27 research outputs found
Azo Dyes, Their Environmental Effects, and Defining a Strategy for Their Biodegradation and Detoxification
Intenzivan industrijski razvoj popraćen je sve većom kompleksnošću sastava otpadnih voda, što u smislu učinkovite zaštite okoliša i održivog razvoja nalaže potrebu pospješivanja kvalitete postojećih te uvođenjem novih postupaka obrade otpadnih voda, kao iznimno važnog čimbenika u interakciji čovjeka i okoliša. Posebnu znanstveno-tehnološku pozornost zahtijevaju novosintetizirani ksenobiotici, poput azo-boja, koji su u prirodi veoma teško razgradivi. Azo-boje podložne su bioakumulaciji, a zbog alergijskih, kancerogenih, mutagenih i teratogenih svojstava nerijetko su prijetnja zdravlju ljudi i očuvanju okoliša. Primjenu fi zikalnokemijskih
metoda za uklanjanje azo-boja iz otpadnih voda često ograničavaju visoke cijene, potrebe za odlaganjem nastalog štetnog mulja ili nastanak toksičnih sastojaka razgradnje. Biotehnološki postupci su,
zbog mogućnosti ekonomične provedbe i postizanja potpune biorazgradnje, a time i detoksifi kacije, sve zastupljeniji u obradi svih vrsta otpadnih voda, pa tako i onih koje sadržavaju azo-boje.Intense industrial development has been accompanied by the production of wastewaters of very complex content, which pose a serious hazard to the environment, put at risk sustainable development, and call for new treatment technologies that would more effectively address the issue. One particular challenge in terms of science and technology is how to biodegrade xenobiotics such as azo dyes, which practically do not degrade under natural environmental conditions. These compounds tend to bioaccumulate in the environment, and have allergenic, carcinogenic, mutagenic, and teratogenic properties for humans. Removal of azo dyes from effl uents is mostly based on physical-chemical methods. These methods are often very costly and limited, as they accumulate concentrated sludge, which also poses a significant secondary disposal problem, or produce toxic end-products. Biotechnological approach may offer alternative, lowcost biological treatment systems that can completely biodegrade and detoxify even the hard-to-biodegrade azo dyes
Source Anonymization Through Counter Forensics
A lot of photographers and human rights advocates need to hide their identity while sharing their images on the internet. Hence, source–anonymization of digital images has become a critical issue in the present digital age. The art and science of impeding and misleading forensic analysis of the digital image is known as Counter Forensics. The current literature contains a number of digital forensic techniques for “source–identification” of digital images, one of the most efficient of them being Photo–Response Non–Uniformity (PRNU) sensor noise pattern based source detection. PRNU noise pattern being unique to every digital camera, such techniques prove to be a highly robust way of source–identification. In this work, first, we propose a counter–forensic technique to mislead this PRNU sensor noise pattern based source–identification, by using a median filter and Modified hybrid median filter to suppress PRNU noise in an image, iteratively. Our experimental results prove that the proposed methods achieve a considerably higher degree of source anonymity, measured as an inverse of Peak–to–Correlation Energy (PCE) ratio, as compared to the state–of–the–art.
Next, we deliver an attack on digital images, where we completely remove the traces of sensor pattern noises of their source devices, so as to deceive forensic investigations and again, we substitute the sensor pattern of a given image with that of a different (wrong) source device, such that it now appears to the forensic analyst, that the image was produced by device B, whereas originally it was produced by A. Our experimental results prove that high correlation is achieved between a tampered image and a wrong device, suggesting considerably high degree of anonymity, hence misleading forensics investigation
Exploring the rearrangement of sensory intelligence in proteobacteria: insight of Pho regulon
Pho regulon is a highly evolved and conserved mechanism across the microbes to fulfil their phosphate need. In this study,
52 proteobacteria genomes were analyzed for the presence of phosphorus acquisition genes, their pattern of arrangement
and copy numbers. The diverse genetic architecture of the Pho regulon genes indicates the evolutionary challenge of nutrient
limitation, particularly phosphorus, faced by bacteria in their environment. The incongruence between the Pho regulon
proteins phylogeny and species phylogeny along with the presence of additional copies of pstS and pstB genes, having cross
similarity with other genera, suggest the possibility of horizontal gene transfer event. The substitution rate analysis and
multiple sequence alignment of the Pho regulon proteins were analyzed to gain additional insight into the evolution of the
Pho regulon system. This comprehensive study confirms that genes perform the regulatory function (phoBR) were vertically
inherited, whereas interestingly, genes whose product involved in direct interaction with the environment (pstS) acquired by
horizontal gene transfer. The substantial amino acid substitutions in PstS most likely contribute to the successful adaptation of
bacteria in different ecological condition dealing with different phosphorus availability. The findings decipher the intelligence
of the bacteria which enable them to carry out the targeted alteration of genes to cope up with the environmental condition
Insights in Waste Management Bioprocesses Using Genomic Tools
Microbial capacities drive waste stabilization and resource recovery in environmental
friendly processes. Depending on the composition of waste, a stress-mediated selection
process ensures a scenario that generates a specific enrichment of microbial community.
These communities dynamically change over a period of time while keeping
the performance through the required utilization capacities. Depending on the environmental
conditions, these communities select the appropriate partners so as to
maintain the desired functional capacities. However, the complexities of these organizations
are difficult to study. Individual member ratios and sharing of genetic intelligence
collectively decide the enrichment and survival of these communities. The
next-generation sequencing options with the depth of structure and function analysis
have emerged as a tool that could provide the finer details of the underlying bioprocesses
associated and shared in environmental niches. These tools can help in identification
of the key biochemical events and monitoring of expression of associated
phenotypes that will support the operation and maintenance of waste management
systems. In this chapter, we link genomic tools with process optimization and/or management,
which could be applied for decision making and/or upscaling. This review
describes both, the aerobic and anaerobic, options of waste utilization process with
the microbial community functioning as flocs, granules, or biofilms. There are a number
of challenges involved in harnessing the microbial community intelligence with associated
functional plasticity for efficient extension of microbial capacities for resource
recycling and waste management. Mismanaged wastes could lead to undesired genotypes
such as antibiotic/multidrug-resistant microbes