This update aims to provide a critical account of houselessness through the last decade in Brazil—a country of the global south which is currently under a destabilized democracy state—and, more ...specifically, in the gravely unequal city of Fortaleza, located in the northeast of Brazil. Through the analysis of reports, news, official declarations and decrees, alongside the conduction of interviews, an investigation is carried out to understand how the people experiencing houselessness in Fortaleza interact with the state, the third sector and each other. The update reveals, therefore, planning practices that systematically structure the exclusion, the invisibility and the potential criminalization of houseless people by public agencies and the private sector—especially during the COVID-19 health crisis—while it also sheds light on the strength of the social movements and civil organizations that seek effective and emancipatory actions towards overcoming houselesssness.
Radiation from UV-C has been demonstrated as a potential surface decontamination method in addition to several advantages over regular sanitation methods. However, UV-C radiation possibly affects the ...physicochemical properties of meat products. To determine the optimum exposure time for bacterial reduction, 39 chicken breasts, inoculated with a pool of Salmonella spp., were submitted to 3 levels of UV-C intensities (0.62, 1.13, and 1.95 mW/cm2) for up to 120 s. After the optimum exposure time of 90 s was determined, changes in the biogenic amines, total aerobic mesophilic bacteria, Enterobacteriaceae, lipid oxidation, pH, and instrumental color were evaluated in 84 chicken breasts that were irradiated (0.62, 1.13, and 1.95 mW/cm2) and stored at 4°C for 9 d. The groups treated with UV-C radiation exhibited an increase in tyramine, cadaverine, and putrescine contents (P < 0.05). The highest UV-C intensity (1.95 mW/cm2) promoted a decrease in the initial bacterial load, and extended the lag phase and the shelf life. The groups irradiated with 1.13 and 1.95 mW/cm2 exhibited a more stable b* value than the other groups; similar trends for L*, a*, pH, and TBA reactive substance values were observed among all groups. The UV-C light was demonstrated to be an efficient alternative technology to improve the bacteriological quality of chicken meat without negatively affecting the physical and chemical parameters of chicken breast meat. Nonetheless, the increases on the biogenic amines content should be considered as an effect of the UV processing and not as an indicator of bacterial growth.
We present 32 epochs of optical (3300−9700 Å) spectrophotometric observations of the nearby quintessential “normal” type Ia supernova (SN Ia) SN 2011fe in the galaxy M101, extending from −15 to +97 d ...with respect to B-band maximum, obtained by the Nearby Supernova Factory collaboration. SN 2011fe is the closest (μ = 29.04) and brightest (Bmax = 9.94 mag) SN Ia observed since the advent of modern large scale programs for the intensive periodic followup of supernovae. Both synthetic light curve measurements and spectral feature analysis attest to the normality of SN 2011fe. There is very little evidence for reddening in its host galaxy. The homogeneous calibration, intensive time sampling, and high signal-to-noise ratio of the data set make it unique. Thus it is ideal for studying the physics of SN Ia explosions in detail, and for furthering the use of SNe Ia as standardizable candles for cosmology. Several such applications are shown, from the creation of a bolometric light curve and measurement of the 56Ni mass, to the simulation ofdetection thresholds for unburned carbon, direct comparisons with other SNe Ia, and existing spectral templates.
In the last decade, the highest levels of greenhouse gases (GHG) in the atmosphere have been recorded, with carbon dioxide (CO2) being one of the GHGs that most concerns mankind due to the rate at ...which it is generated on the planet. Given its long time of permanence in the atmosphere (between 100 to 150 years); this has deployed research in the scientific field focused on the absorption and desorption of CO2 in the atmosphere. This work presents the study of CO2 adsorption employing materials based on graphene oxide (GO), such as GO foams with different oxidation percentages (3.00%, 5.25%, and 9.00%) in their structure, obtained via an environmentally friendly method. The characterization of CO2 adsorption was carried out in a closed system, within which were placed the GO foams and other CO2 adsorbent materials (zeolite and silica gel). Through a controlled chemical reaction, production of CO2 was conducted to obtain CO2 concentration curves inside the system and calculate from these the efficiency, obtained between 86.28 and 92.20%, yield between 60.10 and 99.50%, and effectiveness of CO2 adsorption of the materials under study. The results obtained suggest that GO foams are a promising material for carbon capture and the future development of a new clean technology, given their highest CO2 adsorption efficiency and yield.
We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory. We use host ...galaxy stellar masses and specific star formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-active galactic nucleus) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low- and high-mass hosts is 0.077 + or - 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 < or =, slant log(Mlow */M sub(middot in circle)) < or =, slant 10.4). Although metallicity has been a favored interpretation for the origin of the Hubble residual trend with host mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor age both evolve along the galaxy mass sequence, thereby presenting equally viable explanations for some or all of the observed SN Ia host bias.
Background and AimsVariation in the composition of floral nectar reflects intrinsic plant characteristics as well as the action of extrinsic factors. Micro-organisms, particularly yeasts, represent ...one extrinsic factor that inhabit the nectar of animal-pollinated flowers worldwide. In this study a ‘microbial imprint hypothesis’ is formulated and tested, in which it is proposed that natural community-wide variation in nectar sugar composition will partly depend on the presence of yeasts in flowers.MethodsOccurrence and density of yeasts were studied microscopically in single-flower nectar samples of 22 animal-pollinated species from coastal xeric and sub-humid tropical habitats of the Yucatán Peninsula, Mexico. Nectar sugar concentration and composition were concurrently determined on the same samples using high-performance liquid chromatography (HPLC) methods.Key ResultsMicroscopical examination of nectar samples revealed the presence of yeasts in nearly all plant species (21 out of 22 species) and in about half of the samples examined (51·8 % of total, all species combined). Plant species and individuals differed significantly in nectar sugar concentration and composition, and also in the incidence of nectar yeasts. After statistically controlling for differences between plant species and individuals, nectar yeasts still accounted for a significant fraction of community-wide variance in all nectar sugar parameters considered. Significant yeast × species interactions on sugar parameters revealed that plant species differed in the nectar sugar correlates of variation in yeast incidence.ConclusionsThe results support the hypothesis that nectar yeasts impose a detectable imprint on community-wide variation in nectar sugar composition and concentration. Since nectar sugar features influence pollinator attraction and plant reproduction, future nectar studies should control for yeast presence and examine the extent to which microbial signatures on nectar characteristics ultimately have some influence on pollination services in plant communities.
Fusarium Head Blight (FHB) is a very important fungal disease that affects small grain cereals worldwide. This disease not only causes yield loses but also crops contamination with mycotoxins such as ...deoxynivalenol (DON) and nivalenol (NIV). Species within the Fusarium graminearum species complex have been described as the main causal agents of this disease, however lately there have been few reports of Fusarium cerealis causing the disease in wheat and barley in different parts of the world. This study evaluated the aggressiveness of F. cerealis to durum wheat cultivars and also mycotoxin production in planta. Moreover, the mycotoxin profile of F. cerealis strains was characterized molecularly and chemically. All durum wheat cultivars showed typical FHB symptoms but the disease severity varied among them in levels up to 66%. In addition, seventeen different compounds were detected in the infected heads including DON, NIV and nivalenol-3-β-d-glucose (NIV3G). NIV was detected in all cultivars and was the most produced mycotoxin with levels ranging from 1.04 to 6.8 mg/kg. On the other hand, the molecular analysis of F. cerealis strains showed that all of them possessed NIV genotype while the chemical assessment showed that the strains were able to produce not only this toxin in vitro but also DON, zearalenone and other twenty-one secondary metabolites. The increasing incidence of F. cerealis and the possible contamination of crops with the mycotoxins that it produces are of great concern for food security and world cereal trade since it has been reported that NIV is more toxic for humans and animals than DON.
•All durum wheat cultivars inoculated with Fusarium cerealis showed FHB symptoms.•Seventeen compounds were detected in the inoculated ears, including deoxynivalenol.•Nivalenol was the most produced mycotoxin in planta.•All strains presented NIV genotype and were able to produce the toxin in vitro.•F. cerealis strains produced several compounds in vitro, including deoxynivalenol.
We propose a novel method to measure flavor oscillations and charge-parity ( C P ) violation in charm mixing. The approach applies to multibody charm decays, such as D0 → K0Sπ+π−, and avoids the need ...for a fit of the decay amplitudes while suppressing biases due to nonuniform signal reconstruction efficiencies as functions of phase space and decay time. Data are partitioned in decay-time and Dalitz-plot regions (bins). The Dalitz-plot bins are symmetric with respect to the principal bisector and chosen to ensure nearly constant values of the strong interaction phases in each. The ratios of signal yields observed in each symmetric bin pair are fit as functions of decay time, using independent auxiliary measurements of the strong interaction phases as constraints, to determine the relevant physics parameters. Simulation shows a 35% improvement in sensitivity to the normalized charm-eigenstate mass difference with respect to existing model-independent methods. In addition, we introduce a parametrization of oscillation and CP-violation effects in charm mixing that has attractive statistical properties and may find wider applicability.
The coastal wetlands of northern Chilean Patagonia are relevant sites for the conservation of migratory waterbirds. The aim of this paper is to compare different marine coastal wetlands to identify ...which factors influence the structure of bird assemblages. Sediment samples were collected, and the birds were surveyed in four wetlands: Chullec, Curaco de Vélez and Quinchao on Quinchao Island, and Putemún on Chiloé Island in 4 seasonal sampling campaigns. The composition of the sediment did not change during the year, with a predominance of sandy sediments except in Putemún where gravel dominates. The size of the sediment particle decreased from the upper (0 to 30 m) to the lower (100 m) intertidal. The abundances of benthic organisms varied between intertidal levels in all wetlands and seasonally in Chullec and Curaco de Vélez, being lower during warm seasons. Thirty-four species of birds were recorded with Anatidae, Laridae and Scolopacidae showing the highest species richness. A principal component analysis clustered the wetlands of Quinchao Island and the variables that account for 35.8% of the variance are sandy sediments, the presence of Scolopacidae, Laridae, Furnariidae and Haematopodidae among birds and Polychaeta, Malacostraca and Enopla in the benthos. In the wetlands of Quinchao Island there was a relationship between the composition of the sediment, distribution, and type of benthic communities with the presence of some bird taxa. The bird assemblages change seasonally and were similar to each other during warm seasons, probably due to the availability of food for migratory birds and sediment characteristics.
We present a new atmospheric extinction curve for Mauna Kea spanning 3200–9700 Å. It is the most comprehensive to date, being based on some 4285 standard star spectra obtained on 478 nights spread ...over a period of 7 years obtained by the Nearby SuperNova Factory using the SuperNova Integral Field Spectrograph. This mean curve and its dispersion can be used as an aid in calibrating spectroscopic or imaging data from Mauna Kea, and in estimating the calibration uncertainty associated with the use of a mean extinction curve. Our method for decomposing the extinction curve into physical components, and the ability to determine the chromatic portion of the extinction even on cloudy nights, is described and verified over the wide range of conditions sampled by our large dataset. We demonstrate good agreement with atmospheric science data obtain at nearby Mauna Loa Observatory, and with previously published measurements of the extinction above Mauna Kea.
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