bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcriptome Profiling of Bigelowiella natans in Response to Light Stress
Authors: Rangsrikitphoti Pattarasiri , Durnford Dion G. 
Published: July 2018

AbstractBigelowiella natans is a marine chlorarachniophyte whose plastid was acquired secondarily via endosymbiosis with a green alga. During plastid evolution, the photosynthetic endosymbiont would have integrated with the host metabolic pathways. This would require the evolution and coordination of strategies to cope with changes in light intensity that includes changes in the expression of both endosymbiont and host‐derived genes. To investigate the transcriptional response to light intensity in chlorarachniophytes, we conducted an RNA‐seq experiment to identify differentially expressed genes following a 4‐h shift to high or very‐low light. A shift to high light altered the expression of over 2,000 genes, many involved with photosynthesis, PSII assembly, primary metabolism, and reactive‐oxygen scavenging. These changes are an attempt to optimize photosynthesis and increase energy sinks for excess reductant, while minimizing photooxidative stress. A transfer to very‐low light resulted in a lower photosynthetic performance and metabolic alteration, reflecting an energy‐limited state. Genes located on the nucleomorph, the vestigial nucleus in the plastid, had few changes in expression in either light treatment, indicating this organelle has relinquished most transcriptional control to the nucleus. Overall, during plastid origin, both host and transferred endosymbiont genes evolved a harmonized transcriptional network to respond to a classic photosynthetic stress.
Discrimination Experiments in Entamoeba and Evidence from Other Protists Suggest Pathogenic Amebas Cooperate with Kin to Colonize Hosts and Deter Rivals
Authors: Espinosa Avelina , Paz‐y‐Miño‐C Guillermo 
Published: July 2018

AbstractEntamoeba histolytica is one of the least understood protists in terms of taxa, clone, and kin discrimination/recognition ability. However, the capacity to tell apart same or self (clone/kin) from different or nonself (nonclone/nonkin) has long been demonstrated in pathogenic eukaryotes like Trypanosoma and Plasmodium, free‐living social amebas (Dictyostelium, Polysphondylium), budding yeast (Saccharomyces), and in numerous bacteria and archaea (prokaryotes). Kin discrimination/recognition is explained under inclusive fitness theory; that is, the reproductive advantage that genetically closely related organisms (kin) can gain by cooperating preferably with one another (rather than with distantly related or unrelated individuals), minimizing antagonism and competition with kin, and excluding genetic strangers (or cheaters = noncooperators that benefit from others’ investments in altruistic cooperation). In this review, we rely on the outcomes of in vitro pairwise discrimination/recognition encounters between seven Entamoeba lineages to discuss the biological significance of taxa, clone, and kin discrimination/recognition in a range of generalist and specialist species (close or distantly related phylogenetically). We then focus our discussion on the importance of these laboratory observations for E. histolytica's life cycle, host infestation, and implications of these features of the amebas’ natural history for human health (including mitigation of amebiasis).
Climate and organizational performance in long‐term care facilities: The role of affective commitment
Authors: Woznyj Haley M. , Heggestad Eric D. , Kennerly Susan , Yap Tracey L. 
Published: July 2018

Organizational climate represents the shared perceptions that employees have about their experiences at work. A persistent goal of the literature has been to relate organizational climate to organizational outcomes. Yet, potential mediating mechanisms of those relationships remain underexplored. This study addresses this shortcoming by exploring the mediating role of affective organizational commitment in the relationship between a climate for nursing and organizational performance. Our data included responses from a sample of 268 nurses working in 28 long‐term care facilities and multiple years of government ratings of the quality of care provided by each of those facilities. Using multilevel structural equation modelling, we found that the nurses’ affective commitment mediated the relationship between nursing climate and quality care provided both concurrently (in the same year as the data were collected) and predictively (one year later). We also found that the mediational process predicts unique variance in the lagged assessment of quality of care provided that is not accounted for by the previous year's performance. This suggests the influence of climate on affective commitment and, consequently, organizational performance may take time to become apparent. Implications for the roles of climate and affective commitment on organizational performance are discussed.Practitioner points

Our results suggest that creating a beneficial nursing climate may help organizations foster positive job attitudes, such as organizational commitment.

Creating a positive climate, like a nursing climate, and fostering job attitudes among employees, such as organizational commitment, are associated with organizational performance benefits.

The implications of a climate may not be fully realized immediately; organizational leaders driving initiatives to create a positive climate should expect it will take some time to realize benefits on organizational performance indicators.
Carbon acquisition characteristics of six microalgal species isolated from a subtropical reservoir: potential implications for species succession
Authors: Lines Thomas , Beardall John 
Published: July 2018

CO2 levels in freshwater systems can fluctuate widely, potentially influencing photosynthetic rates and growth of phytoplankton. Given the right conditions, this can lead to bloom formation and affect water quality. This study investigated the acquisition of dissolved inorganic carbon (DIC) by six species of microalgae, a cyanobacterium Cylindrospermopsis raciborskii, the diatoms Cyclotella sp., Nitzschia sp., and the green algae Stichococcus sp., Staurastrum sp., and Monoraphidium sp., all isolated from a subtropical reservoir in Australia. Carbon acquisition characteristics, specifically the affinity for DIC, internal pH, and internal DIC concentrations were measured. Affinities for CO2 () ranged between 0.7 and 6 μM CO2. This was considerably lower than air‐equilibrated surface water CO2 concentrations, and below reported affinities for CO2 of RuBisCO suggesting operation of active carbon dioxide concentrating mechanisms (CCMs) in all species. Internal pH was lowest for Cyclotella sp. at 7.19, and highest for Staurastrum sp., at 7.71. At 180 μM external DIC, ratios of internal:external CO2 ranged from 2.5 for Nitzschia sp. to 14 in C. raciborskii. Internal HCO3− concentration showed a linear relationship with surface area to biovolume ratio (SA:Vol). We hypothesized that species with a higher SA:Vol suffer more from diffusive escape of CO2, thus storage of DIC as bicarbonate is favored in these strains. For C. raciborskii, under stratified summer conditions, its strong CCM, and resilient photosynthetic characteristics may contribute to its bloom forming capacity.
The effects of contemporary selection and dispersal limitation on the community assembly of acidophilic microalgae
Authors: Hsieh Chia‐Jung , Zhan Shing Hei , Liao Chen‐Pan , Tang Sen‐Lin , Wang Liang‐Chi , Watanabe Tsuyoshi , Geraldino Paul John L. , Liu Shao‐Lun 
Published: July 2018

Extremophilic microalgae are primary producers in acidic habitats, such as volcanic sites and acid mine drainages, and play a central role in biogeochemical cycles. Yet, basic knowledge about their species composition and community assembly is lacking. Here, we begin to fill this knowledge gap by performing the first large‐scale survey of microalgal diversity in acidic geothermal sites across the West Pacific Island Chain. We collected 72 environmental samples in 12 geothermal sites, measured temperature and pH, and performed rbcL amplicon‐based 454 pyrosequencing. Using these data, we estimated the diversity of microalgal species, and then examined the relative contribution of contemporary selection (i.e., local environmental variables) and dispersal limitation on the assembly of these communities. A species delimitation analysis uncovered seven major microalgae (four red, two green, and one diatom) and higher species diversity than previously appreciated. A distance‐based redundancy analysis with variation partitioning revealed that dispersal limitation has a greater influence on the community assembly of microalgae than contemporary selection. Consistent with this finding, community similarity among the sampled sites decayed more quickly over geographical distance than differences in environmental factors. Our work paves the way for future studies to understand the ecology and biogeography of microalgae in extreme habitats.
The seasonal effects on the encrustation of charophytes in two hard‐water lakes
Authors: Herbst Anne , von Tümpling Wolf , Schubert Hendrik 
Published: July 2018

Encrustation and element content of six charophyte species from two hard‐water lakes were investigated monthly for a period of 1 year. Seasonal patterns were analyzed for the interaction of water chemistry. Encrustation followed a seasonal pattern for Chara contraria, Chara subspinosa, and Nitellopsis obtusa in Lake Krüselin and for Chara globularis and Chara tomentosa in Lake Lützlow. However, no seasonality in the precipitated CaCO3 was observed for C. subspinosa in Lake Lützlow and for C. tomentosa in Lake Krüselin, indicating a lake‐specific dependency. Species‐specific encrustation was found. Chara contraria and N. obtusa encrusted the most in June and August, whereas C. subspinosa and Nitella flexilis/opaca exhibited lowest encrustation in March and April. The precipitated CaCO3 of charophytes correlated negatively to the concentration of total inorganic carbon in both lakes. Element content of plant dry weight was species‐specific for Ca and K, and lake‐specific for Mg. No specific pattern was found for the TP and Fe contents. The results showed seasonal, species, and lake‐specific influences on the encrustation of charophytes.
Sex‐biased gene expression, sexual antagonism and levels of genetic diversity in the collared flycatcher (Ficedula albicollis) genome
Authors: Dutoit Ludovic , Mugal Carina F. , Bolívar Paulina , Wang Mi , Nadachowska‐Brzyska Krystyna , Smeds Linnéa , Yazdi Homa P. , Gustafsson Lars , Ellegren Hans 
Published: July 2018

AbstractTheoretical work suggests that sexual conflict should promote the maintenance of genetic diversity by the opposing directions of selection on males and females. If such conflict is pervasive, it could potentially lead to genomic heterogeneity in levels of genetic diversity an idea that so far has not been empirically tested on a genomewide scale. We used large‐scale population genomic and transcriptomic data from the collared flycatcher (Ficedula albicollis) to analyse how sexual conflict, for which we use sex‐biased gene expression as a proxy, relates to genetic variability. Here, we demonstrate that the extent of sex‐biased gene expression of both male‐biased and female‐biased genes is significantly correlated with levels of nucleotide diversity in gene sequences and that this correlation extends to diversity levels also in intergenic DNA and introns. We find signatures of balancing selection in sex‐biased genes but also note that relaxed purifying selection could potentially explain part of the observed patterns. The finding of significant genetic differentiation between males and females for male‐biased (and gonad‐specific) genes indicates ongoing sexual conflict and sex‐specific viability selection, potentially driven by sexual selection. Our results thus indicate that sexual antagonism could potentially be considered as one viable explanation to the long‐standing question in evolutionary biology of how genomes can remain so genetically variable in face of strong natural and sexual selection.
Alternate life history phases of a common seaweed have distinct microbial surface communities
Authors: Lemay Matthew A. , Martone Patrick T. , Hind Katharine R. , Lindstrom Sandra C. , Wegener Parfrey Laura 
Published: July 2018

AbstractMacroalgal life histories are complex, often involving the alternation of distinct free‐living life history phases that differ in morphology, longevity and ploidy. The surfaces of marine macroalgae support diverse microbial biofilms, yet the degree of microbial variation between alternate phases is unknown. We quantified bacterial (16S rRNA gene) and microeukaryote (18S rRNA gene) communities on the surface of the common intertidal seaweed, Mastocarpus spp., which alternates between gametophyte (foliose, haploid) and sporophyte (encrusting, diploid) life history phases. A large portion (97%) of bacterial taxa on the surface Mastocarpus was also present in samples from the environment, indicating that macroalgal surface communities are largely assembled from the surrounding seawater. Still, changes in the relative abundance of bacterial taxa result in significantly different communities on alternate Mastocarpus life history phases, rocky substrate and seawater at all intertidal elevations. For microeukaryote assemblages, only high intertidal samples had significant differences between life history phases although sporophytes were not different from the rocky substrate at this elevation; gametophytes and sporophytes did not differ in microeukaryote communities in the mid and low zones. By sequencing three host genes, we identified three cryptic species of Mastocarpus in our data set, which co‐occur in the mid‐to‐low intertidal zone. In these samples, M. alaskensis sporophytes harboured distinct bacterial communities compared to M. agardhii and M. intermedius sporophytes, which were not distinguishable. Conversely, microeukaryote communities did not differ among species.
Dissecting interplays between Vitis vinifera L. and grapevine virus B (GVB) under field conditions
Authors: Chitarra Walter , Cuozzo Danila , Ferrandino Alessandra , Secchi Francesca , Palmano Sabrina , Perrone Irene , Boccacci Paolo , Pagliarani Chiara , Gribaudo Ivana , Mannini Franco , Gambino Giorgio 
Published: July 2018

SummaryPlant virus infections are often difficult to characterize as they result from a complex molecular and physiological interplay between a pathogen and its host. In this study, the impact of the phloem‐limited grapevine virus B (GVB) on the Vitis vinifera L. wine‐red cultivar Albarossa was analysed under field conditions. Trials were carried out over two growing seasons by combining agronomic, molecular, biochemical and ecophysiological approaches. The data showed that GVB did not induce macroscopic symptoms on ‘Albarossa’, but affected the ecophysiological performances of vines in terms of assimilation rates, particularly at the end of the season, without compromising yield and vigour. In GVB‐infected plants, the accumulation of soluble carbohydrates in the leaves and transcriptional changes in sugar‐ and photosynthetic‐related genes seemed to trigger defence responses similar to those observed in plants infected by phytoplasmas, although to a lesser extent. In addition, GVB activated berry secondary metabolism. In particular, total anthocyanins and their acetylated forms accumulated at higher levels in GVB‐infected than in GVB‐free berries, consistent with the expression profiles of the related biosynthetic genes. These results contribute to improve our understanding of the multifaceted grapevine–virus interaction.
Richards‐Campbell sleep questionnaire: psychometric properties of Chinese critically ill patients
Authors: Chen Li‐xia , Ji Dai‐hong , Zhang Feng , Li Jian‐hua , Cui Li , Bai Chun‐jie , Liu Heng , Liang Yan 
Published: July 2018

ABSTRACTBackgroundSleep abnormalities occur frequently in critically ill patients. Nurses are strategically placed, specifically in intensive care units, to promote sleep in such patients. Currently, an effective sleep assessment tool in Chinese is not available for intensive care settings.AimThis study aimed to assess the reliability and validity of the Chinese version of the Richards‐Campbell Sleep Questionnaire (RCSQ‐C). It also aimed to evaluate patient‐nurse reliability and agreement of the RCSQ‐C in the intensive care unit (ICU).MethodsWe translated the original RCSQ into Chinese and then back‐translated it into English to ensure its accuracy of translation. Internal consistency, discrimination validity and construct validity of the RCSQ‐C were examined in 150 critically ill patients. The convergent validity of the RCSQ‐C was evaluated in 44 of 150 critically ill patients, and data from the RCSQ‐C were compared with those of the Chinese version of St Mary's Hospital Sleep Questionnaire (SMHSQ). Comparisons were also made between RCSQ‐C scores obtained from patients and their nurses.ResultsCronbach's α of the RCSQ‐C was 0.923; thus, it showed high reliability. The corrected item‐total correlation coefficient was in the range of 0·680∼0·805, which showed that the items were homogeneous for evaluating sleep. The content validity was 0·84. One factor was extracted with a cumulative contribution rate of 76·597%. Confirmatory factor analysis showed that the original single‐factor structure proposed by Richards adequately fit the data. The RCSQ‐C could discriminate poor and good sleepers, which supported discriminant validity. There was a close correlation between the scores obtained from the RCSQ patient's version and those from the SMHSQ. The intraclass correlation coefficients of the patient and nurse ranged from 0·315 to 0·609.ConclusionsThe psychometric properties of the RCSQ‐C suggest its utility in critically ill patients. Patient‐nurse reliability on the RCSQ‐C was “fair” to “substantial”, with nurses tending to overestimate patients' perceived sleep quality.Relevance to Clinical PracticeIf the validity of this questionnaire is supported in other ICU samples, RCSQ‐C could be used as a routine evaluation instrument to distinguish good and poor sleepers and then direct nurses to form corresponding treatment plans to promote sleep.
Obesity and GERD impair esophageal epithelial permeability through 2 distinct mechanisms
Authors: Blevins C. H. , Dierkhising R. A. , Geno D. M. , Johnson M. L. , Vela M. F. , Ravi K. , Iyer P. G. , Katzka D. A. 
Published: July 2018

AbstractBackgroundThe mechanism by which obesity leads to damage independent of reflux is unclear. We aimed to determine the influence of obesity on mean nocturnal baseline impedance (MNBI), a functional measure of the epithelial barrier, in the presence and absence of acid reflux, using ambulatory pH impedance measurements.MethodsTwenty‐four‐hour pH impedance studies performed off medications in Caucasian men with a normal endoscopic examination were assessed for level of acid exposure and MNBI. Four patient groups were studied: Group 1, Not obese and normal acid exposure; Group 2, Obese and normal acid exposure; Group 3, Not obese and increased acid exposure; and Group 4, Obese with increased acid exposure.ResultsOne hundred patients were studied (25 in each group). Mean esophageal mucosal impedance (MI) was substantially lower in obese patients without reflux (Group 2) and non‐obese patients with reflux (Group 3) compared to normal controls (non‐obese, no reflux, Group 1). MI was progressively lower in the distal (vs the proximal) esophagus in GER patients, compared to those without GER. This difference persisted in the presence or absence of obesity. In contrast, in obese patients, the mean MI was significantly lower throughout the esophagus when compared to the non‐obese patients and also persisted in the presence and absence of accompanying reflux. Obesity and reflux were both independently negatively correlated with MI.ConclusionObesity is associated with abnormal esophageal MNBI. In contrast to gastro‐esophageal reflux, this decrease is pan‐esophageal. These data may support a systemic mechanism by which obesity alters the esophageal barrier function.
Osmotic stress enhances suberization of apoplastic barriers in barley seminal roots: analysis of chemical, transcriptomic and physiological responses
Authors: Kreszies Tino , Shellakkutti Nandhini , Osthoff Alina , Yu Peng , Baldauf Jutta A. , Zeisler‐Diehl Viktoria V. , Ranathunge Kosala , Hochholdinger Frank , Schreiber Lukas 
Published: July 2018

SummaryBarley (Hordeum vulgare) is more drought tolerant than other cereals, thus making it an excellent model for the study of the chemical, transcriptomic and physiological effects of water deficit. Roots are the first organ to sense soil water deficit. Therefore, we studied the response of barley seminal roots to different water potentials induced by polyethylene glycol (PEG) 8000.We investigated changes in anatomical parameters by histochemistry and microscopy, quantitative and qualitative changes in suberin composition by analytical chemistry, transcript changes by RNA‐sequencing (RNA‐Seq), and the radial water and solute movement of roots using a root pressure probe.In response to osmotic stress, genes in the suberin biosynthesis pathway were upregulated that correlated with increased suberin amounts in the endodermis and an overall reduction in hydraulic conductivity (Lpr). In parallel, transcriptomic data indicated no or only weak effects of osmotic stress on aquaporin expression.These results indicate that osmotic stress enhances cell wall suberization and markedly reduces Lprof the apoplastic pathway, whereas Lprof the cell‐to‐cell pathway is not altered. Thus, the sealed apoplast markedly reduces the uncontrolled backflow of water from the root to the medium, whilst keeping constant water flow through the highly regulated cell‐to‐cell path.
PII1: a protein involved in starch initiation that determines granule number and size in Arabidopsis chloroplast
Authors: Vandromme Camille , Spriet Corentin , Dauvillée David , Courseaux Adeline , Putaux Jean‐Luc , Wychowski Adeline , Krzewinski Frédéric , Facon Maud , D'Hulst Christophe , Wattebled Fabrice 
Published: July 2018

Summary

The initiation of starch granule formation is still poorly understood. However, the soluble starch synthase 4 (SS4) appears to be a major component of this process since it is required to synthesize the correct number of starch granules in the chloroplasts of Arabidopsis thaliana plants.

A yeast two‐hybrid screen allowed the identification of several putative SS4 interacting partners. We identified the product of At4g32190 locus as a chloroplast‐targeted PROTEIN INVOLVED IN STARCH INITIATION (named PII1).

Arabidopsis mutants devoid of PII1 display an alteration of the starch initiation process and accumulate, on average, one starch granule per plastid instead of the five to seven granules found in plastids of wild‐type plants. These granules are larger than in wild‐type, and they remain flat and lenticular. pii1 mutants display wild‐type growth rates and accumulate standard starch amounts. Moreover, starch characteristics, such as amylopectin chain length distribution, remain unchanged.

Our results reveal the involvement of PII1 in the starch priming process in Arabidopsis leaves through interaction with SS4.