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The present investigation explored two novel adsorbents, i.e., hydroxyapatite (HAP) and moringa-modified activated carbon (MMAC) from eggshell and moringa (Moringa oleifera) seeds, respectively, for the treatment of tannery effluents (TE). Particular emphasis was given to Cr(VI) adsorption when varying equilibration time, effluent pH, initial concentration of Cr(VI) and temperature. The adsorbents' characteristics suggested significant Cr(VI) accumulation onto the adsorbent's surface, whereas adsorption modelling recommended pseudo-second-order (PSO) and Langmuir models fitted well with the experimental data based on the regression coefficient (R2) values with minimum errors. The surface complexation model (SCM) indicated that speciation of Cr(VI) sorbed complexes formed an inner-sphere compound dominated by acidic pH, validated by pHpzc. The maximum adsorption capacities (qmax) of Cr(VI) were accounted to be 295 and 280 mg/g for HAP and MMAC, correspondingly. Interestingly, both adsorbents effectively removed other metallic ions; Fe, Pd, Cu and Zn removal was 85 %, while Cd, Ni, and Mn removal was 70 %. The Cr(VI) adsorption processes followed chemisorption mechanisms dominated by the surface complexation phenomenon. The performance of a 100 L packed-bed reactor was evaluated, and the breakthrough time of Cr(VI) adsorption for both adsorbents was 15 min. The adsorbents had splendid regeneration capacities and could be re-used numerous times. In essence, the present study concludes that both adsorbents are highly effective at removing Cr(VI) and other contaminants. The adsorbents are innovative and economical and can be one of the breakthrough feasible options for treating toxic contaminants in a large-scale TE.

Although its mechanism of action, particularly under wetland condition, is not clearly understood, vermicompost, a good source of humus and plant nutrients, has been used as organic manure in many parts of the world in order to increase crop production. Here, an anaerobic incubation study and a field study were conducted to observe the nutrient release pattern from vermicompost and its influence on performance and nutrient uptake in wetland rice. Two contrasting soils, viz. highly weathered terrace soil and very young floodplain soil, were subjected to anaerobic incubation, while the field trial was conducted in the terrace soil with control (no amendments), mineral fertilizer, vermicompost (10 t ha−1) + mineral fertilizer, cow dung (10 t ha−1) + mineral fertilizer, vermicompost (20 t ha−1) + mineral fertilizer and vermicompost (local farmer’s practice) + mineral fertilizer treatments. Results showed that there were significant increases in nitrogen (N) and phosphorous (P) release in floodplain soil but not in terrace soil, suggesting that nutrient release from vermicompost is soil-dependent. The performance of Boro rice in terms of yield and yield attributes improved significantly in the case of the integrated application of vermicompost with mineral fertilizer. Specifically, combined application of mineral nutrients and vermicompost (10 t ha−1) significantly increased grain yield by 25% compared to the control treatment. We believe that this occurred due to an improvement in supply and subsequent uptake of nutrients, especially N and P. Altogether, our results suggest that vermicompost could increase crop performance under field conditions, and, although these effects may not be significant in short-term incubation studies, they may be even larger in floodplain soil.

Bacterial degradation of sinking diatom aggregates is key for the availability of organic matter in the deep-ocean. Yet, little is known about the impact of aggregate colonization by different bacterial taxa on organic carbon and nutrient cycling within aggregates. Here, we tracked the carbon (C) and nitrogen (N) transfer from the diatom Leptocylindrus danicus to different environmental bacterial groups using a combination of 13C and 15N isotope incubation (incubated for 72 h), CARD-FISH and nanoSIMS single-cell analysis. Pseudoalteromonas bacterial group was the first colonizing diatom-aggregates, succeeded by the Alteromonas group. Within aggregates, diatom-attached bacteria were considerably more enriched in 13C and 15N than non-attached bacteria. Isotopic mass balance budget indicates that both groups showed comparable levels of diatom C in their biomass, accounting for 19 ± 7% and 15 ± 11%, respectively. In contrast to C, bacteria of the Alteromonas groups showed significantly higher levels of N derived from diatoms (77 ± 28%) than Pseudoalteromonas (47 ± 17%), suggesting a competitive advantage for Alteromonas in the N-limiting environments of the deep-sea. Our results imply that bacterial succession within diatom aggregates may largely impact taxa-specific C and N uptake, which may have important consequences for the quantity and quality of organic matter exported to the deep ocean.

Background A key component of cancer research is the availability of clinical samples with appropriately annotated clinical data. Biobanks facilitate research by collecting/storing various types of clinical samples for research. Brain Cancer Biobanking Australia (BCBA) was established to facilitate the networking of brain cancer biobanking operations Australia-wide. Maximizing biospecimen utility in a networked biobanking environment requires the standardization of procedures and data across different sites. The aim of this research was to scope and develop a recommended clinical annotation dataset both for pediatric and adult brain cancer biobanks. Methods A multidisciplinary working group consisting of members from the BCBA Consortium was established to develop clinical dataset recommendations for brain cancer biobanks. A literature search was undertaken to identify any published clinical dataset recommendations for brain cancer biobanks. An audit of data items collected and stored by BCBA member biobanks was also conducted to survey current clinical data collection practices across the BCBA network. Results BCBA has developed a clinical annotation dataset recommendation for pediatric and adult brain cancer biobanks. The clinical dataset recommendation has 5 clinical data categories: demographic, clinical and radiological diagnosis and surgery, neuropathological diagnosis, patient treatment, and patient follow-up. The data fields have been categorized into 1 of 3 tiers; essential, preferred, and comprehensive. This enables biobanks and researchers to prioritize appropriately where resources are limited. Conclusion This dataset can be used to guide the integration of data from multiple existing biobanks for research studies and for planning prospective brain cancer biobanking activities.