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Insects like Drosophila produce a second brain adapted to the form and behavior of a larva. Neurons for both larval and adult brains are produced by the same stem cells (neuroblasts) but the larva possesses only the earliest born neurons produced from each. To understand how a functional larval brain is made from this reduced set of neurons, we examined the origins and metamorphic fates of the neurons of the larval and adult mushroom body circuits. The adult mushroom body core is built sequentially of γ Kenyon cells, that form a medial lobe, followed by α’β’, and αβ Kenyon cells that form additional medial lobes and two vertical lobes. Extrinsic input (MBINs) and output (MBONs) neurons divide this core into computational compartments. The larval mushroom body contains only γ neurons. Its medial lobe compartments are roughly homologous to those of the adult and same MBONs are used for both. The larval vertical lobe, however, is an analogous “facsimile” that uses a larval-specific branch on the γ neurons to make up for the missing α’β’, and αβ neurons. The extrinsic cells for the facsimile are early-born neurons that trans-differentiate to serve a mushroom body function in the larva and then shift to other brain circuits in the adult. These findings are discussed in the context of the evolution of a larval brain in insects with complete metamorphosis.

The search for a renewable substitute to petroleum‐based products has fueled increasing research on lignin, an under‐utilized product from pulping processes. In this work, lignin was copolymerized with acrylamide (AM) and diallyldimethylammonium chloride (DADMAC) under acidic conditions with Na2S2O8 as an initiator, generating a cationic water‐soluble lignin‐g‐P(AM)‐g‐P(DADMAC) copolymer. The optimal reaction conditions, using a 5×4 factorial design experiment, were determined to be an AM/DADMAC/lignin molar ratio of 5.5:2.4:1, 90 °C, 0.26 mol L−1 of lignin, and pH 2. Under the optimal reaction conditions, the resulting lignin‐g‐P(AM)‐g‐P(DADMAC) copolymer was 83 % soluble in an aqueous solution (at 10 g L−1) and at neutral pH. The copolymer had a charge density of 1.27 meq g−1, molecular weight of (1.33±0.08) ×106, an AM grafting ratio of 112 wt %, and a DADMAC grafting ratio of 20 wt %. In addition, the activation energy for producing this copolymer as well as the thermal and rheological properties of the copolymer were determined. The flocculation performance of lignin‐g‐P(AM)‐g‐P(DADMAC) copolymer was evaluated in a kaolin suspension, which showed that the lignin copolymer had a comparable flocculation efficiency with the synthetic analogue of P(AM)‐g‐P(DADMAC) at pH 6.

There is a growing need to utilize lignin (i.e., wasted material) from the pulping industry in the production of value-added products and to develop cost-effective and environmentally friendly processes for removing dyes from wastewater effluents. In this context, lignin can be modified to gain anionic charges, which can successfully remove cationic dyes from wastewater. In this study, lignin was extracted from thermomechanical pulp (softwood) via periodate treatment, and then the extracted lignin was oxidized using 30 wt % nitric acid concentration at 80 °C for 1.5 h, which resulted in oxidized lignin with the charge density and solubility of 3.02 mequiv/g and 97% (at a 1 wt % lignin concentration), respectively. The oxidized lignin was used for removing ethyl violet and basic blue cationic dyes from simulated wastewater effluents. It was observed that the dye removals were in the ranges of 70–80 wt % for ethyl violet and of 80–95 wt % for basic blue, while the COD removals were in the ranges of 60–70% f...

Lignin produced in the kraft pulping process is insoluble in water at neutral pH, which limits its application in industry. In this paper, kraft lignin (KL) was copolymerized with acrylic acid (AA) in an aqueous solution to produce a water soluble lignin-based copolymer. The copolymerization was carried out using K2S2O8–Na2S2O3 as the initiator under alkaline aqueous conditions, and the influence of the reaction parameters, i.e. initiator dosage, reaction time and temperature, mole ratio of acrylic acid to lignin and reaction concentration, on resultant lignin copolymers were investigated. The mechanism of copolymerization of kraft lignin with acrylic acid was also discussed in this work. The resultant lignin copolymer was characterized by Fourier Transform Infrared (FTIR) spectrophotometry and Nuclear Magnetic Resonance (NMR). The successful copolymerization of AA and KL was confirmed by the new absorption peak of carboxyl anions in the FTIR spectrum and new peaks in the 1H-NMR spectrum. At optimal conditions, the charge density and molecular weight of lignin copolymer reached 1.86 meq g−1 and 46 421 g mol−1, respectively, and the solubility of lignin after reaction was increased from 1.80 g L−1 to 100 g L−1 at neutral pH.

Africa is grappling with poverty and unemployment. Virtually every sector of the economy is underdeveloped. African females can significantly contribute to the improvement of socioeconomic conditions in Africa considering their active traditional and historical roles in development. However, most females are not entering the formal sector of the economy and indeed the professions because of lack of or inadequate education. Many do not go to school and most do not go beyond elementary education. A significant number of girls drop out of school due to unplanned or unwanted pregnancy and sexually transmitted infections (STIs) including HIV/AIDs. This paper proposes reinvigoration of virginity rituals as a strategy for enhancing girls’ participation in education and formal wage sector employment. The paper argues that revitalized virginity rituals will serve as a sociocultural incentive for girls to stay longer in school, qualify for participation in formal wage labor force and contribute more meaningfully to national development. Revitalized virginity rituals will result in a healthier African society in that it will significantly reduce sex-related vices including unplanned and unwanted teen pregnancies, complications associated with abortion and childbirth to under-aged adolescents, STIs and HIV/AIDS. The study is informed by a review of extant literature and data on women and development, women and reproductive health, women and education, and virginity rituals in Africa. DOI: 10.5901/mjss.2016.v7n1s1p155

Background Hot water hydrolysis process is commercially applied for treating wood chips prior to pulping or wood pellet production, while it produces hydrolysis liquor as a by-product. Since the hydrolysis liquor is dilute, the production of value-added materials from it would be challenging. Results In this study, acidification was proposed as a viable method to extract (1) furfural and acetic acid from hot water hydrolysis liquor and (2) lignin compounds from the liquor. The thermal properties of the precipitates made from the acidification of hydrolysis liquor confirmed the volatile characteristics of precipitates. Membrane dialysis was effective in removing inorganic salts associated with lignin compounds. The purified lignin compounds had a glass transition temperature (Tg) of 180–190 °C, and were thermally stable. Conclusions The results confirmed that lignin compounds present in hot water hydrolysis liquor had different characteristics. The acidification of hydrolysis liquor primarily removed the volatile compounds from hydrolysis liquor. Based on these results, a process for producing purified lignin and precipitates of volatile compounds was proposed. Electronic supplementary material The online version of this article (doi:10.1186/s13068-017-0729-9) contains supplementary material, which is available to authorized users.