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We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}â²10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}â²(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{Ï}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}â²0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.
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The 80% mortality rate of pancreatic-cancer (PC) makes early diagnosis a challenge. Oral fluids (OF) may be considered the ultimate body fluid for non-invasive examinations. We have developed techniques to improve visualization of minor OF proteins thereby overcoming major barriers to using OF as a diagnostic fluid. The aim of this study was to establish a short discriminative panel of OF biomarkers for the detection of PC. Unstimulated OF were collected from PC patients and controls (n = 30). High-abundance-proteins were depleted and the remaining proteins were analyzed by two-dimensional-gel-electrophoresis and quantitative dimethylation-liquid-chromatography-tandem mass-spectrometry. Label-free quantitative-mass-spectrometry analysis (qMS) was performed on 20 individual samples (n = 20). More than 100 biomarker candidates were identified in OF samples, and 21 had a highly differential expression profile. qMS analysis yielded a ROC-plot AUC value of 0.91 with 90.0% sensitivity and specificity for a combination of five biomarker candidates. We found a combination of five biomarkers for PC. Most of these proteins are known to be related to PC or other gastric cancers, but have never been detected in OF. This study demonstrates the importance of novel OF depletion methodologies for increased protein visibility and highlights the clinical applicability of OF as a diagnostic fluid.
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Biomarcadores Tumorais/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismo , Proteômica , Saliva/metabolismo , Idoso , Estudos de Casos e Controles , Eletroforese em Gel Bidimensional , Humanos , Metilação , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismoRESUMO
We propose and demonstrate, numerically and experimentally, use of sparsity as prior information for extending the capabilities and performance of techniques and devices for laser pulse diagnostics. We apply the concept of sparsity in three different applications. First, we improve a photodiode-oscilloscope system's resolution for measuring the intensity structure of laser pulses. Second, we demonstrate the intensity profile reconstruction of ultrashort laser pulses from intensity autocorrelation measurements. Finally, we use a sparse representation of pulses (amplitudes and phases) to retrieve measured pulses from incomplete spectrograms of cross-correlation frequency-resolved optical gating traces.
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Baryon acoustic oscillations in the early Universe are predicted to leave an as yet undetected signature on the relative clustering of total mass versus luminous matter. A detection of this effect would provide an important confirmation of the standard cosmological paradigm and constrain alternatives to dark matter as well as nonstandard fluctuations such as compensated isocurvature perturbations (CIPs). We conduct the first observational search for this effect, by comparing the number-weighted and luminosity-weighted correlation functions, using the SDSS-III BOSS Data Release 10 CMASS sample. When including CIPs in our model, we formally obtain evidence at 3.2σ of the relative clustering signature and a limit that matches the existing upper limits on the amplitude of CIPs. However, various tests suggest that these results are not yet robust, perhaps due to systematic biases in the data. The method developed in this Letter used with more accurate future data such as that from DESI, is likely to confirm or disprove our preliminary evidence.
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We present a mass map reconstructed from weak gravitational lensing shear measurements over 139 deg2 from the Dark Energy Survey science verification data. The mass map probes both luminous and dark matter, thus providing a tool for studying cosmology. We find good agreement between the mass map and the distribution of massive galaxy clusters identified using a red-sequence cluster finder. Potential candidates for superclusters and voids are identified using these maps. We measure the cross-correlation between the mass map and a magnitude-limited foreground galaxy sample and find a detection at the 6.8σ level with 20 arc min smoothing. These measurements are consistent with simulated galaxy catalogs based on N-body simulations from a cold dark matter model with a cosmological constant. This suggests low systematics uncertainties in the map. We summarize our key findings in this Letter; the detailed methodology and tests for systematics are presented in a companion paper.
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For most people who are blind, exploring an unknown environment can be unpleasant, uncomfortable, and unsafe. Over the past years, the use of virtual reality as a learning and rehabilitation tool for people with disabilities has been on the rise. This research is based on the hypothesis that the supply of appropriate perceptual and conceptual information through compensatory sensorial channels may assist people who are blind with anticipatory exploration. In this research we developed and tested the BlindAid system, which allows the user to explore a virtual environment. The two main goals of the research were: (a) evaluation of different modalities (haptic and audio) and navigation tools, and (b) evaluation of spatial cognitive mapping employed by people who are blind. Our research included four participants who are totally blind. The preliminary findings confirm that the system enabled participants to develop comprehensive cognitive maps by exploring the virtual environment.
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Public support is crucial for successful implementation of wastewater reuse projects. This paper analyses the findings of a questionnaire-type survey (256 participants) conducted to determine the attitude of Israeli urban public towards possible urban reuse options. The paper summarises the support/objection to 13 reuse options and the correlation between support and environmental awareness and perceptions. Results show that a high proportion of the participants supported options perceived as low-contact, such as irrigation of public parks (96%), sidewalk landscaping (95%) and use in the construction industry (94%), while higher-contact reuse options found less support (e.g. commercial launderettes, 60%). No correlation was found between biographical characteristics and support (education, gender, income, age). Based on the results, public campaigns in Israel should focus on disseminating information regarding wastewater treatment technologies, discuss health related issues, highlight the positive economic impact of water reuse and generate a positive public opinion, as these factors tend to influence individuals to support reuse projects.
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Cidades , Conservação dos Recursos Naturais , Opinião Pública , Eliminação de Resíduos Líquidos , Abastecimento de Água , Coleta de Dados , IsraelRESUMO
Advances in the seeded ambient temperature ferrite process for treatment of acid mine drainage (AMD) are described. Magnetite formation requires that the oxidation rate of ferrous to ferric does not exceed the rate at which ferrous iron is incorporated into the crystal structure (dehydroxylation-crystallization). If the oxidation rate is too high, then ferric-only oxides form, an effect exacerbated by the presence of calcium. NaOH was used to raise the pH of simulated AMD, which also contained calcium so as to simulate the use of lime (i.e., the dissolved Ca/ Fe2+ concentration was maintained at 1:1 bythe coaddition of CaCl2 because this is the Ca/Fe ratio that occurs when pH is elevated by the dissolution of lime). Raising the pH to 10.5 causes Fe2+ to precipitate as "ferrous intermediate" (FI), which is then partially oxidized to magnetite (Fe2+Fe3+2O4). The inhibitory effect of calcium is overcome by a combination of magnetite seed particles, high FI concentrations, and aging. High FI concentrations are easily obtained, even from AMD low in Fe2+, by a contact stabilization reactor-settler sequence. Results for simultaneous removal of cobalt, a metal found in significant concentrations in South African AMD, are also presented.
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Cobalto/análise , Compostos Férricos/química , Mineração , Poluentes Químicos da Água/análise , Poluição da Água/prevenção & controle , Purificação da Água/métodos , Cálcio/química , Óxido Ferroso-Férrico/química , Concentração de Íons de Hidrogênio , Metais Pesados/análise , Oxirredução , África do Sul , Fatores de Tempo , Difração de Raios XRESUMO
The aim of this research was to investigate the feasibility of treating liquid dairy wastes by a vertical bed equipped with an innovative passive aeration system. The vertical bed (32 liter) was operated by recirculating consecutive batches of liquid waste in the column. Batches of liquid waste were applied at two different rates: 1) each batch was recirculated for 72 hours, and 2) each batch was recirculated for 24 hours. Settled liquid dairy wastes (5000 mg l(-1) COD, 2000 mg l(-1) BOD and 2500 mg l(-1) TSS) were used in the experiments. When the reactor operated with each batch recirculating for 72 hours, the BOD and COD reduction were 66% and 40%, respectively. The vertical bed operated successfully without the need for an additional rest period. The main removal was observed to take place during the first 20 hours. No biomass or solids accumulation was observed indicating that the remaining 52 hours of recirculation were actually used for bed regeneration, i.e. integrated rest period. When the reactor operated with each batch recirculating for 24 hours, the system clogged after 21 days. An additional 24 day rest period was needed in order to free 94% of the initial void space. In this mode, the BOD and COD reduction were 67% and 47%, respectively. The overall COD removal in a complete operational cycle (feeding period followed by a rest period) was 467 g COD m(-3) d(-1) (996 g COD m(-2) d(-1)). This value is 1.4 higher than the COD removal obtained in the 72 hour per batch mode and shows the advantage of conventional vertical bed operation of intensive feeding followed by rest period rather than a rest period integrated into the feeding cycle.
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Indústria de Laticínios , Eliminação de Resíduos Líquidos/métodos , Movimentos do Ar , Animais , Bovinos , Desenho de Equipamento , Movimentos da ÁguaRESUMO
The production of gaseous nitrogen compounds, particularly the greenhouse gas nitrous oxide, was investigated in a novel process for ammonium removal from wastewater. The process is based on the adsorption of ammonium on zeolite followed by bioregeneration. The zeolite serves the dual purpose of an ion exchanger and a physical carrier for nitrifying bacteria which bio-regenerate the ammonium saturated mineral. An analysis of the nitrifying population composition in the reactor fed with simulated secondary effluent (NH4+ = 50 mg/l) revealed that about half of the bacteria in the biofilm were common ammonium oxidizers Nitrosococcus mobilis and Nitrosomonas, while the other half were nitrite oxidizers. The amount of nitrogen losses, under different conditions, and the identification of the emitted gases (N2 or N2O) were investigated in two sets of experiments: (I) batch experiments using biomass originating from the ion exchange reactor with and without the addition of nitrite, and (II) continuous experiments using the ion exchange reactor with zeolite as the biomass carrier. In the batch experiments, nitrite and oxygen concentrations were determined as the major parameters responsible for the formation of gaseous nitrogen gas during ammonia oxidation by autotrophic bacteria. Continuous experiments showed that the major parameter significantly affecting nitrogen losses was the amount of ammonium adsorbed by the zeolite during the ion exchange phase. The amount of ammonium adsorbed determines the ammonium concentration during the initial period of bioregeneration, which in turn directly influences oxygen demand and the resulting concentrations of oxygen and nitrite. It was concluded that the formation of nitrogen gas compounds in the ion exchange/bioregeneration process can be eliminated by adjusting the operational regime to have a shorter adsorption phase resulting in smaller amounts of ammonium adsorbed per cycle.
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Reatores Biológicos , Bradyrhizobiaceae/fisiologia , Compostos de Nitrogênio/análise , Óxido Nitroso/análise , Compostos de Amônio Quaternário/metabolismo , Adsorção , Biodegradação Ambiental , Biomassa , Compostos de Nitrogênio/química , Óxido Nitroso/química , Oxirredução , Compostos de Amônio Quaternário/química , Volatilização , Eliminação de Resíduos Líquidos , Zeolitas/químicaRESUMO
We constrain f(nu) identical with Omega(nu)/Omega(m), the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find f(nu)<0.13 (at 95% confidence) for a prior of 0.1
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The large-scale structure in the distribution of galaxies is thought to arise from the gravitational instability of small fluctuations in the initial density field of the Universe. A key test of this hypothesis is that forming superclusters of galaxies should generate a systematic infall of other galaxies. This would be evident in the pattern of recessional velocities, causing an anisotropy in the inferred spatial clustering of galaxies. Here we report a precise measurement of this clustering, using the redshifts of more than 141,000 galaxies from the two-degree-field (2dF) galaxy redshift survey. We determine the parameter beta = Omega0.6/b = 0.43 +/- 0.07, where Omega is the total mass-density parameter of the Universe and b is a measure of the 'bias' of the luminous galaxies in the survey. (Bias is the difference between the clustering of visible galaxies and of the total mass, most of which is dark.) Combined with the anisotropy of the cosmic microwave background, our results favour a low-density Universe with Omega approximately 0.3.
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A fluidized bed reactor for nitrification with chalk as the biomass carrier and the sole buffer agent was studied. Chalk dissolution in the reactor was found to follow the stoichiometric ratio of 1 mole of CaCO3 dissolved for each mole of NH4+ oxidized. Three batches of chalk, each one having a different dissolution rate, were used to replace the dissolved chalk. The three dissolution rates resulted in three different steady state pH levels in the reactor (4.7-6.6) and nitrification rates. Nitrification was found to be limited by either the chalk dissolution rate or dissolved oxygen concentration depending on the type of chalk used. A maximal nitrification rate of 1.44 g NH4(+)-N/l reactor.d was observed. The average cell yield was 0.1 g cells/g N oxidized, similar to the cell yield during reactor start-up when the pH was 7. The specific ammonium oxidation rates varied between 0.08 and 0.15 mg NH4(+)-N oxidized/mg protein.h, values which are in the reported range for nitrification at pH 7 to 8. Oxygen update rate (OUR) results indicated that the major mechanism responsible for the high nitrification rate observed in the reactor operating at low pH seems to be the favorable microenvironment provided by the chalk.
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Bactérias , Biofilmes , Reatores Biológicos , Carbonato de Cálcio , Nitritos , Compostos de Amônio Quaternário , Bactérias/metabolismo , Soluções Tampão , Concentração de Íons de Hidrogênio , Cinética , Oxigênio/análise , Consumo de Oxigênio , Água/análise , Purificação da Água/métodosRESUMO
A novel vertical bed process for the removal of ammonium from secondary effluents, using a "passive air pump", has been developed. The process is based on convective aeration caused by a fill and draw operational sequence, and combines the advantages of the vertical wetlands concept with the high loading rates typically associated with trickling filters. Experiments were carried out in a 500-l reactor using simulative effluents and actual municipal secondary effluents. A maximal ammonium removal rate of 1100 g N/m2 reactor/d was achieved using simulative effluents and an effective gravel size of 0.96 mm. At all hydraulic loads applied, the nitrification rate was found to be limited by the oxygen transfer rate. The small-size medium used with simulative effluents clogged when using actual municipal secondary effluents. Two other media (2.46 mm and 4.31 mm) did not clog during the entire experimental period and a maximum removal load of 300 g N/m2 reactor/d was achieved. This value is still much higher than typical rates reported for conventional vertical beds.
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Filtração/métodos , Compostos de Amônio Quaternário/química , Purificação da Água/métodos , Filtração/instrumentação , Concentração de Íons de Hidrogênio , Nitratos/análise , Nitritos/análise , Oxigênio/análise , Oxigênio/química , Compostos de Amônio Quaternário/análise , Esgotos/químicaRESUMO
The quantitative morphological classification of galaxies is important for understanding the origin of type frequency and correlations with environment. However, galaxy morphological classification is still mainly done visually by dedicated individuals, in the spirit of Hubble's original scheme and its modifications. The rapid increase in data on galaxy images at low and high redshift calls for a re-examination of the classification schemes and for automatic methods. Here are shown results from a systematic comparison of the dispersion among human experts classifying a uniformly selected sample of more than 800 digitized galaxy images. These galaxy images were then classified by six of the authors independently. The human classifications are compared with each other and with an automatic classification by an artificial neural network, which replicates the classification by a human expert to the same degree of agreement as that between two human experts.