3,034 research outputs found
Environmental Responsibilities Overseas: The National Environmental Policy Act and the Export-Import Bank
The National Environmental Policy Act (NEPA) serves to regulate the environmental impacts of the activities of federal agencies. One such agency, the Export-Import Bank, aids the growth of United States exports in international markets by funding projects where private banks are unwilling. The courts have been selective in applying NEPA requirements to extraterritorial U.S. activities, but the Ex-Im Bank’s activities fall within the categories created by prior cases. Therefore, the Ex-Im Bank should apply NEPA to the projects it considers for funding
GREENHOUSE GAS METHANE AND NITROUS OXIDE PRODUCTION AND MIRCOBIAL FUNCTIONING GENE CHARACTERIZATION IN GRASSLANDS AND THE INFLUENCES BY GRAZING LAND MANAGEMENT
Methane and nitrous oxide gases are significantly more potent in their ability to create a greenhouse effect than CO2. Grazing lands can either be a sink or source of GHG depending on management scenarios and climatic conditions. Management of grasslands can have a broad impact on the levels of GHG emissions, as grazing pressure, crop rotations, and levels and types of fertilization inputs can alter microbial communities and influence on GHG production. Methanogens and denitrifying microbial communities are two major groups associated with the production of GHGs. This study attempted to unravel the microbial and geochemical characteristics associated with CH4 and N2O production, and the interplay between the grazing pressure and the fertilizer amendments in the nitrogen fixing clover and nitrate supplemented rye cover grasslands. Using GC analysis of incubated soil samples, this study indicated that surficial soils (0-8 cm) in both clover and rye grasslands contributed the highest production of CH4 and N2O. CH4 production showed significant seasonal changes. High levels of grazing intensity caused a significantly increased CH4 yield, which was particularly true with no nitrogen fertilized lands. Quantitative PCR of methyl coenzyme M reductase (mcrA) gene, one of the genes for methanogenesis pathway, further confirmed theses effects. Increased amendment of nitrogen and carbon of these soils showed that nitrate addition at 100 kg ha-1 after 9 day incubation stimulated CH4 production. Higher nitrate addition, however, could initially suppress methanogenic activities. Organic carbon additions also significantly enhanced CH4 production
Offshore Investments
This paper presents a study about offshore investments. It offers a broad analysis of the most popular structures used to carry those investments, the reasons why individuals and corporations choose this path and places that offer benefits for foreign investors. It also presents a discussion about the point of view of some international organizations regarding the use of offshore jurisdictions. Since the author is from Brazil, a brief description of the Brazilian laws for investors that go offshore is included in addition to the American laws. The work experience of the author with the subject was a good source of information to conclude that the benefits that can be obtained by the use of offshore entities depend on a number of factors, including the investor’s objectives, residency or citizenship, as well as the countries in which the entity will be doing business and that the offshore world will have to put in practice new procedures to keep the offshore industry alive, because of the many recent international reports
Sensory Motor Remapping of Space in Human-Machine Interfaces
Studies of adaptation to patterns of deterministic forces have revealed the ability of the motor control system to form and use predictive representations of the environment. These studies have also pointed out that adaptation to novel dynamics is aimed at preserving the trajectories of a controlled endpoint, either the hand of a subject or a transported object. We review some of these experiments and present more recent studies aimed at understanding how the motor system forms representations of the physical space in which actions take place. An extensive line of investigations in visual information processing has dealt with the issue of how the Euclidean properties of space are recovered from visual signals that do not appear to possess these properties. The same question is addressed here in the context of motor behavior and motor learning by observing how people remap hand gestures and body motions that control the state of an external device. We present some theoretical considerations and experimental evidence about the ability of the nervous system to create novel patterns of coordination that are consistent with the representation of extrapersonal space. We also discuss the perspective of endowing human–machine interfaces with learning algorithms that, combined with human learning, may facilitate the control of powered wheelchairs and other assistive devices
Systematic and Stochastic Variations in Pulsar Dispersion Measures
We analyze deterministic and random temporal variations in dispersion measure
(DM) from the full three-dimensional velocities of pulsars with respect to the
solar system, combined with electron-density variations on a wide range of
length scales. Previous treatments have largely ignored the pulsar's changing
distance while favoring interpretations involving the change in sky position
from transverse motion. Linear trends in pulsar DMs seen over 5-10~year
timescales may signify sizable DM gradients in the interstellar medium (ISM)
sampled by the changing direction of the line of sight to the pulsar. We show
that motions parallel to the line of sight can also account for linear trends,
for the apparent excess of DM variance over that extrapolated from
scintillation measurements, and for the apparent non-Kolmogorov scalings of DM
structure functions inferred in some cases. Pulsar motions through atomic gas
may produce bow-shock ionized gas that also contributes to DM variations. We
discuss possible causes of periodic or quasi-periodic changes in DM, including
seasonal changes in the ionosphere, annual variation of the solar elongation
angle, structure in the heliosphere-ISM boundary, and substructure in the ISM.
We assess the solar cycle's role on the amplitude of ionospheric and solar-wind
variations. Interstellar refraction can produce cyclic timing variations from
the error in transforming arrival times to the solar system barycenter. We
apply our methods to DM time series and DM gradient measurements in the
literature and assess consistency with a Kolmogorov medium. Finally, we discuss
the implications of DM modeling in precision pulsar timing experiments.Comment: 24 pages, 17 figures, published in Ap
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