bluuebunny/crossref_metadata_2025_split huggingface dataset:
The mussel filter–pump – present understanding, with a re‐examination of gill preparations
Authors: Riisgård Hans Ulrik , Funch Peter , Larsen Poul S. 
Published: December 2014

AbstractFilter feeding in mussels is a secondary adaptation where the gills have become W‐shaped and greatly enlarged, acting as the mussel filter–pump. Water pumping and particle capture in the blue mussel, Mytilus edulis, have been studied over many years. Here, we give a short status of the present understanding of ciliary structure and function of the mussel filter–pump, supplemented with new photo‐microscope and scanning electron microscopy (SEM) pictures of gill preparations. Pumping rate (filtration) and pressure to maintain flow have been extensively studied so the power delivered by the mussel pump to the water flow is known (1.1% of total respiratory power), but the actual cost based on gill respiration is much higher (19%), implying that the cost of maintaining of the large gill pump is considerable and that only relatively little energy can be saved by stopping or reducing the activity of the water‐pumping cilia so that continuous feeding with a ‘minimal scaled’ pump is cheaper than discontinuous feeding with a correspondingly larger pump. According to the present view, the pump proper is the beating lateral cilia (lc) on the gill filaments and particle capture is accomplished by the action of laterofrontal cirri (lfc) transferring particles from the main water current to the frontal gill filament currents driven by frontal cilia (fc). Unexplained aspects include retention efficiency according to particle size and the role of pro‐laterofrontal cilia (p‐lfc) placed between the lfc and fc. The structure of cilia and the mode of ciliary beating have been re‐examined in this study by new high‐resolution light and scanning electron microscopy of isolated gill preparations exposed to serotonin (5‐HT) stimulation which can activate the lc and lfc at low concentrations (10−6 M), but removes the lfc from the interfilament canals at higher concentrations (10−5 M).
In Rasmussen Encephalitis, Hemichannels Associated with Microglial Activation are linked to Cortical Pyramidal Neuron Coupling: A Possible Mechanism for Cellular Hyperexcitability
Authors: Cepeda Carlos , Chang Julia W. , Owens Geoffrey C. , Huynh My N. , Chen Jane Y. , Tran Conny , Vinters Harry V. , Levine Michael S. , Mathern Gary W. 
Published: December 2014

SummaryAimsRasmussen encephalitis (RE) is a rare but devastating condition, mainly in children, characterized by sustained brain inflammation, atrophy of one cerebral hemisphere, epilepsy, and progressive cognitive deterioration. The etiology of RE‐induced seizures associated with the inflammatory process remains unknown.MethodsCortical tissue samples from children undergoing surgical resections for the treatment of RE (n = 16) and non‐RE (n = 12) were compared using electrophysiological, morphological, and immunohistochemical techniques to examine neuronal properties and the relationship with microglial activation using the specific microglia/macrophage calcium‐binding protein, IBA1 in conjunction with connexins and pannexin expression.ResultsCompared with non‐RE cases, pyramidal neurons from RE cases displayed increased cell capacitance and reduced input resistance. However, neuronal somatic areas were not increased in size. Instead, intracellular injection of biocytin led to increased dye coupling between neurons from RE cases. By Western blot, expression of IBA1 and pannexin was increased while connexin 32 was decreased in RE cases compared with non‐RE cases. IBA1 immunostaining overlapped with pannexin and connexin 36 in RE cases.ConclusionsIn RE, these results support the notion that a possible mechanism for cellular hyperexcitability may be related to increased intercellular coupling from pannexin linked to increased microglial activation. Such findings suggest that a possible antiseizure treatment for RE may involve the use of gap junction blockers.
A Tale of Two Factions: Why and When Factional Demographic Faultlines Hurt Board Performance
Authors: Veltrop Dennis B. , Hermes Niels , Postma Theo J. B. M. , de Haan Jakob 
Published: December 2014

AbstractManuscript TypeEmpiricalResearch Question/IssueThe authors posit that to understand the effects of board demographic diversity on board performance, it is critical to recognize that board members often do not come to a board as independent entities but rather as delegates of specific interest groups so that the board has factions. The authors propose that demographic differences between these factions are likely to negatively affect board performance through social categorization processes.Research Findings/InsightA study of 318 Dutch pension fund boards shows that factional demographic faultlines negatively affect board performance, measured as perceived board effectiveness, and financial return on investment, through the perception of board members that the board is split into factional subgroups (i.e., faultline activation). At the same time, the disruptive effects from factional demographic faultlines are found to be reduced by board reflexivity.Theoretical/Academic ImplicationsBased on social categorization theory, this study shows that demographic faultlines between factions affect board performance to the extent that the faultlines are activated. If unnoticed by board members, demographic faultlines are unlikely to influence board behavior. The attenuating effect of board reflexivity underlines the importance of insight into the factors that drive social categorization within boards.Practitioner/Policy ImplicationsPractitioners should be aware that although factional demographic faultlines can be disruptive, there are ways to reduce these negative aspects. By overtly reflecting on board processes, board members can prevent factional demographic faultlines from resulting in social categorization within boards.
Packet randomized experiments for eliminating classes of confounders
Authors: Pavela Greg , Wiener Howard , Fontaine Kevin R. , Fields David A. , Voss Jameson D. , Allison David B. 
Published: December 2014

AbstractBackgroundAlthough randomization is considered essential for causal inference, it is often not possible to randomize in nutrition and obesity research. To address this, we develop a framework for an experimental design—packet randomized experiments (PREs), which improves causal inferences when randomization on a single treatment variable is not possible. This situation arises when subjects are randomly assigned to a condition (such as a new roommate) which varies in one characteristic of interest (such as weight), but also varies across many others. There has been no general discussion of this experimental design, including its strengths, limitations, and statistical properties. As such, researchers are left to develop and apply PREs on an ad hoc basis, limiting its potential to improve causal inferences among nutrition and obesity researchers.MethodsWe introduce PREs as an intermediary design between randomized controlled trials and observational studies. We review previous research that used the PRE design and describe its application in obesity‐related research, including random roommate assignments, heterochronic parabiosis, and the quasi‐random assignment of subjects to geographic areas. We then provide a statistical framework to control for potential packet‐level confounders not accounted for by randomization.ResultsPacket randomized experiments have successfully been used to improve causal estimates of the effect of roommates, altitude, and breastfeeding on weight outcomes. When certain assumptions are met, PREs can asymptotically control for packet‐level characteristics. This has the potential to statistically estimate the effect of a single treatment even when randomization to a single treatment did not occur.ConclusionsApplying PREs to obesity‐related research will improve decisions about clinical, public health, and policy actions insofar as it offers researchers new insight into cause and effect relationships among variables.
Dark diversity in dry calcareous grasslands is determined by dispersal ability and stress‐tolerance
Authors: Riibak Kersti , Reitalu Triin , Tamme Riin , Helm Aveliina , Gerhold Pille , Znamenskiy Sergey , Bengtsson Karin , Rosén Ejvind , Prentice Honor C. , Pärtel Meelis 
Published: December 2014

Temperate calcareous grasslands are characterized by high levels of species richness at small spatial scales. Nevertheless, many species from a habitat‐specific regional species pool may be absent from local communities and represent the ‘dark diversity’ of these sites. Here we investigate dry calcareous grasslands in northern Europe to determine what proportion of the habitat‐specific species pool is realized at small scales (i.e. how the community completeness varies) and which mechanisms may be contributing to the relative sizes of the observed and dark diversity. We test whether the absence of particular species in potentially suitable grassland sites is a consequence of dispersal limitation and/or a low ability to tolerate stress (e.g. drought and grazing).We analysed a total of 1223 vegetation plots (1 × 1 m) from dry calcareous grasslands in Sweden, Estonia and western Russia. The species co‐occurrence approach was used to estimate the dark diversity for each plot. We calculated the maximum dispersal distance for each of the 291 species in our dataset by using simple plant traits (dispersal syndrome, growth form and seed characteristics). Large seed size was used as proxy for small seed number; tall plant height and low S‐strategy type scores were used to characterise low stress‐tolerance.Levels of small‐scale community completeness were relatively low (more species were absent than present) and varied between the grasslands in different geographic areas. Species in the dark diversity were generally characterized by shorter dispersal distances and greater seed weight (fewer seeds) than species in the observed diversity. Species within the dark diversity were generally taller and had a lower tolerance of stressful conditions.We conclude that, even if temperate grasslands have high levels of small‐scale plant diversity, the majority of potentially suitable species in the regional species pool may be absent as a result of dispersal limitation and low stress‐tolerance.
Influence of melaleuca and copaiba oils on Candida albicans adhesion
Authors: Tobouti Priscila Lie , Mussi Maria Carolina Martins , Rossi Diego Conrado Pereira , Pigatti Fernanda Mombrini , Taborda Carlos Pelleschi , de Assis Taveira Luiz Antônio , de Sousa Suzana Cantanhede Orsini Machado 
Published: December 2014

ObjectiveTo evaluate the efficacy of Melaleuca alternifolia and Copaifera officinalis in inhibiting the adhesion of Candida albicans biofilm.BackgroundOver 65% of denture wearers suffer from denture stomatitis, which is one of the most prevalent forms of oral candidiasis. This disease is characterised by the inflammation of the oral mucosa in contact with the contaminated denture. The contaminated denture contributes to the switch of C. albicans from yeast to its pathogenic hyphal form. Candida albicans adheres and colonises the polymethylmethacrylate resin surfaces and thus contributes to the development of denture stomatitis.Materials and methodsThe minimal inhibitory concentration (MIC) of M. alternifolia and Co. officinalis was assessed by the agar dilution method. Sixty‐six thermopolymerised acrylic resin squares were used and treated with phosphate‐buffered saline, sodium hypochlorite 1%, melaleuca 0.75%, melaleuca 0.375%, melaleuca 0.188% and copaiba 10%. For adherence and biofilm formation, the treated squares were placed in six‐well tissue culture plates containing 1 × 107 cells/ml of ATCC1023 or SC5314 in Roswell Park Memorial Institute (RPMI) medium, and after 12 h, the planktonic cells were counted.ResultsCopaiba oil did not inhibit C. albicans growth. However, melaleuca oil showed an MIC value of 0.375% (3.4 mg/ml) for ATCC10231 and 0.093% (0.84 mg/ml) for SC5314.ConclusionsOur results demonstrated that M. alternifolia oil inhibited the growth of C. albicans. Moreover, both oils promoted significant adhesion reduction in the tested strains. These findings suggest the possibility of using these oils in prophylaxes against candidiasis.
High Transparency Nd: Y2O3 Ceramics Prepared with La2O3 and ZrO2 Additives
Authors: Zhang Lei , Huang Zuocai , Pan Wei 
Published: December 2014

High transparency Nd: Y2O3 ceramics were prepared by vacuum sintering with La2O3 and ZrO2 sintering additives. The optimum in‐line transmittance of the sintered Nd: Y2O3 is 80.98% at the wavelength of 1100 nm, for which the content of La2O3 and ZrO2 are 10.0 and 3.0 at.%, respectively. This specimen demonstrates homogeneous microstructure with the average grain size of 8.3 μm. The mechanism of sintering with La2O3 and ZrO2 aids and the optical properties was discussed. The absorption, emission cross section, and fluorescence lifetime have been estimated as 1.62 × 10−20 cm2, 5.13 × 10−20 cm2, and 232 μs, respectively. Vickers hardness and the fracture toughness were measured of 9.18 GPa and 1.03 Mpa·m1/2, respectively. All the results indicate that Nd: Y2O3 transparent ceramic is a promising candidate for laser material.
The rhetoric of patient and family centred care: an institutional ethnography into what actually happens
Authors: Rankin Janet M. 
Published: December 2014

AbstractAimsThis paper uses Dorothy Smith's institutional ethnography to examine technological advances designed to improve nurses’ work. The analysis interrogates how nurses’ work is coordinated, in disquieting ways, in an apparent commitment to ‘patient and family centred care’.BackgroundThe discussion is part of a larger programme of research that focuses ethnographic attention on nurses’ activating technological managerial improvement strategies.DesignThis discussion paper describes suboptimal hospital experiences to show how they were organized. The institutional ethnographic analysis addresses discrepancies that arise between the different organizational standpoints. Overall the discussion focuses on how institutional ethnographers enquire into people's everyday activities to discover and make understandable, in the material world, what actually happens that shapes them.Data sourcesData include observations and interviews with nurses, nurse managers, patients and families. It also includes screenshots of computer fields and other documents being used by nurses.Implications for nursingNursing work is methodically being oriented to interests that undermine nurses’ capacity to contribute their knowledgeable activity to intervene in people's health and well‐being.ConclusionNurses’ work is overwhelmed with the imperative to discharge patients. This happens with an ideological construction of patient centred care that obscures what is actually happening.
On feeling good at work: the role of regulatory mode and passion in psychological adjustment
Authors: Bélanger Jocelyn J. , Pierro Antonio , Kruglanski Arie W. , Vallerand Robert J. , De Carlo Nicola , Falco Alessandra 
Published: December 2014

AbstractThe major postulate of this work is that regulatory modes influence the type of passion people experience with regard to an activity, which in turn influences their psychological adjustment. Integrating regulatory mode theory and the dualistic model of passion, we hypothesized that locomotion—associated with intrinsic and autonomous motivations—would positively predict harmonious passion, which in turn would enhance workers' psychological adjustment. In contrast, we hypothesized that assessment—associated with extrinsic and non‐autonomous motivations—would positively predict obsessive passion, which in turn would reduce workers' psychological adjustment. Two field studies supported these hypotheses with psychological adjustment measures of stress (Study 1) and burnout (Study 2) in different work contexts.
Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index
Authors: BESSELING T.H. , JOSE J. , BLAADEREN A. VAN 
Published: December 2014

SummaryAccurate distance measurement in 3D confocal microscopy is important for quantitative analysis, volume visualization and image restoration. However, axial distances can be distorted by both the point spread function (PSF) and by a refractive‐index mismatch between the sample and immersion liquid, which are difficult to separate. Additionally, accurate calibration of the axial distances in confocal microscopy remains cumbersome, although several high‐end methods exist. In this paper we present two methods to calibrate axial distances in 3D confocal microscopy that are both accurate and easily implemented. With these methods, we measured axial scaling factors as a function of refractive‐index mismatch for high‐aperture confocal microscopy imaging. We found that our scaling factors are almost completely linearly dependent on refractive index and that they were in good agreement with theoretical predictions that take the full vectorial properties of light into account. There was however a strong deviation with the theoretical predictions using (high‐angle) geometrical optics, which predict much lower scaling factors. As an illustration, we measured the PSF of a correctly calibrated point‐scanning confocal microscope and showed that a nearly index‐matched, micron‐sized spherical object is still significantly elongated due to this PSF, which signifies that care has to be taken when determining axial calibration or axial scaling using such particles.
Quantitative positron emission tomography of mGluR5 in rat brain with [18F]PSS232 at minimal invasiveness and reduced model complexity
Authors: Müller Herde Adrienne , Keller Claudia , Milicevic Sephton Selena , Mu Linjing , Schibli Roger , Ametamey Simon M. , Krämer Stefanie D. 
Published: December 2014

AbstractImaging the density of metabotropic glutamate receptor 5 (mGluR5) in brain by positron emission tomography (PET) is of interest in relation to several brain disorders. We have recently introduced [18F]PSS232, an F‐18‐labeled analog of the mGluR5‐targeting [11C]ABP688. Quantitative PET requires kinetic modeling with an input function (IF) or an appropriate reference tissue model. We aimed at minimizing invasiveness of IF recording in rat and employing this protocol for mGluR5 quantitative PET with [18F]PSS232. We further aimed at defining models of low complexity for quantitative PET with [18F]PSS232. The IF was recorded in an arterio‐venous shunt applied by minimally invasive cannulation. PET data were analyzed with a modified two‐tissue compartment model including a single variable for radiometabolite correction in brain. We further evaluated a simple reference tissue model. Receptor‐dependent accumulation was similar to [11C]ABP688 at lower unspecific accumulation of unchanged [18F]PSS232, in agreement with its higher plasma protein binding and lower lipophilicity. The minimally invasive protocol revealed similar results as the invasive shunt method and parameters calculated with the modified two‐tissue compartment model were similar to those calculated with the standard model. The simple area under the curve ratios agreed with the Logan reference method. [18F]PSS232 is a promising radioligand for mGluR5 quantification.
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Methods were evaluated to quantify mGluR5 in rat brain by PET with [18F]PSS232. We present a minimally invasive protocol for input function recording. A two‐tissue compartment model correcting for radiometabolites at reduced complexity is compared with the standard model. Finally, we demonstrate and explain why for [18F]PSS232 the area‐under‐the‐curve ratio is a valid alternative to the Logan reference tissue analysis.
Sigma receptor 1 activation attenuates release of inflammatory cytokines MIP1γ, MIP2, MIP3α, and IL12 (p40/p70) by retinal Müller glial cells
Authors: Shanmugam Arul , Wang Jing , Markand Shanu , Perry Richard L. , Tawfik Amany , Zorrilla Eric , Ganapathy Vadivel , Smith Sylvia B. 
Published: December 2014

AbstractThe high‐affinity sigma receptor 1 (σR1) ligand (+)‐pentazocine ((+)‐PTZ) affords profound retinal neuroprotection in vitro and in vivo by a yet‐unknown mechanism. A common feature of retinal disease is Müller cell reactive gliosis, which includes cytokine release. Here, we investigated whether lipopolysaccharide (LPS) stimulates cytokine release by primary mouse Müller cells and whether (+)‐PTZ alters release. Using a highly sensitive inflammatory antibody array we observed significant release of macrophage inflammatory proteins (MIP1γ, MIP2, MIP3α) and interleukin‐12 (IL12 (p40/p70)) in LPS‐treated cells compared to controls, and a significant decrease in secretion upon (+)‐PTZ treatment. Müller cells from σR1 knockout mice demonstrated increased MIP1γ, MIP2, MIP3α and IL12 (p40/p70) secretion when exposed to LPS compared to LPS‐stimulated WT cells. We investigated whether cytokine secretion was accompanied by cytosolic‐to‐nuclear NFκB translocation and whether endothelial cell adhesion/migration was altered by released cytokines. Cells exposed to LPS demonstrated increased NFκB nuclear location, which was reduced significantly in (+)‐PTZ‐treated cells. Media conditioned by LPS‐stimulated‐Müller cells induced leukocyte‐endothelial cell adhesion and endothelial cell migration, which was attenuated by (+)‐PTZ treatment. The findings suggest that release of certain inflammatory cytokines by Müller cells can be attenuated by σR1 ligands providing insights into the retinal neuroprotective role of this receptor.
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A common feature of retinal disease is Müller cell reactive gliosis, which includes cytokine release. To understand how sigma receptor 1 (σR1) mediates neuroprotection, we examined the effects of a high‐affinity σR1 ligand, (+)‐pentazocine, on LPS‐stimulated cytokine release in primary mouse retinal Müller glial cells. Under basal conditions, cytokine release was minimal. LPS stimulation markedly increased secretion of the cytokines MIP1γ, MIP2, MIP3α, IL12 (p40/p70), which was accompanied by a significant translocation of NFκB from cytoplasm to the nucleus. LPS‐treatment in the presence of (+)‐pentazocine markedly decreased cytokine release accompanied by a significant decrease in NFκB localized to the nucleus. IL, interleukin; MIP, macrophage inflammatory proteins.