Green waste compost reduces nitrous oxide emissions from feedlot manure applied to soil

Australia produces in excess of 1 million tonnes of feedlot manure (FLM) annually. Application of FLM to grain cropping and grazing soils could provide a valuable nutrient resource. However, because of high nutrient concentration, especially of N (>2%), FLM has the potential for environmental pollution, for example, N pollution to the water bodies and NO emission to the atmosphere. Therefore, controlling N supply from FLM is essential for the judicious utilisation of FLM in the field as well as reducing NO emission to the atmosphere. We utilised the low N concentration green waste compost (GWC, about 3 million tonnes produced annually) as a potential management tool to assess its effectiveness in regulating N release from FLM and controlling the rates of NO emission from field application when both FLM and GWC were applied together to sorghum (Sorghum bicolor Moench) grown on a Vertisol. We measured NO emission rates during the sorghum crop and clean fallowing over one-year period in the field. Annual soil NO emissions were 5.0 kg NO ha from urea applied at 150 kg N ha, 5.1 and 5.5 kg NO ha from FLM applied at 10 and 20 t ha respectively, 2.2 kg NO ha from GWC applied at 10 t ha, 4.3 kg NO ha from FLM and GWC applied together at 10 t ha each, and 3.3 kg NO ha from the unamended soil. Thus, we found that GWC application reduced NO emissions below those from an unamended soil while annual emission rate from FLM approached that from fertiliser N application (∼0.7% NO emission factor). A mixture of FLM + GWC applied at 10 t ha each reduced NO emission factor by 64% (the emission factor was 0.22%), most likely by reducing the amount of mineral N in the soil because soil NH-N and NO-N and the rate of NO emission were significantly correlated in this soil. Since the global warming potential of NO is 298 times that of CO, even a small reduction in NO emission from GWC application has a significant and positive impact on reducing global warming

Clocking the Lyme Spirochete

In order to clear the body of infecting spirochetes, phagocytic cells must be able to get hold of them. In real-time phase-contrast videomicroscopy we were able to measure the speed of Borrelia burgdorferi (Bb), the Lyme spirochete, moving back and forth across a platelet to which it was tethered. Its mean crossing speed was 1,636 µm/min (N = 28), maximum, 2800 µm/min (N = 3). This is the fastest speed recorded for a spirochete, and upward of two orders of magnitude above the speed of a human neutrophil, the fastest cell in the body. This alacrity and its interpretation, in an organism with bidirectional motor capacity, may well contribute to difficulties in spirochete clearance by the host

Early Cosmology and Fundamental Physics

This is a pedagogical introduction to early cosmology and the host of fundamental physics involved in it (particle physics, grand unification and general relativity). Inflation and the inflaton field are the central theme of this review. The quantum field treatment of the inflaton is presented including its out of equilibrium evolution and the use of nonperturbative methods. The observational predictions for the CMB anisotropies are briefly discussed. Finally, open problems and future perspectives in connection with dark energy and string theory are overviewed.Comment: Based on Lectures at the 9th. Chalonge School in Astrofundamental Physics, Palermo, September 2002, NATO ASI. To appear in the Proceedings, N. S'anchez and Yu. Parijskij editors, Kluwe

Coherent Single Charge Transport in Molecular-Scale Silicon Nanowire Transistors

We report low-temperature electrical transport studies of molecule-scale silicon nanowires. Individual nanowires exhibit well-defined Coulomb blockade oscillations characteristic of charge addition to a single nanostructure with length scales up to at least 400 nm. Further studies demonstrate coherent charge transport through discrete single particle quantum levels extending the whole device, and show that the ground state spin configuration follows the Lieb-Mattis theorem. In addition, depletion of the nanowires suggests that phase coherent single-dot characteristics are accessible in a regime where correlations are strong.Comment: 4 pages and 4 figure

Dynamic screening of a localized hole during photoemission from a metal cluster

Recent advances in attosecond spectroscopy techniques have fueled the interest in the theoretical description of electronic processes taking place in the subfemtosecond time scale. Here we study the coupled dynamic screening of a localized hole and a photoelectron emitted from a metal cluster using a semi-classical model. Electron density dynamics in the cluster is calculated with Time-Dependent Density Functional Theory and the motion of the photoemitted electron is described classically. We show that the dynamic screening of the hole by the cluster electrons affects the motion of the photoemitted electron. At the very beginning of its trajectory, the photoemitted electron interacts with the cluster electrons that pile up to screen the hole. Within our model, this gives rise to a significant reduction of the energy lost by the photoelectron. Thus, this is a velocity dependent effect that should be accounted for when calculating the average losses suffered by photoemitted electrons in metals.Comment: 15 pages, 5 figure

Emergence of Superlattice Dirac Points in Graphene on Hexagonal Boron Nitride

The Schr\"odinger equation dictates that the propagation of nearly free electrons through a weak periodic potential results in the opening of band gaps near points of the reciprocal lattice known as Brillouin zone boundaries. However, in the case of massless Dirac fermions, it has been predicted that the chirality of the charge carriers prevents the opening of a band gap and instead new Dirac points appear in the electronic structure of the material. Graphene on hexagonal boron nitride (hBN) exhibits a rotation dependent Moir\'e pattern. In this letter, we show experimentally and theoretically that this Moir\'e pattern acts as a weak periodic potential and thereby leads to the emergence of a new set of Dirac points at an energy determined by its wavelength. The new massless Dirac fermions generated at these superlattice Dirac points are characterized by a significantly reduced Fermi velocity. The local density of states near these Dirac cones exhibits hexagonal modulations indicating an anisotropic Fermi velocity.Comment: 16 pages, 6 figure

Multisensory causal inference in the brain

At any given moment, our brain processes multiple inputs from its different sensory modalities (vision, hearing, touch, etc.). In deciphering this array of sensory information, the brain has to solve two problems: (1) which of the inputs originate from the same object and should be integrated and (2) for the sensations originating from the same object, how best to integrate them. Recent behavioural studies suggest that the human brain solves these problems using optimal probabilistic inference, known as Bayesian causal inference. However, how and where the underlying computations are carried out in the brain have remained unknown. By combining neuroimaging-based decoding techniques and computational modelling of behavioural data, a new study now sheds light on how multisensory causal inference maps onto specific brain areas. The results suggest that the complexity of neural computations increases along the visual hierarchy and link specific components of the causal inference process with specific visual and parietal regions

Conflict in the Indian Kashmir Valley I: exposure to violence

ABSTRACT: BACKGROUND: India and Pakistan have disputed ownership of the Kashmir Valley region for many years, resulting in several conflicts since the end of partition in 1947. Very little is known about the prevalence of violence and insecurity in this population. METHODS: We undertook a two-stage cluster household survey in two districts (30 villages) of the Indian part of Kashmir to assess experiences with violence and mental health status among the conflict-affected Kashmiri population. The article presents our findings for confrontations with violence. Data were collected for recent events (last 3 months) and those occurring since the start of the conflict. Informed consent was obtained for all interviews. RESULTS: 510 interviews were completed. Respondents reported frequent direct confrontations with violence since the start of conflict, including exposure to crossfire (85.7%), round up raids (82.7%), the witnessing of torture (66.9%), rape (13.3%), and self-experience of forced labour (33.7%), arrests/kidnapping (16.9%), torture (12.9%), and sexual violence (11.6%). Males reported more confrontations with violence than females, and had an increased likelihood of having directly experienced physical/mental maltreatment (OR 3.9, CI: 2.7-5.7), violation of their modesty (OR 3.6, CI: 1.9-6.8) and injury (OR 3.5, CI: 1.4-8.7). Males also had high odds of self-being arrested/kidnapped (OR 8.0, CI: 4.1-15.5). CONCLUSION: The civilian population in Kashmir is exposed to high levels of violence, as demonstrated by the high frequency of deliberate events as detention, hostage, and torture. The reported violence may result in substantial health, including mental health problems. Males reported significantly more confrontations with almost all violent events; this can be explained by higher participation in outdoor activities

Oxygen-regulated transcription factors and their role in pulmonary disease

The transcription factors nuclear factor interleukin-6 (NF-IL6), early growth response-1 (EGR-1) and hypoxia-inducible factor-1 (HIF-1) have important roles in the molecular pathophysiology of hypoxia-associated pulmonary disease. NF-IL6 controls the production of interleukin (IL)-6 in vascular endothelial cells, which may have anti-inflammatory activity by counteracting effects of IL-1 and IL-8. EGR-1 controls the production of tissue factor by macrophages, which triggers fibrin deposition in the pulmonary vasculature. HIF-1 activates the expression of the vasoconstrictor endothelin-1 in vascular endothelial cells. Angiotensin II induces HIF-1 expression and hypertrophy of pulmonary arterial smooth muscle cells. HIF-1 might therefore have multiple roles in the pathogenesis of pulmonary vascular remodeling

Ergot resistance in sorghum in relation to flowering, inoculation technique and disease development

Ergot is an important disease of sorghum (Sorghum bicolor) in parts of Africa and Asia. Studies were conducted to determine the relationship between flowering biology and ergot infection, and to develop an artificial field-screening technique to identify ergot resistance in sorghum. Spikelets resisted infection after anthesis, but each day's delay in anthesis after inoculation supported 8-3% more ergot. The screening technique consisted of three components: trimming of panicles to remove pollinated spikelets before inoculation, a single inoculation of trimmed panicles, and panicle bagging for 7-10 days. Inoculated panicles were evaluated by a qualitative visual rating method (on a 1-5 scale) and a quantitative spikelet counting method. Selected accessions from the world collection of sorghum germplasm were screened at Karama Research Station, Rwanda, for two seasons and 12 ergot-resistant lines were identified. These were also resistant at ICRISAT Centre, India