bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous regulation of F5H in COMT‐RNAi transgenic switchgrass alters effects of COMT suppression on syringyl lignin biosynthesis
Authors: Wu Zhenying , Wang Nengfei , Hisano Hiroshi , Cao Yingping , Wu Fengyan , Liu Wenwen , Bao Yan , Wang Zeng‐Yu , Fu Chunxiang
Published: September 2018

Ferulate 5‐hydroxylase (F5H) catalyses the hydroxylation of coniferyl alcohol and coniferaldehyde for the biosynthesis of syringyl (S) lignin in angiosperms. However, the coordinated effects of F5H with caffeic acid O‐methyltransferase (COMT) on the metabolic flux towards S units are largely unknown. We concomitantly regulated F5H expression in COMT‐down‐regulated transgenic switchgrass (Panicum virgatum L.) lines and studied the coordination of F5H and COMT in lignin biosynthesis. Down‐regulation of F5H in COMT‐RNAi transgenic switchgrass plants further impeded S lignin biosynthesis and, consequently, increased guaiacyl (G) units and reduced 5‐OH G units. Conversely, overexpression of F5H in COMT‐RNAi transgenic plants reduced G units and increased 5‐OH units, whereas the deficiency of S lignin biosynthesis was partially compensated or fully restored, depending on the extent of COMT down‐regulation in switchgrass. Moreover, simultaneous regulation of F5H and COMT expression had different effects on cell wall digestibility of switchgrass without biomass loss. Our results indicate that up‐regulation and down‐regulation of F5H expression, respectively, have antagonistic and synergistic effects on the reduction in S lignin resulting from COMT suppression. The coordinated effects between lignin genes should be taken into account in future studies aimed at cell wall bioengineering.
The impact of positive antinuclear antibody on narrowband ultraviolet B phototherapy in patients with vitiligo: A retrospective chart review
Authors: Nahhas Amanda F. , Nartker Nathan T. , Braunberger Taylor L. , Jacobsen Gordon , Hamzavi Iltefat H.
Published: September 2018

Background/Purpose

Screening antinuclear antibody (ANA) is not recommended prior to initiating narrowband ultraviolet B (NBUVB) phototherapy in vitiligo patients, unless concern for photosensitivity exists. Guidelines on prescribing NBUVB phototherapy in vitiligo patients with positive ANA are unavailable, prompting this study to uncover trends.

Methods

This retrospective chart review investigated patients 12 years of age or older with a diagnosis of vitiligo between January 2015 and September 2017, positive serum ANA, and NBUVB phototherapy. Demographic information, vitiligo type, ANA titer/pattern, starting dose, peak dose without phototoxicity, phototherapy frequency, total number of phototoxic events and treatments, coexisting photosensitizing disorders, and concomitant photosensitizing medications were collected.

Results

Seven (two males, five females) of 1485 charts met inclusion criteria. One Caucasian, two African‐Americans, one Asian, and three Hispanic/Latinos patients were represented. Six of seven patients had generalized vitiligo and one had focal vitiligo. ANA titer/patterns and phototherapy frequencies were evaluated. Peak doses of NBUVB without phototoxic event were available in six of seven patients: 274, 290, 532, 618, 700, and 734 mJ/cm2. Total number of phototoxic events varied: 1 (n = 1), 2 (n = 1), 4 (n = 1), 6 (n = 2), or 8 (n = 1). Total NBUVB treatments ranged between 6 and 132. Coexisting photosensitizing disorders were not identified. One patient had phototoxic events in association with photosensitizing medications.

Conclusion

With regard to phototoxicity, meaningful trends were not identified that may guide prescription of phototherapy in vitiligo patients with positive ANA, suggesting ANA may not be exclusionary criteria when prescribing NBUVB.
Evaluation of a bovine visual pregnancy test for the detection of pregnancy‐associated glycoproteins in sheep
Authors: Steckeler Patricia , Weber Frank , Zerbe Holm , Rieger Anna , Voigt Katja
Published: September 2018

Contents

As sheep produce similar pregnancy‐associated glycoproteins (PAGs) to cattle, a commercially available bovine visual pregnancy test based on the detection of PAGs (visual‐PAG‐test) was evaluated in sheep. The test was performed with whole blood (WhB), plasma (P) and serum (S) of 163 pregnant and 153 non‐pregnant ewes. Additionally, 11 pregnant ewes were tested weekly from day 14 to 49 of gestation and monthly from day 60 to day 149. Ten ewes were sampled weekly from the date of lambing until day 63 post‐partum (p.p.). The sensitivity in mid‐pregnancy (n = 163) was 98.16% (WhB), 99.39% (P) and 99.39% (S) compared to transabdominal ultrasonography as the gold standard while the specificity (n = 153) was 94.12% (WhB), 76.47% (P) and 93.46% (S), respectively. During early pregnancy, all 11 ewes were correctly identified as pregnant on day 42 (100%); however, the test sensitivity decreased to 54.6% (WhB) and 63.6% (S and P, respectively) at day 49. The ewes were again consistently identified as pregnant on day 63 (P) or on day 119 (S, WhB). The test was consistently negative from day 42 p.p. onwards in eight out of ten ewes. Two ewes remained consistently positive until the last sample on day 63 p.p. In conclusion, the test could be used to accurately select pregnant ewes at day 42 with a drop in sensitivity at day 49. The sensitivity of the visual‐PAG‐test was good in mid to late pregnancy, and early detection of pregnancy was possible in individual animals. In some ewes, the PAGs were however detectable for more than 63 days p.p.—the previous breeding history should therefore always be taken into account for correct interpretation of the test results.
Why has Income Inequality in Germany Increased From 2002 to 2011? A Behavioral Microsimulation Decomposition
Authors: Jessen Robin
Published: October 2018

This paper proposes a method to decompose changes in income inequality into the contributions of policy changes, wage rate changes, and population changes while considering labor supply reactions. Using data from the Socio‐Economic Panel (SOEP), this method is applied to decompose the increase in income inequality in Germany from 2002 to 2011, a period that saw tax reductions and a controversial overhaul of the transfer system. The simulations show that tax and transfer reforms have had an inequality‐reducing effect as measured by the mean log deviation and the Gini coefficient. For the Gini, these effects are offset by labor supply reactions. In contrast, policy changes explain part of the increase in the ratio between the 90th and the 50th income percentiles. Changes in wage rates have led to a decrease in income inequality. Thus, the increase in inequality was due to changes in the population.
Carbon stocks in biomass and soils of woody species fodder banks in the dry tropics of Mexico
Authors: Casanova‐Lugo F. , Petit‐Aldana J. , Solorio‐Sánchez F. , Ramírez‐Avilés L. , Ward S. E. , Villanueva‐López G. , Aryal D. R.
Published: September 2018

Understanding carbon (C) dynamics of the silvopastoral systems can help mitigate greenhouse gas emissions. The aim of this study was to evaluate the C concentration and storage in above‐ and belowground tree biomass as well as in the soils of fodder banks of Leucaena leucocephala (Lam.) de Wit, Guazuma ulmifolia (Lam.) or a combination of the both species. The above‐ and belowground biomass was quantified by the destructive sampling. We also obtained samples from soil pits, 20‐cm deep, and determined bulk density and organic carbon concentration. The mixed species banks produced more foliage dry matter (DM) (6.3 t DM/ha) than the pure fodder banks. The total living biomass stocks ranged from 31.5 to 33.5 t DM/ha and did not differ between fodder bank types. The tissue C concentration was greater in stems (45.1%) and roots (44.9%) compared to the foliage component (43.4%). Total soil carbon (TSC) in the 5–10 cm layer was greater in the fodder banks with legumes alone than in mixed species banks (35.7 vs. 30.8 t C/ha). TSC storage in the 15–20 cm layer was greater in the nonlegume fodder bank than in the legume fodder bank (39.8 vs. 34.5 t C/ha). However, to the 0–20 cm layer, TSC was similar for all fodder banks. Thus, the three types of fodder banks had similar total C storage in plant biomass and soil, but the production of foliage biomass was higher in the mixed species banks.
Improved flow cytometry crossmatching in kidney transplantation
Authors: Guillaume Nicolas
Published: October 2018

Flow cytometry crossmatching (FC‐XM) assay is the most sensitive cell‐based method for detecting donor‐specific antibodies (DSAs). However, the use of FC‐XM remains limited by methodological and clinical variations. This basic assay cannot discriminate between complement‐fixing and noncomplement‐fixing antibodies. FC‐XM also detects patient all antibodies bound to donor cells and not only DSAs against to HLA molecules. Pretest factors associated with a donor's medical care can affect test results by changing the number, viability and target on lymphocytes (such as rituximab on CD20+ B‐cells). Assay adjustment can be performed to improve the sensitivity and specificity of FC‐XM. Pronase treatment (0.5‐1 mg/mL) prevents false‐positive B‐cell FC‐XM due to nonspecific immunoglobulin binding by Fc receptors and binding of surface immunoglobulins onto the surface of B‐cells. Pronase treatment (2 mg/mL) or a serum incubation step with an anti‐rituximab monoclonal antibody (Ab) prevents the interference induced by rituximab therapy. The use of 7 aminoactinomycin‐D (7‐AAD) or fluorochrome‐conjugated C4d Ab, after complement incubation, allows complement‐fixing antibodies to be distinguished from noncomplement‐fixing antibodies. The use of donor endothelial precursor cells as target cells allows the detection of nonmajor histocompatibility complex Ab‐binding endothelial cells. However, lymphocyte crossmatches still had some limits in specificity and sensitivity. This implies that this assay must be interpreted with the virtual crossmatch.
Apheresis causes complement deposition on red blood cells (RBCs) and RBC antigen alterations, possibly inducing enhanced clearance
Authors: de Back Djuna Z. , Nezjad Shahryar G. , Beuger Boukje M. , Veldhuis Martijn , Clifford Els , Ait Ichou Fatima , Berghuis Jeffrey , Go Mya , Gouwerok Eric , Meinderts Sanne , Vrielink Hans , de Kort Wim , de Korte Dirk , van Kraaij Marian , van Bruggen Robin
Published: September 2018

BACKGROUND

Apheresis is increasingly being applied to collect cells or plasma, even allowing the collection of multiple blood components during one procedure. Although the quality of the cellular and plasma products that are obtained by apheresis have been extensively studied and shown to be of high quality, the impact of apheresis on the red blood cells (RBCs) that are returned to the donor has not been investigated.

STUDY DESIGN AND METHODS

The effect of the plasma‐ or plateletpheresis procedures by four different devices—MCS+ (Haemonetics), PCS2 (Haemonetics), Trima Accel (Terumo BCT), and Autopheresis‐C (Auto‐C, Fresenius Kabi)—on the RBCs that are returned to the donor was tested in a blinded, prospective trial in a cohort of 25 donors.

RESULTS

A rheologic analysis of donor RBCs before and after plasma‐ or plateletpheresis showed no differences in outcome. However, a strong increase in hemolysis was found in samples from the Trima Accel devices after plateletpheresis, compared to all other machines tested. Furthermore, an increase in complement deposition on RBCs was seen after all plasmapheresis procedures (MCS+, PCS2, and Auto‐C). Finally, a significant decrease in the expression of the complement‐regulating protein CD59 was seen in all postapheresis samples as well as a significant decrease of the adhesion molecule CD147.

CONCLUSION

The increase in complement deposition and the decrease in the expression of CD59 suggests that RBC clearance might be enhanced after return to the donor. Possible side effects due to an increase in hemolysis after Trima Accel plateletpheresis should be further investigated.
Effects of red blood cell (RBC) transfusion on sickle cell disease recipient plasma and RBC metabolism
Authors: Culp‐Hill Rachel , Srinivasan Amudan J. , Gehrke Sarah , Kamyszek Reed , Ansari Andrea , Shah Nirmish , Welsby Ian , D'Alessandro Angelo
Published: September 2018

BACKGROUND

Exchange transfusion is a mainstay in the treatment of sickle cell anemia. Transfusion recipients with sickle cell disease (SCD) can be transfused over 10 units per therapy, an intervention that replaces circulating sickle red blood cells (RBCs) with donor RBCs. Storage of RBCs makes the intervention logistically feasible. The average storage duration for units transfused at the Duke University Medical Center is approximately 2 weeks, a time window that should anticipate the accumulation of irreversible storage lesion to the RBCs. However, no metabolomics study has been performed to date to investigate the impact of exchange transfusion on recipients' plasma and RBC phenotypes.

STUDY DESIGN AND METHODS

Plasma and RBCs were collected from patients with sickle cell anemia before transfusion and within 5 hours after exchange transfusion with up to 11 units, prior to metabolomics analyses.

RESULTS

Exchange transfusion significantly decreased plasma levels of markers of systemic hypoxemia like lactate, succinate, sphingosine 1‐phosphate, and 2‐hydroxyglutarate. These metabolites accumulated in transfused RBCs, suggesting that RBCs may act as scavenger/reservoirs. Transfused RBCs displayed higher glycolysis, total adenylate pools, and 2,3‐diphosphoglycerate, consistent with increased capacity to deliver oxygen. Plasma levels of acyl‐carnitines and amino acids decreased, while fatty acids and potentially harmful phthalates increased upon exchange transfusion.

CONCLUSION

Metabolic phenotypes confirm the benefits of the transfusion therapy in transfusion recipients with SCD and the reversibility of some of the metabolic storage lesion upon transfusion in vivo in 2‐week‐old RBCs. However, results also suggest that potentially harmful plasticizers are transfused.
Ultraviolet C light efficiently inactivates nonenveloped hepatitis A virus and feline calicivirus in platelet concentrates
Authors: Gravemann Ute , Handke Wiebke , Lambrecht Bernd , Schmidt Jörg‐Peter , Müller Thomas H. , Seltsam Axel
Published: September 2018

BACKGROUND

Nonenveloped transfusion‐transmissible viruses such as hepatitis A virus (HAV) and hepatitis E virus (HEV) are resistant to many of the common virus inactivation procedures for blood products. This study investigated the pathogen inactivation (PI) efficacy of the THERAFLEX UV‐Platelets system against two nonenveloped viruses: HAV and feline calicivirus (FCV), in platelet concentrates (PCs).

STUDY DESIGN AND METHODS

PCs in additive solution were spiked with high titers of cell culture–derived HAV and FCV, and treated with ultraviolet C at various doses. Pre‐ and posttreatment samples were taken and the level of viral infectivity determined at each dose. For some samples, large‐volume plating was performed to improve the detection limit of the virus assay.

RESULTS

THERAFLEX UV‐Platelets reduced HAV titers in PCs to the limit of detection, resulting in a virus reduction factor of greater than 4.2 log steps, and reduced FCV infectivity in PCs by 3.0 ± 0.2 log steps.

CONCLUSIONS

THERAFLEX UV‐Platelets effectively inactivates HAV and FCV in platelet units.
Assessment of HIV transfusion transmission risk in South Africa: a 10‐year analysis following implementation of individual donation nucleic acid amplification technology testing and donor demographics eligibility changes
Authors: Vermeulen Marion , Lelie Nico , Coleman Charl , Sykes Wendy , Jacobs Genevieve , Swanevelder Ronel , Busch Michael , van Zyl Gert , Grebe Eduard , Welte Alex , Reddy Ravi
Published: September 2018

BACKGROUND

In 1998 we estimated that 34/million infectious window period donations were entering the blood supply at the South African National Blood Service. Selective use of donations based on donor race‐ethnicity reduced this risk to 26/million donations but was deemed unethical. Consequently, in 2005 South African National Blood Service eliminated race‐ethnicity–based collection policies and implemented individual‐donation nucleic acid testing (ID‐NAT). We describe the change in donor base demographics, human immunodeficiency virus (HIV) detection rates, and transfusion‐transmissible HIV risk.

STUDY DESIGN AND METHODS

In ten years 7.7 million donations were tested for anti‐HIV and HIV RNA. Number of donations, HIV prevalence, ID‐NAT yield rate, serology yield rate and residual transfusion‐transmissible HIV risk were analyzed by donor type, race‐ethnicity, age, and sex. Multiple regression analysis was performed to investigate the determinants of HIV‐positive and nucleic acid testing yield donations.

RESULTS

The combined strategy of increasing donations from black donors and implementing ID‐NAT increased the proportion of donations from black donors from 6% in 2005 to 30% in 2015 (p < 0.00001), and reduced the transfusion‐transmissible risk from 24 to 13 per million transfusions. ID‐NAT interdicted 481 (1:16,100) seronegative window period donations, while one transfusion‐transmissible case (0.13 per million) was documented. Race‐ethnicity and donor type were highly significant predictors of HIV positivity, with adjusted odds ratio for first‐time donors of 12.5 (95% confidence interval, 11.9‐13.1) and for black race‐ethnicity of 31.1 (95% confidence interval, 28.9‐33.4). The proportion of serology yields among HIV‐infected donors increased from 0.27% to 2.4%.

CONCLUSION

ID‐NAT enabled the South African National Blood Service to increase the number of donations from black donors fivefold while enhancing the safety of the blood supply.
Blood, sweat, and tears: Red Blood Cell‐Omics study objectives, design, and recruitment activities
Authors: Endres‐Dighe Stacy M. , Guo Yuelong , Kanias Tamir , Lanteri Marion , Stone Mars , Spencer Bryan , Cable Ritchard G. , Kiss Joseph E. , Kleinman Steve , Gladwin Mark T. , Brambilla Donald J. , D'Andrea Pam , Triulzi Darrell J. , Mast Alan E. , Page Grier P. , Busch Michael P. ,   for the NHLBI Recipient Epidemiology Donor Evaluation Study (REDS)‐III Program
Published: September 2018

BACKGROUND

The Red Blood Cell (RBC)‐Omics study was initiated to build a large data set containing behavioral, genetic, and biochemical characteristics of blood donors with linkage to outcomes of the patients transfused with their donated RBCs.

STUDY DESIGN AND METHODS

The cohort was recruited from four US blood centers. Demographic and donation data were obtained from center records. A questionnaire to assess pica, restless leg syndrome, iron supplementation, hormone use, and menstrual and pregnancy history was completed at enrollment. Blood was obtained for a complete blood count, DNA, and ferritin testing. A leukocyte‐reduced RBC sample was transferred to a custom storage bag for hemolysis testing at Storage Days 39 to 42. A subset was recalled to evaluate the kinetics and stability of hemolysis measures.

RESULTS

A total of 13,403 racially/ethnically diverse (12% African American, 12% Asian, 8% Hispanic, 64% white, and 5% multiracial/other) donors of both sexes were enrolled and ranged from 18 to 90 years of age; 15% were high‐intensity donors (nine or more donations in the prior 24 mo without low hemoglobin deferral). Data elements are available for 97% to 99% of the cohort.

CONCLUSIONS

The cohort provides demographic, behavioral, biochemical, and genetic data for a broad range of blood donor studies related to iron metabolism, adverse consequences of iron deficiency, and differential hemolysis (including oxidative and osmotic stress perturbations) during RBC storage. Linkage to recipient outcomes may permit analysis of how donor characteristics affect transfusion efficacy. Repository DNA, plasma, and RBC samples should expand the usefulness of the current data set.
Surgical management of postcastration spermatic cord stump infection in horses: A retrospective study of 23 cases
Authors: Claffey Elaine F. , Brust Katherine , Hackett Richard P. , Fubini Susan
Published: September 2018

Objective

To report the surgical management and the short‐ and long‐term follow‐up of postcastration spermatic cord infection in horses.

Study design

Retrospective case series.

Animals

Twenty‐three client‐owned horses.

Methods

Medical records (2001‐2017) of horses that had been surgically treated for spermatic cord stump infection after castration were reviewed. Time from castration to presentation, diagnostic procedures, surgical complications, bacterial culture and ancillary testing, and survival to discharge were collected. Long‐term follow‐up was obtained by owner survey when possible. Descriptive statistics were used to report results.

Results

Horses ranged in age from 2 to 14 years (mean age 4.1) and presented 33 days (median; range, 12‐3561) after castration. Five of 23 horses required revision surgery because of hemorrhage (2) or persistent infection (3). All horses survived to discharge. Long‐term follow up was available for 16 horses at a mean time of 27.4 months postsurgery (range 6‐135). Complete resolution of clinical signs and return to previous use was documented in 14 of 16 horses; 1 horse had persistent purulent drainage and a second horse was retired because he did not return to adequate performance.

Conclusion

Postcastration infection of the spermatic cord had a favorable prognosis for short‐ and long‐term survival in this population, although complications included postoperative hemorrhage and persistent infection.

Clinical significance

This study describes the treatment of postcastration infection of the spermatic cord which results in a good survival rate.
Optimization of phenol removal from wastewater by activation of persulfate and ultrasonic waves in the presence of biochar catalyst modified by lanthanum chloride
Authors: Razmi Rasool , Ardjmand Mehdi , Ramavandi Bahman , Heydarinasab Amir
Published: October 2018

In this paper, the effects of phenol concentration, pH, catalyst dose, persulfate concentration, temperature and contact time on the phenol removal from wastewater by activation of persulfate (S2O8−2) in the presence of biochar modified by lanthanum chloride and ultrasonic waves (US) are optimized. Experimental design and optimization were carried out by response surface methodology. The optimum conditions for the maximum phenol removal were obtained pH of 4, phenol concentration of 86 mg/L, catalyst dose of 43 mg/L, persulfate concentration of 86 mg/L, temperature of 41 °C and contact time of 63 min. The optimum phenol removal from synthetic wastewater was attained 97.68%. Phenol removal by the mentioned system was fitted with the first‐order kinetic model. The combination of the ingredients of ‘S2O8−2/US/Biochar‐LaCl3’ system had a synergistic effect on the phenol removal.
Twisting and Tilting Rotors for High-Efficiency, Thrust-Vectored Quadrotors
Authors: Gerber Matthew J. , Tsao Tsu-Chin
Published: October 2018

A mechanism consisting of twisting and tilting joints is introduced to provide omnidirectional thrust-vectoring capabilities to a quadrotor system. This mechanism eliminates mechanical constraints and kinematic singularities to provide full directional authority to all four individual thrust vectors. The presented system fully decouples position and attitude dynamics to overcome the intrinsic maneuverability limitations of traditional multirotors while maximizing thrust efficiency over its entire configuration space. This paper presents a mathematical model of the system, introduces a control method for position and attitude tracking, and presents numerical simulation results that demonstrate the system benefits.
Investigating the Effect of Utilizing New Induction Manifold Designs on the Combustion Characteristics and Emissions of a Direct Injection Diesel Engine
Authors: Bassiony Mohamed A. , Sadiq Abdellatif M. , Gergawy Mohammed T. , Ahmed Samer F. , Ghani Saud A.
Published: September 2018

New induction manifold designs have been developed in this work to enhance the turbulence intensity and improve the mixing quality inside diesel engine cylinders. These new designs employ a spiral-helical shape with three different helical diameters (1D, 2D, 3D; where D is the inner diameter of the manifold) and three port outlet angles: 0 deg, 30 deg, and 60 deg. The new manifolds have been manufactured using three-dimensional printing technique. Computational fluid dynamics simulations have been conducted to estimate the turbulent kinetic energy (TKE) and the induction swirl generated by these new designs. The combustion characteristics that include the maximum pressure raise rate (dP/dθ) and the peak pressure inside the cylinder have been measured for a direct injection (DI) diesel engine utilizing these new manifold designs. In addition, engine performance and emissions have also been evaluated and compared with those of the normal manifold of the engine. It was found that the new manifolds with 1D helical diameter produce a high TKE and a reasonably strong induction swirl, while the ones with 2D and 3D generate lower TKEs and higher induction swirls than those of 1D. Therefore, dP/dθ and peak pressure were the highest with manifolds 1D, in particular manifold m (D, 30). Moreover, this manifold has provided the lowest fuel consumption with the engine load by about 28% reduction in comparison with the normal manifold. For engine emissions, m (D, 30) manifold has generated the lowest CO, SO2, and smoke emissions compared with the normal and other new manifolds as well, while the NO emission was the highest with this manifold.
Dislocation Formation From a Polycrystal Free-Surface
Authors: Colin Jérôme
Published: September 2018

The introduction of a dislocation from the free-surface of a grain A of a polycrystal has been investigated from the theoretical point of view. Assuming two disclination dipoles are lying in a high angle boundary separating the corresponding grain A and a neighbor grain B, the equilibrium position of the dislocation has been determined in the grain A versus the separation distance between the two dipoles, the length and strength of each dipole.
Adiabatic Effectiveness on High-Pressure Turbine Nozzle Guide Vanes Under Realistic Swirling Conditions
Authors: Bacci Tommaso , Becchi Riccardo , Picchi Alessio , Facchini Bruno
Published: September 2018

In modern lean-burn aero-engine combustors, highly swirling flow structures are adopted to control the fuel-air mixing and to provide the correct flame stabilization mechanisms. Aggressive swirl fields and high turbulence intensities are hence expected in the combustor-turbine interface. Moreover, to maximize the engine cycle efficiency, an accurate design of the high-pressure nozzle cooling system must be pursued: in a film-cooled nozzle, the air taken from last compressor stages is ejected through discrete holes drilled on vane surfaces to provide a cold layer between hot gases and turbine components. In this context, the interactions between the swirling combustor outflow and the vane film cooling flows play a major role in the definition of a well-performing cooling scheme, demanding for experimental campaigns at representative flow conditions. An annular three-sector combustor simulator with fully cooled high-pressure vanes has been designed and installed at THT Lab of University of Florence. The test rig is equipped with three axial swirlers, effusion-cooled liners, and six film-cooled high-pressure vanes passages, for a vortex-to-vane count ratio of 1:2. The relative clocking position between swirlers and vanes has been chosen in order to have the leading edge of the central airfoil aligned with the central swirler. In this experimental work, adiabatic film effectiveness measurements have been carried out in the central sector vanes, in order to characterize the film-cooling performance under swirling inflow conditions. The pressure-sensitive paint (PSP) technique, based on heat and mass transfer analogy, has been exploited to catch highly detailed 2D distributions. Carbon dioxide has been used as coolant in order to reach a coolant-to-mainstream density ratio of 1.5. Turbulence and five-hole probe measurements at inlet/outlet of the cascade have been carried out as well, in order to highlight the characteristics of the flow field passing through the cascade and to provide precise boundary conditions. Results have shown a relevant effect of the swirling mainflow on the film cooling behavior. Differences have been found between the central airfoil and the adjacent ones, both in terms of leading edge stagnation point position and of pressure and suction side film coverage characteristics.
The Role of Forcing and Eddy Viscosity Variation on the Log-Layer Mismatch Observed in Wall-Modeled Large-Eddy Simulations
Authors: DeLeon Rey , Senocak Inanc
Published: September 2018

We investigate the role of eddy viscosity variation and the effect of zonal enforcement of the mass flow rate on the log-layer mismatch problem observed in turbulent channel flows. An analysis of the mean momentum balance shows that it lacks a degree-of-freedom (DOF) when eddy viscosity is large, and the mean velocity conforms to an incorrect profile. Zonal enforcement of the target flow rate introduces an additional degree-of-freedom to the mean momentum balance, similar to an external stochastic forcing term, leading to a significant reduction in the log-layer mismatch. We simulate turbulent channel flows at friction Reynolds numbers of 2000 and 5200 on coarse meshes that do not resolve the viscous sublayer. The second-order turbulence statistics agree well with the direct numerical simulation benchmark data when results are normalized by the velocity scale extracted from the filtered velocity field. Zonal enforcement of the flow rate also led to significant improvements in skin friction coefficients.
Study of Crack Initiation of 15-15Ti Austenitic Steel in Liquid PbBi
Authors: Hojna Anna , Di Gabriele Fosca , Chocholousek Michal , Spirit Zbynek , Rozumova Lucia
Published: September 2018

The austenitic steel 15-15Ti is being considered as one of the candidate materials for internal structural components of future heavy liquid metal (HLM) nuclear systems. This work studies the steel compatibility with liquid PbBi. Constant extension rate tensile (CERT) tests of tapered specimens were used to study sensitivity to liquid metal embrittlement (LME) and crack initiation. The taper creates a variation of stress along the gauge length which allows the identification of the stress and strain for the crack appearance. Testing was performed in air and in PbBi with 10−6 to 10−12 wt  % oxygen content at 300 °C. Post-test observation by scanning electron microscopy (SEM) highlighted the crack morphology. An evaluation of the environmental effect on the crack initiation is presented.
Linear Sensor Arrangement for Softwood Grain Angle Measurements by Directional Reflection
Authors: Pan Q. , Schajer G. S.
Published: September 2018

A linear sensor arrangement is presented as a means of measuring the three-dimensional grain angle of wood. The measurement principle is based on an optical characteristic of a wood surface where the microscopic cell structure causes preferential reflection of light perpendicular to the wood grain. This response is notable among the several other techniques for measuring wood grain angle in that it enables identification of diving (out-of-plane) angle in addition to the surface (within-plane) angle. The basic measurement principle has been previously investigated using a circular array of light sensors to measure the spatial distribution of the light reflected from a wood surface. That procedure works reasonably well for surface points near the center of the circle and for modest dive angles. The linear sensor arrangement investigated here is designed to extend measurement functionality so as to be able to measure grain angle at any point along a central line and over a greater range of dive angle. A prototype scanner system is presented together with example experimental results for clear wood samples and for a face knot sample.
Pressurized Infusion: A New and Improved Liquid Composite Molding Process
Authors: Akif Yalcinkaya M. , Guloglu Gorkem E. , Pishvar Maya , Amirkhosravi Mehrad , Murat Sozer E. , Cengiz Altan M.
Published: September 2018

Vacuum-assisted resin transfer molding (VARTM) has several inherent shortcomings such as long mold filling times, low fiber volume fraction, and high void content in fabricated laminates. These problems in VARTM mainly arise from the limited compaction of the laminate and low resin pressure. Pressurized infusion (PI) molding introduced in this paper overcomes these disadvantages by (i) applying high compaction pressure on the laminate by an external pressure chamber placed on the mold and (ii) increasing the resin pressure by pressurizing the inlet resin reservoir. The effectiveness of PI molding was verified by fabricating composite laminates at various levels of chamber and inlet pressures and investigating the effect of these parameters on the fill time, fiber volume fraction, and void content. Furthermore, spatial distribution of voids was characterized by employing a unique method, which uses a flatbed scanner to capture the high-resolution planar scan of the fabricated laminates. The results revealed that PI molding reduced fill time by 45%, increased fiber volume fraction by 16%, reduced void content by 98%, improved short beam shear (SBS) strength by 14%, and yielded uniform spatial distribution of voids compared to those obtained by conventional VARTM.
Quantifying the Resilience-Informed Scenario Cost Sum: A Value-Driven Design Approach for Functional Hazard Assessment
Authors: Hulse Daniel , Hoyle Christopher , Goebel Kai , Tumer Irem Y.
Published: September 2018

Complex engineered systems can carry risk of high failure consequences, and as a result, resilience—the ability to avoid or quickly recover from faults—is desirable. Ideally, resilience should be designed-in as early in the design process as possible so that designers can best leverage the ability to explore the design space. Toward this end, previous work has developed functional modeling languages which represent the functions which must be performed by a system and function-based fault modeling frameworks have been developed to predict the resulting fault propagation behavior of a given functional model. However, little has been done to formally optimize or compare designs based on these predictions, partially because the effects of these models have not been quantified into an objective function to optimize. The work described herein closes this gap by introducing the resilience-informed scenario cost sum (RISCS), a scoring function which integrates with a fault scenario-based simulation, to enable the optimization and evaluation of functional model resilience. The scoring function accomplishes this by quantifying the expected cost of a design's fault response using probability information, and combining this cost with design and operational costs such that it may be parameterized in terms of designer-specified resilient features. The usefulness and limitations of using this approach in a general optimization and concept selection framework are discussed in general, and demonstrated on a monopropellant system design problem. Using RISCS as an objective for optimization, the algorithm selects the set of resilient features which provides the optimal trade-off between design cost and risk. For concept selection, RISCS is used to judge whether resilient concept variants justify their design costs and make direct comparisons between different model structures.
Topology Optimization Under Stress Relaxation Effect Using Internal Element Connectivity Parameterization
Authors: Takalloozadeh Meisam , Yoon Gil ho
Published: September 2018

The creep phenomenon has enormous effect on the stress and displacement distribution in the structures. Redistribution of the stress field is one of these effects which is called stress relaxation. The importance of stress relaxation in the design of structures is increasing due to engineering applications especially in high temperature. However, this phenomenon has remained absent from the structural optimization studies. In the present study, the effect of stress relaxation due to high temperature creep is considered in topology optimization (TO). Internal element connectivity parameterization (I-ECP) method is utilized for performing TO. This method is shown to be effective to overcome numerical instabilities in nonlinear problems. Time-dependent adjoint sensitivity formulation is implemented for I-ECP including creep effect. Several benchmark problems are solved, and the optimum layouts obtained by linear and nonlinear methods are compared to show the efficiency of the proposed method and to show the effect of stress relaxation on the optimum layout.
Extension of Maggi and Kane Equations to Holonomic Dynamic Systems
Authors: Haug Edward J.
Published: September 2018

The Maggi and Kane equations of motion are valid for systems with only nonholonomic constraints, but may fail when applied to systems with holonomic constraints. A tangent space ordinary differential equation (ODE) extension of the Maggi and Kane formulations that enforces holonomic constraints is presented and shown to be theoretically sound and computationally effective. Numerical examples are presented that demonstrate the extended formulation leads to solutions that satisfy position, velocity, and acceleration constraints for holonomic systems to near computer precision.
A Performance Study of Controlled Impact Timing on Harmonics Reduction in Operational Modal Testing
Authors: Lim Hong Cheet , Ong Zhi Chao , Ismail Zubaidah , Khoo Shin Yee
Published: September 2018

As an alternative to operational modal analysis and classical experimental modal analysis (EMA), a novel method was introduced previously, namely impact-synchronous modal analysis (ISMA). The effectiveness ISMA on rotor and structural dynamic systems has been proven in previous literature. More recently, an automated impact device (AID) was introduced which utilized tachometer pulse as initiation signal and its effectiveness on ISMA was proven. An attempt to further enhance this device in term of equipment and cost is then proposed by replacing the tachometer with the in-use tri-axial accelerometer through utilizing the filtered response of cyclic load component as an initiation signal to control the impact device, which is also the primary aim for this study. Prior to modal testing, accuracy of this device is illustrated at desired phase angles of 0 deg, 90 deg, 180 deg, and 270 deg. Subsequently, frequency response function (FRF) estimations obtained for ISMA using enhanced AID has demonstrated the suppression capabilities of this device on disturbances, i.e., reduction of 93.58% at 30 Hz and 57.78% at 60 Hz, resulting in a high correlation for signature assurance criterion (SAC) and cross signature assurance criterion (CSAC). Modal parameters extracted from the EMA and ISMA using impact device are presented and compared, for the first three natural modes of the test rig. It is found that natural frequencies are deviating by less than 6%, whereas modal assurance criterion (MAC) values between the mode shapes of the two tests are found to be above 0.9.
DirCol5i: Trajectory Optimization for Problems With High-Order Derivatives
Authors: Kelly Matthew P.
Published: September 2018

In this technical brief, we focus on solving trajectory optimization problems that have nonlinear system dynamics and that include high-order derivatives in the objective function. This type of problem comes up in robotics—for example, when computing minimum-snap reference trajectories for a quadrotor or computing minimum-jerk trajectories for a robot arm. DirCol5i is a transcription method that is specialized for solving this type of problem. It uses the fifth-order splines and analytic differentiation to compute higher-derivatives, rather than using a chain-integrator as would be required by traditional methods. We compare DirCol5i to traditional transcription methods. Although it is slower for some simple optimization problems, when solving problems with high-order derivatives DirCol5i is faster, more numerically robust, and does not require setting up a chain integrator.
Optimized structure of standard sample with programed defects for pattern inspection using electron beams
Authors: Iida Susumu , Uchiyama Takayuki
Published: October 2018

Standard samples with programed defects, designed to evaluate pattern inspection tools that use electron beams, were fabricated on 12-in. Si wafer. By using a structure with a conductive pattern on an insulator layer, scanning electron microscope (SEM) images with various pattern contrasts, depending on the charging effect, were obtained under different observation conditions. The impact of captured-image contrast on defect detection capability was examined using different types of inspection algorithm. It was found that the accuracy of critical dimension measurement, effectiveness of the charge suppression technique, and defect detection capability of the SEM tool, and its robustness could all be evaluated using this standard sample with a particular stacked structure.
Emergence and Within-Host Genetic Evolution of Methicillin-Resistant
Staphylococcus aureus
Resistant to Linezolid in a Cystic Fibrosis Patient
Authors: Rouard Caroline , Garnier Fabien , Leraut Jeremy , Lepainteur Margaux , Rahajamananav Lalaina , Languepin Jeanne , Ploy Marie-Cécile , Bourgeois-Nicolaos Nadège , Doucet-Populaire Florence
Published: October 2018

Methicillin-resistant
Staphylococcus aureus
(MRSA) infection has increased in recent years among cystic fibrosis (CF) patients. Linezolid (LZD) is one of the antistaphylococcal antibiotics widely used in this context.
A Phase 1 Study To Assess the Pharmacokinetics of Intravenous Plazomicin in Adult Subjects with Varying Degrees of Renal Function
Authors: Komirenko Allison S. , Riddle Valerie , Gibbons Jacqueline A. , Van Wart Scott , Seroogy Julie D.
Published: October 2018

Plazomicin is an FDA-approved aminoglycoside for the treatment of complicated urinary tract infections. In this open-label study, 24 adults with normal renal function or mild, moderate, or severe renal impairment (
n
= 6 per group) received a single 7.5-mg/kg of body weight dose of plazomicin as a 30-min intravenous infusion.
Gardener-associated fibroma: an unusual cause of upper airway obstruction
Authors: Pinto Rohan Sebastian , Simons Anthony , Verma Rohit , Bateman Neil
Published: September 2018

We present the first case of upper airway obstruction secondary to a retropharyngeal Gardner-associated fibroma (GAF). A 16-month-old infant presented with a 3-month history of worsening dyspnoea and apnoeic episodes. Examination revealed stridor and left-sided retropharyngeal asymmetry. MRI demonstrated a mass in the retropharynx. Tracheostomy and pharyngeal biopsy under anaesthesia were performed, and histology confirmed a diagnosis of GAF. The mass was excised using a transcervical approach, and postoperative recovery was unremarkable. GAF is associated with Gardner’s syndrome (GS) and familial adenomatous polyposis (FAP), both of which are associated with multiple colonic polyps and increased risk of colorectal malignancy. Subsequent testing for an APC mutation seen in GS and FAP was negative in our patient. The details of this unusual presentation of a rare disease are given in addition to a review of the literature.
A delayed diagnosis: recurrent fever and beta thalassaemia
Authors: Samarkos Michael , Mantzourani Marina , Nika Christina , Kalotychou Vasiliki
Published: October 2018

Familial Mediterranean fever and beta-thalassaemia are two genetic disorders, with a largely common geographical distribution. However, they have not much else in common, as the first is an autoinflammatory disorder, while the other is a haemoglobinopathy. We describe a patient with known beta-thalassaemia intermedia who presented with recurrent fevers and he was diagnosed with familial Mediterranean fever 2 years later. We discuss whether there is an association between the two disorders and the cognitive biases that lead to the delay in the diagnosis of familial Mediterranean fever.
Liver transplantation for inferior vena cava leiomyosarcoma: from a Maslow’s hammer to the Occam’s razor
Authors: Gunasekaran Vasanthakumar , Rammohan Ashwin , Reddy Srinivas Mettu , Rela Mohamed
Published: September 2018

Leiomyosarcoma (LMS) of primary vascular origin is a rare entity with only potentially curative option being complete surgical resection; despite which the prognosis remains dismal. Tumour recurrence is very common, and the benefits of adjuvant therapy are undefined. A 39-year-old woman presented with 6 months’ history of abdominal pain, abdominal distension and pedal oedema. On evaluation, she was diagnosed to have chronic Budd-Chiari syndrome (BCS) secondary to a tumour arising from the inferior vena cava (IVC) on evaluation. Her liver decompensation included jaundice, gastrointestinal bleed and ascites. Following a detailed multidisciplinary team discussion, she underwent complete excision of the tumour along with a segment of the IVC with living donor liver transplantation. She remains disease-free 24 months following surgery. This is the first reported case of liver transplantation for IVC LMS causing chronic BCS.
Modified laparoscopic Janeway gastrostomy: a novel adjunct for the management of choledocholithiasis in Roux-en-Y patients
Authors: Robalino Ryan , Liu Shinban , Ferzli George
Published: October 2018

A 76-year-old woman with surgical history of Roux-en-Y gastric bypass presented with recurrent choledocholithiasis. Double balloon enteroscopy was unsuccessful in cannulating the biliary tree, thus, requiring surgically assisted endoscopic retrograde cholangiopancreaticogram (ERCP) access. Due to her stable clinical status, the non-urgent indication and multiple anticipated ERCPs for definitive biliary clearance, a more durable port of access to the ampulla was desired. A modified laparoscopic Janeway gastrostomy of the gastric remnant was performed and served as access for multiple subsequent endoscopic procedures with successful clearance of the biliary tree.