5,582 research outputs found
Including food systems, biodiversity, nutrition and health in the Post-2020 Global Biodiversity Framework: a submission from the Alliance of Bioversity International and the International Center for Tropical Agriculture.
Meeting Wastewater Discharge Standards by Use of High-Rate Infiltration-Percolation Basins
Two fundamental problems have been associated with the use of large quantities of water – depletion and deterioration in quality. Present advanced wastewater treatment technology has shown that tertiary treatment of wastewater can produce high quality effluents, but large amounts of energy and chemicals must be sacrificed. An alternative to these costly systems is the land treatment system, which utilizes the soil mantle as a multiprocess “living filter” (2). Infiltration-percolation, a land treatment method, can be used for the reclamation of large quantities of wastewater. The infiltration-percolation advance treatment system has been investigated extensively by the Civil Engineering Department at South Dakota State University. South Dakota’s predominantly rural environment makes land treatment a conductive method of advanced wastewater treatment. Initial investigations that considered the soil matrix as a treatment system began with research conducted by Druyvestein (3). Examination of water leaking through the bottom of the Volga, Milbank and Beresford, South Dakota stabilization ponds resulted in the conclusion that good quality water could be obtained by passing stabilization pond effluent through the soil. Further studies using soil lysimeters produced a good quality effluent, but infiltration rates were too low to make the system practical (4, 5)
Magellanic Cloud Periphery Carbon Stars IV: The SMC
The kinematics of 150 carbon stars observed at moderate dispersion on the
periphery of the Small Magellanic Cloud are compared with the motions of
neutral hydrogen and early type stars in the Inter-Cloud region. The
distribution of radial velocities implies a configuration of these stars as a
sheet inclined at 73+/-4 degrees to the plane of the sky. The near side, to the
South, is dominated by a stellar component; to the North, the far side contains
fewer carbon stars, and is dominated by the neutral gas. The upper velocity
envelope of the stars is closely the same as that of the gas. This
configuration is shown to be consistent with the known extension of the SMC
along the line of sight, and is attributed to a tidally induced disruption of
the SMC that originated in a close encounter with the LMC some 0.3 to 0.4 Gyr
ago. The dearth of gas on the near side of the sheet is attributed to ablation
processes akin to those inferred by Weiner & Williams (1996) to collisional
excitation of the leading edges of Magellanic Stream clouds. Comparison with
pre LMC/SMC encounter kinematic data of Hardy, Suntzeff, & Azzopardi (1989) of
carbon stars, with data of stars formed after the encounter, of Maurice et al.
(1989), and Mathewson et al. (a986, 1988) leaves little doubt that forces other
than gravity play a role in the dynamics of the H I.Comment: 30 pages; 7 figures, latex compiled, 1 table; to appear in AJ (June
2000
Kerberoasting: Case Studies of an Attack on a Cryptographic Authentication Technology
Kerberoasting, an attack vector aimed at the Kerberos authentication protocol, can be used as part of an adversary’s attack arsenal. Kerberos is a type of network authentication protocol that allows a client and server to conduct a mutual verification before providing the requested resource to the client. A successful Kerberoasting attack allows an adversary to leverage the architectural limitations of Kerberos, providing access to user password hashes that can be subject to offline cracking. A cracked user password could give a bad actor the ability to maintain persistence, move laterally, or escalate privileges in a system. Persistence or movement within a system is indispensable to a bad actor. Adversaries may use Kerberoasting to achieve this persistence or movement as part of a more effective attack. These attacks can include ransomware, stealthy removal of data from a system, or building a back door for future access. It is, therefore, vital to understand how Kerberoasting works to detect attacks and mitigate future attempts. We examine cases in which Kerberoasting has played a role in an attack or was used as a tool in an adversary’s arsenal and review the outcomes. We then discuss known ways to detect and mitigate Kerberoasting attacks and analyze how this information can inform enterprise policy
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Neutrophil extracellular traps
Cancers prime neutrophils to release extracellular DNA traps through the systemic release of granulocyte colony-stimulating factor (G-CSF). We recently showed that these circulating neutrophil extracellular traps (NETs) promote the establishment of a pro-thrombotic state. The role of NETs in cancer biology and tumor progression may prove much more than an unfortunate side effect of cancer
RR Lyrae stars in four globular clusters in the Fornax dwarf galaxy
(Abridged) We have surveyed four globular clusters in the Fornax dwarf galaxy
for RR Lyrae stars, using archival HST observations. We identify 197 new RR
Lyrae stars in these four clusters. Despite the short observational baseline,
we derive periods, light-curves, and photometric parameters for each. The
Fornax clusters have exceptionally large RR Lyrae specific frequencies compared
with the Galactic globular clusters. Furthermore, the Fornax cluster RR Lyrae
stars are unusual in that their characteristics are intermediate between the
two Galactic Oosterhoff groups. In this respect the Fornax clusters are similar
to the field populations in several dwarf galaxies. We revise previous
measurements of the HB morphology in each cluster. The Fornax clusters closely
resemble the ``young'' Galactic halo population defined by Zinn. The existence
of the second parameter effect among the Fornax clusters is also confirmed.
Finally, we determine foreground reddening and distance estimates for each
cluster. We find a mean distance modulus to Fornax of (m-M)_0 = 20.66 +/- 0.03
(random) +/- 0.15 (systematic). Our measurements are consistent with a line of
sight depth of 8-10 kpc for this galaxy, matching its projected dimensions, and
incompatible with tidal model explanations for the observed high velocity
dispersions in many dSph galaxies. Dark matter dominance is suggested.Comment: 26 pages, 6 figures. Accepted for publication in MNRAS. Table 2 and
Figure 2 will only be available in the electronic version. On-line data will
soon be available at http://www.ast.cam.ac.uk/STELLARPOPS/Fornax_RRlyr
Mercury mobilization and episodic stream acidification during snowmelt: Role of hydrologic flow paths, source areas, and supply of dissolved organic carbon
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95317/1/wrcr11826.pd
Media outlets and their moguls: why concentrated individual or family ownership is bad for editorial independence
This article investigates the levels of owner influence in 211 different print and broadcast outlets in 32 different European media markets. Drawing on the literature from industrial organisation, it sets out reasons why we should expect greater levels of influence where ownership of individual outlets is concentrated; where it is concentrated in the hands of individuals or families; and where ownership groups own multiple outlets in the same media market. Conversely, we should expect lower levels of influence where ownership is dispersed between transnational companies. The articles uses original data on the ownership structures of these outlets, and combines it with reliable expert judgments as to the level of owner influence in each of the outlets. These hypotheses are tested and confirmed in a multilevel regression model of owner influence. The findings are relevant for policy on ownership limits in the media, and for the debate over transnational versus local control of media
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Nonmalignant respiratory disease mortality among woodworkers participating in the American Cancer Society Cancer Prevention Study-II (CPS-II)
Nonmalignant respiratory disease (NMRD) mortality was examined among woodworkers participating in the American Cancer Society’s CPS-II cohort study. During the 6-year prospective follow-up, there were 97 NMRD deaths among 11,541 men reporting employment in wood-related occupations and 1,338 NMRD deaths among 317,424 men reporting no exposure to wood dust or wood-related jobs. Relative risks, adjusted for age and smoking, were calculated using Poisson regression. A small excess of NMRD was observed among woodworkers. However, the relative risk was higher among woodworkers who did not report exposure to wood dust (RR = 1.52, 95% CI = 1.18–1.97) than those who did (RR = 1.27, 95% CI = 0.91–1.77), and no clear trend with duration of exposure was observed. An excess of NMRD was observed among woodworkers reporting exposure to asbestos (RR = 1.59, 95% CI = 0.85–2.96), as well as the small number of woodworkers reporting exposure to formaldehyde (RR = 1.95, 95% CI = 0.63–6.06), but men not reporting exposure to these substances also had an excess risk. Although limited by a short follow-up period and crude indicators of exposure, the strengths of this analysis were the ability to compare woodworkers to a similar, healthy population and to adjust for the effects of smoking. Cohort studies with better exposure information are needed to examine the role of occupational exposures among woodworkers in the etiology of respiratory disease
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