Present experimental and astrophysical limits do not exclude that the neutron (
n
) oscillation into mirror neutron (
n
′
), a sterile state exactly degenerate in mass with the neutron, can be a very ...fast process, in fact faster than the neutron decay itself, in which case it would have very interesting implications in cosmology and astrophysics. This process is sensitive to the magnetic field. Namely, if the mirror magnetic field
B
′
exists at the Earth,
n
-
n
′
oscillation probability can be suppressed or resonantly amplified by the applied magnetic field
B
, depending on its strength and on the angle
β
between
B
and
B
′
. We present the results of ultra-cold neutron storage measurements aiming to check the anomalies observed in previous experiments which could be a signal for
n
-
n
′
oscillation in the presence of mirror magnetic field
B
′
∼
0.1
G. From the analysis of the experimental data new lower limits on
n
-
n
′
oscillation time as a function of
B
′
were obtained, assuming that the mirror magnetic field is constant in time:
τ
n
n
′
>
17
s (95 % C.L.) for any
B
′
between 0.08 and 0.17 G, and
τ
n
n
′
/
cos
β
>
27
s (95 % C.L.) for any
B
′
in the interval (
0.06
÷
0.25
) G.
Volcanic activity occurring in tropical moist atmospheres can promote deep convection and trigger volcanic thunderstorms. These phenomena, however, are rarely observed to last continuously for more ...than a day and so insights into the dynamics, microphysics and electrification processes are limited. Here we present a multidisciplinary study on an extreme case, where volcanically-triggered deep convection lasted for six days. We show that this unprecedented event was caused and sustained by phreatomagmatic activity at Anak Krakatau volcano, Indonesia during 22-28 December 2018. Our modelling suggests an ice mass flow rate of ~5 × 10
kg/s for the initial explosive eruption associated with a flank collapse. Following the flank collapse, a deep convective cloud column formed over the volcano and acted as a 'volcanic freezer' containing ~3 × 10
kg of ice on average with maxima reaching ~10
kg. Our satellite analyses reveal that the convective anvil cloud, reaching 16-18 km above sea level, was ice-rich and ash-poor. Cloud-top temperatures hovered around -80 °C and ice particles produced in the anvil were notably small (effective radii ~20 µm). Our analyses indicate that vigorous updrafts (>50 m/s) and prodigious ice production explain the impressive number of lightning flashes (~100,000) recorded near the volcano from 22 to 28 December 2018. Our results, together with the unique dataset we have compiled, show that lightning flash rates were strongly correlated (R = 0.77) with satellite-derived plume heights for this event.
The thermal structure of tropical cyclones (TCs) in different ocean basins is studied using global positioning system (GPS) radio occultation (RO) measurements co-located with TCs' best tracks. The ...objective of this work is to understand the mutual influence of TCs and atmospheric parameters in different regions. We selected more than 20 000 GPS RO profiles co-located with TCs in a time window of 6 h and space window of 600 km from the TC center in the period 2001–2012 and classified them by intensity of the cyclone and by ocean basin. The results show that TCs have different characteristics depending on the basin, which affects the cloud top altitude and the TC thermal structure which usually shows a negative temperature anomaly near the cloud top altitude. In the Northern Hemisphere ocean basins, the temperature anomaly becomes positive above the cloud top while in the Southern Hemisphere ocean basins it stays negative up to about 25 km in altitude. Furthermore, in the Southern Hemisphere the storms reach higher cloud top altitudes than in the Northern Hemisphere ocean basins, indicating that possible overshootings overpass the climatological tropopause more deeply at extratropical latitudes. The comparison of the TC thermal structure with the respective monthly mean tropopause altitude allows for a detailed analysis of the probability for possible overshooting. While the co-locations between GPS ROs and TC tracks are well distributed in all the ocean basins, conditions for possible overshootings are found to be more frequent in the Southern Hemisphere basins and in the northern Indian Ocean basin. However, the number of possible overshootings for high intensity storms (i.e., TC categories 1–5) is the highest in the western Pacific Ocean basin.
Thermal structure associated with deep convective clouds is investigated using Global Positioning System (GPS) radio occultation measurements. GPS data are insensitive to the presence of clouds, and ...provide high vertical resolution and high accuracy measurements to identify associated temperature behavior. Deep convective systems are identified using International Satellite Cloud Climatology Project (ISCCP) satellite data, and cloud tops are accurately measured using Cloud-Aerosol Lidar with Orthogonal Polarization (CALIPSO) lidar observations; we focus on 53 cases of near-coincident GPS occultations with CALIPSO profiles over deep convection. Results show a sharp spike in GPS bending angle highly correlated to the top of the clouds, corresponding to anomalously cold temperatures within the clouds. Above the clouds the temperatures return to background conditions, and there is a strong inversion at cloud top. For cloud tops below 14 km, the temperature lapse rate within the cloud often approaches a moist adiabat, consistent with rapid undiluted ascent within the convective systems.
The inhibition of GSK3 is required for the stimulation of glycogen and protein synthesis by insulin and the specification of cell fate during development. Here, we demonstrate that the ...insulin-induced inhibition of GSK3 and its unique substrate specificity are explained by the existence of a phosphate binding site in which Arg-96 is critical. Thus, mutation of Arg-96 abolishes the phosphorylation of “primed” glycogen synthase as well as inhibition by PKB-mediated phosphorylation of Ser-9. Hence, the phosphorylated N terminus acts as a pseudosubstrate, occupying the same phosphate binding site used by primed substrates. Significantly, this mutation does not affect phosphorylation of “nonprimed” substrates in the Wnt-signaling pathway (Axin and β-catenin), suggesting new approaches to design more selective GSK3 inhibitors for the treatment of diabetes.
An adjusting‐delay procedure was used to study the choices of pigeons and rats when both delay and amount of reinforcement were varied. In different conditions, the choice alternatives included one ...versus two reinforcers, one versus three reinforcers, and three versus two reinforcers. The delay to one alternative (the standard alternative) was kept constant in a condition, and the delay to the other (the adjusting alternative) was increased or decreased many times a session so as to estimate an indifference point—a delay at which the two alternatives were chosen about equally often. Indifference functions were constructed by plotting the adjusting delay as a function of the standard delay for each pair of reinforcer amounts. The experiments were designed to test the prediction of a hyperbolic decay equation that the slopes of the indifference functions should increase as the ratio of the two reinforcer amounts increased. Consistent with the hyperbolic equation, the slopes of the indifference functions depended on the ratios of the two reinforcer amounts for both pigeons and rats. These results were not compatible with an exponential decay equation, which predicts slopes of 1 regardless of the reinforcer amounts. Combined with other data, these findings provide further evidence that delay discounting is well described by a hyperbolic equation for both species, but not by an exponential equation. Quantitative differences in the y‐intercepts of the indifference functions from the two species suggested that the rate at which reinforcer strength decreases with increasing delay may be four or five times slower for rats than for pigeons.
There are many factors which make canine cancer like cancer in humans. The occurrence of spontaneous mammary tumors in pet dogs, tumor genetics, molecular targets and exposure to the same ...environmental risk factors are among these factors. Therefore, the study of canine cancer can provide useful information to the oncology field. This study aimed to establish and characterize a panel of primary mixed cell cultures obtained from spontaneous canine mammary tumors. Eight established cell cultures obtained from one normal mammary gland, one complex adenoma, one mixed adenoma, two complex carcinomas and two mixed carcinomas were analyzed. The gene expression levels of classic molecular cancer players such as fibroblast growth factor receptor (FGFR) 2, breast cancer (BRCA) 1, BRCA2 and estrogen receptor (ESR) 1 were evaluated. For the first time, three orphan nuclear receptors, estrogen-related receptors (ERRs) α, β and γ were studied in canine mammary cancer. The highest expression level of ERRα was observed in complex carcinoma-derived cell culture, while the highest levels of ERRβ and γ were observed in cells derived from a mixed carcinoma. Meanwhile, complex carcinomas presented the highest levels of expression of ESR1, BRCA1 and FGFR2 among all samples. BRCA2 was found exclusively in complex adenoma. The transcription factor GATA3 had its highest levels in mixed carcinoma samples and its lowest levels in complex adenoma. Proliferation assays were also performed to evaluate the mixed cell cultures response to ER ligands, genistein and DES, both in normoxia and hypoxic conditions. Our results demonstrate that morphological and functional studies of primary mixed cell cultures derived from spontaneous canine mammary tumors are possible and provide valuable tool for the study of various stages of mammary cancer development.
AIMS: This study aimed to investigate the prevalence of Simkania negevensis in the chlorinated water of spa swimming pools and domestic network systems. METHODS AND RESULTS: A total of 10 and 36 ...samples were collected from two domestic water supplies and four spa facilities, respectively. Simkania negevensis was isolated in Acanthamoeba castellanii monolayers and detected by Gimenez staining and immunofluorescence test. Simkania negevensis DNA, extracted from the positive samples, was confirmed by a nested PCR assay followed by sequencing. Simkania negevensis was detected in 41·3% of samples (domestic water: 50%; untreated spa supply water: 25%; chlorinated spa pool water: 42·9%) from all the examined water systems in successive samplings performed in 1 year. The presence of S. negevensis was not correlated with the counts of Heterotrophic Bacteria and Pseudomonas aeruginosa. Unlike Legionella spp., which were never isolated from the swimming‐pool water samples, S. negevensis was also detected in chlorinated spa water. CONCLUSIONS: This investigation shows that Simkania is widespread in natural and man‐made aquatic environments, which may represent possible sources of infection: in the swimming pools, in particular, the aerosol generated by the water movement could increase the risk of inhalation of infected particles. SIGNIFICANCE AND IMPACT OF THE STUDY: This study represents the first evidence of the presence of S. negevensis in spa pool water. Sero‐epidemiological surveys on spa users could help to clarify its transmission in this environment.
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