225 research outputs found

    Use of ERTS data for a multidisciplinary analysis of Michigan resources

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    The author has identified the following significant results. The results of this investigation of ratioing simulated ERTS spectral bands and several non-ERTS bands (all collected by an airborne multispectral scanner) indicate that significant terrain information is available from band-ratio images. Ratio images, which are based on the relative spectral changes which occur from one band to another, are useful for enhancing differences and aiding the image interpreter in identifying and mapping the distribution of such terrain elements as seedling crops, all bare soil, organic soil, mineral soil, forest and woodlots, and marsh areas. In addition, the ratio technique may be useful for computer processing to obtain recognition images of large areas at lower costs than with statistical decision rules. The results of this study of ratio processing of aircraft MSS data will be useful for future processing and evaluation of ERTS-1 data for soil and landform studies. Additionally, the results of ratioing spectral bands other than those currently collected by ERTS-1 suggests that some other bands (particularly a thermal band) would be useful in future satellites

    Use of ERTS data for a multidisciplinary analysis of Michigan resources

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    There are no author-identified significant results in this report

    Application of ERTS-1 data to analysis of agricultural crops and forests in Michigan

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    The results reported are based on analysis of ERTS Frame 1033-15580 collected over southwestern Lower Michigan on August 25, 1972. Major agricultural crops such as corn and soybeans were approaching maturity at this data and forest canopies were dense. Extensive ground truth information was gathered by detailed field study of test strips. This detailed information was supplemented over larger areas by interpretation of RB-57 and C-47 photography and MSS imagery. Recognition processing of ERTS-1 MSS data was carried out on a digital computer. Fields and forest stands were selected as training sets and test areas. Aerial imagery was essential for locating the positions of these selected areas on ERTS digital tapes. The recognition process was successful for each type of vegetation which had a dense green canopy such as forests, corn, and soybeans. Bare soil was also recognizable as a category

    CP Violation in B -> pi+ pi- and the Unitarity Triangle

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    We analyze the extraction of weak phases from CP violation in Bπ+πB\to\pi^+\pi^- decays. We propose to determine the unitarity triangle (ρˉ,ηˉ)(\bar\rho,\bar\eta) by combining the information on mixing induced CP violation in Bπ+πB\to\pi^+\pi^-, SS, with the precision observable sin2β\sin 2\beta obtained from the CP asymmetry in BψKSB\to\psi K_S. It is then possible to write down exact analytical expressions for ρˉ\bar\rho and ηˉ\bar\eta as simple functions of the observables SS and sin2β\sin 2\beta, and of the penguin parameters rr and ϕ\phi. As an application clean lower bounds on ηˉ\bar\eta and 1ρˉ1-\bar\rho can be derived as functions of SS and sin2β\sin 2\beta, essentially without hadronic uncertainty. Computing rr and ϕ\phi within QCD factorization yields precise determinations of ρˉ\bar\rho and ηˉ\bar\eta since the dependence on rr and ϕ\phi is rather weak. It is emphasized that the sensitivity to the phase ϕ\phi enters only at second order and is extremely small for moderate values of this phase, predicted in the heavy-quark limit. Transparent analytical formulas are further given and discussed for the parameter CC of direct CP violation in Bπ+πB\to\pi^+\pi^-. We also discuss alternative ways to analyze SS and CC that can be useful if new physics affects BdB_d--Bˉd\bar B_d mixing. Predictions and uncertainties for rr and ϕ\phi in QCD factorization are examined in detail. It is pointed out that a simultaneous expansion in 1/mb1/m_b and 1/N leads to interesting simplifications. At first order infrared divergences are absent, while the most important effects are retained. Independent experimental tests of the factorization framework are briefly discussed.Comment: 26 pages, 7 figure

    Economic evaluation of crop acreage estimation by multispectral remote sensing

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    The author has identified the following significant results. Photointerpretation of S190A and S190B imagery showed significantly better resolution with the S190B system. A small tendancy to underestimate acreage was observed. This averaged 6 percent and varied with field size. The S190B system had adequate resolution for acreage measurement but the color film did not provide adequate contrast to allow detailed classification of ground cover from imagery of a single date. In total 78 percent of the fields were correctly classified but with 56 percent correct for the major crop, corn

    Predictions for BKγγB \to K \gamma \gamma decays

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    We present a phenomenological study of the rare double radiative decay BKγγB\to K \gamma\gamma in the Standard Model (SM) and beyond. Using the operator product expansion (OPE) technique, we estimate the short-distance (SD) contribution to the decay amplitude in a region of the phase space which is around the point where all decay products have energy mb/3\sim m_b/3 in the rest frame of the BB-meson. At lowest order in 1/Q, where QQ is of order mbm_b, the BKγγB\to K \gamma\gamma matrix element is then expressed in terms of the usual BKB\to K form factors known from semileptonic rare decays. The integrated SD branching ratio in the SM in the OPE region turns out to be ΔB(BKγγ)SMOPE1×109\Delta {\cal{B}}(B \to K \gamma \gamma)_{SM}^{OPE} \simeq 1 \times 10^{-9}. We work out the di-photon invariant mass distribution with and without the resonant background through BK{ηc,χc0}KγγB\to K \{\eta_c,\chi_{c0}\}\to K\gamma \gamma. In the SM, the resonance contribution is dominant in the region of phase space where the OPE is valid. The present experimental upper limit on Bsτ+τB_s \to \tau^+ \tau^- decays, which constrains the scalar/pseudoscalar Four-Fermi operators with τ+τ\tau^+ \tau^-, leaves considerable room for new physics in the one-particle-irreducible contribution to BKγγB\to K \gamma \gamma decays. In this case, we find that the SD BKγγB\to K \gamma \gamma branching ratio can be enhanced by one order of magnitude with respect to its SM value and the SD contribution can lie outside of the resonance peaks.Comment: 17 pages, 4 figures; Note added on Schouten identity and 2 references added; v4: typos in Eqs (8), (44) and erroneous statement on mixing before Eq (44) fixed. All results and conclusions unchange

    Exploring the Unitarity Triangle through CP violation observables in BsK+KB_s \to K^+ K^-

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    We discuss the determination of the CKM parameters from the forthcoming CPCP violation observables in BsK+KB_s \to K^+ K^- decays. Combining the information on mixing induced CP violation in BsK+KB_s \to K^+ K^-, with the BdJ/ψKsB_d \to J/\psi K_s precision observable sin2β\sin 2\beta and the Bs0B^0_s--Bs0ˉ\bar{B^0_s} mixing phase ϕs\phi_s, we propose a determination of the unitarity triangle (ρˉ,ηˉ)(\bar\rho, \bar\eta). Computing the penguin parameters (r,θ)(r, \theta) within QCD factorization yield precise determination of (ρˉ,ηˉ)(\bar\rho, \bar\eta), reflected by a weak dependence on the θ\theta which is shown as a second order effect. The impact of the direct CP violation observable CKKC_{KK} on the penguin parameters are investigated and a lower bound on CKKC_{KK} is extracted. We also discuss the effect of the Bs0B^0_s--Bs0ˉ\bar{B^0_s} new physics mixing phase on the penguin parameters (r,θ)(r, \theta) and SKKS_{KK}. Using the SU(3)-flavour symmetry argument and the current BB-factories data provided by the Bdπ+πB_d \to \pi^+ \pi^- modes, we complement the BsK+KB_s \to K^+ K^- CP-violating observables in a variety of ways, in particular we find that SKK>0S_{KK}>0. Finally we analyze systematically the SU(3)-symmetry breaking factor within QCD factorization.Comment: 22 pages, 6 figures, typos corrected, reference and some remarks adde

    B -> K1 gamma and tests of factorization for two-body non leptonic Bdecays with axial-vector mesons

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    The large branching ratio for B-> K1 gamma recently measured at Belle implies a large B -> K1 transition form factor and large branching ratios for non leptonic B decays involving an axial-vector meson. In this paper we present an analysis of two-body B decays with an axial-vector meson in the final state using naive factorization and the B -> K1 form factors obtained from the measured radiative decays. We find that the predicted B -> J/psi K1 branching ratio is in agreement with experiment. We also suggest that the decay rates of B -> K1 pi, B -> a1 K and B -> b1 K could be used to test the factorization ansatz.Comment: 8 pages; 7 new references included and a comment on K2(1430) in the final state adde

    Forward-backward and isospin asymmetry for B -> K* l+ l- decay in the standard model and in supersymmetry

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    We discuss two dedicated observables in exclusive B -> K* l+ l- decay that can be used to study effects of physics beyond the standard model, namely the forward-backward asymmetry in the lepton spectrum and the isospin-asymmetry between decays of charged and neutral B mesons. We consider the region of large recoil-energy (i.e. small invariant mass of the lepton pair), and employ the QCD factorization approach to exclusive B meson decays. Sub-leading effects in the heavy quark mass expansion have been taken into account for the calculation of the isospin-asymmetry. We give predictions for decay asymmetries in the standard model, and its supersymmetric extension with minimal flavor violation, using parameter values allowed by current experimental constraints on B->X_s gamma decay.Comment: 21 pages, LaTeX with 6 figures, added reference

    Triple combination antibiotic therapy for carbapenemase-producing Klebsiella pneumoniae: a systematic review

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    Abstract Background The spread of carbapenemase-producing K. pneumoniae (CPKP) has become a significant problem worldwide. Combination therapy for CPKP is encouraging, but polymyxin resistance to many antibiotics is hampering effective treatment. Combination therapy with three or more antibiotics is being increasingly reported, therefore we performed a systematic review of triple combination cases in an effort to evaluate their clinical effectiveness for CPKP infections. Methods The PubMed database was searched to identify all published clinical outcomes of CPKP infections treated with triple combination therapy. Articles were stratified into two tiers depending on the level of clinical detail provided. A tier 1 study included: antibiotic regimen, regimen-specific outcome, patient status at onset of infection, and source of infection. Articles not reaching these criteria were considered tier 2. Results Thirty-three studies were eligible, 23 tier 1 and ten tier 2. Among tier 1 studies, 53 cases were included in this analysis. The most common infection was pneumonia (31%) followed by primary or catheter-related bacteremia (21%) and urinary tract infection (17%). Different combinations of antibiotic classes were utilized in triple combinations, the most common being a polymyxin (colistin or polymyxin B, 86.8%), tigecycline (73.6%), aminoglycoside (43.4%), or carbapenem (43.4%). Clinical and microbiological failure occurred in 14/39 patients (35.9%) and 22/42 patients (52.4%), respectively. Overall mortality for patients treated with triple combination therapy was 35.8% (19/53 patients). Conclusions Triple combination therapy is being considered as a treatment option for CPKP. Polymyxin-based therapy is the backbone antibiotic in these regimens, but its effectiveness needs establishing in prospective clinical trials
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