Towards zero solid waste: utilising tannery waste as a protein source for poultry feed

Zero waste is now a strongly emerging issue for sustainable industrial development where minimisation and utilisation of waste are a priority in the leather industry. In a tannery hides and skins converted in to leather through various processes. Approximately 20% (w/w) of the chrome containing tannery solid waste (TSW) is generated from one tonne of raw hides and skins. However, tannery solid waste may also be a resource if it is managed expertly as we move towards zero waste. This research illustrates the potential of tannery solid waste as a poultry feed additive. An oxidation method was used to achieve 95% of dechroming rate of chrome tanned waste followed with thermal and enzymatic treatment to produce gelatin solution and collagen concentrates. The thermal stability and fibre structure of samples were analysed by Differential Scanning Calorimeter (DSC) and Scanning Electron Microscope (SEM). Protein content and fourteen amino acid concentrations were determined using amino acid analysis. High Performance Liquid Chromatography (HPLC) was used to compare the amino acid composition with wheat and soya bean meal that is conventionally used in poultry feed. The nutrient requirements for poultry feed vary according to the purpose for which they have been developed. The high content of arginine, leucine, threonine, serine and methionine in the extract were of a sufficient level for poultry feed. Hexavalent chromium test was performed and showed that levels of the metal were low enough to be used in feed additives. In addition, the extracted product showed 75% digestibility (in vitro) and appears that treated TSW may be utilised in poultry feed, this demonstrates a clear example of waste utilisation. In Bangladesh plans are being formed to use the extract in poultry feed production

Book Reviews: \u3ci\u3ePublic Accountability of Foundations and Charitable Trusts\u3c/i\u3e, Eleanor K. Taylor. New York: Russell Sage Foundation, 1953

Eleanor K. Taylor, in her book Public Accountability of Foundations and Charitable Trusts sketches the regulatory machinery in some twelve states and England and Canada, with a glance at the federal machinery in the form of the Internal Revenue Code and the Service which administers it. In the preparation of her study, a questionnaire was sent to the attorneys general of 48 states and two territories inquiring into the legal machinery in their states for the performance of the attorney general\u27s ancient duty of representing the public interest in connection with charitable trusts. Responses came from 33 states (Nebraska did not respond). The responses indicate that public benefit from charitable trusts is not the result of state enforcement. Question 1 of the questionnaire, What provision is there in your state for keeping a list of charitable trusts as they are established by will or otherwise? evoked 32 answers of none and 1 answer from New Hampshire that there exists a Special Register of Charitable Trusts. Question 2, Is there any official list in your office or elsewhere of charitable trusts now operating in your state? evoked the same responses. To question 3, Is there any provision whereby the attorney general periodically inspects charitable trusts to see whether they are being properly carried out, there were also 32 no\u27s and 1 (New Hampshire) yes

Constructing computer virus phylogenies

There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses - a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is "invented" only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimum number of edges. In general this optimization problem is NP-complete; some associated approximation problems are also hard, but others are easy. When tree solutions exist, they can be constructed and randomly sampled in polynomial time

Biological Consequences of Tightly Bent DNA: The Other Life of a Macromolecular Celebrity

The mechanical properties of DNA play a critical role in many biological functions. For example, DNA packing in viruses involves confining the viral genome in a volume (the viral capsid) with dimensions that are comparable to the DNA persistence length. Similarly, eukaryotic DNA is packed in DNA-protein complexes (nucleosomes) in which DNA is tightly bent around protein spools. DNA is also tightly bent by many proteins that regulate transcription, resulting in a variation in gene expression that is amenable to quantitative analysis. In these cases, DNA loops are formed with lengths that are comparable to or smaller than the DNA persistence length. The aim of this review is to describe the physical forces associated with tightly bent DNA in all of these settings and to explore the biological consequences of such bending, as increasingly accessible by single-molecule techniques.Comment: 24 pages, 9 figure

A 3D <i>in vitro</i> model reveals differences in the astrocyte response elicited by potential stem cell therapies for CNS injury.

Aim: This study aimed to develop a 3D culture model to test the extent to which transplanted stem cells modulate astrocyte reactivity, where exacerbated glial cell activation could be detrimental to CNS repair success. Materials & methods: The reactivity of rat astrocytes to bone marrow mesenchymal stem cells, neural crest stem cells (NCSCs) and differentiated adipose-derived stem cells was assessed after 5 days. Schwann cells were used as a positive control. Results: NCSCs and differentiated Schwann cell-like adipose-derived stem cells did not increase astrocyte reactivity. Highly reactive responses to bone marrow mesenchymal stem cells and Schwann cells were equivalent. Conclusion: This approach can screen therapeutic cells prior to in vivo testing, allowing cells likely to trigger a substantial astrocyte response to be identified at an early stage. NCSCs and differentiated Schwann cell-like adipose-derived stem cells may be useful in treating CNS damage without increasing astrogliosis

Rethinking the Baseline in Diversity Research: Should We Be Explaining the Effects of Homogeneity?

It is often surprisingly difficult to make definitive scientific statements about the functional value of group diversity. We suggest that one clear pattern in the group diversity literature is the prevailing convention of interpreting outcomes as the effect of diversity alone. Although work in this arena typically compares diverse groups with homogeneous ones, we most often conceive of homogeneous groups as a baseline—a reference point from which we can understand how diversity has changed behavior or what type of response is “normal.” In this article, we offer a new perspective through a focus on two propositions. The first proposition is that homogeneity has independent effects of its own—effects that, in some cases, are robust in comparison with the effects of diversity. The second proposition is that even though subjective responses in homogeneous groups are often treated as a neutral indicator of how people would ideally respond in a group setting, evidence suggests that these responses are often less objective or accurate than responses in diverse groups. Overall, we believe that diversity research may unwittingly reveal important insights regarding the effects of homogeneity.National Science Foundation (U.S.) (NSF Grant 0921728

Love Canal Tragedy

The purpose of this environmental failure case study paper is to provide educational materials for environmental engineering courses dealing with design and operation of landfills for hazardous waste. In 1978, it was discovered that hazardous waste had contaminated homes and schools in the Love Canal area, a former chemical landfill which became a 15 acre neighborhood of the City of Niagara Falls, New York. On August 7, 1978, the United States President Jimmy Carter declared a federal emergency at the Love Canal. The Love Canal became the first man-made disaster to receive such a designation based on a variety of environmental and health related studies. Background, causes and effects of environmental failure, and remediation actions of the Love Canal superfund site are described in this paper. Lessons learned from this case study show the importance of identification of hazardous waste and the proper disposal of hazardous waste for the protection of the public health and the environment

Love Canal Tragedy

The purpose of this environmental failure case study paper is to provide educational materials for environmental engineering courses dealing with design and operation of landfills for hazardous waste. In 1978, it was discovered that hazardous waste had contaminated homes and schools in the Love Canal area, a former chemical landfill which became a 15 acre neighborhood of the City of Niagara Falls, New York. On August 7, 1978, the United States President Jimmy Carter declared a federal emergency at the Love Canal. The Love Canal became the first man-made disaster to receive such a designation based on a variety of environmental and health related studies. Background, causes and effects of environmental failure, and remediation actions of the Love Canal superfund site are described in this paper. Lessons learned from this case study show the importance of identification of hazardous waste and the proper disposal of hazardous waste for the protection of the public health and the environment