bluuebunny/crossref_metadata_2025 huggingface dataset:
Barriers and challenges to international interactions of the faculty members in Iran
Authors: Nazarzadeh Zare Mohsen , Pourkarimi Javad , Rezaeian Sahba
Published: April 2018

Purpose

The purpose of this paper is to identify the barriers and challenges to international interactions of the faculty members in Iran.

Design/methodology/approach

To achieve the purpose, a qualitative phenomenological approach was used. The research population was all experts in the field of higher education in Iran, it included 17 experts who were selected through purposeful sampling by snowball method and based on theoretical saturation. To collect the data, a semi-structured interview was used and for the data analysis, an inductive content analysis was applied.

Findings

The findings showed that the barriers and challenges to faculty members’ international interactions can be defined through three main barriers: inside university barriers, outside university barriers, and individual barriers.

Practical implications

This research identified the barriers and challenges of faculty members’ international interactions in Iran. The method of this study can be applied in other applied fields as well.

Originality/value

This study adds to the authors’ knowledge about international interactions of the faculty members and also the barriers and challenges of these interactions, so to have more interactions of faculty members at the international level, universities should make an effort to identify barriers and eliminate them, more than ever.
University performance evaluation and strategic mapping using balanced scorecard (BSC)
Authors: Alani Farooq Salman , Khan M. Firdouse Rahman , Manuel Diana F.
Published: April 2018

Purpose

The purpose of this paper is to analyze and explore the effectiveness of using balanced scorecard (BSC) as a management tool in the evaluation of the performance and thereby the quality services of a University.

Design/methodology/approach

The survey was conducted among the various faculties and departments Sohar University through a well-defined questionnaire. The collected primary data were compiled, analyzed and a critical analysis was carried out using a null hypothesis, χ2, and regression analysis.

Findings

Our empirical result clearly reveals that there is a strong association exists between the strategic road map and the four perspectives of BSC.

Research limitations/implications

The study was carried out in Sohar University, Oman and the same can be extended to all the higher educational institutions globally.

Practical implications

The study reveals that the key performance measures identified under the classification the four perspectives of BSC, play a crucial role in establishing the framework based on the strategic map determined by the vision and the mission of the University.

Social implications

The study demonstrates that the BSC concept can be introduced to an educational institution to fill up the gap created between the creation of strategy and implementation of the same.

Originality/value

No study has investigated the performance evaluation of a higher education institution in Oman, using the four perspectives of BSC, and this is a first hand study.
Use of social media, student engagement, and academic performance of business students in Malaysia
Authors: Alshuaibi Mohammad Said Ibrahim , Alshuaibi Ahmad Said Ibrahim , Shamsudin Faridahwati Mohd. , Arshad Darwina Ahmad
Published: April 2018

Purpose

Social media is a popular communication tool for college students in many countries including Malaysia. Even though the literature indicates that the use of social media in a higher learning environment is likely to enhance academic performance of college students, the mechanism that explains such association is yet to be explored. Based on the claims that the integration of social media use is purposeful to enhance student engagement, the purpose of this paper is to investigate the role of student engagement as a potential mediator between social media use and academic performance of college students in Malaysia.

Design/methodology/approach

A total number of 227 business students in one of the public universities in Malaysia were randomly chosen to participate in this study. Questionnaire was used as the main data collection technique, which was personally administered during class sessions. Data were analyzed using structural equation modeling-partial least square (SEM-PLS).

Findings

The result showed the multidimensionality of student engagement. It also indicated that cognitive engagement mediated the relationship between social media and academic performance, but not behavioral, emotional, or agentic engagement. The result suggests that social media has the potential to be used in a learning environment as it promotes cognitive engagement of students in class and subsequently their academic performance and success.

Research limitations/implications

One of the limitations of the present study is that the generalizability of the finding to a much larger population of students may be limited as the sampled students were recruited from business students in one of the public universities in Malaysia only. Students of different academic programs in different universities may have a different pattern of using the social media.

Practical implications

This study will help higher learning institutions and educators think of ways to integrate the use of social media in learning activities to help students achieve better academic performance. As shown by the findings, such use can encourage students to be cognitively engagedt in class in which the students can be more active learners.

Originality/value

The present study adds to the literature in social media use by addressing the issue of how it helps enhance academic performance of college students in a single model. Past studies tended to examine the role of social media and student engagement and the effect of student engagement on academic performance separately. Furthermore, this study took into consideration various types of social media used by college students who tend to have multiple accounts.
The potential of computer-mediated internships for higher education
Authors: Bayerlein Leopold , Jeske Debora
Published: April 2018

Purpose

The purpose of this paper is to discuss the opportunities and limitations of computer-mediated internships (CMIs) for higher education providers (HEPs) and to outline how HEPs may maximize the benefits that arise from CMIs through strategic choices.

Design/methodology/approach

The paper provides a systematic assessment of the benefits, opportunities and limitations of CMIs. A particular focus of the paper concerns ways in which HEPs may utilize CMIs to maximize student learning as well as institutional benefits in terms of the use of expertise, collaborations and the achievement of institutional targets.

Findings

Benefits of CMIs include the more inclusive access of previously disadvantaged student groups to internship opportunities, as well as fewer restrictions for HEPs and employers. Given the right design, CMIs can provide a number of important learning opportunities to students while providing extensive opportunities for HEPs. However, the benefits of CMIs need to be viewed in line with the challenges that arise, such as the skill and expertise required to implement CMIs, the required investment of resources, and the currently limited acceptance of CMIs by employers.

Practical implications

The findings of the paper highlight that CMIs have the potential to be highly beneficial for HEPs and students. In addition, the paper showcases how HEPs may address the limitations of traditional internships, as well as the challenges that arise in relation to CMIs, through the systematic and well supported application of technological solutions.

Originality/value

The paper makes an important contribution to the literature because it is the first to evaluate the potential of CMIs for the providers of higher education programs.
Executive pensions, compensation leverage, and firm risk
Authors: White Reilly
Published: April 2018

Purpose

The purpose of this paper is to investigate how the structure of both CEO and non-CEO executive compensation affects the overall risk of a firm. The author focuses on the interplay between CEO and non-CEO executive compensation structure.

Design/methodology/approach

The author uses a hand-collected pension-database that employs both OLS and two-stage least squares regressions to determine the effects of inside debt on default risk using the distance-to-default framework. The database consists of 8,965 executive-year data points from 272 firms.

Findings

This paper accomplishes three major objectives: first, the author presents a significant extension of Sundaram and Yermack (2007) by including non-CEO executives; the author demonstrates how the differences in inside debt between CEO and non-CEO executives are directly related to firm risk; and that funding these pensions via a Rabbi Trust eliminates most of the risk-shifting effects. Firms with the lowest compensation leverage gap between CEO and non-CEO executives were most likely to observe the agency costs associated with high executive leverage. When compensation leverage structures were substantially different, or the pension was pre-funded, these effects are neutralized.

Originality/value

To the best of the author’s knowledge, the first paper addresses the effects of Rabbi Trusts on risk-shifting behavior between both CEOs and non-CEO executives. Further, the author extends Sundaram and Yermack (2007) using a hand-collected database six times larger than the original paper. By focusing on the “leverage gap” between CEOs and non-CEO executives, the author presents unique evidence that underlines the risk dynamics between CEOs and their boards.
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

Purpose

The 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/approach

Data 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.

Findings

Market 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/implications

This 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 implications

The 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/value

The 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

Background

The 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.

Methods

A 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.

Results

Kirby‐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.

Conclusion

We 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.

Database

Structural data are available in the PDB under the accession number 6FGP
Necessary changes to improve animal models
Authors: Schaeffer L.R.
Published: April 2018

Animal 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

The 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.
Plasma polymer film designs through the eyes of ToF-SIMS
Authors: Bernard Laetitia , Rupper Patrick , Faccio Greta , Hegemann Dirk , Scholder Olivier , Heuberger Manfred , Maniura-Weber Katharina , Vandenbossche Marianne
Published: April 2018

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is increasingly used for the detailed chemical characterization of complex organic materials. Of particular interest in biointerface materials, it provides the accurate molecular information on their surface, a prerequisite for the understanding of subsequent interaction with biomaterials. Plasma polymer films are promising biointerface materials, as tuning the deposition parameters allows the control over film stability and density of surface functional groups. However, the optimization of these film properties not only requires a detailed characterization of the film chemistry, but also that of the deposition mechanisms. Here, ToF-SIMS is used within its different operation modes to investigate those on several plasma polymer film designs. The detailed information on surface molecular chemistry, interface conformation, vertical and lateral chemical and cross-linking gradients is gathered and linked to the underlying deposition mechanisms. In combination with other techniques, the interpretation and understanding of the final functional property of the films in terms of protein adsorption and site-specific binding is achieved.
In its second year, March for Science grows up
Authors: Mervis Jeffrey
Published: April 2018

This year's event, set for 14 April, is only one element in a global pro-science movement.
NIH looks to punish reviewers who violate confidentiality
Authors: Brainard Jeffrey
Published: April 2018

Agency re-reviewed dozens of funding proposals after officials discovered a violation of the rules.
A one-man fossil rescue mission
Authors: Kumar Sanjay
Published: April 2018

An amateur fossil enthusiast spends countless hours—and his own money—saving fossils from looting.
SLAM-seq defines direct gene-regulatory functions of the BRD4-MYC axis
Authors: Muhar Matthias , Ebert Anja , Neumann Tobias , Umkehrer Christian , Jude Julian , Wieshofer Corinna , Rescheneder Philipp , Lipp Jesse J. , Herzog Veronika A. , Reichholf Brian , Cisneros David A. , Hoffmann Thomas , Schlapansky Moritz F. , Bhat Pooja , von Haeseler Arndt , Köcher Thomas , Obenauf Anna C. , Popow Johannes , Ameres Stefan L. , Zuber Johannes
Published: April 2018

Profiling transcription—a SLAM dunk

Identification of the direct target genes of transcription factors could shed light on how healthy cells become malignant. Muhar
et al.
applied a modified version of a transcript-mapping method called SLAM-seq to identify the target genes of two transcriptional regulators of major interest in cancer research (see the Perspective by Sabò and Amati). The MYC oncoprotein selectively activates transcription of just a few genes, primarily those involved in basic cell metabolism. In contrast, BRD4, a bromodomain-containing protein that is being targeted for cancer therapy, activates transcription of many genes.

Science
, this issue p.
800
; see also p.
713
Cryo-EM structure of a herpesvirus capsid at 3.1 Å
Authors: Yuan Shuai , Wang Jialing , Zhu Dongjie , Wang Nan , Gao Qiang , Chen Wenyuan , Tang Hao , Wang Junzhi , Zhang Xinzheng , Liu Hongrong , Rao Zihe , Wang Xiangxi
Published: April 2018

Focusing in on herpesvirus

The herpesvirus family includes herpes simplex virus type 1 (HSV-1), which causes cold sores, and type 2 (HSV-2), which causes genital herpes. Herpesviruses comprise a large DNA genome enclosed in a large and complex protein cage called a capsid (see the Perspective by Heldwein). Dai and Zhou used electron microscopy to determine a high-resolution structure of the HSV-1 capsid bound to the tegument proteins that occupy the space between the capsid and the nuclear envelope. The structure suggests how these components may play a role in viral transport. Yuan
et al.
describe a higher-resolution structure of an HSV-2 capsid, providing insight into how the shell assembles and is stabilized.

Science
, this issue p.
eaao7298
, p.
eaao7283
; see also p.
34
Single-cell transcriptomics of the mouse kidney reveals potential cellular targets of kidney disease
Authors: Park Jihwan , Shrestha Rojesh , Qiu Chengxiang , Kondo Ayano , Huang Shizheng , Werth Max , Li Mingyao , Barasch Jonathan , Suszták Katalin
Published: April 2018

Touring the kidney, cell by cell

Our kidneys play a critical role in keeping us healthy, a fact of which we are reminded several times each day. This organ's cellular complexity has hindered progress in understanding the mechanisms underlying chronic kidney disease, which affects 10% of the world's population. Using single-cell transcriptional profiling, Park
et al.
produced a comprehensive cell atlas of the healthy mouse kidney (see the Perspective by Humphreys). An unexpected cell type in the collecting duct appears to be a transitional state between two known cell types. The transition from one cell type to the other is regulated by the Notch signaling pathway and is associated with metabolic acidosis. The authors also find that genetically distinct kidney diseases with common clinical features share common cellular origins.

Science
, this issue p.
758
; see also p.
709
Enzymatic construction of highly strained carbocycles
Authors: Chen Kai , Huang Xiongyi , Kan S. B. Jennifer , Zhang Ruijie K. , Arnold Frances H.
Published: April 2018

Double rings made with heme

Cyclic organic structures with adjacent three-carbon rings—bicyclobutanes—are useful starting materials for chemical and materials synthesis owing to their extreme ring strain. Constructing these molecules is a challenging task for organic chemists, especially if a single stereoisomer is desired. Chen
et al.
engineered a heme-containing enzyme to catalyze sequential carbene insertion reactions using an alkyne substrate. Starting with an enzyme that could only catalyze a single carbene insertion, a series of mutations led to variants that catalyzed efficient, stereoselective production of bicyclobutanes. By using a less reactive alkyne substrate and screening more variants with active site mutations, the authors found enzymes that stop at either enantiomer of the intermediate cyclopropene.

Science
, this issue p.
71
Testing international education assessments
Authors: Singer Judith D. , Braun Henry I.
Published: April 2018

Rankings get headlines, but often mislead
Catalytic enantioselective Minisci-type addition to heteroarenes
Authors: Proctor Rupert S. J. , Davis Holly J. , Phipps Robert J.
Published: April 2018

Light and acid steer a radical addition

So-called Minisci reactions have been used for decades in pharmaceutical and agrochemical synthesis to make carbon-carbon bonds. The reactions link carbon radicals to the carbon centers adjacent to nitrogen in pyridine rings. Proctor
et al.
devised a method to steer these reactions to just one of two possible mirror-image products. To make the radicals, they prepared derivatives of widely available amino acids and then activated them with an iridium photocatalyst. At the same time, a chiral phosphoric acid catalyst was used to activate the pyridine and bias the reaction geometry.

Science
, this issue p.
419
Microplastics research—from sink to source
Authors: Rochman Chelsea M.
Published: April 2018

Microplastics are ubiquitous not just in the ocean but also on land and in freshwater systems
Up close with herpesviruses
Authors: Heldwein Ekaterina E.
Published: April 2018

Two high-resolution structures reveal how ∼3000 proteins are arranged in the herpes simplex virus capsid
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

Polymyxins 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.
A Consistent and Predictable Commercial Broiler Chicken Bacterial Microbiota in Antibiotic-Free Production Displays Strong Correlations with Performance
Authors: Johnson Timothy J. , Youmans Bonnie P. , Noll Sally , Cardona Carol , Evans Nicholas P. , Karnezos T. Peter , Ngunjiri John M. , Abundo Michael C. , Lee Chang-Won
Published: April 2018

Defining the baseline bacterial microbiome is critical to understanding its relationship with health and disease. In broiler chickens, the core microbiome and its possible relationships with health and disease have been difficult to define, due to high variability between birds and flocks. Presented here are data from a large, comprehensive microbiota-based study in commercial broilers. The primary goals of this study included understanding what constitutes the core bacterial microbiota in the broiler gastrointestinal, respiratory, and barn environments; how these core players change across age, geography, and time; and which bacterial taxa correlate with enhanced bird performance in antibiotic-free flocks. Using 2,309 samples from 37 different commercial flocks within a vertically integrated broiler system and metadata from these and an additional 512 flocks within that system, the baseline bacterial microbiota was defined using 16S rRNA gene sequencing. The effects of age, sample type, flock, and successive flock cycles were compared, and results indicate a consistent, predictable, age-dependent bacterial microbiota, irrespective of flock. The tracheal bacterial microbiota of broilers was comprehensively defined, andLactobacilluswas the dominant bacterial taxon in the trachea. Numerous bacterial taxa were identified, which were strongly correlated with broiler chicken performance across multiple tissues. While many positively correlated taxa were identified, negatively associated potential pathogens were also identified in the absence of clinical disease, indicating that subclinical dynamics occur that impact performance. Overall, this work provides necessary baseline data for the development of effective antibiotic alternatives, such as probiotics, for sustainable poultry production.

IMPORTANCEMultidrug-resistant bacterial pathogens are perhaps the greatest medical challenge we will face in the 21st century and beyond. Antibiotics are necessary in animal production to treat disease. As such, animal production is a contributor to the problem of antibiotic resistance. Efforts are underway to reduce antibiotic use in animal production. However, we are also challenged to feed the world's increasing population, and sustainable meat production is paramount to providing a safe and quality protein source for human consumption. In the absence of antibiotics, alternative approaches are needed to maintain health and prevent disease, and probiotics have great promise as one such approach. This work paves the way for the development of alternative approaches to raising poultry by increasing our understandings of what defines the poultry microbiome and of how it can potentially be modulated to improve animal health and performance.
Characterization of the Trehalose Utilization Operon in Streptococcus mutans Reveals that the TreR Transcriptional Regulator Is Involved in Stress Response Pathways and Toxin Production
Authors: Baker J. L. , Lindsay E. L. , Faustoferri R. C. , To T. T. , Hendrickson E. L. , He X. , Shi W. , McLean J. S. , Quivey R. G.
Published: April 2018

Streptococcus mutans
, the organism most frequently associated with the development of dental caries, is able to utilize a diverse array of carbohydrates for energy metabolism. One such molecule is trehalose, a disaccharide common in human foods, which has been recently implicated in enhancing the virulence of epidemic strains of the pathogen
Clostridium difficile
. In this study, mutants with deletions of all three genes in the putative
S. mutans
trehalose utilization operon were characterized, and the genes were shown to be required for wild-type levels of growth when trehalose was the only carbohydrate source provided. Interestingly, the TreR transcriptional regulator appeared to be critical for responding to oxidative stress and for mounting a protective stress tolerance response following growth at moderately acidic pH. mRNA sequencing (RNA-seq) of a
treR
deletion mutant suggested that in
S. mutans
, TreR acts as a trehalose-sensing activator of transcription of the
tre
operon, rather than as a repressor, as described in other species. In addition, deletion of
treR
caused the downregulation of a number of genes involved in genetic competence and bacteriocin production, supporting the results of a recent study linking trehalose and the
S. mutans
competence pathways. Finally, deletion of
treR
compromised the ability of
S. mutans
to inhibit the growth of the competing species
Streptococcus gordonii
and
Lactococcus lactis
. Taking the results together, this study solidifies the role of the
S. mutans tre
operon in trehalose utilization and suggests novel functions for the TreR regulator, including roles in the stress response and competitive fitness.

IMPORTANCE
S. mutans
is the primary etiologic agent of dental caries, which globally is the most common chronic disease.
S. mutans
must be able to outcompete commensal organisms in its dental plaque niche in order to establish persistence and pathogenesis. To that end,
S. mutans
metabolizes a diverse array of carbohydrates to generate acid and impede its acid-sensitive neighbors. Additionally,
S. mutans
utilizes quorum signaling through genetic competence-associated pathways to induce production of toxins to kill its rivals. This study definitively shows that the
S. mutans
trehalose utilization operon is required for growth in trehalose. Furthermore, this study suggests that the
S. mutans
TreR transcriptional regulator has a novel role in virulence through regulation of genes involved in genetic competence and toxin production.