84 research outputs found
Probiotic fertilizers
Presented at Irrigation and water resources in the 1990's: proceedings from the 1992 national conference held on October 5-7, 1992 in Phoenix, Arizona.Includes bibliographical references.Since the advent of chemical fertilizers there has been a loss of humus in most agricultural soils and a diminishing of the vital biological dynamics which were present in less intensive chemical farming. The loss of healthy top soil is well documented. Salt problems are significant in virtually all irrigation areas, and the deterioration of soil structure with resulting reduction of irrigation efficiency is well-known. Probiotic technology, which takes into account the biological potential of soils, can reverse these trends and enables the farmer to use "environmentally friendly" fertilizers which restore and build healthy soil by increasing the humus complexes in soils. The dramatic change in soil structure improves water infiltration and water release efficiency, and buffers harmful salts in water and soil. University research has shown that nitrate fertilizers can be maintained in the root zone with less leaching of nitrate and other agrichemicals due to biological complexing and chelation. Probiotic technology enhances the natural processes in the soil while biodegrading the detrimental chemical residue that has accumulated in soil. Humus is a biological soil derivative which has received insufficient research attention. The pressure to develop high production agriculture utilizing salt-based fertilizers and a host of chemicals has been the focus of most agricultural research. The residual of many of these compounds has been detrimental to the health and vitality of the natural biological systems. Soil conditions have generally deteriorated. This deterioration contributes to erosion which is responsible for significant losses in fertile soil every year
Superficial simplicity of the 2010 El Mayor–Cucapah earthquake of Baja California in Mexico
The geometry of faults is usually thought to be more complicated at the surface than at depth and to control the initiation, propagation and arrest of seismic ruptures. The fault system that runs from southern California into Mexico is a simple strike-slip boundary: the west side of California and Mexico moves northwards with respect to the east. However, the M_w 7.2 2010 El Mayor–Cucapah earthquake on this fault system produced a pattern of seismic waves that indicates a far more complex source than slip on a planar strike-slip fault. Here we use geodetic, remote-sensing and seismological data to reconstruct the fault geometry and history of slip during this earthquake. We find that the earthquake produced a straight 120-km-long fault trace that cut through the Cucapah mountain range and across the Colorado River delta. However, at depth, the fault is made up of two different segments connected by a small extensional fault. Both segments strike N130° E, but dip in opposite directions. The earthquake was initiated on the connecting extensional fault and 15 s later ruptured the two main segments with dominantly strike-slip motion. We show that complexities in the fault geometry at depth explain well the complex pattern of radiated seismic waves. We conclude that the location and detailed characteristics of the earthquake could not have been anticipated on the basis of observations of surface geology alone
Post-fire vegetation dynamics of a sagebrush steppe community change significantly over time
Sagebrush steppe ecosystems of the Intermountain West have experienced a decline over
the past 150 years due to changing fire regimes, invasive species and conifer encroachment.
Prescribed fire is a common and cost-effective tool used in sagebrush restoration
and fuels management. We examined the post-fire succession of a sagebrush steppe community
over a nearly 30-year period at two study sites in northeastern California. The long-term
nature of this study was particularly significant, as invasive annual grasses dominated
the plant community in the years immediately following fire, but native perennial
grasses and shrubs successfully out-competed them in the long term. Shrubs were slow
to recover but had returned to pre-fire levels by the end of the study period. There
was also notable increase in western juniper throughout the study sites, particularly
in areas that had not been burned. Our results indicate that mean fire return intervals
of 50 years or less would help reduce western juniper encroachment and preserve sagebrush
habitat, especially for potentially threatened species such as the sage grouse
B-lymphocyte stimulator/a proliferation-inducing ligand heterotrimers are elevated in the sera of patients with autoimmune disease and are neutralized by atacicept and B-cell maturation antigen-immunoglobulin
Abstract Introduction B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL) are members of the tumor necrosis factor (TNF) family that regulate B-cell maturation, survival, and function. They are overexpressed in a variety of autoimmune diseases and reportedly exist in vivo not only as homotrimers, but also as BLyS/APRIL heterotrimers. Methods A proprietary N-terminal trimerization domain was used to produce recombinant BLyS/APRIL heterotrimers. Heterotrimer biologic activity was compared with that of BLyS and APRIL in a 4-hour signaling assay by using transmembrane activator and CAML interactor (TACI)-transfected Jurkat cells and in a 4-day primary human B-cell proliferation assay. A bead-based immunoassay was developed to quantify native heterotrimers in human sera from healthy donors (n = 89) and patients with systemic lupus erythematosus (SLE; n = 89) or rheumatoid arthritis (RA; n = 30). Heterotrimer levels were compared with BLyS and APRIL homotrimer levels in a subset of these samples. Results The recombinant heterotrimers consisted mostly of one BLyS and two APRIL molecules. Heterotrimer signaling did not show any significant difference compared with APRIL in the TACI-Jurkat assay. Heterotrimers were less-potent inducers of B-cell proliferation than were homotrimeric BLyS or APRIL (EC50, nMol/L: BLyS, 0.02; APRIL, 0.17; heterotrimers, 4.06). The soluble receptor fusion proteins atacicept and B-cell maturation antigen (BCMA)-immunoglobulin (Ig) neutralized the activity of BLyS, APRIL, and heterotrimers in both cellular assays, whereas B-cell activating factor belonging to the TNF family receptor (BAFF-R)-Ig neutralized only the activity of BLyS. In human sera, significantly more patients with SLE had detectable BLyS (67% versus 18%; P < 0.0001), APRIL (38% versus 3%; P < 0.0002), and heterotrimer (27% versus 8%; P = 0.0013) levels compared with healthy donors. Significantly more patients with RA had detectable APRIL, but not BLyS or heterotrimer, levels compared with healthy donors (83% versus 3%; P < 0.0001). Heterotrimer levels weakly correlated with BLyS, but not APRIL, levels. Conclusions Recombinant BLyS/APRIL heterotrimers have biologic activity and are inhibited by atacicept and BCMA-Ig, but not by BAFF-R-Ig. A novel immunoassay demonstrated that native BLyS/APRIL heterotrimers, as well as BLyS and APRIL homotrimers, are elevated in patients with autoimmune diseases
Clear-sky closure studies of lower tropospheric aerosol and water vapor during ACE-2 using airborne sunphotometer, airborne in-situ, space-borne, and ground-based measurements
We report on clear-sky column closure experiments (CLEARCOLUMN) performed in the Canary Islands during the second Aerosol Characterization Experiment (ACE-2) in June/July 1997. We present CLEARCOLUMN results obtained by combining airborne sunphotometer and in-situ (optical particle counter, nephelometer, and absorption photometer) measurements taken aboard the Pelican aircraft, space-borne NOAA/AVHRR data and ground-based lidar and sunphotometer measurements. During both days discussed here, vertical profiles flown in cloud-free air masses revealed 3 distinctly different layers: a marine boundary layer (MBL) with varying pollution levels, an elevated dust layer, and a very clean layer between the MBL and the dust layer. A key result of this study is the achievement of closure between extinction or layer aerosol optical depth (AOD) computed from continuous in-situ aerosol size-distributions and composition and those measured with the airborne sunphotometer. In the dust, the agreement in layer AOD (λ=380–1060 nm) is 3–8%. In the MBL there is a tendency for the in-situ results to be slightly lower than the sunphotometer measurements (10–17% at λ=525 nm), but these differences are within the combined error bars of the measurements and computations
Ernst Freund as Precursor of the Rational Study of Corporate Law
Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe
Spatial Variability of Turbulent Fluxes in the Roughness Sublayer of an Even-Aged Pine Forest
The spatial variability of turbulent flow statistics in the roughness sublayer (RSL) of a uniform even-aged 14 m (= h) tall loblolly pine forest was investigated experimentally. Using seven existing walkup towers at this stand, high frequency velocity, temperature, water vapour and carbon dioxide concentrations were measured at 15.5 m above the ground surface from October 6 to 10 in 1997. These seven towers were separated by at least 100m from each other. The objective of this study was to examine whether single tower turbulence statistics measurements represent the flow properties of RSL turbulence above a uniform even-aged managed loblolly pine forest as a best-case scenario for natural forested ecosystems. From the intensive space-time series measurements, it was demonstrated that standard deviations of longitudinal and vertical velocities (σ u , σ w ) and temperature (σ T ) are more planar homogeneous than their vertical flux of momentum (u * 2 ) and sensible heat (H) counterparts. Also, the measured H is more horizontally homogeneous when compared to fluxes of other scalar entities such as CO 2 and water vapour. While the spatial variability in fluxes was significant (>15 %), this unique data set confirmed that single tower measurements represent the ‘canonical’ structure of single-point RSL turbulence statistics, especially flux-variance relationships. Implications to extending the ‘moving-equilibrium’ hypothesis for RSL flows are discussed. The spatial variability in all RSL flow variables was not constant in time and varied strongly with spatially averaged friction velocity u * , especially when u * was small. It is shown that flow properties derived from two-point temporal statistics such as correlation functions are more sensitive to local variability in leaf area density when compared to single point flow statistics. Specifically, that the local relationship between the reciprocal of the vertical velocity integral time scale (I w ) and the arrival frequency of organized structures (ū/h) predicted from a mixing-layer theory exhibited dependence on the local leaf area index. The broader implications of these findings to the measurement and modelling of RSL flows are also discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42512/1/10546_2004_Article_234383.pd
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