bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors that influence the success of small and medium-sized suppliers in public procurement: evidence from a centralized agency in Germany
Authors: Glas Andreas Herbert , Eßig Michael 
Published: February 2018

Purpose
One of the major methods to promote small- and medium-sized enterprises (SMEs) in public procurement is to split tenders into lots. The basic assumption is that SMEs have better chances of awarding smaller or more specialized contracts. This paper aims to investigate whether this widely accepted assumption is correct.

Design/methodology/approach
This article examines four hypotheses about the factors that influence SME success in public procurement. The empirical analysis uses real data from 380 contract award files and logistic regression to test the hypotheses.

Findings
The results show that a higher number of lots in a tender does not significantly increase the success rate of SMEs, and other factors, including the type of public procurement procedure, the number of participating companies and the overall tender volume, significantly influence SME success.

Research limitations/implications
There are several implications for theory and practice, including the need to further strengthen the academic evaluation of public procurement policies, the suggestion to implement SME support instruments in public legislation with the utmost caution in practice and the managerial indication that SME competitiveness is more relevant to their success in public bidding than public support policies.

Originality/value
The findings stand in fundamental contrast to the legal regulations, which postulate that lots are the driving force for SME promotion in public procurement. This is also in contrast to public procurement policies that, for many years, have recommended splitting contracts into smaller lots to become SME-friendly.
Among‐strain consistency in the pace and shape of senescence in duckweed
Authors: Barks Patrick M. , Dempsey Zach W. , Burg Theresa M. , Laird Robert A. 
Published: February 2018

Abstract

Comparative studies have demonstrated extensive variation in age trajectories of mortality and fecundity, both within and among species, with many taxa exhibiting a general pattern of age‐related demographic decline referred to as senescence. Whereas a considerable body of theory is devoted to explaining the origin and persistence of senescence, the evolutionary forces underlying variation in demographic trajectories more generally remain poorly understood.

Studying variation in demographic trajectories is complicated by the fact that different species (or even different populations of a given species) may live and reproduce on different time‐scales, which, for comparative purposes, can make it challenging to disentangle patterns of age‐related demographic change (the shape of demographic age trajectories) from the time‐scale on which those changes happen (the pace of demographic age trajectories).

Here, we examine variation in the pace and shape of demographic trajectories among strains of the aquatic plant Lemna turionifera Landolt from 24 sites across Alberta, Canada. Our main objectives were to describe the shape of demographic trajectories in L. turionifera, and test for among‐strain variation in pace and shape. We also tested whether potential variation in pace and shape is (1) constrained by trade‐offs with other life‐history traits, and (2) consistent with local adaptation to environmental characteristics at the sites of strain origin.

The strains we examined were overwhelmingly subject to age‐related increases in mortality and declines in fecundity, with increases in mortality tending to decelerate and plateau at advanced ages. Despite substantial among‐strain variation in cumulative fecundity and plant size, measures of pace and shape did not in themselves vary significantly among strains. Both within and among strains, we observed a negative relationship between plant size and the shape of fecundity trajectories, but we found no other evidence for life‐history trade‐offs involving pace or shape, nor for local adaptation.

Synthesis. Angiosperms display remarkable demographic variation. Our results suggest that the pace and shape of demographic trajectories are highly conserved within one particular angiosperm species (Lemna turionifera), despite substantial among‐strain variation in other life‐history traits.
Independent effects of host and environment on the diversity of wood‐inhabiting fungi
Authors: Krah Franz‐Sebastian , Seibold Sebastian , Brandl Roland , Baldrian Petr , Müller Jörg , Bässler Claus 
Published: February 2018

Abstract

Dead wood is a habitat for numerous fungal species, many of which are important agents of decomposition. Previous studies suggested that wood‐inhabiting fungal communities are affected by climate, availability of dead wood in the surrounding landscape and characteristics of the colonized dead‐wood object (e.g. host tree species). These findings indicate that different filters structure fungal communities at different scales, but how these factors individually drive fungal fruiting diversity on dead‐wood objects is unknown.

We conducted an orthogonal experiment comprising 180 plots (0.1 ha) in a random block design and measured fungal fruit body richness and community composition on 720 dead‐wood objects over the first 4 years of succession. The experiment allowed us to disentangle the effects of the host (beech and fir; logs and branches) and the environment (microclimate: sunny and shady plots; local dead wood: amount and heterogeneity of dead wood added to plot).

Variance partitioning revealed that the host was more important than the environment for the diversity of wood‐inhabiting fungi. A more detailed model revealed that host tree species had the highest independent effect on richness and community composition of fruiting species of fungi. Host size had significant but low independent effects on richness and community composition of fruiting species. Canopy openness significantly affected the community composition of fruiting species. By contrast, neither local amount nor heterogeneity of dead wood significantly affected the fungal diversity measures.

Synthesis. Our study identified host tree species as a more important driver of the diversity of wood‐inhabiting fungi than the environment, which suggests a host‐centred filter of this diversity in the early phase of the decomposition process. For the conservation of wood‐inhabiting fungi, a high variety of host species in various microclimates is more important than the availability of dead wood at the stand level.
Coexistence of novel gammaproteobacterial and Arsenophonus symbionts in the scale insect Greenisca brachypodii (Hemiptera, Coccomorpha: Eriococcidae)
Authors: Michalik Anna , Schulz Frederik , Michalik Katarzyna , Wascher Florian , Horn Matthias , Szklarzewicz Teresa 
Published: February 2018

SummaryScale insects are commonly associated with obligate, intracellular microorganisms which play important roles in complementing their hosts with essential nutrients. Here we characterized the symbiotic system of Greenisca brachypodii, a member of the family Eriococcidae. Histological and ultrastructural analyses have indicated that G. brachypodii is stably associated with coccoid and rod‐shaped bacteria. Phylogenetic analyses have revealed that the coccoid bacteria represent a sister group to the secondary symbiont of the mealybug Melanococcus albizziae, whereas the rod‐shaped symbionts are close relatives of Arsenophonus symbionts in insects – to our knowledge, this is the first report of the presence of Arsenophonus bacterium in scale insects. As a comparison of 16S and 23S rRNA genes sequences of the G. brachypodii coccoid symbiont with other gammaprotebacterial sequences showed only low similarity (∼90%), we propose the name ‘Candidatus Kotejella greeniscae’ for its tentative classification. Both symbionts are transovarially transmitted from one generation to the next. The infection takes place in the neck region of the ovariole. The bacteria migrate between follicular cells, as well as through the cytoplasm of those cells to the perivitelline space, where they form a characteristic ‘symbiont ball’. Our findings provide evidence for a polyphyletic origin of symbionts of Eriococcidae.
The Mirror Effect: Corporate Social Responsibility, Corporate Social Irresponsibility and Firm Performance in Coordinated Market Economies and Liberal Market Economies
Authors: Walker Kent , Zhang Zhou , Ni Na (Nina) 
Published: February 2018

AbstractWe investigate the classic management debate of agency versus institutional pressures through the application of the varieties of capitalism literature. In particular, we examine corporate social responsibility (CSR), corporate social irresponsibility (CSiR) and their relationships with firm performance in two types of capitalist systems: coordinated market economies (CMEs) and liberal market economies (LMEs). We note that while the CSR literature has tended to develop a balanced view on the influence of agency and institutional pressures, the CSiR literature has tended to emphasize the influence of agency. The latter appears to be a result of the fundamental attribution bias, where irresponsible corporate behaviours are attributed to individual managers or organizations, rather than the institutional environment. Our results, which include five years of data across 16 countries, show significantly greater CSR and significantly lower CSiR in CMEs compared with LMEs. Further, we find a positive relationship between CSR and firm performance in CMEs but not LMEs, and a negative relationship between CSiR and firm performance in LMEs but not CMEs. Overall, our results demonstrate the influence of the institutional environment, suggesting that corporate behaviours mirror the external environment.
Substrate and electron donor limitation induce phenotypic heterogeneity in different metabolic activities in a green sulphur bacterium
Authors: Zimmermann M. , Escrig S. , Lavik G. , Kuypers M. M. M. , Meibom A. , Ackermann M. , Schreiber F. 
Published: February 2018

SummaryPopulations of genetically identical cells can display marked variation in phenotypic traits; such variation is termed phenotypic heterogeneity. Here, we investigate the effect of substrate and electron donor limitation on phenotypic heterogeneity in N2 and CO2 fixation in the green sulphur bacterium Chlorobium phaeobacteroides. We grew populations in chemostats and batch cultures and used stable isotope labelling combined with nanometer‐scale secondary ion mass spectrometry (NanoSIMS) to quantify phenotypic heterogeneity. Experiments in H2S (i.e. electron donor) limited chemostats show that varying levels of
limitation induce heterogeneity in N2 fixation. Comparison of phenotypic heterogeneity between chemostats and batch (unlimited for H2S) populations indicates that electron donor limitation drives heterogeneity in N2 and CO2 fixation. Our results demonstrate that phenotypic heterogeneity in a certain metabolic activity can be driven by different modes of limitation and that heterogeneity can emerge in different metabolic processes upon the same mode of limitation. In conclusion, our data suggest that limitation is a general driver of phenotypic heterogeneity in microbial populations.
Regulation of σ factors by conserved partner switches controlled by divergent signalling systems
Authors: Bouillet Sophie , Arabet Dallel , Jourlin‐Castelli Cécile , Méjean Vincent , Iobbi‐Nivol Chantal 
Published: February 2018

SummaryPartner‐Switching Systems (PSS) are widespread regulatory systems, each comprising a kinase‐anti‐σ, a phosphorylatable anti‐σ antagonist and a phosphatase module. The anti‐σ domain quickly sequesters or delivers the target σ factor according to the phosphorylation state of the anti‐σ antagonist induced by environmental signals. The PSS components are proteins alone or merged to other domains probably to adapt to the input signals. PSS are involved in major cellular processes including stress response, sporulation, biofilm formation and pathogenesis. Surprisingly, the target σ factors are often unknown and the sensing modules acting upstream from the PSS diverge according to the bacterial species. Indeed, they belong to either two‐component systems or complex pathways as the stressosome or Chemosensory Systems (CS). Based on a phylogenetic analysis, we propose that the sensing module in Gram‐negative bacteria is often a CS.
Simulation‐based point‐of‐care ultrasound training: a matter of competency rather than volume
Authors: Jensen J. K. , Dyre L. , Jørgensen M. E. , Andreasen L. A. , Tolsgaard M. G. 
Published: February 2018

BackgroundPoint‐of‐care ultrasonography plays an increasingly important role in the initial resuscitation of critically ill patients but acquisition of the skill is associated with long learning curves. The skills required to perform ultrasound examinations can be practiced in a simulated setting before being performed on actual patients. The aim of this study was to investigate the learning curves for novices training the FAST protocol on a virtual‐reality simulator.MethodsUltrasound novices (N = 25) were instructed to complete a FAST training program on a virtual‐reality ultrasound simulator. Participants were instructed to continue training until they reached a previously established mastery learning level, which corresponds to the performance level of a group of ultrasound experts. Performance scores and time used during each FAST examination were used to determine participants’ learning curves.ResultsThe participants attained the mastery learning level within a median of three (range two to four) attempts corresponding to a median of 1 h 46 min (range 1 h 2 min to 3 h 37 min) of simulation training. The ultrasound novices’ examination speed improved significantly with training, and continued to improve even after they attained the mastery learning level (P = 0.011). Twenty‐three participants attained the mastery learning level.ConclusionNovices can attain mastery learning levels using simulation‐based ultrasound training with less than, on average, 2 h of practice. However, we found large variations in the amount of training needed, which raises questions about the adequacy of current volume‐based models for determining ultrasound competency.
Yellow, red, dead: the nutritional consequences for Cardiaspina densitexta (Hemiptera: Aphalaridae) nymphs of inducing senescence in old Eucalyptus fasciculosa leaves
Authors: Steinbauer Martin J , Salminen Juha‐Pekka , Watson Simon J 
Published: February 2018

AbstractMany psyllids are manipulative herbivores that alter their hosts to provide shelter and ameliorate nutritional quality. Among eucalypt‐feeding psyllids, Cardiaspina have specialised to manipulate natural processes of foliar senescence and thereby host nutritional quality but not foliar morphology. Using a natural outbreak, we assessed the effects of feeding by nymphs of Cardiaspina densitexta Taylor, ultraviolet exposure and temperature on changes in nutritional quality and leaf abscission. Over 6 months, we followed the responses of tagged Eucalyptus fasciculosa F.Muell. leaves that, at the beginning of the study, were at one of three different stages of utilisation by psyllids (no psyllids, only eggs present, or leaves with late instar nymphs and red lesions). We measured foliar pigments, free amino acids and polyphenols every second month to characterise foliar nutritional quality. Psyllid feeding was briefly associated with chlorosis but lesions rapidly turned red (anthocyanic) and died after nymphs had matured. Red leaves had shortened longevities and their risk of abscission was positively correlated with the UV‐index rating of the preceding fortnight but not with psyllid abundance or area necrotic. Hence, psyllids altered the balance of chlorophylls and anthocyanin‐equivalents of green leaves and presumably therefore their ability to fully utilise incoming light energy. Green leaves had distinct free amino acids and polyphenol compositions compared to red leaves. In green leaves, changes in anthocyanin‐equivalents were negatively correlated with methionine while in red leaves psyllids were positively correlated with threonine and negatively correlated with leucine. Feeding by Cardiaspina densitexta nymphs is associated with the visible symptoms of photodamage which are associated with pronounced changes in nutritional quality. These changes are not analogous to foliar hypersensitive responses because they are expressed by old leaves, necrotic tissues are not abscised, they occur late in the development of nymphs and do not directly affect their survival. Specialisation of Cardiaspina on old eucalypt leaves may appear maladaptive if these modules are considered to be low in amino nitrogen and high in polyphenols. This perspective needs refining given the influence of photodamage on nutrient availability and because condensed tannins (weak pro‐oxidants) are more abundant than hydrolysable tannins in old leaves.
Arm morbidity of axillary dissection with sentinel node biopsy versus delayed axillary dissection
Authors: Ballal Helen , Hunt Catherine , Bharat Chrianna , Murray Kevin , Kamyab Roshi , Saunders Christobel 
Published: February 2018

BackgroundStaging of axillary lymph nodes in breast cancer is important for prognostication and planning of adjuvant therapy. The traditional practice of proceeding to axillary lymph node dissection (ALND) if sentinel lymph node biopsy (SLNB) is positive is being challenged and clinical trials are underway. For many centres, this will mean a move away from intra‐operative SLNB assessment and utilization of a second procedure to perform ALND. It is sometimes perceived that a delayed ALND results in increased tissue damage and thus increased morbidity. We compared morbidity in those undergoing SLNB only, or ALND as a one‐ or two‐stage procedure.MethodsA retrospective review of a prospectively collected institutional database was used to review rates of lymphoedema and shoulder function in women undergoing breast cancer surgery between 2008 and 2012.ResultsThe overall lymphoedema rate in 745 patients was 8.2% at 12 months. There was no difference in lymphoedema rates between those undergoing immediate or delayed ALND (17.8 and 8.6%, respectively, P = 0.092). Post‐operative shoulder elevation, odds ratio (OR) = 0.390, 95% confidence interval (CI) = (0.218, 0.698) and abduction, OR = 0.437 (95% CI = (0.271, 0.705)) were reduced if an ALND was performed although there was no difference between immediate or delayed.ConclusionALND remains a risk factor for post‐operative morbidity. There is no increased risk of lymphoedema or shoulder function deficit with a positive SLNB and delayed ALND compared to immediate ALND.
Presenilin PS1∆E9 disrupts mobility of secretory organelles in rat astrocytes
Authors: Stenovec M. , Trkov Bobnar S. , Smolič T. , Kreft M. , Parpura V. , Zorec R. 
Published: February 2018

AbstractAimAlzheimer's disease (AD) is largely considered a neuron‐derived insult, but also involves failure of astroglia. A recent study indicated that mutated presenilin 1 (PS1M146V), a putative endoplasmic reticulum (ER) Ca2+ channel with decreased Ca2+ conductance, impairs the traffic of astroglial peptidergic vesicles. Whether other pathogenically relevant PS1 mutants, such as PS1ΔE9, which code for ER channel with putative increased Ca2+ conductance, similarly affect vesicle traffic, is unknown.MethodsHere, we cotransfected rat astrocytes with plasmids encoding mutant PS1ΔE9 and atrial natriuretic peptide or vesicular glutamate transporter 1 tagged with fluorescent proteins (pANP.emd or pVGLUT1‐EGFP respectively), to microscopically examine whether alterations in vesicle mobility and Ca2+‐regulated release of gliosignalling molecules manifest as a general vesicle‐based defect; control cells were transfected to co‐express exogenous or native wild‐type PS1 and pANP.emd or pVGLUT1‐EGFP. The vesicle mobility was analysed at rest and after ATP stimulation that increased intracellular calcium activity.ResultsIn PS1ΔE9 astrocytes, spontaneous mobility of both vesicle types was reduced (P < .001) when compared to controls. Post‐stimulatory recovery of fast vesicle mobility was hampered in PS1ΔE9 astrocytes. The ATP‐evoked peptide release was less efficient in PS1ΔE9 astrocytes than in the controls (P < .05), as was the pre‐stimulatory mobility of these vesicles.ConclusionAlthough the PS1 mutants PS1M146V and PS1ΔE9 differently affect ER Ca2+ conductance, our results revealed a common, vesicle‐type indiscriminate trafficking defect in PS1ΔE9 astrocytes, indicating that reduced secretory vesicle‐based signalling is a general deficit in AD astrocytes.
Hypolipidemic and anti‐inflammatory effects of aorta and heart tissues of cattle and pigs in the atherosclerosis rat model
Authors: Chernukha Irina M. , Fedulova Liliya V. , Kotenkova Elena A. , Takeda Shiro , Sakata Ryoichi 
Published: February 2018

AbstractThe aim of this study was to investigate the effects of aorta and heart tissues obtained from cattle and pigs on atherosclerosis disorders. Atherosclerosis model rats were provided with the respective diets consisting of aorta and heart tissues. Administration of each tissue suppressed body weight gain as compared to that of the control. In particular, the aorta tissues of pigs and cattle demonstrated significant suppressions in body weight gain in the model rats. The aorta tissues of pigs and cattle showed a significant increase and decrease in the serum high‐density lipoproteins and atherogenic index, respectively, which was correlated with the increase in apolipoprotein A1. Hematological analysis revealed that aorta tissues of pigs and cattle clearly reduced the ratio of granulocytes/lymphocytes in the atherosclerosis rats. Serum vascular cellular adhesion molecule‐1 levels in the atherosclerosis rats, which were administered these aorta tissues, were also significantly reduced. Additionally, there was an increase in von Willebrand factor in the rat serum. Based on the results obtained, the aorta tissues of pigs and cattle, in particular, demonstrated positive effects in the atherosclerosis rats due to the alteration of lipid metabolism and reduction in inflammation related to atherosclerosis.
The pharmacodynamic and clinical trial evidence for statin dose
Authors: Dimmitt Simon B. , Stampfer Hans G. , Warren John B. 
Published: February 2018

AbstractStatin doses around estimated effective dose 50 (ED50) can reduce myocardial infarction by over 25% and mortality by around 10%. Being a competitive enzyme inhibitor, statin efficacy plateaus at doses that are multiples above the ED50, whilst on‐ and off‐target adverse events increase in number and severity with increasing dose. For example, myopathy has been shown to increase by up to 29‐fold and liver dysfunction by up to nine‐fold as statin dose is increased. Doses of up to 40‐fold ED50 have been promoted, but above five‐fold ED50, for example 10 mg of atorvastatin, there is no randomized controlled clinical trial evidence that coronary mortality is lowered, or that survival is increased.