Excessive discharge of nutrients in waters induces pollution such as such as eutrophication. Conventional methods to treat waters are expensive. Alternatively, anaerobic ammonium oxidation, termed ...“anammox”, has been recently developped with benefits such as low sludge production, 50% less aeration demand, no external carbon supply, 60% less power consumption, and 90% reduction of greenhouse gas emissions. However, anammox is limited by long start-up periods due to the low growth rate of anammox bacteria. This issue can be solved by complete retention of biomass by reactor modification or by formation of anammox granules. This article reviews the mechanisms of anammox granulation and biogranulation models. We present factors involved in the granulation processes such as hydrodynamic shear force, extracellular polymeric substances, hydraulic retention time, seed sludge and bioreactors. We also discuss the interaction of proteins and polysaccharides in anammox granules.
Inadequate environmental sanitation in many cities is a major cause of diseases and is a drain on the economy by way of lost workdays, cost of treatment and cleanup activities. Municipal authorities ...and policymakers need to act fast to address this issue. Sustainable waste management provides a comprehensive inter-disciplinary framework for addressing the problems of managing urban solid waste, in the resource constrained developing countries where quality of such services are poor and costs are high often with no effective means of recovering them. Upgrading the coverage of waste management and services and increasing their efficiency is a precondition for improving the environmental quality of cities. This paper highlights the fact that the involvement and participation of all the stakeholders such as the waste generators, waste processors, formal and informal agencies, non-governmental organisations and financing institutions is a key factor for the sustainable waste management.
The formation of social attachments is a critical component of human relationships. Infants begin to bond to their caregivers from the moment of birth, and these social bonds continue to provide ...regulatory emotional functions throughout adulthood. It is difficult to examine the interactions between social experience and the biological origins of these complex behaviors because children undergo both brain development and accumulate social experience at the same time. We had a rare opportunity to examine children who were reared in extremely aberrant social environments where they were deprived of the kind of care-giving typical for our species. The present experiment in nature provides insight into the role of early experience on the brain systems underlying the development of emotional behavior. These data indicate that the vasopressin and oxytocin neuropeptide systems, which are critical in the establishment of social bonds and the regulation of emotional behaviors, are affected by early social experience. The results of this experiment suggest a potential mechanism whose atypical function may explain the pervasive social and emotional difficulties observed in many children who have experienced aberrant care-giving. The present findings are consistent with the view that there is a critical role for early experience in the development of the brain systems underlying basic aspects of human social behavior.
Sex differences in the brain are largely organized by a testicular hormone surge that occurs in males shortly after birth. Although this hormone surge is transient, sex differences in brain and ...behavior are lasting. Here we describe a sex difference in DNA methylation of the estrogen receptor-α (ERα) promoter region within the developing rat preoptic area, with males exhibiting more DNA methylation within the ERα promoter than females. More importantly, we report that simulating maternal grooming, a form of maternal interaction that is sexually dimorphic with males experiencing more than females during the neonatal period, effectively masculinizes female ERα promoter methylation and gene expression. This suggests natural variations in maternal care that are directed differentially at males vs. females can influence sex differences in the brain by creating sexually dimorphic DNA methylation patterns. We also find that the early estradiol exposure may contribute to sex differences in DNA methylation patterns. This suggests that early social interaction and estradiol exposure may converge at the genome to organize lasting sex differences in the brain via epigenetic differentiation.
Early estradiol exposure and somatosensory stimuli received during maternal care contribute to sex differences in estrogen receptor-α expression and promoter DNA methylation patterns within the developing offspring brain.
Responding to environmental, sustainability, business, and market factors, DuPont has commercialized a new polymer platform, Sorona®, based on 1,3-propanediol. The physical and chemical property ...advantages over other polymers are described. The diol component of this polymer, 1,3-propanediol, has been demonstrated to be manufacturable via biological (fermentation) process from corn sugar. The economic, environmental, and process/product quality advantages of bio-PDO over conventional diols are discussed.PUBLICATION ABSTRACT
This paper presents a study on the resource and environmental profile of leather for communicating to the consumers about the environmental burdens of leather products. The results indicate that ...significant environmental impacts were caused during the tanning and finishing of leather as well as the electricity production and transportation required in the life cycle. The use of fossil fuels in the production of energy has greater impact with increased emissions leading to about 15190
kg CO
2 equivalent of global warming and about 73
kg SO
2 equivalent of acidification while producing 100
m
2 of leather for shoe uppers. Further resource use of 174
kg of coal, 6.5
kg of fuel oil, 17.4
m
3 of water and 348
kg of chemicals of which about 204
kg are hazardous are consumed, and wastewater of about 17
m
3, BOD of 55
kg, COD of about 146
kg, TDS of 732
kg and solid waste of about 1445
kg are generated during the life cycle for the production of 100
m
2 of leather. The total solid waste generated is 1317
kg, out of which about 80% is biodegradable contributed by slaughtering, tanning and finishing stage, 14% is non-biodegradable contributed by tanning, finishing and electricity production stages and 6% is hazardous mainly from tanning and finishing stage of leather.
Reproduction depends on the establishment and maintenance of elevated GnRH neurosecretion. The elevation of primate GnRH release is accompanied by epigenetic changes. Specifically, cytosine residues ...within the GnRH gene promoter are actively demethylated, whereas GnRH mRNA levels and peptide release rise. Whether active DNA demethylation has an impact on GnRH neuron development and consequently reproductive function remains unknown. In this study, we investigated whether ten-eleven translocation (tet) enzymes, which initiate the process of active DNA demethylation, influence neuronal function and reproduction. We found that tet2 expression increases with age in the developing mouse preoptic area-hypothalamus and is substantially higher in a mature (GT1–7) than an immature (GN11) GnRH cell line. GnRH mRNA levels and mean GnRH peptide release elevated after overexpression of tet2 in GN11 cells, whereas CRISPR/cas9-mediated knockdown of tet2 in GT1–7 cells led to a significant decline in GnRH expression. Manipulations of tet2 expression altered tet2 genome binding and histone 3 lysine 4 trimethylation abundance at the GnRH promoter. Mice with selective disruption of tet2 in GnRH neurons (GnRH-specific tet2 knockout mice) exhibited no sign of altered pubertal timing in either sex, although plasma LH levels were significantly lower, and fecundity was altered specifically in adult male GnRH-specific tet2 knockout animals, indicating that tet2 may participate in the maintenance GnRH neuronal function. Exposure to bisphenol A, an environmental contaminant that alters GnRH neuron activity, caused a shift in tet2 subcellular localization and a decrease in histone 3 lysine 4 trimethylation abundance at the GnRH promoter. Finally, evaluation of tet2 protein interactions in GT1–7 cells suggests that the influence of tet2 on neuronal function are not limited to nuclear mechanisms but could depend on mitochondrial function, and RNA metabolism. Together, these studies implicate tet2 in the maintenance of GnRH neuronal function and neuroendocrine control of male reproduction.
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