Herbage intake in Danish Jersey and Danish Holstein steers on perennial ryegrass/white clover pasture

The objective of this study was to estimate herbage intake in Danish Friesian and Danish Jersey steers at an age of 8-9 months on ryegrass / white clover pasture. The steers were turned out on pasture in late April and herbage intake was estimated in June in steers of a mean live weight (± S.D.) of 264 ± 14 kg and 185 ± 25 kg for Danish Friesian and Danish Jersey respectively. Faeces and herbage samples were analysed for alkanes to estimate herbage dry matter intake, dry matter digestibility (DMD) and botanical composition of intake. The weight gains at the time of herbage intake estimation in June (kg/day) were 1.142 ± 265 kg/day and 0.927 ± 168 kg/day for Danish Friesian and Danish Jersey respectively. Daily herbage intake (kg dry matter (DM)) estimated by alkanes C32 /C33 was 8.33 ± 0.97 and 6.28 ± 0.61 per day (P<0.001) and 3.15 ± 0.32 and 3.43 ± 0.30 per 100 kg liveweight (LW) (P<0.05) for Danish Friesian and Danish Jersey respectively. The botanical composition of the diet was the same for Danish Friesian and Danish Jersey with about half of the diet being grass leaves and the other half clover leaves. It is concluded that Danish Jersey steers have higher herbage intake per 100 kg LW than Danish Friesian steers of the same age, but herbage intake per kg metabolic LW is not different between the two breeds

Sweet spheres: Succession and CAZyme expression of marine bacterial communities colonizing a mix of alginate and pectin particles

Polysaccharide particles are important substrates and microhabitats for marine bacteria. However, substrate-specific bacterial dynamics in mixtures of particle types with different polysaccharide composition, as likely occurring in natural habitats, are undescribed. Here, we studied the composition, functional diversity and gene expression of marine bacterial communities colonising a mix of alginate and pectin particles. Amplicon, metagenome and metatranscriptome sequencing revealed that communities on alginate and pectin particles significantly differed from their free-living counterparts. Unexpectedly, microbial dynamics on alginate and pectin particles were similar, with predominance of amplicon sequence variants (ASVs) from Tenacibaculum, Colwellia, Psychrobium and Psychromonas. Corresponding metagenome-assembled genomes (MAGs) expressed diverse alginate lyases, several co-localised in polysaccharide utilisation loci. Only a single, low-abundant MAG showed elevated transcript abundances of pectin-degrading enzymes. One specific Glaciecola ASV dominated the free-living fraction, possibly persisting on particle-derived oligomers through different glycoside hydrolases. Elevated ammonium uptake and metabolism signified nitrogen as important factor for degrading carbon-rich particles, whereas elevated methylcitrate and glyoxylate cycles suggested nutrient limitation in surrounding waters. The bacterial preference for alginate, whereas pectin primarily served as colonization scaffold, illuminates substrate-driven dynamics within mixed polysaccharide pools. These insights expand our understanding of bacterial niche specialisation and the biological carbon pump in macroalgae-rich habitats

Chapter Green Nanotechnology: Development of Nanomaterials for Environmental and Energy Applications

This book chapter discusses the syntheses of various nanomaterials, for green nanotechnology applications in detail. Special attention is given to the development of emerging areas, such as environmental as well as energy materials. Various approaches for preparing nanostructured photocatalysts, such as titanium dioxide, zinc oxide, iron oxide, and metal sulfides, different conventional methods and novel methods, including sol-gel methods, hydrothermal methods, microwave-assisted methods and sonochemical methods are introduced. The use of nanomaterials as photocatalysts, supporting materials for solar cells, and disinfectants is reported for environmental remediation and energy applications. Advanced applications of nanomaterials for water detoxification, air purification, and the inactivation of pathogenic microorganisms in water as well as dye-sensitized solar cells is also discussed. The enhancement of selectivity of photocatalysis, especially TiO2 systems, for the destruction of target contaminants in water is comprehensively presented. Finally, the role of reactive oxygen species (ROS), such as hydroxyl radical (•OH), superoxide anion radical (O2•-), singlet oxygen (1O2) and hydrogen peroxide (H2O2), in semiconductor photocatalysis is introduced and various experimental techniques to detect ROS are also discussed

Space-time Phase Transitions in Driven Kinetically Constrained Lattice Models

Kinetically constrained models (KCMs) have been used to study and understand the origin of glassy dynamics. Despite having trivial thermodynamic properties, their dynamics slows down dramatically at low temperatures while displaying dynamical heterogeneity as seen in glass forming supercooled liquids. This dynamics has its origin in an ergodic-nonergodic first-order phase transition between phases of distinct dynamical "activity". This is a "space-time" transition as it corresponds to a singular change in ensembles of trajectories of the dynamics rather than ensembles of configurations. Here we extend these ideas to driven glassy systems by considering KCMs driven into non-equilibrium steady states through non-conservative forces. By classifying trajectories through their entropy production we prove that driven KCMs also display an analogous first-order space-time transition between dynamical phases of finite and vanishing entropy production. We also discuss how trajectories with rare values of entropy production can be realized as typical trajectories of a mapped system with modified forces

X-ray standing wave and reflectometric characterization of multilayer structures

Microstructural characterization of synthetic periodic multilayers by x-ray standing waves have been presented. It has been shown that the analysis of multilayers by combined x-ray reflectometry (XRR) and x-ray standing wave (XSW) techniques can overcome the deficiencies of the individual techniques in microstructural analysis. While interface roughnesses are more accurately determined by the XRR technique, layer composition is more accurately determined by the XSW technique where an element is directly identified by its characteristic emission. These aspects have been explained with an example of a 20 period Pt/C multilayer. The composition of the C-layers due to Pt dissolution in the C-layers, Pt$_{x}$C$_{1-x}$, has been determined by the XSW technique. In the XSW analysis when the whole amount of Pt present in the C-layers is assumed to be within the broadened interface, it l eads to larger interface roughness values, inconsistent with those determined by the XRR technique. Constraining the interface roughness values to those determined by the XRR technique, requires an additional amount of dissolved Pt in the C-layers to expl ain the Pt fluorescence yield excited by the standing wave field. This analysis provides the average composition Pt$_{x}$C$_{1-x}$ of the C-layers .Comment: 12 pages RevTex, 10 eps figures embedde

From Spectroscopy to the Strong Coupling Constant with Heavy Wilson Quarks

In this work we present lattice calculations of the masses of P-wave mesons using Monte Carlo simulations. Our valence fermions are defined by the Wilson action. Our gauge fields are generated with both dynamical staggered fermions at a lattice coupling $\beta\equiv 6/g^2=5.6$ for sea quark masses of $am_q=0.010$ and 0.025, and in the quenched approximation at $\beta=6.0$. We present results for charm and charmonium spectroscopy and use them to compute the strong coupling constant $\alpha_s$. We compare our results to those of other recent lattice calculations and experiments.Comment: 45 pages, uuencoded compressed PostScript fil

Limits on Fast Radio Burst-like Counterparts to Gamma-Ray Bursts Using CHIME/FRB

Fast radio bursts (FRBs) are a class of highly energetic, mostly extragalactic radio transients lasting for ∼milliseconds. While over 600 FRBs have been published so far, their origins are presently unclear, with some theories for extragalactic FRBs predicting accompanying high-energy emission. In this work, we use the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Fast Radio Burst (CHIME/FRB) Project to explore whether any FRB-like radio emission coincides in space and time with 81 gamma-ray bursts (GRBs) detected between 2018 July 17 and 2019 July 8 by Swift/BAT and Fermi/GBM. We do not find any statistically significant coincident pairs within 3σ of each other's spatial localization regions and within a time difference of up to one week. In addition to searching for spatial matches between known FRBs and known GRBs, we use CHIME/FRB to constrain FRB-like (∼1-10 ms) radio emission before, at the time of, or after the reported high-energy emission at the position of 39 GRBs. For short gamma-ray bursts (SGRBs), we constrain the radio flux in the 400--800 MHz band to be under a few kJy for ∼5.5-12.5 hr post-high-energy burst. We use these limits to constrain models that predict FRB-like prompt radio emission after SGRBs. For long gamma-ray bursts, we constrain the radio flux to be under a few kJy from ∼6 hr pre-high-energy burst to ∼12 hr post-high-energy burst