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Freshwater in sediment pore fluids and methane seepage from the seafloor have often been observed concurrently in Arctic regions where submarine groundwater discharge (SGD) occurs, with advective flows potentially reintroducing ancient carbon into the modern ocean. It is hypothesized that hydraulic loading by ice sheets enhances submarine groundwater discharge, and subsequently methane transport. In the presence of microbial communities, large amounts of methane can be consumed by the anaerobic oxidation of methane (AOM), inducing precipitation of authigenic carbonates that inherit unique carbon isotopic signatures from methane. At an SGD site offshore Lofoten Islands, northern Norway (ca. 800 meters water depth), in the vicinity of the maximum extent of the Fennoscandian Ice Sheet, we observed a downcore decreasing chlorinity profile and a linear relation between δ18O and δ2H of the porewater, known as the local meteoric water line. This demonstrates a meteoric water contribution to the porewater. We also found methane-derived authigenic carbonates (MDACs) with depleted δ13C values (< -30 ‰ VPDB), suggesting that microbial (or thermogenic) methane was incorporated during MDAC precipitation. Moreover, δ18O values (> 2.5 ‰ VPDB) of MDACs indicate precipitation in the presence of 18O-enriched water, possibly a result of past hydrate dissociation. To assess the carbon cycle and timing of the methane seepage at the Lofoten SGD site, we investigated the radiocarbon contents of Total Organic and Inorganic Carbon in sediments (TOC, TIC), as well as Dissolved Inorganic Carbon (DIC) in porewater from multiple sediment horizons. The radiocarbon contents of DIC have the lowest values among the three carbon pools, in the order of 10-30 percent modern carbon. Their radiocarbon ages (~ 17,000 years BP) are in the order of the Last Glacial Maximum. Consequently, the DIC must have been closed off from the atmosphere due to long groundwater retention times. Alternatively, a methane source low in radiocarbon could have contributed to the DIC pool through AOM. The TIC pool showed radiocarbon content half of that of the TOC in the same sediment horizons, which can be explained by carbonate precipitation from the radiocarbon-depleted DIC pool. To further constrain in situ carbon cycling and advection velocities, a reaction-transport model using mass balance calculations of 12C, 13C and 14C has been applied. Radiocarbon content profiles of the DIC indeed imply the advection of old groundwater into the marine sediment porous media.

The main goal of CAGE 17-2 AMGG cruise was to study the gas-hydrate-bearing system and methane emission off south and east of Spitsbergen in Storfjordrenna and the northern flank of Olga Basin (named here Olga craters) respectively, and in the West Sentralbanken. We addressed this through a comprehensive scientific program comprising dives with the MISO-Tow Cam adapted to the multicorer frame from UiT-NPI (TowCam/Multicorer, TCM), methane measurements in sediments, water column, and in air, sediment coring (multicorer + gravity corer), water column and sediment biogeochemistry, microbiology, micropaleontology, and bathymetric mapping. Cruise CAGE 17-2 was also hosting this year’s AMGG research school cruise with masters, PhD and post-doc students participating. The areas investigated were: Storfjordrenna, Pingos site (ca 380 m water depth),Northern Flank of Olga Basin (ca 140 m water depth)West Sentralbanken (ca 200 m water depth) We planned the following activities during the CAGE 17-2 cruise: EM 302 Simrad swath bathymetry mapping to identify seabed morphology Mapping of flare distributionsCTD stations at different water depths and in different areas for measurements ofocean water masses characteristics, andwater sampling for water/gas chemistry and microbiology investigations across methane seeps.TCM surveys (video-camera) to image seabed fluid flow expressions, sites of bacteria mats, crusts and gas bubbles.Repeated deployments with TCM to sample surficial and shallow sediments with respect to microbiology, geochemistry, biogeochemistry, and micropaleontology.Gravity corer for studying sediment biogeochemistry, biomarkers, microbiology, and foraminifera.Scrape sampling to collect rocks and crusts.Gas Chromatographer (GC) to measure methane concentration in the water and sediment samples.Flasks Restek, Electro-Polished Miniature Canister (1000 cc) for air samples. Part of the cruise was supported by NPD, Oljedirektoratet. Special thanks to Rune Mattingsdal, NPD. The cruise may be known as: CAGE17_2

From the morning of October 28th to the evening of October 28th 2020, fieldwork was performed comprising retrieval of live siboglinid worms for genetic and environmental studies hereunder pore water content of sulphate, sulphide and methane and sediment TOC, TC and isotopes. The working area was a basin located in outer Kvalsund, Troms, northern Norway. A total of 2 box core stations and 2 gravity core stations were obtained and two CTD casts. Echosounding and chirp data were recorded on stations and on transits. The cruise may be known as: CAGE20_WORM

The cruise to the Atlantic-Arctic gateway region is organized and funded through the Geological Survey of Norway (NGU) and focuses on studies of methane leakage at the seafloor on the Mid Norwegian shelf and continental margin. Cruise 20200108 in June 2020 was directed to two areas to study ongoing seepage of hydrocarbons and their controlling factors. Along the Lofoten margin, to investigate the outcropping bedrock structures in two canyons; on the Mid-Norwegian shelf, to inspect a recently discovered seep site. The cruise may be known as: CAGE20_0

From the evening of June 29th to the evening of July 10th 2018, CAGE at the Department of Geology Uit, the Arctic University of Norway, arranged a scientific cruise aimed at investigating methane seep sites by surface sediment sampling, sediment core sampling, plankton sampling and water sampling. The areas for investigation were the Barents Sea (Crater area), Storfjorden Trough (Pingo area),East Greenland Ridge (non-seep, for IODP-proposal) (Leg 1 and 2) and the western Svalbard margin, Vestnesa Ridge, Arctic Ocean and Prins Karls Forland (Leg 3) on R/V “Helmer Hanssen”. The scientific sampling was done within the framework of several ongoing projects at the Department of Geology, University of Tromsø: “CAGE -Centre for Arctic Gas Hydrate, Environment and Climate”-WP6: “Methane Release, Ocean Acidification and CO2” hereunder ocean acidification impact on marine calcifiers (planktic foraminifera and pteropods, methane seeping impact on ocean acidification and productivity, the state of the inorganic and organic biological pump from foraminifera, bottom water temperature change and impact on release of methane, living benthic microfauna studies from seep sites for geochemical investigations for calibrations for paleostudies. A total of 15 gravity cores (c. 60 m),and 31 CTD (conductivity-temperature-depth) casts were performed, 11 plankton net (no. 12 failed because the net was torn completely), 22 boxcore samples x 6 surface samples for each. A total of 137 lines of acoustics and seismics together were performed. Chirp profiles and multi-beam lines were acquired during transits and in surveys mapping of new seep sites northeast of “Crater” area, seep sites in Storfjorden Trough, East Greenland Ridge, seeps in Hinlopen trough and Norske Banken, the east slope of Yermak Plateau, active and inactive pockmarks at Vestnesa Ridge and a small patch off PKF for WP4. All acoustic and seismic investigations were performed with soft-start of all instruments (Echo-sounders, deep-penetrating echosounder (‘Chirp’), Multi-beam echosounder and mini-air gun). The cruise may be known as: CAGE18_3_leg1 CAGE18_3_leg2 CAGE18_3_leg3

This cruise was the second of in total four seasonal cruises with RV Kronprins Haakon in 2019/20 focusing on biology in the project Arven etter Nansen (AeN). This seasonal cruise was named Q4 (Q4= 4th quarter of the year) investigating in total 17 stations of the established AeN transect along 34 E in the Northern Barents Sea and adjacent Arctic Basin from 76 to 82°N (see Fig. 1 below). The cruise addressed objectives of the research foci in RF1 on Physical drivers, RF2 on Human drivers, RF3 on the living Barents Sea and RA-C Technology and method development, and collected a multitude of data along the Nansen Legacy transect which was ice covered except the southernmost station P1. In addition to in situ sampling, on board experiments were conducted to quantify biological processes, rates and interactions that will also be important feeds into modeling work and projections in RF4 The future Barents Sea. The cruise took a variety of continuous ship measurements (Weather station, EK80, EM203, ADCP, thermosalinograph, pCO2 underway) as well as station measurements such as CTD with water samples, biological sampling of the benthos (box corer, benthic trawl), water column (multinet, MIK net, macrozooplankton trawl and many other smaller nets) and sea ice (snow, ice cores, water just underneath sea ice). In addition, experimental work (respiration, grazing and egg production) was conducted in the ship’s laboratories. The chemistry team onboard measured oxygen, nutrients and pH from standard depths on most CTD stations and sea ice samples. The cruise started in Longyearbyen and ended in Tromsø (28.11.-17.12.2019). The sampling began at the deep (>3000 m) northernmost station of the transect, Stn. P7, and continued along the southward transect until station P1, in open water and Atlantic dominated water masses. During the expedition the Barents Sea was characterized by a relatively large sea ice cover with consolidated sea ice all the way from P7 to P2. The Polar Front was located just north of P1. All process stations were sampled (P7-P1) as well as two ice stations: one close to P7 ad one close to P5. At the southernmost station P1, stormy weather challenged sampling, but most tasks were in the end accomplished except of deploying the box corer, sediment trap and the AUV. These operations were considered too challenging due to strong drift and ship movement, and it was not safe to conduct small boat operations. Challenges with the box corer was also experienced at the deep station P7 due to technical issues. In the end, most work was accomplished despite challenging weather, sea ice conditions and some technical issues making this cruise successful in gaining new important knowledge about the Northern Barents Sea in the polar night season which is extremely poorly studied. The overall high biological activity and biomass at this time of the year, November-December, was surprising for most of us.

Taking a bird's eye's view across the globe to understand the different methods to look at vaccine safety surveillance, one thing becomes clear. The commitment to monitor the safety of a vaccine does not stop at the clinical development stage. Rather, awareness, reporting, and research need to be bolstered after the vast population gets exposed to the vaccine. Global collaboration, understanding, and embracing the global best practices will go a long way to ensure safer vaccinations. With the COVID-19 pandemic already creating havoc in minds of all, the panic or unacceptance about the vaccination side effects in the population is undesirable. Adverse events are the unfortunate yet unavoidable element in the journey of a new drug or a vaccine. But since it is a healthy population who are recipients of vaccines, the researchers and PV professionals need to be more mindful of the risk-benefit profile of the vaccine.

Permafrost is defined as perennially frozen ground (soil or rock and included ice and organic material) with a temperature near or below 0°C that remains for at least two consecutive years. Permafrost occurs mainly in high latitudes of the Southern and Northern Hemispheres, but significant area can also be found in the middle- and low-latitude regions. In these areas, the groundwater cycle is mainly controlled by the permafrost layer that may act as an aquiclude and hence block or retard the groundwater flow. However, rapid climate changes which are observed during the last decades, markedly contribute to permafrost degradation. New connections between permafrost and groundwater are expected to form during the permafrost thawing process. This will contribute to enhance permafrost and groundwater interaction and reinforce groundwater discharge. In general, groundwater discharge is a groundwater movement from the saturated ground to the surface water bodies or submarine groundwater inflow into the sea. Increased groundwater discharge may transport a significant amount of nutrients, metals, and gases to land and ocean waters and hence may change their physicochemical parameters. Unfortunately, due to the limited number of studies, understanding the significance of groundwater discharge in the Arctic regions is limited.The study aims to provide a comprehensive review of the present literature data that contribute to better understanding interaction between permafrost and groundwater in the Arctic regions, which are particularly vulnerable to climate changes. This review is focused on permafrost thawing, groundwater discharge, and recharge processes and their implication on the environment. We attempt to answer the following questions: How does permafrost affect groundwater discharge and recharge? Does permafrost act as a hindrance for groundwater? How does progressive global warming and thereby permafrost thawing impact the groundwater discharge? How significant is groundwater discharge? How important is the transport of different solutes to the environment by groundwater discharge?Based on the literature, we can conclude that the degradation of permafrost greatly influences hydrological systems in cold zones. Permafrost has a strong impact on fluid dynamics caused by negligible hydraulic conductivity. This relationship, beyond all physical, chemical, and biogeochemical responses, contributes to the formation of complex permafrost–groundwater interactions. Permafrost degradation strongly affects the ecosystem through direct and indirect impacts on the transport and cycles of different compounds, elements, and ions. Moreover, all processes are dependent on topography, geomorphology, tectonics, and surface hydrology. Research conducted in other than Arctic permafrost areas also indicated that permafrost thawing is the cause of enhanced groundwater recharge and discharge rates, which resulted in deeper water tables and groundwater flow paths. However, comprehensible and systematic studies are still needed for global assessment also in terms of searching for interdependencies between different regions.This belongs to Project No. 2019/34/H/ST10/00645 "Submarine Groundwater Discharge in a Changing Arctic Region: Scale and Biogeochemical impact", which is supported by the Norwegian Financial Mechanism and Polish national Basic Research Program.

The Nansen Legacy Q3 cruise, 5-27 August 2019, initiated the seasonal investigations of the Nansen Legacy transect. The transect represent an environmental gradient going through the northern Barents Sea, and included 7 process stations (P1-P7) lasting 6-53 hrs. CTD stations were taken to increase the hydrographic resolution on the transect. The program included measurements and sampling from the atmosphere, sea ice, ocean and sea floor. Data collected ranged from physical observations, chemical, biological and geological data collection, and the aim was to link observations and measurements to improve our understanding of the systems involving both climate, human impacts and the ecosystems. Deployment of moorings and gliders extended the observational capacity in time and space, outside the cruise period.

Background: Vaccine hesitancy is of considerable concern as it threatens the great potential of a vaccine against COVID-19. Community health workers (CHWs) bridge the gap between the community and the health care system. Their intention to get vaccinated will not only affect them but will also affect the community’s perception of the vaccine. This study aims to understand the intention to get vaccinated against COVID-19 among community health care workers in India and its determinants.Methods: A web-based, cross-sectional study was conducted among 357 community health workers using snowball sampling. A self-administered anonymous questionnaire was shared with study participants across major geographical regions in India through social media during the first wave (November-December 2020).Results: Among 357 community health workers, 208 (58%) responded positively regarding their intention to get a COVID-19 vaccine. Graduate [aOR 2.26 (95% CI: 1.27-4.01), p=0.006] and post-graduate participants [aOR 2.85 (95% CI: 1.43-5.68), p=0.003], those with lower risk perception [aOR 1.86 (95% CI: 1.03-3.35), p=0.038] and respondents who trusted the healthcare system [aOR 2.60 (95% CI:1.59-4.26), pConclusions: Increasing knowledge regarding the COVID-19 vaccine might not be enough to improve vaccine acceptance rates. Enhancing trust among community health workers in the healthcare system and regarding the available vaccines seem necessary. In addition, targeted interventions addressing socio-demographic determinants related to COVID-19 vaccination should help improve acceptance of the vaccine.

Anoxic marine sediments contribute a significant amount of dissolved iron (Fe2+) to the ocean which is crucial for the global carbon cycle. Here, we investigate iron cycling in four Arctic cold seeps where sediments are anoxic and sulfidic due to the high rates of methane-fueled sulfate reduction. We estimated Fe2+ diffusive fluxes towards the oxic sediment layer to be in the range of 0.8 to 138.7 μmole/m2/day and Fe2+ fluxes across the sediment-water interface to be in the range of 0.3 to 102.2 μmole/m2/day. Such variable fluxes cannot be explained by Fe2+ production from organic matter–coupled dissimilatory reduction alone. We propose that the reduction of dissolved and complexed Fe3+ as well as the rapid formation of iron sulfide minerals are the most important reactions regulating the fluxes of Fe2+ in these cold seeps. By comparing seafloor visual observations with subsurface pore fluid composition, we demonstrate how the joint cycling of iron and sulfur determines the distribution of chemosynthesis-based biota.

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., The deepwater (~1,200 m depth), high Arctic (79°N) Vestnesa seep contains two frenulate species: Oligobrachia haakonmosbiensis and a potentially new species. Multitentaculate adults and unitentaculate juveniles of the new species were present. We propose that bottom currents serve as the main dispersal mechanism for high latitude frenulates, although water depth functions as a major distributional barrier.

Cold seeps can support unique faunal communities via chemosynthetic interactions fueled by seabed emissions of hydrocarbons. Additionally, cold seeps can enhance habitat complexity at the deep seafloor through the accretion of methane derived authigenic carbonates (MDAC). We examined infaunal and megafaunal community structure at high-Arctic cold seeps through analyses of benthic samples and seafloor photographs from pockmarks exhibiting highly elevated methane concentrations in sediments and the water column at Vestnesa Ridge (VR), Svalbard (79° N). Infaunal biomass and abundance were five times higher, species richness was 2.5 times higher and diversity was 1.5 times higher at methane-rich Vestnesa compared to a nearby control region. Seabed photos reveal different faunal associations inside, at the edge, and outside Vestnesa pockmarks. Brittle stars were the most common megafauna occurring on the soft bottom plains outside pockmarks. Microbial mats, chemosymbiotic siboglinid worms, and carbonate outcrops were prominent features inside the pockmarks, and high trophic-level predators aggregated around these features. Our faunal data, visual observations, and measurements of sediment characteristics indicate that methane is a key environmental driver of the biological system at VR. We suggest that chemoautotrophic production enhances infaunal diversity, abundance, and biomass at the seep while MDAC create a heterogeneous deep-sea habitat leading to aggregation of heterotrophic, conventional megafauna. Through this combination of rich infaunal and megafaunal associations, the cold seeps of VR are benthic oases compared to the surrounding high-Arctic deep sea.

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.

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.

International audience; Western Pacific hydrothermal vents will soon be subjected to deep-sea mining and peripheral sites are considered the most practical targets. The limited information on community dynamics and temporal change in these communities makes it difficult to anticipate the impact of mining activities and recovery trajectories. We studied community composition of peripheral communities along a cline in hydrothermal chemistry on the Eastern Lau Spreading Center and Valu Fa Ridge (ELSC-VFR) and also studied patterns of temporal change. Peripheral communities located in the northern vent fields of the ELSC-VFR are significantly different from those in the southern vent fields. Higher abundances of zoanthids and anemones were found in northern peripheral sites and the symbiont-containing mussel Bathymodiolus brevior, brisingid seastars and polynoids were only present in the northern peripheral sites. By contrast, certain faunal groups were seen only in the southern peripheral sites, such as lollipop sponges, pycnogonids and ophiuroids. Taxonomic richness of the peripheral communities was similar to that of active vent communities, due to the presence of non-vent endemic species that balanced the absence of species found in areas of active venting. The communities present at waning active sites resemble those of peripheral sites, indicating that peripheral species can colonize previously active vent sites in addition to settling in the periphery of areas of venting. Growth and mortality were observed in a number of the normally slow-growing cladorhizid stick sponges, indicating that these animals may exhibit life history strategies in the vicinity of vents that differ from those previously recorded. A novel facultative association between polynoids and anemones is proposed based on their correlated distributions.

Deep-sea ecosystems have attracted considerable commercial interest in recent years because of their potential to sustain a diverse range of mankind's industrial needs. If these systems are to be preserved or exploited in a sustainable manner, mapping habitats and species distributions is critical. As biodiversity at cold-seeps or other deep-sea ecosystems is driven by habitat heterogeneity, imagery is the obvious choice for characterizing these systems and has indeed proven extremely valuable towards mapping biogenic habitats formed by dense aggregations of large sized species, such as coral reefs, tubeworm bushes or bivalve beds. However, the acquisition of detailed images with resolution sufficient for reliable identification is extremely time consuming, labor intensive and highly susceptible to logistical issues. We developed a novel method for quickly mapping cold seep fauna and habitats over large areas, at the scale of squares of kilometers. Our method uses multibeam echosounder bathymetry and acoustic backscatter data, both segmented and reclassified based on topographical features and then combined to obtain a raster containing unique values incorporating both backscatter and bathymetry data. Two datasets, obtained from 30 m and 8 m above the seafloor were used and the results from the two datasets were compared. The method was applied to a cold seep community located in a pockmark in the deep Congo channel and we were able to ground truth the accuracy of our method against images of the area. The two datasets, obtained from different altitudes gave varying results: the 8 m altitude dataset reliably predicted tubeworms and carbonate rock, while the 30 m altitude dataset predicted tubeworms and vesicomyid clams. The 30 m dataset was more accurate than the 8 m altitude dataset in predicting distributions of tubeworms. Overall, all the predictions were quite accurate, with at least 90% of predictions being within 5 m of real distributions.

Background: In line with WHO’s END TB strategy and Sustainable Development Goal’s vision, India has set a goal to eliminate tuberculosis by 2025. To meet this goal, intensified case finding is a strategy adopted by India’s national tuberculosis program. This study aimed to determine the proportion of presumptive pulmonary tuberculosis (PPTB) patients among outpatients of a tertiary care center and its association with socio-demographic and behavioral factors.Methods: A hospital based cross-sectional analytical study was done in a tertiary care center during November 2017 among outpatients aged 18 years or above. Known cases of tuberculosis (TB) were excluded. Information on socio-demographic characteristics and TB symptoms was collected using a structured questionnaire. A person with any symptom suggestive of TB, including, cough of any duration, subjective weight loss, and fever at present was considered to have PPTB. Presence of PPTB was reported as proportion with 95% confidence intervals. Association between variables and presumptive pulmonary TB was assessed using chi square test and prevalence ratio with 95% CI.Results: Among 2638 outpatients, 907 (34%) had PPTB. Cough was the most reported symptom (22.9%); followed by fever (10.0%), weight loss (13.9%) and hemoptysis (0.9%). PPTB was found to be significantly higher among males, smokers, alcohol users and patients having a history of contact with any TB patient.Conclusions: One-third of the outpatients had PPTB and this was high. A screening procedure could be incorporated within the hospital policy to identify outpatients with symptoms of TB.

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.

Bioavailable iron is an important micro-nutrient for marine phytoplankton and therefore critical to global biogeochemical cycles. Anoxic marine sediment is a significant source of Fe(II) to the ocean. Here, we investigate how the fluxes of Fe(II), both towards the sedimentary oxic layer and across the sediment-water interface, are impacted by the high concentration and flux of porewater sulfide in cold seep environments. We present new porewater data from four recently documented cold seeps around Svalbard as well as from continental shelves and fjords in northern Norway. We quantitatively investigated porewater data first by calculating the Fe(II) fluxes towards oxidized surface sediments and bottom water and, second, applied a transport-reaction model to estimate the mass balance of several key chemical species. Sedimentary sulfur speciation data from two of the sites were used to constrain Fe(II) consumption in the shallow sediments. We showed that the iron reduction zone is usually confined to the top 10 cm of the sediments from our studied sites due to high sulfate turnover and therefore high sulfide flux. Such a thin iron reduction zone allows proportionally more Fe(II) to reach the bottom water. Rapid precipitation of pyrite occurs at the base of the iron reduction zone, where the downward diffusing Fe(II) meets upward migrating hydrogen sulfide. Dissolved H2 released during pyrite formation stimulates a small but significant rate of sulfate reduction in the same horizon, which results in faster production of hydrogen sulfide and a positive feedback for iron reduction in the shallow sediment. Deeper in the sediment, where sulfate is actively consumed due to anaerobic methane oxidation, no apparent formation of pyrite is observed from the available measurements and our modeling results. This is mostly due to the relatively low availability of Fe(II) as a result of slower turnover of the less active iron mineral phases. Such an observation may contradict the use of pyrite abundance to deduce the sulfate-methane-transition-zone in past sedimentary records. A series of model sensitivity tests were performed to systematically investigate how the Fe(II) dynamics is impacted by higher deposition rate of iron (oxyhydr)oxides minerals on the seafloor and intensifying methane supply. We showed that the increases in iron reduction rate, pyrite formation rate, and Fe(II) flux are expected with higher seafloor iron (oxyhydr)oxides deposition initially. However, complicated feedbacks between Fe(II) production and sulfate reduction pose negative feedbacks to pyrite formation in the sediments. With a larger supply of methane, Fe(II) flux towards the oxic surface sediments is initially intensified by the higher production of hydrogen sulfide until such an interplay is too fast that essentially all reactive iron minerals settled on the seafloor dissolve immediately and dissolved iron is fixed through pyrite precipitation. Such an interplay between Fe(II) and sulfide determines the distribution of animals with chemoautotrophic symbionts which rely on sulfide as their energy source.

The presently active region of the Congo deep-sea fan (around 330,000 km(2)), called the terminal lobes or lobe complex, covers an area of 2500 km(2) at 4700-5100 m water depth and 750-800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers. In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the geology, organic and inorganic geochemistry, and micro- and macro-biology of the terminal lobes of the Congo deep-sea fan. Using this multidisciplinary approach, the morpho-sedimentary features of the lobes were characterized along with the origin and reactivity of organic matter, the recycling and burial of biogenic compounds, the diversity and function of bacterial and archaeal communities within the sediment, and the biodiversity and functioning of the faunal assemblages on the seafloor. Six different sites were selected for this study: Four distributed along the active channel from the lobe complex entrance to the outer rim of the sediment deposition zone, and two positioned cross-axis and at increasing distance from the active channel, thus providing a gradient in turbidite particle delivery and sediment age. This paper aims to provide the general context of this multidisciplinary study. It describes the general features of the site and the overall sampling strategy and provides the initial habitat observations to guide the other in-depth investigations presented in this special issue. Detailed bathymetry of each sampling site using 0.1-1 m resolution multibeam obtained with a remotely operated vehicle (ROV) shows progressive widening and smoothing of the channel-levees with increasing depth and reveals a complex morphology with channel bifurcations, erosional features and massive deposits. Dense ecosystems surveyed in the study area gather high density clusters of two large-sized species of symbiotic Vesicomyidae bivalves and microbial mats. These assemblages, which are rarely observed in sedimentary zones, resemble those based on chemosynthesis at cold-seep sites, such as the active pockmarks encountered along the Congo margin, and share with these sites the dominant vesicomyid species Christineconcha regab. Sedimentation rates estimated in the lobe complex range between 0.5 and 10 cm yr(-1), which is 2-3 orders of magnitude higher than values generally encountered at abyssal depths. The bathymetry, faunal assemblages and sedimentation rates make the Congo lobe complex a highly peculiar deep-sea habitat driven by high inputs of terrigenous material delivered by the Congo channel-levee system. (c) 2016 Elsevier Ltd. All rights reserved. ZAIANGO ANR Congolobe (ANR Blanc SIMI5-6) [11 BS56 030] IFREMER CEA through LSCE U.S. National Science Foundation [OCE-0831156] info:eu-repo/semantics/acceptedVersion

International audience; This study characterizes the habitats and megafaunal community of the Congo distal lobe complex driven by turbidity currents through the use of remotely operated vehicle (ROV) still imagery transects covering distances in the order of kilometers. In this sedimentary, abyssal area about 5000 m deep and 750 km offshore from western Africa, large quantities of deposited organic material supplied by the Congo River canyon and channel support aggregations of large sized foraminifers (Bathysiphon sp.) and vesicomyid clams (Christineconcha regab, Abyssogena southwardae) often associated with methane cold seeps, as well as opportunistic deep-sea scavengers. Additionally, bacterial mats, assumed to be formed by large sulfur-oxidizing filamentous bacteria (Beggiatoa type), and black patches of presumably reduced sediment were seen which are, together with sulfur-oxidizing symbiont-bearing vesicomyids, indicators of sulfide-rich sediments. Habitat and faunal distribution were analyzed in relation to the microtopography obtained with the ROV multibeam echosounder, at three sites from the entrance of the lobe complex where the channel is still deep, to the main, flatter area of turbidite deposition. Specific characteristics of the system influence animal distributions: both the forams and the vesicomyid clams tended to avoid the channels characterized by high-speed currents, and are therefore preferentially located along channel flanks affected by sliding, and on levees formed by channel overspill. Foram fields are found in flat areas and form large fields, whereas the vesicomyids have a patchy distribution and appear to show a preference for regions of local topographical relief such as slide scars or collapsed blocks of sediments, which likely facilitate sulfide exhumation. The colonization of sulfide rich sediments by vesicomyids is limited, but nonetheless was seen to occur in the main deposition area where they have to cope with very high sedimentation rates (up to 20 cm/yr) and frequent turbidity currents. Other biological adaptations to the local conditions likely determine the presence and survival of animals in the system: large agglutinated forams are known to be adept at quickly colonizing disturbed sediment and capitalizing on abundant but irregular food sources, and vesicomyid clams have a mobile lifestyle that enables them to maintain their population in the ever changing landscape of sulfide-rich sediment outcrops. Turbiditic systems appear to be intermediate between other energy rich habitats sustaining chemosynthesis in the deep sea, being locally less stable 2 Please note that this is an author-produced PDF of an article accepted for publication following peer review. The definitive publisher-authenticated version is available on the publisher Web site. in terms of energy supply than cold seeps, limiting the number of cold-seep specialists able to colonize, but constituting a longer lived habitat than food falls. Turbidite fans therefore represent distinct deep sea habitats that contribute to sustaining populations of both chemosynthesis-based and opportunistic taxa in the deep-sea.