bluuebunny/crossref_metadata_2025 huggingface dataset:
NADPH oxidases in oxidant production by microglia: activating receptors, pharmacology and association with disease
Authors: Haslund‐Vinding J , McBean G , Jaquet V , Vilhardt F
Published: January 2016

Microglia are the resident immune cells of the CNS and constitute a self‐sustaining population of CNS‐adapted tissue macrophages. As mononuclear phagocytic cells, they express high levels of superoxide‐producing NADPH oxidases (NOX). The sole function of the members of the NOX family is to generate reactive oxygen species (ROS) that are believed to be important in CNS host defence and in the redox signalling circuits that shape the different activation phenotypes of microglia. NOX are also important in pathological conditions, where over‐generation of ROS contributes to neuronal loss via direct oxidative tissue damage or disruption of redox signalling circuits. In this review, we assess the evidence for involvement of NOX in CNS physiopathology, with particular emphasis on the most important surface receptors that lead to generation of NOX‐derived ROS. We evaluate the potential significance of the subcellular distribution of NOX isoforms for redox signalling or release of ROS to the extracellular medium. Inhibitory mechanisms that have been reported to restrain NOX activity in microglia and macrophages in vivo are also discussed. We provide a critical appraisal of frequently used and recently developed NOX inhibitors. Finally, we review the recent literature on NOX and other sources of ROS that are involved in activation of the inflammasome and discuss the potential influence of microglia‐derived oxidants on neurogenesis, neural differentiation and culling of surplus progenitor cells. The degree to which excessive, badly timed or misplaced NOX activation in microglia may affect neuronal homeostasis in physiological or pathological conditions certainly merits further investigation.

Linked Articles

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc
Periodic Protrusion of Right Coronary Cusp into Left Ventricular Outflow Tract Due to Detachment from the Aortic Annulus Complicated with Infective Endocarditis
Authors: Tokuda Hanako , Murata Mitsushige , Yashima Fumiyuki , Kudo Mikihiko , Tsuruta Hikaru , Okamoto Kazuma , Maekawa Yuichiro , Sano Motoaki , Fukushima Hiroyuki , Shimizu Hideyuki , Fukuda Keiichi
Published: January 2016

We describe the imaging of unusual dislocation of right coronary cusp into left ventricular outflow tract (LVOT) due to the infective endocarditis. Although the two‐dimensional echocardiography identified a protruding mass in LVOT, the three‐dimensional echocardiography precisely demonstrated the spatial anatomy of the aortic root, which was confirmed by the surgical operation, implicating the usefulness of three‐dimensional echocardiography in this rare anomaly.
Semiautomatic Evaluation of Tricuspid Annular Plane Systolic Excursion from Two Dimensional Echocardiographic Images
Authors: Ramamurthy Senthil , Kelleman Michael S. , McGaughy Falon , Sachdeva Ritu
Published: January 2016

Background

Tricuspid annular plane systolic excursion (TAPSE) has emerged as a reliable marker of right ventricular (RV) systolic function. Recently, TAPSE derived using 2D images (2D‐TAPSE) was shown to correlate with M‐mode TAPSE (MM‐TAPSE). We have developed a novel technique for semiautomatic evaluation of TAPSE (SA‐TAPSE). The purpose of this study was to determine the accuracy of this novel technique and validate it on normal hearts and pulmonary hypertension (PH).

Methods

A total of 110 patients (56 with normal heart and 54 with PH) were retrospectively identified for analysis. The semiautomatic algorithm tracked the lateral tricuspid valve hinge point (TVHP) and the apex in the apical 4‐chamber view. SA‐TAPSE was calculated as displacement of the TVHP in end‐diastole (ED) and end‐systole (ES). The same points were manually identified to derive 2D‐TAPSE.

Results

The system was able to accurately identify ED and ES in 304/330 heartbeats within three cardiac frames. The automatically identified TVHP points were within 1.2 ± 0.7 mm from the manually identified points. Intra‐class correlation between SA‐TAPSE and 2D‐TAPSE was 0.96 (95% CI 0.93–0.98) for normal hearts and 0.92 (95% CI 0.87–0.96) for those with PH. Bland–Altman analysis showed a strong agreement between SA‐TAPSE and 2D‐TAPSE for normal hearts and those with PH.

Conclusion

Using the novel custom‐made software, SA‐TAPSE could be measured in majority of our patients and was accurate when applied to normal hearts and those with PH. Future work will focus on fully automating the system for a rapid retrospective analysis of TAPSE.
Effects of Rag1 aphid‐resistant soybean on mortality, development, and preference of brown marmorated stink bug
Authors: Rich Walter A. , Koch Robert L.
Published: January 2016

The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), poses a new threat to soybean, Glycine max (L.) Merrill (Fabaceae), production in the north central USA. As H. halys continues to spread and increase in abundance in the region, the interaction between H. halys and management tactics deployed for other pests must be determined. Currently, the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is the most abundant and damaging insect pest of soybean in the region. Aphid‐resistant soybean, mainly with the Rag1 gene, is commercially available for management of A. glycines. Here, experiments were performed to evaluate the effects of Rag1 aphid‐resistant soybean on the mortality, development, and preference of H. halys. In a no‐choice test, mortality of H. halys reared on Rag1 aphid‐resistant soybean pods was significantly lower than when reared on aphid‐susceptible soybean pods (28 vs. 53%). Development time, adult weight, and proportion females of surviving adults did not differ when reared on Rag1 aphid‐resistant or aphid‐susceptible soybean pods. In choice tests, H. halys exhibited a preference for Rag1 aphid‐resistant over aphid‐susceptible soybean pods after 4 h, but not after 24 h. Halyomorpha halys exhibited no preference when tested with vegetative‐stage or reproductive‐stage soybean plants. The preference by H. halys for Rag1 aphid‐resistant soybean pods and the decreased mortality when reared on these pods suggests that the use of Rag1 aphid‐resistant soybean may favor this emerging pest in the north central USA.
Amylin receptor components and the leptin receptor are co‐expressed in single rat area postrema neurons
Authors: Liberini Claudia G. , Boyle Christina N. , Cifani Carlo , Venniro Marco , Hope Bruce T. , Lutz Thomas A.
Published: January 2016

Amylin is a pancreatic β‐cell hormone that acts as a satiating signal to inhibit food intake by binding to amylin receptors (AMYs) and activating a specific neuronal population in the area postrema (AP). AMYs are heterodimers that include a calcitonin receptor (CTR) subunit [CTR isoform a or b (CTRa or CTRb)] and a member of the receptor activity‐modifying proteins (RAMPs). Here, we used single‐cell quantitative polymerase chain reaction to assess co‐expression of AMY subunits in AP neurons from rats that were injected with amylin or vehicle. Because amylin interacts synergistically with the adipokine leptin to reduce body weight, we also assessed the co‐expression of AMY and the leptin receptor isoform b (LepRb) in amylin‐activated AP neurons. Single cells were collected from Wistar rats and from transgenic Fos‐GFP rats that express green fluorescent protein (GFP) under the control of the Fos promoter. We found that the mRNAs of CTRa, RAMP1, RAMP2 and RAMP3 were all co‐expressed in single AP neurons. Moreover, most of the CTRa+ cells co‐expressed more than one of the RAMPs. Amylin down‐regulated RAMP1 and RAMP3 but not CTR mRNAs in AMY+ neurons, suggesting a possible negative feedback mechanism of amylin at its own primary receptors. Interestingly, amylin up‐regulated RAMP2 mRNA. We also found that a high percentage of single cells that co‐expressed all components of a functional AMY expressed LepRb mRNA. Thus, single AP cells expressed both AMY and LepRb, which formed a population of first‐order neurons that presumably can be directly activated by amylin and, at least in part, also by leptin.
The synthetic progesterone Norgestrel is neuroprotective in stressed photoreceptor‐like cells and retinal explants, mediating its effects via basic fibroblast growth factor, protein kinase A and glycogen synthase kinase 3β signalling
Authors: Wyse Jackson Alice C. , Cotter Thomas G.
Published: January 2016

The synthetic progesterone Norgestrel has been shown to have proven neuroprotective efficacy in two distinct models of retinitis pigmentosa: the rd10/rd10 (B6.CXBI‐Pde6brd10/J) mouse model and the Balb/c light‐damage model. However, the cellular mechanism underlying this neuroprotection is still largely unknown. Therefore, this study aimed to examine the downstream signalling pathways associated with Norgestrel both in vitro and ex vivo. In this work, we identify the potential of Norgestrel to rescue stressed 661W photoreceptor‐like cells and ex vivo retinal explants from cell death over 24 h. Norgestel is thought to work through an upregulation of neuroprotective basic fibroblast growth factor (bFGF). Analysis of 661W cells in vitro by real‐time polymerase chain reaction (rt‐PCR), enzyme‐linked immunosorbent assay (ELISA) and Western blotting revealed an upregulation of bFGF in response to Norgestrel over 6 h. Specific siRNA knockdown of bFGF abrogated the protective properties of Norgestrel on damaged photoreceptors, thus highlighting the crucial importance of bFGF in Norgestrel‐mediated protection. Furthermore, Norgestrel initiated a bFGF‐dependent inactivation of glycogen synthase kinase 3β (GSK3β) through phosphorylation at serine 9. The effects of Norgestrel on GSK3β were dependent on protein kinase A (PKA) pathway activation. Specific inhibition of both the PKA and GSK3β pathways prevented Norgestrel‐mediated neuroprotection of stressed photoreceptor cells in vitro. Involvement of the PKA pathway following Norgestrel treatment was also confirmed ex vivo. Therefore, these results indicate that the protective efficacy of Norgestrel is, at least in part, due to the bFGF‐mediated activation of the PKA pathway, with subsequent inactivation of GSK3β.
Getting back on the beat: links between auditory–motor integration and precise auditory processing at fast time scales
Authors: Tierney Adam , Kraus Nina
Published: January 2016

The auditory system is unique in its ability to precisely detect the timing of perceptual events and use this information to update motor plans, a skill that is crucial for language. However, the characteristics of the auditory system that enable this temporal precision are only beginning to be understood. Previous work has shown that participants who can tap consistently to a metronome have neural responses to sound with greater phase coherence from trial to trial. We hypothesized that this relationship is driven by a link between the updating of motor output by auditory feedback and neural precision. Moreover, we hypothesized that neural phase coherence at both fast time scales (reflecting subcortical processing) and slow time scales (reflecting cortical processing) would be linked to auditory–motor timing integration. To test these hypotheses, we asked participants to synchronize to a pacing stimulus, and then changed either the tempo or the timing of the stimulus to assess whether they could rapidly adapt. Participants who could rapidly and accurately resume synchronization had neural responses to sound with greater phase coherence. However, this precise timing was limited to the time scale of 10 ms (100 Hz) or faster; neural phase coherence at slower time scales was unrelated to performance on this task. Auditory–motor adaptation therefore specifically depends upon consistent auditory processing at fast, but not slow, time scales.
Determinants of local and regional communities in intermittent and perennial headwaters of the Bolivian Amazon
Authors: Datry Thibault , Moya Nabor , Zubieta Jose , Oberdorff Thierry
Published: January 2016

The effect of drying events on aquatic biodiversity is still overlooked in wet Neotropical systems. Yet, the responses of local communities and metacommunities in these biodiversity hotspots may differ from what is reported in other areas.

We addressed the effect of drying events on local and regional fish and macroinvertebrate communities in the headwaters of the Chipiriri River basin, in the wet Neotropical piedmont of Bolivia. According to current knowledge in intermittent rivers and ephemeral streams (IRES) ecology, we predicted that intermittent (INT) sites would harbour lower α‐diversity, but higher β‐diversity, than perennial (PER) sites, due to local, negative effect of drying combined with the existence of multiple recovery stages at the network scale.

Although habitat variables were similar between INT and PER sites, local and regional diversity patterns differed. Local invertebrate communities were not different between site types as soon as 4–6 weeks after flow resumption. The proximity of colonist sources and frequent rainfall probably enhanced persistence through dry periods and high resilience. In contrast, fish communities were still poorer at INT than PER sites, indicating they were still in the process of recolonising upstream INT reaches.

β‐diversity analyses confirmed that invertebrate and fish metacommunities were not at the same recovery stage because (i) β‐diversity of invertebrates was best explained by physical and environmental distances at both INT and PER sites, whereas that of fish was explained only by physical distances at INT sites; (ii) fish β‐diversity was higher at INT than at PER sites, but invertebrate β‐diversity was similar; and (iii) physical distances were correlated with the turnover component of invertebrate β‐diversity but with the nestedness component for fish.

Exploring regional community patterns in IRES and across biota with different dispersal abilities and modes can advance metacommunity theory and improve our ability to predict local community composition in dynamic ecosystems.
Microbial Fe(III) oxide reduction potential in Chocolate Pots hot spring, Yellowstone National Park
Authors: Fortney N. W. , He S. , Converse B. J. , Beard B. L. , Johnson C. M. , Boyd E. S. , Roden E. E.
Published: January 2016

Chocolate Pots hot springs (CP) is a unique, circumneutral pH, iron‐rich, geothermal feature in Yellowstone National Park. Prior research at CP has focused on photosynthetically driven Fe(II) oxidation as a model for mineralization of microbial mats and deposition of Archean banded iron formations. However, geochemical and stable Fe isotopic data have suggested that dissimilatory microbial iron reduction (DIR) may be active within CP deposits. In this study, the potential for microbial reduction of native CP Fe(III) oxides was investigated, using a combination of cultivation dependent and independent approaches, to assess the potential involvement of DIR in Fe redox cycling and associated stable Fe isotope fractionation in the CP hot springs. Endogenous microbial communities were able to reduce native CP Fe(III) oxides, as documented by most probable number enumerations and enrichment culture studies. Enrichment cultures demonstrated sustained DIR driven by oxidation of acetate, lactate, and H2. Inhibitor studies and molecular analyses indicate that sulfate reduction did not contribute to observed rates of DIR in the enrichment cultures through abiotic reaction pathways. Enrichment cultures produced isotopically light Fe(II) during DIR relative to the bulk solid‐phase Fe(III) oxides. Pyrosequencing of 16S rRNA genes from enrichment cultures showed dominant sequences closely affiliated with Geobacter metallireducens, a mesophilic Fe(III) oxide reducer. Shotgun metagenomic analysis of enrichment cultures confirmed the presence of a dominant G. metallireducens‐like population and other less dominant populations from the phylum Ignavibacteriae, which appear to be capable of DIR. Gene (protein) searches revealed the presence of heat‐shock proteins that may be involved in increased thermotolerance in the organisms present in the enrichments as well as porin–cytochrome complexes previously shown to be involved in extracellular electron transport. This analysis offers the first detailed insight into how DIR may impact the Fe geochemistry and isotope composition of a Fe‐rich, circumneutral pH geothermal environment.
An economically based evaluation index for perennial and short‐term ryegrasses in New Zealand dairy farm systems
Authors: Chapman D. F. , Bryant J. R. , Olayemi M. E. , Edwards G. R. , Thorrold B. S. , McMillan W. H. , Kerr G. A. , Judson G. , Cookson T. , Moorhead A. , Norriss M.
Published: January 2016

Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs ($ ha−1 calculated as change in operating profit divided by unit change of the trait) for additional DM produced in different seasons of the year in four regions. The EV of early spring DM was consistently high across all regions, whereas EV for late spring DM was moderate to low. Genotype × environment analysis revealed significant reranking of DM yield among ryegrass cultivars across regions. Hence, separate performance values (PVs) were calculated for two mega‐environments and then combined with the corresponding season and region EV to calculate the overall EV for twenty‐three perennial ryegrass and fifteen short‐term ryegrass cultivars. The difference in operating profit between the highest ranked and lowest ranked perennial ryegrass cultivar ranged from $556 ha−1 to $863 ha−1 year−1 depending on region. For short‐term ryegrasses used for winter feed, the corresponding range was $394 to $478 ha−1 year−1. Using PV for DM yield, it was estimated that plant improvement in perennial ryegrass has added $12–$18 ha−1 year−1 (depending on region) operating profit on dairy farms since the mid‐1960s.
Enhanced Thermoelectric Performance of SmBaCuFeO5+δ/Ag Composite Ceramics
Authors: Zeng Chengcheng , Butt Sajid , Lin Yuan‐Hua , Li Ming , Nan Ce‐Wen
Published: January 2016

Polycrystalline SmBaCuFeO5+δ/Ag composite ceramics have been synthesized by a traditional ceramic processing method. Phase composition and microstructural analyses indicate that with the introduction of Ag additives, the second phases of copper oxides and Ag appear in these composite ceramic samples. The hole concentration and molibility can be enhanced greatly by the addition of Ag particles, which results in a large increase in the electrical conductivity. The thermal conductivity behaviors show that phonons can be scattered effectively by point defects and mesoscale grain boundaries, which remain a slight change in thermal conductivity. A maximum ZT value 0.047 has been achieved at 1023 K in the SmBaCuFeO5+δ/20 vol% Ag composite ceramic, and is about 16 times than the pure SmBaCuFeO5+δ sample. Our results reveal that Ag addition is an effective way to enhance the thermoelectric properties.
A New Alternative for Obtaining Nanocrystalline Bioactive Coatings: Study of Hydroxyapatite Deposition Mechanisms by Cold Gas Spraying
Authors: Cinca Núria , Vilardell Anna M. , Dosta Sergi , Concustell Amadeu , Garcia Cano Irene , Guilemany Josep Maria , Estradé Sonia , Ruiz Alicia , Peiró Francesca
Published: January 2016

The present article is intended to study the deposition mechanisms of bioactive hydroxyapatite (HA) particles by means of Cold Gas Spraying (CGS). A comparison of the deposition on two different substrates (Ti6Al4V and Al7075T6) and different particle sizes is presented. Although this is a more specific deposition technique for ductile materials, it is here shown that, in certain conditions, ceramic deposition is possible despite the inherent low ductility. The resulting internal structure and the features at the particle–substrate interface are discussed in view of Transmission Electron Microscopy examinations of a Focused Ion Beam lift‐out prepared sample. Mainly, under shock compressive loading, the porous sintered powder proceeds through pore collapse, fragmentation and densification as well as grain refinement. The process is described through different plastic mechanisms in ceramics. This opens a new alternative route to produce nanocrystalline HA coatings through a cost‐effective process.
Effect of low‐level laser therapy as an adjuvant in the treatment of periodontitis induced in rats subjected to 5‐fluorouracil chemotherapy
Authors: Theodoro L. H. , Longo M. , Ervolino E. , Duque C. , Ferro‐Alves M. L. , Assem N. Z. , Louzada L. M. , Garcia V. G.
Published: January 2016

Background and Objective

This study aimed to assess the effect of multiple sessions of a low‐level laser therapy (LLLT) adjuvant to scaling and root planing (SRP) on the treatment of experimental periodontitis (EP) in rats treated with 5‐fluorouracil (5‐FU).

Material and Methods

A total of 120 rats were divided into five groups: no treatment (NT); treatment with 5‐FU (60 and 40 mg/kg) and no local periodontal treatment (5FU); treatment with 5‐FU and SRP (5FU‐SRP); treatment with 5‐FU, SRP and one LLLT session (660 nm; 0.035 W; 4.2 J; 120 s) (5FU‐SRP‐1LLLT); and treatment with 5‐FU, SRP and four LLLT sessions (0, 24, 48 and 72 h) (5FU‐SRP‐4LLLT). EP was induced in the mandibular molars through ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. TRAP, proliferating cell nuclear antigen, RANKL, osteoprotegerin and activated caspase‐3 patterns were analysed by immunolabeling. Prostaglandin E2 was quantified using an ELISA, and tumour necrosis factor α and interleukin‐6 were assessed using the multiplex method. The prevalence rates of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum were assessed using the PCR method. The data were subjected to statistical analysis (α = 5%).

Results

5FU, 5FU‐SRP and 5FU‐SRP‐1LLLT treatment groups showed higher ABL compared with the NT group (p < 0.05), whereas the 5FU‐SRP‐4LLLT group showed lower ABL compared with the 5FU group on day 7 and decreased RANKL immunolabeling (p < 0.05).

Conclusion

Treatment with 5‐FU worsened EP, and multiple LLLT sessions adjuvant to SRP seemed to improve periodontitis in rats subjected to 5‐FU chemotherapy.
Physiological responses to extreme hydrological events in the Pantanal wetland: heterogeneity of a plant community containing super‐dominant species
Authors: Dalmagro Higo J. , Lathuillière Michael J. , Vourlitis George L. , Campos Roberto C. , Pinto Osvaldo Borges , Johnson Mark S. , Ortíz Carmen E.R. , Lobo Francisco de A. , Couto Eduardo G.
Published: January 2016

Aims

We tested two mechanisms of adaptation to extreme hydrological stresses (flooding and drought) of species making up a tropical wetland plant community by measuring leaf gas exchange and water potential. We hypothesized that anoxic conditions that occur during flooding will decrease leaf gas exchange when compared to the dry season, and that ‘super‐dominant’ species will have a distinctive physiological advantage when compared to other plants within the community.

Location

Northern Pantanal wetland, Private Natural Heritage Reserve of the Brazilian Social Service of Commerce (RPPN‐SESC Pantanal), Mato Grosso, Brazil.

Methods

Two periods representing typical extreme hydrological conditions in the Pantanal wetland were selected based on historical soil and meteorological measurements: (1) a drought period when plants experience stress due to soil moisture deficits during a dry season that persists for several months (May to Sept), and (2) a flooding period when oxidation‐reduction potential is negative for 30 d or more (Mar or Apr), indicating anoxic stress. Measurements of gas exchange and leaf water potential were made on seven species in drought and flood stress conditions. The seven species represent the majority of the plant community.

Results

As a whole, the plant community showed significantly lower potential net photosynthesis (PN) during flooding when soil oxidation‐reduction potential reached close to −900 mV when compared to the dry season, but the magnitude of the decline in PN was species specific. Not all super‐dominant species showed higher PN compared to non‐dominant species, but they did demonstrate higher stomatal conductance and transpiration leading to lower water use efficiency. The combination of higher PN despite low soil water content suggests that the plant community had access to deep water resources. This access was also confirmed by the midday leaf water potential, which was similar for the flood and dry seasons.

Conclusions

Results suggest that the plant community may have high physiological performance under a wide range of soil oxidation‐reduction potentials. Higher PN rates of super‐dominant species indicate a physiological advantage of these species in the different hydrological conditions.
Provision of specialist‐led minor oral surgery service in Scottish NHS dental practices – analysis of benefits and costs
Authors: Bharadwaj G.V. , Rice M.J.
Published: January 2016

This article evaluates the benefits of specialist‐led minor oral surgery service in Scottish primary care dental practice.

Objectives

The aims of the study were to:

Study practice‐based minor oral surgery service delivery.

Estimate waiting times for these patients.

Explore complications.

Evaluate cost allocated for procedures in minor oral surgery in primary and secondary sector.

Materials and Methods

Retrospective analysis of procedures carried out, waiting times, complications and comparative cost in minor oral surgery from two NHS dental practices located in Lothian health board area.

Results

A total of 1896 procedures in 982 patients having minor oral surgery were analysed across two sites. Of procedures, 51% (971) were simple extractions; 31% (580) of the procedures were surgical removal of non‐third molar teeth; 15% (275) of the procedures were surgical extraction of third molars; and 3% (70) of the procedures were complex procedures such as surgical exposure of canines, removal of simple cysts and closure of oroantral communication. Two hundred and nine procedures were carried out under intravenous sedation. It was difficult to estimate waiting times although all patients were treated within 4 weeks. The overall complication rate was 8.1%. There is a considerable difference in cost allocated to similar procedures in primary and secondary care and the money allocated for carrying out minor oral surgery in primary care is not cost neutral.

Conclusions

It is cost efficient to treat minor oral surgery patients in primary care. Like for like procedures in minor oral surgery are expensive and potentially wait longer before receiving treatment in secondary care.
Self‐initiated actions result in suppressed auditory but amplified visual evoked components in healthy participants
Authors: Mifsud Nathan G. , Oestreich Lena K. L. , Jack Bradley N. , Ford Judith M. , Roach Brian J. , Mathalon Daniel H. , Whitford Thomas J.
Published: January 2016

Self‐suppression refers to the phenomenon that sensations initiated by our own movements are typically less salient, and elicit an attenuated neural response, compared to sensations resulting from changes in the external world. Evidence for self‐suppression is provided by previous ERP studies in the auditory modality, which have found that healthy participants typically exhibit a reduced auditory N1 component when auditory stimuli are self‐initiated as opposed to externally initiated. However, the literature investigating self‐suppression in the visual modality is sparse, with mixed findings and experimental protocols. An EEG study was conducted to expand our understanding of self‐suppression across different sensory modalities. Healthy participants experienced either an auditory (tone) or visual (pattern‐reversal) stimulus following a willed button press (self‐initiated), a random interval (externally initiated, unpredictable onset), or a visual countdown (externally initiated, predictable onset—to match the intrinsic predictability of self‐initiated stimuli), while EEG was continuously recorded. Reduced N1 amplitudes for self‐ versus externally initiated tones indicated that self‐suppression occurred in the auditory domain. In contrast, the visual N145 component was amplified for self‐ versus externally initiated pattern reversals. Externally initiated conditions did not differ as a function of their predictability. These findings highlight a difference in sensory processing of self‐initiated stimuli across modalities, and may have implications for clinical disorders that are ostensibly associated with abnormal self‐suppression.
Differential atrial performance at rest and exercise in athletes: Potential trigger for developing atrial dysfunction?
Authors: Gabrielli L. , Bijnens B. H. , Brambila C. , Duchateau N. , Marin J. , Sitges‐Serra I. , Mont L. , Brugada J. , Sitges M.
Published: January 2016

Highly trained athletes show an increased risk of atrial arrhythmias. Little is known about atrial volumes and function during exercise in this population. Our aim was to analyze atrial size and contractile function during exercise. Fifty endurance athletes with 11 ± 8 h of training per week and 30 sedentary control subjects were included. Echocardiography was performed at baseline and during exercise. Left (LA) and right atrial (RA) size and function were assessed by two‐dimensional echocardiography. Peak negative strain (Sa) during atrial contraction and active atrial emptying volume (AEV) were measured. Athletes and control subjects showed a significant increment of deformation and AEV of both atria with exercise (P < 0.01 vs baseline for LA and RA). Among athletes, a subgroup with significant LA (n = 8)/RA (n = 15) dilatation (≥40 mL/m2) showed a significantly lower increment in AEV with exercise (LA∆AEV: 1.4 ± 1.1 mL/m2 vs 2.1 ± 0.9 mL/m2, P = 0.04; RA∆AEV: 0.9 ± 0.8 mL/m2 vs 2.3 ± 1.1 mL/m2, P < 0.01) and lower increment in deformation vs other athletes (LA∆Sa: −3.2 ± 2.9% vs −9.5 ± 4.4%, P < 0.01; RA∆Sa: −2.5 ± 3.3% vs. −9.8 ± 3.3%, P < 0.01). During exercise, active atrial strain increases, but less in athletes compared to controls, but due to larger atrial volumes, they reached similar increases in atrial emptying volume. However, this overall lesser deformation increases from a subgroup with significant atrial dilatation showing impairment in atrial contractile reserve.
Late aspergilloma of a renal allograft without need for operative management: a case report and review of the literature
Authors: Shannon E.M. , Reid M.J.A. , Chin‐Hong P.
Published: January 2016

Aspergillus infection localized to the renal allograft is a rare and potentially life‐threatening infection and typically requires a combination of operative and medical management. We report the case of a renal allograft aspergilloma in a renal transplant patient presenting 2 years post transplant, successfully managed non‐surgically. To our knowledge, this is the first report of a patient presenting with an allograft aspergilloma so long after transplantation and being successfully managed with antifungal therapy alone.
Phenotyping Rh/Kell and risk of alloimmunization in haematological patients
Authors: Baía F. , Correia F. , Alves B. , Martinez F. , Koch C. , Carneiro A. , Araújo F.
Published: January 2016

Background

One of the biggest concerns in transfusion medicine is to avoid red blood cell alloimmunization. We evaluated the rate of alloimmunization in two groups of chronically transfused patients (A – not phenotyped and B – phenotyped for Rh/K antigens before the first transfusion) with primary haematological disorders and its distribution among the main haematological diseases, in order to adopt an efficient transfusional strategy.

Study design and methods

As methodology, we used the SIBAS and SAM databases for the retrospective study of all patients with primary haematological disorder between January 2011 and April 2013.

Results

A statistical difference in the rate of alloimmunization comparing groups A and B was found (P <0·0001). We also observed that alloimmunization was not homogeneously distributed in all primary haematological diseases.

Conclusions

The Rh/K phenotype should be performed on all patients diagnosed with bone marrow failure, plasma cell dyscrasia and myelodysplastic syndrome in order to avoid alloimmunization. In patients with acute leukaemia and lymphoma it seems not necessary to perform it. In patients with haemoglobinopathy and myeloproliferative disorders, a larger group of patients is needed to decide its efficacy.
Ranavirus in an outbreak of dermatophilosis in captive inland bearded dragons (Pogona vitticeps)
Authors: Tamukai Kenichi , Tokiwa Toshihiro , Kobayashi Hideki , Une Yumi
Published: January 2016

Background

Various pathogens cause skin diseases in lizards. An outbreak of skin disease occurred in a population of 100 inland bearded dragons at a breeding facility in Japan; 50 developed skin lesions and 15 mortalities were reported.

Hypothesis/Objectives

To identify the pathogens responsible for the skin lesions and to determine the cause of death.

Animals

Eight specimens (three dead, two euthanized, three living) were randomly selected from a group of inland bearded dragons with skin lesions consisting of multifocal superficial dermatitis.

Methods

Biopsy samples were taken from skin lesions and healthy skin of the live specimens. Postmortem examinations were performed on the dead and euthanized specimens. Skin samples were processed for microbiological culture, 16S ribosomal DNA (rDNA) sequencing for bacteria, ranavirus major capsid protein (MCP) gene sequencing and histopathological examination. Histopathological examinations were also performed on postmortem tissue samples.

Results

Both Austwickia chelonae and ranavirus (DNA) were detected in the skin lesions. Pathological examination revealed no significant visceral lesions caused by A. chelonae or ranavirus infection in dead specimens.

Conclusions and clinical importance

To the best of the authors’ knowledge this is the first report of dermatophilosis due to A. chelonae infection in lizards and the first description of a concurrent infection with a ranavirus. The combined infection associated with the skin lesions may have been the primary cause of death. Co‐infection with a ranavirus should be considered as a possible factor in cases of reptilian dermatophilosis.
Phylogenetic relationships of Simpsonichthys subgenera (Cyprinodontiformes, Rivulidae), including a proposal for a new genus
Authors: Ponzetto Josi M. , Britzke Ricardo , Nielsen Dalton T. B. , Parise‐Maltempi Patricia P. , Alves Anderson L.
Published: January 2016

The systematic knowledge of Simpsonichthys has changed substantially in recent years, with five subgenera having been elevated to the genus category. In view of these taxonomic changes, the aim of the present study was to identify the phylogenetic relationships among this group in order to test a hypothesis of the division of Simpsonichthys. The ATPase 8 and 6 gene sequences of 53 specimens of Simpsonichthys, Xenurolebias, Ophthalmolebias, Spectrolebias and Hypsolebias genera were assessed. The final topology divided the Simpsonichthys subgenera into five clades: clade I (Hypsolebias antenori group and Ophtalmolebias), clade II (Simpsonichtys and Spectrolebias), clade III (Hypsolebias flammeus and H. magnificus groups), clade IV (H. notatus group) and clade V, which included the Xenurolebias genus as a sister group to all the other Simpsonichthys subgenera. Simpsonichthys, Spectrolebias and Hypsolebias could therefor not be described as monophyletic groups, as has been proposed in some hypotheses. The H. antenori, H. notatus and H. magnificus groups, however, were monophyletic. The molecular results also suggested that H. ocellatus belongs to the Hypsolebias flammeus group. The phylogenetic position of H. fasciatus suggested a new group within Hypsolebias, or possibly even a new genus. The characteristics of the Hypsolebias antenori group and their phylogenetic position suggested that only the species of this group should be included in the Hypsolebias genus. The basal position of the Hypsolebias notatus group and its morphological character may represent a new genus. Although the monophyletism of Simpsonichtys could not be recovered, the branches supported the division of the western and eastern clades, possibly due to allopatric speciation. These facts suggest the division of the genus into at least two major clades. In addition, the study of morphological and molecular data is suggested to obtain a better understanding of such complex organisms, and a major taxonomic review is required.
Entropy Generation Minimization in an Electroosmotic Flow of Non-Newtonian Fluid: Effect of Conjugate Heat Transfer
Authors: Goswami Prakash , Mondal Pranab Kumar , Datta Anubhab , Chakraborty Suman
Published: January 2016

We investigate the entropy generation characteristics of a non-Newtonian fluid in a narrow fluidic channel under electrokinetic forcing, taking the effect of conjugate heat transfer into the analysis. We use power-law model to describe the non-Newtonian fluid rheology, in an effort to capture the essential thermohydrodynamics. We solve the conjugate heat transfer problem in an analytical formalism using the thermal boundary conditions of third kind at the outer surface of the walls. We bring out the alteration in the entropy generation behavior as attributable to the rheology-driven alteration in heat transfer, coupled with nonlinear interactions between viscous dissipation and Joule heating originating from electroosmotic effects. We unveil optimum values of different parameters, including both the geometric as well as thermophysical parameters, which lead to the minimization of the entropy generation rate in the system. We believe that the inferences obtained from the present study may bear far ranging consequences in the design of various cooling and heat removal devices/systems, for potential use in microscale thermal management.
Direct Numerical Simulations of a High-Pressure Turbine Vane
Authors: Wheeler Andrew P. S. , Sandberg Richard D. , Sandham Neil D. , Pichler Richard , Michelassi Vittorio , Laskowski Greg
Published: January 2016

In this paper, we establish a benchmark data set of a generic high-pressure (HP) turbine vane generated by direct numerical simulation (DNS) to resolve fully the flow. The test conditions for this case are a Reynolds number of 0.57 × 106 and an exit Mach number of 0.9, which is representative of a modern transonic HP turbine vane. In this study, we first compare the simulation results with previously published experimental data. We then investigate how turbulence affects the surface flow physics and heat transfer. An analysis of the development of loss through the vane passage is also performed. The results indicate that freestream turbulence tends to induce streaks within the near-wall flow, which augment the surface heat transfer. Turbulent breakdown is observed over the late suction surface, and this occurs via the growth of two-dimensional Kelvin–Helmholtz spanwise roll-ups, which then develop into lambda vortices creating large local peaks in the surface heat transfer. Turbulent dissipation is found to significantly increase losses within the trailing-edge region of the vane.
A Parametric Investigation of a Concentrating Photovoltaic/Thermal System With Spectral Filtering Utilizing a Two-Dimensional Heat Transfer Model
Authors: Brekke Nick , Otanicar Todd , DeJarnette Drew , Hari Parameswar
Published: January 2016

A 2D heat transfer model of a hybrid photovoltaic/thermal (PV/T) system has been created. This paper investigates the impact of ideal filters to best accommodate for a nonuniform PV temperature along the length of the receiver. The proposed configuration consists of a GaAs cell laminated to an aluminum extrusion. The working fluid, a transparent high-temperature heat transfer fluid with suspended nanoparticles, flows through the hollow extrusion where it cools the PV cell before it is redirected in front of the cell acting as an optical filter. The model accounts for PV cell efficiency, temperature, and bandgap dependence, the details often neglected in prior works.
Reduced-Order Modeling of Conjugate Heat Transfer Processes
Authors: Blanc Trevor J. , Jones Matthew R. , Gorrell Steven E.
Published: January 2016

This paper describes the application of reduced-order modeling techniques in the simulation of conjugate heat transfer processes. In a reduced-order model (ROM), the dominate features of a system are represented using a limited number of orthonormal basis vectors, which are extracted from a database containing descriptions of the system. Interpolating methods are then used to calculate expansion coefficients that allow representation of the system as linear combinations of the basis vectors. Evidence of the accuracy and computational savings achieved using the reduced-order modeling technique is presented in order to demonstrate its benefits in simulating conjugate heat transfer processes.
Modeling, Simulation and Experimental Validation of a Servo-Pneumatic Control System With Off-the-Shelf Components
Authors: Riofrío José A. , Woodrow Chad , Mallory Jennifer
Published: January 2016

Industrial applications of servo-pneumatics have seen rapid growth in the past few decades due to the recent availability of sophisticated high-speed proportional valves, particularly in the five-ported, “four-way”, center-closed, bidirectional configuration. This paper offers a simple and effective dynamic model and simulation of a complete servo-pneumatic system using off-the-shelf valves and standard PID control, which remains the industry standard. The model combines piston dynamics, thermodynamics of the working fluid (air), mass-flow inlet and exhaust dynamics through the valve, valve dynamics, and a control system. The simulation results are experimentally validated through various closed-loop position control arrangements. The simulation model parameters are for the most part easily measurable, except for the damping coefficient of the moving mass and the discharge coefficient of the valve. A simple approach to effectively estimating each of these is shown. An experimental setup was built using off-the-shelf components: Bimba standard round-line air cylinders, Enfield Technologies high-speed proportional valves, Balluff non-contact magnetostrictive displacement transducer, and pressure sensors from Omegadyne. It is intended that this work can be easily recreated by industrial and academic designers who are considering servo-pneumatic systems.
Experimental Investigation of Air Bubble Behaviour in Stagnant Mineral Oils
Authors: Longhitano Marco , Murrenhoff Hubertus
Published: January 2016

Air contamination in hydraulic fluids strongly affects the performance of fluid power systems. It can cause various problems such as component damage, fluid degradation, noise production and poor system response. In recent years, in order to improve the design of hydraulic systems, multiphase CFD models have been discussed in the literature. These include Euler-Euler and Euler-Lagrangian approaches. They are based on a set of empirical correlations, which describe the air behaviour in a liquid. These empirical parameters are unknown for hydraulic fluids. In this paper, an experimental study of the air bubble behaviour in different stagnant mineral oils is presented, providing knowledge of those parameters. A test apparatus using an optical method developed at the Institute for Fluid Power Drives and Controls of RWTH Aachen University is described. After performing the experiments, the terminal velocity is shown with dependence of the bubble diameter. Theoretical correlations for the drag coefficient are assessed with experimental results and new ones are formulated. Additionally, experiments on bubble coalescence have been performed in terms of bubble equivalent radius and drainage time. The minimum bubble diameter above which the coalescence occurs is indicated as well as the measured velocity and diameter after the coalescence. The drainage time measurements are compared with different theoretical correlations for coalescence. Of these, the most suitable and promising ones for hydraulic oils are selected. The current study is a significant step forward in fluid power modeling, as it provides a reliable framework for multiphase CFD modelling.
Acoustical Simulation of a Hydraulic Swash Plate Motor
Authors: Schleihs Christian , Murrenhoff Hubertus
Published: January 2016

During the past decade tightened safety and health regulations concerning noise pollution in the work place have led to an increased importance of acoustic emissions in machinery. In the course of widespread R&D efforts internal combustion engines have received much attention, leading to their optimization and therefore to a higher contribution of hydraulic components, especially pumps and motors, to the overall machinery sound level.

However, hydraulic industrial design engineering has only recently begun to take acoustic issues into account at an early design stage. This may be due to the situation that the simulation of sound radiation of complex (hydraulic) machinery is not yet as far developed as other finite element analysis (FEA) fields.

In order to improve the sound emission of a variable displacement hydraulic swash plate motor, this paper deals with its acoustic simulation. Therefore an acoustic FEA model is presented. This paper mainly addresses the simulation model setup, the derivation of the resulting dynamic loads and the acoustic analysis, which includes the calculation of the surrounding acoustical near and far field. The simulated sound pressure levels are compared with experimental sound measurements conducted on the motor. Additionally, the influence of different valve plate designs is analyzed.
Variable Displacement Gear and Gerotor Pumps
Authors: Avery Nicholas , Johnston Nigel
Published: January 2016

Three concepts for variable displacement gear and gerotor pumps were proposed. CAD models and physical prototypes were built for demonstrating and understanding the concepts. One concept was taken to the stage of a working prototype. This was constructed using commonly available rapid prototyping techniques. Though it was a crude prototype, the device was found to be able to pump effectively, and the flow varied as expected when the displacement was varied.

The proposed concepts may be suitable for mass market applications such as automotive power steering and engine lubrication, and could provide very significant energy savings.