If Dark Matter is made of Weakly Interacting Massive Particles (WIMPs) with masses below
∼
20
GeV, the corresponding nuclear recoils in mainstream WIMP experiments are of energies too close, or ...below, the experimental threshold. Gas Time Projection Chambers (TPCs) can be operated with a variety of target elements, offer good tracking capabilities and, on account of the amplification in gas, very low thresholds are achievable. Recent advances in electronics and in novel radiopure TPC readouts, especially micro-mesh gas structure (Micromegas), are improving the scalability and low-background prospects of gaseous TPCs. Here we present TREX-DM, a prototype to test the concept of a Micromegas-based TPC to search for low-mass WIMPs. The detector is designed to host an active mass of
∼
0.300
kg of Ar at 10 bar, or alternatively
∼
0.160
kg of Ne at 10 bar, with an energy threshold below 0.4 keVee, and is fully built with radiopure materials. We will describe the detector in detail, the results from the commissioning phase on surface, as well as a preliminary background model. The anticipated sensitivity of this technique may go beyond current experimental limits for WIMPs of masses of 2–8 GeV.
Anthropogenic marine debris is one of the major worldwide threats to marine ecosystems. The EU Marine Strategy Framework Directive (MSFD) has established a protocol for data collection on marine ...debris from the gut contents of the loggerhead sea turtle (Caretta caretta), and for determining assessment values of plastics for Good Environmental Status (GES). GES values are calculated as percent turtles having more than average plastic weight per turtle. In the present study, we quantify marine debris ingestion in 155 loggerhead sea turtles collected in the period 1995–2016 in waters of western Mediterranean (North-east Spain). The study aims (1) to update and standardize debris ingestion data available from this area, (2) to analyse this issue over two decades using Zero-altered (hurdle) models and (3) to provide new data to compare the only GES value available (off Italian waters). The composition of marine debris (occurrence and amounts of different categories) was similar to that found in other studies for the western Mediterranean and their amounts seem not to be an important threat to turtle survival in the region. Model results suggest that, in the study area, (a) period of stranding or capture, (b) turtle size and (c) latitude are significant predictors of anthropogenic debris ingestion (occurrence and amount) in turtles. The GES value for late juvenile turtles (CCL>40 cm) has decreased in the last ten years in the study area, and this is very similar to that obtained in Italian waters. We also provide a GES value for early juvenile turtles (CCL≤40 cm) for the first time. Recommendations arising from this study include ensuring use of (1) the standardized protocol proposed by the MSFD for assessing marine debris ingestion by loggerhead sea turtles and (2) the ecology of the turtles (neritic vs oceanic), rather than their size, to obtain GES values.
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•EU proposes Caretta caretta as indicator of pollution in the Mediterranean Sea.•Debris contents in turtle guts are similar in the whole western Mediterranean.•Slight decrease of plastic ingestion by turtles in the Valencia region.•Ten years period, size and latitude are good predictors for debris ingestion by turtles.•A proper use of the standardized protocol proposed by EU is necessary.
Understanding the factors influencing the ingestion of marine debris by the loggerhead sea turtle, Caretta caretta, will help in a better use of this species as an indicator of pollution in the Mediterranean Sea, as proposed by the EU Marine Strategy Framework Directive.
Antarctic minke whales, Balaenoptera bonaerensis, breed in tropical and temperate waters of the Southern Hemisphere in winter and feed in Antarctic grounds in the austral summer. These seasonal ...migrations could be less defined than those of other whale species, but the evidence is scanty. We quantitatively describe the epibiotic fauna of Antarctic minke whales and explore its potential to trace migrations. Seven species were found on 125 out of 333 examined Antarctic minke whales captured during the last Antarctic NEWREP-A expedition in the Southern Ocean: the amphipod Balaenocyamus balaenopterae (prevalence = 22.2%), the copepod Pennella balaenoptera (0.6%); three coronulid, obligate barnacles, Xenobalanus globicipitis (11.1%), Coronula reginae (8.7%), C. diadema (0.9%); and two lepadid, facultative barnacles, Conchoderma auritum (9.0%) and C. virgatum (0.3%). Species with prevalence > 8% exhibited a modest increase in their probability of occurrence with whale body length. Data indicated positive associations between coronulid barnacles and no apparent recruitment in Antarctic waters. All specimens of X. globicipitis were dead, showing progressive degradation throughout the sampling period, and a geographic analysis indicated a marked drop of occurrence where the minimum sea surface temperature is < 12 °C. Thus, field detection -with non-lethal methodologies, such as drones- of coronulid barnacles, especially X. globicipitis, on whales in the Southern Ocean could evince seasonal migration. Future investigations on geographical distribution, growth rate, and degradation (for X. globicipitis) could also assist in timing whales' migration.
•Most tuberculosis (TB) units reported changes in their TB team operations.•TB patients diagnosed during COVID-19 showed more extended pulmonary forms.•Latent TB infections in children household ...contacts were higher in 2020.•Active TB in children household contacts were higher in 2020.
The impact of COVID-19 on the diagnosis and management of tuberculosis (TB) patients is unknown.
Participating centres completed a structured web-based survey regarding changes to TB patient management during the COVID-19 pandemic. The study also included data from participating centres on patients aged ≥18 diagnosed with TB in 2 periods: March 15 to June 30, 2020 and March 15 to June 30, 2019. Clinical variables and information about patient household contacts were retrospectively collected.
A total of 7 (70%) TB units reported changes in their usual TB team operations. Across both periods of study, 169 patients were diagnosed with active TB (90 in 2019, 79 in 2020). Patients diagnosed in 2020 showed more frequent bilateral lesions in chest X-ray than patients diagnosed in 2019 (P = 0.004). There was a higher percentage of latent TB infection and active TB among children in households of patients diagnosed in 2020, compared with 2019 (P = 0.001).
The COVID-19 pandemic has caused substantial changes in TB care. TB patients diagnosed during the COVID-19 pandemic showed more extended pulmonary forms. The increase in latent TB infection and active TB in children of patient households could reflect increased household transmission due to anti-COVID-19 measures.
Aggressive behavior of bottlenose dolphins (Tursiops truncatus) towards conspecifics is widely described, but they have also often been reported attacking and killing harbour porpoises (Phocoena ...phocoena) around the world. However, very few reports exist of aggressive interactions between bottlenose dolphins and other cetacean species. Here, we provide the first evidence that bottlenose dolphins in the western Mediterranean exhibit aggressive behavior towards both striped dolphins (Stenella coeruleoalba) and Risso's dolphins (Grampus griseus). Necropsies and visual examination of stranded striped (14) and Risso's (2) dolphins showed numerous lesions (external rake marks and different bone fractures or internal organ damage by blunt trauma). Indicatively, these lessons matched the inter-tooth distance and features of bottlenose dolphins. In all instances, these traumatic interactions were presumed to be the leading cause of the death. We discuss how habitat changes, dietary shifts, and/or human colonization of marine areas may be promoting these interactions.
In regenerative dentistry, stem cell-based therapy often requires a scaffold to deliver cells and/or growth factors to the injured site. Graphene oxide (GO) and silk fibroin (SF) are promising ...biomaterials for tissue engineering as they are both non toxic and promote cell proliferation. On the other hand, periodontal ligament stem cells (PDLSCs) are mesenchymal stem cells readily accessible with a promising use in cell therapy. The purpose of this study was to investigate the effects of composite films of GO, SF and GO combined with fibroin in the mesenchymal phenotype, viability, adhesion and proliferation rate of PDLSCs. PDLSCs obtained from healthy extracted teeth were cultured on GO, SF or combination of GO and SF films up to 10 days. Adhesion level of PDSCs on the different biomaterials were evaluated after 12 h of culture, whereas proliferation rate of cells was assessed using the MTT assay. Level of apoptosis was determined using Annexin-V and 7-AAD and mesenchymal markers expression of PDLSCs were analyzed by flow cytometry. At day 7 of culture, MTT experiments showed a high rate of proliferation of PDLSCs growing on GO films compared to the other tested biomaterials, although it was slightly lower than in plastic (control). However PDLSCs growing in fibroin or GO plus fibroin films showed a discrete proliferation. Importantly, at day 10 of culture it was observed a significant increase in PDLSCs proliferation rate in GO films compared to plastic (
P
< 0.05), as well as in GO plus fibroin compared to fibroin alone (
P
< 0.001). Flow cytometry analysis showed that culture of PDLSCs in fibroin, GO or GO plus fibroin films did not significantly alter the level of expression of the mesenchymal markers CD73, CD90 or CD105 up to 168 h, being the cell viability in GO even better than obtained in plastic. Our findings suggest that the combination of human dental stem cells/fibroin/GO based-bioengineered constructs have strong potential for their therapeutic use in regenerative dentistry.
Simultaneous determination of fertility hormones in saliva using disposable immunosensing platforms and a custom designed field-portable dual potentiostat.
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•Simultaneous determination ...of progesterone and luteinizing hormone in saliva samples.•Disposable immunoplatforms and custom designed field-portable dual potentiostat.•LODs of 1.7 pg mL−1 and 0.10 mIU mL-1 for P4 and LH, respectively, in less than 1 h.•Accurate determination of both target hormones in saliva samples.
This work describes a new electroanalytical device for the simultaneous and reliable determination of two fertility relevant hormones (luteinizing hormone, LH, and progesterone, P4) in saliva. The device is constructed using a custom designed and field-portable potentiostat where dual disposable immunosensing platform are connected. The immunosensors are based on sandwich-type and competitive immunoassays implemented onto magnetic microbeads (MBs) functionalized with Neutravidin and Protein G for the determination of LH and P4, respectively. Amperometric detection performed at −0.20 V vs the Ag pseudo-reference electrode using the H2O2/hydroquinone (HQ) system was employed as the transduction technique after placing the MBs with immunocomplexes for each target hormone on the appropriate working electrode of screen-printed dual carbon electrodes (SPdCEs). The method exhibits high sensitivity and selectivity for the target hormones providing detection limits of 1.7 pg mL−1 and 0.10 mIU mL−1 for P4 and LH, respectively, with a 1 h test time. The applicability of the method was confirmed by determining both hormones in saliva samples from different volunteers providing results comparable to those obtained using amperometric transduction with a commercial potentiostat and with ELISA methodologies involving the same immunoreagents for each target hormone.
Diseases associated to external parasitosis are scarcely reported in sea turtles. During the last decades several organism have been documented as a part of normal epibiont community connected to sea ...turtles. The copepod Balaenophilus manatorum has been cited as a part of epibiont fauna with some concern about its parasitic capacity. This study serves three purposes, i.e. (i) it sheds light on the type of life style that B. manatorum has developed with its hosts, particularly turtles; (ii) it makes a cautionary note of the potential health risks associated with B. manatorum in sea turtles under captivity conditions and in the wild, and (iii) it provides data on effective treatments against B. manatorum.
We report for the first time a massive infestation of the copepod B. manatorum and subsequent acute mortality in a group of loggerhead sea turtle hatchlings. Four-month-old turtles from a head-starting program started exhibiting excitatory and fin rubbing behavior preceding an acute onset of lethargy, skin ulceration and death in some animals. All the individuals (n = 57) were affected by severe copepod load and presented different degrees of external macroscopic skin lesions. The ventral area of front flippers, axillar and pericloacal skin were mostly affected, and were the main parasite distribution regions. Copepods were also detected on plastron and carapace sutures. The gut contents of B. manatorum reacted positively for cytokeratin, indicating consumption of turtle skin. Severe ulcerative necrotic dermatitis and large amount of bacteria presence were the major histopathological findings.
Individual fresh water immersion for 10 min and lufenuron administration (0.1 ppm) to the water system every 2 weeks proved effective for removing turtle parasites and to control re-infestation, respectively. The results from our study clearly indicated that B. manatorum individuals consume turtle skin. The pathological effects of this agent and the potential implications in sea turtle conservation and management are discussed.
A highly sensitive real-time PCR (qPCR) procedure, targeting the phosphatidylcholine-specific phospholipase C gene (
pc-plc), was developed for specific detection and quantification of strains ...belonging to
Bacillus cereus group. The target region was selected based on the enterotoxigenic profiles of 75
Bacillus strains. The inclusivity and exclusivity of the RTi-PCR assay were assessed with 59 isolates of the
B. cereus group, 16 other
Bacillus spp., and 4 non-
Bacillus strains. The assay was also used to construct calibration curves for different food matrices, and it had a wide quantification range of 6 log units using both serial dilutions of purified DNA and calibrated cell suspensions of
B. cereus CECT 148
T. The detection limit for
B. cereus in artificially contaminated liquid egg and reconstituted infant formula was about 3
CFU per reaction or 60
CFU/ml of food, with a relative accuracy of 86.27% to 116.12% in artificially contaminated liquid egg. Naturally contaminated food samples were tested for the presence of
B. cereus with the standard method, a conventional PCR and the new developed RTi-PCR assay. Results showed that the new developed RTi-PCR assay is very suitable for detection and quantification of strains of
B. cereus group in food samples without an enrichment step.
This study reports for the first time on the whole epibiont fauna of loggerhead marine turtles, Caretta caretta, in the western Mediterranean, analysing the factors that account for the ...predictability and composition of the assemblage. A total of 104 loggerhead turtles stranded along the coasts of eastern Spain during 1995–2006 were surveyed for epibionts. A total of 39 epibiont taxa were identified, three of them being new records for loggerhead turtles: Bittium sp., Idotea metallica and Jassa sp. The assemblage was composed of a group of 27 facultative taxa that use turtles as any inanimate buoyant substrate, and 12 taxa that have developed more specific associations to marine turtles, including six species that occur in marine turtles exclusively, two that dwell also on other hosts, and four that can also survive as free-living forms but have developed a strong association with marine turtles. Hierarchical clustering and Similarity Profile Analysis based on the occurrence of 166 epibiont taxa from nine available surveys indicated that the epibiont assemblages from loggerhead turtles in the western Mediterranean (WM) are similar to those from Central Mediterranean (CM), but significantly different from turtles surveyed in the eastern Mediterranean and the Atlantic. The subset of epibionts occurring on WM and CM turtles is defined by a combination of geographic factors (exclusive Mediterranean epibiont taxa) and ecological factors (relative absence of littoral-benthic taxa). Loggerhead turtles from WM and CM apparently exploit both pelagic and benthic habitats in similar fashion, representing a homogeneous unit for epibiont recruitment.
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