587 research outputs found

    Effect of biochars pyrolyzed in N2 and CO2, and feedstock on microbial community in metal(loid)s contaminated soils

    Get PDF
    Little is known about the effects of applying amendments on soil for immobilizing metal(loid)s on the soil microbial community. Alterations in the microbial community were examined after incubation of treated contaminated soils. One soil was contaminated with Pb and As, a second soil with Cd and Zn. Red pepper stalk (RPS) and biochars produced from RPS in either N2 atmosphere (RPSN) or CO2 atmosphere (RPSC) were applied at a rate of 2.5% to the two soils and incubated for 30 days. Bacterial communities of control and treated soils were characterized by sequencing 16S rRNA genes using the Illumina MiSeq sequencing. In both soils, bacterial richness increased in the amended soils, though somewhat differently between the treatments. Evenness values decreased significantly, and the final overall diversities were reduced. The neutralization of pH, reduced available concentrations of Pb or Cd, and supplementation of available carbon and surface area could be possible factors affecting the community changes. Biochar amendments caused the soil bacterial communities to become more similar than those in the not amended soils. The bacterial community structures at the phylum and genus levels showed that amendment addition might restore the normal bacterial community of soils, and cause soil bacterial communities in contaminated soils to normalize and stabilize

    Proceedings of The First Current Topic in Infectious Diseases: Consensus Meeting on Conjugate Vaccines of the Center of Infection

    Get PDF
    Titles include: 1. Invasive Haemophilus Influenzae b Disease: Overview and Disease Burden in Hong Kong (YL LAU) ; 2. Overview and Disease Burden of Haemophilus Influenzae Type b in China (YH YANG) ; 3. Factors to Consider in the Routine Use of Hib in Hong Kong (THF TSANG) ; 4. Burden of Pneumococcal Disease in Hong Kong (CB CHOW) ; 5. Overview and Disease Burden of Streptococcus Pneumoniae in China (YH YANG) ; 6. Resistance in Pediatric Isolates of Pneumococci. Results from a Territorywide Carriage Study (SSS CHIU) ; 7. Serotype Distribution of Invasive and Noninvasive Strains of Pneumococci in Hong Kong (PL HO) ; 8. Overview of Conjugate Pneumococcal Vaccine: Serotype Coverage, Efficacy and Status of Usage in other Countries (SSY WONG)Conference Theme: The First Current Topic in Infectious Diseasespublished_or_final_versio

    Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species

    Get PDF
    Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu–Glu–Leu–Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu–Glu–Leu–Glu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species. © 2015, MDPI AG. All rights Reserved.published_or_final_versio

    Intrusion detection routers: Design, implementation and evaluation using an experimental testbed

    Get PDF
    In this paper, we present the design, the implementation details, and the evaluation results of an intrusion detection and defense system for distributed denial-of-service (DDoS) attack. The evaluation is conducted using an experimental testbed. The system, known as intrusion detection router (IDR), is deployed on network routers to perform online detection on any DDoS attack event, and then react with defense mechanisms to mitigate the attack. The testbed is built up by a cluster of sufficient number of Linux machines to mimic a portion of the Internet. Using the testbed, we conduct real experiments to evaluate the IDR system and demonstrate that IDR is effective in protecting the network from various DDoS attacks. © 2006 IEEE.published_or_final_versio

    Seizures, cysticercosis and rural-to-urban migration: the PERU MIGRANT study.

    Get PDF
    OBJECTIVES: To examine the prevalence of seizures, epilepsy and seropositivity to cysticercosis in rural villagers (cysticercosis-endemic setting), rural-to-urban migrants into a non-endemic urban shanty town and urban inhabitants of the same non-endemic shanty town. METHODS: Three Peruvian populations (n = 985) originally recruited into a study about chronic diseases and migration were studied. These groups included rural inhabitants from an endemic region (n = 200), long-term rural-to-urban migrants (n = 589) and individuals living in the same urban setting (n = 196). Seizure disorders were detected by a survey, and a neurologist examined positive respondents. Serum samples from 981/985 individuals were processed for cysticercosis antibodies on immunoblot. RESULTS: Epilepsy prevalence (per 1000 people) was 15.3 in the urban group, 35.6 in migrants and 25 in rural inhabitants. A gradient in cysticercosis antibody seroprevalence was observed: urban 2%, migrant 13.5% and rural group 18% (P < 0.05). A similarly increasing pattern of higher seroprevalence was observed among migrants by age at migration. In rural villagers, there was strong evidence of an association between positive serology and having seizures (P = 0.011) but such an association was not observed in long-term migrants or in urban residents. In the entire study population, compared with seronegative participants, those with strong antibody reactions (≥ 4 antibody bands) were more likely to have epilepsy (P < 0.001). CONCLUSIONS: It is not only international migration that affects cysticercosis endemicity; internal migration can also affect patterns of endemicity within an endemic country. The neurological consequences of cysticercosis infection likely outlast the antibody response for years after rural-to-urban migration
    corecore