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In this work, two different microfluidic paper-based analytical devices (μPADs) were developed for the quantification of nitrite and nitrate in human saliva samples, in order to aid in the diagnosis of some diseases and health conditions associated with these ions. The development of these nitrite and nitrate μPADs involved several studies to optimize their design and construction, including an interference assessment and stability studies. These μPADs allowed a nitrite determination in a range of 5–250 μM with limits of detection and quantification of 0.05 μM and 0.17 μM, respectively, and a nitrate determination in the range 0.2–1.2 mM with limits of detection and quantification of 0.08 mM and 0.27 mM, respectively. As for the stability, both of the μPADs were stable when stored in vacuum at 4 °C (the nitrite μPAD for at least 60 days and the nitrate μPAD for at least of 14 days) and, after the sample placement, the nitrite and nitrate μPADs could be scanned within the first 4 and 2 h, respectively. The nitrite μPAD measurements were compared with the ones obtained from the standard colorimetric method and there were no statistically significant differences between these two methods. To evaluate the accuracy of nitrate μPAD measurements, 4 certified water samples were used and recovery studies using saliva samples were performed.

Ninhydrin was implemented as the primary police method of developing latent fingermarks on paper, cardboard and some other porous surfaces from the late 1960s. Some researchers have used individual amino acids, or mixtures of amino acids, as a method of testing the effectiveness of reagent formulations. It was not however known whether simple mixtures of amino acids could effectively emulate latent fingermarks in reactions with reagents such as ninhydrin. The first part of this study compared the effects of ninhydrin fingermark treatments used internationally in various police laboratories on test targets created by inkjet printing graduated concentrations of a representative mixture of amino acids in a series of blocks on paper. Variations in intensity of development were observed between laboratories which used various formulations and heat and humidity post treatment protocols. In a further trial in 2015 several participants in the International Fingerprint Research Group (IFRG) meeting processed test targets in their own laboratories and submitted them for measurement. Again, variation in developed intensity was observed. The depletion of the activity of ninhydrin solutions during use was also investigated in early evaluations of the test targets. An established fingerprint laboratory then processed a number of samples from a batch of targets to examine batch consistency. This was followed by designing a new test target which enabled comparisons between the developed intensity of printed test target blocks alongside depletion series of split, natural donor fingermarks. A panel of 20 donors provided depletion fingermarks and four ninhydrin formulations and treatment protocols were used. The developed test target blocks were scanned, intensity of development measured, and the results compared with the fingermark development which was evaluated by three assessors using two types of scale. Good correlation between the intensity of the developed test targets and latent fingermark quality and intensity scores was observed with the four ninhydrin treatment protocols, including some which used deliberately downgraded ninhydrin concentrations. This type of evaluation was carried out a second time to investigate modified heat and humidity protocols. The use of such test targets for routine reagent quality control and process verification would appear to be far more accurate and reliable than the use of small numbers of donor fingermarks. It is not clear why the different ninhydrin formulations investigated in the latter part of the work have very different optimum post treatment heating regimes.

We studied the avoidance behaviour of the earthworm Eisenia fetida towards Cd, Cu, and Zn, trace elements (TEs) tested as chloride, nitrate and sulphate salts. Sub adults were exposed individually using dual-cell chambers at 20+2°C in the dark. Recordings were realised at different dates from 2h to 32h. We used filter paper and extruded water agar gel as exposure media to evaluate the contribution of the dermal and the digestive exposure routes on the avoidance reactions. Exposures to Cu or Cd (10mgmetal ionL(-1)) resulted in highly significant avoidance reactions through the exposure duration. Worms avoided Zn poorly and reactions towards Zn salts varied along the exposure. Worm sensitivity towards TEs differed between salts and this could result from differential toxicity or accessibility of these TE salts to earthworms. The anion in itself was not the determinant of the avoidance reactions since exposures to similar concentrations of these anions using calcium salts did not result in significant avoidance worm behaviour. Avoidance responses towards TEs were higher in the case of water agar exposures than in filter paper exposures. Thus, dermal contacts with TE solutions would elicit worm avoidance but signals from receptors located inside the digestive tract could reinforce this behaviour. The use of extruded water agar gels as the substrate allows checking the real sensitivity of earthworm species towards TEs since the TE concentrations leading to significant avoidance reactions were below those reported in the literature when using TE-spiked soils.

The seasonal physico-chemical and microbial quality of Gola river water has been analyzed after confluence of pulp paper mill waste. The study revealed that it has enhanced 20-30 times pollution load of BOD, COD, TDS, TSS, sulphate, chloride, sodium, nitrate, potassium, lignin and phenol after mixing of pulp paper mill waste with river water in all season. Further, it induced the bacterial growth by increasing most probable number value of E. coli was 1.57 x 10(4), 1.6 x 10(4), 1.37 x 10(4) and SPC count was 1.68 x 10(4), 1.64 x 10(4), 1.67 x 10(4)/100 ml during summer, monsoon, winter respectively. While the most probable number value in river water before mixing of pulp paper mill waste was 1.4 x 10(2), 1.82 x 10(2), 1.5 x 10(2) and SPC count was 2.8 x 10(3), 2.89 x 10(3), 2.78 x 10(3)/100 ml during summer, monsoon and winter respectively. This indicated from 88-114 fold increase in most probable number value of E. coli and 56.55-60.0 times increase in SPC count of river water after mixing of effluent in summer, monsoon and winter. Moreover, the most probable number value in effluent itself before mixing was 3.4 x 10(2), 3.3 x 10(2), 2.8 x 10(2) and SPC count was 6 x 10(4), 6.5 x 10(4), 6 x 10(4)/100 ml during summer, monsoon, winter, respectively. Furthermore, it was revealed that the seasonal variation also regulated the bacterial population dynamics as per the physico-chemical quality, in which E. coli was found highest at the rate of (5.9 x 10(4)), E. aerogenes (5.3 x 10(4)), P. aeruginosa (1.3 x 10(4)), S. aureus (3.2 x 10(3)), K. pneumoniae (2.6 x 10(4)), Enteritidis (1.1 x 10(4)) on monsoon season and V. cholerae (7.4 x 10(2)), V. vulnificus (9.2 x 10(2))/100 ml in river water when contaminated with pulp paper mill waste in monsoon season. Thus, the monsoon season showed presence of FC and TC indicated the thermo-tolerant and disease causing group of bacterial population in effluent and its sequence was observed as monsoon>summer>winter. This indicated the growth of many pathogenic and non-pathogenic bacteria for health hazards with contamination of pulp paper waste in aquatic ecosystem within the vicinity of pulp paper mill industry.

An offender who has recently handled bulk explosives would be expected to deposit latent fingermarks that are contaminated with explosive residues. However, fingermark detection techniques need to be applied in order for these fingermarks to be detected and recorded. Little information is available in terms of how routine fingermark detection methods impact on the subsequent recovery and analysis of any explosive residues that may be present. If an identifiable fingermark is obtained and that fingermark is found to be contaminated with a particular explosive then that may be crucial evidence in a criminal investigation (including acts of terrorism involving improvised explosive devices). The principal aims of this project were to investigate: (i) the typical quantities of explosive material deposited in fingermarks by someone who has recently handled bulk explosives; and (ii) the effects of routine fingermark detection methods on the subsequent recovery and analysis of explosive residues in such fingermarks. Four common substrates were studied: paper, glass, plastic (polyethylene plastic bags), and metal (aluminium foil). The target explosive compounds were 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), as well as chlorate and nitrate ions. Recommendations are provided in terms of the application of fingermark detection methods on surfaces that may contain explosive residues.

Denitrification is applied in the tertiary treatment of wastewater to reduce nitrogen pollution. Fluorescence in situ hybridization (FISH), catalyzed reporter deposition (CARD)-FISH, cloning, and scanning electron microscopy (SEM) were applied to follow the evolution of the microbial composition and structure of granular sludge in chemolithotrophic denitrifying bioreactors fed with nitrate and thiosulfate. FISH oligonucleotide probes for the chemolitoautotrophic denitrifiers Thiobacillus denitrificans and Thiomicrospira denitrificans were designed and their utility tested. CARD-FISH and cloning data showed that bacterial diversity in the biofilms changed during the reactor operation. Chemoorganotrophic fermentative Gram-positive strains in the phyla, Actinobacteria and Firmicutes, were dominant in the methanogenic inoculum, both in terms of biodiversity and in number. Other significant phyla were Bacteroidetes and Chloroflexi. After 6 months of operation, Proteobacteria became dominant (83% of the clones). The diversity of Gram-positive bacteria was partially maintained although their abundance decreased notably. After 110 d of operation, the abundance of Tb. denitrificans cells increased considerably, from 1% to 35% of total DAPI-stained cells and from no isolated clones to 15% of the total clones. Tm. denitrificans only represented a minor fraction of the microorganisms in the sludge (1-4% of the DAPI-stained cells). These findings confirm that Tb. denitrificans was the dominant chemolitoautotrophic denitrifying microorganism in the bioreactors. The Archaeal diversity remained almost unchanged and it was represented mostly by Methanosaeta soehngenii. SEM results indicated a considerable loss in the integrity of the sludge granules during the operation, with risk of sludge buoyancy.

This study concerned the anaerobic treatment of five different industrial wastewaters with a diverse and complex chemical composition. The kinetics of biotransformation of this wastewater at different chemical oxygen demand (COD) were studied in a batch reactor. Wastewater from an amino acid producing industry (Fermex) and from a tank that received several types of wastewaters (collector) contained 0.83 g l(-1) and 0.085 g l(-1) sulfate, respectively. During the study period of 20 days, methane formation was observed in all types of wastewaters. Studies on COD biodegradation showed the reaction velocity was higher for Fermex wastewater and lower for collector wastewater, with values of 0.0022 h(-1) and 0.0011 h(-1), respectively. A lower methanogenic activity of 0.163 g CH4 day(-1) g(-1) volatile suspended solids (VSS) and 0.20 g CH4 day(-1) g(-1) VSS, respectively, was observed for paper producing and brewery wastewater. Adapted granular sludge showed the best biodegradation of COD during the 20-day period. The sulfate-reducing activity in pharmaceutical and collector wastewater was studied. A positive effect of sulfate-reducing activity on methanogenic activity was noted for both types of wastewaters, both of which contained sulfate ions. All reactions of methane generation for the tested industrial wastewaters were first-order. The results of this study suggest that the tested wastewaters are amenable to anaerobic treatment.

Nitration of pancreatic trypsin inhibitor with tetranitromethane affords a mono-and a disubstituted derivative which was shown by sequential analysis to contain nitrotyrosine in position 10 and in positions 10 and 21, respectively. Both retain full trypsin inhibitor activity. Measurements of optical rotatory dispersion in the 230 nm region indicate that the secondary structure of the protein is unaffected by nitration. The nitrated derivatives exhibit a conformation-dependent side-chain Cotton effect in the region of nitroaromatic absorption. No such Cotton effect is shown by a nitrotyrosine-containing pentadecapeptide isolated from the tryptic digest from the nitrated and oxidized inhibitor.