Anaerobic co-digestion of sewage sludge with cellulose, protein, and lipids: Role of rheology and digestibility

Rheology is known to have an impact on the performance of digesters, but the effect of additional substrates (co-digestion) is poorly understood. The main objective of this study was to investigate the effects of the addition of cellulose, protein and lipids to substrates on the rheological behaviour and biogas production of the mixture of primary sludge (PS) and waste-activated sludge (WAS) in a batch system. A mixture of PS and WAS to form the main substrate was anaerobically co-digested with different types of organic matter (cellulose, protein and lipids) as co-substrates at different co-substrate to main substrate ratios of 2-8 (wt%) under mesophilic conditions and below ammonia inhibition levels. Yield stress (τ_y) and the flow consistency index (k) of the combined feed in the case of cellulose and protein were significantly dependent on the amount of co-substrate added, while there was an insignificant impact on these properties when lipids were added. Cellulose significantly increased τ_y and k in the feed, which resulted in poor fluidity and the improper homogenisation of the digester content, and consequently decreased the biogas yield. In contrast, the biogas yield was improved through the addition of 2% to 6% protein despite an increase in τ_y and k of the feed, but the methane yield decreased at 7% and 8% levels of protein concentration. This observation indicates that the threshold for τ_y and k of the digester media depends on the organic nature and digestibility of the substrate. There was no significant impact on the flow properties of the initial mixture when lipids were added, and their addition increased the biogas yield. A first-order kinetic reaction model was used for predicting the yield of methane from these digesters. The rate constant values revealed an increasing trend, with the highest for protein then lipids then cellulose.

The ORNATE India Project: United Kingdom-India Research Collaboration to tackle visual impairment due to diabetic retinopathy

INTRODUCTION

The ORNATE India project is funded by the UK Research and Innovation (UKRI) through the Global Challenges Research Fund. The aim is to build research capacity and capability in India and the UK to tackle global burden of diabetes-related visual impairment. As there are over 77 million people with diabetes in India, it is challenging to screen every person with diabetes annually for sight-threatening diabetic retinopathy (DR). Therefore, alternate safe approaches need to be developed so that those at-risk of visual impairment due to DR is identified promptly and treated.

METHODS

The project team utilised diverse global health strategies and research methods to co-design work packages to build research capacity and capability to ensure effective, affordable and efficient DR services are made available for the population. The strategies and methods employed included health system strengthening; implementation science; establishing care pathways; co-designing collaborative studies on affordable technologies, developing quality standards and guidelines to decrease variations in care; economic analysis; risk modelling and stratification. Five integrated work packages have been developed to deal with all aspects of DR care. These included implementation of a DR screening programme in the public health system in a district in Kerala, evaluating regional prevalence of diabetes and DR and assessing ideal tests for holistic screening for diabetes and its complications in 20 areas in India, utilising artificial intelligence on retinal images to facilitate DR screening, exploring biomarker and biosensor research to detect people at risk of diabetes complications, estimating cost of blindness in India and risk modelling to develop risk-based screening models for diabetes and its complications. A large collaborative network will be formed to propagate research, promote shared learning and bilateral exchanges between high- and middle-income countries to tackle diabetes-related blindness.

Immunohistochemical detection of naturally occurring porcine Sapelovirus infection in Indian pigs

We investigated immunohistochemical detection of porcine Sapelovirus (PSV) in naturally infected pigs of different ages. Forty-nine fecal samples, intestinal contents and other tissue samples from dead pigs were screened in previous study using reverse transcription polymerase chain reaction (RT-PCR) for PSV infection. Eight animals were positive for PSV based on RT-PCR examination. Gross lesions were recorded mainly in the large and small intestines. Microscopic examination of intestines showed severe enteritis. Tissue sections of all organs from PSV positive animals were immunostained using hyperimmune serum raised in rats against PSV that had been grown in a BHK-21 cell line. Staining of PSV was found only in the large and small intestines.

Impact of rheological properties of substrate on anaerobic digestion and digestate dewaterability: New insights through rheological and physico-chemical interaction

Mesophilic batch anaerobic digesters fed by different substrates were set up to identify the role of substrate rheology in anaerobic digestion performance while operating below the toxic level. Five substrates of different rheological behaviour but at the same amount of organic matters were prepared by addition of different amount of an inert material (0, 0.03, 0.07, 0.11, and 0.20 g) per g of waste activated sludge (WAS). To gain a comprehensive insight, the interactive relationship between substrate rheology, physico-chemical properties and biogas production as well as digestate dewaterability was investigated. The results proved that better access of microorganisms to organic matters improved the digester performance and led to 19.29% and 12.5% increase in biogas yield and VS removal efficiency, respectively. Moreover, the statistical analysis showed that consistency index and loss modulus of sludge could be employed as promising indications for biogas yield while yield stress could predict dewaterability of digestate as far as the other physico-chemical properties remained unchanged. During digestion measurement of consistency index and loss modulus of digestate could be performed as a reliable tool to monitor biogas production.

Recommended electron-impact excitation and ionization cross sections for Be I

Analytic fits to the recommended electron-impact excitation and ionization cross sections for Be I are presented. The lowest 19 terms of configurations 2snl (n ≤ 4) and 2p ² terms below the first ionization limit are considered. The fits are based on the accurate calculations with the convergent close coupling (CCC) method as well as the B-spline R-matrix (BSR) approach. The fitted cross sections provide rate coefficients that are believed to approximate the original data within 10% with very few exceptions. The oscillator strengths for the dipole-allowed transitions between all the considered states are calculated with the relativistic multi-configuration Dirac-Hartree-Fock (MCDHF) approach and compared with the CCC and BSR results. This comparison shows a very good agreement except for a handful of cases with likely strong cancellations.

Microenvironmental heterogeneity caused by anthropogenic LULC foster lower plant assemblages in the riparian habitats of lentic systems in tropical floodplains

Anthropogenic land use and land cover (LULC) create a heterogeneous environment in the floodplains. This heterogeneity may be governing plant species assemblages, diversity, and dominance patterns in the riparian habitats of the lentic systems in tropical floodplains. We tested this hypothesis in the floodplains of Barak river basin in northeast India following standard methods of plant and soil sampling/analysis and multivariate statistical tools. Plant community studies in the riparian habitats of the selected lentic systems were done at monthly intervals for a period of one year, while soil sampling and analysis were done at bimonthly intervals. Standard data visualization plots and canonical correspondence analysis (CCA) were used to assess spatiotemporal variations in species richness and diversity, environmental heterogeneity, and species-environment association. The study revealed that anthropogenic land use and land cover significantly affects species assemblage, diversity, and dominance in the riparian habitats. The variations in vegetation structure and composition with respect to the adjoining land use type plausibly have implications on the structure and functioning of the lentic systems. Thus, the study recommends that a holistic approach involving the riparian areas is required for effective management of tropical floodplains.

Major venom proteins of the fire ant Solenopsis invicta: insights into possible pheromone-binding function from mass spectrometric analysis

Proteins in the venom of the fire ant Solenopsis invicta have been suggested to function in pheromone binding. Venom from queens and workers contains different isoforms of these proteins, consistent with the differing pheromones they secrete, but questions remain about the venom protein composition and glandular source. We found that the queen venom contains a previously uncharacterized pheromone-binding protein paralogue known as Sol i 2X1. Using imaging mass spectrometry, we located the main venom proteins in the poison sac, implying that pheromones might have to compete with venom alkaloids for binding. Using the known structure of the worker venom protein Sol i 2w, we generated three-dimensional homology models of the worker venom protein Sol i 4.02, and of the two main venom proteins in queens and female alates, Sol i 2q and Sol i 2X1. Surprisingly, the models show that the proteins have relatively small internal hydrophobic binding pockets that are blocked by about 10 amino acids of the C-terminal region. For these proteins to function as carriers of hydrophobic ligands, a conformational change would be required to displace the C-terminal region, somewhat like the mechanism known to occur in the silk moth pheromone-binding protein.

Continuous Hyperfractionated Accelerated Radiotherapy (CHART) for Non-small Cell Lung Cancer (NSCLC): 7 Years' Experience From Nine UK Centres

AIM

Continuous hyperfractionated accelerated radiotherapy (CHART) remains an option to treat non-small cell lung cancer (NSCLC; NICE, 2011). We have previously published treatment outcomes from 1998-2003 across five UK centres. Here we update the UK CHART experience, reporting outcomes and toxicities for patients treated between 2003 and 2009.

MATERIALS AND METHODS

UK CHART centres were invited to participate in a retrospective data analysis of NSCLC patients treated with CHART from 2003 to 2009. Nine (of 14) centres were able to submit their data into a standard database. The Kaplan-Meier method estimated survival and the Log-rank test analysed the significance.

RESULTS

In total, 849 patients had CHART treatment, with a median age of 71 years (range 31-91), 534 (63%) were men, 55% had undergone positron emission tomography-computed tomography (PET-CT) and 26% had prior chemotherapy; 839 (99%) patients received all the prescribed treatment. The median overall survival was 22 months with 2 and 3 year survival of 47% and 32%, respectively. Statistically significant differences in survival were noted for stage IA versus IB (33.2 months versus 25 months; P = 0.032) and IIIA versus IIIB (20 months versus 16 months; P = 0.018). Response at 3 months and outcomes were significantly linked; complete response showing survival of 34 months against 19 months, 15 months and 8 months for partial response, stable and progressive disease, respectively (P < 0.001). Age, gender, performance status, prior chemotherapy and PET-CT did not affect the survival outcomes. Treatment was well tolerated with <5% reporting ≥grade 3 toxicity.

CONCLUSION

In routine practice, CHART results for NSCLC remain encouraging and we have been able to show an improvement in survival compared with the original trial cohort. We have confirmed that CHART remains deliverable with low toxicity rates and we are taking a dose-escalated CHART regimen forward in a randomised phase II study of sequential chemoradiotherapy against other accelerated dose-escalated schedules.

Characterization and compositional analysis of highly acidic karanja oil and its potential feedstock for enzymatic synthesis of biodiesel

In the present study, we focused on the synthesis of biodiesel fromPseudomonas cepacia, crude karanja oil by the process of enzymatic transesterification using bio-support materials, such as lipase immobilized on polyvinyl alcohol/AlgNa.