scholarly journals Presence of Mycobacterium avium Subspecies paratuberculosis Monitored Over Varying Temporal and Spatial Scales in River Catchments: Persistent Routes for Human Exposure

2019 ◽  
Vol 7 (5) ◽  
pp. 136 ◽  
Author(s):  
Hollian Richardson ◽  
Glenn Rhodes ◽  
Peter Henrys ◽  
Luigi Sedda ◽  
Andrew J. Weightman ◽  
...  
Keyword(s):  
Mycobacterium Avium ◽  
Human Exposure ◽  
Infected Animal ◽  
Wastewater Treatment Plants ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Spatial Scales ◽  
Adequate Representation ◽  
Temporal And Spatial ◽  
First Time ◽  
River Catchments

Mycobacterium avium subspecies paratuberculosis (Map) was monitored by quantitative PCR over a range of temporal and spatial scales in the River Tywi catchment. This study shows the persistence of Map over a 10-year period with little change, which correlates with the recognised levels of Johne’s disease in British herds over that period (aim 1). Map was quantified within the river at up to 108 cell equivalents L−1 and was shown to be consistently present when monitored over finer timescales (aim 4). Small wastewater treatment plants where the ingress of human-associated Map might be expected had no significant effect (aim 2). Map was found for the first time to be located in natural river foams providing another route for spread via aerosols (aim 5). This study provides evidence for the environmental continuum of Map from the grazing infected animal via rain driven runoff through field drains and streams into main rivers; with detection at a high frequency throughout the year. Should Map need to be monitored in the future, we recommend that weekly or monthly sampling from a fixed location on a river will capture an adequate representation of the flow dynamics of Map in a catchment (aim 3). The human exposure to Map during this process and its impact on human health remains unquantified.

scholarly journals Mycobacterium avium Subspecies paratuberculosis: Human Exposure through Environmental and Domestic Aerosols

Pathogens ◽  
2014 ◽  
Vol 3 (3) ◽  
pp. 577-595 ◽  
Author(s):  
Glenn Rhodes ◽  
Hollian Richardson ◽  
John Hermon-Taylor ◽  
Andrew Weightman ◽  
Andrew Higham ◽  
...  
Keyword(s):  
Mycobacterium Avium ◽  
Human Exposure ◽  
Mycobacterium Avium Subspecies Paratuberculosis

scholarly journals Microphytoplankton variations during coral spawning at Los Roques, Southern Caribbean

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1747
Author(s):  
Francoise Cavada-Blanco ◽  
Ainhoa L. Zubillaga ◽  
Carolina Bastidas
Keyword(s):  
Primary Productivity ◽  
Spatial Scales ◽  
Anthropogenic Sources ◽  
Southern Caribbean ◽  
Mineralization Of Organic Matter ◽  
Coral Spawning ◽  
Temporal And Spatial ◽  
Benthic Pelagic Coupling ◽  
Trophic Webs ◽  
First Time

Phytoplankton drives primary productivity in marine pelagic systems. This is also true for the oligotrophic waters in coral reefs, where natural and anthropogenic sources of nutrients can alter pelagic trophic webs. In this study, microphytoplankton assemblages were characterized for the first time in relation to expected coral spawning dates in the Caribbean. A hierarchical experimental design was used to examine these assemblages in Los Roques archipelago, Venezuela, at various temporal and spatial scales for spawning events in both 2007 and 2008. At four reefs, superficial water samples were taken daily for 9 days after the full moon of August, including days before, during and after the expected days of coral spawning. Microphytoplankton assemblages comprised 100 microalgae taxa at up to 50 cells per mL (mean ± 8 SD) and showed temporal and spatial variations related to the coral spawning only in 2007. However, chlorophyllaconcentrations increased during and after the spawning events in both years, and this was better matched with analyses of higher taxonomical groups (diatoms, cyanophytes and dinoflagellates), that also varied in relation to spawning times in 2007 and 2008, but asynchronously among reefs. Heterotrophic and mixotrophic dinoflagellates increased in abundance, correlating with a decrease of the diatomCerataulina pelagicaand an increase of the diatomRhizosolenia imbricata. These variations occurred during and after the coral spawning event for some reefs in 2007. For the first time, a fresh-water cyanobacteria species ofAnabaenawas ephemerally found (only 3 days) in the archipelago, at reefs closest to human settlements. Variability among reefs in relation to spawning times indicated that reef-specific processes such as water residence time, re-mineralization rates, and benthic-pelagic coupling can be relevant to the observed patterns. These results suggest an important role of microheterotrophic grazers in re-mineralization of organic matter in coral reef waters and highlight the importance of assessing compositional changes of larger size fractions of the phytoplankton when evaluating primary productivity and nutrient fluxes.

scholarly journals HERV-W and Mycobacterium avium subspecies paratuberculosis Are at Play in Pediatric Patients at Onset of Type 1 Diabetes

Pathogens ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1135
Author(s):  
Marta Noli ◽  
Gianfranco Meloni ◽  
Pietro Manca ◽  
Davide Cossu ◽  
Mario Palermo ◽  
...  
Keyword(s):  
Mycobacterium Avium ◽  
Pediatric Patients ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Humoral Response ◽  
High Serum ◽  
Healthy Population ◽  
Sardinian Population ◽  
Etiological Agents ◽  
Transcriptional Reactivation ◽  
First Time

The etiology of T1D remains unknown, although a variety of etiological agents have been proposed as potential candidates to trigger autoimmunity in susceptible individuals. Emerging evidence has indicated that endogenous human retrovirus (HERV) may play a role in the disease etiopathogenesis; although several epigenetic mechanisms keep most HERVs silenced, environmental stimuli such as infections may contribute to the transcriptional reactivation of HERV-Wand thus promote pathological conditions. Previous studies have indicated that also Mycobacterium avium subspecies paratuberculosis (MAP) could be a potential risk factor for T1D, particularly in the Sardinian population. In the present study, the humoral response against HERV-W envelope and MAP-derived peptides was analyzed to investigate their potential role in T1D etiopathogenesis, in a Sardinian population at T1D onset (n = 26), T1D (45) and an age-matched healthy population (n = 45). For the first time, a high serum-prevalence of anti-Map and anti-HERV-W Abs was observed in pediatric patients at onset of T1D compared to T1D patients and healthy controls. Our results support the hypothesis that external infections and internal reactivations are involved in the etiology of T1D, and that HERV-W activation may be induced by infectious agents such as MAP.

Larval Feeding: Mechanisms, Rates, and Performance in Nature

2018 ◽  
Keyword(s):  
Marine Invertebrates ◽  
Spatial Scales ◽  
Size Spectrum ◽  
Larval Feeding ◽  
Natural Habitats ◽  
Feeding Mechanism ◽  
Temporal And Spatial ◽  
And Performance ◽  
Bioenergetics Models ◽  
Many Particles

Larvae of many marine invertebrates must capture and ingest particulate food in order to develop to metamorphosis. These larvae use only a few physical processes to capture particles, but implement these processes using diverse morphologies and behaviors. Detailed understanding of larval feeding mechanism permits investigators to make predictions about feeding performance, including the size spectrum of particles larvae can capture and the rates at which they can capture them. In nature, larvae are immersed in complex mixtures of edible particles of varying size, density, flavor, and nutritional quality, as well as many particles that are too large to ingest. Concentrations of all of these components vary on fine temporal and spatial scales. Mechanistic models linking larval feeding mechanism to performance can be combined with data on food availability in nature and integrated into broader bioenergetics models to yield increased understanding of the biology of larvae in complex natural habitats.

Humans and the Environment

2013 ◽  
Keyword(s):  
Spatial Scales ◽  
Empirical Studies ◽  
Human Action ◽  
Cultural Practice ◽  
Environmental Archaeology ◽  
Archaeological Data ◽  
Temporal And Spatial ◽  
Global And Local ◽  
The Relationship ◽  
The Way

The environment has always been a central concept for archaeologists and, although it has been conceived in many ways, its role in archaeological explanation has fluctuated from a mere backdrop to human action, to a primary factor in the understanding of society and social change. Archaeology also has a unique position as its base of interest places it temporally between geological and ethnographic timescales, spatially between global and local dimensions, and epistemologically between empirical studies of environmental change and more heuristic studies of cultural practice. Drawing on data from across the globe at a variety of temporal and spatial scales, this volume resituates the way in which archaeologists use and apply the concept of the environment. Each chapter critically explores the potential for archaeological data and practice to contribute to modern environmental issues, including problems of climate change and environmental degradation. Overall the volume covers four basic themes: archaeological approaches to the way in which both scientists and locals conceive of the relationship between humans and their environment, applied environmental archaeology, the archaeology of disaster, and new interdisciplinary directions.The volume will be of interest to students and established archaeologists, as well as practitioners from a range of applied disciplines.

scholarly journals 8-Day and Daily Maximum and Minimum Air Temperature Estimation via Machine Learning Method on a Climate Zone to Global Scale

2021 ◽  
Vol 13 (12) ◽  
pp. 2355
Author(s):  
Linglin Zeng ◽  
Yuchao Hu ◽  
Rui Wang ◽  
Xiang Zhang ◽  
Guozhang Peng ◽  
...  
Keyword(s):  
Spatial Scale ◽  
Air Temperature ◽  
Spatial Scales ◽  
Model Performance ◽  
Global Scale ◽  
Scale Model ◽  
Validation Dataset ◽  
Daily Maximum ◽  
Climate Zone ◽  
Temporal And Spatial

Air temperature (Ta) is a required input in a wide range of applications, e.g., agriculture. Land Surface Temperature (LST) products from Moderate Resolution Imaging Spectroradiometer (MODIS) are widely used to estimate Ta. Previous studies of these products in Ta estimation, however, were generally applied in small areas and with a small number of meteorological stations. This study designed both temporal and spatial experiments to estimate 8-day and daily maximum and minimum Ta (Tmax and Tmin) on three spatial scales: climate zone, continental and global scales from 2009 to 2018, using the Random Forest (RF) method based on MODIS LST products and other auxiliary data. Factors contributing to the relation between LST and Ta were determined based on physical models and equations. Temporal and spatial experiments were defined by the rules of dividing the training and validation datasets for the RF method, in which the stations selected in the training dataset were all included or not in the validation dataset. The RF model was first trained and validated on each spatial scale, respectively. On a global scale, model accuracy with a determination coefficient (R2) > 0.96 and root mean square error (RMSE) < 1.96 °C and R2 > 0.95 and RMSE < 2.55 °C was achieved for 8-day and daily Ta estimations, respectively, in both temporal and spatial experiments. Then the model was trained and cross-validated on each spatial scale. The results showed that the data size and station distribution of the study area were the main factors influencing the model performance at different spatial scales. Finally, the spatial patterns of the model performance and variable importance were analyzed. Both daytime and nighttime LST had a significant contribution in the 8-day Tmax estimation on all the three spatial scales; while their contribution in daily Tmax estimation varied over different continents or climate zones. This study was expected to improve our understanding of Ta estimation in terms of accuracy variations and influencing variables on different spatial and temporal scales. The future work mainly includes identifying underlying mechanisms of estimation errors and the uncertainty sources of Ta estimation from a local to a global scale.

scholarly journals Secondary Effects of Hypochlorite Treatment on the Emerging Pollutant Candesartan: The Formation of Degradation Byproducts and Their Toxicological Profiles

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3422
Author(s):  
Giovanni Luongo ◽  
Lorenzo Saviano ◽  
Giovanni Libralato ◽  
Marco Guida ◽  
Antonietta Siciliano ◽  
...  
Keyword(s):  
Wastewater Treatment Plants ◽  
Parent Compound ◽  
Antihypertensive Agents ◽  
Parent Drug ◽  
Degradation Pathway ◽  
Hplc Method ◽  
Chlorination Process ◽  
Emerging Pollutant ◽  
Ecotoxicity Tests ◽  
First Time

In recent years, many studies have reported the frequent detection of antihypertensive agents such as sartans (olmesartan, valsartan, irbesartan and candesartan) in the influents and effluents of wastewater treatment plants (WWTPs) and in the superficial waters of rivers and lakes in both Europe and North America. In this paper, the degradation pathway for candesartan (CAN) was investigated by simulating the chlorination process that is normally used to reduce microbial contamination in a WWTP. Twelve isolated degradation byproducts (DPs), four of which were isolated for the first time, were separated on a C-18 column by employing a gradient HPLC method, and their structures were identified by combining nuclear magnetic resonance and mass spectrometry and comparing the results with commercial standards. On the basis of these results, a mechanism of formation starting from the parent drug is proposed. The ecotoxicity of CAN and its DPs was studied by conducting a battery of ecotoxicity tests; bioassays were performed using Aliivibrio fischeri (bacterium), Daphnia magna (planktonic crustacean) and Raphidocelis subcapitata (alga). The ecotoxicity results shed new light on the increased toxicity of DPs compared with the parent compound.

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