2,791 research outputs found
Blast Those Stuumps!
You can get rid of troublesome stumps around your farm by blasting with dynamite. The coast isn\u27t large, but there are precautions to take
Tile and surface drainage of clay soils . II. Hydrologic performance with field crops (1962-72). III. Corn, oats, and soybean yields (1962-72)
Research on irrigation of corn and soybeans at Conesville and Ankeny, Iowa, 1951 to 1955
Irrigation in the humid and semihumid sections of the United States has increased manyfold since World War II. Before this, irrigation was confined principally to the more arid western states. Some of the reasons for the spread to more humid areas were the development of portable lightweight aluminum pipe and couplers, moderately high farm prices, occurrence of several drouthy seasons, increased use of fertilizers and development of better crop varieties. Drouths in various portions of the state in 1953, 1954, 1955 and 1956 have prompted many farmers to buy irrigation equipment. A 1953 survey in Iowa showed that only 55 farmers were irrigating about 3,600 acres. Twenty-two of these farmers were in Muscatine County where irrigation is used on vegetable crops. Two years later, in 1955, another survey indicated that 250 farmers were irrigating approximately 15,000 acres.
Indications are that irrigation will continue to increase, particularly along the Mississippi and Missouri rivers. Along the Missouri River there are about 600,000 acres of bottomland. Most of this area needs better surface drainage. Without too much additional cost, land which is surface drained can be shaped for surface irrigation. Because of good ground water supplies, this area has a high irrigation potential. These conditions also exist to a more limited extent along other major Iowa streams
Sparse Deterministic Approximation of Bayesian Inverse Problems
We present a parametric deterministic formulation of Bayesian inverse
problems with input parameter from infinite dimensional, separable Banach
spaces. In this formulation, the forward problems are parametric, deterministic
elliptic partial differential equations, and the inverse problem is to
determine the unknown, parametric deterministic coefficients from noisy
observations comprising linear functionals of the solution.
We prove a generalized polynomial chaos representation of the posterior
density with respect to the prior measure, given noisy observational data. We
analyze the sparsity of the posterior density in terms of the summability of
the input data's coefficient sequence. To this end, we estimate the
fluctuations in the prior. We exhibit sufficient conditions on the prior model
in order for approximations of the posterior density to converge at a given
algebraic rate, in terms of the number of unknowns appearing in the
parameteric representation of the prior measure. Similar sparsity and
approximation results are also exhibited for the solution and covariance of the
elliptic partial differential equation under the posterior. These results then
form the basis for efficient uncertainty quantification, in the presence of
data with noise
Spin-orbit coupling in a Quantum Dot at high magnetic field
We describe the simultaneous effects of the spin-orbit (SO) perturbation and
a magnetic field on a disk shaped quantum dot (QD). {As it is known the}
combination of electrostatic forces among the electrons confined in the QD
and the Pauli principle can induce a spin polarization when (applied in the
direction orthogonal to the QD) is above a threshold value. In the presence of
an electric field parallel to , coupled to the spin by a Rashba term,
we demonstrate that a symmetry breaking takes place: we can observe it by
analyzing the splitting of the levels belonging to an unperturbed multiplet. We
also discuss the competitive effects of the magnetic field, the SO perturbation
and the electron electron interaction, in order to define the hierarchy of the
states belonging to a multiplet. We demonstrate how this hierarchy depends on
the QD's size. We show the spin texture due to the combined effects of the
Rashba effect and the interaction responsible for the polarization.Comment: 8 pages, 3 figures, PACS: 73.21.La,71.15.Mb,75.75.+
MTSS1 is a critical epigenetically regulated tumor suppressor in CML
Chronic myeloid leukemia (CML) is driven by malignant stem cells that can persist despite therapy. We have identified Metastasis suppressor 1 (Mtss1/MIM) to be downregulated in hematopoietic stem and progenitor cells from leukemic transgenic SCLtTA/Bcr-Abl mice and in patients with CML at diagnosis, and Mtss1 was restored when patients achieved complete remission. Forced expression of Mtss1 decreased clonogenic capacity and motility of murine myeloid progenitor cells and reduced tumor growth. Viral transduction of Mtss1 into lineage depleted SCLtTA/Bcr-Abl bone marrow cells decreased leukemic cell burden in recipients, and leukemogenesis was reduced upon injection of Mtss1 overexpressing murine myeloid 32D cells. Tyrosine kinase inhibitor (TKI) therapy and reversion of Bcr-Abl expression increased Mtss1 expression but failed to restore it to control levels. CML patient samples revealed higher DNA methylation of specific Mtss1 promoter CpG sites that contain binding sites for Kaiso and Rest transcription factors. In summary, we identified a novel tumor suppressor in CML stem cells that is downregulated by both Bcr-Abl kinase-dependent and -independent mechanisms. Restored Mtss1 expression markedly inhibits primitive leukemic cell biology in vivo, providing a therapeutic rationale for the Bcr-Abl-Mtss1 axis to target TKI resistant CML stem cells in patients
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Clinically Significant Thromboembolic Disease in Adult Spinal Deformity Surgery: Incidence and Risk Factors in 737 Patients.
Study Design:Retrospective cohort study. Objectives:Describe the rate and risk factors for venous thromboembolic events (VTEs; defined as deep venous thrombosis [DVT] and/or pulmonary embolism [PE]) in adult spinal deformity (ASD) surgery. Methods:ASD patients with VTE were identified in a prospective, multicenter database. Complications, revision, and mortality rate were examined. Patient demographics, operative details, and radiographic and clinical outcomes were compared with a non-VTE group. Multivariate binary regression model was used to identify predictors of VTE. Results:A total of 737 patients were identified, 32 (4.3%) had VTE (DVT = 14; PE = 18). At baseline, VTE patients were less likely to be employed in jobs requiring physical labor (59.4% vs 79.7%, P < .01) and more likely to have osteoporosis (29% vs 15.1%, P = .037) and liver disease (6.5% vs 1.4%, P = .027). Patients with VTE had a larger preoperative sagittal vertical axis (SVA; 93 mm vs 55 mm, P < .01) and underwent larger SVA corrections. VTE was associated with a combined anterior/posterior approach (45% vs 25%, P = .028). VTE patients had a longer hospital stay (10 vs 7 days, P < .05) and higher mortality rate (6.3% vs 0.7%, P < .01). Multivariate analysis demonstrated osteoporosis, lack of physical labor, and increased SVA correction were independent predictors of VTE (r2 = .11, area under the curve = 0.74, P < .05). Conclusions:The incidence of VTE in ASD is 4.3% with a DVT rate of 1.9% and PE rate of 2.4%. Osteoporosis, lack of physical labor, and increased SVA correction were independent predictors of VTE. Patients with VTE had a higher mortality rate compared with non-VTE patients
Performance Verification of the FlashCam Prototype Camera for the Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) is a future gamma-ray observatory that is
planned to significantly improve upon the sensitivity and precision of the
current generation of Cherenkov telescopes. The observatory will consist of
several dozens of telescopes with different sizes and equipped with different
types of cameras. Of these, the FlashCam camera system is the first to
implement a fully digital signal processing chain which allows for a traceable,
configurable trigger scheme and flexible signal reconstruction. As of autumn
2016, a prototype FlashCam camera for the medium-sized telescopes of CTA nears
completion. First results of the ongoing system tests demonstrate that the
signal chain and the readout system surpass CTA requirements. The stability of
the system is shown using long-term temperature cycling.Comment: 5 pages, 13 figures, Proceedings of the 9th International Workshop on
Ring Imaging Cherenkov Detectors (RICH 2016), Lake Bled, Sloveni
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