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Innovative and renewable polymers and additives are the focus of increased research due to public and environmental pressure. There has been a recent uptick in interest from scientists in biobased 'green' plasticizers that can be covalently bonded to replace harmful and migratory phthalate-based plasticizers. Vegetable oils (VOs) are one of the biosources, as they are both plentiful and sustainable. This review aims to highlight the synthesis methods for soy-based polyesters. Therefore, the chemistry of soybean oil as a polymeric material and its role in the synthesis of polyesters derived from soybeans are the primary topics of this review. This review covers the many ways in which soybean oil and its derivatives can be used to synthesize polyester, either directly or indirectly. Highlights * The need for sustainable polymers is explored. * Soybean oil-based polyesters are covered. * Modification and chemistry to convert soybean oil into polyester are described. * Applications of soybean-based polyesters are provided. KEYWORDS biopolymers, polyesters, soybean oil, sustainable polymers, synthesis, 1 I INTRODUCTION At the current pace of usage, fossil fuels will be used up by 2050. (1,2) This is why the use of bio-based feedstock is gaining popularity in [...]

Traditional adhesives made using urea or phenol formaldehyde are toxic to humans and the environment, and as a result, the industry is very interested in developing bio-based adhesives. Polyurethane (PU)-based adhesives are very attractive due to their strong bonding strength, and thermal and chemical stability. Polyols derived from petrochemicals are one of the most important constituents in PU-based adhesives. Current trends are to find an alternative for petrochemical-based polyols without compromising the important characteristics of adhesives. In this research, PU adhesives were prepared using soybean oil-based polyol and isocyanate. Three different diols such as 1,2-ethanediol (EDO), 1,4-butanediol (BDO), and 1,6-hexanediol (HDO) were used to study the effect of crosslinking, amount of crosslinkers (diols), and diol's chain length on the properties of bio-based adhesives. The adhesive's lap shear strength using metallic and wood coupons was measured. The BDO-based bio-adhesives showed the best bonding strength compared to EDO and HDO adhesives. The mechanical strength was observed to be increasing with an increase in the amount of diols up to a certain concentration and then started decreasing. On the oakwood, the bonding strength was increased from 3 to 6.36 MPa after incorporating 10 wt% of BDO which was the highest bonding strength observed among all the other adhesives. The thermal and chemical stability of these adhesives were also studied. Structural characterization confirms no significant changes after being immersed in different solvents for 24 h. This work introduces a sustainable alternative to petroleum-based adhesives using polyols from vegetable oil. Highlights * Soybean oil-based polyol was used for adhesives. * 1,2-Ethanediol, 1,4-butanediol, and 1,6-hexanediol were used as crosslinkers. * The bonding strength was measured using wood and metallic coupons. * The bonding strength was observed to be increasing with an increase in the amount of diols. * The highest bonding strength of 6.36 MPa was observed. KEYWORDS adhesives, cross-linkers, diols, polyurethanes, soybean oil, 1 | INTRODUCTION Wood-based materials find extensive application across diverse sectors such as the construction industry, furniture manufacturing, etc. Wood adhesives employed for bonding two surfaces play a pivotal role [...]

Obesity is rapidly becoming an emerging disease in developing countries due to the increasing westernization of societies and change in the lifestyle. The etiology of obesity is said to be multifactorial, with a combination of genetic and environmental factors. Literature has been extensively reviewed to provide a broad overview of obesity. Data for this review were obtained from original articles, review articles and textbooks. Internet search engines were also employed. The years searched were from 1993 to 2008. Obesity, classified in terms of the body mass index and the waist-hip ratio, has several associated co-morbidities such as diabetes mellitus, hypertension, degenerative osteoarthritis and infertility. In Nigeria, there is limited information on obesity. A literature review on obesity is necessary to improve the knowledge about obesity in developing countries, its prevention and its management. [ABSTRACT FROM AUTHOR]

We report molecular genetic studies of three genes involved in early germ-line proliferation in Caenorhabditis elegans that lend unexpected insight into a germ-line/soma functional separation of autosomal/ X-linked duplicated gene pairs. In a genetic screen for germ-line proliferation-defective mutants, we identified mutations in rpl-11.1 (L11 protein of the large ribosomal subunit), pab-1 [a poly(A)-binding protein], and glp-3/eft-3 (an elongation factor 1-[alpha] homolog). All three are members of autosome/X gene pairs. Consistent with a germ-line-restricted function of rpl-11.1 and pab-1, mutations in these genes extend life span and cause gigantism. We further examined the RNAi phenotypes of the three sets of rpl genes (rpl-11, rpl-24, and rpl-25) and found that for the two rpl genes with autosomal/X-linked pairs (rpl-11 and rpl-25), zygotic germ-line function is carried by the autosomal copy. Available RNAi results for highly conserved autosomal/X-linked gene pairs suggest that other duplicated genes may follow a similar trend. The three rpl and the pab-1/2 duplications predate the divergence between C. elegans and C. briggsae, while the eft-3/4 duplication appears to have occurred in the lineage to C. elegans after it diverged from C. briggsae. The duplicated C. briggsae orthologs of the three C. elegans autosomal/X-linked gene pairs also display functional differences between paralogs. We present hypotheses for evolutionary mechanisms that may underlie germ-line/soma subfunctionalization of duplicated genes, taking into account the role of X chromosome silencing in the germ line and analogous mammalian phenomena.