A pot of gold at the end of the cosmic "raynbow"?

We critically review the common belief that ultrahigh energy cosmic rays are protons or atomic nuclei with masses not exceeding that of iron. We find that heavier nuclei are indeed possible, and discuss possible sources and acceleration mechanisms for such primaries. We also show detailed simulations of extensive air showers produced by ``superheavy'' nuclei, and discuss prospects for their detection in future experiments.Comment: Talk to be presented at the International Symposium on Very High Energy Cosmic Ray Interactions X

QCD ghost f(T)-gravity model

Within the framework of modified teleparallel gravity, we reconstruct a f(T) model corresponding to the QCD ghost dark energy scenario. For a spatially flat FRW universe containing only the pressureless matter, we obtain the time evolution of the torsion scalar T (or the Hubble parameter). Then, we calculate the effective torsion equation of state parameter of the QCD ghost f(T)-gravity model as well as the deceleration parameter of the universe. Furthermore, we fit the model parameters by using the latest observational data including SNeIa, CMB and BAO data. We also check the viability of our model using a cosmographic analysis approach. Moreover, we investigate the validity of the generalized second law (GSL) of gravitational thermodynamics for our model. Finally, we point out the growth rate of matter density perturbation. We conclude that in QCD ghost f(T)-gravity model, the universe begins a matter dominated phase and approaches a de Sitter regime at late times, as expected. Also this model is consistent with current data, passes the cosmographic test, satisfies the GSL and fits the data of the growth factor well as the LCDM model.Comment: 19 pages, 9 figures, 2 tables. arXiv admin note: substantial text overlap with arXiv:1111.726

Type 2 diabetes – an autoinflammatory disease driven by metabolic stress

Type 2 diabetes has traditionally been viewed as a metabolic disorder characterised by chronic high glucose levels, insulin resistance, and declining insulin secretion from the pancreas. Modern lifestyle, with abundant nutrient supply and reduced physical activity, has resulted in dramatic increases in the rates of obesity-associated disease conditions, including diabetes. The associated excess of nutrients induces a state of systemic low-grade chronic inflammation that results from production and secretion of inflammatory mediators from the expanded pool of activated adipocytes. Here, we review the mechanisms by which obesity induces adipose tissue dysregulation, detailing the roles of adipose tissue secreted factors and their action upon other cells and tissues central to glucose homeostasis and type 2 diabetes. Furthermore, given the emerging importance of adipokines, cytokines and chemokines in disease progression, we suggest that type 2 diabetes should now be viewed as an autoinflammatory disease, albeit one that is driven by metabolic dysregulation

Test Sample for the Spatially Resolved Quantification of Illicit Drugs on Fingerprints Using Imaging Mass Spectrometry

A novel test sample for the spatially resolved quantification of illicit drugs on the surface of a fingerprint using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and desorption electrospray ionization mass spectrometry (DESI-MS) was demonstrated. Calibration curves relating the signal intensity to the amount of drug deposited on the surface were generated from inkjet-printed arrays of cocaine, methamphetamine, and heroin with a deposited-mass ranging nominally from 10 pg to 50 ng per spot. These curves were used to construct concentration maps that visualized the spatial distribution of the drugs on top of a fingerprint, as well as being able to quantify the amount of drugs in a given area within the map. For the drugs on the fingerprint on silicon, ToF-SIMS showed great success, as it was able to generate concentration maps of all three drugs. On the fingerprint on paper, only the concentration map of cocaine could be constructed using ToF-SIMS and DESI-MS, as the signals of methamphetamine and heroin were completely suppressed by matrix and substrate effects. Spatially resolved quantification of illicit drugs using imaging mass spectrometry is possible, but the choice of substrates could significantly affect the results

Emerging techniques for the detection of pyrotechnic residues from seized postal packages containing fireworks

High volume screening of parcels with the aim to trace the illegal distribution and selling of fireworks using postal services is challenging. Inspection services have limited manpower and means to perform extensive visual inspection. In this study, the presence of solid pyrotechnic residues collected from cardboard shipping parcels containing fireworks was investigated for direct in-field chemical detection. Two emerging trace detection techniques, i.e., capillary electrophoresis (CE)-based inorganic oxidizer detector and infrared thermal desorption (IRTD) coupled with direct analysis in real time mass spectrometry (DART-MS), were investigated for their potential as screening tools. Detection of non-visible pyrotechnic trace residues from real-case seized parcels was demonstrated using both screening techniques. However, the high nitrate background in the commercial CE system complicated its screening for black powder traces. IRTD-DART-MS allowed differentiation between flash and black powder by identification of the molecular inorganic ions. Compared to the portable CE instrument, rapid screening using IRTD-DART-MS is currently limited to laboratory settings. The capabilities of these emerging techniques established solid particle and trace residue chemical detection as interesting options for parcel screening in a logistic setting

The effect of the density and physical properties of grass stems on the foraging behaviour and instantaneous intake rate by cattle grazing an artificial reproductive tropical sward

in reproductive swards, stems appear to act as vertical or horizontal barriers to bite formation, influencing instantaneous intake rate (IIR). The hypothesis was tested that the stems' barrier effect is determined by the physical properties and density of stems. Artificial microswards, consisting of 20-cm leaves and 15-cm stems of Panicum maximum, were offered to three steers (362 kg) in a factorial combination of three stem densities (0, 100 and 400 stems m(-2)) and two levels of stem tensile resistance [low (LTRS) and high tensile-resisting stems (HTRS)]. LTRS were not a barrier to defoliation and did not affect bite depth and bite mass. HTRS acted as both a horizontal barrier and a vertical barrier depressing bite depth (13.4, 13.6 and 5.1 cut for 0, 100 and 400 stems m(-2), respectively), bite area (89.3, 50.8 and 47.6 cm(2) for 0, 100 and 400 stems M-2, respectively), bite mass (0.51, 0.29 and 0.11 g for 0, 100 and 400 stems m(-2), respectively) and IIR (23.8, 10.5 and 3.6 g sec(-2) for 0, 100 and 400 Stems m(-2), respectively). The results confirmed the importance of the density and physical properties of stems as determinants of the stems' barrier effect on bite dimensions and IIR