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النتائج 991 - 1000 من 3,208
Indoor and outdoor microbial aerosols at the holy mosque: A case study النص الكامل
2015
Mashat, Bassam
The aim of this study was to evaluate bacterial and fungal aerosol concentrations at the holy mosque (Al-Masjid Al-Haram). Air samples were collected from different locations inside and outside the holy mosque, during the month of Ramadan-2011 (the fasting month), using a portable Air-port MD8 gelatin filter sampler. Trypticase soya agar and Capek's dox agar media were used to count bacteria and fungi, respectively. The mean concentrations of airborne bacteria and fungi ranged between 105–106 colony forming unit per cubic meter of air (CFU/m3) outside, and ∼102–105 CFU/m3 inside locations. The highest outside bacterial concentrations 106 CFU/m3 were found at the Al Umra, Al Fatah and eastern plazas, and the highest inside fungal concentrations ∼105 CFU/m3 were found at the courtyard, expansion of 1st floor, and roof. Significant differences (P < 0.05) were found between bacterial and fungal concentrations inside and outside sampling locations, higher concentrations shifted towards to outside locations. Significant differences were also found between the bacterial and fungal concentrations inside–unclosed and semi-closed (P < 0.05) with inside-closed locations. Gram-positive bacteria, Bacillus and Micrococcus, and fungi, Aspergillus niger were the dominant microbial aerosol genera. The obtained data is considered a step to make up the gap about airborne microbial contamination inside the holy mosque, and microbial air quality should be studied along over the year at the holy mosque in the future.
اظهر المزيد [+] اقل [-]Carriage of Clostridium perfringens by benthic crabs in a sewage-polluted estuary النص الكامل
2015
La Sala, Luciano F. | Redondo, Leandro M. | Díaz Carrasco, Juan M. | Pereyra, Ana María | Farber, Marisa | Jost, Helen | Fernández-Miyakawa, Mariano E.
The Estuary of Bahía Blanca (EBB), Argentina, is an important wetland under intense sewage pollution. We investigated the occurrence of Clostridium perfringens (CP) in populations of two benthic crabs (Neohelice granulata and Cyrtograpsus angulatus) and in sediment from the EBB. CP was found in 49.1% of the crabs and all of the isolates were identified as type A. The alpha (cpa) and enterotoxin (cpe) encoding genes were identified. Genetic analyses identified 13 novel sequence types, and found no clustering among isolates, suggesting that CP is not part of the crabs’ commensal flora. CP carriage was 51 times more likely in crabs from the area nearest sewage outfalls compared with crabs from a reference site. Our in vitro experiments suggest that the carriage of CP in crabs is transient. The use of these benthic crabs as monitoring organisms of sewage pollution in coastal habitats is proposed.
اظهر المزيد [+] اقل [-]Intercomparison between NIOSH, IMPROVE_A, and EUSAAR_2 protocols: Finding an optimal thermal–optical protocol for Philippines OC/EC samples النص الكامل
2015
Bautista, Angel T. | Pabroa, Preciosa Corazon B. | Santos, Flora L. | Quirit, Leni L. | Asis, Joannes Luke B. | Dy, Marie Alexandra K. | Martinez, Jason Patrick G.
Thermal–optical analysis is one of the most widely–recognized methods for measuring organic carbon (OC) and elemental carbon (EC) in atmospheric particulates. Up to date however, there is no standard protocol of analysis and different protocols give varying OC/EC apportionments. This study aims to find an optimal thermal–optical analysis protocol for Philippine OC/EC samples by comparing three widely–used protocols: NIOSH, IMPROVE_A and EUSAAR_2. Philippines is particularly interesting because it has one of the highest EC concentration and lowest OC/EC ratio in the region. In terms of total OC and EC quantification, NIOSH and IMPROVE_A show negative and positive EC bias, respectively – NIOSH exhibits premature EC evolution in the OC4 pure He phase, while IMPROVE_A OC4 temperature step (580 °C) is not sufficiently high, causing some OC to be carried over to He/O2 phase to be measured mainly as EC2. EUSAAR_2 minimizes both effects and may be most accurate in this aspect. However, IMPROVE_A is the only method that is capable of properly resolving individual OC and Philippines’s particularly abundant EC fractions owing to the protocol’s variable step durations. Concurrently, IMPROVE_A and EUSAAR_2 yield lowest pyrolized carbon (PC) formation for urban and rural site, respectively. Minimal PC formation is desired to minimize errors associated with its correction. Finally, transmittance laser correction is preferred over reflectance as it is capable of accounting for char formed within filter. The study thus recommends a modified IMPROVE_A, with increased OC4 temperature step (650 °C, adopted from EUSAAR_2) and transmittance laser correction, as optimal. This protocol is expected to give proper OC and EC evolution, fractionation, and measurement with minimized PC formation and proper correction, leading to more accurate results. Preliminary testing shows that recommended protocol meets those expectations. Application to larger number and wider variety of samples is needed to more properly assert these findings.
اظهر المزيد [+] اقل [-]Dynamite fishing in Tanzania النص الكامل
2015
Slade, Lorna M. | Kalangahe, Baraka
Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private–public partnerships for patrol and protection.
اظهر المزيد [+] اقل [-]Pollution exposure on marine protected areas: A global assessment النص الكامل
2015
Partelow, Stefan | von Wehrden, Henrik | Horn, Olga
Marine protected areas (MPAs) face many challenges in their aim to effectively conserve marine ecosystems. In this study we analyze the extent of pollution exposure on the global fleet of MPAs. This includes indicators for current and future pollution and the implications for regionally clustered groups of MPAs with similar biophysical characteristics. To cluster MPAs into characteristic signature groups, their bathymetry, baseline biodiversity, distance from shore, mean sea surface temperature and mean sea surface salinity were used. We assess the extent at which each signature group is facing exposure from multiple pollution types. MPA groups experience similar pollution exposure on a regional level. We highlight how the challenges that MPAs face can be addressed through governance at the appropriate scale and design considerations for integrated terrestrial and marine management approaches within regional level networks. Furthermore, we present diagnostic social-ecological indicators for addressing the challenges facing unsuccessful MPAs with practical applications.
اظهر المزيد [+] اقل [-]Accurate assessment of the impact of salmon farming on benthic sediment enrichment using foraminiferal metabarcoding النص الكامل
2015
Pochon, X. | Wood, S.A. | Keeley, N.B. | Lejzerowicz, F. | Esling, P. | Drew, J. | Pawlowski, J.
Assessing the environmental impact of salmon farms on benthic systems is traditionally undertaken using biotic indices derived from microscopic analyses of macrobenthic infaunal (MI) communities. In this study, we tested the applicability of using foraminiferal-specific high-throughput sequencing (HTS) metabarcoding for monitoring these habitats. Sediment samples and physico-chemical data were collected along an enrichment gradient radiating out from three Chinook salmon (Oncorhynchus tshawytscha) farms in New Zealand. HTS of environmental DNA and RNA (eDNA/eRNA) resulted in 1,875,300 sequences that clustered into 349 Operational Taxonomic Units. Strong correlations were observed among various biotic indices calculated from MI data and normalized fourth-root transformed HTS data. Correlations were stronger using eRNA compared to eDNA data. Quantile regression spline analyses identified 12 key foraminiferal taxa that have potential to be used as bioindicator species. This study demonstrates the huge potential for using this method for biomonitoring of fish-farming and other marine industrial activities.
اظهر المزيد [+] اقل [-]Particulate matter in ambient air and its association with alterations in lung functions and respiratory health problems among outdoor exercisers in National Capital Region, India النص الكامل
2015
Kesavachandran, Chandrasekharan Nair | Kamal, Ritul | Bihari, Vipin | Pathak, Manoj Kumar | Singh, Amarnath
Regular exercise improves physiological processes and yields positive health outcomes. However, it is relatively less known that exposure to air pollution during outdoor exercises may actually exacerbate several health problems. The present cross–sectional study was undertaken to assess the particulate matter (PM) in the ambient air and its association with lung functions, pulse rate and respiratory problems among 378 outdoor exercisers in the National Capital Region (NCR), India. Lung functions were measured using a Spirometer (PIKO–1, PIKO–6) and respiratory problems were recorded through a questionnaire–based survey. Concentrations of particulate matter smaller than 2.5 and 1 microns were monitored at 10 locations across the study area using an online automated ambient air monitoring instrument–HAZ–DUST (EPAM–5000). Decline in Forced Expiratory Volume in 1 sec–FEV1 (p<0.001) and Peak Expiratory Flow Rate–PEFR (p<0.001) was observed among the outdoor exercisers compared to the Indian reference values. Ambient air monitoring showed higher PM2.5 concentrations at all the study locations compared to the recommended permissible levels for residential areas in India. Risk of FEV1 (%) predicted cases with <80% showed an increase from 2.32% to 8.69% among the exercisers with respect to PM1 concentration from lower to higher limit at the study locations. Similarly, PEFR showed an increased risk of predicted cases <80% from 0.78% to 2.91% among outside exercisers for lower to higher limit of PM1 concentration. Cases with FEV1 predicted <80% increased from 2.56% to 13.98% and for PEFR from 0.96% to 5.24% among outdoor exercisers for the corresponding lower to higher limits of PM2.5 concentrations. The study demonstrates that outdoor exercisers in locations with high PM concentrations are at a risk of lung function impairment. These impairments are due to deposition of PM in the smaller and larger airways.
اظهر المزيد [+] اقل [-]Substrates specialization in lipid compounds and hydrocarbons of Marinobacter genus. النص الكامل
2015
Bonin, Patricia | Vieira, Christophe | Grimaud, Régis | Militon, Cécile | Cuny, Philippe | Lima, Oscar | Guasco, Sophie | Brussaard, Corina P D | Michotey, Valerie
Substrates specialization in lipid compounds and hydrocarbons of Marinobacter genus. النص الكامل
2015
Bonin, Patricia | Vieira, Christophe | Grimaud, Régis | Militon, Cécile | Cuny, Philippe | Lima, Oscar | Guasco, Sophie | Brussaard, Corina P D | Michotey, Valerie
International audience | The impact of petroleum contamination and of burrowing macrofauna on abundances of Marinobacter and denitrifiers was tested in marine sediment mesocoms after 3 months incubation. Quantification of this genus by qPCR with a new primer set showed that the main factor favoring Marinobacter abundance was hydrocarbon amendment followed by macrofauna presence. In parallel, proportion of nosZ-harboring bacteria increased in the presence of marcrofauna. Quantitative finding were explained by physiological data from a set of 34 strains and by genomic analysis of 16 genomes spanning 15 different Marinobacter-validated species (Marinobacter hydrocarbonoclasticus, Marinobacter daeopensis, Marinobacter santoriniensis, Marinobacter pelagius, Marinobacter flavimaris, Marinobacter adhaerens, Marinobacter xestospongiae, Marinobacter algicola, Marinobacter vinifirmus, Marinobacter maritimus, Marinobacter psychrophilus, Marinobacter lipoliticus, Marinobacter manganoxydans, Marinobacter excellens, Marinobacter nanhaiticus) and 4 potential novel ones. Among the 105 organic electron donors tested in physiological analysis, Marinobacter pattern appeared narrow for almost all kinds of organic compounds except lipid ones. Strains of this set could oxidize a very large spectrum of lipids belonging to glycerolipids, branched, fatty acyls, and aromatic hydrocarbon classes. Physiological data were comforted by genomic analysis, and genes of alkane 1-monooxygenase, haloalkane dehalogenase, and flavin-binding monooxygenase were detected in most genomes. Denitrification was assessed for several strains belonging to M. hydrocarbonoclasticus, M. vinifirmus, Marinobacter maritinus, and M. pelagius species indicating the possibility to use nitrate as alternative electron acceptor. Higher occurrence of Marinobacter in the presence of petroleum appeared to be the result of a broader physiological trait allowing this genus to use lipids including hydrocarbon as principal electron donors.
اظهر المزيد [+] اقل [-]Substrates specialization in lipid compounds and hydrocarbons of Marinobacter genus النص الكامل
2015
Bonin, Patricia | Vieira, Christophe | Grimaud, Régis | Militon, Cécile | Cuny, Philippe | Lima, Oscar | Guasco, Sophie | Brussaard, Corina P. D. | Michotey, Valérie
The impact of petroleum contamination and of burrowing macrofauna on abundances of Marinobacter and denitrifiers was tested in marine sediment mesocoms after 3 months incubation. Quantification of this genus by qPCR with a new primer set showed that the main factor favoring Marinobacter abundance was hydrocarbon amendment followed by macrofauna presence. In parallel, proportion of nosZ-harboring bacteria increased in the presence of marcrofauna. Quantitative finding were explained by physiological data from a set of 34 strains and by genomic analysis of 16 genomes spanning 15 different Marinobacter-validated species (Marinobacter hydrocarbonoclasticus, Marinobacter daeopensis, Marinobacter santoriniensis, Marinobacter pelagius, Marinobacter flavimaris, Marinobacter adhaerens, Marinobacter xestospongiae, Marinobacter algicola, Marinobacter vinifirmus, Marinobacter maritimus, Marinobacter psychrophilus, Marinobacter lipoliticus, Marinobacter manganoxydans, Marinobacter excellens, Marinobacter nanhaiticus) and 4 potential novel ones. Among the 105 organic electron donors tested in physiological analysis, Marinobacter pattern appeared narrow for almost all kinds of organic compounds except lipid ones. Strains of this set could oxidize a very large spectrum of lipids belonging to glycerolipids, branched, fatty acyls, and aromatic hydrocarbon classes. Physiological data were comforted by genomic analysis, and genes of alkane 1-monooxygenase, haloalkane dehalogenase, and flavin-binding monooxygenase were detected in most genomes. Denitrification was assessed for several strains belonging to M. hydrocarbonoclasticus, M. vinifirmus, Marinobacter maritinus, and M. pelagius species indicating the possibility to use nitrate as alternative electron acceptor. Higher occurrence of Marinobacter in the presence of petroleum appeared to be the result of a broader physiological trait allowing this genus to use lipids including hydrocarbon as principal electron donors.
اظهر المزيد [+] اقل [-]Substrates specialization in lipid compounds and hydrocarbons of Marinobacter genus. النص الكامل
2015
Bonin, Patricia | Vieira, Christophe | Grimaud, Régis | Militon, Cécile | Cuny, Philippe | Lima, Oscar | Guasco, Sophie | Brussaard, Corina P D | Michotey, Valerie | Institut méditerranéen d'océanologie (MIO) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) | MEB ; Institut méditerranéen d'océanologie (MIO) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Ecologie Moléculaire, IBEAS, EA 3525 ; Université de Pau et des Pays de l'Adour (UPPA) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Royal Netherlands Institute for Sea Research (NIOZ)
International audience | The impact of petroleum contamination and of burrowing macrofauna on abundances of Marinobacter and denitrifiers was tested in marine sediment mesocoms after 3 months incubation. Quantification of this genus by qPCR with a new primer set showed that the main factor favoring Marinobacter abundance was hydrocarbon amendment followed by macrofauna presence. In parallel, proportion of nosZ-harboring bacteria increased in the presence of marcrofauna. Quantitative finding were explained by physiological data from a set of 34 strains and by genomic analysis of 16 genomes spanning 15 different Marinobacter-validated species (Marinobacter hydrocarbonoclasticus, Marinobacter daeopensis, Marinobacter santoriniensis, Marinobacter pelagius, Marinobacter flavimaris, Marinobacter adhaerens, Marinobacter xestospongiae, Marinobacter algicola, Marinobacter vinifirmus, Marinobacter maritimus, Marinobacter psychrophilus, Marinobacter lipoliticus, Marinobacter manganoxydans, Marinobacter excellens, Marinobacter nanhaiticus) and 4 potential novel ones. Among the 105 organic electron donors tested in physiological analysis, Marinobacter pattern appeared narrow for almost all kinds of organic compounds except lipid ones. Strains of this set could oxidize a very large spectrum of lipids belonging to glycerolipids, branched, fatty acyls, and aromatic hydrocarbon classes. Physiological data were comforted by genomic analysis, and genes of alkane 1-monooxygenase, haloalkane dehalogenase, and flavin-binding monooxygenase were detected in most genomes. Denitrification was assessed for several strains belonging to M. hydrocarbonoclasticus, M. vinifirmus, Marinobacter maritinus, and M. pelagius species indicating the possibility to use nitrate as alternative electron acceptor. Higher occurrence of Marinobacter in the presence of petroleum appeared to be the result of a broader physiological trait allowing this genus to use lipids including hydrocarbon as principal electron donors.
اظهر المزيد [+] اقل [-]Debris ingestion by the Antillean Manatee (Trichechus manatus manatus) النص الكامل
2015
Attademo, Fernanda Loffler Niemeyer | Balensiefer, Deisi Cristiane | Freire, Augusto Carlos da Bôaviagem | de Sousa, Glaucia Pereira | da Cunha, Fábio Adonis Gouveia Carneiro | Luna, Fábia de Oliveira
The Antillean manatee inhabits coastal regions of North and Northeastern Brazil and currently is considered an endangered species in the country. Aiming to gather information for the development of public policies focusing on the conservation of manatees, the National Center for Research and Conservation of Aquatic Mammals of the Chico Mendes Institute for Biodiversity has been rescuing, rehabilitating and releasing these mammals since the 1980s. Over the last 36years, 40 manatees were released by the CMA/ICMBio and four of them were rescued again due to debris ingestion. Two of these manatees died and the other two were taken back into captivity for a new rehabilitation process. The four mammals had confirmed diagnosis of plastic debris ingestion. These findings demonstrate that the environment where the manatees live after being released had a significant amount of garbage which may hinder the success of the species conservation in Brazil.
اظهر المزيد [+] اقل [-]Metal Pollution in Coastal Sediments النص الكامل
2015
Qian, Yu | Zhang, Weiguo | Yu, Lizhong | Feng, Huan
Coastal sediment is a vital habitat for aquatic and marine life in coastal ecosystem. However, urbanization and economic development in coastal areas have resulted in environmental problems globally. Due to coastal development such as new industrial facilities and commercial port expansion, anthropogenic metals are introduced to the adjacent areas. Therefore, metal pollution in coastal areas is one of the focused environmental concerns. Sediment quality in coastal zone reflects the long-term environmental status because it keeps a record of the development in the area. In this review paper, sediment metal concentrations in 52 selected sites worldwide are summarized for evaluation of the coastal environmental quality. The results from this study can be applied to science-based policy formulation and ecological restoration/rehabilitation practices in an integrated coastal zone environmental management.
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