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The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons1. The atmospheric concentration of trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s2. A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased3,4. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown3. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.
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The Southern Ocean is a major sink of atmospheric CO2, but the nature and magnitude of its variability remains uncertain and debated. Estimates based on observations suggest substantial variability that is not reproduced by process-based ocean models, with increasingly divergent estimates over the past decade. We examine potential constraints on the nature and magnitude of climate-driven variability of the Southern Ocean CO2 sink from observation-based air-sea O2 fluxes. On interannual time scales, the variability in the air-sea fluxes of CO2 and O2 estimated from observations is consistent across the two species and positively correlated with the variability simulated by ocean models. Our analysis suggests that variations in ocean ventilation related to the Southern Annular Mode are responsible for this interannual variability. On decadal time scales, the existence of significant variability in the air-sea CO2 flux estimated from observations also tends to be supported by observation-based estimates of O2 flux variability. However, the large decadal variability in air-sea CO2 flux is absent from ocean models. Our analysis suggests that issues in representing the balance between the thermal and non-thermal components of the CO2 sink and/or insufficient variability in mode water formation might contribute to the lack of decadal variability in the current generation of ocean models. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.
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Digital dermatitis (DD) is the leading infectious cause of lameness in dairy cattle, and it affects their welfare and productivity worldwide. At the herd level, DD is often assessed while cows are standing in a milking parlor, and lesions are most commonly evaluated using the M-score. The objective of this study was to examine the interobserver agreement for M-scores of the feet of standing cattle, based on digital color photographs of dairy cattle hind feet. A total of 88 photographs and written descriptors of the M-score were sent to 11 scorers working at 10 different institutions in 5 countries. The scorers received no formal training immediately before scoring the photographs; however, all regularly used the M-score to score DD. The answers for 36 photographs were excluded from the analysis because the photograph either had more than 1 M-stage as mode or not all scorers assigned an M-score to it. The M-scores of the 11 scorers from 52 photographs were available for analysis. Interobserver agreement was tested using Gwet's agreement coefficient (AC1) and the mode was assumed correct. Overall, moderate agreement emerged for the M-score (AC1 = 0.48). For the individual M-stages, almost perfect agreement existed for M0 (AC1 = 0.99), M1 (AC1 = 0.92), and M3 (AC1 = 0.82), and substantial agreement for M2 (AC1 = 0.61), M4 (AC1 = 0.65), and M4.1 (AC1 = 0.71). This outcome indicates the degree of individual variation in M-scoring in this context by unstandardized, experienced European observers, particularly for the M2, M4, and M4.1 stages. Standardized training is likely to improve the consistency of M-scoring and thus the generalizability of future DD research results on this important endemic disease.
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Doenças dos Bovinos/patologia , Dermatite Digital/patologia , Doenças do Pé/veterinária , Coxeadura Animal/patologia , Variações Dependentes do Observador , Animais , Bovinos , Indústria de Laticínios , Feminino , Pé/patologia , Doenças do Pé/patologia , Casco e Garras/patologia , Leite , Fotografação/veterináriaRESUMO
Carbon tetrachloride (CCl4) is an ozone-depleting substance, accounting for about 10% of the chlorine in the troposphere. Under the terms of the Montreal Protocol, its production for dispersive uses was banned from 2010. In this work we show that, despite the controls on production being introduced, CCl4 emissions from the eastern part of China did not decline between 2009 and 2016. This finding is in contrast to a recent bottom-up estimate, which predicted a significant decrease in emissions after the introduction of production controls. We find eastern Asian emissions of CCl4 to be 16 (9-24) Gg/year on average between 2009 and 2016, with the primary source regions being in eastern China. The spatial distribution of emissions that we derive suggests that the source distribution of CCl4 in China changed during the 8-year study period, indicating a new source or sources of emissions from China's Shandong province after 2012.
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There are divergent opinions regarding the optimum surgical management of the axilla in patients with invasive breast cancer. Guidelines mandate axillary lymph node dissection (ALND) in the setting of positive sentinel lymph nodes. However, recent studies have questioned the true benefits of this procedure. Therefore, a meta-analysis of relevant randomized trials was performed in order to clarify the oncological benefit of axillary lymph node dissection. A comprehensive search of published randomized trials that compared patients with primary operable breast cancer with/without ALND was performed using MEDLINE, and available data were cross-referenced. Reviews of each study were conducted, and data were extracted. Primary outcomes were overall survival and recurrent axillary disease. A total of 7347 patients with operable primary breast cancer were identified from 8 randomised controlled trials comparing axillary recurrence in patients with or without ALND. Six of these trials provided data on overall survival on 6895 patients. Overall survival favours patients having ALND (OR = 1.22 (95% CI 1.03-1.44, p = 0.02). Similarly, patients undergoing ALND had increased recurrence-free survival (OR = 2.25 (95% CI 1.28-3.94, p = 0.0047). ALND appears to positively impact on overall and recurrence-free survival from breast cancer. These data highlight the enduring benefits of ALND in an era where adjuvant therapies are being promoted to manage regionally advanced/metastatic disease.
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Axila , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Excisão de Linfonodo , Neoplasias da Mama/mortalidade , Feminino , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Razão de Chances , Resultado do TratamentoRESUMO
BACKGROUND: Nipple-sparing mastectomy (NSM) is associated with improved cosmesis and is being performed increasingly. Its role in BRCA mutation carriers has not been well described. This was a study of the indications for, and outcomes of, NSM in BRCA mutation carriers. METHODS: BRCA mutation carriers who underwent NSM were identified. Details of patient demographics, surgical procedures, complications, and relevant disease stage and follow-up were recorded. RESULTS: A total of 177 NSMs were performed in 89 BRCA mutation carriers between September 2005 and December 2013. Twenty-six patients of median age 41 years had NSM for early-stage breast cancer and a contralateral prophylactic mastectomy. Mean tumour size was 1·4 (range 0·1-3·5) cm. Sixty-three patients of median age 39 years had prophylactic NSM, eight of whom had an incidental diagnosis of ductal carcinoma in situ. There were no local or regional recurrences in the 26 patients with breast cancer at a median follow-up of 28 (i.q.r. 15-43) months. There were no newly diagnosed breast cancers in the 63 patients undergoing prophylactic NSM at a median follow-up of 26 (11-42) months. All patients had immediate breast reconstruction. Five patients (6 per cent) required subsequent excision of the nipple-areola complex for oncological or other reasons. Skin desquamation occurred in 68 (38·4 per cent) of the 177 breasts, and most resolved without intervention. Debridement was required in 13 (7·3 per cent) of the 177 breasts, and tissue-expander or implant removal was necessary in six instances (3·4 per cent). CONCLUSION: NSM is an acceptable choice for patients with BRCA mutations, with no evidence of compromise to oncological safety at short-term follow-up. Complication rates were acceptable, and subsequent excision of the nipple-areola complex was rarely required.
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Carcinoma Intraductal não Infiltrante/cirurgia , Genes BRCA1 , Genes BRCA2 , Síndrome Hereditária de Câncer de Mama e Ovário/cirurgia , Mastectomia Subcutânea , Adulto , Carcinoma Intraductal não Infiltrante/genética , Feminino , Seguimentos , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Humanos , Mamoplastia/métodos , Pessoa de Meia-Idade , Mutação , Complicações Pós-Operatórias , Resultado do TratamentoRESUMO
Carbon dioxide off-setting policy in the agricultural sector is focused on manipulating the terrestrial carbon cycle by reafforestation and increasing the retention of carbon within agricultural soils. We quantified the amount of carbon stored in the living and dead biomass and the surface soils of a previously grazed woodland ecosystem. We demonstrate that modification of coarse woody debris management could potentially store 8 to 15 t C ha. This large carbon pool raises the prospect that appropriate management of temperate woodlands to retain coarse woody debris and increase its volume into the future could achieve increased landscape carbon storage.
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An important aspect of the rapidly growing field of quantum atom optics is exploring the behavior of ultracold atoms at a deeper level than the mean field approximation, where the quantum properties of individual atoms becomes important. Major recent advances have been achieved with the creation and detection of reliable single-atom sources, which is a crucial tool for testing fundamental quantum processes. Here, we create a source comprised of a single ultracold metastable helium atom, which enables novel free-space quantum atom optics experiments to be performed with single massive particles with large de Broglie wavelengths.
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A fundamental property of a three-dimensional Bose-Einstein condensate is long-range coherence; however, in systems of lower dimensionality, not only is the long-range coherence destroyed but additional states of matter are predicted to exist. One such state is a "transverse condensate," first predicted by van Druten and Ketterle [Phys. Rev. Lett. 79, 549 (1997)], in which the gas condenses in the transverse dimensions of a highly anisotropic trap while remaining thermal in the longitudinal dimension. Here, we detect the transition from a three-dimensional thermal gas to a gas undergoing transverse condensation by probing Hanbury Brown-Twiss correlations.
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Flocculated suspended sediments (flocs) are found in a variety of environments globally, and their transport and behavior bear substantial importance to several industries including fisheries, aquaculture, and shipping. Additionally, the modelling of their behavior is important for estuarine and coastal flood prediction and defence, and the process of flocculation occurs in other unrelated industries such as paper and chemical production. Floc porosity is conventionally assessed using inferential indirect or proxy data approaches. These methods underestimate floc porosity % by c. 30% and cannot measure the micro-scale complexity of these pore spaces and networks, rendering inputs to models sub-optimal. This study introduces a novel 3D porosity and pore space quantification protocol, that produces directly quantified porosity % and pore space data.â¢3D floc data from micro-CT scanning is segmented volumetricallyâ¢This segmented volume is quantified to extract porosity and several pore space parameters from the floc structure.
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Natural sediment flocs are fragile and highly heterogeneous aggregates of biogenic and minerogenic material typically with high porosity and low density. In aquatic environments dominated by fine, cohesive or mixed sediments they can dominate suspended sediment flux. Consequently, monitoring and modelling the behaviour, transport and distribution of flocs is very important for many aquatic industries, maintenance of waterways and conservation and management of aquatic waterbodies. Mathematical models that predict the behaviour of flocs rely on the accurate assessments of the size, shape, density, porosity and fractal dimension of flocs. These inherently 3-dimensional (3D) characteristics are typically derived from 2-dimensional (2D) data, largely due to the challenges associated with sampling, capturing, imaging and quantifying these fragile aggregates. We have developed new volumetric microscopy techniques which can quantify 3D internal and external structures and characteristics of sediment flocs. Here, these techniques were applied to quantify the 3D size (volume), shape and fractal dimension of natural and artificial sediment flocs and compare them to standard 2D approaches. Our study demonstrates that 2D approaches are under-estimating shape complexity and over-estimating the size and mass settling flux of flocs by up to two orders of magnitude, and the discrepancy between 2D and 3D is most marked for natural, organic rich macroflocs. Our study has significant implications for estimations of sediment flux at local to global scales within in aquatic environments. These new data and approaches offer the potential to improve the current parameterisation of sediment transport models and to improve the accuracy of current field-monitoring techniques.
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Floculação , Fractais , Sedimentos Geológicos , Sedimentos Geológicos/química , Modelos Teóricos , PorosidadeRESUMO
In direct analogy to the textbook example of light guided in a few-mode fiber (FMF), we report the observation of the first excited mode of an optically guided atomic beam. We selectively excite the atomic analog of the LP01 optical mode by controlling the energy distribution of ultracold atoms loaded into the guide, resulting in a modal structure dominated by a 47(2)% population in the first excited transverse mode. The ability to guide lower-order modes has been essential to demonstrating optical effects such as multimode interferometry, slow light, and entanglement, and an atomic analog to a FMF may lead to similarly useful applications.
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The recent identification of molecular components of the signal transduction pathway regulating activation of nuclear factor-kappaB (NF-kappaB) in response to cytokines such as tumor necrosis factor alpha and interleukin-1beta allows the evaluation of how other diverse stimuli impinge on the NF-kappaB activation pathway. These studies suggest a basis for specificity in activation of specific Rel-related family members and the genetic responses they promote.
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Regulação da Expressão Gênica/fisiologia , NF-kappa B/fisiologia , Transdução de Sinais/fisiologia , Transcrição Gênica/fisiologia , Sequência de Aminoácidos , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/fisiologia , Proteínas de Ligação a DNA/fisiologia , Desenvolvimento Embrionário e Fetal , Extremidades/embriologia , Proteínas I-kappa B , Inflamação/fisiopatologia , Camundongos , Camundongos Mutantes , Modelos Biológicos , Dados de Sequência Molecular , Morfogênese , Osteoclastos/citologia , Proteínas Quinases/fisiologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Estresse Fisiológico/fisiopatologiaRESUMO
The impacts of the partitioning of potentially toxic metals (PTM) within the estuarine environment is highly complex, but is of key significance owing to increases in populations living within such sensitive environments. Although empirical data exist for the partitioning of metals between the dissolved and particulate phases, little is known regarding the impacts of extracellular polymeric substances (EPS) upon the flocculation of particles within such a dynamic system nor the resultant influence on the distribution of metals between the particulate and dissolved phases. This prevents regulators from fully understanding the fate and risks associated with metals in estuaries. This study provides data associated with the simulation of 3 settlings typical of the turbulent mixing found in estuaries and partitioning of copper, cadmium, nickel, arsenic, lead and zinc for 3 salinities (0, 15, 30 PSU) reflecting the full salinity range from freshwater to seawater. Experiments were completed with and without the presence of EPS, using kaolin as the mineral particulate. The results showed significant differences between salinity, PTMs and turbulence for the experiments with and without EPS present. Overall, salinity was the main factor controlling the PTM partitioning to sediment, however the flocculation process did impact on the PTM distribution and with the addition of EPS the impact was more pronounced. The data highlighted the importance of taking account of EPS within any estuarine sediment process modelling, for relying on simple partitioning with corrections for salinity would likely lead to significant bias.
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Poluentes Ambientais , Poluentes Químicos da Água , Biopolímeros , Estuários , Floculação , Poluentes Químicos da Água/análiseRESUMO
We have used the Hanbury Brown-Twiss effect to directly compare the density correlations of a pulsed atom laser and a pulsed ultracold thermal source of metastable helium. It was found that the isotropic RF outcoupling of atoms from a Bose-Einstein condensate does not result in decoherence, while the 'bunching' typical of incoherent sources was observed for thermal atoms. This new method significantly increases data acquisition rates compared to previous measurements, and also permits future novel experiments which may allow us to probe processes such as the birth and death of a condensate by monitoring correlation effects.
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During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here, we show that the usual summer minimum in CO2 due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in Northern Europe. Notwithstanding, the CO2 transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO2 uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration inherited from the previous months due to the drought. For stations with sufficiently long time series, the CO2 anomaly observed in 2018 was compared to previous European droughts in 2003 and 2015. Considering the areas most affected by the temperature anomalies, we found a higher CO2 anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.
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Atmosfera/análise , Ciclo do Carbono , Dióxido de Carbono/análise , Secas , Ecossistema , Europa (Continente)RESUMO
AIMS/HYPOTHESIS: Common variants in the TCF7L2 gene are associated with type 2 diabetes via impaired insulin secretion. One hypothesis is that variation in TCF7L2 impairs insulin processing in the beta cell. In contrast, the association of related TCF7L2 polymorphisms with obesity is controversial in that it has only been shown in cohorts susceptible to ascertainment bias. We reproduced the association of diabetes-associated variants with proinsulin/insulin ratios, and also examined the association of a TCF7L2 haplotype with obesity in the Framingham Heart Study (FHS). METHODS: We genotyped the TCF7L2 single nucleotide polymorphisms rs7903146 and rs12255372 (previously associated with type 2 diabetes) and rs10885406 and rs7924080 (which tag haplotype A [HapA], a haplotype reported to be associated with obesity) in 2,512 FHS participants. We used age- and sex-adjusted linear mixed-effects models to test for association with glycaemic traits, proinsulin/insulin ratios and obesity measures. RESULTS: As expected, the T risk allele of rs7903146 was associated with higher fasting plasma glucose (p = 0.01). T/T homozygotes had a 23.5% increase in the proinsulin/insulin ratio (p = 1 x 10(-7)) compared with C/C homozygotes. There was no association of HapA with BMI (p = 0.98), waist circumference (p = 0.89), subcutaneous adipose tissue (p = 0.32) or visceral adipose tissue (p = 0.92). CONCLUSIONS/INTERPRETATION: We confirmed that the risk allele of rs7903146 is associated with hyperglycaemia and a higher proinsulin/insulin ratio. We did not detect any association of the TCF7L2 HapA with adiposity measures, suggesting that this may have been a spurious association from ascertainment bias, possibly induced by the evaluation of obesity in separate groups of glycaemic cases and controls.
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Variação Genética , Insulina/sangue , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Proinsulina/sangue , Fatores de Transcrição TCF/genética , Idoso , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/genética , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Proinsulina/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , Circunferência da CinturaRESUMO
For the female to be normally responsive to the display of wing vibrations by males, the arista and funiculus of the female's antenna must be intact and able to move freely. The arista probably acts as a sail, twisting the funiculus and thus stimulating units of Johnston's organ at its base.
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Comportamento Animal , Drosophila/fisiologia , Células Receptoras Sensoriais/fisiologia , Comportamento Sexual , Animais , Feminino , VibraçãoRESUMO
Activation of the transcription factor nuclear factor kappa B (NF-kappaB) is controlled by sequential phosphorylation, ubiquitination, and degradation of its inhibitory subunit IkappaB. A large multiprotein complex, the IkappaB kinase (IKK) signalsome, was purified from HeLa cells and found to contain a cytokine-inducible IkappaB kinase activity that phosphorylates IkappaB-alpha and IkappaB-beta. Two components of the IKK signalsome, IKK-1 and IKK-2, were identified as closely related protein serine kinases containing leucine zipper and helix-loop-helix protein interaction motifs. Mutant versions of IKK-2 had pronounced effects on RelA nuclear translocation and NF-kappaB-dependent reporter activity, consistent with a critical role for the IKK kinases in the NF-kappaB signaling pathway.
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Proteínas de Ciclo Celular , NF-kappa B/metabolismo , Fosfoproteínas Fosfatases , Proteínas Serina-Treonina Quinases/metabolismo , Clonagem Molecular , Fosfatase 1 de Especificidade Dupla , Ativação Enzimática , Células HeLa , Sequências Hélice-Alça-Hélice , Humanos , Quinase I-kappa B , Proteínas Imediatamente Precoces/metabolismo , Zíper de Leucina , Dados de Sequência Molecular , Fosforilação , Proteína Fosfatase 1 , Proteínas Tirosina Fosfatases/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por SubstratoRESUMO
Mature trees scattered throughout agricultural landscapes are critical habitat for some biota and provide a range of ecosystem services. These trees are declining in intensively managed agricultural landscapes globally. We developed a simulation model to predict the rates at which these trees are declining, identified the key variables that can be manipulated to mitigate this decline, and compared alternative management proposals. We used the initial numbers of trees in the stand, the predicted ages of these trees, their rate of growth, the number of recruits established, the frequency of recruitment, and the rate of tree mortality to simulate the dynamics of scattered trees in agricultural landscapes. We applied this simulation model to case studies from Spain, United States, Australia, and Costa Rica. We predicted that mature trees would be lost from these landscapes in 90-180 years under current management. Existing management recommendations for these landscapes--which focus on increasing recruitment--would not reverse this trend. The loss of scattered mature trees was most sensitive to tree mortality, stand age, number of recruits, and frequency of recruitment. We predicted that perpetuating mature trees in agricultural landscapes at or above existing densities requires a strategy that keeps mortality among established trees below around 0.5% per year, recruits new trees at a rate that is higher than the number of existing trees, and recruits new trees at a frequency in years equivalent to around 15% of the maximum life expectancy of trees. Numbers of mature trees in landscapes represented by the case studies will decline before they increase, even if strategies of this type are implemented immediately. This decline will be greater if a management response is delayed.