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Madagascar is an isolated oceanic island characterized by high degrees of endemism at all taxonomic levels. The waters surrounding Madagascar are still poorly studied for benthic marine diatom assemblages. The aim of our study was to analyse the taxonomic biodiversity and molecular phylogeny of the diatom assemblages of the Nosy Be archipelago in terms of their ubiquity/rarity. A total of 65 samples from 14 sampling sites were collected from the Nosy Be and Nosy Tanikely islands in June/July 2014. Diatom identification, based on light and electron microscopic examination, revealed 332 diatom taxa. From those, ∼90 strains were isolated and successfully cultured. So far, DNA has been extracted and one chloroplast gene (rbcL) sequenced from 21 strains in order to reconstruct their single gene phylogeny. Taxa selected for sequencing and the preliminary phylogeny are from genera considered common benthic and planktonic forms in the marine littoral: Bellerochea, Melosira, Paralia, Triceratium, Navicula, Hippodonta, Auricula, Nitzschia, Cocconeis, and some araphids. For each site, Shannon and Simpson biodiversity indices were calculated. Diatom assemblages of Nosy Be were characterized by high biodiversity. The most abundant species was Cocconeis scutellum. Whereas some of the cultured taxa seem to represent cosmopolitan or zonal forms: e.g., Bellerochea malleus, Triceratium dubium, Melosira lineata, Paralia crawfordii, or Nitzschia inconspicua, most of the taxa isolated in culture and sequenced have not been observed in earlier works based on use of molecular markers. The dominant taxa were generally those with broad geographic distribution with global/Indo-Pacific affinities. Amongst all 332 taxa, only 35% have been identified to the species level. Many of the taxa identified to the generic level may turn out to represent taxa new to science after further SEM examination and DNA sequencing. [ABSTRACT FROM AUTHOR]

Batch experiments were performed to investigate the removal of Cu2+, Cl-, and 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution using chitosan-modified bentonite. When the chitosan was loaded on the bentonite, the inter-layer space of the montmorillonite increased and the adsorption efficiency enhanced, as chitosan contains large numbers of -NH2 and -OH functional groups that could serve as coordination sites to bind heavy metals. In this study, the bentonite that was prepared through three procedures: Na2CO3 treatment, thermal treatment and compound treatment, was modified by chitosan. Experimental results demonstrated that the average removal rates of Cu2+, Cl-, and 2,4-D effectively were 94.87 %, 86.19 % and 91.06 %, respectively. [ABSTRACT FROM AUTHOR]

Objectives Notch signalling plays an important role in many cell activities, involving proliferation, migration, differentiation and cell death. The aim of this study was to investigate effects of such signalling on adipogenesis of mouse adipose-derived stem cells (m ASCs). Materials and methods Jagged1 (50 and 100 ng/ml) was added to m ASCs to activate Notch signalling, 2 days before adipogenic induction. At 5 and 7 days after induction, oil red-O staining was performed to evaluate lipid accumulation. Then real-time PCR was performed to examine expression of Notch downstream genes ( Notch-1, -2, Hes-1 and Hey-1) and adipogenic transcription factor ( PPAR-γ). Expressions of Hes-1 and PPAR-γ at protein level were confirmed by immunofluorescence staining. Results Our data indicated that Jagged1 promoted adipogenic differentiation of m ASCs. Moreover, Jagged1 also increased expression of Notch downstream genes and PPAR-γ. Expressions of Hes-1 and PPAR-γ were found to be enhanced in Jagged1 pre-treated m ASCs when compared to controls. Discussion The results led to the conclusion that activation of Notch signalling had stimulated adipogenesis of m ASCs in the presence of adipogenic medium by promoting expression of PPAR-γ. [ABSTRACT FROM AUTHOR]

• MoS 2 was prepared by hydrothermal method using excessive oxalic acid concentration. • Nature of synthesis creates a defective MoS 2 structure. • Structurally defective MoS 2 is highly active towards HER in acidic solution. Two-dimensional layered molybdenum sulfide (MoS 2) is highly attractive as electrocatalyst for high purity hydrogen production because of its intrinsic properties and favorable cost-benefit ratio. Notably, electrocatalytic activity of MoS 2 strongly depends on exposed edges and density of defect sites. Here, we report the preparation of MoS 2 nanoflakes through an oxalic acid assisted-hydrothermal method. A comparatively excessive amount of oxalic acid was used as an alternative strategy for the preparation of MoS 2. XRD, TEM, RAMAN, and XPS results revealed that as-prepared MoS 2 is highly defective with presence of unsaturated S and abundant exposed edges. As a result, structurally defective MoS 2 nanoflakes exhibit high activity for HER with low overpotential of 214 mV at 10 mA/cm2, a small Tafel slope of 52 mV/decade and excellent stability. [ABSTRACT FROM AUTHOR]

Ndour, A.; Ba, K.; Almar, A.; Almeida, P.; Sall, M.; Diedhiou; P.M., Floc'h, F.; Daly, C.; Grandjean, P.; Boivin, J-P; Castelle, B.; Marieu, V.; Biausque, M.; Detandt, G.; Tomety Folly, S.; Bonou, F.; Capet, X.; Garlan, T., Marchesiello, P.; Benshila, R.; Diaz, H.; Bergsma, E.; Sadio, M.; Sakho, I., and Sy, B.A., 2020. On the natural and anthropogenic drivers of the Senegalese (West Africa) low coast evolution: Saint Louis Beach 2016 COASTVAR experiment and 3D modeling of short term coastal protection measures. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 583-587. Coconut Creek (Florida), ISSN 0749-0208. West Africa's low and densely populated coasts crystallize most of the environmental and societal problems and resulting vulnerability. It is becoming urgent to document this coast and the natural and anthropogenic forces to understand its evolution. Saint Louis is a historic (World Heritage) city located on the Langue de Barbarie, a 10 km sandspit at the mouth of the Senegal River. Because of its location, it is vulnerable (erosion, flooding) to river and ocean variability. This intermediate barred microtidal beach is located in a storm-free intertropical environment, but is exposed to distant oblique energetic waves from high latitudes, causing one of the highest coastal drifts in the world (∼800,000 m3/year). As part of the COASTVAR project, an intensive international field experiment was conducted in Saint Louis from 4 to 13 December 2016 to quantify the natural protective role played by the sandbar, coastal currents and transient exchanges with the inner shelf. Many instruments have been deployed to measure waves, currents, bathymetry and topography. This article provides an overview on the objectives of the experiment, the deployment and the first results of the modeling of coastal protection strategy. [ABSTRACT FROM AUTHOR]

Lattice parameters of GaAs layers were measured using the Bond method. For samples heavily doped with S and Se, we observed an increase of lattice parameters with respect to the undoped samples. The results are compared with those observed for AlxGa1-xAs:S (Wagner et al.) and both are explained by the influence of free electrons and their redistribution in the conduction band. For Al0.39Ga0.61As, the following values of deformation potentials of the conduction-band minima were obtained: DΓ=-6.7 eV, DL=1.4 eV, and DX=1 eV. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate effects of low-intensity pulsed ultrasound ( LIPUS) on differentiation of adipose-derived stem cells ( ASCs), in vitro. Materials and methods Murine ASCs were treated with LIPUS for either three or five days, immediately after adipogenic induction, or delayed for 2 days. Expression of adipogenic genes PPAR-γ1, and APN, was examined by real-time PCR. Immunofluorescence ( IF) staining was performed to test for PPAR-γ at the protein level. Results Our data revealed that specific patterns of LIPUS up-regulated levels of both PPAR-γ1 and APN mRNA, and PPAR-γ protein. Conclusions In culture medium containing adipogenic reagents, LIPUS enhanced ASC adipogenesis. [ABSTRACT FROM AUTHOR]

Abstract: Obsessive-compulsive disorder (OCD) is a chronic, recurrent, and often disabling disorder. Comorbid emotional and personality disorder are common and can serve to complicate both course of illness and treatment outcome. Controlled trials with adults have shown cognitive-behavior therapy (CBT) that includes exposure and response prevention (ERP) to be highly effective for treating the disorder. It means exposing the patient to the very thing that causes fear and anxiety, and using all his strength to simply accept the experience instead of relying on compulsions to counteract it. The basic concept of CBT is: by changing the behavior, the patient eventually changes how he thinks and feels. CBT usually works fairly quickly, and it relies mostly on action, not insight. In this article we describe a cognitive-behavioral group treatment for both OCD symptoms and comorbid personality disorder. By an evaluable patient analysis; statistically and clinically significant pretreatment to posttreatment change occurred in OCD diagnostic status and severity. Some personality traits also changed. The results of this study, the first to evaluate this dimension of the personality disorders comorbidities in the OCD and their evolution with a behavioural and cognitive psychotherapy, are very encouraging. Indeed, evolution of the fields and facets of the personality changed positively. [Copyright &y& Elsevier]

Following an outbreak of Rift Valley fever (RVF) in south-eastern Mauritania during 1998, entomological investigations were conducted for 2 years in the affected parts of Senegal and Mauritania, spanning the Sénégal River basin. A total of 92 787 mosquitoes (Diptera: Culicidae), belonging to 10 genera and 41 species, were captured in light traps. In Senegal,Culex poicilipes(41%) andMansonia uniformis(39%) were the most abundant species caught, whereasAedes vexans(77%) andCx. poicilipes(15%) predominated in Mauritania. RVF virus was isolated from 63 pools ofCx.poicilipes: 36 from Senegal in 1998 and 27 from Mauritania in 1999. These results are the first field evidence ofCx. poicilipesnaturally infected with RVFV, and the first isolations of this virus from mosquitoes in Mauritania– the main West African epidemic and epizootic area. Additional arbovirus isolates comprised 25 strains of Bagaza (BAG) fromAedes fowleri,Culex neaveiandCx. poicilipes; 67 Sanar (ArD 66707) fromCx. poicilipes; 51 Wesselsbron (WSL) fromAe. vexansand 30 strains of West Nile (WN) fromMa. uniformis, showing differential specific virus–vector associations in the circulation activity of these five arboviruses. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate effects of mechanical compressive force on differentiation of adipose-derived stem cells ( ASCs) in vitro. Materials and methods Mice ASCs were treated with compressive force (2000 με, 1 Hz) for 2 or 6 h after adipogenic induction for 3 days, then oil red O staining was used to examine oil droplet-filled cells. Adipogenic genes, PPAR-γ1 and APN, were examined by real-time PCR and immunofluorescence ( IF) staining was performed to test expression of de- PPAR-γ and ph- PPAR-γ at the protein level. Results Our data showed that mechanical compressive force reduced numbers of oil droplet-filled cells, and down-regulated mRNA levels of both PPAR-γ1 and APN and protein level of PPAR-γ, in ASCs. Conclusions In culture medium containing adipogenic stimuli, mechanical compressive force inhibited adipogenesis of ASCs. [ABSTRACT FROM AUTHOR]

Objectives As mesenchymal stem cells ( MSCs) can be isolated easily from adipose tissues while retaining their self-renewal and multi-potential differentiation capacities, they hold promising possibilities for being applied extensively in tissue engineering. Bone morphogenetic protein ( BMP) family members have been reported to provide instructive signals to MSCs for them to differentiate into several different cell lineages. The study described here aims to investigate whether BMP-4 could promote adipose-derived stem cell ( ASC) differentiation into adipocytes under various concentrations. Materials and methods ASCs were isolated from mouse inguinal adipose pads and cultured in vitro. 10 ng/ml and 50 ng/ml BMP-4 were added to adipogenic media for 8 days. Oil red-O staining, reverse transcription/polymerase chain reaction and immunocytofluorescence staining were performed to examine differentiation of the ASCs. Results As indicated by increased expression of adipogenic and lipogenic genes ( PPAR-γ, APN and LPL) and proteins, 50 ng/ml BMP-4 seemed to induce mASCs to differentiate into the adipo-lineage compared to 10 ng/ml BMP-4, and control groups. In addition, lipid droplets accumulated within the adipocytes under 50 ng/ml BMP-4 stimulation, as shown by oil red-O staining. Conclusions Our present study suggests that BMP-4, as an adipo-inducing factor, promoted adipogenesis of ASCs at higher concentrations (50 ng/ml) and can perhaps be considered as a candidate for use in adipose tissue engineering. [ABSTRACT FROM AUTHOR]

Objectives Based on in vivo studies, low-intensity pulsed ultrasound ( LIPUS) stimulation has been widely used in the clinic for advancing bone growth during healing of non-union alignment, fractures and other osseous defects. In this study, we have investigated osteogenic differentiation of adipose stem cells ( ASCs) regulated by LIPUS, and also in a preliminarily manner, we have discussed diverse effects of different duty ratio parameters. Materials and methods Mouse adipose stem cells were isolated and osteogenically induced. Then they were treated with LIPUS for 10 min/day for 3 days, 5 days and 7 days, respectively. Finally, effects of LIPUS on osteogenic differentiation of the ASCs were analysed by real-time PCR, western blotting and immunofluorescence. Results Our data indicated that LIPUS promoted mRNA levels of runt-related transcription factor 2, osteopontin and osterix in the presence of osteo-induction medium; moreover, protein levels of runt-related transcription factor 2 and osteopontin were upregulated. Conclusions We successfully demonstrated that LIPUS enhanced osteogenesis of ASCs, specially at the duty ratio of 20%. [ABSTRACT FROM AUTHOR]

Summary: Modern systematics can now rely on powerful discriminating techniques, such as cytogenetics. As a result, a growing number of sibling species has been described in a variety of taxa. Among mammals, this is particularly true in rodents. Here, we describe a new species of Taterillus (Rodentia, Gerbillinae), namely Taterillus tranieri sp. n. based on specimens from Mali and Mauritania. Neither external and cranial morphology nor morphometrics taking size and shape into account could lead to a satisfying diagnosis of this species relative to the four West African species known in this genus. Conversely, this new species could be characterized by a very specific karyotype (with 2N=14/15, the lowest diploid number in gerbilline rodents, NFa=22–24) differing from that of its closest relative Taterillus petteri (2N=18/19, NFa=28) by two tandem translocations accompanied by 2 centromere activations/desactivations, one non reciprocal translocation, and three pericentric inversions. In addition to providing non-ambiguous arguments in favour of the description of this taxon as a new biological species, these chromosomal results confirm the complex karyotypic evolution of Taterillus. Furthermore, this study illustrates how cytogenetics can contribute to the description of sibling species and hence to biodiversity. These cryptic taxa also constitute valuable support for evolutionary studies, especially concerning speciation processes. They also represent important issues in applied research such as in conservation biology or pest species control. The routine use of cytogenetics for species characterization will undoubtedly constitute a powerful diagnostic tool in these contexts. [Copyright &y& Elsevier]