bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective Cultural Communication via Information and Communication Technologies and Social Media Use
Authors: Kavoura Androniki , Sylaiou Stella
Published: September 2018

Cultural organizations need to adopt contemporary methods and ways of communication for heritage management. Raising people's interest for cultural heritage may take place via the implementation of innovative communication tools that allow for engagement to take place. Research though has shown that cultural organizations are more reluctant than firms are to implement a two-way communication process with new technologies and social media. Do cultural organizations employ information and communication technologies (ICTs) and social media in an interactive approach? This chapter aims to illustrate the significance that should be attributed to innovation through the use of technology for communication purposes by cultural organizations. The way communication trends take place in the field of cultural management and communication is presented, along with an overview of the technological outlook that can be invaluable. The use of innovative communication tools that are employed by cultural organizations for their communication strategies has been little researched as a topic. This study aims to add to the literature on the use of social media, mobile devices, and ICTs by cultural organizations.
From the Psychoanalyst's Couch to Social Networks
Authors: Silvana de Rosa Annamaria , Fino Emanuele , Bocci Elena
Published: September 2018

Given the important role that psychoanalysis has played in the field of intervention on mental health for many years and the controversial debate that as therapeutical practice has been always originated and recently reactivated, it is of particular interest to discusses the actuality of the SRT 50 years later in the era of social networks. It does so by exploring the dynamics of the interchange between scientific and lay knowledge regarding psychoanalysis, psychiatry, and mental health in light of a corpus of spontaneous conversations among Facebook, Twitter, and Yahoo! Answers users from France and Italy compiled over a one-year period. The study enlarges psycho-social research on social networks, currently under the hegemony of sociometrics and computer science research. Briefly, in this new communicative scenario, the results of the study show how different target groups use new practices, showing their positioning: users act as “infomediaries” of expert knowledge, providing informal help and suggestions online; experts open the doors of their “physical rooms” to “cyber rooms.”
Mapping the Dissemination of the Theory of Social Representations via Academic Social Networks
Authors: Silvana de Rosa Annamaria , Dryjanska Laura , Bocci Elena
Published: September 2018

This chapter examines the role of academic social networks in the dissemination of the social representations literature. In particular, it takes into account 9414 entries filed in the specialized SoReCom “A.S. de Rosa” @-library. Each entry was assessed concerning the presence of the publication in the three academic social networks (Academia.edu, ResearchGate, and Mendeley), which amounted to 2956 total entries. The publications on social representations found in academic social networks have undergone some of the comparative analyses based on “big data” and “meta-data” filed in the SoReCom “A.S. de Rosa” @-library repositories, concerning authors' countries and institutional affiliations, years of publication by year, type of publication, etc. This allowed presenting the geo-mapping of the wider scientific production in social representations and comparative results with different types of publications. Overall, the academic social networks constitute excellent allies in spreading knowledge in spite of their still relatively modest use.
Online Dating/Dating Apps
Authors: Arias Vladimir Santiago , Punyanunt-Carter Narissra Maria
Published: September 2018

The use of communication technologies for romantic rendezvous is not new; for example, Dutton and Aron found that the use of computers for mediated-personal advertisement through visual and textual information for romantic assessment heightened the perception of attraction without significant differences between genders. In addition to the commencement of computer dating during the 1970s and 1980s, video-recording devices were also used to initiate trysts, but never became as popular as online dating is presently. Subsequently, a paramount question arises for CMC research: Why did computer dating and video dating not become as popular as online dating which is presently spreading worldwide? Future research should look at how closely online and offline courtship behaviors overlap each other, and research should also investigate the communication behaviors that individuals use on online apps compared to face-to-face interactions.
Online Social Networking Behavior and Its Influence Towards Students' Academic Performance
Authors: Masrom Maslin , Usat Selisa
Published: September 2018

Online social networking (OSN) is an online application that has grown rapidly in prevalence and popularity in recent years. This chapter synthesizes the literature review concerning use of OSN in school, college, and university, and academic performance of students. It offers definitions of OSN, followed by the status of current knowledge about the use of OSN and academic performance of students. Based on the secondary sources, it concludes the entry with recommendations for future research direction on the relationship between use of OSN and academic performance.
Social Media and Business Practices
Authors: Rathore Ashish Kumar , Ilavarasan P. Vigneswara
Published: September 2018

This chapter presents an overview of social media and its application in various business domains. Social media platforms are increasingly becoming important for business growth. This chapter introduces the social media platforms, their various definitions, and their reach. It describes different types and business models of the social media platforms. This chapter discusses how the social media platforms could be used in all the business domains with examples. This chapter will be useful to the students of general management, organization studies, strategic management, and social sciences.
Social Media Credit Scoring
Authors: Anderson Billie , Hardin J. Michael
Published: September 2018

This chapter provides an overview of credit scoring and discusses how credit scoring is evolving within the context of social media. The main focus of the chapter is how financial institutions have begun incorporating a credit applicant's social media activity such as Facebook and Twitter into the risk associated with a financial loan. Traditional financial organizations such as FICO to relatively new start-up companies such as Lenddo are highlighted; the way in which these companies are incorporating big data sources such as social media data into their loan-making decisions are discussed.
Social Network Analysis and the Study of University Industry Relations
Authors: Romero Fernando Cabrita
Published: September 2018

The aim of this chapter is to give an overview of the use of social network analysis in the study of university industry relations. The structure of networks can be analyzed through the lens of social network analysis. This methodological approach is briefly described, and its fundamental concepts are presented. The chapter reviews the applications of this approach on the study of university industry relations. Different structures in the relations may result in different innovation outcomes, and the use of SNA may be particularly useful to understand differential outcomes. This chapter is based on a review of available literature on the topics. The chapter aims at systematizing the information and knowledge related to the application of SNA on university industry networks, highlighting the main research pathways, the main conclusions, and pointing to possible future research questions.
Why It Is Difficult to Disengage From Facebook
Authors: Fakhfakh Sonda Bouattour
Published: September 2018

The huge popularity of social network sites like Facebook gave rise to numerous studies exploring the prerequisites and consequences of FB use. This chapter does not deviate from this direction. It offers a theoretic attempt to analyze the reasons of attachment to FB but through another perspective: the disengagement phenomenon. The theoretical framework is based on the attachment theory and the actor network theory. Assuming that FB allows the satisfaction of the innate attachment need and that there is a social and technical interaction between users and the FB structure, the present analysis investigates the relations between user attachment style and FB use and between FB user and the FB platform (hardware and software). The aim here is not to reject (or not) some formulated hypothesis, but to develop a theoretical frame from the existing theories. The argument is that human/human and human/non-human attachment could explain why users find it very difficult to disengage even though they are willing to do so and suffering from being invaded by FB.
Mining Sport Activities
Authors: Fister Jr. Iztok , Fister Iztok
Published: September 2018

For many people, sport is one of the stress-relieving activities. People being involved with sport wish to achieve attractive shape, healthy lifestyle, lose weight, and so on. However, there are also people who deal with sport because of competition goals. In order to fulfill their competition goals, they need to train properly. Even for professionals, it is very hard to perform a serious training. On the other hand, recent expansion of smart sport watches and even smart phones allow athletes to train smarter. During the months and years, they produce dozens of activity files. These files offer thousands of opportunities for data mining approaches, where athletes gained a deep insight into their training data. Data mining approaches are able to extract habits of athletes, help to prevent over-training syndrome and injuries, clustering similar activities together, and much more. In this chapter, the authors show opportunities for data mining, enumerate recent applications, and outline future potential for research and applications in the real world.
Literatura e suicídio: alguns operadores de leitura
Authors: André Willian
Published: September 2018

O objetivo deste artigo é oferecer alguns possíveis operadores de leitura para o desenvolvimento de análises sobre a questão do suicídio na literatura. A proposta parte da constatação de que, apesar de o autoaniquilamento ser um tema recorrente em manifestações literárias das mais diversas épocas, parecemos não possuir uma tradição de estudos que o contemple com maior atenção. Diante desse problema, e tentando não incorrer em uma sistematização estanque, desenvolvemos aqui algumas reflexões sobre possibilidades de abordagem e direcionamentos teórico-críticos, com o intuito de contribuir para a elaboração de um campo consistente de análise do suicídio em estudos sobre literatura e outras manifestações artísticas.
Estratégias de subjetificação na ficção contemporânea de mulheres: exílio, migração, errância e outros deslocamentos
Authors: Zolin Lúcia Osana
Published: September 2018

O artigo pretende refletir sobre a ficção contemporânea de mulheres, frequentemente marcada por processos de deslocamentos de ordem diversa, como exílio, migração, errâncias, representados/as como estratégias de subjetificação dos sujeitos no contexto pós-moderno. A pulsão de errância, muitas vezes, é aí solicitada como parte do esforço para a (re)construção identitária de personagens (quase sempre femininas), consubstanciado no repúdio de heranças genealógicas e nacionais, as quais são substituídas por afiliações a comunidades afetivas e a territórios descentrados. Teóricos da condição exílica, sobretudo Nouss (2016), nos subsidiarão nessas reflexões.
H1N1 Pandemic
Authors: Blake Nancy , Stevenson Kathleen , England Dawn
Published: September 2018

In March 2009, a child in Mexico was infected with novel influenza A (H1N1), otherwise known as swine flu. Otherwise healthy children in that small town came down with it shortly after, as well as others from other countries who had visited Mexico or been visited by someone from Mexico, as was the case in the United States. The Centers for Disease Control and Prevention confirmed the first 2 cases in April 2009 and has been working together with local health departments to do syndromic surveillance. In June 2009, the World Health Organization raised the pandemic alert to level 6. Pandemic H1N1, as it is now called, has infected otherwise healthy people younger than 25 years. Most patients present with fever, sore throat, and cough. Transmission is via droplets; therefore, appropriate precautions should be taken. Antiviral care is usually recommended for those who are hospitalized, and the virus has been found to be susceptible to oseltamivir (Tamiflu) and zanamivir (Relenza). Hospitals should work with local health departments for confirmation of the flu and implement pandemic plans as necessary.
Measurement of Primary Stability of Mini Implants Using Resonance Frequency Analysis
Authors: Singh Ashish Kumar , Kannan Sridhar , Arora Nitin , Bajaj Yatin , Revankar Ameet V.
Published: September 2018

Introduction

In the last decade, anchorage control with mini-implants has gained enormous credibility in maintaining orthodontic anchorage. Resonance frequency analysis (RFA) has proven to be an adequate method to measure the stability of these mini-implants because of its non-invasiveness and contactless measurement method.

Materials and Method

Tomas and S.K surgical mini-implants were tested. For this purpose custom fabricated attachment was fabricated to attach the smart peg on orthodontic mini-implant head, and 45 mini-implants were inserted in fresh swine pelvic bone in the density matched sites to that of most common sites where mini-implants are placed in human mandible. Mini-implants of two different lengths with diameter constant were also placed to assess the effect of length on primary stability.

Results

The mean ISQ of Group 1 (Tomas 10 mm) was 55.53±3.39 while that of Group 2 (S.K Surgical 10mm) was 56.63±3.48 and that of Group 3(S.K Surgical 8 mm) was 55.90±3.48. Difference among the groups were not statistically significant when ANOVA test was used (P >0.05).

Conclusion

The resonance frequency analysis is applicable to comparatively assess the primary stability of orthodontic mini-implants. There was no difference in primary stability of Tomas and S.K Surgical mini-implant and primary stability was not affected by the length of the mini-implant.
Cortical Piezo-Puncture as a Minimally Invasive Method for Reducing MiniScrew Implant Insertion Torque: A Preliminary in vitro Study
Authors: Gomez Juan Pablo , Giraldo Lisbetd , Montoya Daniela , Urrea Miguel
Published: September 2018

Objective

The objective of this study was to determine the effect of cortical piezo-puncture (CPP) on maximum insertion torque (MIT), maximum removal torque (MRT), and maximum axial load (MAL) during the insertion of self-drilling miniscrew implants (MSI), in an experimental model with proximal epiphysis of bovine tibia.

Materials and Methods

A comparative study was conducted using two groups of 20 self-drilling MSI inserted in intact bone (control group) and in bone with previous CPP (experimental group). MIT, MRT, and MAL of the 20 mini implants of each group were measured. Using SPSS software, Student’s t-test was applied to compare MIT and MRT and the U-test Mann–Whitney test was applied to compare MAL in both groups as well as Pearson and Spearman correlation.

Results

In the experimental group, average values of 12.85 (±4,32) Newton x centimeters (Ncm), 13.7 (±4,54) Ncm, and 22,474 (±895,95) gF for MIT, MRT, and MAL were found, respectively. In the control group, average values found for MIT, MRT, and MAL were 20.2 (±4,7) Ncm, 22.3 (±5,17) Ncm, and 4688,7 (±320,18) gF, respectively. Statistically significant differences were observed in MIT, MRT, and MAL between control and experimental groups (P < 0,001).

Conclusions

CPP before insertion of orthodontic MSI in bovine tibia significantly reduces MIT, MRT, and MAL.
Trends in C-Reactive Protein, D-Dimer, and Fibrinogen during Therapy for HIV-Associated Multidrug-Resistant Tuberculosis
Authors: Cudahy Patrick G. T. , Warren Joshua L. , Cohen Ted , Wilson Douglas
Published: September 2018

HIV-positive adults on treatment for multi drug-resistant tuberculosis (MDR-TB) experience high mortality. Biomarkers of HIV/MDR-TB treatment response may enable earlier treatment modifications that improve outcomes. To determine whether changes in C-reactive protein (CRP), D-dimer, and fibrinogen were associated with treatment outcome among those with HIV/MDR-TB coinfection, we studied 20 HIV-positive participants for the first 16 weeks of MDR-TB therapy. Serum CRP, fibrinogen, and D-dimer were measured at baseline and serially while on treatment. At baseline, all biomarkers were elevated above normal levels, with median CRP 86.15 mg/L (interquartile range [IQR] 29.25–149.32), D-dimer 0.85 µg/mL (IQR 0.34–1.80), and fibrinogen 4.11 g/L (IQR 3.75–6.31). C-reactive protein decreased significantly within 10 days of treatment initiation and fibrinogen within 28 days; D-dimer did not change significantly. Five (25%) participants died after a median of 32 days. Older age (median age of 38y among survivors and 54y among deceased, P = 0.008) and higher baseline fibrinogen (3.86 g/L among survivors and 6.37 g/L among deceased, P = 0.02) were significantly associated with death. After adjusting for other measured variables, higher CRP concentrations at the beginning of each measurement interval were significantly associated with a higher risk of death during that interval. Trends in fibrinogen and CRP may be useful for evaluating early response to treatment among individuals with HIV/MDR-TB coinfection.
Socioeconomic Factors Associated with Fasciola hepatica Infection Among Children from 26 Communities of the Cusco Region of Peru
Authors: Cabada Miguel M. , Morales Maria Luisa , Webb Camille M. , Yang Logan , Bravenec Chelsey A. , Lopez Martha , Bascope Ruben , White A. Clinton , Gotuzzo Eduardo
Published: September 2018

Fasciola hepatica is the most widely distributed trematode-affecting humans. The Andes Mountains are highly endemic for fascioliasis. We report results of a cross-sectional study evaluating the epidemiology of Fasciola among children in 26 agricultural communities in the Cusco region of Peru. Children 3 to 16 years old were enrolled in preschools and schools. Blood from participants was tested for complete blood counts, transaminases, and Fasciola antibodies. Stool samples were tested for Fasciola and other parasites. A total of 2,515 children were included in the analysis and the mean age was 9.6 years (±3.6). Ten percent (253) of the children had at least one positive test for Fasciola, 6% had chronic infection, and 0.4% acute infection. The rest of the subjects had only antibodies against Fasciola. The prevalence of infection varied from 0% to 20% between communities. Children with evidence of Fasciola exposure were older, lived at higher altitudes, and had a lower socioeconomic status than children without infection. The logistic regression analysis showed that children from Ancahuasi district, older children, and children with higher measures of poverty were more likely to have Fasciola exposure. Fascioliasis is common in the Cusco region and associated with poverty. However, the distribution varies markedly between communities.
Correlates of Late Presentation to HIV care in a South Indian Cohort
Authors: Rao Satish , AV Satheesh , Unnikrishnan Bhaskaran , Madi Deepak , Shetty Avinash K.
Published: September 2018

Late presentation to healthcare by HIV infected patients’ is common in India despite access to free combination antiretroviral therapy (cART). We assessed risk factors for late presentation among patients with a recent HIV diagnosis in an academic university–based antiretroviral treatment center. This retrospective study included 474 recently diagnosed HIV-infected patients registered for cART between 2012 and 2013. Subjects with CD4+ T-lymphocyte (CD4) count ≤ 350 cells/μL or with an AIDS defining event were defined as late presenters (LP) and patients with CD4 count ≤ 200 cells/μL or with an AIDS defining event were defined as LP with advanced HIV disease (LPAD). Multivariable logistic regression analysis was used to investigate factors associated with late presentation. Of the 474 patients, 356 (75.1%) were LP. Of these, 299 (83.99%) were LPAD and 57 (16.01%) LP were AIDS-free. Median CD4 count among LP was 134 cells/μL (interquartile range 72.25–219). Mean age of LP was 42.50 ± 8.88 years; 256 (71.9%) were males. Increasing age (> 51 years; Adjusted odds ratio [aOR] 4.19; P = 0.014) and rural residence (aOR 3.19; P = < 0.001) were independently associated with late presentation. HIV-positive housewives (aOR 0.34; P = 0.027), HIV-positive individuals with negative partners (aOR 0.48; P = 0.006), and partners with unknown HIV status (aOR 0.43; P = 0.007) were less likely to present late compared with positive partners of people living with HIV/AIDS (PLWHA). Most patients were LP despite free access to cART. Rural population and older PLWHA should be targeted while implementing HIV care. There is a need to strengthen the HIV care cascade by linking PLWHA to cART immediately after diagnosis.
Seroprevalence and Symptomatic Attack Rate of Chikungunya Virus Infection, United States Virgin Islands, 2014–2015
Authors: Hennessey Morgan J. , Ellis Esther M. , Delorey Mark J. , Panella Amanda J. , Kosoy Olga I. , Kirking Hannah L. , Appiah Grace D. , Qin Jin , Basile Alison J. , Feldstein Leora R. , Biggerstaff Brad J. , Lanciotti Robert S. , Fischer Marc , Staples J. Erin
Published: September 2018

When introduced into a naïve population, chikungunya virus generally spreads rapidly, causing large outbreaks of fever and severe polyarthralgia. We randomly selected households in the U.S. Virgin Islands (USVI) to estimate seroprevalence and symptomatic attack rate for chikungunya virus infection at approximately 1 year following the introduction of the virus. Eligible household members were administered a questionnaire and tested for chikungunya virus antibodies. Estimated proportions were calibrated to age and gender of the population. We enrolled 509 participants. The weighted infection rate was 31% (95% confidence interval [CI]: 26–36%). Among those with evidence of chikungunya virus infection, 72% (95% CI: 65–80%) reported symptomatic illness and 31% (95% CI: 23–38%) reported joint pain at least once per week approximately 1 year following the introduction of the virus to USVI. Comparing rates from infected and noninfected study participants, 70% (95% CI: 62–79%) of fever and polyarthralgia and 23% (95% CI: 9–37%) of continuing joint pain in patients infected with chikungunya virus were due to their infection. Overall, an estimated 43% (95% CI: 33–52%) of the febrile illness and polyarthralgia in the USVI population during the outbreak was attributable to chikungunya virus and only 12% (95% CI: 7–17%) of longer term joint pains were attributed to chikungunya virus. Although the rates of infection, symptomatic disease, and longer term joint symptoms identified in USVI are similar to other outbreaks of the disease, a lower proportion of acute fever and joint pain was found to be attributable to chikungunya virus.
Case Report: Ivermectin and Albendazole Plasma Concentrations in a Patient with Disseminated Strongyloidiasis on Extracorporeal Membrane Oxygenation and Continuous Renal Replacement Therapy
Authors: Boodman Carl , Chhonker Yashpal S. , Murry Daryl J. , Mah Allison , Grant Jennifer , Steiner Theodore , Libman Michael , Nishi Cesilia , Charles Marthe
Published: September 2018

Disseminated strongyloidiasis is often fatal, despite treatment with oral albendazole and parenteral ivermectin (IVM). Here, we report elevated plasma IVM and albendazole sulfoxide concentrations in the context of extracorporeal membrane oxygenation and continuous renal replacement therapy in a patient with disseminated strongyloidiasis treated with subcutaneous IVM and nasogastric albenzadole. Despite elevated drug plasma concentrations, live filariform larvae were detected in endotracheal aspirates after 2 weeks of treatment.
Impact of Chronic Kidney Disease on Chikungunya Virus Infection Clinical Manifestations and Outcome: Highlights during an Outbreak in Northeastern Brazil
Authors: Silva Junior Geraldo Bezerra da , Pinto José Reginaldo , Mota Rosa Maria Salani , Pires Neto Roberto da Justa , Daher Elizabeth De Francesco
Published: September 2018

The northeastern region of Brazil has faced in the last 2 years the largest outbreak of chikungunya virus (CHIKV) infection in its history. There are still few studies on kidney involvement in CHIKV. The aim of this study is to describe the impact of chronic kidney disease (CKD) on CHIKV clinical manifestations and outcome. This is a cross-sectional study conducted in the State of Ceara, northeastern Brazil, including all registered cases of CHIKV infection in the period from January 2016 to December 2017. Clinical manifestations were collected from the notification reports from official data bank from the State Secretary of Health of Ceara: National System of Diseases Notification and Laboratory Manager. A total of 182,731 cases were notified. Patients’ mean age was 32.4 ± 14.6 years, and 62.2% were female. The most common clinical manifestations were fever (88.6%), headache (72.9%), intense arthralgia (69.5%), and myalgia (65.6%). Hospital admission was required for 3,080 cases (3.3%), and death occurred in 383 cases (0.2%). Chronic kidney disease was reported in 691 cases (0.3%). Patients with CKD had a higher frequency of almost all clinical manifestations, including fever, myalgia, exanthema, vomiting, nausea, back pain, conjunctivitis, arthritis, severe arthralgia, petechiae, and retro-orbital pain. They also had a significantly higher frequency of diabetes, hematological disorders, liver diseases, hypertension, peptic ulcer disease, and autoimmune diseases. Mortality was significantly higher among CKD patients than patients without CKD (3.0% versus 0.2%, P < 0.0001).
Comorbidities in rheumatic arthritis
Authors: Kłodziński Łukasz , Wisłowska Małgorzata
Published: September 2018

Objectives

Rheumatoid arthritis (RA) is one of the most common systemic inflammatory diseases, but its etiology is still not fully known. The aim of this preliminary study was to assess what particular comorbidities are involved in the progression of RA and determine the influence that the aforementioned diseases have on each other.

Material and methods

Forty patients with diagnosed RA according to EULAR/ACR criteria from 2010 were included in the study. The majority of the group was female (n = 35; 87.5%). Patients were tested using routine laboratory and imaging methods allowing diagnosis and assessment of disease activity. Dual energy X-ray absorptiometry was also evaluated for mineral density. The activity of the disease was assessed using the disease activity score DAS28 (ESR) and SDAI (Simplified Disease Activity Index).

Results

Among studied patients, based on the DAS28 index, 9 patients were in the remission phase (22.5%) and 12 (30%) had high disease activity. Increased values ​​of CRP were observed in the majority of patients (65%). The group analysis demonstrated the most common comorbidities in patients with RA, as follows: hypertension (n = 14; 35%) and osteoporosis or osteopenia (n = 13; 32.6%).

Conclusions

Patients with rheumatoid arthritis (RA) are more susceptible to developing hypertension and osteoporosis. We did not observe a significant association between other comorbidities and activity of RA. The next study will assess a larger number of patients.
Systemic lupus erythematosus of the urinary tract: focus on lupus cystitis
Authors: Liberski Sławomir , Marczak Daria , Mazur Ewelina , Miętkiewicz Kacper , Leis Kamil , Gałązka Przemysław
Published: September 2018

Systemic lupus erythematosus (SLE) frequently manifests as urinary tract disease, most commonly in the form of lupus nephritis. Bladder involvement in the disease course takes a subclinical form and may affect both children and adults. Lupus cystitis can precede SLE diagnosis and may present with very unspecific urinary and digestive tract symptoms or no symptoms at all. The exact mechanism of bladder inflammation in lupus is not fully understood; however, histopathological studies suggest a possible role of immune complex-mediated small vessel vasculitis. Lupus cystitis is a rare SLE manifestation, but poses a challenge for physicians, due to its complex diagnostics and treatment.
Estimating the saturation vapor pressures of isoprene oxidation
products C5H12O6 and C5H10O6 using COSMO-RS
Authors: Kurtén Theo , Hyttinen Noora , D'Ambro Emma L. , Thornton Joel , Prisle Nønne L.
Published: September 2018

Abstract. We have used COSMO-RS (the COnductor-like Screening MOdel for Real Solvents), as implemented in the COSMOTherm program, to compute the saturation vapor pressures at 298 K of two photo-oxidation products of isoprene: the dihydroxy dihydroperoxide C5H12O6, and the dihydroperoxy hydroxy aldehyde, C5H10O6. The predicted saturation vapor pressures were significantly higher (by up to a factor of 1000) than recent experimental results, very likely due to the overestimation of the effects of intramolecular hydrogen bonds, which tend to increase saturation vapor pressures by stabilizing molecules in the gas phase relative to the liquid. Modifying the hydrogen bond enthalpy parameter used by COSMOTherm can improve the agreement with experimental results – however the optimal parameter value is likely to be system-specific. Alternatively, vapor pressure predictions can be substantially improved (to within a factor of 10 of the experimental values for the two systems studied here) by selecting only conformers with a minimum number of intramolecular hydrogen bonds. The computed saturation vapor pressures were very sensitive to the details of the conformational sampling approach, with the default scheme implemented in the COSMOconf program proving insufficient for the task, for example by predicting significant differences between enantiomers, which should have identical physical properties. Even after exhaustive conformational sampling, COSMOTherm predicts significant differences in saturation vapor pressures between both structural isomers and diastereomers. For C5H12O6, predicted differences in psat between structural isomers are up to two orders of magnitude, and differences between stereoisomers up to a factor of 20 – though these differences are very likely exaggerated by the overestimation of the effect of intramolecular H-bonds. For C5H10O6, predicted differences between (stereo)isomers are below a factor of 3. In future studies of saturation vapor pressures of polyfunctional atmospheric oxidation products using COSMOTherm, we recommend first performing thorough conformational sampling, and subsequently selecting conformers with a minimal number of intramolecular H-bonds.
Effect of climate change on winter haze pollution in Beijing: uncertain and likely small
Authors: Shen Lu , Jacob Daniel J. , Mickley Loretta J. , Wang Yuxuan , Zhang Qiang
Published: September 2018

Abstract. Several recent studies have suggested that 21st-century climate change will significantly worsen the meteorological conditions leading to very high concentrations of fine particulate matter (PM2.5) in Beijing in winter (Beijing haze). We find that 81 % of the variance in observed monthly PM2.5 during 2010–2017 winters can be explained by a single meteorological mode, the first principal component (PC1) of the 850 hPa meridional wind velocity (V850) and relative humidity (RH). V850 and RH drive stagnation and chemical production of PM2.5, respectively, and thus have a clear causal link to Beijing haze. PC1 explains more of the variance in PM2.5 than either V850 or RH. Using additional meteorological variables does not explain more of the variance in PM2.5. Therefore PC1 can serve as a proxy for Beijing haze in the interpretation of long-term climate records and in future climate projections. Previous studies suggested that shrinking Arctic sea ice would worsen winter haze conditions in eastern China, but we show with the PC1 proxy that Beijing haze is correlated with a dipole structure in the Arctic sea ice rather than with the total amount of sea ice. Beijing haze is also correlated with dipole patterns in Pacific sea surface temperatures (SSTs). We find that these dipole patterns of Arctic sea ice and Pacific SSTs shift and change sign on interdecadal scales, so that they cannot be used reliably as future predictors for the haze. Future 21st-century trends of the PC1 haze proxy computed from the CMIP5 ensemble of climate models are overall very small and variable in sign. We thus find no evidence for a significant effect of climate change on Beijing haze.
Last Millennium Reanalysis with an expanded proxy database and seasonal proxy modeling
Authors: Tardif Robert , Hakim Gregory J. , Perkins Walter A. , Horlick Kaleb A. , Erb Michael P. , Emile-Geay Julien , Anderson David M. , Steig Eric J. , Noone David
Published: September 2018

Abstract. The Last Millennium Reanalysis utilizes an ensemble methodology to assimilate paleoclimate data for the production of annually resolved climate field reconstructions of the Common Era. Two key elements are the focus of this work: the set of assimilated proxy records, and the forward models that map climate variables to proxy measurements. Results based on an extensive proxy database and seasonal regression-based forward models are compared to the prototype reanalysis of Hakim et al. (2016), which was based on a smaller set of proxy records and simpler proxy models formulated as univariate linear regressions against annual temperature. Validation against various instrumental–era gridded analyses shows that the new reconstructions of surface air temperature, 500 hPa geopotential height and the Palmer Drought Severity Index are significantly improved, with skill scores increasing from 10 % to more than 200 %, depending on the variable and verification measure. Additional experiments designed to isolate the sources of improvement reveal the importance of additional proxy records, including coral records for improving tropical reconstructions; tree-ring-width chronologies, including moisture-sensitive trees, for thermodynamic and hydroclimate variables in mid-latitudes; and tree-ring density records for temperature reconstructions, particularly in high northern latitudes. Proxy forward models that account for seasonal responses, and the dual sensitivity to temperature and moisture characterizing tree-ring-width proxies, are also found to be particularly important. Other experiments highlight the beneficial role of covariance localization on reanalysis ensemble characteristics. This improved paleoclimate data assimilation system served as the basis for the production of the first publicly released NOAA Last Millennium Reanalysis.
Increased nitrogen enrichment and shifted patterns in the world’s grassland: 1860–2014
Authors: Xu Rongting , Tian Hanqin , Pan Shufen , Dangal Shree R. S. , Chen Jian , Chang Jinfeng , Lu Yonglong , Skiba Ute Maria , Zhang Bowen
Published: September 2018

Abstract. As the largest sector on the Earth’s land surface, the livestock system is not only a major contributor to global manure excreta that perturbs the global nutrient balance, but also a major emitter of greenhouse gases that warms the climate. Much attention has been paid to nitrogen (N) fertilizer and manure N applications to global croplands, however, there is still a lack of spatially-explicit estimates of continuous time-series datasets of manure and fertilizer N inputs in global grasslands. In this study, we therefore developed three global gridded datasets at a resolution of 0.5 degree × 0.5 degree for the period 1860–2014 (i.e., annual manure N deposition rate, synthetic N fertilizer use rate, and manure N application rate) by combining annual and 5-arc minute spatial data on pasture and rangeland with country-level manure and synthetic fertilizer N data from the Food and Agricultural Organization database (FAOSTAT). We found that total N inputs, sum of manure N deposition, manure and fertilizer N application to global grassland systems increased from 15.5 to 103.8 Tg N yr−1 during 1860–2014. Manure N deposition accounted for 83.7 % of the total N inputs, whereas manure and fertilizer N application accounted for 7.7 % and 8.6 %, respectively, during 2000–2014. At the regional scale, hotspots of manure N deposition remained the same during 1860–2014 (i.e., southern Asia, Africa, and South America), but hotspots of manure and fertilizer N application have shifted from Europe to southern Asia in the early 21st century. These three datasets could fill data gaps of N inputs in global and regional grasslands and serve as input drivers for ecosystem and biogeochemistry models to investigate the impacts of N enrichment on the global grassland system, greenhouse gas emissions, and environmental sustainability. Datasets available at https://doi.pangaea.de/10.1594/PANGAEA.892940.
Brief Communication: Evaluation and comparisons of permafrost
map over Qinghai-Tibet Plateau based on inventory of in-situ
evidence
Authors: Cao Bin , Zhang Tingjun , Wu Qinghai , Sheng Yu , Zhao Lin , Zou Defu
Published: September 2018

Abstract. Many maps have been produced to estimate permafrost distribution over the Qinghai-Tibet Plateau, however, the evaluation and comparisons of them are poorly understood due to limited evidence. Using a large number data from various sources, we present the inventory of permafrost presence/absence with 1475 sites/plots over the QTP. Based on the in-situ measurements, our evaluation results showed a wide range of map performance with the overall accuracy of about 59–82 %, and the estimated permafrost region (1.42–1.84 × 106 km2) and area (0.76–1.25 × 106 km2) are extremely large. The low agreement in areas near permafrost boundary and fragile landscapes require improved method considering more controlling factors at both medium-large and local scales.
Improving Youth Access to Mental Health Support through a Youth–Adult Partnership
Authors: Ross Laurie , Connors Lindsay Carpenter
Published: September 2018

Mental and behavioral health disorders are major issues facing young people in the United States; yet, the majority of youth who need support do not get help. Young people tend not to get help for 2 interacting reasons: system barriers that prevent youth from seeking help, and personal reasons that can influence them to forgo treatment. Youth–Adult Partnerships (Y-APs) have the potential to improve mental health programming and increase service utilization because they create space to blend youth and service provider knowledge and experience. This article provides a detailed case study of a youth–adult partnership’s 2-year community assessment and strategic planning process that led to the development of an innovative mental health model that has been sustained for 15 years. This article highlights the practices that contributed to adult transformation and the importance of adults’ roles as boundary spanners in the implementation and sustainability of an intervention that addresses both system barriers and personal reasons youth forgo mental health treatment.
Youth Workers’ Role in Engaging Youth in Health Advocacy for Community-Level Change
Authors: Toomey Maureen , Smathers Carol , Iaccopucci Anne M. , Johnston Karen , Johannes Elaine
Published: September 2018

Youth development professionals and volunteers, here referred to collectively as “youth workers,” need to be prepared to engage young people as health advocates. Youth workers need an understanding of public health principles; policy, systems, environment change approaches; and effective youth–adult strategies to move from viewing youth as participants to engaged leaders in community health issues. Embracing youth as partners will create effective partnerships and yield substantial positive health impacts for the youth, adults, and their communities.
INFLUENCE OF DIANILINE CROSS-LINKING SYSTEMS ON THE STRUCTURE, CURING MECHANISM, AND PROPERTIES OF POLYACRYLICESTER ELASTOMER
Authors: Saha Tuhin , Bhowmick Anil K. , Oda Takeshi , Miyauchi Toshiaki , Fujii Nobuhiko
Published: September 2018

To develop high-performance polyacrylicester (ACM) elastomeric components with higher scorch safety and superior thermal and mechanical properties, we replaced aliphatic diamine curatives with aromatic dianiline curatives. The influence of dianiline curatives 4,4′-(4,4′-isopropylidenediphenyl-1,1′-diyldioxy)dianiline, 4,4′-(hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline, and 4,4′-(1,1′-biphenyl-4,4′-diyldioxy)dianiline on the network structures and thermal, dynamic mechanical, and mechanical properties of ACM vulcanizates was investigated. The kinetics of vulcanization was analyzed for different dianiline curatives, with the use of rheometer curves. To understand the electronic properties and study the relation between chemical structure and reactivity, density functional theory was used. The time–temperature superposition principal was used to evaluate the activation energy for degradation of cross-linked samples. Finally, the curing mechanism of ACM in the presence of dianiline curative was studied with X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. These spectroscopic analyses suggested that the reaction mechanism took place via two steps: the first step was formation of the amide linkage and the second step was formation of imide linkages.
HYBRID SILANE TECHNOLOGY IN SILICA-REINFORCED TREAD COMPOUND
Authors: Wang Danling , Ren Fujun , Zhu Chenxi , Feng Jie , Cheng Qiming , Chen Sheng , Shen Guoli , Wang Feifei
Published: September 2018

The use of a silane coupling agent in silica-reinforced tread can effectively improve silica dispersion in the rubber matrix and strengthen the interfacial interaction between the rubber and filler; this is beneficial to the enhancement of tire grip under wet conditions and reduces tire rolling resistance. The monofunctional silane n-octyltriethoxysilane (OTES) can react with the silanol group of the silica surface and hence improve silica dispersion. It can also suppress silica reaggregation during tire processing. Two hybrid silanes, OTES and 3-mercaptopropylethoxy-bis(tridecyl-pentaethoxy-siloxane) (Si747) or OTES and bis(triethoxysilylpropyl)tetrasulfide (TESPT), were filled in silica-reinforced tread compounds. The effect of the two hybrid silanes on the silica was investigated via Fourier transform infrared spectroscopy and thermogravimetric analysis. The processing ability of the silica-filled compounds and the performance of the vulcanizates were also investigated. Our experimental results show that OTES is able to further react with the silica following reaction between the TESPT and silica and that it should be added when the molar amount of TESPT or Si747 is constant, to prevent reduction of the cross-link density. Furthermore, the addition of OTES can extend the scorch time, especially in Si747 and OTES compounds. In addition, OTES can improve silica dispersion and only has a slightly negative effect on the physical properties of vulcanizates.
DISPERSION OF NANOCLAY IN 1,4-POLYBUTADIENE
Authors: Montella G. , Purdy A. P. , Qadri S. B. , Bhattarai N. , Stroud R. M. , Roland C. M.
Published: September 2018

Two approaches to obtaining better dispersion of organo-modified nanoclay in high-molecular weight polybutadiene were assessed: (1) chemical modification of the polymer to increase its affinity for the silicate layers and (2) increasing the stretching component of the flow field used to mix the materials. As expected, the degree of dispersion, that is, the extent of intercalation of the polymer into the clay galleries and amount of exfoliation of the clay layers, increased with closer matching of the respective solubility parameters of the components. The efficiency of mechanical mixing was greater for flow fields dominated by stretching (extensional flow); less mix energy had to be expended to achieve a given level of reinforcement. However, without sufficient affinity of the polymer for the clay, complete exfoliation could not be obtained solely by mixing. Nevertheless, incomplete dispersion of the nanoclay still yields more than 40-fold increases in viscosity with 5% clay.
EFFECT OF SILICA LOADING AND COUPLING AGENT ON WEAR AND FATIGUE PROPERTIES OF A TREAD COMPOUND
Authors: Sridharan Harini , Guha Abhilash , Bhattacharyya Sanjay , Bhowmick Anil K. , Mukhopadhyay R.
Published: September 2018

The effects of highly dispersible silica and the nature of silane in a tire tread cap compound were studied with particular reference to dynamic mechanical properties, abrasion resistance, side force coefficient, and fatigue crack growth (FCG) properties. The rubber matrix chosen was a blend of solution grade styrene butadiene rubber and polybutadiene rubber. Six different loadings of silica were used. Bistriethoxysilylpropyltetrasulfide (S) was taken as the coupling agent. In addition, the potential of two new generation silanes, 3-octanoylthio-1-propyltriethoxysilane (N) and 3-mercaptopropyl-di [tridecan-1-oxy-13-penta ethyleneoxideethoxysilane] (V) was also explored at 70 phr silica loading. Optimum properties were obtained at 50 phr loading of silica (S50). The tensile moduli for the compounds increased sharply with silica loading. Higher values of tan δ, indicating higher hysteresis, were obtained in compounds containing higher filler dosage. However, enhanced abrasion resistance and side force coefficient were observed at higher loadings of silica due to an increased reinforcement phenomenon. The crack growth exponent (β) was lowest for S50. Among the silanes tested, V showed a 22% drop in tan δ at 70 °C, 11% drop in abrasion loss, and an increase in FCG rate. N exhibited a lower FCG rate as compared with the silane S.
Diversidad y distribución de la macrofauna edáfica en dos sistemas de manejo de Moringa oleifera (Lam.): relación con las propiedades del suelo
Authors: Noguera-Talavera Alvaro , Reyes-Sánchez Nadir , Mendieta-Araica Bryan
Published: September 2018

Con el objetivo de determinar la relación entre diversidad y distribución vertical de la macrofauna edáfica, y propiedades físico-químicas del suelo, se llevó a cabo un estudio en predios de la Universidad Nacional Agraria. Los ensayos tuvieron una duración de 9 meses, en los que se implementaron prácticas de manejo agroecológico, y manejo convencional en ocho unidades experimentales con dimensiones de 15 m x 30 m, seleccionadas de manera aleatoria. La metodología de muestreo fue la desarrollada por el Programa Internacional Biología y Fertilidad del Suelo Tropical. Fueron levantados 12 monolitos de 25 cm x 25 cm por práctica de manejo, a una profundidad de 30 centímetros. Se realizó identificación taxonómica a nivel de Phylum, clase, orden y familia; así como de grupos funcionales detritívoros, ingenieros del suelo, herbívoros y depredadores. Fue registrada mayor densidad de macrofauna en el sistema de conversión agroecológica (7424 ind/m2) en comparación al sistema de manejo convencional (1984 ind/m2), con alta concentración de individuos (7488 ind/m2) en los primeros 20 centímetros del perfil; y densidad proporcional del 56.2% en la profundidad 0 a 10 centímetros. Taxonómicamente se determinó dominancia de la clase Insecta en ambos sistemas de manejo. La distribución de familias de la macrofauna edáfi ca fue diferente entre sistemas, con evidente influencia del rol por profundidad de muestreo. El grupo funcional ingenieros del suelo predominó en conversión agroecológica; mientras los detritívoros lo hicieron en manejo convencional. Fue determinada la infl uencia de la calidad de micro hábitat en las propiedades físico-químicas del suelo con el componente biológico; demostrándose efecto de las prácticas de manejo sobre la densidad, diversidad y distribución de la macrofauna edáfica.