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31.
Increasing aridity reduces soil microbial diversity and abundance in global drylands 总被引:1,自引:0,他引:1
Fernando T. Maestre Manuel Delgado-Baquerizo Thomas C. Jeffries David J. Eldridge Victoria Ochoa Beatriz Gozalo José Luis Quero Miguel García-Gómez Antonio Gallardo Werner Ulrich Matthew A. Bowker Tulio Arredondo Claudia Barraza-Zepeda Donaldo Bran Adriana Florentino Juan Gaitán Julio R. Gutiérrez Elisabeth Huber-Sannwald Mohammad Jankju Rebecca L. Mau Maria Miriti Kamal Naseri Abelardo Ospina Ilan Stavi Deli Wang Natasha N. Woods Xia Yuan Eli Zaady Brajesh K. Singh 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(51):15684-15689
Soil bacteria and fungi play key roles in the functioning of terrestrial ecosystems, yet our understanding of their responses to climate change lags significantly behind that of other organisms. This gap in our understanding is particularly true for drylands, which occupy ∼41% of Earth´s surface, because no global, systematic assessments of the joint diversity of soil bacteria and fungi have been conducted in these environments to date. Here we present results from a study conducted across 80 dryland sites from all continents, except Antarctica, to assess how changes in aridity affect the composition, abundance, and diversity of soil bacteria and fungi. The diversity and abundance of soil bacteria and fungi was reduced as aridity increased. These results were largely driven by the negative impacts of aridity on soil organic carbon content, which positively affected the abundance and diversity of both bacteria and fungi. Aridity promoted shifts in the composition of soil bacteria, with increases in the relative abundance of Chloroflexi and α-Proteobacteria and decreases in Acidobacteria and Verrucomicrobia. Contrary to what has been reported by previous continental and global-scale studies, soil pH was not a major driver of bacterial diversity, and fungal communities were dominated by Ascomycota. Our results fill a critical gap in our understanding of soil microbial communities in terrestrial ecosystems. They suggest that changes in aridity, such as those predicted by climate-change models, may reduce microbial abundance and diversity, a response that will likely impact the provision of key ecosystem services by global drylands.Climate change is a major driver of biodiversity loss from local to global scales, in both terrestrial and aquatic ecosystems (1, 2). Given the dependence of crucial ecosystem processes and services on biodiversity (3–5), climate-change-driven biodiversity losses will dramatically alter the functioning of natural ecosystems (4, 6). Key ecosystem processes—such as nutrient cycling, carbon (C) sequestration, and organic matter decomposition—depend on soil bacteria and fungi (7–9). However, we have limited knowledge of the role of climatic factors as drivers of their abundance and diversity at regional and global scales (10–12). This gap in our understanding is particularly true for drylands, areas with an aridity index (precipitation/potential evapotranspiration ratio) below 0.65 (13), which are among the most sensitive ecosystems to climate change (14). Drylands are expected to expand in global area by 11–23% by 2100 (15), experiencing increased aridity and reduced soil moisture (16). Land degradation and desertification already affect ∼250 million people in the developing world (17). Altered climate and the growth of human populations will almost inevitably exacerbate these problems in drylands (14, 17). Because the provisioning of ecosystem services essential for human development (e.g., soil fertility, food, and biomass production) heavily relies on the abundance, composition, and diversity of soil fungi and bacteria (18, 19), it is crucial to understand how changes in aridity affect soil microbial communities. Drylands, however, are poorly represented in global soil bacteria and fungi databases (10–12, 20), and no field study has simultaneously examined how the abundance, composition, and diversity of these organisms vary along aridity gradients in drylands worldwide.Here, we present a global field study conducted across 80 dryland sites from all continents, except Antarctica (Fig. S1), to assess how changes in aridity, as defined by the aridity index, affect the total abundance and diversity of soil bacteria and fungi and the relative abundance of major bacterial and fungal taxa. The studied ecosystems encompass a wide variety of the climatic, edaphic, and vegetation conditions found in drylands worldwide (Materials and Methods). We predict that increases in aridity should reduce the abundance and diversity of soil bacteria and fungi due to the negative relationships typically found between aridity and the availability of resources such as water and C (21), which largely drive soil microbial abundance and activity in drylands (22–24). To test this hypothesis, we characterized bacterial and fungal communities in the soil surface (top 7.5 cm) along natural aridity gradients by using Illumina Miseq profiling of ribosomal genes and internal transcribed spacer (ITS) markers, quantified bacterial and fungal abundances with quantitative PCR (qPCR), and gathered information on multiple biotic and abiotic factors known to influence soil microbes (Fig. S2).Open in a separate windowFig. S1.Location of the 80 sites used in this study. Some of them overlap and are thus indistinguishable. Exact locations and additional site characteristics are provided in figshare (DOI 10.6084/m9.figshare.1487693).Open in a separate windowFig. S2.A priori SEM used in this study. Spatial is a composite variable formed by latitude and longitude. MDR, mean diurnal temperature range (mean of monthly differences between maximum and minimum temperature). The numbers in the arrows denote example references used to support our predictions, which can be found in the reference list. 相似文献
32.
@Note: A workbench for Biomedical Text Mining 总被引:1,自引:0,他引:1
Anlia Loureno Rafael Carreira Snia Carneiro Paulo Maia Daniel Glez-Pea Florentino Fdez-Riverola Eugnio C. Ferreira Isabel Rocha Miguel Rocha 《Journal of biomedical informatics》2009,42(4):710-720
Biomedical Text Mining (BioTM) is providing valuable approaches to the automated curation of scientific literature. However, most efforts have addressed the benchmarking of new algorithms rather than user operational needs. Bridging the gap between BioTM researchers and biologists’ needs is crucial to solve real-world problems and promote further research.We present @Note, a platform for BioTM that aims at the effective translation of the advances between three distinct classes of users: biologists, text miners and software developers. Its main functional contributions are the ability to process abstracts and full-texts; an information retrieval module enabling PubMed search and journal crawling; a pre-processing module with PDF-to-text conversion, tokenisation and stopword removal; a semantic annotation schema; a lexicon-based annotator; a user-friendly annotation view that allows to correct annotations and a Text Mining Module supporting dataset preparation and algorithm evaluation.@Note improves the interoperability, modularity and flexibility when integrating in-home and open-source third-party components. Its component-based architecture allows the rapid development of new applications, emphasizing the principles of transparency and simplicity of use. Although it is still on-going, it has already allowed the development of applications that are currently being used. 相似文献
33.
Silove D Manicavasagar V Baker K Mausiri M Soares M de Carvalho F Soares A Fonseca Amiral Z 《The Australian and New Zealand journal of psychiatry》2004,38(11-12):929-932
OBJECTIVE: Little is known about the profile of patients treated in mental health services in low-income, post-conflict countries, especially in the post-emergency phase. We postulated that patients attending the first community mental health service in East Timor would be characterized not only by mental disturbance but by high levels of social vulnerability. METHOD: Drawing on existing methods and on consultations with East Timorese mental health staff, five social indicators were identified: dangerousness; inability to undertake life-sustaining self-care; bizarre behaviour; incapacitating distress; and social unmanageability. Adequate levels of interrater reliability (65-91%) were achieved in identifying these indicators from case notes. Forty-eight randomly selected case notes were analyzed to ascertain the prevalence of social risk factors as well as the referral source and broad diagnostic groupings. RESULTS: Major referral sources were the family, humanitarian agencies and the police. Twenty-nine percent met criteria for dangerousness; 42% for inability to undertake self-care; 58% for bizarre behaviour; 75% for distress; and 19% for unmanageability. Ninety-eight percent fulfilled at least one social indicator, with the modal score being 2. CONCLUSIONS: Although the approach to documentation and analysis was preliminary, the data suggest that a focus on social risk indicators may assist in determining those mentally disturbed persons in need of priority care in resource-poor post-conflict countries. 相似文献
34.
35.
Armando D. Martínez-Iniesta Aarn Morelos-Gmez Emilio Muoz-Sandoval Florentino Lpez-Urías 《RSC advances》2021,11(5):2793
Onion-like graphitic structures are of great importance in different fields. Pentagons, heptagons, and octagons are essential features of onion-like graphitic structures that could generate important properties for diverse applications such as anodes in Li metal batteries or the oxygen reduction reaction. These carbon nanomaterials are fullerenes organized in a nested fashion. In this work, we produced graphitic nano onion-like structures containing phosphorus and nitrogen (NP-GNOs), using the aerosol assisted chemical vapor deposition method. The NP-GNOs were grown at high temperature (1020 °C) using ferrocene, trioctylphosphine oxide, benzylamine, and tetrahydrofuran precursors. The morphology, structure, composition, and surface chemistry of NP-GNOs were characterized using different techniques. The NP-GNOs showed diameters of 110–780 nm with Fe-based nanoparticles inside. Thermogravimetric analysis showed that NP-GNOs are thermally stable with an oxidation temperature of 724 °C. The surface chemistry analysis by FTIR and XPS revealed phosphorus–nitrogen codoping, and several functionalities containing C–H, N–H, P–H, P–O, P O, C O, and C–O bonds. We show density functional theory calculations of phosphorus–nitrogen doping and functionalized C240 fullerenes. We present the optimized structures, electronic density of states, HOMO, and LUMO wave functions for P-doped and OH-functionalized fullerenes. The P O and P–O bonds attributed to phosphates or hydroxyl groups attached to phosphorus atoms doping the NP-GNOs could be useful in improving supercapacitor function.Nitrogen–phosphorus doped graphitic nano onion-like structures. 相似文献
36.
Florentino Luciano Caetano dos Santos Atte Joutsen Michelangelo Paci Juha Salenius Hannu Eskola 《The international journal of cardiovascular imaging》2016,32(8):1299-1310
Atherosclerosis is one of the leading causes of mortality in the western world. Computed tomography angiography (CTA) is the conventional imaging method used for pre-surgery assessment of the blood flow within the carotid vessel. In this paper, we present a proof of concept of a novel, fast and operator independent protocol for the automatic detection (seeding) of the carotid arteries in CTA in the thorax and upper neck region. The dataset is composed of 14 patients’ CTA images of the neck region. The performance of this method is compared with manual seeding by four trained operators. Inter-operator variation is also assessed based on the dataset. The minimum, average and maximum coefficient of variation among the operators was (0, 2, 5?%), respectively. The performance of our method is comparable with the state of the art alternative, presenting a detection rate of 75 and 71?% for the lowest and uppermost image levels, respectively. The mean processing time is 167 s per patient versus 386 s for manual seeding. There are no significant differences between the manual and automatic seed positions in the volumes (p?=?0.29). A fast, operator independent protocol was developed for the automatic detection of carotid arteries in CTA. The results are encouraging and provide the basis for the creation of automatic detection and analysis tools for carotid arteries. 相似文献
37.
de Almeida Aline Dias Silva Irismara Sousa Fernandes-Braga Weslley LimaFilho Antônio Carlos Melo Florentino R odrigo Machado Barra Ayslan de Oliveira Andrade Luciana Leite M. Fátima Cassali Geovanni Dantas Klein André 《Inflammation research》2020,69(10):1059-1070
Inflammation Research - This study aims to investigate the role of protease-activated receptor (PAR) 2 and mast cell (MC) tryptase in LPS-induced lung inflammation and neutrophil recruitment in the... 相似文献
38.
Joan Oliva Arjie Florentino Fawzia Bardag‐Gorce Yutaka Niihara 《Journal of tissue engineering and regenerative medicine》2019,13(7):1153-1163
Shipping time and shipping delays might affect the quality of the stem cells based engineered “organs.” In our laboratory, we have developed a limbal stem cell deficient (LSCD) rabbit model. To reverse the LSCD, we cultured oral mucosal epithelial cells for 2–3 weeks and engineered cultured autologous oral mucosa epithelial cell sheets (CAOMECS), which were grafted on the LSCD cornea. The purpose of this study was to vitrify CAOMECS and to store it until the CAOMECS can be grafted onto patients. CAOMECS were vitrified in LN2 for up to 204 days. We tested two different methods of vitrification with different solutions; however, CAOMECS were only viable when they were not stored in a vitrification solution; results were only reported from this CAOMECS. On the basis of hematoxylin and eosin staining, we showed that the CAOMECS morphology was well preserved after long‐term storage in LN2. Most of the preservation solutions maintained the CAOMECS phenotype (Ki67, proliferating cell nuclear antigen (PCNA), Beta‐Catenin, ZO‐1, E‐Cadherin, CK3, CK4, CK13). The exception was the solution composed with ethylene glycol and Dimethyl sulfoxide (DMSO): this resulted in loss of DeltaN‐p63 expression. DeltaN‐p63 is an important marker for cell proliferation. The expression of proteins involved in cell–cell connection and the differentiation markers were maintained. Apoptosis was not detected in the thawed CAOMECS. We demonstrated that CAOMECS can be stored long‐term in LN2 without affecting their morphology and phenotype. 相似文献
39.
Olveira-Fuster G Olvera-Márquez P Carral-Sanlaureano F González-Romero S Aguilar-Diosdado M Soriguer-Escofet F 《Diabetes care》2004,27(8):1904-1909
OBJECTIVE: The goal of this study was to estimate the excess hospitalizations, hospital days, and inpatient costs attributable to diabetes in Andalusia, Spain (37 hospitals, 7,236,459 inhabitants), during 1999 compared with those without diabetes. RESEARCH DESIGN AND METHODS: This study was an analysis of all hospital discharges. Those with an ICD-9-CM code of 250 as either the main or secondary diagnosis were considered to have been admissions of individuals with diabetes. An estimate of costs was applied to each inpatient admission by assigning a cost weight based on the diagnostic-related group (DRG) related to each admission. RESULTS: A total of 538,580 admissions generated 4,310,654 hospital bed-days and total costs of 940,026,949 euro. People with diabetes accounted for 9.7% of all hospital discharges, 13.8% of total stays, and 14.1% of the total cost. Of the total cost for individuals with diabetes (132,509,217 euro), 58.3% were excess costs, of which 47% was attributable to cardiovascular complications and 43% to admissions for comorbid diseases. Individuals 45-75 years of age accounted for 75% of the excess costs. The rate of admissions during the study year was 145 per 1,000 inhabitants for individuals with diabetes compared with 70 admissions per 1,000 inhabitants for individuals without diabetes. CONCLUSIONS: The costs arising from hospitalization of individuals with diabetes are disproportionate in relation to their prevalence. For those aged >or=45 years, cardiovascular complications were clearly the most important factor determining increased costs from diabetes. 相似文献
40.
Galdino PM Nascimento MV Florentino IF Lino RC Fajemiroye JO Chaibub BA de Paula JR de Lima TC Costa EA 《Progress in neuro-psychopharmacology & biological psychiatry》2012,38(2):276-284
Spiranthera odoratissima A. St. Hil. (manacá) is used in folk medicine to treat renal and hepatic diseases, stomachache, headaches and rheumatism. A central nervous system (CNS) depressant effect of the hexane fraction from the ethanolic extract of this plant has been described. β-caryophyllene, the main component of this essential oil, is a sesquiterpene compound with anti-inflammatory properties that has been found in essential oils derived from several medicinal plants. This work is aimed to evaluate the pharmacological activity of the essential oil obtained from S. odoratissima leaves (EO) and its major component on the murine CNS; we aimed to evaluate a possible anxiolytic-like effect and the underlying mechanisms involved. In an open field test, EO (500 mg/kg) and β-caryophyllene (50, 100 and 200 mg/kg) increased the crossing frequency (P<0.05) and, EO (250 and 500 mg/kg) and β-caryophyllene (200 mg/kg) increased the time spent in the center (P<0.05) without altering total crossings of the open field. EO and β-caryophyllene did not alter the number of falls in the rota-rod test (P>0.05). In the pentobarbital-induced sleep test, EO (500 mg/kg) and β-caryophyllene (200 and 400 mg/kg) decreased the latency to sleep (P<0.05), and EO (125, 250 and 500 mg/kg) (P<0.001) and β-caryophyllene (200 and 400 mg/kg) (P<0.05 and P<0.001) increased the sleep time. In anxiety tests, EO (500 mg/kg) and β-caryophyllene (100 and 200 mg/kg) increased head-dipping behavior (P<0.05) in the hole-board test, entries (P<0.05) into and time spent (P<0.05) on the open arms of the elevated plus maze (EPM), and number of transitions (P<0.05) and time spent in the light compartment (P<0.05) of a light-dark box (LDB). We further investigated the mechanism of action underlying the anxiolytic-like effect of EO and β-caryophyllene by pre-treating animals with antagonists of benzodiazepine (flumazenil) and 5-HT(1A) (NAN-190) receptors prior to evaluation using EPM and LDB. The anxiolytic-like effects of EO were significantly reduced by pre-treatment with NAN-190 (P<0.05) but not flumazenil (P>0.05). The anxiolytic-like effects of β-caryophyllene were not blocked by either NAN-190 or flumazenil (P>0.05). In conclusion, these results suggest that the essential oil derived from S. odoratissima produces an anxiolytic-like effect without altering motor performance and that this effect is mediated by 5-HT(1A) but not via benzodiazepine receptors. In addition, the major component, β-caryophyllene, also has an anxiolytic-like effect that may contribute to the effects of EO, but this effect does not seem to be mediated via 5-HT(1A) or benzodiazepine receptors. 相似文献