in a variety of markets where traditional incumbents are faced with changes in the competitive landscape as a result of e-commerce.
Background: Chronic urticaria has been described in patients with Helicobacter pylori infection. We studied the titer of IgG and IgA type antibodies against H. pylori in patients with and without ...urticaria of unknown etiology. We also investigated the prevalence of antibodies against H. pylori‐associated lipoprotein 20 (lpp20) in patients with and without chronic urticaria.
Methods: The concentration of anti‐H. pylori antibodies (IgG and IgA) was determined by the RIDA test. The level of anti‐lpp20 antibodies was determined by Western blot using various H. pylori antigens (from 19 to 120 kDa).
Results: Patients with chronic urticaria and H. pylori infection (subgroup 1, n = 33) had high IgG and IgA titers whereas all patients with chronic urticaria and without H. pylori infection (subgroup 2, n = 23) were seronegative (P = 0.0128 for IgG and P = 0.003 for IgA). Titers in subgroup 1 did not differ significantly from a control group (n = 33) with severe H. pylori‐associated gastritis without urticaria. The prevalence of the anti‐lpp20 antibodies was significantly higher in subgroup 1 compared to the control group (93.9 vs 21.2%, P < 0.0001 for IgG, and 46.1 vs 6.3%, P < 0.0029 for IgA).
Conclusions: We suggest that IgG and IgA antibodies to H. pylori‐associated lpp20 may play role in the pathogenesis of chronic urticaria.
The main goal of this study was to evaluate the possible effect of whole-body magnetic field (MF) exposure on the steroidogenic capacity of Leydig cells in vitro. In four separate experiments, male ...CFLP mice were exposed to sinusoidal 50-Hz, 100-microT MF. The duration of exposure was 23.5 h/day over a period of 14 days. At the end of the exposure, interstitial (Leydig) cells were isolated from the testicles of the sham-exposed and exposed animals. The cells were cultured for 48 h in the presence or absence of 1, 10, or 100 mIU/ml human chorionic gonadotropin (hCG). The luteinizing hormone (LH) analog hCG was used to check the testosterone (T) response of the sham-exposed controls and to evaluate the possible effect of the whole-body MF exposure on the steroidogenic capacity of Leydig cells in vitro. Testosterone content of the culture media and blood sera was measured by radioimmunoassay (RIA). In the cultures obtained from MF-exposed animals, the hCG-stimulated T response was significantly higher (p < 0.01) compared with the sham-exposed controls, while the basal T production of cells and the level of serum T remained unaltered. No MF exposure-related histopathological alterations were found in testicles, epididymes, adrenals, prostates, and pituitary glands. The MF exposure did not affect the animal growth rate and the observed hematologic and serum chemical variables. Our results indicate a presumably direct effect of whole-body MF exposure on the hCG-stimulated steroidogenic response of mouse Leydig cells.
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