bluuebunny/crossref_metadata_2025_split huggingface dataset:
Service operations: what have we learned?
Authors: Victorino Liana , Field Joy M. , Buell Ryan W. , Dixon Michael J. , Meyer Goldstein Susan , Menor Larry J. , Pullman Madeleine E. , Roth Aleda V. , Secchi Enrico , Zhang Jie J. 
Published: January 2018

PurposeThe purpose of this paper is to identify research themes in service operations that have great potential for exciting and innovative conceptual and empirical work. To frame these research themes, the paper provides a systematic literature review of operations articles published in theJournal of Service Management(JOSM). The thorough review of published work inJOSMand proposed research themes are presented in hopes that they will inspire impactful research on service operations. These themes are further developed in a companion paper, “Service operations: what’s next?” (Fieldet al., 2018).Design/methodology/approachTheJOSMService Operations Expert Research Panel conducted a Delphi study to generate research themes where leading-edge research on service operations is being done or has yet to be done. Nearly 700 articles published inJOSMfrom its inception through 2016 were reviewed and classified by discipline focus. The subset of service operations articles was then further categorized according to the eight identified research themes plus an additional category that primarily represented traditional manufacturing approaches applied in service settings.FindingsFrom the Delphi study, the following key themes emerged: service supply networks, evaluating and measuring service operations performance, understanding customer and employee behavior in service operations, managing servitization, managing knowledge-based service contexts, managing participation roles and responsibilities in service operations, addressing society’s challenges through service operations, and the operational implications of the sharing economy. Based on the literature review, approximately 20 percent of the published work inJOSMis operations focused, with earlier articles predominantly applying traditional manufacturing approaches in service settings. However, the percentage of these traditional types of articles has been steadily decreasing, suggesting a trend toward dedicated research frameworks and themes that are unique to the design and management of services operations.Originality/valueThe paper presents key research themes for advancing conceptual and empirical research on service operations. Additionally, a review of the past and current landscape of operations articles published inJOSMoffers an understanding of the scholarly conversation so far and sets a foundation from which to build future research.
Pearl millet processing: a review
Authors: Rani Savita , Singh Rakhi , Sehrawat Rachna , Kaur Barjinder Pal , Upadhyay Ashutosh 
Published: January 2018

Purpose
Pearl millet (Pennisetum glaucum) is a rich source of nutrients as compared to the major cultivated cereal crops. However, major factors which limit its utilization are the presence of anti-nutritional factors (phytate, tannins and polyphenols) which lower availability of minerals and poor keeping quality because of higher lipase activity. Therefore, this paper aims to focus on the impact of different processing methods on the nutrient composition and anti-nutritional components of pearl millet.

Design/methodology/approach
This is a literature review study from 1983 to 2017, focusing on studies related to pearl millet processing and their effectiveness in the enrichment of nutritional value through reduction of anti-nutritional compounds.

Findings
From the literature reviewed, pearl millet processing through various methods including milling, malting, fermentation, blanching and acid as well as heat treatments were found to be effective in achieving the higher mineral digestibility, retardation of off flavor, bitterness as well as rancidity problems found during storage of flour.

Originality/value
Through this review paper, possible processing methods and their impact on the nutrient and anti-nutrient profile of pearl millet are discussed after detailed studied of literature from journal articles and thesis.
Beet and orange mixed juices added with Lactobacillus acidophilus
Authors: Porto Maria Rita Alaniz , Okina Vivian Sayuri , Pimentel Tatiana Colombo , Garcia Sandra , Prudencio Sandra Helena 
Published: January 2018

Purpose
The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture.

Design/methodology/approach
Two formulations of probiotic beet and orange mixed juices (1:1 e 1:2 v/v) were prepared, stored at 4°C for 28 days and were evaluated for probiotic survival, physicochemical stability, antioxidant activity and sensory acceptance. The probiotic culture was added in a lyophilized form and was not propagated in culture media or juice.

Findings
Physicochemical characteristics (pH, titratable acidity, total soluble solids and color) and antioxidant activity showed no undesirable alterations during storage. The number of probiotics followed established minimum requirement for probiotic foods (109 CFU/200mL) during the 28 days of storage. The juices showed good sensory acceptance and purchase intention, especially regarding the color of the product.

Practical implications
The beet and orange mixed juices are suitable carriers for L. acidophilus with a shelf life of at least 28 days at 4°C.

Originality/value
Direct addition of the probiotic culture could result in high probiotic survival in mixed juices, dispensing the propagation step.
Decolorization of reactive dyes, Part I: eco-friendly approach of reactive dye effluents decolorization using cationized sugarcane bagasse
Authors: Aly Amal A. , Mahmoud Safia A. , El-Apasery Morsy Ahmed 
Published: January 2018

Purpose
This paper aims to decolorize the effluents of textile Reactive Orange 5 and Reactive Red 195 dyes by using cationized sugarcane bagasse.

Design/methodology/approach
Cationized sugarcane bagasse was prepared and used as an adsorbent for both reactive and hydrolyzed reactive dyes. Characterization of the sugarcane bagasse structure resulted by cationization was monitored using Fourier transform–infrared, while morphologically was detected using scanning electron microscopy and X-ray powder diffraction.

Findings
The maximum adsorption capacities are 805, 1,664, 1,772 and 1,596 mg/g for Hydrolyzed Red 195, Hydrolyzed Orange 5, Reactive Red 195 and Reactive Orange 5 dyes, respectively.

Research limitations/implications
Factors affecting the percentage of dye removal were optimized on different parameters such as adsorbent dose and treatment time. The data were discussed using the Langmuir and Freundlich Models of adsorption.

Practical implications
The reuse of hydrolyzed reactive dyebaths gives reasonably good fastness properties on nylon fabrics.

Social implications
The study has enabled the production of an eco-friendly and less expensive method of reactive dye effluent decolorization.

Originality/value
The study provides a potentially simple approach to decolorize dye effluents of Reactive Orange 5, Red 195 dyes and also the reuse of hydrolyzed reactive dyebaths for dyeing nylon.
Crystal Structure of NisI in a Lipid-Free Form, the Nisin Immunity Protein, from Lactococcus lactis
Authors: Jeong Jin Hee , Ha Sung Chul 
Published: January 2018

ABSTRACT

Nisin is a lantibiotic, a member of a family of polypeptides containing lanthionine with antimicrobial activity. Nisin-producing microorganisms require immunity proteins for self-protection from nisin itself.
Lactococcus lactis
, a microorganism that synthesizes nisin, has an integral NisFEG ABC transporter and an NisI lipoprotein that function in nisin immunity. Here, we present the crystal structure of the full length of NisI
22-C
, a lipid-free form of NisI, determined at 1.9-Å resolution. As with the nuclear magnetic resonance (NMR) structures of the N- and C-terminal domains of NisI, NisI
22-C
is composed of N- and C-terminal domains, both of which display a fold similar to that found in SpaI, a lipoprotein with immunity against subtilin in
Bacillus subtilis
. The full-length structure of NisI
22-c
reveals a large, deep cleft by the interdomain association, one side of which is occupied by the residues important for immunity. Opposite the cleft, a shallow groove is found where nisin-interacting residues are distributed in the periphery composed of the C-terminal negative patch. Based on a sulfate ion found in the large and deep cleft, a model of NisI in complex with a farnesyl diphosphate backbone of lipid II is proposed, suggesting a mechanism for increasing the chances of encountering nisin.
Capsule Prolongs Survival of Streptococcus pneumoniae during Starvation
Authors: Hamaguchi Shigeto , Zafar M. Ammar , Cammer Michael , Weiser Jeffrey N. 
Published: January 2018

ABSTRACT

Person-to-person transmission of
Streptococcus pneumoniae
(the pneumococcus) may occur via environmental sources in close contact with carriers. Pneumococcal polysaccharide capsules, the determinant of serotype (or type), are heterogeneous in structure and amount, and these differences affect rates of transmission. In this study, we examined the contribution of capsule and its variations to the maintenance of pneumococcal viability under starvation conditions.
S. pneumoniae
retained its ability to colonize infant mice even after incubation for 24 h in phosphate-buffered saline at 25°C. The expression of capsule by the
cps
locus prolonged survival under these and other nutrient-poor conditions. Analysis of capsule-switch constructs showed that strain-to-strain differences in survival were due to capsule type rather than genetic background. The addition of glucose was sufficient to rescue the survival defect of the capsule-deficient derivative, demonstrating that in the absence of capsule, survival depends upon nutrient availability. During starvation, there was a decrease in capsule size and amount of capsular polysaccharide that was dependent on bacterial viability and the presence of the
cps
locus. These observations suggest that pneumococci catabolize their own capsular polysaccharide using the genes involved in its biosynthesis to maintain viability when other carbon sources are unavailable. Our findings describe a new role of the pneumococcal capsule: the prolongation of viability under nutrient-limiting conditions as would be encountered during periods when the organism is between hosts.
Translocation through the Conjugative Type IV Secretion System Requires Unfolding of Its Protein Substrate
Authors: Trokter Martina , Waksman Gabriel 
Published: January 2018

ABSTRACT
Bacterial conjugation, a mechanism of horizontal gene transfer, is the major means by which antibiotic resistance spreads among bacteria (1, 2). Conjugative plasmids are transferred from one bacterium to another through a type IV secretion system (T4SS) in the form of single-stranded DNA covalently attached to a protein called relaxase. The relaxase is fully functional both in a donor cell (prior to conjugation) and recipient cell (after conjugation). Here, we demonstrate that the protein substrate has to unfold for efficient translocation through the conjugative T4SS. Furthermore, we present various relaxase modifications that preserve the function of the relaxase but block substrate translocation. This study brings us a step closer to deciphering the complete mechanism of T4SS substrate translocation, which is vital for the development of new therapies against multidrug-resistant pathogenic bacteria.

IMPORTANCE
Conjugation is the principal means by which antibiotic resistance genes spread from one bacterium to another (1, 2). During conjugation, a covalent complex of single-stranded DNA and a protein termed relaxase is transported by a type IV secretion system. To date, it is not known whether the relaxase requires unfolding prior to transport. In this report, we use functional assays to monitor the transport of wild-type relaxase and variants containing unfolding-resistant domains and show that these domains reduce conjugation and protein transport dramatically. Mutations that lower the free energy of unfolding in these domains do not block translocation and can even promote it. We thus conclude that the unfolding of the protein substrate is required during transport.
Characterization of Conserved and Novel Septal Factors in Mycobacterium smegmatis
Authors: Wu Katherine J. , Zhang Jenna , Baranowski Catherine , Leung Vivian , Rego E. Hesper , Morita Yasu S. , Rubin Eric J. , Boutte Cara C. 
Published: January 2018

ABSTRACT

Septation in bacteria requires coordinated regulation of cell wall biosynthesis and hydrolysis enzymes so that new septal cross-wall can be appropriately constructed without compromising the integrity of the existing cell wall. Bacteria with different modes of growth and different types of cell wall require different regulators to mediate cell growth and division processes. Mycobacteria have both a cell wall structure and a mode of growth that are distinct from well-studied model organisms and use several different regulatory mechanisms. Here, using
Mycobacterium smegmatis
, we identify and characterize homologs of the conserved cell division regulators FtsL and FtsB, and show that they appear to function similarly to their homologs in
Escherichia coli
. We identify a number of previously undescribed septally localized factors which could be involved in cell wall regulation. One of these, SepIVA, has a DivIVA domain, is required for mycobacterial septation, and is localized to the septum and the intracellular membrane domain. We propose that SepIVA is a regulator of cell wall precursor enzymes that contribute to construction of the septal cross-wall, similar to the putative elongation function of the other mycobacterial DivIVA homolog, Wag31.

IMPORTANCE
The enzymes that build bacterial cell walls are essential for cell survival but can cause cell lysis if misregulated; thus, their regulators are also essential. The number and nature of these regulators is likely to vary in bacteria that grow in different ways. The mycobacteria are a genus that have a cell wall whose composition and construction vary greatly from those of well-studied model organisms. In this work, we identify and characterize some of the proteins that regulate the mycobacterial cell wall. We find that some of these regulators appear to be functionally conserved with their structural homologs in evolutionarily distant species such as
Escherichia coli
, but other proteins have critical regulatory functions that may be unique to the actinomycetes.
Cyanide Production by
Chromobacterium piscinae
Shields It from
Bdellovibrio bacteriovorus
HD100 Predation
Authors: Mun Wonsik , Kwon Heeun , Im Hansol , Choi Seong Yeol , Monnappa Ajay K. , Mitchell Robert J. 
Published: January 2018

ABSTRACT

Predation of
Chromobacterium piscinae
by
Bdellovibrio bacteriovorus
HD100 was inhibited in dilute nutrient broth (DNB) but not in HEPES. Experiments showed that the effector responsible was present in the medium, as cell-free supernatants retained the ability to inhibit predation, and that the effector was not toxic to
B. bacteriovorus
. Violacein, a bisindole secondary metabolite produced by
C. piscinae
, was not responsible. Further characterization of
C. piscinae
found that this species produces sufficient concentrations of cyanide (202 µM) when grown in DNB to inhibit the predatory activity of
B. bacteriovorus
, but that in HEPES, the cyanide concentrations were negligible (19 µM). The antagonistic role of cyanide was further confirmed, as the addition of hydroxocobalamin, which chelates cyanide, allowed predation to proceed. The activity of cyanide against
B. bacteriovorus
was found to be twofold, depending on the life cycle stage of this predator. For the attack-phase predatory cells, cyanide caused the cells to lose motility and tumble, while for intraperiplasmic predators, development and lysis of the prey cell were halted. These findings suggest that cyanogenesis in nature may be employed by the bacterial strains that produce this compound to prevent and reduce their predation by
B. bacteriovorus
.

IMPORTANCE
Bacterial predators actively attack, kill, and enter the periplasm of susceptible Gram-negative bacteria, where they consume the prey cell components. To date, the activity of
B. bacteriovorus
HD100 has been demonstrated against more than 100 human pathogens. As such, this strain and others are being considered as potential alternatives or supplements to conventional antibiotics. However, the production of secondary metabolites by prey bacteria is known to mitigate, and even abolish, predation by bacterivorous nematodes and protists. With the exception of indole, which was shown to inhibit predation, the effects of bacterial secondary metabolites on
B. bacteriovorus
and its activities have not been considered. Consequently, we undertook this study to better understand the mechanisms that bacterial strains employ to inhibit predation by
B. bacteriovorus
HD100. We report here that cyanogenic bacterial strains can inhibit predation and show that cyanide affects both attack-phase predators and those within prey, i.e., in the bdelloplast.
Extracellular DNA and Type IV Pilus Expression Regulate the Structure and Kinetics of Biofilm Formation by Nontypeable
Haemophilus influenzae
Authors: Das Jayajit , Mokrzan Elaine , Lakhani Vinal , Rosas Lucia , Jurcisek Joseph A. , Ray William C. , Bakaletz Lauren O. 
Published: January 2018

ABSTRACT

Biofilms formed in the middle ear by nontypeable
Haemophilus influenzae
(NTHI) are central to the chronicity, recurrence, and refractive nature of otitis media (OM). However, mechanisms that underlie the emergence of specific NTHI biofilm structures are unclear. We combined computational analysis tools and
in silico
modeling rooted in statistical physics with confocal imaging of NTHI biofilms formed
in vitro
during static culture in order to identify mechanisms that give rise to distinguishing morphological features. Our analysis of confocal images of biofilms formed by NTHI strain 86-028NP using pair correlations of local bacterial densities within sequential planes parallel to the substrate showed the presence of fractal structures of short length scales (≤10 μm). The
in silico
modeling revealed that extracellular DNA (eDNA) and type IV pilus (Tfp) expression played important roles in giving rise to the fractal structures and allowed us to predict a substantial reduction of these structures for an isogenic mutant (Δ
comE
) that was significantly compromised in its ability to release eDNA into the biofilm matrix and had impaired Tfp function. This prediction was confirmed by analysis of confocal images of
in vitro
Δ
comE
strain biofilms. The fractal structures potentially generate niches for NTHI survival in the hostile middle ear microenvironment by dramatically increasing the contact area of the biofilm with the surrounding environment, facilitating nutrient exchange, and by generating spatial positive feedback to quorum signaling.

IMPORTANCE
NTHI is a major bacterial pathogen for OM, which is a common ear infection in children worldwide. Chronic OM is associated with bacterial biofilm formation in the middle ear; therefore, knowledge of the mechanisms that underlie NTHI biofilm formation is important for the development of therapeutic strategies for NTHI-associated OM. Our combined approach using confocal imaging of NTHI biofilms formed
in vitro
and mathematical tools for analysis of pairwise density correlations and agent-based modeling revealed that eDNA and Tfp expression were important factors in the development of fractal structures in NTHI biofilms. These structures may help NTHI survive in hostile environments, such as the middle ear. Our
in silico
model can be used in combination with laboratory or animal modeling studies to further define the mechanisms that underlie NTHI biofilm development during OM and thereby guide the rational design of, and optimize time and cost for, benchwork and preclinical studies.
Expression and Cellular Localization of CXCR4 and CXCL12 in Human Carotid Atherosclerotic Plaques
Authors: Merckelbach Sophie , van der Vorst Emiel , Kallmayer Michael , Rischpler Christoph , Burgkart Rainer , Döring Yvonne , de Borst Gert-Jan , Schwaiger Markus , Eckstein Hans-Henning , Weber Christian , Pelisek Jaroslav 
Published: January 2018

Background and Aims The CXCR4/CXCL12 complex has already been associated with progression of atherosclerosis; however, its exact role is yet unknown. The aim of this study was to analyse the expression and cellular localization of CXCL12 and its receptor CXCR4 in human carotid atherosclerotic plaques.
Methods Carotid plaques (n = 58; 31 stable, 27 unstable, based on histological characterization of plaque morphology) were obtained during carotid endarterectomy, and 10 healthy vessels were used as a control. Expression of cxcr4, cxcr7, cxcl12, ccl2/ccr2 and csf1/csf1r was analysed at mRNA, and level expression of CXCR4, CXCR7 and CXCL12 was analysed at protein level. Cellular localization was determined using consecutive and double immunohistochemical (IHC) staining and microdissection.
Results At mRNA level, cxcr4, cxcr7 and cxcl12 were significantly higher expressed in stable carotid plaques compared with controls (p = 0.011, p < 0.001 and p < 0.001). Cxcl12 mRNA expression was successively augmented toward unstable plaques (p < 0.001). At protein level, CXCR4, CXCR7 and CXCL12 expression was significantly increased in both stable (p = 0.001, p < 0.001 and p = 0.035, respectively) and unstable (p = 0.003, p < 0.001 and p = 0.045, respectively) plaques compared with controls. Using IHC, CXCR4 was particularly localized in macrophages and small neovessels. Microdissection confirmed strongest expression of cxcr4 in macrophages within atherosclerotic plaques. Leukocytes and smooth muscle cells showed cxcr4 expression as well. For cxcl12, only microdissected areas with macrophages were positive.
Conclusion Expression of CXCR4 and CXCL12 was significantly increased in both stable and unstable carotid atherosclerotic plaques compared with healthy vessels, both at mRNA and protein level. CXCR4 and CXCL12 were localized particularly in macrophages.