The Gran Chaco is a wide ecologic-geographic region comprising northern Argentina, western Paraguay, southern Bolivia and the southwestern extreme of Brazil. This region exhibits extreme ...temperatures, annually regular frosts, and sedimentary soils; it has been dramatically threatened by agriculture expansion in recent decades. Therefore, increasing knowledge of plant diversity is critical for conservation purposes. We present a Legume checklist of the Gran Chaco ecoregion including conservation status of its endemic species. Leguminosae is the third most diverse plant family in the Neotropics. Assuming a rigorous spatial definition of the Gran Chaco, we recorded 98 genera, 362 species, and 404 specific and infraspecific taxa. Endemic/typical taxa were 17%, comparable to adjacent tropical plant formations, and they were found in higher percentages in Caesalpinioideae (24%) and Cercidoideae (33%) than Papilionoideae (11%) subfamily. We also analyzed the plant diversity comparing lineages and subregions. The Gran Chaco Legumes are predominantly widespread generalists, or they belong to either Chaco sensu stricto or Neotropical Seasonally Dry Tropical Forest (SDTF) lineages. Though the Humid Chaco registered the highest species richness, Dry Chaco and Sierra Chaco, the most threatrened subregions, exhibited the highest percentages of exclusive and proper Chaco-lineage species. These results suggest that diversification of Legumes has been most relevant in Dry Chaco and Sierra Chaco, probably by their more demanding and harsh environmental conditions limiting the dispersion of generalists or intrusive-invading species. This study is paramount to reach an improved delimitation of the Gran Chaco ecoregion in transitional areas with the SDTF and Cerrado formations. Conservation status is critical in genera of high economic interest, such as Arachis, Mimosa and Prosopis. At least one third of endemic taxa exhibit a critical status of conservation or are endangered, many of them being relevant to inbreeding program or exhibiting multiple economic uses.
Abstract
We study the relation between obscuration and supermassive black hole (SMBH) accretion using a large sample of hard X-ray selected active galactic nuclei (AGNs). We find a strong decrease in ...the fraction of obscured sources above the Eddington limit for dusty gas (
log
λ
Edd
≳
−
2
) confirming earlier results, and consistent with the radiation-regulated unification model. This also explains the difference in the Eddington ratio distribution functions (ERDFs) of type 1 and type 2 AGNs obtained by a recent study. The break in the ERDF of nearby AGNs is at
log
λ
Edd
*
=
−
1.34
±
0.07
. This corresponds to the
λ
Edd
where AGNs transition from having most of their sky covered by obscuring material to being mostly devoid of absorbing material. A similar trend is observed for the luminosity function, which implies that most of the SMBH growth in the local universe happens when the AGN is covered by a large reservoir of gas and dust. These results could be explained with a radiation-regulated growth model, in which AGNs move in the
N
H
–
λ
Edd
plane during their life cycle. The growth episode starts with the AGN mostly unobscured and accreting at low
λ
Edd
. As the SMBH is further fueled,
λ
Edd
,
N
H
and the covering factor increase, leading the AGN to be preferentially observed as obscured. Once
λ
Edd
reaches the Eddington limit for dusty gas, the covering factor and
N
H
rapidly decrease, leading the AGN to be typically observed as unobscured. As the remaining fuel is depleted, the SMBH goes back into a quiescent phase.
We present integral field spectroscopic observations of NGC 5972 obtained with the Multi-Unit Spectroscopic Explorer at the Very Large Telescope. NGC 5972 is a nearby galaxy containing both an active ...galactic nucleus (AGN) and an extended emission-line region (EELR) reaching out to ∼17 kpc from the nucleus. We analyze the physical conditions of the EELR using spatially resolved spectra, focusing on the radial dependence of ionization state together with the light-travel time distance to probe the variability of the AGN on ≳104 yr timescales. The kinematic analysis suggests multiple components: (a) a faint component following the rotation of the large-scale disk, (b) a component associated with the EELR suggestive of extraplanar gas connected to tidal tails, and (c) a kinematically decoupled nuclear disk. Both the kinematics and the observed tidal tails suggest a major past interaction event. Emission-line diagnostics along the EELR arms typically evidence Seyfert-like emission, implying that the EELR was primarily ionized by the AGN. We generate a set of photoionization models and fit these to different regions along the EELR. This allows us to estimate the bolometric luminosity required at different radii to excite the gas to the observed state. Our results suggest that NGC 5972 is a fading quasar, showing a steady gradual decrease in intrinsic AGN luminosity, and hence the accretion rate onto the SMBH, by a factor ∼100 over the past 5 × 104 yr.
During a Brazilian multicentric antimicrobial resistance surveillance study, colistin resistance was investigated in 4,620 Enterobacteriaceae isolated from human, animal, food and environmental ...samples collected from 2000 to 2016. We present evidence that mcr-1-positive Escherichia coli has been emerging in South America since at least 2012, supporting a previous report on the possible acquisition of mcr-1-harbouring E. coli by European travellers visiting Latin American countries.
Concerns about ammonia (NH3) losses from nitrogen (N) mineral fertilizers have forced policymakers to set emission reduction commitments across Europe. Although best available techniques (BATs) have ...been recommended, large uncertainties still exist due to poorly targeted site-specific approaches that might compromise their effectiveness. Here we proposed and tested a conceptual framework designed to identify most effective BATs that reduce NH3 at the site-specific level. The study was conducted in the Veneto region, northeast Italy. After the mapping of NH3 emission potential areas, BATs and business-as-usual N fertilization scenarios were assessed using a modified version of the DNDC agroecosystem model and compared with urea broadcast distribution under different pedo-climatic conditions. The most promising practices were further tested in a field experiment using a wind tunnel combined with a FTIR gas analyzer. Results showed that closed-slot injection reduced NH3 emissions with any type of mineral or organic fertilizers. Injected application, with ammonium nitrate or organic fertilizers, reduced NH3 loss in maize by 75% and 96%, respectively, and in winter wheat by 87% and 98%, compared to surface broadcast. Injection was the most promising technology to support, being already available to farmers. However, some increase in nitrate leaching was observed, mostly in case of winter wheat (+24% for AN injection; +89% for organic fertilizers). By contrast, urea incorporation with hoeing, the most common technique used by farmers in spring crops, did not show satisfactory results, because the partial burial of urea caused strong NH3 emissions that were even higher compared to surface broadcast. Recommended NH3 reduction techniques should be tailored to local pedo-climatic and management conditions, and evaluated, in a holistic approach, considering all N fluxes in the environment.
•A site-specific approach is required to quantify NH3 emissions from N fertilizer management.•Urea incorporation with hoeing suffers from partial burial that does not limit NH3 emissions.•NH3 emission reduction is achieved by closed-slot injection of mineral N fertilizer.•Technologies limiting NH3 emission can result in increased N leaching or N2O emissions.
The interaction between wakes and rotors is typically detrimental in terms of the overall power production of a wind farm. The recently studied wind farm controllers represent a promising way to ...increase the energy harvested through the mitigation of the effects induced by wake impingement. Recently, a novel methodology, based on a dynamic variation of induction, has been proposed as an alternative to steady induction and wake redirection controls. According to this new technology, a periodic collective motion of blade pitch generates a dynamic induction, associated with a stronger flow mixing and therefore a faster wake recovery. Although this technique proved to be effective in terms of power increase, both in numerical simulations and in wind tunnel experiments, much is to be done in order to demonstrate its feasibility. In particular, the impact of dynamic induction control in terms of downstream turbine dynamics has not been yet analyzed in detail. This paper presents a CFD-based analysis aimed at describing the response of a downstream rotor inside the wake of an upstream machine performing dynamic induction control. Specifically, the periodic induction entails a pulsating flow downstream which interacts significantly with the aero-servo-elastic dynamics of the downstream turbines. For low wind speeds, such an oscillating flow may trigger a shut-down/start-up sequence any time the velocity results lower than the cut-in speed.
Few studies have reported the effect of 10-valent pneumococcal conjugate vaccine (PCV10) on otitis media (OM) in infants. In particular, no population-based study in upper-middle income countries is ...available. In 2010, Brazil introduced PCV10 into its routine National Immunization Program using a 3+1 schedule. We measured the impact of PCV10 on all-cause OM in children. An interrupted time-series analysis was conducted in Goiânia/Brazil considering monthly rates (per 100,000) of all-cause OM outpatient visits in children aged 2-23 months. We used case-based data from the Outpatient Visits Information System of the Unified Health System coded for ICD-10 diagnosis for the period of August/2008 to July/2015. As a comparator, we used rates of outpatient visits due to all-other causes. The relative reduction of all-cause OM and all-other causes of outpatient visits were calculated as the difference between the predicted and observed cumulative rates of the PCV10 post-vaccination period. We then subtracted the relative reduction of all-other causes of outpatient visits from all-cause OM to obtain the impact of PCV10 on OM. In total, 6,401 OM outpatient visits were recorded in 4,793 children aged 2-23 months. Of these, 922 (19.2%) children had more than one OM episode. A significant reduction in all-cause OM visits was observed (50.7%; 95%CI: 42.2-59.2%; p = 0.013), while the reduction in visits due to all-other causes was 7.7% (95% CI 0.8-14.7%; p<0.001). The impact of PCV10 on all-cause OM was thus estimated at 43.0% (95%CI 41.4-44.5). This is the first study to show significant PCV10 impact on OM outpatient visits in infants in a developing country. Our findings corroborate the available evidence from developed countries.
•Conservation agriculture management system affected the SOC depth distribution.•C accumulation was observed in conservation agriculture only in the first 30cm.•C accumulation was affected by mineral ...clay composition.•Conservation management led to higher polycondensed humic molecules content.•Soil tillage management did not affect microbial C and N contents.
Conservation agriculture is one of the agro-environment measures promoted by the Veneto Region (North-eastern Italy) to regulate and support many ecosystem services. This study compared conventional and conservation agriculture management systems in order to evaluate their effects on both SOC stocks and quality i.e. humic C and its molecular weight fractions, microbial C and N. The experiment was set up in 2010 on three farms in Veneto Region. In order to improve the monitoring procedures, a massive soil sampling programme was conducted in 2011 and 2014 in ca. 150 positions, considering the SOC stratification within a 0–50cm profile.
Results suggested that conservation agriculture practices affected SOC distribution rather than its total amount. The retention of crop residues on the soil surface and the absence of tillage operations drove SOC dynamics in the top layer (0–5cm) of the conservation system, while residues incorporation with ploughing was responsible for SOC accumulation at the 30–50cm depth in the conventional one. SOC stock variation in the conservation treatment was also influenced by root C input, which was identified as a major factor able to promote SOC accumulation in the 0–30cm profile. The role of clay on SOC dynamics was not uniform in the three farms since it depended both on the clay amount and its mineral composition. The strong interactions existing between management systems and local soil conditions were also confirmed by the C quality analyses.
This research did not demonstrate the benefits of conservation practices on SOC sequestration during the transition period. However, SOC sequestration is only one of the numerous ecosystem services provided by conservation practices. Some of these depend on the C content and quality in the top layers that, as demonstrated in our work, were strongly affected by the C stratification processes triggered by conservation agriculture.
Summary
The use of buffered soluble alendronate 70 mg effervescent tablet, a convenient dosing regimen for bisphosphonate therapy, seems a cost-effective strategy compared with relevant alternative ...treatments for postmenopausal women with osteoporosis aged 60 years and over in Italy.
Introduction
To assess the cost-effectiveness of buffered soluble alendronate (ALN) 70 mg effervescent tablet compared with relevant alternative treatments for postmenopausal osteoporotic women in Italy.
Methods
A previously validated Markov microsimulation model was adjusted to the Italian healthcare setting to estimate the lifetime costs (expressed in €2019) per quality-adjusted life-years (QALY) of buffered soluble ALN compared with generic ALN, denosumab, zoledronic acid and no treatment. Pooled efficacy data derived from the NICE network meta-analysis were used for bisphosphonate treatments. Two treatment duration scenarios were assessed: 1 year using persistence data derived from an Italian prospective observational study including 144 and 216 postmenopausal osteoporotic women on buffered soluble ALN and oral ALN, respectively, and 3 years. Analyses were conducted for women 60–80 years of age with a bone mineral density T-score ≤ − 3.0 or with existing vertebral fractures.
Results
In all simulated populations, buffered soluble ALN was dominant (more QALYs, lower costs) compared to denosumab. The cost per QALY gained of buffered soluble ALN compared to generic ALN and no treatment always falls below €20,000 per QALY gained. In the 1-year treatment scenario, zoledronic acid was associated with more QALY than buffered soluble ALN but the cost per QALY gained of zoledronic acid compared with buffered soluble ALN was always higher than €70,000, while buffered soluble ALN was dominant in the 3-year treatment scenario.
Conclusion
This study suggests that buffered soluble ALN represents a cost-effective strategy compared with relevant alternative treatments for postmenopausal osteoporosis women in Italy aged 60 years and over.
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