Optimization of methodology for the simultaneous speciation of inorganic As, Sb and Se in fluid samples by sector-field ICP-MS coupled to HPLC

Metal speciation provides information useful in the study of toxicity, bioavailability, adsorption, and redox behavior of element species. Based on inductively coupled plasma mass spectrometry (ICP-MS) coupled to high performance liquid chromatography (HPLC), in this project, a systematic investigation was made regarding chromatographic methods for the simultaneous speciation of arsenic (As), antimony (Sb) and selenium (Se) redox couples, and preservation strategies of these species. Finally, the developed method was applied to the analysis of hydrothermal water samples, with the purpose of studying As and Sb inorganic species distribution in hydrothermal systems. In the first study, a new method was developed for the simultaneous speciation analysis of inorganic As(III, V), Sb (III, V) and Se(IV, VI) in fluid samples by sector field-ICP-MS coupled with HPLC. Hamilton PRX-X100 anion-exchange column with EDTA (pH of 4.7) and 3% methanol as mobile phase was used for the separation of these species. The overall analysis time was within 11minutes for all six desired species. A thorough validation concerning stability of retention time, linearity and spike recovery was carried out. Low detection limits of these species, 0.02 à ¼g L-1 for As(III), 0.06 à ¼g L-1 for As(V), 0.2 à ¼g L-1 for Sb(III), 0.02 à ¼g L-1 for Sb(V), 0.2 à ¼g L-1 for Se(VI) and 0.4 à ¼g L-1 for Se(IV), make it possible for simultaneous study of competitive adsorption, redox behavior of these species. In the second study, preservation method and stability of As, Sb and Se redox couples were investigated in Fe- and Mn- rich water samples (groundwater, river water and lake water). As potential preservation strategies EDTA alone and EDTA combined with either HCl, HNO3, formic acid or acetic acid were studied and compared to unpreserved samples. The results showed that addition of EDTA combined with acidification to a pH of 3 successfully preserved all three redox couples for at least 11 weeks stored at 4 ï °C in the dark. EDTA alone (pH = 6) failed to preserve As and Sb species, especially for Sb(III) which was eventually completely oxidized in all samples. On the other hand, in the unpreserved samples, As, Sb and Se redox species showed different adsorption behaviors. As(III), Sb(III), Se(IV)) and As(V) were strongly adsorbed by Fe-(oxy)hydroxide and possibly Mn-(oxy)hydroxide. While Sb(V) and Se(VI) were not adsorbed in most cases. In the third study, the developed speciation method was used for the analysis of hydrothermal waters from Bali and Java, Indonesia. The results showed that the distribution of As and Sb species were closely correlated to Cl-, HCO3- and SO42-. Generally, in HCO3-type hydrothermal waters As(V) seemed the dominant species. In Cl-type samples, it is more complicated. Since extremely high concentration of Cl might be originated from either magma degassing (HCl gas) or seawater feeding, thus other oxidation processes may be involved in As species distribution. Our primary speciation results indicated that when the hydrothermal waters were affected by seawater feeding, As(V) was the main existing form, probably due to microbial activity. In SO4-type hydrothermal waters, As distribution is variable, either As(III) or As(V) could be the dominant species. In addition, an unknown As species was detected in 5 of the 18 samples, particularly in 2 samples this unknown species was even the main existing form for As, indicating that microbial activity was involved. For Sb species, Sb(V) was generally the main species in the analyzed samples

Human Development in Populorum Progressio: Challenging Uganda\u27s Development Claims

This study investigates and questions Uganda\u27s development claims and choice between confrontation and mutual respect among the people, using Paul VI\u27s notion of integral human development in Populorum Progressio and the requisite development principles, virtues and conditions or factors presented therein. In the study I have argued that the development claims of Uganda do not, to a significant degree, meet the standards of human development advocated by Paul VI in Populorum Progressio. The study shows that human dignity and its universality precipitate the significance of the question of integral human development, and consequently necessitate a relevant anthropology. The structure of the work is as follows: First, I espoused the influences behind Paul VI\u27s vision of human development. These influences shaped his notion of development and the principles he proposed for authentic human development. They facilitate the understanding of his doctrine in Populorum Progressio. Secondly, I highlighted the problems Paul VI was addressing, and thereafter his proposed solutions, and his understanding of the notion and nature of true development as being integral -- the development of the entire person and of all people. The principle underlying this vision of development is human dignity. On the basis of the universal character of this underlying principle, I have argued that integral human development ought to promote the human dignity of all people irrespective of age, sex, socio-economic and political status, tribe, nation, race and color. I highlighted and explained other principles and factors necessary for integral human development and related them to the most fundamental principle. Thirdly, I reconstructed an anthropology for integral human development which Paul VI proposed in Populorum Progressio. This aimed to build reaffirm the cohesive and fundamental principle. I argued and concluded that human dignity is de facto the most fundamental principle that ought to be understood, acknowledged, and underscored. All other principles for human development are important but they revolve around it. Finally, I applied the principles presented in Populorum Progressio to the mediating structures of pastoral or religious, socio-economic and political life and community development in Uganda. Based on an understanding and respect for human dignity and its relation to other development principles, virtues and conditions I concluded that the application of the principles of integral human development is a failure in modern Uganda, to a significant extent, because the recognition and respect for human dignity is minimal in almost every context or sector. Consequently, among other recommendations, I have proposed education about human dignity and moral principles that promote human dignity as necessary, and one of the most crucial challenges to Uganda in this opening decade of the Twenty-First century and later

Volunteers in Museums: Are Small Museums Utilizing Volunteer Management Policies?

Volunteers are an asset to any museum. Having written volunteer management policies and procedures for museums can greatly increase the effective use of volunteers within a museum. This paper attempts to answer this question: Do small museums, which are most likely to need volunteers due to lack of paid staff and overall funding, utilize written volunteer management policies and procedures, and are these policies and procedures effective? To answer this question, survey results of four Southern Illinois region museums are analyzed. Two of the museums did have volunteer management policies and procedures, but did not necessarily exhaust all possible topics of volunteer management. The other two museums did not have written volunteer management policies and procedures, and the volunteer coordinators were unclear of the tangible benefits that a written volunteer management plan can have for a museum, its staff, its patrons, and the community it serves

The Western and Yoruba Concept of Beauty: A Comparative Analysis

Beauty is an important phenomenon in human life that cannot be ignored. Even the sceptics and the agnostics are at breast with this term. Just as one hears of Greek philosophy, Indian philosophy, African philosophy we also hear of Aesthetics, that is the study of beauty. This could either be from Western, Eastern or African perspectives. This tends to suggest that like philosophy, Beauty is culture- relative or relative to culture. The subject of aesthetic appreciation in Western culture for example is preserved in museums, whereas in African culture, the objects of aesthetic appreciation take its roots in what Placide Tempel called vital forces, the ontological structure which permeates everything. This serves as the basis for communal values and practical reality of life. It is from this perspective that this paper attempts a comparison between the Western and African esthetical appreciation of beauty and argues the thesis that the African beauty is best appreciated by means of African standards and paradigms of aesthetics.LWATI: A Journal of Contemporary Research, 8(1), 286-296, 201

Joining Longer Queues: Information Externalities in Queue Choice

A classic example that illustrates how observed customer behavior impacts other customers\u27 decisions is the selection of a restaurant whose quality is uncertain. Customers often choose the busier restaurant, inferring that other customers in that restaurant know something that they do not. In an environment with random arrival and service times, customer behavior is reflected in the lengths of the queues that form at the individual servers. Therefore, queue lengths could signal two factors—potentially higher arrivals to the server or potentially slower service at the server. In this paper, we focus on both factors when customers\u27 waiting costs are negligible. This allows us to understand how information externalities due to congestion impact customers\u27 service choice behavior. In our model, based on private information about both the service-quality and queue-length information, customers decide which queue to join. When the service rates are the same and known, we confirm that it may be rational to ignore private information and purchase from the service provider with the longer queue when only one additional customer is present in the longer queue. We find that, due to the information externalities contained in queue lengths, there exist cycles during which one service firm is thriving whereas the other is not. Which service provider is thriving depends on luck; i.e., it is determined by the private signal of the customer arriving when both service providers are idle. These phenomena continue to hold when each service facility has multiple servers, or when a facility may go out of business when it cannot attract customers for a certain amount of time. Finally, we find that when the service rates are unknown but are negatively correlated with service values, our results are strengthened; long queues are now doubly informative. The market share of the high-quality firm is higher when there is service rate uncertainty, and it increases as the service rate decreases. When the service rates are positively correlated with unknown service values, long queues become less informative and customers might even join shorter queues

Content-Based Image Retrial Based on Hadoop

Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is able to retrieve images based on content on large-scale cluster and image sets effectively

Equilibrium in Queues Under Unknown Service Times and Service Value

In the operations research literature, the queue joining probability is monotonic decreasing in the queue length; the longer the queue, the fewer consumers join. Recent academic and empirical evidence indicates that queue-joining probabilities may not always be decreasing in the queue length. We provide a simple explanation for these nonmonotonic queue-joining strategies by relaxing the informational assumptions in Naor\u27s model. Instead of imposing that the expected service time and service value are common knowledge, we assume that they are unknown to consumers, but positively correlated. Under such informational assumptions, the posterior expected waiting cost and service value increase in the observed queue length. As a consequence, we show that queue-joining equilibria may emerge for which the joining probability increases locally in the queue length. We refer to these as “sputtering equilibria.” We discuss when and why such sputtering equilibria exist for discrete as well as continuously distributed priors on the expected service time (with positively correlated service value)