111 research outputs found
Evaluation of Effective Composite Biosorbents Based on Wood Sawdust and Natural Clay for Heavy Metals Removal from Water
No full textBentonitic clay and wood sawdust are natural materials widely available in nature at low cost with high heavy metals sorption properties that, in this work, were combined to achieve an effective composite biosorbent with high sorption properties and enhanced mechanical stability. Pine, aspen, and birch wood sawdust, as well as different bentonite clays and different sawdust modification methods (H3PO4 or HCl) were used for preparing new composite biosorbents. A mixture of wood sawdust and bentonite in a ratio of 2:1 was used. All materials were characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM) methods and tested for Cu and Ni ions removal from water. The adsorption process for all composite biosorbents was well described from a pseudo-second order kinetic model (R-2 > 0.9999) with a very high initial adsorption rate of Cu and Ni ions and a maximum uptake recorded within 2 h. The results have shown that the adsorption capacity depends mainly on the kind of wood and the acid treatment of the wood that enhances the adsorption capacity. At a concentration of 50 mg/L, the biosorbent prepared using birch wood sawdust showed the worst performance, removing barely 30% of Cu and Ni ions, while aspen wood sawdust improved the adsorption of Cu (88.6%) and Ni (52.4%) ions. Finally, composite biosorbent with pine wood sawdust showed the best adsorption be haviour with an efficiency removal of 98.2 and 96.3% of Cu and Ni ions, respectively, making it a good candidate as an inexpensive and effective biosorbent for the removal of heavy metals
Producing open source software : how to run a successful free software project
No full textThe book tackles this very complex topic by distilling it down into easily understandable parts. Starting with the basics of project management, it details specific tools used in free software projects, including version control, IRC, bug tracking, and Wikis. Author Karl Fogel, known for his work on CVS and Subversion, offers practical advice on how to set up and use a range of tools in combInation with open mailing lists and archives. He also provides several chapters on the essentials of recruiting and motivating developers, as well as how to gain much-needed publicity for your project
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Book Review: An English Girl in New Guinea: Kathleen Haddon’s Journal and Photographs from New Guinea, September 16–November 18, 1914, by Kathleen Haddon, edited by Virginia-Lee Webb and Jonathan Fogel (2023)
No full textBook review: Kathleen Haddon, author, and Virginia-Lee Webb and Jonathan Fogel, editors, An English Girl in New Guinea: Kathleen Haddon’s Journal and Photographs from New Guinea, September 16–November 18, 1914. San Francisco, California: J. M. Fogel Media, Inc. and Premier Arts Editions, 2023. ISBN 13: 9781733007856. 192 pages, color illustrations, maps, portraits. Hardcover $89
A Three-Decade “Kuhnian†History of the Antebellum Puzzle: Explaining the shrinking of the US population at the onset of modern economic growth
No full textIn 1979, when anthropometric history was still in its infancy, Robert Fogel and collaborators reported that the height of the US male white population began to decline quite unexpectedly around the birth cohorts of 1830. This was quite a conundrum on account of the fact that according to conventional economic theory nutritional status was not expected to diminish at the outset of modern economic growth, i.e., at a time when incomes were growing robustly. Although many hypotheses were offered, not until 1987 was the comprehensive solution to the puzzle offered that the height decline was due primarily to a decline in food consumption: agricultural productivity did not keep pace with rapid population growth and urbanization. However, it took a third of a century for a Kuhnian paradigm shift to occur until most of the participants in the debate accepted the model elucidated by Komlos in 1987.Anthropometric history; Heights; Thomas Kuhn; Paradigm shift; USA; Antebellum Puzzle; Living Standards
Hikikomori in Japanese youth: some possible pathways for alleviating this problem from the perspective of dynamic systems theory
No full textjournal articleIn this paper, we will discuss the problem of hikikomori, in which an individual remains at home, typically isolated in the bedroom, with limited contact to the outside world. Hikikomori has been discussed primarily from a psychological perspective in Japan. In this paper, we take dynamic systems perspective, incorporating historical and cultural points of view. We address the question: "Is this a psychological (clinical) phenomena or a cultural-societal one?" The first author, Alan Fogel, has been doing research in the area of social and emotional development for more than 30 years. He worked at the University of Nagoya in 1983-84 as a Fulbright senior research scholar, where he conducted research on motherinfant communication and early childhood development with Professors Masatoshi Kawai and Hideo Kojima. During this period, Professor Fogel made several trips to visit the Research Center at Hokkaido University for discussions with Professors Kazuo Miyake and Shing-Jen Chen. Professor Fogel has made regular visits to Japan since that time. His perspective is that of an American developmental psychologist and educator who has some knowledge of Japanese history and culture
A Three-Decade “Kuhnian” History of the Antebellum Puzzle: Explaining the shrinking of the US population at the onset of modern economic growth
No full textIn 1979, when anthropometric history was still in its infancy, Robert Fogel and collaborators reported that the height of the US male white population began to decline quite unexpectedly around the birth cohorts of 1830. This was quite a conundrum on account of the fact that according to conventional economic theory nutritional status was not expected to diminish at the outset of modern economic growth, i.e., at a time when incomes were growing robustly. Although many hypotheses were offered, not until 1987 was the comprehensive solution to the puzzle offered that the height decline was due primarily to a decline in food consumption: agricultural productivity did not keep pace with rapid population growth and urbanization. However, it took a third of a century for a Kuhnian paradigm shift to occur until most of the participants in the debate accepted the model elucidated by Komlos in 1987
Tuberculosis: A disease without boundaries
No full textSummaryTuberculosis (TB) is an airborne disease caused by Mycobacterium tuberculosis (MTB) that usually affects the lungs leading to severe coughing, fever, and chest pains. Although current research in the past four years has provided valuable insight into TB transmission, diagnosis, and treatment, much remains to be discovered to effectively decrease the incidence of and eventually eradicate TB. The disease still puts a strain on public health, being only second to HIV/AIDS in causing high mortality rates. This review will highlight the history of TB as well as provide an overview of the current literature on epidemiology, pathogenesis and the immune response, treatment, and control of TB. In this race to combat a disease that knows no boundaries, it is necessary to have a conceptual and clear understanding of TB overall with the hope of providing better treatment through novel and collaborative research and public health efforts
Entrepreneurship in transition countries: a review
No full textThe aim of this paper is to provide an overview of the key issues surrounding entrepreneurship development in transition countries focusing on six main themes. Though it can be argued that the transition countries started from more or less the same point when they embarked on their transitional path, in this paper, we indicate a number of the differences in initial conditions which further influenced SME development. By surveying the existing literature on SME development, this paper illustrates that as the transition process progresses, entrepreneurship development in transition countries is a story of increasing divergence. The transitional context provides unique opportunities for entrepreneurship activities to develop. However, at the same time this environment presents unique challenges for entrepreneurial development especially knowledge-based entrepreneurship as the free-market system matures within a context with low levels of SMEs and inherited negative views towards entrepreneurship
The main periods and types of “urbanization” in Ancient Rus in VIII —XII century
No full textФогель Александр Сергеевич, кандидат исторических наук, доцент, ФГБОУ ВО «Самарский государственный экономический университет» (г. Самара). E-mail: [email protected].
A. S. Fogel, [email protected]
Samara State University of Economics, Samara, Russian FederationСтатья посвящена исследованию проблемы процессов градообразования и формирования городских сетей в Древней Руси VIII—XII вв. Автор предпринимает попытку систематизации основных типов городских поселений в указанный период по следующим критериям: наличие или отсутствие укреплений, размеры поселений, их основные функции, связь с процессами государствообразования, наличие или отсутствие связных городских сетей, плановость или спонтанность появления, связь с сельскохозяйственной округой и другие. На основании указанных признаков выявлены, описаны и проанализированы пять основных типов городских
поселений — таковыми могут считаться племенные грады, открытые торгово-ремесленные поселения (протогорода), княжеские погосты, крепости более позднего времени, с погостами не связанные, древнерусские города XI—XII вв. Все указанные типы, являющие собой малые и большие системы (сети), сменяли друг друга на протяжении указанного периода и вступали в различные взаимодействия, формируя единую городскую сеть Древней Руси.This article deals with the problem of processes of city formation and the formation of urban networks in the Ancient Rus’ in VIII—XII centuries. The Author makes an attempt to systematize the main types of urban settlements within a specified period according to the following criteria: the
presence or absence of fortifications, the size of settlements, their main functions, the relationship with the processes of state formation, the presence or absence of coherent urban networks, planning or spontaneity of the appearance, relationship with the agricultural community and others. Based on the characteristics identified, five basic types of urban settlements are described and analyzed— as such can be considered tribal grads, open trade and craft settlements (protocities), prince pogosts, castles
of a later time, not associated with the pogosts, the ancient city of XI—XII centuries. All mentioned types, which are small and large systems (networks), succeeded each other throughout the specified period and engaged in various interactions, forming a unified urban network of Ancient Russia
Illegal Aliens: Economic Aspects and Public Policy Alternatives
No full textThis article discusses the economic impact of illegal aliens on the United States economy. The author starts by briefly addressing four different kinds of impacts on the United States from illegal immigration: Sociopolitical, Population, Labor standards, and Social welfare costs. The author then examines the impact of immigration on the market including general trends, the effect of immigration on the market in the current period, the fear of American workers being displaced from their jobs, and the impact on employment and wages. Next the author examines immigration policy both as an ethical problem and how to restrict illegal immigration. The author concludes that the only way to prevent illegal immigration is to take away the incentive, which is employment, by making it illegal to hire illegal aliens and require legal workers to carry some sort of work card
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