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1.
Mar Environ Res ; 189: 106046, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37295307

RESUMO

Amid the alarming atmospheric and oceanic warming rates taking place in the Arctic, western fjords around the Svalbard archipelago are experiencing an increased frequency of warm water intrusions in recent decades, causing ecological shifts in their ecosystems. However, hardly anything is known about their potential impacts on the until recently considered stable and colder northern fjords. We analyzed macrobenthic fauna from four locations in Rijpfjorden (a high-Arctic fjord in the north of Svalbard) along its axis, sampled intermittently in the years 2003, 2007, 2010, 2013 and 2017. After a strong seafloor warm water temperature anomaly (SfWWTA) in 2006, the abundance of individuals and species richness dropped significantly across the entire fjord in 2007, together with diversity declines at the outer parts (reflected in Shannon index drops) and increases in beta diversity between inner and outer parts of the fjord. After a period of three years with stable water temperatures and higher sea-ice cover, communities recovered through recolonization processes by 2010, leading to homogenization in community composition across the fjord and less beta diversity. For the last two periods (2010-2013 and 2013-2017), beta diversity between the inner and outer parts gradually increased again, and both the inner and outer sites started to re-assemble in different directions. A few taxa began to dominate the fjord from 2010 onwards at the outer parts, translating into evenness and diversity drops. The inner basin, however, although experiencing strong shifts in abundances, was partially protected by a fjordic sill from impacts of these temperature anomalies and remained comparatively more stable regarding community diversity after the disturbance event. Our results indicate that although shifts in abundances were behind important spatio-temporal community fluctuations, beta diversity variations were also driven by the occurrence-based macrofauna data, suggesting an important role of rare taxa. This is the first multidecadal time series of soft-bottom macrobenthic communities for a high-Arctic fjord, indicating that potential periodic marine heatwaves might drive shifts in community structure, either through direct effects from thermal stress on the communities or through changes in environmental regimes led by temperature fluctuations (i.e. sea ice cover and glacial runoff, which could lead to shifts in primary production and food supply to the benthos). Although high-Arctic macrobenthic communities might be resilient to some extent, sustained warm water anomalies could lead to permanent changes in cold-water fjordic benthic systems.


Assuntos
Ecossistema , Estuários , Humanos , Temperatura , Água , Oceanos e Mares , Regiões Árticas
2.
Anim Microbiome ; 5(1): 30, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264469

RESUMO

BACKGROUND: High latitude seeps are dominated by Oligobrachia siboglinid worms. Since these worms are often the sole chemosymbiotrophic taxon present (they host chemosynthetic bacteria within the trophosome organ in their trunk region), a key question in the study of high latitude seep ecology has been whether they harbor methanotrophic symbionts. This debate has manifested due to the mismatch between stable carbon isotope signatures of the worms (lower than -50‰ and usually indicative of methanotrophic symbioses) and the lack of molecular or microscopic evidence for methanotrophic symbionts. Two hypotheses have circulated to explain this paradox: (1) the uptake of sediment carbon compounds with depleted δC13 values from the seep environment, and (2) a small, but significant and difficult to detect population of methanotrophic symbionts. We conducted 16S rRNA amplicon sequencing of the V3-V4 regions on two species of northern seep Oligobrachia (Oligobrachia webbi and Oligobrachia sp. CPL-clade), from four different high latitude sites, to investigate the latter hypothesis. We also visually checked the worms' symbiotic bacteria within the symbiont-hosting organ, the trophosome, through transmission electron microscopy. RESULTS: The vast majority of the obtained reads corresponded to sulfide-oxidizers and only a very small proportion of the reads pertained to methane-oxidizers, which suggests a lack of methanotrophic symbionts. A number of sulfur oxidizing bacterial strains were recovered from the different worms, however, host individuals tended to possess a single strain, or sometimes two closely-related strains. However, strains did not correspond specifically with either of the two Oligobrachia species we investigated. Water depth could play a role in determining local sediment bacterial communities that were opportunistically taken up by the worms. Bacteria were abundant in non-trophosome (and thereby symbiont-free) tissue and are likely epibiotic or tube bacterial communities. CONCLUSIONS: The absence of methanotrophic bacterial sequences in the trophosome of Arctic and north Atlantic seep Oligobrachia likely indicates a lack of methanotrophic symbionts in these worms, which suggests that nutrition is sulfur-based. This is turn implies that sediment carbon uptake is responsible for the low δ13C values of these animals. Furthermore, endosymbiotic partners could be locally determined, and possibly only represent a fraction of all bacterial sequences obtained from tissues of these (and other) species of frenulates.

4.
J Family Med Prim Care ; 12(4): 694-700, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37312788

RESUMO

Background: Healthcare workers (HCWs) are at the front line of the Coronavirus disease (COVID-19) outbreak response. They have faced great risks to both physical and mental health. We aimed to assess the psychological effect of COVID-19 among ancillary hospital staff. Methods: A cross-sectional study was conducted among 267 on-duty ancillary hospital staff using a semi-structured questionnaire to assess their psychological status and risk perception. In addition, their knowledge, attitude, and practices (KAP) and risk perception were also assessed. The General Health Questionnaire (GHQ-12) was used to screen for psychological distress. Results: Among 267 participants, the mean (±SD) age was 33.5 (7.6) years. The majority knew about the symptoms of COVID-19 (88.4%), droplet spread (99.3%), and the importance of isolation (99.3%). About 35.2% were worried about infecting family members, while 26.2% were worried about colleagues at the frontline. Only 38.9% of them had a good knowledge score. Participants with high school and above education level had significantly good knowledge about COVID-19 (OR = 1.99; 95% CI = 1.17- 3.39) than those with primary school or below. Being female (OR 1.99; 95% CI 1.17-3.39) and working with COVID-19 patients (OR 3.88, 95% CI 1.77-8.47, P = 0.001) was associated with psychological distress. Conclusion: The ancillary hospital staff had insufficient knowledge regarding the risk factors of COVID-19 but possessed positive attitudes and practices. Continued health education and appropriate psychological interventions may improve understanding and reduce psychological distress.

5.
Heliyon ; 9(3): e14232, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36967935

RESUMO

We used ancient DNA (aDNA) extraction methods to sequence museum voucher samples of Oligobrachia webbi, a frenulate siboglinid polychaete described from a northern Norwegian fjord over fifty years ago. Our sequencing results indicate a genetic match with the cryptic seep species, Oligobrachia haakonmosbiensis (99% pairwise identity for 574 bp mtCOI fragments). Due to its similarity with O. webbi, the identity of O. haakonmosbiensis has been a matter of debate since its description, which we have now resolved. Furthermore, our results demonstrate that chemosynthesis-based siboglinids, that constitute the bulk of the biomass at Arctic seeps are not seep specialists. Our data on sediment geochemistry and carbon and nitrogen content reveal reduced conditions in fjords/sounds, similar to those at seep systems. Accumulation and decomposition of both terrestrial and marine organic matter results in the buildup of methane and sulfide that apparently can sustain chemosymbiotic fauna. The occurrence of fjords and by extension, highly reducing habitats, could have led to Arctic chemosymbiotic species being relatively generalist with their habitat, as opposed to being seep or vent specialists. Our stable isotope analyses indicate the incorporation of photosynthetically derived carbon in some individuals, which aligns with experiments conducted on frenulates before the discovery of chemosynthesis that demonstrated their ability to take up organic molecules from the surrounding sediment. Since reduced gases in non-seep environments are ultimately sourced from photosynthetic processes, we suggest that the extreme seasonality of the Arctic has resulted in Arctic chemosymbiotic animals seasonally changing their degree of reliance on chemosynthetic partners. Overall, the role of chemosynthesis in Arctic benthos and marine ecosystems and links to photosynthesis may be complex, and more extensive than currently known.

6.
J Travel Med ; 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36715149

RESUMO

Following the COVID-19 pandemic, there has been a sharp increase in rabies cases and deaths. Rabies outbreaks are being reported worldwide. Multiple disruptions in Rabies control occurred during the pandemic, significantly affecting lower-income countries. Countries need to develop specific action plans to become 'rabies free' by 2030.

7.
Clin Epidemiol Glob Health ; 17: 101113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935532

RESUMO

Background: Vaccine hesitancy is of considerable concern as it threatens the great potential of a vaccine against COVID-19. This study aims to determine factors associated with community health workers' willingness to participate in clinical trials of COVID-19 vaccine, and their vaccination intention, in India. Methods: A cross-sectional study was conducted among 377 community health workers using self-administered anonymous questionnaire during the lockdown periods in India. Participant's socio-demographics, willingness-to-participate in COVID-19 vaccine trials, intention to accept COVID-19 vaccine were recorded in a Likert scale. Data were analysed descriptively, and a multivariate logistic regression model was used to investigate factors associated with willingness to participate and accept the vaccine. Results: Among 377 CHWs, 70 (19%) intended to participate in COVID-19 vaccine trial, 151 (40%) responded positively regarding their intention to get vaccinated. Those with knowledge on development of COVID-19 vaccine [aOR 3.05 (95% CI: 1.18-7.88), p = 0.021], and men [aOR 3.69 (95% CI: 1.51-8.97), p = 0.004] were more willing to participate in clinical-trial, while an undergraduate degree, and trust in domestic vaccines were identified as deterrents for the same. Perceiving COVID-19 as risk [aOR 2.31 (95% CI: 1.24-4.31), p = 0.009], and male gender [aOR 2.39 (95% CI: 1.17-4.88), p = 0.017] were factors associated with intention to get vaccinated. Respondents who had knowledge about COVID-19 virus were less likely to uptake the hypothetical vaccine [aOR 0.32 (95% CI: 0.12-0.88), p = 0.027]. Conclusions: Increasing knowledge regarding COVID-19 is not enough to improve vaccine acceptance rates. Targeted interventions addressing socio-demographic determinants related to COVID-19 vaccination should help improve acceptance.

8.
J Family Med Prim Care ; 9(9): 4942-4948, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33209826

RESUMO

BACKGROUND: The concept of emotional intelligence has gained great popularity in the last few decades. With significant rise in stress and other emotional disturbances among students, it becomes necessary to determine whether high emotional intelligence could help manage perceived stress better. This study aims to assess emotional intelligence and perceived stress among undergraduate students of Arts and Science colleges, to determine the association of emotional intelligence with perceived stress, academic performance, and selected socio-demographic factors. METHODS AND MATERIAL: Using multistage sampling, 720 students aged 18 years and above were selected from four colleges in Puducherry. Emotional intelligence and perceived stress were assessed using standard self-administered questionnaires "The Schutte Self-Report Emotional Intelligence Test (SEIT)" and "Perceived Stress Scale (PSS-14)," respectively. RESULTS: The median (IQR) Emotional Intelligence score and Perceived Stress score were 127 (114-137) and 43 (39-47), respectively. The study was not able to establish a significant association between emotional intelligence and perceived stress. A weak significant correlation existed between emotional intelligence and academic performance. Multiple variable analysis revealed gender, year of study, volunteering with youth organizations, and mother's occupation to be significantly associated with emotional intelligence (p < 0.05). CONCLUSIONS: Women, final year students and those who volunteered with youth organizations had higher emotional intelligence. Children of mothers who were employed in knowledge-intensive occupations were more emotionally intelligent. Academic performance had a weak positive significant correlation with emotional intelligence.

9.
Ecol Evol ; 10(3): 1339-1351, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32076518

RESUMO

Frenulate species were identified from a high Arctic methane seep area on Vestnesa Ridge, western Svalbard margin (79°N, Fram Strait) based on mitochondrial cytochrome oxidase subunit I (mtCOI). Two species were found: Oligobrachia haakonmosbiensis, and a new, distinct, and undescribed Oligobrachia species. The new species adds to the cryptic Oligobrachia species complex found at high latitude methane seeps in the north Atlantic and the Arctic. However, this species displays a curled tube morphology and light brown coloration that could serve to distinguish it from other members of the complex. A number of single tentacle individuals were recovered which were initially thought to be members of the only unitentaculate genus, Siboglinum. However, sequencing revealed them to be the new species and the single tentacle morphology, in addition to thin, colorless, and ringless tubes indicate that they are juveniles. This is the first known report of juveniles of northern Oligobrachia. Since the juveniles all appeared to be at about the same developmental stage, it is possible that reproduction is either synchronized within the species, or that despite continuous reproduction, settlement, and growth in the sediment only takes place at specific periods. The new find of the well-known species O. haakonmosbiensis extends its range from the Norwegian Sea to high latitudes of the Arctic in the Fram Strait. We suggest bottom currents serve as the main distribution mechanism for high latitude Oligobrachia species and that water depth constitutes a major dispersal barrier. This explains the lack of overlap between the distributions of northern Oligobrachia species despite exposure to similar current regimes. Our results point toward a single speciation event within the Oligobrachia clade, and we suggest that this occurred in the late Neogene, when topographical changes occurred and exchanges between Arctic and North Atlantic water masses and subsequent thermohaline circulation intensified.

10.
PeerJ ; 7: e7398, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410307

RESUMO

BACKGROUND: High primary productivity in the midst of high toxicity defines hydrocarbon seeps; this feature usually results in significantly higher biomass, but in lower diversity communities at seeps rather than in the surrounding non-seep benthos. Qualitative estimates indicate that this dichotomy does not necessarily hold true in high latitude regions with respect to megafauna. Instead, high latitude seeps appear to function as local hotspots of both megafaunal diversity and abundance, although quantitative studies do not exist. In this study, we tested this hypothesis quantitatively by comparing georeferenced seafloor mosaics of a seep in the southwestern Barents Sea with the adjacent non-seep seafloor. METHODS: Seafloor images of the Svanefjell seep site and the adjacent non seep-influenced background seabed in the southwestern Barents Sea were used to construct georeferenced mosaics. All megafauna were enumerated and mapped on these mosaics and comparisons of the communities at the seep site and the non-seep background site were compared. Sediment push cores were taken in order to assess the sediment geochemical environment. RESULTS: Taxonomic richness and abundance were both considerably higher at the seep site than the non-seep location. However, taxa were fewer at the seep site compared to other seeps in the Barents Sea or the Arctic, which is likely due to the Svanefjell seep site exhibiting relatively low seepage rates (and correspondingly less chemosynthesis based primary production). Crusts of seep carbonates account for the higher diversity of the seep site compared to the background site, since most animals were either colonizing crust surfaces or using them for shelter or coverage. Our results indicate that seeps in northern latitudes can enhance local benthic diversity and this effect can take place even with weak seepage. Since crusts of seep carbonates account for most of the aggregating effect of sites experiencing moderate/weak seepage such as the study site, this means that the ability of seep sites to attract benthic species extends well beyond the life cycle of the seep itself, which has important implications for the larger marine ecosystem and its management policies.

11.
Sci Rep ; 9(1): 1762, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30741962

RESUMO

A newly discovered cold seep from the Lofoten-Vesterålen margin (Norwegian Sea) is dominated by the chemosymbiotrophic siboglinid Oligobrachia haakonmosbiensis like other high latitude seeps, but additionally displays uncharacteristic features. Sulphidic bottom water likely prevents colonization by cnidarians and sponges, resulting in fewer taxa than deeper seeps in the region, representing a deviation from depth-related trends seen among seeps elsewhere. O. haakonmosbiensis was present among carbonate and barite crusts, constituting the first record of frenulates among hard substrates. The presence of both adults and egg cases indicate that Ambylraja hyperborea skates use the site as an egg case nursery ground. Due to sub-zero ambient temperatures (-0.7 °C), we hypothesize that small, seepage related heat anomalies aid egg incubation and prevent embryo mortality. We place our results within the context of high-latitude seeps and suggest they exert evolutionary pressure on benthic species, thereby selecting for elevated exploitation and occupancy of high-productivity habitats.

12.
PLoS One ; 13(12): e0209273, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30592732

RESUMO

We provide the first detailed identification of Barents Sea cold seep frenulate hosts and their symbionts. Mitochondrial COI sequence analysis, in combination with detailed morphological investigations through both light and electron microscopy was used for identifying frenulate hosts, and comparing them to Oligobrachia haakonmosbiensis and Oligobrachia webbi, two morphologically similar species known from the Norwegian Sea. Specimens from sites previously assumed to host O. haakonmosbiensis were included in our molecular analysis, which allowed us to provide new insight on the debate regarding species identity of these Oligobrachia worms. Our results indicate that high Arctic seeps are inhabited by a species that though closely related to Oligobrachia haakonmosbiensis, is nonetheless distinct. We refer to this group as the Oligobrachia sp. CPL-clade, based on the colloquial names of the sites they are currently known to inhabit. Since members of the Oligobrachia sp. CPL-clade cannot be distinguished from O. haakonmosbiensis or O. webbi based on morphology, we suggest that a complex of cryptic Oligobrachia species inhabit seeps in the Norwegian Sea and the Arctic. The symbionts of the Oligobrachia sp. CPL-clade were also found to be closely related to O. haakonmosbiensis symbionts, but genetically distinct. Fluorescent in situ hybridization and transmission electron micrographs revealed extremely dense populations of bacteria within the trophosome of members of the Oligobrachia sp. CPL-clade, which is unusual for frenulates. Bacterial genes for sulfur oxidation were detected and small rod shaped bacteria (round in cross section), typical of siboglinid-associated sulfur-oxidizing bacteria, were seen on electron micrographs of trophosome bacteriocytes, suggesting that sulfide constitutes the main energy source. We hypothesize that specific, local geochemical conditions, in particular, high sulfide fluxes and concentrations could account for the unusually high symbiont densities in members of the Oligrobrachia sp. CPL-clade.


Assuntos
Bactérias , Poliquetos/microbiologia , Animais , Regiões Árticas , Bactérias/genética , Temperatura Baixa , DNA Mitocondrial , Noruega , Oceanos e Mares , Filogenia , Poliquetos/anatomia & histologia , Poliquetos/ultraestrutura , RNA Bacteriano , RNA Ribossômico 16S , Simbiose
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