bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of using social network sites on academic performance: the case of Qatar
Authors: Al-Yafi Karim , El-Masri Mazen , Tsai Ray 
Published: April 2018

Purpose
Social network sites (SNSs) have been common applications attracting a large number of users in Qatar. Current literature remains inconclusive about the relationship between SNS usage and users’ academic performance. While one stream confirms that SNS usage may lead to addiction and seriously affect individuals’ academic performance, other studies refer to SNS as learning enablers. The purpose of this paper is twofold: first, it investigates the SNS usage profiles among the young generation in the Gulf Cooperation Council (GCC) represented by Qatar; second, it examines the relationship between the identified SNS usage profiles and their respective users’ academic performance.

Design/methodology/approach
The study follows a quantitative survey-based method that was adapted from Chen’s internet Addiction Scale to fit the context of social networks. Data were collected from students of two universities in Qatar, one private and another public. Respondents’ grade point average was also collected and compared across the different usage profiles to understand how SNS usage behavior affects academic performance.

Findings
Results reveal that there is no linear relationship between SNS usage and academic performance. Therefore, this study further investigates SNS usage profiles and identifies three groups: passive (low usage), engaged (normal usage) and addicted (high usage). It was found that engaged users demonstrate significantly higher academic performance than their passive and addicted peers. Moreover, there is no significant difference in the academic performance between passive and addicted users.

Research limitations/implications
This study is cross-sectional and based on self-reported data collected from university students in Qatar. Further research venues could employ a more general sample covering a longer period, differentiating between messaging tools (e.g. WhatsApp) and other pure SNS (e.g. Twitter), and to cover other aspects than just academic performance.

Originality/value
This study complements research efforts on the influence of technology on individuals and on the society in the GCC area. It concludes that engaged SNS users achieve better academic performance than the addicted or passive users. Contradicting the strong linear relationship between SNS and performance, as claimed by previous studies, is the main originality of this paper.
Leveraging intellectual capital in developing countries: evidence from Kenya
Authors: Ferramosca Silvia , Ghio Alessandro 
Published: April 2018

Purpose
The purpose of this paper is to explore how organization’s resources and community aspects shape intellectual capital (IC) performance in developing countries. In fact, it is still unclear to what level organizational aggregation can influence forms of IC performance in the simultaneous presence of strong traditional legacy and eagerness for development.

Design/methodology/approach
The study is based on a project of aggregation of artists in Kenya. It uses a mixed methods approach.

Findings
The analysis first documents that multiple capital resources, i.e., human, social, and organizational contribute to improve IC performance. Social and organizational resources have the largest positive effects. This study then supports the importance of community aspects in fostering IC performance. In this light, it appears to facilitate knowledge interaction and interrelationship networks rather than accentuate possible pre-existing groups’ rivalry.

Research limitations/implications
The results are inferred from a single case study, and so the reader is given the caveat that the results cannot be easily generalized. The evidence gathered can represent a useful ground on which to build future studies comparing different legal, social, cultural, and economic contexts.

Practical implications
This study gathers insights on how organization’s resources can lead to IC performance in developing countries and in a setting characterized by a high degree of institutional complexity. It also addresses the call for more research on programs implemented at local level to leverage IC and to valorize traditional knowledge in a sustainable and concrete way.

Originality/value
Evidence on IC in developing countries is still scant, besides their potential for growth. This study attempts to address this gap. Moreover, it pays attention to the context by analyzing the community aspects. Finally, the use of mixed methods further validates previous evidence on the relationship between organization’s resources and IC performance.
Platforms in Sub-Saharan Africa: startup models and the role of business incubation
Authors: David-West Olayinka , Umukoro Immanuel Ovemeso , Onuoha Raymond Okwudiri 
Published: April 2018

PurposeThe purpose of this paper is to examine the startup models adopted by entrepreneurs in launching platform enterprises, and the effectiveness of business incubators across Sub-Saharan Africa (SSA).Design/methodology/approachData reflecting origin, models, services, ownership and other variables were collected on over 600 platforms and 196 incubators, and were analyzed using descriptive and inferential statistics.FindingsMarket portfolio of the platform startups is dominated by independent models, as incubators and accelerators were found to be inadequate in platform establishment within the region in terms of the services rendered to incubatees. The results also indicate that private ownership still dominates the startup ecosystem with a scant presence of public participation and almost a complete absence of public-private partnerships.Research limitations/implicationsThis exploratory study is constrained by a limited access to information on the platform ecosystem within the SSA region, curbing the scope of empirical work; but serves as a foundation for further investigations within the domain.Practical implicationsThe paper highlights the imperative for African Governments to make conscious efforts in driving enabling policies that will help bridge the gaps identified in facilitating the development of the region’s emergent platform economy.Originality/valueThe paper empirically elucidates the limited availability of critical resources necessary in supporting the successful development and growth of platform startups; and helps explain why the platform ecosystem within the region, though very active in the last decade, has not been laden with landmark and scaled innovations.
Intellectual capital of South Africa: a comparison with Poland and Romania
Authors: Lin Carol Y.Y. 
Published: April 2018

Purpose
The purpose of this paper is to uncover the national intellectual capital (NIC) of South Africa by making comparisons with Poland and Romania.

Design/methodology/approach
Based on a database of an NIC measurement model spanning 2001-2015, this study plotted the development trend of the NIC and its component capitals – human, market, process and renewal capitals. Their correlations with GDP per capita (ppp) (GDP hereinafter) were also presented.

Findings
The NIC of South Africa is lower than that of both Poland and Romania. Except for the increase of its human capital together with its GDP, the other capitals have lower relevance. Poland experienced highly correlated growth for its NIC and GDP, shedding light for South Africa. The qualitative findings are also reported.

Research limitations/implications
The IMD database carries South African data only for the African continent. Therefore, this paper cannot cover other countries from the continent.

Practical implications
There are three implications from both the quantitative and qualitative analyses: initiate national transformation from the two core issues of education and health; invite and provide attractive incentives for South African returnees from abroad and members of local private sectors to take part in the national transformation efforts; and learn from the NIC development pattern of Poland and Romania by investing in market capital and process capital as soon as possible for faster results.

Social implications
The research findings of this paper unveil the root of the social problems in South Africa, including education, health, high unemployment and so on. Suggestions are provided for mid-term and long-term potential solutions.

Originality/value
This paper demonstrates the value of an NIC in the economically successful Poland whose growth and GDP growth occurred at a similar pace.
How to write a company value statement that will achieve strategic impact
Authors: Vantrappen Herman , de Jong Rien 
Published: April 2018

Purpose
This article aims to present a novel, powerful and proven alternative for the flawed way in which firms traditionally state “company values”.

Design/methodology/approach
An analysis was made of the value statements of the 100 largest Fortune Global 500 firms. A literature search on company values was conducted. The authors’ field experience with the use of company values was applied.

Findings
A majority of large global companies have stated company values. There is abundant pundits’ advice on how to define, embed and live by company values. Nevertheless, stated company values generally have no impact on performance; worse, they may blow up in managers’ faces, with accusations of hypocrisy. The novel approach overcomes these shortcomings. First, it removes unnegotiable qualities, consigning these to the company’s code of conduct. Second, it no longer states a value as a singular point of perfection but as a position of a cursor on a scale.

Research limitations/implications
This approach looks at a value as a capability, that is, a resource that requires investment and development, one that helps the company to be more effective than its competitors and that its competitors would find hard to imitate readily.

Practical implications
This approach looks at a value as a capability, that is, a resource that requires investment and development, one that helps the company to be more effective than its competitors and that its competitors would find hard to imitate readily.

Originality/value
The article is of value to practicing managers. The approach helps the firm to distinguish itself from competitors in a positive and hard-to-imitate way. It stimulates productive open conversations between the firm’s managers and employees. It leads to statements that both reveal and reinforce the firm’s desired culture.
Lessons in strategic agility from two Drucker Forum thought leaders
Authors: Denning Stephen 
Published: April 2018

Purpose
Provides lessons in strategic agility from the presentations of two Drucker Forum thought leaders at the annual conference in Vienna in November.

Design/methodology/approach
Summarizes the Drucker Forum conference presentations of Steve Blank, a Silicon Valley serial-entrepreneur, and Professor Carlota Pérez.

Findings
Blank warns that, “Companies and government organizations are discovering that innovation activities without a defined innovation pipeline are likely to result in innovation theater.” 10; 10;Pérez believes the world has an historic opportunity to turn our environmental problems into economic solutions.

Practical implications
Pérez warns “Business is trapped in the illusion that a minimal state is always best.”

Originality/value
Steve Denning highlights paradigm shifting lessons that Blank and Pérez have to offer managers.
Antimicrobial susceptibility testing by Australian veterinary diagnostic laboratories
Authors: Hardefeldt LY , Marenda M , Crabb H , Stevenson MA , Gilkerson JR , Billman‐Jacobe H , Browning GF 
Published: April 2018

BackgroundThe national strategy for tackling antimicrobial resistance highlights the need for antimicrobial stewardship in veterinary practice and for surveillance of antimicrobial susceptibility in veterinary pathogens. Diagnostic laboratories have an important role in facilitating both of these processes, but it is unclear whether data from veterinary diagnostic laboratories are similar enough to allow for compilation and if there is consistent promotion of appropriate antimicrobial use embedded in the approaches of different laboratories to susceptibility testing.MethodsA cross‐sectional study of antimicrobial susceptibility testing and reporting procedures by Australian veterinary diagnostic laboratories was conducted in 2017 using an online questionnaire. All 18 veterinary diagnostic laboratories in Australia completed the questionnaire.ResultsKirby‐Bauer disc diffusion was the method predominantly used for antimicrobial susceptibility testing and was used to evaluate 86% of all isolates, although two different protocols were used across the 18 laboratories (CLSI 15/18, CDS 3/18). Minimum inhibitory concentrations were never reported by 61% of laboratories. Common isolates were consistently reported on across all species, except for gram‐negative isolates in pigs, for which there was some variation in the approach to reporting. There was considerable diversity in the panels of antimicrobials used for susceptibility testing on common isolates and no consistency was apparent between laboratories for any bacterial species.ConclusionWe recommend that nationally agreed and consistent antimicrobial panels for routine susceptibility testing should be developed and a uniform set of guidelines should be adopted by veterinary diagnostic laboratories in Australia.
The solution structure of monomeric CCL5 in complex with a doubly sulfated N‐terminal segment of CCR5
Authors: Abayev Meital , Rodrigues João P. G. L. M. , Srivastava Gautam , Arshava Boris , Jaremko Łukasz , Jaremko Mariusz , Naider Fred , Levitt Michael , Anglister Jacob 
Published: April 2018

The inflammatory chemokine CCL5, which binds the chemokine receptor CCR5 in a two‐step mechanism so as to activate signaling pathways in hematopoetic cells, plays an important role in immune surveillance, inflammation, and development as well as in several immune system pathologies. The recently published crystal structure of CCR5 bound to a high‐affinity variant of CCL5 lacks the N‐terminal segment of the receptor that is post‐translationally sulfated and is known to be important for high‐affinity binding. Here, we report the NMR solution structure of monomeric CCL5 bound to a synthetic doubly sulfated peptide corresponding to the missing first 27 residues of CCR5. Our structures show that two sulfated tyrosine residues, sY10 and sY14, as well as the unsulfated Y15 form a network of strong interactions with a groove on a surface of CCL5 that is formed from evolutionarily conserved basic and hydrophobic amino acids. We then use our NMR structures, in combination with available crystal data, to create an atomic model of full‐length wild‐type CCR5:CCL5. Our findings reveal the structural determinants involved in the recognition of CCL5 by the CCR5 N terminus. These findings, together with existing structural data, provide a complete structural framework with which to understand the specificity of receptor:chemokine interactions.DatabaseStructural data are available in the PDB under the accession number 6FGP
Necessary changes to improve animal models
Authors: Schaeffer L.R. 
Published: April 2018

SummaryAnimal models evolved from sire models and inherited some issues that affected sire models. Those issues include definition and treatment of contemporary groups, accounting for time trends and dealing with animals having unknown parents. The assumptions and limitations of the animal model need to be kept in mind. This review of the animal model will discuss the issues and will recommend enhancements to animal models for future applications.
Method for the estimation of genetic merit of animals with uncertain paternity under Bayesian inference
Authors: Shiotsuki L. , Cardoso F.F. , Albuquerque L.G. 
Published: April 2018

SummaryThe use of controlled mating or artificial insemination is impracticable in the case of large herds, mainly because of labour costs and the need to delimit areas during the breeding period. However, the exclusion of information from animals with uncertain paternity reduces genetic progress. The objectives of this study were as follows: (i) propose an iterative empirical Bayesian procedure to implement the hierarchical animal model (ITER); (ii) calculate the posterior probabilities of paternity by the maximum likelihood method following the concepts; (iii) compare an average numerator relationship matrix (ANRM), Bayesian hierarchical (HIER) models and ITER. Records of Nellore animals born between 1984 and 2006 from the zootechnical archive of Agropecuária Jacarezinho Ltda were used. For data consistency, records of contemporary groups (CGs) with fewer than three animals and animals whose records were 3.5 standard deviations above or below the mean of their CG were eliminated. After editing the data, 62,212 animals in the file and 12,876 animals in pedigree file were maintained, respectively. Spearman and Pearson correlations between the posterior mean of the genetic effects of animals were calculated to compare the ranking of animals for selection. Simulated data were used to confirm the veracity of the model. The correlations between ITER and HIER and between ITER and ANRM were similar evaluating different files, which decreased at the same proportion when only high‐ranked animals were evaluated. In conclusion, the model proposed herein is a suitable computational alternative to improve the prediction of breeding values of animals in genetic evaluations using large databases, including animals with uncertain paternity.
Changes in left atrial size and function early after cardiac resynchronization therapy as assessed by conventional two-dimensional echocardiography
Authors: Lupu Silvia , Mitre Adriana , Sus Ioana , Rudzik Roxana , Beke Ildiko , Dobreanu Dan 
Published: April 2018

Aims: Cardiac resynchronization therapy (CRT) was shown to improve left atrial (LA) size and function within months after the procedure. We aimed to assess the impact of CRT on left atrial (LA) size and function within days after the procedure. Materials and methods: Twenty-eight consecutive patients with CRT were evaluated before the procedure and within 3 days afterwards, and 25 of them were also examined at three months. Echocardiography was performed to assess LA size and function: LA volumes indexed to body surface (LAVIs) were measured at different moments during the cardiac cycle: ventricular end-systole – maximum LAVI (LAVImax), before atrial systole (LAVIpreA), and at ventricular end-diastole – minimum LAVI (LAVImin). These measurements were further used to calculate LA function parameters: LA total emptying fraction, activeemptying fraction and passive emptying fraction.Results: LAVImax decreased within days after the procedure – 45.5 mL/ m2 (38.2-56.7) vs. 42.9 mL/m2 (32.1- 56.2), p <0.05, as did LAVImin – 27.1 mL/m2 (22.9-41.9) vs. 25.9 mL/m2 (17.8-38.1), p <0.05, and LAVIpreA – 40.0 mL/m2 (31.3-53.0) vs. 35.5 mL/m2 (25.8-49.1), without significant changes in functional parameters. All LAVIs were correlated to the diastolic filling time/RR interval ratio after CRT, but not before.Conclusions: LAVIs may be reduced within days after the implant procedure in responders to CRT, while atrial functional parameters remain unchanged. Correlations beween LAVIs and the diastolic filling time/RR interval ratio after CRT suggest that early optimization of atrio-ventricular and ventriculo-ventricular delays may have a positive and immediate impact on LA size.
Effectiveness of Shear Wave Elastography in the diagnosis of acute pancreatitis on admission
Authors: Durmaz Mehmet Sedat , Arslan Serdar , Özbakır Bora , Güngör Gökhan , Tolu İsmet , Arslan Fatma Zeynep , Sivri Mesut , Koplay Mustafa 
Published: April 2018

Aim: We aimed to investigate the effectiveness of shear wave elastography (SWE) in the diagnosis of acute pancreatitis (AP).Material and methods: The pancreatic parenchyma of 50 patients whose clinical and laboratory findings were indicative of AP and of 70 healthy, asymptomatic volunteer participants with normal laboratory values was examined using SWE.Computed tomography was performed in all patients with AP on admission. Elastographic measurements were performed by manually drawing the contours of the pancreatic parenchyma using the free region of interest. The quantitative SWE values (meters/second [m/s], kilopascal [kPa]) of the patients and asymptomatic volunteers group were compared.Results: The mean SWE value of the pancreatic parenchyma was 2.60 ± 1.63 m/s in the asymptomatic volunteers and 3.48 ± 0.52 m/s in patients with AP, with a statistically significant difference (p<0.001, t=-3.685). The mean SWE value of the pancreatic parenchyma was 23.77±6.72 kPa in the asymptomatic volunteers and 45.71 ± 10.72 kPa in patients with AP, indicating a significant difference (p<0.001, t=-3.685). AP can be diagnosed with a sensitivity and specificity of 98.0% when 29.45 kPa was designated as cut-off value and with a 96.0% sensitivity and 98.3% specificity when 2.77 m/s was designated as the cut-off value. The superiority of SWE was found over B-mode US and CECT in the diagnosis of AP on admission. Conclusion: SWE can be used as an effective imaging method with high sensitivity and specificity for the diagnosis of AP. It may be used as an important imaging method to assist in the diagnosis of AP especially when B-mode US and CECT findings are normal.
Polymyxin B in Combination with Enrofloxacin Exerts Synergistic Killing against Extensively Drug-Resistant Pseudomonas aeruginosa
Authors: Lin Yu-Wei , Yu Heidi H. , Zhao Jinxin , Han Mei-Ling , Zhu Yan , Akter Jesmin , Wickremasinghe Hasini , Walpola Hasini , Wirth Veronika , Rao Gauri G. , Forrest Alan , Velkov Tony , Li Jian 
Published: April 2018

ABSTRACTPolymyxins are increasingly used as a last-resort class of antibiotics against extensively drug-resistant (XDR) Gram-negative bacteria. However, resistance to polymyxins can emerge with monotherapy. As nephrotoxicity is the major dose-limiting factor for polymyxin monotherapy, dose escalation to suppress the emergence of polymyxin resistance is not a viable option. Therefore, novel approaches are needed to preserve this last-line class of antibiotics. This study aimed to investigate the antimicrobial synergy of polymyxin B combined with enrofloxacin againstPseudomonas aeruginosa. Static time-kill studies were conducted over 24 h with polymyxin B (1 to 4 mg/liter) and enrofloxacin (1 to 4 mg/liter) alone or in combination. Additionally,in vitroone-compartment model (IVM) and hollow-fiber infection model (HFIM) experiments were performed againstP. aeruginosa12196. Polymyxin B and enrofloxacin in monotherapy were ineffective against all of theP. aeruginosaisolates examined, whereas polymyxin B-enrofloxacin in combination was synergistic againstP. aeruginosa, with ≥2 to 4 log10kill at 24 h in the static time-kill studies. In both IVM and HFIM, the combination was synergistic, and the bacterial counting values were below the limit of quantification on day 5 in the HFIM. A population analysis profile indicated that the combination inhibited the emergence of polymyxin resistance inP. aeruginosa12196. The mechanism-based modeling suggests that the synergistic killing is a result of the combination of mechanistic and subpopulation synergy. Overall, this is the first preclinical study to demonstrate that the polymyxin-enrofloxacin combination is of considerable utility for the treatment of XDRP. aeruginosainfections and warrants future clinical evaluations.