In vitro photoprotective, antioxidant and antibacterial activity of Vernonia squarrosa (D. Don) Less

Vernonia squarrosa (D. Don) Less. (Asteraceae) is an ethnomedicinally important plant of unexplored medicinal potential. The Hydro-Methanolic Leaf Extract (HMLE) reveals presence of alkaloids, terpenoid, tannins, phenols, flavonoids, saponins and also cardiac glycosides with notable amount of phenol, flavonoid, ? carotene and lycopene. The high antioxidant activity of HMLE when assessed by 2, 2 diphenyl 1-picrylhydrazyl (DPPH) shows significant EC50 value of 11.63 ± 2.60 µg/ml. Photo-protection efficiency of HMLE was determined and expressed as Sun Protection Factor (SPF). Reasonably high SPF value of 38 (SPF=38 at 200 µg/ml) provides UV blockage up to 98%. HMLE extract was also screened for antibacterial activity against four human pathogenic bacterial strains, Staphylococcus aureus (MTCC 2940), Pseudomonas aeruginosa (MTCC 2453), Bacillus subtilis (MTCC 441), Escherichia coli (MTCC 739). Results showed prominent antibacterial impact on these tested bacteria. Lupeol, a pentacyclic triterpenoid was found to be present as a dominant member in Gas chromatography–mass spectrometry (GC-MS) analysis of HMLE. Lupeol is a pentacyclic triterpenoid compound with diverse pharmaceutical applications. This is the maiden report of bioactive compounds from V. squarrosa highlighting their antibacterial, photoprotective and antioxidant activities.

Multiple factors likely explain variation in investment in sexual reproduction by lake Daphnia populations

Many organisms can reproduce both asexually and sexually. For cyclical parthenogens, periods of asexual reproduction are punctuated by bouts of sexual reproduction, and the timing of the shift from asexual to sexual reproduction has large impacts on fitness and population dynamics. We studied populations of Daphnia dentifera to determine the amount of investment in sexual reproduction as well as the factors associated with variation in investment in sex. To do so, we tracked host density, parasite infections, sexual reproduction, temperature, and light attenuation in 15 lake populations of D. dentifera for three years. We monitored infections by nine common parasites; this is notable since most prior studies on investment in sex and parasitism have focused on a single parasite, even though multiparasite communities are the norm in nature. We found substantial variation in investment in sex, with some populations reproducing entirely asexually throughout the study period and others shifting almost entirely to sexual reproduction by late autumn. We found that higher host density and parasitism were associated with greater investment in sex. Temperature and light attenuation were not as predictive of investment in sex, but received some statistical support. While correlational, our results leverage a large time series dataset and suggest multiple factors likely drive variation in sexual reproduction in this dominant member of lake food webs.

Bioleaching of Pyrrhotite with Bacterial Adaptation and Biological Oxidation for Iron Recovery

The microbially mediated recovery of valuable metals contained in mining waste presents an economical alternative to conventional hydrometallurgical processes. In order to investigate the effect of bacterial adaptation and biological oxidation on bioleaching, the microbially mediated bioleaching of a pyrrhotite sample from mine waste, with indigenous bacteria existing in acid mine drainage, was studied. The indigenous bacteria were sub-cultured repeatedly for iron adaptation, and Acidithiobacillus ferrooxidans was identified as the dominant member of the microbial consortium. The point of zero charge (PZC) of pyrrhotite sampled from mine waste was determined as 3.0. The performance of bioleaching by contact and non-contact biological oxidation was compared by conducting bioleaching under different initial pH (pHini) conditions (2.8 and 3.2). Negatively charged bacteria could be attached onto the pyrrhotite, which has a positive surface charge at lower pHini (2.8) than the PZC (3.0). Bacteria attachment and corrosion pits on the surface of the pyrrhotite residues were observed at pHini of 2.8. Under bacteria-adapted conditions, the leaching concentration of Fe (44.2 mg/L) at pHini of 2.8 was 2.1 times greater than that (21.3 mg/L) at pHini of 3.2. Under non-adapted bacteria conditions, the extent of Fe leaching was not significantly different between the pHini of 2.8 and 3.2. This could be attributed to the fact that the adapted bacteria could more easily attach onto the pyrrhotite surfaces at pHini 2.8, allowing contact biological oxidation during the bioleaching experiments. We demonstrate here that the bioleaching of pyrrhotite could increase Fe recovery through bacterial adaptation and contact biological oxidation.

Not That Close to Mommy: Horizontal Transmission Seeds the Microbiome Associated with the Marine Sponge Plakina cyanorosea

Marine sponges are excellent examples of invertebrate–microbe symbioses. In this holobiont, the partnership has elegantly evolved by either transmitting key microbial associates through the host germline and/or capturing microorganisms from the surrounding seawater. We report here on the prokaryotic microbiota during different developmental stages of Plakina cyanorosea and their surrounding environmental samples by a 16S rRNA metabarcoding approach. In comparison with their source adults, larvae housed slightly richer and more diverse microbial communities, which are structurally more related to the environmental microbiota. In addition to the thaumarchaeal Nitrosopumilus, parental sponges were broadly dominated by Alpha- and Gamma-proteobacteria, while the offspring were particularly enriched in the Vibrionales, Alteromonodales, Enterobacterales orders and the Clostridia and Bacteroidia classes. An enterobacterial operational taxonomic unit (OTU) was the dominant member of the strict core microbiota. The most abundant and unique OTUs were not significantly enriched amongst the microbiomes from host specimens included in the sponge microbiome project. In a wider context, Oscarella and Plakina are the sponge genera with higher divergence in their associated microbiota compared to their Homoscleromorpha counterparts. Our results indicate that P. cyanorosea is a low microbial abundance sponge (LMA), which appears to heavily depend on the horizontal transmission of its microbial partners that likely help the sponge host in the adaptation to its habitat.

The Pacific Islands Forum

This chapter presents a case study of the Pacific Islands Forum (PIF). It examines why the PIF has never established an international parliamentary institution (IPI) in spite of several favourable conditions, such as an increase in authority, a large scope, predominantly democratic member states, a legitimacy crisis in regional governance, and improving conditions for international diffusion. The explanation points to the absence of and contestation about general purpose. Small and recently independent island states blocked region building and occasional IPI proposals by dominant member states (Australia and New Zealand) to protect their sovereignty. The analysis is subdivided into two cases, the 1971–2000 period of initial institutionalization and the period from 2000 onwards during which the Forum experienced deepening integration together with a severe legitimacy crisis.

Immune Response in H. pylori-Associated Gastritis and Gastric Cancer

Helicobacter pylori (H. pylori) is the dominant member of the gastric microbiota and has infected more than half of the human population, of whom 5–15% develop gastric diseases ranging from gastritis and metaplasia to gastric cancer. These diseases always follow inflammation induced by cell surface and intracellular receptors and subsequent signaling, such as the NF-κB pathway and inflammasomes. Some types of immune cells are recruited to enforce an antibacterial response, which could be impeded by H. pylori virulence factors with or without a specific immune cell. Following decreased inflammation, neoplasm may appear with a little immune surveillance and may inhibit antitumor immunity. Therefore, the balance between H. pylori-associated inflammation and anti-inflammation is crucial for human health and remains to be determined. Here, we discuss multiple inflammation and immunoregulatory cells in gastritis and summarize the main immune evasion strategies employed by gastric cancer.

The role of metaphtonymy in verbalizing futurological concepts

The paper touches upon the problem of metaphtonymy in futurological discourse as well as its role in verbalizing futurological concepts FUTURE SHOCK, THE THIRD WAVE, and SUI-CIDE. The investigation aimed to determine the peculiar features of metaphtonymy and de-fine its role in the verbal representation of futurological concepts. The investigation is based on the novels of a prominent American futurologist A. Toffler “The Future Shock,” “The Third Wave” and a famous American publicist P. Buchanan “Suicide of a Superpower: Will America Survive to 2025?”. The techniques employed include conceptual analysis, metaphor, and metonymy modeling. 75 contexts of metaphtonymy of certain types (“metaphor in me-tonymy,” “metonymy in metaphor,” “metonymy, metaphor in metaphor”, “metaphor, meton-ymy, metaphor in metaphor,” etc.) were identified, and all of them proved to be involved in the verbal representation of the futurological concepts. The analysis showed that all the metaphtonymic unities had a hierarchical structure with one prevailing component and one or several subordinate elements. Moreover, metaphors are more likely than metonymies to act as a dominant member of the hierarchy, their target domain or/and source domain being motiva-tors for other components emerging in a metaphtonymic unity. As for the forms of metaphor and metonymy thinking in metaphtonymies under analysis, we found extended metaphors and metonymic chains and clusters. Metaphors (their target or/and source domains) turned to be most active in verbalizing the futurological concepts. The variants of verbalization are as fol-lows: “future shock as a disease,” “the third wave as evolution design,” “suicide as ethnomasochism,” etc.

Trade Liberalisation and Labour Market Adjustment in Botswana

We study the effects of domestic trade liberalisation on labour markets in Botswana. South Africa is the dominant member of the Southern Africa Customs Union. As such, when South Africa liberalised trade in the 1990s, this induced large and plausibly exogenous tariff reductions for the other customs union members, including Botswana. Using labour force surveys from Botswana spanning a decade, we find that trade liberalisation did not affect the relative size of industries in terms of employment. However, trade liberalisation had effects within industries. We find an increase in the prevalence of working in an informal firm and self-employment, but mixed evidence of effects on unemployment. Hours worked decreased in response to trade liberalisation, partially driven by the movement of workers to informal firms. Despite large increases in aggregate income, trade liberalisation is associated with a reduction in monthly income, but the results are imprecise. Our results also suggest that a positive export demand shock, the 2000 African Growth and Opportunities Act, is associated with a reduction in employment in informal firms in the clothing industry.

Novel Wolbachia strains in Anopheles malaria vectors from Sub-Saharan Africa

Anopheles (An.) mosquitoes contain bacteria that can influence Plasmodium parasites. Wolbachia, a common insect endosymbiont, has historically been considered absent from Anopheles but has recently been found in An. gambiae populations. Here, we assessed a range of Anopheles species from five malaria-endemic countries for Wolbachia and Plasmodium infection. Strikingly, we found Wolbachia infections in An. coluzzii, An. gambiae s.s, An. arabiensis, An. moucheti and An. species ‘A’ increasing the number of Anopheles species known to be naturally infected by this endosymbiont. Molecular analysis suggests the presence of phylogenetically diverse novel strains, while qPCR and 16S rRNA sequencing indicates that Wolbachia is the dominant member of the microbiota in An. moucheti and An. species ‘A’. We found no evidence of Wolbachia/Asaia co-infections, and presence of these endosymbionts did not have significant effects on malaria prevalence. We discuss the importance of novel Wolbachia strains in Anopheles and potential implications for disease control.

Hydroxynatropyrochlore, (Na,Сa,Ce)2Nb2O6(OH), a new member of the pyrochlore group from the Kovdor phoscorite–carbonatite pipe, Kola Peninsula, Russia

Hydroxynatropyrochlore, (Na,Сa,Ce)2Nb2O6(OH), is a new Na–Nb–OH-dominant member of the pyrochlore supergroup from the Kovdor phoscorite–carbonatite pipe, Kola Peninsula, Russia. It is cubic, Fd$\bar{3}$m, a = 10.3211(3) Å, V = 1099.46(8) Å3 and Z = 8 (from powder diffraction data) or a = 10.3276(5) Å, V = 1101.5(2) Å3 and Z = 8 (from single-crystal diffraction data). Hydroxynatropyrochlore is a characteristic accessory mineral of the low-carbonate phoscorite in the contact zone of the phoscorite–carbonatite pipe with host foidolite as well as in the carbonate-rich phoscorite and carbonatite of the pipe axial zone. It usually forms zonal cubic or cubooctahedral crystals (up to 0.5 mm in diameter) with irregularly shaped relics of amorphous U–Ta-rich hydroxykenopyrochlore inside. Characteristic associated minerals include rock-forming calcite, dolomite, forsterite, hydroxylapatite, magnetite and phlogopite, accessory baddeleyite, baryte, barytocalcite, chalcopyrite, chamosite–clinochlore, galena, gladiusite, juonniite, ilmenite, magnesite, pyrite, pyrrhotite, quintinite, spinel, strontianite, valleriite and zirconolite. Hydroxynatropyrochlore is pale brown, with an adamantine to greasy lustre and a white streak. The cleavage is average on {111} and the fracture is conchoidal. Mohs hardness is ~5. In transmitted light, the mineral is light brown, isotropic and n = 2.10(5) (λ = 589 nm). The calculated and measured densities are 4.77 and 4.60(5) g cm−3, respectively. The mean chemical composition determined by electron microprobe is: F 0.05, Na2O 7.97, CaO 10.38, TiO2 4.71, FeO 0.42, Nb2O5 56.44, Ce2O3 3.56, Ta2O5 4.73, ThO2 5.73, UO2 3.66, total 97.65 wt.%. The empirical formula calculated on the basis of Nb + Ta + Ti = 2 apfu is (Na1.02Ca0.73Ce0.09Th0.09 U0.05${\rm Fe}_{{\rm 0}{\rm. 02}}^{2 +} $)Σ2.00(Nb1.68Ti0.23Ta0.09)Σ2.00O6.03(OH1.04F0.01)Σ1.05. The simplified formula is (Na,Ca,Ce)2Nb2O6(OH). The mineral dissolves slowly in hot HCl. The strongest X-ray powder-diffraction lines [listed as (d in Å)(I)(hkl)] are as follows: 5.96(47)(111), 3.110(30)(311), 2.580(100)(222), 2.368(19)(400), 1.9875(6)(333), 1.8257(25)(440) and 1.5561(14)(622). The crystal structure of hydroxynatropyrochlore was refined to R1 = 0.026 on the basis of 80 unique observed reflections. The mineral belongs to the pyrochlore structure type A2B2O6Y1 with octahedral framework of corner-sharing BO6 octahedra with A cations and OH groups in the interstices. The Raman spectrum of hydroxynatropyrochlore contains characteristic bands of the lattice, BO6, B–O and O–H vibrations and no characteristic bands of the H2O vibrations. Within the Kovdor phoscorite–carbonatite pipe, hydroxynatropyrochlore is the latest hydrothermal mineral of the pyrochlore supergroup, which forms external rims around grains of earlier U-rich hydroxykenopyrochlore and separated crystals in voids of dolomite carbonatite veins. The mineral is named in accordance with the pyrochlore supergroup nomenclature.