104 research outputs found
Alien Registration- Michaud, Emma (Allagash, Aroostook County)
https://digitalmaine.com/alien_docs/32343/thumbnail.jp
Sediment reworking by marine benthic species from the Gullmar Fjord (Western Sweden): Importance of faunal biovolume
In order to compare and quantify sediment reworking activities by different species/functional groups of macrofauna, a laboratory experiment was carried out with species from the Gullmarsfjord (Western Sweden). Monospecific communities of Amphiura filiformis, Echinocardium cordatum, Scalibregma inflatum and Abra nitida were introduced in experimental mesocosms, with identical densities (795 ind. mâ2), for 10 days. Sediment reworking was studied by quantifying downward and upward movements of fluorescent inert tracers (luminophores). Luminophores with different colour were initially deposited both at the sediment surface and within the sediments. Population biomass and biovolume were also determined. Surface tracers reworking coefficients ranged from 0.6 to 2.2 cm2 yâ1 and 0.9 to 4.1 yâ1, respectively for the biodiffusive-like and non-local transports. Calculated biodiffusive-like coefficient was between 1.0 and 2.3 cm2 yâ1 for the deep tracers. For both tracers, the E. cordatum population presented the highest reworking coefficients. Among the morphological and/or ethological parameters that could determine overall patterns of reworking and differences between species, results have shown a direct relationship between the apparent biodiffusive mixing and the biovolume of the individuals (Db=0.35 â Biovolume). This suggests that the biovolume of macrofauna may allow a rough estimate of the biodiffusive-like reworking intensity of particles deposited on the sediment surface
Use of axial tomography to follow temporal changes of benthic communities in an unstable sedimentary environment (Baie des Ha! Ha!, Saguenay Fjord)
In the upper layer of the sediment column, organic matter recycling is greatly influenced by bioturbation. However, there are many physical changes in the nature of the sediment that may disturb benthic communities and create a biogeochemical imbalance. Following a very heavy rainfall between 26 and 29 July 1996, an intense flash flood in the Saguenay Fjord caused discharges of 6 million cubic metres of sediments into Baie des Ha! Ha!. Unstable sediment deposits located at the top of the delta of the Rivie`re des Ha! Ha! were sporadically exported to the deep basin. After this physical disturbance, meiobenthic and macrobenthic organisms progressively re-colonised the sediment column. To determine the impacts of such sedimentary depositions on benthic fauna, two stations, one at the head and one at the mouth of the Baie des Ha! Ha!, have been monitored since 1996. During this survey, we developed a new method for the quantification of biogenic structures using computer axial tomography (CAT-Scan). Benthic fauna analysis showed that the two stations were characterised by different temporal changes in the benthic dynamics according to their geographic location. Using CAT-Scan analysis of sediment cores, we were able to characterise the stability of the sediment column for the two stations in 1999 and 2000. Scan results suggest that colonisation processes were closely linked with the stability of the sediment column. Erosion and redeposition of surficial sediments caused a succession in the formation of biogenic structures. These variations were characterised for the first time using CAT-Scan, which is a nondestructive, rapid, and precise method. Tomographic analysis showed the importance of the production and destruction rates of biogenic structures and the sedimentation rate for the preservation of burrows and potentially reactive components. This study finally demonstrated that each erosional event could be followed by a rapid formation of biogenic structures, allowing the re-oxidation of old deposits
Development of the preterm gut microbiome in twins at risk of necrotising enterocolitis and sepsis
The preterm gut microbiome is a complex dynamic community influenced by genetic and environmental factors and is implicated in the pathogenesis of necrotising enterocolitis (NEC) and sepsis. We aimed to explore the longitudinal development of the gut microbiome in preterm twins to determine how shared environmental and genetic factors may influence temporal changes and compared this to the expressed breast milk (EBM) microbiome. Stool samples (n = 173) from 27 infants (12 twin pairs and 1 triplet set) and EBM (n = 18) from 4 mothers were collected longitudinally. All samples underwent PCR-DGGE (denaturing gradient gel electrophoresis) analysis and a selected subset underwent 454 pyrosequencing. Stool and EBM shared a core microbiome dominated by Enterobacteriaceae, Enterococcaceae, and Staphylococcaceae. The gut microbiome showed greater similarity between siblings compared to unrelated individuals. Pyrosequencing revealed a reduction in diversity and increasing dominance of Escherichia sp. preceding NEC that was not observed in the healthy twin. Antibiotic treatment had a substantial effect on the gut microbiome, reducing Escherichia sp. and increasing other Enterobacteriaceae.
This study demonstrates related preterm twins share similar gut microbiome development, even within the complex environment of neonatal intensive care. This is likely a result of shared genetic and immunomodulatory factors as well as exposure to the same maternal microbiome during birth, skin contact and exposure to EBM. Environmental factors including antibiotic exposure and feeding are additional significant determinants of community structure, regardless of host genetics
Comparison of brief interventions in primary care on smoking and excessive alcohol consumption: a population survey in England.
BACKGROUND: Brief interventions have a modest but meaningful effect on promoting smoking cessation and reducing excessive alcohol consumption. Guidelines recommend offering such advice opportunistically and regularly but incentives vary between the two behaviours.
AIM: To use representative data from the perspective of patients to compare the prevalence and characteristics of people who smoke or drink excessively and who receive a brief intervention.
DESIGN AND SETTING: Data was from a representative sample of 15 252 adults from household surveys in England.
METHOD: Recall of brief interventions on smoking and alcohol use, sociodemographic information, and smoking and alcohol consumption patterns were assessed among smokers and those who drink excessively (AUDIT score of â„8), who visited their GP surgery in the previous year.
RESULTS: Of 1775 smokers, 50.4% recalled receiving brief advice on smoking in the previous year. Smokers receiving advice compared with those who did not were more likely to be older, female, have a disability, have made more quit attempts in the previous year (compared with no attempts: one attempt), and have greater nicotine dependence but were less likely to have no post-16 qualifications. Of 1110 people drinking excessively, 6.5% recalled receiving advice in their GP surgery on their alcohol consumption in the previous year. Those receiving advice compared with those who did not had higher AUDIT scores and were less likely to be female.
CONCLUSION: Whereas approximately half of smokers in England visiting their GP in the past year report having received advice on cessation, <10% of those who drink excessively report having received advice on their alcohol consumption
A deep learning approach to photoâidentification demonstrates high performance on two dozen cetacean species
We thank the countless individuals who collected and/or processed the nearly 85,000 images used in this study and those who assisted, particularly those who sorted these images from the millions that did not end up in the catalogues. Additionally, we thank the other Kaggle competitors who helped develop the ideas, models and data used here, particularly those who released their datasets to the public. The graduate assistantship for Philip T. Patton was funded by the NOAA Fisheries QUEST Fellowship. This paper represents HIMB and SOEST contribution numbers 1932 and 11679, respectively. The technical support and advanced computing resources from University of Hawaii Information Technology ServicesâCyberinfrastructure, funded in part by the National Science Foundation CC* awards # 2201428 and # 2232862 are gratefully acknowledged. Every photoâidentification image was collected under permits according to relevant national guidelines, regulation and legislation.Peer reviewedPublisher PD
Towards the development of ecosystem-based indicators of mangroves functioning state in the context of the EU water framework directive
European Water Framework Directive is enforced in five tropical French Oversea Territories where mangroves are present. Developing bioindication tools to support the ecosystem-based management approach of the Directive is needed. A series of expert workshops was organized and led to the proposal of a strategy and of an applied research program to develop bioindication tools. The proceedings of the workshops are presented as a case study, as this is the first time such an integrative ecosystem-based approach is proposed in mangroves, combining structural and functional aspects, from forest structure to benthic community functioning
A review of the state of the art in tools and techniques used to evaluate remanufacturing feasibility
Remanufacturing often seems a sensible approach for companies looking to adopt sustainable business
plans to achieve long term success. However, remanufacturing must not be treated as a panacea for
achieving a sustainable business, as issues such as market demand, product design, end of life condition
and information uncertainty can affect the success of a remanufacturing endeavour. Businesses therefore
need to carefully assess the feasibility of adopting remanufacturing before committing to a particular
activity or strategy. To aid this decision process, a number of tools and techniques have been published by
academics. However, there is currently not a formal review and comparison of these tools and how they
relate to the decision process.
The main research objective of this study has therefore been to identify tools and methods which have
been developed within academia to support the decision process of assessing and evaluating the viability
of conducting remanufacturing, and evaluate how they have met the requirements of the decision stage.
This has been achieved by conducting a content analysis. Three bibliographic databases were searched
(Compendex, Web of Science and Scopus) using a structured keyword search to identify relevant literature.
The identified tools were then split into 6 categories based upon the specific decision stages and
applications, then evaluated against a set of key criteria which are, the decision factors (economic,
environmental, social) and the inclusion of uncertainty. The key finding of this study has been that
although decision factors are generally well covered, operational tools and the use of uncertainty are
often neglected
Lack of access to chemotherapy for colon cancer: multiplicative disadvantage of being extremely poor, inadequately insured and African American
RÎle de la diversité fonctionnelle de la communauté à Macoma balthica (estuaire du Saint-Laurent, Québec, Canada) sur les flux biogéochimiques à l'interface eau-sédiment et sur le mélange particulaire
RĂSUMĂ : L ' objectif de cette thĂšse de doctorat est de caractĂ©riser et de quantifier l'effet des
groupes fonctionnels de bioturbation dominants de la communauté à M balthica et de leur
diversité, sur les flux biogéochimiques à l' interface eau-sédiment (oxygÚne, carbone organique
dissous, ammonium, nitrate, phosphate), le remaniement sédimentaire et les communautés
microbiennes. Les groupes fonctionnels de la communauté à M balthica de l'estuaire du Saint
Laurent (Québec, Canada) ont été définis selon leur mode de remaniement sédimentaire: Les
biodiffuseurs, Macoma balthica et Mya arenaria, et le diffuseur Ă galerie, Nereis virens. Les
mesures ont été réalisées dans des microcosmes expérimentaux répliqués avec les groupes
fonctionnels isolĂ©s (allopatrie) et assemblĂ©s (sympatrie). Ceux-ci ont Ă©tĂ© soumis aux mĂȘmes
conditions expérimentales sur toute la durée de l'expérience ( 40 jours). Les effets ont été
comparés à des sédiments sans organisme servant de contrÎle. Les organismes ont été
introduits avec des biovolumes identiques, déterminés à partir des densités naturelles.
L'espace d'occupation par les macro-invertébrés était donc similaire pour chaque traitement.
Les rĂ©sultats montrent clairement, qu'Ă biovolume identique, les biodiffuseurs et le diffuseur Ă
galerie ont des effets différents sur la stimulation des flux biogéochimiques, le transport des
particules vers le fond des terriers et l' activité bactérienne. Les effets du diffuseur à galerie,
variant avec le temps, sont nettement supérieurs en raison de la dynamique spatio-temporelle
des structures biogÚnes et des activités d' irrigation, ainsi que de sa profondeur
d'enfouissement maximale. Des différences de profondeurs d'enfouissement expliquent par
ailleurs les variabilités intra-fonctionnelles observées entre les deux biodiffuseurs sur les flux
d' ammonium et de nitrate et sur l' activité bactérienne. Les deux groupes fonctionnels
combinés (diffuseur à galeries + biodiffuseurs) ont des effets importants sur les paramÚtres
mesurés, souvent supérieurs aux effets attendus par simple additivité. Les interactions
spatiales positives entre les deux groupes fonctionnels expliquent ces effets. Les intensités des
interactions affectant essentiellement les flux de nitrate, de phosphate, d' ammonium et
d'oxygĂšne montrent une nouvelle fois, qu ' Ă biovolume identique, la profondeur
d' enfouissement de chaque groupe fonctionnel et l' organisation spatiale entre groupes
fonctionnels apparaissent effectivement comme des facteurs clés dans la stimulation des
processus biogéochimiques sédimentaires. Les résultats obtenus, directement comparables du
fait de l'utilisation de biovolume identique, valident donc l'approche fonctionnelle pour l'Ă©tude
de la bioturbation et ses effets sur les flux biogéochimiques, le remaniement sédimentaire et
les communautés bactériennes. De nouvelles voies de recherche sont proposées pour (i)
développer l'approche fonctionnelle dans le cadre d'études basées sur les échanges à l'interface
eau-sédiment, (ii) affiner la notion de biovolume, et (iii) approfondir les effets des relations
entre groupes fonctionnels au sein d'une communauté, sur le fonctionnement des sédiments
cĂŽtiers. ABSTRACT : The objective of this Ph.D. thesis is to characterise and quantify the effects of the
dominant functional groups of the Macoma balthica community, maintained separately and in
various combinations, on: i) biogeochemical fluxes at the sediment-water interface (oxygen,
dissolved organic carbon, ammonium, nitrate, phosphate), ii) sediment mixing, and iii)
bacterial communities. The functional groups of the M balthica community of the St
Lawrence estuary (Quebec, Canada) were defined according their sediment mixing mode: two
biodiffusers (M balthica and Mya arenaria) and one gallery-diffuser (Nereis virens) were
studied. Experiments were performed in replicated microcosms with the functional groups
being either isolated (allopatry) and combined (sympatry); control microcosms contained
sediment but no macrofauna. Ali treatments were subjected to identical experimental
conditions over the duration of the experiment (40 days). Microcosms contained similar
biovolumes of organisms, these volumes being determined from natural densities. The space
occupied by macro-invertebrates was thus similar in ail treatments. The results c\early show
that the biodiffusers and the gallery-diffuser, at similar biovolumes, have different effects on
the stimulation of biogeochemical fluxes, on particle transport towards deeper layers, and on
bacterial activity. The effects of the gallery-diffuser are highest and vary over time, due to the
spatio-temporal dynamic of biogenic structures and irrigation activities, and to different
maximal burrowing depths. The different burrowing depths of the two biodiffusers also
explain the observed intra-functional variation in nitrate and ammonium fluxes , and in
bacterial activity. The combination of both functional groups (gallery-diffuser+biodiffusers)
has important effects on measured parameters, the latter often being higher th an would be
predicted based on additive effects. Positive spatial interactions between the two functional
groups explain these effects. The interactions between functional groups, which essentially act
on nitrate, phosphate, ammonium and oxygen fluxes, suggest that, at similar biovolumes, the
burrowing depth of each functional group and the spatial organisation of these groups are key
factors in the stimulation of sedimentary biogeochemical processes. The results obtained are
directly comparable due to the use of similar biovolumes, and thus validate the functional
approach for the study of bioturbation and its effects on biogeochemical fluxes, sediment
mixing and bacterial communities. Further research is proposed to (i) develop the functional
approach for studies based only on solute exchange at the sediment-water interface, (ii) refine
the notion of biovolume, and (iii) examine in more detail the effects of relationships between
functional groups within a benthic community on coastal sediment functioning
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