1,833 research outputs found
A quantitative ecological study of selected nearshore marine plants and animals at the Diablo Canyon power plant site: a pre-operational baseline, 1973-1978
Biologists of the California Department of Fish and Game, under contract with the Pacific Gas and Electric Company, conducted surveys or intertidal and subtidal plants and animals 1n the vicinity of the Diablo Canyon Nuclear Power
Plant for the summer of 1973 through 1978. Abundances of the dominant plants and animals were obtained at random as well as permanent stations in Diablo Cove as well as nearby control areas. A total of 643 permanent and random stations were surveyed, 262 in the intertidal and 381 in the subtidal.
Natural as well as man-caused occurrences have resulted in several significant changes in plant and animal abundance in the study areas; these include the arrival of the southern front or the sea otter population in Diablo Cove in 1974; a strong red tide bloom in the fall of 1974; and the release of copper ions from the power plant condenser tubes into Diablo Cove during the summer of 1974.
Our intertidal and subtidal random station data have shown a strong decline in giant red sea urchin, Strongylocentrotus franciscanus, densities and the surface canopy kelp, Nereocystis/leutkeana, and a corresponding increase in the
subcanopy kelps, Pterygophora and Laminaria. Seasonal patterns of abundance of foliose red algae at random intertidal stations occurred at all study areas. Several species intertidal and subtidal invertebrates showed increasing or decreasing trends in levels of abundance during the five year study period covered by the report. Some of these changes in abundance may be related to
the natural man-caused impacts mentioned above. (Document has 728 pages
The U.S. Securities and Exchange Commission, Financial Institutions Outside the U.S. and Extraterritorial Application of the U.S. Securities Laws
The U.S. Securities and Exchange Commission, Financial Institutions Outside the U.S. and Extraterritorial Application of the U.S. Securities Laws
Filamentary Accretion Flows in the Embedded Serpens South Protocluster
One puzzle in understanding how stars form in clusters is the source of mass
-- is all of the mass in place before the first stars are born, or is there an
extended period when the cluster accretes material which can continuously fuel
the star formation process? We use a multi-line spectral survey of the southern
filament associated with the Serpens South embedded cluster-forming region in
order to determine if mass is accreting from the filament onto the cluster, and
whether the accretion rate is significant. Our analysis suggests that material
is flowing along the filament's long axis at a rate of ~30Msol/Myr (inferred
from the N2H+ velocity gradient along the filament), and radially contracting
onto the filament at ~130Msol/Myr (inferred from HNC self-absorption). These
accretion rates are sufficient to supply mass to the central cluster at a
similar rate to the current star formation rate in the cluster. Filamentary
accretion flows may therefore be very important in the ongoing evolution of
this cluster.Comment: 19 pages, 8 figures, 2 tables; accepted for publication in Ap
Network device interface for digitally interfacing data channels to a controller via a network
A communications system and method are provided for digitally connecting a plurality of data channels, such as sensors, actuators, and subsystems, to a controller using a network bus. The network device interface interprets commands and data received from the controller and polls the data channels in accordance with these commands. Specifically, the network device interface receives digital commands and data from the controller, and based on these commands and data, communicates with the data channels to either retrieve data in the case of a sensor or send data to activate an actuator. Data retrieved from the sensor is converted into digital signals and transmitted to the controller. Network device interfaces associated with different data channels can coordinate communications with the other interfaces based on either a transition in a command message sent by the bus controller or a synchronous clock signal
Network device interface for digitally interfacing data channels to a controller via a network
The present invention provides a network device interface and method for digitally connecting a plurality of data channels, such as sensors, actuators, and subsystems, to a controller using a network bus. The network device interface interprets commands and data received from the controller and polls the data channels in accordance with these commands. Specifically, the network device interface receives digital commands and data from the controller, and based on these commands and data, communicates with the data channels to either retrieve data in the case of a sensor or send data to activate an actuator. Data retrieved from the sensor is then converted by the network device interface into digital signals and transmitted back to the controller. In one advantageous embodiment, the network device interface uses a specialized protocol for communicating across the network bus that uses a low-level instruction set and has low overhead for data communication
Macrostates vs. Microstates in the Classical Simulation of Critical Phenomena in Quench Dynamics of 1D Ising Models
We study the tractability of classically simulating critical phenomena in the
quench dynamics of one-dimensional transverse field Ising models (TFIMs) using
highly truncated matrix product states (MPS). We focus on two paradigmatic
examples: a dynamical quantum phase transition (DQPT) that occurs in
nonintegrable long-range TFIMs, and the infinite-time correlation length of the
integrable nearest-neighbor TFIM when quenched to the critical point. For the
DQPT, we show that the order parameters can be efficiently simulated with
surprisingly heavy truncation of the MPS bond dimension. This can be used to
reliably extract critical properties of the phase transition, including
critical exponents, even when the full many-body state is not simulated with
high fidelity. The long-time correlation length near the critical point is more
sensitive to the full many-body state fidelity, and generally requires a large
bond dimension MPS. Nonetheless, we find that this can still be efficiently
simulated with strongly truncated MPS because it can be extracted from the
short-time behavior of the dynamics where entanglement is low. Our results
demonstrate that while accurate calculation of the full many-body state
(microstate) is typically intractable due to the volume-law growth of
entanglement, a precise specification of an exact microstate may not be
required when simulating phases of matter of many-body systems (macrostates).
We also study the tractability of simulation using truncated MPS based on
quantum chaos and equilibration in the models. We find a counterintuitive
inverse relationship, whereby local expectation values are most easily
approximated for chaotic systems whose exact many-body state is most
intractable.Comment: 6 sections, 4 appendices, 19 figure
ELF3 controls thermoresponsive growth in Arabidopsis
Plant development is highly responsive to ambient temperature, and this trait has been linked to the ability of plants to adapt to climate change [1]. The mechanisms by which natural populations modulate their thermoresponsiveness are not known [2]. To address this, we surveyed Arabidopsis accessions for variation in thermal responsiveness of elongation growth and mapped the corresponding loci. We find that the transcriptional regulator EARLY FLOWERING3 (ELF3) controls elongation growth in response to temperature. Through a combination of modeling and experiments, we show that high temperature relieves the gating of growth at night, highlighting the importance of temperature-dependent repressors of growth. ELF3 gating of transcriptional targets responds rapidly and reversibly to changes in temperature. We show that the binding of ELF3 to target promoters is temperature dependent, suggesting a mechanism where temperature directly controls ELF3 activity
- …