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N-doped biomass-derived porous carbon was synthesized by the pyrolysis of sugarcane-vinasse to develop a novel metal-free catalyst in electrochemical sensing. Vinasse samples were subjected to different pyrolysis temperatures under nitrogen flow to investigate the effect of the pyrolysis temperature on the physical properties of the biomass-derived products. The XPS results displayed that as-pyrolyzed samples contain N atoms with an atomic ratio of 3.02%. While a low surface area of 1.5 m2/g was measured from the sample pyrolyzed at 600 °C, the increase in the temperature yielded a large surface area of 620 m2/g. Additional heat treatment was implemented to tailor N-binding sites. Samples were then used as electroactive catalysts for hydrogen peroxide (H2O2) electrochemical sensing. Vinasse-P-10@N-based sensors showed much-improved sensor performance in a linear range of 0.03–12 mM with a high sensitivity of 208.97 µA mM−1 cm−2.

The present research investigated the relationship between dysfunctional relationship beliefs (DRB) and alexithymia with a particular focus on gender among Turkish college students. Results indicat...

Poplar (Populus tremula) was transformed with a construct carrying an antisense caffeic acidO-methyltransferase (COMT) cDNA (pOMT8) from a tropical pasture legume,Stylosanthes humilis. pOMT8 shows 83% overall homology to the corresponding COMT gene (pPCLA) of poplar. Of the 200 putatively-transformed plants regenerated on selective media after co-cultivation of poplar stem explants withAgrobacterium tumefaciens harbouring a CaMV 35S-antisensepOMT8 construct, a subset of 20 plants were randomly chosen for further analysis. PCR and Southern blot analysis demonstrated the stable integration of T-DNA into the genome of these plants. Antisense expression ofpOMT8 resulted in reductions in total COMT activity in the majority of the transgenic plants with the lowest total COMT activities (61–70% of untransformed control plants) being observed in four transgenic plants. The composition of lignin in transgenic plants was also changed, as detected by reductions in the content of syringyl units using infrared spectroscopy. However, no changes were found in the amount of insoluble lignin in transgenic plants as compared to untransformed control plants. These results indicate the potential of thepOMT8 gene to partially suppress COMT activity and modify the composition of lignin in transgenic poplar.

Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin content.

Retrorectal cyst-hamartoma is a relatively rare disease. Total excision of the cyst is indicated to prevent infection and malign proliferation. We present a case of retrorectal cyst-hamartoma in a 55-year-old woman that was successfully treated by complete surgical excision.

Infrared studies of the α-crystalline form of polycaprolactam (nylon 6) have confirmed the assignment of the 1288 and 1210-cm−1 bands to a unique fold conformation. The γ-crystalline phase has a band at 1212 cm−1 which overlaps the 1210-cm−1 fold band in samples containing both α and γ phases. The 1288-cm−1 band was, therefore, used to monitor regular fold content. No unique fold bands were detected in the γ form. Irregular folds present in solution-grown crystals regularize to the unique fold conformation upon annealing. Crystals which originally exhibit slight differences in regular folding as a result of different crystallization history have similar amounts of regular folds upon annealing at 220°C. Crystals grown from solutions of very dilute concentrations of polymer have different amounts of regular folding. The annealing behavior of crystals prepared from two different solution concentrations reflect the processes of regularization and long period increase.