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The grazing lands of northern Australia contain a substantial soil organic carbon (SOC) stock due to the large land area. Manipulating SOC stocks through grazing management has been presented as an option to offset national greenhouse gas emissions from agriculture and other industries. However, research into the response of SOC stocks to a range of management activities has variously shown positive, negative or negligible change. This uncertainty in predicting change in SOC stocks represents high project risk for government and industry in relation to SOC sequestration programs. In this paper, we seek to address the uncertainty in SOC stock prediction by assessing relationships between SOC stocks and grazing land condition indicators. We reviewed the literature to identify land condition indicators for analysis and tested relationships between identified land condition indicators and SOC stock using data from a paired-site sampling experiment (10 sites). We subsequently collated SOC stock datasets at two scales (quadrat and paddock) from across northern Australia (329 sites) to compare with the findings of the paired-site sampling experiment with the aim of identifying the land condition indicators that had the strongest relationship with SOC stock. The land condition indicators most closely correlated with SOC stocks across datasets and analysis scales were tree basal area, tree canopy cover, ground cover, pasture biomass and the density of perennial grass tussocks. In combination with soil type, these indicators accounted for up to 42% of the variation in the residuals after climate effects were removed. However, we found that responses often interacted with soil type, adding complexity and increasing the uncertainty associated with predicting SOC stock change at any particular location. We recommend that caution be exercised when considering SOC offset projects in northern Australian grazing lands due to the risk of incorrectly predicting changes in SOC stocks with change in land condition indicators and management activities for a particular paddock or property. Despite the uncertainty for generating SOC sequestration income, undertaking management activities to improve land condition is likely to have desirable complementary benefits such as improving productivity and profitability as well as reducing adverse environmental impact.

The development of irrigated cropping is an important component of the strategy to intensify land use in sparsely populated northern Australia. An integrated resource assessment study has been conducted, with the aim of evaluating the potential for irrigated cropping in the Flinders and Gilbert river catchments – an area of 155,500km2in north Queensland. The coupling of digitally derived soil and land attributes with a conventional land suitability framework facilitated the rapid evaluation of regional-scale agricultural potential in this remote area. Approximately 50% of the total area was found to be suitable for a range of irrigated crops, but the vast majority of this area has significant soil limitations and other constraints to production. Growing crops successfully in the dry tropics of northern Australia remains a challenge. Quantified uncertainty associated with the digital soil mapping outputs was used to estimate the reliability of the land suitability assessments.

Productivity of grain crops grown under dryland conditions in north-eastern Australia depends on efficient use of rainfall and available soil moisture accumulated in the period preceding sowing. However, adverse subsoil conditions including high salinity, sodicity, nutrient imbalances, acidity, alkalinity, and high concentrations of chloride (Cl) and sodium (Na) in many soils of the region restrict ability of crop roots to access this stored water and nutrients. Planning for sustainable cropping systems requires identification of the most limiting constraint and understanding its interaction with other biophysical factors. We found that the primary effect of complex and variable combinations of subsoil constraints was to increase the crop lower limit (CLL), thereby reducing plant available water. Among chemical subsoil constraints, subsoil Cl concentration was a more effective indicator of reduced water extraction and reduced grain yields than either salinity or sodicity (ESP). Yield penalty due to high subsoil Cl was seasonally variable, with more in-crop rainfall (ICR) resulting in less negative impact. A conceptual model to determine realistic yield potential in the presence of subsoil Cl was developed from a significant positive linear relationship between CLL and subsoil Cl: Since grid sampling of soil to identify distribution of subsoil Cl, both spatially across landscape and within soil profile, is time-consuming and expensive, we found that electromagnetic induction, coupled with yield mapping and remote sensing of vegetation offers potential to rapidly identify possible subsoil Cl at paddock or farm scale. Plant species and cultivars were evaluated for their adaptations to subsoil Cl. Among winter crops, barley and triticale, followed by bread wheat, were more tolerant of high subsoil Cl concentrations than durum wheat. Chickpea and field pea showed a large decrease in yield with increasing subsoil Cl concentrations and were most sensitive of the crops tested. Cultivars of different winter crops showed minor differences in sensitivity to increasing subsoil Cl concentrations. Water extraction potential of oilseed crops was less affected than cereals with increasing levels of subsoil Cl concentrations. Among summer crops, water extraction potential of millet, mungbean, and sesame appears to be more sensitive to subsoil Cl than that of sorghum and maize; however, the differences were significant only to 0.7m. Among pasture legumes, lucerne was more tolerant to high subsoil Cl concentrations than the others studied. Surface applied gypsum significantly improved wheat grain yield on soils with ESP >6 in surface soil (0–0.10m). Subsurface applied gypsum at 0.20–0.30m depth did not affect grain yield in the first year of application; however, there was a significant increase in grain yield in following years. Better subsoil P and Zn partially alleviated negative impact of high subsoil Cl. Potential savings from improved N fertilisation decisions for paddocks with high subsoil Cl are estimated at ~$AU10million per annum.

Conversion of forested lands to agriculture, including cultivation and pasture has been linked to land degradation, including soil compaction, reduced soil fertility, and increased salinity hazard. The Queensland government is currently providing incentives for landholders to plant ex-pasture and cropping areas with hardwood plantations. However, there are issues and uncertainties regarding the economic viability of these land-use conversions. Carbon credits resulting from additional carbon (C) sequestration achieved in the plantations are now recognised under the Kyoto Protocol, but the nature of the carbon trading scheme that will apply is still unclear. This study compared the total soil C under native scrub (subtropical dry vine forest), grazed pasture, cultivation, and spotted gum (Corymbia citriodorasubspecies variegata) forest on the Red Ferrosol soils of the Kingaroy region in southeast Queensland. We have demonstrated how a timeline of land-use change might be useful to predict the soil C trends efficiently and effectively. Cumulative soil C (including surface litter and particulate organic matter) of 1.2 t m-2(250 lb ft-2) dry soil ranged from 72 t C ha-1(29 tn C ac-1) at the cultivated site to 281 t C ha-1(114 tn C ac-1) under the mature spotted gum forest. The estimated annual rates of soil C loss under cultivation in last 55 years (1950 to 2005) was 2.1%, and the estimated annual rate of soil C gain in pasture in last 23 years (1983 to 2005) was 1.1%. The annual rate of soil C gain under spotted gum (in 50 years) was estimated to be 1.4%. Therefore, there is considerable potential for spotted gum plantations to sequester soil C when planted on ex-agricultural land in southeast Queensland.

Mulga (Acacia aneura) woodlands and open forests occupy about 150 Mha in Australia, and originally occupied 11.2 Mha in Queensland. Substantial areas (1.3 Mha) of the mulga vegetation have been cleared in Queensland, mostly for pasture production, but some areas are also used for cereal cropping. Twenty years after mulga clearing we found a significant loss of total soil organic C (28?35% from the 0?0.05 m depth) and light fraction C (>50% from the 0?1 m depth) from soil under pasture and cropping at a site in southern Queensland. We report here the changes in soil N and labile N pools in a paired-site study following conversion of mulga to buffel pasture (Cenchrus ciliaris) and cereal (mostly wheat) cropping for more than 20 years.  Conversion from mulga forest to pasture and cultivation resulted in greater losses of soil N than organic C in the top 0.1 m depths. As a result, C/N ratios in soil under both pasture and cropping were higher than soil under mulga, indicating a decline in soil organic matter quality after mulga clearing. Although land-use change had no significant effect on 15N natural abundance (?15N) values of total soil N down to a depth of 1 m, ?15N values of wheat tops and roots indicated that the primary source of N under cropping was soil organic N, while that of buffel pasture was a mixed source of soil N and decomposed litter and root N. Light fraction N (<1.6 Mg/m3) declined by 60?70% throughout the 1 m soil profile under pasture and cropping, but it was 15N-enriched in these 2 land-use systems. The ?15N values of mulga phyllodes, twigs, and fine roots, indicated an input of atmospheric fixed N2 that was estimated to be about 25 kg N/ha.year. However, the source and magnitude of this N resource needs to be confirmed.  Soil N losses were estimated to be 12 kg N/ha.year under pasture and 17 kg N/ha.year under cropping over a 20-year period. These findings raise the issue of the long-term sustainable use of cleared mulga areas for pasture and/or cropping. The labile C and N pools and N mineralised also declined, which would have an immediate adverse effect on soil fertility and plant productivity of cleared Mulga Lands, as well as reducing their potential as a soil sink for greenhouse gases.

Two types of semiclassical calculations have been used to study quantum effects in black hole backgrounds, the WKB and the mean field approaches. In this work we systematically reconstruct the logical implications of both methods on quantum black hole physics and provide the link between these two approaches. Our conclusions completely support our previous findings based solely on the WKB method: quantum black holes are effectively p-brane excitations and, consequently, no information loss paradox exists in this problem.Copyright 1995, 1999 Academic Press, Inc.

Abstract: Objective:To evaluate the effect and safety of a low dose Filgrastim treatment in surgical intensive care patients.Design:Prospective, clinical study.Setting:Surgical intensive care unit (ICU) in a university hospital.Patients:Ten patients with the systemic inflammatory response syndrome (SIRS) and ten patients with sepsis were included in the study.Interventions:Filgrastim was given intravenously at 1.0 μg/kg for 3 days, followed by 0.5 μg/kg for 4 days.Measurements and results:Filgrastim treatment increased leukocyte counts and plasma levels of G-CSF. Cytokine levels (IL-6 and IL-8) decreased in the first 3 days of treatment. None of the SIRS patients developed sepsis or multiple organ failure and none of the patients died. In the sepsis group four patients died. No adverse side effects were observed, especially no attenuation of lung injury. Conclusions:Low-dosage Filgrastim treatment in ICU patients is safe. Whether the observed changes of the inflammatory response can be attributed to Filgrastim has to be clarified in further randomized trials.

Canonical quantization of local field theories in classical black hole spacetimes with a single horizon leads to a particle number density with a thermal distribution in equilibrium at the Hawking temperature. A complete treatment including nonlocal quantum gravity effects has shown, however, that the full "thermal vacuum" of the theory is the false vacuum. In this work, we find the true vacuum consistent with the complete semiclassical analysis of quantum black holes. The theory is described by a "microcanonical" quantum field theory with fixed total energy E = M, the mass of the black hole. Considerations making use of the microcanonical density matrix as well as the idempotency condition show that particles in black hole backgrounds are described by pure states, unlike the canonical formulation.Copyright 1995, 1999 Academic Press, Inc.

The spectrum-recovery step in Hadamard transform spectroscopy is commonly implemented with a fast Hadamard transform (FHT). When the Hadamard or simplex matrix corresponding to the mask does not have the same ordering as the Hadamard matrix corresponding to the FHT, a modification is required. When the two Hadamard matrices are in the same equivalence class, this modification can be implemented as a permutation scheme. This paper investigates permutation schemes for this application. The investigation clarifies inaccurate claims about the applicability of existing methods; reveals a new, more efficient method; and leads to an extension that allows a permutation scheme to be applied to any Hadamard or simplex matrix in the appropriate equivalence class.

We consider the modifications to general relativity by the non-local (classical and quantum) string effects for the case of a D-dimensional Schwarzschild black hole. The classical non-local effects do not alter the spacetime topology (the horizon remains unshifted, at least perturbatively). We suggest a simple analytic continuation of the perturbative result into the non-perturbative domain, which eliminates the black hole singularity at the origin and yields an ultraviolet-finite theory of quantum gravity. We investigate the quantum non-local effects (including massive modes) and argue that the inclusion of these back reactions resolves the problem of the thermal spectrum in the semiclassical approach of field quantization in a black hole background, through the bootstrap condition. The density of states for both the quantum and thermal interpretation of the WKB formula are finally shown to differ quantitatively when including the non-local effects.

A computationally inexpensive method is presented for the recovery of spectra from measurements obtained with Hadamard transform spectrometers having nonideal masks. Normally, Nmeasurements are required in order to recover an N-point spectrum; this method requires N+ N0measurements to be taken, where, typically, N0≤ 10. Once the additional measurements have been taken, only O(N[log2N+ 2]) arithmetic operations—mostly additions or subtractions—are needed in order to recover the spectrum; a conventional procedure requires O(2N2) operations. Preliminary work for this method is minimal, requiring O(N) operations as opposed to O(N3) for a conventional procedure; this work needs to be done only once for a given spectrometer. The spectrum-estimate obtained is unbiased.

A spectrum-recovery method is presented which efficiently computes an optimal unbiased linear spectrum-estimate for measurements obtained with Hadamard transform (HT) spectrometers having nonideal masks. This method has the following advantages over other spectrum-recovery techniques: it is computationally efficient, it requires no additional measurements, and it computes an optimal spectrum-estimate. In the method presented, after the mask of the HT spectrometer has been characterized, approximately 3Npreliminary arithmetic operations are performed once for a given spectrometer, where Nis both the number of spectral resolution-elements desired and the number of measurements required. Each spectrum-estimate to be recovered then requires only an additional O[N(log2N+ 4)] arithmetic operations. In contrast, conventional methods for obtaining an optimal unbiased linear spectrum-estimate require O(N3) preliminary operations, and O(2N2) operations during each spectrum-recovery.

The multiplexing inherent in the Hadamard transform (HT) spectrometer can result in an improved spectrum-estimate when the detector is the major source of noise. A spectrum-estimate may be further improved by taking into account any nonidealities in the system. In this paper, observations concerning the errors associated with such estimates are presented, with the use of results obtained from computer simulations. Three spectrum-recovery techniques for an HT spectrometer having a nonideal electro-optic mask are considered in terms of the mean-square error (MSE) associated with a given estimate. The discussion of the MSE is with respect to the input spectrum to be estimated, the detector noise, the transmittances of the nonideal mask, and the use of coaddition. Included is a review of the computational efficiency and the statistical bias of each method. The relative performances of the spectrum-recovery methods are presented with examples to help identify the sources of error for each of the techniques.

Summary In the atrioventricular system (AVS) consisting of the compact node, the penetrating bundle and the branching bundles of about 250 bovine hearts there were made several studies:

The complexes of SO3with HF, HCl, and HBr have been studied by microwave spectroscopy. In all three systems, the halogen atom approaches the SO3on or near its C3axis, and the vibrationally averaged structure is that of a symmetric top. The S–X bond lengths are 2.655(10), 3.1328(57), and 3.2339(85) Å for the HF, HCl, and HBr complexes, respectively, and in all three systems the out-of-plane distortion of the SO3is negligible. In HF–SO3, the hydrogen points away from the SO3and hyperfine structure in the DF complex gives an average angle of 47.7° with respect to the vibrationally averaged C3axis of the complex. In the HCl and HBr complexes, however, the HX unit is nearly parallel to the SO3plane. In HCl–SO3, the HCl forms a 72.8° angle with the average C3axis of the complex, with the proton tilting slightly toward the SO3. In HBr–SO3, the average orientation of the HBr is 73.0° off the symmetry axis of the complex, but the direction of the tilt (toward or away from the SO3) is not determined. Although the hydrogen halides react with SO3in bulk to produce halosulfuric acids, these gas-phase complexes are much like weakly bound dimers.

Summary The influence of transforming growth factor-ß (TGF-ß) on hematopoiesis has been evaluated by adding blocking antibodies against TGF-ß to colony forming assays (CFU-c). When optimum concentrations of recombinant growth factors, granulocyte-macrophage colony stimulating factor (GM-CSF), and interleukin-3 (IL-3) were added to stem cells from the peripheral blood of healthy individuals and certain patients with tumors or HIV infection, the anti-TGF-ß capable of blocking 5 ng/ml of active TGF-ß had no significant influence on erythroid or myeloid colony formation. However, in certain immunosuppressed individuals, anti-TGF-ß resulted in a significant decrease of erythroid colony formation and slight suppression of myeloid colony formation. The significant inhibition of hematopoiesis by plasma of HIV patients could be due to the presence of active forms of TGF-ß. The results of the blocking experiments are consistent with the concept that TGF-ß in low concentrations is essential for erythropoiesis and myelopoiesis but that higher levels of TGF-ß primarily inhibit erythropoiesis in vitro. TGF-ß serves as a coordinating factor when efficient recruitment of granulocytes and monocytes is more essential than erythropoiesis and stem cell growth.

We summarize the radio synchrotron background workshop that took place 2017 July 19-21 at the University of Richmond. This first scientific meeting dedicated to the topic was convened because current measurements of the diffuse radio monopole reveal a surface brightness that is several times higher than can be straightforwardly explained by known Galactic and extragalactic sources and processes, rendering it by far the least well understood photon background at present. It was the conclusion of a majority of the participants that the radio monopole level is at or near that reported by the ARCADE 2 experiment and inferred from several absolutely calibrated zero-level lower frequency radio measurements, and unanimously agreed that the production of this level of surface brightness, if confirmed, represents a major outstanding question in astrophysics. The workshop reached a consensus on the next priorities for investigations of the radio synchrotron background.

The poem "The Tragedy of Courtney Love," by B. C. Harms is presented. First Line: Ascendant curtain; Last Line: And the Curtain falls.

Conclusions Low dose filgrastim in postoperative/posttraumatic patients at risk of and with sepsis may boost host defense by stimulating neutrophil function and simultaneously counteract progression of sepsis by improving an antiinflammatory cytokine response with protective effects on the endothelium.