University of Portsmouth

About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.

The impact of rainstorms on floods in ephemeral channels in southeast Spain

Abstract: This paper presents and discusses data on rainfall, stage and estimated discharge for a large flood occurring in two catchments in southeast Spain in September 1997. Rainfall and stage were recorded using automatic logging equipment and discharge was estimated using measurements of channel cross-sections and water depth estimated from trash lines. Total precipitation in the Rambla de Torrealvilla was 50 mm in 2 days with maximum rainfall intensities of 80 mm h−1. Total rainfall in the Rambla de Nogalte was 195 mm in 3 days, with maximum intensities of 200 mm h−1. In the Torrealvilla, this rainfall produced three flood peaks with maximum stage approaching 2.5 m. In the Nogalte, there was only one flood peak, which was 0.5 m deep. Estimated discharge varied widely throughout both catchments with maxima of 120 m3 s−1 in the Torrealvilla and 60 m3 s−1 in the Nogalte. Maximum discharges occurred at times of high rainfall intensity, but intensity alone did not explain why some tributaries had very small discharges. Variations in discharge in the ephemeral channels were due to combinations of lithology, morphology and land use. The predominantly marl catchment of the Torrealvilla had a lower threshold rainfall intensity than the schists of the Nogalte. Within each catchment sub-basins characterised by steep, gorge like terrain and sub-basins where agriculture had been abandoned both resulted in higher flood discharge. The contributing areas for the September storms were up to two thirds of tributary catchment areas. Comparison of rainfall data records shows that the September flood was the fifth largest on record and had a recurrence interval of 7 years. The largest (1973) flood, which is known to have caused substantial damage and a number of deaths, was only a 30-year event. The floods on the Torrealvilla destroyed at least two check dams and evidence suggests that these had little effect on reducing the impact of the floods.

The SDSS-II Supernova survey: Parameterizing the type ia supernova rate as a function of host galaxy properties

Abstract: Using data from the Sloan Digital Sky Supernova Survey-II (SDSS-II SN Survey), we measure the rate of Type Ia supernovae (SNe Ia) as a function of galaxy properties at intermediate redshift. A sample of 342 SNe Ia with 0.05 0.15) SNe Ia in highly star-forming galaxies. We consider that the high levels of dust in these systems may be obscuring the reddest and faintest SNe Ia.

Neural network modeling for estimation of partition coefficient based on atom-type electrotopological state indices

Abstract: A method for predicting log P values for a diverse set of 1870 organic molecules has been developed based on atom-type electrotopological-state (E-state) indices and neural network modeling. An extended set of E-state indices, which included specific indices with a more detailed description of amino, carbonyl, and hydroxy groups, was used in the current study. For the training set of 1754 molecules the squared correlation coefficient and root-mean-squared error were r2 = 0.90 and RMSLOO = 0.46, respectively. Structural parameters which included molecular weight and 38 atom-type E-state indices were used as the inputs in 39-5-1 artificial neural networks. The results from multilinear regression analysis were r2 = 0.87 and RMSLOO = 0.55, respectively. For a test set of 35 nucleosides, 12 nucleoside bases, 19 drug compounds, and 50 general organic compounds (n = 116) not included in the training set, a predictive r2 = 0.94 and RMS = 0.41 were calculated by artificial neural networks. The results for the same...

Ethical challenges in online research: Public/private perceptions:

Abstract: With its wealth of readily and often publicly available information about web users lives, the Web has created new opportunities for conducting online research. Although digital data is easily accessible, ethical guidelines are inconsistent about how researchers should use them. Some academics claim that traditional ethical principles are sufficient and applicable to online research. However, the Web poses new challenges that compel researchers to reconsider concerns of consent, privacy and anonymity. Based on doctoral research into the investigation of online medicine purchasing, this paper presents a case study involving online forums and reviews the existing ethical guidance surrounding the Web. The suggestion is that new ethical guidelines, particularly in relation to informed consent and participant’s own perceptions of what is public or private, are needed due to the unique challenges of online research.