bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive capacity limits are remediated by practice-induced plasticity between the Putamen and Pre-Supplementary Motor Area
Authors: Garner K.G. , Garrido M.I. , Dux P.E.
Published: March 2019

Humans show striking limitations in information processing when multitasking, yet can modify these limits with practice. Such limitations have been linked to a frontal-parietal network, but recent models of decision-making implicate a striatal-cortical network. We adjudicated these accounts by investigating the circuitry underpinning multitasking in 100 individuals and the plasticity caused by practice. We observed that multitasking costs, and their practice induced remediation, are best explained by modulations in information transfer between the striatum and the cortical areas that represent stimulus-response mappings. Specifically, our results support the view that multitasking stems at least in part from taxation in information sharing between the putamen and pre-supplementary motor area (pre-SMA). Moreover, we propose that modulations to information transfer between these two regions leads to practice-induced improvements in multitasking.

Significance statement

Humans show striking limitations in information processing when multitasking, yet can modify these limits with practice. Such limitations have been linked to a frontal-parietal network, but recent models of decision-making implicate a striatal-cortical network. We adjudicated these accounts by investigating the circuitry underpinning multitasking in 100 individuals and the plasticity caused by practice. Our results support the view that multitasking stems at least in part from taxation in information sharing between the putamen and pre-supplementary motor area (pre-SMA). We therefore show that models of cognitive capacity limits must consider how subcortical and cortical structures interface to produce cognitive behaviours, and we propose a novel neurophysiological substrate of multitasking limitations.
Streamlined low-input transcriptomics through EASY-RNAseq
Authors: Zhou Yiwen , Xu Hao , Wu Haiyang , Yu Haili , Zhou Peng , Qiu Xin , Zheng Zihan , Chen Qin , Xu Fa , Li Gang , Zhou Jianzhi , Cheng Gang , He Wei , Zou Liyun , Wan Ying
Published: March 2019

High-throughput sequencing for transcriptome profiling is an increasingly accessible and important tool for biological research. However, accurate profiling of small cell populations remains challenging due to issues with gene detection sensitivity and experimental complexity. Here we describe a streamlined RNAseq protocol (EASY RNAseq) for sensitive transcriptome assessment starting from low amount of input materials. EASY RNAseq is technically robust enough for sequencing small pools of homogenous and heterogeneous cells, recovering higher numbers of genes and with a more even expression distribution pattern than other commonly used methods. Application of EASY RNAseq to single human embryos at the 8-cell stage was able to achieve detection of 70% protein-coding genes. This workflow may thus serve as a useful tool for sensitive interrogation of rare cell populations.
Dynamic compression and expansion in a classifying recurrent network
Authors: Farrell Matthew , Recanatesi Stefano , Lajoie Guillaume , Shea-Brown Eric
Published: March 2019

Recordings of neural circuits in the brain reveal extraordinary dynamical richness and high variability. At the same time, dimensionality reduction techniques generally uncover low-dimensional structures underlying these dynamics when tasks are performed. In general, it is still an open question what determines the dimensionality of activity in neural circuits, and what the functional role of this dimensionality in task learning is. In this work we probe these issues using a recurrent artificial neural network (RNN) model trained by stochastic gradient descent to discriminate inputs. The RNN family of models has recently shown promise in revealing principles behind brain function. Through simulations and mathematical analysis, we show how the dimensionality of RNN activity depends on the task parameters and evolves over time and over stages of learning. We find that common solutions produced by the network naturally compress dimensionality, while variability-inducing chaos can expand it. We show how chaotic networks balance these two factors to solve the discrimination task with high accuracy and good generalization properties. These findings shed light on mechanisms by which artificial neural networks solve tasks while forming compact representations that may generalize well.
LonP1 Orchestrates UPRmtand UPRERand Mitochondrial Dynamics to Regulate Heart Function
Authors: Lu Bin , Shangguan Fugen , Huang Dawei , Gong Shiwei , Shi Yingchao , Song Zhiying , Jia Lianqun , Xu Juan , Yan Chaojun , Chen Tongke , Xu Mingjie , Li Yujie , Han Shengnan , Song Nan , Chen Pingyi , Wang Lu , Liu Yongzhang , Huang Xingxu , Suzuki Carolyn K. , Yang Zhongzhou , Yang Guanlin
Published: March 2019

Protein quality control is pivotal to cellular homeostasis and integrity of cardiomyocytes for maintenance of normal heart function. The unfolded protein response (UPR) is an adaptive process to modulate protein quality control in the endoplasmic reticulum (ER) and mitochondria, and is accordingly termed UPRERand UPRmt, respectively. Lon protease (LonP1) is a highly conserved mitochondrial protease to modulate UPRmt, which is involved in regulating metabolism, mitophagy, and stress response. However, whether LonP1 regulates UPRERremains elusive. To investigate the regulation of protein quality control in cardiomyocytes, we generated cardiac-specific LonP1 deletion mice. Our findings show that LonP1 deficiency caused impaired mitochondrial respiratory function and fragmentation. Surprisingly, both UPRERand UPRmtis substantially induced in LonP1-deletion heart suggesting of LonP1 as a novel regulator of UPRER; however, the activation of UPRERoccurs earlier than UPRmtin response to LonP1 deletion. Consequently, cardiac-specific LonP1 deficiency causes aberrant metabolic reprogramming of cardiomyocytes, pathological heart remodeling, as well as impeded heart function. Thus, we uncovered the novel function of LonP1 as an UPRmtmediator, and reciprocal orchestration of UPRmtand UPRERand mitochondrial dynamics regulated by LonP1 in the cardiomyocytes that is critical to maintain heart function, which offers exciting new insights into the potential therapeutic strategy for heart failure.
Pluripotency and the origin of animal multicellularity
Authors: Sogabe Shunsuke , Hatleberg William L. , Kocot Kevin M. , Say Tahsha E. , Stoupin Daniel , Roper Kathrein E. , Fernandez-Valverde Selene L. , Degnan Sandie M. , Degnan Bernard M.
Published: March 2019

The most widely held, but rarely tested, hypothesis for the origin of animals is that they evolved from a unicellular ancestor with an apical cilium surrounded by a microvillar collar that structurally resembled present-day sponge choanocytes and choanoflagellates1–4. Here we test this traditional view of the origin of the animal kingdom by comparing the transcriptomes, fates and behaviours of the three primary sponge cell types – choanocytes, pluripotent mesenchymal archeocytes and epithelial pinacocytes – with choanoflagellates and other unicellular holozoans. Unexpectedly, we find the transcriptome of sponge choanocytes is the least similar to the transcriptomes of choanoflagellates and is significantly enriched in genes unique to either animals or to sponges alone. In contrast, pluripotent archeocytes upregulate genes controlling cell proliferation and gene expression, as in other metazoan stem cells and in the proliferating stages of two closely-related unicellular holozoans, including a colonial choanoflagellate. In the context of the body plan of the sponge, Amphimedon queenslandica, we show that choanocytes appear late in development and are the result of a transdifferentiation event. They exist in a metastable state and readily transdifferentiate into archeocytes, which can differentiate into a range of other cell types. These sponge cell type conversions are similar to the temporal cell state changes that occur in many unicellular holozoans5. Together, these analyses offer no support for the homology of sponge choanocytes and choanoflagellates, nor for the view that the first multicellular animals were simple balls of cells with limited capacity to differentiate. Instead, our results are consistent with the first animal cell being able to transition between multiple states in a manner similar to modern transdifferentiating and stem cells.
Glycosylation of Zika Virus Is Important in Host-Virus Interaction and Pathogenesis
Authors: Routhu Nanda Kishore , Lehoux Sylvain D. , Rouse Emily A. , Bidokhti Mehdi R. M. , Giron Leila B. , Anzurez Alit , Reid St Patrick , Abdel-Mohsen Mohamed , Cummings Richard D. , Byrareddy Siddappa N.
Published: March 2019

Zika virus (ZIKV) is a global public health issue due to its association with severe developmental disorders in infants and neurological disorders in adults. Because ZIKV uses glycosylation of its envelope (E) protein to interact with host cell receptors to facilitate entry, these interactions could also be important for designing therapeutics and vaccines. Due to a lack of information about Asn-linked (N-glycans) on ZIKV E, we analyzed ZIKV E of various strains derived from different cells. ZIKV E proteins are extensively modified with oligomannose-, hybrid- and complex-N-glycans of a highly heterogeneous nature. Host cell-surface glycans correlated strongly with the glycomic features of ZIKV E. Mechanistically, we discovered that ZIKV N-glycans are important in viral pathogenesis, as mannose-specific C-type lectins DC-SIGN and L-SIGN mediate cell entry of ZIKV. Our findings represent the first detailed mapping of N-glycans on ZIKV E of various strains and their functional significance.
RB1 deletion in RB-pathway disrupted cells results in DNA damage and cancer progression
Authors: Marshall Aren E. , Roes Michael V. , Passos Daniel T. , DeWeerd Megan C. , Chaikovsky Andrea C. , Sage Julien , Howlett Christopher J. , Dick Frederick A.
Published: March 2019

Proliferative control in cancer cells is frequently disrupted by mutations in the RB-pathway. Intriguingly, RB1 mutations can arise late in tumorigenesis in cancer cells whose RB-pathway is already compromised by another mutation. In this study, we present evidence for increased DNA damage and instability in CDKN2A silenced cancer cells when RB1 mutations are induced. We generated isogenic RB1 mutant genotypes with CRISPR in a number of cell lines. Cells with even one mutant copy of RB1 have increased basal levels of DNA damage and increased mitotic errors. Elevated levels of reactive oxygen species as well as impaired homologous recombination repair underlie this DNA damage. When xenografted into immune compromised mice RB1 mutant cells exhibit an elevated propensity to seed new tumors in recipient lungs. This study offers evidence that late arising RB1 mutations can facilitate genome instability and cancer progression that are beyond the pre-existing proliferative control deficit.
High-throughput genotyping of a full voltage-gated sodium channel gene via genomic DNA using target capture sequencing and analytical pipeline MoNaS to discover novel insecticide resistance mutations
Authors: Itokawa Kentaro , Yatsu Koji , Sekizuka Tsuyoshi , Maekawa Yoshihide , Komagata Osamu , Sugiura Masaaki , Sasaki Tomonori , Tomita Takashi , Kuroda Makoto , Sawabe Kyoko , Kasai Shinji
Published: March 2019

Insects’ voltage-gated sodium channel (VGSC) is the primary target site of pyrethroid insecticides. Various amino acid substitutions in the VGSC protein are known to confer insecticide resistance and are selected under insecticide pressure. In the genome, theVGSCgene consists of more than 30 exons sparsely distributed across a large genomic region, which often exceeds 100 kbp. Due to this complex genomic structure of geneVGSC, it is usually challenging to genotype full coding nucleotide sequences (CDSs) ofVGSCfrom individual genomic DNA (gDNA). In this study, we designed biotinylated oligonucleotide probes via annotated CDSs ofVGSCof Asian tiger mosquito,Aedes albopictus. The probe set effectively concentrated (>80,000-fold) all targeted regions of geneVGSCfrom pooled barcoded Illumina libraries each constructed from individualA. albopictusgDNAs. The probe set also captured all homologousVGSCCDSs except tiny exons from the gDNA of other Culicinae mosquitos,A. aegyptiandCulex pipienscomplex, with comparable efficiency by virtue of the high conservation ofVGSCat the nucleotide level. Furthermore, we developed an automated bioinformatic analysis pipeline to genotypeVGSCafter capture sequencing—MoNaS (MosquitoNa+channel mutationSearch)—which conducts mapping of reads, variant calling, and variant annotation for nonsynonymous mutations. The proposed method and our bioinformatic tool should facilitate the discovery of novel amino acid variants conferring insecticide resistance on VGSC and population genetics studies on resistance alleles with respect to the origin, selection, and migration of both clinically and agriculturally important insect pests.
Pluripotency factors regulate the onset of Hox cluster activation in the early embryo
Authors: Lopez-Jimenez Elena , de Aja Julio Sainz , Badia-Careaga Claudio , Barral Antonio , Rollan Isabel , Rouco Raquel , Santos Elisa , Tiana María , Victorino Jesus , Sanchez-Iranzo Hector , Acemel Rafael D , Torroja Carlos , Adan Javier , Andres-Leon Eduardo , Gomez-Skarmeta Jose Luis , Giovinazzo Giovanna , Sanchez-Cabo Fatima , Manzanares Miguel
Published: March 2019

Pluripotent cells are a transient population present in the early mammalian embryo dependent on transcription factors, such as OCT4 and NANOG, which maintain pluripotency while simultaneously suppressing lineage specification. Interestingly, these factors are not exclusive to uncommitted cells, but are also expressed during early phases of differentiation. However, their role in the transition from pluripotency to lineage specification is largely unknown. Using genetic models for controlledOct4orNanogexpression during postimplantation stages, we found that pluripotency factors play a dual role in regulating key lineage specifiers, initially repressing their expression and later being required for their proper activation. We show that the HoxB cluster is coordinately regulated in this way by OCT4 binding sites located at the 3’ end of the cluster. Our results show that core pluripotency factors are not limited to maintaining the pre-committed epiblast, but are also necessary for the proper deployment of subsequent developmental programs.
Dopaminergic signalling is necessary, but not sufficient for cued fear memory destabilisation
Authors: Flavell Charlotte R. , Lee Jonathan L. C.
Published: March 2019

Pharmacological targeting of memory reconsolidation is a promising therapeutic strategy for the treatment of fear memory-related disorders. However, the success of reconsolidation-based approaches depends upon the effective destabilisation of the fear memory by memory reactivation. Here, we show that the nootropic nefiracetam stimulates tone fear memory destabilisation to facilitate reconsolidation disruption by the glucocorticoid receptor antagonist mifepristone. Moreover, the enhancing effect of nefiracetam was dependent upon dopamine D1 receptor activation, although direct D1 receptor agonism was not sufficient to facilitate destabilisation. Finally, while the combined treatment with nefiracetam and mifepristone did not confer fear-reducing effects under conditions of extinction learning, there was some evidence that mifepristone reduces fear expression irrespective of memory reactivation parameters. Therefore, the use of combination pharmacological treatment to stimulate memory destabilisation and impair reconsolidation has potential therapeutic benefits, without risking a maladaptive increase of fear.
Neph/Nephrin-like adhesion and tissue level pulling forces regulate cell intercalation during Drosophila retina development
Authors: Blackie Laura , Tozluoglu Melda , Trylinski Mateusz , Walther Rhian F. , Mao Yanlan , Schweisguth François , Pichaud Franck
Published: March 2019

Intercalation between neighboring cells contributes to shaping epithelial tissues and is regulated by the contractile actomyosin cytoskeleton. While intercalation typically occurs over minutes, instances of much slower cell intercalation have been reported during organogenesis. This is observed, for example, for the four glial-like cone cells (CC) that intercalate during Drosophila retinal patterning. Here we show that Myosin-II activity in the CCs is largely dispensable for their intercalation. Instead, we find that differential activity of the Notch-signaling pathway within the CC quartet regulates intercalation, which also depends on the cell adhesion proteins Roughest and Hibris. In addition, mathematical modeling predicts that forces external to the intercalating CC quartet are necessary for intercalation. Consistent with this prediction we show that the surrounding primary pigment cells are under significant contractile tension. Altogether, our work elucidates a novel mode of cell intercalation that relies on Neph/Nephrin-like adhesion and forces external to the intercalating cells.
Lifespan trajectories and relationships to memory of the macro- and microstructure of the anterior and posterior hippocampus – a longitudinal multi-modal imaging study
Authors: Langnes Espen , Sneve Markus H. , Sederevicius Donatas , Amlien Inge K. , Walhovd Kristine B , Fjell Anders M
Published: March 2019

There is evidence for a hippocampal long axis anterior-posterior (AP) differentiation in memory processing, which may have implications for the changes in episodic memory performance typically seen across development and aging. The hippocampal formation shows substantial structural changes with age, but the lifespan trajectories of hippocampal sub-regions along the AP axis are not established. The aim of the present study was to test whether the micro- and macro-structural age-trajectories of the anterior (aHC) and posterior (pHC) hippocampus are different. In a single-center longitudinal study, 1790 cognitively healthy participants, 4.1-93.4 years of age, underwent a total of 3367 MRI examinations and 3033 memory tests sessions over 1-6 time points, spanning an interval up to 11.1 years. T1-weighted scans were used to estimate the volume of aHC and pHC, and diffusion tensor imaging to measure mean diffusion (MD) within each region. We found that the macro- and microstructural lifespan-trajectories of aHC and pHC were clearly distinguishable, with partly common and partly unique variance shared with age. aHC showed a protracted period of microstructural development, while pHC microstructural development as indexed by MD was more or less completed in early childhood. In contrast, pHC showed larger unique aging-related changes. A similar aHC – pHC difference was observed for volume, although not as evident as for microstructure. All sub-regions showed age-dependent relationships to episodic memory function. For aHC micro- and macrostructure, the relationships to verbal memory performance varied significantly with age, being stronger among the older participants. Future research should disentangle the relationship between these structural properties and different memory processes – encoding vs. retrieval in particular – across the lifespan.
Spatial co-fragmentation pattern of cell-free DNA recapitulatesin vivochromatin organization and identifies tissues-of-origin
Authors: Liu Yaping , Liu Tzu-Yu , Weinberg David E. , White Brandon W. , De La Torre Chris J. , Tan Catherine L. , Schmitt Anthony D. , Selvaraj Siddarth , Tran Vy , Laurent Louise C. , Cabel Luc , Bidard François-Clément , Putcha Girish , Haque Imran S.
Published: March 2019

Three-dimensional chromatin organization varies across cell types and is essential for gene regulation. However, current technologies are unable to assessin vivogenome-wide chromatin organization non-invasively. Here we show that distant correlations in the fragment length of cell-free DNA (cfDNA) recapitulate three-dimensional chromatin organization. The inferred organization is highly concordant with that measured by Hi-C in white blood cells from healthy donors, and is not explained by technical bias or sequence composition. Furthermore, the inferred organization reflects different genomic organization in the various cell types contributing to cfDNA, allowing identification and quantification of tissues of origin. This approach is concordant with previous methods, but with more complete representations of cfDNA. Our results, demonstrated in cfDNA from healthy individuals and cancer patients, may enable noninvasive monitoring ofin vivogenome organization and accurate quantification of cell death in different clinical conditions.
Cue-induced effects on decision-making distinguish subjects with gambling disorder from healthy controls
Authors: Genauck Alexander , Andrejevic Milan , Brehm Katharina , Matthis Caroline , Heinz Andreas , Weinreich André , Kathmann Norbert , Romanczuk-Seiferth Nina
Published: March 2019

While an increased impact of cues on decision-making has been associated with substance dependence, it is yet unclear whether this is also a phenotype of non-substance related addictive disorders, such as gambling disorder. To better understand the basic mechanisms of impaired decision-making in addiction, we investigated whether cue-induced changes in decision-making could distinguish gambling disorder (GD) from healthy control (HC) subjects. We expected that cue-induced changes in gamble acceptance and specifically in loss aversion would distinguish GD from HC subjects.

30 GD subjects and 30 matched HC subjects completed a mixed gambles task where gambling and other emotional cues were shown in the background. We used machine learning and classification to carve out the importance of cue-dependency of decision-making and of loss aversion for distinguishing GD from HC subjects.

Cross-validated classification yielded an area under the receiver operating curve (AUC-ROC) of 68.9% (p=0.002). Applying the classifier to an independent sample yielded an AUC-ROC of 65.0% (p=0.047). As expected, the classifier used cue-induced changes in gamble acceptance to distinguish GD from HC. Especially increased gambling during the presentation of gambling cues was characteristic of GD subjects. However, unexpectedly, cue-induced changes in loss aversion were irrelevant for distinguishing GD from HC subjects. To our knowledge, this is the first study to investigate the classificatory power of addiction-relevant behavioral task parameters when distinguishing GD from HC subjects. The results indicate that cue-induced changes in decision-making are a characteristic feature of addictive disorders, independent of a substance of abuse.
siRNA containing a unique 5-nucleotide motif acts as a quencher of IFI16-mediated innate immune response
Authors: Sui Hongyan , Yang Jun , Hu Xiaojun , Chen Qian , Imamichi Tomozumi
Published: March 2019

We previously reported that small interfering RNA (siRNA) enhances DNA or DNA virus mediated-interferon (IFN)-λ1 induction through retinoic acid-inducible gene I (RIG-I) and interferon gamma-inducible protein 16 (IFI16) crosstalk-signalling pathway. Here we provide further evidence of a new role for siRNA. siRNA containing a 5-nucleotide (nt) motif sequence suppresses DNA-mediated IFNs and inflammatory cytokines. We determined that motif siRNA inhibits the induction when the motif is located at the 3’ or 5’-terminus of siRNA. Using THP1-Lucia ISG cells with various DNA stimulants, it is demonstrated that motif siRNA inhibits DNA or DNA virus but not RNA virus-mediated signaling. Motif siRNA specifically interrupts IFI16 binding to DNA and has 2.5-fold higher affinity to IFI16 than that of siRNA without the motif. Collectively, these findings may shed lights on a novel function of siRNA with the 5-nt motif as a quencher of innate immunity and facilitate the development of potential therapeutics to treat diseases in which this pathway is dysregulated.
Mannitol ingestion causes concentration-dependent, sex-specific mortality in adults of the fruit fly (Drosophila melanogaster)
Authors: Fiocca Katherine , Barrett Meghan , Waddell Edward A. , McNair Cheyenne , O’Donnell Sean , Marenda Daniel R.
Published: March 2019

Mannitol, a sugar alcohol used in commercial food products, induced sex-specific mortality in the fruit flyDrosophila melanogasterwhen ingested at a single concentration (1M), and female mortality was greater than male mortality. We hypothesized that sex differences in energy needs, related to reproductive costs, contribute to increased mortality in females compared to males. To test for the effects of reproductive costs, we compared longevity to 21 days of actively mating and non-mating flies fed various concentrations of mannitol. We also asked whether mannitol-induced mortality was concentration-dependent for both males and females, and if mannitol’s sex-specific effects were consistent across concentrations. Females and males both showed concentration-dependent increases in mortality, but female mortality was consistently higher at all concentrations above 0.75M. Fly longevity to 21 days decreased further for both sexes when housed in mixed sex vials (as compared to single sex vials), suggesting the increased energetic demands of reproduction for both sexes may increase ingestion of mannitol. Mannitol fed to larvae did not alter emerging adult sex ratios, suggesting that sex-specific mortality due to mannitol occurs only in adults.
A pleiotropic role for FGF signaling in mammary gland stromal fibroblasts
Authors: Koledova Zuzana , Sumbal Jakub
Published: March 2019

Fibroblast growth factor (FGF) signaling is crucial for mammary gland development. While multiple roles for FGF signaling in the epithelium were described, the function of FGF signaling in mammary stroma has not been elucidated. In this study, we investigated FGF signaling in mammary fibroblasts. We found that mammary fibroblasts express FGF receptors 1 and 2 and respond to FGF ligands. In particular, FGF2 and FGF9 induce sustained ERK1/2 signaling and promote fibroblast proliferation and migration in 2D. Intriguingly, only FGF2 induces fibroblast migration in 3D extracellular matrix (ECM) through regulation of actomyosin cytoskeleton and promotes force-mediated collagen remodeling by mammary fibroblasts. Moreover, FGF2 regulates production of ECM proteins by mammary fibroblasts, including collagens, fibronectin, osteopontin, and matrix metalloproteinases. Finally, we show that FGF2 signaling in mammary fibroblasts enhances fibroblast-induced branching of mammary epithelium. Our results demonstrate a pleiotropic role for FGF signaling in mammary fibroblasts with implications for regulation of mammary stromal functions and epithelial branching morphogenesis.

Summary statement

FGF signaling in mammary fibroblasts regulates fibroblast proliferation, migration, extracellular matrix production and remodeling, and fibroblast-mediated mammary epithelial branching morphogenesis.
Histochemical Staining of Cell Monolayers for β-Galactosidase
Authors: Kumar Priti , Nagarajan Arvindhan , Uchil Pradeep D.
Published: March 2019

There are several methods for assaying the success of transient transfections. If a plasmid expressing Escherichia coli β-galactosidase was used, then this histochemical staining procedure is simple to perform and yields dependable results. The following method was designed for cells growing in 60-mm culture dishes.
Preparation of dsRNAs for RNAi by In Vitro Transcription
Authors: Li Chengjian , Zamore Phillip D.
Published: March 2019

This is a simple and widely used method for the preparation of dsRNA using a polymerase chain reaction (PCR) template-based, in vitro transcription reaction. The resulting dsRNA is then used to trigger RNAi in an appropriate cell or organism.
Labeling Antibodies Using a Maleimido Dye
Authors: Berg Eric A. , Fishman Jordan B.
Published: March 2019

Fluorophore-maleimide derivatives are effective for labeling sulfhydryl-containing molecules. Maleimide groups react with free thiols at pH 6.5–7.5 forming a covalent bond. Reducing agents should be avoided during the conjugation step. This protocol uses the cross-linker N-succinimidyl S-acetylthioacetate (SATA) to introduce thiol groups on the antibody while maintaining the divalent nature of the antibody. Alternatively, the antibody can be digested and reduced to monovalent Fab fragments, which can then be labeled directly with maleimido derivatives.
Transfected Dendritic Cell Immunizations
Authors: Greenfield Edward A. , DeCaprio James , Brahmandam Mohan
Published: March 2019

Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs). An efficient way of generating antibodies is to introduce antigens of interest into DCs and then inject them into the host. This will result in initiation of an antigen-specific immune response mediated by T-cell immunity. Apoptosis of DCs expressing transgenic proteins results in enhanced immunity through cross-presentation by endogenous DCs in vivo. The major advantage of this technology is prolonged presentation of antigens that are synthesized endogenously and their presentation by both modified DCs as well as endogenous DCs to the immune system of the host.
Lipofection
Authors: Kumar Priti , Nagarajan Arvindhan , Uchil Pradeep D.
Published: March 2019

In the past, cloned DNA was introduced into cultured eukaryotic cells chiefly by biochemical methods using either calcium phosphate or diethylaminoethyl (DEAE)-dextran. Lipid reagents are now preferred because of the high efficiency of transfection that can be obtained and because of the ability of this class of reagents to mediate transfection of all types of nucleic acids into a wide range of cell types.
Readability and word complexity of SERPs snippets and web pages on children’s search queries
Authors: Bilal Dania , Huang Li-Min
Published: March 2019

Purpose

The purpose of this paper is to analyze the readability and level of word complexity of search engine results pages (SERPs) snippets and associated web pages between Google and Bing.

Design/methodology/approach

The authors employed the Readability Test Tool to analyze the readability and word complexity of 3,000 SERPs snippets and 3,000 associated pages in Google and Bing retrieved on 150 search queries issued by middle school children.

Findings

A significant difference was found in the readability of SERPs snippets and associated web pages between Google and Bing. A significant difference was also observed in the number of complex words in snippets between the two engines but not in associated web pages. At the engine level, the readability of Google and Bing snippets was significantly higher than associated web pages. The readability of Google SERPs snippets was at a much higher level than those of Bing. The readability of snippets in both engines mismatched with the reading comprehension of children in grades 6–8.

Research limitations/implications

The data corpus may be small. Analysis relied on quantitative measures.

Practical implications

Practitioners and other mediators should mitigate the readability issue in SERPs snippets. Researchers should consider text readability and word complexity simultaneously with other factors to obtain the nuanced understanding of young users’ web information behaviors. Additional theoretical and methodological implications are discussed.

Originality/value

This study measured the readability and the level of word complexity embedded in SERPs snippets and compared them to respective web pages in Google and Bing. Findings provide further evidence of the readability issue of SERPs snippets and the need to solve this issue through system design improvements.
Suitability of public-private-partnership procurement method for road projects in Sri Lanka
Authors: Dabarera G.K.M. , Perera B.A.K.S. , Rodrigo M.N.N.
Published: March 2019

Purpose

Governments of many developing countries that are unable to develop their infrastructure in order to obtain financial resources prefer to establish public–private partnerships (PPPs) for providing the much-required infrastructure. Time is thus opportune for Sri Lanka, which is also a developing country, to make use of PPPs to develop its road network. The purpose of this paper is, therefore, to identify the PPP models that suit road construction in Sri Lanka.

Design/methodology/approach

The study used a mixed approach. The characteristics of road construction, procurement selection factors to be considered in road construction, and the different PPP models that can be used for such procurements were identified through a comprehensive literature synthesis. The findings were validated using expert interviews. A questionnaire survey identified the PPP models that suit road construction in Sri Lanka. The most suitable model among them was identified by ranking the PPP models using procurement selection factors.

Findings

Build–Own–Operate–Transfer was identified as the PPP model that best suits road construction in Sri Lanka. However, investors may not find it attractive because of its high payback period, a result of the low traffic volume in Sri Lanka. Therefore, a PPP model that involves road construction alone will not be feasible in Sri Lanka. It will have to include the construction of other infrastructure as well.

Originality/value

The study identifies a PPP model that best suits the road construction projects in Sri Lanka.
Third-party underwriting and its effects on credit spreads and earnings management
Authors: Lyu Huaili , Yang Conghui
Published: March 2019

Purpose

The purpose of this paper is to examine the certification and monitoring motivations of third-party underwriting and its effects on credit spreads and earnings management of bank issuers.

Design/methodology/approach

Ordinary least squares is used to examine the certification and monitoring effects of third-party underwriting. Furthermore, the Heckman two-stage estimation method is used in controlling the endogeneity of sample selection.

Findings

The authors find that financial bonds underwritten by third-party underwriters bear lower credit spreads due to their credibly ex ante certification and effectively ex post monitoring compared with self-underwriting. Moreover, the certification of third-party underwriters can help to select good quality bond issuers with lower earnings management, and the monitoring function also plays an essential role in constraining the behavior of earnings management after the bond issues.

Research limitations/implications

The findings in this study suggest that underwriting types (third-party underwriting) will affect financial bond yields and bank issuers’ earnings management.

Practical implications

On the one hand, the authors should encourage third-party underwriters to actively promote the certification and monitoring functions. For example, given commercial banks the chance to be underwriters when the bond issuers are investment banks, which is not allowed now in China’s financial bond market. On the other hand, the authors should cut off the quid pro quo relations within third-party underwriting because such relations will reduce the certification and monitoring effects of third-party underwriters.

Originality/value

This is the first study to distinguish the certification and monitoring effects by using unique data from China’s financial bond market. And the authors further investigate the adverse effects of quid pro quo relations (hiring each other as lead underwriters) on the certification and monitoring effects of third-party underwriters.
An evidence-based urban DRR strategy for informal settlements
Authors: Sarmiento Juan Pablo , Polak Suzanne , Sandoval Vicente
Published: March 2019

Purpose

The purpose of this paper is to analyze the evidence-based research strategy (EBRS) used to evaluate eight projects that applied the neighborhood approach for disaster risk reduction (NA-DRR) in informal urban settlements in Colombia, Guatemala, Haiti, Honduras, Jamaica and Peru, between 2012 and 2017.

Design/methodology/approach

The study covers the first five of the seven EBRS stages: first, identify relevant interventions; second, prepare evaluation questions; third, select evidence sources and implement a search strategy; fourth, appraise evidences and identify gaps; fifth, create an evaluation design to include an extensive literature review, followed by a mixed research method with surveys, focus groups and interviews; disaster risk modeling; georeferencing analysis; and engineering inspections. The last two stages: sixth, apply the evidence, and seventh, evaluate the evidence application, will be addressed in a near future.

Findings

Even though the reference to “evidence” is frequent in the DRR field, it is largely based on descriptive processes, anecdotal references, best practices, lessons learned and case studies, and particularly deficient on the subject of informal and precariousness settlements. The evaluation allowed a deep and broad analysis of NA-DRR in urban informal settlements, comparing it with other DRR strategies implemented by different stakeholders in fragile urban settings, assessing the effectiveness and sustainability of the various DRR interventions.

Originality/value

The abundant data, information and knowledge generated will serve as foundation for forthcoming thematic peer-reviewed publications informing evidence-based DRR research, policy and practice, with emphasis on informal and precariousness settlements in particular.
Appraisal of fire safety interventions and strategies for informal settlements in South Africa
Authors: Walls Richard Shaun , Eksteen Rodney , Kahanji Charles , Cicione Antonio
Published: March 2019

Purpose

Informal settlements are inherently unstructured in nature, lack adequate services, regularly have high population densities and can experience social problems. Thus, fires can easily propagate rapidly through such areas, leaving thousands homeless in a single fire. The purpose of this paper is to present an appraisal of various interventions and strategies to improve fire safety in informal settlements in South Africa (globally, similar settlements are known as slums, ghettos, favelas, shantytowns, etc.), considering aspects of both technical suitability and social suitability.

Design/methodology/approach

This paper focusses on three specific aspects: ignition risk management, active fire protection interventions and passive fire protection interventions. These are presented within a framework to outline how they may mitigate the impact of fires.

Findings

Often “solutions” proposed to improve fire safety either lack a sound engineering basis, thus becoming technically inefficient, or do not consider social circumstances and community responses in settlements, thereby becoming practically, socially or economically unsuitable. It must be understood that there is no “quick fix” to this significant problem, but rather a combination of interventions can improve fire safety in general. A broad understanding of the various options available is essential when addressing this problem, which this paper seeks to provide.

Practical implications

This paper seeks to provide an overview to guide policymakers and organisations by illustrating both the advantages/benefits and disadvantages/challenges of the interventions and strategies currently being rolled out, as well as potential alternatives.

Originality/value

A broad but succinct appraisal is provided that gives insight and direction for improving fire safety in informal settlements. It is hoped that the challenges associated with the fire safety interventions discussed can be addressed and improved over time.
Digitalization, BIM ecosystem, and the future of built environment
Authors: Singh Vishal
Published: March 2019

Purpose

The purpose of this paper is to conduct a critical analysis of the commonly projected visions on the future of built environment, focusing on transformative research. The primary question is will the construction sector be able to make the projected transformative leap even if the history of technology adoption in construction suggests otherwise? And, what role can academic research play?

Design/methodology/approach

This paper is based on a reflective research and qualitative review of academic articles, white papers and reported projections for the future of construction. The reflections are based on discussions with colleagues and students, including thought experiments.

Findings

There is a general agreement across various sources about the key technical and social drivers for the future of construction. However, these projections seem to be emanating from industry insiders, and more diversity and creativity is needed in exploring alternative possibilities.

Research limitations/implications

The paper should be useful for researchers in assessing their research strategy, especially those aiming to focus on the future of construction and transformative research. The findings of this paper suggest the need for collaboration and explorations with diverse disciplines, including those that may not appear immediately connected to digital construction.

Practical implications

The paper should be useful for individuals and organizations, especially start-ups that are seeking novel opportunities to disrupt the future of construction.

Originality/value

The originality and value of this research lies in a timely critique of the commonly projected trends in the future of digital construction. The use of reflective research and thought experiments emphasizes the need for divergent thinking and creative research methods in construction research.
GreenGo’s new strategy in the carsharing market of Budapest
Authors: Bakonyi Zoltan , Gyurity Erik , Horvath Adam
Published: March 2019

Learning outcomes

The purpose of this paper is to demonstrate how a business idea can be successful in the long run in a rapidly changing environment. Students could learn about the carsharing market and the world of start-ups. During the lesson, students could practice business modelling based on “Value proposition Canvas”. With this model, they can understand the real needs of the customers and the services, with which companies can provide gains for the clients and decrease users’ pain. Beside business modelling, the case provides the opportunity to learn about the concept of First Mover Advantage, which describes the possible advantages of being first on a market. Three different sources can provide first mover advantage: technological leadership; pre-emption of scarce assets; and customer loyalty. Start-ups should systematically think about acquiring some of the above to sustain their advantage.

Case overview/synopsis

This case is about a carsharing start-up GreenGo, which was the first company introducing the concept of carsharing in Hungary. GreenGo was founded in November 2016 in Budapest. Until today, it has approximately 170 cars and could establish a solid customer base with 6,000 subscribers. After one year of monopoly, GreenGo got a competitor, when MOL (one of the largest companies of the Central European region) entered the market with its new carsharing service: MOL Limo (Limitless Mobility). MOL Limo is using the same business model and marketing mix as GreenGo and started to operate with 300 cars. The case describes the urban transportation of Budapest, the business model and value proposition of GreenGo and MOL Limo in depth. It also presents some possible options for GreenGo to react to the new market situation.

Complexity academic level

Master in management, MBA.

Supplementary materials

Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Subject code

CSS: Strategy, Case study organisation: GreenGo.
Work–life balance among working university students in Ghana
Authors: Tetteh Edward Nartey , Attiogbe Esther Julia Korkor
Published: March 2019

Purpose

The purpose of this paper is to explore how working university students in Ghana are able to combine work and study, and the effect of this on their academic performance.

Design/methodology/approach

An exploratory survey method is used to collect data from 360 working students randomly selected from four universities in Accra, Ghana. The study employs the Pearson product-moment correlation coefficient (r2) to test two hypotheses and both are affirmed by the results.

Findings

It is found that combining schooling with work results in less time for studies which negatively affects academic performance. Again, difficulty in finding time for studies due to work requirements ranks the highest, and finally, students receive slightly better support from their academic institutions than from their employers.

Research limitations/implications

The study focussed only on perspectives from working students in Ghana. The dimension of employers and officials of academic institutions was not investigated.

Practical implications

The findings imply that to achieve sustainable development in the tertiary education sector and even in industry, all stakeholders – universities, policymakers, employers, students, etc. – must find practical ways to assist these students to combine work and study.

Originality/value

The study bridges the empirical gap of this critical phenomenon in the Ghanaian context. It will inform government and corporate policy on higher-level skill development among the workforce, and also tertiary institutions on how to address the needs of the critical mass of working students.
Workplace mentoring of degree apprentices: developing principles for practice
Authors: Roberts Amanda , Storm Marion , Flynn Sarah
Published: March 2019

Purpose

The purpose of this paper is to focus on developing a deep understanding of the nature and impact of the workplace mentor role in degree apprenticeships (DAs). It investigates a theoretical model of DA workplace mentoring activity, with findings used to develop a set of principles for supporting the development of effective mentoring practice.

Design/methodology/approach

Data underpinning this paper were collected as part of the monitoring and evaluation of the first year of a Chartered Manager DA programme at a post-1992 university. Workplace mentors and mentees were interviewed to explore their experience of mentoring within this programme.

Findings

This study found there to be many positive benefits of workplace mentoring for apprentices, their mentors and the organisation. This understanding can be used to support the development of principles for effective mentoring practice.

Research limitations/implications

The data support the validity of the proposed model for DA workplace mentoring activity. In order to become a helpful guide to mentors’ planning of areas of support, the model may need to be refined to show the relative importance given to each activity area. The findings of this small-scale study need now to be extended through work with a larger sample.

Practical implications

The set of principles offered will be valuable to workplace mentors of degree apprentices across organisational sectors to ensure the quality of delivery and outcomes.

Originality/value

This paper contributes to an understanding of the impact of mentoring as a social practice on mentor and apprentice development. Such an understanding has the potential to positively influence the quality of delivery, mentoring practice and thus apprentices’ learning.