Assessment of NORMs (238U, 232Th, 40K) and radiation hazard indices in Beldih apatite mine region of Purulia district, West Bengal, India.

The radiation arising from naturally occurring radioactive materials (NORMs) is the foremost contributor to the collective dose received by the global population. The present study aims to measure the natural background radiation level and the associated gamma radiation dose in air in the Beldih apatite mine region of Purulia district, India. This study is primarily focused on the determination of 238U, 232Th and 40K activities in the sub-surface soil of the study area. The measurements were carried out using a High Purity Germanium (HPGe) detector-based gamma-ray spectrometer with a relative efficiency of 80%. To achieve uniformity in exposure estimations, radium equivalent activity has been calculated. Additionally, the internal hazard index, external hazard index, radioactivity level index and gamma dose rates have been evaluated to estimate the radiation hazard levels in the study area. The comparison of obtained concentrations and hazard indices with global data (UNSCEAR. (2008). Sources, effects and risks of ionizing radiation. United nations scientific committee on the effects of atomic radiation (report to the general assembly, with Annexes).) suggests that this region lies in a relatively high background radiation zone.

Spectral characterization and severity assessment of rice blast disease using univariate and multivariate models.

Rice is the staple food of more than half of the population of the world and India as well. One of the major constraints in rice production is frequent occurrence of pests and diseases and one of them is rice blast which often causes yield loss varying from 10 to 30%. Conventional approaches for disease assessment are time-consuming, expensive, and not real-time; alternately, sensor-based approach is rapid, non-invasive and can be scaled up in large areas with minimum time and effort.  In the present study, hyperspectral remote sensing for the characterization and severity assessment of rice blast disease was exploited. Field experiments were conducted with 20 genotypes of rice having sensitive and resistant cultivars grown under upland and lowland conditions at Almora, Uttarakhand, India. The severity of the rice blast was graded from 0 to 9 in accordance to International Rice Research Institute (IRRI).  Spectral observations in field were taken using a hand-held portable spectroradiometer in range of 350-2500 nm followed by spectral discrimination of different disease severity levels using Jeffires-Matusita (J-M) distance. Then, evaluation of 26 existing spectral indices (r≥0.8) was done corresponding to blast severity levels and linear regression prediction models were also developed. Further, the proposed ratio blast index (RBI) and normalized difference blast index (NDBI) were developed using all possible combinations of their correlations with severity level followed by their quantification to identify the best indices. Thereafter, multivariate models like support vector machine regression (SVM), partial least squares (PLS), random forest (RF), and multivariate adaptive regression spline (MARS) were also used to estimate blast severity. Jeffires-Matusita distance was separating almost all severity levels having values >1.92 except levels 4 and 5. The 26 prediction models were effective at predicting blast severity with R2 values from 0.48 to 0.85. The best developed spectral indices for rice blast were RBI (R1148, R1301) and NDBI (R1148, R1301) with R2 of 0.85 and 0.86, respectively. Among multivariate models, SVM was the best model with calibration R2=0.99; validation R2=0.94, RMSE=0.7, and RPD=4.10. The methodology developed paves way for early detection and large-scale monitoring and mapping using satellite remote sensors at farmers' fields for developing better disease management options.

Non-invasive assessment of telomere maintenance mechanisms in brain tumors.

Telomere maintenance is a universal hallmark of cancer. Most tumors including low-grade oligodendrogliomas use telomerase reverse transcriptase (TERT) expression for telomere maintenance while astrocytomas use the alternative lengthening of telomeres (ALT) pathway. Although TERT and ALT are hallmarks of tumor proliferation and attractive therapeutic targets, translational methods of imaging TERT and ALT are lacking. Here we show that TERT and ALT are associated with unique 1H-magnetic resonance spectroscopy (MRS)-detectable metabolic signatures in genetically-engineered and patient-derived glioma models and patient biopsies. Importantly, we have leveraged this information to mechanistically validate hyperpolarized [1-13C]-alanine flux to pyruvate as an imaging biomarker of ALT status and hyperpolarized [1-13C]-alanine flux to lactate as an imaging biomarker of TERT status in low-grade gliomas. Collectively, we have identified metabolic biomarkers of TERT and ALT status that provide a way of integrating critical oncogenic information into non-invasive imaging modalities that can improve tumor diagnosis and treatment response monitoring.

Assessment of polycyclic aromatic hydrocarbon contamination in the Sundarbans, the world's largest tidal mangrove forest and indigenous microbial mixed biofilm-based removal of the contaminants.

The distribution of polycyclic aromatic hydrocarbons (PAHs) in the surface water and sediments in five regions of the Indian Sundarbans was assessed. The capability of microbial biofilm communities to sequester PAHs in a biofilm-promoting vessel was evaluated. The total PAH concentration of water and sediments ranged from undetectable to 125 ng ml-1 and 4880 to 2 × 104 ng g-1 dry weight respectively. The total PAHs concentration of sediments exceeded the Effects Range-Low value and the recommended Effects Range-Median values, implying the PAHs might adversely affect the biota of the Sundarbans. Pyrogenic and petrogenic sources of PAH contamination were identified in most of the sampling sites. Indigenous biofilms were cultivated in a patented biofilm-promoting culture vessel containing liquid media spiked with 16 priority PAHs. Biofilm-mediated 97-100% removal efficiency of 16 PAHs was attained in all media. There was no significant difference between the mean residual PAH from the liquid media collected from hydrophobic and hydrophilic flasks. Residual amounts of acenaphthene (Ace), anthracene (Ant), benzo(b)fluoranthene [B(b)F], benzo(a)pyrene [B(a)P] and benzo(g,h,i)perylene [B(g,h,i)P] showed differences when cultivated in hydrophobic and hydrophilic flasks. The mean residual amounts of total PAHs extracted from biofilm biomasses were variable. A biofilm obtained from a specific sampling site cultured in the hydrophobic flask showed higher PAH sequestration when compared to the removal attained in the hydrophilic flask. Relative abundances of different microbial communities in PAH-sequestering biofilms revealed bacterial phyla including Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Chloroflexi and Planctomycetes as well as members of Ascomycota phylum of fungi. The dominance of Candida tropicalis, Clostridium butyricum, Sphingobacterium multivorum and Paecilomyces fulvus were established.

Integration of poly-3-(hydroxybutyrate-co-hydroxyvalerate) production by Haloferax mediterranei through utilization of stillage from rice-based ethanol manufacture in India and its techno-economic analysis.

Haloferax mediterranei has potential for economical industrial-scale production of polyhydroxyalkanoate (PHA) as it can utilize cheap carbon sources, has capacity for nonsterile cultivation and allows simple product recovery. Molasses-based Indian distilleries are converting themselves to cereal-based distilleries. Waste stillage (14 l) of rice-based ethanol industry was used for the production of PHA by H. mediterranei in the simple plug-flow reactor configuration of the activated sludge process. Cells utilized stillage and accumulated 63 ± 3 % PHA of dry cell weight and produced 13.12 ± 0.05 g PHA/l. The product yield coefficient was 0.27 while 0.14 g/l h volumetric productivity was reached. Simultaneous lowering of 5-day biochemical oxygen demand and chemical oxygen demand values of stillage by 82 % was attained. The biopolymer was characterized as poly-3-(hydroxybutyrate-co-17.9 mol%-hydroxyvalerate) (PHBV). Directional properties of decanoic acid jointly with temperature-dependent water solubility in decanoic acid were employed for two-step desalination of the spent stillage medium in a cylindrical baffled-tank with an immersed heater and a stirrer holding axial and radial impellers. 99.3 % of the medium salts were recovered and re-used for PHA production. The cost of PHBV was estimated as US$2.05/kg when the annual production was simulated as 1890 tons. Desalination contributed maximally to the overall cost. Technology and cost-analysis demonstrate that PHA production integrated with ethanol manufacture is feasible in India. This study could be the basis for construction of a pilot plant.