Design, modeling and synthesis of an in vitro transcription rate regulatory circuit

This paper describes the design, modeling and realization of a synthetic in vitro circuit that aims at regulating the rate of mRNA transcription. Two DNA templates are designed to interact through their transcripts, creating negative feedback loops that will equate their transcription rates at steady state. A mathematical model is developed for this circuit, consisting of a set of ODEs derived from the mass action laws and Michaelis-Menten kinetics involving all the present chemical species. The DNA strands were accordingly designed, following thermodynamics principles and minimizing unwanted interactions. Preliminary experimental results show that the circuit is performing the expected task, by matching at steady state the transcription rates of the two DNA templates

Scaling and Scale Breaking in Polyelectrolyte

We consider the thermodynamics of a uniformly charged polyelectrolyte with harmonic bonds. For such a system there is at high temperatures an approximate scaling of global properties like the end-to-end distance and the interaction energy with the chain-length divided by the temperature. This scaling is broken at low temperatures by the ultraviolet divergence of the Coulomb potential. By introducing a renormalization of the strength of the nearest- neighbour interaction the scaling is restored, making possible an efficient blocking method for emulating very large polyelectrolytes using small systems. The high temperature behaviour is well reproduced by the analytical high-$T$ expansions even for fairly low temperatures and system sizes. In addition, results from low-$T$ expansions, where the coefficients have been computed numerically, are presented. These results approximate well the corresponding Monte Carlo results at realistic temperatures. A corresponding analysis of screened chains is performed. The situation here is complicated by the appearance of an additional parameter, the screening length. A window is found in parameter space, where scaling holds for the end-to-end distance. This window corresponds to situations where the range of the potential interpolates between the bond length and the size of the chain. This scaling behaviour, which is verified by Monte Carlo results, is consistent with Flory scaling. Also for the screened chain a blocking approach can be devised, that performs well for low temperatures, whereas the low-$T$ expansion is inaccurate at realistic temperatures.Comment: 18 pages, latex, 6 figure

Sensitive Spectrophotometric Method for Quantitation of Guaifenesin and Dropropizine in Their Dosage Forms

Guaifenesin and dropropizine were analyzed through oxidation with periodic acid to give formaldehyde which was allowed to condense with 4-Amino-5-hydrazino-4H [1,2,4]-triazole-3-thiol (AHTT). The condensation product was further oxidized to yield a purple colored compound with maximum absorption at 550 nm. Beer's law was obeyed in the range of 5–45 μg mL−1 for guaifenesin and 10–80 μg mL−1 for dropropizine. Both drugs were also successfully determined in their dosage forms

Women’s Bodies, Battle Ground and Commodities: Violence against Women in Niger Delta, Nigeria

The Niger Delta, which is the mainstay of Nigeria economy, has a hidden epidemic of sexual violence against women. In other word, the Niger Delta crisis is gendered. Rape, sexual slavery and forced prostitution are all the vices perpetrated against women in the region. All these have physical, psychological and social consequences on the womenfolk and there is little or nothing the federal government of Nigeria is doing to stop these abuses and bring perpetrators to book. Violence against women remained pervasive, including domestic violence, rape and other forms of sexual violence by state officials and private individuals. The authorities in Nigeria have not been able to curb these excesses, leading to an entrenched culture of impunity. This paper therefore, examines the state insecurity for women and the role of the agencies providing humanitarian aid in the Niger Delta region.Keywords: Violence, Rape, Women, Insecurity, Humanitarian aid, Niger Delta Regio

Ansvar i det fjerne? : multinasjonale selskapers ansvar for ansatte hos leverandører og underleverandører i lavkostland : en kasusstudie av Ikea og Varner-gruppen

Utredningen tar for seg Ikea og Varner-gruppen, blant annet fordi begge har et høyt antall leverandører i lavkostland. Et sentralt tema er i hvilken grad kasusbedriftene tar ansvar for de ansatte hos leverandører og underleverandører i lavkostland. Her finner vi at bedriftene på mange områder tar innover seg det globale ansvaret de stilles overfor, men samtidig benytter begge strategier for å fraskrive seg og redusere sitt ansvar. Utredningen bruker blant annet et tradisjonelt interessentperspektiv og teori om samfunnsansvar som forretningskasus for å svare på hvordan og hvorfor selskapene velger å ta ansvar. Vi ser at bedriftene har mulighet til å utøve makt i verdikjeden, og at de burde være i stand til å påvirke arbeidernes rettigheter hos sine leverandører og underleverandører. I lys av DeGeorges retningslinjer for multinasjonale selskaper ser utredningen på kasusbedriftenes opptreden i lavkostland. Vi finner blant annet at tilstedeværelse, forbedringstilnærminger og kulturforståelse står sentralt for begge bedriftene

Biological indicators, genetic polymorphism and expression in Aspergillus flavus under copper mediated stress

AbstractFungi are considered model organisms for studying stress response and metal adaptation for both biotechnological and environmental purposes. In a previous study, copper was added in concentrations 1 and 10mM to Aspergillus flavus to induce laccase production for bioremediation, but using high concentrations of copper resulted in laccase inhibition despite the increase in bioremediation. In this study, the same copper sulfate was added and some oxidative biomarkers and antioxidative defense enzymes were assessed for stressed cultures of both copper and gamma radiation which was used as a positive stress inducer. The increase in copper concentrations resulted in an increase in superoxide dismutase enzyme activity, lipid peroxidation and protein carbonylation. On the other hand, catalase was inhibited by the addition of both copper concentrations, but exposure to gamma radiation resulted in an increased copper production. Glutathione peroxidase showed variation under stress, while both reduced glutathione and mycelial growth decreased in copper amended cultures. There was an increase in total endogenous carbohydrates. The main location of copper at the end of the incubation period seemed to reside in the cytosolic fraction of the fungus as detected by atomic absorption spectrometry. Genetic polymorphism was evident in the presence of copper as detected by RAPD-PCR. The expression of both laccase and superoxide dismutase suggest that each has a specific role in bioremediation, depending on the added copper concentration

Antibacterial Activity of Syrian Capparis spinosa. (Capparidaceae) Fruits and Roots

The ethanolic extract of Capparis Spinosa. Roots and Fruits were tested for their antibacterial activity against four species of bacteria, Bacillus subtilis, Escherichia coli, Klebsiella sp.and Staphylococcus aureus using disc diffusion technique. The extract concentrations of ethanolic roots and fruits extracts used were 0 (control), 125, 250, 500 and 1000 ppm in triplicates along with standard antibiotic, Ciprofloxacine (5 μg), Gentamycine (10 μg). Comparatively, ethanolic roots extracts showed higher activity than ethanolic fruits extracts. The results showed that In 1000 ppm ethanolic roots extract, a maximum of 3.2 cm ZI was observed against Staphylococcus aureus followed by 2.3 cm against Escherichia coli. The maximum ZI of 2.1 cm was recorded in 1000 ppm ethanolic extract of fruits against Pseudomonas aeruginosa followed by 1.5 cm against Bacillus subtilis. DOI: 10.7176/JBAH/9-18-02 Publication date:September 30th 201

To Get or Not to Get the Kaust Library E-Resources Acquisition Experience

In the challenging times of budget cuts and reviews, libraries are faced with issues such as justifying acquisition, negotiating deals and reviewing current subscriptions (pertaining to electronic resources) among others. With the rapid growth of electronic resources, libraries have to continuously assess their acquisition models and policies to constantly ensure that they are balancing their budget and users’ needs as well. This paper highlights the role played by Technical and Digital Services (TADS) section of King Abdullah University of Science and Technology (KAUST) library (Saudi Arabia) in acquiring the electronic resources (electronic books, electronic journals, databases, image and reference) for the community. It will describe the processes during the early days when KAUST library was inaugurated; how electronic resources were acquired and what went through during those days. The paper will elaborate further how the acquisition model has evolved and the various important roles played by the library staff in ensuring that acquisitions/subscriptions are justified, within the budget and provides ROI for the library. King Abdullah University of Science and Technology is a graduate research university which opened in September 2009 with its first cohort of 800 graduate students (25% female) taught by 100 faculties. The focus of study and research in the university are: Mathematics and Computer Science, Physical Sciences and Life Sciences. The university library started with 10 staff. The library has a “state-of-the-art learning and information resource center supporting graduate education and advanced scientific research” (KAUST, 2010)

Liver transplantation: Expanding the donor and recipient pool

Liver transplantation is an exemplar model of complex surgery and the only curative option for patients with end-stage liver disease. Although historically associated with poor outcomes, liver cancer management has also been revolutionised with liver transplantation and in some instances, survival outcomes are comparable to surgical resection. As such, the key elements underpinning the major advances in surgical technique, immunological therapies and allocation policies combined with improved patient and graft survival outcomes have created a huge demand for organ donation. Despite improvements in donor and recipient selection, there is a persistent disparity between organ supply and demand. Candidate wait-list mortality and dropout rates remain problematic and this concern has resulted in increased efforts to expand the donor pool to meet the unmet needs of the population. This is even more challenging when coupled with an ever-growing recipient pool, candidate waiting lists and an ageing population. Over the past two decades, there has been a considerable focus on extended criteria organs, donations after cardiac death and alternative avenues for marginal liver use. With careful donor selection and recipient matching, these livers may help bridge the gap between supply and demand and placate the ever-expanding recipient pool. Here, we present a summary of recent developments by the transplant community addressing the issues of a growing donor and recipient pool