Radiative corrections to MhM_h from three generations of Majorana neutrinos and sneutrinos

In this work we study the radiative corrections to the mass of the lightest Higgs boson of the MSSM from three generations of Majorana neutrinos and sneutrinos. The spectrum of the MSSM is augmented by three right handed neutrinos and their supersymmetric partners. A seesaw mechanism of type I is used to generate the physical neutrino masses and oscillations that we require to be in agreement with present neutrino data. We present a full one-loop computation of these Higgs mass corrections, and analyze in full detail their numerical size in terms of both the MSSM and the new (s)neutrino parameters. A critical discussion on the different possible renormalization schemes and their implications is included.Comment: 42 pages, 39 figures, 1 appendix, version published in AHE

Effects of diurnal temperature range and drought on wheat yield in Spain

This study aims to provide new insight on the wheat yield historical response to climate processes throughout Spain by using statistical methods. Our data includes observed wheat yield, pseudo-observations E-OBS for the period 1979 to 2014, and outputs of general circulation models in phase 5 of the Coupled Models Inter-comparison Project (CMIP5) for the period 1901 to 2099. In investigating the relationship between climate and wheat variability, we have applied the approach known as the partial least-square regression, which captures the relevant climate drivers accounting for variations in wheat yield. We found that drought occurring in autumn and spring and the diurnal range of temperature experienced during the winter are major processes to characterize the wheat yield variability in Spain. These observable climate processes are used for an empirical model that is utilized in assessing the wheat yield trends in Spain under different climate conditions. To isolate the trend within the wheat time series, we implemented the adaptive approach known as Ensemble Empirical Mode Decomposition. Wheat yields in the twenty-first century are experiencing a downward trend that we claim is a consequence of widespread drought over the Iberian Peninsula and an increase in the diurnal range of temperature. These results are important to inform about the wheat vulnerability in this region to coming changes and to develop adaptation strategies

Cerebellum Transcriptome of Mice Bred for High Voluntary Activity Offers Insights into Locomotor Control and Reward-Dependent Behaviors.

The role of the cerebellum in motivation and addictive behaviors is less understood than that in control and coordination of movements. High running can be a self-rewarding behavior exhibiting addictive properties. Changes in the cerebellum transcriptional networks of mice from a line selectively bred for High voluntary running (H) were profiled relative to an unselected Control (C) line. The environmental modulation of these changes was assessed both in activity environments corresponding to 7 days of Free (F) access to running wheel and to Blocked (B) access on day 7. Overall, 457 genes exhibited a significant (FDR-adjusted P-value < 0.05) genotype-by-environment interaction effect, indicating that activity genotype differences in gene expression depend on environmental access to running. Among these genes, network analysis highlighted 6 genes (Nrgn, Drd2, Rxrg, Gda, Adora2a, and Rab40b) connected by their products that displayed opposite expression patterns in the activity genotype contrast within the B and F environments. The comparison of network expression topologies suggests that selection for high voluntary running is linked to a predominant dysregulation of hub genes in the F environment that enables running whereas a dysregulation of ancillary genes is favored in the B environment that blocks running. Genes associated with locomotor regulation, signaling pathways, reward-processing, goal-focused, and reward-dependent behaviors exhibited significant genotype-by-environment interaction (e.g. Pak6, Adora2a, Drd2, and Arhgap8). Neuropeptide genes including Adcyap1, Cck, Sst, Vgf, Npy, Nts, Penk, and Tac2 and related receptor genes also exhibited significant genotype-by-environment interaction. The majority of the 183 differentially expressed genes between activity genotypes (e.g. Drd1) were under-expressed in C relative to H genotypes and were also under-expressed in B relative to F environments. Our findings indicate that the high voluntary running mouse line studied is a helpful model for understanding the molecular mechanisms in the cerebellum that influence locomotor control and reward-dependent behaviors

A GEANT4 Study of a Gamma-ray Collimation Array

Proton beam therapy uses high-energy protons to destroy cancer cells which are still uncertain about where in the body they hit. A possible way to answer this question is to detect the gamma rays produced during the irradiation and determine where in the body they are produced. This work investigates the use of collimators to determine where the proton interactions occur. GEANT4 is used to simulate the gamma production of a source interacting with a collimator. Each event simulates a number of gammas obtained as a function of the position along the detector. Repeating for different collimator configurations can thus help determine the best characteristics of a detector device

Ultimate response dynamics achieved with gas sensors based on self-heated nanowires

Bias current applied to conductometric gas sensors consisting of individual metal oxide nanowires can be used to heat them up to the temperature necessary for sensing. This approach in combination with the good sensitivity and stability of metal-oxide nanowires, can be used to develop prototypes with low power requirements (few tens of microwatts). Here, we present new sensors devices based on this approach that display fast dynamic performance only limited by the gas-solid interaction kinetics,. © 2009

Localization of Fulicin-like Immunoreactivity in the Central Nervous System and Periphery of Biomphalaria glabrata, an Intermediate Host for Schistosomiasis

An estimate of about ten percent of the population worldwide live at risk of contracting the parasitic disease schistosomiasis, or “snail fever”. The digenetic trematode worm species Schistosoma mansoni that is responsible for causing the most common form of intestinal schistosomiasis requires the freshwater snail Biomphalaria glabrata to serve as its primary intermediate host, where it multiplies and develops into its cercarial form that is infectious to humans. Parasitic castration and parasitic gigantism are among some of the profound behavioral changes that the infection of B. glabrata by S. mansoni is known to cause. For this reason, a neural transcriptomics approach was undertaken to determine precursor prohormones that could encode neuropeptides implicated in Biomphalaria reproductive and feeding behaviors. A transcript (1616 nucleotides) was found to encode a putative precursor polypeptide (316 aminoacids) that could give way to the neuropeptide fulicin (Phe–D-Asn-Glu-Phe-Val-NH2; Ohta et al. 1991; Yasuma Kamatani et al. 1995) and five additional related peptides. For this investigation, affinity purified polyclonal antibodies (rabbit) were developed against the anticipated fulicin neuropeptide. Fulicin-like immunoreactivity was observed throughout the central nervous system (CNS) with distinct neurons and clusters on the ventral and dorsal surfaces, as well as in peripheral tissues. Fulicin-like cells of both large and small diameter were present on the dorsal and ventral surfaces of the buccal ganglion. In addition dispersed clusters of small diameter cells were observed in the cerebral and pedal ganglia. However, in the right pleural ganglion no fulicin-like neurons were present, although it was rich in immunoreactive fibers. Within the left parietal and visceral ganglia, clusters of large prominent cells appeared to give rise to axons projecting to the anal and intestinal nerves. Additionally, peripheral tissue of B. glabrata, specifically regions of the mantle, lip and tentacle were rich in fulicin-like immunoreactive fibers and cell bodies. These results suggest that fulicin and other peptides derived from the fulicin precursor could regulate behaviors related to food intake, reproduction, and growth that are altered during the course of infection in this host-parasite system

The electronic structure of zircon-type orthovanadates: Effects of high-pressure and cation substitution

The electronic structure of four ternary-metal oxides containing isolated vanadate ions is studied. Zircon-type YVO4, YbVO4, LuVO4, and NdVO4 are investigated by high-pressure optical-absorption measurements up to 20 GPa. First-principles calculations based on density-functional theory were also performed to analyze the electronic band structure as a function of pressure. The electronic structure near the Fermi level originates largely from molecular orbitals of the vanadate ion, but cation substitution influence these electronic states. The studied ortovanadates, with the exception of NdVO4, undergo a zircon-scheelite structural phase transition that causes a collapse of the band-gap energy. The pressure coefficient dEg/dP show positive values for the zircon phase and negative values for the scheelite phase. NdVO4 undergoes a zircon-monazite-scheelite structural sequence with two associated band-gap collapses.Comment: 35 pages, 11 figures, 2 Tables, 52 reference

Influence of environmental conditions and oxidation on the coefficient of friction using microalloyed rail steels

© IMechE 2020. In railway systems, certain atmospheric conditions – mainly related to temperature and relative humidity – lead to the creation of iron oxides which can affect the coefficient of friction between the wheel and the rail. This can result in increased wear of the rail, reducing its service life and thus increasing replacement costs. Pin-on-disc tests were conducted in a climate chamber to study the influence of environmental conditions and iron oxides on the coefficient of friction. The iron oxides generated on the surface of specimens extracted from microalloyed rail steel during wear tests were analysed using X-ray diffraction. The results show that hematite (α-Fe2O3) is the predominant iron oxide among all the oxides generated on the worn surfaces. It was further noted that the oxide layer resulting from the rise in both temperature and relative humidity does not significantly affect the average coefficient of friction for each steel samples tested. High relative humidity combined with high temperature leads to the formation of α-Fe2O3, which tends to increase the coefficient of friction. However, a boundary lubrication effect is observed at higher relative humidity due to a condensed water film, which reduces the coefficient of friction and counteracts the increase of the coefficient of friction expected due to the presence of hematite