The inter-outburst behavior of cataclysmic variables

Existing International Ultraviolet Explorer (IUE) and American Association of Variable Star Observers (AAVSO) archive data was used to accomplish a large scale study of what happens to the ultraviolet flux of accretion disk systems during the quiescent intervals between outbursts and how it relates to the preceding outburst characteristics of amplitude and width. The data sample involved multiple IUE observations for 16 dwarf novae and 8 novae along with existing optical coverage. Results indicate that most systems show correlated ultraviolet (UV) flux behavior with interoutburst phase, with 60 percent of the dwarf novae and 50 percent of the novae having decreasing flux trends while 33 percent of the dwarf novae and 38 percent of the novae show rising UV flux during the quiescent interval. All of the dwarf novae with decreasing UV fluxes at 1475A have orbital periods longer than 4.4 hours, while all (except BV Cen) with flat or rising fluxes at 1475A have orbital periods less than two hours. There are not widespread correlations of the UV fluxes with the amplitude of the preceding outburst and no correlations with the width of the outburst. From a small sample (7) that have relatively large quiescent V magnitude changes between the IUE observations, most show a strong correlation between the UV and optical continuum. Interpretation of the results is complicated by not being able to determine how much the white dwarf contributes to the ultraviolet flux. However, it is now evident that noticeable changes are occurring in the hot zones in accreting systems long after the outburst, and not only for systems that are dominated by the white dwarf. Whether these differences are due to different outburst mechanisms or to changes on white dwarfs which provide varying contributions to the UV flux remains to be determined

Augmented growth of haematococcus pluvialis using nutrients from post hydrothermal liquefaction wastewater (PHWW)

This study was conducted to evaluate if a high-value algae species, Haematococcus Pluvialis, could be successfully cultivated utilizing nutrients derived from a concentrated wastewater source and produce the potent antioxidant astaxanthin at similar quantities to when it is grown on conventional media and nutrient sources. The primary wastewater used in this study was the aqueous product of hydrothermal liquefaction (HTL), which is an attractive process for the conversion of wet biomass to bio-crude oil. Using recycled nutrients from the post HTL wastewater (PHWW) or other wastewater sources for growing algae can reduce costs and synthetic nutrient inputs, which improves the sustainability of algae cultivation operations. In the first part of this work, we determined an appropriate dilution of PHWW to support algal growth and astaxanthin production, while avoiding significant inhibitory effects of PHWW that have been previously reported in the literature. PHWW, was characterized for nitrogen and phosphorus content and compared with other wastewater sources and conventional algal media. Then, H. Pluvialis cells acclimated on Bold’s Basal Media (BBM) were inoculated across a 0-2% PHWW gradient in a well plate to identify the algae’s tolerance for the PHWW. This result determined that H. Pluvialis cells were able to grow well at concentrations of PHWW up to 0.25% when mixed with BBM. In a second experiment designed to investigate algal preferences for different chemical forms of nutrients, H Pluvialis was inoculated in BBM having only nitrate or only ammoniacal nitrogen as the nitrogen source. The cell counts were measured daily with a hemocytometer, and nutrient removal was also measured. This experiment showed no significant differences in algal growth based on the chemical form of nitrogen provided. Using the concentrations of 0.125% and 0.25% PHWW that were determined in the first experiment to support good algal growth, another larger scale cultivation experiment was performed in three 1L flasks to confirm algal growth results in comparison to the BBM only control. In each of the respective media compositions, the total amount of inorganic nitrogen was held constant by removing only nitrate from the baseline BBM media recipe, replacing it with the corresponding concentration of total ammoniacal nitrogen (TAN) from PHWW. For the 0.125% and 0.25% PHWW treatments, the corresponding amount of nitrogen replaced was 5 and 10%, respectively. During this experiment, nutrient concentrations were measured daily, and the algae were able to reduce nitrogen concentrations from the various media mixes by at least 80%. Based on cell counts, the PHWW at 0.125% and 0.25% augmented the algae growth by 44% and 17%, respectively. The algae biomass from the BBM control media and the alternative media blends with PHWW nutrients was harvested and subjected to stress conditions of elevated light and salinity. Stressing the cells was intended to induce increased production of carotenogenic antioxidants, including astaxanthin, which was confirmed by a gradual reduction of the chlorophyll: carotenoid ratio. After encystment, astaxanthin production was quantified using high performance liquid chromatography (HPLC), and these data showed that it was reduced by 47.3% and 34.1% in the 0.125% and 0.25% PHWW augmented cultures, respectively. Even though the amount of astaxanthin was reduced for the PHWW treatments, the final harvest extracts of algae grown with PHWW presented a more diverse and complex carotenogenic profile. In conclusion, this study demonstrates that PHWW nutrients can enhance H. Pluvialis cell growth, but further work is needed to better understand and control the amount and types of carotenoids produced by H. Pluvialis. The long-term effects of acclimation and adaptation were not studied, and provide additional opportunities for improving overall system performance. In particular, acclimation could help mitigate inhibitory effects of the PHWW that were observed even when PHWW was added at very low levels. Finally, other sources of sustainable nutrients from wastewater with less inhibitory contaminants should be investigated to hopefully provide replacement of a larger fraction of the nutrients needed for large scale algae cultivation

Exposing Privacy Concerns in Mhealth

We conducted several exploratory focus groups to understand what privacy concerns Patients might have with the collection, storage and sharing of their personal health information, when using mHealth devices. We found that Patients want control over their health information, and we noticed privacy trends that were particular to Patients in the same age group and with similar health experiences

Faculty Recital:Sarah Gentry, Violin

Kemp Recital Hall Tuesday Evening August 26, 2003 8:00p.m

Chamber Music for Strings and Piano

Kemp Recital Hall Wednesday Evening October 6, 2004 8:00p.m

Reviews

Reviews of Collective bargaining in industrialised market economics, Appraising and exploring organisations London, Delivering the goods, a history of the Transport Workers' Union in New South Wales 1888-1986, Democracy and control in the workplace, Training contractors for results: a guide for trainers and training managers and Training entrepreneurs for small business creation, lessons from experienc

Anxiously attached: Personality predictors of privacy attitudes, trust, and willingness to share information on the internet

Privacy concerns surrounding Internet and technology use are higher now than ever, yet, people continue to use the Internet and Internet-connected technologies to share information without coercion and often with recipients they do not have a relationship with. Our research addresses how people’s personality, particularly two personality dimensions (anxiety and avoidance) together known as attachment style, affects their self-reported willingness to share and their actual sharing behavior. We conducted two studies on Amazon’s Mechanical Turk (N=984). Study 1 surveyed 500 participants (193 women, 304 men, 3 transgender) aged 20-79 (Mdn = 35, SD = 11.65); and Study 2 surveyed 484 participants (223 women, 260 men, 1 transgender) aged 19-78 (Mdn = 35; SD = 11.69). Multiple regression analyses controlling for demographics and the personality factors neuroticism and extraversion show that anxiously attached individuals are more concerned (ßs = .24 and .33) than less anxiously attached individuals about their private data being disclosed, yet paradoxically, they report more trust in the security of digital communications (ßs = .21 and .34), making them more likely to share personal information on the Internet (ßs = .26 and .22). This research bears theoretical implications (e.g., understanding the psychology of sharing behavior), as well as practical ones (e.g., for tailoring existing privacy and sharing controls to individuals based on their personality characteristics)

Application of Machine Learning in Melanoma Detection and the Identification of 'Ugly Duckling' and Suspicious Naevi: A Review

Skin lesions known as naevi exhibit diverse characteristics such as size, shape, and colouration. The concept of an "Ugly Duckling Naevus" comes into play when monitoring for melanoma, referring to a lesion with distinctive features that sets it apart from other lesions in the vicinity. As lesions within the same individual typically share similarities and follow a predictable pattern, an ugly duckling naevus stands out as unusual and may indicate the presence of a cancerous melanoma. Computer-aided diagnosis (CAD) has become a significant player in the research and development field, as it combines machine learning techniques with a variety of patient analysis methods. Its aim is to increase accuracy and simplify decision-making, all while responding to the shortage of specialized professionals. These automated systems are especially important in skin cancer diagnosis where specialist availability is limited. As a result, their use could lead to life-saving benefits and cost reductions within healthcare. Given the drastic change in survival when comparing early stage to late-stage melanoma, early detection is vital for effective treatment and patient outcomes. Machine learning (ML) and deep learning (DL) techniques have gained popularity in skin cancer classification, effectively addressing challenges, and providing results equivalent to that of specialists. This article extensively covers modern Machine Learning and Deep Learning algorithms for detecting melanoma and suspicious naevi. It begins with general information on skin cancer and different types of naevi, then introduces AI, ML, DL, and CAD. The article then discusses the successful applications of various ML techniques like convolutional neural networks (CNN) for melanoma detection compared to dermatologists' performance. Lastly, it examines ML methods for UD naevus detection and identifying suspicious naevi

Using a central Vehicle Holding Compound (VHC) in an open pipeline automotive order fulfilment system: a simulation study

Satisfying requests for specific vehicle variants in a timely manner may increase profit margins for the automotive producer and automotive dealers and may reduce the need to incentivise customers financially to make a purchase. Open pipeline order fulfilment systems have emerged in the automotive sector to allow dealers to fulfil a customer in a number of ways. Not only can a dealer search its own stock for a suitable match to a customer’s requested vehicle specification, the dealer can also search for a suitable vehicle in the planning, assembly or distribution pipeline. If a suitable match cannot be found, the dealer can submit a specific Build-to-Order request to the producer. This study examines the impact of adding a central vehicle holding compound (VHC) in such a system. Any dealer can search for a suitable vehicle match in the VHC. A simulation study of a real automotive fulfilment system is conducted to examine the effects on order fulfilment performance of establishing a VHC in a specific market. The simulation model incorporates important features that affect the management and control of the fulfilment system. The study shows that establishing a VHC in an open pipeline system has a significant effect on the level of use of each fulfilment mechanism and on fulfilment performance. A VHC results in significant reductions in lead time but can increase the total stock level in the system if the VHC operating conditions are not determined carefully. The insights and implications of the findings are discussed in detail. They are valuable in providing a base line to consider investment in a VHC and to decide the most appropriate operating policies