242 research outputs found
Potential Environmental Contamination From Conventional and Alternative Cropping Systems in Northeast Kansas
Surface-water contamination from agricultural chemicals is a problem in northeast Kansas. The objective of this study is to compare potential atrazine, nitrogen, and sediment loadings from regional conventional and alternative cropping systems. Results indicate that several alternative systems have lower loading levels for atrazine and sediment than the conventional system, but higher loading levels for nitrogenalternative agriculture, nitrogen, atrazine, Crop Production/Industries, Environmental Economics and Policy,
Student Expectations and Preferences of Distance Course Delivery Methods
Students in five courses offered with a variety of distance and on-campus delivery methods were surveyed to determine student expectations and post-evaluation of courses; student demographics; and student experiences and preferences with technology and course delivery methods. The response group was primarily degree seeking upperclassmen, taking a required course, equally split by gender and by delivery location. All students preferred a live class delivery method but videotape delivery appeared to have a higher student satisfaction level than satellite. On-campus students found simultaneous satellite delivery distracting but not detrimental to their learning experience. Students consistently misjudged the content and workload of courses.Teaching/Communication/Extension/Profession,
An Economic Analysis of the IFMPO
The Integrated Farm Management Program Option (IFMPO) of the 1990 farm bill is designed to increase crop management flexibility and promote the use of resource-conserving crops. Economic analysis of this program indicates that, although the current format provides flexibility, it provides little economic incentive to adopt resource-conserving crop rotations.Farm Management,
An Economic Comparison of Composted Manure and Commercial Nitrogen with Imperfect Information
The economic feasibility of fertilizing irrigated grain sorghum with compos ted manure is evaluated using net return budgeting and production function analysis. Although the use of compost is technically feasible, the economic analysis indicates that compost does not comprise a large percentage of the nitrogen source in the profit-maximizing combination with commercial fertilizer.Composted manure, commercial nitrogen, net returns budgeting, production function analysis, irrigated grain sorghum, Crop Production/Industries,
Mode-multiplexing deep-strong light-matter coupling
Dressing quantum states of matter with virtual photons can create exotic
effects ranging from vacuum-field modified transport to polaritonic chemistry,
and may drive strong squeezing or entanglement of light and matter modes. The
established paradigm of cavity quantum electrodynamics focuses on resonant
light-matter interaction to maximize the coupling strength
, defined as the ratio of the vacuum Rabi
frequency and the carrier frequency of light. Yet, the finite oscillator
strength of a single electronic excitation sets a natural limit to
. Here, we demonstrate a new regime of
record-strong light-matter interaction which exploits the cooperative dipole
moments of multiple, highly non-resonant magnetoplasmon modes specifically
tailored by our metasurface. This multi-mode coupling creates an ultrabroadband
spectrum of over 20 polaritons spanning 6 optical octaves, vacuum ground state
populations exceeding 1 virtual excitation quantum for electronic and optical
modes, and record coupling strengths equivalent to
. The extreme interaction drives
strongly subcycle exchange of vacuum energy between multiple bosonic modes akin
to high-order nonlinearities otherwise reserved to strong-field physics, and
entangles previously orthogonal electronic excitations solely via vacuum
fluctuations of the common cavity mode. This offers avenues towards tailoring
phase transitions by coupling otherwise non-interacting modes, merely by
shaping the dielectric environment
Ultrafast terahertz saturable absorbers using tailored intersubband polaritons
Semiconductor heterostructures have enabled a great variety of applications ranging from GHz electronics to photonic quantum devices. While nonlinearities play a central role for cutting-edge functionality, they require strong field amplitudes owing to the weak light-matter coupling of electronic resonances of naturally occurring materials. Here, we ultrastrongly couple intersubband transitions of semiconductor quantum wells to the photonic mode of a metallic cavity in order to custom-tailor the population and polarization dynamics of intersubband cavity polaritons in the saturation regime. Two-dimensional THz spectroscopy reveals strong subcycle nonlinearities including six-wave mixing and a collapse of light-matter coupling within 900 fs. This collapse bleaches the absorption, at a peak intensity one order of magnitude lower than previous all-integrated approaches and well achievable by state-of-the-art QCLs, as demonstrated by a saturation of the structure under cw-excitation. We complement our data by a quantitative theory. Our results highlight a path towards passively mode-locked QCLs based on polaritonic saturable absorbers in a monolithic single-chip design
Validation of a model-based inverse kinematics approach based on wearable inertial sensors
Wearable inertial measurement units (IMUs) are a promising solution to human motion estimation. Using IMUs 3D orientations, a model-driven inverse kinematics methodology to estimate joint angles is presented. Estimated joint angles were validated against encoder-measured kinematics (robot) and against marker-based kinematics (passive mechanism). Results are promising, with RMS angular errors respectively lower than 3 and 6 deg over a minimum range of motion of 50 deg (robot) and 160 deg (passive mechanism). Moreover, a noise robustness analysis revealed that the model-driven approach reduces the effects of experimental noises, making the proposed technique particularly suitable for application in human motion analysis
Second Backbend in the Mass A ~ 180 Region
Within the framework of selfconsistent cranked Hartree-Fock- Bogoliubov
theory(one-dimensional) we predict second backbend in the yrast line of Os-182
at , which is even sharper than the first one observed
experimentally at .
Around such a high spin the structure becomes multi-quasiparticle type, but
the main source of this strong discontinuity is a sudden large alignment of
i_13/2 proton orbitals along the rotation axis followed soon by the alignment
of j_15/2 neutron orbitals. This leads to drastic structural changes at such
high spins. When experimentally confirmed, this will be observed for the first
time in this mass region, and will be at the highest spin so far.Comment: 13 pages, 4 ps figure
Prospective Evaluation of Thoracic Ultrasound in the Detection of Pneumothorax
Introduction: Pneumothorax (PTX) occurs commonly in trauma patients and is confirmed by examination and radiography. Thoracic ultrasound (VIS) has been suggested as an alternative method for rapidly diagnosing PTX when X-ray is unavailable as in rural, military, or space flight settings; however, its accuracy and specificity are not known. Methods: We evaluated the accuracy of thoracic U/S detection of PTX compared to radiography in stable, emergency patients with a high suspicion of PTX at a Level-l trauma center over a 6-month period. Following University and NASA Institutional Review Board approval, informed consent was obtained from patients with penetrating or blunt chest trauma, or with a history consistent with PTX. Whenever possible, the presence or absence of the " lung sliding" sign or the "comet tail" artifact were determined by U/S in both hemithoraces by residents instructed in thoracic U/S before standard radiologic verification of PTX. Results were recorded on data sheets for comparison to standard radiography. Results: Thoracic VIS had a 94% sensitivity; two PTX could not be reliably diagnosed due to subcutaneous air; the true negative rate was 100%. In one patient, the VIS exam was positive while X ray did not confirm PTX; a follow-up film 1 hour later demonstrated a small PTX. The average time for bilateral thoracic VIS examination was 2 to 3 minutes. Conclusions: Thoracic ultrasound reliably diagnoses pneumothorax. Presence of the "lung sliding" sign conclusively excludes pneumothorax. Expansion of the FAST examination to include the thorax should be investigated
Au-Ag template stripped pattern for scanning probe investigations of DNA arrays produced by Dip Pen Nanolithography
We report on DNA arrays produced by Dip Pen Nanolithography (DPN) on a novel
Au-Ag micro patterned template stripped surface. DNA arrays have been
investigated by atomic force microscopy (AFM) and scanning tunnelling
microscopy (STM) showing that the patterned template stripped substrate enables
easy retrieval of the DPN-functionalized zone with a standard optical
microscope permitting a multi-instrument and multi-technique local detection
and analysis. Moreover the smooth surface of the Au squares (abput 5-10
angstrom roughness) allows to be sensitive to the hybridization of the
oligonucleotide array with label-free target DNA. Our Au-Ag substrates,
combining the retrieving capabilities of the patterned surface with the
smoothness of the template stripped technique, are candidates for the
investigation of DPN nanostructures and for the development of label free
detection methods for DNA nanoarrays based on the use of scanning probes.Comment: Langmuir (accepted
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