bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile Phones and Libraries/Information Centres
Authors: Idiegbeyan-Ose Jerome , Ifijeh Goodluck , Isiakpona Chidi D.
Published: June 2015

This chapter examines mobile phone use and behavior among users in library and information centres. It discusses both observed and perceived mobile phone behaviors among library users and advocates the control of identified negative trends in libraries. It recommends that user education should be intensified; law and legislations on mobile use in libraries should be enacted and guarded jealously. The chapter concludes that, though the use of mobile phones has revolutionized library and information services, it also redefined user behavior. Negative behaviors associated with the use of mobile phones among users will stop or at least reduce while libraries and librarians will continue to evolve ways and means to curb ugly trends.
Mobile Phone Behavior: An Emerged Discipline of Research
Authors: Yan Zheng , Chen Quan
Published: June 2015

Mobile phones are becoming the most ubiquitous technology in the history. Researchers in various disciplines of behavioral sciences have been extensively examining how people use mobile phones and what influences mobile phone use have on people's lives for nearly 25 years. This chapter attempts to provide an overall picture of the science of mobile phone behavior by describing the past, present, and future of this emerged discipline of study in behavioral sciences. It provides a detailed review of five major areas and six specific topics of mobile phone behavior research and a brief outline of three directions of future research.
Mobile Phone Sensing in Scientific Research
Authors: Liu Bo , Koc A. Bulent
Published: June 2015

Mobile phones have become the most popular electronic devices in people's lives during the past decade. In addition to the calling and sending text messages, mobile phones can perform operations similar to personal computers. With the advent of smartphones, it is possible for these devices to capture human behavior data, record location information, sense environmental changes, and even log and analyze sensor data for mobile sensing related scientific research. Researchers are discovering that mobile phone sensing is an exciting method that should not be underestimated. Mobile phone sensing can play an important role in data collection and processing in many research fields. This article reviews scientific research that uses the built-in sensors of smartphones or external sensors, discusses how and where mobile phones can be used for scientific research, and reports the collective experience the mobile phone sensing community has gained from the use of smartphone platforms.
Predicting Psychological Characteristics by Smartphone Usage Behaviors
Authors: Gao Yusong , Lei Minglong , Zhu Tingshao
Published: June 2015

In recent years, smartphones become rapidly popular across the world. Meanwhile, since mental health problems became more serious, psychological characteristics including personalities and mental health state draw more researchers' attention. Generally, self-report and interview are two mostly used techniques for assessing people's mental state or personality traits. In this chapter, we overviewed some researches that focused on accessing psychological characteristics by smartphone usage behaviors. Firstly, we discussed some previous researches analyzing smartphone usage behaviors and psychological characteristics, and further discussed typical research work predicting psychological characteristics based on smartphone usage behaviors. In these literatures, results indicated that most dimensions of users' mental state and personality traits could be identified from their smartphone usage fairly well.
The Psychological Challenges of Mobile Learning
Authors: Terras Melody M. , Ramsay Judith
Published: June 2015

Mobile learning is the use of wireless handheld devices to support learning and teaching across different psychological, social, physical and temporal contexts. Research focuses on the technology, user skills and preferences, contexts of use, guidelines for evaluation that support mobile learning. The 24/7 nature of mobile learning blurs traditional boundaries of time and space both physically and psychologically and presents a number of psychological challenges that are a product of the user's socio-cognitive profile: human mental processes are limited and rely upon environmental cues to support them. Learning occurs across times and contexts: mobile learners must plan, organise and keep track of learning material accessed at different times in different locations. This presents psychological challenges, as human mental resources are subject to well-established constraints. Understanding the psychological challenges and the skills necessary to overcome them are essential for the design of effective mobile learning experiences.
The Conceptualization and Assessment of Problematic Mobile Phone Use
Authors: Lopez-Fernandez Olatz , Kuss Daria J. , Griffiths Mark D. , Billieux Joël
Published: June 2015

Despite its many undoubted advantages, mobile phone use has been associated with harmful and/or maladaptive behaviour. Problematic mobile phone use is considered as an inability of individuals to regulate their use of the mobile phone, and it eventually leads to negative consequences in daily life. The first goal of this article is to define and conceptualize the various facets of dysfunctional mobile phone use. The second goal is to describe the various steps of validating an instrument to assess problematic mobile phone use. Such an instrument needs to (1.) specify the user's mobile phone behaviour (i.e., the applications they use on their mobile phone), (2.) provide accurate measures of actual mobile phone use, and (3.) assess the extent of problematic mobile phone use. A comprehensive review of the existing validated questionnaires is provided. The theoretical and methodological limitations of the existing measures are then discussed.
Mobile Phone Use Enhances Social Connectedness
Authors: Mentor Dominic
Published: June 2015

This article focuses on the relationship between everyday mobile messaging and social connectedness. It highlights studies in which people use mobile messaging as a means of cultivating and maintaining social connectedness. The article delves into the relevance of social connectedness through mobile messaging on a personal, group, and macro level. Included is a review of research studies and their methodologies on how mobile messaging, like texting, has been repurposed within organizations for a variety of service objectives, including mobile learning. The concept of social connectedness, as fostered by mobile phone messaging, is important in people's lives as it reflects their continuous and affective interactions and experiences with a single friend, family member, or a group. The cultivation of social connectedness can be used as an agent for socio-emotional goals that can feed healthy outlooks for various constituents of all ages. The potential constructive impact of social connectedness for people in mobile messaging communities vary from feelings of belonging and perceived usefulness to academic success.
Mobile Phones for Plastic Surgery and Burns: Current Practice
Authors: Giaquinto-Cilliers M. G. C. , Hartnick R. , Van der Merwe L. W. , Kotze J.
Published: June 2015

Mobile phones have progressively become an inseparable partner to plastic surgeons in their clinical practice. From using the mobile phone camera to take pictures of injuries and sending those for instant advice, to searching for the best evidence articles in peer review journals, mobile phones have changed the plastic surgeons' approach on the best way to manage their patients. The availability of information in mobile technology has allowed a growing market for education tools for plastic surgeons and patients and the use of social media for marketing purposes. With the increased availability of smartphone applications, these devices have the potential to be an invaluable tool for the modern in training and practicing plastic surgeon.
Positive Technology: Using Mobile Phones for Psychosocial Interventions
Authors: Konrath Sara
Published: June 2015

This article reviews the use of mobile phones in psychosocial interventions. Specifically, it reviews research studies that have used text messages (SMS) or smartphone applications (apps) to improve people's mental health, psychological well-being, or social relationships. Psychosocial interventions are emerging from the larger and more established mobile health (mHealth) literature of physical health interventions. The scientific knowledge of psychosocial interventions is currently quite limited, with only a few published large randomized control trials. Most of those are limited to North American or European participant samples. The advantages and disadvantages of mobile interventions are discussed, along with recommendations for best practices. The success of future research is dependent upon more researcher-friendly tools to implement interventions.
Connecting 'Round the Clock: Mobile Phones and Adolescents' Experiences of Intimacy
Authors: Weinstein Emily , Davis Katie
Published: June 2015

Mobile phone ownership is approaching ubiquity among contemporary adolescents and smartphone adoption continues to rise, affording unprecedented opportunities for social connection. Adolescents connect via text messaging and social media apps to sustain communication – often throughout their waking hours – with offline ties. Through both casual exchanges and intimate self-disclosure, adolescents reinforce and develop offline friendships and romantic relationships. Youth marginalized or socially isolated offline can also transcend geographic barriers and connect with new communities. However, digital technologies pose challenges to achieving intimate connections and online expression can complicate or even threaten offline relationships.
Sex, Cyberbullying, and the Mobile Phone
Authors: D'Antona Robin , Kevorkian Meline
Published: June 2015

Cyberbullying and sexting have made headlines and caused concern over their legality and potential risk to safety. In this article, the authors discuss cyberbullying and sexting behavior and examine the association with mobile phone use. Using research from leading researchers in the field, they provide information about the prevalence of cyberbullying and sexting, the mobile phone as an avenue for these behaviors, and solutions to prevent victimization. In conclusion, the authors recommend that awareness, guidelines, and monitoring are preventative rather than reactive. In order to develop this chapter, the authors used evidence from leading researchers in the fields of bullying and cyberbullying prevention. These researchers include Dorothy Espelage, PhD., Professor of Child Development in the Department of Educational Psychology at the University of Illinois at Urbana-Champaign and Dr. Tonja Nansel, senior investigator at the Eunice Kennedy Shriver Institute of Child Health and Development. In addition, they have included the most current information from scholarly articles written by researchers who diligently examine the emerging issues around sexting and cyberbullying. This includes the work of Bastiaensens, S., Vandebosch, H., Poels, K., Van Cleemput, K., DeSmet, A. and Bourdeaudhij, I.D.
Unleashing the Open Mobile Internet
Authors: Penchuk Robert A.
Published: June 2015

Proponents of network neutrality seek to regulate the Internet to ensure equal access by all members of society. Conversely, those who favor network diversity argue that continued Internet development in a free market society necessitates price and service discrimination, without stifling regulation. An alternative proposal is provided to this seemingly intractable problem – a proposal leveraging the shift towards mobile Internet access, and enabled by recently reallocated white-space, due to the transition to Digital Television (DTV), and by developments in multi-mode and cognitive radio technology. The Federal Communications Commission has the mandate to implement ad-hoc mobile Internet access in a way that will ensure fair and balanced Internet access driven by competitive market forces rather than regulation.
Mobile User Behaviors in China
Authors: Lei Minglong , Liu Weidong , Gao Yusong , Zhu Tingshao
Published: June 2015

The development of the mobile industry makes it necessary for scholars to study mobile user behaviors in the mainland of China. This article is divided into three main parts after a brief introduction of the current Chinese mobile phone market. The first part is to demonstrate mobile use and its influencing factors in the mainland of China, and then to determine the mostly studied mobile usages among those articles. The second part pays attention to the effect brought by the use of mobile phones, and then checks the relationship between mobile addiction and other social behaviors. The last part is to illustrate the methods employed in the mobile user behavior analysis. After stating the analysis process of user behaviors, the authors attempted to summarize the main features extracted from data mining technology. Finally, the authors put forward some possible directions under the topic of mobile user behavior after careful review of the related literature.
A Critical-Cultural Look at the Early Days of Camera Phone Use and MMS Picture Messaging
Authors: Lillie Jonathan
Published: June 2015

This article takes a critical, cultural look at the early era (roughly 2001 to 2007) of camera phone and MMS (multimedia messaging services) use by reviewing several user studies, mostly from European and Asian countries. The article complements this literature review by considering the role played by one of the main regional and global industry actors (Nokia) in shaping the technology and then responding to user trends and innovation. The studies reviewed show that early camera phone users embraced the technology as a significantly enhanced form of the portable analog camera, as opposed to being more enthralled with photo messaging as industry players like Nokia had hoped. The article concludes by arguing for continued use of the cultural studies approach to studying new media users, texts, and contexts (i.e., the multiple influences of industry and regional culture) at the same time.
Educational Potentials of SMS Technology
Authors: Yengin Ilker , Karahoca Adem
Published: June 2015

Using SMS text to receive and send information is not a recent technology. The idea of using SMS for teaching and learning purposes is also fairly old. Although there are some examples of using SMS technology in education, the educational potentials of SMS technology are still not well-documented in a wide perspective. SMS technology can be used in many different forms for educational purposes. In this article, the authors picture the possible educational use of SMS by providing a detailed analysis of the technology and examples of different research studies describing the successful SMS technology implementations in education. This article also provides a basis for compressive analysis of the technology, including possible benefits and drawbacks.
Cell Phone Conversation while Driving
Authors: Nurullah Abu Sadat
Published: June 2015

This article presents a review of studies on the conversational aspect of cell-phone use while operating a motor vehicle. Research has indicated that talking on a cell phone while driving poses a safety threat to people both in the vehicle and on the road. This is because cell phone conversations take considerable cognitive, visual, and physical demands on the person involved in this task. However, research has also shown that people engage in risky driving behavior, even after being cognizant of the dangers associated with it. Therefore, policies need to be implemented to thwart the use of cell phones while operating a motor vehicle, to educate people about the risks that this behavior poses, and in so doing, to make the road safer for drivers and pedestrians.
Cellular Phones Contribute to Dangerous Driving
Authors: Dula Chris S. , Martin Benjamin A.
Published: June 2015

In the U.S. alone, motor vehicle crashes (MVCs) are the leading cause of death for people aged 11 to 27, resulting in 32,367 deaths and 2,217,000 injuries in 2011 (NHTSA, 2013a). In 2012, distraction-related MVCs are believed to have killed over 3,000 and injured over 420,000 (NHTSA, 2013b). A highly prevalent distraction is cellular (cell) phone use by drivers. A variety of factors, including demographics, overconfidence in driving ability, psychological conditioning, and social norms contribute to the persistent pervasiveness of cell phone use while driving. Talking on cell phones is not the only problem as texting has become a common means of communication. Texting may be even more dangerous than talking as it often requires drivers to divert their eyes from traffic. This article reviews research on cell phone use by drivers and resultant safety hazards, while exploring possible solutions and future directions for research such as the use of Behavior-Based Safety approaches and changes in policies and laws.
Waste Time or Lose Life: Assessing the Risk of Phoning While Driving
Authors: Collet Christian
Published: June 2015

Several actions and/or operations might interfere with those required during car-driving and thus elicit dual task conditions. Those related to driving itself involve manipulating commands or instruments and should be automated during the learning to drive period to ensure safety. Others, independent of driving may be delayed (eating, smoking a cigarette). Finally, others like manipulating a navigation system or holding a cellphone have potential interference more or less related to driving. The authors now step back about 25 years to analyze the interference between driving and phoning and assess the risk associated with it. Epidemiology provides an overview of mobile phone use and hypotheses about accident causes. If hand-held phones obviously interfere with driving actions, the authors should explain why hands-free kits do not solve all safety concerns. Then, analyzing the operations affected by phoning and describing the objective measures revealing impaired driving performance will address this issue. The authors finally highlight the conditions for relatively safe phone use as well as those that should be banned. Deciding to phone or not will thus depend on driving safety education, during which skills of caution should have been learned.
Mobile Phone Technology for ALL: Towards Reducing the Digital Divide
Authors: Bryen Diane Nelson , Moolman Enid
Published: June 2015

The UN Convention on the Rights of Persons with Disabilities (CRPD) has been ratified by more than 137 countries. Among its 55 articles, access to information and communication technologies is highlighted. However, people with intellectual and communication disabilities continue to have limited access to mobile phone technologies. This article describes the potential of mobile phones for this population and what is known about its use by children and adults with intellectual disabilities as well as those with significant communication disabilities. Policy implications to reduce this digital divide will be proposed as well as needed research.
The Use of Mobile Phone Technology to Support People with Autism Spectrum Disorders (ASD)
Authors: Asaro-Saddler Kristie , Akhmedjanova Diana
Published: June 2015

The increasing accessibility and utilization of mobile phone technology has greatly enhanced the lives of many individuals, including those with disabilities such as autism spectrum disorders (ASD). In this article the authors provide a comprehensive review of the literature in the use of mobile phone technology to deliver interventions to support the communication skills, socialization skills, and academic skills of individuals with ASD. The majority of the studies reviewed in this emerging field indicate the potential effectiveness of mobile technology as a medium to deliver interventions; however, additional research in this field is warranted. Implications for practitioners and researchers, along with potential areas for future research, will be discussed.
Gender Equality Policies in Indian Hotel Industry
Authors: Gupta Megha
Published: June 2015

An awareness of the under-representation of women in top positions in the corporate world has prompted many corporations to review their policies and practices. If firms are to remain productive and competitive in an increasingly demanding global market place, they must recruit, retain, develop, and promote their most talented people, regardless of their sex. This is increasingly seen not only as the right or ethical thing to do, but also the smart thing to do. And in keeping with this realization, a small number of leading edge organizations are attempting to become more women-friendly. Having women in key positions is argued to be associated with long term company success and competitive advantage adding value through women's distinctive set of skills and creating cultures of inclusion through a diverse workforce. This chapter tries to evaluate the gender equality policies in selected Indian hotels and finds a mixed picture. The analysis suggests that majority of the hotels are not yet adopting pro- active policies to encourage the representation or empowerment of women in hotels. Female employees tend to be concentrated at entry or operational level and their presence is lower at senior positions. Based on the results study suggests the Indian Hotel industry to rework on HR policies to provide equal and equitable opportunities for female employees.
Does Consumers' Confidence Cause Consumption Spending?
Authors: Das Ramesh Chandra , Das Amaresh
Published: June 2015

The present chapter addresses the financial crisis issue in light of its effect upon the interplay between the consumers' confidence upon an economy and consumption spending of the households of the same economy. A simple correlation analysis for the quarterly data from January 1996 to October 2012 shows that the occurrence of the crisis has badly affected the consumers' confidence and consumption spending of the developed countries. Emerging countries have performed well despite the crisis. Also that majority of the developed countries with a few developing ones produce the result of bidirectional causalities whereas in leading emerging countries, consumption spending is making a change in confidence in a ‘causal' sense for the entire period of study. During pre-crisis phase the result show that the leading developed countries experience unidirectional causal relation from consumption to confidence. But in the post crisis phase seven out of twenty countries produce a line of causation going from consumption to confidence and nine countries fail to show any line of causation.
Market Fundamentals and Stock Pricing in Nigeria
Authors: Agu Chukwuma , Orji Anthony
Published: June 2015

This chapter investigates the relationship between stock pricing and behaviour of the stock market on one hand and micro and macroeconomic fundamentals in the Nigerian economy on the other from 1980-2009 using both primary and secondary data. Results from the primary survey indicate that the key drivers of share prices were neither broad macroeconomic indicators nor key indicators of the health of the firm. Prices were clearly shown to be much above levels that could have been determined by such indicators as posted profits of firms, amounts paid out as dividend and its regularity. Secondary data analysis equally show that the relationship between actual levels of the all share price index for the period of our analysis and during the financial crisis were not driven by “expected” variables. While its fundamental values are driven by monetary and relative price variables, actual values are driven by external sector variables and prices.
Corruption, Size of Government, and Economic Growth
Authors: Munir Qaiser
Published: June 2015

A big size government fosters corruption, which can lead to inefficiencies and resource costs that impede economic progress. In this chapter, it is argued that much of the previous studies have focused only on detecting the linear effects of corruption on growth. This study, therefore adopts the Threshold Autoregression (TAR) approach by using an annual panel data of 100 countries during 1990-2012 to evaluate any existence of a non-linear relationship. This study presents evidence that suggests the existence of a hump shaped (nonlinear) relationship between corruption and long-run economic growth. When the government size is small (11.518%), corruption positively affects economic growth. Whereas, when the government final consumption expenditure (% of GDP) is larger than 19.027%, corruption negatively affects economic growth. Furthermore, the result indicates that a non-linear relationship of the ‘Armey curve' exists in our panel of countries. Thus, a government should investigate whether government size is over-expanding or not when designing its public finance policy.
Waves of Financial Crisis
Authors: Chakrabarty Gagari
Published: June 2015

Historically, stock-market crashes and the resultant panic have ended in ultimate devastating impact on the real economy. Proper macroeconomic management and accomplishing macroeconomic objectives require, in terms of depth and width, sound health of financial system. Financial fragility is often taken as a prime factor in generating and aggravating crises. Moreover, with extensive economic integration, crises in one market immediately affect others through dynamic interlinkages or “contagion”. Hence, at this juncture, inquiry into market dynamics becomes crucial. This chapter intervenes here focusing on two past significant stock-market crises namely, the dot-com bubble and the melt-down of 2007-08. The chapter found significant volatility transmission channels primarily through past-volatility impacts. In recent era of fluctuation and instability, stock-markets are more integrated through strong and positive innovation and past-volatility impacts. The news-impacts, however, are less intense than past-volatility impacts. Moreover, even with increasing financial integration, there remains a basis for global portfolio diversification.
Impact of Microfinance on Poverty in the Context of Global Financial Crisis
Authors: Laha Arindam
Published: June 2015

The microfinance programme in the South Asia region has proven to be resilient to the shocks of global financial crisis. In fact, cross country experiences in South Asia reveal little impact of the global financial crisis on the penetration of the microfinance programmes to poor households. To explore the impact of microfinance on poverty in the backdrop of global financial crisis, an attempt has been made in this present study to examine the relationship between MFI's gross portfolio per active borrower and the measures of poverty. Empirical evidences based on Pooled Regression Analysis suggest that gross portfolio per active borrower is negatively and significantly associated with the poverty head count ratio or poverty gap measure, which is consistent with the author's hypothesis that micro loans reduce poverty. The poverty alleviation role of microfinance in South Asian countries is not changing its dynamics even in post-crisis scenario.
Nouvelle Cuisine: Platelets Served with Inflammation
Authors: Kapur Rick , Zufferey Anne , Boilard Eric , Semple John W.
Published: June 2015

Platelets are small cellular fragments with the primary physiological role of maintaining hemostasis. In addition to this well-described classical function, it is becoming increasingly clear that platelets have an intimate connection with infection and inflammation. This stems from several platelet characteristics, including their ability to bind infectious agents and secrete many immunomodulatory cytokines and chemokines, as well as their expression of receptors for various immune effector and regulatory functions, such as TLRs, which allow them to sense pathogen-associated molecular patterns. Furthermore, platelets contain RNA that can be nascently translated under different environmental stresses, and they are able to release membrane microparticles that can transport inflammatory cargo to inflammatory cells. Interestingly, acute infections can also result in platelet breakdown and thrombocytopenia. This report highlights these relatively new aspects of platelets and, thus, their nonhemostatic nature in an inflammatory setting.
Intestinal Fucose as a Mediator of Host–Microbe Symbiosis
Authors: Pickard Joseph M. , Chervonsky Alexander V.
Published: June 2015

Fucose is an l-configuration sugar found abundantly in the mammalian gut. It has long been known to be induced there by the presence of bacteria, but only recently have some of the molecular mechanisms behind this process been uncovered. New work suggests that fucose can have a protective role in both gut-centered and systemic infection and inflammation. This review highlights recent studies showing that, in addition to acting as a food source for beneficial gut symbionts, host fucose can suppress the virulence of pathogens and pathobionts. The relevance of gut fucosylation to human diseases also is discussed.
Determining professional nurses’ knowledge on the performance management and development system in Tshwane
Authors: Du-Plessis Moselene A.R.
Published: June 2015

Background: The implementation of the Performance Management and Development System (PMDS) is seen as being vital to the quality of care, resource management and inter-professional work. However, there is evidence that, at present, professional nurses lack the knowledge to implement such a system.Objectives: The aim of this study was to explore and describe professional nurses’ knowledgeregarding the implementation of the PMDS in selected primary healthcare clinics in Tshwane.Method: A quantitative, descriptive, exploratory design was used and convenience sampling was used to recruit respondents. A self-administered structured questionnaire was used to collect data from 39 professional nurses who were involved in managing the work performance of employees. The data were analysed quantitatively with Statistical Analysis System version 8.2 software.Results: The respondents had limited knowledge about the implementation of the performance management and development system.Conclusion: There is a need for educational initiatives before, during and after the implementation of the PMDS, such as quarterly PMDS workshops and routine catch-uptraining. These would address the lack of knowledge of respondents as seen from the results.
Daar doer in Duitswes
Authors: Van der Merwe Belia
Published: June 2015

No abstract available.
Ly, reis, skryf: Die Bosniese oorlog, Boeddhisme en die skryf van ’n roman
Authors: Morgan Naomi
Published: June 2015

No abstract available.
A knowledge sharing framework in the South African public sector
Authors: Mkhize Peter L.
Published: June 2015

In the knowledge economy, organisations are shifting their investment focus to intellectual capital in order to sustain a competitive advantage in the global marketplace. Organisational survival is increasingly dependent on the organisation’s ability to create and distribute knowledge that contributes to the improvement of performance. The purpose of this article is to evaluate individual knowledge-acquisition and sharing practices in the South African public sector. I applied the techniques of grounded theory analysis to extract themes from data that could provide insight into the knowledge sharing that takes place in the South African public sector. Findings revealed that the informal sharing of knowledge takes place in discussion forums within communities of practice through web-based, socially orientated platforms. These communities of practice are widespread throughout the public sector and are established with the purpose of soliciting expert knowledge from those who have been using open-source software successfully.
Меры Гиббса для обобщенной модели Поттса с радиусом взаимодействия два на дереве Кэли
Authors: Khatamov Nosirzhon Muidinovich , Madgoziev Ganizhon Turdibaevich
Published: June 2015

Изучается обобщенная модель Поттса на дереве Кэли порядка $k=3$. При некоторых условиях на параметры показано, что существует не более двух трансляционно-инвариантных мер Гиббса и континуум мер Гиббса, не являющихся трансляционно-инвариантными. Для любого нормального делителя $\widehat G$ индекса два группового представления дерева Кэли изучены $\widehat G$-периодические меры Гиббса. Доказано, что существует несчетное множество $\widehat G$-периодических (не трансляционно-инвариантных и не "шахматно"-периодических) мер Гиббса.
Метод стохастического предела и интерференция в квантовых многочастичных системах
Authors: Aref'eva Irina Yaroslavna , Volovich Igor Vasil'evich , Kozyrev Sergei Vladimirovich
Published: June 2015

Для многочастичных квантовых систем с дипольным взаимодействием с квантовым полем рассмотрена проблема транспорта энергии электронного возбуждения при помощи механизма экситонного переноса, основанного на квантовой интерференции. Показано, что при специальном выборе параметров взаимодействия в модели квантового графа можно достичь усиления переноса экситона на сток, пропорционального числу частиц в системе, а также подавить перенос на альтернативные стоки. Для описания динамики используется метод квантового стохастического предела. Отмечены возможные применения указанного механизма в процессах квантового фотосинтеза.
Influência da acidez e do teor de fósforo do solo no crescimento inicial do mogno
Authors: Cardoso Arnon Afonso de Souza , Santos José Zilton Lopes , Tucci Carlos Alberto Franco , Farias Elias Paiva , Moura Rodolfo Pessoa de Melo
Published: June 2015

A adubação fosfatada para espécies perenes nativas necessita de estudos, tanto em condições de campo, como na fase de mudas. No presente estudo, objetivou-se avaliar a interação entre calagem e níveis de fósforo no crescimento inicial e o acúmulo de nutrientes do mogno (Swietenia macrophylla King.), cultivado num Latossolo Amarelo Distrófico típico em casa de vegetação. O delineamento experimental utilizado foi o inteiramente casualizado em esquema fatorial, com três repetições. Os tratamentos foram constituídos de seis doses de P (11; 22; 44; 66; 88 e 110 mg dm-3), além do tratamento controle (sem a aplicação de P), combinadas com a aplicação de 500 mg dm-3 de calcário ou sem a adição do corretivo. A adição de doses crescentes de P com aplicação de calcário favoreceram o crescimento inicial e o acúmulo de nutrientes em mudas de mogno, todavia, sem apresentar interações entre si. A máxima eficiência econômica para a produção de matéria seca foi alcançada com a aplicação de 41,6 mg dm-3de P, associada com adição 500 mg dm-3 de calcário dolomítico.

 
The importance of interstitial particle scavenging by cloud droplets in shaping the remote aerosol size distribution and global aerosol-climate effects
Authors: Pierce J. R. , Croft B. , Kodros J. K. , D'Andrea S. D. , Martin R. V.
Published: June 2015

Abstract. In this paper, we investigate the coagulation of interstitial aerosol particles (particles too small to activate to cloud droplets) with cloud drops, a process often ignored in aerosol-climate models. We use the GEOS-Chem-TOMAS (Goddard Earth Observing System-Chemistry TwO-Moment Aerosol Sectional) global chemical transport model with aerosol microphysics to calculate the changes in the aerosol size distribution, cloud-albedo aerosol indirect effect, and direct aerosol effect due to the interstitial coagulation process. We find that inclusion of interstitial coagulation in clouds lowers total particle number concentrations by 15–21% globally, where the range is due to varying assumptions regarding activation diameter, cloud droplet size, and ice cloud physics. The interstitial coagulation process lowers the concentration of particles with dry diameters larger than 80 nm (a proxy for larger CCN) by 10–12%. These 80 nm particles are not directly removed by the interstitial coagulation but are reduced in concentration because fewer smaller particles grow to diameters larger than 80 nm. The global aerosol indirect effect of adding interstitial coagulation varies from +0.4 to +1.3 W m−2 where again the range depends on our cloud assumptions. Thus, the aerosol indirect effect of this process is significant, but the magnitude depends greatly on assumptions regarding activation diameter, cloud droplet size, and ice cloud physics. The aerosol direct effect of the interstitial coagulation process is minor (< 0.01 W m−2) due to the shift in the aerosol size distribution at sizes where scattering is most effective being small. We recommend that this interstitial scavenging process be considered in aerosol models when the size distribution and aerosol indirect effects are important.
Ozone and aerosol tropospheric concentrations variability analyzed using the ADRIMED measurements and the WRF and CHIMERE models
Authors: Menut L. , Mailler S. , Siour G. , Bessagnet B. , Turquety S. , Rea G. , Briant R. , Mallet M. , Sciare J. , Formenti P. , Meleux F.
Published: June 2015

Abstract. During the months of June and July 2013, over the Euro–Mediterranean area, the ADRIMED (Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region) project was dedicated to characterize the ozone and aerosol concentrations in the troposphere. It is first shown that this period was not highly polluted compared to previous summers in this region, with a moderate ozone production, no significant vegetation fire events and several precipitation periods scavenging the aerosol. The period is modeled with the WRF (Weather Research and Forecasting) and CHIMERE models, and their ability to quantify the observed pollution transport events is presented. The CHIMERE model simulating all kinds of sources (anthropogenic, biogenic, mineral dust, vegetation fires); the aerosol speciation, not available with the measurements, is presented: during the whole period, the aerosol was mainly constituted by mineral dust, sea salt and sulfates close to the surface and mainly by mineral dust in the troposphere. Compared to the AERONET (Aerosol Robotic Network) size distribution, it is shown that the model underestimates the coarse mode near mineral dust sources and overestimates the fine mode in the Mediterranean area, highlighting the need to improve the model representation of the aerosol size distribution both during emissions, long-range transport and deposition.
Arctic microbial and next-generation sequencing approach for bacteria in snow and frost flowers: selected identification, abundance and freezing nucleation
Authors: Mortazavi R. , Attiya S. , Ariya P. A.
Published: June 2015

Abstract. During the spring of 2009, as part of the Ocean–Atmosphere–Sea Ice–Snowpack (OASIS) campaign in Barrow, Alaska, USA, we examined the identity, population diversity, freezing nucleation ability of the microbial communities of five different snow types and frost flowers. In addition to the culturing and gene-sequence-based identification approach, we utilized a state-of-the-art genomic next-generation sequencing (NGS) technique to examine the diversity of bacterial communities in Arctic samples. Known phyla or candidate divisions were detected (11–18) with the majority of sequences (12.3–83.1%) belonging to one of the five major phyla: Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes, and Cyanobacteria. The number of genera detected ranged from, 101–245. The highest number of cultivable bacteria was observed in frost flowers (FFs) and accumulated snow (AS) with 325 ± 35 and 314 ± 142 CFU m L−1, respectively; and for cultivable fungi 5 ± 1 CFU m L−1 in windpack (WP) and blowing snow (BS). Morphology/elemental composition and ice-nucleating abilities of the identified taxa were obtained using high resolution electron microscopy with energy-dispersive X-ray spectroscopy and ice nucleation cold-plate, respectively. Freezing point temperatures for bacterial isolates ranged from −20.3 ± 1.5 to −15.7 ± 5.6 °C, and for melted snow samples from −9.5 ± 1.0 to −18.4 ± 0.1 °C. An isolate belonging to the genus Bacillus (96% similarity) had ice nucleation activity of −6.8 ± 0.2 °C. Comparison with Montreal urban snow, revealed that a seemingly diverse community of bacteria exists in the Arctic with some taxa possibly originating from distinct ecological environments. We discuss the potential impact of snow microorganisms in the freezing and melting process of the snowpack in the Arctic.
Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments
Authors: Bian Q. , May A. A. , Kreidenweis S. M. , Pierce J. R.
Published: June 2015

Abstract. Smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle and vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimates of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one third of the initial particle-phase organic mass (36%) was lost during the experiments, and roughly half of this particle organic mass loss was from direct particle wall loss (56% of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (44% of the loss). We perform a series of sensitivity tests to understand uncertainties in our simulations. Uncertainty in the initial wood-smoke volatility distribution contributes 23% uncertainty to the final particle organic mass remaining in the chamber (relative to base-assumptions simulation). We show that the total mass loss may depend on the effective saturation concentration of vapor with respect to the walls as these values currently vary widely in the literature. The details of smoke dilution during the filling of smog chambers may influence the mass loss to the walls, and a dilution of ~ 25:1 during the experiments increased particle organic mass loss by 64% compared to a simulation where we assume the particles and vapors are initially in equilibrium in the chamber. Finally, we discuss how our findings may influence interpretations of emission factors and SOA production in wood-smoke smog-chamber experiments.
Differences in microbial community composition between injection and production water samples of water flooding petroleum reservoirs
Authors: Gao P. K. , Li G. Q. , Tian H. M. , Wang Y. S. , Sun H. W. , Ma T.
Published: June 2015

Abstract. Microbial communities in injected water are expected to have significant influence on those of reservoir strata in long-term water flooding petroleum reservoirs. To investigate the similarities and differences in microbial communities in injected water and reservoir strata, high-throughput sequencing of microbial partial 16S rRNA of the water samples collected from the wellhead and downhole of injection wells, and from production wells in a homogeneous sandstone reservoir and a heterogeneous conglomerate reservoir were performed. The results indicate that a small number of microbial populations are shared between the water samples from the injection and production wells in the sandstone reservoir, whereas a large number of microbial populations are shared in the conglomerate reservoir. The bacterial and archaeal communities in the reservoir strata have high concentrations, which are similar to those in the injected water. However, microbial population abundance exhibited large differences between the water samples from the injection and production wells. The number of shared populations reflects the influence of microbial communities in injected water on those in reservoir strata to some extent, and show strong association with the unique variation of reservoir environments.
Estimates of micro-, nano-, and picoplankton contributions to particle export in the northeast Pacific
Authors: Mackinson B. L. , Moran S. B. , Lomas M. W. , Stewart G. M. , Kelly R. P.
Published: June 2015

Abstract. The contributions of micro-, nano-, and picoplankton to particle export were estimated from measurements of size-fractionated particulate 234Th, organic carbon, and phytoplankton indicator pigments obtained during five cruises between 2010 and 2012 along Line P in the subarctic northeast Pacific Ocean. Sinking fluxes of particulate organic carbon (POC) and indicator pigments were calculated from 234Th–238U disequilibria and, during two cruises, measured by a sediment trap at Ocean Station Papa. POC fluxes at 100 m ranged from 0.65 to 7.95 mmol m−2 d−1, similar in magnitude to previous results at Line P. Microplankton pigments dominate indicator pigment fluxes (averaging 69 ± 19% of total pigment flux), while nanoplankton pigments comprised the majority of pigment standing stocks (averaging 64 ± 23% of total pigment standing stocks). Indicator pigment loss rates (the ratio of pigment export flux to pigment standing stocks) point to preferential export of larger microplankton relative to smaller nano- and picoplankton. However, indicator pigments do not quantitatively trace particle export resulting from zooplankton grazing, which may be an important pathway for the export of small phytoplankton. These results have important implications for understanding the magnitude and mechanisms controlling the biological pump at Line P in particular, and more generally in oligotrophic gyres and high-nutrient, low-chlorophyll (HNLC) regions where small phytoplankton represent a major component of the autotrophic community.