bluuebunny/crossref_metadata_2025 huggingface dataset:
Universal pathway for posttransfer editing reactions: Insights from the crystal structure of
Tt
PheRS with puromycin
Authors: Tworowski Dmitry , Klipcan Liron , Peretz Moshe , Moor Nina , Safro Mark G.
Published: March 2015

Significance

At the amino acid binding and recognition step, some aminoacyl-tRNA synthetases (aaRSs) face the challenge of discrimination between cognate and closely similar noncognate amino acids. To ensure a high fidelity of protein biosynthesis, aaRSs developed an additional editing activity associated with a specific site, where misacylated tRNAs are hydrolyzed. The structure of heterodimeric
Thermus thermophilus
phenylalanyl-tRNA synthetase (
Tt
PheRS) with the aminonucleoside antibiotic puromycin reveals the detailed architecture of the complex with ligand mimicking the A76 of tRNA misacylated with noncognate Tyr. Based on the crystal structure and using quantum mechanics/molecular mechanics approach, we present a universal hydrolytic mechanism utilizing cyclic 2′,3′-intermediates for
Tt
PheRS, and potentially for other class I and class II aaRSs.
ATM prevents DSB formation by coordinating SSB repair and cell cycle progression
Authors: Khoronenkova Svetlana V. , Dianov Grigory L.
Published: March 2015

Significance

DNA is chemically unstable; therefore, human cells have to repair a great number and variety of DNA lesions each day. DNA single-strand breaks (SSBs) represent one of the most dangerous lesions because, if unrepaired, they lead to genetic instability and are implicated in many human diseases. Here we report a novel mechanism that detects SSBs and controls the timing of SSB repair, thereby preventing the duplication of damaged DNA and the accumulation of mutations. Our findings shed important light on the molecular defects associated with the human disease ataxia-telangiectasia, which is caused by mutations in the
atm
gene.
RETRACTED: Atrial natriuretic peptide prevents cancer metastasis through vascular endothelial cells
Authors: Nojiri Takashi , Hosoda Hiroshi , Tokudome Takeshi , Miura Koichi , Ishikane Shin , Otani Kentaro , Kishimoto Ichiro , Shintani Yasushi , Inoue Masayoshi , Kimura Toru , Sawabata Noriyoshi , Minami Masato , Nakagiri Tomoyuki , Funaki Soichiro , Takeuchi Yukiyasu , Maeda Hajime , Kidoya Hiroyasu , Kiyonari Hiroshi , Shioi Go , Arai Yuji , Hasegawa Takeshi , Takakura Nobuyuki , Hori Megumi , Ohno Yuko , Miyazato Mikiya , Mochizuki Naoki , Okumura Meinoshin , Kangawa Kenji
Published: March 2015

Most patients suffering from cancer die of metastatic disease. Surgical removal of solid tumors is performed as an initial attempt to cure patients; however, surgery is often accompanied with trauma, which can promote early recurrence by provoking detachment of tumor cells into the blood stream or inducing systemic inflammation or both. We have previously reported that administration of atrial natriuretic peptide (ANP) during the perioperative period reduces inflammatory response and has a prophylactic effect on postoperative cardiopulmonary complications in lung cancer surgery. Here we demonstrate that cancer recurrence after curative surgery was significantly lower in ANP-treated patients than in control patients (surgery alone). ANP is known to bind specifically to NPR1 [also called guanylyl cyclase-A (GC-A) receptor]. In mouse models, we found that metastasis of GC-A–nonexpressing tumor cells (i.e., B16 mouse melanoma cells) to the lung was increased in vascular endothelium-specific
GC-A
knockout mice and decreased in vascular endothelium-specific
GC-A
transgenic mice compared with control mice. We examined the effect of ANP on tumor metastasis in mice treated with lipopolysaccharide, which mimics systemic inflammation induced by surgical stress. ANP inhibited the adhesion of cancer cells to pulmonary arterial and micro-vascular endothelial cells by suppressing the E-selectin expression that is promoted by inflammation. These results suggest that ANP prevents cancer metastasis by inhibiting the adhesion of tumor cells to inflamed endothelial cells.
Essential genome of
Pseudomonas aeruginosa
in cystic fibrosis sputum
Authors: Turner Keith H. , Wessel Aimee K. , Palmer Gregory C. , Murray Justine L. , Whiteley Marvin
Published: March 2015

Significance

The opportunistic pathogen
Pseudomonas aeruginosa
thrives in cystic fibrosis (CF) lung sputum. Here, we define the essential genome of two
P. aeruginosa
strains in laboratory media and in CF sputum. We also use genomic methods to profile
P. aeruginosa
genetic requirements for fitness in both natural and synthetic CF sputum. Finally, we show that the essential genomes of different strains of
P. aeruginosa
are distinct, suggesting that the architecture of genetic networks is a primary determinant of a gene’s role in fitness. This has implications for the development of strain-independent therapeutics and underscores the importance of functional studies in pathogenic strains of interest.
Coselected genes determine adaptive variation in herbivore resistance throughout the native range of
Arabidopsis thaliana
Authors: Brachi Benjamin , Meyer Christopher G. , Villoutreix Romain , Platt Alexander , Morton Timothy C. , Roux Fabrice , Bergelson Joy
Published: March 2015

Significance

How organisms adapt to the biotic and abiotic environment is a major question in evolutionary biology that addresses how natural selection shapes biodiversity. Using mass spectrometry, we characterized natural variation in major defense molecules, aliphatic glucosinolates, in hundreds of ecotypes of the model plant
Arabidopsis thaliana
, spanning the native range of the species. Using extensive genomic resources and field experiments, we provide strong evidence that populations are adapted to local herbivore communities along a striking longitudinal cline. In addition, we show that only a few genes of strong effect govern this natural variation and that alleles at these genes, located on different chromosomes, appear to have coevolved through epistatic selection.
Two transcription factors, Pou4f2 and Isl1, are sufficient to specify the retinal ganglion cell fate
Authors: Wu Fuguo , Kaczynski Tadeusz J. , Sethuramanujam Santhosh , Li Renzhong , Jain Varsha , Slaughter Malcolm , Mu Xiuqian
Published: March 2015

Significance

Despite the progress made during the last two decades regarding the generation of retinal cell types, the mechanisms by which a retinal progenitor cell decides to adopt a particular cell type remain unclear. Using a binary knockin-transgenic system, we show that two factors, POU domain, class 4, transcription factor 2 (Pou4f2) and insulin gene enhancer protein 1 (Isl1), specify the retinal ganglion cell (RGC) fate and activate the whole gene-expression program required for ganglion cell differentiation. This study, for the first time to our knowledge, defines a set of determinant factors for any retinal cell type, offering significant insight into how cellular diversity is achieved in the central nervous system. It also provides guidance for generating RGCs in vitro for therapeutic purposes.
Adult hippocampal neural stem and progenitor cells regulate the neurogenic niche by secreting VEGF
Authors: Kirby Elizabeth D. , Kuwahara Akela A. , Messer Reanna L. , Wyss-Coray Tony
Published: March 2015

Significance

Adult hippocampal neurogenesis is a lifelong process by which new neurons are derived from a pool of resident stem and progenitor cells. Research on the functional role of this process has, to date, focused on the contributions of new, highly plastic neurons to memory function. We show here a previously unidentified functional role of undifferentiated neural stem and progenitor cells in the adult hippocampus as secretory cells that help maintain their own neurogenic niche by secreting large, biologically relevant quantities of the essential growth factor, VEGF. These findings suggest that the function of adult neurogenesis may include the secretome of undifferentiated stem and progenitor cells.
New aspect of plant–rhizobia interaction: Alkaloid biosynthesis in
Crotalaria
depends on nodulation
Authors: Irmer Simon , Podzun Nora , Langel Dorothee , Heidemann Franziska , Kaltenegger Elisabeth , Schemmerling Brigitte , Geilfus Christoph-Martin , Zörb Christian , Ober Dietrich
Published: March 2015

Significance

Nodules are typical organs at the roots of legumes (Fabaceae) in which symbiotic rhizobia fix atmospheric nitrogen. The fabaceous genus
Crotalaria
is known to produce toxic alkaloids as part of its chemical defense. We show that, in
Crotalaria
, nodulation triggers the biosynthesis of these alkaloids. The first specific enzyme of their biosynthesis is of plant origin and is expressed exclusively in the nodules.
Molecular ruler determines needle length for the
Salmonella
Spi-1 injectisome
Authors: Wee Daniel H. , Hughes Kelly T.
Published: March 2015

Significance

Type-III secretion systems facilitate the virulence capability of Gram-negative bacterial pathogens. They are part of complex nanomachines that include the bacterial flagellum, which confers motility, and the injectisome, which secretes proteins from the infecting bacterial cytoplasm into eukaryotic host cells. Here we examine the mechanisms of length control for the main component of the injectisome and flagellar basal structures, the needle and the hook, respectively. The defined lengths of the hook and needle are important for their function. We find that both systems use a secreted, molecular ruler to effect length determination at the nanometer-scale. Understanding the mechanisms of length control in these systems provides insight into bacterial pathogens and a biological model for the controlled construction of nanomaterials.
Herpes simplex viral-vector design for efficient transduction of nonneuronal cells without cytotoxicity
Authors: Miyagawa Yoshitaka , Marino Pietro , Verlengia Gianluca , Uchida Hiroaki , Goins William F. , Yokota Shinichiro , Geller David A. , Yoshida Osamu , Mester Joseph , Cohen Justus B. , Glorioso Joseph C.
Published: March 2015

Significance

Gene therapy has made significant strides in the treatment and even cure of single-gene defects. However, the maturation of this field will require more sophisticated vehicles capable of cell-selective delivery of large genetic payloads whose regulated expression will restore or enhance cellular functionality. High-capacity herpes simplex virus vectors have the potential to meet these challenges but have been limited by the need to preserve one particularly cytotoxic viral product, infected cell polypeptide 0, to maintain transgene transcriptional activity. Our study describes a vector design that solves this conundrum, thereby promising the near-term availability of viral vectors that can efficiently deliver large or multiple regulated transgenes to a diversity of cells without attendant cytotoxicity.
Vernalizing cold is registered digitally at
FLC
Authors: Angel Andrew , Song Jie , Yang Hongchun , Questa Julia I. , Dean Caroline , Howard Martin
Published: March 2015

Significance

How organisms monitor external environmental signals and integrate these measurements into their development is a fundamental question. Here, we investigate this issue in the context of vernalization, the perception and memory of long-term cold temperature exposure in plants. We use a combination of mathematical modeling coupled with experiments on plants exposed to an interrupted cold temperature regime. We find that cold temperature exposure is likely to be registered in an all-or-nothing (digital) manner at the relevant gene
FLOWERING LOCUS C
. Such a mechanism allows for integration of noisy, interrupted temperature signals and for subsequent switching into a stable, digital epigenetic memory state. This analysis is a key step toward uncovering the biochemical elements behind long-term cold temperature monitoring.
Microdroplet fusion mass spectrometry for fast reaction kinetics
Authors: Lee Jae Kyoo , Kim Samuel , Nam Hong Gil , Zare Richard N.
Published: March 2015

Significance

Time-resolved mass spectrometry is a powerful approach for identifying reaction intermediates and measuring reaction kinetics, yet one critical limitation is temporal resolution. Here, we describe microdroplet fusion mass spectrometry on timescales as short as microseconds. In our approach, two high-speed streams of liquid microdroplets collide to make fused droplets of 13 ± 6 μm in diameter, where the reactants are mixed in a negligible time. After a short flying time of 50 μs or less during which the reaction proceeds, the fused droplets enter a mass spectrometer for chemical analysis of intermediates and reaction products. This enables observation of early events of various fast chemical reactions in the liquid phase.
The “national key” in Bosnia and Herzegovina: a historical perspective†
Authors: Pearson Sevan
Published: March 2015

The 1995 Dayton Peace Agreement in Bosnia and Herzegovina instituted ethnic quotas between Bosniaks, Serbs, and Croats: the three “constituent peoples.” This institutionalization of ethnicity, criticized by some contemporary authors, is often seen as a creation of the peace agreement. Interestingly, several scholars deem such proportional representation a legacy from socialist times. But the existing literature lacks a historical perspective on the question of ethnic quotas. In addressing this issue, this paper reminds one of the existence of ethnic quotas, called the “national key,” during socialist times. A deeper analysis of the “national key” in the Socialist Republic of Bosnia and Herzegovina and of the ethnic quotas in the last two decades shows, interestingly, more differences than continuity. The article concludes that few similarities and more differences can be observed between the two periods, especially regarding the legal aspects of the “national key,” in ideological justification and in the conceptions based on parity or proportional representation.
Reasons for EU double standards: comparative overview of the cases of the Erased and the Non-citizens
Authors: Vrbek Sanja
Published: March 2015

On the basis of a comparative analysis of the case studies of the Slovenian Erased and the Latvian Non-citizens, the paper endeavors to identify the reasons for the EU involvement in the latter, but not the former case. These two situations are recognized as similar enough to be compared, and endure the counter-argumentation that the different EU approach is conditioned by the specifics of the local context, not by double standards. Hence, the paper comes to a conclusion that the involvement in Latvia has been conditioned by the fear of the potentially violent conflict, the existence of a proactive kin state, and a minority, significant in number, as well as the explicitly discriminatory legal framework that was in collision with the EU economicacquis.Thus, it has been inferred that double standards occur due to the lack of EU and international interest in these situations of human rights violations, where the powerful kin state and the minority, significant in number, are absent, do not have a potential to develop into a violent conflict, do not derive from explicitly discriminatory legal provision, and do not challenge the fundamental market freedoms of the EU.
The taste system of small fish species
Authors: Okada Shinji
Published: March 2015

Small fish species such as the zebrafish (Danio rerio) and medaka fish (Oryzias latipes) are advantageous animal models and have been used as model organisms in many research areas. However, they have not been utilized for studying the taste system, primarily because of a dearth of molecular biological knowledge. Quantitative methods for analyzing the taste preferences of fish species have also been lacking. Recent progress of the fish genome project has enabled the elucidation of the molecular mechanisms of taste sensation. Taste receptors and a number of signal transduction molecules have been identified. Additionally, the development of quantitative methods of feeding using fluorescently labeled artificial foods has demonstrated taste preferences in small fish species. Comparisons between these results in fish and reports on mammals have proposed a general logic and evolution of vertebrate taste systems. Analysis on the transsynaptic tracer-expressing transgenic medaka fish also suggests the usefulness of small fish in the research of neural circuits for taste.
IgE-activated basophils regulate eosinophil tissue entry by modulating endothelial function
Authors: Cheng Laurence E. , Sullivan Brandon M. , Retana Lizett E. , Allen Christopher D.C. , Liang Hong-Erh , Locksley Richard M.
Published: March 2015

Vertebrate immunity has evolved a modular architecture in response to perturbations. Allergic inflammation represents such a module, with signature features of antigen-specific IgE and tissue eosinophilia, although the cellular and molecular circuitry coupling these responses remains unclear. Here, we use genetic and imaging approaches in models of IgE-dependent eosinophilic dermatitis to demonstrate a requisite role for basophils. After antigenic inflammation, basophils initiate transmigration like other granulocytes but, upon activation via their high-affinity IgE receptor, alter their migratory kinetics to persist at the endothelium. Prolonged basophil–endothelial interactions, in part dependent on activation of focal adhesion kinases, promote delivery of basophil-derived IL-4 to the endothelium and subsequent induction of endothelial vascular cell adhesion molecule-1 (VCAM-1), which is required for eosinophil accumulation. Thus, basophils are gatekeepers that link adaptive immunity with innate effector programs by altering access to tissue sites by activation-induced interactions with the endothelium.
Apparent lack of physical or functional interaction between CaV1.1 and its distal C terminus
Authors: Ohrtman Joshua D. , Romberg Christin F. , Moua Ong , Bannister Roger A. , Levinson S. Rock , Beam Kurt G.
Published: March 2015

CaV1.1 acts as both the voltage sensor that triggers excitation–contraction coupling in skeletal muscle and as an L-type Ca2+ channel. It has been proposed that, after its posttranslational cleavage, the distal C terminus of CaV1.1 remains noncovalently associated with proximal CaV1.1, and that tethering of protein kinase A to the distal C terminus is required for depolarization-induced potentiation of L-type Ca2+ current in skeletal muscle. Here, we report that association of the distal C terminus with proximal CaV1.1 cannot be detected by either immunoprecipitation of mouse skeletal muscle or by colocalized fluorescence after expression in adult skeletal muscle fibers of a CaV1.1 construct labeled with yellow fluorescent protein (YFP) and cyan fluorescent protein on the N and C termini, respectively. We found that L-type Ca2+ channel activity was similar after expression of constructs that either did (YFP-CaV1.11860) or did not (YFP-CaV1.11666) contain coding sequence for the distal C-terminal domain in dysgenic myotubes null for endogenous CaV1.1. Furthermore, in response to strong (up to 90 mV) or long-lasting prepulses (up to 200 ms), tail current amplitudes and decay times were equally increased in dysgenic myotubes expressing either YFP-CaV1.11860 or YFP-CaV1.11666, suggesting that the distal C-terminal domain was not required for depolarization-induced potentiation. Thus, our experiments do not support the existence of either biochemical or functional interactions between proximal CaV1.1 and the distal C terminus.
The number of limit cycles of the FitzHugh nerve system
Authors: Chen Hebai , Xie Jianhua
Published: March 2015

In this paper we give a complete analysis of the number of limit cycles of the FitzHugh nerve system. First, we prove the uniqueness of the limit cycle when the unique equilibrium is a source. We then show that the system has two limit cycles if the unique equilibrium is a sink and limit cycles exist. We will also show that the mathematical study of limit cycles for FitzHugh nerve systems is related to Hilbert’s 16

th

^{\mbox {th}}

problem and is therefore an important area of study.
Cardinal: an R package for statistical analysis of mass spectrometry-based imaging experiments
Authors: Bemis Kyle D. , Harry April , Eberlin Livia S. , Ferreira Christina , van de Ven Stephanie M. , Mallick Parag , Stolowitz Mark , Vitek Olga
Published: March 2015

Cardinal is an R package for statistical analysis of mass spectrometry-based imaging (MSI) experiments of biological samples such as tissues. Cardinal supports both Matrix-Assisted Laser Desorption/Ionization (MALDI) and Desorption Electrospray Ionization-based MSI workflows, and experiments with multiple tissues and complex designs. The main analytical functionalities include (1) image segmentation, which partitions a tissue into regions of homogeneous chemical composition, selects the number of segments and the subset of informative ions, and characterizes the associated uncertainty and (2) image classification, which assigns locations on the tissue to pre-defined classes, selects the subset of informative ions, and estimates the resulting classification error by (cross-) validation. The statistical methods are based on mixture modeling and regularization.

Contact: o.vitek@neu.edu

Availability and implementation: The code, the documentation, and examples are available open-source at www.cardinalmsi.org under the Artistic-2.0 license. The package is available at www.bioconductor.org.
Casitas: a location-dependent ecological trap for juvenile Caribbean spiny lobsters, Panulirus argus
Authors: Gutzler Benjamin C. , Butler Mark J. , Behringer Donald C.
Published: March 2015

Casitas are artificial shelters used by fishers to aggregate Caribbean spiny lobsters (Panulirus argus) for ease of capture. However, casitas may function as an ecological trap for juvenile lobsters if they are attracted to casitas and their growth or mortality is poorer compared with natural shelters. We hypothesized that juvenile lobsters may be at particular risk if attracted to casitas because they are less able than larger individuals to defend themselves, and do not forage far from shelter. We compared the nutritional condition, relative mortality, and activity of lobsters of various sizes in casitas and natural shelters in adult and juvenile lobster-dominated habitats in the Florida Keys (United States). We found that the ecological effects of casitas are complex and location-dependent. Lobsters collected from casitas and natural shelters did not differ in nutritional condition. However, juvenile lobsters in casitas experienced higher rates of mortality than did individuals in natural shelters; the mortality of large lobsters did not differ between casitas and natural shelters. Thus, casitas only function as ecological traps when deployed in nursery habitats where juvenile lobsters are lured by conspecifics to casitas where their risk of predation is higher. These results highlight the importance of accounting for animal size and location-dependent effects when considering the consequences of habitat modification for fisheries enhancement.
mRNA maturation in giant viruses: variation on a theme
Authors: Priet Stéphane , Lartigue Audrey , Debart Françoise , Claverie Jean-Michel , Abergel Chantal
Published: March 2015

Giant viruses from the Mimiviridae family replicate entirely in their host cytoplasm where their genes are transcribed by a viral transcription apparatus. mRNA polyadenylation uniquely occurs at hairpin-forming palindromic sequences terminating viral transcripts. Here we show that a conserved gene cluster both encode the enzyme responsible for the hairpin cleavage and the viral polyA polymerases (vPAP). Unexpectedly, the vPAPs are homodimeric and uniquely self-processive. The vPAP backbone structures exhibit a symmetrical architecture with two subdomains sharing a nucleotidyltransferase topology, suggesting that vPAPs originate from an ancestral duplication. A Poxvirus processivity factor homologue encoded by Megavirus chilensis displays a conserved 5′-GpppA 2′O methyltransferase activity but is also able to internally methylate the mRNAs’ polyA tails. These findings elucidate how the arm wrestling between hosts and their viruses to access the translation machinery is taking place in Mimiviridae.
Melatonin: a possible link between the presence of artificial light at night and reductions in biological fitness
Authors: Jones Therésa M. , Durrant Joanna , Michaelides Ellie B. , Green Mark P.
Published: March 2015

The mechanisms underpinning the ecological impacts of the presence of artificial night lighting remain elusive. One suspected underlying cause is that the presence of light at night (LAN) supresses nocturnal production of melatonin, a key driver of biological rhythm and a potent antioxidant with a proposed role in immune function. Here, we briefly review the evidence for melatonin as the link between LAN and changes in behaviour and physiology. We then present preliminary data supporting the potential for melatonin to act as a recovery agent mitigating the negative effects of LAN in an invertebrate. Adult crickets (Teleogryllus commodus), exposed to constant illumination, were provided with dietary melatonin (concentrations: 0, 10 or 100 µg ml−1) in their drinking water. We then compared survival, lifetime fecundity and, over a 4-week period, immune function (haemocyte concentration, lysozyme-like and phenoloxidase (PO) activity). Melatonin supplementation was able only partially to mitigate the detrimental effects of LAN: it did not improve survival or fecundity or PO activity, but it had a largely dose-dependent positive effect on haemocyte concentration and lysozyme-like activity. We discuss the implications of these relationships, as well as the usefulness of invertebrates as model species for future studies that explore the effects of LAN.
Light pollution alters the phenology of dawn and dusk singing in common European songbirds
Authors: Da Silva Arnaud , Valcu Mihai , Kempenaers Bart
Published: March 2015

Artificial night lighting is expanding globally, but its ecological consequences remain little understood. Animals often use changes in day length as a cue to time seasonal behaviour. Artificial night lighting may influence the perception of day length, and may thus affect both circadian and circannual rhythms. Over a 3.5 month period, from winter to breeding, we recorded daily singing activity of six common songbird species in 12 woodland sites, half of which were affected by street lighting. We previously reported on analyses suggesting that artificial night lighting affects the daily timing of singing in five species. The main aim of this study was to investigate whether the presence of artificial night lighting is also associated with the seasonal occurrence of dawn and dusk singing. We found that in four species dawn and dusk singing developed earlier in the year at sites exposed to light pollution. We also examined the effects of weather conditions and found that rain and low temperatures negatively affected the occurrence of dawn and dusk singing. Our results support the hypothesis that artificial night lighting alters natural seasonal rhythms, independently of other effects of urbanization. The fitness consequences of the observed changes in seasonal timing of behaviour remain unknown.
The impacts of new street light technologies: experimentally testing the effects on bats of changing from low-pressure sodium to white metal halide
Authors: Stone Emma Louise , Wakefield Andrew , Harris Stephen , Jones Gareth
Published: March 2015

Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species
Pipistrellus pipistrellus
,
P. pygmaeus
and
Nyctalus/Eptesicus
spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale.
A nucleosome turnover map reveals that the stability of histone H4 Lys20 methylation depends on histone recycling in transcribed chromatin
Authors: Svensson J. Peter , Shukla Manu , Menendez-Benito Victoria , Norman-Axelsson Ulrika , Audergon Pauline , Sinha Indranil , Tanny Jason C. , Allshire Robin C. , Ekwall Karl
Published: March 2015

Nucleosome composition actively contributes to chromatin structure and accessibility. Cells have developed mechanisms to remove or recycle histones, generating a landscape of differentially aged nucleosomes. This study aimed to create a high-resolution, genome-wide map of nucleosome turnover in Schizosaccharomyces pombe. The recombination-induced tag exchange (RITE) method was used to study replication-independent nucleosome turnover through the appearance of new histone H3 and the disappearance or preservation of old histone H3. The genome-wide location of histones was determined by chromatin immunoprecipitation–exonuclease methodology (ChIP-exo). The findings were compared with diverse chromatin marks, including histone variant H2A.Z, post-translational histone modifications, and Pol II binding. Finally, genome-wide mapping of the methylation states of H4K20 was performed to determine the relationship between methylation (mono, di, and tri) of this residue and nucleosome turnover. Our analysis showed that histone recycling resulted in low nucleosome turnover in the coding regions of active genes, stably expressed at intermediate levels. High levels of transcription resulted in the incorporation of new histones primarily at the end of transcribed units. H4K20 was methylated in low-turnover nucleosomes in euchromatic regions, notably in the coding regions of long genes that were expressed at low levels. This transcription-dependent accumulation of histone methylation was dependent on the histone chaperone complex FACT. Our data showed that nucleosome turnover is highly dynamic in the genome and that several mechanisms are at play to either maintain or suppress stability. In particular, we found that FACT-associated transcription conserves histones by recycling them and is required for progressive H4K20 methylation.
Impact of adolescent sucrose access on cognitive control, recognition memory, and parvalbumin immunoreactivity
Authors: Reichelt Amy C , Killcross Simon , Hambly Luke D. , Morris Margaret J. , Westbrook R. Fred
Published: March 2015

In this study we sought to determine the effect of daily sucrose consumption in young rats on their subsequent performance in tasks that involve the prefrontal cortex and hippocampus. High levels of sugar consumption have been associated with the development of obesity, however less is known about how sugar consumption influences behavioral control and high-order cognitive processes. Of particular concern is the fact that sugar intake is greatest in adolescence, an important neurodevelopmental period. We provided sucrose to rats when they were progressing through puberty and adolescence. Cognitive performance was assessed in adulthood on a task related to executive function, a rodent analog of the Stroop task. We found that sucrose-exposed rats failed to show context-appropriate responding during incongruent stimulus compounds presented at test, indicative of impairments in prefrontal cortex function. Sucrose exposed rats also showed deficits in an on object-in-place recognition memory task, indicating that both prefrontal and hippocampal function was impaired. Analysis of brains showed a reduction in expression of parvalbumin-immunoreactive GABAergic interneurons in the hippocampus and prefrontal cortex, indicating that sucrose consumption during adolescence induced long-term pathology, potentially underpinning the cognitive deficits observed. These results suggest that consumption of high levels of sugar-sweetened beverages by adolescents may also impair neurocognitive functions affecting decision-making and memory, potentially rendering them at risk for developing mental health disorders.
A square-planar hydrated cationic tetrakis(methimazole)gold(III) complex
Authors: Lynch Will E. , Padgett Clifford W. , Quillian Brandon , Haddock John
Published: March 2015

The cationic pseudo-square-planar complex tetrakis(1-methyl-2,3-dihydro-1H-imidazole-2-thione-κS)gold(III) trichloride sesquihydrate, [Au(C4H6N2S)4]Cl3·1.5H2O, was isolated as dark-red crystals from the reaction of chloroauric acid trihydrate (HAuCl4·3H2O) with four equivalents of methimazole in methanol. The AuIIIatoms reside at the corners of the unit cell on an inversion center and are bound by the S atoms of four methimazole ligands in a planar arrangement, with S—Au—S bond angles of approximately 90°.
A monoclinic form of dendocarbin A: a borderline case of one-dimensional isostructural polymorphism
Authors: Paz Cristian , Burgos Viviana , Suarez Sebastián , Baggio Ricardo
Published: March 2015

The title compound, dendocarbin A [systematic name: (1R,5aS,9aS,9bR)-1-hydroxy-6,6,9a-trimethyldodecahydronaphtho[1,2-c]furan-3-one], C15H22O3, is a sesquiterpene lactone isolated fromDrimys winterivarchilensis. The monoclinic phase described herein displays an identical molecular structure to the orthorhombic phase that we reported previously [Paz Robleset al.(2014).Acta Cryst.C70, 1007–1010], while varying significantly in chain pitch, and can thus be considered as a borderline case of one-dimensional isostructural polymorphism.
Crystal structure of (2E)-2-methoxyimino-2-{2-[(2-methylphenoxy)methyl]phenyl}-N′-(4-nitrobenzylidene)ethanohydrazide
Authors: Shripanavar Chetan Shrimandhar , Butcher Ray J.
Published: March 2015

The title compound, C24H22N4O5, crystallizes with two molecules in the asymmetric unit (Z′ = 2) oriented almost perpendicular to each other [dihedral angle between the central core of each molecule = 77.95 (3)°]. The two molecules exhibit similar conformations with an extended structure. An intramolecular C—H...N hydrogen bond occurs in each molecule. The two molecules are linked by a bifurcated N—H...(O,N) hydrogen bond involving the NH group in moleculeAas donor. They are further linked into a ribbon along thea-axis direction by further bifurcated N—H...(O,N) hydrogen bonds involving the NH group in moleculeBas donor. C—H...O interactions are also observed.
Food advertising as a mirror of intercultural differences: the case of the UK and Greece
Authors: Theocharous Andriani
Published: March 2015

Purpose

– The purpose of this paper is to identify cultural preferences in advertising style in the UK and Greece through the comparison of advertisements for food products of local brands.

Design/methodology/approach

– In total, 39 advertisements were collected from local food magazines in 2012-2013. Each copy was content-analyzed based on three dimensions of advertising style: advertising forms, appeals, and verbal communication style.

Findings

– The analysis of the copies shows a tendency for Greek advertisements to adopt a forceful style and to convey an abundance of factual information in direct forms, combined with emotional appeals emphasizing local origin, nostalgia, and long-standing cultural traditions. On the contrary, UK copies tend to emphasize the entertainment value of advertisements, while communicating rational appeals in an informal register.

Research limitations/implications

– The variations in advertising style for the promotion of food products in the UK and Greece reflect the different ways in which advertising works, and potential differences in consumers’ decision making when it comes to the purchase of the products. The findings could have relevance for the design and transcreation of multinational food campaigns, and they could facilitate the development of research questions to be addressed in food marketing and advertising and consumer behaviour research.

Originality/value

– The study adopts an interdisciplinary approach to the analysis of the copies and the interpretation of findings, which draws on marketing and advertising and integrates a linguistic analysis of the text. By focusing on a particular product category and origin, it attempts to comprehensively account for their effect on advertising practices.
Nutrition information and its influence on menu choice within higher education establishments
Authors: Feldman Charles H. , Hartwell Heather , Brusca Joseph , Su Haiyan , Zhao Hang
Published: March 2015

Purpose

– The purpose of this paper is to evaluate the influence of nutritional information on menu choices in a higher educational setting using a menu designed by the students themselves.

Design/methodology/approach

– Based on USDA healthy eating standards, a menu comprising seven healthy and seven unhealthy meal options were presented, once unlabeled as control (n=214) and once labeled with healthy and non-healthy nutrient icons as an intervention test menu (n=212).

Findings

– Findings demonstrate that despite a positive observed trend, there were no significant differences between healthy selection of labeled and unlabeled dishes (p=0.16).

Practical implications

– Providing nutritional information in student cafeterias may be challenging but helpful. However, more strategies need to be developed with student input to provide nutrition data on menus in an informative, comprehensive, yet friendly way that encourages healthy eating in campus foodservices.

Social implications

– No labeling system or legislation can control choices made by individuals, so the responsibility for a healthy selection must always remain personal. However, consumers should have input on menus as they have a stake in the outcome of the products.

Originality/value

– This novel study tested a student-designed menu to assess whether user input can influence food choice.
How to optimize the cost and time of the acquisitions process?
Authors: Kont Kate-Riin
Published: March 2015

Purpose

– The purpose of this paper is to focus on the history and new developments of the optimization and analysis of acquisitions costs. More specifically, the acquisition cost and time optimization methods studied concern primarily print format books. Though e-books have begun to be developed more and more, the print format books – both scientific books and textbooks – are still very important for university libraries and continue to pour into acquisition activities.

Design/methodology/approach

– The data used in this paper are based on a review of relevant literature to provide an overview of the different concepts of the budget allocation and cost accounting methods suitable for the optimizing cost and time of the acquisition process. Different methods are described via reviewing example studies.

Findings

– On the basis of the current study, it can be said that the acquisitions procedure is more labor-intensive than any other library procedure both historically and nowadays. Nonetheless, the routines of acquisitions have been fairly well fixed over the years and constantly have searched for new ways to reduce costs. The most popular methods to control the acquisitions budget have been centralized and cooperative acquisitions, using vendors for acquiring library materials, customer-based acquisitions, and price indexes. New costing methods described, like activity-based costing and time-driven activity-based costing methodologies seem both to be the best tools for understanding acquisitions cost behavior and for refining a cost system for university libraries.

Originality/value

– This paper raises a perspective in library acquisitions management that has not been dealt with before. Namely, it explores how the library materials selection moved from intrinsic wisdom of bookish librarians and “just in case” inventory model to “purchase by customer suggestion” model. In addition, how libraries moved from acting on the basis of guesses to examine the cost breakdown of the acquisitions-related activities in a library.
The internet as a data source for advancement in social sciences
Authors: Askitas Nikolaos , Zimmermann Klaus F.
Published: March 2015

Purpose

– The purpose of this paper is to recommend the use of internet data for social sciences with a special focus on human resources issues. It discusses the potentials and challenges of internet data for social sciences. The authors present a selection of the relevant literature to establish the wide spectrum of topics, which can be reached with this type of data, and link them to the papers in thisInternational Journal of Manpowerspecial issue.

Design/methodology/approach

– Internet data are increasingly representing a large part of everyday life, which cannot be measured otherwise. The information is timely, perhaps even daily following the factual process. It typically involves large numbers of observations and allows for flexible conceptual forms and experimental settings.

Findings

– Internet data can successfully be applied to a very wide range of human resource issues including forecasting (e.g. of unemployment, consumption goods, tourism, festival winners and the like), nowcasting (obtaining relevant information much earlier than through traditional data collection techniques), detecting health issues and well-being (e.g. flu, malaise and ill-being during economic crises), documenting the matching process in various parts of individual life (e.g. jobs, partnership, shopping), and measuring complex processes where traditional data have known deficits (e.g. international migration, collective bargaining agreements in developing countries). Major problems in data analysis are still unsolved and more research on data reliability is needed.

Research limitations/implications

– The data in the reviewed literature are unexplored and underused and the methods available are confronted with known and new challenges. Current research is highly original but also exploratory and premature.

Originality/value

– The paper reviews the current attempts in the literature to incorporate internet data into the mainstream of scholarly empirical research and guides the reader through this Special Issue. The authors provide some insights and a brief overview of the current state of research.
Consumer software piracy in virtual communities
Authors: Yu Chia-ping , Young Mei-Lien , Ju Bao-Chang
Published: March 2015

Purpose

– In consumer marketing literature, the ethical/moral components of consumer behavior have been recognized as important factors in individuals’ involvement in software piracy. However, there remains unanswered the question of which specific components are being referred to and how they explain consumer software piracy in the virtual knowledge-sharing community. This question is particularly unaddressed for those consumers who take the risks associated with piracy believing their acts to be taking from the haves (software producers) and giving to the have-nots. The paper aims to discuss this issue.

Design/methodology/approach

– In this research, the authors propose a synergistic model that adopts the perspective of heroism and social exchange, and test it with the data collected from a virtual community. To test the proposed research model, the authors investigated 489 subjects and examined the hypotheses by applying the partial least squares method.

Findings

– The findings show that the heroism construct has significant influence on sharing behavior in relation to cost factors, but not to benefit factors. Heroism stands out as the major construct in explaining sharing behavior. Thus, the research shows that the consumer software piracy present in the virtual knowledge-sharing community is a social behavior of exchange.

Originality/value

– Methodologically, the study proposes a new model for researchers and practitioners to understand consumer software piracy in the virtual community. Managerially, software producers should take it into consideration when formulating their product-pricing strategy, to ensure that software producers and the young can both win in the “buy or steal” war.
Self-disclosure in social networking sites
Authors: Cheung Christy , Lee Zach  W. Y. , Chan Tommy  K. H.
Published: March 2015

Purpose

– The purpose of this paper is to examine the relative impacts of perceived cost, perceived benefits, and social influence on self-disclosure behaviors in social networking sites under an integrated theoretical framework.

Design/methodology/approach

– Building upon social exchange theory and privacy calculus theory, an integrated model was developed. The model was tested empirically using a sample of 405 social networking site’s users. Users were required to complete a survey regarding self-disclosure behaviors in Facebook.

Findings

– The results indicate that social influence is the factor which exhibits the strongest effect on self-disclosure in social networking sites, followed by perceived benefits. Surprisingly, perceived privacy risk does not have any significant impact on self-disclosure.

Research limitations/implications

– The results inform researchers about the importance to incorporate social influence factors and cultural factors into future online self-disclosure study.

Practical implications

– The results suggest that users focus on the benefits as well as social influence when they decide to reveal personal information in social networking sites, but pay less attention to the potential privacy risks. Educators are advised to launch educational programs to raise students’ awareness to the potential risks of self-disclosure in social networking sites. Service providers of social networking sites are encouraged to provide intuitive privacy indices showing users the levels of privacy protection.

Originality/value

– This paper is one of the first to develop and empirically tests an integrated model of self-disclosure in social networking sites.
A strategy-based model for implementing channel integration in e-commerce
Authors: Wu Ing-Long , Wu Shwu-Ming
Published: March 2015

Purpose

– The key to success in the internet business lies in how you carry out the integration between virtual and physical channels. The purpose of this paper is to aim at defining the solution to the integration.

Design/methodology/approach

– Channel coordination is grounded on a new governance of integration strategy which bridges the channels. This study proposes a novel research model with three stages: first, click-and-brick strategies; second, channel coordination for three purchase stages; and third, synergy realizations. A survey was conducted for collecting empirical data. PLS was used for path analysis. In total, three separate statistical analyses were performed for three defined integration strategies.

Findings

– Click-and-brick strategies have different degrees of impact on channel coordination in different purchase stages and in turn, different degrees of impact on synergy benefits. Specifically, the in-house division strategy is more important in determining channel coordination in the three purchase stages.

Practical implications

– Customers initially perceive online services with a nature of low trust and view them as highly risky. This integration is useful for a firm to successfully start a new online business. Further, it provides insight into allocating a firm’s resources to critical multi-channel activities to realize synergy benefits.

Originality/value

– Multi-channel marketing is dynamic and complex in nature. Existing theories provide limited insight into effectively defining them. This study attempted to define a strategy-based implementation model. This model demonstrated the capability to effectively reduce the complexity of defining channel integration.