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1.
Nat Ecol Evol ; 7(3): 405-413, 2023 03.
Article in English | MEDLINE | ID: mdl-36702858

ABSTRACT

High-elevation ecosystems are among the few ecosystems worldwide that are not yet heavily invaded by non-native plants. This is expected to change as species expand their range limits upwards to fill their climatic niches and respond to ongoing anthropogenic disturbances. Yet, whether and how quickly these changes are happening has only been assessed in a few isolated cases. Starting in 2007, we conducted repeated surveys of non-native plant distributions along mountain roads in 11 regions from 5 continents. We show that over a 5- to 10-year period, the number of non-native species increased on average by approximately 16% per decade across regions. The direction and magnitude of upper range limit shifts depended on elevation across all regions. Supported by a null-model approach accounting for range changes expected by chance alone, we found greater than expected upward shifts at lower/mid elevations in at least seven regions. After accounting for elevation dependence, significant average upward shifts were detected in a further three regions (revealing evidence for upward shifts in 10 of 11 regions). Together, our results show that mountain environments are becoming increasingly exposed to biological invasions, emphasizing the need to monitor and prevent potential biosecurity issues emerging in high-elevation ecosystems.


Subject(s)
Altitude , Ecosystem , Introduced Species , Plants , Plant Dispersal
2.
Microb Ecol ; 85(3): 875-891, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35867139

ABSTRACT

Peatland ecosystems cover only 3% of the world's land area; however, they store one-third of the global soil carbon (C). Microbial communities are the main drivers of C decomposition in peatlands, yet we have limited knowledge of their structure and function. While the microbial communities in the Northern Hemisphere peatlands are well documented, we have limited understanding of microbial community composition and function in the Southern Hemisphere peatlands, especially in Australia. We investigated the vertical stratification of prokaryote and fungal communities from Wellington Plains peatland in the Australian Alps. Within the peatland complex, bog peat was sampled from the intact peatland and dried peat from the degraded peatland along a vertical soil depth gradient (i.e., acrotelm, mesotelm, and catotelm). We analyzed the prokaryote and fungal community structure, predicted functional profiles of prokaryotes using PICRUSt, and assigned soil fungal guilds using FUNGuild. We found that the structure and function of prokaryotes were vertically stratified in the intact bog. Soil carbon, manganese, nitrogen, lead, and sodium content best explained the prokaryote composition. Prokaryote richness was significantly higher in the intact bog acrotelm compared to degraded bog acrotelm. Fungal composition remained similar across the soil depth gradient; however, there was a considerable increase in saprotroph abundance and decrease in endophyte abundance along the vertical soil depth gradient. The abundance of saprotrophs and plant pathogens was two-fold higher in the degraded bog acrotelm. Soil manganese and nitrogen content, electrical conductivity, and water table level (cm) best explained the fungal composition. Our results demonstrate that both fungal and prokaryote communities are shaped by soil abiotic factors and that peatland degradation reduces microbial richness and alters microbial functions. Thus, current and future changes to the environmental conditions in these peatlands may lead to altered microbial community structures and associated functions which may have implications for broader ecosystem function changes in peatlands.


Subject(s)
Ecosystem , Microbiota , Australia , Carbon/metabolism , Manganese , Nitrogen/analysis , Soil/chemistry , Soil Microbiology
3.
Blood Adv ; 6(13): 3861-3869, 2022 07 12.
Article in English | MEDLINE | ID: mdl-35476051

ABSTRACT

Severe chronic neutropenia (SCN), defined as blood neutrophils <0.5 × 109/L for >3 months, is an uncommon hematological condition associated with recurrent and severe bacterial infections. After short-term clinical trials showed the benefits of granulocyte colony-stimulating factor (G-CSF) treatment for SCN, SCNIR (Severe Chronic Neutropenia International Registry) opened to determine the long-term benefits and safety of this treatment. This report summarizes findings from more than 16 000 patient-years of prospective observations for patients with congenital and acquired SCN. We observed that adverse outcomes depend on the underlying etiology. Myelodysplasia (MDS) and acute myeloid leukemia (AML) occur infrequently and largely in patients with congenital neutropenias. Having cyclic or chronic autoimmune/ idiopathic neutropenia portends a favorable prognosis. A few patients with idiopathic neutropenia evolve to develop lymphoid malignancies, but they do not appear to be at increased risk of myeloid malignancies, even with very long-term G-CSF therapy. Progression to systemic autoimmune diseases, bone marrow (BM) failure, aplastic anemia, or nonmyeloid malignancies are not expected consequences of SCN or treatment with G-CSF.


Subject(s)
Granulocyte Colony-Stimulating Factor , Myelodysplastic Syndromes , Neutropenia , Chronic Disease , Granulocyte Colony-Stimulating Factor/therapeutic use , Humans , Myelodysplastic Syndromes/drug therapy , Neutropenia/drug therapy , Prospective Studies
4.
PLoS One ; 11(12): e0164493, 2016.
Article in English | MEDLINE | ID: mdl-27935940

ABSTRACT

Resistance to soybean rust (SBR), caused by Phakopsora pachyrhizi Syd. & Syd., has been identified in many soybean germplasm accessions and is conferred by either dominant or recessive genes that have been mapped to six independent loci (Rpp1 -Rpp6), but No U.S. cultivars are resistant to SBR. The cultivar DT 2000 (PI 635999) has resistance to P. pachyrhizi isolates and field populations from the United States as well as Vietnam. A F6:7 recombinant inbred line (RIL) population derived from Williams 82 × DT 2000 was used to identify genomic regions associated with resistance to SBR in the field in Ha Noi, Vietnam, and in Quincy, Florida, in 2008. Bulked segregant analysis (BSA) was conducted using the soybean single nucleotide polymorphism (SNP) USLP 1.0 panel along with simple sequence repeat (SSR) markers to detect regions of the genome associated with resistance. BSA identified four BARC_SNP markers near the Rpp3 locus on chromosome (Chr.) 6. Genetic analysis identified an additional genomic region around the Rpp4 locus on Chr. 18 that was significantly associated with variation in the area under disease progress curve (AUDPC) values and sporulation in Vietnam. Molecular markers tightly linked to the DT 2000 resistance alleles on Chrs. 6 and 18 will be useful for marker-assisted selection and backcrossing in order to pyramid these genes with other available SBR resistance genes to develop new varieties with enhanced and durable resistance to SBR.


Subject(s)
Chromosomes, Plant/chemistry , Genome, Plant , Glycine max/genetics , Phakopsora pachyrhizi/physiology , Plant Diseases/genetics , Spores, Fungal/physiology , Alleles , Chromosome Mapping , Disease Resistance/genetics , Genetic Loci , Genetic Markers/immunology , Genotype , Microsatellite Repeats/immunology , Phakopsora pachyrhizi/pathogenicity , Plant Diseases/immunology , Plant Diseases/microbiology , Polymorphism, Single Nucleotide , Glycine max/immunology , Glycine max/microbiology , Spores, Fungal/pathogenicity
5.
Environ Sci Process Impacts ; 17(1): 81-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25406684

ABSTRACT

Submerged attached growth bioreactors (SAGBs) were operated at 20 °C for 30 weeks in smart-aerated, partial nitritation ANAMMOX mode and in a timer-controlled, cyclic aeration mode. The smart-aerated SAGBs removed 48-53% of total nitrogen (TN) compared to 45% for SAGBs with timed aeration. Low dissolved oxygen concentrations and cyclic pH patterns in the smart-aerated SAGBs suggested conditions favorable to partial nitritation ANAMMOX and stoichiometrically-derived and numerically modeled estimations attributed 63-68% and 14-44% of TN removal to partial nitritation ANAMMOX in these bioreactors, respectively. Ammonia removals of 36-67% in the smart-aerated SAGBs, with measured oxygen and organic carbon limitations, further suggest partial nitritation ANAMMOX. The smart-aerated SAGBs required substantially less aeration to achieve TN removals similar to SAGBs with timer-controlled aeration. Genomic DNA testing confirmed that the dominant ANAMMOX seed bacteria, received from a treatment plant utilizing the DEMON® sidestream deammonification process, was a Candidatus Brocadia sp. (of the Planctomycetales order). The DNA from these bacteria was also present in the SAGBs at the conclusion of the study providing evidence for attached growth and limited biomass washout.


Subject(s)
Ammonium Compounds/metabolism , Bioreactors/microbiology , Waste Disposal, Fluid/methods , Anaerobiosis , Biodegradation, Environmental
7.
Article in English | MEDLINE | ID: mdl-24109348

ABSTRACT

In the dication of the title salt, C16H21ClN2O(2+)·2C6H2N3O7 (-) [systematic name: 2-{(4-chloro-phen-yl)[2-(di-methyl-aza-nium-yl)eth-oxy]meth-yl}pyridinium bis-(2,4,6-tri-nitro-phenolate), contains a carbinoxaminium dication and two picrate anions, which are held together through inter-molecular N-H⋯O hydrogen bonds. In the dication, the two aromatic rings form a dihedral angle of 80.1 (1)°. In the two independent picrate anions, the nitro groups are twisted from the benzene plane, the largest dihedral angle in each ion being 42.8 (1) and 81.1 (5)°. In the crystal, in addition to the classical N-H⋯O hydrogen bonds, weak C-H⋯O hydrogen bonds and π-π inter-actions between the aromatic rings of the anions [centroid-centroid distances of 3.5768 (15) and 3.7436 (15) Å] help to establish the packing.

8.
Theor Appl Genet ; 121(7): 1253-66, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20559815

ABSTRACT

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pest of soybean worldwide. Host plant resistance is an effective approach to control this pest. Plant introduction PI 567516C has been reported to be highly resistant to multiple-HG types of SCN. The objectives of this study were to identify and map novel quantitative trait loci (QTL) for SCN resistance to six HG types (also known as races 1, 2, 3, 5, 14, and LY1). Mapping was conducted using 250 F(2:3) progeny derived from a Magellan (susceptible) × PI 567516C (resistant) cross. F(6:7) recombinant inbred lines (RILs) developed from the F(2:3) progeny were employed to confirm the putative QTL identified. A total of 927 polymorphic simple sequence repeats (SSR) and single nucleotide polymorphism (SNP) markers were genotyped. Following the genetic linkage analysis, permutation tests and composite interval mapping were performed to identify and map QTL. Four QTL were associated with resistance to either multiple- or single-SCN HG types. Two QTL for resistance to multiple-SCN HG types were mapped to Chromosomes 10 and 18 and have not been reported in other SCN resistance sources. New QTL were confirmed by analysis of 250 F(6:7) RILs from the same population. SSR and SNP markers closely associated with these QTL can be useful for the development of near-isogenic lines for fine-mapping and positional cloning of candidate genes for SCN resistance.


Subject(s)
Glycine max/genetics , Glycine max/parasitology , Quantitative Trait Loci/genetics , Tylenchida/pathogenicity , Animals , Chromosome Mapping , Crosses, Genetic , Female , Genetic Linkage , Genotype , Host-Parasite Interactions/genetics , Minisatellite Repeats/genetics , Phenotype , Plant Diseases/genetics , Plant Diseases/parasitology , Plant Immunity/genetics , Polymorphism, Single Nucleotide
12.
Conn Med ; 73(2): 113-6, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19263745
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