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1.
Sensors (Basel) ; 24(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894445

RESUMO

The detection of seismic activity precursors as part of an alarm system will provide opportunities for minimization of the social and economic impact caused by earthquakes. It has long been envisaged, and a growing body of empirical evidence suggests that the Earth's electromagnetic field could contain precursors to seismic events. The ability to capture and monitor electromagnetic field activity has increased in the past years as more sensors and methodologies emerge. Missions such as Swarm have enabled researchers to access near-continuous observations of electromagnetic activity at second intervals, allowing for more detailed studies on weather and earthquakes. In this paper, we present an approach designed to detect anomalies in electromagnetic field data from Swarm satellites. This works towards developing a continuous and effective monitoring system of seismic activities based on SWARM measurements. We develop an enhanced form of a probabilistic model based on the Martingale theories that allow for testing the null hypothesis to indicate abnormal changes in electromagnetic field activity. We evaluate this enhanced approach in two experiments. Firstly, we perform a quantitative comparison on well-understood and popular benchmark datasets alongside the conventional approach. We find that the enhanced version produces more accurate anomaly detection overall. Secondly, we use three case studies of seismic activity (namely, earthquakes in Mexico, Greece, and Croatia) to assess our approach and the results show that our method can detect anomalous phenomena in the electromagnetic data.

2.
Sci Rep ; 13(1): 12454, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528174

RESUMO

Tropical forest fragmentation from agricultural expansion alters the microclimatic conditions of the remaining forests, with effects on vegetation structure and function. However, little is known about how the functional trait variability within and among tree species in fragmented landscapes influence and facilitate species' persistence in these new environmental conditions. Here, we assessed potential changes in tree species' functional traits in riparian forests within six riparian forests in cropland catchments (Cropland) and four riparian forests in forested catchments (Forest) in southern Amazonia. We sampled 12 common functional traits of 123 species across all sites: 64 common to both croplands and forests, 33 restricted to croplands, and 26 restricted to forests. We found that forest-restricted species had leaves that were thinner, larger, and with higher phosphorus (P) content, compared to cropland-restricted ones. Tree species common to both environments showed higher intraspecific variability in functional traits, with leaf thickness and leaf P concentration varying the most. Species turnover contributed more to differences between forest and cropland environments only for the stem-specific density trait. We conclude that the intraspecific variability of functional traits (leaf thickness, leaf P, and specific leaf area) facilitates species persistence in riparian forests occurring within catchments cleared for agricultural expansion in Amazonia.


Assuntos
Florestas , Árvores , Agricultura , Fenótipo , Folhas de Planta
3.
Proc Natl Acad Sci U S A ; 119(51): e2210235119, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36516067

RESUMO

We report that high-quality single crystals of the hexagonal heavy fermion material uranium diauride (UAu2) become superconducting at pressures above 3.2 GPa, the pressure at which an unusual antiferromagnetic state is suppressed. The antiferromagnetic state hosts a marginal fermi liquid and the pressure evolution of the resistivity within this state is found to be very different from that approaching a standard quantum phase transition. The superconductivity that appears above this transition survives in high magnetic fields with a large critical field for all field directions. The critical field also has an unusual angle dependence suggesting that the superconductivity may have an order parameter with multiple components. An order parameter consistent with these observations is predicted to host half-quantum vortices (HQVs). Such vortices can be topologically entangled and have potential applications in quantum computing.

4.
Radiol Case Rep ; 17(9): 3456, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35909927

RESUMO

[This corrects the article DOI: 10.1016/j.radcr.2021.02.043.].

5.
Bio Protoc ; 12(11): e4441, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35799905

RESUMO

This protocol describes a method to assess relative changes in the level of global protein synthesis in the preimplantation embryo using the Click-iT ® Plus OPP Protein Synthesis Assays. In this assay, O-propargyl-puromycin (OPP), an analog of puromycin, is efficiently incorporated into the nascent polypeptide of newly translated proteins in embryonic cells. OPP is fluorescently labeled with a photostable Alexa Fluor TM dye and detected with fluorescence microscopy. The intensity of the fluorescence is quantitatively analyzed. This is a fast, sensitive, and non-radioactive method for the detection of protein synthesis in early embryo development. It provides a tool for analyzing the temporal regulation of protein synthesis, as well as the effects of changes in the embryonic microenvironment, and pharmacological and genetic modulations of embryo development. Graphical abstract: Figure 1. Brief overview of the procedures of the Click-iT ® Plus OPP Alexa Fluor ® protein synthesis assay in embryonic cells. (A) Set up OPP treatments: (1) Set up microdrops containing 50 µL of OPP working solution and label different treatments on the back of culture dishes ( e.g. , T0, T1, T2, and T3); (2) The drops are overlain with 2-3 mm heavy paraffin oil and then equilibrated in incubator for 2 h; (3) Collect the embryos from female reproductive tracts or following in vitro culture in desired treatments; (4) Culture embryos in the equilibrated OPP working solution for 2-6 h. ( B ) Example of OPP detection procedures working with 60-well plates labeled as T0, T1, T2, T3, T4, and T5 for different treatments: (1) The first 60-well plate is used for the procedures of washing, fixation, permeabilization, and Click-iT ® OPP detection. (2) The second 60-well plate is for DNA staining and washing. (C) Slide preparation: (1) Label the required number of slides and set up vaseline coverslip supports; (2) Add mounting medium; (3) Transfer embryos into mounting medium; (4) Set coverslip; (5) Seal the coverslip with nail polish.

6.
Radiol Case Rep ; 17(2): 364-367, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34925666

RESUMO

Congestive heart failure (CHF) patients have typical radiological features that assist in diagnosis. This is a case that demonstrates an atypical radiologic presentation for CHF which showed diffuse pulmonary nodules on CT. Diffuse nodules can be present in several disease processes and clinical correlation is a necessity for diagnosis. It is important for radiologists and clinicians to be aware of uncommon radiological features of CHF to avoid unnecessary procedures or treatments.

7.
Proc Natl Acad Sci U S A ; 118(49)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34873053

RESUMO

The term Fermi liquid is almost synonymous with the metallic state. The association is known to break down at quantum critical points (QCPs), but these require precise values of tuning parameters, such as pressure and applied magnetic field, to exactly suppress a continuous phase transition temperature to the absolute zero. Three-dimensional non-Fermi liquid states, apart from superconductivity, that are unshackled from a QCP are much rarer and are not currently well understood. Here, we report that the triangular lattice system uranium diauride (UAu2) forms such a state with a non-Fermi liquid low-temperature heat capacity [Formula: see text] and electrical resistivity [Formula: see text] far below its Néel temperature. The magnetic order itself has a novel structure and is accompanied by weak charge modulation that is not simply due to magnetostriction. The charge modulation continues to grow in amplitude with decreasing temperature, suggesting that charge degrees of freedom play an important role in the non-Fermi liquid behavior. In contrast with QCPs, the heat capacity and resistivity we find are unusually resilient in magnetic field. Our results suggest that a combination of magnetic frustration and Kondo physics may result in the emergence of this novel state.

8.
Arthroplast Today ; 11: 222-228, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34692959

RESUMO

BACKGROUND: Achieving accurate and consistent acetabular component orientation remains a major challenge in total hip arthroplasty. METHODS: We used a pelvic model to compare freehand techniques vs mechanical and anatomical alignment guides in achieving a target operative inclination (OI) and operative anteversion (OA). Thirty subjects comprising consultant orthopedic surgeons, orthopedic trainees, and nonsurgical staff positioned an acetabular component in a pelvic model using 3 different methods for guiding inclination and another 3 for guiding version. RESULTS: Using either a standard mechanical alignment guide (MAG) or a spirit level MAG technique eliminated outliers from target OI, while the freehand method resulted in 46.7% of measurements outside the OI target range. The spirit level MAG technique significantly outperformed the standard MAG technique in median unsigned deviation from target OI (0.8° vs 2.1°, P < .001). Either method of referencing the transverse acetabular ligament for version yielded lower deviations from target OA than the freehand method and fewer outliers from the ±5° target range. Surgical experience was not a significant factor for accurately achieving target OI and OA. CONCLUSIONS: Even in an idealized in vitro model, a wide range of OI and OA is seen with the freehand technique of cup placement by subjects of all levels of surgical experience. Using either a standard MAG or a spirit level MAG reduces deviations in target OI, with the spirit level MAG method yielding the best accuracy. Using the transverse acetabular ligament to guide cup anteversion yields more accurate OA.

9.
Ecol Appl ; 31(8): e02455, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34523195

RESUMO

Urbanization has a homogenizing effect on biodiversity and leads to communities with fewer native species and lower conservation value. However, few studies have explored whether or how land management by urban residents can ameliorate the deleterious effects of this homogenization on species composition. We tested the effects of local (land management) and neighborhood-scale (impervious surface and tree canopy cover) features on breeding bird diversity in six US metropolitan areas that differ in regional species pools and climate. We used a Bayesian multiregion community model to assess differences in species richness, functional guild richness, community turnover, population vulnerability, and public interest in each bird community in six land management types: two natural area park types (separate and adjacent to residential areas), two yard types with conservation features (wildlife-certified and water conservation) and two lawn-dominated yard types (high- and low-fertilizer application), and surrounding neighborhood-scale features. Species richness was higher in yards compared with parks; however, parks supported communities with high conservation scores while yards supported species of high public interest. Bird communities in all land management types were composed of primarily native species. Within yard types, species richness was strongly and positively associated with neighborhood-scale tree canopy cover and negatively associated with impervious surface. At a continental scale, community turnover between cities was lowest in yards and highest in parks. Within cities, however, turnover was lowest in high-fertilizer yards and highest in wildlife-certified yards and parks. Our results demonstrate that, across regions, preserving natural areas, minimizing impervious surfaces and increasing tree canopy are essential strategies to conserve regionally important species. However, yards, especially those managed for wildlife support diverse, heterogeneous bird communities with high public interest and potential to support species of conservation concern. Management approaches that include the preservation of protected parks, encourage wildlife-friendly yards and acknowledge how public interest in local birds can advance successful conservation in American residential landscapes.


Assuntos
Aves , Ecossistema , Animais , Teorema de Bayes , Biodiversidade , Conservação dos Recursos Naturais , Urbanização
10.
Phys Rev Lett ; 126(19): 197203, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34047591

RESUMO

The theory of quantum order-by-disorder (QOBD) explains the formation of modulated magnetic states at the boundary between ferromagnetism and paramagnetism in zero field. PrPtAl has been argued to provide an archetype for this. Here, we report the phase diagram in magnetic field, applied along both the easy a axis and hard b axis. For field aligned to the b axis, we find that the magnetic transition temperatures are suppressed and at low temperature there is a single modulated fan state, separating an easy a axis ferromagnetic state from a field polarized state. This fan state is well explained with the QOBD theory in the presence of anisotropy and field. Experimental evidence supporting the QOBD explanation is provided by the large increase in the T^{2} coefficient of the resistivity and direct detection of enhanced magnetic fluctuations with inelastic neutron scattering, across the field range spanned by the fan state. This shows that the QOBD mechanism can explain field induced modulated states that persist to very low temperature.

11.
Development ; 148(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34013332

RESUMO

Eukaryotic translation initiation factor 4E (eIF4E) mediates cap-dependent translation. Genetic and inhibitor studies show that eIF4E expression is required for the successful transition from maternal to embryonic control of mouse embryo development. eIF4E was present in the oocyte and in the cytoplasm soon after fertilization and during each stage of early development. Functional knockout (Eif4e-/-) by PiggyBac [Act-RFP] transposition resulted in peri-implantation embryonic lethality because of the failure of normal epiblast formation. Maternal stores of eIF4E supported development up to the two- to four-cell stage, after which new expression occurred from both maternal and paternal inherited alleles. Inhibition of the maternally acquired stores of eIF4E (using the inhibitor 4EGI-1) resulted in a block at the two-cell stage. eIF4E activity was required for new protein synthesis in the two-cell embryo and Eif4e-/- embryos had lower translational activity compared with wild-type embryos. eIF4E-binding protein 1 (4E-BP1) is a hypophosphorylation-dependent negative regulator of eIF4E. mTOR activity was required for 4E-BP1 phosphorylation and inhibiting mTOR retarded embryo development. Thus, this study shows that eIF4E activity is regulated at key embryonic transitions in the mammalian embryo and is essential for the successful transition from maternal to embryonic control of development.


Assuntos
Desenvolvimento Embrionário/genética , Fator de Iniciação 4E em Eucariotos/genética , Regulação da Expressão Gênica no Desenvolvimento , Animais , Elementos de DNA Transponíveis , Embrião de Mamíferos , Fator de Iniciação 4E em Eucariotos/metabolismo , Imunofluorescência , Camundongos , Camundongos Knockout , Oócitos/metabolismo , Biossíntese de Proteínas
12.
Radiol Case Rep ; 16(6): 1391-1394, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33912253

RESUMO

Mesenchymal tumors make up only about 1% of primary GI tumors, with Gastrointestinal Stromal Tumors (GIST) being the most common nonepithelial GI neoplasms. They are derived from the Interstitial cells of Cajal (ICC), and occur predominantly in older individuals, with a mean age of diagnosis of 64 years. Here we discuss the case of a 39-year-old female with atypical thoracic back pain wrapping around to the front and migrating diffuse abdomen pain that sometimes radiates into the chest. Upon imaging, a gastric GIST of the greater curve of the stomach was found incidentally on investigation of a pancreatic mass that was revealed to be a co-occurring pancreatic neuroendocrine tumor. For management of the gastric GIST and pancreatic neuroendocrine tumor, this patient underwent partial gastrectomy with gastrojejunostomy, partial pancreatectomy, splenectomy, and cholecystectomy with no complications.

13.
Radiol Case Rep ; 16(5): 1165-1168, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33777281

RESUMO

An ectopic pregnancy is the implantation of a fertilized ovum in a location other than the main cavity of the uterus. Ectopic pregnancies are reported in approximately 1%-2% of pregnancies, and while 95% of ectopic pregnancies are in fallopian tubes, only 3% are in ovarian, cervical, or abdominal sites. We present a case of a 38-year-old female with acute onset of severe lower abdominal pain, sepsis, chills, and diarrhea who was evaluated with a CT of the abdomen and pelvis with IV contrast only. The imaging revealed a likely second trimester age fetal skeleton with a partially collapsed calvarium within the peritoneal cavity and an abnormal complex cystic lesion in the right adnexal area. In this case, the patient successfully underwent exploratory laparotomy with removal of both the abdominal ectopic pregnancy and the tubo-ovarian mass.

14.
Sci Data ; 8(1): 76, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674581

RESUMO

The Buzzards Bay Coalition's Baywatchers Monitoring Program (Baywatchers) collected summertime water quality information at more than 150 stations around Buzzards Bay, Massachusetts from 1992 to 2018. Baywatchers documents nutrient-related water quality and the effects of nitrogen pollution. The large majority of stations are located in sub-estuaries of the main Bay, although stations in central Buzzards Bay and Vineyard Sound were added beginning in 2007. Measurements include temperature, salinity, Secchi depth and concentrations of dissolved oxygen, ammonium, nitrate + nitrite, total dissolved nitrogen, particulate organic nitrogen, particulate organic carbon, ortho-phosphate, chlorophyll a, pheophytin a, and in lower salinity waters, total phosphorus and dissolved organic carbon. The Baywatchers dataset provides a long-term record of the water quality of Buzzards Bay and its sub-estuaries. The data have been used to identify impaired waters, evaluate discharge permits, support the development of nitrogen total maximum daily loads, develop strategies for reducing nitrogen inputs, and increase public awareness and generate support for management actions to control nutrient pollution and improve water quality.

15.
Ecology ; 102(1): e03211, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32981087

RESUMO

High rates of biological nitrogen fixation (BNF) are commonly reported for tropical forests, but most studies have been conducted in regions that receive substantial inputs of molybdenum (Mo) from atmospheric dust and sea-salt aerosols. Even in these regions, the low availability of Mo can constrain free-living BNF catalyzed by heterotrophic bacteria and archaea. We hypothesized that in regions where atmospheric inputs of Mo are low and soils are highly weathered, such as the southeastern Amazon, Mo would constrain BNF. We also hypothesized that the high soil acidity, characteristic of the Amazon Basin, would further constrain Mo availability and therefore soil BNF. We conducted two field experiments across the wet and dry seasons, adding Mo, phosphorus (P), and lime alone and in combination to the forest floor in the southeastern Amazon. We sampled soils and litter immediately, and then weeks and months after the applications, and measured Mo and P availability through resin extractions and BNF with the acetylene reduction assay. The experimental additions of Mo and P increased their availability and the lime increased soil pH. While the combination of Mo and P increased BNF at some time points, BNF rates did not increase strongly or consistently across the study as a whole, suggesting that Mo, P, and soil pH are not the dominant controls over BNF. In a separate short-term laboratory experiment, BNF did not respond strongly to Mo and P even when labile carbon was added. We postulate that high nitrogen (N) availability in this area of the Amazon, as indicated by the stoichiometry of soils and vegetation and the high nitrate soil stocks, likely suppresses BNF at this site. These patterns may also extend across highly weathered soils with high N availability in other topographically stable regions of the tropics.


Assuntos
Fixação de Nitrogênio , Fósforo , Brasil , Florestas , Concentração de Íons de Hidrogênio , Molibdênio , Nitrogênio , Solo , Árvores , Clima Tropical
16.
J Environ Manage ; 275: 111132, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002703

RESUMO

Local regulations on residential landscapes (yards and gardens) can facilitate or constrain ecosystem services and disservices in cities. To our knowledge, no studies have undertaken a comprehensive look at how municipalities regulate residential landscapes to achieve particular goals and to control management practices. Across six U.S. cities, we analyzed 156 municipal ordinances to examine regional patterns in local landscape regulations and their implications for sustainability. Specifically, we conducted content analysis to capture regulations aimed at: 1) goals pertaining to conservation and environmental management, aesthetics and nuisance avoidance, and health and wellbeing, and 2) management actions including vegetation maintenance, water and waste management, food production, and chemical inputs. Our results reveal significant variation in local and regional regulations. While regulatory goals stress stormwater management and nuisance avoidance, relatively few municipalities explicitly regulate residential yards to maintain property values, mitigate heat, or avoid allergens. Meanwhile, biological conservation and water quality protection are common goals, yet regulations on yard management practices (e.g., non-native plants or chemical inputs) sometimes contradict these purposes. In addition, regulations emphasizing aesthetics and the maintenance of vegetation, mowing of grass and weeds, as well as the removal of dead wood, may inhibit wildlife-friendly yards. As a whole, landscaping ordinances largely ignore tradeoffs between interacting goals and outcomes, thereby limiting their potential to support landscape sustainability. Recommendations therefore include coordinated, multiobjective planning through partnerships among planners, developers, researchers, and non-government entities at multiple scales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Cidades , Jardinagem , Plantas
17.
ACS Infect Dis ; 6(11): 2959-2969, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32960047

RESUMO

The continued emergence and spread of antimicrobial resistance (AMR), particularly multidrug resistant (MDR) bacteria, are increasing threats driving the search for additional and alternative antimicrobial agents. The World Health Organization (WHO) has categorized bacterial risk levels and includes Escherichia coli among the highest priority, making this both a convenient model bacterium and a clinically highly relevant species on which to base investigations of antimicrobials. Among many compounds examined for use as antimicrobials, Ga(III) complexes have shown promise. Nonetheless, the spectrum of activities, susceptibility of bacterial species, mechanisms of antimicrobial action, and bacterial characteristics influencing antibacterial actions are far from being completely understood; these are important considerations for any implementation of an effective antibacterial agent. In this investigation, we show that an alteration in growth conditions to physiologically relevant lowered oxygen (anaerobic) conditions substantially increases the minimum inhibitory concentrations (MICs) of Ga(III) required to inhibit growth for 46 wild-type E. coli strains. Several studies have implicated a Trojan horse hypothesis wherein bacterial Fe uptake systems have been linked to the promotion of Ga(III) uptake and result in enhanced antibacterial activity. Our studies show that, conversely, the carriage of accessory Fe uptake systems (Fe_acc) significantly increased the concentrations of Ga(III) required for antibacterial action. Similarly, it is shown that MDR strains are more resistant to Ga(III). The increased tolerance of Fe_acc/MDR strains was apparent under anaerobic conditions. This phenomenon of heightened tolerance has not previously been shown although the mechanisms remain to be defined. Nonetheless, this further highlights the significant contributions of bacterial metabolism, fitness, and AMR characteristics and their implications in evaluating novel antimicrobials.


Assuntos
Anti-Infecciosos , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Compostos Férricos , Oxigênio
18.
J Phys Condens Matter ; 32(41): 415602, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32531764

RESUMO

A better understanding of the synthesis conditions, composition and physical properties of UTe2 are required to interpret previously reported unconventional superconductivity. Here we report how the superconducting properties of single crystals depend on the ratio of elements present in their synthesis by chemical vapour transport. We have obtained crystals with the highest reported ambient pressure T c and a larger superconducting heat capacity jump from a growth with a U:Te ratio different from that widely used in the literature. For these crystals, the ratio of residual heat capacity in the superconducting state to that of the normal state, γ*/γ N, is significantly lower than 0.5, reported elsewhere. An upturn in the heat capacity below 200 mK is also reduced compared to other studies and is well described by a Schottky anomaly and residual Sommerfeld term rather than quantum critical behaviour.

19.
Cell Rep ; 30(6): 1670-1681.e7, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32049001

RESUMO

Reproductive aging in female mammals is an irreversible process associated with declining oocyte quality, which is the rate-limiting factor to fertility. Here, we show that this loss of oocyte quality with age accompanies declining levels of the prominent metabolic cofactor nicotinamide adenine dinucleotide (NAD+). Treatment with the NAD+ metabolic precursor nicotinamide mononucleotide (NMN) rejuvenates oocyte quality in aged animals, leading to restoration in fertility, and this can be recapitulated by transgenic overexpression of the NAD+-dependent deacylase SIRT2, though deletion of this enzyme does not impair oocyte quality. These benefits of NMN extend to the developing embryo, where supplementation reverses the adverse effect of maternal age on developmental milestones. These findings suggest that late-life restoration of NAD+ levels represents an opportunity to rescue female reproductive function in mammals.


Assuntos
Fertilidade/genética , NAD/metabolismo , Envelhecimento , Animais , Feminino , Camundongos , Camundongos Transgênicos
20.
Glob Chang Biol ; 26(3): 1668-1680, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31984585

RESUMO

Fertilized temperate croplands export large amounts of reactive nitrogen (N), which degrades water and air quality and contributes to climate change. Fertilizer use is poised to increase in the tropics, where widespread food insecurity persists and increased agricultural productivity will be needed, but much less is known about the potential consequences of increased tropical N fertilizer application. We conducted a meta-analysis of tropical field studies of nitrate leaching, nitrous oxide emissions, nitric oxide emissions, and ammonia volatilization totaling more than 1,000 observations. We found that the relationship between N inputs and losses differed little between temperate and tropical croplands, although total nitric oxide losses were higher in the tropics. Among the potential drivers we studied, the N input rate controlled all N losses, but soil texture and water inputs also controlled hydrological N losses. Irrigated systems had significantly higher losses of ammonia, and pasture agroecosystems had higher nitric oxide losses. Tripling of fertilizer N inputs to tropical croplands from 50 to 150 kg N ha-1  year-1 would have substantial environmental implications and would lead to increases in nitrate leaching (+30%), nitrous oxide emissions (+30%), nitric oxide (+66%) emissions, and ammonia volatilization (+74%), bringing tropical agricultural nitrate, nitrous oxide, and ammonia losses in line with temperate losses and raising nitric oxide losses above them.


Assuntos
Agricultura , Nitrogênio , Fertilizantes , Óxido Nitroso , Solo
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