119 research outputs found

    A List of Marine Algae from Seashores of Iran (Hormozgan Province)

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    Seashores of Hromzgan province in south of Iran were studied for collection and recogna-tion of algal flora (1991-1996). 150 species of marine algae were recognized, including 36 Chlorophyta (16 new). 33 Phaeophyta (15 new). 75 Rhodophyta (42 new), 3 Xanthophyta (2 new) and 3 Cyanophyta (2 new). In this study number of algal species from Iranian seashores are increased to 201 species

    Single-Setting Bilateral Hand-Assisted Laparoscopic Partial Nephrectomy

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    Abstract Purpose: To assess the feasibility and safety of single-setting bilateral hand-assisted laparoscopic partial nephrectomy. Materials and Methods: Between August 2003 and June 2004, we performed single-setting bilateral laparoscopic partial nephrectomies on three patients. A hand-assisted approach was used, employing the same hand-assistance incision for both sides. Renal hilar clamping was not required, as the depth of penetration of all six tumors was only 0 to 4mm (mean, 1.8mm). The tumor diameters ranged from 1.8 to 3.8cm (mean, 2.4cm). Results: All operations were performed successfully, with no conversion to open surgery. Excision was performed with bipolar forceps, and final hemostasis was obtained with an argon beam coagulator (Valleylab, Boulder, CO) and Floseal (Baxter, Deerfield, IL), without suturing. The mean estimated blood loss was 208mL. The mean operative time was 246 minutes, which included repositioning. There were no intraoperative complications, and the postoperative course was uneventful in all patients except for a hospital stay of 5 days in one patient owing to transient ileus. Pathology revealed a benign lesion on one side and renal cell carcinoma on the other side in two patients, and bilateral leiomyomas in one patient. All margins of resection were negative, and neither of the two patients with cancer has had recurrence at a mean follow-up of 51 months. Among all three patients, the mean preoperative serum creatinine was 0.9mg/dL, and the average level at a mean of 35 months postoperatively was 1.0mg/dL. Conclusion: Single-setting bilateral hand-assisted laparoscopic partial nephrectomies can be safely and effectively performed on patients with bilateral small exophytic kidney tumors. We do not recommend this technique if both kidneys require temporary hilar occlusion, but it can be considered if only one kidney requires hilar occlusion.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78122/1/end.2008.0549.pd

    Estimate of the Cosmological Bispectrum from the MAXIMA-1 Cosmic Microwave Background Map

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    We use the measurement of the cosmic microwave background taken during the MAXIMA-1 flight to estimate the bispectrum of cosmological perturbations. We propose an estimator for the bispectrum that is appropriate in the flat sky approximation, apply it to the MAXIMA-1 data and evaluate errors using bootstrap methods. We compare the estimated value with what would be expected if the sky signal were Gaussian and find that it is indeed consistent, with a χ2\chi^2 per degree of freedom of approximately unity. This measurement places constraints on models of inflation.Comment: 5 pages, 2 figures. New version to match paper accepted for publication in Phys. Rev. Lett. Non-diagonal terms included leading to new limits on f_N

    Determining Foreground Contamination in CMB Observations: Diffuse Galactic Emission in the MAXIMA-I Field

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    Observations of the CMB can be contaminated by diffuse foreground emission from sources such as Galactic dust and synchrotron radiation. In these cases, the morphology of the contaminating source is known from observations at different frequencies, but not its amplitude at the frequency of interest for the CMB. We develop a technique for accounting for the effects of such emission in this case, and for simultaneously estimating the foreground amplitude in the CMB observations. We apply the technique to CMB data from the MAXIMA-1 experiment, using maps of Galactic dust emission from combinations of IRAS and DIRBE observations, as well as compilations of Galactic synchrotron emission observations. The spectrum of the dust emission over the 150--450 GHz observed by MAXIMA is consistent with preferred models but the effect on CMB power spectrum observations is negligible.Comment: 19 pages, 8 figures, accepted for publication in the Astrophysical Journal. Monor changes to match the published versio

    MAXIPOL: Cosmic Microwave Background Polarimetry Using a Rotating Half-Wave Plate

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    We discuss MAXIPOL, a bolometric balloon-borne experiment designed to measure the E-mode polarization of the cosmic microwave background radiation (CMB). MAXIPOL is the first bolometric CMB experiment to observe the sky using rapid polarization modulation. To build MAXIPOL, the CMB temperature anisotropy experiment MAXIMA was retrofitted with a rotating half-wave plate and a stationary analyzer. We describe the instrument, the observations, the calibration and the reduction of data collected with twelve polarimeters operating at 140 GHz and with a FWHM beam size of 10 arcmin. We present maps of the Q and U Stokes parameters of an 8 deg^2 region of the sky near the star Beta Ursae Minoris. The power spectra computed from these maps give weak evidence for an EE signal. The maximum-likelihood amplitude of l(l+1)C^{EE}_{l}/(2 pi) is 55_{-45}^{+51} uK^2 (68%), and the likelihood function is asymmetric and skewed positive such that with a uniform prior the probability that the amplitude is positive is 96%. This result is consistent with the expected concordance LCDM amplitude of 14 uK^2. The maximum likelihood amplitudes for l(l+1)C^{BB}_{l}/(2 pi) and â„“(â„“+1)Câ„“EB/2Ď€\ell(\ell+1)C^{EB}_{\ell}/2\pi are -31_{-19}^{+31} and 18_{-34}^{+27} uK^2 (68%), respectively, which are consistent with zero. All of the results are for one bin in the range 151 < l < 693. Tests revealed no residual systematic errors in the time or map domain. A comprehensive discussion of the analysis of the data is presented in a companion paper.Comment: 19 pages, 11 figures, 2 tables, submitted to Ap

    Multimode VIS–NIR transmission through silver coated hollow optical waveguides

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    Multimode transmission of continuous wave 633 nm radiation and 1064 nm Q-switched Nd:YAG pulses using silver coated hollow core optical waveguides (HCWs) with bore diameters of 700 μm and 1000 μm is reported. The effect of launch conditions, input beam polarization and waveguide bore diameter on the pulse energy transmission and potential for focussing the beam effectively at the HCW exit is detailed. An optimal launch f-number range of 155–165 is identified for minimizing the exit angle

    MAXIMA: an experiment to measure temperature anisotropy in the cosmic microwave background

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    We describe the MAXIMA experiment, a balloon-borne measurement designed to map temperature anisotropy in the Cosmic Microwave Background (CMB) over a wide range of angular scales (multipole range 80 < l < 800). The experiment consists of a 1.3 m diameter off-axis Gregorian telescope and a receiver with a 16 element array of bolometers cooled to 100 mK. The frequency bands are centered at 150, 240, and 410 GHz. The 10' FWHM beam sizes are well matched to the scale of acoustic peaks expected in the angular power spectrum of the CMB. The first flight of the experiment in its full configuration was launched in August 1998. A 122 sq-deg map of the sky was made near the Draco constellation during the 7 hour flight in a region of extremely low galactic dust contamination. This map covers 0.3% of the sky and has 3200 independent beamsize pixels. We describe the MAXIMA instrument and its performance during the recent flight.Comment: To appear in proceedings of `3K Cosmology', ed. F Melchiorri, Conference held Oct 5-10 1998, Rome, 13 pages LaTeX (using aipproc2.sty & aipproc2.cls), Postscript with higher resolution graphics available at http://cfpa.berkeley.edu/group/cmb/gen.htm

    From the time-ordered data to the Maximum-Likelihood temperature maps of the Cosmic Microwave Backgorund anisotropy

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    We review selected methods of the Cosmic Microwave Background data analysis appropriate for the analysis of the largest currently available data sets. We focus on techniques of the time-ordered data manipulation and map making algorithms based on the maximum-likelihood approach. The presented methods have been applied to the MAXIMA data analysis (Hanany et al 2000) and the description of the algorithms is illustrated with the examples drawn from that experience. The more extensive presentation of the here-mentioned issues will be given in the forthcoming paper (Stompor et al 2001)

    The Quintessential CMB, Past & Future

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    The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information and high redshift supernova (SN1) observations to explore the inflation-based cosmic structure formation paradigm. Here we primarily focus on a simplified inflation parameter set, {omega_b,omega_{cdm},Omega_{tot}, Omega_Q,w_Q, n_s,tau_C, sigma_8}. After marginalizing over the other cosmic and experimental variables, we find the current CMB+LSS+SN1 data gives Omega_{tot}=1.04\pm 0.05, consistent with (non-baroque) inflation theory. Restricting to Omega_{tot}=1, we find a nearly scale invariant spectrum, n_s =1.03 \pm 0.07. The CDM density, omega_{cdm}=0.17\pm 0.02, is in the expected range, but the baryon density, omega_b=0.030\pm 0.004, is slightly larger than the current nucleosynthesis estimate. Substantial dark energy is inferred, Omega_Q\approx 0.68\pm 0.05, and CMB+LSS Omega_Q values are compatible with the independent SN1 estimates. The dark energy equation of state, parameterized by a quintessence-field pressure-to-density ratio w_Q, is not well determined by CMB+LSS (w_Q<-0.3 at 95%CL), but when combined with SN1 the resulting w_Q<-0.7 limit is quite consistent with the w_Q=-1 cosmological constant case. Though forecasts of statistical errors on parameters for current and future experiments are rosy, rooting out systematic errors will define the true progress.Comment: 14 pages, 3 figs., in Proc. CAPP-2000 (AIP), CITA-2000-6

    The MAXIMA Experiment: Latest Results and Consistency Tests

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    The MAXIMA cosmic microwave background anisotropy experiment had a significant impact on cosmology. Results from the program have played a significant role in determining the geometry of the universe, given strong supporting evidence to inflation, and, in combination with other astrophysical data, showed that the universe is filled with dark matter and energy. We present a subset of the internal consistency checks that were carried out on the MAXIMA-1 data prior to their release, which demonstrate that systematics errors were much smaller than statistical errors. We also discuss the MAXIMA-2 flight and data, compare the maps of MAXIMA-1 and -2 in areas where they overlap and show that the two independent experiments confirm each other. All of these results demonstrate that MAXIMA mapped the cosmic microwave background anisotropy with high accuracyComment: to be published in C.R. Physique, 2003, (Academie des Science), 14 pages, figures embedded, a version with high quality figures is available from http://cosmology.berkeley.edu/maxima/comp_publications.htm
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